Commit b5d67f64 authored by Stefan Behrens's avatar Stefan Behrens Committed by Chris Mason

Btrfs: change scrub to support big blocks

Scrub used to be coded for nodesize == leafsize == sectorsize == PAGE_SIZE.
This is now changed to support sizes for nodesize and leafsize which are
N * PAGE_SIZE.
Signed-off-by: default avatarStefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 1623edeb
......@@ -40,16 +40,26 @@
* - add a mode to also read unallocated space
*/
struct scrub_block;
struct scrub_dev;
#define SCRUB_PAGES_PER_BIO 16 /* 64k per bio */
#define SCRUB_BIOS_PER_DEV 16 /* 1 MB per device in flight */
#define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */
struct scrub_page {
struct scrub_block *sblock;
struct page *page;
struct block_device *bdev;
u64 flags; /* extent flags */
u64 generation;
int mirror_num;
int have_csum;
u64 logical;
u64 physical;
struct {
unsigned int mirror_num:8;
unsigned int have_csum:1;
unsigned int io_error:1;
};
u8 csum[BTRFS_CSUM_SIZE];
};
......@@ -60,12 +70,25 @@ struct scrub_bio {
int err;
u64 logical;
u64 physical;
struct scrub_page spag[SCRUB_PAGES_PER_BIO];
u64 count;
struct scrub_page *pagev[SCRUB_PAGES_PER_BIO];
int page_count;
int next_free;
struct btrfs_work work;
};
struct scrub_block {
struct scrub_page pagev[SCRUB_MAX_PAGES_PER_BLOCK];
int page_count;
atomic_t outstanding_pages;
atomic_t ref_count; /* free mem on transition to zero */
struct scrub_dev *sdev;
struct {
unsigned int header_error:1;
unsigned int checksum_error:1;
unsigned int no_io_error_seen:1;
};
};
struct scrub_dev {
struct scrub_bio *bios[SCRUB_BIOS_PER_DEV];
struct btrfs_device *dev;
......@@ -79,6 +102,10 @@ struct scrub_dev {
struct list_head csum_list;
atomic_t cancel_req;
int readonly;
int pages_per_bio; /* <= SCRUB_PAGES_PER_BIO */
u32 sectorsize;
u32 nodesize;
u32 leafsize;
/*
* statistics
*/
......@@ -107,19 +134,41 @@ struct scrub_warning {
int scratch_bufsize;
};
static int scrub_handle_errored_block(struct scrub_block *sblock_to_check);
static int scrub_setup_recheck_block(struct scrub_dev *sdev,
struct btrfs_mapping_tree *map_tree,
u64 length, u64 logical,
struct scrub_block *sblock);
static int scrub_recheck_block(struct btrfs_fs_info *fs_info,
struct scrub_block *sblock, int is_metadata,
int have_csum, u8 *csum, u64 generation,
u16 csum_size);
static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
struct scrub_block *sblock,
int is_metadata, int have_csum,
const u8 *csum, u64 generation,
u16 csum_size);
static void scrub_complete_bio_end_io(struct bio *bio, int err);
static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
struct scrub_block *sblock_good,
int force_write);
static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
struct scrub_block *sblock_good,
int page_num, int force_write);
static int scrub_checksum_data(struct scrub_block *sblock);
static int scrub_checksum_tree_block(struct scrub_block *sblock);
static int scrub_checksum_super(struct scrub_block *sblock);
static void scrub_block_get(struct scrub_block *sblock);
static void scrub_block_put(struct scrub_block *sblock);
static int scrub_add_page_to_bio(struct scrub_dev *sdev,
struct scrub_page *spage);
static int scrub_pages(struct scrub_dev *sdev, u64 logical, u64 len,
u64 physical, u64 flags, u64 gen, int mirror_num,
u8 *csum, int force);
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);
static void scrub_bio_end_io_worker(struct btrfs_work *work);
static void scrub_block_complete(struct scrub_block *sblock);
static void scrub_free_csums(struct scrub_dev *sdev)
......@@ -133,23 +182,6 @@ static void scrub_free_csums(struct scrub_dev *sdev)
}
}
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;
......@@ -157,13 +189,23 @@ static noinline_for_stack void scrub_free_dev(struct scrub_dev *sdev)
if (!sdev)
return;
/* this can happen when scrub is cancelled */
if (sdev->curr != -1) {
struct scrub_bio *sbio = sdev->bios[sdev->curr];
for (i = 0; i < sbio->page_count; i++) {
BUG_ON(!sbio->pagev[i]);
BUG_ON(!sbio->pagev[i]->page);
scrub_block_put(sbio->pagev[i]->sblock);
}
bio_put(sbio->bio);
}
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);
}
......@@ -177,11 +219,16 @@ 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;
int pages_per_bio;
pages_per_bio = min_t(int, SCRUB_PAGES_PER_BIO,
bio_get_nr_vecs(dev->bdev));
sdev = kzalloc(sizeof(*sdev), GFP_NOFS);
if (!sdev)
goto nomem;
sdev->dev = dev;
sdev->pages_per_bio = pages_per_bio;
sdev->curr = -1;
for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) {
struct scrub_bio *sbio;
......@@ -192,8 +239,8 @@ struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev)
sbio->index = i;
sbio->sdev = sdev;
sbio->count = 0;
sbio->work.func = scrub_checksum;
