linux/fs/btrfs/scrub.c
Arne Jansen 859acaf1a2 btrfs: don't check DUP chunks twice
Because scrub enumerates the dev extent tree to find the chunks to scrub,
it currently finds each DUP chunk twice and also scrubs it twice. This
patch makes sure that scrub_chunk only checks that part of the chunk the
dev extent has been found for. This only changes the behaviour for DUP
chunks.

Reported-and-tested-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-02-15 16:40:24 +01:00

1782 lines
44 KiB
C

/*
* Copyright (C) 2011 STRATO. 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/blkdev.h>
#include <linux/ratelimit.h>
#include "ctree.h"
#include "volumes.h"
#include "disk-io.h"
#include "ordered-data.h"
#include "transaction.h"
#include "backref.h"
#include "extent_io.h"
#include "check-integrity.h"
/*
* This is only the first step towards a full-features scrub. It reads all
* extent and super block and verifies the checksums. In case a bad checksum
* is found or the extent cannot be read, good data will be written back if
* any can be found.
*
* Future enhancements:
* - In case an unrepairable extent is encountered, track which files are
* affected and report them
* - In case of a read error on files with nodatasum, map the file and read
* the extent to trigger a writeback of the good copy
* - track and record media errors, throw out bad devices
* - add a mode to also read unallocated space
*/
struct scrub_bio;
struct scrub_page;
struct scrub_dev;
static void scrub_bio_end_io(struct bio *bio, int err);
static void scrub_checksum(struct btrfs_work *work);
static int scrub_checksum_data(struct scrub_dev *sdev,
struct scrub_page *spag, void *buffer);
static int scrub_checksum_tree_block(struct scrub_dev *sdev,
struct scrub_page *spag, u64 logical,
void *buffer);
static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer);
static int scrub_fixup_check(struct scrub_bio *sbio, int ix);
static void scrub_fixup_end_io(struct bio *bio, int err);
static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector,
struct page *page);
static void scrub_fixup(struct scrub_bio *sbio, int ix);
#define SCRUB_PAGES_PER_BIO 16 /* 64k per bio */
#define SCRUB_BIOS_PER_DEV 16 /* 1 MB per device in flight */
struct scrub_page {
u64 flags; /* extent flags */
u64 generation;
int mirror_num;
int have_csum;
u8 csum[BTRFS_CSUM_SIZE];
};
struct scrub_bio {
int index;
struct scrub_dev *sdev;
struct bio *bio;
int err;
u64 logical;
u64 physical;
struct scrub_page spag[SCRUB_PAGES_PER_BIO];
u64 count;
int next_free;
struct btrfs_work work;
};
struct scrub_dev {
struct scrub_bio *bios[SCRUB_BIOS_PER_DEV];
struct btrfs_device *dev;
int first_free;
int curr;
atomic_t in_flight;
atomic_t fixup_cnt;
spinlock_t list_lock;
wait_queue_head_t list_wait;
u16 csum_size;
struct list_head csum_list;
atomic_t cancel_req;
int readonly;
/*
* statistics
*/
struct btrfs_scrub_progress stat;
spinlock_t stat_lock;
};
struct scrub_fixup_nodatasum {
struct scrub_dev *sdev;
u64 logical;
struct btrfs_root *root;
struct btrfs_work work;
int mirror_num;
};
struct scrub_warning {
struct btrfs_path *path;
u64 extent_item_size;
char *scratch_buf;
char *msg_buf;
const char *errstr;
sector_t sector;
u64 logical;
struct btrfs_device *dev;
int msg_bufsize;
int scratch_bufsize;
};
static void scrub_free_csums(struct scrub_dev *sdev)
{
while (!list_empty(&sdev->csum_list)) {
struct btrfs_ordered_sum *sum;
sum = list_first_entry(&sdev->csum_list,
struct btrfs_ordered_sum, list);
list_del(&sum->list);
kfree(sum);
}
}
static void scrub_free_bio(struct bio *bio)
{
int i;
struct page *last_page = NULL;
if (!bio)
return;
for (i = 0; i < bio->bi_vcnt; ++i) {
if (bio->bi_io_vec[i].bv_page == last_page)
continue;
last_page = bio->bi_io_vec[i].bv_page;
__free_page(last_page);
}
bio_put(bio);
}
static noinline_for_stack void scrub_free_dev(struct scrub_dev *sdev)
{
int i;
if (!sdev)
return;
for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) {
struct scrub_bio *sbio = sdev->bios[i];
if (!sbio)
break;
scrub_free_bio(sbio->bio);
kfree(sbio);
}
scrub_free_csums(sdev);
kfree(sdev);
}
static noinline_for_stack
struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev)
{
struct scrub_dev *sdev;
int i;
struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
sdev = kzalloc(sizeof(*sdev), GFP_NOFS);
if (!sdev)
goto nomem;
sdev->dev = dev;
for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) {
struct scrub_bio *sbio;
sbio = kzalloc(sizeof(*sbio), GFP_NOFS);
if (!sbio)
goto nomem;
sdev->bios[i] = sbio;
sbio->index = i;
sbio->sdev = sdev;
sbio->count = 0;
sbio->work.func = scrub_checksum;
if (i != SCRUB_BIOS_PER_DEV-1)
sdev->bios[i]->next_free = i + 1;
else
sdev->bios[i]->next_free = -1;
}
sdev->first_free = 0;
sdev->curr = -1;
atomic_set(&sdev->in_flight, 0);
atomic_set(&sdev->fixup_cnt, 0);
atomic_set(&sdev->cancel_req, 0);
sdev->csum_size = btrfs_super_csum_size(fs_info->super_copy);
INIT_LIST_HEAD(&sdev->csum_list);
spin_lock_init(&sdev->list_lock);
spin_lock_init(&sdev->stat_lock);
init_waitqueue_head(&sdev->list_wait);
return sdev;
nomem:
scrub_free_dev(sdev);
return ERR_PTR(-ENOMEM);
}
static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx)
{
u64 isize;
u32 nlink;
int ret;
int i;
struct extent_buffer *eb;
struct btrfs_inode_item *inode_item;
struct scrub_warning *swarn = ctx;
