diff options
Diffstat (limited to 'mm')
-rw-r--r-- | mm/filemap.c | 9 | ||||
-rw-r--r-- | mm/filemap.h | 4 |
2 files changed, 10 insertions, 3 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index e5ac105ccd3..4655fa098d6 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2034,6 +2034,12 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, 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); @@ -2063,7 +2069,8 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, page_cache_release(page); continue; } - if (likely(copied > 0)) { +zero_length_segment: + if (likely(copied >= 0)) { if (!status) status = copied; diff --git a/mm/filemap.h b/mm/filemap.h index 13793ba0ce1..efd01426b5b 100644 --- a/mm/filemap.h +++ b/mm/filemap.h @@ -78,7 +78,7 @@ filemap_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes) const struct iovec *iov = *iovp; size_t base = *basep; - while (bytes) { + do { int copy = min(bytes, iov->iov_len - base); bytes -= copy; @@ -87,7 +87,7 @@ filemap_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes) iov++; base = 0; } - } + } while (bytes); *iovp = iov; *basep = base; } |