sbio->page_count = 0;
sbio->work.func = scrub_bio_end_io_worker;
if (i != SCRUB_BIOS_PER_DEV-1)
sdev->bios[i]->next_free = i + 1;
......@@ -201,7 +248,9 @@ struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev)
sdev->bios[i]->next_free = -1;
}
sdev->first_free = 0;
sdev->curr = -1;
sdev->nodesize = dev->dev_root->nodesize;
sdev->leafsize = dev->dev_root->leafsize;
sdev->sectorsize = dev->dev_root->sectorsize;
atomic_set(&sdev->in_flight, 0);
atomic_set(&sdev->fixup_cnt, 0);
atomic_set(&sdev->cancel_req, 0);
......@@ -292,10 +341,9 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx)
return 0;
}
static void scrub_print_warning(const char *errstr, struct scrub_bio *sbio,
int ix)
static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
{
struct btrfs_device *dev = sbio->sdev->dev;
struct btrfs_device *dev = sblock->sdev->dev;
struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
struct btrfs_path *path;
struct btrfs_key found_key;
......@@ -314,8 +362,9 @@ static void scrub_print_warning(const char *errstr, struct scrub_bio *sbio,
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;
BUG_ON(sblock->page_count < 1);
swarn.sector = (sblock->pagev[0].physical) >> 9;
swarn.logical = sblock->pagev[0].logical;
swarn.errstr = errstr;
swarn.dev = dev;
swarn.msg_bufsize = bufsize;
......@@ -530,9 +579,9 @@ static void scrub_fixup_nodatasum(struct btrfs_work *work)
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);
printk_ratelimited(KERN_ERR
"btrfs: unable to fixup (nodatasum) error at logical %llu on dev %s\n",
(unsigned long long)fixup->logical, sdev->dev->name);
}
btrfs_free_path(path);
......@@ -549,91 +598,168 @@ static void scrub_fixup_nodatasum(struct btrfs_work *work)
}
/*
* 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
* scrub_handle_errored_block gets called when either verification of the
* pages failed or the bio failed to read, e.g. with EIO. In the latter
* case, this function handles all pages in the bio, even though only one
* may be bad.
* The goal of this function is to repair the errored block by using the
* contents of one of the mirrors.
*/
static int scrub_recheck_error(struct scrub_bio *sbio, int ix)
static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
{
struct scrub_dev *sdev = sbio->sdev;
u64 sector = (sbio->physical + ix * PAGE_SIZE) >> 9;
struct scrub_dev *sdev = sblock_to_check->sdev;
struct btrfs_fs_info *fs_info;
u64 length;
u64 logical;
u64 generation;
unsigned int failed_mirror_index;
unsigned int is_metadata;
unsigned int have_csum;
u8 *csum;
struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */
struct scrub_block *sblock_bad;
int ret;
int mirror_index;
int page_num;
int success;
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);
BUG_ON(sblock_to_check->page_count < 1);
fs_info = sdev->dev->dev_root->fs_info;
length = sblock_to_check->page_count * PAGE_SIZE;
logical = sblock_to_check->pagev[0].logical;
generation = sblock_to_check->pagev[0].generation;
BUG_ON(sblock_to_check->pagev[0].mirror_num < 1);
failed_mirror_index = sblock_to_check->pagev[0].mirror_num - 1;
is_metadata = !(sblock_to_check->pagev[0].flags &
BTRFS_EXTENT_FLAG_DATA);
have_csum = sblock_to_check->pagev[0].have_csum;
csum = sblock_to_check->pagev[0].csum;
/*
* read all mirrors one after the other. This includes to
* re-read the extent or metadata block that failed (that was
* the cause that this fixup code is called) another time,
* page by page this time in order to know which pages
* caused I/O errors and which ones are good (for all mirrors).
* It is the goal to handle the situation when more than one
* mirror contains I/O errors, but the errors do not
* overlap, i.e. the data can be repaired by selecting the
* pages from those mirrors without I/O error on the
* particular pages. One example (with blocks >= 2 * PAGE_SIZE)
* would be that mirror #1 has an I/O error on the first page,
* the second page is good, and mirror #2 has an I/O error on
* the second page, but the first page is good.
* Then the first page of the first mirror can be repaired by
* taking the first page of the second mirror, and the
* second page of the second mirror can be repaired by
* copying the contents of the 2nd page of the 1st mirror.
* One more note: if the pages of one mirror contain I/O
* errors, the checksum cannot be verified. In order to get
* the best data for repairing, the first attempt is to find
* a mirror without I/O errors and with a validated checksum.
* Only if this is not possible, the pages are picked from
* mirrors with I/O errors without considering the checksum.
* If the latter is the case, at the end, the checksum of the
* repaired area is verified in order to correctly maintain
* the statistics.
