diff options
| -rw-r--r-- | include/linux/skbuff.h | 9 | ||||
| -rw-r--r-- | net/core/skbuff.c | 53 |
2 files changed, 45 insertions, 17 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index be76082f48aa..2f64e2bbb592 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1796,13 +1796,18 @@ static inline unsigned int skb_headlen(const struct sk_buff *skb) return skb->len - skb->data_len; } -static inline unsigned int skb_pagelen(const struct sk_buff *skb) +static inline unsigned int __skb_pagelen(const struct sk_buff *skb) { unsigned int i, len = 0; for (i = skb_shinfo(skb)->nr_frags - 1; (int)i >= 0; i--) len += skb_frag_size(&skb_shinfo(skb)->frags[i]); - return len + skb_headlen(skb); + return len; +} + +static inline unsigned int skb_pagelen(const struct sk_buff *skb) +{ + return skb_headlen(skb) + __skb_pagelen(skb); } /** diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 0f0933b338d7..a95877a8ac8b 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -932,17 +932,20 @@ EXPORT_SYMBOL_GPL(skb_morph); */ int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) { - int i; + struct ubuf_info *uarg = skb_shinfo(skb)->destructor_arg; int num_frags = skb_shinfo(skb)->nr_frags; struct page *page, *head = NULL; - struct ubuf_info *uarg = skb_shinfo(skb)->destructor_arg; + int i, new_frags; + u32 d_off; - for (i = 0; i < num_frags; i++) { - skb_frag_t *f = &skb_shinfo(skb)->frags[i]; - u32 p_off, p_len, copied; - struct page *p; - u8 *vaddr; + if (!num_frags) + return 0; + + if (skb_shared(skb) || skb_unclone(skb, gfp_mask)) + return -EINVAL; + new_frags = (__skb_pagelen(skb) + PAGE_SIZE - 1) >> PAGE_SHIFT; + for (i = 0; i < new_frags; i++) { page = alloc_page(gfp_mask); if (!page) { while (head) { @@ -952,17 +955,36 @@ int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) } return -ENOMEM; } + set_page_private(page, (unsigned long)head); + head = page; + } + + page = head; + d_off = 0; + for (i = 0; i < num_frags; i++) { + skb_frag_t *f = &skb_shinfo(skb)->frags[i]; + u32 p_off, p_len, copied; + struct page *p; + u8 *vaddr; skb_frag_foreach_page(f, f->page_offset, skb_frag_size(f), p, p_off, p_len, copied) { + u32 copy, done = 0; vaddr = kmap_atomic(p); - memcpy(page_address(page) + copied, vaddr + p_off, - p_len); + + while (done < p_len) { + if (d_off == PAGE_SIZE) { + d_off = 0; + page = (struct page *)page_private(page); + } + copy = min_t(u32, PAGE_SIZE - d_off, p_len - done); + memcpy(page_address(page) + d_off, + vaddr + p_off + done, copy); + done += copy; + d_off += copy; + } kunmap_atomic(vaddr); } - - set_page_private(page, (unsigned long)head); - head = page; } /* skb frags release userspace buffers */ @@ -972,11 +994,12 @@ int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) uarg->callback(uarg, false); /* skb frags point to kernel buffers */ - for (i = num_frags - 1; i >= 0; i--) { - __skb_fill_page_desc(skb, i, head, 0, - skb_shinfo(skb)->frags[i].size); + for (i = 0; i < new_frags - 1; i++) { + __skb_fill_page_desc(skb, i, head, 0, PAGE_SIZE); head = (struct page *)page_private(head); } + __skb_fill_page_desc(skb, new_frags - 1, head, 0, d_off); + skb_shinfo(skb)->nr_frags = new_frags; skb_shinfo(skb)->tx_flags &= ~SKBTX_DEV_ZEROCOPY; return 0; |