Re: [PATCH 07/13] xfs: refactor common transaction/inode/quota allocation idiom

Brian Foster
2021-01-28T18:27:10Z

On Wed, Jan 27, 2021 at 10:01:44PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@kernel.org>
>
> Create a new helper xfs_trans_alloc_inode that allocates a transaction,
> locks and joins an inode to it, and then reserves the appropriate amount
> of quota against that transction. Then replace all the open-coded
> idioms with a single call to this helper.
>
> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> ---

Reviewed-by: Brian Foster <bfoster@redhat.com>

> fs/xfs/libxfs/xfs_attr.c | 11 +----------
> fs/xfs/libxfs/xfs_bmap.c | 10 ++--------
> fs/xfs/xfs_bmap_util.c | 14 +++----------
> fs/xfs/xfs_iomap.c | 11 ++---------
> fs/xfs/xfs_trans.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++
> fs/xfs/xfs_trans.h | 3 +++
> 6 files changed, 59 insertions(+), 38 deletions(-)
>
>
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index e05dc0bc4a8f..cb95bc77fe59 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -458,14 +458,10 @@ xfs_attr_set(
> * Root fork attributes can use reserved data blocks for this
> * operation if necessary
> */
> - error = xfs_trans_alloc(mp, &tres, total, 0,
> - rsvd ? XFS_TRANS_RESERVE : 0, &args->trans);
> + error = xfs_trans_alloc_inode(dp, &tres, total, rsvd, &args->trans);
> if (error)
> return error;
>
> - xfs_ilock(dp, XFS_ILOCK_EXCL);
> - xfs_trans_ijoin(args->trans, dp, 0);
> -
> if (args->value || xfs_inode_hasattr(dp)) {
> error = xfs_iext_count_may_overflow(dp, XFS_ATTR_FORK,
> XFS_IEXT_ATTR_MANIP_CNT(rmt_blks));
> @@ -474,11 +470,6 @@ xfs_attr_set(
> }
>
> if (args->value) {
> - error = xfs_trans_reserve_quota_nblks(args->trans, dp,
> - args->total, 0, rsvd);
> - if (error)
> - goto out_trans_cancel;
> -
> error = xfs_has_attr(args);
> if (error == -EEXIST && (args->attr_flags & XATTR_CREATE))
> goto out_trans_cancel;
> diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
> index 043bb8c634b0..f78fa694f3c2 100644
> --- a/fs/xfs/libxfs/xfs_bmap.c
> +++ b/fs/xfs/libxfs/xfs_bmap.c
> @@ -1079,19 +1079,13 @@ xfs_bmap_add_attrfork(
>
> blks = XFS_ADDAFORK_SPACE_RES(mp);
>
> - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_addafork, blks, 0,
> - rsvd ? XFS_TRANS_RESERVE : 0, &tp);
> + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_addafork, blks,
> + rsvd, &tp);
> if (error)
> return error;
> -
> - xfs_ilock(ip, XFS_ILOCK_EXCL);
> - error = xfs_trans_reserve_quota_nblks(tp, ip, blks, 0, rsvd);
> - if (error)
> - goto trans_cancel;
> if (XFS_IFORK_Q(ip))
> goto trans_cancel;
>
> - xfs_trans_ijoin(tp, ip, 0);
> xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
> error = xfs_bmap_set_attrforkoff(ip, size, &version);
> if (error)
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index d54d9f02d3dd..94ffdeb2dd73 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -873,18 +873,10 @@ xfs_unmap_extent(
> uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
> int error;
>
> - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
> - if (error) {
> - ASSERT(error == -ENOSPC || XFS_FORCED_SHUTDOWN(mp));
> - return error;
> - }
> -
> - xfs_ilock(ip, XFS_ILOCK_EXCL);
> - error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0, false);
> + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks,
> + false, &tp);
> if (error)
> - goto out_trans_cancel;
> -
> - xfs_trans_ijoin(tp, ip, 0);
> + return error;
>
> error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK,
> XFS_IEXT_PUNCH_HOLE_CNT);
> diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
> index ef29d44c656a..05de1be20426 100644
> --- a/fs/xfs/xfs_iomap.c
> +++ b/fs/xfs/xfs_iomap.c
> @@ -552,18 +552,11 @@ xfs_iomap_write_unwritten(
> * here as we might be asked to write out the same inode that we
> * complete here and might deadlock on the iolock.
> */
> - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
> - XFS_TRANS_RESERVE, &tp);
> + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks,
> + true, &tp);
> if (error)
> return error;
>
> - xfs_ilock(ip, XFS_ILOCK_EXCL);
> - xfs_trans_ijoin(tp, ip, 0);
> -
> - error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0, true);
> - if (error)
> - goto error_on_bmapi_transaction;
> -
> error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK,
> XFS_IEXT_WRITE_UNWRITTEN_CNT);
> if (error)
> diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
> index e72730f85af1..156b9ed8534f 100644
> --- a/fs/xfs/xfs_trans.c
> +++ b/fs/xfs/xfs_trans.c
> @@ -20,6 +20,7 @@
> #include "xfs_trace.h"
> #include "xfs_error.h"
> #include "xfs_defer.h"
> +#include "xfs_inode.h"
>
> kmem_zone_t *xfs_trans_zone;
>
> @@ -1024,3 +1025,50 @@ xfs_trans_roll(
> tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
> return xfs_trans_reserve(*tpp, &tres, 0, 0);
> }
> +
> +/*
> + * Allocate an transaction, lock and join the inode to it, and reserve quota.
> + *
> + * The caller must ensure that the on-disk dquots attached to this inode have
> + * already been allocated and initialized. The caller is responsible for
> + * releasing ILOCK_EXCL if a new transaction is returned.
> + */
> +int
> +xfs_trans_alloc_inode(
> + struct xfs_inode *ip,
> + struct xfs_trans_res *resv,
> + unsigned int dblocks,
> + bool force,
> + struct xfs_trans **tpp)
> +{
> + struct xfs_trans *tp;
> + struct xfs_mount *mp = ip->i_mount;
> + int error;
> +
> + error = xfs_trans_alloc(mp, resv, dblocks, 0,
> + force ? XFS_TRANS_RESERVE : 0, &tp);
> + if (error)
> + return error;
> +
> + xfs_ilock(ip, XFS_ILOCK_EXCL);
> + xfs_trans_ijoin(tp, ip, 0);
> +
> + error = xfs_qm_dqattach_locked(ip, false);
> + if (error) {
> + /* Caller should have allocated the dquots! */
> + ASSERT(error != -ENOENT);
> + goto out_cancel;
> + }
> +
> + error = xfs_trans_reserve_quota_nblks(tp, ip, dblocks, 0, force);
> + if (error)
> + goto out_cancel;
> +
> + *tpp = tp;
> + return 0;
> +
> +out_cancel:
> + xfs_trans_cancel(tp);
> + xfs_iunlock(ip, XFS_ILOCK_EXCL);
> + return error;
> +}
> diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
> index 084658946cc8..aa50be244432 100644
> --- a/fs/xfs/xfs_trans.h
> +++ b/fs/xfs/xfs_trans.h
> @@ -268,4 +268,7 @@ xfs_trans_item_relog(
> return lip->li_ops->iop_relog(lip, tp);
> }
>
> +int xfs_trans_alloc_inode(struct xfs_inode *ip, struct xfs_trans_res *resv,
> + unsigned int dblocks, bool force, struct xfs_trans **tpp);
> +
> #endif /* __XFS_TRANS_H__ */
>