March 2026 - dev

[PATCH v3] iov: Add iov_truncate() helper and use it in vu handlers
by Laurent Vivier 06 Mar '26

06 Mar '26

Add a generic iov_truncate() function that truncates an IO vector to a given number of bytes, returning the number of iov entries that contain data after truncation. Use it in udp_vu_sock_recv() and tcp_vu_sock_recv() to replace the open-coded truncation logic that adjusted iov entries after recvmsg(). Also convert the direct iov_len assignment in tcp_vu_send_flag() to use iov_truncate() for consistency. Signed-off-by: Laurent Vivier <lvivier(a)redhat.com> --- Notes: v3: use in tcp_vu_send_flag() too v2: use iov_truncate() in udp_vu_sock_recv() too iov.c | 22 ++++++++++++++++++++++ iov.h | 1 + tcp_vu.c | 14 +++----------- udp_vu.c | 12 +++--------- 4 files changed, 29 insertions(+), 20 deletions(-) diff --git a/iov.c b/iov.c index ad726daa4cd8..31a3f5bc29e5 100644 --- a/iov.c +++ b/iov.c @@ -147,6 +147,28 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt) return len; } +/** + * iov_truncate() - Truncate an IO vector to a given number of bytes + * @iov: IO vector (modified) + * @iov_cnt: Number of entries in @iov + * @size: Total number of bytes to keep + * + * Return: number of iov entries that contain data after truncation + */ +size_t iov_truncate(struct iovec *iov, size_t iov_cnt, size_t size) +{ + size_t i, offset; + + i = iov_skip_bytes(iov, iov_cnt, size, &offset); + + if (i < iov_cnt) { + iov[i].iov_len = offset; + i += !!offset; + } + + return i; +} + /** * iov_tail_prune() - Remove any unneeded buffers from an IOV tail * @tail: IO vector tail (modified) diff --git a/iov.h b/iov.h index d1ab91a94e22..b4e50b0fca5a 100644 --- a/iov.h +++ b/iov.h @@ -29,6 +29,7 @@ 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); +size_t iov_truncate(struct iovec *iov, size_t iov_cnt, size_t size); /* * DOC: Theory of Operation, struct iov_tail diff --git a/tcp_vu.c b/tcp_vu.c index 88be232dca66..8ca4170f13f6 100644 --- a/tcp_vu.c +++ b/tcp_vu.c @@ -131,7 +131,7 @@ int tcp_vu_send_flag(const struct ctx *c, struct tcp_tap_conn *conn, int flags) return ret; } - flags_elem[0].in_sg[0].iov_len = hdrlen + optlen; + iov_truncate(&flags_iov[0], 1, hdrlen + optlen); payload = IOV_TAIL(flags_elem[0].in_sg, 1, hdrlen); if (flags & KEEPALIVE) @@ -192,9 +192,9 @@ static ssize_t tcp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, struct msghdr mh_sock = { 0 }; uint16_t mss = MSS_GET(conn); int s = conn->sock; - ssize_t ret, len; size_t hdrlen; int elem_cnt; + ssize_t ret; int i; *iov_cnt = 0; @@ -247,15 +247,7 @@ static ssize_t tcp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, ret -= already_sent; /* adjust iov number and length of the last iov */ - len = ret; - for (i = 0; len && i < elem_cnt; i++) { - struct iovec *iov = &elem[i].in_sg[0]; - - if (iov->iov_len > (size_t)len) - iov->iov_len = len; - - len -= iov->iov_len; - } + i = iov_truncate(&iov_vu[DISCARD_IOV_NUM], elem_cnt, ret); /* adjust head count */ while (*head_cnt > 0 && head[*head_cnt - 1] >= i) diff --git a/udp_vu.c b/udp_vu.c index 3520f89e5671..5effca777e0a 100644 --- a/udp_vu.c +++ b/udp_vu.c @@ -71,9 +71,9 @@ static int udp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, int s, bool v6, ssize_t *dlen) { const struct vu_dev *vdev = c->vdev; - int iov_cnt, idx, iov_used; - size_t off, hdrlen, l2len; struct msghdr msg = { 0 }; + int iov_cnt, iov_used; + size_t hdrlen, l2len; ASSERT(!c->no_udp); @@ -115,13 +115,7 @@ static int udp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, int s, iov_vu[0].iov_base = (char *)iov_vu[0].iov_base - hdrlen; iov_vu[0].iov_len += hdrlen; - /* count the numbers of buffer filled by recvmsg() */ - idx = iov_skip_bytes(iov_vu, iov_cnt, *dlen + hdrlen, &off); - - /* adjust last iov length */ - if (idx < iov_cnt) - iov_vu[idx].iov_len = off; - iov_used = idx + !!off; + iov_used = iov_truncate(iov_vu, iov_cnt, *dlen + hdrlen); /* pad frame to 60 bytes: first buffer is at least ETH_ZLEN long */ l2len = *dlen + hdrlen - VNET_HLEN; -- 2.53.0

