X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=inode-item.c;h=1cc106670cd4bfd1ebadb30b6c254b68fee8dd08;hb=6af3cc08ddb5c0165d357ffa36422c2716ebd2a0;hp=799a91db804c1656d38fd459ca79c030502d71a8;hpb=f12d799856c27ba425db93e5829f6b858bc03561;p=platform%2Fupstream%2Fbtrfs-progs.git

diff --git a/inode-item.c b/inode-item.c
index 799a91d..1cc1066 100644
--- a/inode-item.c
+++ b/inode-item.c
@@ -16,41 +16,437 @@
  * Boston, MA 021110-1307, USA.
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include "kerncompat.h"
-#include "radix-tree.h"
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
+#include "hash.h"
+
+static int find_name_in_backref(struct btrfs_path *path, const char * name,
+			 int name_len, struct btrfs_inode_ref **ref_ret)
+{
+	struct extent_buffer *leaf;
+	struct btrfs_inode_ref *ref;
+	unsigned long ptr;
+	unsigned long name_ptr;
+	u32 item_size;
+	u32 cur_offset = 0;
+	int len;
+
+	leaf = path->nodes[0];
+	item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+	ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+	while (cur_offset < item_size) {
+		ref = (struct btrfs_inode_ref *)(ptr + cur_offset);
+		len = btrfs_inode_ref_name_len(leaf, ref);
+		name_ptr = (unsigned long)(ref + 1);
+		cur_offset += len + sizeof(*ref);
+		if (len != name_len)
+			continue;
+		if (memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0) {
+			*ref_ret = ref;
+			return 1;
+		}
+	}
+	return 0;
+}
+
+int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *root,
+			   const char *name, int name_len,
+			   u64 inode_objectid, u64 ref_objectid, u64 index)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	struct btrfs_inode_ref *ref;
+	unsigned long ptr;
+	int ret;
+	int ins_len = name_len + sizeof(*ref);
+
+	key.objectid = inode_objectid;
+	key.offset = ref_objectid;
+	key.type = BTRFS_INODE_REF_KEY;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	ret = btrfs_insert_empty_item(trans, root, path, &key,
+				      ins_len);
+	if (ret == -EEXIST) {
+		u32 old_size;
+
+		if (find_name_in_backref(path, name, name_len, &ref))
+			goto out;
+
+		old_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
+		ret = btrfs_extend_item(root, path, ins_len);
+		BUG_ON(ret);
+		ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
+				     struct btrfs_inode_ref);
+		ref = (struct btrfs_inode_ref *)((unsigned long)ref + old_size);
+		btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
+		btrfs_set_inode_ref_index(path->nodes[0], ref, index);
+		ptr = (unsigned long)(ref + 1);
+		ret = 0;
+	} else if (ret < 0) {
+		if (ret == -EOVERFLOW)
+			ret = -EMLINK;
+		goto out;
+	} else {
+		ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
+				     struct btrfs_inode_ref);
+		btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
+		btrfs_set_inode_ref_index(path->nodes[0], ref, index);
+		ptr = (unsigned long)(ref + 1);
+	}
+	write_extent_buffer(path->nodes[0], name, ptr, name_len);
+	btrfs_mark_buffer_dirty(path->nodes[0]);
+
+out:
+	btrfs_free_path(path);
+
+	if (ret == -EMLINK) {
+		if (btrfs_fs_incompat(root->fs_info, EXTENDED_IREF))
+			ret = btrfs_insert_inode_extref(trans, root, name,
+							name_len,
+							inode_objectid,
+							ref_objectid, index);
+	}
+	return ret;
+}
+
+int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
+		       *root, struct btrfs_path *path,
+		       struct btrfs_key *location, int mod)
+{
+	int ins_len = mod < 0 ? -1 : 0;
+	int cow = mod != 0;
+	int ret;
+	int slot;
+	struct extent_buffer *leaf;
+	struct btrfs_key found_key;
+
+	ret = btrfs_search_slot(trans, root, location, path, ins_len, cow);
+	if (ret > 0 && location->type == BTRFS_ROOT_ITEM_KEY &&
+	    location->offset == (u64)-1 && path->slots[0] != 0) {
+		slot = path->slots[0] - 1;
+		leaf = path->nodes[0];
+		btrfs_item_key_to_cpu(leaf, &found_key, slot);
+		if (found_key.objectid == location->objectid &&
+		    found_key.type == location->type) {
+			path->slots[0]--;
+			return 0;
+		}
+	}
+	return ret;
+}
 
 int btrfs_insert_inode(struct btrfs_trans_handle *trans, struct btrfs_root
 		       *root, u64 objectid, struct btrfs_inode_item
 		       *inode_item)
 {
-	struct btrfs_path path;
-	struct btrfs_key key;
 	int ret;
+	struct btrfs_key key;
+
 	key.objectid = objectid;
-	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+	key.type = BTRFS_INODE_ITEM_KEY;
 	key.offset = 0;
 
