diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/datagram.c | 136 |
1 files changed, 42 insertions, 94 deletions
diff --git a/net/core/datagram.c b/net/core/datagram.c index abe642181b64..382543302ae5 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -408,27 +408,20 @@ int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags) } EXPORT_SYMBOL(skb_kill_datagram); -/** - * skb_copy_datagram_iter - Copy a datagram to an iovec iterator. - * @skb: buffer to copy - * @offset: offset in the buffer to start copying from - * @to: iovec iterator to copy to - * @len: amount of data to copy from buffer to iovec - */ -int skb_copy_datagram_iter(const struct sk_buff *skb, int offset, - struct iov_iter *to, int len) +int __skb_datagram_iter(const struct sk_buff *skb, int offset, + struct iov_iter *to, int len, bool fault_short, + size_t (*cb)(const void *, size_t, void *, struct iov_iter *), + void *data) { int start = skb_headlen(skb); int i, copy = start - offset, start_off = offset, n; struct sk_buff *frag_iter; - trace_skb_copy_datagram_iovec(skb, len); - /* Copy header. */ if (copy > 0) { if (copy > len) copy = len; - n = copy_to_iter(skb->data + offset, copy, to); + n = cb(skb->data + offset, copy, data, to); offset += n; if (n != copy) goto short_copy; @@ -450,8 +443,8 @@ int skb_copy_datagram_iter(const struct sk_buff *skb, int offset, if (copy > len) copy = len; - n = copy_to_iter(vaddr + frag->page_offset + - offset - start, copy, to); + n = cb(vaddr + frag->page_offset + + offset - start, copy, data, to); kunmap(page); offset += n; if (n != copy) @@ -471,8 +464,8 @@ int skb_copy_datagram_iter(const struct sk_buff *skb, int offset, if ((copy = end - offset) > 0) { if (copy > len) copy = len; - if (skb_copy_datagram_iter(frag_iter, offset - start, - to, copy)) + if (__skb_datagram_iter(frag_iter, offset - start, + to, copy, short_copy, cb, data)) goto fault; if ((len -= copy) == 0) return 0; @@ -493,11 +486,32 @@ fault: return -EFAULT; short_copy: - if (iov_iter_count(to)) + if (fault_short || iov_iter_count(to)) goto fault; return 0; } + +static size_t simple_copy_to_iter(const void *addr, size_t bytes, + void *data __always_unused, struct iov_iter *i) +{ + return copy_to_iter(addr, bytes, i); +} + +/** + * skb_copy_datagram_iter - Copy a datagram to an iovec iterator. + * @skb: buffer to copy + * @offset: offset in the buffer to start copying from + * @to: iovec iterator to copy to + * @len: amount of data to copy from buffer to iovec + */ +int skb_copy_datagram_iter(const struct sk_buff *skb, int offset, + struct iov_iter *to, int len) +{ + trace_skb_copy_datagram_iovec(skb, len); + return __skb_datagram_iter(skb, offset, to, len, false, + simple_copy_to_iter, NULL); +} EXPORT_SYMBOL(skb_copy_datagram_iter); /** @@ -648,87 +662,21 @@ int zerocopy_sg_from_iter(struct sk_buff *skb, struct iov_iter *from) } EXPORT_SYMBOL(zerocopy_sg_from_iter); +/** + * skb_copy_and_csum_datagram_iter - Copy datagram to an iovec iterator + * and update a checksum. + * @skb: buffer to copy + * @offset: offset in the buffer to start copying from + * @to: iovec iterator to copy to + * @len: amount of data to copy from buffer to iovec + * @csump: checksum pointer + */ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, struct iov_iter *to, int len, __wsum *csump) { - int start = skb_headlen(skb); - int i, copy = start - offset, start_off = offset; - struct sk_buff *frag_iter; - int pos = 0; - int n; - - /* Copy header. */ - if (copy > 0) { - if (copy > len) - copy = len; - n = csum_and_copy_to_iter(skb->data + offset, copy, csump, to); - offset += n; - if (n != copy) - goto fault; - if ((len -= copy) == 0) - return 0; - pos = copy; - } - - for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - int end; - const skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; - - WARN_ON(start > offset + len); - - end = start + skb_frag_size(frag); - if ((copy = end - offset) > 0) { - __wsum csum2 = 0; - struct page *page = skb_frag_page(frag); - u8 *vaddr = kmap(page); - - if (copy > len) - copy = len; - n = csum_and_copy_to_iter(vaddr + frag->page_offset + - offset - start, copy, - &csum2, to); - kunmap(page); - offset += n; - if (n != copy) - goto fault; - *csump = csum_block_add(*csump, csum2, pos); - if (!(len -= copy)) - return 0; - pos += copy; - } - start = end; - } - - skb_walk_frags(skb, frag_iter) { - int end; - - WARN_ON(start > offset + len); - - end = start + frag_iter->len; - if ((copy = end - offset) > 0) { - __wsum csum2 = 0; - if (copy > len) - copy = len; - if (skb_copy_and_csum_datagram(frag_iter, - offset - start, - to, copy, - &csum2)) - goto fault; - *csump = csum_block_add(*csump, csum2, pos); - if ((len -= copy) == 0) - return 0; - offset += copy; - pos += copy; - } - start = end; - } - if (!len) - return 0; - -fault: - iov_iter_revert(to, offset - start_off); - return -EFAULT; + return __skb_datagram_iter(skb, offset, to, len, true, + csum_and_copy_to_iter, csump); } __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len) |