3 9

[PATCH v2] iov: Add iov_truncate() helper and use it in vu handlers
by Laurent Vivier 05 Mar '26

05 Mar '26

Add a generic iov_truncate() function that truncates an IO vector to a given number of bytes, returning the number of iov entries that contain data after truncation. Use it in udp_vu_sock_recv() and tcp_vu_sock_recv() to replace the open-coded truncation logic that adjusted iov entries after recvmsg(). Signed-off-by: Laurent Vivier <lvivier(a)redhat.com> --- Notes: v2: use iov_truncate() in udp_vu_sock_recv() too iov.c | 22 ++++++++++++++++++++++ iov.h | 1 + tcp_vu.c | 12 ++---------- udp_vu.c | 12 +++--------- 4 files changed, 28 insertions(+), 19 deletions(-) diff --git a/iov.c b/iov.c index ad726daa4cd8..31a3f5bc29e5 100644 --- a/iov.c +++ b/iov.c @@ -147,6 +147,28 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt) return len; } +/** + * iov_truncate() - Truncate an IO vector to a given number of bytes + * @iov: IO vector (modified) + * @iov_cnt: Number of entries in @iov + * @size: Total number of bytes to keep + * + * Return: number of iov entries that contain data after truncation + */ +size_t iov_truncate(struct iovec *iov, size_t iov_cnt, size_t size) +{ + size_t i, offset; + + i = iov_skip_bytes(iov, iov_cnt, size, &offset); + + if (i < iov_cnt) { + iov[i].iov_len = offset; + i += !!offset; + } + + return i; +} + /** * iov_tail_prune() - Remove any unneeded buffers from an IOV tail * @tail: IO vector tail (modified) diff --git a/iov.h b/iov.h index d1ab91a94e22..b4e50b0fca5a 100644 --- a/iov.h +++ b/iov.h @@ -29,6 +29,7 @@ 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); +size_t iov_truncate(struct iovec *iov, size_t iov_cnt, size_t size); /* * DOC: Theory of Operation, struct iov_tail diff --git a/tcp_vu.c b/tcp_vu.c index 88be232dca66..15405a26c7c3 100644 --- a/tcp_vu.c +++ b/tcp_vu.c @@ -192,9 +192,9 @@ static ssize_t tcp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, struct msghdr mh_sock = { 0 }; uint16_t mss = MSS_GET(conn); int s = conn->sock; - ssize_t ret, len; size_t hdrlen; int elem_cnt; + ssize_t ret; int i; *iov_cnt = 0; @@ -247,15 +247,7 @@ static ssize_t tcp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, ret -= already_sent; /* adjust iov number and length of the last iov */ - len = ret; - for (i = 0; len && i < elem_cnt; i++) { - struct iovec *iov = &elem[i].in_sg[0]; - - if (iov->iov_len > (size_t)len) - iov->iov_len = len; - - len -= iov->iov_len; - } + i = iov_truncate(&iov_vu[DISCARD_IOV_NUM], elem_cnt, ret); /* adjust head count */ while (*head_cnt > 0 && head[*head_cnt - 1] >= i) diff --git a/udp_vu.c b/udp_vu.c index 3520f89e5671..5effca777e0a 100644 --- a/udp_vu.c +++ b/udp_vu.c @@ -71,9 +71,9 @@ static int udp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, int s, bool v6, ssize_t *dlen) { const struct vu_dev *vdev = c->vdev; - int iov_cnt, idx, iov_used; - size_t off, hdrlen, l2len; struct msghdr msg = { 0 }; + int iov_cnt, iov_used; + size_t hdrlen, l2len; ASSERT(!c->no_udp); @@ -115,13 +115,7 @@ static int udp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, int s, iov_vu[0].iov_base = (char *)iov_vu[0].iov_base - hdrlen; iov_vu[0].iov_len += hdrlen; - /* count the numbers of buffer filled by recvmsg() */ - idx = iov_skip_bytes(iov_vu, iov_cnt, *dlen + hdrlen, &off); - - /* adjust last iov length */ - if (idx < iov_cnt) - iov_vu[idx].iov_len = off; - iov_used = idx + !!off; + iov_used = iov_truncate(iov_vu, iov_cnt, *dlen + hdrlen); /* pad frame to 60 bytes: first buffer is at least ETH_ZLEN long */ l2len = *dlen + hdrlen - VNET_HLEN; -- 2.53.0

1 0

[PATCH] tcp: Avoid comparison of expressions with different signedness in tcp_timer_handler()
by Stefano Brivio 05 Mar '26

