xfs: implement deferred bmbt map/unmap operations
Implement deferred versions of the inode block map/unmap functions.
These will be used in subsequent patches to make reflink operations
atomic.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/xfs/xfs_trans_bmap.c b/fs/xfs/xfs_trans_bmap.c
index 656d669..6408e7d 100644
--- a/fs/xfs/xfs_trans_bmap.c
+++ b/fs/xfs/xfs_trans_bmap.c
@@ -68,7 +68,8 @@
{
int error;
- error = -EFSCORRUPTED;
+ error = xfs_bmap_finish_one(tp, dop, ip, type, whichfork, startoff,
+ startblock, blockcount, state);
/*
* Mark the transaction dirty, even on error. This ensures the
@@ -82,3 +83,167 @@
return error;
}
+
+/* Sort bmap intents by inode. */
+static int
+xfs_bmap_update_diff_items(
+ void *priv,
+ struct list_head *a,
+ struct list_head *b)
+{
+ struct xfs_bmap_intent *ba;
+ struct xfs_bmap_intent *bb;
+
+ ba = container_of(a, struct xfs_bmap_intent, bi_list);
+ bb = container_of(b, struct xfs_bmap_intent, bi_list);
+ return ba->bi_owner->i_ino - bb->bi_owner->i_ino;
+}
+
+/* Get an BUI. */
+STATIC void *
+xfs_bmap_update_create_intent(
+ struct xfs_trans *tp,
+ unsigned int count)
+{
+ struct xfs_bui_log_item *buip;
+
+ ASSERT(count == XFS_BUI_MAX_FAST_EXTENTS);
+ ASSERT(tp != NULL);
+
+ buip = xfs_bui_init(tp->t_mountp);
+ ASSERT(buip != NULL);
+
+ /*
+ * Get a log_item_desc to point at the new item.
+ */
+ xfs_trans_add_item(tp, &buip->bui_item);
+ return buip;
+}
+
+/* Set the map extent flags for this mapping. */
+static void
+xfs_trans_set_bmap_flags(
+ struct xfs_map_extent *bmap,
+ enum xfs_bmap_intent_type type,
+ int whichfork,
+ xfs_exntst_t state)
+{
+ bmap->me_flags = 0;
+ switch (type) {
+ case XFS_BMAP_MAP:
+ case XFS_BMAP_UNMAP:
+ bmap->me_flags = type;
+ break;
+ default:
+ ASSERT(0);
+ }
+ if (state == XFS_EXT_UNWRITTEN)
+ bmap->me_flags |= XFS_BMAP_EXTENT_UNWRITTEN;
+ if (whichfork == XFS_ATTR_FORK)
+ bmap->me_flags |= XFS_BMAP_EXTENT_ATTR_FORK;
+}
+
+/* Log bmap updates in the intent item. */
+STATIC void
+xfs_bmap_update_log_item(
+ struct xfs_trans *tp,
+ void *intent,
+ struct list_head *item)
+{
+ struct xfs_bui_log_item *buip = intent;
+ struct xfs_bmap_intent *bmap;
+ uint next_extent;
+ struct xfs_map_extent *map;
+
+ bmap = container_of(item, struct xfs_bmap_intent, bi_list);
+
+ tp->t_flags |= XFS_TRANS_DIRTY;
+ buip->bui_item.li_desc->lid_flags |= XFS_LID_DIRTY;
+
+ /*
+ * atomic_inc_return gives us the value after the increment;
+ * we want to use it as an array index so we need to subtract 1 from
+ * it.
+ */
+ next_extent = atomic_inc_return(&buip->bui_next_extent) - 1;
+ ASSERT(next_extent < buip->bui_format.bui_nextents);
+ map = &buip->bui_format.bui_extents[next_extent];
+ map->me_owner = bmap->bi_owner->i_ino;
+ map->me_startblock = bmap->bi_bmap.br_startblock;
+ map->me_startoff = bmap->bi_bmap.br_startoff;
+ map->me_len = bmap->bi_bmap.br_blockcount;
+ xfs_trans_set_bmap_flags(map, bmap->bi_type, bmap->bi_whichfork,
+ bmap->bi_bmap.br_state);
+}
+
+/* Get an BUD so we can process all the deferred rmap updates. */
+STATIC void *
+xfs_bmap_update_create_done(
+ struct xfs_trans *tp,
+ void *intent,
+ unsigned int count)
+{
+ return xfs_trans_get_bud(tp, intent);
+}
+
+/* Process a deferred rmap update. */
+STATIC int
+xfs_bmap_update_finish_item(
+ struct xfs_trans *tp,
+ struct xfs_defer_ops *dop,
+ struct list_head *item,
+ void *done_item,
+ void **state)
+{
+ struct xfs_bmap_intent *bmap;
+ int error;
+
+ bmap = container_of(item, struct xfs_bmap_intent, bi_list);
+ error = xfs_trans_log_finish_bmap_update(tp, done_item, dop,
+ bmap->bi_type,
+ bmap->bi_owner, bmap->bi_whichfork,
+ bmap->bi_bmap.br_startoff,
+ bmap->bi_bmap.br_startblock,
+ bmap->bi_bmap.br_blockcount,
+ bmap->bi_bmap.br_state);
+ kmem_free(bmap);
+ return error;
+}
+
+/* Abort all pending BUIs. */
+STATIC void
+xfs_bmap_update_abort_intent(
+ void *intent)
+{
+ xfs_bui_release(intent);
+}
+
+/* Cancel a deferred rmap update. */
+STATIC void
+xfs_bmap_update_cancel_item(
+ struct list_head *item)
+{
+ struct xfs_bmap_intent *bmap;
+
+ bmap = container_of(item, struct xfs_bmap_intent, bi_list);
+ kmem_free(bmap);
+}
+
+static const struct xfs_defer_op_type xfs_bmap_update_defer_type = {
+ .type = XFS_DEFER_OPS_TYPE_BMAP,
+ .max_items = XFS_BUI_MAX_FAST_EXTENTS,
+ .diff_items = xfs_bmap_update_diff_items,
+ .create_intent = xfs_bmap_update_create_intent,
+ .abort_intent = xfs_bmap_update_abort_intent,
+ .log_item = xfs_bmap_update_log_item,
+ .create_done = xfs_bmap_update_create_done,
+ .finish_item = xfs_bmap_update_finish_item,
+ .cancel_item = xfs_bmap_update_cancel_item,
+};
+
+/* Register the deferred op type. */
+void
+xfs_bmap_update_init_defer_op(void)
+{
+ xfs_defer_init_op_type(&xfs_bmap_update_defer_type);
+}