blob: 14a8d710001838501623672997ee07b1e956f298 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2011, 2012 STRATO. All rights reserved.
*/
#include <linux/blkdev.h>
#include <linux/ratelimit.h>
#include <linux/sched/mm.h>
#include <crypto/hash.h>
#include "ctree.h"
#include "discard.h"
#include "volumes.h"
#include "disk-io.h"
#include "ordered-data.h"
#include "transaction.h"
#include "backref.h"
#include "extent_io.h"
#include "dev-replace.h"
#include "raid56.h"
#include "block-group.h"
#include "zoned.h"
#include "fs.h"
#include "accessors.h"
#include "file-item.h"
#include "scrub.h"
#include "raid-stripe-tree.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
* - track and record media errors, throw out bad devices
* - add a mode to also read unallocated space
*/
struct scrub_ctx;
/*
* The following value only influences the performance.
*
* This determines how many stripes would be submitted in one go,
* which is 512KiB (BTRFS_STRIPE_LEN * SCRUB_STRIPES_PER_GROUP).
*/
#define SCRUB_STRIPES_PER_GROUP 8
/*
* How many groups we have for each sctx.
*
* This would be 8M per device, the same value as the old scrub in-flight bios
* size limit.
*/
#define SCRUB_GROUPS_PER_SCTX 16
#define SCRUB_TOTAL_STRIPES (SCRUB_GROUPS_PER_SCTX * SCRUB_STRIPES_PER_GROUP)
/*
* The following value times PAGE_SIZE needs to be large enough to match the
* largest node/leaf/sector size that shall be supported.
*/
#define SCRUB_MAX_SECTORS_PER_BLOCK (BTRFS_MAX_METADATA_BLOCKSIZE / SZ_4K)
/* Represent one sector and its needed info to verify the content. */
struct scrub_sector_verification {
bool is_metadata;
union {
/*
* Csum pointer for data csum verification. Should point to a
* sector csum inside scrub_stripe::csums.
*
* NULL if this data sector has no csum.
*/
u8 *csum;
/*
* Extra info for metadata verification. All sectors inside a
* tree block share the same generation.
*/
u64 generation;
};
};
enum scrub_stripe_flags {
/* Set when @mirror_num, @dev, @physical and @logical are set. */
SCRUB_STRIPE_FLAG_INITIALIZED,
/* Set when the read-repair is finished. */
SCRUB_STRIPE_FLAG_REPAIR_DONE,
/*
* Set for data stripes if it's triggered from P/Q stripe.
* During such scrub, we should not report errors in data stripes, nor
* update the accounting.
*/
SCRUB_STRIPE_FLAG_NO_REPORT,
};
#define SCRUB_STRIPE_PAGES (BTRFS_STRIPE_LEN / PAGE_SIZE)
/*
* Represent one contiguous range with a length of BTRFS_STRIPE_LEN.
*/
struct scrub_stripe {
struct scrub_ctx *sctx;
struct btrfs_block_group *bg;
struct page *pages[SCRUB_STRIPE_PAGES];
struct scrub_sector_verification *sectors;
struct btrfs_device *dev;
u64 logical;
u64 physical;
u16 mirror_num;
/* Should be BTRFS_STRIPE_LEN / sectorsize. */
u16 nr_sectors;
/*
* How many data/meta extents are in this stripe. Only for scrub status
* reporting purposes.
*/
u16 nr_data_extents;
u16 nr_meta_extents;
atomic_t pending_io;
wait_queue_head_t io_wait;
wait_queue_head_t repair_wait;
/*
* Indicate the states of the stripe. Bits are defined in
* scrub_stripe_flags enum.
*/
unsigned long state;
/* Indicate which sectors are covered by extent items. */
unsigned long extent_sector_bitmap;
/*
* The errors hit during the initial read of the stripe.
*
* Would be utilized for error reporting and repair.
*
* The remaining init_nr_* records the number of errors hit, only used
* by error reporting.
*/
unsigned long init_error_bitmap;
unsigned int init_nr_io_errors;
unsigned int init_nr_csum_errors;
unsigned int init_nr_meta_errors;
/*
* The following error bitmaps are all for the current status.
* Every time we submit a new read, these bitmaps may be updated.
*
* error_bitmap = io_error_bitmap | csum_error_bitmap | meta_error_bitmap;
*
* IO and csum errors can happen for both metadata and data.
*/
unsigned long error_bitmap;
unsigned long io_error_bitmap;
unsigned long csum_error_bitmap;
unsigned long meta_error_bitmap;
/* For writeback (repair or replace) error reporting. */
unsigned long write_error_bitmap;
/* Writeback can be concurrent, thus we need to protect the bitmap. */
spinlock_t write_error_lock;
/*
* Checksum for the whole stripe if this stripe is inside a data block
* group.
*/
u8 *csums;
struct work_struct work;
};
struct scrub_ctx {
struct scrub_stripe stripes[SCRUB_TOTAL_STRIPES];
struct scrub_stripe *raid56_data_stripes;
struct btrfs_fs_info *fs_info;
struct btrfs_path extent_path;
struct btrfs_path csum_path;
int first_free;
int cur_stripe;
atomic_t cancel_req;
int readonly;
/* State of IO submission throttling affecting the associated device */
ktime_t throttle_deadline;
u64 throttle_sent;
int is_dev_replace;
u64 write_pointer;
struct mutex wr_lock;
struct btrfs_device *wr_tgtdev;
/*
* statistics
*/
struct btrfs_scrub_progress stat;
spinlock_t stat_lock;
/*
* Use a ref counter to avoid use-after-free issues. Scrub workers
* decrement bios_in_flight and workers_pending and then do a wakeup
* on the list_wait wait queue. We must ensure the main scrub task
* doesn't free the scrub context before or while the workers are
* doing the wakeup() call.
*/
refcount_t refs;
};
struct scrub_warning {
struct btrfs_path *path;
u64 extent_item_size;
const char *errstr;
u64 physical;
u64 logical;
struct btrfs_device *dev;
};
static void release_scrub_stripe(struct scrub_stripe *stripe)
{
if (!stripe)
return;
for (int i = 0; i < SCRUB_STRIPE_PAGES; i++) {
if (stripe->pages[i])
__free_page(stripe->pages[i]);
stripe->pages[i] = NULL;
}
kfree(stripe->sectors);
kfree(stripe->csums);
stripe->sectors = NULL;
stripe->csums = NULL;
stripe->sctx = NULL;
stripe->state = 0;
}
static int init_scrub_stripe(struct btrfs_fs_info *fs_info,
struct scrub_stripe *stripe)
{
int ret;
memset(stripe, 0, sizeof(*stripe));
stripe->nr_sectors = BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits;
stripe->state = 0;
init_waitqueue_head(&stripe->io_wait);
init_waitqueue_head(&stripe->repair_wait);
atomic_set(&stripe->pending_io, 0);
spin_lock_init(&stripe->write_error_lock);
ret = btrfs_alloc_page_array(SCRUB_STRIPE_PAGES, stripe->pages, false);
if (ret < 0)
goto error;
stripe->sectors = kcalloc(stripe->nr_sectors,
sizeof(struct scrub_sector_verification),
GFP_KERNEL);
if (!stripe->sectors)
goto error;
stripe->csums = kcalloc(BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits,
fs_info->csum_size, GFP_KERNEL);
if (!stripe->csums)
goto error;
return 0;
error:
release_scrub_stripe(stripe);
return -ENOMEM;
}
static void wait_scrub_stripe_io(struct scrub_stripe *stripe)
{
wait_event(stripe->io_wait, atomic_read(&stripe->pending_io) == 0);
}
static void scrub_put_ctx(struct scrub_ctx *sctx);
static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
{
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);
}
}
static void scrub_pause_on(struct btrfs_fs_info *fs_info)
{
atomic_inc(&fs_info->scrubs_paused);
wake_up(&fs_info->scrub_pause_wait);
}
static void scrub_pause_off(struct btrfs_fs_info *fs_info)
{
mutex_lock(&fs_info->scrub_lock);
__scrub_blocked_if_needed(fs_info);
atomic_dec(&fs_info->scrubs_paused);
mutex_unlock(&fs_info->scrub_lock);
wake_up(&fs_info->scrub_pause_wait);
}
static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
{
scrub_pause_on(fs_info);
scrub_pause_off(fs_info);
}
static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx)
{
int i;
if (!sctx)
return;
for (i = 0; i < SCRUB_TOTAL_STRIPES; i++)
release_scrub_stripe(&sctx->stripes[i]);
kvfree(sctx);
}
static void scrub_put_ctx(struct scrub_ctx *sctx)
{
if (refcount_dec_and_test(&sctx->refs))
scrub_free_ctx(sctx);
}
static noinline_for_stack struct scrub_ctx *scrub_setup_ctx(
struct btrfs_fs_info *fs_info, int is_dev_replace)
{
struct scrub_ctx *sctx;
int i;
/* Since sctx has inline 128 stripes, it can go beyond 64K easily. Use
* kvzalloc().
*/
sctx = kvzalloc(sizeof(*sctx), GFP_KERNEL);
if (!sctx)
goto nomem;
refcount_set(&sctx->refs, 1);
sctx->is_dev_replace = is_dev_replace;
sctx->fs_info = fs_info;
sctx->extent_path.search_commit_root = 1;
sctx->extent_path.skip_locking = 1;
sctx->csum_path.search_commit_root = 1;
sctx->csum_path.skip_locking = 1;
for (i = 0; i < SCRUB_TOTAL_STRIPES; i++) {
int ret;
ret = init_scrub_stripe(fs_info, &sctx->stripes[i]);
if (ret < 0)
goto nomem;
sctx->stripes[i].sctx = sctx;
}
sctx->first_free = 0;
atomic_set(&sctx->cancel_req, 0);
spin_lock_init(&sctx->stat_lock);
sctx->throttle_deadline = 0;
mutex_init(&sctx->wr_lock);
if (is_dev_replace) {
WARN_ON(!fs_info->dev_replace.tgtdev);
sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
}
return sctx;
nomem:
scrub_free_ctx(sctx);
return ERR_PTR(-ENOMEM);
}
static int scrub_print_warning_inode(u64 inum, u64 offset, u64 num_bytes,
u64 root, void *warn_ctx)
{
u32 nlink;
int ret;
int i;
unsigned nofs_flag;
struct extent_buffer *eb;
struct btrfs_inode_item *inode_item;
struct scrub_warning *swarn = warn_ctx;
struct btrfs_fs_info *fs_info = swarn->dev->fs_info;
struct inode_fs_paths *ipath = NULL;
struct btrfs_root *local_root;
struct btrfs_key key;
local_root = btrfs_get_fs_root(fs_info, root, true);
if (IS_ERR(local_root)) {
ret = PTR_ERR(local_root);
goto err;
}
/*
* this makes the path point to (inum INODE_ITEM ioff)
*/
key.objectid = inum;
key.type = BTRFS_INODE_ITEM_KEY;
key.offset = 0;
ret = btrfs_search_slot(NULL, local_root, &key, swarn->path, 0, 0);
if (ret) {
btrfs_put_root(local_root);
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);
nlink = btrfs_inode_nlink(eb, inode_item);
btrfs_release_path(swarn->path);
/*
* init_path might indirectly call vmalloc, or use GFP_KERNEL. Scrub
* uses GFP_NOFS in this context, so we keep it consistent but it does
* not seem to be strictly necessary.