05 Mar '26

With gcc 14.2, building against musl 1.2.5 (slightly outdated Alpine on x86_64): tcp.c: In function 'tcp_timer_handler': util.h:40:39: warning: comparison of integer expressions of different signedness: 'unsigned int' and 'int' [-Wsign-compare] 40 | #define MIN(x, y) (((x) < (y)) ? (x) : (y)) | ^ tcp.c:2593:31: note: in expansion of macro 'MIN' 2593 | max = MIN(TCP_MAX_RETRIES, max); | ^~~ util.h:40:54: warning: operand of '?:' changes signedness from 'int' to 'unsigned int' due to unsignedness of other operand [-Wsign-compare] 40 | #define MIN(x, y) (((x) < (y)) ? (x) : (y)) | ^~~ tcp.c:2593:31: note: in expansion of macro 'MIN' 2593 | max = MIN(TCP_MAX_RETRIES, max); | ^~~ for some reason, that's not reported by gcc with glibc. Make the temporary 'max' variable unsigned, as we know it can't be negative anyway. While at it, add the customary blank line between variable declarations and code. Fixes: 3dde0e07804e ("tcp: Update data retransmission timeout") Signed-off-by: Stefano Brivio <sbrivio(a)redhat.com> --- tcp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tcp.c b/tcp.c index 88ad886..68c92da 100644 --- a/tcp.c +++ b/tcp.c @@ -2588,7 +2588,8 @@ void tcp_timer_handler(const struct ctx *c, union epoll_ref ref) tcp_timer_ctl(c, conn); } else if (conn->flags & ACK_FROM_TAP_DUE) { if (!(conn->events & ESTABLISHED)) { - int max; + unsigned int max; + max = c->tcp.syn_retries + c->tcp.syn_linear_timeouts; max = MIN(TCP_MAX_RETRIES, max); if (conn->retries >= max) { -- 2.43.0

2 1

[PATCH] migrate: Rename v1 address functions to v2 for clarity
by Jon Maloy 05 Mar '26

05 Mar '26

Some migration address structures and functions have a _v1 suffix. This is confusing, since they are currently handling version 2 of the migration protocol. We are soon going to introduce a new version 3 of the protocol, so we choose to give these functions the correct suffix _v2 instead. This is in correspondence with current reality, and will help make a clearer distinction between the old and the new versions of those functions. Signed-off-by: Jon Maloy <jmaloy(a)redhat.com> Reviewed-by: David Gibson <david(a)gibson.dropbear.id.au> --- migrate.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/migrate.c b/migrate.c index 13bacab..1e8858a 100644 --- a/migrate.c +++ b/migrate.c @@ -29,13 +29,13 @@ #define MIGRATE_MAGIC 0xB1BB1D1B0BB1D1B0 /** - * struct migrate_seen_addrs_v1 - Migratable guest addresses for v1 state stream + * struct migrate_seen_addrs_v2 - Migratable guest addresses for v2 state stream * @addr6: Observed guest IPv6 address * @addr6_ll: Observed guest IPv6 link-local address * @addr4: Observed guest IPv4 address * @mac: Observed guest MAC address */ -struct migrate_seen_addrs_v1 { +struct migrate_seen_addrs_v2 { struct in6_addr addr6; struct in6_addr addr6_ll; struct in_addr addr4; @@ -43,7 +43,7 @@ struct migrate_seen_addrs_v1 { } __attribute__((packed)); /** - * seen_addrs_source_v1() - Copy and send guest observed addresses from source + * seen_addrs_source_v2() - Copy and send guest observed addresses from source * @c: Execution context * @stage: Migration stage, unused * @fd: File descriptor for state transfer @@ -51,10 +51,10 @@ struct migrate_seen_addrs_v1 { * Return: 0 on success, positive error code on failure */ /* cppcheck-suppress [constParameterCallback, unmatchedSuppression] */ -static int seen_addrs_source_v1(struct ctx *c, +static int seen_addrs_source_v2(struct ctx *c, const struct migrate_stage *stage, int fd) { - struct migrate_seen_addrs_v1 addrs = { + struct migrate_seen_addrs_v2 addrs = { .addr6 = c->ip6.addr_seen, .addr6_ll = c->ip6.addr_ll_seen, .addr4 = c->ip4.addr_seen, @@ -71,17 +71,17 @@ static int seen_addrs_source_v1(struct ctx *c, } /** - * seen_addrs_target_v1() - Receive and use guest observed addresses on target + * seen_addrs_target_v2() - Receive and use guest observed addresses on target * @c: Execution context * @stage: Migration stage, unused * @fd: File descriptor for state transfer * * Return: 0 on success, positive error code on failure */ -static int seen_addrs_target_v1(struct ctx *c, +static int seen_addrs_target_v2(struct ctx *c, const struct migrate_stage *stage, int fd) { - struct migrate_seen_addrs_v1 addrs; + struct migrate_seen_addrs_v2 addrs; (void)stage; @@ -100,8 +100,8 @@ static int seen_addrs_target_v1(struct ctx *c, static const struct migrate_stage stages_v2[] = { { .name = "observed addresses", - .source = seen_addrs_source_v1, - .target = seen_addrs_target_v1, + .source = seen_addrs_source_v2, + .target = seen_addrs_target_v2, }, { .name = "prepare flows", -- 2.52.0

3 2

[PATCH] vu_common: Always set num_buffers in virtio-net header
by Laurent Vivier 05 Mar '26

