* [PATCH 00/18] Introduce discontiguous frames management
@ 2025-04-02 17:23 Laurent Vivier
2025-04-02 17:23 ` [PATCH 01/18] arp: Don't mix incoming and outgoing buffers Laurent Vivier
` (17 more replies)
0 siblings, 18 replies; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
This series introduces iov_tail to convey frame information
between functions.
This is only an API change, for the moment the memory pool
is only able to store contiguous buffer, so, except for
vhost-user in a special case, we only play with iovec array
with only one entry.
Laurent Vivier (18):
arp: Don't mix incoming and outgoing buffers
iov: Update IOV_REMOVE_HEADER() and IOV_PEEK_HEADER()
tap: Use iov_tail with tap_add_packet()
packet: Use iov_tail with packet_add()
packet: Add packet_base()
arp: Convert to iov_tail
ndp: Convert to iov_tail
icmp: Convert to iov_tail
udp: Convert to iov_tail
tcp: Convert tcp_tap_handler() to use iov_tail
tcp: Convert tcp_data_from_tap() to use iov_tail
dhcpv6: Convert to iov_tail
dhcpv6: move offset initialization out of dhcpv6_opt()
dhcpv6: Use iov_tail in dhcpv6_opt()
dhcp: Convert to iov_tail
tap: Convert to iov_tail
ip: Use iov_tail in ipv6_l4hdr()
tap: Convert to iov_tail
arp.c | 90 ++++++++++++++++++++++++------------
dhcp.c | 38 ++++++++-------
dhcpv6.c | 70 +++++++++++++++-------------
icmp.c | 38 +++++++++------
iov.c | 130 ++++++++++++++++++++++++++++++++++++++++++++++++----
iov.h | 54 ++++++++++++++++------
ip.c | 27 +++++------
ip.h | 3 +-
ndp.c | 7 ++-
packet.c | 58 ++++++++++-------------
packet.h | 19 ++++----
pcap.c | 1 +
tap.c | 86 ++++++++++++++++++++++------------
tap.h | 2 +-
tcp.c | 41 +++++++++++------
tcp_buf.c | 2 +-
udp.c | 37 ++++++++++-----
vu_common.c | 25 ++--------
18 files changed, 474 insertions(+), 254 deletions(-)
--
2.49.0
^ permalink raw reply [flat|nested] 34+ messages in thread
* [PATCH 01/18] arp: Don't mix incoming and outgoing buffers
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 1:57 ` David Gibson
2025-04-02 17:23 ` [PATCH 02/18] iov: Update IOV_REMOVE_HEADER() and IOV_PEEK_HEADER() Laurent Vivier
` (16 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Don't use the memory of the incoming packet to build the outgoing buffer
as it can be memory of the TX queue in the case of vhost-user.
Moreover with vhost-user, the packet can be splitted accross several
iovec and it's easier to rebuild it in a buffer than updating an
existing iovec array.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
arp.c | 84 ++++++++++++++++++++++++++++++++++++++---------------------
1 file changed, 55 insertions(+), 29 deletions(-)
diff --git a/arp.c b/arp.c
index fc482bbd9938..9d68d7c3b602 100644
--- a/arp.c
+++ b/arp.c
@@ -31,56 +31,82 @@
#include "tap.h"
/**
- * arp() - Check if this is a supported ARP message, reply as needed
+ * ignore_arp() - Check if this is a supported ARP message
* @c: Execution context
- * @p: Packet pool, single packet with Ethernet buffer
+ * @ah: ARP header
+ * @am: ARP message
*
- * Return: 1 if handled, -1 on failure
+ * Return: true if the message is supported, false otherwise.
*/
-int arp(const struct ctx *c, const struct pool *p)
+static bool ignore_arp(const struct ctx *c,
+ const struct arphdr *ah, const struct arpmsg *am)
{
- unsigned char swap[4];
- struct ethhdr *eh;
- struct arphdr *ah;
- struct arpmsg *am;
- size_t l2len;
-
- eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
- ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
- am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
-
- if (!eh || !ah || !am)
- return -1;
-
if (ah->ar_hrd != htons(ARPHRD_ETHER) ||
ah->ar_pro != htons(ETH_P_IP) ||
ah->ar_hln != ETH_ALEN ||
ah->ar_pln != 4 ||
ah->ar_op != htons(ARPOP_REQUEST))
- return 1;
+ return true;
/* Discard announcements, but not 0.0.0.0 "probes" */
if (memcmp(am->sip, &in4addr_any, sizeof(am->sip)) &&
!memcmp(am->sip, am->tip, sizeof(am->sip)))
- return 1;
+ return true;
/* Don't resolve the guest's assigned address, either. */
if (!memcmp(am->tip, &c->ip4.addr, sizeof(am->tip)))
+ return true;
+
+ return false;
+}
+
+/**
+ * arp() - Check if this is a supported ARP message, reply as needed
+ * @c: Execution context
+ * @p: Packet pool, single packet with Ethernet buffer
+ *
+ * Return: 1 if handled, -1 on failure
+ */
+int arp(const struct ctx *c, const struct pool *p)
+{
+ struct {
+ struct ethhdr eh;
+ struct arphdr ah;
+ struct arpmsg am;
+ } __attribute__((__packed__)) resp;
+ const struct ethhdr *eh;
+ const struct arphdr *ah;
+ const struct arpmsg *am;
+
+ eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
+ ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
+ am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
+
+ if (!eh || !ah || !am)
+ return -1;
+
+ if (ignore_arp(c, ah, am))
return 1;
- ah->ar_op = htons(ARPOP_REPLY);
- memcpy(am->tha, am->sha, sizeof(am->tha));
- memcpy(am->sha, c->our_tap_mac, sizeof(am->sha));
+ /* ethernet header */
+ resp.eh.h_proto = htons(ETH_P_ARP);
+ memcpy(resp.eh.h_dest, eh->h_source, sizeof(resp.eh.h_dest));
+ memcpy(resp.eh.h_source, c->our_tap_mac, sizeof(resp.eh.h_source));
- memcpy(swap, am->tip, sizeof(am->tip));
- memcpy(am->tip, am->sip, sizeof(am->tip));
- memcpy(am->sip, swap, sizeof(am->sip));
+ /* ARP header */
+ resp.ah.ar_op = htons(ARPOP_REPLY);
+ resp.ah.ar_hrd = ah->ar_hrd;
+ resp.ah.ar_pro = ah->ar_pro;
+ resp.ah.ar_hln = ah->ar_hln;
+ resp.ah.ar_pln = ah->ar_pln;
- l2len = sizeof(*eh) + sizeof(*ah) + sizeof(*am);
- memcpy(eh->h_dest, eh->h_source, sizeof(eh->h_dest));
- memcpy(eh->h_source, c->our_tap_mac, sizeof(eh->h_source));
+ /* ARP message */
+ memcpy(resp.am.sha, c->our_tap_mac, sizeof(resp.am.sha));
+ memcpy(resp.am.sip, am->tip, sizeof(resp.am.sip));
+ memcpy(resp.am.tha, am->sha, sizeof(resp.am.tha));
+ memcpy(resp.am.tip, am->sip, sizeof(resp.am.tip));
- tap_send_single(c, eh, l2len);
+ tap_send_single(c, &resp, sizeof(resp));
return 1;
}
--
@@ -31,56 +31,82 @@
#include "tap.h"
/**
- * arp() - Check if this is a supported ARP message, reply as needed
+ * ignore_arp() - Check if this is a supported ARP message
* @c: Execution context
- * @p: Packet pool, single packet with Ethernet buffer
+ * @ah: ARP header
+ * @am: ARP message
*
- * Return: 1 if handled, -1 on failure
+ * Return: true if the message is supported, false otherwise.
*/
-int arp(const struct ctx *c, const struct pool *p)
+static bool ignore_arp(const struct ctx *c,
+ const struct arphdr *ah, const struct arpmsg *am)
{
- unsigned char swap[4];
- struct ethhdr *eh;
- struct arphdr *ah;
- struct arpmsg *am;
- size_t l2len;
-
- eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
- ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
- am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
-
- if (!eh || !ah || !am)
- return -1;
-
if (ah->ar_hrd != htons(ARPHRD_ETHER) ||
ah->ar_pro != htons(ETH_P_IP) ||
ah->ar_hln != ETH_ALEN ||
ah->ar_pln != 4 ||
ah->ar_op != htons(ARPOP_REQUEST))
- return 1;
+ return true;
/* Discard announcements, but not 0.0.0.0 "probes" */
if (memcmp(am->sip, &in4addr_any, sizeof(am->sip)) &&
!memcmp(am->sip, am->tip, sizeof(am->sip)))
- return 1;
+ return true;
/* Don't resolve the guest's assigned address, either. */
if (!memcmp(am->tip, &c->ip4.addr, sizeof(am->tip)))
+ return true;
+
+ return false;
+}
+
+/**
+ * arp() - Check if this is a supported ARP message, reply as needed
+ * @c: Execution context
+ * @p: Packet pool, single packet with Ethernet buffer
+ *
+ * Return: 1 if handled, -1 on failure
+ */
+int arp(const struct ctx *c, const struct pool *p)
+{
+ struct {
+ struct ethhdr eh;
+ struct arphdr ah;
+ struct arpmsg am;
+ } __attribute__((__packed__)) resp;
+ const struct ethhdr *eh;
+ const struct arphdr *ah;
+ const struct arpmsg *am;
+
+ eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
+ ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
+ am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
+
+ if (!eh || !ah || !am)
+ return -1;
+
+ if (ignore_arp(c, ah, am))
return 1;
- ah->ar_op = htons(ARPOP_REPLY);
- memcpy(am->tha, am->sha, sizeof(am->tha));
- memcpy(am->sha, c->our_tap_mac, sizeof(am->sha));
+ /* ethernet header */
+ resp.eh.h_proto = htons(ETH_P_ARP);
+ memcpy(resp.eh.h_dest, eh->h_source, sizeof(resp.eh.h_dest));
+ memcpy(resp.eh.h_source, c->our_tap_mac, sizeof(resp.eh.h_source));
- memcpy(swap, am->tip, sizeof(am->tip));
- memcpy(am->tip, am->sip, sizeof(am->tip));
- memcpy(am->sip, swap, sizeof(am->sip));
+ /* ARP header */
+ resp.ah.ar_op = htons(ARPOP_REPLY);
+ resp.ah.ar_hrd = ah->ar_hrd;
+ resp.ah.ar_pro = ah->ar_pro;
+ resp.ah.ar_hln = ah->ar_hln;
+ resp.ah.ar_pln = ah->ar_pln;
- l2len = sizeof(*eh) + sizeof(*ah) + sizeof(*am);
- memcpy(eh->h_dest, eh->h_source, sizeof(eh->h_dest));
- memcpy(eh->h_source, c->our_tap_mac, sizeof(eh->h_source));
+ /* ARP message */
+ memcpy(resp.am.sha, c->our_tap_mac, sizeof(resp.am.sha));
+ memcpy(resp.am.sip, am->tip, sizeof(resp.am.sip));
+ memcpy(resp.am.tha, am->sha, sizeof(resp.am.tha));
+ memcpy(resp.am.tip, am->sip, sizeof(resp.am.tip));
- tap_send_single(c, eh, l2len);
+ tap_send_single(c, &resp, sizeof(resp));
return 1;
}
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 02/18] iov: Update IOV_REMOVE_HEADER() and IOV_PEEK_HEADER()
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
2025-04-02 17:23 ` [PATCH 01/18] arp: Don't mix incoming and outgoing buffers Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 2:36 ` David Gibson
2025-04-02 17:23 ` [PATCH 03/18] tap: Use iov_tail with tap_add_packet() Laurent Vivier
` (15 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Provide a temporary variable of the wanted type to store
the header if the memory in the iovec array is not contiguous.
Also introduce iov_tail_ptr(), iov_drop() and iov_copy()
for later use.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
iov.c | 133 ++++++++++++++++++++++++++++++++++++++++++++++++++----
iov.h | 53 ++++++++++++++++------
tcp_buf.c | 2 +-
3 files changed, 163 insertions(+), 25 deletions(-)
diff --git a/iov.c b/iov.c
index 8c63b7ea6e31..d96fc2ab594b 100644
--- a/iov.c
+++ b/iov.c
@@ -108,7 +108,7 @@ size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt,
*
* Returns: The number of bytes successfully copied.
*/
-/* cppcheck-suppress unusedFunction */
+/* cppcheck-suppress [staticFunction,unmatchedSuppression] */
size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
size_t offset, void *buf, size_t bytes)
{
@@ -126,6 +126,7 @@ size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
/* copying data */
for (copied = 0; copied < bytes && i < iov_cnt; i++) {
size_t len = MIN(iov[i].iov_len - offset, bytes - copied);
+ /* NOLINTNEXTLINE(clang-analyzer-core.NonNullParamChecker) */
memcpy((char *)buf + copied, (char *)iov[i].iov_base + offset,
len);
copied += len;
@@ -156,6 +157,45 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt)
return len;
}
+/**
+ * iov_copy - Copy data from one scatter/gather I/O vector (struct iovec) to
+ * another.
+ *
+ * @dst_iov: Pointer to the destination array of struct iovec describing
+ * the scatter/gather I/O vector to copy to.
+ * @dst_iov_cnt: Number of elements in the destination iov array.
+ * @iov: Pointer to the source array of struct iovec describing
+ * the scatter/gather I/O vector to copy from.
+ * @iov_cnt: Number of elements in the source iov array.
+ * @offset: Offset within the source iov from where copying should start.
+ * @bytes: Total number of bytes to copy from iov to dst_iov.
+ *
+ * Returns: The number of elements successfully copied to the destination
+ * iov array.
+ */
+/* cppcheck-suppress unusedFunction */
+unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
+ const struct iovec *iov, size_t iov_cnt,
+ size_t offset, size_t bytes)
+{
+ unsigned int i, j;
+
+ i = iov_skip_bytes(iov, iov_cnt, offset, &offset);
+
+ /* copying data */
+ for (j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) {
+ size_t len = MIN(bytes, iov[i].iov_len - offset);
+
+ dst_iov[j].iov_base = (char *)iov[i].iov_base + offset;
+ dst_iov[j].iov_len = len;
+ j++;
+ bytes -= len;
+ offset = 0;
+ }
+
+ return j;
+}
+
/**
* iov_tail_prune() - Remove any unneeded buffers from an IOV tail
* @tail: IO vector tail (modified)
@@ -192,7 +232,50 @@ size_t iov_tail_size(struct iov_tail *tail)
}
/**
- * iov_peek_header_() - Get pointer to a header from an IOV tail
+ * iov_drop() - update head of the tail
+ * @tail: IO vector tail
+ * @len: length to move the head of the tail
+ *
+ * Returns: true if the tail still contains any bytes, otherwise false
+ */
+/* cppcheck-suppress unusedFunction */
+bool iov_drop(struct iov_tail *tail, size_t len)
+{
+ tail->off = tail->off + len;
+
+ return iov_tail_prune(tail);
+}
+
+/**
+ * iov_tail_ptr() - get a pointer to the head of the tail
+ * @tail: IO vector tail
+ * @off: Byte offset in the tail to skip
+ * @len: Length of the data to get, in bytes
+ *
+ * Returns: pointer to the data in the tail, NULL if the
+ * tail doesn't contains @len bytes.
+ */
+/* cppcheck-suppress unusedFunction */
+void *iov_tail_ptr(struct iov_tail *tail, size_t off, size_t len)
+{
+ const struct iovec *iov;
+ size_t cnt, i;
+
+ i = iov_skip_bytes(tail->iov, tail->cnt, tail->off + off, &off);
+ if (i == tail->cnt)
+ return NULL;
+
+ iov = &tail->iov[i];
+ cnt = tail->cnt - i;
+
+ if (iov_size(iov, cnt) < off + len)
+ return NULL;
+
+ return (char *)iov[0].iov_base + off;
+}
+
+/**
+ * iov_check_header - Check if a header can be accessed
* @tail: IOV tail to get header from
* @len: Length of header to get, in bytes
* @align: Required alignment of header, in bytes
@@ -203,8 +286,7 @@ size_t iov_tail_size(struct iov_tail *tail)
* overruns the IO vector, is not contiguous or doesn't have the
* requested alignment.
*/
-/* cppcheck-suppress [staticFunction,unmatchedSuppression] */
-void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align)
+static void *iov_check_header(struct iov_tail *tail, size_t len, size_t align)
{
char *p;
@@ -225,7 +307,36 @@ void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align)
}
/**
- * iov_remove_header_() - Remove a header from an IOV tail
+ * iov_peek_header_ - Get pointer to a header from an IOV tail
+ * @tail: IOV tail to get header from
+ * @len: Length of header to get, in bytes
+ * @align: Required alignment of header, in bytes
+ *
+ * @tail may be pruned, but will represent the same bytes as before.
+ *
+ * Returns: Pointer to the first @len logical bytes of the tail, or to
+ * a copy if that overruns the IO vector, is not contiguous or
+ * doesn't have the requested alignment. NULL if that overruns the
+ * IO vector.
+ */
+/* cppcheck-suppress [staticFunction,unmatchedSuppression] */
+void *iov_peek_header_(struct iov_tail *tail, void *v, size_t len, size_t align)
+{
+ char *p = iov_check_header(tail, len, align);
+ size_t l;
+
+ if (p)
+ return p;
+
+ l = iov_to_buf(tail->iov, tail->cnt, tail->off, v, len);
+ if (l != len)
+ return NULL;
+
+ return v;
+}
+
+/**
+ * iov_remove_header_ - Remove a header from an IOV tail
* @tail: IOV tail to remove header from (modified)
* @len: Length of header to remove, in bytes
* @align: Required alignment of header, in bytes
@@ -233,17 +344,19 @@ void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align)
* On success, @tail is updated so that it longer includes the bytes of the
* returned header.
*
- * Returns: Pointer to the first @len logical bytes of the tail, NULL if that
- * overruns the IO vector, is not contiguous or doesn't have the
- * requested alignment.
+ * Returns: Pointer to the first @len logical bytes of the tail, or to
+ * a copy if that overruns the IO vector, is not contiguous or
+ * doesn't have the requested alignment. NULL if that overruns the
+ * IO vector.
*/
-void *iov_remove_header_(struct iov_tail *tail, size_t len, size_t align)
+void *iov_remove_header_(struct iov_tail *tail, void *v, size_t len, size_t align)
{
- char *p = iov_peek_header_(tail, len, align);
+ char *p = iov_peek_header_(tail, v, len, align);
if (!p)
return NULL;
tail->off = tail->off + len;
+
return p;
}
diff --git a/iov.h b/iov.h
index 9855bf0c0c32..f9b5fdf0803e 100644
--- a/iov.h
+++ b/iov.h
@@ -28,6 +28,9 @@ size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt,
size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
size_t offset, void *buf, size_t bytes);
size_t iov_size(const struct iovec *iov, size_t iov_cnt);
+unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
+ const struct iovec *iov, size_t iov_cnt,
+ size_t offset, size_t bytes);
/*
* DOC: Theory of Operation, struct iov_tail
@@ -70,38 +73,60 @@ struct iov_tail {
#define IOV_TAIL(iov_, cnt_, off_) \
(struct iov_tail){ .iov = (iov_), .cnt = (cnt_), .off = (off_) }
+/**
+ * IOV_TAIL_FROM_BUF() - Create a new IOV tail from a buffer
+ * @buf_: Buffer address to use in the iovec
+ * @len_: Buffer size
+ * @off_: Byte offset in the buffer where the tail begins
+ */
+#define IOV_TAIL_FROM_BUF(buf_, len_, off_) \
+ IOV_TAIL((&(const struct iovec){ .iov_base = (buf_), .iov_len = (len_) }), 1, (off_))
+
bool iov_tail_prune(struct iov_tail *tail);
size_t iov_tail_size(struct iov_tail *tail);
-void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align);
-void *iov_remove_header_(struct iov_tail *tail, size_t len, size_t align);
+bool iov_drop(struct iov_tail *tail, size_t len);
+void *iov_peek_header_(struct iov_tail *tail, void *v, size_t len, size_t align);
+void *iov_remove_header_(struct iov_tail *tail, void *v, size_t len, size_t align);
+void *iov_tail_ptr(struct iov_tail *tail, size_t off, size_t len);
/**
* IOV_PEEK_HEADER() - Get typed pointer to a header from an IOV tail
* @tail_: IOV tail to get header from
- * @type_: Data type of the header
+ * @var_: Temporary buffer of the type of the header to use if
+ * the memory in the iovec array is not contiguous.
*
* @tail_ may be pruned, but will represent the same bytes as before.
*
- * Returns: Pointer of type (@type_ *) located at the start of @tail_, NULL if
- * we can't get a contiguous and aligned pointer.
+ * Returns: Pointer of type (@type_ *) located at the start of @tail_
*/
-#define IOV_PEEK_HEADER(tail_, type_) \
- ((type_ *)(iov_peek_header_((tail_), \
- sizeof(type_), __alignof__(type_))))
+
+#define IOV_PEEK_HEADER(tail_, var_) \
+ ((__typeof__(var_) *)(iov_peek_header_((tail_), &(var_), \
+ sizeof(var_), __alignof__(var_))))
/**
* IOV_REMOVE_HEADER() - Remove and return typed header from an IOV tail
* @tail_: IOV tail to remove header from (modified)
- * @type_: Data type of the header to remove
+ * @var_: Temporary buffer of the type of the header to use if
+ * the memory in the iovec array is not contiguous.
*
* On success, @tail_ is updated so that it longer includes the bytes of the
* returned header.
*
- * Returns: Pointer of type (@type_ *) located at the old start of @tail_, NULL
- * if we can't get a contiguous and aligned pointer.
+ * Returns: Pointer of type (@type_ *) located at the old start of @tail_
+ */
+
+#define IOV_REMOVE_HEADER(tail_, var_) \
+ ((__typeof__(var_) *)(iov_remove_header_((tail_), &(var_), \
+ sizeof(var_), __alignof__(var_))))
+
+/** IOV_DROP_HEADER() -- Remove a typed header from an IOV tail
+ * @tail_: IOV tail to remove header from (modified)
+ * @type_: Data type of the header to remove
+ *
+ * Returns: true if the tail still contains any bytes, otherwise false
*/
-#define IOV_REMOVE_HEADER(tail_, type_) \
- ((type_ *)(iov_remove_header_((tail_), \
- sizeof(type_), __alignof__(type_))))
+#define IOV_DROP_HEADER(tail_, type_) \
+ iov_drop((tail_), sizeof(type_))
#endif /* IOVEC_H */
diff --git a/tcp_buf.c b/tcp_buf.c
index 05305636b503..4bcc1acb245a 100644
--- a/tcp_buf.c
+++ b/tcp_buf.c
@@ -160,7 +160,7 @@ static void tcp_l2_buf_fill_headers(const struct tcp_tap_conn *conn,
uint32_t seq, bool no_tcp_csum)
{
struct iov_tail tail = IOV_TAIL(&iov[TCP_IOV_PAYLOAD], 1, 0);
- struct tcphdr *th = IOV_REMOVE_HEADER(&tail, struct tcphdr);
+ struct tcphdr thc, *th = IOV_REMOVE_HEADER(&tail, thc);
struct tap_hdr *taph = iov[TCP_IOV_TAP].iov_base;
const struct flowside *tapside = TAPFLOW(conn);
const struct in_addr *a4 = inany_v4(&tapside->oaddr);
--
@@ -160,7 +160,7 @@ static void tcp_l2_buf_fill_headers(const struct tcp_tap_conn *conn,
uint32_t seq, bool no_tcp_csum)
{
struct iov_tail tail = IOV_TAIL(&iov[TCP_IOV_PAYLOAD], 1, 0);
- struct tcphdr *th = IOV_REMOVE_HEADER(&tail, struct tcphdr);
+ struct tcphdr thc, *th = IOV_REMOVE_HEADER(&tail, thc);
struct tap_hdr *taph = iov[TCP_IOV_TAP].iov_base;
const struct flowside *tapside = TAPFLOW(conn);
const struct in_addr *a4 = inany_v4(&tapside->oaddr);
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 03/18] tap: Use iov_tail with tap_add_packet()
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
2025-04-02 17:23 ` [PATCH 01/18] arp: Don't mix incoming and outgoing buffers Laurent Vivier
2025-04-02 17:23 ` [PATCH 02/18] iov: Update IOV_REMOVE_HEADER() and IOV_PEEK_HEADER() Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 4:50 ` David Gibson
2025-04-02 17:23 ` [PATCH 04/18] packet: Use iov_tail with packet_add() Laurent Vivier
` (14 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use IOV_PEEK_HEADER() to get the ethernet header from the iovec.
