xfs: add firstblock field to xfs_trans

A firstblock var is typically allocated and initialized along with
xfs_defer_ops structures and passed around independent from the
associated transaction. To facilitate combining the two, add an
optional ->t_firstblock field to xfs_trans that can be used in place
of an on-stack variable.

The firstblock value follows the lifetime of the transaction, so
initialize it on allocation and when a transaction rolls.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index 6309933..de00f79 100644 (file)
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -100,6 +100,7 @@ xfs_trans_dup(
        ntp->t_mountp = tp->t_mountp;
        INIT_LIST_HEAD(&ntp->t_items);
        INIT_LIST_HEAD(&ntp->t_busy);
+       ntp->t_firstblock = NULLFSBLOCK;
 
        ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
        ASSERT(tp->t_ticket != NULL);
@@ -273,6 +274,7 @@ xfs_trans_alloc(
        tp->t_mountp = mp;
        INIT_LIST_HEAD(&tp->t_items);
        INIT_LIST_HEAD(&tp->t_busy);
+       tp->t_firstblock = NULLFSBLOCK;
 
        error = xfs_trans_reserve(tp, resp, blocks, rtextents);
        if (error) {

diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index d8a695c..37fdacc 100644 (file)
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -102,6 +102,7 @@ typedef struct xfs_trans {
        unsigned int            t_blk_res_used; /* # of resvd blocks used */
        unsigned int            t_rtx_res;      /* # of rt extents resvd */
        unsigned int            t_rtx_res_used; /* # of resvd rt extents used */
+       xfs_fsblock_t           t_firstblock;   /* first block allocated */
        struct xlog_ticket      *t_ticket;      /* log mgr ticket */
        struct xfs_mount        *t_mountp;      /* ptr to fs mount struct */
        struct xfs_dquot_acct   *t_dqinfo;      /* acctg info for dquots */