05 Mar '26

Legacy virtio used two different header formats: struct virtio_net_hdr (10 bytes) when VIRTIO_NET_F_MRG_RXBUF was not negotiated, and struct virtio_net_hdr_mrg_rxbuf (12 bytes) when it was. The num_buffers field only existed in the larger header. Modern virtio (VIRTIO_F_VERSION_1, i.e. virtio 1.0+) always uses the 12-byte struct virtio_net_hdr_mrg_rxbuf header regardless of whether VIRTIO_NET_F_MRG_RXBUF is negotiated, so num_buffers is always present in the header. passt only supports modern virtio and dies if VIRTIO_F_VERSION_1 is not negotiated (vhost_user.c), and VNET_HLEN is unconditionally defined as sizeof(struct virtio_net_hdr_mrg_rxbuf). The virtio specification (v1.1, section 5.1.6) requires that: "The device MUST set num_buffers to 1 if VIRTIO_NET_F_MRG_RXBUF has not been negotiated." vu_set_vnethdr() only set num_buffers when VIRTIO_NET_F_MRG_RXBUF was negotiated. When it was not, num_buffers was left uninitialised, violating the spec. Since vu_collect() already limits buffer collection to a single element when VIRTIO_NET_F_MRG_RXBUF is not negotiated, num_buffers passed by callers is guaranteed to be 1 in that case. We can therefore unconditionally set num_buffers, which makes the vdev parameter unnecessary. Drop the vdev parameter from vu_set_vnethdr() and update all callers. Signed-off-by: Laurent Vivier <lvivier(a)redhat.com> --- tcp_vu.c | 4 ++-- udp_vu.c | 2 +- vu_common.c | 13 ++++++------- vu_common.h | 4 +--- 4 files changed, 10 insertions(+), 13 deletions(-) diff --git a/tcp_vu.c b/tcp_vu.c index bb05fbf45826..88be232dca66 100644 --- a/tcp_vu.c +++ b/tcp_vu.c @@ -97,7 +97,7 @@ int tcp_vu_send_flag(const struct ctx *c, struct tcp_tap_conn *conn, int flags) ASSERT(flags_elem[0].in_sg[0].iov_len >= MAX(hdrlen + sizeof(*opts), ETH_ZLEN + VNET_HLEN)); - vu_set_vnethdr(vdev, flags_elem[0].in_sg[0].iov_base, 1); + vu_set_vnethdr(flags_elem[0].in_sg[0].iov_base, 1); eh = vu_eth(flags_elem[0].in_sg[0].iov_base); @@ -452,7 +452,7 @@ int tcp_vu_data_from_sock(const struct ctx *c, struct tcp_tap_conn *conn) bool push = i == head_cnt - 1; size_t l2len; - vu_set_vnethdr(vdev, iov->iov_base, buf_cnt); + vu_set_vnethdr(iov->iov_base, buf_cnt); /* The IPv4 header checksum varies only with dlen */ if (previous_dlen != dlen) diff --git a/udp_vu.c b/udp_vu.c index 51f3718f5925..3520f89e5671 100644 --- a/udp_vu.c +++ b/udp_vu.c @@ -127,7 +127,7 @@ static int udp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, int s, l2len = *dlen + hdrlen - VNET_HLEN; vu_pad(&iov_vu[0], l2len); - vu_set_vnethdr(vdev, iov_vu[0].iov_base, iov_used); + vu_set_vnethdr(iov_vu[0].iov_base, iov_used); /* release unused buffers */ vu_queue_rewind(vq, iov_cnt - iov_used); diff --git a/vu_common.c b/vu_common.c index aa14598ea028..5f2ce18e5b71 100644 --- a/vu_common.c +++ b/vu_common.c @@ -121,17 +121,16 @@ int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq, /** * vu_set_vnethdr() - set virtio-net headers - * @vdev: vhost-user device * @vnethdr: Address of the header to set * @num_buffers: Number of guest buffers of the frame */ -void vu_set_vnethdr(const struct vu_dev *vdev, - struct virtio_net_hdr_mrg_rxbuf *vnethdr, - int num_buffers) +void vu_set_vnethdr(struct virtio_net_hdr_mrg_rxbuf *vnethdr, int num_buffers) { vnethdr->hdr = VU_HEADER; - if (vu_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF)) - vnethdr->num_buffers = htole16(num_buffers); + /* Note: if VIRTIO_NET_F_MRG_RXBUF is not negotiated, + * num_buffers must be 1 + */ + vnethdr->num_buffers = htole16(num_buffers); } /** @@ -269,7 +268,7 @@ int vu_send_single(const struct ctx *c, const void *buf, size_t size) goto err; } - vu_set_vnethdr(vdev, in_sg[0].iov_base, elem_cnt); + vu_set_vnethdr(in_sg[0].iov_base, elem_cnt); total -= VNET_HLEN; diff --git a/vu_common.h b/vu_common.h index 052aff710502..20868a7f62ce 100644 --- a/vu_common.h +++ b/vu_common.h @@ -49,9 +49,7 @@ void vu_init_elem(struct vu_virtq_element *elem, struct iovec *iov, int vu_collect(const struct vu_dev *vdev, struct vu_virtq *vq, struct vu_virtq_element *elem, int max_elem, size_t size, size_t *collected); -void vu_set_vnethdr(const struct vu_dev *vdev, - struct virtio_net_hdr_mrg_rxbuf *vnethdr, - int num_buffers); +void vu_set_vnethdr(struct virtio_net_hdr_mrg_rxbuf *vnethdr, int num_buffers); void vu_flush(const struct vu_dev *vdev, struct vu_virtq *vq, struct vu_virtq_element *elem, int elem_cnt); void vu_kick_cb(struct vu_dev *vdev, union epoll_ref ref, -- 2.53.0

