Btrfs: Add inode map, and the start of file extent items

Signed-off-by: Chris Mason <chris.mason@oracle.com>

fs/btrfs/Makefile

@@ -3,7 +3,8 @@ CFLAGS = -g -Wall -Werror
 headers = radix-tree.h ctree.h disk-io.h kerncompat.h print-tree.h list.h \
 	  transaction.h
 objects = ctree.o disk-io.o radix-tree.o mkfs.o extent-tree.o print-tree.o \
-	  root-tree.o dir-item.o hash.o file-item.o inode-item.o
+	  root-tree.o dir-item.o hash.o file-item.o inode-item.o \
+	  inode-map.o \
 
 # if you don't have sparse installed, use ls instead
 CHECKFLAGS=-D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ -Wbitwise \

fs/btrfs/ctree.h

@@ -10,7 +10,8 @@ struct btrfs_trans_handle;
 
 #define BTRFS_ROOT_TREE_OBJECTID 1
 #define BTRFS_EXTENT_TREE_OBJECTID 2
-#define BTRFS_FS_TREE_OBJECTID 3
+#define BTRFS_INODE_MAP_OBJECTID 3
+#define BTRFS_FS_TREE_OBJECTID 4
 
 /*
  * the key defines the order in the tree, and so it also defines (optimal)
@@ -178,31 +179,65 @@ struct btrfs_root_item {
 	__le64 block_limit;
 	__le64 blocks_used;
 	__le32 refs;
-};
+} __attribute__ ((__packed__));
 
-/*
- * in ram representation of the tree.  extent_root is used for all allocations
- * and for the extent tree extent_root root.  current_insert is used
- * only for the extent tree.
- */
-struct btrfs_root {
-	struct btrfs_buffer *node;
-	struct btrfs_buffer *commit_root;
+struct btrfs_file_extent_item {
+	/*
+	 * disk space consumed by the extent, checksum blocks are included
+	 * in these numbers
+	 */
+	__le64 disk_blocknr;
+	__le64 disk_num_blocks;
+	/*
+	 * the logical offset in file bytes (no csums)
+	 * this extent record is for.  This allows a file extent to point
+	 * into the middle of an existing extent on disk, sharing it
+	 * between two snapshots (useful if some bytes in the middle of the
+	 * extent have changed
+	 */
+	__le64 offset;
+	/*
+	 * the logical number of file blocks (no csums included)
+	 */
+	__le64 num_blocks;
+} __attribute__ ((__packed__));
+
+struct btrfs_inode_map_item {
+	struct btrfs_disk_key key;
+} __attribute__ ((__packed__));
+
+struct btrfs_fs_info {
+	struct btrfs_root *fs_root;
 	struct btrfs_root *extent_root;
 	struct btrfs_root *tree_root;
+	struct btrfs_root *inode_root;
 	struct btrfs_key current_insert;
 	struct btrfs_key last_insert;
-	int fp;
 	struct radix_tree_root cache_radix;
 	struct radix_tree_root pinned_radix;
 	struct list_head trans;
 	struct list_head cache;
+	u64 last_inode_alloc;
+	u64 last_inode_alloc_dirid;
 	int cache_size;
-	int ref_cows;
+	int fp;
+	struct btrfs_trans_handle *running_transaction;
+};
+
+/*
+ * in ram representation of the tree.  extent_root is used for all allocations
+ * and for the extent tree extent_root root.  current_insert is used
+ * only for the extent tree.
+ */
+struct btrfs_root {
+	struct btrfs_buffer *node;
+	struct btrfs_buffer *commit_root;
 	struct btrfs_root_item root_item;
 	struct btrfs_key root_key;
+	struct btrfs_fs_info *fs_info;
 	u32 blocksize;
-	struct btrfs_trans_handle *running_transaction;
+	int ref_cows;
+	u32 type;
 };
 
