Select Git revision
disk-io.c 96.16 KiB
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* 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 <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/scatterlist.h>
#include <linux/swap.h>
#include <linux/radix-tree.h>
#include <linux/writeback.h>
#include <linux/buffer_head.h>
#include <linux/workqueue.h>
#include <linux/kthread.h>
#include <linux/freezer.h>
#include <linux/crc32c.h>
#include <linux/slab.h>
#include <linux/migrate.h>
#include <linux/ratelimit.h>
#include <asm/unaligned.h>
#include "compat.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "btrfs_inode.h"
#include "volumes.h"
#include "print-tree.h"
#include "async-thread.h"
#include "locking.h"
#include "tree-log.h"
#include "free-space-cache.h"
#include "inode-map.h"
static struct extent_io_ops btree_extent_io_ops;
static void end_workqueue_fn(struct btrfs_work *work);
static void free_fs_root(struct btrfs_root *root);
static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
int read_only);
static int btrfs_destroy_ordered_operations(struct btrfs_root *root);
static int btrfs_destroy_ordered_extents(struct btrfs_root *root);
static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
struct btrfs_root *root);
static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t);
static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root);
static int btrfs_destroy_marked_extents(struct btrfs_root *root,
struct extent_io_tree *dirty_pages,
int mark);
static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
struct extent_io_tree *pinned_extents);
static int btrfs_cleanup_transaction(struct btrfs_root *root);
/*
* end_io_wq structs are used to do processing in task context when an IO is
* complete. This is used during reads to verify checksums, and it is used
* by writes to insert metadata for new file extents after IO is complete.
*/
struct end_io_wq { struct bio *bio;
bio_end_io_t *end_io;
void *private;
struct btrfs_fs_info *info;
int error;
int metadata;
struct list_head list;
struct btrfs_work work;
};
/*
* async submit bios are used to offload expensive checksumming
* onto the worker threads. They checksum file and metadata bios
* just before they are sent down the IO stack.
*/
struct async_submit_bio {
struct inode *inode;
struct bio *bio;
struct list_head list;
extent_submit_bio_hook_t *submit_bio_start;
extent_submit_bio_hook_t *submit_bio_done;
int rw;
int mirror_num;
unsigned long bio_flags;
/*
* bio_offset is optional, can be used if the pages in the bio
* can't tell us where in the file the bio should go
*/
u64 bio_offset;
struct btrfs_work work;
};
/*
* Lockdep class keys for extent_buffer->lock's in this root. For a given
* eb, the lockdep key is determined by the btrfs_root it belongs to and
* the level the eb occupies in the tree.
*
* Different roots are used for different purposes and may nest inside each
* other and they require separate keysets. As lockdep keys should be
* static, assign keysets according to the purpose of the root as indicated
* by btrfs_root->objectid. This ensures that all special purpose roots
* have separate keysets.
*
* Lock-nesting across peer nodes is always done with the immediate parent
* node locked thus preventing deadlock. As lockdep doesn't know this, use
* subclass to avoid triggering lockdep warning in such cases.
*
* The key is set by the readpage_end_io_hook after the buffer has passed
* csum validation but before the pages are unlocked. It is also set by
* btrfs_init_new_buffer on freshly allocated blocks.
*
* We also add a check to make sure the highest level of the tree is the
* same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code
* needs update as well.
*/
#ifdef CONFIG_DEBUG_LOCK_ALLOC
# if BTRFS_MAX_LEVEL != 8
# error
# endif
static struct btrfs_lockdep_keyset {
u64 id; /* root objectid */
const char *name_stem; /* lock name stem */
char names[BTRFS_MAX_LEVEL + 1][20];
struct lock_class_key keys[BTRFS_MAX_LEVEL + 1];
} btrfs_lockdep_keysets[] = {
{ .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" },
{ .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" },
{ .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" },
{ .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" }, { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" },
{ .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" },
{ .id = BTRFS_ORPHAN_OBJECTID, .name_stem = "orphan" },
{ .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" },
{ .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" },
{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" },
{ .id = 0, .name_stem = "tree" },
};
void __init btrfs_init_lockdep(void)
{
int i, j;
/* initialize lockdep class names */
for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) {
struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i];
for (j = 0; j < ARRAY_SIZE(ks->names); j++)
snprintf(ks->names[j], sizeof(ks->names[j]),
"btrfs-%s-%02d", ks->name_stem, j);
}
}
void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb,
int level)
{
struct btrfs_lockdep_keyset *ks;
BUG_ON(level >= ARRAY_SIZE(ks->keys));
/* find the matching keyset, id 0 is the default entry */
for (ks = btrfs_lockdep_keysets; ks->id; ks++)
if (ks->id == objectid)
break;
lockdep_set_class_and_name(&eb->lock,
&ks->keys[level], ks->names[level]);
}
#endif
/*
* extents on the btree inode are pretty simple, there's one extent
* that covers the entire device
*/
static struct extent_map *btree_get_extent(struct inode *inode,
struct page *page, size_t pg_offset, u64 start, u64 len,
int create)
{
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
struct extent_map *em;
int ret;
read_lock(&em_tree->lock);
em = lookup_extent_mapping(em_tree, start, len);
if (em) {
em->bdev =
BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
read_unlock(&em_tree->lock);
goto out;
}
read_unlock(&em_tree->lock);
em = alloc_extent_map();
if (!em) {
em = ERR_PTR(-ENOMEM);
goto out;
}
em->start = 0;
em->len = (u64)-1; em->block_len = (u64)-1;
em->block_start = 0;
em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
write_lock(&em_tree->lock);
ret = add_extent_mapping(em_tree, em);
if (ret == -EEXIST) {
u64 failed_start = em->start;
u64 failed_len = em->len;
free_extent_map(em);
em = lookup_extent_mapping(em_tree, start, len);
if (em) {
ret = 0;
} else {
em = lookup_extent_mapping(em_tree, failed_start,
failed_len);
ret = -EIO;
}
} else if (ret) {
free_extent_map(em);
em = NULL;
}
write_unlock(&em_tree->lock);
if (ret)
em = ERR_PTR(ret);
out:
return em;
}
u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
{
return crc32c(seed, data, len);
}
void btrfs_csum_final(u32 crc, char *result)
{
put_unaligned_le32(~crc, result);
}
/*
* compute the csum for a btree block, and either verify it or write it
* into the csum field of the block.
*/
static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
int verify)
{
u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
char *result = NULL;
unsigned long len;
unsigned long cur_len;
unsigned long offset = BTRFS_CSUM_SIZE;
char *kaddr;
unsigned long map_start;
unsigned long map_len;
int err;
u32 crc = ~(u32)0;
unsigned long inline_result;
len = buf->len - offset;
while (len > 0) {
err = map_private_extent_buffer(buf, offset, 32,
&kaddr, &map_start, &map_len);
if (err)
return 1;
cur_len = min(len, map_len - (offset - map_start));
crc = btrfs_csum_data(root, kaddr + offset - map_start,
crc, cur_len);
len -= cur_len; offset += cur_len;
}
if (csum_size > sizeof(inline_result)) {
result = kzalloc(csum_size * sizeof(char), GFP_NOFS);
if (!result)
return 1;
} else {
result = (char *)&inline_result;
}
btrfs_csum_final(crc, result);
if (verify) {
if (memcmp_extent_buffer(buf, result, 0, csum_size)) {
u32 val;
u32 found = 0;
memcpy(&found, result, csum_size);
read_extent_buffer(buf, &val, 0, csum_size);
printk_ratelimited(KERN_INFO "btrfs: %s checksum verify "
"failed on %llu wanted %X found %X "
"level %d\n",
root->fs_info->sb->s_id,
(unsigned long long)buf->start, val, found,
btrfs_header_level(buf));
if (result != (char *)&inline_result)
kfree(result);
return 1;
}
} else {
write_extent_buffer(buf, result, 0, csum_size);
}
if (result != (char *)&inline_result)
kfree(result);
return 0;
}
/*
* we can't consider a given block up to date unless the transid of the
* block matches the transid in the parent node's pointer. This is how we
* detect blocks that either didn't get written at all or got written
* in the wrong place.
*/
static int verify_parent_transid(struct extent_io_tree *io_tree,
struct extent_buffer *eb, u64 parent_transid)
{
struct extent_state *cached_state = NULL;
int ret;
if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
return 0;
lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
0, &cached_state, GFP_NOFS);
if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
btrfs_header_generation(eb) == parent_transid) {
ret = 0;
goto out;
}
printk_ratelimited("parent transid verify failed on %llu wanted %llu "
"found %llu\n",
(unsigned long long)eb->start,
(unsigned long long)parent_transid,
(unsigned long long)btrfs_header_generation(eb));
ret = 1;
clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
out:
unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
&cached_state, GFP_NOFS);
return ret;}
/*
* helper to read a given tree block, doing retries as required when
* the checksums don't match and we have alternate mirrors to try.
*/
static int btree_read_extent_buffer_pages(struct btrfs_root *root,
struct extent_buffer *eb,
u64 start, u64 parent_transid)
{
struct extent_io_tree *io_tree;
int ret;
int num_copies = 0;
int mirror_num = 0;
clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
while (1) {
ret = read_extent_buffer_pages(io_tree, eb, start,
WAIT_COMPLETE,
btree_get_extent, mirror_num);
if (!ret &&
!verify_parent_transid(io_tree, eb, parent_transid))
return ret;
/*
* This buffer's crc is fine, but its contents are corrupted, so
* there is no reason to read the other copies, they won't be
* any less wrong.
*/
if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
return ret;
num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
eb->start, eb->len);
if (num_copies == 1)
return ret;
mirror_num++;
if (mirror_num > num_copies)
return ret;
}
return -EIO;
}
/*
* checksum a dirty tree block before IO. This has extra checks to make sure
* we only fill in the checksum field in the first page of a multi-page block
*/
static int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
{
struct extent_io_tree *tree;
u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
u64 found_start;
unsigned long len;
struct extent_buffer *eb;
int ret;
tree = &BTRFS_I(page->mapping->host)->io_tree;
if (page->private == EXTENT_PAGE_PRIVATE) {
WARN_ON(1);
goto out;
}
if (!page->private) {
WARN_ON(1);
goto out;
}
len = page->private >> 2; WARN_ON(len == 0);
eb = alloc_extent_buffer(tree, start, len, page);
if (eb == NULL) {
WARN_ON(1);
goto out;
}
ret = btree_read_extent_buffer_pages(root, eb, start + PAGE_CACHE_SIZE,
btrfs_header_generation(eb));
BUG_ON(ret);
WARN_ON(!btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN));
found_start = btrfs_header_bytenr(eb);
if (found_start != start) {
WARN_ON(1);
goto err;
}
if (eb->first_page != page) {
WARN_ON(1);
goto err;
}
if (!PageUptodate(page)) {
WARN_ON(1);
goto err;
}
csum_tree_block(root, eb, 0);
err:
free_extent_buffer(eb);
out:
return 0;
}
static int check_tree_block_fsid(struct btrfs_root *root,
struct extent_buffer *eb)
{
struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
u8 fsid[BTRFS_UUID_SIZE];
int ret = 1;
read_extent_buffer(eb, fsid, (unsigned long)btrfs_header_fsid(eb),
BTRFS_FSID_SIZE);
while (fs_devices) {
if (!memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE)) {
ret = 0;
break;
}
fs_devices = fs_devices->seed;
}
return ret;
}
#define CORRUPT(reason, eb, root, slot) \
printk(KERN_CRIT "btrfs: corrupt leaf, %s: block=%llu," \
"root=%llu, slot=%d\n", reason, \
(unsigned long long)btrfs_header_bytenr(eb), \
(unsigned long long)root->objectid, slot)
static noinline int check_leaf(struct btrfs_root *root,
struct extent_buffer *leaf)
{
struct btrfs_key key;
struct btrfs_key leaf_key;
u32 nritems = btrfs_header_nritems(leaf);
int slot;
if (nritems == 0)
return 0;
/* Check the 0 item */
if (btrfs_item_offset_nr(leaf, 0) + btrfs_item_size_nr(leaf, 0) != BTRFS_LEAF_DATA_SIZE(root)) {
CORRUPT("invalid item offset size pair", leaf, root, 0);
return -EIO;
}
/*
* Check to make sure each items keys are in the correct order and their
* offsets make sense. We only have to loop through nritems-1 because
* we check the current slot against the next slot, which verifies the
* next slot's offset+size makes sense and that the current's slot
* offset is correct.
