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Diffstat (limited to 'net/core/skbuff.c')
-rw-r--r--net/core/skbuff.c308
1 files changed, 122 insertions, 186 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index cea28d30abb5..6c5915efbc17 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -67,6 +67,7 @@
#include <net/dst.h>
#include <net/sock.h>
#include <net/checksum.h>
+#include <net/gso.h>
#include <net/ip6_checksum.h>
#include <net/xfrm.h>
#include <net/mpls.h>
@@ -92,15 +93,7 @@ static struct kmem_cache *skbuff_fclone_cache __ro_after_init;
static struct kmem_cache *skbuff_ext_cache __ro_after_init;
#endif
-/* skb_small_head_cache and related code is only supported
- * for CONFIG_SLAB and CONFIG_SLUB.
- * As soon as SLOB is removed from the kernel, we can clean up this.
- */
-#if !defined(CONFIG_SLOB)
-# define HAVE_SKB_SMALL_HEAD_CACHE 1
-#endif
-#ifdef HAVE_SKB_SMALL_HEAD_CACHE
static struct kmem_cache *skb_small_head_cache __ro_after_init;
#define SKB_SMALL_HEAD_SIZE SKB_HEAD_ALIGN(MAX_TCP_HEADER)
@@ -117,7 +110,6 @@ static struct kmem_cache *skb_small_head_cache __ro_after_init;
#define SKB_SMALL_HEAD_HEADROOM \
SKB_WITH_OVERHEAD(SKB_SMALL_HEAD_CACHE_SIZE)
-#endif /* HAVE_SKB_SMALL_HEAD_CACHE */
int sysctl_max_skb_frags __read_mostly = MAX_SKB_FRAGS;
EXPORT_SYMBOL(sysctl_max_skb_frags);
@@ -562,7 +554,6 @@ static void *kmalloc_reserve(unsigned int *size, gfp_t flags, int node,
void *obj;
obj_size = SKB_HEAD_ALIGN(*size);
-#ifdef HAVE_SKB_SMALL_HEAD_CACHE
if (obj_size <= SKB_SMALL_HEAD_CACHE_SIZE &&
!(flags & KMALLOC_NOT_NORMAL_BITS)) {
obj = kmem_cache_alloc_node(skb_small_head_cache,
@@ -576,7 +567,6 @@ static void *kmalloc_reserve(unsigned int *size, gfp_t flags, int node,
obj = kmem_cache_alloc_node(skb_small_head_cache, flags, node);
goto out;
}
-#endif
*size = obj_size = kmalloc_size_roundup(obj_size);
/*
* Try a regular allocation, when that fails and we're not entitled
@@ -898,11 +888,9 @@ static bool skb_pp_recycle(struct sk_buff *skb, void *data, bool napi_safe)
static void skb_kfree_head(void *head, unsigned int end_offset)
{
-#ifdef HAVE_SKB_SMALL_HEAD_CACHE
if (end_offset == SKB_SMALL_HEAD_HEADROOM)
kmem_cache_free(skb_small_head_cache, head);
else
-#endif
kfree(head);
}
@@ -2160,7 +2148,6 @@ int __skb_unclone_keeptruesize(struct sk_buff *skb, gfp_t pri)
if (likely(skb_end_offset(skb) == saved_end_offset))
return 0;
-#ifdef HAVE_SKB_SMALL_HEAD_CACHE
/* We can not change skb->end if the original or new value
* is SKB_SMALL_HEAD_HEADROOM, as it might break skb_kfree_head().