*/
nofs_flag = memalloc_nofs_save();
ipath = init_ipath(4096, local_root, swarn->path);
memalloc_nofs_restore(nofs_flag);
if (IS_ERR(ipath)) {
btrfs_put_root(local_root);
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)
btrfs_warn_in_rcu(fs_info,
"%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu, length %u, links %u (path: %s)",
swarn->errstr, swarn->logical,
btrfs_dev_name(swarn->dev),
swarn->physical,
root, inum, offset,
fs_info->sectorsize, nlink,
(char *)(unsigned long)ipath->fspath->val[i]);
btrfs_put_root(local_root);
free_ipath(ipath);
return 0;
err:
btrfs_warn_in_rcu(fs_info,
"%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu: path resolving failed with ret=%d",
swarn->errstr, swarn->logical,
btrfs_dev_name(swarn->dev),
swarn->physical,
root, inum, offset, ret);
free_ipath(ipath);
return 0;
}
static void scrub_print_common_warning(const char *errstr, struct btrfs_device *dev,
bool is_super, u64 logical, u64 physical)
{
struct btrfs_fs_info *fs_info = dev->fs_info;
struct btrfs_path *path;
struct btrfs_key found_key;
struct extent_buffer *eb;
struct btrfs_extent_item *ei;
struct scrub_warning swarn;
u64 flags = 0;
u32 item_size;
int ret;
/* Super block error, no need to search extent tree. */
if (is_super) {
btrfs_warn_in_rcu(fs_info, "%s on device %s, physical %llu",
errstr, btrfs_dev_name(dev), physical);
return;
}
path = btrfs_alloc_path();
if (!path)
return;
swarn.physical = physical;
swarn.logical = logical;
swarn.errstr = errstr;
swarn.dev = NULL;
ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,
&flags);
if (ret < 0)
goto out;
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(eb, path->slots[0]);
if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
unsigned long ptr = 0;
u8 ref_level;
u64 ref_root;
while (true) {
ret = tree_backref_for_extent(&ptr, eb, &found_key, ei,
item_size, &ref_root,
&ref_level);
if (ret < 0) {
btrfs_warn(fs_info,
"failed to resolve tree backref for logical %llu: %d",
swarn.logical, ret);
break;
}
if (ret > 0)
break;
btrfs_warn_in_rcu(fs_info,
"%s at logical %llu on dev %s, physical %llu: metadata %s (level %d) in tree %llu",
errstr, swarn.logical, btrfs_dev_name(dev),
swarn.physical, (ref_level ? "node" : "leaf"),
ref_level, ref_root);
}
btrfs_release_path(path);
} else {
struct btrfs_backref_walk_ctx ctx = { 0 };
btrfs_release_path(path);
ctx.bytenr = found_key.objectid;
ctx.extent_item_pos = swarn.logical - found_key.objectid;
ctx.fs_info = fs_info;
swarn.path = path;
swarn.dev = dev;
iterate_extent_inodes(&ctx, true, scrub_print_warning_inode, &swarn);
}
out:
btrfs_free_path(path);
}
static int fill_writer_pointer_gap(struct scrub_ctx *sctx, u64 physical)
{
int ret = 0;
u64 length;
if (!btrfs_is_zoned(sctx->fs_info))
return 0;
if (!btrfs_dev_is_sequential(sctx->wr_tgtdev, physical))
return 0;
if (sctx->write_pointer < physical) {
length = physical - sctx->write_pointer;
ret = btrfs_zoned_issue_zeroout(sctx->wr_tgtdev,
sctx->write_pointer, length);
if (!ret)
sctx->write_pointer = physical;
}
return ret;
}
static struct page *scrub_stripe_get_page(struct scrub_stripe *stripe, int sector_nr)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
int page_index = (sector_nr << fs_info->sectorsize_bits) >> PAGE_SHIFT;
return stripe->pages[page_index];
}
static unsigned int scrub_stripe_get_page_offset(struct scrub_stripe *stripe,
int sector_nr)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
return offset_in_page(sector_nr << fs_info->sectorsize_bits);
}
static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits;
const u64 logical = stripe->logical + (sector_nr << fs_info->sectorsize_bits);
const struct page *first_page = scrub_stripe_get_page(stripe, sector_nr);
const unsigned int first_off = scrub_stripe_get_page_offset(stripe, sector_nr);
SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
u8 on_disk_csum[BTRFS_CSUM_SIZE];
u8 calculated_csum[BTRFS_CSUM_SIZE];
struct btrfs_header *header;
/*
* Here we don't have a good way to attach the pages (and subpages)
* to a dummy extent buffer, thus we have to directly grab the members
* from pages.
*/
header = (struct btrfs_header *)(page_address(first_page) + first_off);
memcpy(on_disk_csum, header->csum, fs_info->csum_size);
if (logical != btrfs_stack_header_bytenr(header)) {
bitmap_set(&stripe->csum_error_bitmap, sector_nr, sectors_per_tree);
bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree);
btrfs_warn_rl(fs_info,
"tree block %llu mirror %u has bad bytenr, has %llu want %llu",
logical, stripe->mirror_num,
btrfs_stack_header_bytenr(header), logical);
return;
}
if (memcmp(header->fsid, fs_info->fs_devices->metadata_uuid,
BTRFS_FSID_SIZE) != 0) {
bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree);
bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree);
btrfs_warn_rl(fs_info,
"tree block %llu mirror %u has bad fsid, has %pU want %pU",
logical, stripe->mirror_num,
header->fsid, fs_info->fs_devices->fsid);
return;
}
if (memcmp(header->chunk_tree_uuid, fs_info->chunk_tree_uuid,
BTRFS_UUID_SIZE) != 0) {
bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree);
bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree);
btrfs_warn_rl(fs_info,
"tree block %llu mirror %u has bad chunk tree uuid, has %pU want %pU",
logical, stripe->mirror_num,
header->chunk_tree_uuid, fs_info->chunk_tree_uuid);
return;
}
/* Now check tree block csum. */
shash->tfm = fs_info->csum_shash;
crypto_shash_init(shash);
crypto_shash_update(shash, page_address(first_page) + first_off +
BTRFS_CSUM_SIZE, fs_info->sectorsize - BTRFS_CSUM_SIZE);
for (int i = sector_nr + 1; i < sector_nr + sectors_per_tree; i++) {
struct page *page = scrub_stripe_get_page(stripe, i);
unsigned int page_off = scrub_stripe_get_page_offset(stripe, i);
crypto_shash_update(shash, page_address(page) + page_off,
fs_info->sectorsize);
}
crypto_shash_final(shash, calculated_csum);
if (memcmp(calculated_csum, on_disk_csum, fs_info->csum_size) != 0) {
bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree);
bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree);
btrfs_warn_rl(fs_info,
"tree block %llu mirror %u has bad csum, has " CSUM_FMT " want " CSUM_FMT,
logical, stripe->mirror_num,
CSUM_FMT_VALUE(fs_info->csum_size, on_disk_csum),
CSUM_FMT_VALUE(fs_info->csum_size, calculated_csum));
return;
}
if (stripe->sectors[sector_nr].generation !=
btrfs_stack_header_generation(header)) {
bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree);
bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree);
btrfs_warn_rl(fs_info,
"tree block %llu mirror %u has bad generation, has %llu want %llu",
logical, stripe->mirror_num,
btrfs_stack_header_generation(header),
stripe->sectors[sector_nr].generation);
return;
}
bitmap_clear(&stripe->error_bitmap, sector_nr, sectors_per_tree);
bitmap_clear(&stripe->csum_error_bitmap, sector_nr, sectors_per_tree);
bitmap_clear(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree);
}
static void scrub_verify_one_sector(struct scrub_stripe *stripe, int sector_nr)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
struct scrub_sector_verification *sector = &stripe->sectors[sector_nr];
const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits;
struct page *page = scrub_stripe_get_page(stripe, sector_nr);
unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr);
u8 csum_buf[BTRFS_CSUM_SIZE];
int ret;
ASSERT(sector_nr >= 0 && sector_nr < stripe->nr_sectors);
/* Sector not utilized, skip it. */
if (!test_bit(sector_nr, &stripe->extent_sector_bitmap))
return;
/* IO error, no need to check. */
if (test_bit(sector_nr, &stripe->io_error_bitmap))
return;
/* Metadata, verify the full tree block. */
if (sector->is_metadata) {
/*
* Check if the tree block crosses the stripe boundary. If
* crossed the boundary, we cannot verify it but only give a
* warning.
*
* This can only happen on a very old filesystem where chunks
* are not ensured to be stripe aligned.
*/
if (unlikely(sector_nr + sectors_per_tree > stripe->nr_sectors)) {
btrfs_warn_rl(fs_info,
"tree block at %llu crosses stripe boundary %llu",
stripe->logical +
(sector_nr << fs_info->sectorsize_bits),
stripe->logical);
return;
}
scrub_verify_one_metadata(stripe, sector_nr);
return;
}
/*
* Data is easier, we just verify the data csum (if we have it). For
* cases without csum, we have no other choice but to trust it.
*/
if (!sector->csum) {
clear_bit(sector_nr, &stripe->error_bitmap);
return;
}
ret = btrfs_check_sector_csum(fs_info, page, pgoff, csum_buf, sector->csum);
if (ret < 0) {
set_bit(sector_nr, &stripe->csum_error_bitmap);
set_bit(sector_nr, &stripe->error_bitmap);
} else {
clear_bit(sector_nr, &stripe->csum_error_bitmap);
clear_bit(sector_nr, &stripe->error_bitmap);
}
}
/* Verify specified sectors of a stripe. */
static void scrub_verify_one_stripe(struct scrub_stripe *stripe, unsigned long bitmap)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits;
int sector_nr;
for_each_set_bit(sector_nr, &bitmap, stripe->nr_sectors) {
scrub_verify_one_sector(stripe, sector_nr);
if (stripe->sectors[sector_nr].is_metadata)
sector_nr += sectors_per_tree - 1;
}
}
static int calc_sector_number(struct scrub_stripe *stripe, struct bio_vec *first_bvec)
{
int i;
for (i = 0; i < stripe->nr_sectors; i++) {
if (scrub_stripe_get_page(stripe, i) == first_bvec->bv_page &&
scrub_stripe_get_page_offset(stripe, i) == first_bvec->bv_offset)
break;
}
ASSERT(i < stripe->nr_sectors);
return i;
}
/*
* Repair read is different to the regular read:
*
* - Only reads the failed sectors
* - May have extra blocksize limits
*/
static void scrub_repair_read_endio(struct btrfs_bio *bbio)
{
struct scrub_stripe *stripe = bbio->private;
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
struct bio_vec *bvec;
int sector_nr = calc_sector_number(stripe, bio_first_bvec_all(&bbio->bio));
u32 bio_size = 0;
int i;
ASSERT(sector_nr < stripe->nr_sectors);
bio_for_each_bvec_all(bvec, &bbio->bio, i)
bio_size += bvec->bv_len;
if (bbio->bio.bi_status) {
bitmap_set(&stripe->io_error_bitmap, sector_nr,
bio_size >> fs_info->sectorsize_bits);
bitmap_set(&stripe->error_bitmap, sector_nr,
bio_size >> fs_info->sectorsize_bits);
} else {
bitmap_clear(&stripe->io_error_bitmap, sector_nr,
bio_size >> fs_info->sectorsize_bits);
}
bio_put(&bbio->bio);
if (atomic_dec_and_test(&stripe->pending_io))
wake_up(&stripe->io_wait);
}
static int calc_next_mirror(int mirror, int num_copies)
{
ASSERT(mirror <= num_copies);
return (mirror + 1 > num_copies) ? 1 : mirror + 1;
}
static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe,
int mirror, int blocksize, bool wait)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
struct btrfs_bio *bbio = NULL;
const unsigned long old_error_bitmap = stripe->error_bitmap;
int i;
ASSERT(stripe->mirror_num >= 1);
ASSERT(atomic_read(&stripe->pending_io) == 0);
for_each_set_bit(i, &old_error_bitmap, stripe->nr_sectors) {
struct page *page;
int pgoff;
int ret;
page = scrub_stripe_get_page(stripe, i);
pgoff = scrub_stripe_get_page_offset(stripe, i);
/* The current sector cannot be merged, submit the bio. */
if (bbio && ((i > 0 && !test_bit(i - 1, &stripe->error_bitmap)) ||
bbio->bio.bi_iter.bi_size >= blocksize)) {
ASSERT(bbio->bio.bi_iter.bi_size);
atomic_inc(&stripe->pending_io);
btrfs_submit_bio(bbio, mirror);
if (wait)
wait_scrub_stripe_io(stripe);
bbio = NULL;
}
if (!bbio) {
bbio = btrfs_bio_alloc(stripe->nr_sectors, REQ_OP_READ,
fs_info, scrub_repair_read_endio, stripe);
bbio->bio.bi_iter.bi_sector = (stripe->logical +
(i << fs_info->sectorsize_bits)) >> SECTOR_SHIFT;
}
ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff);
ASSERT(ret == fs_info->sectorsize);
}
if (bbio) {
ASSERT(bbio->bio.bi_iter.bi_size);
atomic_inc(&stripe->pending_io);
btrfs_submit_bio(bbio, mirror);
if (wait)
wait_scrub_stripe_io(stripe);
}
}
static void scrub_stripe_report_errors(struct scrub_ctx *sctx,
struct scrub_stripe *stripe)
{
static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
struct btrfs_fs_info *fs_info = sctx->fs_info;
struct btrfs_device *dev = NULL;
u64 physical = 0;
int nr_data_sectors = 0;
int nr_meta_sectors = 0;
int nr_nodatacsum_sectors = 0;
int nr_repaired_sectors = 0;
int sector_nr;
if (test_bit(SCRUB_STRIPE_FLAG_NO_REPORT, &stripe->state))
return;
/*
* Init needed infos for error reporting.
