From 3a261fdeb62a14823b8ff42c3dea8439de30befe Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Tue, 2 Sep 2025 09:52:46 +0200 Subject: dhcp: use iov_tail rather than pool This patch refactors the dhcp() function to accept `struct iov_tail *data` directly as its packet input, replacing the previous `const struct pool *p` parameter. Consequently, dhcp() no longer fetches packet data internally using packet_data(). This change simplifies callers, such as tap4_handler(), which now pass the iov_tail representing the L2 frame directly to dhcp(). This removes the need for intermediate packet pool handling for DHCP processing. Signed-off-by: Laurent Vivier Reviewed-by: David Gibson Signed-off-by: Stefano Brivio --- dhcp.c | 32 ++++++++++++++------------------ dhcp.h | 2 +- tap.c | 5 +---- 3 files changed, 16 insertions(+), 23 deletions(-) diff --git a/dhcp.c b/dhcp.c index 8117529..012cec6 100644 --- a/dhcp.c +++ b/dhcp.c @@ -296,11 +296,11 @@ static void opt_set_dns_search(const struct ctx *c, size_t max_len) /** * dhcp() - Check if this is a DHCP message, reply as needed * @c: Execution context - * @p: Packet pool, single packet with Ethernet buffer + * @data: Single packet with Ethernet buffer * * Return: 0 if it's not a DHCP message, 1 if handled, -1 on failure */ -int dhcp(const struct ctx *c, const struct pool *p) +int dhcp(const struct ctx *c, struct iov_tail *data) { char macstr[ETH_ADDRSTRLEN]; size_t mlen, dlen, opt_len; @@ -311,24 +311,20 @@ int dhcp(const struct ctx *c, const struct pool *p) const struct ethhdr *eh; const struct iphdr *iph; const struct udphdr *uh; - struct iov_tail data; struct msg const *m; struct msg reply; unsigned int i; struct msg m_storage; - if (!packet_get(p, 0, &data)) - return -1; - - eh = IOV_REMOVE_HEADER(&data, eh_storage); - iph = IOV_PEEK_HEADER(&data, iph_storage); + eh = IOV_REMOVE_HEADER(data, eh_storage); + iph = IOV_PEEK_HEADER(data, iph_storage); if (!eh || !iph) return -1; - if (!iov_drop_header(&data, iph->ihl * 4UL)) + if (!iov_drop_header(data, iph->ihl * 4UL)) return -1; - uh = IOV_REMOVE_HEADER(&data, uh_storage); + uh = IOV_REMOVE_HEADER(data, uh_storage); if (!uh) return -1; @@ -338,8 +334,8 @@ int dhcp(const struct ctx *c, const struct pool *p) if (c->no_dhcp) return 1; - mlen = iov_tail_size(&data); - m = (struct msg const *)iov_remove_header_(&data, &m_storage, + mlen = iov_tail_size(data); + m = (struct msg const *)iov_remove_header_(data, &m_storage, offsetof(struct msg, o), __alignof__(struct msg)); if (!m || @@ -367,24 +363,24 @@ int dhcp(const struct ctx *c, const struct pool *p) for (i = 0; i < ARRAY_SIZE(opts); i++) opts[i].clen = -1; - opt_len = iov_tail_size(&data); + opt_len = iov_tail_size(data); while (opt_len >= 2) { uint8_t olen_storage, type_storage; const uint8_t *olen; uint8_t *type; - type = IOV_REMOVE_HEADER(&data, type_storage); - olen = IOV_REMOVE_HEADER(&data, olen_storage); + type = IOV_REMOVE_HEADER(data, type_storage); + olen = IOV_REMOVE_HEADER(data, olen_storage); if (!type || !olen) return -1; - opt_len = iov_tail_size(&data); + opt_len = iov_tail_size(data); if (opt_len < *olen) return -1; - iov_to_buf(&data.iov[0], data.cnt, data.off, &opts[*type].c, *olen); + iov_to_buf(&data->iov[0], data->cnt, data->off, &opts[*type].c, *olen); opts[*type].clen = *olen; - iov_drop_header(&data, *olen); + iov_drop_header(data, *olen); opt_len -= *olen; } diff --git a/dhcp.h b/dhcp.h index 87aeecd..cd50c99 100644 --- a/dhcp.h +++ b/dhcp.h @@ -6,7 +6,7 @@ #ifndef DHCP_H #define DHCP_H -int dhcp(const struct ctx *c, const struct pool *p); +int dhcp(const struct ctx *c, struct iov_tail *data); void dhcp_init(void); #endif /* DHCP_H */ diff --git a/tap.c b/tap.c index 7a538b2..14050b3 100644 --- a/tap.c +++ b/tap.c @@ -785,11 +785,8 @@ resume: if (iph->protocol == IPPROTO_UDP) { struct iov_tail eh_data; - PACKET_POOL_P(pkt, 1, in->buf, in->buf_size); - packet_get(in, i, &eh_data); - packet_add(pkt, &eh_data); - if (dhcp(c, pkt)) + if (dhcp(c, &eh_data)) continue; } -- cgit v1.2.3