[PATCH 5.13 19/22] iomap: remove the length variable in iomap_seek_data

Greg Kroah-Hartman
2021-07-29T14:03:20Z

From: Christoph Hellwig <hch@lst.de>

[ Upstream commit 3ac1d426510f97ace05093ae9f2f710d9cbe6215 ]

The length variable is rather pointless given that it can be trivially
deduced from offset and size. Also the initial calculation can lead
to KASAN warnings.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Leizhen (ThunderTown) <thunder.leizhen@huawei.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/iomap/seek.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/fs/iomap/seek.c b/fs/iomap/seek.c
index dab1b02eba5b..50b8f1418f26 100644
--- a/fs/iomap/seek.c
+++ b/fs/iomap/seek.c
@@ -83,27 +83,23 @@ loff_t
iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops)
{
loff_t size = i_size_read(inode);
- loff_t length = size - offset;
loff_t ret;

/* Nothing to be found before or beyond the end of the file. */
if (offset < 0 || offset >= size)
return -ENXIO;

- while (length > 0) {
- ret = iomap_apply(inode, offset, length, IOMAP_REPORT, ops,
- &offset, iomap_seek_data_actor);
+ while (offset < size) {
+ ret = iomap_apply(inode, offset, size - offset, IOMAP_REPORT,
+ ops, &offset, iomap_seek_data_actor);
if (ret < 0)
return ret;
if (ret == 0)
- break;
-
+ return offset;
offset += ret;
- length -= ret;
}

- if (length <= 0)
- return -ENXIO;
- return offset;
+ /* We've reached the end of the file without finding data */
+ return -ENXIO;
}
EXPORT_SYMBOL_GPL(iomap_seek_data);
--
2.30.2