Move the workaround about multiple iovec array from vu_handle_tx() to
tap_add_packet(). Removing the offset out of the iovec array should
reduce the iovec count to 1.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
iov.c | 1 -
pcap.c | 1 +
tap.c | 30 +++++++++++++++++++++---------
tap.h | 2 +-
vu_common.c | 25 +++++--------------------
5 files changed, 28 insertions(+), 31 deletions(-)
diff --git a/iov.c b/iov.c
index d96fc2ab594b..508fb6da91fb 100644
--- a/iov.c
+++ b/iov.c
@@ -238,7 +238,6 @@ size_t iov_tail_size(struct iov_tail *tail)
*
* Returns: true if the tail still contains any bytes, otherwise false
*/
-/* cppcheck-suppress unusedFunction */
bool iov_drop(struct iov_tail *tail, size_t len)
{
tail->off = tail->off + len;
diff --git a/pcap.c b/pcap.c
index e95aa6fe29a6..404043a27e22 100644
--- a/pcap.c
+++ b/pcap.c
@@ -76,6 +76,7 @@ static void pcap_frame(const struct iovec *iov, size_t iovcnt,
* @pkt: Pointer to data buffer, including L2 headers
* @l2len: L2 frame length
*/
+/* cppcheck-suppress unusedFunction */
void pcap(const char *pkt, size_t l2len)
{
struct iovec iov = { (char *)pkt, l2len };
diff --git a/tap.c b/tap.c
index 182a1151f139..ab3effe80f89 100644
--- a/tap.c
+++ b/tap.c
@@ -1040,29 +1040,36 @@ void tap_handler(struct ctx *c, const struct timespec *now)
/**
* tap_add_packet() - Queue/capture packet, update notion of guest MAC address
* @c: Execution context
- * @l2len: Total L2 packet length
- * @p: Packet buffer
+ * @data: Packet to add to the pool
*/
-void tap_add_packet(struct ctx *c, ssize_t l2len, char *p)
+void tap_add_packet(struct ctx *c, struct iov_tail *data)
{
const struct ethhdr *eh;
+ struct ethhdr ehc;
- pcap(p, l2len);
+ pcap_iov(data->iov, data->cnt, data->off);
- eh = (struct ethhdr *)p;
+ eh = IOV_PEEK_HEADER(data, ehc);
+ if (!eh)
+ return;
if (memcmp(c->guest_mac, eh->h_source, ETH_ALEN)) {
memcpy(c->guest_mac, eh->h_source, ETH_ALEN);
proto_update_l2_buf(c->guest_mac, NULL);
}
+ iov_tail_prune(data);
+ ASSERT(data->cnt == 1); /* packet_add() doesn't support iovec */
+
switch (ntohs(eh->h_proto)) {
case ETH_P_ARP:
case ETH_P_IP:
- packet_add(pool_tap4, l2len, p);
+ packet_add(pool_tap4, data->iov[0].iov_len - data->off,
+ (char *)data->iov[0].iov_base + data->off);
break;
case ETH_P_IPV6:
- packet_add(pool_tap6, l2len, p);
+ packet_add(pool_tap6, data->iov[0].iov_len - data->off,
+ (char *)data->iov[0].iov_base + data->off);
break;
default:
break;
@@ -1128,6 +1135,7 @@ static void tap_passt_input(struct ctx *c, const struct timespec *now)
while (n >= (ssize_t)sizeof(uint32_t)) {
uint32_t l2len = ntohl_unaligned(p);
+ struct iov_tail data;
if (l2len < sizeof(struct ethhdr) || l2len > L2_MAX_LEN_PASST) {
err("Bad frame size from guest, resetting connection");
@@ -1142,7 +1150,8 @@ static void tap_passt_input(struct ctx *c, const struct timespec *now)
p += sizeof(uint32_t);
n -= sizeof(uint32_t);
- tap_add_packet(c, l2len, p);
+ data = IOV_TAIL_FROM_BUF(p, l2len, 0);
+ tap_add_packet(c, &data);
p += l2len;
n -= l2len;
@@ -1186,6 +1195,8 @@ static void tap_pasta_input(struct ctx *c, const struct timespec *now)
for (n = 0;
n <= (ssize_t)(sizeof(pkt_buf) - L2_MAX_LEN_PASTA);
n += len) {
+ struct iov_tail data;
+
len = read(c->fd_tap, pkt_buf + n, L2_MAX_LEN_PASTA);
if (len == 0) {
@@ -1207,7 +1218,8 @@ static void tap_pasta_input(struct ctx *c, const struct timespec *now)
len > (ssize_t)L2_MAX_LEN_PASTA)
continue;
- tap_add_packet(c, len, pkt_buf + n);
+ data = IOV_TAIL_FROM_BUF(pkt_buf + n, len, 0);
+ tap_add_packet(c, &data);
}
tap_handler(c, now);
diff --git a/tap.h b/tap.h
index dd39fd896f4a..5034acd8ac46 100644
--- a/tap.h
+++ b/tap.h
@@ -119,6 +119,6 @@ void tap_sock_update_pool(void *base, size_t size);
void tap_backend_init(struct ctx *c);
void tap_flush_pools(void);
void tap_handler(struct ctx *c, const struct timespec *now);
-void tap_add_packet(struct ctx *c, ssize_t l2len, char *p);
+void tap_add_packet(struct ctx *c, struct iov_tail *data);
#endif /* TAP_H */
diff --git a/vu_common.c b/vu_common.c
index 686a09b28c8e..e446fc4f2054 100644
--- a/vu_common.c
+++ b/vu_common.c
@@ -159,7 +159,6 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
struct vu_virtq_element elem[VIRTQUEUE_MAX_SIZE];
struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
struct vu_virtq *vq = &vdev->vq[index];
- int hdrlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
int out_sg_count;
int count;
@@ -172,6 +171,7 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
while (count < VIRTQUEUE_MAX_SIZE &&
out_sg_count + VU_MAX_TX_BUFFER_NB <= VIRTQUEUE_MAX_SIZE) {
int ret;
+ struct iov_tail data;
elem[count].out_num = VU_MAX_TX_BUFFER_NB;
elem[count].out_sg = &out_sg[out_sg_count];
@@ -187,25 +187,10 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
warn("virtio-net transmit queue contains no out buffers");
break;
}
- if (elem[count].out_num == 1) {
- tap_add_packet(vdev->context,
- elem[count].out_sg[0].iov_len - hdrlen,
- (char *)elem[count].out_sg[0].iov_base +
- hdrlen);
- } else {
- /* vnet header can be in a separate iovec */
- if (elem[count].out_num != 2) {
- debug("virtio-net transmit queue contains more than one buffer ([%d]: %u)",
- count, elem[count].out_num);
- } else if (elem[count].out_sg[0].iov_len != (size_t)hdrlen) {
- debug("virtio-net transmit queue entry not aligned on hdrlen ([%d]: %d != %zu)",
- count, hdrlen, elem[count].out_sg[0].iov_len);
- } else {
- tap_add_packet(vdev->context,
- elem[count].out_sg[1].iov_len,
- (char *)elem[count].out_sg[1].iov_base);
- }
- }
+
+ data = IOV_TAIL(elem[count].out_sg, elem[count].out_num, 0);
+ if (IOV_DROP_HEADER(&data, struct virtio_net_hdr_mrg_rxbuf))
+ tap_add_packet(vdev->context, &data);
count++;
}
--
@@ -159,7 +159,6 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
struct vu_virtq_element elem[VIRTQUEUE_MAX_SIZE];
struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
struct vu_virtq *vq = &vdev->vq[index];
- int hdrlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
int out_sg_count;
int count;
@@ -172,6 +171,7 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
while (count < VIRTQUEUE_MAX_SIZE &&
out_sg_count + VU_MAX_TX_BUFFER_NB <= VIRTQUEUE_MAX_SIZE) {
int ret;
+ struct iov_tail data;
elem[count].out_num = VU_MAX_TX_BUFFER_NB;
elem[count].out_sg = &out_sg[out_sg_count];
@@ -187,25 +187,10 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
warn("virtio-net transmit queue contains no out buffers");
break;
}
- if (elem[count].out_num == 1) {
- tap_add_packet(vdev->context,
- elem[count].out_sg[0].iov_len - hdrlen,
- (char *)elem[count].out_sg[0].iov_base +
- hdrlen);
- } else {
- /* vnet header can be in a separate iovec */
- if (elem[count].out_num != 2) {
- debug("virtio-net transmit queue contains more than one buffer ([%d]: %u)",
- count, elem[count].out_num);
- } else if (elem[count].out_sg[0].iov_len != (size_t)hdrlen) {
- debug("virtio-net transmit queue entry not aligned on hdrlen ([%d]: %d != %zu)",
- count, hdrlen, elem[count].out_sg[0].iov_len);
- } else {
- tap_add_packet(vdev->context,
- elem[count].out_sg[1].iov_len,
- (char *)elem[count].out_sg[1].iov_base);
- }
- }
+
+ data = IOV_TAIL(elem[count].out_sg, elem[count].out_num, 0);
+ if (IOV_DROP_HEADER(&data, struct virtio_net_hdr_mrg_rxbuf))
+ tap_add_packet(vdev->context, &data);
count++;
}
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 04/18] packet: Use iov_tail with packet_add()
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (2 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 03/18] tap: Use iov_tail with tap_add_packet() Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 4:54 ` David Gibson
2025-04-02 17:23 ` [PATCH 05/18] packet: Add packet_base() Laurent Vivier
` (13 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
iov.h | 1 +
packet.c | 15 ++++++++++++---
packet.h | 8 +++++---
tap.c | 32 ++++++++++++++++++--------------
4 files changed, 36 insertions(+), 20 deletions(-)
diff --git a/iov.h b/iov.h
index f9b5fdf0803e..99442d031549 100644
--- a/iov.h
+++ b/iov.h
@@ -17,6 +17,7 @@
#include <unistd.h>
#include <string.h>
+#include <stdbool.h>
#define IOV_OF_LVALUE(lval) \
(struct iovec){ .iov_base = &(lval), .iov_len = sizeof(lval) }
diff --git a/packet.c b/packet.c
index bcac03750dc0..8b11e0850ff6 100644
--- a/packet.c
+++ b/packet.c
@@ -64,15 +64,16 @@ static int packet_check_range(const struct pool *p, const char *ptr, size_t len,
/**
* packet_add_do() - Add data as packet descriptor to given pool
* @p: Existing pool
- * @len: Length of new descriptor
- * @start: Start of data
+ * @data: Data to add
* @func: For tracing: name of calling function, NULL means no trace()
* @line: For tracing: caller line of function call
*/
-void packet_add_do(struct pool *p, size_t len, const char *start,
+void packet_add_do(struct pool *p, struct iov_tail *data,
const char *func, int line)
{
size_t idx = p->count;
+ const char *start;
+ size_t len;
if (idx >= p->size) {
trace("add packet index %zu to pool with size %zu, %s:%i",
@@ -80,6 +81,14 @@ void packet_add_do(struct pool *p, size_t len, const char *start,
return;
}
+ if (!iov_tail_prune(data))
+ return;
+
+ ASSERT(data->cnt == 1); /* we don't support iovec */
+
+ len = data->iov[0].iov_len - data->off;
+ start = (char *)data->iov[0].iov_base + data->off;
+
if (packet_check_range(p, start, len, func, line))
return;
diff --git a/packet.h b/packet.h
index d099f026631b..f386295da203 100644
--- a/packet.h
+++ b/packet.h
@@ -6,6 +6,8 @@
#ifndef PACKET_H
#define PACKET_H
+#include "iov.h"
+
/* Maximum size of a single packet stored in pool, including headers */
#define PACKET_MAX_LEN UINT16_MAX
@@ -28,15 +30,15 @@ struct pool {
};
int vu_packet_check_range(void *buf, const char *ptr, size_t len);
-void packet_add_do(struct pool *p, size_t len, const char *start,
+void packet_add_do(struct pool *p, struct iov_tail *data,
const char *func, int line);
void *packet_get_do(const struct pool *p, const size_t idx,
size_t offset, size_t len, size_t *left,
const char *func, int line);
void pool_flush(struct pool *p);
-#define packet_add(p, len, start) \
- packet_add_do(p, len, start, __func__, __LINE__)
+#define packet_add(p, data) \
+ packet_add_do(p, data, __func__, __LINE__)
#define packet_get(p, idx, offset, len, left) \
packet_get_do(p, idx, offset, len, left, __func__, __LINE__)
diff --git a/tap.c b/tap.c
index ab3effe80f89..4b54807c4101 100644
--- a/tap.c
+++ b/tap.c
@@ -683,6 +683,7 @@ resume:
size_t l2len, l3len, hlen, l4len;
const struct ethhdr *eh;
const struct udphdr *uh;
+ struct iov_tail data;
struct iphdr *iph;
const char *l4h;
@@ -694,7 +695,8 @@ resume:
if (ntohs(eh->h_proto) == ETH_P_ARP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- packet_add(pkt, l2len, (char *)eh);
+ data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
+ packet_add(pkt, &data);
arp(c, pkt);
continue;
}
@@ -739,7 +741,8 @@ resume:
tap_packet_debug(iph, NULL, NULL, 0, NULL, 1);
- packet_add(pkt, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
+ packet_add(pkt, &data);
icmp_tap_handler(c, PIF_TAP, AF_INET,
&iph->saddr, &iph->daddr,
pkt, now);
@@ -753,7 +756,8 @@ resume:
if (iph->protocol == IPPROTO_UDP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- packet_add(pkt, l2len, (char *)eh);
+ data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
+ packet_add(pkt, &data);
if (dhcp(c, pkt))
continue;
}
@@ -802,7 +806,8 @@ resume:
#undef L4_SET
append:
- packet_add((struct pool *)&seq->p, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
+ packet_add((struct pool *)&seq->p, &data);
}
for (j = 0, seq = tap4_l4; j < seq_count; j++, seq++) {
@@ -858,6 +863,7 @@ resume:
struct in6_addr *saddr, *daddr;
const struct ethhdr *eh;
const struct udphdr *uh;
+ struct iov_tail data;
struct ipv6hdr *ip6h;
uint8_t proto;
char *l4h;
@@ -911,7 +917,8 @@ resume:
if (l4len < sizeof(struct icmp6hdr))
continue;
- packet_add(pkt, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
+ packet_add(pkt, &data);
if (ndp(c, (struct icmp6hdr *)l4h, saddr, pkt))
continue;
@@ -930,7 +937,8 @@ resume:
if (proto == IPPROTO_UDP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- packet_add(pkt, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
+ packet_add(pkt, &data);
if (dhcpv6(c, pkt, saddr, daddr))
continue;
@@ -984,7 +992,8 @@ resume:
#undef L4_SET
append:
- packet_add((struct pool *)&seq->p, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
+ packet_add((struct pool *)&seq->p, &data);
}
for (j = 0, seq = tap6_l4; j < seq_count; j++, seq++) {
@@ -1058,18 +1067,13 @@ void tap_add_packet(struct ctx *c, struct iov_tail *data)
proto_update_l2_buf(c->guest_mac, NULL);
}
- iov_tail_prune(data);
- ASSERT(data->cnt == 1); /* packet_add() doesn't support iovec */
-
switch (ntohs(eh->h_proto)) {
case ETH_P_ARP:
case ETH_P_IP:
- packet_add(pool_tap4, data->iov[0].iov_len - data->off,
- (char *)data->iov[0].iov_base + data->off);
+ packet_add(pool_tap4, data);
break;
case ETH_P_IPV6:
- packet_add(pool_tap6, data->iov[0].iov_len - data->off,
- (char *)data->iov[0].iov_base + data->off);
+ packet_add(pool_tap6, data);
break;
default:
break;
--
@@ -683,6 +683,7 @@ resume:
size_t l2len, l3len, hlen, l4len;
const struct ethhdr *eh;
const struct udphdr *uh;
+ struct iov_tail data;
struct iphdr *iph;
const char *l4h;
@@ -694,7 +695,8 @@ resume:
if (ntohs(eh->h_proto) == ETH_P_ARP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- packet_add(pkt, l2len, (char *)eh);
+ data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
+ packet_add(pkt, &data);
arp(c, pkt);
continue;
}
@@ -739,7 +741,8 @@ resume:
tap_packet_debug(iph, NULL, NULL, 0, NULL, 1);
- packet_add(pkt, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
+ packet_add(pkt, &data);
icmp_tap_handler(c, PIF_TAP, AF_INET,
&iph->saddr, &iph->daddr,
pkt, now);
@@ -753,7 +756,8 @@ resume:
if (iph->protocol == IPPROTO_UDP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- packet_add(pkt, l2len, (char *)eh);
+ data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
+ packet_add(pkt, &data);
if (dhcp(c, pkt))
continue;
}
@@ -802,7 +806,8 @@ resume:
#undef L4_SET
append:
- packet_add((struct pool *)&seq->p, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
+ packet_add((struct pool *)&seq->p, &data);
}
for (j = 0, seq = tap4_l4; j < seq_count; j++, seq++) {
@@ -858,6 +863,7 @@ resume:
struct in6_addr *saddr, *daddr;
const struct ethhdr *eh;
const struct udphdr *uh;
+ struct iov_tail data;
struct ipv6hdr *ip6h;
uint8_t proto;
char *l4h;
@@ -911,7 +917,8 @@ resume:
if (l4len < sizeof(struct icmp6hdr))
continue;
- packet_add(pkt, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
+ packet_add(pkt, &data);
if (ndp(c, (struct icmp6hdr *)l4h, saddr, pkt))
continue;
@@ -930,7 +937,8 @@ resume:
if (proto == IPPROTO_UDP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- packet_add(pkt, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
+ packet_add(pkt, &data);
if (dhcpv6(c, pkt, saddr, daddr))
continue;
@@ -984,7 +992,8 @@ resume:
#undef L4_SET
append:
- packet_add((struct pool *)&seq->p, l4len, l4h);
+ data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
+ packet_add((struct pool *)&seq->p, &data);
}
for (j = 0, seq = tap6_l4; j < seq_count; j++, seq++) {
@@ -1058,18 +1067,13 @@ void tap_add_packet(struct ctx *c, struct iov_tail *data)
proto_update_l2_buf(c->guest_mac, NULL);
}
- iov_tail_prune(data);
- ASSERT(data->cnt == 1); /* packet_add() doesn't support iovec */
-
switch (ntohs(eh->h_proto)) {
case ETH_P_ARP:
case ETH_P_IP:
- packet_add(pool_tap4, data->iov[0].iov_len - data->off,
- (char *)data->iov[0].iov_base + data->off);
+ packet_add(pool_tap4, data);
break;
case ETH_P_IPV6:
- packet_add(pool_tap6, data->iov[0].iov_len - data->off,
- (char *)data->iov[0].iov_base + data->off);
+ packet_add(pool_tap6, data);
break;
default:
break;
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 05/18] packet: Add packet_base()
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (3 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 04/18] packet: Use iov_tail with packet_add() Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 4:59 ` David Gibson
2025-04-02 17:23 ` [PATCH 06/18] arp: Convert to iov_tail Laurent Vivier
` (12 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
packet.c | 37 +++++++++++++++++++++++++++++++++++++
packet.h | 7 +++++++
2 files changed, 44 insertions(+)
diff --git a/packet.c b/packet.c
index 8b11e0850ff6..25ede38b94cb 100644
--- a/packet.c
+++ b/packet.c
@@ -156,6 +156,43 @@ void *packet_get_do(const struct pool *p, size_t idx, size_t offset,
return ptr;
}
+/**
+ * packet_base_do() - Get data range from packet descriptor from given pool
+ * @p: Packet pool
+ * @idx: Index of packet descriptor in pool
+ * @func: For tracing: name of calling function, NULL means no trace()
+ * @line: For tracing: caller line of function call
+ *
+ * Return: pointer to start of data range, NULL on invalid range or descriptor
+ */
+/* cppcheck-suppress unusedFunction */
+bool packet_base_do(const struct pool *p, size_t idx,
+ struct iov_tail *data,
+ const char *func, int line)
+{
+ size_t i;
+
+ if (idx >= p->size || idx >= p->count) {
+ if (func) {
+ trace("packet %zu from pool size: %zu, count: %zu, "
+ "%s:%i", idx, p->size, p->count, func, line);
+ }
+ return NULL;
+ }
+
+ data->cnt = 1;
+ data->off = 0;
+ data->iov = &p->pkt[idx];
+
+ for (i = 0; i < data->cnt; i++) {
+ if (packet_check_range(p, data->iov[i].iov_base,
+ data->iov[i].iov_len, func, line))
+ return false;
+ }
+
+ return true;
+}
+
/**
* pool_flush() - Flush a packet pool
* @p: Pointer to packet pool
diff --git a/packet.h b/packet.h
index f386295da203..35058e747a43 100644
--- a/packet.h
+++ b/packet.h
@@ -35,6 +35,9 @@ void packet_add_do(struct pool *p, struct iov_tail *data,
void *packet_get_do(const struct pool *p, const size_t idx,
size_t offset, size_t len, size_t *left,
const char *func, int line);
+bool packet_base_do(const struct pool *p, const size_t idx,
+ struct iov_tail *data,
+ const char *func, int line);
void pool_flush(struct pool *p);
#define packet_add(p, data) \
@@ -43,9 +46,13 @@ void pool_flush(struct pool *p);
#define packet_get(p, idx, offset, len, left) \
packet_get_do(p, idx, offset, len, left, __func__, __LINE__)
+
#define packet_get_try(p, idx, offset, len, left) \
packet_get_do(p, idx, offset, len, left, NULL, 0)
+#define packet_base(p, idx, data) \
+ packet_base_do(p, idx, data, __func__, __LINE__)
+
#define PACKET_POOL_DECL(_name, _size, _buf) \
struct _name ## _t { \
char *buf; \
--
@@ -35,6 +35,9 @@ void packet_add_do(struct pool *p, struct iov_tail *data,
void *packet_get_do(const struct pool *p, const size_t idx,
size_t offset, size_t len, size_t *left,
const char *func, int line);
+bool packet_base_do(const struct pool *p, const size_t idx,
+ struct iov_tail *data,
+ const char *func, int line);
void pool_flush(struct pool *p);
#define packet_add(p, data) \
@@ -43,9 +46,13 @@ void pool_flush(struct pool *p);
#define packet_get(p, idx, offset, len, left) \
packet_get_do(p, idx, offset, len, left, __func__, __LINE__)
+
#define packet_get_try(p, idx, offset, len, left) \
packet_get_do(p, idx, offset, len, left, NULL, 0)
+#define packet_base(p, idx, data) \
+ packet_base_do(p, idx, data, __func__, __LINE__)
+
#define PACKET_POOL_DECL(_name, _size, _buf) \
struct _name ## _t { \
char *buf; \
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 06/18] arp: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (4 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 05/18] packet: Add packet_base() Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:00 ` David Gibson
2025-04-02 17:23 ` [PATCH 07/18] ndp: " Laurent Vivier
` (11 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
arp.c | 12 +++++++++---
packet.c | 1 -
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/arp.c b/arp.c
index 9d68d7c3b602..cd0e15de7de0 100644
--- a/arp.c
+++ b/arp.c
@@ -77,11 +77,17 @@ int arp(const struct ctx *c, const struct pool *p)
const struct ethhdr *eh;
const struct arphdr *ah;
const struct arpmsg *am;
