btrfs-progs/common/clear-cache.c

620 lines
15 KiB
C

/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include "kerncompat.h"
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include "kernel-lib/rbtree.h"
#include "kernel-shared/accessors.h"
#include "kernel-shared/extent-io-tree.h"
#include "kernel-shared/uapi/btrfs_tree.h"
#include "kernel-shared/disk-io.h"
#include "kernel-shared/ctree.h"
#include "kernel-shared/free-space-cache.h"
#include "kernel-shared/free-space-tree.h"
#include "kernel-shared/volumes.h"
#include "kernel-shared/transaction.h"
#include "kernel-shared/file-item.h"
#include "common/internal.h"
#include "common/messages.h"
#include "check/repair.h"
#include "check/mode-common.h"
#include "common/clear-cache.h"
/*
* Number of free space cache inodes to delete in one transaction.
*
* This is to speedup the v1 space cache deletion for large fs.
*/
#define NR_BLOCK_GROUP_CLUSTER (16)
int btrfs_clear_v1_cache(struct btrfs_fs_info *fs_info)
{
struct btrfs_trans_handle *trans;
struct btrfs_block_group *bg_cache;
int nr_handled = 0;
u64 current = 0;
int ret = 0;
trans = btrfs_start_transaction(fs_info->tree_root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
errno = -ret;
error_msg(ERROR_MSG_START_TRANS, "%m");
return ret;
}
/* Clear all free space cache inodes and its extent data */
while (1) {
bg_cache = btrfs_lookup_first_block_group(fs_info, current);
if (!bg_cache)
break;
ret = btrfs_clear_free_space_cache(trans, bg_cache);
if (ret < 0) {
btrfs_abort_transaction(trans, ret);
return ret;
}
nr_handled++;
if (nr_handled == NR_BLOCK_GROUP_CLUSTER) {
ret = btrfs_commit_transaction(trans, fs_info->tree_root);
if (ret < 0) {
errno = -ret;
error_msg(ERROR_MSG_START_TRANS, "%m");
return ret;
}
trans = btrfs_start_transaction(fs_info->tree_root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
errno = -ret;
error_msg(ERROR_MSG_START_TRANS, "%m");
return ret;
}
}
current = bg_cache->start + bg_cache->length;
}
btrfs_set_super_cache_generation(fs_info->super_copy, (u64)-1);
ret = btrfs_commit_transaction(trans, fs_info->tree_root);
if (ret < 0) {
errno = -ret;
error_msg(ERROR_MSG_START_TRANS, "%m");
}
return ret;
}
int do_clear_free_space_cache(struct btrfs_fs_info *fs_info, int clear_version)
{
int ret = 0;
if (clear_version == 1) {
if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE))
warning(
"free space cache v2 detected, use --clear-space-cache v2, proceeding with clearing v1");
ret = btrfs_clear_v1_cache(fs_info);
if (ret) {
error("failed to clear free space cache");
ret = 1;
} else {
printf("Free space cache cleared\n");
}
} else if (clear_version == 2) {
if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
printf("no free space cache v2 to clear\n");
ret = 0;
goto close_out;
}
printf("Clear free space cache v2\n");
ret = btrfs_clear_free_space_tree(fs_info);
if (ret) {
error("failed to clear free space cache v2: %d", ret);
ret = 1;
} else {
printf("free space cache v2 cleared\n");
}
}
close_out:
return ret;
}
static int check_free_space_tree(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_key key = { 0 };
struct btrfs_path path = { 0 };
int ret = 0;
while (1) {
struct btrfs_block_group *bg;
u64 cur_start = key.objectid;
ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
if (ret < 0)
goto out;
/*
* We should be landing on an item, so if we're above the
* nritems we know we hit the end of the tree.