*/
for (slot = 0; slot < nritems - 1; slot++) {
btrfs_item_key_to_cpu(leaf, &leaf_key, slot);
btrfs_item_key_to_cpu(leaf, &key, slot + 1);
/* Make sure the keys are in the right order */
if (btrfs_comp_cpu_keys(&leaf_key, &key) >= 0) {
CORRUPT("bad key order", leaf, root, slot);
return -EIO;
}
/*
* Make sure the offset and ends are right, remember that the
* item data starts at the end of the leaf and grows towards the
* front.
*/
if (btrfs_item_offset_nr(leaf, slot) !=
btrfs_item_end_nr(leaf, slot + 1)) {
CORRUPT("slot offset bad", leaf, root, slot);
return -EIO;
}
/*
* Check to make sure that we don't point outside of the leaf,
* just incase all the items are consistent to eachother, but
* all point outside of the leaf.
*/
if (btrfs_item_end_nr(leaf, slot) >
BTRFS_LEAF_DATA_SIZE(root)) {
CORRUPT("slot end outside of leaf", leaf, root, slot);
return -EIO;
}
}
return 0;
}
static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
struct extent_state *state)
{
struct extent_io_tree *tree;
u64 found_start;
int found_level;
unsigned long len;
struct extent_buffer *eb;
struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
int ret = 0;
tree = &BTRFS_I(page->mapping->host)->io_tree;
if (page->private == EXTENT_PAGE_PRIVATE)
goto out;
if (!page->private)
goto out;
len = page->private >> 2;
WARN_ON(len == 0);
eb = alloc_extent_buffer(tree, start, len, page);
if (eb == NULL) { ret = -EIO;
goto out;
}
found_start = btrfs_header_bytenr(eb);
if (found_start != start) {
printk_ratelimited(KERN_INFO "btrfs bad tree block start "
"%llu %llu\n",
(unsigned long long)found_start,
(unsigned long long)eb->start);
ret = -EIO;
goto err;
}
if (eb->first_page != page) {
printk(KERN_INFO "btrfs bad first page %lu %lu\n",
eb->first_page->index, page->index);
WARN_ON(1);
ret = -EIO;
goto err;
}
if (check_tree_block_fsid(root, eb)) {
printk_ratelimited(KERN_INFO "btrfs bad fsid on block %llu\n",
(unsigned long long)eb->start);
ret = -EIO;
goto err;
}
found_level = btrfs_header_level(eb);
btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb),
eb, found_level);
ret = csum_tree_block(root, eb, 1);
if (ret) {
ret = -EIO;
goto err;
}
/*
* If this is a leaf block and it is corrupt, set the corrupt bit so
* that we don't try and read the other copies of this block, just
* return -EIO.
*/
if (found_level == 0 && check_leaf(root, eb)) {
set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
ret = -EIO;
}
end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
end = eb->start + end - 1;
err:
if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
btree_readahead_hook(root, eb, eb->start, ret);
}
free_extent_buffer(eb);
out:
return ret;
}
static int btree_io_failed_hook(struct bio *failed_bio,
struct page *page, u64 start, u64 end,
int mirror_num, struct extent_state *state)
{
struct extent_io_tree *tree;
unsigned long len;
struct extent_buffer *eb;
struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
tree = &BTRFS_I(page->mapping->host)->io_tree; if (page->private == EXTENT_PAGE_PRIVATE)
goto out;
if (!page->private)
goto out;
len = page->private >> 2;
WARN_ON(len == 0);
eb = alloc_extent_buffer(tree, start, len, page);
if (eb == NULL)
goto out;
if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
btree_readahead_hook(root, eb, eb->start, -EIO);
}
free_extent_buffer(eb);
out:
return -EIO; /* we fixed nothing */
}
static void end_workqueue_bio(struct bio *bio, int err)
{
struct end_io_wq *end_io_wq = bio->bi_private;
struct btrfs_fs_info *fs_info;
fs_info = end_io_wq->info;
end_io_wq->error = err;
end_io_wq->work.func = end_workqueue_fn;
end_io_wq->work.flags = 0;
if (bio->bi_rw & REQ_WRITE) {
if (end_io_wq->metadata == 1)
btrfs_queue_worker(&fs_info->endio_meta_write_workers,
&end_io_wq->work);
else if (end_io_wq->metadata == 2)
btrfs_queue_worker(&fs_info->endio_freespace_worker,
&end_io_wq->work);
else
btrfs_queue_worker(&fs_info->endio_write_workers,
&end_io_wq->work);
} else {
if (end_io_wq->metadata)
btrfs_queue_worker(&fs_info->endio_meta_workers,
&end_io_wq->work);
else
btrfs_queue_worker(&fs_info->endio_workers,
&end_io_wq->work);
}
}
/*
* For the metadata arg you want
*
* 0 - if data
* 1 - if normal metadta
* 2 - if writing to the free space cache area
*/
int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
int metadata)
{
struct end_io_wq *end_io_wq;
end_io_wq = kmalloc(sizeof(*end_io_wq), GFP_NOFS);
if (!end_io_wq)
return -ENOMEM;
end_io_wq->private = bio->bi_private;
end_io_wq->end_io = bio->bi_end_io;
end_io_wq->info = info; end_io_wq->error = 0;
end_io_wq->bio = bio;
end_io_wq->metadata = metadata;
bio->bi_private = end_io_wq;
bio->bi_end_io = end_workqueue_bio;
return 0;
}
unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info)
{
unsigned long limit = min_t(unsigned long,
info->workers.max_workers,
info->fs_devices->open_devices);
return 256 * limit;
}
static void run_one_async_start(struct btrfs_work *work)
{
struct async_submit_bio *async;
async = container_of(work, struct async_submit_bio, work);
async->submit_bio_start(async->inode, async->rw, async->bio,
async->mirror_num, async->bio_flags,
async->bio_offset);
}
static void run_one_async_done(struct btrfs_work *work)
{
struct btrfs_fs_info *fs_info;
struct async_submit_bio *async;
int limit;
async = container_of(work, struct async_submit_bio, work);
fs_info = BTRFS_I(async->inode)->root->fs_info;
limit = btrfs_async_submit_limit(fs_info);
limit = limit * 2 / 3;
atomic_dec(&fs_info->nr_async_submits);
if (atomic_read(&fs_info->nr_async_submits) < limit &&
waitqueue_active(&fs_info->async_submit_wait))
wake_up(&fs_info->async_submit_wait);
async->submit_bio_done(async->inode, async->rw, async->bio,
async->mirror_num, async->bio_flags,
async->bio_offset);
}
static void run_one_async_free(struct btrfs_work *work)
{
struct async_submit_bio *async;
async = container_of(work, struct async_submit_bio, work);
kfree(async);
}
int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
int rw, struct bio *bio, int mirror_num,
unsigned long bio_flags,
u64 bio_offset,
extent_submit_bio_hook_t *submit_bio_start,
extent_submit_bio_hook_t *submit_bio_done)
{
struct async_submit_bio *async;
async = kmalloc(sizeof(*async), GFP_NOFS);
if (!async)
return -ENOMEM;
async->inode = inode;
async->rw = rw;
async->bio = bio;
async->mirror_num = mirror_num;
async->submit_bio_start = submit_bio_start;
async->submit_bio_done = submit_bio_done;
async->work.func = run_one_async_start;
async->work.ordered_func = run_one_async_done;
async->work.ordered_free = run_one_async_free;
async->work.flags = 0;
async->bio_flags = bio_flags;
async->bio_offset = bio_offset;
atomic_inc(&fs_info->nr_async_submits);
if (rw & REQ_SYNC)
btrfs_set_work_high_prio(&async->work);
btrfs_queue_worker(&fs_info->workers, &async->work);
while (atomic_read(&fs_info->async_submit_draining) &&
atomic_read(&fs_info->nr_async_submits)) {
wait_event(fs_info->async_submit_wait,
(atomic_read(&fs_info->nr_async_submits) == 0));
}
return 0;
}
static int btree_csum_one_bio(struct bio *bio)
{
struct bio_vec *bvec = bio->bi_io_vec;
int bio_index = 0;
struct btrfs_root *root;
WARN_ON(bio->bi_vcnt <= 0);
while (bio_index < bio->bi_vcnt) {
root = BTRFS_I(bvec->bv_page->mapping->host)->root;
csum_dirty_buffer(root, bvec->bv_page);
bio_index++;
bvec++;
}
return 0;
}
static int __btree_submit_bio_start(struct inode *inode, int rw,
struct bio *bio, int mirror_num,
unsigned long bio_flags,
u64 bio_offset)
{
/*
* when we're called for a write, we're already in the async
* submission context. Just jump into btrfs_map_bio
*/
btree_csum_one_bio(bio);
return 0;
}
static int __btree_submit_bio_done(struct inode *inode, int rw, struct bio *bio,
int mirror_num, unsigned long bio_flags,
u64 bio_offset)
{
/*
* when we're called for a write, we're already in the async
* submission context. Just jump into btrfs_map_bio
*/
return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio, mirror_num, 1);}
static int btree_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
int mirror_num, unsigned long bio_flags,
u64 bio_offset)
{
int ret;
ret = btrfs_bio_wq_end_io(BTRFS_I(inode)->root->fs_info,
bio, 1);
BUG_ON(ret);
if (!(rw & REQ_WRITE)) {
/*
* called for a read, do the setup so that checksum validation
* can happen in the async kernel threads
*/
return btrfs_map_bio(BTRFS_I(inode)->root, rw, bio,
mirror_num, 0);
}
/*
* kthread helpers are used to submit writes so that checksumming
* can happen in parallel across all CPUs
*/
return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
inode, rw, bio, mirror_num, 0,
bio_offset,
__btree_submit_bio_start,
__btree_submit_bio_done);
}
#ifdef CONFIG_MIGRATION
static int btree_migratepage(struct address_space *mapping,
struct page *newpage, struct page *page)
{
/*
* we can't safely write a btree page from here,
* we haven't done the locking hook
*/
if (PageDirty(page))
return -EAGAIN;
/*
* Buffers may be managed in a filesystem specific way.
* We must have no buffers or drop them.
