[patch 1/6] revert "generic_file_buffered_write(): handle zero length iovec segments"

Andrew Morton
2006-10-11T06:17:51Z

Revert 81b0c8713385ce1b1b9058e916edcf9561ad76d6.

This was a bugfix against 6527c2bdf1f833cc18e8f42bd97973d583e4aa83, which we
also revert.

Signed-off-by: Andrew Morton <akpm@osdl.org>
---

mm/filemap.c | 9 +--------
mm/filemap.h | 4 ++--
2 files changed, 3 insertions(+), 10 deletions(-)

diff -puN mm/filemap.c~revert-generic_file_buffered_write-handle-zero-length-iovec-segments mm/filemap.c
--- a/mm/filemap.c~revert-generic_file_buffered_write-handle-zero-length-iovec-segments
+++ a/mm/filemap.c
@@ -2121,12 +2121,6 @@ generic_file_buffered_write(struct kiocb
break;
}

- if (unlikely(bytes == 0)) {
- status = 0;
- copied = 0;
- goto zero_length_segment;
- }
-
status = a_ops->prepare_write(file, page, offset, offset+bytes);
if (unlikely(status)) {
loff_t isize = i_size_read(inode);
@@ -2156,8 +2150,7 @@ generic_file_buffered_write(struct kiocb
page_cache_release(page);
continue;
}
-zero_length_segment:
- if (likely(copied >= 0)) {
+ if (likely(copied > 0)) {
if (!status)
status = copied;

diff -puN mm/filemap.h~revert-generic_file_buffered_write-handle-zero-length-iovec-segments mm/filemap.h
--- a/mm/filemap.h~revert-generic_file_buffered_write-handle-zero-length-iovec-segments
+++ a/mm/filemap.h
@@ -87,7 +87,7 @@ filemap_set_next_iovec(const struct iove
const struct iovec *iov = *iovp;
size_t base = *basep;

- do {
+ while (bytes) {
int copy = min(bytes, iov->iov_len - base);

bytes -= copy;
@@ -96,7 +96,7 @@ filemap_set_next_iovec(const struct iove
iov++;
base = 0;
}
- } while (bytes);
+ }
*iovp = iov;
*basep = base;
}
_