struct btrfs_fs_info *fs_info = swarn->dev->dev_root->fs_info;
struct inode_fs_paths *ipath = NULL;
struct btrfs_root *local_root;
struct btrfs_key root_key;
root_key.objectid = root;
root_key.type = BTRFS_ROOT_ITEM_KEY;
root_key.offset = (u64)-1;
local_root = btrfs_read_fs_root_no_name(fs_info, &root_key);
if (IS_ERR(local_root)) {
ret = PTR_ERR(local_root);
goto err;
}
ret = inode_item_info(inum, 0, local_root, swarn->path);
if (ret) {
btrfs_release_path(swarn->path);
goto err;
}
eb = swarn->path->nodes[0];
inode_item = btrfs_item_ptr(eb, swarn->path->slots[0],
struct btrfs_inode_item);
isize = btrfs_inode_size(eb, inode_item);
nlink = btrfs_inode_nlink(eb, inode_item);
btrfs_release_path(swarn->path);
ipath = init_ipath(4096, local_root, swarn->path);
if (IS_ERR(ipath)) {
ret = PTR_ERR(ipath);
ipath = NULL;
goto err;
}
ret = paths_from_inode(inum, ipath);
if (ret < 0)
goto err;
/*
* we deliberately ignore the bit ipath might have been too small to
* hold all of the paths here
*/
for (i = 0; i < ipath->fspath->elem_cnt; ++i)
printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
"%s, sector %llu, root %llu, inode %llu, offset %llu, "
"length %llu, links %u (path: %s)\n", swarn->errstr,
swarn->logical, swarn->dev->name,
(unsigned long long)swarn->sector, root, inum, offset,
min(isize - offset, (u64)PAGE_SIZE), nlink,
(char *)(unsigned long)ipath->fspath->val[i]);
free_ipath(ipath);
return 0;
err:
printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
"%s, sector %llu, root %llu, inode %llu, offset %llu: path "
"resolving failed with ret=%d\n", swarn->errstr,
swarn->logical, swarn->dev->name,
(unsigned long long)swarn->sector, root, inum, offset, ret);
free_ipath(ipath);
return 0;
}
static void scrub_print_warning(const char *errstr, struct scrub_bio *sbio,
int ix)
{
struct btrfs_device *dev = sbio->sdev->dev;
struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
struct btrfs_path *path;
struct btrfs_key found_key;
struct extent_buffer *eb;
struct btrfs_extent_item *ei;
struct scrub_warning swarn;
u32 item_size;
int ret;
u64 ref_root;
u8 ref_level;
unsigned long ptr = 0;
const int bufsize = 4096;
u64 extent_item_pos;
path = btrfs_alloc_path();
swarn.scratch_buf = kmalloc(bufsize, GFP_NOFS);
swarn.msg_buf = kmalloc(bufsize, GFP_NOFS);
swarn.sector = (sbio->physical + ix * PAGE_SIZE) >> 9;
swarn.logical = sbio->logical + ix * PAGE_SIZE;
swarn.errstr = errstr;
swarn.dev = dev;
swarn.msg_bufsize = bufsize;
swarn.scratch_bufsize = bufsize;
if (!path || !swarn.scratch_buf || !swarn.msg_buf)
goto out;
ret = extent_from_logical(fs_info, swarn.logical, path, &found_key);
if (ret < 0)
goto out;
extent_item_pos = swarn.logical - found_key.objectid;
swarn.extent_item_size = found_key.offset;
eb = path->nodes[0];
ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
item_size = btrfs_item_size_nr(eb, path->slots[0]);
btrfs_release_path(path);
if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
do {
ret = tree_backref_for_extent(&ptr, eb, ei, item_size,
&ref_root, &ref_level);
printk(KERN_WARNING "%s at logical %llu on dev %s, "
"sector %llu: metadata %s (level %d) in tree "
"%llu\n", errstr, swarn.logical, dev->name,
(unsigned long long)swarn.sector,
ref_level ? "node" : "leaf",
ret < 0 ? -1 : ref_level,
ret < 0 ? -1 : ref_root);
} while (ret != 1);
} else {
swarn.path = path;
iterate_extent_inodes(fs_info, path, found_key.objectid,
extent_item_pos,
scrub_print_warning_inode, &swarn);
}
out:
btrfs_free_path(path);
kfree(swarn.scratch_buf);
kfree(swarn.msg_buf);
}
static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *ctx)
{
struct page *page = NULL;
unsigned long index;
struct scrub_fixup_nodatasum *fixup = ctx;
int ret;
int corrected = 0;
struct btrfs_key key;
struct inode *inode = NULL;
u64 end = offset + PAGE_SIZE - 1;
struct btrfs_root *local_root;
key.objectid = root;
key.type = BTRFS_ROOT_ITEM_KEY;
key.offset = (u64)-1;
local_root = btrfs_read_fs_root_no_name(fixup->root->fs_info, &key);
if (IS_ERR(local_root))
return PTR_ERR(local_root);
key.type = BTRFS_INODE_ITEM_KEY;
key.objectid = inum;
key.offset = 0;
inode = btrfs_iget(fixup->root->fs_info->sb, &key, local_root, NULL);
if (IS_ERR(inode))
return PTR_ERR(inode);
index = offset >> PAGE_CACHE_SHIFT;
page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
if (!page) {
ret = -ENOMEM;
goto out;
}
if (PageUptodate(page)) {
struct btrfs_mapping_tree *map_tree;
if (PageDirty(page)) {
/*
* we need to write the data to the defect sector. the
* data that was in that sector is not in memory,
* because the page was modified. we must not write the
* modified page to that sector.
*
* TODO: what could be done here: wait for the delalloc
* runner to write out that page (might involve
* COW) and see whether the sector is still
* referenced afterwards.
*
* For the meantime, we'll treat this error
* incorrectable, although there is a chance that a
* later scrub will find the bad sector again and that
* there's no dirty page in memory, then.
*/
ret = -EIO;
goto out;
}
map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree;
ret = repair_io_failure(map_tree, offset, PAGE_SIZE,
fixup->logical, page,
fixup->mirror_num);
unlock_page(page);
corrected = !ret;
} else {
/*
* we need to get good data first. the general readpage path
* will call repair_io_failure for us, we just have to make
* sure we read the bad mirror.