*/
if (page_has_private(page) &&
!try_to_release_page(page, GFP_KERNEL))
return -EAGAIN;
return migrate_page(mapping, newpage, page);
}
#endif
static int btree_writepage(struct page *page, struct writeback_control *wbc)
{
struct extent_io_tree *tree;
struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
struct extent_buffer *eb;
int was_dirty;
tree = &BTRFS_I(page->mapping->host)->io_tree;
if (!(current->flags & PF_MEMALLOC)) {
return extent_write_full_page(tree, page,
btree_get_extent, wbc);
}
redirty_page_for_writepage(wbc, page);
eb = btrfs_find_tree_block(root, page_offset(page), PAGE_CACHE_SIZE);
WARN_ON(!eb);
was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
if (!was_dirty) {
spin_lock(&root->fs_info->delalloc_lock);
root->fs_info->dirty_metadata_bytes += PAGE_CACHE_SIZE;
spin_unlock(&root->fs_info->delalloc_lock);
}
free_extent_buffer(eb);
unlock_page(page);
return 0;
}
static int btree_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
struct extent_io_tree *tree;
tree = &BTRFS_I(mapping->host)->io_tree;
if (wbc->sync_mode == WB_SYNC_NONE) {
struct btrfs_root *root = BTRFS_I(mapping->host)->root;
u64 num_dirty;
unsigned long thresh = 32 * 1024 * 1024;
if (wbc->for_kupdate)
return 0;
/* this is a bit racy, but that's ok */
num_dirty = root->fs_info->dirty_metadata_bytes;
if (num_dirty < thresh)
return 0;
}
return extent_writepages(tree, mapping, btree_get_extent, wbc);
}
static int btree_readpage(struct file *file, struct page *page)
{
struct extent_io_tree *tree;
tree = &BTRFS_I(page->mapping->host)->io_tree;
return extent_read_full_page(tree, page, btree_get_extent, 0);
}
static int btree_releasepage(struct page *page, gfp_t gfp_flags)
{
struct extent_io_tree *tree;
struct extent_map_tree *map;
int ret;
if (PageWriteback(page) || PageDirty(page))
return 0;
tree = &BTRFS_I(page->mapping->host)->io_tree;
map = &BTRFS_I(page->mapping->host)->extent_tree;
ret = try_release_extent_state(map, tree, page, gfp_flags);
if (!ret)
return 0;
ret = try_release_extent_buffer(tree, page);
if (ret == 1) {
ClearPagePrivate(page);
set_page_private(page, 0);
page_cache_release(page);
}
return ret;
}
static void btree_invalidatepage(struct page *page, unsigned long offset)
{
struct extent_io_tree *tree;
tree = &BTRFS_I(page->mapping->host)->io_tree; extent_invalidatepage(tree, page, offset);
btree_releasepage(page, GFP_NOFS);
if (PagePrivate(page)) {
printk(KERN_WARNING "btrfs warning page private not zero "
"on page %llu\n", (unsigned long long)page_offset(page));
ClearPagePrivate(page);
set_page_private(page, 0);
page_cache_release(page);
}
}
static const struct address_space_operations btree_aops = {
.readpage = btree_readpage,
.writepage = btree_writepage,
.writepages = btree_writepages,
.releasepage = btree_releasepage,
.invalidatepage = btree_invalidatepage,
#ifdef CONFIG_MIGRATION
.migratepage = btree_migratepage,
#endif
};
int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
u64 parent_transid)
{
struct extent_buffer *buf = NULL;
struct inode *btree_inode = root->fs_info->btree_inode;
int ret = 0;
buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
if (!buf)
return 0;
read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
buf, 0, WAIT_NONE, btree_get_extent, 0);
free_extent_buffer(buf);
return ret;
}
int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
int mirror_num, struct extent_buffer **eb)
{
struct extent_buffer *buf = NULL;
struct inode *btree_inode = root->fs_info->btree_inode;
struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
int ret;
buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
if (!buf)
return 0;
set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
btree_get_extent, mirror_num);
if (ret) {
free_extent_buffer(buf);
return ret;
}
if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
free_extent_buffer(buf);
return -EIO;
} else if (extent_buffer_uptodate(io_tree, buf, NULL)) {
*eb = buf;
} else {
free_extent_buffer(buf);
}
return 0;
}
struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize)
{
struct inode *btree_inode = root->fs_info->btree_inode;
struct extent_buffer *eb;
eb = find_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
bytenr, blocksize);
return eb;
}
struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize)
{
struct inode *btree_inode = root->fs_info->btree_inode;
struct extent_buffer *eb;
eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->io_tree,
bytenr, blocksize, NULL);
return eb;
}
int btrfs_write_tree_block(struct extent_buffer *buf)
{
return filemap_fdatawrite_range(buf->first_page->mapping, buf->start,
buf->start + buf->len - 1);
}
int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
{
return filemap_fdatawait_range(buf->first_page->mapping,
buf->start, buf->start + buf->len - 1);
}
struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
u32 blocksize, u64 parent_transid)
{
struct extent_buffer *buf = NULL;
int ret;
buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
if (!buf)
return NULL;
ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
if (ret == 0)
set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
return buf;
}
int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf)
{
struct inode *btree_inode = root->fs_info->btree_inode;
if (btrfs_header_generation(buf) ==
root->fs_info->running_transaction->transid) {
btrfs_assert_tree_locked(buf);
if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) {
spin_lock(&root->fs_info->delalloc_lock);
if (root->fs_info->dirty_metadata_bytes >= buf->len)
root->fs_info->dirty_metadata_bytes -= buf->len;
else
WARN_ON(1);
spin_unlock(&root->fs_info->delalloc_lock);
}
/* ugh, clear_extent_buffer_dirty needs to lock the page */ btrfs_set_lock_blocking(buf);
clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
buf);
}
return 0;
}
static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
u32 stripesize, struct btrfs_root *root,
struct btrfs_fs_info *fs_info,
u64 objectid)
{
root->node = NULL;
root->commit_root = NULL;
root->sectorsize = sectorsize;
root->nodesize = nodesize;
root->leafsize = leafsize;
root->stripesize = stripesize;
root->ref_cows = 0;
root->track_dirty = 0;
root->in_radix = 0;
root->orphan_item_inserted = 0;
root->orphan_cleanup_state = 0;
root->fs_info = fs_info;
root->objectid = objectid;
root->last_trans = 0;
root->highest_objectid = 0;
root->name = NULL;
root->inode_tree = RB_ROOT;
INIT_RADIX_TREE(&root->delayed_nodes_tree, GFP_ATOMIC);
root->block_rsv = NULL;
root->orphan_block_rsv = NULL;
INIT_LIST_HEAD(&root->dirty_list);
INIT_LIST_HEAD(&root->orphan_list);
INIT_LIST_HEAD(&root->root_list);
spin_lock_init(&root->orphan_lock);
spin_lock_init(&root->inode_lock);
spin_lock_init(&root->accounting_lock);
mutex_init(&root->objectid_mutex);
mutex_init(&root->log_mutex);
init_waitqueue_head(&root->log_writer_wait);
init_waitqueue_head(&root->log_commit_wait[0]);
init_waitqueue_head(&root->log_commit_wait[1]);
atomic_set(&root->log_commit[0], 0);
atomic_set(&root->log_commit[1], 0);
atomic_set(&root->log_writers, 0);
root->log_batch = 0;
root->log_transid = 0;
root->last_log_commit = 0;
extent_io_tree_init(&root->dirty_log_pages,
fs_info->btree_inode->i_mapping);
memset(&root->root_key, 0, sizeof(root->root_key));
memset(&root->root_item, 0, sizeof(root->root_item));
memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
memset(&root->root_kobj, 0, sizeof(root->root_kobj));
root->defrag_trans_start = fs_info->generation;
init_completion(&root->kobj_unregister);
root->defrag_running = 0;
root->root_key.objectid = objectid;
root->anon_dev = 0;
return 0;
}
static int find_and_setup_root(struct btrfs_root *tree_root,
struct btrfs_fs_info *fs_info,
u64 objectid,
struct btrfs_root *root){
int ret;
u32 blocksize;
u64 generation;
__setup_root(tree_root->nodesize, tree_root->leafsize,
tree_root->sectorsize, tree_root->stripesize,
root, fs_info, objectid);
ret = btrfs_find_last_root(tree_root, objectid,
&root->root_item, &root->root_key);
if (ret > 0)
return -ENOENT;
BUG_ON(ret);
generation = btrfs_root_generation(&root->root_item);
blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
root->commit_root = NULL;
root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
blocksize, generation);
if (!root->node || !btrfs_buffer_uptodate(root->node, generation)) {
free_extent_buffer(root->node);
root->node = NULL;
return -EIO;
}
root->commit_root = btrfs_root_node(root);
return 0;
}
static struct btrfs_root *alloc_log_tree(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root;
struct btrfs_root *tree_root = fs_info->tree_root;
struct extent_buffer *leaf;
root = kzalloc(sizeof(*root), GFP_NOFS);
if (!root)
return ERR_PTR(-ENOMEM);
__setup_root(tree_root->nodesize, tree_root->leafsize,
tree_root->sectorsize, tree_root->stripesize,
root, fs_info, BTRFS_TREE_LOG_OBJECTID);
root->root_key.objectid = BTRFS_TREE_LOG_OBJECTID;
root->root_key.type = BTRFS_ROOT_ITEM_KEY;
root->root_key.offset = BTRFS_TREE_LOG_OBJECTID;
/*
* log trees do not get reference counted because they go away
* before a real commit is actually done. They do store pointers
* to file data extents, and those reference counts still get
* updated (along with back refs to the log tree).
*/
root->ref_cows = 0;
leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
BTRFS_TREE_LOG_OBJECTID, NULL, 0, 0, 0);
if (IS_ERR(leaf)) {
kfree(root);
return ERR_CAST(leaf);
}
memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
btrfs_set_header_bytenr(leaf, leaf->start);
btrfs_set_header_generation(leaf, trans->transid);
btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
btrfs_set_header_owner(leaf, BTRFS_TREE_LOG_OBJECTID);
root->node = leaf;
write_extent_buffer(root->node, root->fs_info->fsid,
(unsigned long)btrfs_header_fsid(root->node), BTRFS_FSID_SIZE);
btrfs_mark_buffer_dirty(root->node);
btrfs_tree_unlock(root->node);
return root;
}
int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info)
{
struct btrfs_root *log_root;
log_root = alloc_log_tree(trans, fs_info);
if (IS_ERR(log_root))
return PTR_ERR(log_root);
WARN_ON(fs_info->log_root_tree);
fs_info->log_root_tree = log_root;
return 0;
}
int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
struct btrfs_root *log_root;
struct btrfs_inode_item *inode_item;
log_root = alloc_log_tree(trans, root->fs_info);
if (IS_ERR(log_root))
return PTR_ERR(log_root);
log_root->last_trans = trans->transid;
log_root->root_key.offset = root->root_key.objectid;
inode_item = &log_root->root_item.inode;
inode_item->generation = cpu_to_le64(1);
inode_item->size = cpu_to_le64(3);
inode_item->nlink = cpu_to_le32(1);
inode_item->nbytes = cpu_to_le64(root->leafsize);
inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
btrfs_set_root_node(&log_root->root_item, log_root->node);
WARN_ON(root->log_root);
root->log_root = log_root;
root->log_transid = 0;
root->last_log_commit = 0;
return 0;
}
struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
struct btrfs_key *location)
{
struct btrfs_root *root;
struct btrfs_fs_info *fs_info = tree_root->fs_info;
struct btrfs_path *path;
struct extent_buffer *l;
u64 generation;
u32 blocksize;
int ret = 0;
root = kzalloc(sizeof(*root), GFP_NOFS);
if (!root)
return ERR_PTR(-ENOMEM);
if (location->offset == (u64)-1) {
ret = find_and_setup_root(tree_root, fs_info,
location->objectid, root);
if (ret) {
kfree(root);
return ERR_PTR(ret);
}
goto out; }
__setup_root(tree_root->nodesize, tree_root->leafsize,
tree_root->sectorsize, tree_root->stripesize,
root, fs_info, location->objectid);
path = btrfs_alloc_path();
if (!path) {
kfree(root);
return ERR_PTR(-ENOMEM);
}
ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
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));
}
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);
out:
if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
root->ref_cows = 1;
btrfs_check_and_init_root_item(&root->root_item);
}
return root;
}
struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
struct btrfs_key *location)
{
struct btrfs_root *root;
int ret;
if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
return fs_info->tree_root;
if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
return fs_info->extent_root;
if (location->objectid == BTRFS_CHUNK_TREE_OBJECTID)
return fs_info->chunk_root;
if (location->objectid == BTRFS_DEV_TREE_OBJECTID)
return fs_info->dev_root;
if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
return fs_info->csum_root;
again:
spin_lock(&fs_info->fs_roots_radix_lock);
root = radix_tree_lookup(&fs_info->fs_roots_radix,
(unsigned long)location->objectid);
spin_unlock(&fs_info->fs_roots_radix_lock);
if (root)
return root;
root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
if (IS_ERR(root))
return root;
root->free_ino_ctl = kzalloc(sizeof(*root->free_ino_ctl), GFP_NOFS);
root->free_ino_pinned = kzalloc(sizeof(*root->free_ino_pinned),
GFP_NOFS);
if (!root->free_ino_pinned || !root->free_ino_ctl) {
ret = -ENOMEM;
goto fail;
}
btrfs_init_free_ino_ctl(root);
mutex_init(&root->fs_commit_mutex);
spin_lock_init(&root->cache_lock);
init_waitqueue_head(&root->cache_wait);
ret = get_anon_bdev(&root->anon_dev);
if (ret)
goto fail;
if (btrfs_root_refs(&root->root_item) == 0) {
ret = -ENOENT;
goto fail;
}
ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
if (ret < 0)
goto fail;
if (ret == 0)
root->orphan_item_inserted = 1;
ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
if (ret)
goto fail;
spin_lock(&fs_info->fs_roots_radix_lock);
ret = radix_tree_insert(&fs_info->fs_roots_radix,
(unsigned long)root->root_key.objectid,
root);
if (ret == 0)
root->in_radix = 1;
spin_unlock(&fs_info->fs_roots_radix_lock);
radix_tree_preload_end();
if (ret) {
if (ret == -EEXIST) {
free_fs_root(root);
goto again;
}
goto fail;
}
ret = btrfs_find_dead_roots(fs_info->tree_root,
root->root_key.objectid);
WARN_ON(ret);
return root;
fail:
free_fs_root(root);
return ERR_PTR(ret);
}
static int btrfs_congested_fn(void *congested_data, int bdi_bits)
{
struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data;
int ret = 0;
struct btrfs_device *device;
struct backing_dev_info *bdi;
rcu_read_lock();
list_for_each_entry_rcu(device, &info->fs_devices->devices, dev_list) {
if (!device->bdev)
continue;
bdi = blk_get_backing_dev_info(device->bdev); if (bdi && bdi_congested(bdi, bdi_bits)) {
ret = 1;
break;
}
}
rcu_read_unlock();
return ret;
}
/*
* If this fails, caller must call bdi_destroy() to get rid of the
* bdi again.
