diff options
Diffstat (limited to 'net/core')
-rw-r--r-- | net/core/iovec.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/net/core/iovec.c b/net/core/iovec.c index de178e4..b77eeec 100644 --- a/net/core/iovec.c +++ b/net/core/iovec.c @@ -212,3 +212,27 @@ out_fault: goto out; } EXPORT_SYMBOL(csum_partial_copy_fromiovecend); + +unsigned long iov_pages(const struct iovec *iov, int offset, + unsigned long nr_segs) +{ + unsigned long seg, base; + int pages = 0, len, size; + + while (nr_segs && (offset >= iov->iov_len)) { + offset -= iov->iov_len; + ++iov; + --nr_segs; + } + + for (seg = 0; seg < nr_segs; seg++) { + base = (unsigned long)iov[seg].iov_base + offset; + len = iov[seg].iov_len - offset; + size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT; + pages += size; + offset = 0; + } + + return pages; +} +EXPORT_SYMBOL(iov_pages); |