*/
ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
EXTENT_DAMAGED, GFP_NOFS);
if (ret) {
/* set_extent_bits should give proper error */
WARN_ON(ret > 0);
if (ret > 0)
ret = -EFAULT;
goto out;
}
ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page,
btrfs_get_extent,
fixup->mirror_num);
wait_on_page_locked(page);
corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset,
end, EXTENT_DAMAGED, 0, NULL);
if (!corrected)
clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
EXTENT_DAMAGED, GFP_NOFS);
}
out:
if (page)
put_page(page);
if (inode)
iput(inode);
if (ret < 0)
return ret;
if (ret == 0 && corrected) {
/*
* we only need to call readpage for one of the inodes belonging
* to this extent. so make iterate_extent_inodes stop
*/
return 1;
}
return -EIO;
}
static void scrub_fixup_nodatasum(struct btrfs_work *work)
{
int ret;
struct scrub_fixup_nodatasum *fixup;
struct scrub_dev *sdev;
struct btrfs_trans_handle *trans = NULL;
struct btrfs_fs_info *fs_info;
struct btrfs_path *path;
int uncorrectable = 0;
fixup = container_of(work, struct scrub_fixup_nodatasum, work);
sdev = fixup->sdev;
fs_info = fixup->root->fs_info;
path = btrfs_alloc_path();
if (!path) {
spin_lock(&sdev->stat_lock);
++sdev->stat.malloc_errors;
spin_unlock(&sdev->stat_lock);
uncorrectable = 1;
goto out;
}
trans = btrfs_join_transaction(fixup->root);
if (IS_ERR(trans)) {
uncorrectable = 1;
goto out;
}
/*
* the idea is to trigger a regular read through the standard path. we
* read a page from the (failed) logical address by specifying the
* corresponding copynum of the failed sector. thus, that readpage is
* expected to fail.
* that is the point where on-the-fly error correction will kick in
* (once it's finished) and rewrite the failed sector if a good copy
* can be found.
*/
ret = iterate_inodes_from_logical(fixup->logical, fixup->root->fs_info,
path, scrub_fixup_readpage,
fixup);
if (ret < 0) {
uncorrectable = 1;
goto out;
}
WARN_ON(ret != 1);
spin_lock(&sdev->stat_lock);
++sdev->stat.corrected_errors;
spin_unlock(&sdev->stat_lock);
out:
if (trans && !IS_ERR(trans))
btrfs_end_transaction(trans, fixup->root);
if (uncorrectable) {
spin_lock(&sdev->stat_lock);
++sdev->stat.uncorrectable_errors;
spin_unlock(&sdev->stat_lock);
printk_ratelimited(KERN_ERR "btrfs: unable to fixup "
"(nodatasum) error at logical %llu\n",
fixup->logical);
}
btrfs_free_path(path);
kfree(fixup);
/* see caller why we're pretending to be paused in the scrub counters */
mutex_lock(&fs_info->scrub_lock);
atomic_dec(&fs_info->scrubs_running);
atomic_dec(&fs_info->scrubs_paused);
mutex_unlock(&fs_info->scrub_lock);
atomic_dec(&sdev->fixup_cnt);
wake_up(&fs_info->scrub_pause_wait);
wake_up(&sdev->list_wait);
}
/*
* scrub_recheck_error gets called when either verification of the page
* failed or the bio failed to read, e.g. with EIO. In the latter case,
* recheck_error gets called for every page in the bio, even though only
* one may be bad
*/
static int scrub_recheck_error(struct scrub_bio *sbio, int ix)
{
struct scrub_dev *sdev = sbio->sdev;
u64 sector = (sbio->physical + ix * PAGE_SIZE) >> 9;
static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
if (sbio->err) {
if (scrub_fixup_io(READ, sbio->sdev->dev->bdev, sector,
sbio->bio->bi_io_vec[ix].bv_page) == 0) {
if (scrub_fixup_check(sbio, ix) == 0)
return 0;
}
if (__ratelimit(&_rs))
scrub_print_warning("i/o error", sbio, ix);
} else {
if (__ratelimit(&_rs))
scrub_print_warning("checksum error", sbio, ix);
}
spin_lock(&sdev->stat_lock);
++sdev->stat.read_errors;
spin_unlock(&sdev->stat_lock);
scrub_fixup(sbio, ix);
return 1;
}
static int scrub_fixup_check(struct scrub_bio *sbio, int ix)
{
int ret = 1;
struct page *page;
void *buffer;
u64 flags = sbio->spag[ix].flags;
page = sbio->bio->bi_io_vec[ix].bv_page;
buffer = kmap_atomic(page, KM_USER0);
if (flags & BTRFS_EXTENT_FLAG_DATA) {
ret = scrub_checksum_data(sbio->sdev,
sbio->spag + ix, buffer);
} else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
ret = scrub_checksum_tree_block(sbio->sdev,
sbio->spag + ix,
sbio->logical + ix * PAGE_SIZE,
buffer);
} else {
WARN_ON(1);
}
kunmap_atomic(buffer, KM_USER0);
return ret;
}
static void scrub_fixup_end_io(struct bio *bio, int err)
{
complete((struct completion *)bio->bi_private);
}
static void scrub_fixup(struct scrub_bio *sbio, int ix)
{
struct scrub_dev *sdev = sbio->sdev;
struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info;
struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
struct btrfs_bio *bbio = NULL;
struct scrub_fixup_nodatasum *fixup;
u64 logical = sbio->logical + ix * PAGE_SIZE;
u64 length;
int i;
int ret;
DECLARE_COMPLETION_ONSTACK(complete);
if ((sbio->spag[ix].flags & BTRFS_EXTENT_FLAG_DATA) &&
(sbio->spag[ix].have_csum == 0)) {
fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
if (!fixup)
goto uncorrectable;
fixup->sdev = sdev;
fixup->logical = logical;
fixup->root = fs_info->extent_root;
fixup->mirror_num = sbio->spag[ix].mirror_num;
/*
* increment scrubs_running to prevent cancel requests from
* completing as long as a fixup worker is running. we must also
* increment scrubs_paused to prevent deadlocking on pause
* requests used for transactions commits (as the worker uses a
* transaction context). it is safe to regard the fixup worker
* as paused for all matters practical. effectively, we only
* avoid cancellation requests from completing.