*/
static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
{
int err;
bdi->capabilities = BDI_CAP_MAP_COPY;
err = bdi_setup_and_register(bdi, "btrfs", BDI_CAP_MAP_COPY);
if (err)
return err;
bdi->ra_pages = default_backing_dev_info.ra_pages;
bdi->congested_fn = btrfs_congested_fn;
bdi->congested_data = info;
return 0;
}
static int bio_ready_for_csum(struct bio *bio)
{
u64 length = 0;
u64 buf_len = 0;
u64 start = 0;
struct page *page;
struct extent_io_tree *io_tree = NULL;
struct bio_vec *bvec;
int i;
int ret;
bio_for_each_segment(bvec, bio, i) {
page = bvec->bv_page;
if (page->private == EXTENT_PAGE_PRIVATE) {
length += bvec->bv_len;
continue;
}
if (!page->private) {
length += bvec->bv_len;
continue;
}
length = bvec->bv_len;
buf_len = page->private >> 2;
start = page_offset(page) + bvec->bv_offset;
io_tree = &BTRFS_I(page->mapping->host)->io_tree;
}
/* are we fully contained in this bio? */
if (buf_len <= length)
return 1;
ret = extent_range_uptodate(io_tree, start + length,
start + buf_len - 1);
return ret;
}
/*
* called by the kthread helper functions to finally call the bio end_io
* functions. This is where read checksum verification actually happens
*/
static void end_workqueue_fn(struct btrfs_work *work)
{
struct bio *bio; struct end_io_wq *end_io_wq;
struct btrfs_fs_info *fs_info;
int error;
end_io_wq = container_of(work, struct end_io_wq, work);
bio = end_io_wq->bio;
fs_info = end_io_wq->info;
/* metadata bio reads are special because the whole tree block must
* be checksummed at once. This makes sure the entire block is in
* ram and up to date before trying to verify things. For
* blocksize <= pagesize, it is basically a noop
*/
if (!(bio->bi_rw & REQ_WRITE) && end_io_wq->metadata &&
!bio_ready_for_csum(bio)) {
btrfs_queue_worker(&fs_info->endio_meta_workers,
&end_io_wq->work);
return;
}
error = end_io_wq->error;
bio->bi_private = end_io_wq->private;
bio->bi_end_io = end_io_wq->end_io;
kfree(end_io_wq);
bio_endio(bio, error);
}
static int cleaner_kthread(void *arg)
{
struct btrfs_root *root = arg;
do {
vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
mutex_trylock(&root->fs_info->cleaner_mutex)) {
btrfs_run_delayed_iputs(root);
btrfs_clean_old_snapshots(root);
mutex_unlock(&root->fs_info->cleaner_mutex);
btrfs_run_defrag_inodes(root->fs_info);
}
if (freezing(current)) {
refrigerator();
} else {
set_current_state(TASK_INTERRUPTIBLE);
if (!kthread_should_stop())
schedule();
__set_current_state(TASK_RUNNING);
}
} while (!kthread_should_stop());
return 0;
}
static int transaction_kthread(void *arg)
{
struct btrfs_root *root = arg;
struct btrfs_trans_handle *trans;
struct btrfs_transaction *cur;
u64 transid;
unsigned long now;
unsigned long delay;
int ret;
do {
delay = HZ * 30;
vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
mutex_lock(&root->fs_info->transaction_kthread_mutex);
spin_lock(&root->fs_info->trans_lock);
cur = root->fs_info->running_transaction; if (!cur) {
spin_unlock(&root->fs_info->trans_lock);
goto sleep;
}
now = get_seconds();
if (!cur->blocked &&
(now < cur->start_time || now - cur->start_time < 30)) {
spin_unlock(&root->fs_info->trans_lock);
delay = HZ * 5;
goto sleep;
}
transid = cur->transid;
spin_unlock(&root->fs_info->trans_lock);
trans = btrfs_join_transaction(root);
BUG_ON(IS_ERR(trans));
if (transid == trans->transid) {
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
} else {
btrfs_end_transaction(trans, root);
}
sleep:
wake_up_process(root->fs_info->cleaner_kthread);
mutex_unlock(&root->fs_info->transaction_kthread_mutex);
if (freezing(current)) {
refrigerator();
} else {
set_current_state(TASK_INTERRUPTIBLE);
if (!kthread_should_stop() &&
!btrfs_transaction_blocked(root->fs_info))
schedule_timeout(delay);
__set_current_state(TASK_RUNNING);
}
} while (!kthread_should_stop());
return 0;
}
/*
* this will find the highest generation in the array of
* root backups. The index of the highest array is returned,
* or -1 if we can't find anything.
*
* We check to make sure the array is valid by comparing the
* generation of the latest root in the array with the generation
* in the super block. If they don't match we pitch it.
*/
static int find_newest_super_backup(struct btrfs_fs_info *info, u64 newest_gen)
{
u64 cur;
int newest_index = -1;
struct btrfs_root_backup *root_backup;
int i;
for (i = 0; i < BTRFS_NUM_BACKUP_ROOTS; i++) {
root_backup = info->super_copy->super_roots + i;
cur = btrfs_backup_tree_root_gen(root_backup);
if (cur == newest_gen)
newest_index = i;
}
/* check to see if we actually wrapped around */
if (newest_index == BTRFS_NUM_BACKUP_ROOTS - 1) {
root_backup = info->super_copy->super_roots;
cur = btrfs_backup_tree_root_gen(root_backup);
if (cur == newest_gen)
newest_index = 0;
} return newest_index;
}
/*
* find the oldest backup so we know where to store new entries
* in the backup array. This will set the backup_root_index
* field in the fs_info struct
*/
static void find_oldest_super_backup(struct btrfs_fs_info *info,
u64 newest_gen)
{
int newest_index = -1;
newest_index = find_newest_super_backup(info, newest_gen);
/* if there was garbage in there, just move along */
if (newest_index == -1) {
info->backup_root_index = 0;
} else {
info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS;
}
}
/*
* copy all the root pointers into the super backup array.
* this will bump the backup pointer by one when it is
* done
*/
static void backup_super_roots(struct btrfs_fs_info *info)
{
int next_backup;
struct btrfs_root_backup *root_backup;
int last_backup;
next_backup = info->backup_root_index;
last_backup = (next_backup + BTRFS_NUM_BACKUP_ROOTS - 1) %
BTRFS_NUM_BACKUP_ROOTS;
/*
* just overwrite the last backup if we're at the same generation
* this happens only at umount
*/
root_backup = info->super_for_commit->super_roots + last_backup;
if (btrfs_backup_tree_root_gen(root_backup) ==
btrfs_header_generation(info->tree_root->node))
next_backup = last_backup;
root_backup = info->super_for_commit->super_roots + next_backup;
/*
* make sure all of our padding and empty slots get zero filled
* regardless of which ones we use today
*/
memset(root_backup, 0, sizeof(*root_backup));
info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;
btrfs_set_backup_tree_root(root_backup, info->tree_root->node->start);
btrfs_set_backup_tree_root_gen(root_backup,
btrfs_header_generation(info->tree_root->node));
btrfs_set_backup_tree_root_level(root_backup,
btrfs_header_level(info->tree_root->node));
btrfs_set_backup_chunk_root(root_backup, info->chunk_root->node->start);
btrfs_set_backup_chunk_root_gen(root_backup,
btrfs_header_generation(info->chunk_root->node));
btrfs_set_backup_chunk_root_level(root_backup,
btrfs_header_level(info->chunk_root->node));
btrfs_set_backup_extent_root(root_backup, info->extent_root->node->start);
btrfs_set_backup_extent_root_gen(root_backup,
btrfs_header_generation(info->extent_root->node));
btrfs_set_backup_extent_root_level(root_backup,
btrfs_header_level(info->extent_root->node));
/*
* we might commit during log recovery, which happens before we set
* the fs_root. Make sure it is valid before we fill it in.
*/
if (info->fs_root && info->fs_root->node) {
btrfs_set_backup_fs_root(root_backup,
info->fs_root->node->start);
btrfs_set_backup_fs_root_gen(root_backup,
btrfs_header_generation(info->fs_root->node));
btrfs_set_backup_fs_root_level(root_backup,
btrfs_header_level(info->fs_root->node));
}
btrfs_set_backup_dev_root(root_backup, info->dev_root->node->start);
btrfs_set_backup_dev_root_gen(root_backup,
btrfs_header_generation(info->dev_root->node));
btrfs_set_backup_dev_root_level(root_backup,
btrfs_header_level(info->dev_root->node));
btrfs_set_backup_csum_root(root_backup, info->csum_root->node->start);
btrfs_set_backup_csum_root_gen(root_backup,
btrfs_header_generation(info->csum_root->node));
btrfs_set_backup_csum_root_level(root_backup,
btrfs_header_level(info->csum_root->node));
btrfs_set_backup_total_bytes(root_backup,
btrfs_super_total_bytes(info->super_copy));
btrfs_set_backup_bytes_used(root_backup,
btrfs_super_bytes_used(info->super_copy));
btrfs_set_backup_num_devices(root_backup,
btrfs_super_num_devices(info->super_copy));
/*
* if we don't copy this out to the super_copy, it won't get remembered
* for the next commit
*/
memcpy(&info->super_copy->super_roots,
&info->super_for_commit->super_roots,
sizeof(*root_backup) * BTRFS_NUM_BACKUP_ROOTS);
}
/*
* this copies info out of the root backup array and back into
* the in-memory super block. It is meant to help iterate through
* the array, so you send it the number of backups you've already
* tried and the last backup index you used.
