Re: [PATCH V9 18/19] xfs: Enable bulkstat ioctl to support 64-bit per-inode extent counters

Chandan Babu R
2022-04-07T08:20:39Z

On 07 Apr 2022 at 06:59, Darrick J. Wong wrote:
> On Wed, Apr 06, 2022 at 11:49:02AM +0530, Chandan Babu R wrote:
>> The following changes are made to enable userspace to obtain 64-bit extent
>> counters,
>> 1. Carve out a new 64-bit field xfs_bulkstat->bs_extents64 from
>> xfs_bulkstat->bs_pad[] to hold 64-bit extent counter.
>> 2. Define the new flag XFS_BULK_IREQ_BULKSTAT for userspace to indicate that
>> it is capable of receiving 64-bit extent counters.
>>
>> Reviewed-by: Dave Chinner <dchinner@redhat.com>
>> Suggested-by: Darrick J. Wong <djwong@kernel.org>
>> Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
>> ---
>> fs/xfs/libxfs/xfs_fs.h | 20 ++++++++++++++++----
>> fs/xfs/xfs_ioctl.c | 3 +++
>> fs/xfs/xfs_itable.c | 13 ++++++++++++-
>> fs/xfs/xfs_itable.h | 2 ++
>> 4 files changed, 33 insertions(+), 5 deletions(-)
>>
>> diff --git a/fs/xfs/libxfs/xfs_fs.h b/fs/xfs/libxfs/xfs_fs.h
>> index 1f7238db35cc..2a42bfb85c3b 100644
>> --- a/fs/xfs/libxfs/xfs_fs.h
>> +++ b/fs/xfs/libxfs/xfs_fs.h
>> @@ -378,7 +378,7 @@ struct xfs_bulkstat {
>> uint32_t bs_extsize_blks; /* extent size hint, blocks */
>>
>> uint32_t bs_nlink; /* number of links */
>> - uint32_t bs_extents; /* number of extents */
>> + uint32_t bs_extents; /* 32-bit data fork extent counter */
>> uint32_t bs_aextents; /* attribute number of extents */
>> uint16_t bs_version; /* structure version */
>> uint16_t bs_forkoff; /* inode fork offset in bytes */
>> @@ -387,8 +387,9 @@ struct xfs_bulkstat {
>> uint16_t bs_checked; /* checked inode metadata */
>> uint16_t bs_mode; /* type and mode */
>> uint16_t bs_pad2; /* zeroed */
>> + uint64_t bs_extents64; /* 64-bit data fork extent counter */
>>
>> - uint64_t bs_pad[7]; /* zeroed */
>> + uint64_t bs_pad[6]; /* zeroed */
>> };
>>
>> #define XFS_BULKSTAT_VERSION_V1 (1)
>> @@ -469,8 +470,19 @@ struct xfs_bulk_ireq {
>> */
>> #define XFS_BULK_IREQ_SPECIAL (1 << 1)
>>
>> -#define XFS_BULK_IREQ_FLAGS_ALL (XFS_BULK_IREQ_AGNO | \
>> - XFS_BULK_IREQ_SPECIAL)
>> +/*
>> + * Return data fork extent count via xfs_bulkstat->bs_extents64 field and assign
>> + * 0 to xfs_bulkstat->bs_extents when the flag is set. Otherwise, use
>> + * xfs_bulkstat->bs_extents for returning data fork extent count and set
>> + * xfs_bulkstat->bs_extents64 to 0. In the second case, return -EOVERFLOW and
>> + * assign 0 to xfs_bulkstat->bs_extents if data fork extent count is larger than
>> + * XFS_MAX_EXTCNT_DATA_FORK_OLD.
>> + */
>> +#define XFS_BULK_IREQ_NREXT64 (1 << 2)
>> +
>> +#define XFS_BULK_IREQ_FLAGS_ALL (XFS_BULK_IREQ_AGNO | \
>> + XFS_BULK_IREQ_SPECIAL | \
>> + XFS_BULK_IREQ_NREXT64)
>>
>> /* Operate on the root directory inode. */
>> #define XFS_BULK_IREQ_SPECIAL_ROOT (1)
>> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
>> index 83481005317a..e9eadc7337ce 100644
>> --- a/fs/xfs/xfs_ioctl.c
>> +++ b/fs/xfs/xfs_ioctl.c
>> @@ -813,6 +813,9 @@ xfs_bulk_ireq_setup(
>> if (XFS_INO_TO_AGNO(mp, breq->startino) >= mp->m_sb.sb_agcount)
>> return -ECANCELED;
>>
>> + if (hdr->flags & XFS_BULK_IREQ_NREXT64)
>> + breq->flags |= XFS_IBULK_NREXT64;
>> +
>> return 0;
>> }
>>
>> diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
>> index 71ed4905f206..847f03f75a38 100644
>> --- a/fs/xfs/xfs_itable.c
>> +++ b/fs/xfs/xfs_itable.c
>> @@ -64,6 +64,7 @@ xfs_bulkstat_one_int(
>> struct xfs_inode *ip; /* incore inode pointer */
>> struct inode *inode;
>> struct xfs_bulkstat *buf = bc->buf;
>> + xfs_extnum_t nextents;
>> int error = -EINVAL;
>>
>> if (xfs_internal_inum(mp, ino))
>> @@ -102,7 +103,17 @@ xfs_bulkstat_one_int(
>>
>> buf->bs_xflags = xfs_ip2xflags(ip);
>> buf->bs_extsize_blks = ip->i_extsize;
>> - buf->bs_extents = xfs_ifork_nextents(&ip->i_df);
>> +
>> + nextents = xfs_ifork_nextents(&ip->i_df);
>> + if (!(bc->breq->flags & XFS_IBULK_NREXT64)) {
>> + if (nextents > XFS_MAX_EXTCNT_DATA_FORK_SMALL)
>> + buf->bs_extents = XFS_MAX_EXTCNT_DATA_FORK_SMALL;
>> + else
>> + buf->bs_extents = nextents;
>
> buf->bs_extents = min(nextents, XFS_MAX_EXTCNT_DATA_FORK_SMALL); ?
>

This is much cleaner. I will apply the above suggestion.

>> + } else {
>> + buf->bs_extents64 = nextents;
>> + }
>> +
>> xfs_bulkstat_health(ip, buf);
>> buf->bs_aextents = xfs_ifork_nextents(ip->i_afp);
>> buf->bs_forkoff = XFS_IFORK_BOFF(ip);
>> diff --git a/fs/xfs/xfs_itable.h b/fs/xfs/xfs_itable.h
>> index 2cf3872fcd2f..0150fd53d18e 100644
>> --- a/fs/xfs/xfs_itable.h
>> +++ b/fs/xfs/xfs_itable.h
>> @@ -19,6 +19,8 @@ struct xfs_ibulk {
>> /* Only iterate within the same AG as startino */
>> #define XFS_IBULK_SAME_AG (1 << 0)
>>
>> +#define XFS_IBULK_NREXT64 (1 << 1)
>
> Needs a comment here.
>
> /* Fill out the bs_extents64 field if set. */
> #define XFS_IBULK_NREXT64 (1U << 1)
>
> (Are we supposed to do "1U" now?)
>

I will apply the above suggestion.

--
chandan