+ struct iov_tail data;
+ struct arphdr ahc;
+ struct ethhdr ehc;
+ struct arpmsg amc;
- eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
- ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
- am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
+ if (!packet_base(p, 0, &data))
+ return -1;
+ eh = IOV_REMOVE_HEADER(&data, ehc);
+ ah = IOV_REMOVE_HEADER(&data, ahc);
+ am = IOV_REMOVE_HEADER(&data, amc);
if (!eh || !ah || !am)
return -1;
diff --git a/packet.c b/packet.c
index 25ede38b94cb..8066ac12502b 100644
--- a/packet.c
+++ b/packet.c
@@ -165,7 +165,6 @@ void *packet_get_do(const struct pool *p, size_t idx, size_t offset,
*
* Return: pointer to start of data range, NULL on invalid range or descriptor
*/
-/* cppcheck-suppress unusedFunction */
bool packet_base_do(const struct pool *p, size_t idx,
struct iov_tail *data,
const char *func, int line)
--
@@ -165,7 +165,6 @@ void *packet_get_do(const struct pool *p, size_t idx, size_t offset,
*
* Return: pointer to start of data range, NULL on invalid range or descriptor
*/
-/* cppcheck-suppress unusedFunction */
bool packet_base_do(const struct pool *p, size_t idx,
struct iov_tail *data,
const char *func, int line)
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 07/18] ndp: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (5 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 06/18] arp: Convert to iov_tail Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:01 ` David Gibson
2025-04-02 17:23 ` [PATCH 08/18] icmp: " Laurent Vivier
` (10 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
ndp.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/ndp.c b/ndp.c
index ded2081ddd1d..64e25d5455b4 100644
--- a/ndp.c
+++ b/ndp.c
@@ -351,8 +351,13 @@ int ndp(const struct ctx *c, const struct icmp6hdr *ih,
if (ih->icmp6_type == NS) {
const struct ndp_ns *ns;
+ struct iov_tail data;
+ struct ndp_ns nsc;
- ns = packet_get(p, 0, 0, sizeof(struct ndp_ns), NULL);
+ if (!packet_base(p, 0, &data))
+ return -1;
+
+ ns = IOV_REMOVE_HEADER(&data, nsc);
if (!ns)
return -1;
--
@@ -351,8 +351,13 @@ int ndp(const struct ctx *c, const struct icmp6hdr *ih,
if (ih->icmp6_type == NS) {
const struct ndp_ns *ns;
+ struct iov_tail data;
+ struct ndp_ns nsc;
- ns = packet_get(p, 0, 0, sizeof(struct ndp_ns), NULL);
+ if (!packet_base(p, 0, &data))
+ return -1;
+
+ ns = IOV_REMOVE_HEADER(&data, nsc);
if (!ns)
return -1;
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 08/18] icmp: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (6 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 07/18] ndp: " Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:04 ` David Gibson
2025-04-02 17:23 ` [PATCH 09/18] udp: " Laurent Vivier
` (9 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_PEEK_HEADER()
rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
icmp.c | 38 +++++++++++++++++++++++---------------
1 file changed, 23 insertions(+), 15 deletions(-)
diff --git a/icmp.c b/icmp.c
index 7e2b3423a8d1..119502c0c340 100644
--- a/icmp.c
+++ b/icmp.c
@@ -241,24 +241,25 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
struct icmp_ping_flow *pingf;
const struct flowside *tgt;
union sockaddr_inany sa;
- size_t dlen, l4len;
+ struct iov_tail data;
+ struct msghdr msh;
uint16_t id, seq;
union flow *flow;
uint8_t proto;
- socklen_t sl;
- void *pkt;
(void)saddr;
ASSERT(pif == PIF_TAP);
+ if (!packet_base(p, 0, &data))
+ return -1;
+
if (af == AF_INET) {
const struct icmphdr *ih;
+ struct icmphdr ihc;
- if (!(pkt = packet_get(p, 0, 0, sizeof(*ih), &dlen)))
- return 1;
-
- ih = (struct icmphdr *)pkt;
- l4len = dlen + sizeof(*ih);
+ ih = IOV_PEEK_HEADER(&data, ihc);
+ if (!ih)
+ return -1;
if (ih->type != ICMP_ECHO)
return 1;
@@ -268,12 +269,11 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
seq = ntohs(ih->un.echo.sequence);
} else if (af == AF_INET6) {
const struct icmp6hdr *ih;
+ struct icmp6hdr ihc;
- if (!(pkt = packet_get(p, 0, 0, sizeof(*ih), &dlen)))
- return 1;
-
- ih = (struct icmp6hdr *)pkt;
- l4len = dlen + sizeof(*ih);
+ ih = IOV_PEEK_HEADER(&data, ihc);
+ if (!ih)
+ return -1;
if (ih->icmp6_type != ICMPV6_ECHO_REQUEST)
return 1;
@@ -298,8 +298,16 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
ASSERT(flow_proto[pingf->f.type] == proto);
pingf->ts = now->tv_sec;
- pif_sockaddr(c, &sa, &sl, PIF_HOST, &tgt->eaddr, 0);
- if (sendto(pingf->sock, pkt, l4len, MSG_NOSIGNAL, &sa.sa, sl) < 0) {
+ ASSERT(data.off == 0);
+ msh.msg_name = &sa;
+ msh.msg_iov = (struct iovec *)data.iov;
+ msh.msg_iovlen = data.cnt;
+ msh.msg_control = NULL;
+ msh.msg_controllen = 0;
+ msh.msg_flags = 0;
+
+ pif_sockaddr(c, &sa, &msh.msg_namelen, PIF_HOST, &tgt->eaddr, 0);
+ if (sendmsg(pingf->sock, &msh, MSG_NOSIGNAL) < 0) {
flow_dbg_perror(pingf, "failed to relay request to socket");
} else {
flow_dbg(pingf,
--
@@ -241,24 +241,25 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
struct icmp_ping_flow *pingf;
const struct flowside *tgt;
union sockaddr_inany sa;
- size_t dlen, l4len;
+ struct iov_tail data;
+ struct msghdr msh;
uint16_t id, seq;
union flow *flow;
uint8_t proto;
- socklen_t sl;
- void *pkt;
(void)saddr;
ASSERT(pif == PIF_TAP);
+ if (!packet_base(p, 0, &data))
+ return -1;
+
if (af == AF_INET) {
const struct icmphdr *ih;
+ struct icmphdr ihc;
- if (!(pkt = packet_get(p, 0, 0, sizeof(*ih), &dlen)))
- return 1;
-
- ih = (struct icmphdr *)pkt;
- l4len = dlen + sizeof(*ih);
+ ih = IOV_PEEK_HEADER(&data, ihc);
+ if (!ih)
+ return -1;
if (ih->type != ICMP_ECHO)
return 1;
@@ -268,12 +269,11 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
seq = ntohs(ih->un.echo.sequence);
} else if (af == AF_INET6) {
const struct icmp6hdr *ih;
+ struct icmp6hdr ihc;
- if (!(pkt = packet_get(p, 0, 0, sizeof(*ih), &dlen)))
- return 1;
-
- ih = (struct icmp6hdr *)pkt;
- l4len = dlen + sizeof(*ih);
+ ih = IOV_PEEK_HEADER(&data, ihc);
+ if (!ih)
+ return -1;
if (ih->icmp6_type != ICMPV6_ECHO_REQUEST)
return 1;
@@ -298,8 +298,16 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
ASSERT(flow_proto[pingf->f.type] == proto);
pingf->ts = now->tv_sec;
- pif_sockaddr(c, &sa, &sl, PIF_HOST, &tgt->eaddr, 0);
- if (sendto(pingf->sock, pkt, l4len, MSG_NOSIGNAL, &sa.sa, sl) < 0) {
+ ASSERT(data.off == 0);
+ msh.msg_name = &sa;
+ msh.msg_iov = (struct iovec *)data.iov;
+ msh.msg_iovlen = data.cnt;
+ msh.msg_control = NULL;
+ msh.msg_controllen = 0;
+ msh.msg_flags = 0;
+
+ pif_sockaddr(c, &sa, &msh.msg_namelen, PIF_HOST, &tgt->eaddr, 0);
+ if (sendmsg(pingf->sock, &msh, MSG_NOSIGNAL) < 0) {
flow_dbg_perror(pingf, "failed to relay request to socket");
} else {
flow_dbg(pingf,
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 09/18] udp: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (7 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 08/18] icmp: " Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:11 ` David Gibson
2025-04-02 17:23 ` [PATCH 10/18] tcp: Convert tcp_tap_handler() to use iov_tail Laurent Vivier
` (8 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
and IOV_PEEK_HEADER() rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
iov.c | 1 -
udp.c | 37 ++++++++++++++++++++++++++-----------
2 files changed, 26 insertions(+), 12 deletions(-)
diff --git a/iov.c b/iov.c
index 508fb6da91fb..0c69379316aa 100644
--- a/iov.c
+++ b/iov.c
@@ -173,7 +173,6 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt)
* Returns: The number of elements successfully copied to the destination
* iov array.
*/
-/* cppcheck-suppress unusedFunction */
unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
const struct iovec *iov, size_t iov_cnt,
size_t offset, size_t bytes)
diff --git a/udp.c b/udp.c
index 80520cbdf188..03906d72e75c 100644
--- a/udp.c
+++ b/udp.c
@@ -858,15 +858,20 @@ int udp_tap_handler(const struct ctx *c, uint8_t pif,
struct iovec m[UIO_MAXIOV];
const struct udphdr *uh;
struct udp_flow *uflow;
- int i, s, count = 0;
+ int i, j, s, count = 0;
+ struct iov_tail data;
flow_sidx_t tosidx;
in_port_t src, dst;
+ struct udphdr uhc;
uint8_t topif;
socklen_t sl;
ASSERT(!c->no_udp);
- uh = packet_get(p, idx, 0, sizeof(*uh), NULL);
+ if (!packet_base(p, idx, &data))
+ return 1;
+
+ uh = IOV_PEEK_HEADER(&data, uhc);
if (!uh)
return 1;
@@ -903,23 +908,33 @@ int udp_tap_handler(const struct ctx *c, uint8_t pif,
pif_sockaddr(c, &to_sa, &sl, topif, &toside->eaddr, toside->eport);
- for (i = 0; i < (int)p->count - idx; i++) {
- struct udphdr *uh_send;
- size_t len;
+ for (i = 0, j = 0; i < (int)p->count - idx && j < UIO_MAXIOV; i++) {
+ const struct udphdr *uh_send;
+
+ if (!packet_base(p, idx + i, &data))
+ return p->count - idx;
- uh_send = packet_get(p, idx + i, 0, sizeof(*uh), &len);
+ uh_send = IOV_REMOVE_HEADER(&data, uhc);
if (!uh_send)
return p->count - idx;
+ iov_tail_prune(&data);
+
+ if (data.cnt + j >= UIO_MAXIOV)
+ return p->count - idx;
+
mm[i].msg_hdr.msg_name = &to_sa;
mm[i].msg_hdr.msg_namelen = sl;
- if (len) {
- m[i].iov_base = (char *)(uh_send + 1);
- m[i].iov_len = len;
+ if (data.cnt ) {
+ unsigned int len;
+
+ len = iov_copy(&m[j], UIO_MAXIOV - j,
+ &data.iov[0], data.cnt, data.off, SIZE_MAX);
- mm[i].msg_hdr.msg_iov = m + i;
- mm[i].msg_hdr.msg_iovlen = 1;
+ mm[i].msg_hdr.msg_iov = &m[j];
+ mm[i].msg_hdr.msg_iovlen = len;
+ j += len;
} else {
mm[i].msg_hdr.msg_iov = NULL;
mm[i].msg_hdr.msg_iovlen = 0;
--
@@ -858,15 +858,20 @@ int udp_tap_handler(const struct ctx *c, uint8_t pif,
struct iovec m[UIO_MAXIOV];
const struct udphdr *uh;
struct udp_flow *uflow;
- int i, s, count = 0;
+ int i, j, s, count = 0;
+ struct iov_tail data;
flow_sidx_t tosidx;
in_port_t src, dst;
+ struct udphdr uhc;
uint8_t topif;
socklen_t sl;
ASSERT(!c->no_udp);
- uh = packet_get(p, idx, 0, sizeof(*uh), NULL);
+ if (!packet_base(p, idx, &data))
+ return 1;
+
+ uh = IOV_PEEK_HEADER(&data, uhc);
if (!uh)
return 1;
@@ -903,23 +908,33 @@ int udp_tap_handler(const struct ctx *c, uint8_t pif,
pif_sockaddr(c, &to_sa, &sl, topif, &toside->eaddr, toside->eport);
- for (i = 0; i < (int)p->count - idx; i++) {
- struct udphdr *uh_send;
- size_t len;
+ for (i = 0, j = 0; i < (int)p->count - idx && j < UIO_MAXIOV; i++) {
+ const struct udphdr *uh_send;
+
+ if (!packet_base(p, idx + i, &data))
+ return p->count - idx;
- uh_send = packet_get(p, idx + i, 0, sizeof(*uh), &len);
+ uh_send = IOV_REMOVE_HEADER(&data, uhc);
if (!uh_send)
return p->count - idx;
+ iov_tail_prune(&data);
+
+ if (data.cnt + j >= UIO_MAXIOV)
+ return p->count - idx;
+
mm[i].msg_hdr.msg_name = &to_sa;
mm[i].msg_hdr.msg_namelen = sl;
- if (len) {
- m[i].iov_base = (char *)(uh_send + 1);
- m[i].iov_len = len;
+ if (data.cnt ) {
+ unsigned int len;
+
+ len = iov_copy(&m[j], UIO_MAXIOV - j,
+ &data.iov[0], data.cnt, data.off, SIZE_MAX);
- mm[i].msg_hdr.msg_iov = m + i;
- mm[i].msg_hdr.msg_iovlen = 1;
+ mm[i].msg_hdr.msg_iov = &m[j];
+ mm[i].msg_hdr.msg_iovlen = len;
+ j += len;
} else {
mm[i].msg_hdr.msg_iov = NULL;
mm[i].msg_hdr.msg_iovlen = 0;
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 10/18] tcp: Convert tcp_tap_handler() to use iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (8 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 09/18] udp: " Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:14 ` David Gibson
2025-04-02 17:23 ` [PATCH 11/18] tcp: Convert tcp_data_from_tap() " Laurent Vivier
` (7 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
and iov_peek_header_() rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
tcp.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)
diff --git a/tcp.c b/tcp.c
index a4c840e6721c..790714a08793 100644
--- a/tcp.c
+++ b/tcp.c
@@ -310,6 +310,8 @@
#include "tcp_buf.h"
#include "tcp_vu.h"
+#define OPTLEN_MAX (((1UL << 4) - 6) * 4UL)
+
#ifndef __USE_MISC
/* From Linux UAPI, missing in netinet/tcp.h provided by musl */
struct tcp_repair_opt {
@@ -1957,7 +1959,10 @@ int tcp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
{
struct tcp_tap_conn *conn;
const struct tcphdr *th;
+ char optsc[OPTLEN_MAX];
+ struct iov_tail data;
size_t optlen, len;
+ struct tcphdr thc;
const char *opts;
union flow *flow;
flow_sidx_t sidx;
@@ -1966,15 +1971,19 @@ int tcp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
(void)pif;
- th = packet_get(p, idx, 0, sizeof(*th), &len);
+ if (!packet_base(p, idx, &data))
+ return 1;
+
+ len = iov_tail_size(&data);
+
+ th = IOV_REMOVE_HEADER(&data, thc);
if (!th)
return 1;
- len += sizeof(*th);
optlen = th->doff * 4UL - sizeof(*th);
/* Static checkers might fail to see this: */
- optlen = MIN(optlen, ((1UL << 4) /* from doff width */ - 6) * 4UL);
- opts = packet_get(p, idx, sizeof(*th), optlen, NULL);
+ optlen = MIN(optlen, OPTLEN_MAX);
+ opts = (char *)iov_peek_header_(&data, &optsc[0], optlen, 1);
sidx = flow_lookup_af(c, IPPROTO_TCP, PIF_TAP, af, saddr, daddr,
ntohs(th->source), ntohs(th->dest));
--
@@ -310,6 +310,8 @@
#include "tcp_buf.h"
#include "tcp_vu.h"
+#define OPTLEN_MAX (((1UL << 4) - 6) * 4UL)
+
#ifndef __USE_MISC
/* From Linux UAPI, missing in netinet/tcp.h provided by musl */
struct tcp_repair_opt {
@@ -1957,7 +1959,10 @@ int tcp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
{
struct tcp_tap_conn *conn;
const struct tcphdr *th;
+ char optsc[OPTLEN_MAX];
+ struct iov_tail data;
size_t optlen, len;
+ struct tcphdr thc;
const char *opts;
union flow *flow;
flow_sidx_t sidx;
@@ -1966,15 +1971,19 @@ int tcp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
(void)pif;
- th = packet_get(p, idx, 0, sizeof(*th), &len);
+ if (!packet_base(p, idx, &data))
+ return 1;
+
+ len = iov_tail_size(&data);
+
+ th = IOV_REMOVE_HEADER(&data, thc);
if (!th)
return 1;
- len += sizeof(*th);
optlen = th->doff * 4UL - sizeof(*th);
/* Static checkers might fail to see this: */
- optlen = MIN(optlen, ((1UL << 4) /* from doff width */ - 6) * 4UL);
- opts = packet_get(p, idx, sizeof(*th), optlen, NULL);
+ optlen = MIN(optlen, OPTLEN_MAX);
+ opts = (char *)iov_peek_header_(&data, &optsc[0], optlen, 1);
sidx = flow_lookup_af(c, IPPROTO_TCP, PIF_TAP, af, saddr, daddr,
ntohs(th->source), ntohs(th->dest));
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 11/18] tcp: Convert tcp_data_from_tap() to use iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (9 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 10/18] tcp: Convert tcp_tap_handler() to use iov_tail Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:20 ` David Gibson
2025-04-02 17:23 ` [PATCH 12/18] dhcpv6: Convert to iov_tail Laurent Vivier
` (6 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_PEEK_HEADER()
rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
tcp.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/tcp.c b/tcp.c
index 790714a08793..a9c04551d9d6 100644
--- a/tcp.c
+++ b/tcp.c
@@ -1643,14 +1643,19 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
for (i = idx, iov_i = 0; i < (int)p->count; i++) {
uint32_t seq, seq_offset, ack_seq;
const struct tcphdr *th;
- char *data;
+ struct iov_tail data;
+ unsigned int count;
+ struct tcphdr thc;
size_t off;
- th = packet_get(p, i, 0, sizeof(*th), &len);
+ if (!packet_base(p, i, &data))
+ return -1;
+
+ th = IOV_PEEK_HEADER(&data, thc);
if (!th)
return -1;
- len += sizeof(*th);
+ len = iov_tail_size(&data);
off = th->doff * 4UL;
if (off < sizeof(*th) || off > len)
return -1;
@@ -1661,9 +1666,7 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
}
len -= off;
- data = packet_get(p, i, off, len, NULL);
- if (!data)
- continue;
+ data.off = off;
seq = ntohl(th->seq);
if (SEQ_LT(seq, conn->seq_from_tap) && len <= 1) {
@@ -1737,10 +1740,11 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
continue;
}
- tcp_iov[iov_i].iov_base = data + seq_offset;
- tcp_iov[iov_i].iov_len = len - seq_offset;
- seq_from_tap += tcp_iov[iov_i].iov_len;
- iov_i++;
+ count = iov_copy(&tcp_iov[iov_i], UIO_MAXIOV - iov_i,
+ &data.iov[0], data.cnt, data.off + seq_offset,
+ len - seq_offset);
+ seq_from_tap += iov_size(&tcp_iov[iov_i], count);
+ iov_i += count;
if (keep == i)
keep = -1;
--
@@ -1643,14 +1643,19 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
for (i = idx, iov_i = 0; i < (int)p->count; i++) {
uint32_t seq, seq_offset, ack_seq;
const struct tcphdr *th;
- char *data;
+ struct iov_tail data;
+ unsigned int count;
+ struct tcphdr thc;
size_t off;
- th = packet_get(p, i, 0, sizeof(*th), &len);
+ if (!packet_base(p, i, &data))
+ return -1;
+
+ th = IOV_PEEK_HEADER(&data, thc);
if (!th)
return -1;
- len += sizeof(*th);
+ len = iov_tail_size(&data);
off = th->doff * 4UL;
if (off < sizeof(*th) || off > len)
return -1;
@@ -1661,9 +1666,7 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
}
len -= off;
- data = packet_get(p, i, off, len, NULL);
- if (!data)
- continue;
+ data.off = off;
seq = ntohl(th->seq);
if (SEQ_LT(seq, conn->seq_from_tap) && len <= 1) {
@@ -1737,10 +1740,11 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
continue;
}
- tcp_iov[iov_i].iov_base = data + seq_offset;
- tcp_iov[iov_i].iov_len = len - seq_offset;
- seq_from_tap += tcp_iov[iov_i].iov_len;
- iov_i++;
+ count = iov_copy(&tcp_iov[iov_i], UIO_MAXIOV - iov_i,
+ &data.iov[0], data.cnt, data.off + seq_offset,
+ len - seq_offset);
+ seq_from_tap += iov_size(&tcp_iov[iov_i], count);
+ iov_i += count;
if (keep == i)
keep = -1;
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 12/18] dhcpv6: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (10 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 11/18] tcp: Convert tcp_data_from_tap() " Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:21 ` David Gibson
2025-04-02 17:23 ` [PATCH 13/18] dhcpv6: move offset initialization out of dhcpv6_opt() Laurent Vivier
` (5 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
and IOV_PEEK_HEADER() rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
dhcpv6.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/dhcpv6.c b/dhcpv6.c
index 373a98869f9b..eb3f188af0b5 100644
--- a/dhcpv6.c
+++ b/dhcpv6.c
@@ -496,9 +496,15 @@ int dhcpv6(struct ctx *c, const struct pool *p,
const struct msg_hdr *mh;
const struct udphdr *uh;
struct opt_hdr *bad_ia;
+ struct iov_tail data;
+ struct msg_hdr mhc;
+ struct udphdr uhc;
size_t mlen, n;
- uh = packet_get(p, 0, 0, sizeof(*uh), &mlen);
+ if (!packet_base(p, 0, &data))
+ return -1;
+
+ uh = IOV_REMOVE_HEADER(&data, uhc);
if (!uh)
return -1;
@@ -511,6 +517,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
if (!IN6_IS_ADDR_MULTICAST(daddr))
return -1;
+ mlen = iov_tail_size(&data);
if (mlen + sizeof(*uh) != ntohs(uh->len) || mlen < sizeof(*mh))
return -1;
@@ -518,7 +525,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
src = &c->ip6.our_tap_ll;
- mh = packet_get(p, 0, sizeof(*uh), sizeof(*mh), NULL);
+ mh = IOV_PEEK_HEADER(&data, mhc);
if (!mh)
return -1;
--
@@ -496,9 +496,15 @@ int dhcpv6(struct ctx *c, const struct pool *p,
const struct msg_hdr *mh;
const struct udphdr *uh;
struct opt_hdr *bad_ia;
+ struct iov_tail data;
+ struct msg_hdr mhc;
+ struct udphdr uhc;
size_t mlen, n;
- uh = packet_get(p, 0, 0, sizeof(*uh), &mlen);
+ if (!packet_base(p, 0, &data))
+ return -1;
+
+ uh = IOV_REMOVE_HEADER(&data, uhc);
if (!uh)
return -1;
@@ -511,6 +517,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
if (!IN6_IS_ADDR_MULTICAST(daddr))
return -1;
+ mlen = iov_tail_size(&data);
if (mlen + sizeof(*uh) != ntohs(uh->len) || mlen < sizeof(*mh))
return -1;
@@ -518,7 +525,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
src = &c->ip6.our_tap_ll;
- mh = packet_get(p, 0, sizeof(*uh), sizeof(*mh), NULL);
+ mh = IOV_PEEK_HEADER(&data, mhc);
if (!mh)
return -1;
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 13/18] dhcpv6: move offset initialization out of dhcpv6_opt()
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (11 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 12/18] dhcpv6: Convert to iov_tail Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:25 ` David Gibson
2025-04-02 17:23 ` [PATCH 14/18] dhcpv6: Use iov_tail in dhcpv6_opt() Laurent Vivier
` (4 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
dhcpv6.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/dhcpv6.c b/dhcpv6.c