*/
@@ -2174,7 +2161,6 @@ int __skb_unclone_keeptruesize(struct sk_buff *skb, gfp_t pri)
WARN_ON_ONCE(1);
return 0;
}
-#endif
shinfo = skb_shinfo(skb);
@@ -3003,32 +2989,32 @@ int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
}
EXPORT_SYMBOL_GPL(skb_splice_bits);
-static int sendmsg_unlocked(struct sock *sk, struct msghdr *msg,
- struct kvec *vec, size_t num, size_t size)
+static int sendmsg_locked(struct sock *sk, struct msghdr *msg)
{
struct socket *sock = sk->sk_socket;
+ size_t size = msg_data_left(msg);
if (!sock)
return -EINVAL;
- return kernel_sendmsg(sock, msg, vec, num, size);
+
+ if (!sock->ops->sendmsg_locked)
+ return sock_no_sendmsg_locked(sk, msg, size);
+
+ return sock->ops->sendmsg_locked(sk, msg, size);
}
-static int sendpage_unlocked(struct sock *sk, struct page *page, int offset,
- size_t size, int flags)
+static int sendmsg_unlocked(struct sock *sk, struct msghdr *msg)
{
struct socket *sock = sk->sk_socket;
if (!sock)
return -EINVAL;
- return kernel_sendpage(sock, page, offset, size, flags);
+ return sock_sendmsg(sock, msg);
}
-typedef int (*sendmsg_func)(struct sock *sk, struct msghdr *msg,
- struct kvec *vec, size_t num, size_t size);
-typedef int (*sendpage_func)(struct sock *sk, struct page *page, int offset,
- size_t size, int flags);
+typedef int (*sendmsg_func)(struct sock *sk, struct msghdr *msg);
static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset,
- int len, sendmsg_func sendmsg, sendpage_func sendpage)
+ int len, sendmsg_func sendmsg)
{
unsigned int orig_len = len;
struct sk_buff *head = skb;
@@ -3048,8 +3034,9 @@ do_frag_list:
memset(&msg, 0, sizeof(msg));
msg.msg_flags = MSG_DONTWAIT;
- ret = INDIRECT_CALL_2(sendmsg, kernel_sendmsg_locked,
- sendmsg_unlocked, sk, &msg, &kv, 1, slen);
+ iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &kv, 1, slen);
+ ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked,
+ sendmsg_unlocked, sk, &msg);
if (ret <= 0)
goto error;
@@ -3080,11 +3067,18 @@ do_frag_list:
slen = min_t(size_t, len, skb_frag_size(frag) - offset);
while (slen) {
- ret = INDIRECT_CALL_2(sendpage, kernel_sendpage_locked,
- sendpage_unlocked, sk,
- skb_frag_page(frag),
- skb_frag_off(frag) + offset,
- slen, MSG_DONTWAIT);
+ struct bio_vec bvec;
+ struct msghdr msg = {
+ .msg_flags = MSG_SPLICE_PAGES | MSG_DONTWAIT,
+ };
+
+ bvec_set_page(&bvec, skb_frag_page(frag), slen,
+ skb_frag_off(frag) + offset);
+ iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1,
+ slen);
+
+ ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked,
+ sendmsg_unlocked, sk, &msg);
if (ret <= 0)
goto error;
@@ -3121,16 +3115,14 @@ error:
int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset,
int len)
{
- return __skb_send_sock(sk, skb, offset, len, kernel_sendmsg_locked,
- kernel_sendpage_locked);
+ return __skb_send_sock(sk, skb, offset, len, sendmsg_locked);
}
EXPORT_SYMBOL_GPL(skb_send_sock_locked);
/* Send skb data on a socket. Socket must be unlocked. */
int skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len)
{
- return __skb_send_sock(sk, skb, offset, len, sendmsg_unlocked,
- sendpage_unlocked);
+ return __skb_send_sock(sk, skb, offset, len, sendmsg_unlocked);
}
/**
@@ -4203,13 +4195,13 @@ unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
EXPORT_SYMBOL(skb_find_text);
int skb_append_pagefrags(struct sk_buff *skb, struct page *page,
- int offset, size_t size)
+ int offset, size_t size, size_t max_frags)
{
int i = skb_shinfo(skb)->nr_frags;
if (skb_can_coalesce(skb, i, page, offset)) {
skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], size);
- } else if (i < MAX_SKB_FRAGS) {
+ } else if (i < max_frags) {
skb_zcopy_downgrade_managed(skb);
get_page(page);
skb_fill_page_desc_noacc(skb, i, page, offset, size);
@@ -4249,10 +4241,9 @@ static inline skb_frag_t skb_head_frag_to_page_desc(struct sk_buff *frag_skb)
struct page *page;
page = virt_to_head_page(frag_skb->head);
- __skb_frag_set_page(&head_frag, page);
- skb_frag_off_set(&head_frag, frag_skb->data -
- (unsigned char *)page_address(page));
- skb_frag_size_set(&head_frag, skb_headlen(frag_skb));
+ skb_frag_fill_page_desc(&head_frag, page, frag_skb->data -
+ (unsigned char *)page_address(page),
+ skb_headlen(frag_skb));
return head_frag;
}
@@ -4768,7 +4759,6 @@ void __init skb_init(void)
0,
SLAB_HWCACHE_ALIGN|SLAB_PANIC,
NULL);
-#ifdef HAVE_SKB_SMALL_HEAD_CACHE
/* usercopy should only access first SKB_SMALL_HEAD_HEADROOM bytes.