*/
sblocks_for_recheck = kzalloc(BTRFS_MAX_MIRRORS *
sizeof(*sblocks_for_recheck),
GFP_NOFS);
if (!sblocks_for_recheck) {
spin_lock(&sdev->stat_lock);
sdev->stat.malloc_errors++;
sdev->stat.read_errors++;
sdev->stat.uncorrectable_errors++;
spin_unlock(&sdev->stat_lock);
goto out;
}
/* setup the context, map the logical blocks and alloc the pages */
ret = scrub_setup_recheck_block(sdev, &fs_info->mapping_tree, length,
logical, sblocks_for_recheck);
if (ret) {
spin_lock(&sdev->stat_lock);
++sdev->stat.read_errors;
sdev->stat.read_errors++;
sdev->stat.uncorrectable_errors++;
spin_unlock(&sdev->stat_lock);
goto out;
}
BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS);
sblock_bad = sblocks_for_recheck + failed_mirror_index;
scrub_fixup(sbio, ix);
return 1;
}
/* build and submit the bios for the failed mirror, check checksums */
ret = scrub_recheck_block(fs_info, sblock_bad, is_metadata, have_csum,
csum, generation, sdev->csum_size);
if (ret) {
spin_lock(&sdev->stat_lock);
sdev->stat.read_errors++;
sdev->stat.uncorrectable_errors++;
spin_unlock(&sdev->stat_lock);
goto out;
}
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;
if (!sblock_bad->header_error && !sblock_bad->checksum_error &&
sblock_bad->no_io_error_seen) {
/*
* the error disappeared after reading page by page, or
* the area was part of a huge bio and other parts of the
* bio caused I/O errors, or the block layer merged several
* read requests into one and the error is caused by a
* different bio (usually one of the two latter cases is
* the cause)
*/
spin_lock(&sdev->stat_lock);
sdev->stat.unverified_errors++;
spin_unlock(&sdev->stat_lock);
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);
goto out;
}
kunmap_atomic(buffer, KM_USER0);
return ret;
}
if (!sblock_bad->no_io_error_seen) {
spin_lock(&sdev->stat_lock);
sdev->stat.read_errors++;
spin_unlock(&sdev->stat_lock);
if (__ratelimit(&_rs))
scrub_print_warning("i/o error", sblock_to_check);
} else if (sblock_bad->checksum_error) {
spin_lock(&sdev->stat_lock);
sdev->stat.csum_errors++;
spin_unlock(&sdev->stat_lock);
if (__ratelimit(&_rs))
scrub_print_warning("checksum error", sblock_to_check);
} else if (sblock_bad->header_error) {
spin_lock(&sdev->stat_lock);
sdev->stat.verify_errors++;
spin_unlock(&sdev->stat_lock);
if (__ratelimit(&_rs))
scrub_print_warning("checksum/header error",
sblock_to_check);
}
static void scrub_fixup_end_io(struct bio *bio, int err)
{
complete((struct completion *)bio->bi_private);
}
if (sdev->readonly)
goto did_not_correct_error;
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 (!is_metadata && !have_csum) {
struct scrub_fixup_nodatasum *fixup_nodatasum;
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;
/*
* !is_metadata and !have_csum, this means that the data
* might not be COW'ed, that it might be modified
* concurrently. The general strategy to work on the
* commit root does not help in the case when COW is not
* used.
*/
fixup_nodatasum = kzalloc(sizeof(*fixup_nodatasum), GFP_NOFS);
if (!fixup_nodatasum)
goto did_not_correct_error;
fixup_nodatasum->sdev = sdev;
fixup_nodatasum->logical = logical;
fixup_nodatasum->root = fs_info->extent_root;
fixup_nodatasum->mirror_num = failed_mirror_index + 1;
/*
* increment scrubs_running to prevent cancel requests from
* completing as long as a fixup worker is running. we must also
......@@ -648,235 +774,529 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix)
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;
fixup_nodatasum->work.func = scrub_fixup_nodatasum;
btrfs_queue_worker(&fs_info->scrub_workers,
&fixup_nodatasum->work);
goto out;
}
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;
/*
* now build and submit the bios for the other mirrors, check
* checksums
*/
for (mirror_index = 0;
mirror_index < BTRFS_MAX_MIRRORS &&
sblocks_for_recheck[mirror_index].page_count > 0;
mirror_index++) {
if (mirror_index == failed_mirror_index)
continue;
/* build and submit the bios, check checksums */
ret = scrub_recheck_block(fs_info,
sblocks_for_recheck + mirror_index,
is_metadata, have_csum, csum,
generation, sdev->csum_size);
if (ret)
goto did_not_correct_error;
}
if (bbio->num_stripes == 1)
/* there aren't any replicas */
goto uncorrectable;
/*
* first try to pick the mirror which is completely without I/O
* errors and also does not have a checksum error.
* If one is found, and if a checksum is present, the full block
* that is known to contain an error is rewritten. Afterwards
* the block is known to be corrected.
* If a mirror is found which is completely correct, and no
* checksum is present, only those pages are rewritten that had
* an I/O error in the block to be repaired, since it cannot be
* determined, which copy of the other pages is better (and it
* could happen otherwise that a correct page would be
* overwritten by a bad one).
*/
for (mirror_index = 0;
mirror_index < BTRFS_MAX_MIRRORS &&
sblocks_for_recheck[mirror_index].page_count > 0;
mirror_index++) {
struct scrub_block *sblock_other = sblocks_for_recheck +
mirror_index;
if (!sblock_other->header_error &&
!sblock_other->checksum_error &&
sblock_other->no_io_error_seen) {
int force_write = is_metadata || have_csum;
ret = scrub_repair_block_from_good_copy(sblock_bad,
sblock_other,
force_write);
if (0 == ret)
goto corrected_error;
}
}
/*
* first find a good copy
* in case of I/O errors in the area that is supposed to be
* repaired, continue by picking good copies of those pages.
* Select the good pages from mirrors to rewrite bad pages from
* the area to fix. Afterwards verify the checksum of the block
* that is supposed to be repaired. This verification step is
* only done for the purpose of statistic counting and for the
* final scrub report, whether errors remain.