index eb3f188af0b5..ccc64172a480 100644
--- a/dhcpv6.c
+++ b/dhcpv6.c
@@ -54,14 +54,14 @@ struct opt_hdr {
uint16_t l;
} __attribute__((packed));
+#define UDP_MSG_HDR_SIZE (sizeof(struct udphdr) + sizeof(struct msg_hdr))
# define OPT_SIZE_CONV(x) (htons_constant(x))
#define OPT_SIZE(x) OPT_SIZE_CONV(sizeof(struct opt_##x) - \
sizeof(struct opt_hdr))
#define OPT_VSIZE(x) (sizeof(struct opt_##x) - \
sizeof(struct opt_hdr))
#define OPT_MAX_SIZE IPV6_MIN_MTU - (sizeof(struct ipv6hdr) + \
- sizeof(struct udphdr) + \
- sizeof(struct msg_hdr))
+ UDP_MSG_HDR_SIZE)
/**
* struct opt_client_id - DHCPv6 Client Identifier option
@@ -290,8 +290,7 @@ static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
struct opt_hdr *o;
size_t left;
- if (!*offset)
- *offset = sizeof(struct udphdr) + sizeof(struct msg_hdr);
+ ASSERT(*offset >= UDP_MSG_HDR_SIZE);
while ((o = packet_get_try(p, 0, *offset, sizeof(*o), &left))) {
unsigned int opt_len = ntohs(o->l) + sizeof(*o);
@@ -327,7 +326,7 @@ static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
size_t offset;
foreach(ia_type, ia_types) {
- offset = 0;
+ offset = UDP_MSG_HDR_SIZE;
while ((ia = dhcpv6_opt(p, &offset, *ia_type))) {
if (ntohs(ia->l) < OPT_VSIZE(ia_na))
return NULL;
@@ -464,8 +463,9 @@ static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
o = (struct opt_client_fqdn *)(buf + offset);
encode_domain_name(o->domain_name, c->fqdn);
- req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p, &(size_t){ 0 },
- OPT_CLIENT_FQDN);
+ req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p,
+ &(size_t){ UDP_MSG_HDR_SIZE },
+ OPT_CLIENT_FQDN);
if (req_opt && req_opt->flags & 0x01 /* S flag */)
o->flags = 0x02 /* O flag */;
else
@@ -529,15 +529,15 @@ int dhcpv6(struct ctx *c, const struct pool *p,
if (!mh)
return -1;
- client_id = dhcpv6_opt(p, &(size_t){ 0 }, OPT_CLIENTID);
+ client_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_CLIENTID);
if (!client_id || ntohs(client_id->l) > OPT_VSIZE(client_id))
return -1;
- server_id = dhcpv6_opt(p, &(size_t){ 0 }, OPT_SERVERID);
+ server_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_SERVERID);
if (server_id && ntohs(server_id->l) != OPT_VSIZE(server_id))
return -1;
- ia = dhcpv6_opt(p, &(size_t){ 0 }, OPT_IA_NA);
+ ia = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_NA);
if (ia && ntohs(ia->l) < MIN(OPT_VSIZE(ia_na), OPT_VSIZE(ia_ta)))
return -1;
@@ -587,7 +587,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
memcmp(&resp.server_id, server_id, sizeof(resp.server_id)))
return -1;
- if (ia || dhcpv6_opt(p, &(size_t){ 0 }, OPT_IA_TA))
+ if (ia || dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_TA))
return -1;
info("DHCPv6: received INFORMATION_REQUEST, sending REPLY");
--
@@ -54,14 +54,14 @@ struct opt_hdr {
uint16_t l;
} __attribute__((packed));
+#define UDP_MSG_HDR_SIZE (sizeof(struct udphdr) + sizeof(struct msg_hdr))
# define OPT_SIZE_CONV(x) (htons_constant(x))
#define OPT_SIZE(x) OPT_SIZE_CONV(sizeof(struct opt_##x) - \
sizeof(struct opt_hdr))
#define OPT_VSIZE(x) (sizeof(struct opt_##x) - \
sizeof(struct opt_hdr))
#define OPT_MAX_SIZE IPV6_MIN_MTU - (sizeof(struct ipv6hdr) + \
- sizeof(struct udphdr) + \
- sizeof(struct msg_hdr))
+ UDP_MSG_HDR_SIZE)
/**
* struct opt_client_id - DHCPv6 Client Identifier option
@@ -290,8 +290,7 @@ static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
struct opt_hdr *o;
size_t left;
- if (!*offset)
- *offset = sizeof(struct udphdr) + sizeof(struct msg_hdr);
+ ASSERT(*offset >= UDP_MSG_HDR_SIZE);
while ((o = packet_get_try(p, 0, *offset, sizeof(*o), &left))) {
unsigned int opt_len = ntohs(o->l) + sizeof(*o);
@@ -327,7 +326,7 @@ static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
size_t offset;
foreach(ia_type, ia_types) {
- offset = 0;
+ offset = UDP_MSG_HDR_SIZE;
while ((ia = dhcpv6_opt(p, &offset, *ia_type))) {
if (ntohs(ia->l) < OPT_VSIZE(ia_na))
return NULL;
@@ -464,8 +463,9 @@ static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
o = (struct opt_client_fqdn *)(buf + offset);
encode_domain_name(o->domain_name, c->fqdn);
- req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p, &(size_t){ 0 },
- OPT_CLIENT_FQDN);
+ req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p,
+ &(size_t){ UDP_MSG_HDR_SIZE },
+ OPT_CLIENT_FQDN);
if (req_opt && req_opt->flags & 0x01 /* S flag */)
o->flags = 0x02 /* O flag */;
else
@@ -529,15 +529,15 @@ int dhcpv6(struct ctx *c, const struct pool *p,
if (!mh)
return -1;
- client_id = dhcpv6_opt(p, &(size_t){ 0 }, OPT_CLIENTID);
+ client_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_CLIENTID);
if (!client_id || ntohs(client_id->l) > OPT_VSIZE(client_id))
return -1;
- server_id = dhcpv6_opt(p, &(size_t){ 0 }, OPT_SERVERID);
+ server_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_SERVERID);
if (server_id && ntohs(server_id->l) != OPT_VSIZE(server_id))
return -1;
- ia = dhcpv6_opt(p, &(size_t){ 0 }, OPT_IA_NA);
+ ia = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_NA);
if (ia && ntohs(ia->l) < MIN(OPT_VSIZE(ia_na), OPT_VSIZE(ia_ta)))
return -1;
@@ -587,7 +587,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
memcmp(&resp.server_id, server_id, sizeof(resp.server_id)))
return -1;
- if (ia || dhcpv6_opt(p, &(size_t){ 0 }, OPT_IA_TA))
+ if (ia || dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_TA))
return -1;
info("DHCPv6: received INFORMATION_REQUEST, sending REPLY");
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 14/18] dhcpv6: Use iov_tail in dhcpv6_opt()
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (12 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 13/18] dhcpv6: move offset initialization out of dhcpv6_opt() Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:37 ` David Gibson
2025-04-02 17:23 ` [PATCH 15/18] dhcp: Convert to iov_tail Laurent Vivier
` (3 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
dhcpv6.c | 57 +++++++++++++++++++++++++++-----------------------------
1 file changed, 27 insertions(+), 30 deletions(-)
diff --git a/dhcpv6.c b/dhcpv6.c
index ccc64172a480..1e83f2c2ad23 100644
--- a/dhcpv6.c
+++ b/dhcpv6.c
@@ -278,30 +278,25 @@ static struct resp_not_on_link_t {
/**
* dhcpv6_opt() - Get option from DHCPv6 message
- * @p: Packet pool, single packet with UDP header
- * @offset: Offset to look at, 0: end of header, set to option start
+ * @data: Data to look at
* @type: Option type to look up, network order
*
* Return: pointer to option header, or NULL on malformed or missing option
*/
-static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
- uint16_t type)
+static struct opt_hdr *dhcpv6_opt(struct iov_tail *data, uint16_t type)
{
- struct opt_hdr *o;
- size_t left;
+ struct opt_hdr *o, oc;
- ASSERT(*offset >= UDP_MSG_HDR_SIZE);
-
- while ((o = packet_get_try(p, 0, *offset, sizeof(*o), &left))) {
+ while ((o = IOV_PEEK_HEADER(data, oc))) {
unsigned int opt_len = ntohs(o->l) + sizeof(*o);
- if (ntohs(o->l) > left)
+ if (opt_len > iov_tail_size(data))
return NULL;
if (o->t == type)
return o;
- *offset += opt_len;
+ data->off += opt_len;
}
return NULL;
@@ -309,31 +304,31 @@ static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
/**
* dhcpv6_ia_notonlink() - Check if any IA contains non-appropriate addresses
- * @p: Packet pool, single packet starting from UDP header
+ * @data: Data to look at, packet starting from UDP header
* @la: Address we want to lease to the client
*
* Return: pointer to non-appropriate IA_NA or IA_TA, if any, NULL otherwise
*/
-static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
+static struct opt_hdr *dhcpv6_ia_notonlink(const struct iov_tail *data,
struct in6_addr *la)
{
int ia_types[2] = { OPT_IA_NA, OPT_IA_TA }, *ia_type;
const struct opt_ia_addr *opt_addr;
char buf[INET6_ADDRSTRLEN];
struct in6_addr req_addr;
+ struct iov_tail current;
const struct opt_hdr *h;
struct opt_hdr *ia;
- size_t offset;
foreach(ia_type, ia_types) {
- offset = UDP_MSG_HDR_SIZE;
- while ((ia = dhcpv6_opt(p, &offset, *ia_type))) {
+ current = *data;
+ while ((ia = dhcpv6_opt(¤t, *ia_type))) {
if (ntohs(ia->l) < OPT_VSIZE(ia_na))
return NULL;
- offset += sizeof(struct opt_ia_na);
+ current.off += sizeof(struct opt_ia_na);
- while ((h = dhcpv6_opt(p, &offset, OPT_IAAADR))) {
+ while ((h = dhcpv6_opt(¤t, OPT_IAAADR))) {
if (ntohs(h->l) != OPT_VSIZE(ia_addr))
return NULL;
@@ -342,7 +337,7 @@ static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
if (!IN6_ARE_ADDR_EQUAL(la, &req_addr))
goto err;
- offset += sizeof(struct opt_ia_addr);
+ current.off += sizeof(struct opt_ia_addr);
}
}
}
@@ -434,13 +429,15 @@ search:
/**
* dhcpv6_client_fqdn_fill() - Fill in client FQDN option
+ * @data: Data to look at
* @c: Execution context
* @buf: Response message buffer where options will be appended
* @offset: Offset in message buffer for new options
*
* Return: updated length of response message buffer.
*/
-static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
+static size_t dhcpv6_client_fqdn_fill(struct iov_tail *data,
+ const struct ctx *c,
char *buf, int offset)
{
@@ -463,9 +460,8 @@ static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
o = (struct opt_client_fqdn *)(buf + offset);
encode_domain_name(o->domain_name, c->fqdn);
- req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p,
- &(size_t){ UDP_MSG_HDR_SIZE },
- OPT_CLIENT_FQDN);
+ data->off += UDP_MSG_HDR_SIZE;
+ req_opt = (struct opt_client_fqdn *)dhcpv6_opt(data, OPT_CLIENT_FQDN);
if (req_opt && req_opt->flags & 0x01 /* S flag */)
o->flags = 0x02 /* O flag */;
else
@@ -525,19 +521,19 @@ int dhcpv6(struct ctx *c, const struct pool *p,
src = &c->ip6.our_tap_ll;
- mh = IOV_PEEK_HEADER(&data, mhc);
+ mh = IOV_REMOVE_HEADER(&data, mhc);
if (!mh)
return -1;
- client_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_CLIENTID);
+ client_id = dhcpv6_opt(&data, OPT_CLIENTID);
if (!client_id || ntohs(client_id->l) > OPT_VSIZE(client_id))
return -1;
- server_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_SERVERID);
+ server_id = dhcpv6_opt(&data, OPT_SERVERID);
if (server_id && ntohs(server_id->l) != OPT_VSIZE(server_id))
return -1;
- ia = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_NA);
+ ia = dhcpv6_opt(&data, OPT_IA_NA);
if (ia && ntohs(ia->l) < MIN(OPT_VSIZE(ia_na), OPT_VSIZE(ia_ta)))
return -1;
@@ -553,7 +549,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
if (mh->type == TYPE_CONFIRM && server_id)
return -1;
- if ((bad_ia = dhcpv6_ia_notonlink(p, &c->ip6.addr))) {
+ if ((bad_ia = dhcpv6_ia_notonlink(&data, &c->ip6.addr))) {
info("DHCPv6: received CONFIRM with inappropriate IA,"
" sending NotOnLink status in REPLY");
@@ -587,7 +583,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
memcmp(&resp.server_id, server_id, sizeof(resp.server_id)))
return -1;
- if (ia || dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_TA))
+ if (ia || dhcpv6_opt(&data, OPT_IA_TA))
return -1;
info("DHCPv6: received INFORMATION_REQUEST, sending REPLY");
@@ -619,7 +615,8 @@ int dhcpv6(struct ctx *c, const struct pool *p,
n = offsetof(struct resp_t, client_id) +
sizeof(struct opt_hdr) + ntohs(client_id->l);
n = dhcpv6_dns_fill(c, (char *)&resp, n);
- n = dhcpv6_client_fqdn_fill(p, c, (char *)&resp, n);
+ packet_base(p, 0, &data);
+ n = dhcpv6_client_fqdn_fill(&data, c, (char *)&resp, n);
resp.hdr.xid = mh->xid;
--
@@ -278,30 +278,25 @@ static struct resp_not_on_link_t {
/**
* dhcpv6_opt() - Get option from DHCPv6 message
- * @p: Packet pool, single packet with UDP header
- * @offset: Offset to look at, 0: end of header, set to option start
+ * @data: Data to look at
* @type: Option type to look up, network order
*
* Return: pointer to option header, or NULL on malformed or missing option
*/
-static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
- uint16_t type)
+static struct opt_hdr *dhcpv6_opt(struct iov_tail *data, uint16_t type)
{
- struct opt_hdr *o;
- size_t left;
+ struct opt_hdr *o, oc;
- ASSERT(*offset >= UDP_MSG_HDR_SIZE);
-
- while ((o = packet_get_try(p, 0, *offset, sizeof(*o), &left))) {
+ while ((o = IOV_PEEK_HEADER(data, oc))) {
unsigned int opt_len = ntohs(o->l) + sizeof(*o);
- if (ntohs(o->l) > left)
+ if (opt_len > iov_tail_size(data))
return NULL;
if (o->t == type)
return o;
- *offset += opt_len;
+ data->off += opt_len;
}
return NULL;
@@ -309,31 +304,31 @@ static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
/**
* dhcpv6_ia_notonlink() - Check if any IA contains non-appropriate addresses
- * @p: Packet pool, single packet starting from UDP header
+ * @data: Data to look at, packet starting from UDP header
* @la: Address we want to lease to the client
*
* Return: pointer to non-appropriate IA_NA or IA_TA, if any, NULL otherwise
*/
-static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
+static struct opt_hdr *dhcpv6_ia_notonlink(const struct iov_tail *data,
struct in6_addr *la)
{
int ia_types[2] = { OPT_IA_NA, OPT_IA_TA }, *ia_type;
const struct opt_ia_addr *opt_addr;
char buf[INET6_ADDRSTRLEN];
struct in6_addr req_addr;
+ struct iov_tail current;
const struct opt_hdr *h;
struct opt_hdr *ia;
- size_t offset;
foreach(ia_type, ia_types) {
- offset = UDP_MSG_HDR_SIZE;
- while ((ia = dhcpv6_opt(p, &offset, *ia_type))) {
+ current = *data;
+ while ((ia = dhcpv6_opt(¤t, *ia_type))) {
if (ntohs(ia->l) < OPT_VSIZE(ia_na))
return NULL;
- offset += sizeof(struct opt_ia_na);
+ current.off += sizeof(struct opt_ia_na);
- while ((h = dhcpv6_opt(p, &offset, OPT_IAAADR))) {
+ while ((h = dhcpv6_opt(¤t, OPT_IAAADR))) {
if (ntohs(h->l) != OPT_VSIZE(ia_addr))
return NULL;
@@ -342,7 +337,7 @@ static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
if (!IN6_ARE_ADDR_EQUAL(la, &req_addr))
goto err;
- offset += sizeof(struct opt_ia_addr);
+ current.off += sizeof(struct opt_ia_addr);
}
}
}
@@ -434,13 +429,15 @@ search:
/**
* dhcpv6_client_fqdn_fill() - Fill in client FQDN option
+ * @data: Data to look at
* @c: Execution context
* @buf: Response message buffer where options will be appended
* @offset: Offset in message buffer for new options
*
* Return: updated length of response message buffer.
*/
-static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
+static size_t dhcpv6_client_fqdn_fill(struct iov_tail *data,
+ const struct ctx *c,
char *buf, int offset)
{
@@ -463,9 +460,8 @@ static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
o = (struct opt_client_fqdn *)(buf + offset);
encode_domain_name(o->domain_name, c->fqdn);
- req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p,
- &(size_t){ UDP_MSG_HDR_SIZE },
- OPT_CLIENT_FQDN);
+ data->off += UDP_MSG_HDR_SIZE;
+ req_opt = (struct opt_client_fqdn *)dhcpv6_opt(data, OPT_CLIENT_FQDN);
if (req_opt && req_opt->flags & 0x01 /* S flag */)
o->flags = 0x02 /* O flag */;
else
@@ -525,19 +521,19 @@ int dhcpv6(struct ctx *c, const struct pool *p,
src = &c->ip6.our_tap_ll;
- mh = IOV_PEEK_HEADER(&data, mhc);
+ mh = IOV_REMOVE_HEADER(&data, mhc);
if (!mh)
return -1;
- client_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_CLIENTID);
+ client_id = dhcpv6_opt(&data, OPT_CLIENTID);
if (!client_id || ntohs(client_id->l) > OPT_VSIZE(client_id))
return -1;
- server_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_SERVERID);
+ server_id = dhcpv6_opt(&data, OPT_SERVERID);
if (server_id && ntohs(server_id->l) != OPT_VSIZE(server_id))
return -1;
- ia = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_NA);
+ ia = dhcpv6_opt(&data, OPT_IA_NA);
if (ia && ntohs(ia->l) < MIN(OPT_VSIZE(ia_na), OPT_VSIZE(ia_ta)))
return -1;
@@ -553,7 +549,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
if (mh->type == TYPE_CONFIRM && server_id)
return -1;
- if ((bad_ia = dhcpv6_ia_notonlink(p, &c->ip6.addr))) {
+ if ((bad_ia = dhcpv6_ia_notonlink(&data, &c->ip6.addr))) {
info("DHCPv6: received CONFIRM with inappropriate IA,"
" sending NotOnLink status in REPLY");
@@ -587,7 +583,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
memcmp(&resp.server_id, server_id, sizeof(resp.server_id)))
return -1;
- if (ia || dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_TA))
+ if (ia || dhcpv6_opt(&data, OPT_IA_TA))
return -1;
info("DHCPv6: received INFORMATION_REQUEST, sending REPLY");
@@ -619,7 +615,8 @@ int dhcpv6(struct ctx *c, const struct pool *p,
n = offsetof(struct resp_t, client_id) +
sizeof(struct opt_hdr) + ntohs(client_id->l);
n = dhcpv6_dns_fill(c, (char *)&resp, n);
- n = dhcpv6_client_fqdn_fill(p, c, (char *)&resp, n);
+ packet_base(p, 0, &data);
+ n = dhcpv6_client_fqdn_fill(&data, c, (char *)&resp, n);
resp.hdr.xid = mh->xid;
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 15/18] dhcp: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (13 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 14/18] dhcpv6: Use iov_tail in dhcpv6_opt() Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-03 5:47 ` David Gibson
2025-04-02 17:23 ` [PATCH 16/18] tap: " Laurent Vivier
` (2 subsequent siblings)
17 siblings, 1 reply; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
and IOV_PEEK_HEADER() rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
dhcp.c | 38 ++++++++++++++++++++++----------------
iov.c | 1 -
2 files changed, 22 insertions(+), 17 deletions(-)
diff --git a/dhcp.c b/dhcp.c
index b0de04be6f27..f3167beb18b7 100644
--- a/dhcp.c
+++ b/dhcp.c
@@ -302,27 +302,32 @@ static void opt_set_dns_search(const struct ctx *c, size_t max_len)
*/
int dhcp(const struct ctx *c, const struct pool *p)
{
- size_t mlen, dlen, offset = 0, opt_len, opt_off = 0;
+ size_t mlen, dlen, opt_len, opt_off = 0;
char macstr[ETH_ADDRSTRLEN];
struct in_addr mask, dst;
const struct ethhdr *eh;
const struct iphdr *iph;
const struct udphdr *uh;
+ struct iov_tail data;
struct msg const *m;
+ struct msg mc;
+ struct ethhdr ehc;
+ struct iphdr iphc;
+ struct udphdr uhc;
struct msg reply;
unsigned int i;
- eh = packet_get(p, 0, offset, sizeof(*eh), NULL);
- offset += sizeof(*eh);
+ if (!packet_base(p, 0, &data))
+ return -1;
- iph = packet_get(p, 0, offset, sizeof(*iph), NULL);
+ eh = IOV_REMOVE_HEADER(&data, ehc);
+ iph = IOV_PEEK_HEADER(&data, iphc);
if (!eh || !iph)
return -1;
- offset += iph->ihl * 4UL;
- uh = packet_get(p, 0, offset, sizeof(*uh), &mlen);
- offset += sizeof(*uh);
+ data.off += iph->ihl * 4UL;
+ uh = IOV_REMOVE_HEADER(&data, uhc);
if (!uh)
return -1;
@@ -332,7 +337,9 @@ int dhcp(const struct ctx *c, const struct pool *p)
if (c->no_dhcp)
return 1;
- m = packet_get(p, 0, offset, offsetof(struct msg, o), &opt_len);
+ mlen = iov_tail_size(&data);
+ m = (struct msg const *)iov_remove_header_(&data, &mc, offsetof(struct msg, o),
+ __alignof__(struct msg));
if (!m ||
mlen != ntohs(uh->len) - sizeof(*uh) ||
mlen < offsetof(struct msg, o) ||
@@ -355,25 +362,24 @@ int dhcp(const struct ctx *c, const struct pool *p)
memset(&reply.file, 0, sizeof(reply.file));
reply.magic = m->magic;
- offset += offsetof(struct msg, o);
-
for (i = 0; i < ARRAY_SIZE(opts); i++)
opts[i].clen = -1;
+ opt_len = iov_tail_size(&data);
while (opt_off + 2 < opt_len) {
- const uint8_t *olen, *val;
+ const uint8_t *olen;
uint8_t *type;
- type = packet_get(p, 0, offset + opt_off, 1, NULL);
- olen = packet_get(p, 0, offset + opt_off + 1, 1, NULL);
+ type = iov_tail_ptr(&data, opt_off, 1);
+ olen = iov_tail_ptr(&data, opt_off + 1, 1);
if (!type || !olen)
return -1;
- val = packet_get(p, 0, offset + opt_off + 2, *olen, NULL);
- if (!val)
+ if (iov_tail_size(&data) < opt_off + 2 + *olen)
return -1;
- memcpy(&opts[*type].c, val, *olen);
+ iov_to_buf(&data.iov[0], data.cnt, data.off + opt_off + 2,
+ &opts[*type].c, *olen);
opts[*type].clen = *olen;
opt_off += *olen + 2;
}
diff --git a/iov.c b/iov.c
index 0c69379316aa..66f15585a61a 100644
--- a/iov.c
+++ b/iov.c
@@ -253,7 +253,6 @@ bool iov_drop(struct iov_tail *tail, size_t len)
* Returns: pointer to the data in the tail, NULL if the
* tail doesn't contains @len bytes.
*/
-/* cppcheck-suppress unusedFunction */
void *iov_tail_ptr(struct iov_tail *tail, size_t off, size_t len)
{
const struct iovec *iov;
--
@@ -253,7 +253,6 @@ bool iov_drop(struct iov_tail *tail, size_t len)
* Returns: pointer to the data in the tail, NULL if the
* tail doesn't contains @len bytes.
