[PATCH 4.9 220/271] afs: Fix large file support

[Greg Kroah-Hartman]

From: Marc Dionne <marc.dionne@xxxxxxxxxxxx>

[ Upstream commit b485275f1aca8a9da37fd35e4fad673935e827da ]

By default s_maxbytes is set to MAX_NON_LFS, which limits the usable
file size to 2GB, enforced by the vfs.

Commit b9b1f8d5930a ("AFS: write support fixes") added support for the
64-bit fetch and store server operations, but did not change this value.
As a result, attempts to write past the 2G mark result in EFBIG errors:

 $ dd if=/dev/zero of=foo bs=1M count=1 seek=2048
 dd: error writing 'foo': File too large

Set s_maxbytes to MAX_LFS_FILESIZE.

Fixes: b9b1f8d5930a ("AFS: write support fixes")
Signed-off-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 fs/afs/super.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/afs/super.c b/fs/afs/super.c
index fbdb022b75a27..65389394e2028 100644
--- a/fs/afs/super.c
+++ b/fs/afs/super.c
@@ -317,6 +317,7 @@ static int afs_fill_super(struct super_block *sb,
 	/* fill in the superblock */
 	sb->s_blocksize		= PAGE_SIZE;
 	sb->s_blocksize_bits	= PAGE_SHIFT;
+	sb->s_maxbytes		= MAX_LFS_FILESIZE;
 	sb->s_magic		= AFS_FS_MAGIC;
 	sb->s_op		= &afs_super_ops;
 	sb->s_bdi		= &as->volume->bdi;
-- 
2.20.1