3 2

[PATCH 1/3] tcp: Use flow_foreach_of_type() in tcp_{keepalive,inactivity}
by David Gibson 05 Mar '26

05 Mar '26

These functions step through all TCP flows. I forgot there was already a flow_foreach_of_type() macro which makes this easier. Use it. Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au> --- tcp.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/tcp.c b/tcp.c index 88ad886d..16470703 100644 --- a/tcp.c +++ b/tcp.c @@ -2907,12 +2907,9 @@ static void tcp_keepalive(struct ctx *c, const struct timespec *now) c->tcp.keepalive_run = now->tv_sec; - flow_foreach(flow) { + flow_foreach_of_type(flow, FLOW_TCP) { struct tcp_tap_conn *conn = &flow->tcp; - if (flow->f.type != FLOW_TCP) - continue; - if (conn->tap_inactive) { flow_dbg(conn, "No tap activity for least %us, send keepalive", KEEPALIVE_INTERVAL); @@ -2938,12 +2935,9 @@ static void tcp_inactivity(struct ctx *c, const struct timespec *now) debug("TCP inactivity scan"); c->tcp.inactivity_run = now->tv_sec; - flow_foreach(flow) { + flow_foreach_of_type(flow, FLOW_TCP) { struct tcp_tap_conn *conn = &flow->tcp; - if (flow->f.type != FLOW_TCP) - continue; - if (conn->inactive) { /* No activity in this interval, reset */ flow_dbg(conn, "Inactive for at least %us, resetting", -- 2.53.0

2 1

[PATCH 3/3] clang-tidy: Don't insist on #ifdef over #if defined()
by David Gibson 05 Mar '26

05 Mar '26

Commit 036fb8770 ("checksum: add VSX fast path for POWER8/POWER9") changed an #ifdef to #if defined, in order to match a newly introduced #if which needs to check two different symbols. This causes clang-tidy to complain that the directive could be written more concisely. In this case consistency with the other #if branch seems more important, and in general insisting on #ifdef over #if seems unhelpfully pedantic. Suppress that warning globally. Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au> --- .clang-tidy | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/.clang-tidy b/.clang-tidy index 9d346ec2..773121f5 100644 --- a/.clang-tidy +++ b/.clang-tidy @@ -81,6 +81,11 @@ Checks: # precedence over addition in modern mathematical notation. Adding # parentheses to reinforce that certainly won't improve readability. - "-readability-math-missing-parentheses" + + # #if defined(FOO) is fine, and can be more consistent with other + # #if directives. Don't insist on #ifdef instead. + - "-readability-use-concise-preprocessor-directives" + WarningsAsErrors: "*" HeaderFileExtensions: - h -- 2.53.0

2 1

[PATCH 2/3] fwd, pif: Replace with pif_sock_l4() with pif_listen()
by David Gibson 05 Mar '26