*/
mutex_lock(&fs_info->scrub_lock);
atomic_inc(&fs_info->scrubs_running);
atomic_inc(&fs_info->scrubs_paused);
mutex_unlock(&fs_info->scrub_lock);
atomic_inc(&sdev->fixup_cnt);
fixup->work.func = scrub_fixup_nodatasum;
btrfs_queue_worker(&fs_info->scrub_workers, &fixup->work);
return;
}
length = PAGE_SIZE;
ret = btrfs_map_block(map_tree, REQ_WRITE, logical, &length,
&bbio, 0);
if (ret || !bbio || length < PAGE_SIZE) {
printk(KERN_ERR
"scrub_fixup: btrfs_map_block failed us for %llu\n",
(unsigned long long)logical);
WARN_ON(1);
kfree(bbio);
return;
}
if (bbio->num_stripes == 1)
/* there aren't any replicas */
goto uncorrectable;
/*
* first find a good copy
*/
for (i = 0; i < bbio->num_stripes; ++i) {
if (i + 1 == sbio->spag[ix].mirror_num)
continue;
if (scrub_fixup_io(READ, bbio->stripes[i].dev->bdev,
bbio->stripes[i].physical >> 9,
sbio->bio->bi_io_vec[ix].bv_page)) {
/* I/O-error, this is not a good copy */
continue;
}
if (scrub_fixup_check(sbio, ix) == 0)
break;
}
if (i == bbio->num_stripes)
goto uncorrectable;
if (!sdev->readonly) {
/*
* bi_io_vec[ix].bv_page now contains good data, write it back
*/
if (scrub_fixup_io(WRITE, sdev->dev->bdev,
(sbio->physical + ix * PAGE_SIZE) >> 9,
sbio->bio->bi_io_vec[ix].bv_page)) {
/* I/O-error, writeback failed, give up */
goto uncorrectable;
}
}
kfree(bbio);
spin_lock(&sdev->stat_lock);
++sdev->stat.corrected_errors;
spin_unlock(&sdev->stat_lock);
printk_ratelimited(KERN_ERR "btrfs: fixed up error at logical %llu\n",
(unsigned long long)logical);
return;
uncorrectable:
kfree(bbio);
spin_lock(&sdev->stat_lock);
++sdev->stat.uncorrectable_errors;
spin_unlock(&sdev->stat_lock);
printk_ratelimited(KERN_ERR "btrfs: unable to fixup (regular) error at "
"logical %llu\n", (unsigned long long)logical);
}
static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector,
struct page *page)
{
struct bio *bio = NULL;
int ret;
DECLARE_COMPLETION_ONSTACK(complete);
bio = bio_alloc(GFP_NOFS, 1);
bio->bi_bdev = bdev;
bio->bi_sector = sector;
bio_add_page(bio, page, PAGE_SIZE, 0);
bio->bi_end_io = scrub_fixup_end_io;
bio->bi_private = &complete;
btrfsic_submit_bio(rw, bio);
/* this will also unplug the queue */
wait_for_completion(&complete);
ret = !test_bit(BIO_UPTODATE, &bio->bi_flags);
bio_put(bio);
return ret;
}
static void scrub_bio_end_io(struct bio *bio, int err)
{
struct scrub_bio *sbio = bio->bi_private;
struct scrub_dev *sdev = sbio->sdev;
struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info;
sbio->err = err;
sbio->bio = bio;
btrfs_queue_worker(&fs_info->scrub_workers, &sbio->work);
}
static void scrub_checksum(struct btrfs_work *work)
{
struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
struct scrub_dev *sdev = sbio->sdev;
struct page *page;
void *buffer;
int i;
u64 flags;
u64 logical;
int ret;
if (sbio->err) {
ret = 0;
for (i = 0; i < sbio->count; ++i)
ret |= scrub_recheck_error(sbio, i);
if (!ret) {
spin_lock(&sdev->stat_lock);
++sdev->stat.unverified_errors;
spin_unlock(&sdev->stat_lock);
}
sbio->bio->bi_flags &= ~(BIO_POOL_MASK - 1);
sbio->bio->bi_flags |= 1 << BIO_UPTODATE;
sbio->bio->bi_phys_segments = 0;
sbio->bio->bi_idx = 0;
for (i = 0; i < sbio->count; i++) {
struct bio_vec *bi;
bi = &sbio->bio->bi_io_vec[i];
bi->bv_offset = 0;
bi->bv_len = PAGE_SIZE;
}
goto out;
}
for (i = 0; i < sbio->count; ++i) {
page = sbio->bio->bi_io_vec[i].bv_page;
buffer = kmap_atomic(page, KM_USER0);
flags = sbio->spag[i].flags;
logical = sbio->logical + i * PAGE_SIZE;
ret = 0;
if (flags & BTRFS_EXTENT_FLAG_DATA) {
ret = scrub_checksum_data(sdev, sbio->spag + i, buffer);
} else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
ret = scrub_checksum_tree_block(sdev, sbio->spag + i,
logical, buffer);
} else if (flags & BTRFS_EXTENT_FLAG_SUPER) {
BUG_ON(i);
(void)scrub_checksum_super(sbio, buffer);
} else {
WARN_ON(1);
}
kunmap_atomic(buffer, KM_USER0);
if (ret) {
ret = scrub_recheck_error(sbio, i);
if (!ret) {
spin_lock(&sdev->stat_lock);
++sdev->stat.unverified_errors;
spin_unlock(&sdev->stat_lock);
}
}
}
out:
scrub_free_bio(sbio->bio);
sbio->bio = NULL;
spin_lock(&sdev->list_lock);
sbio->next_free = sdev->first_free;
sdev->first_free = sbio->index;
spin_unlock(&sdev->list_lock);
atomic_dec(&sdev->in_flight);
wake_up(&sdev->list_wait);
}
static int scrub_checksum_data(struct scrub_dev *sdev,
struct scrub_page *spag, void *buffer)
{
u8 csum[BTRFS_CSUM_SIZE];
u32 crc = ~(u32)0;
int fail = 0;
struct btrfs_root *root = sdev->dev->dev_root;
if (!spag->have_csum)
return 0;
crc = btrfs_csum_data(root, buffer, crc, PAGE_SIZE);
btrfs_csum_final(crc, csum);