*
* Although our scrub_stripe infrastructure is mostly based on btrfs_submit_bio()
* thus no need for dev/physical, error reporting still needs dev and physical.
*/
if (!bitmap_empty(&stripe->init_error_bitmap, stripe->nr_sectors)) {
u64 mapped_len = fs_info->sectorsize;
struct btrfs_io_context *bioc = NULL;
int stripe_index = stripe->mirror_num - 1;
int ret;
/* For scrub, our mirror_num should always start at 1. */
ASSERT(stripe->mirror_num >= 1);
ret = btrfs_map_block(fs_info, BTRFS_MAP_GET_READ_MIRRORS,
stripe->logical, &mapped_len, &bioc,
NULL, NULL);
/*
* If we failed, dev will be NULL, and later detailed reports
* will just be skipped.
*/
if (ret < 0)
goto skip;
physical = bioc->stripes[stripe_index].physical;
dev = bioc->stripes[stripe_index].dev;
btrfs_put_bioc(bioc);
}
skip:
for_each_set_bit(sector_nr, &stripe->extent_sector_bitmap, stripe->nr_sectors) {
bool repaired = false;
if (stripe->sectors[sector_nr].is_metadata) {
nr_meta_sectors++;
} else {
nr_data_sectors++;
if (!stripe->sectors[sector_nr].csum)
nr_nodatacsum_sectors++;
}
if (test_bit(sector_nr, &stripe->init_error_bitmap) &&
!test_bit(sector_nr, &stripe->error_bitmap)) {
nr_repaired_sectors++;
repaired = true;
}
/* Good sector from the beginning, nothing need to be done. */
if (!test_bit(sector_nr, &stripe->init_error_bitmap))
continue;
/*
* Report error for the corrupted sectors. If repaired, just
* output the message of repaired message.
*/
if (repaired) {
if (dev) {
btrfs_err_rl_in_rcu(fs_info,
"fixed up error at logical %llu on dev %s physical %llu",
stripe->logical, btrfs_dev_name(dev),
physical);
} else {
btrfs_err_rl_in_rcu(fs_info,
"fixed up error at logical %llu on mirror %u",
stripe->logical, stripe->mirror_num);
}
continue;
}
/* The remaining are all for unrepaired. */
if (dev) {
btrfs_err_rl_in_rcu(fs_info,
"unable to fixup (regular) error at logical %llu on dev %s physical %llu",
stripe->logical, btrfs_dev_name(dev),
physical);
} else {
btrfs_err_rl_in_rcu(fs_info,
"unable to fixup (regular) error at logical %llu on mirror %u",
stripe->logical, stripe->mirror_num);
}
if (test_bit(sector_nr, &stripe->io_error_bitmap))
if (__ratelimit(&rs) && dev)
scrub_print_common_warning("i/o error", dev, false,
stripe->logical, physical);
if (test_bit(sector_nr, &stripe->csum_error_bitmap))
if (__ratelimit(&rs) && dev)
scrub_print_common_warning("checksum error", dev, false,
stripe->logical, physical);
if (test_bit(sector_nr, &stripe->meta_error_bitmap))
if (__ratelimit(&rs) && dev)
scrub_print_common_warning("header error", dev, false,
stripe->logical, physical);
}
spin_lock(&sctx->stat_lock);
sctx->stat.data_extents_scrubbed += stripe->nr_data_extents;
sctx->stat.tree_extents_scrubbed += stripe->nr_meta_extents;
sctx->stat.data_bytes_scrubbed += nr_data_sectors << fs_info->sectorsize_bits;
sctx->stat.tree_bytes_scrubbed += nr_meta_sectors << fs_info->sectorsize_bits;
sctx->stat.no_csum += nr_nodatacsum_sectors;
sctx->stat.read_errors += stripe->init_nr_io_errors;
sctx->stat.csum_errors += stripe->init_nr_csum_errors;
sctx->stat.verify_errors += stripe->init_nr_meta_errors;
sctx->stat.uncorrectable_errors +=
bitmap_weight(&stripe->error_bitmap, stripe->nr_sectors);
sctx->stat.corrected_errors += nr_repaired_sectors;
spin_unlock(&sctx->stat_lock);
}
static void scrub_write_sectors(struct scrub_ctx *sctx, struct scrub_stripe *stripe,
unsigned long write_bitmap, bool dev_replace);
/*
* The main entrance for all read related scrub work, including:
*
* - Wait for the initial read to finish
* - Verify and locate any bad sectors
* - Go through the remaining mirrors and try to read as large blocksize as
* possible
* - Go through all mirrors (including the failed mirror) sector-by-sector
* - Submit writeback for repaired sectors
*
* Writeback for dev-replace does not happen here, it needs extra
* synchronization for zoned devices.
*/
static void scrub_stripe_read_repair_worker(struct work_struct *work)
{
struct scrub_stripe *stripe = container_of(work, struct scrub_stripe, work);
struct scrub_ctx *sctx = stripe->sctx;
struct btrfs_fs_info *fs_info = sctx->fs_info;
int num_copies = btrfs_num_copies(fs_info, stripe->bg->start,
stripe->bg->length);
unsigned long repaired;
int mirror;
int i;
ASSERT(stripe->mirror_num > 0);
wait_scrub_stripe_io(stripe);
scrub_verify_one_stripe(stripe, stripe->extent_sector_bitmap);
/* Save the initial failed bitmap for later repair and report usage. */
stripe->init_error_bitmap = stripe->error_bitmap;
stripe->init_nr_io_errors = bitmap_weight(&stripe->io_error_bitmap,
stripe->nr_sectors);
stripe->init_nr_csum_errors = bitmap_weight(&stripe->csum_error_bitmap,
stripe->nr_sectors);
stripe->init_nr_meta_errors = bitmap_weight(&stripe->meta_error_bitmap,
stripe->nr_sectors);
if (bitmap_empty(&stripe->init_error_bitmap, stripe->nr_sectors))
goto out;
/*
* Try all remaining mirrors.
*
* Here we still try to read as large block as possible, as this is
* faster and we have extra safety nets to rely on.
*/
for (mirror = calc_next_mirror(stripe->mirror_num, num_copies);
mirror != stripe->mirror_num;
mirror = calc_next_mirror(mirror, num_copies)) {
const unsigned long old_error_bitmap = stripe->error_bitmap;
scrub_stripe_submit_repair_read(stripe, mirror,
BTRFS_STRIPE_LEN, false);
wait_scrub_stripe_io(stripe);
scrub_verify_one_stripe(stripe, old_error_bitmap);
if (bitmap_empty(&stripe->error_bitmap, stripe->nr_sectors))
goto out;
}
/*
* Last safety net, try re-checking all mirrors, including the failed
* one, sector-by-sector.
*
* As if one sector failed the drive's internal csum, the whole read
* containing the offending sector would be marked as error.
* Thus here we do sector-by-sector read.
*
* This can be slow, thus we only try it as the last resort.
*/
for (i = 0, mirror = stripe->mirror_num;
i < num_copies;
i++, mirror = calc_next_mirror(mirror, num_copies)) {
const unsigned long old_error_bitmap = stripe->error_bitmap;
scrub_stripe_submit_repair_read(stripe, mirror,
fs_info->sectorsize, true);
wait_scrub_stripe_io(stripe);
scrub_verify_one_stripe(stripe, old_error_bitmap);
if (bitmap_empty(&stripe->error_bitmap, stripe->nr_sectors))
goto out;
}
out:
/*
* Submit the repaired sectors. For zoned case, we cannot do repair
* in-place, but queue the bg to be relocated.
*/
bitmap_andnot(&repaired, &stripe->init_error_bitmap, &stripe->error_bitmap,
stripe->nr_sectors);
if (!sctx->readonly && !bitmap_empty(&repaired, stripe->nr_sectors)) {
if (btrfs_is_zoned(fs_info)) {
btrfs_repair_one_zone(fs_info, sctx->stripes[0].bg->start);
} else {
scrub_write_sectors(sctx, stripe, repaired, false);
wait_scrub_stripe_io(stripe);
}
}
scrub_stripe_report_errors(sctx, stripe);
set_bit(SCRUB_STRIPE_FLAG_REPAIR_DONE, &stripe->state);
wake_up(&stripe->repair_wait);
}
static void scrub_read_endio(struct btrfs_bio *bbio)
{
struct scrub_stripe *stripe = bbio->private;
struct bio_vec *bvec;
int sector_nr = calc_sector_number(stripe, bio_first_bvec_all(&bbio->bio));
int num_sectors;
u32 bio_size = 0;
int i;
ASSERT(sector_nr < stripe->nr_sectors);
bio_for_each_bvec_all(bvec, &bbio->bio, i)
bio_size += bvec->bv_len;
num_sectors = bio_size >> stripe->bg->fs_info->sectorsize_bits;
if (bbio->bio.bi_status) {
bitmap_set(&stripe->io_error_bitmap, sector_nr, num_sectors);
bitmap_set(&stripe->error_bitmap, sector_nr, num_sectors);
} else {
bitmap_clear(&stripe->io_error_bitmap, sector_nr, num_sectors);
}
bio_put(&bbio->bio);
if (atomic_dec_and_test(&stripe->pending_io)) {
wake_up(&stripe->io_wait);
INIT_WORK(&stripe->work, scrub_stripe_read_repair_worker);
queue_work(stripe->bg->fs_info->scrub_workers, &stripe->work);
}
}
static void scrub_write_endio(struct btrfs_bio *bbio)
{
struct scrub_stripe *stripe = bbio->private;
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
struct bio_vec *bvec;
int sector_nr = calc_sector_number(stripe, bio_first_bvec_all(&bbio->bio));
u32 bio_size = 0;
int i;
bio_for_each_bvec_all(bvec, &bbio->bio, i)
bio_size += bvec->bv_len;
if (bbio->bio.bi_status) {
unsigned long flags;
spin_lock_irqsave(&stripe->write_error_lock, flags);
bitmap_set(&stripe->write_error_bitmap, sector_nr,
bio_size >> fs_info->sectorsize_bits);
spin_unlock_irqrestore(&stripe->write_error_lock, flags);
}
bio_put(&bbio->bio);
if (atomic_dec_and_test(&stripe->pending_io))
wake_up(&stripe->io_wait);
}
static void scrub_submit_write_bio(struct scrub_ctx *sctx,
struct scrub_stripe *stripe,
struct btrfs_bio *bbio, bool dev_replace)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
u32 bio_len = bbio->bio.bi_iter.bi_size;
u32 bio_off = (bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT) -
stripe->logical;
fill_writer_pointer_gap(sctx, stripe->physical + bio_off);
atomic_inc(&stripe->pending_io);
btrfs_submit_repair_write(bbio, stripe->mirror_num, dev_replace);
if (!btrfs_is_zoned(fs_info))
return;
/*
* For zoned writeback, queue depth must be 1, thus we must wait for
* the write to finish before the next write.