-	btrfs_init_path(&path);
 	ret = btrfs_insert_item(trans, root, &key, inode_item,
 				sizeof(*inode_item));
-	btrfs_release_path(root, &path);
 	return ret;
 }
 
-int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
-		       *root, struct btrfs_path *path, u64 objectid, int mod)
+struct btrfs_inode_ref *btrfs_lookup_inode_ref(struct btrfs_trans_handle *trans,
+		struct btrfs_root *root, struct btrfs_path *path,
+		const char *name, int namelen, u64 ino, u64 parent_ino,
+		int ins_len)
 {
 	struct btrfs_key key;
-	int ins_len = mod < 0 ? -1 : 0;
-	int cow = mod != 0;
+	struct btrfs_inode_ref *ret_inode_ref = NULL;
+	int ret = 0;
 
-	key.objectid = objectid;
-	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
-	key.offset = 0;
-	return btrfs_search_slot(trans, root, &key, path, ins_len, cow);
+	key.objectid = ino;
+	key.type = BTRFS_INODE_REF_KEY;
+	key.offset = parent_ino;
+
+	ret = btrfs_search_slot(trans, root, &key, path, ins_len,
+				ins_len ? 1 : 0);
+	if (ret)
+		goto out;
+
+	find_name_in_backref(path, name, namelen, &ret_inode_ref);
+out:
+	if (ret < 0)
+		return ERR_PTR(ret);
+	else
+		return ret_inode_ref;
+}
+
+static int btrfs_find_name_in_ext_backref(struct btrfs_path *path,
+		u64 parent_ino, const char *name, int namelen,
+		struct btrfs_inode_extref **extref_ret)
+{
+	struct extent_buffer *node;
+	struct btrfs_inode_extref *extref;
+	unsigned long ptr;
+	unsigned long name_ptr;
+	u32 item_size;
+	u32 cur_offset = 0;
+	int ref_name_len;
+	int slot;
+
+	node = path->nodes[0];
+	slot = path->slots[0];
+	item_size = btrfs_item_size_nr(node, slot);
+	ptr = btrfs_item_ptr_offset(node, slot);
+
+	/*
+	 * Search all extended backrefs in this item. We're only looking
+	 * through any collisions so most of the time this is just going to
+	 * compare against one buffer. If all is well, we'll return success and
+	 * the inode ref object.
+	 */
+	while (cur_offset < item_size) {
+		extref = (struct btrfs_inode_extref *) (ptr + cur_offset);
+		name_ptr = (unsigned long)(&extref->name);
+		ref_name_len = btrfs_inode_extref_name_len(node, extref);
+
+		if (ref_name_len == namelen &&
+		    btrfs_inode_extref_parent(node, extref) == parent_ino &&
+		    (memcmp_extent_buffer(node, name, name_ptr, namelen) == 0))
+		{
+			if (extref_ret)
+				*extref_ret = extref;
+			return 1;
+		}
+
+		cur_offset += ref_name_len + sizeof(*extref);
+	}
+
+	return 0;
+}
+
+struct btrfs_inode_extref *btrfs_lookup_inode_extref(struct btrfs_trans_handle
+		*trans, struct btrfs_path *path, struct btrfs_root *root,
+		u64 ino, u64 parent_ino, u64 index, const char *name,
+		int namelen, int ins_len)
+{
+	struct btrfs_key key;
+	struct btrfs_inode_extref *extref;
+	int ret = 0;
+
+	key.objectid = ino;
+	key.type = BTRFS_INODE_EXTREF_KEY;
+	key.offset = btrfs_extref_hash(parent_ino, name, namelen);
+
+	ret = btrfs_search_slot(trans, root, &key, path, ins_len,
+			ins_len ? 1 : 0);
+	if (ret < 0)
+		return ERR_PTR(ret);
+	if (ret > 0)
+		return NULL;
+	if (!btrfs_find_name_in_ext_backref(path, parent_ino, name,
+					    namelen, &extref))
+		return NULL;
+
+	return extref;
+}
+
+int btrfs_del_inode_extref(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *root,
+			   const char *name, int name_len,
+			   u64 inode_objectid, u64 ref_objectid,
+			   u64 *index)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	struct btrfs_inode_extref *extref;
+	struct extent_buffer *leaf;
+	int ret;
+	int del_len = name_len + sizeof(*extref);
+	unsigned long ptr;
+	unsigned long item_start;
+	u32 item_size;
+
+	key.objectid = inode_objectid;
+	key.type = BTRFS_INODE_EXTREF_KEY;
+	key.offset = btrfs_extref_hash(ref_objectid, name, name_len);
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+	if (ret > 0)
+		ret = -ENOENT;
+	if (ret < 0)
+		goto out;
+
+	/*
+	 * Sanity check - did we find the right item for this name?  This
+	 * should always succeed so error here will make the FS readonly.
+	 */
+	if (!btrfs_find_name_in_ext_backref(path, ref_objectid,
+					    name, name_len, &extref)) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	leaf = path->nodes[0];