*
* this returns -1 when it has tried all the backups
*/
static noinline int next_root_backup(struct btrfs_fs_info *info,
struct btrfs_super_block *super,
int *num_backups_tried, int *backup_index)
{
struct btrfs_root_backup *root_backup;
int newest = *backup_index;
if (*num_backups_tried == 0) {
u64 gen = btrfs_super_generation(super);
newest = find_newest_super_backup(info, gen);
if (newest == -1)
return -1;
*backup_index = newest; *num_backups_tried = 1;
} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {
/* we've tried all the backups, all done */
return -1;
} else {
/* jump to the next oldest backup */
newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %
BTRFS_NUM_BACKUP_ROOTS;
*backup_index = newest;
*num_backups_tried += 1;
}
root_backup = super->super_roots + newest;
btrfs_set_super_generation(super,
btrfs_backup_tree_root_gen(root_backup));
btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));
btrfs_set_super_root_level(super,
btrfs_backup_tree_root_level(root_backup));
btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));
/*
* fixme: the total bytes and num_devices need to match or we should
* need a fsck
*/
btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));
btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));
return 0;
}
/* helper to cleanup tree roots */
static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root)
{
free_extent_buffer(info->tree_root->node);
free_extent_buffer(info->tree_root->commit_root);
free_extent_buffer(info->dev_root->node);
free_extent_buffer(info->dev_root->commit_root);
free_extent_buffer(info->extent_root->node);
free_extent_buffer(info->extent_root->commit_root);
free_extent_buffer(info->csum_root->node);
free_extent_buffer(info->csum_root->commit_root);
info->tree_root->node = NULL;
info->tree_root->commit_root = NULL;
info->dev_root->node = NULL;
info->dev_root->commit_root = NULL;
info->extent_root->node = NULL;
info->extent_root->commit_root = NULL;
info->csum_root->node = NULL;
info->csum_root->commit_root = NULL;
if (chunk_root) {
free_extent_buffer(info->chunk_root->node);
free_extent_buffer(info->chunk_root->commit_root);
info->chunk_root->node = NULL;
info->chunk_root->commit_root = NULL;
}
}
struct btrfs_root *open_ctree(struct super_block *sb,
struct btrfs_fs_devices *fs_devices,
char *options)
{
u32 sectorsize;
u32 nodesize;
u32 leafsize;
u32 blocksize;
u32 stripesize;
u64 generation;
u64 features; struct btrfs_key location;
struct buffer_head *bh;
struct btrfs_super_block *disk_super;
struct btrfs_root *tree_root = btrfs_sb(sb);
struct btrfs_fs_info *fs_info = tree_root->fs_info;
struct btrfs_root *extent_root;
struct btrfs_root *csum_root;
struct btrfs_root *chunk_root;
struct btrfs_root *dev_root;
struct btrfs_root *log_tree_root;
int ret;
int err = -EINVAL;
int num_backups_tried = 0;
int backup_index = 0;
extent_root = fs_info->extent_root =
kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
csum_root = fs_info->csum_root =
kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
chunk_root = fs_info->chunk_root =
kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
dev_root = fs_info->dev_root =
kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
if (!extent_root || !csum_root || !chunk_root || !dev_root) {
err = -ENOMEM;
goto fail;
}
ret = init_srcu_struct(&fs_info->subvol_srcu);
if (ret) {
err = ret;
goto fail;
}
ret = setup_bdi(fs_info, &fs_info->bdi);
if (ret) {
err = ret;
goto fail_srcu;
}
fs_info->btree_inode = new_inode(sb);
if (!fs_info->btree_inode) {
err = -ENOMEM;
goto fail_bdi;
}
mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
INIT_LIST_HEAD(&fs_info->trans_list);
INIT_LIST_HEAD(&fs_info->dead_roots);
INIT_LIST_HEAD(&fs_info->delayed_iputs);
INIT_LIST_HEAD(&fs_info->hashers);
INIT_LIST_HEAD(&fs_info->delalloc_inodes);
INIT_LIST_HEAD(&fs_info->ordered_operations);
INIT_LIST_HEAD(&fs_info->caching_block_groups);
spin_lock_init(&fs_info->delalloc_lock);
spin_lock_init(&fs_info->trans_lock);
spin_lock_init(&fs_info->ref_cache_lock);
spin_lock_init(&fs_info->fs_roots_radix_lock);
spin_lock_init(&fs_info->delayed_iput_lock);
spin_lock_init(&fs_info->defrag_inodes_lock);
spin_lock_init(&fs_info->free_chunk_lock);
mutex_init(&fs_info->reloc_mutex);
init_completion(&fs_info->kobj_unregister);
INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
INIT_LIST_HEAD(&fs_info->space_info);
btrfs_mapping_init(&fs_info->mapping_tree); btrfs_init_block_rsv(&fs_info->global_block_rsv);
btrfs_init_block_rsv(&fs_info->delalloc_block_rsv);
btrfs_init_block_rsv(&fs_info->trans_block_rsv);
btrfs_init_block_rsv(&fs_info->chunk_block_rsv);
btrfs_init_block_rsv(&fs_info->empty_block_rsv);
btrfs_init_block_rsv(&fs_info->delayed_block_rsv);
atomic_set(&fs_info->nr_async_submits, 0);
atomic_set(&fs_info->async_delalloc_pages, 0);
atomic_set(&fs_info->async_submit_draining, 0);
atomic_set(&fs_info->nr_async_bios, 0);
atomic_set(&fs_info->defrag_running, 0);
fs_info->sb = sb;
fs_info->max_inline = 8192 * 1024;
fs_info->metadata_ratio = 0;
fs_info->defrag_inodes = RB_ROOT;
fs_info->trans_no_join = 0;
fs_info->free_chunk_space = 0;
/* readahead state */
INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
spin_lock_init(&fs_info->reada_lock);
fs_info->thread_pool_size = min_t(unsigned long,
num_online_cpus() + 2, 8);
INIT_LIST_HEAD(&fs_info->ordered_extents);
spin_lock_init(&fs_info->ordered_extent_lock);
fs_info->delayed_root = kmalloc(sizeof(struct btrfs_delayed_root),
GFP_NOFS);
if (!fs_info->delayed_root) {
err = -ENOMEM;
goto fail_iput;
}
btrfs_init_delayed_root(fs_info->delayed_root);
mutex_init(&fs_info->scrub_lock);
atomic_set(&fs_info->scrubs_running, 0);
atomic_set(&fs_info->scrub_pause_req, 0);
atomic_set(&fs_info->scrubs_paused, 0);
atomic_set(&fs_info->scrub_cancel_req, 0);
init_waitqueue_head(&fs_info->scrub_pause_wait);
init_rwsem(&fs_info->scrub_super_lock);
fs_info->scrub_workers_refcnt = 0;
sb->s_blocksize = 4096;
sb->s_blocksize_bits = blksize_bits(4096);
sb->s_bdi = &fs_info->bdi;
fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
fs_info->btree_inode->i_nlink = 1;
/*
* we set the i_size on the btree inode to the max possible int.
* the real end of the address space is determined by all of
* the devices in the system
*/
fs_info->btree_inode->i_size = OFFSET_MAX;
fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
fs_info->btree_inode->i_mapping->backing_dev_info = &fs_info->bdi;
RB_CLEAR_NODE(&BTRFS_I(fs_info->btree_inode)->rb_node);
extent_io_tree_init(&BTRFS_I(fs_info->btree_inode)->io_tree,
fs_info->btree_inode->i_mapping);
extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree);
BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
BTRFS_I(fs_info->btree_inode)->root = tree_root;
memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
sizeof(struct btrfs_key));
BTRFS_I(fs_info->btree_inode)->dummy_inode = 1; insert_inode_hash(fs_info->btree_inode);
spin_lock_init(&fs_info->block_group_cache_lock);
fs_info->block_group_cache_tree = RB_ROOT;
extent_io_tree_init(&fs_info->freed_extents[0],
fs_info->btree_inode->i_mapping);
extent_io_tree_init(&fs_info->freed_extents[1],
fs_info->btree_inode->i_mapping);
fs_info->pinned_extents = &fs_info->freed_extents[0];
fs_info->do_barriers = 1;
mutex_init(&fs_info->ordered_operations_mutex);
mutex_init(&fs_info->tree_log_mutex);
mutex_init(&fs_info->chunk_mutex);
mutex_init(&fs_info->transaction_kthread_mutex);
mutex_init(&fs_info->cleaner_mutex);
mutex_init(&fs_info->volume_mutex);
init_rwsem(&fs_info->extent_commit_sem);
init_rwsem(&fs_info->cleanup_work_sem);
init_rwsem(&fs_info->subvol_sem);
btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
init_waitqueue_head(&fs_info->transaction_throttle);
init_waitqueue_head(&fs_info->transaction_wait);
init_waitqueue_head(&fs_info->transaction_blocked_wait);
init_waitqueue_head(&fs_info->async_submit_wait);
__setup_root(4096, 4096, 4096, 4096, tree_root,
fs_info, BTRFS_ROOT_TREE_OBJECTID);
bh = btrfs_read_dev_super(fs_devices->latest_bdev);
if (!bh) {
err = -EINVAL;
goto fail_alloc;
}
memcpy(fs_info->super_copy, bh->b_data, sizeof(*fs_info->super_copy));
memcpy(fs_info->super_for_commit, fs_info->super_copy,
sizeof(*fs_info->super_for_commit));
brelse(bh);
memcpy(fs_info->fsid, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
disk_super = fs_info->super_copy;
if (!btrfs_super_root(disk_super))
goto fail_alloc;
/* check FS state, whether FS is broken. */
fs_info->fs_state |= btrfs_super_flags(disk_super);
btrfs_check_super_valid(fs_info, sb->s_flags & MS_RDONLY);
/*
* run through our array of backup supers and setup
* our ring pointer to the oldest one
*/
generation = btrfs_super_generation(disk_super);
find_oldest_super_backup(fs_info, generation);
/*
* In the long term, we'll store the compression type in the super
* block, and it'll be used for per file compression control.
*/
fs_info->compress_type = BTRFS_COMPRESS_ZLIB;
ret = btrfs_parse_options(tree_root, options); if (ret) {
err = ret;
goto fail_alloc;
}
features = btrfs_super_incompat_flags(disk_super) &
~BTRFS_FEATURE_INCOMPAT_SUPP;
if (features) {
printk(KERN_ERR "BTRFS: couldn't mount because of "
"unsupported optional features (%Lx).\n",
(unsigned long long)features);
err = -EINVAL;
goto fail_alloc;
}
features = btrfs_super_incompat_flags(disk_super);
features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
btrfs_set_super_incompat_flags(disk_super, features);
features = btrfs_super_compat_ro_flags(disk_super) &
~BTRFS_FEATURE_COMPAT_RO_SUPP;
if (!(sb->s_flags & MS_RDONLY) && features) {
printk(KERN_ERR "BTRFS: couldn't mount RDWR because of "
"unsupported option features (%Lx).\n",
(unsigned long long)features);
err = -EINVAL;
goto fail_alloc;
}
btrfs_init_workers(&fs_info->generic_worker,
"genwork", 1, NULL);
btrfs_init_workers(&fs_info->workers, "worker",
fs_info->thread_pool_size,
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
fs_info->thread_pool_size,
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->submit_workers, "submit",
min_t(u64, fs_devices->num_devices,
fs_info->thread_pool_size),
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->caching_workers, "cache",
2, &fs_info->generic_worker);
/* a higher idle thresh on the submit workers makes it much more
* likely that bios will be send down in a sane order to the
* devices
*/
fs_info->submit_workers.idle_thresh = 64;
fs_info->workers.idle_thresh = 16;
fs_info->workers.ordered = 1;
fs_info->delalloc_workers.idle_thresh = 2;
fs_info->delalloc_workers.ordered = 1;
btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->endio_workers, "endio",
fs_info->thread_pool_size,
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
fs_info->thread_pool_size,
&fs_info->generic_worker); btrfs_init_workers(&fs_info->endio_meta_write_workers,
"endio-meta-write", fs_info->thread_pool_size,
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
fs_info->thread_pool_size,
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->endio_freespace_worker, "freespace-write",
1, &fs_info->generic_worker);
btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
fs_info->thread_pool_size,
&fs_info->generic_worker);
btrfs_init_workers(&fs_info->readahead_workers, "readahead",
fs_info->thread_pool_size,
&fs_info->generic_worker);
/*
* endios are largely parallel and should have a very
* low idle thresh
*/
fs_info->endio_workers.idle_thresh = 4;
fs_info->endio_meta_workers.idle_thresh = 4;
fs_info->endio_write_workers.idle_thresh = 2;
fs_info->endio_meta_write_workers.idle_thresh = 2;
fs_info->readahead_workers.idle_thresh = 2;
/*
* btrfs_start_workers can really only fail because of ENOMEM so just
* return -ENOMEM if any of these fail.