*/
wait_scrub_stripe_io(stripe);
/*
* And also need to update the write pointer if write finished
* successfully.
*/
if (!test_bit(bio_off >> fs_info->sectorsize_bits,
&stripe->write_error_bitmap))
sctx->write_pointer += bio_len;
}
/*
* Submit the write bio(s) for the sectors specified by @write_bitmap.
*
* Here we utilize btrfs_submit_repair_write(), which has some extra benefits:
*
* - Only needs logical bytenr and mirror_num
* Just like the scrub read path
*
* - Would only result in writes to the specified mirror
* Unlike the regular writeback path, which would write back to all stripes
*
* - Handle dev-replace and read-repair writeback differently
*/
static void scrub_write_sectors(struct scrub_ctx *sctx, struct scrub_stripe *stripe,
unsigned long write_bitmap, bool dev_replace)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
struct btrfs_bio *bbio = NULL;
int sector_nr;
for_each_set_bit(sector_nr, &write_bitmap, stripe->nr_sectors) {
struct page *page = scrub_stripe_get_page(stripe, sector_nr);
unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr);
int ret;
/* We should only writeback sectors covered by an extent. */
ASSERT(test_bit(sector_nr, &stripe->extent_sector_bitmap));
/* Cannot merge with previous sector, submit the current one. */
if (bbio && sector_nr && !test_bit(sector_nr - 1, &write_bitmap)) {
scrub_submit_write_bio(sctx, stripe, bbio, dev_replace);
bbio = NULL;
}
if (!bbio) {
bbio = btrfs_bio_alloc(stripe->nr_sectors, REQ_OP_WRITE,
fs_info, scrub_write_endio, stripe);
bbio->bio.bi_iter.bi_sector = (stripe->logical +
(sector_nr << fs_info->sectorsize_bits)) >>
SECTOR_SHIFT;
}
ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff);
ASSERT(ret == fs_info->sectorsize);
}
if (bbio)
scrub_submit_write_bio(sctx, stripe, bbio, dev_replace);
}
/*
* Throttling of IO submission, bandwidth-limit based, the timeslice is 1
* second. Limit can be set via /sys/fs/UUID/devinfo/devid/scrub_speed_max.
*/
static void scrub_throttle_dev_io(struct scrub_ctx *sctx, struct btrfs_device *device,
unsigned int bio_size)
{
const int time_slice = 1000;
s64 delta;
ktime_t now;
u32 div;
u64 bwlimit;
bwlimit = READ_ONCE(device->scrub_speed_max);
if (bwlimit == 0)
return;
/*
* Slice is divided into intervals when the IO is submitted, adjust by
* bwlimit and maximum of 64 intervals.
*/
div = max_t(u32, 1, (u32)(bwlimit / (16 * 1024 * 1024)));
div = min_t(u32, 64, div);
/* Start new epoch, set deadline */
now = ktime_get();
if (sctx->throttle_deadline == 0) {
sctx->throttle_deadline = ktime_add_ms(now, time_slice / div);
sctx->throttle_sent = 0;
}
/* Still in the time to send? */
if (ktime_before(now, sctx->throttle_deadline)) {
/* If current bio is within the limit, send it */
sctx->throttle_sent += bio_size;
if (sctx->throttle_sent <= div_u64(bwlimit, div))
return;
/* We're over the limit, sleep until the rest of the slice */
delta = ktime_ms_delta(sctx->throttle_deadline, now);
} else {
/* New request after deadline, start new epoch */
delta = 0;
}
if (delta) {
long timeout;
timeout = div_u64(delta * HZ, 1000);
schedule_timeout_interruptible(timeout);
}
/* Next call will start the deadline period */
sctx->throttle_deadline = 0;
}
/*
* Given a physical address, this will calculate it's
* logical offset. if this is a parity stripe, it will return
* the most left data stripe's logical offset.
*
* return 0 if it is a data stripe, 1 means parity stripe.
*/
static int get_raid56_logic_offset(u64 physical, int num,
struct btrfs_chunk_map *map, u64 *offset,
u64 *stripe_start)
{
int i;
int j = 0;
u64 last_offset;
const int data_stripes = nr_data_stripes(map);
last_offset = (physical - map->stripes[num].physical) * data_stripes;
if (stripe_start)
*stripe_start = last_offset;
*offset = last_offset;
for (i = 0; i < data_stripes; i++) {
u32 stripe_nr;
u32 stripe_index;
u32 rot;
*offset = last_offset + btrfs_stripe_nr_to_offset(i);
stripe_nr = (u32)(*offset >> BTRFS_STRIPE_LEN_SHIFT) / data_stripes;
/* Work out the disk rotation on this stripe-set */
rot = stripe_nr % map->num_stripes;
/* calculate which stripe this data locates */
rot += i;
stripe_index = rot % map->num_stripes;
if (stripe_index == num)
return 0;
if (stripe_index < num)
j++;
}
*offset = last_offset + btrfs_stripe_nr_to_offset(j);
return 1;
}
/*
* Return 0 if the extent item range covers any byte of the range.
* Return <0 if the extent item is before @search_start.
* Return >0 if the extent item is after @start_start + @search_len.
*/
static int compare_extent_item_range(struct btrfs_path *path,
u64 search_start, u64 search_len)
{
struct btrfs_fs_info *fs_info = path->nodes[0]->fs_info;
u64 len;
struct btrfs_key key;
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
ASSERT(key.type == BTRFS_EXTENT_ITEM_KEY ||
key.type == BTRFS_METADATA_ITEM_KEY);
if (key.type == BTRFS_METADATA_ITEM_KEY)
len = fs_info->nodesize;
else
len = key.offset;
if (key.objectid + len <= search_start)
return -1;
if (key.objectid >= search_start + search_len)
return 1;
return 0;
}
/*
* Locate one extent item which covers any byte in range
* [@search_start, @search_start + @search_length)
*
* If the path is not initialized, we will initialize the search by doing
* a btrfs_search_slot().
* If the path is already initialized, we will use the path as the initial
* slot, to avoid duplicated btrfs_search_slot() calls.
*
* NOTE: If an extent item starts before @search_start, we will still
* return the extent item. This is for data extent crossing stripe boundary.
*
* Return 0 if we found such extent item, and @path will point to the extent item.
* Return >0 if no such extent item can be found, and @path will be released.
* Return <0 if hit fatal error, and @path will be released.
*/
static int find_first_extent_item(struct btrfs_root *extent_root,
struct btrfs_path *path,
u64 search_start, u64 search_len)
{
struct btrfs_fs_info *fs_info = extent_root->fs_info;
struct btrfs_key key;
int ret;
/* Continue using the existing path */
if (path->nodes[0])
goto search_forward;
if (btrfs_fs_incompat(fs_info, SKINNY_METADATA))
key.type = BTRFS_METADATA_ITEM_KEY;
else
key.type = BTRFS_EXTENT_ITEM_KEY;
key.objectid = search_start;
key.offset = (u64)-1;
ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
if (ret < 0)
return ret;
if (ret == 0) {
/*
* Key with offset -1 found, there would have to exist an extent
* item with such offset, but this is out of the valid range.
*/
btrfs_release_path(path);
return -EUCLEAN;
}
/*
* Here we intentionally pass 0 as @min_objectid, as there could be
* an extent item starting before @search_start.
*/
ret = btrfs_previous_extent_item(extent_root, path, 0);
if (ret < 0)
return ret;
/*
* No matter whether we have found an extent item, the next loop will
* properly do every check on the key.
*/
search_forward:
while (true) {
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
if (key.objectid >= search_start + search_len)
break;
if (key.type != BTRFS_METADATA_ITEM_KEY &&
key.type != BTRFS_EXTENT_ITEM_KEY)
goto next;
ret = compare_extent_item_range(path, search_start, search_len);
if (ret == 0)
return ret;
if (ret > 0)
break;
next:
ret = btrfs_next_item(extent_root, path);
if (ret) {
/* Either no more items or a fatal error. */
btrfs_release_path(path);
return ret;
}
}
btrfs_release_path(path);
return 1;
}
static void get_extent_info(struct btrfs_path *path, u64 *extent_start_ret,
u64 *size_ret, u64 *flags_ret, u64 *generation_ret)
{
struct btrfs_key key;
struct btrfs_extent_item *ei;
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
ASSERT(key.type == BTRFS_METADATA_ITEM_KEY ||
key.type == BTRFS_EXTENT_ITEM_KEY);
*extent_start_ret = key.objectid;
if (key.type == BTRFS_METADATA_ITEM_KEY)
*size_ret = path->nodes[0]->fs_info->nodesize;
else
*size_ret = key.offset;
ei = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_extent_item);
*flags_ret = btrfs_extent_flags(path->nodes[0], ei);
*generation_ret = btrfs_extent_generation(path->nodes[0], ei);
}
static int sync_write_pointer_for_zoned(struct scrub_ctx *sctx, u64 logical,
u64 physical, u64 physical_end)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
int ret = 0;
if (!btrfs_is_zoned(fs_info))
return 0;
mutex_lock(&sctx->wr_lock);
if (sctx->write_pointer < physical_end) {
ret = btrfs_sync_zone_write_pointer(sctx->wr_tgtdev, logical,
physical,
sctx->write_pointer);
if (ret)
btrfs_err(fs_info,
"zoned: failed to recover write pointer");
}
mutex_unlock(&sctx->wr_lock);
btrfs_dev_clear_zone_empty(sctx->wr_tgtdev, physical);
return ret;
}
static void fill_one_extent_info(struct btrfs_fs_info *fs_info,
struct scrub_stripe *stripe,
u64 extent_start, u64 extent_len,
u64 extent_flags, u64 extent_gen)
{
for (u64 cur_logical = max(stripe->logical, extent_start);
cur_logical < min(stripe->logical + BTRFS_STRIPE_LEN,
extent_start + extent_len);
cur_logical += fs_info->sectorsize) {
const int nr_sector = (cur_logical - stripe->logical) >>
fs_info->sectorsize_bits;
struct scrub_sector_verification *sector =
&stripe->sectors[nr_sector];
set_bit(nr_sector, &stripe->extent_sector_bitmap);
if (extent_flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
sector->is_metadata = true;
sector->generation = extent_gen;
}
}
}
static void scrub_stripe_reset_bitmaps(struct scrub_stripe *stripe)
{
stripe->extent_sector_bitmap = 0;
stripe->init_error_bitmap = 0;
stripe->init_nr_io_errors = 0;
stripe->init_nr_csum_errors = 0;
stripe->init_nr_meta_errors = 0;
stripe->error_bitmap = 0;
stripe->io_error_bitmap = 0;
stripe->csum_error_bitmap = 0;
stripe->meta_error_bitmap = 0;
}
/*
* Locate one stripe which has at least one extent in its range.
*
* Return 0 if found such stripe, and store its info into @stripe.
* Return >0 if there is no such stripe in the specified range.
* Return <0 for error.
*/
static int scrub_find_fill_first_stripe(struct btrfs_block_group *bg,
struct btrfs_path *extent_path,
struct btrfs_path *csum_path,
struct btrfs_device *dev, u64 physical,
int mirror_num, u64 logical_start,
u32 logical_len,
struct scrub_stripe *stripe)
{
struct btrfs_fs_info *fs_info = bg->fs_info;
struct btrfs_root *extent_root = btrfs_extent_root(fs_info, bg->start);
struct btrfs_root *csum_root = btrfs_csum_root(fs_info, bg->start);
const u64 logical_end = logical_start + logical_len;
u64 cur_logical = logical_start;
u64 stripe_end;
u64 extent_start;
u64 extent_len;
u64 extent_flags;
u64 extent_gen;
int ret;
memset(stripe->sectors, 0, sizeof(struct scrub_sector_verification) *
stripe->nr_sectors);
scrub_stripe_reset_bitmaps(stripe);
/* The range must be inside the bg. */
ASSERT(logical_start >= bg->start && logical_end <= bg->start + bg->length);
ret = find_first_extent_item(extent_root, extent_path, logical_start,
logical_len);
/* Either error or not found. */
if (ret)
goto out;
get_extent_info(extent_path, &extent_start, &extent_len, &extent_flags,
&extent_gen);
if (extent_flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
stripe->nr_meta_extents++;
if (extent_flags & BTRFS_EXTENT_FLAG_DATA)
stripe->nr_data_extents++;
cur_logical = max(extent_start, cur_logical);
/*
* Round down to stripe boundary.
