hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9DN5Z CVE: NA
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For now, we can make sure iomap_write_end() always return 0 or copied bytes, so instead of return written bytes, convert to return a boolean to indicate the copied bytes have been written to the pagecache.
Signed-off-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Darrick J. Wong djwong@kernel.org --- fs/iomap/buffered-io.c | 48 +++++++++++++++++++++++++++--------------- 1 file changed, 31 insertions(+), 17 deletions(-)
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 33d08bdf010d..b370ded823b0 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -825,7 +825,7 @@ static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, return status; }
-static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len, +static bool __iomap_write_end(struct inode *inode, loff_t pos, size_t len, size_t copied, struct folio *folio) { flush_dcache_folio(folio); @@ -842,14 +842,14 @@ static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len, * redo the whole thing. */ if (unlikely(copied < len && !folio_test_uptodate(folio))) - return 0; + return false; iomap_set_range_uptodate(folio, offset_in_folio(folio, pos), len); iomap_set_range_dirty(folio, offset_in_folio(folio, pos), copied); filemap_dirty_folio(inode->i_mapping, folio); - return copied; + return true; }
-static size_t iomap_write_end_inline(const struct iomap_iter *iter, +static void iomap_write_end_inline(const struct iomap_iter *iter, struct folio *folio, loff_t pos, size_t copied) { const struct iomap *iomap = &iter->iomap; @@ -864,20 +864,31 @@ static size_t iomap_write_end_inline(const struct iomap_iter *iter, kunmap_local(addr);
mark_inode_dirty(iter->inode); - return copied; }
-/* Returns the number of bytes copied. May be 0. Cannot be an errno. */ -static size_t iomap_write_end(struct iomap_iter *iter, loff_t pos, size_t len, +/* + * Returns true if all copied bytes have been written to the pagecache, + * otherwise return false. + */ +static bool iomap_write_end(struct iomap_iter *iter, loff_t pos, size_t len, size_t copied, struct folio *folio) { const struct iomap *srcmap = iomap_iter_srcmap(iter);
- if (srcmap->type == IOMAP_INLINE) - return iomap_write_end_inline(iter, folio, pos, copied); - if (srcmap->flags & IOMAP_F_BUFFER_HEAD) - return block_write_end(NULL, iter->inode->i_mapping, pos, len, - copied, &folio->page, NULL); + if (srcmap->type == IOMAP_INLINE) { + iomap_write_end_inline(iter, folio, pos, copied); + return true; + } + + if (srcmap->flags & IOMAP_F_BUFFER_HEAD) { + size_t bh_written; + + bh_written = block_write_end(NULL, iter->inode->i_mapping, pos, + len, copied, &folio->page, NULL); + WARN_ON_ONCE(bh_written != copied && bh_written != 0); + return bh_written == copied; + } + return __iomap_write_end(iter->inode, pos, len, copied, folio); }
@@ -942,7 +953,8 @@ static loff_t iomap_write_iter(struct iomap_iter *iter, struct iov_iter *i) flush_dcache_folio(folio);
copied = copy_folio_from_iter_atomic(folio, offset, bytes, i); - written = iomap_write_end(iter, pos, bytes, copied, folio); + written = iomap_write_end(iter, pos, bytes, copied, folio) ? + copied : 0;
/* * Update the in-memory inode size after copying the data into @@ -1320,6 +1332,7 @@ static loff_t iomap_unshare_iter(struct iomap_iter *iter) int status; size_t offset; size_t bytes = min_t(u64, SIZE_MAX, length); + bool ret;
status = iomap_write_begin(iter, pos, bytes, &folio); if (unlikely(status)) @@ -1331,9 +1344,9 @@ static loff_t iomap_unshare_iter(struct iomap_iter *iter) if (bytes > folio_size(folio) - offset) bytes = folio_size(folio) - offset;
- bytes = iomap_write_end(iter, pos, bytes, bytes, folio); + ret = iomap_write_end(iter, pos, bytes, bytes, folio); __iomap_put_folio(iter, pos, bytes, folio); - if (WARN_ON_ONCE(bytes == 0)) + if (WARN_ON_ONCE(!ret)) return -EIO;
cond_resched(); @@ -1382,6 +1395,7 @@ static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero) int status; size_t offset; size_t bytes = min_t(u64, SIZE_MAX, length); + bool ret;
status = iomap_write_begin(iter, pos, bytes, &folio); if (status) @@ -1396,9 +1410,9 @@ static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero) folio_zero_range(folio, offset, bytes); folio_mark_accessed(folio);
- bytes = iomap_write_end(iter, pos, bytes, bytes, folio); + ret = iomap_write_end(iter, pos, bytes, bytes, folio); __iomap_put_folio(iter, pos, bytes, folio); - if (WARN_ON_ONCE(bytes == 0)) + if (WARN_ON_ONCE(!ret)) return -EIO;
pos += bytes;