*/
ret = btrfs_start_workers(&fs_info->workers);
ret |= btrfs_start_workers(&fs_info->generic_worker);
ret |= btrfs_start_workers(&fs_info->submit_workers);
ret |= btrfs_start_workers(&fs_info->delalloc_workers);
ret |= btrfs_start_workers(&fs_info->fixup_workers);
ret |= btrfs_start_workers(&fs_info->endio_workers);
ret |= btrfs_start_workers(&fs_info->endio_meta_workers);
ret |= btrfs_start_workers(&fs_info->endio_meta_write_workers);
ret |= btrfs_start_workers(&fs_info->endio_write_workers);
ret |= btrfs_start_workers(&fs_info->endio_freespace_worker);
ret |= btrfs_start_workers(&fs_info->delayed_workers);
ret |= btrfs_start_workers(&fs_info->caching_workers);
ret |= btrfs_start_workers(&fs_info->readahead_workers);
if (ret) {
ret = -ENOMEM;
goto fail_sb_buffer;
}
fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
4 * 1024 * 1024 / PAGE_CACHE_SIZE);
nodesize = btrfs_super_nodesize(disk_super);
leafsize = btrfs_super_leafsize(disk_super);
sectorsize = btrfs_super_sectorsize(disk_super);
stripesize = btrfs_super_stripesize(disk_super);
tree_root->nodesize = nodesize;
tree_root->leafsize = leafsize;
tree_root->sectorsize = sectorsize;
tree_root->stripesize = stripesize;
sb->s_blocksize = sectorsize;
sb->s_blocksize_bits = blksize_bits(sectorsize);
if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
sizeof(disk_super->magic))) {
printk(KERN_INFO "btrfs: valid FS not found on %s\n", sb->s_id);
goto fail_sb_buffer;
}
mutex_lock(&fs_info->chunk_mutex);
ret = btrfs_read_sys_array(tree_root);
mutex_unlock(&fs_info->chunk_mutex);
if (ret) {
printk(KERN_WARNING "btrfs: failed to read the system "
"array on %s\n", sb->s_id);
goto fail_sb_buffer;
}
blocksize = btrfs_level_size(tree_root,
btrfs_super_chunk_root_level(disk_super));
generation = btrfs_super_chunk_root_generation(disk_super);
__setup_root(nodesize, leafsize, sectorsize, stripesize,
chunk_root, fs_info, BTRFS_CHUNK_TREE_OBJECTID);
chunk_root->node = read_tree_block(chunk_root,
btrfs_super_chunk_root(disk_super),
blocksize, generation);
BUG_ON(!chunk_root->node);
if (!test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) {
printk(KERN_WARNING "btrfs: failed to read chunk root on %s\n",
sb->s_id);
goto fail_tree_roots;
}
btrfs_set_root_node(&chunk_root->root_item, chunk_root->node);
chunk_root->commit_root = btrfs_root_node(chunk_root);
read_extent_buffer(chunk_root->node, fs_info->chunk_tree_uuid,
(unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
BTRFS_UUID_SIZE);
mutex_lock(&fs_info->chunk_mutex);
ret = btrfs_read_chunk_tree(chunk_root);
mutex_unlock(&fs_info->chunk_mutex);
if (ret) {
printk(KERN_WARNING "btrfs: failed to read chunk tree on %s\n",
sb->s_id);
goto fail_tree_roots;
}
btrfs_close_extra_devices(fs_devices);
retry_root_backup:
blocksize = btrfs_level_size(tree_root,
btrfs_super_root_level(disk_super));
generation = btrfs_super_generation(disk_super);
tree_root->node = read_tree_block(tree_root,
btrfs_super_root(disk_super),
blocksize, generation);
if (!tree_root->node ||
!test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) {
printk(KERN_WARNING "btrfs: failed to read tree root on %s\n",
sb->s_id);
goto recovery_tree_root;
}
btrfs_set_root_node(&tree_root->root_item, tree_root->node);
tree_root->commit_root = btrfs_root_node(tree_root);
ret = find_and_setup_root(tree_root, fs_info,
BTRFS_EXTENT_TREE_OBJECTID, extent_root);
if (ret)
goto recovery_tree_root;
extent_root->track_dirty = 1;
ret = find_and_setup_root(tree_root, fs_info,
BTRFS_DEV_TREE_OBJECTID, dev_root); if (ret)
goto recovery_tree_root;
dev_root->track_dirty = 1;
ret = find_and_setup_root(tree_root, fs_info,
BTRFS_CSUM_TREE_OBJECTID, csum_root);
if (ret)
goto recovery_tree_root;
csum_root->track_dirty = 1;
fs_info->generation = generation;
fs_info->last_trans_committed = generation;
fs_info->data_alloc_profile = (u64)-1;
fs_info->metadata_alloc_profile = (u64)-1;
fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
ret = btrfs_init_space_info(fs_info);
if (ret) {
printk(KERN_ERR "Failed to initial space info: %d\n", ret);
goto fail_block_groups;
}
ret = btrfs_read_block_groups(extent_root);
if (ret) {
printk(KERN_ERR "Failed to read block groups: %d\n", ret);
goto fail_block_groups;
}
fs_info->cleaner_kthread = kthread_run(cleaner_kthread, tree_root,
"btrfs-cleaner");
if (IS_ERR(fs_info->cleaner_kthread))
goto fail_block_groups;
fs_info->transaction_kthread = kthread_run(transaction_kthread,
tree_root,
"btrfs-transaction");
if (IS_ERR(fs_info->transaction_kthread))
goto fail_cleaner;
if (!btrfs_test_opt(tree_root, SSD) &&
!btrfs_test_opt(tree_root, NOSSD) &&
!fs_info->fs_devices->rotating) {
printk(KERN_INFO "Btrfs detected SSD devices, enabling SSD "
"mode\n");
btrfs_set_opt(fs_info->mount_opt, SSD);
}
/* do not make disk changes in broken FS */
if (btrfs_super_log_root(disk_super) != 0 &&
!(fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)) {
u64 bytenr = btrfs_super_log_root(disk_super);
if (fs_devices->rw_devices == 0) {
printk(KERN_WARNING "Btrfs log replay required "
"on RO media\n");
err = -EIO;
goto fail_trans_kthread;
}
blocksize =
btrfs_level_size(tree_root,
btrfs_super_log_root_level(disk_super));
log_tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS);
if (!log_tree_root) {
err = -ENOMEM;
goto fail_trans_kthread;
}
__setup_root(nodesize, leafsize, sectorsize, stripesize, log_tree_root, fs_info, BTRFS_TREE_LOG_OBJECTID);
log_tree_root->node = read_tree_block(tree_root, bytenr,
blocksize,
generation + 1);
ret = btrfs_recover_log_trees(log_tree_root);
BUG_ON(ret);
if (sb->s_flags & MS_RDONLY) {
ret = btrfs_commit_super(tree_root);
BUG_ON(ret);
}
}
ret = btrfs_find_orphan_roots(tree_root);
BUG_ON(ret);
if (!(sb->s_flags & MS_RDONLY)) {
ret = btrfs_cleanup_fs_roots(fs_info);
BUG_ON(ret);
ret = btrfs_recover_relocation(tree_root);
if (ret < 0) {
printk(KERN_WARNING
"btrfs: failed to recover relocation\n");
err = -EINVAL;
goto fail_trans_kthread;
}
}
location.objectid = BTRFS_FS_TREE_OBJECTID;
location.type = BTRFS_ROOT_ITEM_KEY;
location.offset = (u64)-1;
fs_info->fs_root = btrfs_read_fs_root_no_name(fs_info, &location);
if (!fs_info->fs_root)
goto fail_trans_kthread;
if (IS_ERR(fs_info->fs_root)) {
err = PTR_ERR(fs_info->fs_root);
goto fail_trans_kthread;
}
if (!(sb->s_flags & MS_RDONLY)) {
down_read(&fs_info->cleanup_work_sem);
err = btrfs_orphan_cleanup(fs_info->fs_root);
if (!err)
err = btrfs_orphan_cleanup(fs_info->tree_root);
up_read(&fs_info->cleanup_work_sem);
if (err) {
close_ctree(tree_root);
return ERR_PTR(err);
}
}
return tree_root;
fail_trans_kthread:
kthread_stop(fs_info->transaction_kthread);
fail_cleaner:
kthread_stop(fs_info->cleaner_kthread);
/*
* make sure we're done with the btree inode before we stop our
* kthreads
*/
filemap_write_and_wait(fs_info->btree_inode->i_mapping);
invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
fail_block_groups:
btrfs_free_block_groups(fs_info);
fail_tree_roots:
free_root_pointers(fs_info, 1);
fail_sb_buffer:
btrfs_stop_workers(&fs_info->generic_worker);
btrfs_stop_workers(&fs_info->readahead_workers);
btrfs_stop_workers(&fs_info->fixup_workers);
btrfs_stop_workers(&fs_info->delalloc_workers);
btrfs_stop_workers(&fs_info->workers);
btrfs_stop_workers(&fs_info->endio_workers);
btrfs_stop_workers(&fs_info->endio_meta_workers);
btrfs_stop_workers(&fs_info->endio_meta_write_workers);
btrfs_stop_workers(&fs_info->endio_write_workers);
btrfs_stop_workers(&fs_info->endio_freespace_worker);
btrfs_stop_workers(&fs_info->submit_workers);
btrfs_stop_workers(&fs_info->delayed_workers);
btrfs_stop_workers(&fs_info->caching_workers);
fail_alloc:
fail_iput:
btrfs_mapping_tree_free(&fs_info->mapping_tree);
invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
iput(fs_info->btree_inode);
fail_bdi:
bdi_destroy(&fs_info->bdi);
fail_srcu:
cleanup_srcu_struct(&fs_info->subvol_srcu);
fail:
btrfs_close_devices(fs_info->fs_devices);
free_fs_info(fs_info);
return ERR_PTR(err);
recovery_tree_root:
if (!btrfs_test_opt(tree_root, RECOVERY))
goto fail_tree_roots;
free_root_pointers(fs_info, 0);
/* don't use the log in recovery mode, it won't be valid */
btrfs_set_super_log_root(disk_super, 0);
/* we can't trust the free space cache either */
btrfs_set_opt(fs_info->mount_opt, CLEAR_CACHE);
ret = next_root_backup(fs_info, fs_info->super_copy,
&num_backups_tried, &backup_index);
if (ret == -1)
goto fail_block_groups;
goto retry_root_backup;
}
static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
{
char b[BDEVNAME_SIZE];
if (uptodate) {
set_buffer_uptodate(bh);
} else {
printk_ratelimited(KERN_WARNING "lost page write due to "
"I/O error on %s\n",
bdevname(bh->b_bdev, b));
/* note, we dont' set_buffer_write_io_error because we have
* our own ways of dealing with the IO errors
*/
clear_buffer_uptodate(bh);
}
unlock_buffer(bh);
put_bh(bh);
}
struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
{
struct buffer_head *bh;
struct buffer_head *latest = NULL;
struct btrfs_super_block *super;
int i;
u64 transid = 0;
u64 bytenr;
/* we would like to check all the supers, but that would make
* a btrfs mount succeed after a mkfs from a different FS.
* So, we need to add a special mount option to scan for
* later supers, using BTRFS_SUPER_MIRROR_MAX instead
*/
for (i = 0; i < 1; i++) {
bytenr = btrfs_sb_offset(i);
if (bytenr + 4096 >= i_size_read(bdev->bd_inode))
break;
bh = __bread(bdev, bytenr / 4096, 4096);
if (!bh)
continue;
super = (struct btrfs_super_block *)bh->b_data;
if (btrfs_super_bytenr(super) != bytenr ||
strncmp((char *)(&super->magic), BTRFS_MAGIC,
sizeof(super->magic))) {
brelse(bh);
continue;
}
if (!latest || btrfs_super_generation(super) > transid) {
brelse(latest);
latest = bh;
transid = btrfs_super_generation(super);
} else {
brelse(bh);
}
}
return latest;
}
/*
* this should be called twice, once with wait == 0 and
* once with wait == 1. When wait == 0 is done, all the buffer heads
* we write are pinned.
*
* They are released when wait == 1 is done.
* max_mirrors must be the same for both runs, and it indicates how
* many supers on this one device should be written.
*
* max_mirrors == 0 means to write them all.
*/
static int write_dev_supers(struct btrfs_device *device,
struct btrfs_super_block *sb,
int do_barriers, int wait, int max_mirrors)
{
struct buffer_head *bh;
int i;
int ret;
int errors = 0;
u32 crc;
u64 bytenr;
if (max_mirrors == 0)
max_mirrors = BTRFS_SUPER_MIRROR_MAX;
for (i = 0; i < max_mirrors; i++) {
bytenr = btrfs_sb_offset(i);
if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes) break;
if (wait) {
bh = __find_get_block(device->bdev, bytenr / 4096,
BTRFS_SUPER_INFO_SIZE);
BUG_ON(!bh);
wait_on_buffer(bh);
if (!buffer_uptodate(bh))
errors++;
/* drop our reference */
brelse(bh);
/* drop the reference from the wait == 0 run */
brelse(bh);
continue;
} else {
btrfs_set_super_bytenr(sb, bytenr);
crc = ~(u32)0;
crc = btrfs_csum_data(NULL, (char *)sb +
BTRFS_CSUM_SIZE, crc,
BTRFS_SUPER_INFO_SIZE -
BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, sb->csum);
/*
* one reference for us, and we leave it for the
* caller
*/
bh = __getblk(device->bdev, bytenr / 4096,
BTRFS_SUPER_INFO_SIZE);
memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
/* one reference for submit_bh */
get_bh(bh);
set_buffer_uptodate(bh);
lock_buffer(bh);
bh->b_end_io = btrfs_end_buffer_write_sync;
}
/*
* we fua the first super. The others we allow
* to go down lazy.
