xfs: move lru refs to the btree ops structure

Move the btree buffer LRU refcount to the btree ops structure so that we
can eliminate the last bc_btnum switch in the generic btree code.  We're
about to create repair-specific btree types, and we don't want that
stuff cluttering up libxfs.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/libxfs/xfs_alloc_btree.c

@@ -458,6 +458,8 @@ const struct xfs_btree_ops xfs_bnobt_ops = {
 	.rec_len		= sizeof(xfs_alloc_rec_t),
 	.key_len		= sizeof(xfs_alloc_key_t),
 
+	.lru_refs		= XFS_ALLOC_BTREE_REF,
+
 	.dup_cursor		= xfs_allocbt_dup_cursor,
 	.set_root		= xfs_allocbt_set_root,
 	.alloc_block		= xfs_allocbt_alloc_block,
@@ -483,6 +485,8 @@ const struct xfs_btree_ops xfs_cntbt_ops = {
 	.rec_len		= sizeof(xfs_alloc_rec_t),
 	.key_len		= sizeof(xfs_alloc_key_t),
 
+	.lru_refs		= XFS_ALLOC_BTREE_REF,
+
 	.dup_cursor		= xfs_allocbt_dup_cursor,
 	.set_root		= xfs_allocbt_set_root,
 	.alloc_block		= xfs_allocbt_alloc_block,

fs/xfs/libxfs/xfs_bmap_btree.c

@@ -530,6 +530,8 @@ const struct xfs_btree_ops xfs_bmbt_ops = {
 	.rec_len		= sizeof(xfs_bmbt_rec_t),
 	.key_len		= sizeof(xfs_bmbt_key_t),
 
+	.lru_refs		= XFS_BMAP_BTREE_REF,
+
 	.dup_cursor		= xfs_bmbt_dup_cursor,
 	.update_cursor		= xfs_bmbt_update_cursor,
 	.alloc_block		= xfs_bmbt_alloc_block,

fs/xfs/libxfs/xfs_btree.c

@@ -1284,32 +1284,12 @@ xfs_btree_buf_to_ptr(
 	}
 }
 
-STATIC void
+static inline void
 xfs_btree_set_refs(
 	struct xfs_btree_cur	*cur,
 	struct xfs_buf		*bp)
 {
-	switch (cur->bc_btnum) {
-	case XFS_BTNUM_BNO:
-	case XFS_BTNUM_CNT:
-		xfs_buf_set_ref(bp, XFS_ALLOC_BTREE_REF);
-		break;
-	case XFS_BTNUM_INO:
-	case XFS_BTNUM_FINO:
-		xfs_buf_set_ref(bp, XFS_INO_BTREE_REF);
-		break;
-	case XFS_BTNUM_BMAP:
-		xfs_buf_set_ref(bp, XFS_BMAP_BTREE_REF);
-		break;
-	case XFS_BTNUM_RMAP:
-		xfs_buf_set_ref(bp, XFS_RMAP_BTREE_REF);
-		break;
-	case XFS_BTNUM_REFC:
-		xfs_buf_set_ref(bp, XFS_REFC_BTREE_REF);
-		break;
-	default:
-		ASSERT(0);
-	}
+	xfs_buf_set_ref(bp, cur->bc_ops->lru_refs);
 }
 
 int

fs/xfs/libxfs/xfs_btree.h

@@ -120,6 +120,9 @@ struct xfs_btree_ops {
 	size_t	key_len;
 	size_t	rec_len;
 
+	/* LRU refcount to set on each btree buffer created */
+	unsigned int		lru_refs;
+
 	/* cursor operations */
 	struct xfs_btree_cur *(*dup_cursor)(struct xfs_btree_cur *);
 	void	(*update_cursor)(struct xfs_btree_cur *src,

fs/xfs/libxfs/xfs_ialloc_btree.c

@@ -402,6 +402,8 @@ const struct xfs_btree_ops xfs_inobt_ops = {
 	.rec_len		= sizeof(xfs_inobt_rec_t),
 	.key_len		= sizeof(xfs_inobt_key_t),
 
+	.lru_refs		= XFS_INO_BTREE_REF,
+
 	.dup_cursor		= xfs_inobt_dup_cursor,
 	.set_root		= xfs_inobt_set_root,
 	.alloc_block		= xfs_inobt_alloc_block,
@@ -424,6 +426,8 @@ const struct xfs_btree_ops xfs_finobt_ops = {
 	.rec_len		= sizeof(xfs_inobt_rec_t),
 	.key_len		= sizeof(xfs_inobt_key_t),
 
+	.lru_refs		= XFS_INO_BTREE_REF,
+
 	.dup_cursor		= xfs_inobt_dup_cursor,
 	.set_root		= xfs_finobt_set_root,
 	.alloc_block		= xfs_finobt_alloc_block,

fs/xfs/libxfs/xfs_refcount_btree.c

@@ -321,6 +321,8 @@ const struct xfs_btree_ops xfs_refcountbt_ops = {
 	.rec_len		= sizeof(struct xfs_refcount_rec),
 	.key_len		= sizeof(struct xfs_refcount_key),
 
+	.lru_refs		= XFS_REFC_BTREE_REF,
+
 	.dup_cursor		= xfs_refcountbt_dup_cursor,
 	.set_root		= xfs_refcountbt_set_root,
 	.alloc_block		= xfs_refcountbt_alloc_block,

fs/xfs/libxfs/xfs_rmap_btree.c

@@ -478,6 +478,8 @@ const struct xfs_btree_ops xfs_rmapbt_ops = {
 	.rec_len		= sizeof(struct xfs_rmap_rec),
 	.key_len		= 2 * sizeof(struct xfs_rmap_key),
 
+	.lru_refs		= XFS_RMAP_BTREE_REF,
+
 	.dup_cursor		= xfs_rmapbt_dup_cursor,
 	.set_root		= xfs_rmapbt_set_root,
 	.alloc_block		= xfs_rmapbt_alloc_block,