05 Mar '26

It turns out all users of pif_sock_l4() use it for "listening" sockets, which now all have a common epoll reference format. We can take advantage of that to pass the necessary epoll information into pif_sock_l4() in a more natural way, rather than as an opaque u32. That in turn allows union fwd_listen_ref can become a struct, since the union only exist to allow the meaningful fields to be coerced into a u32 for pif_sock_l4(). Rename pif_sock_l4() to pif_listen() to reflect the new semantics. While we're there, remove the static_assert() on the fwd_listen_ref's size. We do still need it to fit into 32 bits, but that constraint is imposed only by the fact that it needs to fit into the whole, epoll_ref structure, which we already check with a static_assert() in epoll_ctl.h. Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au> --- epoll_ctl.h | 2 +- fwd.h | 14 +++++--------- pif.c | 14 ++++++++------ pif.h | 6 +++--- tcp.c | 8 +------- udp.c | 8 +------- 6 files changed, 19 insertions(+), 33 deletions(-) diff --git a/epoll_ctl.h b/epoll_ctl.h index 2c103cde..879763cb 100644 --- a/epoll_ctl.h +++ b/epoll_ctl.h @@ -35,7 +35,7 @@ union epoll_ref { union { uint32_t flow; flow_sidx_t flowside; - union fwd_listen_ref listen; + struct fwd_listen_ref listen; uint32_t data; int nsdir_fd; int queue; diff --git a/fwd.h b/fwd.h index 16070111..b0e2373d 100644 --- a/fwd.h +++ b/fwd.h @@ -49,20 +49,16 @@ struct fwd_rule { #define FWD_NO_HINT (-1) /** - * union fwd_listen_ref - information about a single listening socket + * struct fwd_listen_ref - information about a single listening socket * @port: Bound port number of the socket * @pif: pif in which the socket is listening * @rule: Index of forwarding rule */ -union fwd_listen_ref { - struct { - in_port_t port; - uint8_t pif; - unsigned rule :FWD_RULE_BITS; - }; - uint32_t u32; +struct fwd_listen_ref { + in_port_t port; + uint8_t pif; + unsigned rule :FWD_RULE_BITS; }; -static_assert(sizeof(union fwd_listen_ref) == sizeof(uint32_t)); enum fwd_ports_mode { FWD_UNSET = 0, diff --git a/pif.c b/pif.c index 6ae970a0..82a3b5e4 100644 --- a/pif.c +++ b/pif.c @@ -62,23 +62,23 @@ void pif_sockaddr(const struct ctx *c, union sockaddr_inany *sa, } } -/** pif_sock_l4() - Open a socket bound to an address on a specified interface +/** pif_listen() - Open a listening socket on a specified pif * @c: Execution context * @type: Socket epoll type * @pif: Interface for this socket * @addr: Address to bind to, or NULL for dual-stack any * @ifname: Interface for binding, NULL for any * @port: Port number to bind to (host byte order) - * @data: epoll reference portion for protocol handlers + * @rule: Forwarding rule index this socket belongs to * * NOTE: For namespace pifs, this must be called having already entered the * relevant namespace. * * Return: newly created socket, negative error code on failure */ -int pif_sock_l4(const struct ctx *c, enum epoll_type type, uint8_t pif, - const union inany_addr *addr, const char *ifname, - in_port_t port, uint32_t data) +int pif_listen(const struct ctx *c, enum epoll_type type, uint8_t pif, + const union inany_addr *addr, const char *ifname, + in_port_t port, unsigned rule) { union epoll_ref ref; int ret; @@ -98,7 +98,9 @@ int pif_sock_l4(const struct ctx *c, enum epoll_type type, uint8_t pif, return ref.fd; ref.type = type; - ref.data = data; + ref.listen.port = port; + ref.listen.pif = pif; + ref.listen.rule = rule; ret = epoll_add(c->epollfd, EPOLLIN, ref); if (ret < 0) { diff --git a/pif.h b/pif.h index 0f7f6672..0eb3626a 100644 --- a/pif.h +++ b/pif.h @@ -59,8 +59,8 @@ static inline bool pif_is_socket(uint8_t pif) void pif_sockaddr(const struct ctx *c, union sockaddr_inany *sa, uint8_t pif, const union inany_addr *addr, in_port_t port); -int pif_sock_l4(const struct ctx *c, enum epoll_type type, uint8_t pif, - const union inany_addr *addr, const char *ifname, - in_port_t port, uint32_t data); +int pif_listen(const struct ctx *c, enum epoll_type type, uint8_t pif, + const union inany_addr *addr, const char *ifname, + in_port_t port, unsigned rule); #endif /* PIF_H */ diff --git a/tcp.c b/tcp.c index 16470703..a0d7cd86 100644 --- a/tcp.c +++ b/tcp.c @@ -2698,11 +2698,6 @@ void tcp_sock_handler(const struct ctx *c, union epoll_ref ref, int tcp_listen(const struct ctx *c, uint8_t pif, unsigned rule, const union inany_addr *addr, const char *ifname, in_port_t port) { - union fwd_listen_ref ref = { - .port = port, - .pif = pif, - .rule = rule, - }; int s; ASSERT(!c->no_tcp); @@ -2722,8 +2717,7 @@ int tcp_listen(const struct ctx *c, uint8_t pif, unsigned rule, return -EAFNOSUPPORT; } - s = pif_sock_l4(c, EPOLL_TYPE_TCP_LISTEN, pif, addr, ifname, - port, ref.u32); + s = pif_listen(c, EPOLL_TYPE_TCP_LISTEN, pif, addr, ifname, port, rule); return s; } diff --git a/udp.c b/udp.c index 19adda06..464aa093 100644 --- a/udp.c +++ b/udp.c @@ -1139,11 +1139,6 @@ int udp_tap_handler(const struct ctx *c, uint8_t pif, int udp_listen(const struct ctx *c, uint8_t pif, unsigned rule, const union inany_addr *addr, const char *ifname, in_port_t port) { - union fwd_listen_ref ref = { - .pif = pif, - .port = port, - .rule = rule, - }; int s; ASSERT(!c->no_udp); @@ -1163,8 +1158,7 @@ int udp_listen(const struct ctx *c, uint8_t pif, unsigned rule, return -EAFNOSUPPORT; } - s = pif_sock_l4(c, EPOLL_TYPE_UDP_LISTEN, pif, - addr, ifname, port, ref.u32); + s = pif_listen(c, EPOLL_TYPE_UDP_LISTEN, pif, addr, ifname, port, rule); return s; } -- 2.53.0