* A perfect algorithm could make use of the checksum and try
* all possible combinations of pages from the different mirrors
* until the checksum verification succeeds. For example, when
* the 2nd page of mirror #1 faces I/O errors, and the 2nd page
* of mirror #2 is readable but the final checksum test fails,
* then the 2nd page of mirror #3 could be tried, whether now
* the final checksum succeedes. But this would be a rare
* exception and is therefore not implemented. At least it is
* avoided that the good copy is overwritten.
* A more useful improvement would be to pick the sectors
* without I/O error based on sector sizes (512 bytes on legacy
* disks) instead of on PAGE_SIZE. Then maybe 512 byte of one
* mirror could be repaired by taking 512 byte of a different
* mirror, even if other 512 byte sectors in the same PAGE_SIZE
* area are unreadable.
*/
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 */
/* can only fix I/O errors from here on */
if (sblock_bad->no_io_error_seen)
goto did_not_correct_error;
success = 1;
for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
struct scrub_page *page_bad = sblock_bad->pagev + page_num;
if (!page_bad->io_error)
continue;
for (mirror_index = 0;
mirror_index < BTRFS_MAX_MIRRORS &&
sblocks_for_recheck[mirror_index].page_count > 0;
mirror_index++) {
struct scrub_block *sblock_other = sblocks_for_recheck +
mirror_index;
struct scrub_page *page_other = sblock_other->pagev +
page_num;
if (!page_other->io_error) {
ret = scrub_repair_page_from_good_copy(
sblock_bad, sblock_other, page_num, 0);
if (0 == ret) {
page_bad->io_error = 0;
break; /* succeeded for this page */
}
}
}
if (scrub_fixup_check(sbio, ix) == 0)
break;
if (page_bad->io_error) {
/* did not find a mirror to copy the page from */
success = 0;
}
}
if (i == bbio->num_stripes)
goto uncorrectable;
if (!sdev->readonly) {
if (success) {
if (is_metadata || have_csum) {
/*
* bi_io_vec[ix].bv_page now contains good data, write it back
* need to verify the checksum now that all
* sectors on disk are repaired (the write
* request for data to be repaired is on its way).
* Just be lazy and use scrub_recheck_block()
* which re-reads the data before the checksum
* is verified, but most likely the data comes out
* of the page cache.
*/
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;
}
ret = scrub_recheck_block(fs_info, sblock_bad,
is_metadata, have_csum, csum,
generation, sdev->csum_size);
if (!ret && !sblock_bad->header_error &&
!sblock_bad->checksum_error &&
sblock_bad->no_io_error_seen)
goto corrected_error;
else
goto did_not_correct_error;
} else {
corrected_error:
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 on dev %s\n",
(unsigned long long)logical, sdev->dev->name);
}
kfree(bbio);
} else {
did_not_correct_error:
spin_lock(&sdev->stat_lock);
++sdev->stat.corrected_errors;
sdev->stat.uncorrectable_errors++;
spin_unlock(&sdev->stat_lock);
printk_ratelimited(KERN_ERR
"btrfs: unable to fixup (regular) error at logical %llu on dev %s\n",
(unsigned long long)logical, sdev->dev->name);
}
printk_ratelimited(KERN_ERR "btrfs: fixed up error at logical %llu\n",
(unsigned long long)logical);
return;
out:
if (sblocks_for_recheck) {
for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS;
mirror_index++) {
struct scrub_block *sblock = sblocks_for_recheck +
mirror_index;
int page_index;
for (page_index = 0; page_index < SCRUB_PAGES_PER_BIO;
page_index++)
if (sblock->pagev[page_index].page)
__free_page(
sblock->pagev[page_index].page);
}
kfree(sblocks_for_recheck);
}
uncorrectable:
return 0;
}
static int scrub_setup_recheck_block(struct scrub_dev *sdev,
struct btrfs_mapping_tree *map_tree,
u64 length, u64 logical,
struct scrub_block *sblocks_for_recheck)
{
int page_index;
int mirror_index;
int ret;
/*
* note: the three members sdev, ref_count and outstanding_pages
* are not used (and not set) in the blocks that are used for
* the recheck procedure
*/
page_index = 0;
while (length > 0) {
u64 sublen = min_t(u64, length, PAGE_SIZE);
u64 mapped_length = sublen;
struct btrfs_bio *bbio = NULL;
/*
* with a length of PAGE_SIZE, each returned stripe
* represents one mirror
*/
ret = btrfs_map_block(map_tree, WRITE, logical, &mapped_length,
&bbio, 0);
if (ret || !bbio || mapped_length < sublen) {
kfree(bbio);
return -EIO;
}
BUG_ON(page_index >= SCRUB_PAGES_PER_BIO);
for (mirror_index = 0; mirror_index < (int)bbio->num_stripes;
mirror_index++) {
struct scrub_block *sblock;
struct scrub_page *page;
if (mirror_index >= BTRFS_MAX_MIRRORS)
continue;
sblock = sblocks_for_recheck + mirror_index;
page = sblock->pagev + page_index;
page->logical = logical;
page->physical = bbio->stripes[mirror_index].physical;
page->bdev = bbio->stripes[mirror_index].dev->bdev;
page->mirror_num = mirror_index + 1;
page->page = alloc_page(GFP_NOFS);
if (!page->page) {
spin_lock(&sdev->stat_lock);
++sdev->stat.uncorrectable_errors;
sdev->stat.malloc_errors++;
spin_unlock(&sdev->stat_lock);
return -ENOMEM;
}
sblock->page_count++;
}
kfree(bbio);
length -= sublen;
logical += sublen;
page_index++;
}
printk_ratelimited(KERN_ERR "btrfs: unable to fixup (regular) error at "
"logical %llu\n", (unsigned long long)logical);
return 0;
}
static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector,
struct page *page)
/*
* this function will check the on disk data for checksum errors, header
* errors and read I/O errors. If any I/O errors happen, the exact pages
* which are errored are marked as being bad. The goal is to enable scrub
* to take those pages that are not errored from all the mirrors so that
* the pages that are errored in the just handled mirror can be repaired.