*/
-/* cppcheck-suppress unusedFunction */
void *iov_tail_ptr(struct iov_tail *tail, size_t off, size_t len)
{
const struct iovec *iov;
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 16/18] tap: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (14 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 15/18] dhcp: Convert to iov_tail Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-02 17:23 ` [PATCH 17/18] ip: Use iov_tail in ipv6_l4hdr() Laurent Vivier
2025-04-02 17:23 ` [PATCH 18/18] tap: Convert to iov_tail Laurent Vivier
17 siblings, 0 replies; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_PEEK_HEADER()
rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
tap.c | 31 ++++++++++++++++++-------------
1 file changed, 18 insertions(+), 13 deletions(-)
diff --git a/tap.c b/tap.c
index 4b54807c4101..bb4e23df226e 100644
--- a/tap.c
+++ b/tap.c
@@ -680,28 +680,33 @@ static int tap4_handler(struct ctx *c, const struct pool *in,
i = 0;
resume:
for (seq_count = 0, seq = NULL; i < in->count; i++) {
- size_t l2len, l3len, hlen, l4len;
+ size_t l3len, hlen, l4len;
const struct ethhdr *eh;
const struct udphdr *uh;
struct iov_tail data;
+ struct ethhdr ehc;
struct iphdr *iph;
- const char *l4h;
+ struct iphdr iphc;
+ struct udphdr uhc;
- packet_get(in, i, 0, 0, &l2len);
+ if (!packet_base(in, i, &data))
+ continue;
- eh = packet_get(in, i, 0, sizeof(*eh), &l3len);
+ eh = IOV_PEEK_HEADER(&data, ehc);
if (!eh)
continue;
if (ntohs(eh->h_proto) == ETH_P_ARP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
packet_add(pkt, &data);
arp(c, pkt);
continue;
}
- iph = packet_get(in, i, sizeof(*eh), sizeof(*iph), NULL);
+ data.off += sizeof(*eh);
+ l3len = iov_tail_size(&data);
+
+ iph = IOV_PEEK_HEADER(&data, iphc);
if (!iph)
continue;
@@ -729,8 +734,8 @@ resume:
if (iph->saddr && c->ip4.addr_seen.s_addr != iph->saddr)
c->ip4.addr_seen.s_addr = iph->saddr;
- l4h = packet_get(in, i, sizeof(*eh) + hlen, l4len, NULL);
- if (!l4h)
+ data.off += hlen;
+ if (iov_tail_size(&data) != l4len)
continue;
if (iph->protocol == IPPROTO_ICMP) {
@@ -741,7 +746,6 @@ resume:
tap_packet_debug(iph, NULL, NULL, 0, NULL, 1);
- data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
packet_add(pkt, &data);
icmp_tap_handler(c, PIF_TAP, AF_INET,
&iph->saddr, &iph->daddr,
@@ -749,15 +753,17 @@ resume:
continue;
}
- uh = packet_get(in, i, sizeof(*eh) + hlen, sizeof(*uh), NULL);
+ uh = IOV_PEEK_HEADER(&data, uhc);
if (!uh)
continue;
if (iph->protocol == IPPROTO_UDP) {
+ struct iov_tail eh_data;
+
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
- packet_add(pkt, &data);
+ packet_base(in, i, &eh_data);
+ packet_add(pkt, &eh_data);
if (dhcp(c, pkt))
continue;
}
@@ -806,7 +812,6 @@ resume:
#undef L4_SET
append:
- data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
packet_add((struct pool *)&seq->p, &data);
}
--
@@ -680,28 +680,33 @@ static int tap4_handler(struct ctx *c, const struct pool *in,
i = 0;
resume:
for (seq_count = 0, seq = NULL; i < in->count; i++) {
- size_t l2len, l3len, hlen, l4len;
+ size_t l3len, hlen, l4len;
const struct ethhdr *eh;
const struct udphdr *uh;
struct iov_tail data;
+ struct ethhdr ehc;
struct iphdr *iph;
- const char *l4h;
+ struct iphdr iphc;
+ struct udphdr uhc;
- packet_get(in, i, 0, 0, &l2len);
+ if (!packet_base(in, i, &data))
+ continue;
- eh = packet_get(in, i, 0, sizeof(*eh), &l3len);
+ eh = IOV_PEEK_HEADER(&data, ehc);
if (!eh)
continue;
if (ntohs(eh->h_proto) == ETH_P_ARP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
packet_add(pkt, &data);
arp(c, pkt);
continue;
}
- iph = packet_get(in, i, sizeof(*eh), sizeof(*iph), NULL);
+ data.off += sizeof(*eh);
+ l3len = iov_tail_size(&data);
+
+ iph = IOV_PEEK_HEADER(&data, iphc);
if (!iph)
continue;
@@ -729,8 +734,8 @@ resume:
if (iph->saddr && c->ip4.addr_seen.s_addr != iph->saddr)
c->ip4.addr_seen.s_addr = iph->saddr;
- l4h = packet_get(in, i, sizeof(*eh) + hlen, l4len, NULL);
- if (!l4h)
+ data.off += hlen;
+ if (iov_tail_size(&data) != l4len)
continue;
if (iph->protocol == IPPROTO_ICMP) {
@@ -741,7 +746,6 @@ resume:
tap_packet_debug(iph, NULL, NULL, 0, NULL, 1);
- data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
packet_add(pkt, &data);
icmp_tap_handler(c, PIF_TAP, AF_INET,
&iph->saddr, &iph->daddr,
@@ -749,15 +753,17 @@ resume:
continue;
}
- uh = packet_get(in, i, sizeof(*eh) + hlen, sizeof(*uh), NULL);
+ uh = IOV_PEEK_HEADER(&data, uhc);
if (!uh)
continue;
if (iph->protocol == IPPROTO_UDP) {
+ struct iov_tail eh_data;
+
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
- packet_add(pkt, &data);
+ packet_base(in, i, &eh_data);
+ packet_add(pkt, &eh_data);
if (dhcp(c, pkt))
continue;
}
@@ -806,7 +812,6 @@ resume:
#undef L4_SET
append:
- data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
packet_add((struct pool *)&seq->p, &data);
}
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 17/18] ip: Use iov_tail in ipv6_l4hdr()
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (15 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 16/18] tap: " Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
2025-04-02 17:23 ` [PATCH 18/18] tap: Convert to iov_tail Laurent Vivier
17 siblings, 0 replies; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
and IOV_PEEK_HEADER() rather than packet_get().
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
ip.c | 27 ++++++++++++---------------
ip.h | 3 +--
tap.c | 4 +++-
3 files changed, 16 insertions(+), 18 deletions(-)
diff --git a/ip.c b/ip.c
index 2cc7f6548aff..f13aae08f918 100644
--- a/ip.c
+++ b/ip.c
@@ -23,40 +23,37 @@
/**
* ipv6_l4hdr() - Find pointer to L4 header in IPv6 packet and extract protocol
- * @p: Packet pool, packet number @idx has IPv6 header at @offset
- * @idx: Index of packet in pool
- * @offset: Pre-calculated IPv6 header offset
+ * @data: IPv6 packet
* @proto: Filled with L4 protocol number
* @dlen: Data length (payload excluding header extensions), set on return
*
* Return: pointer to L4 header, NULL if not found
*/
-char *ipv6_l4hdr(const struct pool *p, int idx, size_t offset, uint8_t *proto,
- size_t *dlen)
+bool ipv6_l4hdr(struct iov_tail *data, uint8_t *proto, size_t *dlen)
{
const struct ipv6_opt_hdr *o;
+ struct ipv6_opt_hdr oc;
const struct ipv6hdr *ip6h;
- char *base;
+ struct ipv6hdr ip6hc;
int hdrlen;
uint8_t nh;
- base = packet_get(p, idx, 0, 0, NULL);
- ip6h = packet_get(p, idx, offset, sizeof(*ip6h), dlen);
+ ip6h = IOV_REMOVE_HEADER(data, ip6hc);
if (!ip6h)
- return NULL;
-
- offset += sizeof(*ip6h);
+ return false;
+ *dlen = iov_tail_size(data);
nh = ip6h->nexthdr;
if (!IPV6_NH_OPT(nh))
goto found;
- while ((o = packet_get_try(p, idx, offset, sizeof(*o), dlen))) {
+ while ((o = IOV_PEEK_HEADER(data, oc))) {
+ *dlen = iov_tail_size(data) - sizeof(*o);
nh = o->nexthdr;
hdrlen = (o->hdrlen + 1) * 8;
if (IPV6_NH_OPT(nh))
- offset += hdrlen;
+ data->off += hdrlen;
else
goto found;
}
@@ -65,8 +62,8 @@ char *ipv6_l4hdr(const struct pool *p, int idx, size_t offset, uint8_t *proto,
found:
if (nh == 59)
- return NULL;
+ return false;
*proto = nh;
- return base + offset;
+ return true;
}
diff --git a/ip.h b/ip.h
index 471c57ee4c71..874cbe476a6b 100644
--- a/ip.h
+++ b/ip.h
@@ -115,8 +115,7 @@ static inline uint32_t ip6_get_flow_lbl(const struct ipv6hdr *ip6h)
ip6h->flow_lbl[2];
}
-char *ipv6_l4hdr(const struct pool *p, int idx, size_t offset, uint8_t *proto,
- size_t *dlen);
+bool ipv6_l4hdr(struct iov_tail *data, uint8_t *proto, size_t *dlen);
/* IPv6 link-local all-nodes multicast adddress, ff02::1 */
static const struct in6_addr in6addr_ll_all_nodes = {
diff --git a/tap.c b/tap.c
index bb4e23df226e..280a04981954 100644
--- a/tap.c
+++ b/tap.c
@@ -888,8 +888,10 @@ resume:
if (plen != check)
continue;
- if (!(l4h = ipv6_l4hdr(in, i, sizeof(*eh), &proto, &l4len)))
+ data = IOV_TAIL_FROM_BUF(ip6h, sizeof(*ip6h) + check, 0);
+ if (!ipv6_l4hdr(&data, &proto, &l4len))
continue;
+ l4h = (char *)data.iov[0].iov_base + data.off;
if (IN6_IS_ADDR_LOOPBACK(saddr) || IN6_IS_ADDR_LOOPBACK(daddr)) {
char sstr[INET6_ADDRSTRLEN], dstr[INET6_ADDRSTRLEN];
--
@@ -888,8 +888,10 @@ resume:
if (plen != check)
continue;
- if (!(l4h = ipv6_l4hdr(in, i, sizeof(*eh), &proto, &l4len)))
+ data = IOV_TAIL_FROM_BUF(ip6h, sizeof(*ip6h) + check, 0);
+ if (!ipv6_l4hdr(&data, &proto, &l4len))
continue;
+ l4h = (char *)data.iov[0].iov_base + data.off;
if (IN6_IS_ADDR_LOOPBACK(saddr) || IN6_IS_ADDR_LOOPBACK(daddr)) {
char sstr[INET6_ADDRSTRLEN], dstr[INET6_ADDRSTRLEN];
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* [PATCH 18/18] tap: Convert to iov_tail
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
` (16 preceding siblings ...)
2025-04-02 17:23 ` [PATCH 17/18] ip: Use iov_tail in ipv6_l4hdr() Laurent Vivier
@ 2025-04-02 17:23 ` Laurent Vivier
17 siblings, 0 replies; 34+ messages in thread
From: Laurent Vivier @ 2025-04-02 17:23 UTC (permalink / raw)
To: passt-dev; +Cc: Laurent Vivier
Use packet_base() and extract headers using IOV_REMOVE_HEADER()
and IOV_PEEK_HEADER() rather than packet_get().
Remove packet_get() as it is not used anymore.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
packet.c | 53 -----------------------------------------------------
packet.h | 10 ----------
tap.c | 23 ++++++++++++++---------
3 files changed, 14 insertions(+), 72 deletions(-)
diff --git a/packet.c b/packet.c
index 8066ac12502b..e917b0daad2a 100644
--- a/packet.c
+++ b/packet.c
@@ -103,59 +103,6 @@ void packet_add_do(struct pool *p, struct iov_tail *data,
p->count++;
}
-/**
- * packet_get_do() - Get data range from packet descriptor from given pool
- * @p: Packet pool
- * @idx: Index of packet descriptor in pool
- * @offset: Offset of data range in packet descriptor
- * @len: Length of desired data range
- * @left: Length of available data after range, set on return, can be NULL
- * @func: For tracing: name of calling function, NULL means no trace()
- * @line: For tracing: caller line of function call
- *
- * Return: pointer to start of data range, NULL on invalid range or descriptor
- */
-void *packet_get_do(const struct pool *p, size_t idx, size_t offset,
- size_t len, size_t *left, const char *func, int line)
-{
- char *ptr;
-
- if (idx >= p->size || idx >= p->count) {
- if (func) {
- trace("packet %zu from pool size: %zu, count: %zu, "
- "%s:%i", idx, p->size, p->count, func, line);
- }
- return NULL;
- }
-
- if (len > PACKET_MAX_LEN) {
- if (func) {
- trace("packet data length %zu, %s:%i",
- len, func, line);
- }
- return NULL;
- }
-
- if (len + offset > p->pkt[idx].iov_len) {
- if (func) {
- trace("data length %zu, offset %zu from length %zu, "
- "%s:%i", len, offset, p->pkt[idx].iov_len,
- func, line);
- }
- return NULL;
- }
-
- ptr = (char *)p->pkt[idx].iov_base + offset;
-
- if (packet_check_range(p, ptr, len, func, line))
- return NULL;
-
- if (left)
- *left = p->pkt[idx].iov_len - offset - len;
-
- return ptr;
-}
-
/**
* packet_base_do() - Get data range from packet descriptor from given pool
* @p: Packet pool
diff --git a/packet.h b/packet.h
index 35058e747a43..787535a228a5 100644
--- a/packet.h
+++ b/packet.h
@@ -32,9 +32,6 @@ struct pool {
int vu_packet_check_range(void *buf, const char *ptr, size_t len);
void packet_add_do(struct pool *p, struct iov_tail *data,
const char *func, int line);
-void *packet_get_do(const struct pool *p, const size_t idx,
- size_t offset, size_t len, size_t *left,
- const char *func, int line);
bool packet_base_do(const struct pool *p, const size_t idx,
struct iov_tail *data,
const char *func, int line);
@@ -43,13 +40,6 @@ void pool_flush(struct pool *p);
#define packet_add(p, data) \
packet_add_do(p, data, __func__, __LINE__)
-#define packet_get(p, idx, offset, len, left) \
- packet_get_do(p, idx, offset, len, left, __func__, __LINE__)
-
-
-#define packet_get_try(p, idx, offset, len, left) \
- packet_get_do(p, idx, offset, len, left, NULL, 0)
-
#define packet_base(p, idx, data) \
packet_base_do(p, idx, data, __func__, __LINE__)
diff --git a/tap.c b/tap.c
index 280a04981954..d6a1da8481a2 100644
--- a/tap.c
+++ b/tap.c
@@ -870,17 +870,24 @@ resume:
const struct udphdr *uh;
struct iov_tail data;
struct ipv6hdr *ip6h;
+ struct ipv6hdr ip6hc;
+ struct ethhdr ehc;
+ struct udphdr uhc;
uint8_t proto;
- char *l4h;
- eh = packet_get(in, i, 0, sizeof(*eh), NULL);
+ if (!packet_base(in, i, &data))
+ return -1;
+
+ eh = IOV_REMOVE_HEADER(&data, ehc);
if (!eh)
continue;
- ip6h = packet_get(in, i, sizeof(*eh), sizeof(*ip6h), &check);
+ ip6h = IOV_PEEK_HEADER(&data, ip6hc);
if (!ip6h)
continue;
+ check = iov_tail_size(&data) - sizeof(*ip6h);
+
saddr = &ip6h->saddr;
daddr = &ip6h->daddr;
@@ -888,10 +895,8 @@ resume:
if (plen != check)
continue;
- data = IOV_TAIL_FROM_BUF(ip6h, sizeof(*ip6h) + check, 0);
if (!ipv6_l4hdr(&data, &proto, &l4len))
continue;
- l4h = (char *)data.iov[0].iov_base + data.off;
if (IN6_IS_ADDR_LOOPBACK(saddr) || IN6_IS_ADDR_LOOPBACK(daddr)) {
char sstr[INET6_ADDRSTRLEN], dstr[INET6_ADDRSTRLEN];
@@ -916,6 +921,8 @@ resume:
}
if (proto == IPPROTO_ICMPV6) {
+ const struct icmp6hdr *l4h;
+ struct icmp6hdr l4hc;
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
if (c->no_icmp)
@@ -924,9 +931,9 @@ resume:
if (l4len < sizeof(struct icmp6hdr))
continue;
- data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
packet_add(pkt, &data);
+ l4h = IOV_PEEK_HEADER(&data, l4hc);
if (ndp(c, (struct icmp6hdr *)l4h, saddr, pkt))
continue;
@@ -939,12 +946,11 @@ resume:
if (l4len < sizeof(*uh))
continue;
- uh = (struct udphdr *)l4h;
+ uh = IOV_PEEK_HEADER(&data, uhc);
if (proto == IPPROTO_UDP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
packet_add(pkt, &data);
if (dhcpv6(c, pkt, saddr, daddr))
@@ -999,7 +1005,6 @@ resume:
#undef L4_SET
append:
- data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
packet_add((struct pool *)&seq->p, &data);
}
--
@@ -870,17 +870,24 @@ resume:
const struct udphdr *uh;
struct iov_tail data;
struct ipv6hdr *ip6h;
+ struct ipv6hdr ip6hc;
+ struct ethhdr ehc;
+ struct udphdr uhc;
uint8_t proto;
- char *l4h;
- eh = packet_get(in, i, 0, sizeof(*eh), NULL);
+ if (!packet_base(in, i, &data))
+ return -1;
+
+ eh = IOV_REMOVE_HEADER(&data, ehc);
if (!eh)
continue;
- ip6h = packet_get(in, i, sizeof(*eh), sizeof(*ip6h), &check);
+ ip6h = IOV_PEEK_HEADER(&data, ip6hc);
if (!ip6h)
continue;
+ check = iov_tail_size(&data) - sizeof(*ip6h);
+
saddr = &ip6h->saddr;
daddr = &ip6h->daddr;
@@ -888,10 +895,8 @@ resume:
if (plen != check)
continue;
- data = IOV_TAIL_FROM_BUF(ip6h, sizeof(*ip6h) + check, 0);
if (!ipv6_l4hdr(&data, &proto, &l4len))
continue;
- l4h = (char *)data.iov[0].iov_base + data.off;
if (IN6_IS_ADDR_LOOPBACK(saddr) || IN6_IS_ADDR_LOOPBACK(daddr)) {
char sstr[INET6_ADDRSTRLEN], dstr[INET6_ADDRSTRLEN];
@@ -916,6 +921,8 @@ resume:
}
if (proto == IPPROTO_ICMPV6) {
+ const struct icmp6hdr *l4h;
+ struct icmp6hdr l4hc;
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
if (c->no_icmp)
@@ -924,9 +931,9 @@ resume:
if (l4len < sizeof(struct icmp6hdr))
continue;
- data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
packet_add(pkt, &data);
+ l4h = IOV_PEEK_HEADER(&data, l4hc);
if (ndp(c, (struct icmp6hdr *)l4h, saddr, pkt))
continue;
@@ -939,12 +946,11 @@ resume:
if (l4len < sizeof(*uh))
continue;
- uh = (struct udphdr *)l4h;
+ uh = IOV_PEEK_HEADER(&data, uhc);
if (proto == IPPROTO_UDP) {
PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
- data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
packet_add(pkt, &data);
if (dhcpv6(c, pkt, saddr, daddr))
@@ -999,7 +1005,6 @@ resume:
#undef L4_SET
append:
- data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
packet_add((struct pool *)&seq->p, &data);
}
--
2.49.0
^ permalink raw reply related [flat|nested] 34+ messages in thread
* Re: [PATCH 01/18] arp: Don't mix incoming and outgoing buffers
2025-04-02 17:23 ` [PATCH 01/18] arp: Don't mix incoming and outgoing buffers Laurent Vivier
@ 2025-04-03 1:57 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 1:57 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 4616 bytes --]
On Wed, Apr 02, 2025 at 07:23:26PM +0200, Laurent Vivier wrote:
> Don't use the memory of the incoming packet to build the outgoing buffer
> as it can be memory of the TX queue in the case of vhost-user.
>
> Moreover with vhost-user, the packet can be splitted accross several
> iovec and it's easier to rebuild it in a buffer than updating an
> existing iovec array.
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> arp.c | 84 ++++++++++++++++++++++++++++++++++++++---------------------
> 1 file changed, 55 insertions(+), 29 deletions(-)
>
> diff --git a/arp.c b/arp.c
> index fc482bbd9938..9d68d7c3b602 100644
> --- a/arp.c
> +++ b/arp.c
> @@ -31,56 +31,82 @@
> #include "tap.h"
>
> /**
> - * arp() - Check if this is a supported ARP message, reply as needed
> + * ignore_arp() - Check if this is a supported ARP message
> * @c: Execution context
> - * @p: Packet pool, single packet with Ethernet buffer
> + * @ah: ARP header
> + * @am: ARP message
> *
> - * Return: 1 if handled, -1 on failure
> + * Return: true if the message is supported, false otherwise.
> */
> -int arp(const struct ctx *c, const struct pool *p)
> +static bool ignore_arp(const struct ctx *c,
> + const struct arphdr *ah, const struct arpmsg *am)
> {
> - unsigned char swap[4];
> - struct ethhdr *eh;
> - struct arphdr *ah;
> - struct arpmsg *am;
> - size_t l2len;
> -
> - eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
> - ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
> - am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
> -
> - if (!eh || !ah || !am)
> - return -1;
> -
> if (ah->ar_hrd != htons(ARPHRD_ETHER) ||
> ah->ar_pro != htons(ETH_P_IP) ||
> ah->ar_hln != ETH_ALEN ||
> ah->ar_pln != 4 ||
> ah->ar_op != htons(ARPOP_REQUEST))
> - return 1;
> + return true;
>
> /* Discard announcements, but not 0.0.0.0 "probes" */
> if (memcmp(am->sip, &in4addr_any, sizeof(am->sip)) &&
> !memcmp(am->sip, am->tip, sizeof(am->sip)))
> - return 1;
> + return true;
>
> /* Don't resolve the guest's assigned address, either. */
> if (!memcmp(am->tip, &c->ip4.addr, sizeof(am->tip)))
> + return true;
> +
> + return false;
> +}
> +
> +/**
> + * arp() - Check if this is a supported ARP message, reply as needed
> + * @c: Execution context
> + * @p: Packet pool, single packet with Ethernet buffer
> + *
> + * Return: 1 if handled, -1 on failure
> + */
> +int arp(const struct ctx *c, const struct pool *p)
> +{
> + struct {
> + struct ethhdr eh;
> + struct arphdr ah;
> + struct arpmsg am;
> + } __attribute__((__packed__)) resp;
> + const struct ethhdr *eh;
> + const struct arphdr *ah;
> + const struct arpmsg *am;
> +
> + eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
> + ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
> + am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
> +
> + if (!eh || !ah || !am)
> + return -1;
> +
> + if (ignore_arp(c, ah, am))
> return 1;
>
> - ah->ar_op = htons(ARPOP_REPLY);
> - memcpy(am->tha, am->sha, sizeof(am->tha));
> - memcpy(am->sha, c->our_tap_mac, sizeof(am->sha));
> + /* ethernet header */
> + resp.eh.h_proto = htons(ETH_P_ARP);
> + memcpy(resp.eh.h_dest, eh->h_source, sizeof(resp.eh.h_dest));
> + memcpy(resp.eh.h_source, c->our_tap_mac, sizeof(resp.eh.h_source));
>
> - memcpy(swap, am->tip, sizeof(am->tip));
> - memcpy(am->tip, am->sip, sizeof(am->tip));
> - memcpy(am->sip, swap, sizeof(am->sip));
> + /* ARP header */
> + resp.ah.ar_op = htons(ARPOP_REPLY);
> + resp.ah.ar_hrd = ah->ar_hrd;
> + resp.ah.ar_pro = ah->ar_pro;
> + resp.ah.ar_hln = ah->ar_hln;
> + resp.ah.ar_pln = ah->ar_pln;
>
> - l2len = sizeof(*eh) + sizeof(*ah) + sizeof(*am);
> - memcpy(eh->h_dest, eh->h_source, sizeof(eh->h_dest));
> - memcpy(eh->h_source, c->our_tap_mac, sizeof(eh->h_source));
> + /* ARP message */
> + memcpy(resp.am.sha, c->our_tap_mac, sizeof(resp.am.sha));
> + memcpy(resp.am.sip, am->tip, sizeof(resp.am.sip));
> + memcpy(resp.am.tha, am->sha, sizeof(resp.am.tha));
> + memcpy(resp.am.tip, am->sip, sizeof(resp.am.tip));
>
> - tap_send_single(c, eh, l2len);
> + tap_send_single(c, &resp, sizeof(resp));
>
> return 1;
> }
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 02/18] iov: Update IOV_REMOVE_HEADER() and IOV_PEEK_HEADER()
2025-04-02 17:23 ` [PATCH 02/18] iov: Update IOV_REMOVE_HEADER() and IOV_PEEK_HEADER() Laurent Vivier
@ 2025-04-03 2:36 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 2:36 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 13921 bytes --]
On Wed, Apr 02, 2025 at 07:23:27PM +0200, Laurent Vivier wrote:
> Provide a temporary variable of the wanted type to store
> the header if the memory in the iovec array is not contiguous.