*
* The extra calculation against bg->start is to handle block groups
* whose logical bytenr is not BTRFS_STRIPE_LEN aligned.
*/
stripe->logical = round_down(cur_logical - bg->start, BTRFS_STRIPE_LEN) +
bg->start;
stripe->physical = physical + stripe->logical - logical_start;
stripe->dev = dev;
stripe->bg = bg;
stripe->mirror_num = mirror_num;
stripe_end = stripe->logical + BTRFS_STRIPE_LEN - 1;
/* Fill the first extent info into stripe->sectors[] array. */
fill_one_extent_info(fs_info, stripe, extent_start, extent_len,
extent_flags, extent_gen);
cur_logical = extent_start + extent_len;
/* Fill the extent info for the remaining sectors. */
while (cur_logical <= stripe_end) {
ret = find_first_extent_item(extent_root, extent_path, cur_logical,
stripe_end - cur_logical + 1);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
break;
}
get_extent_info(extent_path, &extent_start, &extent_len,
&extent_flags, &extent_gen);
if (extent_flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
stripe->nr_meta_extents++;
if (extent_flags & BTRFS_EXTENT_FLAG_DATA)
stripe->nr_data_extents++;
fill_one_extent_info(fs_info, stripe, extent_start, extent_len,
extent_flags, extent_gen);
cur_logical = extent_start + extent_len;
}
/* Now fill the data csum. */
if (bg->flags & BTRFS_BLOCK_GROUP_DATA) {
int sector_nr;
unsigned long csum_bitmap = 0;
/* Csum space should have already been allocated. */
ASSERT(stripe->csums);
/*
* Our csum bitmap should be large enough, as BTRFS_STRIPE_LEN
* should contain at most 16 sectors.
*/
ASSERT(BITS_PER_LONG >= BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits);
ret = btrfs_lookup_csums_bitmap(csum_root, csum_path,
stripe->logical, stripe_end,
stripe->csums, &csum_bitmap);
if (ret < 0)
goto out;
if (ret > 0)
ret = 0;
for_each_set_bit(sector_nr, &csum_bitmap, stripe->nr_sectors) {
stripe->sectors[sector_nr].csum = stripe->csums +
sector_nr * fs_info->csum_size;
}
}
set_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &stripe->state);
out:
return ret;
}
static void scrub_reset_stripe(struct scrub_stripe *stripe)
{
scrub_stripe_reset_bitmaps(stripe);
stripe->nr_meta_extents = 0;
stripe->nr_data_extents = 0;
stripe->state = 0;
for (int i = 0; i < stripe->nr_sectors; i++) {
stripe->sectors[i].is_metadata = false;
stripe->sectors[i].csum = NULL;
stripe->sectors[i].generation = 0;
}
}
static void scrub_submit_extent_sector_read(struct scrub_ctx *sctx,
struct scrub_stripe *stripe)
{
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
struct btrfs_bio *bbio = NULL;
unsigned int nr_sectors = min(BTRFS_STRIPE_LEN, stripe->bg->start +
stripe->bg->length - stripe->logical) >>
fs_info->sectorsize_bits;
u64 stripe_len = BTRFS_STRIPE_LEN;
int mirror = stripe->mirror_num;
int i;
atomic_inc(&stripe->pending_io);
for_each_set_bit(i, &stripe->extent_sector_bitmap, stripe->nr_sectors) {
struct page *page = scrub_stripe_get_page(stripe, i);
unsigned int pgoff = scrub_stripe_get_page_offset(stripe, i);
/* We're beyond the chunk boundary, no need to read anymore. */
if (i >= nr_sectors)
break;
/* The current sector cannot be merged, submit the bio. */
if (bbio &&
((i > 0 &&
!test_bit(i - 1, &stripe->extent_sector_bitmap)) ||
bbio->bio.bi_iter.bi_size >= stripe_len)) {
ASSERT(bbio->bio.bi_iter.bi_size);
atomic_inc(&stripe->pending_io);
btrfs_submit_bio(bbio, mirror);
bbio = NULL;
}
if (!bbio) {
struct btrfs_io_stripe io_stripe = {};
struct btrfs_io_context *bioc = NULL;
const u64 logical = stripe->logical +
(i << fs_info->sectorsize_bits);
int err;
io_stripe.is_scrub = true;
stripe_len = (nr_sectors - i) << fs_info->sectorsize_bits;
/*
* For RST cases, we need to manually split the bbio to
* follow the RST boundary.
*/
err = btrfs_map_block(fs_info, BTRFS_MAP_READ, logical,
&stripe_len, &bioc, &io_stripe, &mirror);
btrfs_put_bioc(bioc);
if (err < 0) {
set_bit(i, &stripe->io_error_bitmap);
set_bit(i, &stripe->error_bitmap);
continue;
}
bbio = btrfs_bio_alloc(stripe->nr_sectors, REQ_OP_READ,
fs_info, scrub_read_endio, stripe);
bbio->bio.bi_iter.bi_sector = logical >> SECTOR_SHIFT;
}
__bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff);
}
if (bbio) {
ASSERT(bbio->bio.bi_iter.bi_size);
atomic_inc(&stripe->pending_io);
btrfs_submit_bio(bbio, mirror);
}
if (atomic_dec_and_test(&stripe->pending_io)) {
wake_up(&stripe->io_wait);
INIT_WORK(&stripe->work, scrub_stripe_read_repair_worker);
queue_work(stripe->bg->fs_info->scrub_workers, &stripe->work);
}
}
static void scrub_submit_initial_read(struct scrub_ctx *sctx,
struct scrub_stripe *stripe)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
struct btrfs_bio *bbio;
unsigned int nr_sectors = min(BTRFS_STRIPE_LEN, stripe->bg->start +
stripe->bg->length - stripe->logical) >>
fs_info->sectorsize_bits;
int mirror = stripe->mirror_num;
ASSERT(stripe->bg);
ASSERT(stripe->mirror_num > 0);
ASSERT(test_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &stripe->state));
if (btrfs_need_stripe_tree_update(fs_info, stripe->bg->flags)) {
scrub_submit_extent_sector_read(sctx, stripe);
return;
}
bbio = btrfs_bio_alloc(SCRUB_STRIPE_PAGES, REQ_OP_READ, fs_info,
scrub_read_endio, stripe);
bbio->bio.bi_iter.bi_sector = stripe->logical >> SECTOR_SHIFT;
/* Read the whole range inside the chunk boundary. */
for (unsigned int cur = 0; cur < nr_sectors; cur++) {
struct page *page = scrub_stripe_get_page(stripe, cur);
unsigned int pgoff = scrub_stripe_get_page_offset(stripe, cur);
int ret;
ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff);
/* We should have allocated enough bio vectors. */
ASSERT(ret == fs_info->sectorsize);
}
atomic_inc(&stripe->pending_io);
/*
* For dev-replace, either user asks to avoid the source dev, or
* the device is missing, we try the next mirror instead.
*/
if (sctx->is_dev_replace &&
(fs_info->dev_replace.cont_reading_from_srcdev_mode ==
BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID ||
!stripe->dev->bdev)) {
int num_copies = btrfs_num_copies(fs_info, stripe->bg->start,
stripe->bg->length);
mirror = calc_next_mirror(mirror, num_copies);
}
btrfs_submit_bio(bbio, mirror);
}
static bool stripe_has_metadata_error(struct scrub_stripe *stripe)
{
int i;
for_each_set_bit(i, &stripe->error_bitmap, stripe->nr_sectors) {
if (stripe->sectors[i].is_metadata) {
struct btrfs_fs_info *fs_info = stripe->bg->fs_info;
btrfs_err(fs_info,
"stripe %llu has unrepaired metadata sector at %llu",
stripe->logical,
stripe->logical + (i << fs_info->sectorsize_bits));
return true;
}
}
return false;
}
static void submit_initial_group_read(struct scrub_ctx *sctx,
unsigned int first_slot,
unsigned int nr_stripes)
{
struct blk_plug plug;
ASSERT(first_slot < SCRUB_TOTAL_STRIPES);
ASSERT(first_slot + nr_stripes <= SCRUB_TOTAL_STRIPES);
scrub_throttle_dev_io(sctx, sctx->stripes[0].dev,
btrfs_stripe_nr_to_offset(nr_stripes));
blk_start_plug(&plug);
for (int i = 0; i < nr_stripes; i++) {
struct scrub_stripe *stripe = &sctx->stripes[first_slot + i];
/* Those stripes should be initialized. */
ASSERT(test_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &stripe->state));
scrub_submit_initial_read(sctx, stripe);
}
blk_finish_plug(&plug);
}
static int flush_scrub_stripes(struct scrub_ctx *sctx)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
struct scrub_stripe *stripe;
const int nr_stripes = sctx->cur_stripe;
int ret = 0;
if (!nr_stripes)
return 0;
ASSERT(test_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &sctx->stripes[0].state));
/* Submit the stripes which are populated but not submitted. */
if (nr_stripes % SCRUB_STRIPES_PER_GROUP) {
const int first_slot = round_down(nr_stripes, SCRUB_STRIPES_PER_GROUP);
submit_initial_group_read(sctx, first_slot, nr_stripes - first_slot);
}
for (int i = 0; i < nr_stripes; i++) {
stripe = &sctx->stripes[i];
wait_event(stripe->repair_wait,
test_bit(SCRUB_STRIPE_FLAG_REPAIR_DONE, &stripe->state));
}
/* Submit for dev-replace. */
if (sctx->is_dev_replace) {
/*
* For dev-replace, if we know there is something wrong with
* metadata, we should immediately abort.
*/
for (int i = 0; i < nr_stripes; i++) {
if (stripe_has_metadata_error(&sctx->stripes[i])) {
ret = -EIO;
goto out;
}
}
for (int i = 0; i < nr_stripes; i++) {
unsigned long good;
stripe = &sctx->stripes[i];
ASSERT(stripe->dev == fs_info->dev_replace.srcdev);
bitmap_andnot(&good, &stripe->extent_sector_bitmap,
&stripe->error_bitmap, stripe->nr_sectors);
scrub_write_sectors(sctx, stripe, good, true);
}
}
/* Wait for the above writebacks to finish. */
for (int i = 0; i < nr_stripes; i++) {
stripe = &sctx->stripes[i];
wait_scrub_stripe_io(stripe);
scrub_reset_stripe(stripe);
}
out:
sctx->cur_stripe = 0;
return ret;
}
static void raid56_scrub_wait_endio(struct bio *bio)
{
complete(bio->bi_private);
}
static int queue_scrub_stripe(struct scrub_ctx *sctx, struct btrfs_block_group *bg,
struct btrfs_device *dev, int mirror_num,
u64 logical, u32 length, u64 physical,
u64 *found_logical_ret)
{
struct scrub_stripe *stripe;
int ret;
/*
* There should always be one slot left, as caller filling the last
* slot should flush them all.
