From 2c3682f0be97a5f57c6c8b40fa154dfc77efb461 Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Sun, 18 Mar 2018 12:56:49 -0700 Subject: sock: make static tls function alloc_sg generic sock helper The TLS ULP module builds scatterlists from a sock using page_frag_refill(). This is going to be useful for other ULPs so move it into sock file for more general use. In the process remove useless goto at end of while loop. Signed-off-by: John Fastabend Acked-by: David S. Miller Signed-off-by: Daniel Borkmann --- net/core/sock.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) (limited to 'net/core/sock.c') diff --git a/net/core/sock.c b/net/core/sock.c index 27f218bba43f..f68dff0d7bc4 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2239,6 +2239,62 @@ bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) } EXPORT_SYMBOL(sk_page_frag_refill); +int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg, + int *sg_num_elem, unsigned int *sg_size, + int first_coalesce) +{ + struct page_frag *pfrag; + unsigned int size = *sg_size; + int num_elem = *sg_num_elem, use = 0, rc = 0; + struct scatterlist *sge; + unsigned int orig_offset; + + len -= size; + pfrag = sk_page_frag(sk); + + while (len > 0) { + if (!sk_page_frag_refill(sk, pfrag)) { + rc = -ENOMEM; + goto out; + } + + use = min_t(int, len, pfrag->size - pfrag->offset); + + if (!sk_wmem_schedule(sk, use)) { + rc = -ENOMEM; + goto out; + } + + sk_mem_charge(sk, use); + size += use; + orig_offset = pfrag->offset; + pfrag->offset += use; + + sge = sg + num_elem - 1; + if (num_elem > first_coalesce && sg_page(sg) == pfrag->page && + sg->offset + sg->length == orig_offset) { + sg->length += use; + } else { + sge++; + sg_unmark_end(sge); + sg_set_page(sge, pfrag->page, use, orig_offset); + get_page(pfrag->page); + ++num_elem; + if (num_elem == MAX_SKB_FRAGS) { + rc = -ENOSPC; + break; + } + } + + len -= use; + } +out: + *sg_size = size; + *sg_num_elem = num_elem; + return rc; +} +EXPORT_SYMBOL(sk_alloc_sg); + static void __lock_sock(struct sock *sk) __releases(&sk->sk_lock.slock) __acquires(&sk->sk_lock.slock) -- cgit v1.2.3-59-g8ed1b From 8c05dbf04b2882c3c0bc43fe7668c720210877f3 Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Sun, 18 Mar 2018 12:57:05 -0700 Subject: net: generalize sk_alloc_sg to work with scatterlist rings The current implementation of sk_alloc_sg expects scatterlist to always start at entry 0 and complete at entry MAX_SKB_FRAGS. Future patches will want to support starting at arbitrary offset into scatterlist so add an additional sg_start parameters and then default to the current values in TLS code paths. Signed-off-by: John Fastabend Acked-by: David S. Miller Signed-off-by: Daniel Borkmann --- include/net/sock.h | 2 +- net/core/sock.c | 27 ++++++++++++++++----------- net/tls/tls_sw.c | 4 ++-- 3 files changed, 19 insertions(+), 14 deletions(-) (limited to 'net/core/sock.c') diff --git a/include/net/sock.h b/include/net/sock.h index 447150c51feb..b7c75e024e37 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2142,7 +2142,7 @@ static inline struct page_frag *sk_page_frag(struct sock *sk) bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg, - int *sg_num_elem, unsigned int *sg_size, + int sg_start, int *sg_curr, unsigned int *sg_size, int first_coalesce); /* diff --git a/net/core/sock.c b/net/core/sock.c index f68dff0d7bc4..4f92c2910200 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2240,19 +2240,20 @@ bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) EXPORT_SYMBOL(sk_page_frag_refill); int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg, - int *sg_num_elem, unsigned int *sg_size, + int sg_start, int *sg_curr_index, unsigned int *sg_curr_size, int first_coalesce) { + int sg_curr = *sg_curr_index, use = 0, rc = 0; + unsigned int size = *sg_curr_size; struct page_frag *pfrag; - unsigned int size = *sg_size; - int num_elem = *sg_num_elem, use = 0, rc = 0; struct scatterlist *sge; - unsigned int orig_offset; len -= size; pfrag = sk_page_frag(sk); while (len > 0) { + unsigned int orig_offset; + if (!sk_page_frag_refill(sk, pfrag)) { rc = -ENOMEM; goto out; @@ -2270,17 +2271,21 @@ int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg, orig_offset = pfrag->offset; pfrag->offset += use; - sge = sg + num_elem - 1; - if (num_elem > first_coalesce && sg_page(sg) == pfrag->page && + sge = sg + sg_curr - 1; + if (sg_curr > first_coalesce && sg_page(sg) == pfrag->page && sg->offset + sg->length == orig_offset) { sg->length += use; } else { - sge++; + sge = sg + sg_curr; sg_unmark_end(sge); sg_set_page(sge, pfrag->page, use, orig_offset); get_page(pfrag->page); - ++num_elem; - if (num_elem == MAX_SKB_FRAGS) { + sg_curr++; + + if (sg_curr == MAX_SKB_FRAGS) + sg_curr = 0; + + if (sg_curr == sg_start) { rc = -ENOSPC; break; } @@ -2289,8 +2294,8 @@ int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg, len -= use; } out: - *sg_size = size; - *sg_num_elem = num_elem; + *sg_curr_size = size; + *sg_curr_index = sg_curr; return rc; } EXPORT_SYMBOL(sk_alloc_sg); diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 0fc8a24c6473..057a558ed6d7 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -94,7 +94,7 @@ static int alloc_encrypted_sg(struct sock *sk, int len) int rc = 0; rc = sk_alloc_sg(sk, len, - ctx->sg_encrypted_data, + ctx->sg_encrypted_data, 0, &ctx->sg_encrypted_num_elem, &ctx->sg_encrypted_size, 0); @@ -107,7 +107,7 @@ static int alloc_plaintext_sg(struct sock *sk, int len) struct tls_sw_context *ctx = tls_sw_ctx(tls_ctx); int rc = 0; - rc = sk_alloc_sg(sk, len, ctx->sg_plaintext_data, + rc = sk_alloc_sg(sk, len, ctx->sg_plaintext_data, 0, &ctx->sg_plaintext_num_elem, &ctx->sg_plaintext_size, tls_ctx->pending_open_record_frags); -- cgit v1.2.3-59-g8ed1b