 /* the lower bits in the key flags defines the item type */
@@ -240,11 +275,17 @@ struct btrfs_root {
  * are used, and how many references there are to each block
  */
 #define BTRFS_EXTENT_ITEM_KEY	6
+
+/*
+ * the inode map records which inode numbers are in use and where
+ * they actually live on disk
+ */
+#define BTRFS_INODE_MAP_ITEM_KEY 7
 /*
  * string items are for debugging.  They just store a short string of
  * data in the FS
  */
-#define BTRFS_STRING_ITEM_KEY	7
+#define BTRFS_STRING_ITEM_KEY	8
 
 static inline u64 btrfs_inode_generation(struct btrfs_inode_item *i)
 {
@@ -654,6 +695,57 @@ static inline u8 *btrfs_leaf_data(struct btrfs_leaf *l)
 {
 	return (u8 *)l->items;
 }
+
+static inline u64 btrfs_file_extent_disk_blocknr(struct btrfs_file_extent_item
+						 *e)
+{
+	return le64_to_cpu(e->disk_blocknr);
+}
+
+static inline void btrfs_set_file_extent_disk_blocknr(struct
+						      btrfs_file_extent_item
+						      *e, u64 val)
+{
+	e->disk_blocknr = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_file_extent_disk_num_blocks(struct
+						    btrfs_file_extent_item *e)
+{
+	return le64_to_cpu(e->disk_num_blocks);
+}
+
+static inline void btrfs_set_file_extent_disk_num_blocks(struct
+							 btrfs_file_extent_item
+							 *e, u64 val)
+{
+	e->disk_num_blocks = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_file_extent_offset(struct btrfs_file_extent_item *e)
+{
+	return le64_to_cpu(e->offset);
+}
+
+static inline void btrfs_set_file_extent_offset(struct btrfs_file_extent_item
+						*e, u64 val)
+{
+	e->offset = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_file_extent_num_blocks(struct btrfs_file_extent_item
+					       *e)
+{
+	return le64_to_cpu(e->num_blocks);
+}
+
+static inline void btrfs_set_file_extent_num_blocks(struct
+						    btrfs_file_extent_item *e,
+						    u64 val)
+{
+	e->num_blocks = cpu_to_le64(val);
+}
+
 /* helper function to cast into the data area of the leaf. */
 #define btrfs_item_ptr(leaf, slot, type) \
 	((type *)(btrfs_leaf_data(leaf) + \
@@ -701,4 +793,13 @@ int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
 			  int name_len, int mod);
 int btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path,
 			      char *name, int name_len);
+int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
+			     struct btrfs_root *fs_root,
+			     u64 dirid, u64 *objectid);
+int btrfs_insert_inode_map(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *root,
+			   u64 objectid, struct btrfs_key *location);
+int btrfs_lookup_inode_map(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *root, struct btrfs_path *path,
+			   u64 objectid, int mod);
 #endif

fs/btrfs/debug-tree.c

@@ -15,8 +15,13 @@ int main(int ac, char **av) {
 	printf("fs tree\n");
 	btrfs_print_tree(root, root->node);
 	printf("map tree\n");
-	btrfs_print_tree(root->extent_root, root->extent_root->node);
+	btrfs_print_tree(root->fs_info->extent_root,
+			 root->fs_info->extent_root->node);
+	printf("inode tree\n");
+	btrfs_print_tree(root->fs_info->inode_root,
+			 root->fs_info->inode_root->node);
 	printf("root tree\n");
-	btrfs_print_tree(root->tree_root, root->tree_root->node);
+	btrfs_print_tree(root->fs_info->tree_root,
+			 root->fs_info->tree_root->node);
 	return 0;
 }

fs/btrfs/dir-test.c

@@ -45,13 +45,26 @@ static int ins_one(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 	int ret;
 	char buf[128];
 	unsigned long oid;
+	u64 objectid;
 	struct btrfs_path path;
+	struct btrfs_key inode_map;
 
 	find_num(radix, &oid, 0);
 	sprintf(buf, "str-%lu", oid);
 
+	ret = btrfs_find_free_objectid(trans, root, dir_oid + 1, &objectid);
+	if (ret)
+		goto error;
+
+	inode_map.objectid = objectid;
+	inode_map.flags = 0;
+	inode_map.offset = 0;
+
+	ret = btrfs_insert_inode_map(trans, root, objectid, &inode_map);
+	if (ret)
+		goto error;
 	ret = btrfs_insert_dir_item(trans, root, buf, strlen(buf), dir_oid,
-				    file_oid, 1);
+				    objectid, 1);
 	if (ret)
 		goto error;
 
@@ -120,14 +133,60 @@ static int insert_dup(struct btrfs_trans_handle *trans, struct btrfs_root
 	return 0;
 }
 