*/
ASSERT(sctx->cur_stripe < SCRUB_TOTAL_STRIPES);
/* @found_logical_ret must be specified. */
ASSERT(found_logical_ret);
stripe = &sctx->stripes[sctx->cur_stripe];
scrub_reset_stripe(stripe);
ret = scrub_find_fill_first_stripe(bg, &sctx->extent_path,
&sctx->csum_path, dev, physical,
mirror_num, logical, length, stripe);
/* Either >0 as no more extents or <0 for error. */
if (ret)
return ret;
*found_logical_ret = stripe->logical;
sctx->cur_stripe++;
/* We filled one group, submit it. */
if (sctx->cur_stripe % SCRUB_STRIPES_PER_GROUP == 0) {
const int first_slot = sctx->cur_stripe - SCRUB_STRIPES_PER_GROUP;
submit_initial_group_read(sctx, first_slot, SCRUB_STRIPES_PER_GROUP);
}
/* Last slot used, flush them all. */
if (sctx->cur_stripe == SCRUB_TOTAL_STRIPES)
return flush_scrub_stripes(sctx);
return 0;
}
static int scrub_raid56_parity_stripe(struct scrub_ctx *sctx,
struct btrfs_device *scrub_dev,
struct btrfs_block_group *bg,
struct btrfs_chunk_map *map,
u64 full_stripe_start)
{
DECLARE_COMPLETION_ONSTACK(io_done);
struct btrfs_fs_info *fs_info = sctx->fs_info;
struct btrfs_raid_bio *rbio;
struct btrfs_io_context *bioc = NULL;
struct btrfs_path extent_path = { 0 };
struct btrfs_path csum_path = { 0 };
struct bio *bio;
struct scrub_stripe *stripe;
bool all_empty = true;
const int data_stripes = nr_data_stripes(map);
unsigned long extent_bitmap = 0;
u64 length = btrfs_stripe_nr_to_offset(data_stripes);
int ret;
ASSERT(sctx->raid56_data_stripes);
/*
* For data stripe search, we cannot re-use the same extent/csum paths,
* as the data stripe bytenr may be smaller than previous extent. Thus
* we have to use our own extent/csum paths.
*/
extent_path.search_commit_root = 1;
extent_path.skip_locking = 1;
csum_path.search_commit_root = 1;
csum_path.skip_locking = 1;
for (int i = 0; i < data_stripes; i++) {
int stripe_index;
int rot;
u64 physical;
stripe = &sctx->raid56_data_stripes[i];
rot = div_u64(full_stripe_start - bg->start,
data_stripes) >> BTRFS_STRIPE_LEN_SHIFT;
stripe_index = (i + rot) % map->num_stripes;
physical = map->stripes[stripe_index].physical +
btrfs_stripe_nr_to_offset(rot);
scrub_reset_stripe(stripe);
set_bit(SCRUB_STRIPE_FLAG_NO_REPORT, &stripe->state);
ret = scrub_find_fill_first_stripe(bg, &extent_path, &csum_path,
map->stripes[stripe_index].dev, physical, 1,
full_stripe_start + btrfs_stripe_nr_to_offset(i),
BTRFS_STRIPE_LEN, stripe);
if (ret < 0)
goto out;
/*
* No extent in this data stripe, need to manually mark them
* initialized to make later read submission happy.
*/
if (ret > 0) {
stripe->logical = full_stripe_start +
btrfs_stripe_nr_to_offset(i);
stripe->dev = map->stripes[stripe_index].dev;
stripe->mirror_num = 1;
set_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &stripe->state);
}
}
/* Check if all data stripes are empty. */
for (int i = 0; i < data_stripes; i++) {
stripe = &sctx->raid56_data_stripes[i];
if (!bitmap_empty(&stripe->extent_sector_bitmap, stripe->nr_sectors)) {
all_empty = false;
break;
}
}
if (all_empty) {
ret = 0;
goto out;
}
for (int i = 0; i < data_stripes; i++) {
stripe = &sctx->raid56_data_stripes[i];
scrub_submit_initial_read(sctx, stripe);
}
for (int i = 0; i < data_stripes; i++) {
stripe = &sctx->raid56_data_stripes[i];
wait_event(stripe->repair_wait,
test_bit(SCRUB_STRIPE_FLAG_REPAIR_DONE, &stripe->state));
}
/* For now, no zoned support for RAID56. */
ASSERT(!btrfs_is_zoned(sctx->fs_info));
/*
* Now all data stripes are properly verified. Check if we have any
* unrepaired, if so abort immediately or we could further corrupt the
* P/Q stripes.
*
* During the loop, also populate extent_bitmap.
*/
for (int i = 0; i < data_stripes; i++) {
unsigned long error;
stripe = &sctx->raid56_data_stripes[i];
/*
* We should only check the errors where there is an extent.
* As we may hit an empty data stripe while it's missing.
*/
bitmap_and(&error, &stripe->error_bitmap,
&stripe->extent_sector_bitmap, stripe->nr_sectors);
if (!bitmap_empty(&error, stripe->nr_sectors)) {
btrfs_err(fs_info,
"unrepaired sectors detected, full stripe %llu data stripe %u errors %*pbl",
full_stripe_start, i, stripe->nr_sectors,
&error);
ret = -EIO;
goto out;
}
bitmap_or(&extent_bitmap, &extent_bitmap,
&stripe->extent_sector_bitmap, stripe->nr_sectors);
}
/* Now we can check and regenerate the P/Q stripe. */
bio = bio_alloc(NULL, 1, REQ_OP_READ, GFP_NOFS);
bio->bi_iter.bi_sector = full_stripe_start >> SECTOR_SHIFT;
bio->bi_private = &io_done;
bio->bi_end_io = raid56_scrub_wait_endio;
btrfs_bio_counter_inc_blocked(fs_info);
ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, full_stripe_start,
&length, &bioc, NULL, NULL);
if (ret < 0) {
btrfs_put_bioc(bioc);
btrfs_bio_counter_dec(fs_info);
goto out;
}
rbio = raid56_parity_alloc_scrub_rbio(bio, bioc, scrub_dev, &extent_bitmap,
BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits);
btrfs_put_bioc(bioc);
if (!rbio) {
ret = -ENOMEM;
btrfs_bio_counter_dec(fs_info);
goto out;
}
/* Use the recovered stripes as cache to avoid read them from disk again. */
for (int i = 0; i < data_stripes; i++) {
stripe = &sctx->raid56_data_stripes[i];
raid56_parity_cache_data_pages(rbio, stripe->pages,
full_stripe_start + (i << BTRFS_STRIPE_LEN_SHIFT));
}
raid56_parity_submit_scrub_rbio(rbio);
wait_for_completion_io(&io_done);
ret = blk_status_to_errno(bio->bi_status);
bio_put(bio);
btrfs_bio_counter_dec(fs_info);
btrfs_release_path(&extent_path);
btrfs_release_path(&csum_path);
out:
return ret;
}
/*
* Scrub one range which can only has simple mirror based profile.
* (Including all range in SINGLE/DUP/RAID1/RAID1C*, and each stripe in
* RAID0/RAID10).
*
* Since we may need to handle a subset of block group, we need @logical_start
* and @logical_length parameter.
*/
static int scrub_simple_mirror(struct scrub_ctx *sctx,
struct btrfs_block_group *bg,
struct btrfs_chunk_map *map,
u64 logical_start, u64 logical_length,
struct btrfs_device *device,
u64 physical, int mirror_num)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
const u64 logical_end = logical_start + logical_length;
u64 cur_logical = logical_start;
int ret = 0;
/* The range must be inside the bg */
ASSERT(logical_start >= bg->start && logical_end <= bg->start + bg->length);
/* Go through each extent items inside the logical range */
while (cur_logical < logical_end) {
u64 found_logical = U64_MAX;
u64 cur_physical = physical + cur_logical - logical_start;
/* Canceled? */
if (atomic_read(&fs_info->scrub_cancel_req) ||
atomic_read(&sctx->cancel_req)) {
ret = -ECANCELED;
break;
}
/* Paused? */
if (atomic_read(&fs_info->scrub_pause_req)) {
/* Push queued extents */
scrub_blocked_if_needed(fs_info);
}
/* Block group removed? */
spin_lock(&bg->lock);
if (test_bit(BLOCK_GROUP_FLAG_REMOVED, &bg->runtime_flags)) {
spin_unlock(&bg->lock);
ret = 0;
break;
}
spin_unlock(&bg->lock);
ret = queue_scrub_stripe(sctx, bg, device, mirror_num,
cur_logical, logical_end - cur_logical,
cur_physical, &found_logical);
if (ret > 0) {
/* No more extent, just update the accounting */
sctx->stat.last_physical = physical + logical_length;
ret = 0;
break;
}
if (ret < 0)
break;
/* queue_scrub_stripe() returned 0, @found_logical must be updated. */
ASSERT(found_logical != U64_MAX);
cur_logical = found_logical + BTRFS_STRIPE_LEN;
/* Don't hold CPU for too long time */
cond_resched();
}
return ret;
}
/* Calculate the full stripe length for simple stripe based profiles */
static u64 simple_stripe_full_stripe_len(const struct btrfs_chunk_map *map)
{
ASSERT(map->type & (BTRFS_BLOCK_GROUP_RAID0 |
BTRFS_BLOCK_GROUP_RAID10));
return btrfs_stripe_nr_to_offset(map->num_stripes / map->sub_stripes);
}
/* Get the logical bytenr for the stripe */
static u64 simple_stripe_get_logical(struct btrfs_chunk_map *map,
struct btrfs_block_group *bg,
int stripe_index)
{
ASSERT(map->type & (BTRFS_BLOCK_GROUP_RAID0 |
BTRFS_BLOCK_GROUP_RAID10));
ASSERT(stripe_index < map->num_stripes);
/*
* (stripe_index / sub_stripes) gives how many data stripes we need to
* skip.
*/
return btrfs_stripe_nr_to_offset(stripe_index / map->sub_stripes) +
bg->start;
}
/* Get the mirror number for the stripe */
static int simple_stripe_mirror_num(struct btrfs_chunk_map *map, int stripe_index)
{
ASSERT(map->type & (BTRFS_BLOCK_GROUP_RAID0 |
BTRFS_BLOCK_GROUP_RAID10));
ASSERT(stripe_index < map->num_stripes);
/* For RAID0, it's fixed to 1, for RAID10 it's 0,1,0,1... */
return stripe_index % map->sub_stripes + 1;
}
static int scrub_simple_stripe(struct scrub_ctx *sctx,
struct btrfs_block_group *bg,
struct btrfs_chunk_map *map,
struct btrfs_device *device,
int stripe_index)
{
const u64 logical_increment = simple_stripe_full_stripe_len(map);
const u64 orig_logical = simple_stripe_get_logical(map, bg, stripe_index);
const u64 orig_physical = map->stripes[stripe_index].physical;
const int mirror_num = simple_stripe_mirror_num(map, stripe_index);
u64 cur_logical = orig_logical;
u64 cur_physical = orig_physical;
int ret = 0;
while (cur_logical < bg->start + bg->length) {
/*
* Inside each stripe, RAID0 is just SINGLE, and RAID10 is
* just RAID1, so we can reuse scrub_simple_mirror() to scrub
* this stripe.
*/
ret = scrub_simple_mirror(sctx, bg, map, cur_logical,
BTRFS_STRIPE_LEN, device, cur_physical,
mirror_num);
if (ret)
return ret;
/* Skip to next stripe which belongs to the target device */
cur_logical += logical_increment;
/* For physical offset, we just go to next stripe */
cur_physical += BTRFS_STRIPE_LEN;
}
return ret;
}
static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
struct btrfs_block_group *bg,
struct btrfs_chunk_map *map,
struct btrfs_device *scrub_dev,
int stripe_index)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
const u64 profile = map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK;
const u64 chunk_logical = bg->start;
int ret;
int ret2;
u64 physical = map->stripes[stripe_index].physical;
const u64 dev_stripe_len = btrfs_calc_stripe_length(map);
const u64 physical_end = physical + dev_stripe_len;
u64 logical;
u64 logic_end;
/* The logical increment after finishing one stripe */
u64 increment;
/* Offset inside the chunk */
u64 offset;
u64 stripe_logical;
int stop_loop = 0;
/* Extent_path should be released by now. */
ASSERT(sctx->extent_path.nodes[0] == NULL);
scrub_blocked_if_needed(fs_info);
if (sctx->is_dev_replace &&
btrfs_dev_is_sequential(sctx->wr_tgtdev, physical)) {
mutex_lock(&sctx->wr_lock);
sctx->write_pointer = physical;
mutex_unlock(&sctx->wr_lock);
}
/* Prepare the extra data stripes used by RAID56. */
if (profile & BTRFS_BLOCK_GROUP_RAID56_MASK) {
ASSERT(sctx->raid56_data_stripes == NULL);
sctx->raid56_data_stripes = kcalloc(nr_data_stripes(map),
sizeof(struct scrub_stripe),
GFP_KERNEL);
if (!sctx->raid56_data_stripes) {
ret = -ENOMEM;
goto out;
}
for (int i = 0; i < nr_data_stripes(map); i++) {
ret = init_scrub_stripe(fs_info,
&sctx->raid56_data_stripes[i]);
if (ret < 0)
goto out;
sctx->raid56_data_stripes[i].bg = bg;
sctx->raid56_data_stripes[i].sctx = sctx;
}
}
/*
* There used to be a big double loop to handle all profiles using the
* same routine, which grows larger and more gross over time.