* struct skb_shared_info is located at the end of skb->head,
* and should not be copied to/from user.
@@ -4780,7 +4770,6 @@ void __init skb_init(void)
0,
SKB_SMALL_HEAD_HEADROOM,
NULL);
-#endif
skb_extensions_init();
}
@@ -5784,147 +5773,6 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet)
}
EXPORT_SYMBOL_GPL(skb_scrub_packet);
-/**
- * skb_gso_transport_seglen - Return length of individual segments of a gso packet
- *
- * @skb: GSO skb
- *
- * skb_gso_transport_seglen is used to determine the real size of the
- * individual segments, including Layer4 headers (TCP/UDP).
- *
- * The MAC/L2 or network (IP, IPv6) headers are not accounted for.
- */
-static unsigned int skb_gso_transport_seglen(const struct sk_buff *skb)
-{
- const struct skb_shared_info *shinfo = skb_shinfo(skb);
- unsigned int thlen = 0;
-
- if (skb->encapsulation) {
- thlen = skb_inner_transport_header(skb) -
- skb_transport_header(skb);
-
- if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
- thlen += inner_tcp_hdrlen(skb);
- } else if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
- thlen = tcp_hdrlen(skb);
- } else if (unlikely(skb_is_gso_sctp(skb))) {
- thlen = sizeof(struct sctphdr);
- } else if (shinfo->gso_type & SKB_GSO_UDP_L4) {
- thlen = sizeof(struct udphdr);
- }
- /* UFO sets gso_size to the size of the fragmentation
- * payload, i.e. the size of the L4 (UDP) header is already
- * accounted for.
- */
- return thlen + shinfo->gso_size;
-}
-
-/**
- * skb_gso_network_seglen - Return length of individual segments of a gso packet
- *
- * @skb: GSO skb
- *
- * skb_gso_network_seglen is used to determine the real size of the
- * individual segments, including Layer3 (IP, IPv6) and L4 headers (TCP/UDP).
- *
- * The MAC/L2 header is not accounted for.
- */
-static unsigned int skb_gso_network_seglen(const struct sk_buff *skb)
-{
- unsigned int hdr_len = skb_transport_header(skb) -
- skb_network_header(skb);
-
- return hdr_len + skb_gso_transport_seglen(skb);
-}
-
-/**
- * skb_gso_mac_seglen - Return length of individual segments of a gso packet
- *
- * @skb: GSO skb
- *
- * skb_gso_mac_seglen is used to determine the real size of the
- * individual segments, including MAC/L2, Layer3 (IP, IPv6) and L4
- * headers (TCP/UDP).
- */
-static unsigned int skb_gso_mac_seglen(const struct sk_buff *skb)
-{
- unsigned int hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
-
- return hdr_len + skb_gso_transport_seglen(skb);
-}
-
-/**
- * skb_gso_size_check - check the skb size, considering GSO_BY_FRAGS
- *
- * There are a couple of instances where we have a GSO skb, and we
- * want to determine what size it would be after it is segmented.
- *
- * We might want to check:
- * - L3+L4+payload size (e.g. IP forwarding)
- * - L2+L3+L4+payload size (e.g. sanity check before passing to driver)
- *
- * This is a helper to do that correctly considering GSO_BY_FRAGS.
- *
- * @skb: GSO skb
- *
- * @seg_len: The segmented length (from skb_gso_*_seglen). In the
- * GSO_BY_FRAGS case this will be [header sizes + GSO_BY_FRAGS].
- *
- * @max_len: The maximum permissible length.
- *
- * Returns true if the segmented length <= max length.
- */
-static inline bool skb_gso_size_check(const struct sk_buff *skb,
- unsigned int seg_len,
- unsigned int max_len) {
- const struct skb_shared_info *shinfo = skb_shinfo(skb);
- const struct sk_buff *iter;
-
- if (shinfo->gso_size != GSO_BY_FRAGS)
- return seg_len <= max_len;
-
- /* Undo this so we can re-use header sizes */
- seg_len -= GSO_BY_FRAGS;
-
- skb_walk_frags(skb, iter) {
- if (seg_len + skb_headlen(iter) > max_len)
- return false;
- }
-
- return true;
-}
-
-/**
- * skb_gso_validate_network_len - Will a split GSO skb fit into a given MTU?
