On 8/23/17 5:01 PM, Andreas Dilger wrote:
Doug,
I noticed while checking for other implications of changing MAX_LFS_FILESIZE
that fs/jfs/super.c is also working around this limit. If you are going
to submit a patch for this, it also makes sense to fix jfs_fill_super() to
use MAX_LFS_FILESIZE instead of JFS rolling its own, something like:
/* logical blocks are represented by 40 bits in pxd_t, etc.
* and page cache is indexed by long. */
sb->s_maxbytes = min((u64)sb->s_blocksize) << 40,
MAX_LFS_FILESIZE);
It also looks like ocfs2_max_file_offset() is trying to avoid overflowing
the old 31-bit limit, and isn't using MAX_LFS_FILESIZE directly, so it will
now be wrong. It looks like it could use "bitshift = 32; trim = bytes;",
but Joel or Mark should confirm.
Finally, there is a check in fs/super.c::mount_fs() that is verifying
s_maxbytes is not set too large, but this has been present since 2.6.32
and should probably be removed at this point, or changed to a BUG_ON()
(see commit 42cb56ae2ab for details).
I don't have any issue trying to write patches for those, but I have no
domain knowledge
in the area or any way to test them.
From a quick glance, jfs is locked to PSIZE (4096) so should be ok.
OCFS looks a little complex, and since it's a shared fs, little hesitant.
The check in fs/super.c, maybe that should be:
sb->s_maxbytes > MAX_LFS_FILESIZE
Actually, little confused, the comment says unsigned, but loff_t looks
like its long long.
Maybe cast to u64 and check greater than?
Doug