>
> Also introduce iov_tail_ptr(), iov_drop() and iov_copy()
> for later use.
Not sure if these belong in the same patch.
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> iov.c | 133 ++++++++++++++++++++++++++++++++++++++++++++++++++----
> iov.h | 53 ++++++++++++++++------
> tcp_buf.c | 2 +-
> 3 files changed, 163 insertions(+), 25 deletions(-)
>
> diff --git a/iov.c b/iov.c
> index 8c63b7ea6e31..d96fc2ab594b 100644
> --- a/iov.c
> +++ b/iov.c
> @@ -108,7 +108,7 @@ size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt,
> *
> * Returns: The number of bytes successfully copied.
> */
> -/* cppcheck-suppress unusedFunction */
> +/* cppcheck-suppress [staticFunction,unmatchedSuppression] */
> size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
> size_t offset, void *buf, size_t bytes)
> {
> @@ -126,6 +126,7 @@ size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
> /* copying data */
> for (copied = 0; copied < bytes && i < iov_cnt; i++) {
> size_t len = MIN(iov[i].iov_len - offset, bytes - copied);
> + /* NOLINTNEXTLINE(clang-analyzer-core.NonNullParamChecker) */
> memcpy((char *)buf + copied, (char *)iov[i].iov_base + offset,
> len);
> copied += len;
> @@ -156,6 +157,45 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt)
> return len;
> }
>
> +/**
> + * iov_copy - Copy data from one scatter/gather I/O vector (struct iovec) to
> + * another.
I think this function name is slightly misleading and the description
is very misleading. What the function does is make a new iov
referencing a subset of the data in the original iov. It doesn't copy
the reference data - the dst iov will alias (some of) the same memory
as the src iov.
I'd suggest iov_slice() maybe?
> + * @dst_iov: Pointer to the destination array of struct iovec describing
> + * the scatter/gather I/O vector to copy to.
> + * @dst_iov_cnt: Number of elements in the destination iov array.
Maybe worth emphasising that this is a maximum, we might not use all of them.
> + * @iov: Pointer to the source array of struct iovec describing
> + * the scatter/gather I/O vector to copy from.
> + * @iov_cnt: Number of elements in the source iov array.
> + * @offset: Offset within the source iov from where copying should start.
> + * @bytes: Total number of bytes to copy from iov to dst_iov.
> + *
> + * Returns: The number of elements successfully copied to the destination
> + * iov array.
So, this is obviously useful, because it's effectively the "after"
value of dst_iov. However, it doesn't necessarily distinguish the
(AFAICT) three exit conditions:
1) "success"; iov_size(dst_iov) == bytes afterwards
2) iov_size(dst_iov) < bytes, because we ran out of data in the
source iov
3) iov_size(dst_iov) < bytes, because we needed more than
@dst_iov_cnt "slots" to reference that much of @iov.
On "failure", whether it's (2) or (3) seems like it could matter, so
it would be nice if we can deduce that from the return value.
> + */
> +/* cppcheck-suppress unusedFunction */
> +unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
> + const struct iovec *iov, size_t iov_cnt,
> + size_t offset, size_t bytes)
> +{
> + unsigned int i, j;
> +
> + i = iov_skip_bytes(iov, iov_cnt, offset, &offset);
> +
> + /* copying data */
> + for (j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) {
> + size_t len = MIN(bytes, iov[i].iov_len - offset);
> +
> + dst_iov[j].iov_base = (char *)iov[i].iov_base + offset;
> + dst_iov[j].iov_len = len;
> + j++;
> + bytes -= len;
> + offset = 0;
> + }
> +
> + return j;
> +}
> +
> /**
> * iov_tail_prune() - Remove any unneeded buffers from an IOV tail
> * @tail: IO vector tail (modified)
> @@ -192,7 +232,50 @@ size_t iov_tail_size(struct iov_tail *tail)
> }
>
> /**
> - * iov_peek_header_() - Get pointer to a header from an IOV tail
> + * iov_drop() - update head of the tail
Cute phrasing, but kind of confusing. I think this wants similar
phrasing to remove_header, since it's doing basically the same thing,
but discarding rather than retreiving the data.
> + * @tail: IO vector tail
> + * @len: length to move the head of the tail
> + *
> + * Returns: true if the tail still contains any bytes, otherwise false
> + */
> +/* cppcheck-suppress unusedFunction */
> +bool iov_drop(struct iov_tail *tail, size_t len)
> +{
> + tail->off = tail->off + len;
> +
> + return iov_tail_prune(tail);
> +}
> +
> +/**
> + * iov_tail_ptr() - get a pointer to the head of the tail
> + * @tail: IO vector tail
> + * @off: Byte offset in the tail to skip
> + * @len: Length of the data to get, in bytes
> + *
> + * Returns: pointer to the data in the tail, NULL if the
> + * tail doesn't contains @len bytes.
This is a dangerous interface, because it returns a pointer with no
indication of how many bytes after it are actually valid. I can see
it being useful internally, but I don't think it should be exported.
> + */
> +/* cppcheck-suppress unusedFunction */
> +void *iov_tail_ptr(struct iov_tail *tail, size_t off, size_t len)
> +{
> + const struct iovec *iov;
> + size_t cnt, i;
> +
> + i = iov_skip_bytes(tail->iov, tail->cnt, tail->off + off, &off);
> + if (i == tail->cnt)
> + return NULL;
> +
> + iov = &tail->iov[i];
> + cnt = tail->cnt - i;
> +
> + if (iov_size(iov, cnt) < off + len)
> + return NULL;
> +
> + return (char *)iov[0].iov_base + off;
> +}
> +
> +/**
> + * iov_check_header - Check if a header can be accessed
> * @tail: IOV tail to get header from
> * @len: Length of header to get, in bytes
> * @align: Required alignment of header, in bytes
> @@ -203,8 +286,7 @@ size_t iov_tail_size(struct iov_tail *tail)
> * overruns the IO vector, is not contiguous or doesn't have the
> * requested alignment.
> */
> -/* cppcheck-suppress [staticFunction,unmatchedSuppression] */
> -void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align)
> +static void *iov_check_header(struct iov_tail *tail, size_t len, size_t align)
> {
> char *p;
>
> @@ -225,7 +307,36 @@ void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align)
> }
>
> /**
> - * iov_remove_header_() - Remove a header from an IOV tail
> + * iov_peek_header_ - Get pointer to a header from an IOV tail
> + * @tail: IOV tail to get header from
Needs a description for @v.
> + * @len: Length of header to get, in bytes
> + * @align: Required alignment of header, in bytes
> + *
> + * @tail may be pruned, but will represent the same bytes as before.
> + *
> + * Returns: Pointer to the first @len logical bytes of the tail, or to
> + * a copy if that overruns the IO vector, is not contiguous or
> + * doesn't have the requested alignment. NULL if that overruns the
> + * IO vector.
> + */
> +/* cppcheck-suppress [staticFunction,unmatchedSuppression] */
> +void *iov_peek_header_(struct iov_tail *tail, void *v, size_t len, size_t align)
> +{
> + char *p = iov_check_header(tail, len, align);
> + size_t l;
> +
> + if (p)
> + return p;
> +
> + l = iov_to_buf(tail->iov, tail->cnt, tail->off, v, len);
> + if (l != len)
> + return NULL;
> +
> + return v;
> +}
> +
> +/**
> + * iov_remove_header_ - Remove a header from an IOV tail
> * @tail: IOV tail to remove header from (modified)
Needs description of @v.
> * @len: Length of header to remove, in bytes
> * @align: Required alignment of header, in bytes
> @@ -233,17 +344,19 @@ void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align)
> * On success, @tail is updated so that it longer includes the bytes of the
> * returned header.
> *
> - * Returns: Pointer to the first @len logical bytes of the tail, NULL if that
> - * overruns the IO vector, is not contiguous or doesn't have the
> - * requested alignment.
> + * Returns: Pointer to the first @len logical bytes of the tail, or to
> + * a copy if that overruns the IO vector, is not contiguous or
> + * doesn't have the requested alignment. NULL if that overruns the
> + * IO vector.
> */
> -void *iov_remove_header_(struct iov_tail *tail, size_t len, size_t align)
> +void *iov_remove_header_(struct iov_tail *tail, void *v, size_t len, size_t align)
> {
> - char *p = iov_peek_header_(tail, len, align);
> + char *p = iov_peek_header_(tail, v, len, align);
>
> if (!p)
> return NULL;
>
> tail->off = tail->off + len;
> +
> return p;
> }
> diff --git a/iov.h b/iov.h
> index 9855bf0c0c32..f9b5fdf0803e 100644
> --- a/iov.h
> +++ b/iov.h
> @@ -28,6 +28,9 @@ size_t iov_from_buf(const struct iovec *iov, size_t iov_cnt,
> size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
> size_t offset, void *buf, size_t bytes);
> size_t iov_size(const struct iovec *iov, size_t iov_cnt);
> +unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
> + const struct iovec *iov, size_t iov_cnt,
> + size_t offset, size_t bytes);
>
> /*
> * DOC: Theory of Operation, struct iov_tail
> @@ -70,38 +73,60 @@ struct iov_tail {
> #define IOV_TAIL(iov_, cnt_, off_) \
> (struct iov_tail){ .iov = (iov_), .cnt = (cnt_), .off = (off_) }
>
> +/**
> + * IOV_TAIL_FROM_BUF() - Create a new IOV tail from a buffer
> + * @buf_: Buffer address to use in the iovec
> + * @len_: Buffer size
> + * @off_: Byte offset in the buffer where the tail begins
> + */
> +#define IOV_TAIL_FROM_BUF(buf_, len_, off_) \
> + IOV_TAIL((&(const struct iovec){ .iov_base = (buf_), .iov_len = (len_) }), 1, (off_))
> +
> bool iov_tail_prune(struct iov_tail *tail);
> size_t iov_tail_size(struct iov_tail *tail);
> -void *iov_peek_header_(struct iov_tail *tail, size_t len, size_t align);
> -void *iov_remove_header_(struct iov_tail *tail, size_t len, size_t align);
> +bool iov_drop(struct iov_tail *tail, size_t len);
> +void *iov_peek_header_(struct iov_tail *tail, void *v, size_t len, size_t align);
> +void *iov_remove_header_(struct iov_tail *tail, void *v, size_t len, size_t align);
> +void *iov_tail_ptr(struct iov_tail *tail, size_t off, size_t len);
>
> /**
> * IOV_PEEK_HEADER() - Get typed pointer to a header from an IOV tail
> * @tail_: IOV tail to get header from
> - * @type_: Data type of the header
> + * @var_: Temporary buffer of the type of the header to use if
> + * the memory in the iovec array is not contiguous.
> *
> * @tail_ may be pruned, but will represent the same bytes as before.
> *
> - * Returns: Pointer of type (@type_ *) located at the start of @tail_, NULL if
> - * we can't get a contiguous and aligned pointer.
> + * Returns: Pointer of type (@type_ *) located at the start of @tail_
This is no longer quite accurate: the data is the same, but it's not
necessarily a pointer into @tail_ proper. There's also still a NULL
return case, just more limited than it was before.
> */
> -#define IOV_PEEK_HEADER(tail_, type_) \
> - ((type_ *)(iov_peek_header_((tail_), \
> - sizeof(type_), __alignof__(type_))))
> +
> +#define IOV_PEEK_HEADER(tail_, var_) \
> + ((__typeof__(var_) *)(iov_peek_header_((tail_), &(var_), \
> + sizeof(var_), __alignof__(var_))))
>
> /**
> * IOV_REMOVE_HEADER() - Remove and return typed header from an IOV tail
> * @tail_: IOV tail to remove header from (modified)
> - * @type_: Data type of the header to remove
> + * @var_: Temporary buffer of the type of the header to use if
> + * the memory in the iovec array is not contiguous.
> *
> * On success, @tail_ is updated so that it longer includes the bytes of the
> * returned header.
> *
> - * Returns: Pointer of type (@type_ *) located at the old start of @tail_, NULL
> - * if we can't get a contiguous and aligned pointer.
> + * Returns: Pointer of type (@type_ *) located at the old start of @tail_
> + */
> +
> +#define IOV_REMOVE_HEADER(tail_, var_) \
> + ((__typeof__(var_) *)(iov_remove_header_((tail_), &(var_), \
> + sizeof(var_), __alignof__(var_))))
> +
> +/** IOV_DROP_HEADER() -- Remove a typed header from an IOV tail
> + * @tail_: IOV tail to remove header from (modified)
> + * @type_: Data type of the header to remove
> + *
> + * Returns: true if the tail still contains any bytes, otherwise false
> */
> -#define IOV_REMOVE_HEADER(tail_, type_) \
> - ((type_ *)(iov_remove_header_((tail_), \
> - sizeof(type_), __alignof__(type_))))
> +#define IOV_DROP_HEADER(tail_, type_) \
> + iov_drop((tail_), sizeof(type_))
>
> #endif /* IOVEC_H */
> diff --git a/tcp_buf.c b/tcp_buf.c
> index 05305636b503..4bcc1acb245a 100644
> --- a/tcp_buf.c
> +++ b/tcp_buf.c
> @@ -160,7 +160,7 @@ static void tcp_l2_buf_fill_headers(const struct tcp_tap_conn *conn,
> uint32_t seq, bool no_tcp_csum)
> {
> struct iov_tail tail = IOV_TAIL(&iov[TCP_IOV_PAYLOAD], 1, 0);
> - struct tcphdr *th = IOV_REMOVE_HEADER(&tail, struct tcphdr);
> + struct tcphdr thc, *th = IOV_REMOVE_HEADER(&tail, thc);
> struct tap_hdr *taph = iov[TCP_IOV_TAP].iov_base;
> const struct flowside *tapside = TAPFLOW(conn);
> const struct in_addr *a4 = inany_v4(&tapside->oaddr);
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 03/18] tap: Use iov_tail with tap_add_packet()
2025-04-02 17:23 ` [PATCH 03/18] tap: Use iov_tail with tap_add_packet() Laurent Vivier
@ 2025-04-03 4:50 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 4:50 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 7011 bytes --]
On Wed, Apr 02, 2025 at 07:23:28PM +0200, Laurent Vivier wrote:
> Use IOV_PEEK_HEADER() to get the ethernet header from the iovec.
>
> Move the workaround about multiple iovec array from vu_handle_tx() to
> tap_add_packet(). Removing the offset out of the iovec array should
> reduce the iovec count to 1.
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> iov.c | 1 -
> pcap.c | 1 +
> tap.c | 30 +++++++++++++++++++++---------
> tap.h | 2 +-
> vu_common.c | 25 +++++--------------------
> 5 files changed, 28 insertions(+), 31 deletions(-)
>
> diff --git a/iov.c b/iov.c
> index d96fc2ab594b..508fb6da91fb 100644
> --- a/iov.c
> +++ b/iov.c
> @@ -238,7 +238,6 @@ size_t iov_tail_size(struct iov_tail *tail)
> *
> * Returns: true if the tail still contains any bytes, otherwise false
> */
> -/* cppcheck-suppress unusedFunction */
> bool iov_drop(struct iov_tail *tail, size_t len)
> {
> tail->off = tail->off + len;
> diff --git a/pcap.c b/pcap.c
> index e95aa6fe29a6..404043a27e22 100644
> --- a/pcap.c
> +++ b/pcap.c
> @@ -76,6 +76,7 @@ static void pcap_frame(const struct iovec *iov, size_t iovcnt,
> * @pkt: Pointer to data buffer, including L2 headers
> * @l2len: L2 frame length
> */
> +/* cppcheck-suppress unusedFunction */
> void pcap(const char *pkt, size_t l2len)
> {
> struct iovec iov = { (char *)pkt, l2len };
> diff --git a/tap.c b/tap.c
> index 182a1151f139..ab3effe80f89 100644
> --- a/tap.c
> +++ b/tap.c
> @@ -1040,29 +1040,36 @@ void tap_handler(struct ctx *c, const struct timespec *now)
> /**
> * tap_add_packet() - Queue/capture packet, update notion of guest MAC address
> * @c: Execution context
> - * @l2len: Total L2 packet length
> - * @p: Packet buffer
> + * @data: Packet to add to the pool
> */
> -void tap_add_packet(struct ctx *c, ssize_t l2len, char *p)
> +void tap_add_packet(struct ctx *c, struct iov_tail *data)
> {
> const struct ethhdr *eh;
> + struct ethhdr ehc;
>
> - pcap(p, l2len);
> + pcap_iov(data->iov, data->cnt, data->off);
>
> - eh = (struct ethhdr *)p;
> + eh = IOV_PEEK_HEADER(data, ehc);
> + if (!eh)
> + return;
>
> if (memcmp(c->guest_mac, eh->h_source, ETH_ALEN)) {
> memcpy(c->guest_mac, eh->h_source, ETH_ALEN);
> proto_update_l2_buf(c->guest_mac, NULL);
> }
>
> + iov_tail_prune(data);
> + ASSERT(data->cnt == 1); /* packet_add() doesn't support iovec */
> +
> switch (ntohs(eh->h_proto)) {
> case ETH_P_ARP:
> case ETH_P_IP:
> - packet_add(pool_tap4, l2len, p);
> + packet_add(pool_tap4, data->iov[0].iov_len - data->off,
> + (char *)data->iov[0].iov_base + data->off);
> break;
> case ETH_P_IPV6:
> - packet_add(pool_tap6, l2len, p);
> + packet_add(pool_tap6, data->iov[0].iov_len - data->off,
> + (char *)data->iov[0].iov_base + data->off);
> break;
> default:
> break;
> @@ -1128,6 +1135,7 @@ static void tap_passt_input(struct ctx *c, const struct timespec *now)
>
> while (n >= (ssize_t)sizeof(uint32_t)) {
> uint32_t l2len = ntohl_unaligned(p);
> + struct iov_tail data;
>
> if (l2len < sizeof(struct ethhdr) || l2len > L2_MAX_LEN_PASST) {
> err("Bad frame size from guest, resetting connection");
> @@ -1142,7 +1150,8 @@ static void tap_passt_input(struct ctx *c, const struct timespec *now)
> p += sizeof(uint32_t);
> n -= sizeof(uint32_t);
>
> - tap_add_packet(c, l2len, p);
> + data = IOV_TAIL_FROM_BUF(p, l2len, 0);
> + tap_add_packet(c, &data);
>
> p += l2len;
> n -= l2len;
> @@ -1186,6 +1195,8 @@ static void tap_pasta_input(struct ctx *c, const struct timespec *now)
> for (n = 0;
> n <= (ssize_t)(sizeof(pkt_buf) - L2_MAX_LEN_PASTA);
> n += len) {
> + struct iov_tail data;
> +
> len = read(c->fd_tap, pkt_buf + n, L2_MAX_LEN_PASTA);
>
> if (len == 0) {
> @@ -1207,7 +1218,8 @@ static void tap_pasta_input(struct ctx *c, const struct timespec *now)
> len > (ssize_t)L2_MAX_LEN_PASTA)
> continue;
>
> - tap_add_packet(c, len, pkt_buf + n);
> + data = IOV_TAIL_FROM_BUF(pkt_buf + n, len, 0);
> + tap_add_packet(c, &data);
> }
>
> tap_handler(c, now);
> diff --git a/tap.h b/tap.h
> index dd39fd896f4a..5034acd8ac46 100644
> --- a/tap.h
> +++ b/tap.h
> @@ -119,6 +119,6 @@ void tap_sock_update_pool(void *base, size_t size);
> void tap_backend_init(struct ctx *c);
> void tap_flush_pools(void);
> void tap_handler(struct ctx *c, const struct timespec *now);
> -void tap_add_packet(struct ctx *c, ssize_t l2len, char *p);
> +void tap_add_packet(struct ctx *c, struct iov_tail *data);
>
> #endif /* TAP_H */
> diff --git a/vu_common.c b/vu_common.c
> index 686a09b28c8e..e446fc4f2054 100644
> --- a/vu_common.c
> +++ b/vu_common.c
> @@ -159,7 +159,6 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
> struct vu_virtq_element elem[VIRTQUEUE_MAX_SIZE];
> struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
> struct vu_virtq *vq = &vdev->vq[index];
> - int hdrlen = sizeof(struct virtio_net_hdr_mrg_rxbuf);
> int out_sg_count;
> int count;
>
> @@ -172,6 +171,7 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
> while (count < VIRTQUEUE_MAX_SIZE &&
> out_sg_count + VU_MAX_TX_BUFFER_NB <= VIRTQUEUE_MAX_SIZE) {
> int ret;
> + struct iov_tail data;
>
> elem[count].out_num = VU_MAX_TX_BUFFER_NB;
> elem[count].out_sg = &out_sg[out_sg_count];
> @@ -187,25 +187,10 @@ static void vu_handle_tx(struct vu_dev *vdev, int index,
> warn("virtio-net transmit queue contains no out buffers");
> break;
> }
> - if (elem[count].out_num == 1) {
> - tap_add_packet(vdev->context,
> - elem[count].out_sg[0].iov_len - hdrlen,
> - (char *)elem[count].out_sg[0].iov_base +
> - hdrlen);
> - } else {
> - /* vnet header can be in a separate iovec */
> - if (elem[count].out_num != 2) {
> - debug("virtio-net transmit queue contains more than one buffer ([%d]: %u)",
> - count, elem[count].out_num);
> - } else if (elem[count].out_sg[0].iov_len != (size_t)hdrlen) {
> - debug("virtio-net transmit queue entry not aligned on hdrlen ([%d]: %d != %zu)",
> - count, hdrlen, elem[count].out_sg[0].iov_len);
> - } else {
> - tap_add_packet(vdev->context,
> - elem[count].out_sg[1].iov_len,
> - (char *)elem[count].out_sg[1].iov_base);
> - }
> - }
> +
> + data = IOV_TAIL(elem[count].out_sg, elem[count].out_num, 0);
> + if (IOV_DROP_HEADER(&data, struct virtio_net_hdr_mrg_rxbuf))
> + tap_add_packet(vdev->context, &data);
>
> count++;
> }
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 04/18] packet: Use iov_tail with packet_add()
2025-04-02 17:23 ` [PATCH 04/18] packet: Use iov_tail with packet_add() Laurent Vivier
@ 2025-04-03 4:54 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 4:54 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 6737 bytes --]
On Wed, Apr 02, 2025 at 07:23:29PM +0200, Laurent Vivier wrote:
Needs at least some sort of commit message.