*/
static int scrub_recheck_block(struct btrfs_fs_info *fs_info,
struct scrub_block *sblock, int is_metadata,
int have_csum, u8 *csum, u64 generation,
u16 csum_size)
{
struct bio *bio = NULL;
int page_num;
sblock->no_io_error_seen = 1;
sblock->header_error = 0;
sblock->checksum_error = 0;
for (page_num = 0; page_num < sblock->page_count; page_num++) {
struct bio *bio;
int ret;
struct scrub_page *page = sblock->pagev + page_num;
DECLARE_COMPLETION_ONSTACK(complete);
BUG_ON(!page->page);
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_bdev = page->bdev;
bio->bi_sector = page->physical >> 9;
bio->bi_end_io = scrub_complete_bio_end_io;
bio->bi_private = &complete;
btrfsic_submit_bio(rw, bio);
ret = bio_add_page(bio, page->page, PAGE_SIZE, 0);
if (PAGE_SIZE != ret) {
bio_put(bio);
return -EIO;
}
btrfsic_submit_bio(READ, bio);
/* this will also unplug the queue */
wait_for_completion(&complete);
ret = !test_bit(BIO_UPTODATE, &bio->bi_flags);
page->io_error = !test_bit(BIO_UPTODATE, &bio->bi_flags);
if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
sblock->no_io_error_seen = 0;
bio_put(bio);
return ret;
}
if (sblock->no_io_error_seen)
scrub_recheck_block_checksum(fs_info, sblock, is_metadata,
have_csum, csum, generation,
csum_size);
return 0;
}
static void scrub_bio_end_io(struct bio *bio, int err)
static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
struct scrub_block *sblock,
int is_metadata, int have_csum,
const u8 *csum, u64 generation,
u16 csum_size)
{
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;
int page_num;
u8 calculated_csum[BTRFS_CSUM_SIZE];
u32 crc = ~(u32)0;
struct btrfs_root *root = fs_info->extent_root;
void *mapped_buffer;
sbio->err = err;
sbio->bio = bio;
BUG_ON(!sblock->pagev[0].page);
if (is_metadata) {
struct btrfs_header *h;
btrfs_queue_worker(&fs_info->scrub_workers, &sbio->work);
mapped_buffer = kmap_atomic(sblock->pagev[0].page, KM_USER0);
h = (struct btrfs_header *)mapped_buffer;
if (sblock->pagev[0].logical != le64_to_cpu(h->bytenr) ||
generation != le64_to_cpu(h->generation) ||
memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE) ||
memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
BTRFS_UUID_SIZE))
sblock->header_error = 1;
csum = h->csum;
} else {
if (!have_csum)
return;
mapped_buffer = kmap_atomic(sblock->pagev[0].page, KM_USER0);
}
for (page_num = 0;;) {
if (page_num == 0 && is_metadata)
crc = btrfs_csum_data(root,
((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE,
crc, PAGE_SIZE - BTRFS_CSUM_SIZE);
else
crc = btrfs_csum_data(root, mapped_buffer, crc,
PAGE_SIZE);
kunmap_atomic(mapped_buffer, KM_USER0);
page_num++;
if (page_num >= sblock->page_count)
break;
BUG_ON(!sblock->pagev[page_num].page);
mapped_buffer = kmap_atomic(sblock->pagev[page_num].page,
KM_USER0);
}
btrfs_csum_final(crc, calculated_csum);
if (memcmp(calculated_csum, csum, csum_size))
sblock->checksum_error = 1;
}
static void scrub_checksum(struct btrfs_work *work)
static void scrub_complete_bio_end_io(struct bio *bio, int err)
{
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;
complete((struct completion *)bio->bi_private);
}
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);
static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
struct scrub_block *sblock_good,
int force_write)
{
int page_num;
int ret = 0;
for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
int ret_sub;
ret_sub = scrub_repair_page_from_good_copy(sblock_bad,
sblock_good,
page_num,
force_write);
if (ret_sub)
ret = ret_sub;
}
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;
return ret;
}
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;
static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
struct scrub_block *sblock_good,
int page_num, int force_write)
{
struct scrub_page *page_bad = sblock_bad->pagev + page_num;
struct scrub_page *page_good = sblock_good->pagev + page_num;
BUG_ON(sblock_bad->pagev[page_num].page == NULL);
BUG_ON(sblock_good->pagev[page_num].page == NULL);
if (force_write || sblock_bad->header_error ||
sblock_bad->checksum_error || page_bad->io_error) {
struct bio *bio;
int ret;
DECLARE_COMPLETION_ONSTACK(complete);
bio = bio_alloc(GFP_NOFS, 1);
bio->bi_bdev = page_bad->bdev;
bio->bi_sector = page_bad->physical >> 9;
bio->bi_end_io = scrub_complete_bio_end_io;
bio->bi_private = &complete;
ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
if (PAGE_SIZE != ret) {
bio_put(bio);
return -EIO;
}
goto out;
btrfsic_submit_bio(WRITE, bio);
/* this will also unplug the queue */
wait_for_completion(&complete);
bio_put(bio);
}
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;
return 0;
}
static void scrub_checksum(struct scrub_block *sblock)