*
* So here we handle each profile differently, so simpler profiles
* have simpler scrubbing function.
*/
if (!(profile & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10 |
BTRFS_BLOCK_GROUP_RAID56_MASK))) {
/*
* Above check rules out all complex profile, the remaining
* profiles are SINGLE|DUP|RAID1|RAID1C*, which is simple
* mirrored duplication without stripe.
*
* Only @physical and @mirror_num needs to calculated using
* @stripe_index.
*/
ret = scrub_simple_mirror(sctx, bg, map, bg->start, bg->length,
scrub_dev, map->stripes[stripe_index].physical,
stripe_index + 1);
offset = 0;
goto out;
}
if (profile & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) {
ret = scrub_simple_stripe(sctx, bg, map, scrub_dev, stripe_index);
offset = btrfs_stripe_nr_to_offset(stripe_index / map->sub_stripes);
goto out;
}
/* Only RAID56 goes through the old code */
ASSERT(map->type & BTRFS_BLOCK_GROUP_RAID56_MASK);
ret = 0;
/* Calculate the logical end of the stripe */
get_raid56_logic_offset(physical_end, stripe_index,
map, &logic_end, NULL);
logic_end += chunk_logical;
/* Initialize @offset in case we need to go to out: label */
get_raid56_logic_offset(physical, stripe_index, map, &offset, NULL);
increment = btrfs_stripe_nr_to_offset(nr_data_stripes(map));
/*
* Due to the rotation, for RAID56 it's better to iterate each stripe
* using their physical offset.
*/
while (physical < physical_end) {
ret = get_raid56_logic_offset(physical, stripe_index, map,
&logical, &stripe_logical);
logical += chunk_logical;
if (ret) {
/* it is parity strip */
stripe_logical += chunk_logical;
ret = scrub_raid56_parity_stripe(sctx, scrub_dev, bg,
map, stripe_logical);
if (ret)
goto out;
goto next;
}
/*
* Now we're at a data stripe, scrub each extents in the range.
*
* At this stage, if we ignore the repair part, inside each data
* stripe it is no different than SINGLE profile.
* We can reuse scrub_simple_mirror() here, as the repair part
* is still based on @mirror_num.
*/
ret = scrub_simple_mirror(sctx, bg, map, logical, BTRFS_STRIPE_LEN,
scrub_dev, physical, 1);
if (ret < 0)
goto out;
next:
logical += increment;
physical += BTRFS_STRIPE_LEN;
spin_lock(&sctx->stat_lock);
if (stop_loop)
sctx->stat.last_physical =
map->stripes[stripe_index].physical + dev_stripe_len;
else
sctx->stat.last_physical = physical;
spin_unlock(&sctx->stat_lock);
if (stop_loop)
break;
}
out:
ret2 = flush_scrub_stripes(sctx);
if (!ret)
ret = ret2;
btrfs_release_path(&sctx->extent_path);
btrfs_release_path(&sctx->csum_path);
if (sctx->raid56_data_stripes) {
for (int i = 0; i < nr_data_stripes(map); i++)
release_scrub_stripe(&sctx->raid56_data_stripes[i]);
kfree(sctx->raid56_data_stripes);
sctx->raid56_data_stripes = NULL;
}
if (sctx->is_dev_replace && ret >= 0) {
int ret2;
ret2 = sync_write_pointer_for_zoned(sctx,
chunk_logical + offset,
map->stripes[stripe_index].physical,
physical_end);
if (ret2)
ret = ret2;
}
return ret < 0 ? ret : 0;
}
static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
struct btrfs_block_group *bg,
struct btrfs_device *scrub_dev,
u64 dev_offset,
u64 dev_extent_len)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
struct btrfs_chunk_map *map;
int i;
int ret = 0;
map = btrfs_find_chunk_map(fs_info, bg->start, bg->length);
if (!map) {
/*
* Might have been an unused block group deleted by the cleaner
* kthread or relocation.
*/
spin_lock(&bg->lock);
if (!test_bit(BLOCK_GROUP_FLAG_REMOVED, &bg->runtime_flags))
ret = -EINVAL;
spin_unlock(&bg->lock);
return ret;
}
if (map->start != bg->start)
goto out;
if (map->chunk_len < dev_extent_len)
goto out;
for (i = 0; i < map->num_stripes; ++i) {
if (map->stripes[i].dev->bdev == scrub_dev->bdev &&
map->stripes[i].physical == dev_offset) {
ret = scrub_stripe(sctx, bg, map, scrub_dev, i);
if (ret)
goto out;
}
}
out:
btrfs_free_chunk_map(map);
return ret;
}
static int finish_extent_writes_for_zoned(struct btrfs_root *root,
struct btrfs_block_group *cache)
{
struct btrfs_fs_info *fs_info = cache->fs_info;
if (!btrfs_is_zoned(fs_info))
return 0;
btrfs_wait_block_group_reservations(cache);
btrfs_wait_nocow_writers(cache);
btrfs_wait_ordered_roots(fs_info, U64_MAX, cache);
return btrfs_commit_current_transaction(root);
}
static noinline_for_stack
int scrub_enumerate_chunks(struct scrub_ctx *sctx,
struct btrfs_device *scrub_dev, u64 start, u64 end)
{
struct btrfs_dev_extent *dev_extent = NULL;
struct btrfs_path *path;
struct btrfs_fs_info *fs_info = sctx->fs_info;
struct btrfs_root *root = fs_info->dev_root;
u64 chunk_offset;
int ret = 0;
int ro_set;
int slot;
struct extent_buffer *l;
struct btrfs_key key;
struct btrfs_key found_key;
struct btrfs_block_group *cache;
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = READA_FORWARD;
path->search_commit_root = 1;
path->skip_locking = 1;
key.objectid = scrub_dev->devid;
key.offset = 0ull;
key.type = BTRFS_DEV_EXTENT_KEY;
while (1) {
u64 dev_extent_len;
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 < 0)
break;
if (ret > 0) {
ret = 0;
break;
}
} else {
ret = 0;
}
}
l = path->nodes[0];
slot = path->slots[0];
btrfs_item_key_to_cpu(l, &found_key, slot);
if (found_key.objectid != scrub_dev->devid)
break;
if (found_key.type != 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);
dev_extent_len = btrfs_dev_extent_length(l, dev_extent);
if (found_key.offset + dev_extent_len <= start)
goto skip;
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);
/* some chunks are removed but not committed to disk yet,
* continue scrubbing */
if (!cache)
goto skip;
ASSERT(cache->start <= chunk_offset);
/*
* We are using the commit root to search for device extents, so
* that means we could have found a device extent item from a
* block group that was deleted in the current transaction. The
* logical start offset of the deleted block group, stored at
* @chunk_offset, might be part of the logical address range of
* a new block group (which uses different physical extents).
* In this case btrfs_lookup_block_group() has returned the new
* block group, and its start address is less than @chunk_offset.
*
* We skip such new block groups, because it's pointless to
* process them, as we won't find their extents because we search
* for them using the commit root of the extent tree. For a device
* replace it's also fine to skip it, we won't miss copying them
* to the target device because we have the write duplication
* setup through the regular write path (by btrfs_map_block()),
* and we have committed a transaction when we started the device
* replace, right after setting up the device replace state.
*/
if (cache->start < chunk_offset) {
btrfs_put_block_group(cache);
goto skip;
}
if (sctx->is_dev_replace && btrfs_is_zoned(fs_info)) {
if (!test_bit(BLOCK_GROUP_FLAG_TO_COPY, &cache->runtime_flags)) {
btrfs_put_block_group(cache);
goto skip;
}
}
/*
* Make sure that while we are scrubbing the corresponding block
* group doesn't get its logical address and its device extents
* reused for another block group, which can possibly be of a
* different type and different profile. We do this to prevent
* false error detections and crashes due to bogus attempts to
* repair extents.
*/
spin_lock(&cache->lock);
if (test_bit(BLOCK_GROUP_FLAG_REMOVED, &cache->runtime_flags)) {
spin_unlock(&cache->lock);
btrfs_put_block_group(cache);
goto skip;
}
btrfs_freeze_block_group(cache);
spin_unlock(&cache->lock);
/*
* we need call btrfs_inc_block_group_ro() with scrubs_paused,
* to avoid deadlock caused by:
* btrfs_inc_block_group_ro()
* -> btrfs_wait_for_commit()
* -> btrfs_commit_transaction()
* -> btrfs_scrub_pause()
*/
scrub_pause_on(fs_info);
/*
* Don't do chunk preallocation for scrub.
*
* This is especially important for SYSTEM bgs, or we can hit
* -EFBIG from btrfs_finish_chunk_alloc() like:
* 1. The only SYSTEM bg is marked RO.
* Since SYSTEM bg is small, that's pretty common.
* 2. New SYSTEM bg will be allocated
* Due to regular version will allocate new chunk.
* 3. New SYSTEM bg is empty and will get cleaned up
* Before cleanup really happens, it's marked RO again.
* 4. Empty SYSTEM bg get scrubbed
* We go back to 2.
*
* This can easily boost the amount of SYSTEM chunks if cleaner
* thread can't be triggered fast enough, and use up all space
* of btrfs_super_block::sys_chunk_array
*
* While for dev replace, we need to try our best to mark block
* group RO, to prevent race between:
* - Write duplication
* Contains latest data
* - Scrub copy
* Contains data from commit tree
*
* If target block group is not marked RO, nocow writes can
* be overwritten by scrub copy, causing data corruption.
* So for dev-replace, it's not allowed to continue if a block
* group is not RO.
*/
ret = btrfs_inc_block_group_ro(cache, sctx->is_dev_replace);
if (!ret && sctx->is_dev_replace) {
ret = finish_extent_writes_for_zoned(root, cache);
if (ret) {
btrfs_dec_block_group_ro(cache);
scrub_pause_off(fs_info);
btrfs_put_block_group(cache);
break;
}
}
if (ret == 0) {
ro_set = 1;
} else if (ret == -ENOSPC && !sctx->is_dev_replace &&
!(cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK)) {
/*
* btrfs_inc_block_group_ro return -ENOSPC when it
* failed in creating new chunk for metadata.
* It is not a problem for scrub, because
* metadata are always cowed, and our scrub paused
* commit_transactions.
*
* For RAID56 chunks, we have to mark them read-only
* for scrub, as later we would use our own cache
* out of RAID56 realm.
* Thus we want the RAID56 bg to be marked RO to
* prevent RMW from screwing up out cache.
*/
ro_set = 0;
} else if (ret == -ETXTBSY) {
btrfs_warn(fs_info,
"skipping scrub of block group %llu due to active swapfile",
cache->start);
scrub_pause_off(fs_info);
ret = 0;
goto skip_unfreeze;
} else {
btrfs_warn(fs_info,
"failed setting block group ro: %d", ret);
btrfs_unfreeze_block_group(cache);
btrfs_put_block_group(cache);
scrub_pause_off(fs_info);
break;
}
/*
* Now the target block is marked RO, wait for nocow writes to
* finish before dev-replace.