2 3

[PATCH] Add missing includes to headers
by Peter Foley 05 Mar '26

05 Mar '26

Support build systems like bazel that check that headers are self-contained. Signed-off-by: Peter Foley <pefoley(a)google.com> --- flow.h | 6 ++++++ flow_table.h | 1 + icmp_flow.h | 2 ++ inany.h | 5 +++++ ip.h | 2 ++ linux_dep.h | 3 +++ pif.h | 4 ++++ seccomp.sh | 5 +++++ siphash.h | 3 +++ tap.h | 5 +++++ tcp_conn.h | 4 ++++ tcp_internal.h | 5 +++++ udp_internal.h | 3 +++ util.c | 1 + 14 files changed, 49 insertions(+) diff --git a/flow.h b/flow.h index d636358..897c9ea 100644 --- a/flow.h +++ b/flow.h @@ -7,6 +7,12 @@ #ifndef FLOW_H #define FLOW_H +#include <stdint.h> +#include <netinet/in.h> + +#include "inany.h" +#include "util.h" + #define FLOW_TIMER_INTERVAL 1000 /* ms */ /** diff --git a/flow_table.h b/flow_table.h index 73de13b..8fb7b5c 100644 --- a/flow_table.h +++ b/flow_table.h @@ -7,6 +7,7 @@ #ifndef FLOW_TABLE_H #define FLOW_TABLE_H +#include "pif.h" #include "tcp_conn.h" #include "icmp_flow.h" #include "udp_flow.h" diff --git a/icmp_flow.h b/icmp_flow.h index fb93801..3af98be 100644 --- a/icmp_flow.h +++ b/icmp_flow.h @@ -7,6 +7,8 @@ #ifndef ICMP_FLOW_H #define ICMP_FLOW_H +#include "flow.h" + /** * struct icmp_ping_flow - Descriptor for a flow of ping requests/replies * @f: Generic flow information diff --git a/inany.h b/inany.h index b02c289..c7de094 100644 --- a/inany.h +++ b/inany.h @@ -9,6 +9,11 @@ #ifndef INANY_H #define INANY_H +#include <string.h> + +#include "ip.h" +#include "siphash.h" + struct siphash_state; /** union inany_addr - Represents either an IPv4 or IPv6 address diff --git a/ip.h b/ip.h index a8043c2..3be2d4e 100644 --- a/ip.h +++ b/ip.h @@ -9,6 +9,8 @@ #include <netinet/ip.h> #include <netinet/ip6.h> +#include "util.h" + #define IN4_IS_ADDR_UNSPECIFIED(a) \ (((struct in_addr *)(a))->s_addr == htonl_constant(INADDR_ANY)) #define IN4_IS_ADDR_BROADCAST(a) \ diff --git a/linux_dep.h b/linux_dep.h index 89e590c..3f8184b 100644 --- a/linux_dep.h +++ b/linux_dep.h @@ -7,6 +7,9 @@ #ifndef LINUX_DEP_H #define LINUX_DEP_H +#include <stdint.h> +#include <unistd.h> + /* struct tcp_info_linux - Information from Linux TCP_INFO getsockopt() * * Largely derived from include/linux/tcp.h in the Linux kernel diff --git a/pif.h b/pif.h index 0f7f667..7c755bd 100644 --- a/pif.h +++ b/pif.h @@ -7,6 +7,10 @@ #ifndef PIF_H #define PIF_H +#include <netinet/in.h> + +#include "epoll_type.h" + union inany_addr; union sockaddr_inany; diff --git a/seccomp.sh b/seccomp.sh index 60ebe84..5347586 100755 --- a/seccomp.sh +++ b/seccomp.sh @@ -34,6 +34,11 @@ AUDIT_ARCH="AUDIT_ARCH_$(echo ${ARCH} | tr '[a-z]' '[A-Z]' \ HEADER="/* This file was automatically generated by $(basename ${0}) */ +#include <stddef.h> +#include <linux/audit.h> +#include <linux/filter.h> +#include <linux/seccomp.h> + #ifndef AUDIT_ARCH_PPC64LE #define AUDIT_ARCH_PPC64LE (AUDIT_ARCH_PPC64 | __AUDIT_ARCH_LE) #endif" diff --git a/siphash.h b/siphash.h index e760236..bbddcac 100644 --- a/siphash.h +++ b/siphash.h @@ -44,6 +44,9 @@ #ifndef SIPHASH_H #define SIPHASH_H +#include <stddef.h> +#include <stdint.h> + /** * struct siphash_state - Internal state of siphash calculation */ diff --git a/tap.h b/tap.h index cc780d1..07ca096 100644 --- a/tap.h +++ b/tap.h @@ -6,6 +6,11 @@ #ifndef TAP_H #define TAP_H +#include <stddef.h> +#include <stdint.h> + +#include "passt.h" + /** L2_MAX_LEN_PASTA - Maximum frame length for pasta mode (with L2 header) * * The kernel tuntap device imposes a maximum frame size of 65535 including diff --git a/tcp_conn.h b/tcp_conn.h index 21cea10..d4d0139 100644 --- a/tcp_conn.h +++ b/tcp_conn.h @@ -9,6 +9,10 @@ #ifndef TCP_CONN_H #define TCP_CONN_H +#include <stdint.h> + +#include "flow.h" + /** * struct tcp_tap_conn - Descriptor for a TCP connection (not spliced) * @f: Generic flow information diff --git a/tcp_internal.h b/tcp_internal.h index 518913b..591e58c 100644 --- a/tcp_internal.h +++ b/tcp_internal.h @@ -6,6 +6,11 @@ #ifndef TCP_INTERNAL_H #define TCP_INTERNAL_H +#include <stdint.h> +#include <netinet/tcp.h> + +#include "util.h" + #define MAX_WS 8 #define MAX_WINDOW (1 << (16 + (MAX_WS))) diff --git a/udp_internal.h b/udp_internal.h index 0a8fe49..64e4577 100644 --- a/udp_internal.h +++ b/udp_internal.h @@ -6,6 +6,9 @@ #ifndef UDP_INTERNAL_H #define UDP_INTERNAL_H +#include <netinet/in.h> +#include <netinet/udp.h> + #include "tap.h" /* needed by udp_meta_t */ /** diff --git a/util.c b/util.c index a48f727..db27431 100644 --- a/util.c +++ b/util.c @@ -25,6 +25,7 @@ #include <errno.h> #include <stdbool.h> #include <linux/errqueue.h> +#include <linux/in6.h> #include <getopt.h> #include "linux_dep.h" -- 2.53.0.371.g1d285c8824-goog