{
u64 flags;
int ret;
BUG_ON(sblock->page_count < 1);
flags = sblock->pagev[0].flags;
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 {
if (flags & BTRFS_EXTENT_FLAG_DATA)
ret = scrub_checksum_data(sblock);
else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
ret = scrub_checksum_tree_block(sblock);
else if (flags & BTRFS_EXTENT_FLAG_SUPER)
(void)scrub_checksum_super(sblock);
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);
if (ret)
scrub_handle_errored_block(sblock);
}
static int scrub_checksum_data(struct scrub_dev *sdev,
struct scrub_page *spag, void *buffer)
static int scrub_checksum_data(struct scrub_block *sblock)
{
struct scrub_dev *sdev = sblock->sdev;
u8 csum[BTRFS_CSUM_SIZE];
u8 *on_disk_csum;
struct page *page;
void *buffer;
u32 crc = ~(u32)0;
int fail = 0;
struct btrfs_root *root = sdev->dev->dev_root;
u64 len;
int index;
if (!spag->have_csum)
BUG_ON(sblock->page_count < 1);
if (!sblock->pagev[0].have_csum)
return 0;
crc = btrfs_csum_data(root, buffer, crc, PAGE_SIZE);
on_disk_csum = sblock->pagev[0].csum;
page = sblock->pagev[0].page;
buffer = kmap_atomic(page, KM_USER0);
len = sdev->sectorsize;
index = 0;
for (;;) {
u64 l = min_t(u64, len, PAGE_SIZE);
crc = btrfs_csum_data(root, buffer, crc, l);
kunmap_atomic(buffer, KM_USER0);
len -= l;
if (len == 0)
break;
index++;
BUG_ON(index >= sblock->page_count);
BUG_ON(!sblock->pagev[index].page);
page = sblock->pagev[index].page;
buffer = kmap_atomic(page, KM_USER0);
}
btrfs_csum_final(crc, csum);
if (memcmp(csum, spag->csum, sdev->csum_size))
if (memcmp(csum, on_disk_csum, sdev->csum_size))
fail = 1;
if (fail) {
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)
static int scrub_checksum_tree_block(struct scrub_block *sblock)
{
struct scrub_dev *sdev = sblock->sdev;
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];
u8 calculated_csum[BTRFS_CSUM_SIZE];
u8 on_disk_csum[BTRFS_CSUM_SIZE];
struct page *page;
void *mapped_buffer;
u64 mapped_size;
void *p;
u32 crc = ~(u32)0;
int fail = 0;
int crc_fail = 0;
u64 len;
int index;
BUG_ON(sblock->page_count < 1);
page = sblock->pagev[0].page;
mapped_buffer = kmap_atomic(page, KM_USER0);
h = (struct btrfs_header *)mapped_buffer;
memcpy(on_disk_csum, h->csum, sdev->csum_size);
/*
* 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))
if (sblock->pagev[0].logical != le64_to_cpu(h->bytenr))
++fail;
if (spag->generation != le64_to_cpu(h->generation))
if (sblock->pagev[0].generation != le64_to_cpu(h->generation))
++fail;
if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
......@@ -886,51 +1306,99 @@ static int scrub_checksum_tree_block(struct scrub_dev *sdev,
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))
BUG_ON(sdev->nodesize != sdev->leafsize);
len = sdev->nodesize - BTRFS_CSUM_SIZE;
mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
index = 0;
for (;;) {
u64 l = min_t(u64, len, mapped_size);
crc = btrfs_csum_data(root, p, crc, l);
kunmap_atomic(mapped_buffer, KM_USER0);
len -= l;
if (len == 0)
break;
index++;
BUG_ON(index >= sblock->page_count);
BUG_ON(!sblock->pagev[index].page);
page = sblock->pagev[index].page;
mapped_buffer = kmap_atomic(page, KM_USER0);
mapped_size = PAGE_SIZE;
p = mapped_buffer;
}
btrfs_csum_final(crc, calculated_csum);
if (memcmp(calculated_csum, on_disk_csum, sdev->csum_size))
++crc_fail;
if (crc_fail || 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)
static int scrub_checksum_super(struct scrub_block *sblock)
{
struct btrfs_super_block *s;
u64 logical;
struct scrub_dev *sdev = sbio->sdev;
struct scrub_dev *sdev = sblock->sdev;
struct btrfs_root *root = sdev->dev->dev_root;
struct btrfs_fs_info *fs_info = root->fs_info;
u8 csum[BTRFS_CSUM_SIZE];
u8 calculated_csum[BTRFS_CSUM_SIZE];
u8 on_disk_csum[BTRFS_CSUM_SIZE];
struct page *page;
void *mapped_buffer;
u64 mapped_size;
void *p;
u32 crc = ~(u32)0;
int fail = 0;
u64 len;
int index;
s = (struct btrfs_super_block *)buffer;
logical = sbio->logical;
BUG_ON(sblock->page_count < 1);
page = sblock->pagev[0].page;
mapped_buffer = kmap_atomic(page, KM_USER0);
s = (struct btrfs_super_block *)mapped_buffer;
memcpy(on_disk_csum, s->csum, sdev->csum_size);
if (logical != le64_to_cpu(s->bytenr))
if (sblock->pagev[0].logical != le64_to_cpu(s->bytenr))
++fail;
if (sbio->spag[0].generation != le64_to_cpu(s->generation))
if (sblock->pagev[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))
len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE;
mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
index = 0;
for (;;) {
u64 l = min_t(u64, len, mapped_size);
crc = btrfs_csum_data(root, p, crc, l);
kunmap_atomic(mapped_buffer, KM_USER0);
len -= l;
if (len == 0)
