[PATCH AUTOSEL 4.19 157/237] hfsplus: fix return value of hfsplus_get_block()

Sasha Levin
2019-11-16T15:45:29Z

From: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>

[ Upstream commit 839c3a6a5e1fbc8542d581911b35b2cb5cd29304 ]

Direct writes to empty inodes fail with EIO. The generic direct-io code
is in part to blame (a patch has been submitted as "direct-io: allow
direct writes to empty inodes"), but hfsplus is worse affected than the
other filesystems because the fallback to buffered I/O doesn't happen.

The problem is the return value of hfsplus_get_block() when called with
!create. Change it to be more consistent with the other modules.

Link: http://lkml.kernel.org/r/2cd1301404ec7cf1e39c8f11a01a4302f1460ad6.1539195310.git.ernesto.mnd.fernandez@gmail.com
Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/hfsplus/extents.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/hfsplus/extents.c b/fs/hfsplus/extents.c
index 8a8893d522ef3..a930ddd156819 100644
--- a/fs/hfsplus/extents.c
+++ b/fs/hfsplus/extents.c
@@ -237,7 +237,9 @@ int hfsplus_get_block(struct inode *inode, sector_t iblock,
ablock = iblock >> sbi->fs_shift;

if (iblock >= hip->fs_blocks) {
- if (iblock > hip->fs_blocks || !create)
+ if (!create)
+ return 0;
+ if (iblock > hip->fs_blocks)
return -EIO;
if (ablock >= hip->alloc_blocks) {
res = hfsplus_file_extend(inode, false);
--
2.20.1