*/
if (path.slots[0] >= btrfs_header_nritems(path.nodes[0]))
break;
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
if (key.type != BTRFS_FREE_SPACE_INFO_KEY) {
fprintf(stderr,
"Failed to find a space info key at %llu [%llu %u %llu]\n",
cur_start, key.objectid, key.type, key.offset);
ret = -EINVAL;
goto out;
}
bg = btrfs_lookup_first_block_group(fs_info, key.objectid);
if (!bg) {
fprintf(stderr,
"We have a space info key for a block group that doesn't exist\n");
ret = -EINVAL;
goto out;
}
btrfs_release_path(&path);
key.objectid += key.offset;
key.offset = 0;
}
ret = 0;
out:
btrfs_release_path(&path);
return ret;
}
static int check_free_space_trees(struct btrfs_root *root)
{
struct btrfs_root *free_space_root;
struct rb_node *n;
struct btrfs_key key = {
.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID,
.type = BTRFS_ROOT_ITEM_KEY,
.offset = 0,
};
int ret = 0;
free_space_root = btrfs_global_root(root->fs_info, &key);
while (1) {
ret = check_free_space_tree(free_space_root);
if (ret)
break;
n = rb_next(&root->rb_node);
if (!n)
break;
free_space_root = rb_entry(n, struct btrfs_root, rb_node);
if (root->root_key.objectid != BTRFS_FREE_SPACE_TREE_OBJECTID)
break;
}
return ret;
}
static int check_cache_range(struct btrfs_root *root,
struct btrfs_block_group *cache,
u64 offset, u64 bytes)
{
struct btrfs_free_space *entry;
u64 *logical;
u64 bytenr;
int stripe_len;
int i, nr, ret;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
ret = btrfs_rmap_block(root->fs_info,
cache->start, bytenr,
&logical, &nr, &stripe_len);
if (ret)
return ret;
while (nr--) {
if (logical[nr] + stripe_len <= offset)
continue;
if (offset + bytes <= logical[nr])
continue;
if (logical[nr] == offset) {
if (stripe_len >= bytes) {
free(logical);
return 0;
}
bytes -= stripe_len;
offset += stripe_len;
} else if (logical[nr] < offset) {
if (logical[nr] + stripe_len >=
offset + bytes) {
free(logical);
return 0;
}
bytes = (offset + bytes) -
(logical[nr] + stripe_len);
offset = logical[nr] + stripe_len;
} else {
/*
* Could be tricky, the super may land in the
* middle of the area we're checking. First
* check the easiest case, it's at the end.
*/
if (logical[nr] + stripe_len >=
bytes + offset) {
bytes = logical[nr] - offset;
continue;
}
/* Check the left side */
ret = check_cache_range(root, cache,
offset,
logical[nr] - offset);
if (ret) {
free(logical);
return ret;
}
/* Now we continue with the right side */
bytes = (offset + bytes) -
(logical[nr] + stripe_len);
offset = logical[nr] + stripe_len;
}
}
free(logical);
}
entry = btrfs_find_free_space(cache->free_space_ctl, offset, bytes);
if (!entry) {
fprintf(stderr, "there is no free space entry for %llu-%llu\n",
offset, offset+bytes);
return -EINVAL;
}
if (entry->offset != offset) {
fprintf(stderr, "wanted offset %llu, found %llu\n", offset,
entry->offset);
return -EINVAL;
}
if (entry->bytes != bytes) {
fprintf(stderr, "wanted bytes %llu, found %llu for off %llu\n",
bytes, entry->bytes, offset);
return -EINVAL;
}
unlink_free_space(cache->free_space_ctl, entry);
free(entry);
return 0;
}
static int verify_space_cache(struct btrfs_root *root,
struct btrfs_block_group *cache,
struct extent_io_tree *used)
{
u64 start, end, last_end, bg_end;
int ret = 0;
start = cache->start;
bg_end = cache->start + cache->length;
last_end = start;
while (start < bg_end) {
ret = find_first_extent_bit(used, cache->start, &start, &end,
