[PATCH] afs: Fix large file support

[PATCH] afs: Fix large file support

[David Howells]

From: Marc Dionne <marc.dionne@auristor.com>

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@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
---

 fs/afs/super.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/afs/super.c b/fs/afs/super.c
index f18911e8d770..488641b1a418 100644
--- a/fs/afs/super.c
+++ b/fs/afs/super.c
@@ -435,6 +435,7 @@ static int afs_fill_super(struct super_block *sb, struct afs_fs_context *ctx)
 	/* 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;
 	if (!as->dyn_root)

Re: [PATCH] afs: Fix large file support

[David Howells]

Hi Linus,

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

Note that this isn't fixing a critical failure, so you might want to punt it
to the next cycle.

David