3 25

[PATCH] iov: Add iov_truncate() helper and use it in udp_vu_sock_recv()
by Laurent Vivier 04 Mar '26

04 Mar '26

Add a generic iov_truncate() function that truncates an IO vector to a given number of bytes, returning the number of iov entries that contain data after truncation. Use it in udp_vu_sock_recv() to replace the open-coded truncation logic that adjusted iov entries after recvmsg(). Signed-off-by: Laurent Vivier <lvivier(a)redhat.com> --- iov.c | 22 ++++++++++++++++++++++ iov.h | 1 + udp_vu.c | 12 +++--------- 3 files changed, 26 insertions(+), 9 deletions(-) diff --git a/iov.c b/iov.c index ad726daa4cd8..31a3f5bc29e5 100644 --- a/iov.c +++ b/iov.c @@ -147,6 +147,28 @@ size_t iov_size(const struct iovec *iov, size_t iov_cnt) return len; } +/** + * iov_truncate() - Truncate an IO vector to a given number of bytes + * @iov: IO vector (modified) + * @iov_cnt: Number of entries in @iov + * @size: Total number of bytes to keep + * + * Return: number of iov entries that contain data after truncation + */ +size_t iov_truncate(struct iovec *iov, size_t iov_cnt, size_t size) +{ + size_t i, offset; + + i = iov_skip_bytes(iov, iov_cnt, size, &offset); + + if (i < iov_cnt) { + iov[i].iov_len = offset; + i += !!offset; + } + + return i; +} + /** * iov_tail_prune() - Remove any unneeded buffers from an IOV tail * @tail: IO vector tail (modified) diff --git a/iov.h b/iov.h index d2184bfd12bd..f87436f5479b 100644 --- a/iov.h +++ b/iov.h @@ -28,6 +28,7 @@ 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); +size_t iov_truncate(struct iovec *iov, size_t iov_cnt, size_t size); /* * DOC: Theory of Operation, struct iov_tail diff --git a/udp_vu.c b/udp_vu.c index 51f3718f5925..3f558a33b4f2 100644 --- a/udp_vu.c +++ b/udp_vu.c @@ -71,9 +71,9 @@ static int udp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, int s, bool v6, ssize_t *dlen) { const struct vu_dev *vdev = c->vdev; - int iov_cnt, idx, iov_used; - size_t off, hdrlen, l2len; struct msghdr msg = { 0 }; + int iov_cnt, iov_used; + size_t hdrlen, l2len; ASSERT(!c->no_udp); @@ -115,13 +115,7 @@ static int udp_vu_sock_recv(const struct ctx *c, struct vu_virtq *vq, int s, iov_vu[0].iov_base = (char *)iov_vu[0].iov_base - hdrlen; iov_vu[0].iov_len += hdrlen; - /* count the numbers of buffer filled by recvmsg() */ - idx = iov_skip_bytes(iov_vu, iov_cnt, *dlen + hdrlen, &off); - - /* adjust last iov length */ - if (idx < iov_cnt) - iov_vu[idx].iov_len = off; - iov_used = idx + !!off; + iov_used = iov_truncate(iov_vu, iov_cnt, *dlen + hdrlen); /* pad frame to 60 bytes: first buffer is at least ETH_ZLEN long */ l2len = *dlen + hdrlen - VNET_HLEN; -- 2.53.0

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