if (memcmp(csum, spag->csum, sdev->csum_size))
fail = 1;
spin_lock(&sdev->stat_lock);
++sdev->stat.data_extents_scrubbed;
sdev->stat.data_bytes_scrubbed += PAGE_SIZE;
if (fail)
++sdev->stat.csum_errors;
spin_unlock(&sdev->stat_lock);
return fail;
}
static int scrub_checksum_tree_block(struct scrub_dev *sdev,
struct scrub_page *spag, u64 logical,
void *buffer)
{
struct btrfs_header *h;
struct btrfs_root *root = sdev->dev->dev_root;
struct btrfs_fs_info *fs_info = root->fs_info;
u8 csum[BTRFS_CSUM_SIZE];
u32 crc = ~(u32)0;
int fail = 0;
int crc_fail = 0;
/*
* we don't use the getter functions here, as we
* a) don't have an extent buffer and
* b) the page is already kmapped
*/
h = (struct btrfs_header *)buffer;
if (logical != le64_to_cpu(h->bytenr))
++fail;
if (spag->generation != le64_to_cpu(h->generation))
++fail;
if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
++fail;
if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
BTRFS_UUID_SIZE))
++fail;
crc = btrfs_csum_data(root, buffer + BTRFS_CSUM_SIZE, crc,
PAGE_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, csum);
if (memcmp(csum, h->csum, sdev->csum_size))
++crc_fail;
spin_lock(&sdev->stat_lock);
++sdev->stat.tree_extents_scrubbed;
sdev->stat.tree_bytes_scrubbed += PAGE_SIZE;
if (crc_fail)
++sdev->stat.csum_errors;
if (fail)
++sdev->stat.verify_errors;
spin_unlock(&sdev->stat_lock);
return fail || crc_fail;
}
static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer)
{
struct btrfs_super_block *s;
u64 logical;
struct scrub_dev *sdev = sbio->sdev;
struct btrfs_root *root = sdev->dev->dev_root;
struct btrfs_fs_info *fs_info = root->fs_info;
u8 csum[BTRFS_CSUM_SIZE];
u32 crc = ~(u32)0;
int fail = 0;
s = (struct btrfs_super_block *)buffer;
logical = sbio->logical;
if (logical != le64_to_cpu(s->bytenr))
++fail;
if (sbio->spag[0].generation != le64_to_cpu(s->generation))
++fail;
if (memcmp(s->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
++fail;
crc = btrfs_csum_data(root, buffer + BTRFS_CSUM_SIZE, crc,
PAGE_SIZE - BTRFS_CSUM_SIZE);
btrfs_csum_final(crc, csum);
if (memcmp(csum, s->csum, sbio->sdev->csum_size))
++fail;
if (fail) {
/*
* if we find an error in a super block, we just report it.
* They will get written with the next transaction commit
* anyway
*/
spin_lock(&sdev->stat_lock);
++sdev->stat.super_errors;
spin_unlock(&sdev->stat_lock);
}
return fail;
}
static int scrub_submit(struct scrub_dev *sdev)
{
struct scrub_bio *sbio;
if (sdev->curr == -1)
return 0;
sbio = sdev->bios[sdev->curr];
sbio->err = 0;
sdev->curr = -1;
atomic_inc(&sdev->in_flight);
btrfsic_submit_bio(READ, sbio->bio);
return 0;
}
static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len,
u64 physical, u64 flags, u64 gen, int mirror_num,
u8 *csum, int force)
{
struct scrub_bio *sbio;
struct page *page;
int ret;
again:
/*
* grab a fresh bio or wait for one to become available
*/
while (sdev->curr == -1) {
spin_lock(&sdev->list_lock);
sdev->curr = sdev->first_free;
if (sdev->curr != -1) {
sdev->first_free = sdev->bios[sdev->curr]->next_free;
sdev->bios[sdev->curr]->next_free = -1;
sdev->bios[sdev->curr]->count = 0;
spin_unlock(&sdev->list_lock);
} else {
spin_unlock(&sdev->list_lock);
wait_event(sdev->list_wait, sdev->first_free != -1);
}
}
sbio = sdev->bios[sdev->curr];
if (sbio->count == 0) {
struct bio *bio;
sbio->physical = physical;
sbio->logical = logical;
bio = bio_alloc(GFP_NOFS, SCRUB_PAGES_PER_BIO);
if (!bio)
return -ENOMEM;
bio->bi_private = sbio;
bio->bi_end_io = scrub_bio_end_io;
bio->bi_bdev = sdev->dev->bdev;
bio->bi_sector = sbio->physical >> 9;
sbio->err = 0;
sbio->bio = bio;
} else if (sbio->physical + sbio->count * PAGE_SIZE != physical ||
sbio->logical + sbio->count * PAGE_SIZE != logical) {
ret = scrub_submit(sdev);
if (ret)
return ret;
goto again;
}
sbio->spag[sbio->count].flags = flags;
sbio->spag[sbio->count].generation = gen;
sbio->spag[sbio->count].have_csum = 0;
sbio->spag[sbio->count].mirror_num = mirror_num;
page = alloc_page(GFP_NOFS);
if (!page)
return -ENOMEM;
ret = bio_add_page(sbio->bio, page, PAGE_SIZE, 0);
if (!ret) {
__free_page(page);
ret = scrub_submit(sdev);
if (ret)
return ret;
goto again;
}
if (csum) {
sbio->spag[sbio->count].have_csum = 1;
memcpy(sbio->spag[sbio->count].csum, csum, sdev->csum_size);
}
++sbio->count;
if (sbio->count == SCRUB_PAGES_PER_BIO || force) {
int ret;
ret = scrub_submit(sdev);
if (ret)
return ret;
}
return 0;
}
static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len,
u8 *csum)
{
struct btrfs_ordered_sum *sum = NULL;
int ret = 0;
unsigned long i;
unsigned long num_sectors;