- *
- * @skb: GSO skb
- * @mtu: MTU to validate against
- *
- * skb_gso_validate_network_len validates if a given skb will fit a
- * wanted MTU once split. It considers L3 headers, L4 headers, and the
- * payload.
- */
-bool skb_gso_validate_network_len(const struct sk_buff *skb, unsigned int mtu)
-{
- return skb_gso_size_check(skb, skb_gso_network_seglen(skb), mtu);
-}
-EXPORT_SYMBOL_GPL(skb_gso_validate_network_len);
-
-/**
- * skb_gso_validate_mac_len - Will a split GSO skb fit in a given length?
- *
- * @skb: GSO skb
- * @len: length to validate against
- *
- * skb_gso_validate_mac_len validates if a given skb will fit a wanted
- * length once split, including L2, L3 and L4 headers and the payload.
- */
-bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len)
-{
- return skb_gso_size_check(skb, skb_gso_mac_seglen(skb), len);
-}
-EXPORT_SYMBOL_GPL(skb_gso_validate_mac_len);
-
static struct sk_buff *skb_reorder_vlan_header(struct sk_buff *skb)
{
int mac_len, meta_len;
@@ -6912,3 +6760,91 @@ nodefer: __kfree_skb(skb);
if (unlikely(kick) && !cmpxchg(&sd->defer_ipi_scheduled, 0, 1))
smp_call_function_single_async(cpu, &sd->defer_csd);
}
+
+static void skb_splice_csum_page(struct sk_buff *skb, struct page *page,
+ size_t offset, size_t len)
+{
+ const char *kaddr;
+ __wsum csum;
+
+ kaddr = kmap_local_page(page);
+ csum = csum_partial(kaddr + offset, len, 0);
+ kunmap_local(kaddr);
+ skb->csum = csum_block_add(skb->csum, csum, skb->len);
+}
+
+/**
+ * skb_splice_from_iter - Splice (or copy) pages to skbuff
+ * @skb: The buffer to add pages to
+ * @iter: Iterator representing the pages to be added
+ * @maxsize: Maximum amount of pages to be added
+ * @gfp: Allocation flags
+ *
+ * This is a common helper function for supporting MSG_SPLICE_PAGES. It
+ * extracts pages from an iterator and adds them to the socket buffer if
+ * possible, copying them to fragments if not possible (such as if they're slab
+ * pages).
+ *
+ * Returns the amount of data spliced/copied or -EMSGSIZE if there's
+ * insufficient space in the buffer to transfer anything.
+ */
+ssize_t skb_splice_from_iter(struct sk_buff *skb, struct iov_iter *iter,
+ ssize_t maxsize, gfp_t gfp)
+{
+ size_t frag_limit = READ_ONCE(sysctl_max_skb_frags);
+ struct page *pages[8], **ppages = pages;
+ ssize_t spliced = 0, ret = 0;
+ unsigned int i;
+
+ while (iter->count > 0) {
+ ssize_t space, nr, len;
+ size_t off;
+
+ ret = -EMSGSIZE;
+ space = frag_limit - skb_shinfo(skb)->nr_frags;
+ if (space < 0)
+ break;
+
+ /* We might be able to coalesce without increasing nr_frags */
+ nr = clamp_t(size_t, space, 1, ARRAY_SIZE(pages));
+
+ len = iov_iter_extract_pages(iter, &ppages, maxsize, nr, 0, &off);
+ if (len <= 0) {
+ ret = len ?: -EIO;
+ break;
+ }
+
+ i = 0;
+ do {
+ struct page *page = pages[i++];
+ size_t part = min_t(size_t, PAGE_SIZE - off, len);
+
+ ret = -EIO;
+ if (WARN_ON_ONCE(!sendpage_ok(page)))
+ goto out;
+
+ ret = skb_append_pagefrags(skb, page, off, part,
+ frag_limit);
+ if (ret < 0) {
+ iov_iter_revert(iter, len);
+ goto out;
+ }
+
+ if (skb->ip_summed == CHECKSUM_NONE)
+ skb_splice_csum_page(skb, page, off, part);
+
+ off = 0;
+ spliced += part;
+ maxsize -= part;
+ len -= part;
+ } while (len > 0);
+
+ if (maxsize <= 0)
+ break;
+ }
+
+out:
+ skb_len_add(skb, spliced);
+ return spliced ?: ret;
+}
+EXPORT_SYMBOL(skb_splice_from_iter);