ocfs2: Modify removing xattr process for refcount.

The old xattr value remove is quite simple, it just erase the
tree and free the clusters. But as we have added refcount support,
The process is a little complicated.

We have to lock the refcount tree at the beginning, what's more,
we may split the refcount tree in some cases, so meta/credits are
needed.

Signed-off-by: Tao Ma <tao.ma@oracle.com>

fs/ocfs2/xattr.c

@@ -199,6 +199,11 @@ static int ocfs2_prepare_refcount_xattr(struct inode *inode,
 					struct ocfs2_refcount_tree **ref_tree,
 					int *meta_need,
 					int *credits);
+static int ocfs2_get_xattr_tree_value_root(struct super_block *sb,
+					   struct ocfs2_xattr_bucket *bucket,
+					   int offset,
+					   struct ocfs2_xattr_value_root **xv,
+					   struct buffer_head **bh);
 
 static inline u16 ocfs2_xattr_buckets_per_cluster(struct ocfs2_super *osb)
 {
@@ -1752,51 +1757,112 @@ out:
 	return ret;
 }
 
+/*
+ * In xattr remove, if it is stored outside and refcounted, we may have
+ * the chance to split the refcount tree. So need the allocators.
+ */
+static int ocfs2_lock_xattr_remove_allocators(struct inode *inode,
+					struct ocfs2_xattr_value_root *xv,
+					struct ocfs2_caching_info *ref_ci,
+					struct buffer_head *ref_root_bh,
+					struct ocfs2_alloc_context **meta_ac,
+					int *ref_credits)
+{
+	int ret, meta_add = 0;
+	u32 p_cluster, num_clusters;
+	unsigned int ext_flags;
+
+	*ref_credits = 0;
+	ret = ocfs2_xattr_get_clusters(inode, 0, &p_cluster,
+				       &num_clusters,
+				       &xv->xr_list,
+				       &ext_flags);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	if (!(ext_flags & OCFS2_EXT_REFCOUNTED))
+		goto out;
+
+	ret = ocfs2_refcounted_xattr_delete_need(inode, ref_ci,
+						 ref_root_bh, xv,
+						 &meta_add, ref_credits);
+	if (ret) {
+		mlog_errno(ret);
+		goto out;
+	}
+
+	ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(inode->i_sb),
+						meta_add, meta_ac);
+	if (ret)
+		mlog_errno(ret);
+
+out:
+	return ret;
+}
+
 static int ocfs2_remove_value_outside(struct inode*inode,
 				      struct ocfs2_xattr_value_buf *vb,
-				      struct ocfs2_xattr_header *header)
+				      struct ocfs2_xattr_header *header,
+				      struct ocfs2_caching_info *ref_ci,
+				      struct buffer_head *ref_root_bh)
 {
-	int ret = 0, i;
+	int ret = 0, i, ref_credits;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	struct ocfs2_xattr_set_ctxt ctxt = { NULL, NULL, };
+	void *val;
 
 	ocfs2_init_dealloc_ctxt(&ctxt.dealloc);
 
-	ctxt.handle = ocfs2_start_trans(osb,
-					ocfs2_remove_extent_credits(osb->sb));
-	if (IS_ERR(ctxt.handle)) {
-		ret = PTR_ERR(ctxt.handle);
-		mlog_errno(ret);
-		goto out;
-	}
-
 	for (i = 0; i < le16_to_cpu(header->xh_count); i++) {
 		struct ocfs2_xattr_entry *entry = &header->xh_entries[i];
 
-		if (!ocfs2_xattr_is_local(entry)) {
-			void *val;
+		if (ocfs2_xattr_is_local(entry))
+			continue;
 
-			val = (void *)header +
-				le16_to_cpu(entry->xe_name_offset);
-			vb->vb_xv = (struct ocfs2_xattr_value_root *)
-				(val + OCFS2_XATTR_SIZE(entry->xe_name_len));
-			ret = ocfs2_xattr_value_truncate(inode, vb, 0, &ctxt);
-			if (ret < 0) {
-				mlog_errno(ret);
-				break;
-			}
+		val = (void *)header +
+			le16_to_cpu(entry->xe_name_offset);
+		vb->vb_xv = (struct ocfs2_xattr_value_root *)
+			(val + OCFS2_XATTR_SIZE(entry->xe_name_len));
+
+		ret = ocfs2_lock_xattr_remove_allocators(inode, vb->vb_xv,
+							 ref_ci, ref_root_bh,
+							 &ctxt.meta_ac,
+							 &ref_credits);
+
+		ctxt.handle = ocfs2_start_trans(osb, ref_credits +
+					ocfs2_remove_extent_credits(osb->sb));
+		if (IS_ERR(ctxt.handle)) {
+			ret = PTR_ERR(ctxt.handle);
+			mlog_errno(ret);
+			break;
+		}
+
+		ret = ocfs2_xattr_value_truncate(inode, vb, 0, &ctxt);
+		if (ret < 0) {
+			mlog_errno(ret);
+			break;
+		}
+
+		ocfs2_commit_trans(osb, ctxt.handle);
+		if (ctxt.meta_ac) {
+			ocfs2_free_alloc_context(ctxt.meta_ac);
+			ctxt.meta_ac = NULL;
 		}
 	}
 