u32 sectorsize = sdev->dev->dev_root->sectorsize;
while (!list_empty(&sdev->csum_list)) {
sum = list_first_entry(&sdev->csum_list,
struct btrfs_ordered_sum, list);
if (sum->bytenr > logical)
return 0;
if (sum->bytenr + sum->len > logical)
break;
++sdev->stat.csum_discards;
list_del(&sum->list);
kfree(sum);
sum = NULL;
}
if (!sum)
return 0;
num_sectors = sum->len / sectorsize;
for (i = 0; i < num_sectors; ++i) {
if (sum->sums[i].bytenr == logical) {
memcpy(csum, &sum->sums[i].sum, sdev->csum_size);
ret = 1;
break;
}
}
if (ret && i == num_sectors - 1) {
list_del(&sum->list);
kfree(sum);
}
return ret;
}
/* scrub extent tries to collect up to 64 kB for each bio */
static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len,
u64 physical, u64 flags, u64 gen, int mirror_num)
{
int ret;
u8 csum[BTRFS_CSUM_SIZE];
while (len) {
u64 l = min_t(u64, len, PAGE_SIZE);
int have_csum = 0;
if (flags & BTRFS_EXTENT_FLAG_DATA) {
/* push csums to sbio */
have_csum = scrub_find_csum(sdev, logical, l, csum);
if (have_csum == 0)
++sdev->stat.no_csum;
}
ret = scrub_page(sdev, logical, l, physical, flags, gen,
mirror_num, have_csum ? csum : NULL, 0);
if (ret)
return ret;
len -= l;
logical += l;
physical += l;
}
return 0;
}
static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev,
struct map_lookup *map, int num, u64 base, u64 length)
{
struct btrfs_path *path;
struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info;
struct btrfs_root *root = fs_info->extent_root;
struct btrfs_root *csum_root = fs_info->csum_root;
struct btrfs_extent_item *extent;
struct blk_plug plug;
u64 flags;
int ret;
int slot;
int i;
u64 nstripes;
struct extent_buffer *l;
struct btrfs_key key;
u64 physical;
u64 logical;
u64 generation;
int mirror_num;
struct reada_control *reada1;
struct reada_control *reada2;
struct btrfs_key key_start;
struct btrfs_key key_end;
u64 increment = map->stripe_len;
u64 offset;
nstripes = length;
offset = 0;
do_div(nstripes, map->stripe_len);
if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
offset = map->stripe_len * num;
increment = map->stripe_len * map->num_stripes;
mirror_num = 1;
} else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
int factor = map->num_stripes / map->sub_stripes;
offset = map->stripe_len * (num / map->sub_stripes);
increment = map->stripe_len * factor;
mirror_num = num % map->sub_stripes + 1;
} else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
increment = map->stripe_len;
mirror_num = num % map->num_stripes + 1;
} else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
increment = map->stripe_len;
mirror_num = num % map->num_stripes + 1;
} else {
increment = map->stripe_len;
mirror_num = 1;
}
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->search_commit_root = 1;
path->skip_locking = 1;
/*
* trigger the readahead for extent tree csum tree and wait for
* completion. During readahead, the scrub is officially paused
* to not hold off transaction commits
*/
logical = base + offset;
wait_event(sdev->list_wait,
atomic_read(&sdev->in_flight) == 0);
atomic_inc(&fs_info->scrubs_paused);
wake_up(&fs_info->scrub_pause_wait);
/* FIXME it might be better to start readahead at commit root */
key_start.objectid = logical;
key_start.type = BTRFS_EXTENT_ITEM_KEY;
key_start.offset = (u64)0;
key_end.objectid = base + offset + nstripes * increment;
key_end.type = BTRFS_EXTENT_ITEM_KEY;
key_end.offset = (u64)0;
reada1 = btrfs_reada_add(root, &key_start, &key_end);
key_start.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
key_start.type = BTRFS_EXTENT_CSUM_KEY;
key_start.offset = logical;
key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
key_end.type = BTRFS_EXTENT_CSUM_KEY;
key_end.offset = base + offset + nstripes * increment;
reada2 = btrfs_reada_add(csum_root, &key_start, &key_end);
if (!IS_ERR(reada1))
btrfs_reada_wait(reada1);
if (!IS_ERR(reada2))
btrfs_reada_wait(reada2);
mutex_lock(&fs_info->scrub_lock);
while (atomic_read(&fs_info->scrub_pause_req)) {
mutex_unlock(&fs_info->scrub_lock);
wait_event(fs_info->scrub_pause_wait,
atomic_read(&fs_info->scrub_pause_req) == 0);
mutex_lock(&fs_info->scrub_lock);
}
atomic_dec(&fs_info->scrubs_paused);
mutex_unlock(&fs_info->scrub_lock);
wake_up(&fs_info->scrub_pause_wait);
/*
* collect all data csums for the stripe to avoid seeking during
* the scrub. This might currently (crc32) end up to be about 1MB
*/
blk_start_plug(&plug);
/*
* now find all extents for each stripe and scrub them
*/
logical = base + offset;
physical = map->stripes[num].physical;
ret = 0;
for (i = 0; i < nstripes; ++i) {
/*
* canceled?