*/
ret = submit_bh(WRITE_FUA, bh);
if (ret)
errors++;
}
return errors < i ? 0 : -1;
}
/*
* endio for the write_dev_flush, this will wake anyone waiting
* for the barrier when it is done
*/
static void btrfs_end_empty_barrier(struct bio *bio, int err)
{
if (err) {
if (err == -EOPNOTSUPP)
set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
clear_bit(BIO_UPTODATE, &bio->bi_flags);
}
if (bio->bi_private)
complete(bio->bi_private);
bio_put(bio);
}
/* * trigger flushes for one the devices. If you pass wait == 0, the flushes are
* sent down. With wait == 1, it waits for the previous flush.
*
* any device where the flush fails with eopnotsupp are flagged as not-barrier
* capable
*/
static int write_dev_flush(struct btrfs_device *device, int wait)
{
struct bio *bio;
int ret = 0;
if (device->nobarriers)
return 0;
if (wait) {
bio = device->flush_bio;
if (!bio)
return 0;
wait_for_completion(&device->flush_wait);
if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
printk("btrfs: disabling barriers on dev %s\n",
device->name);
device->nobarriers = 1;
}
if (!bio_flagged(bio, BIO_UPTODATE)) {
ret = -EIO;
}
/* drop the reference from the wait == 0 run */
bio_put(bio);
device->flush_bio = NULL;
return ret;
}
/*
* one reference for us, and we leave it for the
* caller
*/
device->flush_bio = NULL;;
bio = bio_alloc(GFP_NOFS, 0);
if (!bio)
return -ENOMEM;
bio->bi_end_io = btrfs_end_empty_barrier;
bio->bi_bdev = device->bdev;
init_completion(&device->flush_wait);
bio->bi_private = &device->flush_wait;
device->flush_bio = bio;
bio_get(bio);
submit_bio(WRITE_FLUSH, bio);
return 0;
}
/*
* send an empty flush down to each device in parallel,
* then wait for them
*/
static int barrier_all_devices(struct btrfs_fs_info *info)
{
struct list_head *head;
struct btrfs_device *dev;
int errors = 0;
int ret;
/* send down all the barriers */ head = &info->fs_devices->devices;
list_for_each_entry_rcu(dev, head, dev_list) {
if (!dev->bdev) {
errors++;
continue;
}
if (!dev->in_fs_metadata || !dev->writeable)
continue;
ret = write_dev_flush(dev, 0);
if (ret)
errors++;
}
/* wait for all the barriers */
list_for_each_entry_rcu(dev, head, dev_list) {
if (!dev->bdev) {
errors++;
continue;
}
if (!dev->in_fs_metadata || !dev->writeable)
continue;
ret = write_dev_flush(dev, 1);
if (ret)
errors++;
}
if (errors)
return -EIO;
return 0;
}
int write_all_supers(struct btrfs_root *root, int max_mirrors)
{
struct list_head *head;
struct btrfs_device *dev;
struct btrfs_super_block *sb;
struct btrfs_dev_item *dev_item;
int ret;
int do_barriers;
int max_errors;
int total_errors = 0;
u64 flags;
max_errors = btrfs_super_num_devices(root->fs_info->super_copy) - 1;
do_barriers = !btrfs_test_opt(root, NOBARRIER);
backup_super_roots(root->fs_info);
sb = root->fs_info->super_for_commit;
dev_item = &sb->dev_item;
mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
head = &root->fs_info->fs_devices->devices;
if (do_barriers)
barrier_all_devices(root->fs_info);
list_for_each_entry_rcu(dev, head, dev_list) {
if (!dev->bdev) {
total_errors++;
continue;
}
if (!dev->in_fs_metadata || !dev->writeable)
continue;
btrfs_set_stack_device_generation(dev_item, 0);
btrfs_set_stack_device_type(dev_item, dev->type);
btrfs_set_stack_device_id(dev_item, dev->devid);
btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes);
btrfs_set_stack_device_bytes_used(dev_item, dev->bytes_used); btrfs_set_stack_device_io_align(dev_item, dev->io_align);
btrfs_set_stack_device_io_width(dev_item, dev->io_width);
btrfs_set_stack_device_sector_size(dev_item, dev->sector_size);
memcpy(dev_item->uuid, dev->uuid, BTRFS_UUID_SIZE);
memcpy(dev_item->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);
flags = btrfs_super_flags(sb);
btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
ret = write_dev_supers(dev, sb, do_barriers, 0, max_mirrors);
if (ret)
total_errors++;
}
if (total_errors > max_errors) {
printk(KERN_ERR "btrfs: %d errors while writing supers\n",
total_errors);
BUG();
}
total_errors = 0;
list_for_each_entry_rcu(dev, head, dev_list) {
if (!dev->bdev)
continue;
if (!dev->in_fs_metadata || !dev->writeable)
continue;
ret = write_dev_supers(dev, sb, do_barriers, 1, max_mirrors);
if (ret)
total_errors++;
}
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
if (total_errors > max_errors) {
printk(KERN_ERR "btrfs: %d errors while writing supers\n",
total_errors);
BUG();
}
return 0;
}
int write_ctree_super(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int max_mirrors)
{
int ret;
ret = write_all_supers(root, max_mirrors);
return ret;
}
int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
{
spin_lock(&fs_info->fs_roots_radix_lock);
radix_tree_delete(&fs_info->fs_roots_radix,
(unsigned long)root->root_key.objectid);
spin_unlock(&fs_info->fs_roots_radix_lock);
if (btrfs_root_refs(&root->root_item) == 0)
synchronize_srcu(&fs_info->subvol_srcu);
__btrfs_remove_free_space_cache(root->free_ino_pinned);
__btrfs_remove_free_space_cache(root->free_ino_ctl);
free_fs_root(root);
return 0;
}
static void free_fs_root(struct btrfs_root *root)
{
iput(root->cache_inode);
WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
if (root->anon_dev)
free_anon_bdev(root->anon_dev); free_extent_buffer(root->node);
free_extent_buffer(root->commit_root);
kfree(root->free_ino_ctl);
kfree(root->free_ino_pinned);
kfree(root->name);
kfree(root);
}
static int del_fs_roots(struct btrfs_fs_info *fs_info)
{
int ret;
struct btrfs_root *gang[8];
int i;
while (!list_empty(&fs_info->dead_roots)) {
gang[0] = list_entry(fs_info->dead_roots.next,
struct btrfs_root, root_list);
list_del(&gang[0]->root_list);
if (gang[0]->in_radix) {
btrfs_free_fs_root(fs_info, gang[0]);
} else {
free_extent_buffer(gang[0]->node);
free_extent_buffer(gang[0]->commit_root);
kfree(gang[0]);
}
}
while (1) {
ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
(void **)gang, 0,
ARRAY_SIZE(gang));
if (!ret)
break;
for (i = 0; i < ret; i++)
btrfs_free_fs_root(fs_info, gang[i]);
}
return 0;
}
int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
{
u64 root_objectid = 0;
struct btrfs_root *gang[8];
int i;
int ret;
while (1) {
ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
(void **)gang, root_objectid,
ARRAY_SIZE(gang));
if (!ret)
break;
root_objectid = gang[ret - 1]->root_key.objectid + 1;
for (i = 0; i < ret; i++) {
int err;
root_objectid = gang[i]->root_key.objectid;
err = btrfs_orphan_cleanup(gang[i]);
if (err)
return err;
}
root_objectid++;
}
return 0;
}
int btrfs_commit_super(struct btrfs_root *root)
{ struct btrfs_trans_handle *trans;
int ret;
mutex_lock(&root->fs_info->cleaner_mutex);
btrfs_run_delayed_iputs(root);
btrfs_clean_old_snapshots(root);
mutex_unlock(&root->fs_info->cleaner_mutex);
/* wait until ongoing cleanup work done */
down_write(&root->fs_info->cleanup_work_sem);
up_write(&root->fs_info->cleanup_work_sem);
trans = btrfs_join_transaction(root);
if (IS_ERR(trans))
return PTR_ERR(trans);
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
/* run commit again to drop the original snapshot */
trans = btrfs_join_transaction(root);
if (IS_ERR(trans))
return PTR_ERR(trans);
btrfs_commit_transaction(trans, root);
ret = btrfs_write_and_wait_transaction(NULL, root);
BUG_ON(ret);
ret = write_ctree_super(NULL, root, 0);
return ret;
}
int close_ctree(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
int ret;
fs_info->closing = 1;
smp_mb();
btrfs_scrub_cancel(root);
/* wait for any defraggers to finish */
wait_event(fs_info->transaction_wait,
(atomic_read(&fs_info->defrag_running) == 0));
/* clear out the rbtree of defraggable inodes */
btrfs_run_defrag_inodes(root->fs_info);
/*
* Here come 2 situations when btrfs is broken to flip readonly:
*
* 1. when btrfs flips readonly somewhere else before
* btrfs_commit_super, sb->s_flags has MS_RDONLY flag,
* and btrfs will skip to write sb directly to keep
* ERROR state on disk.
*
* 2. when btrfs flips readonly just in btrfs_commit_super,
* and in such case, btrfs cannot write sb via btrfs_commit_super,
* and since fs_state has been set BTRFS_SUPER_FLAG_ERROR flag,
* btrfs will cleanup all FS resources first and write sb then.