+	item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+	if (index)
+		*index = btrfs_inode_extref_index(leaf, extref);
+
+	if (del_len == item_size) {
+		/*
+		 * Common case only one ref in the item, remove the whole item.
+		 */
+		ret = btrfs_del_item(trans, root, path);
+		goto out;
+	}
+
+	ptr = (unsigned long)extref;
+	item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
+
+	memmove_extent_buffer(leaf, ptr, ptr + del_len,
+			      item_size - (ptr + del_len - item_start));
+
+	btrfs_truncate_item(root, path, item_size - del_len, 1);
+
+out:
+	btrfs_free_path(path);
+
+	return ret;
+}
+
+/*
+ * btrfs_insert_inode_extref() - Inserts an extended inode ref into a tree.
+ *
+ * The caller must have checked against BTRFS_LINK_MAX already.
+ */
+int btrfs_insert_inode_extref(struct btrfs_trans_handle *trans,
+			      struct btrfs_root *root,
+			      const char *name, int name_len,
+			      u64 inode_objectid, u64 ref_objectid, u64 index)
+{
+	struct btrfs_inode_extref *extref;
+	int ret;
+	int ins_len = name_len + sizeof(*extref);
+	unsigned long ptr;
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	struct extent_buffer *leaf;
+	struct btrfs_item *item;
+
+	key.objectid = inode_objectid;
+	key.type = BTRFS_INODE_EXTREF_KEY;
+	key.offset = btrfs_extref_hash(ref_objectid, name, name_len);
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	ret = btrfs_insert_empty_item(trans, root, path, &key,
+				      ins_len);
+	if (ret == -EEXIST) {
+		if (btrfs_find_name_in_ext_backref(path, ref_objectid,
+						   name, name_len, NULL))
+			goto out;
+
+		btrfs_extend_item(root, path, ins_len);
+		ret = 0;
+	}
+
+	if (ret < 0)
+		goto out;
+
+	leaf = path->nodes[0];
+	item = btrfs_item_nr(path->slots[0]);
+	ptr = (unsigned long)btrfs_item_ptr(leaf, path->slots[0], char);
+	ptr += btrfs_item_size(leaf, item) - ins_len;
+	extref = (struct btrfs_inode_extref *)ptr;
+
+	btrfs_set_inode_extref_name_len(path->nodes[0], extref, name_len);
+	btrfs_set_inode_extref_index(path->nodes[0], extref, index);
+	btrfs_set_inode_extref_parent(path->nodes[0], extref, ref_objectid);
+
+	ptr = (unsigned long)&extref->name;
+	write_extent_buffer(path->nodes[0], name, ptr, name_len);
+	btrfs_mark_buffer_dirty(path->nodes[0]);
+
+out:
+	btrfs_free_path(path);
+
+	return ret;
+}
+
+int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
+			struct btrfs_root *root, const char *name, int name_len,
+			u64 ino, u64 parent_ino, u64 *index)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	struct btrfs_inode_ref *ref;
+	struct extent_buffer *leaf;
+	unsigned long ptr;
+	unsigned long item_start;
+	u32 item_size;
+	u32 sub_item_len;
+	int ret;
+	int search_ext_refs = 0;
+	int del_len = name_len + sizeof(*ref);
+
+	key.objectid = ino;
+	key.offset = parent_ino;
+	key.type = BTRFS_INODE_REF_KEY;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+	if (ret > 0) {
+		ret = -ENOENT;
+		search_ext_refs = 1;
+		goto out;
+	} else if (ret < 0) {
+		goto out;
+	}
+	if (!find_name_in_backref(path, name, name_len, &ref)) {
+		ret = -ENOENT;
+		search_ext_refs = 1;
+		goto out;
+	}
+	leaf = path->nodes[0];
+	item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+
+	if (index)
+		*index = btrfs_inode_ref_index(leaf, ref);
+
+	if (del_len == item_size) {
+		ret = btrfs_del_item(trans, root, path);
+		goto out;
+	}
+	ptr = (unsigned long)ref;
+	sub_item_len = name_len + sizeof(*ref);
+	item_start = btrfs_item_ptr_offset(leaf, path->slots[0]);
+	memmove_extent_buffer(leaf, ptr, ptr + sub_item_len,
+			      item_size - (ptr + sub_item_len - item_start));
+	btrfs_truncate_item(root, path, item_size - sub_item_len, 1);
+	btrfs_mark_buffer_dirty(path->nodes[0]);
+out:
+	btrfs_free_path(path);
+
+	if (search_ext_refs &&
+	    btrfs_fs_incompat(root->fs_info, EXTENDED_IREF)) {
+		/*
+		 * No refs were found, or we could not find the name in our ref
+		 * array. Find and remove the extended inode ref then.
+		 */
+		return btrfs_del_inode_extref(trans, root, name, name_len,
+					      ino, parent_ino, index);
+	}
+
+	return ret;
 }