-	ocfs2_commit_trans(osb, ctxt.handle);
+	if (ctxt.meta_ac)
+		ocfs2_free_alloc_context(ctxt.meta_ac);
 	ocfs2_schedule_truncate_log_flush(osb, 1);
 	ocfs2_run_deallocs(osb, &ctxt.dealloc);
-out:
 	return ret;
 }
 
 static int ocfs2_xattr_ibody_remove(struct inode *inode,
-				    struct buffer_head *di_bh)
+				    struct buffer_head *di_bh,
+				    struct ocfs2_caching_info *ref_ci,
+				    struct buffer_head *ref_root_bh)
 {
 
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
@@ -1811,13 +1877,21 @@ static int ocfs2_xattr_ibody_remove(struct inode *inode,
 		 ((void *)di + inode->i_sb->s_blocksize -
 		 le16_to_cpu(di->i_xattr_inline_size));
 
-	ret = ocfs2_remove_value_outside(inode, &vb, header);
+	ret = ocfs2_remove_value_outside(inode, &vb, header,
+					 ref_ci, ref_root_bh);
 
 	return ret;
 }
 
+struct ocfs2_rm_xattr_bucket_para {
+	struct ocfs2_caching_info *ref_ci;
+	struct buffer_head *ref_root_bh;
+};
+
 static int ocfs2_xattr_block_remove(struct inode *inode,
-				    struct buffer_head *blk_bh)
+				    struct buffer_head *blk_bh,
+				    struct ocfs2_caching_info *ref_ci,
+				    struct buffer_head *ref_root_bh)
 {
 	struct ocfs2_xattr_block *xb;
 	int ret = 0;
@@ -1825,22 +1899,29 @@ static int ocfs2_xattr_block_remove(struct inode *inode,
 		.vb_bh = blk_bh,
 		.vb_access = ocfs2_journal_access_xb,
 	};
+	struct ocfs2_rm_xattr_bucket_para args = {
+		.ref_ci = ref_ci,
+		.ref_root_bh = ref_root_bh,
+	};
 
 	xb = (struct ocfs2_xattr_block *)blk_bh->b_data;
 	if (!(le16_to_cpu(xb->xb_flags) & OCFS2_XATTR_INDEXED)) {
 		struct ocfs2_xattr_header *header = &(xb->xb_attrs.xb_header);
-		ret = ocfs2_remove_value_outside(inode, &vb, header);
+		ret = ocfs2_remove_value_outside(inode, &vb, header,
+						 ref_ci, ref_root_bh);
 	} else
 		ret = ocfs2_iterate_xattr_index_block(inode,
 						blk_bh,
 						ocfs2_rm_xattr_cluster,
-						NULL);
+						&args);
 
 	return ret;
 }
 
 static int ocfs2_xattr_free_block(struct inode *inode,
-				  u64 block)
+				  u64 block,
+				  struct ocfs2_caching_info *ref_ci,
+				  struct buffer_head *ref_root_bh)
 {
 	struct inode *xb_alloc_inode;
 	struct buffer_head *xb_alloc_bh = NULL;
@@ -1858,7 +1939,7 @@ static int ocfs2_xattr_free_block(struct inode *inode,
 		goto out;
 	}
 
-	ret = ocfs2_xattr_block_remove(inode, blk_bh);
+	ret = ocfs2_xattr_block_remove(inode, blk_bh, ref_ci, ref_root_bh);
 	if (ret < 0) {
 		mlog_errno(ret);
 		goto out;
@@ -1918,6 +1999,9 @@ int ocfs2_xattr_remove(struct inode *inode, struct buffer_head *di_bh)
 {
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
+	struct ocfs2_refcount_tree *ref_tree = NULL;
+	struct buffer_head *ref_root_bh = NULL;
+	struct ocfs2_caching_info *ref_ci = NULL;
 	handle_t *handle;
 	int ret;
 
@@ -1927,8 +2011,21 @@ int ocfs2_xattr_remove(struct inode *inode, struct buffer_head *di_bh)
 	if (!(oi->ip_dyn_features & OCFS2_HAS_XATTR_FL))
 		return 0;
 
