Commit 13a8a7c8 authored by Yan, Zheng's avatar Yan, Zheng Committed by Chris Mason
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Btrfs: do not reuse objectid of deleted snapshot/subvol



The new back reference format does not allow reusing objectid of
deleted snapshot/subvol. So we use ++highest_objectid to allocate
objectid for new snapshot/subvol.

Now we use ++highest_objectid to allocate objectid for both new inode
and new snapshot/subvolume, so this patch removes 'find hole' code in
btrfs_find_free_objectid.
Signed-off-by: default avatarYan Zheng <zheng.yan@oracle.com>
Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 1c4850e2
......@@ -1007,8 +1007,8 @@ struct btrfs_root {
u32 stripesize;
u32 type;
u64 highest_inode;
u64 last_inode_alloc;
u64 highest_objectid;
int ref_cows;
int track_dirty;
u64 defrag_trans_start;
......
......@@ -895,8 +895,7 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
root->fs_info = fs_info;
root->objectid = objectid;
root->last_trans = 0;
root->highest_inode = 0;
root->last_inode_alloc = 0;
root->highest_objectid = 0;
root->name = NULL;
root->in_sysfs = 0;
root->inode_tree.rb_node = NULL;
......@@ -1095,7 +1094,6 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
struct btrfs_fs_info *fs_info = tree_root->fs_info;
struct btrfs_path *path;
struct extent_buffer *l;
u64 highest_inode;
u64 generation;
u32 blocksize;
int ret = 0;
......@@ -1110,7 +1108,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
kfree(root);
return ERR_PTR(ret);
}
goto insert;
goto out;
}
__setup_root(tree_root->nodesize, tree_root->leafsize,
......@@ -1120,39 +1118,30 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
path = btrfs_alloc_path();
BUG_ON(!path);
ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
if (ret != 0) {
if (ret > 0)
ret = -ENOENT;
goto out;
if (ret == 0) {
l = path->nodes[0];
read_extent_buffer(l, &root->root_item,
btrfs_item_ptr_offset(l, path->slots[0]),
sizeof(root->root_item));
memcpy(&root->root_key, location, sizeof(*location));
}
l = path->nodes[0];
read_extent_buffer(l, &root->root_item,
btrfs_item_ptr_offset(l, path->slots[0]),
sizeof(root->root_item));
memcpy(&root->root_key, location, sizeof(*location));
ret = 0;
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
if (ret) {
kfree(root);
if (ret > 0)
ret = -ENOENT;
return ERR_PTR(ret);
}
generation = btrfs_root_generation(&root->root_item);
blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
blocksize, generation);
root->commit_root = btrfs_root_node(root);
BUG_ON(!root->node);
insert:
if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
out:
if (location->objectid != BTRFS_TREE_LOG_OBJECTID)
root->ref_cows = 1;
ret = btrfs_find_highest_inode(root, &highest_inode);
if (ret == 0) {
root->highest_inode = highest_inode;
root->last_inode_alloc = highest_inode;
}
}
return root;
}
......
......@@ -177,8 +177,6 @@ int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
ret = btrfs_insert_empty_item(trans, root, path, &key,
sizeof(struct btrfs_inode_item));
if (ret == 0 && objectid > root->highest_inode)
root->highest_inode = objectid;
return ret;
}
......
......@@ -43,9 +43,10 @@ int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
slot = path->slots[0] - 1;
l = path->nodes[0];
btrfs_item_key_to_cpu(l, &found_key, slot);
*objectid = found_key.objectid;
*objectid = max_t(u64, found_key.objectid,
BTRFS_FIRST_FREE_OBJECTID - 1);
} else {
*objectid = BTRFS_FIRST_FREE_OBJECTID;
*objectid = BTRFS_FIRST_FREE_OBJECTID - 1;
}
ret = 0;
error:
......@@ -53,91 +54,27 @@ error:
return ret;
}
/*
* walks the btree of allocated inodes and find a hole.
*/
int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 dirid, u64 *objectid)
{
struct btrfs_path *path;
struct btrfs_key key;
int ret;
int slot = 0;
u64 last_ino = 0;
int start_found;
struct extent_buffer *l;
struct btrfs_key search_key;
u64 search_start = dirid;
mutex_lock(&root->objectid_mutex);
if (root->last_inode_alloc >= BTRFS_FIRST_FREE_OBJECTID &&
root->last_inode_alloc < BTRFS_LAST_FREE_OBJECTID) {
*objectid = ++root->last_inode_alloc;
mutex_unlock(&root->objectid_mutex);
return 0;
}
path = btrfs_alloc_path();
BUG_ON(!path);
search_start = max(search_start, (u64)BTRFS_FIRST_FREE_OBJECTID);
search_key.objectid = search_start;
search_key.type = 0;
search_key.offset = 0;
start_found = 0;
ret = btrfs_search_slot(trans, root, &search_key, path, 0, 0);
if (ret < 0)
goto error;
while (1) {
l = path->nodes[0];
slot = path->slots[0];
if (slot >= btrfs_header_nritems(l)) {
ret = btrfs_next_leaf(root, path);
if (ret == 0)
continue;
if (ret < 0)
goto error;
if (!start_found) {
*objectid = search_start;
start_found = 1;
goto found;
}
*objectid = last_ino > search_start ?
last_ino : search_start;
goto found;
}
btrfs_item_key_to_cpu(l, &key, slot);
if (key.objectid >= search_start) {
if (start_found) {
if (last_ino < search_start)
last_ino = search_start;
if (key.objectid > last_ino) {
*objectid = last_ino;
goto found;
}
} else if (key.objectid > search_start) {
*objectid = search_start;
goto found;
}
}
if (key.objectid >= BTRFS_LAST_FREE_OBJECTID)
break;
if (unlikely(root->highest_objectid < BTRFS_FIRST_FREE_OBJECTID)) {
ret = btrfs_find_highest_inode(root, &root->highest_objectid);
if (ret)
goto out;
}
start_found = 1;
last_ino = key.objectid + 1;
path->slots[0]++;
if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
ret = -ENOSPC;
goto out;
}
BUG_ON(1);
found:
btrfs_release_path(root, path);
btrfs_free_path(path);
BUG_ON(*objectid < search_start);
mutex_unlock(&root->objectid_mutex);
return 0;
error:
btrfs_release_path(root, path);
btrfs_free_path(path);
*objectid = ++root->highest_objectid;
ret = 0;
out:
mutex_unlock(&root->objectid_mutex);
return ret;
}
......@@ -3624,9 +3624,6 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
if (ret != 0)
goto fail;
if (objectid > root->highest_inode)
root->highest_inode = objectid;
inode->i_uid = current_fsuid();
if (dir && (dir->i_mode & S_ISGID)) {
......
......@@ -2951,7 +2951,6 @@ int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
struct btrfs_key tmp_key;
struct btrfs_root *log;
struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
u64 highest_inode;
struct walk_control wc = {
.process_func = process_one_buffer,
.stage = 0,
......@@ -3010,11 +3009,6 @@ again:
path);
BUG_ON(ret);
}
ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode);
if (ret == 0) {
wc.replay_dest->highest_inode = highest_inode;
wc.replay_dest->last_inode_alloc = highest_inode;
}
key.offset = found_key.offset - 1;
wc.replay_dest->log_root = NULL;
......
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