break;
index++;
BUG_ON(index >= sblock->page_count);
BUG_ON(!sblock->pagev[index].page);
page = sblock->pagev[index].page;
mapped_buffer = kmap_atomic(page, KM_USER0);
mapped_size = PAGE_SIZE;
p = mapped_buffer;
}
btrfs_csum_final(crc, calculated_csum);
if (memcmp(calculated_csum, on_disk_csum, sdev->csum_size))
++fail;
if (fail) {
......@@ -947,6 +1415,23 @@ static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer)
return fail;
}
static void scrub_block_get(struct scrub_block *sblock)
{
atomic_inc(&sblock->ref_count);
}
static void scrub_block_put(struct scrub_block *sblock)
{
if (atomic_dec_and_test(&sblock->ref_count)) {
int i;
for (i = 0; i < sblock->page_count; i++)
if (sblock->pagev[i].page)
__free_page(sblock->pagev[i].page);
kfree(sblock);
}
}
static void scrub_submit(struct scrub_dev *sdev)
{
struct scrub_bio *sbio;
......@@ -955,19 +1440,17 @@ static void scrub_submit(struct scrub_dev *sdev)
return;
sbio = sdev->bios[sdev->curr];
sbio->err = 0;
sdev->curr = -1;
atomic_inc(&sdev->in_flight);
btrfsic_submit_bio(READ, sbio->bio);
}
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)
static int scrub_add_page_to_bio(struct scrub_dev *sdev,
struct scrub_page *spage)
{
struct scrub_block *sblock = spage->sblock;
struct scrub_bio *sbio;
struct page *page;
int ret;
again:
......@@ -980,7 +1463,7 @@ static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len,
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;
sdev->bios[sdev->curr]->page_count = 0;
spin_unlock(&sdev->list_lock);
} else {
spin_unlock(&sdev->list_lock);
......@@ -988,53 +1471,200 @@ static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len,
}
}
sbio = sdev->bios[sdev->curr];
if (sbio->count == 0) {
if (sbio->page_count == 0) {
struct bio *bio;
sbio->physical = physical;
sbio->logical = logical;
bio = bio_alloc(GFP_NOFS, SCRUB_PAGES_PER_BIO);
sbio->physical = spage->physical;
sbio->logical = spage->logical;
bio = sbio->bio;
if (!bio) {
bio = bio_alloc(GFP_NOFS, sdev->pages_per_bio);
if (!bio)
return -ENOMEM;
sbio->bio = bio;
}
bio->bi_private = sbio;
bio->bi_end_io = scrub_bio_end_io;
bio->bi_bdev = sdev->dev->bdev;
bio->bi_sector = sbio->physical >> 9;
bio->bi_sector = spage->physical >> 9;
sbio->err = 0;
sbio->bio = bio;
} else if (sbio->physical + sbio->count * PAGE_SIZE != physical ||
sbio->logical + sbio->count * PAGE_SIZE != logical) {
} else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
spage->physical ||
sbio->logical + sbio->page_count * PAGE_SIZE !=
spage->logical) {
scrub_submit(sdev);
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);
sbio->pagev[sbio->page_count] = spage;
ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
if (ret != PAGE_SIZE) {
if (sbio->page_count < 1) {
bio_put(sbio->bio);
sbio->bio = NULL;
return -EIO;
}
scrub_submit(sdev);
goto again;
}
scrub_block_get(sblock); /* one for the added page */
atomic_inc(&sblock->outstanding_pages);
sbio->page_count++;
if (sbio->page_count == sdev->pages_per_bio)
scrub_submit(sdev);
return 0;
}
static int scrub_pages(struct scrub_dev *sdev, u64 logical, u64 len,
u64 physical, u64 flags, u64 gen, int mirror_num,
u8 *csum, int force)
{
struct scrub_block *sblock;
int index;
sblock = kzalloc(sizeof(*sblock), GFP_NOFS);
if (!sblock) {
spin_lock(&sdev->stat_lock);
sdev->stat.malloc_errors++;
spin_unlock(&sdev->stat_lock);
return -ENOMEM;
}
/* one ref inside this function, plus one for each page later on */
atomic_set(&sblock->ref_count, 1);
sblock->sdev = sdev;
sblock->no_io_error_seen = 1;
for (index = 0; len > 0; index++) {
struct scrub_page *spage = sblock->pagev + index;
u64 l = min_t(u64, len, PAGE_SIZE);
BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
spage->page = alloc_page(GFP_NOFS);
if (!spage->page) {
spin_lock(&sdev->stat_lock);
sdev->stat.malloc_errors++;
spin_unlock(&sdev->stat_lock);
while (index > 0) {
index--;
__free_page(sblock->pagev[index].page);
}
kfree(sblock);
return -ENOMEM;
}
spage->sblock = sblock;
spage->bdev = sdev->dev->bdev;
spage->flags = flags;
spage->generation = gen;
spage->logical = logical;
spage->physical = physical;
spage->mirror_num = mirror_num;
if (csum) {
sbio->spag[sbio->count].have_csum = 1;
memcpy(sbio->spag[sbio->count].csum, csum, sdev->csum_size);
spage->have_csum = 1;
memcpy(spage->csum, csum, sdev->csum_size);
} else {
spage->have_csum = 0;
}
sblock->page_count++;
len -= l;
logical += l;
physical += l;
}
BUG_ON(sblock->page_count == 0);
for (index = 0; index < sblock->page_count; index++) {
struct scrub_page *spage = sblock->pagev + index;
int ret;
ret = scrub_add_page_to_bio(sdev, spage);
if (ret) {
scrub_block_put(sblock);
return ret;
}
}
++sbio->count;