+	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL) {
+		ret = ocfs2_lock_refcount_tree(OCFS2_SB(inode->i_sb),
+					       le64_to_cpu(di->i_refcount_loc),
+					       1, &ref_tree, &ref_root_bh);
+		if (ret) {
+			mlog_errno(ret);
+			goto out;
+		}
+		ref_ci = &ref_tree->rf_ci;
+
+	}
+
 	if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL) {
-		ret = ocfs2_xattr_ibody_remove(inode, di_bh);
+		ret = ocfs2_xattr_ibody_remove(inode, di_bh,
+					       ref_ci, ref_root_bh);
 		if (ret < 0) {
 			mlog_errno(ret);
 			goto out;
@@ -1937,7 +2034,8 @@ int ocfs2_xattr_remove(struct inode *inode, struct buffer_head *di_bh)
 
 	if (di->i_xattr_loc) {
 		ret = ocfs2_xattr_free_block(inode,
-					     le64_to_cpu(di->i_xattr_loc));
+					     le64_to_cpu(di->i_xattr_loc),
+					     ref_ci, ref_root_bh);
 		if (ret < 0) {
 			mlog_errno(ret);
 			goto out;
@@ -1971,6 +2069,9 @@ int ocfs2_xattr_remove(struct inode *inode, struct buffer_head *di_bh)
 out_commit:
 	ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
 out:
+	if (ref_tree)
+		ocfs2_unlock_refcount_tree(OCFS2_SB(inode->i_sb), ref_tree, 1);
+	brelse(ref_root_bh);
 	return ret;
 }
 
@@ -4989,7 +5090,7 @@ static int ocfs2_rm_xattr_cluster(struct inode *inode,
 	struct ocfs2_extent_tree et;
 
 	ret = ocfs2_iterate_xattr_buckets(inode, blkno, len,
-					  ocfs2_delete_xattr_in_bucket, NULL);
+					  ocfs2_delete_xattr_in_bucket, para);
 	if (ret) {
 		mlog_errno(ret);
 		return ret;
@@ -5378,7 +5479,7 @@ static int ocfs2_delete_xattr_in_bucket(struct inode *inode,
 					struct ocfs2_xattr_bucket *bucket,
 					void *para)
 {
-	int ret = 0;
+	int ret = 0, ref_credits;
 	struct ocfs2_xattr_header *xh = bucket_xh(bucket);
 	u16 i;
 	struct ocfs2_xattr_entry *xe;
@@ -5386,7 +5487,9 @@ static int ocfs2_delete_xattr_in_bucket(struct inode *inode,
 	struct ocfs2_xattr_set_ctxt ctxt = {NULL, NULL,};
 	int credits = ocfs2_remove_extent_credits(osb->sb) +
 		ocfs2_blocks_per_xattr_bucket(inode->i_sb);
-
+	struct ocfs2_xattr_value_root *xv;
+	struct ocfs2_rm_xattr_bucket_para *args =
+			(struct ocfs2_rm_xattr_bucket_para *)para;
 
 	ocfs2_init_dealloc_ctxt(&ctxt.dealloc);
 
@@ -5395,7 +5498,16 @@ static int ocfs2_delete_xattr_in_bucket(struct inode *inode,
 		if (ocfs2_xattr_is_local(xe))
 			continue;
 
-		ctxt.handle = ocfs2_start_trans(osb, credits);
+		ret = ocfs2_get_xattr_tree_value_root(inode->i_sb, bucket,
+						      i, &xv, NULL);
+
+		ret = ocfs2_lock_xattr_remove_allocators(inode, xv,
+							 args->ref_ci,
+							 args->ref_root_bh,
+							 &ctxt.meta_ac,
+							 &ref_credits);
+
+		ctxt.handle = ocfs2_start_trans(osb, credits + ref_credits);
 		if (IS_ERR(ctxt.handle)) {
 			ret = PTR_ERR(ctxt.handle);
 			mlog_errno(ret);
@@ -5406,12 +5518,18 @@ static int ocfs2_delete_xattr_in_bucket(struct inode *inode,
 							i, 0, &ctxt);
 
 		ocfs2_commit_trans(osb, ctxt.handle);
+		if (ctxt.meta_ac) {
+			ocfs2_free_alloc_context(ctxt.meta_ac);
+			ctxt.meta_ac = NULL;
+		}
 		if (ret) {
 			mlog_errno(ret);
 			break;
 		}
 	}
 
+	if (ctxt.meta_ac)
+		ocfs2_free_alloc_context(ctxt.meta_ac);
 	ocfs2_schedule_truncate_log_flush(osb, 1);
 	ocfs2_run_deallocs(osb, &ctxt.dealloc);
 	return ret;