*/
if (atomic_read(&fs_info->scrub_cancel_req) ||
atomic_read(&sdev->cancel_req)) {
ret = -ECANCELED;
goto out;
}
/*
* check to see if we have to pause
*/
if (atomic_read(&fs_info->scrub_pause_req)) {
/* push queued extents */
scrub_submit(sdev);
wait_event(sdev->list_wait,
atomic_read(&sdev->in_flight) == 0);
atomic_inc(&fs_info->scrubs_paused);
wake_up(&fs_info->scrub_pause_wait);
mutex_lock(&fs_info->scrub_lock);
while (atomic_read(&fs_info->scrub_pause_req)) {
mutex_unlock(&fs_info->scrub_lock);
wait_event(fs_info->scrub_pause_wait,
atomic_read(&fs_info->scrub_pause_req) == 0);
mutex_lock(&fs_info->scrub_lock);
}
atomic_dec(&fs_info->scrubs_paused);
mutex_unlock(&fs_info->scrub_lock);
wake_up(&fs_info->scrub_pause_wait);
}
ret = btrfs_lookup_csums_range(csum_root, logical,
logical + map->stripe_len - 1,
&sdev->csum_list, 1);
if (ret)
goto out;
key.objectid = logical;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = (u64)0;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
if (ret > 0) {
ret = btrfs_previous_item(root, path, 0,
BTRFS_EXTENT_ITEM_KEY);
if (ret < 0)
goto out;
if (ret > 0) {
/* there's no smaller item, so stick with the
* larger one */
btrfs_release_path(path);
ret = btrfs_search_slot(NULL, root, &key,
path, 0, 0);
if (ret < 0)
goto out;
}
}
while (1) {
l = path->nodes[0];
slot = path->slots[0];
if (slot >= btrfs_header_nritems(l)) {
ret = btrfs_next_leaf(root, path);
if (ret == 0)
continue;
if (ret < 0)
goto out;
break;
}
btrfs_item_key_to_cpu(l, &key, slot);
if (key.objectid + key.offset <= logical)
goto next;
if (key.objectid >= logical + map->stripe_len)
break;
if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY)
goto next;
extent = btrfs_item_ptr(l, slot,
struct btrfs_extent_item);
flags = btrfs_extent_flags(l, extent);
generation = btrfs_extent_generation(l, extent);
if (key.objectid < logical &&
(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
printk(KERN_ERR
"btrfs scrub: tree block %llu spanning "
"stripes, ignored. logical=%llu\n",
(unsigned long long)key.objectid,
(unsigned long long)logical);
goto next;
}
/*
* trim extent to this stripe
*/
if (key.objectid < logical) {
key.offset -= logical - key.objectid;
key.objectid = logical;
}
if (key.objectid + key.offset >
logical + map->stripe_len) {
key.offset = logical + map->stripe_len -
key.objectid;
}
ret = scrub_extent(sdev, key.objectid, key.offset,
key.objectid - logical + physical,
flags, generation, mirror_num);
if (ret)
goto out;
next:
path->slots[0]++;
}
btrfs_release_path(path);
logical += increment;
physical += map->stripe_len;
spin_lock(&sdev->stat_lock);
sdev->stat.last_physical = physical;
spin_unlock(&sdev->stat_lock);
}
/* push queued extents */
scrub_submit(sdev);
out:
blk_finish_plug(&plug);
btrfs_free_path(path);
return ret < 0 ? ret : 0;
}
static noinline_for_stack int scrub_chunk(struct scrub_dev *sdev,
u64 chunk_tree, u64 chunk_objectid, u64 chunk_offset, u64 length,
u64 dev_offset)
{
struct btrfs_mapping_tree *map_tree =
&sdev->dev->dev_root->fs_info->mapping_tree;
struct map_lookup *map;
struct extent_map *em;
int i;
int ret = -EINVAL;
read_lock(&map_tree->map_tree.lock);
em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
read_unlock(&map_tree->map_tree.lock);
if (!em)
return -EINVAL;
map = (struct map_lookup *)em->bdev;
if (em->start != chunk_offset)
goto out;
if (em->len < length)
goto out;
for (i = 0; i < map->num_stripes; ++i) {
if (map->stripes[i].dev == sdev->dev &&
map->stripes[i].physical == dev_offset) {
ret = scrub_stripe(sdev, map, i, chunk_offset, length);
if (ret)
goto out;
}
}
out:
free_extent_map(em);
return ret;
}
static noinline_for_stack
int scrub_enumerate_chunks(struct scrub_dev *sdev, u64 start, u64 end)
{
struct btrfs_dev_extent *dev_extent = NULL;
struct btrfs_path *path;
struct btrfs_root *root = sdev->dev->dev_root;
struct btrfs_fs_info *fs_info = root->fs_info;
u64 length;
u64 chunk_tree;
u64 chunk_objectid;
u64 chunk_offset;
int ret;
int slot;
struct extent_buffer *l;
struct btrfs_key key;
struct btrfs_key found_key;
struct btrfs_block_group_cache *cache;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 2;
path->search_commit_root = 1;
path->skip_locking = 1;
key.objectid = sdev->dev->devid;
key.offset = 0ull;
key.type = BTRFS_DEV_EXTENT_KEY;
while (1) {
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
break;
if (ret > 0) {
if (path->slots[0] >=
btrfs_header_nritems(path->nodes[0])) {
ret = btrfs_next_leaf(root, path);
if (ret)
break;
}
}
l = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(l, &found_key, slot);
if (found_key.objectid != sdev->dev->devid)
break;
if (btrfs_key_type(&found_key) != BTRFS_DEV_EXTENT_KEY)
break;
if (found_key.offset >= end)
break;
if (found_key.offset < key.offset)
break;
dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
length = btrfs_dev_extent_length(l, dev_extent);
if (found_key.offset + length <= start) {
key.offset = found_key.offset + length;
btrfs_release_path(path);
continue;
}
chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
/*
* get a reference on the corresponding block group to prevent
* the chunk from going away while we scrub it
*/
cache = btrfs_lookup_block_group(fs_info, chunk_offset);
if (!cache) {
ret = -ENOENT;
break;
}
ret = scrub_chunk(sdev, chunk_tree, chunk_objectid,
chunk_offset, length, found_key.offset);
btrfs_put_block_group(cache);
if (ret)
break;
key.offset = found_key.offset + length;
btrfs_release_path(path);
}
btrfs_free_path(path);
/*
* ret can still be 1 from search_slot or next_leaf,
* that's not an error
*/
return ret < 0 ? ret : 0;
}
static noinline_for_stack int scrub_supers(struct scrub_dev *sdev)
{
int i;
u64 bytenr;
u64 gen;
int ret;
struct btrfs_device *device = sdev->dev;
struct btrfs_root *root = device->dev_root;
gen = root->fs_info->last_trans_committed;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
bytenr = btrfs_sb_offset(i);
if (bytenr + BTRFS_SUPER_INFO_SIZE >= device->total_bytes)
break;
