[PATCH v4 5/9] iomap: drop the write failure handles when unsharing and zeroing

From: Zhang Yi
Date: Wed Mar 20 2024 - 07:14:14 EST


From: Zhang Yi <yi.zhang@xxxxxxxxxx>

Unsharing and zeroing can only happen within EOF, so there is never a
need to perform posteof pagecache truncation if write begin fails, also
partial write could never theoretically happened from iomap_write_end(),
so remove both of them.

Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
fs/iomap/buffered-io.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 093c4515b22a..7e32a204650b 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -786,7 +786,6 @@ static int iomap_write_begin(struct iomap_iter *iter, loff_t pos,

out_unlock:
__iomap_put_folio(iter, pos, 0, folio);
- iomap_write_failed(iter->inode, pos, len);

return status;
}
@@ -863,8 +862,6 @@ static size_t iomap_write_end(struct iomap_iter *iter, loff_t pos, size_t len,

if (old_size < pos)
pagecache_isize_extended(iter->inode, old_size, pos);
- if (ret < len)
- iomap_write_failed(iter->inode, pos + ret, len - ret);
return ret;
}

@@ -912,8 +909,10 @@ static loff_t iomap_write_iter(struct iomap_iter *iter, struct iov_iter *i)
}

status = iomap_write_begin(iter, pos, bytes, &folio);
- if (unlikely(status))
+ if (unlikely(status)) {
+ iomap_write_failed(iter->inode, pos, bytes);
break;
+ }
if (iter->iomap.flags & IOMAP_F_STALE)
break;

@@ -927,6 +926,9 @@ static loff_t iomap_write_iter(struct iomap_iter *iter, struct iov_iter *i)
copied = copy_folio_from_iter_atomic(folio, offset, bytes, i);
status = iomap_write_end(iter, pos, bytes, copied, folio);

+ if (status < bytes)
+ iomap_write_failed(iter->inode, pos + status,
+ bytes - status);
if (unlikely(copied != status))
iov_iter_revert(i, copied - status);

--
2.39.2