*/
if (!(fs_info->sb->s_flags & MS_RDONLY)) {
ret = btrfs_commit_super(root);
if (ret)
printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
}
if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
ret = btrfs_error_commit_super(root);
if (ret)
printk(KERN_ERR "btrfs: commit super ret %d\n", ret);
}
btrfs_put_block_group_cache(fs_info);
kthread_stop(root->fs_info->transaction_kthread);
kthread_stop(root->fs_info->cleaner_kthread);
fs_info->closing = 2;
smp_mb();
if (fs_info->delalloc_bytes) {
printk(KERN_INFO "btrfs: at unmount delalloc count %llu\n",
(unsigned long long)fs_info->delalloc_bytes);
}
if (fs_info->total_ref_cache_size) {
printk(KERN_INFO "btrfs: at umount reference cache size %llu\n",
(unsigned long long)fs_info->total_ref_cache_size);
}
free_extent_buffer(fs_info->extent_root->node);
free_extent_buffer(fs_info->extent_root->commit_root);
free_extent_buffer(fs_info->tree_root->node);
free_extent_buffer(fs_info->tree_root->commit_root);
free_extent_buffer(root->fs_info->chunk_root->node);
free_extent_buffer(root->fs_info->chunk_root->commit_root);
free_extent_buffer(root->fs_info->dev_root->node);
free_extent_buffer(root->fs_info->dev_root->commit_root);
free_extent_buffer(root->fs_info->csum_root->node);
free_extent_buffer(root->fs_info->csum_root->commit_root);
btrfs_free_block_groups(root->fs_info);
del_fs_roots(fs_info);
iput(fs_info->btree_inode);
btrfs_stop_workers(&fs_info->generic_worker);
btrfs_stop_workers(&fs_info->fixup_workers);
btrfs_stop_workers(&fs_info->delalloc_workers);
btrfs_stop_workers(&fs_info->workers);
btrfs_stop_workers(&fs_info->endio_workers);
btrfs_stop_workers(&fs_info->endio_meta_workers);
btrfs_stop_workers(&fs_info->endio_meta_write_workers);
btrfs_stop_workers(&fs_info->endio_write_workers);
btrfs_stop_workers(&fs_info->endio_freespace_worker);
btrfs_stop_workers(&fs_info->submit_workers);
btrfs_stop_workers(&fs_info->delayed_workers);
btrfs_stop_workers(&fs_info->caching_workers);
btrfs_stop_workers(&fs_info->readahead_workers);
btrfs_close_devices(fs_info->fs_devices);
btrfs_mapping_tree_free(&fs_info->mapping_tree);
bdi_destroy(&fs_info->bdi);
cleanup_srcu_struct(&fs_info->subvol_srcu);
free_fs_info(fs_info);
return 0;
}
int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
{
int ret;
struct inode *btree_inode = buf->first_page->mapping->host;
ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
NULL);
if (!ret)
return ret;
ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
parent_transid);
return !ret;
}
int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
{
struct inode *btree_inode = buf->first_page->mapping->host;
return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree,
buf);
}
void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
{
struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
u64 transid = btrfs_header_generation(buf);
struct inode *btree_inode = root->fs_info->btree_inode;
int was_dirty;
btrfs_assert_tree_locked(buf);
if (transid != root->fs_info->generation) {
printk(KERN_CRIT "btrfs transid mismatch buffer %llu, "
"found %llu running %llu\n",
(unsigned long long)buf->start,
(unsigned long long)transid,
(unsigned long long)root->fs_info->generation);
WARN_ON(1);
}
was_dirty = set_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
buf);
if (!was_dirty) {
spin_lock(&root->fs_info->delalloc_lock);
root->fs_info->dirty_metadata_bytes += buf->len;
spin_unlock(&root->fs_info->delalloc_lock);
}
}
void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
{
/*
* looks as though older kernels can get into trouble with
* this code, they end up stuck in balance_dirty_pages forever
*/
u64 num_dirty;
unsigned long thresh = 32 * 1024 * 1024;
if (current->flags & PF_MEMALLOC)
return;
btrfs_balance_delayed_items(root);
num_dirty = root->fs_info->dirty_metadata_bytes;
if (num_dirty > thresh) {
balance_dirty_pages_ratelimited_nr(
root->fs_info->btree_inode->i_mapping, 1);
}
return;
}
void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
{
/*
* looks as though older kernels can get into trouble with
* this code, they end up stuck in balance_dirty_pages forever
*/
u64 num_dirty;
unsigned long thresh = 32 * 1024 * 1024;
if (current->flags & PF_MEMALLOC) return;
num_dirty = root->fs_info->dirty_metadata_bytes;
if (num_dirty > thresh) {
balance_dirty_pages_ratelimited_nr(
root->fs_info->btree_inode->i_mapping, 1);
}
return;
}
int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid)
{
struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
int ret;
ret = btree_read_extent_buffer_pages(root, buf, 0, parent_transid);
if (ret == 0)
set_bit(EXTENT_BUFFER_UPTODATE, &buf->bflags);
return ret;
}
static int btree_lock_page_hook(struct page *page, void *data,
void (*flush_fn)(void *))
{
struct inode *inode = page->mapping->host;
struct btrfs_root *root = BTRFS_I(inode)->root;
struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
struct extent_buffer *eb;
unsigned long len;
u64 bytenr = page_offset(page);
if (page->private == EXTENT_PAGE_PRIVATE)
goto out;
len = page->private >> 2;
eb = find_extent_buffer(io_tree, bytenr, len);
if (!eb)
goto out;
if (!btrfs_try_tree_write_lock(eb)) {
flush_fn(data);
btrfs_tree_lock(eb);
}
btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
spin_lock(&root->fs_info->delalloc_lock);
if (root->fs_info->dirty_metadata_bytes >= eb->len)
root->fs_info->dirty_metadata_bytes -= eb->len;
else
WARN_ON(1);
spin_unlock(&root->fs_info->delalloc_lock);
}
btrfs_tree_unlock(eb);
free_extent_buffer(eb);
out:
if (!trylock_page(page)) {
flush_fn(data);
lock_page(page);
}
return 0;
}
static void btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
int read_only)
{
if (read_only)
return;
if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
printk(KERN_WARNING "warning: mount fs with errors, "
"running btrfsck is recommended\n");
}
int btrfs_error_commit_super(struct btrfs_root *root)
{
int ret;
mutex_lock(&root->fs_info->cleaner_mutex);
btrfs_run_delayed_iputs(root);
mutex_unlock(&root->fs_info->cleaner_mutex);
down_write(&root->fs_info->cleanup_work_sem);
up_write(&root->fs_info->cleanup_work_sem);
/* cleanup FS via transaction */
btrfs_cleanup_transaction(root);
ret = write_ctree_super(NULL, root, 0);
return ret;
}
static int btrfs_destroy_ordered_operations(struct btrfs_root *root)
{
struct btrfs_inode *btrfs_inode;
struct list_head splice;
INIT_LIST_HEAD(&splice);
mutex_lock(&root->fs_info->ordered_operations_mutex);
spin_lock(&root->fs_info->ordered_extent_lock);
list_splice_init(&root->fs_info->ordered_operations, &splice);
while (!list_empty(&splice)) {
btrfs_inode = list_entry(splice.next, struct btrfs_inode,
ordered_operations);
list_del_init(&btrfs_inode->ordered_operations);
btrfs_invalidate_inodes(btrfs_inode->root);
}
spin_unlock(&root->fs_info->ordered_extent_lock);
mutex_unlock(&root->fs_info->ordered_operations_mutex);
return 0;
}
static int btrfs_destroy_ordered_extents(struct btrfs_root *root)
{
struct list_head splice;
struct btrfs_ordered_extent *ordered;
struct inode *inode;
INIT_LIST_HEAD(&splice);
spin_lock(&root->fs_info->ordered_extent_lock);
list_splice_init(&root->fs_info->ordered_extents, &splice);
while (!list_empty(&splice)) {
ordered = list_entry(splice.next, struct btrfs_ordered_extent,
root_extent_list);
list_del_init(&ordered->root_extent_list);
atomic_inc(&ordered->refs);
/* the inode may be getting freed (in sys_unlink path). */
inode = igrab(ordered->inode);
spin_unlock(&root->fs_info->ordered_extent_lock);
if (inode)
iput(inode);
atomic_set(&ordered->refs, 1);
btrfs_put_ordered_extent(ordered);
spin_lock(&root->fs_info->ordered_extent_lock);
}
spin_unlock(&root->fs_info->ordered_extent_lock);
return 0;
}
static int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
struct btrfs_root *root)
{
struct rb_node *node;
struct btrfs_delayed_ref_root *delayed_refs;
struct btrfs_delayed_ref_node *ref;
int ret = 0;
delayed_refs = &trans->delayed_refs;
spin_lock(&delayed_refs->lock);
if (delayed_refs->num_entries == 0) {
spin_unlock(&delayed_refs->lock);
printk(KERN_INFO "delayed_refs has NO entry\n");
return ret;
}
node = rb_first(&delayed_refs->root);
while (node) {
ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
node = rb_next(node);
ref->in_tree = 0;
rb_erase(&ref->rb_node, &delayed_refs->root);
delayed_refs->num_entries--;
atomic_set(&ref->refs, 1);
if (btrfs_delayed_ref_is_head(ref)) {
struct btrfs_delayed_ref_head *head;
head = btrfs_delayed_node_to_head(ref);
mutex_lock(&head->mutex);
kfree(head->extent_op);
delayed_refs->num_heads--;
if (list_empty(&head->cluster))
delayed_refs->num_heads_ready--;
list_del_init(&head->cluster);
mutex_unlock(&head->mutex);
}
spin_unlock(&delayed_refs->lock);
btrfs_put_delayed_ref(ref);
cond_resched();
spin_lock(&delayed_refs->lock);
}
spin_unlock(&delayed_refs->lock);
return ret;
}
static int btrfs_destroy_pending_snapshots(struct btrfs_transaction *t)
{ struct btrfs_pending_snapshot *snapshot;
struct list_head splice;
INIT_LIST_HEAD(&splice);
list_splice_init(&t->pending_snapshots, &splice);
while (!list_empty(&splice)) {
snapshot = list_entry(splice.next,
struct btrfs_pending_snapshot,
list);
list_del_init(&snapshot->list);
kfree(snapshot);
}
return 0;
}
static int btrfs_destroy_delalloc_inodes(struct btrfs_root *root)
{
struct btrfs_inode *btrfs_inode;
struct list_head splice;
INIT_LIST_HEAD(&splice);
spin_lock(&root->fs_info->delalloc_lock);
list_splice_init(&root->fs_info->delalloc_inodes, &splice);
while (!list_empty(&splice)) {
btrfs_inode = list_entry(splice.next, struct btrfs_inode,
delalloc_inodes);
list_del_init(&btrfs_inode->delalloc_inodes);
btrfs_invalidate_inodes(btrfs_inode->root);
}
spin_unlock(&root->fs_info->delalloc_lock);
return 0;
}
static int btrfs_destroy_marked_extents(struct btrfs_root *root,
struct extent_io_tree *dirty_pages,
int mark)
{
int ret;
struct page *page;
struct inode *btree_inode = root->fs_info->btree_inode;
struct extent_buffer *eb;
u64 start = 0;
u64 end;
u64 offset;
unsigned long index;
while (1) {
ret = find_first_extent_bit(dirty_pages, start, &start, &end,
mark);
if (ret)
break;
clear_extent_bits(dirty_pages, start, end, mark, GFP_NOFS);
while (start <= end) {
index = start >> PAGE_CACHE_SHIFT;
start = (u64)(index + 1) << PAGE_CACHE_SHIFT;
page = find_get_page(btree_inode->i_mapping, index);
if (!page)
continue; offset = page_offset(page);
spin_lock(&dirty_pages->buffer_lock);
eb = radix_tree_lookup(
&(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
offset >> PAGE_CACHE_SHIFT);
spin_unlock(&dirty_pages->buffer_lock);
if (eb) {
ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
&eb->bflags);
atomic_set(&eb->refs, 1);
}
if (PageWriteback(page))
end_page_writeback(page);
lock_page(page);
if (PageDirty(page)) {
clear_page_dirty_for_io(page);
spin_lock_irq(&page->mapping->tree_lock);
radix_tree_tag_clear(&page->mapping->page_tree,
page_index(page),
PAGECACHE_TAG_DIRTY);
spin_unlock_irq(&page->mapping->tree_lock);
}
page->mapping->a_ops->invalidatepage(page, 0);
unlock_page(page);
}
}
return ret;
}
static int btrfs_destroy_pinned_extent(struct btrfs_root *root,
struct extent_io_tree *pinned_extents)
{
struct extent_io_tree *unpin;
u64 start;
u64 end;
int ret;
unpin = pinned_extents;
while (1) {
ret = find_first_extent_bit(unpin, 0, &start, &end,
EXTENT_DIRTY);
if (ret)
break;
/* opt_discard */
if (btrfs_test_opt(root, DISCARD))
ret = btrfs_error_discard_extent(root, start,
end + 1 - start,
NULL);
clear_extent_dirty(unpin, start, end, GFP_NOFS);
btrfs_error_unpin_extent_range(root, start, end);
cond_resched();
}
return 0;
}
static int btrfs_cleanup_transaction(struct btrfs_root *root)
{
struct btrfs_transaction *t;
LIST_HEAD(list);
WARN_ON(1);
mutex_lock(&root->fs_info->transaction_kthread_mutex);
spin_lock(&root->fs_info->trans_lock);
list_splice_init(&root->fs_info->trans_list, &list);
root->fs_info->trans_no_join = 1;
spin_unlock(&root->fs_info->trans_lock);
while (!list_empty(&list)) {
t = list_entry(list.next, struct btrfs_transaction, list);
if (!t)
break;
btrfs_destroy_ordered_operations(root);
btrfs_destroy_ordered_extents(root);
btrfs_destroy_delayed_refs(t, root);
btrfs_block_rsv_release(root,
&root->fs_info->trans_block_rsv,
t->dirty_pages.dirty_bytes);
/* FIXME: cleanup wait for commit */
t->in_commit = 1;
t->blocked = 1;
if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
wake_up(&root->fs_info->transaction_blocked_wait);
t->blocked = 0;
if (waitqueue_active(&root->fs_info->transaction_wait))
wake_up(&root->fs_info->transaction_wait);
t->commit_done = 1;
if (waitqueue_active(&t->commit_wait))
wake_up(&t->commit_wait);
btrfs_destroy_pending_snapshots(t);
btrfs_destroy_delalloc_inodes(root);
spin_lock(&root->fs_info->trans_lock);
root->fs_info->running_transaction = NULL;
spin_unlock(&root->fs_info->trans_lock);
btrfs_destroy_marked_extents(root, &t->dirty_pages,
EXTENT_DIRTY);
btrfs_destroy_pinned_extent(root,
root->fs_info->pinned_extents);
atomic_set(&t->use_count, 0);
list_del_init(&t->list);
memset(t, 0, sizeof(*t));
kmem_cache_free(btrfs_transaction_cachep, t);
}
spin_lock(&root->fs_info->trans_lock);
root->fs_info->trans_no_join = 0;
spin_unlock(&root->fs_info->trans_lock);
mutex_unlock(&root->fs_info->transaction_kthread_mutex);
return 0;
}
static struct extent_io_ops btree_extent_io_ops = {
.write_cache_pages_lock_hook = btree_lock_page_hook,
.readpage_end_io_hook = btree_readpage_end_io_hook,
.readpage_io_failed_hook = btree_io_failed_hook,
.submit_bio_hook = btree_submit_bio_hook,
/* note we're sharing with inode.c for the merge bio hook */
.merge_bio_hook = btrfs_merge_bio_hook,};