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
But otherwise,
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> iov.h | 1 +
> packet.c | 15 ++++++++++++---
> packet.h | 8 +++++---
> tap.c | 32 ++++++++++++++++++--------------
> 4 files changed, 36 insertions(+), 20 deletions(-)
>
> diff --git a/iov.h b/iov.h
> index f9b5fdf0803e..99442d031549 100644
> --- a/iov.h
> +++ b/iov.h
> @@ -17,6 +17,7 @@
>
> #include <unistd.h>
> #include <string.h>
> +#include <stdbool.h>
>
> #define IOV_OF_LVALUE(lval) \
> (struct iovec){ .iov_base = &(lval), .iov_len = sizeof(lval) }
> diff --git a/packet.c b/packet.c
> index bcac03750dc0..8b11e0850ff6 100644
> --- a/packet.c
> +++ b/packet.c
> @@ -64,15 +64,16 @@ static int packet_check_range(const struct pool *p, const char *ptr, size_t len,
> /**
> * packet_add_do() - Add data as packet descriptor to given pool
> * @p: Existing pool
> - * @len: Length of new descriptor
> - * @start: Start of data
> + * @data: Data to add
> * @func: For tracing: name of calling function, NULL means no trace()
> * @line: For tracing: caller line of function call
> */
> -void packet_add_do(struct pool *p, size_t len, const char *start,
> +void packet_add_do(struct pool *p, struct iov_tail *data,
> const char *func, int line)
> {
> size_t idx = p->count;
> + const char *start;
> + size_t len;
>
> if (idx >= p->size) {
> trace("add packet index %zu to pool with size %zu, %s:%i",
> @@ -80,6 +81,14 @@ void packet_add_do(struct pool *p, size_t len, const char *start,
> return;
> }
>
> + if (!iov_tail_prune(data))
> + return;
> +
> + ASSERT(data->cnt == 1); /* we don't support iovec */
> +
> + len = data->iov[0].iov_len - data->off;
> + start = (char *)data->iov[0].iov_base + data->off;
> +
> if (packet_check_range(p, start, len, func, line))
> return;
>
> diff --git a/packet.h b/packet.h
> index d099f026631b..f386295da203 100644
> --- a/packet.h
> +++ b/packet.h
> @@ -6,6 +6,8 @@
> #ifndef PACKET_H
> #define PACKET_H
>
> +#include "iov.h"
> +
> /* Maximum size of a single packet stored in pool, including headers */
> #define PACKET_MAX_LEN UINT16_MAX
>
> @@ -28,15 +30,15 @@ struct pool {
> };
>
> int vu_packet_check_range(void *buf, const char *ptr, size_t len);
> -void packet_add_do(struct pool *p, size_t len, const char *start,
> +void packet_add_do(struct pool *p, struct iov_tail *data,
> const char *func, int line);
> void *packet_get_do(const struct pool *p, const size_t idx,
> size_t offset, size_t len, size_t *left,
> const char *func, int line);
> void pool_flush(struct pool *p);
>
> -#define packet_add(p, len, start) \
> - packet_add_do(p, len, start, __func__, __LINE__)
> +#define packet_add(p, data) \
> + packet_add_do(p, data, __func__, __LINE__)
>
> #define packet_get(p, idx, offset, len, left) \
> packet_get_do(p, idx, offset, len, left, __func__, __LINE__)
> diff --git a/tap.c b/tap.c
> index ab3effe80f89..4b54807c4101 100644
> --- a/tap.c
> +++ b/tap.c
> @@ -683,6 +683,7 @@ resume:
> size_t l2len, l3len, hlen, l4len;
> const struct ethhdr *eh;
> const struct udphdr *uh;
> + struct iov_tail data;
> struct iphdr *iph;
> const char *l4h;
>
> @@ -694,7 +695,8 @@ resume:
> if (ntohs(eh->h_proto) == ETH_P_ARP) {
> PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
>
> - packet_add(pkt, l2len, (char *)eh);
> + data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
> + packet_add(pkt, &data);
> arp(c, pkt);
> continue;
> }
> @@ -739,7 +741,8 @@ resume:
>
> tap_packet_debug(iph, NULL, NULL, 0, NULL, 1);
>
> - packet_add(pkt, l4len, l4h);
> + data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
> + packet_add(pkt, &data);
> icmp_tap_handler(c, PIF_TAP, AF_INET,
> &iph->saddr, &iph->daddr,
> pkt, now);
> @@ -753,7 +756,8 @@ resume:
> if (iph->protocol == IPPROTO_UDP) {
> PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
>
> - packet_add(pkt, l2len, (char *)eh);
> + data = IOV_TAIL_FROM_BUF((void *)eh, l2len, 0);
> + packet_add(pkt, &data);
> if (dhcp(c, pkt))
> continue;
> }
> @@ -802,7 +806,8 @@ resume:
> #undef L4_SET
>
> append:
> - packet_add((struct pool *)&seq->p, l4len, l4h);
> + data = IOV_TAIL_FROM_BUF((void *)l4h, l4len, 0);
> + packet_add((struct pool *)&seq->p, &data);
> }
>
> for (j = 0, seq = tap4_l4; j < seq_count; j++, seq++) {
> @@ -858,6 +863,7 @@ resume:
> struct in6_addr *saddr, *daddr;
> const struct ethhdr *eh;
> const struct udphdr *uh;
> + struct iov_tail data;
> struct ipv6hdr *ip6h;
> uint8_t proto;
> char *l4h;
> @@ -911,7 +917,8 @@ resume:
> if (l4len < sizeof(struct icmp6hdr))
> continue;
>
> - packet_add(pkt, l4len, l4h);
> + data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
> + packet_add(pkt, &data);
>
> if (ndp(c, (struct icmp6hdr *)l4h, saddr, pkt))
> continue;
> @@ -930,7 +937,8 @@ resume:
> if (proto == IPPROTO_UDP) {
> PACKET_POOL_P(pkt, 1, in->buf, in->buf_size);
>
> - packet_add(pkt, l4len, l4h);
> + data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
> + packet_add(pkt, &data);
>
> if (dhcpv6(c, pkt, saddr, daddr))
> continue;
> @@ -984,7 +992,8 @@ resume:
> #undef L4_SET
>
> append:
> - packet_add((struct pool *)&seq->p, l4len, l4h);
> + data = IOV_TAIL_FROM_BUF(l4h, l4len, 0);
> + packet_add((struct pool *)&seq->p, &data);
> }
>
> for (j = 0, seq = tap6_l4; j < seq_count; j++, seq++) {
> @@ -1058,18 +1067,13 @@ void tap_add_packet(struct ctx *c, struct iov_tail *data)
> proto_update_l2_buf(c->guest_mac, NULL);
> }
>
> - iov_tail_prune(data);
> - ASSERT(data->cnt == 1); /* packet_add() doesn't support iovec */
> -
> switch (ntohs(eh->h_proto)) {
> case ETH_P_ARP:
> case ETH_P_IP:
> - packet_add(pool_tap4, data->iov[0].iov_len - data->off,
> - (char *)data->iov[0].iov_base + data->off);
> + packet_add(pool_tap4, data);
> break;
> case ETH_P_IPV6:
> - packet_add(pool_tap6, data->iov[0].iov_len - data->off,
> - (char *)data->iov[0].iov_base + data->off);
> + packet_add(pool_tap6, data);
> break;
> default:
> break;
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 05/18] packet: Add packet_base()
2025-04-02 17:23 ` [PATCH 05/18] packet: Add packet_base() Laurent Vivier
@ 2025-04-03 4:59 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 4:59 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 3524 bytes --]
On Wed, Apr 02, 2025 at 07:23:30PM +0200, Laurent Vivier wrote:
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Needs commit message.
> ---
> packet.c | 37 +++++++++++++++++++++++++++++++++++++
> packet.h | 7 +++++++
> 2 files changed, 44 insertions(+)
>
> diff --git a/packet.c b/packet.c
> index 8b11e0850ff6..25ede38b94cb 100644
> --- a/packet.c
> +++ b/packet.c
> @@ -156,6 +156,43 @@ void *packet_get_do(const struct pool *p, size_t idx, size_t offset,
> return ptr;
> }
>
> +/**
> + * packet_base_do() - Get data range from packet descriptor from given pool
> + * @p: Packet pool
> + * @idx: Index of packet descriptor in pool
> + * @func: For tracing: name of calling function, NULL means no trace()
> + * @line: For tracing: caller line of function call
> + *
> + * Return: pointer to start of data range, NULL on invalid range or descriptor
All these comments need to be updated, they seem to be based on (an
old version of?) packet_get_do and are no longer accurate.
"packet_base()" also doesn't really convey the meaning to me. Not
sure what a better name is, though.
> + */
> +/* cppcheck-suppress unusedFunction */
> +bool packet_base_do(const struct pool *p, size_t idx,
> + struct iov_tail *data,
> + const char *func, int line)
> +{
> + size_t i;
> +
> + if (idx >= p->size || idx >= p->count) {
> + if (func) {
> + trace("packet %zu from pool size: %zu, count: %zu, "
> + "%s:%i", idx, p->size, p->count, func, line);
> + }
> + return NULL;
> + }
> +
> + data->cnt = 1;
> + data->off = 0;
> + data->iov = &p->pkt[idx];
> +
> + for (i = 0; i < data->cnt; i++) {
> + if (packet_check_range(p, data->iov[i].iov_base,
> + data->iov[i].iov_len, func, line))
> + return false;
This looks to be based logically on versions of packet_get_do() before
I did my rework in 38bcce997 and surrounding commits. If we get a
packet_check_range() failure here it means the packet pool is already
corrupt and we should just ASSERT.
The conditions on func being non-NULL should also be gone.
> + }
> +
> + return true;
> +}
> +
> /**
> * pool_flush() - Flush a packet pool
> * @p: Pointer to packet pool
> diff --git a/packet.h b/packet.h
> index f386295da203..35058e747a43 100644
> --- a/packet.h
> +++ b/packet.h
> @@ -35,6 +35,9 @@ void packet_add_do(struct pool *p, struct iov_tail *data,
> void *packet_get_do(const struct pool *p, const size_t idx,
> size_t offset, size_t len, size_t *left,
> const char *func, int line);
> +bool packet_base_do(const struct pool *p, const size_t idx,
> + struct iov_tail *data,
> + const char *func, int line);
> void pool_flush(struct pool *p);
>
> #define packet_add(p, data) \
> @@ -43,9 +46,13 @@ void pool_flush(struct pool *p);
> #define packet_get(p, idx, offset, len, left) \
> packet_get_do(p, idx, offset, len, left, __func__, __LINE__)
>
> +
> #define packet_get_try(p, idx, offset, len, left) \
> packet_get_do(p, idx, offset, len, left, NULL, 0)
>
> +#define packet_base(p, idx, data) \
> + packet_base_do(p, idx, data, __func__, __LINE__)
> +
> #define PACKET_POOL_DECL(_name, _size, _buf) \
> struct _name ## _t { \
> char *buf; \
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 06/18] arp: Convert to iov_tail
2025-04-02 17:23 ` [PATCH 06/18] arp: Convert to iov_tail Laurent Vivier
@ 2025-04-03 5:00 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:00 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 1860 bytes --]
On Wed, Apr 02, 2025 at 07:23:31PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_REMOVE_HEADER()
> rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> arp.c | 12 +++++++++---
> packet.c | 1 -
> 2 files changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/arp.c b/arp.c
> index 9d68d7c3b602..cd0e15de7de0 100644
> --- a/arp.c
> +++ b/arp.c
> @@ -77,11 +77,17 @@ int arp(const struct ctx *c, const struct pool *p)
> const struct ethhdr *eh;
> const struct arphdr *ah;
> const struct arpmsg *am;
> + struct iov_tail data;
> + struct arphdr ahc;
> + struct ethhdr ehc;
> + struct arpmsg amc;
>
> - eh = packet_get(p, 0, 0, sizeof(*eh), NULL);
> - ah = packet_get(p, 0, sizeof(*eh), sizeof(*ah), NULL);
> - am = packet_get(p, 0, sizeof(*eh) + sizeof(*ah), sizeof(*am), NULL);
> + if (!packet_base(p, 0, &data))
> + return -1;
>
> + eh = IOV_REMOVE_HEADER(&data, ehc);
> + ah = IOV_REMOVE_HEADER(&data, ahc);
> + am = IOV_REMOVE_HEADER(&data, amc);
> if (!eh || !ah || !am)
> return -1;
>
> diff --git a/packet.c b/packet.c
> index 25ede38b94cb..8066ac12502b 100644
> --- a/packet.c
> +++ b/packet.c
> @@ -165,7 +165,6 @@ void *packet_get_do(const struct pool *p, size_t idx, size_t offset,
> *
> * Return: pointer to start of data range, NULL on invalid range or descriptor
> */
> -/* cppcheck-suppress unusedFunction */
> bool packet_base_do(const struct pool *p, size_t idx,
> struct iov_tail *data,
> const char *func, int line)
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 07/18] ndp: Convert to iov_tail
2025-04-02 17:23 ` [PATCH 07/18] ndp: " Laurent Vivier
@ 2025-04-03 5:01 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:01 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 1073 bytes --]
On Wed, Apr 02, 2025 at 07:23:32PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_REMOVE_HEADER()
> rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
> ---
> ndp.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/ndp.c b/ndp.c
> index ded2081ddd1d..64e25d5455b4 100644
> --- a/ndp.c
> +++ b/ndp.c
> @@ -351,8 +351,13 @@ int ndp(const struct ctx *c, const struct icmp6hdr *ih,
>
> if (ih->icmp6_type == NS) {
> const struct ndp_ns *ns;
> + struct iov_tail data;
> + struct ndp_ns nsc;
>
> - ns = packet_get(p, 0, 0, sizeof(struct ndp_ns), NULL);
> + if (!packet_base(p, 0, &data))
> + return -1;
> +
> + ns = IOV_REMOVE_HEADER(&data, nsc);
> if (!ns)
> return -1;
>
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 08/18] icmp: Convert to iov_tail
2025-04-02 17:23 ` [PATCH 08/18] icmp: " Laurent Vivier
@ 2025-04-03 5:04 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:04 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 2864 bytes --]
On Wed, Apr 02, 2025 at 07:23:33PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_PEEK_HEADER()
> rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> icmp.c | 38 +++++++++++++++++++++++---------------
> 1 file changed, 23 insertions(+), 15 deletions(-)
>
> diff --git a/icmp.c b/icmp.c
> index 7e2b3423a8d1..119502c0c340 100644
> --- a/icmp.c
> +++ b/icmp.c
> @@ -241,24 +241,25 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
> struct icmp_ping_flow *pingf;
> const struct flowside *tgt;
> union sockaddr_inany sa;
> - size_t dlen, l4len;
> + struct iov_tail data;
> + struct msghdr msh;
> uint16_t id, seq;
> union flow *flow;
> uint8_t proto;
> - socklen_t sl;
> - void *pkt;
>
> (void)saddr;
> ASSERT(pif == PIF_TAP);
>
> + if (!packet_base(p, 0, &data))
> + return -1;
> +
> if (af == AF_INET) {
> const struct icmphdr *ih;
> + struct icmphdr ihc;
>
> - if (!(pkt = packet_get(p, 0, 0, sizeof(*ih), &dlen)))
> - return 1;
> -
> - ih = (struct icmphdr *)pkt;
> - l4len = dlen + sizeof(*ih);
> + ih = IOV_PEEK_HEADER(&data, ihc);
> + if (!ih)
> + return -1;
>
> if (ih->type != ICMP_ECHO)
> return 1;
> @@ -268,12 +269,11 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
> seq = ntohs(ih->un.echo.sequence);
> } else if (af == AF_INET6) {
> const struct icmp6hdr *ih;
> + struct icmp6hdr ihc;
>
> - if (!(pkt = packet_get(p, 0, 0, sizeof(*ih), &dlen)))
> - return 1;
> -
> - ih = (struct icmp6hdr *)pkt;
> - l4len = dlen + sizeof(*ih);
> + ih = IOV_PEEK_HEADER(&data, ihc);
> + if (!ih)
> + return -1;
>
> if (ih->icmp6_type != ICMPV6_ECHO_REQUEST)
> return 1;
> @@ -298,8 +298,16 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
> ASSERT(flow_proto[pingf->f.type] == proto);
> pingf->ts = now->tv_sec;
>
> - pif_sockaddr(c, &sa, &sl, PIF_HOST, &tgt->eaddr, 0);
> - if (sendto(pingf->sock, pkt, l4len, MSG_NOSIGNAL, &sa.sa, sl) < 0) {
> + ASSERT(data.off == 0);
> + msh.msg_name = &sa;
> + msh.msg_iov = (struct iovec *)data.iov;
> + msh.msg_iovlen = data.cnt;
> + msh.msg_control = NULL;
> + msh.msg_controllen = 0;
> + msh.msg_flags = 0;
I think we're going to want a helper to build a msghdr from an iov_tail.
> +
> + pif_sockaddr(c, &sa, &msh.msg_namelen, PIF_HOST, &tgt->eaddr, 0);
> + if (sendmsg(pingf->sock, &msh, MSG_NOSIGNAL) < 0) {
> flow_dbg_perror(pingf, "failed to relay request to socket");
> } else {
> flow_dbg(pingf,
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 09/18] udp: Convert to iov_tail
2025-04-02 17:23 ` [PATCH 09/18] udp: " Laurent Vivier
@ 2025-04-03 5:11 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:11 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 3708 bytes --]
On Wed, Apr 02, 2025 at 07:23:34PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_REMOVE_HEADER()
> and IOV_PEEK_HEADER() rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> iov.c | 1 -
> udp.c | 37 ++++++++++++++++++++++++++-----------
> 2 files changed, 26 insertions(+), 12 deletions(-)
>
> diff --git a/iov.c b/iov.c
> index 508fb6da91fb..0c69379316aa 100644
> --- a/iov.c
> +++ b/iov.c
> @@ -173,7 +173,6 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt)
> * Returns: The number of elements successfully copied to the destination
> * iov array.
> */
> -/* cppcheck-suppress unusedFunction */
> unsigned iov_copy(struct iovec *dst_iov, size_t dst_iov_cnt,
> const struct iovec *iov, size_t iov_cnt,
> size_t offset, size_t bytes)
> diff --git a/udp.c b/udp.c
> index 80520cbdf188..03906d72e75c 100644
> --- a/udp.c
> +++ b/udp.c
> @@ -858,15 +858,20 @@ int udp_tap_handler(const struct ctx *c, uint8_t pif,
> struct iovec m[UIO_MAXIOV];
> const struct udphdr *uh;
> struct udp_flow *uflow;
> - int i, s, count = 0;
> + int i, j, s, count = 0;
> + struct iov_tail data;
> flow_sidx_t tosidx;
> in_port_t src, dst;
> + struct udphdr uhc;
> uint8_t topif;
> socklen_t sl;
>
> ASSERT(!c->no_udp);
>
> - uh = packet_get(p, idx, 0, sizeof(*uh), NULL);
> + if (!packet_base(p, idx, &data))
> + return 1;
> +
> + uh = IOV_PEEK_HEADER(&data, uhc);
> if (!uh)
> return 1;
>
> @@ -903,23 +908,33 @@ int udp_tap_handler(const struct ctx *c, uint8_t pif,
>
> pif_sockaddr(c, &to_sa, &sl, topif, &toside->eaddr, toside->eport);
>
> - for (i = 0; i < (int)p->count - idx; i++) {
> - struct udphdr *uh_send;
> - size_t len;
> + for (i = 0, j = 0; i < (int)p->count - idx && j < UIO_MAXIOV; i++) {
> + const struct udphdr *uh_send;
> +
> + if (!packet_base(p, idx + i, &data))
> + return p->count - idx;
>
> - uh_send = packet_get(p, idx + i, 0, sizeof(*uh), &len);
> + uh_send = IOV_REMOVE_HEADER(&data, uhc);
> if (!uh_send)
> return p->count - idx;
>
> + iov_tail_prune(&data);
Maybe we should make remove_header always prune, rather than having to
do it manually.
> +
> + if (data.cnt + j >= UIO_MAXIOV)
Obviously it's equivalent, but this would make more intuitive sense to
me as (j + data.cnt): the amount we've already used in our array, plus
the extra we're going to need.
> + return p->count - idx;
> +
> mm[i].msg_hdr.msg_name = &to_sa;
> mm[i].msg_hdr.msg_namelen = sl;
>
> - if (len) {
> - m[i].iov_base = (char *)(uh_send + 1);
> - m[i].iov_len = len;
> + if (data.cnt ) {
Stray space.
> + unsigned int len;
> +
> + len = iov_copy(&m[j], UIO_MAXIOV - j,
> + &data.iov[0], data.cnt, data.off, SIZE_MAX);
So, as I mentioned on iov_copy(), it doesn't obviously report the case
where it copies less than expected not because the source is missing
data, but because the destination doesn't have enough iovecs. You've
avoided this case with a test above, but that's a bit non-obvious, it
would be nice if we could just call this and check for an error.
> - mm[i].msg_hdr.msg_iov = m + i;
> - mm[i].msg_hdr.msg_iovlen = 1;
> + mm[i].msg_hdr.msg_iov = &m[j];
> + mm[i].msg_hdr.msg_iovlen = len;
> + j += len;
> } else {
> mm[i].msg_hdr.msg_iov = NULL;
> mm[i].msg_hdr.msg_iovlen = 0;
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 10/18] tcp: Convert tcp_tap_handler() to use iov_tail
2025-04-02 17:23 ` [PATCH 10/18] tcp: Convert tcp_tap_handler() to use iov_tail Laurent Vivier
@ 2025-04-03 5:14 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:14 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 2141 bytes --]
On Wed, Apr 02, 2025 at 07:23:35PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_REMOVE_HEADER()
> and iov_peek_header_() rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> tcp.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/tcp.c b/tcp.c
> index a4c840e6721c..790714a08793 100644
> --- a/tcp.c
> +++ b/tcp.c
> @@ -310,6 +310,8 @@
> #include "tcp_buf.h"
> #include "tcp_vu.h"
>
Some explanation of the derivation would be good here.
> +#define OPTLEN_MAX (((1UL << 4) - 6) * 4UL)
> +
> #ifndef __USE_MISC
> /* From Linux UAPI, missing in netinet/tcp.h provided by musl */
> struct tcp_repair_opt {
> @@ -1957,7 +1959,10 @@ int tcp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
> {
> struct tcp_tap_conn *conn;
> const struct tcphdr *th;
> + char optsc[OPTLEN_MAX];
> + struct iov_tail data;
> size_t optlen, len;
> + struct tcphdr thc;
> const char *opts;
> union flow *flow;
> flow_sidx_t sidx;
> @@ -1966,15 +1971,19 @@ int tcp_tap_handler(const struct ctx *c, uint8_t pif, sa_family_t af,
>
> (void)pif;
>
> - th = packet_get(p, idx, 0, sizeof(*th), &len);
> + if (!packet_base(p, idx, &data))
> + return 1;
> +
> + len = iov_tail_size(&data);
'l4len', please.
> +
> + th = IOV_REMOVE_HEADER(&data, thc);
> if (!th)
> return 1;
> - len += sizeof(*th);
>
> optlen = th->doff * 4UL - sizeof(*th);
> /* Static checkers might fail to see this: */
> - optlen = MIN(optlen, ((1UL << 4) /* from doff width */ - 6) * 4UL);
> - opts = packet_get(p, idx, sizeof(*th), optlen, NULL);
> + optlen = MIN(optlen, OPTLEN_MAX);
> + opts = (char *)iov_peek_header_(&data, &optsc[0], optlen, 1);
>
> sidx = flow_lookup_af(c, IPPROTO_TCP, PIF_TAP, af, saddr, daddr,
> ntohs(th->source), ntohs(th->dest));
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 11/18] tcp: Convert tcp_data_from_tap() to use iov_tail
2025-04-02 17:23 ` [PATCH 11/18] tcp: Convert tcp_data_from_tap() " Laurent Vivier
@ 2025-04-03 5:20 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:20 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 2588 bytes --]
On Wed, Apr 02, 2025 at 07:23:36PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_PEEK_HEADER()
> rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> tcp.c | 24 ++++++++++++++----------
> 1 file changed, 14 insertions(+), 10 deletions(-)
>
> diff --git a/tcp.c b/tcp.c
> index 790714a08793..a9c04551d9d6 100644
> --- a/tcp.c
> +++ b/tcp.c
> @@ -1643,14 +1643,19 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
> for (i = idx, iov_i = 0; i < (int)p->count; i++) {
> uint32_t seq, seq_offset, ack_seq;
> const struct tcphdr *th;
> - char *data;
> + struct iov_tail data;
> + unsigned int count;
> + struct tcphdr thc;
> size_t off;
>
> - th = packet_get(p, i, 0, sizeof(*th), &len);
> + if (!packet_base(p, i, &data))
> + return -1;
> +
> + th = IOV_PEEK_HEADER(&data, thc);
> if (!th)
> return -1;
> - len += sizeof(*th);
>
> + len = iov_tail_size(&data);
> off = th->doff * 4UL;
> if (off < sizeof(*th) || off > len)
> return -1;
> @@ -1661,9 +1666,7 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
> }
>
> len -= off;
> - data = packet_get(p, i, off, len, NULL);
> - if (!data)
> - continue;
> + data.off = off;
You can use iov_drop() rather than reaching into the internals of
iov_tail here, no?