if (sbio->count == SCRUB_PAGES_PER_BIO || force)
if (force)
scrub_submit(sdev);
/* last one frees, either here or in bio completion for last page */
scrub_block_put(sblock);
return 0;
}
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_bio_end_io_worker(struct btrfs_work *work)
{
struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
struct scrub_dev *sdev = sbio->sdev;
int i;
BUG_ON(sbio->page_count > SCRUB_PAGES_PER_BIO);
if (sbio->err) {
for (i = 0; i < sbio->page_count; i++) {
struct scrub_page *spage = sbio->pagev[i];
spage->io_error = 1;
spage->sblock->no_io_error_seen = 0;
}
}
/* now complete the scrub_block items that have all pages completed */
for (i = 0; i < sbio->page_count; i++) {
struct scrub_page *spage = sbio->pagev[i];
struct scrub_block *sblock = spage->sblock;
if (atomic_dec_and_test(&sblock->outstanding_pages))
scrub_block_complete(sblock);
scrub_block_put(sblock);
}
if (sbio->err) {
/* what is this good for??? */
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->page_count; i++) {
struct bio_vec *bi;
bi = &sbio->bio->bi_io_vec[i];
bi->bv_offset = 0;
bi->bv_len = PAGE_SIZE;
}
}
bio_put(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 void scrub_block_complete(struct scrub_block *sblock)
{
if (!sblock->no_io_error_seen)
scrub_handle_errored_block(sblock);
else
scrub_checksum(sblock);
}
static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len,
u8 *csum)
{
......@@ -1042,7 +1672,6 @@ static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len,
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,
......@@ -1060,7 +1689,7 @@ static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len,
if (!sum)
return 0;
num_sectors = sum->len / sectorsize;
num_sectors = sum->len / sdev->sectorsize;
for (i = 0; i < num_sectors; ++i) {
if (sum->sums[i].bytenr == logical) {
memcpy(csum, &sum->sums[i].sum, sdev->csum_size);
......@@ -1081,9 +1710,28 @@ static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len,
{
int ret;
u8 csum[BTRFS_CSUM_SIZE];
u32 blocksize;
if (flags & BTRFS_EXTENT_FLAG_DATA) {
blocksize = sdev->sectorsize;
spin_lock(&sdev->stat_lock);
sdev->stat.data_extents_scrubbed++;
sdev->stat.data_bytes_scrubbed += len;
spin_unlock(&sdev->stat_lock);
} else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
BUG_ON(sdev->nodesize != sdev->leafsize);
blocksize = sdev->nodesize;
spin_lock(&sdev->stat_lock);
sdev->stat.tree_extents_scrubbed++;
sdev->stat.tree_bytes_scrubbed += len;
spin_unlock(&sdev->stat_lock);
} else {
blocksize = sdev->sectorsize;
BUG_ON(1);
}
while (len) {
u64 l = min_t(u64, len, PAGE_SIZE);
u64 l = min_t(u64, len, blocksize);
int have_csum = 0;
if (flags & BTRFS_EXTENT_FLAG_DATA) {
......@@ -1092,7 +1740,7 @@ static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len,
if (have_csum == 0)
++sdev->stat.no_csum;
}
ret = scrub_page(sdev, logical, l, physical, flags, gen,
ret = scrub_pages(sdev, logical, l, physical, flags, gen,
mirror_num, have_csum ? csum : NULL, 0);
if (ret)
return ret;
......@@ -1158,6 +1806,11 @@ static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev,
if (!path)
return -ENOMEM;
/*
* work on commit root. The related disk blocks are static as
* long as COW is applied. This means, it is save to rewrite
* them to repair disk errors without any race conditions
*/
path->search_commit_root = 1;
path->skip_locking = 1;
......@@ -1511,7 +2164,7 @@ static noinline_for_stack int scrub_supers(struct scrub_dev *sdev)
if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
break;
ret = scrub_page(sdev, bytenr, PAGE_SIZE, bytenr,
ret = scrub_pages(sdev, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
BTRFS_EXTENT_FLAG_SUPER, gen, i, NULL, 1);
if (ret)
return ret;
......@@ -1571,10 +2224,30 @@ int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end,
/*
* 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");
if (root->nodesize != root->leafsize) {
printk(KERN_ERR
"btrfs_scrub: size assumption nodesize == leafsize (%d == %d) fails\n",
root->nodesize, root->leafsize);
return -EINVAL;
}
if (root->nodesize > BTRFS_STRIPE_LEN) {
/*
* in this case scrub is unable to calculate the checksum
* the way scrub is implemented. Do not handle this
* situation at all because it won't ever happen.
*/
printk(KERN_ERR
"btrfs_scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails\n",
root->nodesize, BTRFS_STRIPE_LEN);
return -EINVAL;
}
if (root->sectorsize != PAGE_SIZE) {
/* not supported for data w/o checksums */
printk(KERN_ERR
"btrfs_scrub: size assumption sectorsize != PAGE_SIZE (%d != %lld) fails\n",
root->sectorsize, (unsigned long long)PAGE_SIZE);
return -EINVAL;
}
......
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