diff options
author | H. Peter Anvin <hpa@zytor.com> | 2008-09-04 08:08:42 -0700 |
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committer | H. Peter Anvin <hpa@zytor.com> | 2008-09-04 08:08:42 -0700 |
commit | 7203781c98ad9147564d327de6f6513ad8fc0f4e (patch) | |
tree | 5c29a2a04a626bf08a0d56fd8a0068b3c92ad284 /net/core/datagram.c | |
parent | 671eef85a3e885dff4ce210d8774ad50a91d5967 (diff) | |
parent | af2e1f276ff08f17192411ea3b71c13a758dfe12 (diff) |
Merge branch 'x86/cpu' into x86/core
Conflicts:
arch/x86/kernel/cpu/feature_names.c
include/asm-x86/cpufeature.h
Diffstat (limited to 'net/core/datagram.c')
-rw-r--r-- | net/core/datagram.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/net/core/datagram.c b/net/core/datagram.c index dd61dcad601..52f577a0f54 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -339,6 +339,93 @@ fault: return -EFAULT; } +/** + * skb_copy_datagram_from_iovec - Copy a datagram from an iovec. + * @skb: buffer to copy + * @offset: offset in the buffer to start copying to + * @from: io vector to copy to + * @len: amount of data to copy to buffer from iovec + * + * Returns 0 or -EFAULT. + * Note: the iovec is modified during the copy. + */ +int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, + struct iovec *from, int len) +{ + int start = skb_headlen(skb); + int i, copy = start - offset; + + /* Copy header. */ + if (copy > 0) { + if (copy > len) + copy = len; + if (memcpy_fromiovec(skb->data + offset, from, copy)) + goto fault; + if ((len -= copy) == 0) + return 0; + offset += copy; + } + + /* Copy paged appendix. Hmm... why does this look so complicated? */ + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + int end; + + WARN_ON(start > offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; + if ((copy = end - offset) > 0) { + int err; + u8 *vaddr; + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + struct page *page = frag->page; + + if (copy > len) + copy = len; + vaddr = kmap(page); + err = memcpy_fromiovec(vaddr + frag->page_offset + + offset - start, from, copy); + kunmap(page); + if (err) + goto fault; + + if (!(len -= copy)) + return 0; + offset += copy; + } + start = end; + } + + if (skb_shinfo(skb)->frag_list) { + struct sk_buff *list = skb_shinfo(skb)->frag_list; + + for (; list; list = list->next) { + int end; + + WARN_ON(start > offset + len); + + end = start + list->len; + if ((copy = end - offset) > 0) { + if (copy > len) + copy = len; + if (skb_copy_datagram_from_iovec(list, + offset - start, + from, copy)) + goto fault; + if ((len -= copy) == 0) + return 0; + offset += copy; + } + start = end; + } + } + if (!len) + return 0; + +fault: + return -EFAULT; +} +EXPORT_SYMBOL(skb_copy_datagram_from_iovec); + static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset, u8 __user *to, int len, __wsum *csump) |