ret = scrub_page(sdev, bytenr, PAGE_SIZE, bytenr,
BTRFS_EXTENT_FLAG_SUPER, gen, i, NULL, 1);
if (ret)
return ret;
}
wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0);
return 0;
}
/*
* get a reference count on fs_info->scrub_workers. start worker if necessary
*/
static noinline_for_stack int scrub_workers_get(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
int ret = 0;
mutex_lock(&fs_info->scrub_lock);
if (fs_info->scrub_workers_refcnt == 0) {
btrfs_init_workers(&fs_info->scrub_workers, "scrub",
fs_info->thread_pool_size, &fs_info->generic_worker);
fs_info->scrub_workers.idle_thresh = 4;
ret = btrfs_start_workers(&fs_info->scrub_workers);
if (ret)
goto out;
}
++fs_info->scrub_workers_refcnt;
out:
mutex_unlock(&fs_info->scrub_lock);
return ret;
}
static noinline_for_stack void scrub_workers_put(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
mutex_lock(&fs_info->scrub_lock);
if (--fs_info->scrub_workers_refcnt == 0)
btrfs_stop_workers(&fs_info->scrub_workers);
WARN_ON(fs_info->scrub_workers_refcnt < 0);
mutex_unlock(&fs_info->scrub_lock);
}
int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end,
struct btrfs_scrub_progress *progress, int readonly)
{
struct scrub_dev *sdev;
struct btrfs_fs_info *fs_info = root->fs_info;
int ret;
struct btrfs_device *dev;
if (btrfs_fs_closing(root->fs_info))
return -EINVAL;
/*
* check some assumptions
*/
if (root->sectorsize != PAGE_SIZE ||
root->sectorsize != root->leafsize ||
root->sectorsize != root->nodesize) {
printk(KERN_ERR "btrfs_scrub: size assumptions fail\n");
return -EINVAL;
}
ret = scrub_workers_get(root);
if (ret)
return ret;
mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
dev = btrfs_find_device(root, devid, NULL, NULL);
if (!dev || dev->missing) {
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
scrub_workers_put(root);
return -ENODEV;
}
mutex_lock(&fs_info->scrub_lock);
if (!dev->in_fs_metadata) {
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
scrub_workers_put(root);
return -ENODEV;
}
if (dev->scrub_device) {
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
scrub_workers_put(root);
return -EINPROGRESS;
}
sdev = scrub_setup_dev(dev);
if (IS_ERR(sdev)) {
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
scrub_workers_put(root);
return PTR_ERR(sdev);
}
sdev->readonly = readonly;
dev->scrub_device = sdev;
atomic_inc(&fs_info->scrubs_running);
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
down_read(&fs_info->scrub_super_lock);
ret = scrub_supers(sdev);
up_read(&fs_info->scrub_super_lock);
if (!ret)
ret = scrub_enumerate_chunks(sdev, start, end);
wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0);
atomic_dec(&fs_info->scrubs_running);
wake_up(&fs_info->scrub_pause_wait);
wait_event(sdev->list_wait, atomic_read(&sdev->fixup_cnt) == 0);
if (progress)
memcpy(progress, &sdev->stat, sizeof(*progress));
mutex_lock(&fs_info->scrub_lock);
dev->scrub_device = NULL;
mutex_unlock(&fs_info->scrub_lock);
scrub_free_dev(sdev);
scrub_workers_put(root);
return ret;
}
int btrfs_scrub_pause(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
mutex_lock(&fs_info->scrub_lock);
atomic_inc(&fs_info->scrub_pause_req);
while (atomic_read(&fs_info->scrubs_paused) !=
atomic_read(&fs_info->scrubs_running)) {
mutex_unlock(&fs_info->scrub_lock);
wait_event(fs_info->scrub_pause_wait,
atomic_read(&fs_info->scrubs_paused) ==
atomic_read(&fs_info->scrubs_running));
mutex_lock(&fs_info->scrub_lock);
}
mutex_unlock(&fs_info->scrub_lock);
return 0;
}
int btrfs_scrub_continue(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
atomic_dec(&fs_info->scrub_pause_req);
wake_up(&fs_info->scrub_pause_wait);
return 0;
}
int btrfs_scrub_pause_super(struct btrfs_root *root)
{
down_write(&root->fs_info->scrub_super_lock);
return 0;
}
int btrfs_scrub_continue_super(struct btrfs_root *root)
{
up_write(&root->fs_info->scrub_super_lock);
return 0;
}
int btrfs_scrub_cancel(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
mutex_lock(&fs_info->scrub_lock);
if (!atomic_read(&fs_info->scrubs_running)) {
mutex_unlock(&fs_info->scrub_lock);
return -ENOTCONN;
}
atomic_inc(&fs_info->scrub_cancel_req);
while (atomic_read(&fs_info->scrubs_running)) {
mutex_unlock(&fs_info->scrub_lock);
wait_event(fs_info->scrub_pause_wait,
atomic_read(&fs_info->scrubs_running) == 0);
mutex_lock(&fs_info->scrub_lock);
}
atomic_dec(&fs_info->scrub_cancel_req);
mutex_unlock(&fs_info->scrub_lock);
return 0;
}
int btrfs_scrub_cancel_dev(struct btrfs_root *root, struct btrfs_device *dev)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct scrub_dev *sdev;
mutex_lock(&fs_info->scrub_lock);
sdev = dev->scrub_device;
if (!sdev) {
mutex_unlock(&fs_info->scrub_lock);
return -ENOTCONN;
}
atomic_inc(&sdev->cancel_req);
while (dev->scrub_device) {
mutex_unlock(&fs_info->scrub_lock);
wait_event(fs_info->scrub_pause_wait,
dev->scrub_device == NULL);
mutex_lock(&fs_info->scrub_lock);
}
mutex_unlock(&fs_info->scrub_lock);
return 0;
}
int btrfs_scrub_cancel_devid(struct btrfs_root *root, u64 devid)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_device *dev;
int ret;
/*
* we have to hold the device_list_mutex here so the device
* does not go away in cancel_dev. FIXME: find a better solution
*/
mutex_lock(&fs_info->fs_devices->device_list_mutex);
dev = btrfs_find_device(root, devid, NULL, NULL);
if (!dev) {
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
return -ENODEV;
}
ret = btrfs_scrub_cancel_dev(root, dev);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
return ret;
}
int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
struct btrfs_scrub_progress *progress)
{
struct btrfs_device *dev;
struct scrub_dev *sdev = NULL;
mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
dev = btrfs_find_device(root, devid, NULL, NULL);
if (dev)
sdev = dev->scrub_device;
if (sdev)
memcpy(progress, &sdev->stat, sizeof(*progress));
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
return dev ? (sdev ? 0 : -ENOTCONN) : -ENODEV;
}