Re: [PATCH V7 06/17] xfs: Promote xfs_extnum_t and xfs_aextnum_t to 64 and 32-bits respectively

Chandan Babu R
2022-03-05T12:43:43Z

On 04 Mar 2022 at 06:59, Dave Chinner wrote:
> On Tue, Mar 01, 2022 at 04:09:27PM +0530, Chandan Babu R wrote:
>> A future commit will introduce a 64-bit on-disk data extent counter and a
>> 32-bit on-disk attr extent counter. This commit promotes xfs_extnum_t and
>> xfs_aextnum_t to 64 and 32-bits in order to correctly handle in-core versions
>> of these quantities.
>>
>> Reported-by: kernel test robot <lkp@intel.com>
>
> What was reported by the test robot? This change isn't a bug that
> needed fixing, it's a core part of the patchset...
>

Kernel test robot had complained about the following,

ld.lld: error: undefined symbol: __udivdi3
>>> referenced by xfs_bmap.c
>>> xfs/libxfs/xfs_bmap.o:(xfs_bmap_compute_maxlevels) in archive fs/built-in.a

I had solved the linker error by replacing the division operation with the
following statement,

maxblocks = howmany_64(maxleafents, minleafrecs);

Sorry, I will include this description in the commit message.

>> Reviewed-by: Darrick J. Wong <djwong@kernel.org>
>> Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
>> ---
>> fs/xfs/libxfs/xfs_bmap.c | 6 +++---
>> fs/xfs/libxfs/xfs_inode_fork.c | 2 +-
>> fs/xfs/libxfs/xfs_inode_fork.h | 2 +-
>> fs/xfs/libxfs/xfs_types.h | 4 ++--
>> fs/xfs/xfs_inode.c | 4 ++--
>> fs/xfs/xfs_trace.h | 2 +-
>> 6 files changed, 10 insertions(+), 10 deletions(-)
>>
>> diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
>> index 98541be873d8..9df98339a43a 100644
>> --- a/fs/xfs/libxfs/xfs_bmap.c
>> +++ b/fs/xfs/libxfs/xfs_bmap.c
>> @@ -52,9 +52,9 @@ xfs_bmap_compute_maxlevels(
>> xfs_mount_t *mp, /* file system mount structure */
>> int whichfork) /* data or attr fork */
>> {
>> + xfs_extnum_t maxleafents; /* max leaf entries possible */
>> int level; /* btree level */
>> uint maxblocks; /* max blocks at this level */
>> - xfs_extnum_t maxleafents; /* max leaf entries possible */
>> int maxrootrecs; /* max records in root block */
>> int minleafrecs; /* min records in leaf block */
>> int minnoderecs; /* min records in node block */
>
> Unnecessary.
>

I agree. I will revert the above change.

>> @@ -83,7 +83,7 @@ xfs_bmap_compute_maxlevels(
>> maxrootrecs = xfs_bmdr_maxrecs(sz, 0);
>> minleafrecs = mp->m_bmap_dmnr[0];
>> minnoderecs = mp->m_bmap_dmnr[1];
>> - maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
>> + maxblocks = howmany_64(maxleafents, minleafrecs);
>> for (level = 1; maxblocks > 1; level++) {
>> if (maxblocks <= maxrootrecs)
>> maxblocks = 1;
>> @@ -467,7 +467,7 @@ xfs_bmap_check_leaf_extents(
>> if (bp_release)
>> xfs_trans_brelse(NULL, bp);
>> error_norelse:
>> - xfs_warn(mp, "%s: BAD after btree leaves for %d extents",
>> + xfs_warn(mp, "%s: BAD after btree leaves for %llu extents",
>> __func__, i);
>> xfs_err(mp, "%s: CORRUPTED BTREE OR SOMETHING", __func__);
>> xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
>> diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c
>> index 829739e249b6..ce690abe5dce 100644
>> --- a/fs/xfs/libxfs/xfs_inode_fork.c
>> +++ b/fs/xfs/libxfs/xfs_inode_fork.c
>> @@ -117,7 +117,7 @@ xfs_iformat_extents(
>> * we just bail out rather than crash in kmem_alloc() or memcpy() below.
>> */
>> if (unlikely(size < 0 || size > XFS_DFORK_SIZE(dip, mp, whichfork))) {
>> - xfs_warn(ip->i_mount, "corrupt inode %Lu ((a)extents = %d).",
>> + xfs_warn(ip->i_mount, "corrupt inode %llu ((a)extents = %llu).",
>> (unsigned long long) ip->i_ino, nex);
>
> Isn't ip->i_ino explicitly defined as an unsigned long long? If you are going
> to fix one part of the printk formatting for ip->i_ino, you should
> probably should get rid of the unnecessary cast, too.

Yes, xfs_ino_t is an alias for "unsigned long long". I will remove the
typecast.

>
> Otherwise looks OK.

--
chandan