> seq = ntohl(th->seq);
> if (SEQ_LT(seq, conn->seq_from_tap) && len <= 1) {
> @@ -1737,10 +1740,11 @@ static int tcp_data_from_tap(const struct ctx *c, struct tcp_tap_conn *conn,
> continue;
> }
>
> - tcp_iov[iov_i].iov_base = data + seq_offset;
> - tcp_iov[iov_i].iov_len = len - seq_offset;
> - seq_from_tap += tcp_iov[iov_i].iov_len;
> - iov_i++;
> + count = iov_copy(&tcp_iov[iov_i], UIO_MAXIOV - iov_i,
> + &data.iov[0], data.cnt, data.off + seq_offset,
> + len - seq_offset);
Here again it matters if you run out of space in the destination iov,
and I don't think you have a check above which prevents it.
> + seq_from_tap += iov_size(&tcp_iov[iov_i], count);
We already called iov_size() on &data above. We should be able to
derive the total length here from that minus headers, without having
to recount the IOV, no?
> + iov_i += count;
>
> if (keep == i)
> keep = -1;
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 12/18] dhcpv6: Convert to iov_tail
2025-04-02 17:23 ` [PATCH 12/18] dhcpv6: Convert to iov_tail Laurent Vivier
@ 2025-04-03 5:21 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:21 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 1715 bytes --]
On Wed, Apr 02, 2025 at 07:23:37PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_REMOVE_HEADER()
> and IOV_PEEK_HEADER() rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> dhcpv6.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/dhcpv6.c b/dhcpv6.c
> index 373a98869f9b..eb3f188af0b5 100644
> --- a/dhcpv6.c
> +++ b/dhcpv6.c
> @@ -496,9 +496,15 @@ int dhcpv6(struct ctx *c, const struct pool *p,
> const struct msg_hdr *mh;
> const struct udphdr *uh;
> struct opt_hdr *bad_ia;
> + struct iov_tail data;
> + struct msg_hdr mhc;
> + struct udphdr uhc;
> size_t mlen, n;
>
> - uh = packet_get(p, 0, 0, sizeof(*uh), &mlen);
> + if (!packet_base(p, 0, &data))
> + return -1;
> +
> + uh = IOV_REMOVE_HEADER(&data, uhc);
> if (!uh)
> return -1;
>
> @@ -511,6 +517,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
> if (!IN6_IS_ADDR_MULTICAST(daddr))
> return -1;
>
> + mlen = iov_tail_size(&data);
The total length is useful in enough cases that I wonder if it makes
sense for packet_base() to return it.
> if (mlen + sizeof(*uh) != ntohs(uh->len) || mlen < sizeof(*mh))
> return -1;
>
> @@ -518,7 +525,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
>
> src = &c->ip6.our_tap_ll;
>
> - mh = packet_get(p, 0, sizeof(*uh), sizeof(*mh), NULL);
> + mh = IOV_PEEK_HEADER(&data, mhc);
> if (!mh)
> return -1;
>
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 13/18] dhcpv6: move offset initialization out of dhcpv6_opt()
2025-04-02 17:23 ` [PATCH 13/18] dhcpv6: move offset initialization out of dhcpv6_opt() Laurent Vivier
@ 2025-04-03 5:25 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:25 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 3658 bytes --]
On Wed, Apr 02, 2025 at 07:23:38PM +0200, Laurent Vivier wrote:
Needs a commit message.
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> dhcpv6.c | 22 +++++++++++-----------
> 1 file changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/dhcpv6.c b/dhcpv6.c
> index eb3f188af0b5..ccc64172a480 100644
> --- a/dhcpv6.c
> +++ b/dhcpv6.c
> @@ -54,14 +54,14 @@ struct opt_hdr {
> uint16_t l;
> } __attribute__((packed));
>
> +#define UDP_MSG_HDR_SIZE (sizeof(struct udphdr) + sizeof(struct msg_hdr))
> # define OPT_SIZE_CONV(x) (htons_constant(x))
> #define OPT_SIZE(x) OPT_SIZE_CONV(sizeof(struct opt_##x) - \
> sizeof(struct opt_hdr))
> #define OPT_VSIZE(x) (sizeof(struct opt_##x) - \
> sizeof(struct opt_hdr))
> #define OPT_MAX_SIZE IPV6_MIN_MTU - (sizeof(struct ipv6hdr) + \
> - sizeof(struct udphdr) + \
> - sizeof(struct msg_hdr))
> + UDP_MSG_HDR_SIZE)
>
> /**
> * struct opt_client_id - DHCPv6 Client Identifier option
> @@ -290,8 +290,7 @@ static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
> struct opt_hdr *o;
> size_t left;
>
> - if (!*offset)
> - *offset = sizeof(struct udphdr) + sizeof(struct msg_hdr);
> + ASSERT(*offset >= UDP_MSG_HDR_SIZE);
>
> while ((o = packet_get_try(p, 0, *offset, sizeof(*o), &left))) {
> unsigned int opt_len = ntohs(o->l) + sizeof(*o);
> @@ -327,7 +326,7 @@ static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
> size_t offset;
>
> foreach(ia_type, ia_types) {
> - offset = 0;
> + offset = UDP_MSG_HDR_SIZE;
> while ((ia = dhcpv6_opt(p, &offset, *ia_type))) {
> if (ntohs(ia->l) < OPT_VSIZE(ia_na))
> return NULL;
> @@ -464,8 +463,9 @@ static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
>
> o = (struct opt_client_fqdn *)(buf + offset);
> encode_domain_name(o->domain_name, c->fqdn);
> - req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p, &(size_t){ 0 },
> - OPT_CLIENT_FQDN);
> + req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p,
> + &(size_t){ UDP_MSG_HDR_SIZE },
> + OPT_CLIENT_FQDN);
> if (req_opt && req_opt->flags & 0x01 /* S flag */)
> o->flags = 0x02 /* O flag */;
> else
> @@ -529,15 +529,15 @@ int dhcpv6(struct ctx *c, const struct pool *p,
> if (!mh)
> return -1;
>
> - client_id = dhcpv6_opt(p, &(size_t){ 0 }, OPT_CLIENTID);
> + client_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_CLIENTID);
> if (!client_id || ntohs(client_id->l) > OPT_VSIZE(client_id))
> return -1;
>
> - server_id = dhcpv6_opt(p, &(size_t){ 0 }, OPT_SERVERID);
> + server_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_SERVERID);
> if (server_id && ntohs(server_id->l) != OPT_VSIZE(server_id))
> return -1;
>
> - ia = dhcpv6_opt(p, &(size_t){ 0 }, OPT_IA_NA);
> + ia = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_NA);
> if (ia && ntohs(ia->l) < MIN(OPT_VSIZE(ia_na), OPT_VSIZE(ia_ta)))
> return -1;
>
> @@ -587,7 +587,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
> memcmp(&resp.server_id, server_id, sizeof(resp.server_id)))
> return -1;
>
> - if (ia || dhcpv6_opt(p, &(size_t){ 0 }, OPT_IA_TA))
> + if (ia || dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_TA))
> return -1;
>
> info("DHCPv6: received INFORMATION_REQUEST, sending REPLY");
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 14/18] dhcpv6: Use iov_tail in dhcpv6_opt()
2025-04-02 17:23 ` [PATCH 14/18] dhcpv6: Use iov_tail in dhcpv6_opt() Laurent Vivier
@ 2025-04-03 5:37 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:37 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 7102 bytes --]
On Wed, Apr 02, 2025 at 07:23:39PM +0200, Laurent Vivier wrote:
Needs a commit message.
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> dhcpv6.c | 57 +++++++++++++++++++++++++++-----------------------------
> 1 file changed, 27 insertions(+), 30 deletions(-)
>
> diff --git a/dhcpv6.c b/dhcpv6.c
> index ccc64172a480..1e83f2c2ad23 100644
> --- a/dhcpv6.c
> +++ b/dhcpv6.c
> @@ -278,30 +278,25 @@ static struct resp_not_on_link_t {
>
> /**
> * dhcpv6_opt() - Get option from DHCPv6 message
> - * @p: Packet pool, single packet with UDP header
> - * @offset: Offset to look at, 0: end of header, set to option start
> + * @data: Data to look at
> * @type: Option type to look up, network order
> *
> * Return: pointer to option header, or NULL on malformed or missing option
> */
> -static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
> - uint16_t type)
> +static struct opt_hdr *dhcpv6_opt(struct iov_tail *data, uint16_t type)
> {
> - struct opt_hdr *o;
> - size_t left;
> + struct opt_hdr *o, oc;
>
> - ASSERT(*offset >= UDP_MSG_HDR_SIZE);
> -
> - while ((o = packet_get_try(p, 0, *offset, sizeof(*o), &left))) {
> + while ((o = IOV_PEEK_HEADER(data, oc))) {
> unsigned int opt_len = ntohs(o->l) + sizeof(*o);
>
> - if (ntohs(o->l) > left)
> + if (opt_len > iov_tail_size(data))
> return NULL;
>
> if (o->t == type)
> return o;
This is no good. If peek_header() ended up copying the header you'll
now be returning a pointer to a local variable.
Also, you've only verified the contiguity of the option header with
IOV_PEEK_HEADER, the body of the option could still be discontiguous,
which is not what the callers expect.
> - *offset += opt_len;
> + data->off += opt_len;
I think you want iov_drop() or REMOVE_HEADER() here rather than
reaching into the iov_tail structure.
> }
>
> return NULL;
> @@ -309,31 +304,31 @@ static struct opt_hdr *dhcpv6_opt(const struct pool *p, size_t *offset,
>
> /**
> * dhcpv6_ia_notonlink() - Check if any IA contains non-appropriate addresses
> - * @p: Packet pool, single packet starting from UDP header
> + * @data: Data to look at, packet starting from UDP header
> * @la: Address we want to lease to the client
> *
> * Return: pointer to non-appropriate IA_NA or IA_TA, if any, NULL otherwise
> */
> -static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
> +static struct opt_hdr *dhcpv6_ia_notonlink(const struct iov_tail *data,
> struct in6_addr *la)
> {
> int ia_types[2] = { OPT_IA_NA, OPT_IA_TA }, *ia_type;
> const struct opt_ia_addr *opt_addr;
> char buf[INET6_ADDRSTRLEN];
> struct in6_addr req_addr;
> + struct iov_tail current;
> const struct opt_hdr *h;
> struct opt_hdr *ia;
> - size_t offset;
>
> foreach(ia_type, ia_types) {
> - offset = UDP_MSG_HDR_SIZE;
> - while ((ia = dhcpv6_opt(p, &offset, *ia_type))) {
> + current = *data;
> + while ((ia = dhcpv6_opt(¤t, *ia_type))) {
> if (ntohs(ia->l) < OPT_VSIZE(ia_na))
> return NULL;
>
> - offset += sizeof(struct opt_ia_na);
> + current.off += sizeof(struct opt_ia_na);
>
> - while ((h = dhcpv6_opt(p, &offset, OPT_IAAADR))) {
> + while ((h = dhcpv6_opt(¤t, OPT_IAAADR))) {
> if (ntohs(h->l) != OPT_VSIZE(ia_addr))
> return NULL;
>
> @@ -342,7 +337,7 @@ static struct opt_hdr *dhcpv6_ia_notonlink(const struct pool *p,
> if (!IN6_ARE_ADDR_EQUAL(la, &req_addr))
> goto err;
>
> - offset += sizeof(struct opt_ia_addr);
> + current.off += sizeof(struct opt_ia_addr);
> }
> }
> }
> @@ -434,13 +429,15 @@ search:
>
> /**
> * dhcpv6_client_fqdn_fill() - Fill in client FQDN option
> + * @data: Data to look at
> * @c: Execution context
> * @buf: Response message buffer where options will be appended
> * @offset: Offset in message buffer for new options
> *
> * Return: updated length of response message buffer.
> */
> -static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
> +static size_t dhcpv6_client_fqdn_fill(struct iov_tail *data,
> + const struct ctx *c,
> char *buf, int offset)
>
> {
> @@ -463,9 +460,8 @@ static size_t dhcpv6_client_fqdn_fill(const struct pool *p, const struct ctx *c,
>
> o = (struct opt_client_fqdn *)(buf + offset);
> encode_domain_name(o->domain_name, c->fqdn);
> - req_opt = (struct opt_client_fqdn *)dhcpv6_opt(p,
> - &(size_t){ UDP_MSG_HDR_SIZE },
> - OPT_CLIENT_FQDN);
> + data->off += UDP_MSG_HDR_SIZE;
> + req_opt = (struct opt_client_fqdn *)dhcpv6_opt(data, OPT_CLIENT_FQDN);
> if (req_opt && req_opt->flags & 0x01 /* S flag */)
> o->flags = 0x02 /* O flag */;
> else
> @@ -525,19 +521,19 @@ int dhcpv6(struct ctx *c, const struct pool *p,
>
> src = &c->ip6.our_tap_ll;
>
> - mh = IOV_PEEK_HEADER(&data, mhc);
> + mh = IOV_REMOVE_HEADER(&data, mhc);
> if (!mh)
> return -1;
>
> - client_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_CLIENTID);
> + client_id = dhcpv6_opt(&data, OPT_CLIENTID);
> if (!client_id || ntohs(client_id->l) > OPT_VSIZE(client_id))
> return -1;
>
> - server_id = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_SERVERID);
> + server_id = dhcpv6_opt(&data, OPT_SERVERID);
> if (server_id && ntohs(server_id->l) != OPT_VSIZE(server_id))
> return -1;
>
> - ia = dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_NA);
> + ia = dhcpv6_opt(&data, OPT_IA_NA);
> if (ia && ntohs(ia->l) < MIN(OPT_VSIZE(ia_na), OPT_VSIZE(ia_ta)))
> return -1;
>
> @@ -553,7 +549,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
> if (mh->type == TYPE_CONFIRM && server_id)
> return -1;
>
> - if ((bad_ia = dhcpv6_ia_notonlink(p, &c->ip6.addr))) {
> + if ((bad_ia = dhcpv6_ia_notonlink(&data, &c->ip6.addr))) {
> info("DHCPv6: received CONFIRM with inappropriate IA,"
> " sending NotOnLink status in REPLY");
>
> @@ -587,7 +583,7 @@ int dhcpv6(struct ctx *c, const struct pool *p,
> memcmp(&resp.server_id, server_id, sizeof(resp.server_id)))
> return -1;
>
> - if (ia || dhcpv6_opt(p, &(size_t){ UDP_MSG_HDR_SIZE }, OPT_IA_TA))
> + if (ia || dhcpv6_opt(&data, OPT_IA_TA))
> return -1;
>
> info("DHCPv6: received INFORMATION_REQUEST, sending REPLY");
> @@ -619,7 +615,8 @@ int dhcpv6(struct ctx *c, const struct pool *p,
> n = offsetof(struct resp_t, client_id) +
> sizeof(struct opt_hdr) + ntohs(client_id->l);
> n = dhcpv6_dns_fill(c, (char *)&resp, n);
> - n = dhcpv6_client_fqdn_fill(p, c, (char *)&resp, n);
> + packet_base(p, 0, &data);
> + n = dhcpv6_client_fqdn_fill(&data, c, (char *)&resp, n);
>
> resp.hdr.xid = mh->xid;
>
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
* Re: [PATCH 15/18] dhcp: Convert to iov_tail
2025-04-02 17:23 ` [PATCH 15/18] dhcp: Convert to iov_tail Laurent Vivier
@ 2025-04-03 5:47 ` David Gibson
0 siblings, 0 replies; 34+ messages in thread
From: David Gibson @ 2025-04-03 5:47 UTC (permalink / raw)
To: Laurent Vivier; +Cc: passt-dev
[-- Attachment #1: Type: text/plain, Size: 3912 bytes --]
On Wed, Apr 02, 2025 at 07:23:40PM +0200, Laurent Vivier wrote:
> Use packet_base() and extract headers using IOV_REMOVE_HEADER()
> and IOV_PEEK_HEADER() rather than packet_get().
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
> dhcp.c | 38 ++++++++++++++++++++++----------------
> iov.c | 1 -
> 2 files changed, 22 insertions(+), 17 deletions(-)
>
> diff --git a/dhcp.c b/dhcp.c
> index b0de04be6f27..f3167beb18b7 100644
> --- a/dhcp.c
> +++ b/dhcp.c
> @@ -302,27 +302,32 @@ static void opt_set_dns_search(const struct ctx *c, size_t max_len)
> */
> int dhcp(const struct ctx *c, const struct pool *p)
> {
> - size_t mlen, dlen, offset = 0, opt_len, opt_off = 0;
> + size_t mlen, dlen, opt_len, opt_off = 0;
> char macstr[ETH_ADDRSTRLEN];
> struct in_addr mask, dst;
> const struct ethhdr *eh;
> const struct iphdr *iph;
> const struct udphdr *uh;
> + struct iov_tail data;
> struct msg const *m;
> + struct msg mc;
> + struct ethhdr ehc;
> + struct iphdr iphc;
> + struct udphdr uhc;
> struct msg reply;
> unsigned int i;
>
> - eh = packet_get(p, 0, offset, sizeof(*eh), NULL);
> - offset += sizeof(*eh);
> + if (!packet_base(p, 0, &data))
> + return -1;
>
> - iph = packet_get(p, 0, offset, sizeof(*iph), NULL);
> + eh = IOV_REMOVE_HEADER(&data, ehc);
> + iph = IOV_PEEK_HEADER(&data, iphc);
> if (!eh || !iph)
> return -1;
>
> - offset += iph->ihl * 4UL;
> - uh = packet_get(p, 0, offset, sizeof(*uh), &mlen);
> - offset += sizeof(*uh);
> + data.off += iph->ihl * 4UL;
iov_drop().
> + uh = IOV_REMOVE_HEADER(&data, uhc);
> if (!uh)
> return -1;
>
> @@ -332,7 +337,9 @@ int dhcp(const struct ctx *c, const struct pool *p)
> if (c->no_dhcp)
> return 1;
>
> - m = packet_get(p, 0, offset, offsetof(struct msg, o), &opt_len);
> + mlen = iov_tail_size(&data);
> + m = (struct msg const *)iov_remove_header_(&data, &mc, offsetof(struct msg, o),
> + __alignof__(struct msg));
> if (!m ||
> mlen != ntohs(uh->len) - sizeof(*uh) ||
> mlen < offsetof(struct msg, o) ||
> @@ -355,25 +362,24 @@ int dhcp(const struct ctx *c, const struct pool *p)
> memset(&reply.file, 0, sizeof(reply.file));
> reply.magic = m->magic;
>
> - offset += offsetof(struct msg, o);
> -
> for (i = 0; i < ARRAY_SIZE(opts); i++)
> opts[i].clen = -1;
>
> + opt_len = iov_tail_size(&data);
> while (opt_off + 2 < opt_len) {
> - const uint8_t *olen, *val;
> + const uint8_t *olen;
> uint8_t *type;
>
> - type = packet_get(p, 0, offset + opt_off, 1, NULL);
> - olen = packet_get(p, 0, offset + opt_off + 1, 1, NULL);
> + type = iov_tail_ptr(&data, opt_off, 1);
> + olen = iov_tail_ptr(&data, opt_off + 1, 1);
I think you can and should use remove_header() for this as well.
> if (!type || !olen)
> return -1;
>
> - val = packet_get(p, 0, offset + opt_off + 2, *olen, NULL);
> - if (!val)
> + if (iov_tail_size(&data) < opt_off + 2 + *olen)
> return -1;
>
> - memcpy(&opts[*type].c, val, *olen);
> + iov_to_buf(&data.iov[0], data.cnt, data.off + opt_off + 2,
> + &opts[*type].c, *olen);
> opts[*type].clen = *olen;
> opt_off += *olen + 2;
> }
> diff --git a/iov.c b/iov.c
> index 0c69379316aa..66f15585a61a 100644
> --- a/iov.c
> +++ b/iov.c
> @@ -253,7 +253,6 @@ bool iov_drop(struct iov_tail *tail, size_t len)
> * Returns: pointer to the data in the tail, NULL if the
> * tail doesn't contains @len bytes.
> */
> -/* cppcheck-suppress unusedFunction */
> void *iov_tail_ptr(struct iov_tail *tail, size_t off, size_t len)
> {
> const struct iovec *iov;
--
David Gibson (he or they) | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you, not the other way
| around.
http://www.ozlabs.org/~dgibson
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 34+ messages in thread
end of thread, other threads:[~2025-04-03 9:16 UTC | newest]
Thread overview: 34+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2025-04-02 17:23 [PATCH 00/18] Introduce discontiguous frames management Laurent Vivier
2025-04-02 17:23 ` [PATCH 01/18] arp: Don't mix incoming and outgoing buffers Laurent Vivier
2025-04-03 1:57 ` David Gibson
2025-04-02 17:23 ` [PATCH 02/18] iov: Update IOV_REMOVE_HEADER() and IOV_PEEK_HEADER() Laurent Vivier
2025-04-03 2:36 ` David Gibson
2025-04-02 17:23 ` [PATCH 03/18] tap: Use iov_tail with tap_add_packet() Laurent Vivier
2025-04-03 4:50 ` David Gibson
2025-04-02 17:23 ` [PATCH 04/18] packet: Use iov_tail with packet_add() Laurent Vivier
2025-04-03 4:54 ` David Gibson
2025-04-02 17:23 ` [PATCH 05/18] packet: Add packet_base() Laurent Vivier
2025-04-03 4:59 ` David Gibson
2025-04-02 17:23 ` [PATCH 06/18] arp: Convert to iov_tail Laurent Vivier
2025-04-03 5:00 ` David Gibson
2025-04-02 17:23 ` [PATCH 07/18] ndp: " Laurent Vivier
2025-04-03 5:01 ` David Gibson
2025-04-02 17:23 ` [PATCH 08/18] icmp: " Laurent Vivier
2025-04-03 5:04 ` David Gibson
2025-04-02 17:23 ` [PATCH 09/18] udp: " Laurent Vivier
2025-04-03 5:11 ` David Gibson
2025-04-02 17:23 ` [PATCH 10/18] tcp: Convert tcp_tap_handler() to use iov_tail Laurent Vivier
2025-04-03 5:14 ` David Gibson
2025-04-02 17:23 ` [PATCH 11/18] tcp: Convert tcp_data_from_tap() " Laurent Vivier
2025-04-03 5:20 ` David Gibson
2025-04-02 17:23 ` [PATCH 12/18] dhcpv6: Convert to iov_tail Laurent Vivier
2025-04-03 5:21 ` David Gibson
2025-04-02 17:23 ` [PATCH 13/18] dhcpv6: move offset initialization out of dhcpv6_opt() Laurent Vivier
2025-04-03 5:25 ` David Gibson
2025-04-02 17:23 ` [PATCH 14/18] dhcpv6: Use iov_tail in dhcpv6_opt() Laurent Vivier
2025-04-03 5:37 ` David Gibson
2025-04-02 17:23 ` [PATCH 15/18] dhcp: Convert to iov_tail Laurent Vivier
2025-04-03 5:47 ` David Gibson
2025-04-02 17:23 ` [PATCH 16/18] tap: " Laurent Vivier
2025-04-02 17:23 ` [PATCH 17/18] ip: Use iov_tail in ipv6_l4hdr() Laurent Vivier
2025-04-02 17:23 ` [PATCH 18/18] tap: Convert to iov_tail Laurent Vivier
Code repositories for project(s) associated with this public inbox
https://passt.top/passt
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for IMAP folder(s).