EXTENT_DIRTY, NULL);
if (ret || start >= bg_end) {
ret = 0;
break;
}
if (last_end < start) {
ret = check_cache_range(root, cache, last_end,
start - last_end);
if (ret)
return ret;
}
end = min(end, bg_end - 1);
clear_extent_dirty(used, start, end, NULL);
start = end + 1;
last_end = start;
}
if (last_end < bg_end)
ret = check_cache_range(root, cache, last_end,
bg_end - last_end);
if (!ret &&
!RB_EMPTY_ROOT(&cache->free_space_ctl->free_space_offset)) {
fprintf(stderr, "There are still entries left in the space "
"cache\n");
ret = -EINVAL;
}
return ret;
}
static int check_space_cache(struct btrfs_root *root, struct task_ctx *task_ctx)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct extent_io_tree used;
struct btrfs_block_group *cache;
u64 start = BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE;
int ret;
int error = 0;
extent_io_tree_init(fs_info, &used, 0);
ret = btrfs_mark_used_blocks(fs_info, &used);
if (ret)
return ret;
while (1) {
task_ctx->item_count++;
cache = btrfs_lookup_first_block_group(fs_info, start);
if (!cache)
break;
start = cache->start + cache->length;
if (!cache->free_space_ctl) {
if (btrfs_init_free_space_ctl(cache,
fs_info->sectorsize)) {
ret = -ENOMEM;
break;
}
} else {
btrfs_remove_free_space_cache(cache);
}
if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) {
ret = exclude_super_stripes(fs_info, cache);
if (ret) {
errno = -ret;
fprintf(stderr,
"could not exclude super stripes: %m\n");
error++;
continue;
}
ret = load_free_space_tree(fs_info, cache);
free_excluded_extents(fs_info, cache);
if (ret < 0) {
errno = -ret;
fprintf(stderr,
"could not load free space tree: %m\n");
error++;
continue;
}
error += ret;
} else {
ret = load_free_space_cache(fs_info, cache);
if (ret < 0)
error++;
if (ret <= 0)
continue;
}
ret = verify_space_cache(root, cache, &used);
if (ret) {
fprintf(stderr, "cache appears valid but isn't %llu\n",
cache->start);
error++;
}
}
extent_io_tree_release(&used);
return error ? -EINVAL : 0;
}
int validate_free_space_cache(struct btrfs_root *root, struct task_ctx *task_ctx)
{
struct btrfs_fs_info *fs_info = root->fs_info;
int ret;
/*
* If cache generation is between 0 and -1ULL, sb generation must be
* equal to sb cache generation or the v1 space caches are outdated.
*/
if (btrfs_super_cache_generation(fs_info->super_copy) != -1ULL &&
btrfs_super_cache_generation(fs_info->super_copy) != 0 &&
btrfs_super_generation(fs_info->super_copy) !=
btrfs_super_cache_generation(fs_info->super_copy)) {
printf(
"cache and super generation don't match, space cache will be invalidated\n");
return 0;
}
ret = check_space_cache(root, task_ctx);
if (!ret && btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE))
ret = check_free_space_trees(root);
if (ret && btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE) &&
opt_check_repair) {
ret = do_clear_free_space_cache(fs_info, 2);
if (ret)
goto out;
ret = btrfs_create_free_space_tree(fs_info);
if (ret)
error("couldn't repair freespace tree");
}
out:
return ret ? -EINVAL : 0;
}
int truncate_free_ino_items(struct btrfs_root *root)
{
struct btrfs_key key = { .objectid = BTRFS_FREE_INO_OBJECTID,
.type = (u8)-1,
.offset = (u64)-1 };
struct btrfs_trans_handle *trans;
int ret;
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
error_msg(ERROR_MSG_START_TRANS, "inode-cache removal");
return PTR_ERR(trans);
}
while (1) {
struct extent_buffer *leaf;
struct btrfs_file_extent_item *fi;
