xfs: refactor recovery transaction start handling

Rework the transaction lookup and allocation code in
xlog_recovery_process_ophdr() to fold two related call-once
helper functions into a single helper. Then fold in all the
XLOG_START_TRANS logic to that helper to clean up the remaining
logic in xlog_recovery_process_ophdr().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 files changed, 34 insertions, 43 deletions

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 6af9e1a74155..5019f52e4cc2 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -3353,38 +3353,6 @@ out:
         return error ? error : error2;
 }
 
-
-STATIC xlog_recover_t *
-xlog_recover_find_tid(
-        struct hlist_head       *head,
-        xlog_tid_t              tid)
-{
-        xlog_recover_t          *trans;
-
-        hlist_for_each_entry(trans, head, r_list) {
-                if (trans->r_log_tid == tid)
-                        return trans;
-        }
-        return NULL;
-}
-
-STATIC void
-xlog_recover_new_tid(
-        struct hlist_head       *head,
-        xlog_tid_t              tid,
-        xfs_lsn_t               lsn)
-{
-        xlog_recover_t          *trans;
-
-        trans = kmem_zalloc(sizeof(xlog_recover_t), KM_SLEEP);
-        trans->r_log_tid   = tid;
-        trans->r_lsn       = lsn;
-        INIT_LIST_HEAD(&trans->r_itemq);
-
-        INIT_HLIST_NODE(&trans->r_list);
-        hlist_add_head(&trans->r_list, head);
-}
-
 STATIC void
 xlog_recover_add_item(
         struct list_head        *head)
@@ -3507,6 +3475,7 @@ xlog_recover_add_to_trans(
         trace_xfs_log_recover_item_add(log, trans, item, 0);
         return 0;
 }
+
 /*
  * Free up any resources allocated by the transaction
  *
@@ -3589,6 +3558,13 @@ xlog_recovery_process_trans(
         return error;
 }
 
+/*
+ * Lookup the transaction recovery structure associated with the ID in the
+ * current ophdr. If the transaction doesn't exist and the start flag is set in
+ * the ophdr, then allocate a new transaction for future ID matches to find.
+ * Either way, return what we found during the lookup - an existing transaction
+ * or nothing.
+ */
 STATIC struct xlog_recover *
 xlog_recover_ophdr_to_trans(
         struct hlist_head       rhash[],
@@ -3601,20 +3577,35 @@ xlog_recover_ophdr_to_trans(
 
         tid = be32_to_cpu(ohead->oh_tid);
         rhp = &rhash[XLOG_RHASH(tid)];
-        trans = xlog_recover_find_tid(rhp, tid);
-        if (trans)
-                return trans;
+        hlist_for_each_entry(trans, rhp, r_list) {
+                if (trans->r_log_tid == tid)
+                        return trans;
+        }
 
         /*
-         * If this is a new transaction, the ophdr only contains the
-         * start record. In that case, the only processing we need to do
-         * on this opheader is allocate a new recovery container to hold
-         * the recovery ops that will follow.
+         * skip over non-start transaction headers - we could be
+         * processing slack space before the next transaction starts
+         */
+        if (!(ohead->oh_flags & XLOG_START_TRANS))
+                return NULL;
+
+        ASSERT(be32_to_cpu(ohead->oh_len) == 0);
+
+        /*
+         * This is a new transaction so allocate a new recovery container to
+         * hold the recovery ops that will follow.
+         */
+        trans = kmem_zalloc(sizeof(struct xlog_recover), KM_SLEEP);
+        trans->r_log_tid = tid;
+        trans->r_lsn = be64_to_cpu(rhead->h_lsn);
+        INIT_LIST_HEAD(&trans->r_itemq);
+        INIT_HLIST_NODE(&trans->r_list);
+        hlist_add_head(&trans->r_list, rhp);
+
+        /*
+         * Nothing more to do for this ophdr. Items to be added to this new
+         * transaction will be in subsequent ophdr containers.
          */
-        if (ohead->oh_flags & XLOG_START_TRANS) {
-                ASSERT(be32_to_cpu(ohead->oh_len) == 0);
-                xlog_recover_new_tid(rhp, tid, be64_to_cpu(rhead->h_lsn));
-        }
         return NULL;
 }