* COW is fine, as COW never overwrites extents in commit tree.
*/
if (sctx->is_dev_replace) {
btrfs_wait_nocow_writers(cache);
btrfs_wait_ordered_roots(fs_info, U64_MAX, cache);
}
scrub_pause_off(fs_info);
down_write(&dev_replace->rwsem);
dev_replace->cursor_right = found_key.offset + dev_extent_len;
dev_replace->cursor_left = found_key.offset;
dev_replace->item_needs_writeback = 1;
up_write(&dev_replace->rwsem);
ret = scrub_chunk(sctx, cache, scrub_dev, found_key.offset,
dev_extent_len);
if (sctx->is_dev_replace &&
!btrfs_finish_block_group_to_copy(dev_replace->srcdev,
cache, found_key.offset))
ro_set = 0;
down_write(&dev_replace->rwsem);
dev_replace->cursor_left = dev_replace->cursor_right;
dev_replace->item_needs_writeback = 1;
up_write(&dev_replace->rwsem);
if (ro_set)
btrfs_dec_block_group_ro(cache);
/*
* We might have prevented the cleaner kthread from deleting
* this block group if it was already unused because we raced
* and set it to RO mode first. So add it back to the unused
* list, otherwise it might not ever be deleted unless a manual
* balance is triggered or it becomes used and unused again.
*/
spin_lock(&cache->lock);
if (!test_bit(BLOCK_GROUP_FLAG_REMOVED, &cache->runtime_flags) &&
!cache->ro && cache->reserved == 0 && cache->used == 0) {
spin_unlock(&cache->lock);
if (btrfs_test_opt(fs_info, DISCARD_ASYNC))
btrfs_discard_queue_work(&fs_info->discard_ctl,
cache);
else
btrfs_mark_bg_unused(cache);
} else {
spin_unlock(&cache->lock);
}
skip_unfreeze:
btrfs_unfreeze_block_group(cache);
btrfs_put_block_group(cache);
if (ret)
break;
if (sctx->is_dev_replace &&
atomic64_read(&dev_replace->num_write_errors) > 0) {
ret = -EIO;
break;
}
if (sctx->stat.malloc_errors > 0) {
ret = -ENOMEM;
break;
}
skip:
key.offset = found_key.offset + dev_extent_len;
btrfs_release_path(path);
}
btrfs_free_path(path);
return ret;
}
static int scrub_one_super(struct scrub_ctx *sctx, struct btrfs_device *dev,
struct page *page, u64 physical, u64 generation)
{
struct btrfs_fs_info *fs_info = sctx->fs_info;
struct bio_vec bvec;
struct bio bio;
struct btrfs_super_block *sb = page_address(page);
int ret;
bio_init(&bio, dev->bdev, &bvec, 1, REQ_OP_READ);
bio.bi_iter.bi_sector = physical >> SECTOR_SHIFT;
__bio_add_page(&bio, page, BTRFS_SUPER_INFO_SIZE, 0);
ret = submit_bio_wait(&bio);
bio_uninit(&bio);
if (ret < 0)
return ret;
ret = btrfs_check_super_csum(fs_info, sb);
if (ret != 0) {
btrfs_err_rl(fs_info,
"super block at physical %llu devid %llu has bad csum",
physical, dev->devid);
return -EIO;
}
if (btrfs_super_generation(sb) != generation) {
btrfs_err_rl(fs_info,
"super block at physical %llu devid %llu has bad generation %llu expect %llu",
physical, dev->devid,
btrfs_super_generation(sb), generation);
return -EUCLEAN;
}
return btrfs_validate_super(fs_info, sb, -1);
}
static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
struct btrfs_device *scrub_dev)
{
int i;
u64 bytenr;
u64 gen;
int ret = 0;
struct page *page;
struct btrfs_fs_info *fs_info = sctx->fs_info;
if (BTRFS_FS_ERROR(fs_info))
return -EROFS;
page = alloc_page(GFP_KERNEL);
if (!page) {
spin_lock(&sctx->stat_lock);
sctx->stat.malloc_errors++;
spin_unlock(&sctx->stat_lock);
return -ENOMEM;
}
/* Seed devices of a new filesystem has their own generation. */
if (scrub_dev->fs_devices != fs_info->fs_devices)
gen = scrub_dev->generation;
else
gen = btrfs_get_last_trans_committed(fs_info);
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
ret = btrfs_sb_log_location(scrub_dev, i, 0, &bytenr);
if (ret == -ENOENT)
break;
if (ret) {
spin_lock(&sctx->stat_lock);
sctx->stat.super_errors++;
spin_unlock(&sctx->stat_lock);
continue;
}
if (bytenr + BTRFS_SUPER_INFO_SIZE >
scrub_dev->commit_total_bytes)
break;
if (!btrfs_check_super_location(scrub_dev, bytenr))
continue;
ret = scrub_one_super(sctx, scrub_dev, page, bytenr, gen);
if (ret) {
spin_lock(&sctx->stat_lock);
sctx->stat.super_errors++;
spin_unlock(&sctx->stat_lock);
}
}
__free_page(page);
return 0;
}
static void scrub_workers_put(struct btrfs_fs_info *fs_info)
{
if (refcount_dec_and_mutex_lock(&fs_info->scrub_workers_refcnt,
&fs_info->scrub_lock)) {
struct workqueue_struct *scrub_workers = fs_info->scrub_workers;
fs_info->scrub_workers = NULL;
mutex_unlock(&fs_info->scrub_lock);
if (scrub_workers)
destroy_workqueue(scrub_workers);
}
}
/*
* get a reference count on fs_info->scrub_workers. start worker if necessary
*/
static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info)
{
struct workqueue_struct *scrub_workers = NULL;
unsigned int flags = WQ_FREEZABLE | WQ_UNBOUND;
int max_active = fs_info->thread_pool_size;
int ret = -ENOMEM;
if (refcount_inc_not_zero(&fs_info->scrub_workers_refcnt))
return 0;
scrub_workers = alloc_workqueue("btrfs-scrub", flags, max_active);
if (!scrub_workers)
return -ENOMEM;
mutex_lock(&fs_info->scrub_lock);
if (refcount_read(&fs_info->scrub_workers_refcnt) == 0) {
ASSERT(fs_info->scrub_workers == NULL);
fs_info->scrub_workers = scrub_workers;
refcount_set(&fs_info->scrub_workers_refcnt, 1);
mutex_unlock(&fs_info->scrub_lock);
return 0;
}
/* Other thread raced in and created the workers for us */
refcount_inc(&fs_info->scrub_workers_refcnt);
mutex_unlock(&fs_info->scrub_lock);
ret = 0;
destroy_workqueue(scrub_workers);
return ret;
}
int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
u64 end, struct btrfs_scrub_progress *progress,
int readonly, int is_dev_replace)
{
struct btrfs_dev_lookup_args args = { .devid = devid };
struct scrub_ctx *sctx;
int ret;
struct btrfs_device *dev;
unsigned int nofs_flag;
bool need_commit = false;
if (btrfs_fs_closing(fs_info))
return -EAGAIN;
/* At mount time we have ensured nodesize is in the range of [4K, 64K]. */
ASSERT(fs_info->nodesize <= BTRFS_STRIPE_LEN);
/*
* SCRUB_MAX_SECTORS_PER_BLOCK is calculated using the largest possible
* value (max nodesize / min sectorsize), thus nodesize should always
* be fine.
*/
ASSERT(fs_info->nodesize <=
SCRUB_MAX_SECTORS_PER_BLOCK << fs_info->sectorsize_bits);
/* Allocate outside of device_list_mutex */
sctx = scrub_setup_ctx(fs_info, is_dev_replace);
if (IS_ERR(sctx))
return PTR_ERR(sctx);
ret = scrub_workers_get(fs_info);
if (ret)
goto out_free_ctx;
mutex_lock(&fs_info->fs_devices->device_list_mutex);
dev = btrfs_find_device(fs_info->fs_devices, &args);
if (!dev || (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) &&
!is_dev_replace)) {
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
ret = -ENODEV;
goto out;
}
if (!is_dev_replace && !readonly &&
!test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) {
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
btrfs_err_in_rcu(fs_info,
"scrub on devid %llu: filesystem on %s is not writable",
devid, btrfs_dev_name(dev));
ret = -EROFS;
goto out;
}
mutex_lock(&fs_info->scrub_lock);
if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &dev->dev_state)) {
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
ret = -EIO;
goto out;
}
down_read(&fs_info->dev_replace.rwsem);
if (dev->scrub_ctx ||
(!is_dev_replace &&
btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) {
up_read(&fs_info->dev_replace.rwsem);
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
ret = -EINPROGRESS;
goto out;
}
up_read(&fs_info->dev_replace.rwsem);
sctx->readonly = readonly;
dev->scrub_ctx = sctx;
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
/*
* checking @scrub_pause_req here, we can avoid
* race between committing transaction and scrubbing.
*/
__scrub_blocked_if_needed(fs_info);
atomic_inc(&fs_info->scrubs_running);
mutex_unlock(&fs_info->scrub_lock);
/*
* In order to avoid deadlock with reclaim when there is a transaction
* trying to pause scrub, make sure we use GFP_NOFS for all the
* allocations done at btrfs_scrub_sectors() and scrub_sectors_for_parity()
* invoked by our callees. The pausing request is done when the
* transaction commit starts, and it blocks the transaction until scrub
* is paused (done at specific points at scrub_stripe() or right above
* before incrementing fs_info->scrubs_running).
*/
nofs_flag = memalloc_nofs_save();
if (!is_dev_replace) {
u64 old_super_errors;
spin_lock(&sctx->stat_lock);
old_super_errors = sctx->stat.super_errors;
spin_unlock(&sctx->stat_lock);
btrfs_info(fs_info, "scrub: started on devid %llu", devid);
/*
* by holding device list mutex, we can
* kick off writing super in log tree sync.
*/
mutex_lock(&fs_info->fs_devices->device_list_mutex);
ret = scrub_supers(sctx, dev);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
spin_lock(&sctx->stat_lock);
/*
* Super block errors found, but we can not commit transaction
* at current context, since btrfs_commit_transaction() needs
* to pause the current running scrub (hold by ourselves).
*/
if (sctx->stat.super_errors > old_super_errors && !sctx->readonly)
need_commit = true;
spin_unlock(&sctx->stat_lock);
}
if (!ret)
ret = scrub_enumerate_chunks(sctx, dev, start, end);
memalloc_nofs_restore(nofs_flag);
atomic_dec(&fs_info->scrubs_running);
wake_up(&fs_info->scrub_pause_wait);
if (progress)
memcpy(progress, &sctx->stat, sizeof(*progress));
if (!is_dev_replace)
btrfs_info(fs_info, "scrub: %s on devid %llu with status: %d",
ret ? "not finished" : "finished", devid, ret);
mutex_lock(&fs_info->scrub_lock);
dev->scrub_ctx = NULL;
mutex_unlock(&fs_info->scrub_lock);
scrub_workers_put(fs_info);
scrub_put_ctx(sctx);
/*
* We found some super block errors before, now try to force a
* transaction commit, as scrub has finished.
*/
if (need_commit) {
struct btrfs_trans_handle *trans;
trans = btrfs_start_transaction(fs_info->tree_root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
btrfs_err(fs_info,
"scrub: failed to start transaction to fix super block errors: %d", ret);
return ret;
}
ret = btrfs_commit_transaction(trans);
if (ret < 0)
btrfs_err(fs_info,
"scrub: failed to commit transaction to fix super block errors: %d", ret);
}
return ret;
out:
scrub_workers_put(fs_info);
out_free_ctx:
scrub_free_ctx(sctx);
return ret;
}
void btrfs_scrub_pause(struct btrfs_fs_info *fs_info)
{
mutex_lock(&fs_info->scrub_lock);
atomic_inc(&fs_info->scrub_pause_req);
while (atomic_read(&fs_info->scrubs_paused)