+static int del_dir_item(struct btrfs_trans_handle *trans,
+			struct btrfs_root *root,
+			struct radix_tree_root *radix,
+			unsigned long radix_index,
+			struct btrfs_path *path)
+{
+	int ret;
+	unsigned long *ptr;
+	u64 file_objectid;
+	struct btrfs_dir_item *di;
+	struct btrfs_path map_path;
+
+	/* find the inode number of the file */
+	di = btrfs_item_ptr(&path->nodes[0]->leaf, path->slots[0],
+			    struct btrfs_dir_item);
+	file_objectid = btrfs_dir_objectid(di);
+
+	/* delete the directory item */
+	ret = btrfs_del_item(trans, root, path);
+	if (ret)
+		goto out;
+
+	/* delete the inode mapping */
+	btrfs_init_path(&map_path);
+	ret = btrfs_lookup_inode_map(trans, root, &map_path, file_objectid, -1);
+	if (ret)
+		goto out_release;
+	ret = btrfs_del_item(trans, root->fs_info->inode_root, &map_path);
+	if (ret)
+		goto out_release;
+
+	if (root->fs_info->last_inode_alloc > file_objectid)
+		root->fs_info->last_inode_alloc = file_objectid;
+	btrfs_release_path(root, &map_path);
+	ptr = radix_tree_delete(radix, radix_index);
+	if (!ptr) {
+		ret = -5555;
+		goto out;
+	}
+	return 0;
+out_release:
+	btrfs_release_path(root, &map_path);
+out:
+	printf("failed to delete %lu %d\n", radix_index, ret);
+	return -1;
+}
+
 static int del_one(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   struct radix_tree_root *radix)
 {
 	int ret;
 	char buf[128];
 	unsigned long oid;
 	struct btrfs_path path;
-	unsigned long *ptr;
 
 	ret = find_num(radix, &oid, 1);
 	if (ret < 0)
@@ -138,19 +197,14 @@ static int del_one(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 				    strlen(buf), -1);
 	if (ret)
 		goto out_release;
-	ret = btrfs_del_item(trans, root, &path);
+
+	ret = del_dir_item(trans, root, radix, oid, &path);
 	if (ret)
 		goto out_release;
 	btrfs_release_path(root, &path);
-	ptr = radix_tree_delete(radix, oid);
-	if (!ptr) {
-		ret = -5555;
-		goto out;
-	}
-	return 0;
+	return ret;
 out_release:
 	btrfs_release_path(root, &path);
-out:
 	printf("failed to delete %lu %d\n", oid, ret);
 	return -1;
 }
@@ -162,6 +216,8 @@ static int lookup_item(struct btrfs_trans_handle *trans, struct btrfs_root
 	char buf[128];
 	int ret;
 	unsigned long oid;
+	u64 objectid;
+	struct btrfs_dir_item *di;
 
 	ret = find_num(radix, &oid, 1);
 	if (ret < 0)
@@ -170,6 +226,14 @@ static int lookup_item(struct btrfs_trans_handle *trans, struct btrfs_root
 	btrfs_init_path(&path);
 	ret = btrfs_lookup_dir_item(trans, root, &path, dir_oid, buf,
 				    strlen(buf), 0);
+	if (!ret) {
+		di = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0],
+				    struct btrfs_dir_item);
+		objectid = btrfs_dir_objectid(di);
+		btrfs_release_path(root, &path);
+		btrfs_init_path(&path);
+		ret = btrfs_lookup_inode_map(trans, root, &path, objectid, 0);
+	}
 	btrfs_release_path(root, &path);
 	if (ret) {
 		printf("unable to find key %lu\n", oid);
@@ -210,7 +274,6 @@ static int empty_tree(struct btrfs_trans_handle *trans, struct btrfs_root
 	u32 found_len;
 	int ret;
 	int slot;
-	int *ptr;
 	int count = 0;
 	char buf[128];
 	struct btrfs_dir_item *di;
@@ -241,7 +304,7 @@ static int empty_tree(struct btrfs_trans_handle *trans, struct btrfs_root
 		BUG_ON(found_len > 128);
 		buf[found_len] = '\0';
 		found = atoi(buf + 4);
-		ret = btrfs_del_item(trans, root, &path);
+		ret = del_dir_item(trans, root, radix, found, &path);
 		count++;
 		if (ret) {
 			fprintf(stderr,
@@ -250,14 +313,10 @@ static int empty_tree(struct btrfs_trans_handle *trans, struct btrfs_root
 			return -1;
 		}
 		btrfs_release_path(root, &path);
-		ptr = radix_tree_delete(radix, found);
-		if (!ptr)
-			goto error;
 		if (!keep_running)
 			break;
 	}
 	return 0;
-error:
 	fprintf(stderr, "failed to delete from the radix %lu\n", found);
 	return -1;
 }