struct btrfs_root *csum_root;
struct btrfs_key found_key;
struct btrfs_path path = { 0 };
u8 found_type;
ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
if (ret < 0) {
btrfs_abort_transaction(trans, ret);
goto out;
} else if (ret > 0) {
ret = 0;
/* No more items, finished truncating */
if (path.slots[0] == 0) {
btrfs_release_path(&path);
goto out;
}
path.slots[0]--;
}
fi = NULL;
leaf = path.nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path.slots[0]);
found_type = found_key.type;
/* Ino cache also has free space bitmaps in the fs stree */
if (found_key.objectid != BTRFS_FREE_INO_OBJECTID &&
found_key.objectid != BTRFS_FREE_SPACE_OBJECTID) {
btrfs_release_path(&path);
/* Now delete the FREE_SPACE_OBJECTID */
if (key.objectid == BTRFS_FREE_INO_OBJECTID) {
key.objectid = BTRFS_FREE_SPACE_OBJECTID;
continue;
}
break;
}
if (found_type == BTRFS_EXTENT_DATA_KEY) {
int extent_type;
u64 extent_disk_bytenr;
u64 extent_num_bytes;
u64 extent_offset;
fi = btrfs_item_ptr(leaf, path.slots[0],
struct btrfs_file_extent_item);
extent_type = btrfs_file_extent_type(leaf, fi);
UASSERT(extent_type == BTRFS_FILE_EXTENT_REG);
extent_disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
extent_num_bytes = btrfs_file_extent_disk_num_bytes (leaf, fi);
extent_offset = found_key.offset -
btrfs_file_extent_offset(leaf, fi);
UASSERT(extent_offset == 0);
ret = btrfs_free_extent(trans, extent_disk_bytenr,
extent_num_bytes, 0,
root->objectid,
BTRFS_FREE_INO_OBJECTID, 0);
if (ret < 0) {
btrfs_abort_transaction(trans, ret);
btrfs_release_path(&path);
goto out;
}
csum_root = btrfs_csum_root(trans->fs_info,
extent_disk_bytenr);
ret = btrfs_del_csums(trans, csum_root,
extent_disk_bytenr,
extent_num_bytes);
if (ret < 0) {
btrfs_abort_transaction(trans, ret);
btrfs_release_path(&path);
goto out;
}
}
ret = btrfs_del_item(trans, root, &path);
BUG_ON(ret);
btrfs_release_path(&path);
}
btrfs_commit_transaction(trans, root);
out:
return ret;
}
int clear_ino_cache_items(struct btrfs_fs_info *fs_info)
{
int ret;
struct btrfs_path path = { 0 };
struct btrfs_key key;
key.objectid = BTRFS_FS_TREE_OBJECTID;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = 0;
ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, &path, 0, 0);
if (ret < 0)
return ret;
while(1) {
struct btrfs_key found_key;
btrfs_item_key_to_cpu(path.nodes[0], &found_key, path.slots[0]);
if (found_key.type == BTRFS_ROOT_ITEM_KEY &&
is_fstree(found_key.objectid)) {
struct btrfs_root *root;
found_key.offset = (u64)-1;
root = btrfs_read_fs_root(fs_info, &found_key);
if (IS_ERR(root))
goto next;
ret = truncate_free_ino_items(root);
if (ret)
goto out;
printf("Successfully cleaned up ino cache for root id: %lld\n",
root->objectid);
} else {
/* If we get a negative tree this means it's the last one */
if ((s64)found_key.objectid < 0 &&
found_key.type == BTRFS_ROOT_ITEM_KEY)
goto out;
}
/*
* Only fs roots contain an ino cache information - either
* FS_TREE_OBJECTID or subvol id >= BTRFS_FIRST_FREE_OBJECTID
*/
next:
if (key.objectid == BTRFS_FS_TREE_OBJECTID) {
key.objectid = BTRFS_FIRST_FREE_OBJECTID;
btrfs_release_path(&path);
ret = btrfs_search_slot(NULL, fs_info->tree_root, &key,
&path, 0, 0);
if (ret < 0)
return ret;
} else {
ret = btrfs_next_item(fs_info->tree_root, &path);
if (ret < 0) {
goto out;
} else if (ret > 0) {
ret = 0;
goto out;
}
}
}
out:
btrfs_release_path(&path);
return ret;
}