@@ -60,7 +60,6 @@ typedef struct work_struct scrub_work_t;
struct scrub_bio;
struct scrub_page;
struct scrub_dev;
-struct scrub_fixup;
static void scrub_bio_end_io(struct bio *bio, int err);
static void scrub_checksum(scrub_work_t *work);
static int scrub_checksum_data(struct scrub_dev *sdev,
@@ -69,9 +68,11 @@ 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 void scrub_recheck_end_io(struct bio *bio, int err);
-static void scrub_fixup_worker(scrub_work_t *work);
-static void scrub_fixup(struct scrub_fixup *fixup);
+static int scrub_fixup_check(struct scrub_bio *sbio, int ix);
+static void scrub_fixup_end_io(struct bio *bio, int err);
+static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector,
+ struct page *page);
+static void scrub_fixup(struct scrub_bio *sbio, int ix);
#define SCRUB_PAGES_PER_BIO 16 /* 64k per bio */
#define SCRUB_BIOS_PER_DEV 16 /* 1 MB per device in flight */
@@ -115,17 +116,6 @@ struct scrub_dev {
spinlock_t stat_lock;
};
-struct scrub_fixup {
- struct scrub_dev *sdev;
- struct bio *bio;
- u64 logical;
- u64 physical;
- struct scrub_page spag;
- scrub_work_t work;
- int err;
- int recheck;
-};
-
static void scrub_free_csums(struct scrub_dev *sdev)
{
while(!list_empty(&sdev->csum_list)) {
@@ -250,108 +240,34 @@ nomem:
*/
static void scrub_recheck_error(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 bio *bio = NULL;
- struct page *page = NULL;
- struct scrub_fixup *fixup = NULL;
- int ret;
-
- /*
- * while we're in here we do not want the transaction to commit.
- * To prevent it, we increment scrubs_running. scrub_pause will
- * have to wait until we're finished
- * we can safely increment scrubs_running here, because we're
- * in the context of the original bio which is still marked in_flight
- */
- atomic_inc(&fs_info->scrubs_running);
-
- fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
- if (!fixup)
- goto malloc_error;
-
- fixup->logical = sbio->logical + ix * PAGE_SIZE;
- fixup->physical = sbio->physical + ix * PAGE_SIZE;
- fixup->spag = sbio->spag[ix];
- fixup->sdev = sdev;
-
- bio = bio_alloc(GFP_NOFS, 1);
- if (!bio)
- goto malloc_error;
- bio->bi_private = fixup;
- bio->bi_size = 0;
- bio->bi_bdev = sdev->dev->bdev;
- fixup->bio = bio;
- fixup->recheck = 0;
-
- page = alloc_page(GFP_NOFS);
- if (!page)
- goto malloc_error;
-
- ret = bio_add_page(bio, page, PAGE_SIZE, 0);
- if (!ret)
- goto malloc_error;
-
- if (!sbio->err) {
- /*
- * shorter path: just a checksum error, go ahead and correct it
- */
- scrub_fixup_worker(&fixup->work);
- return;
+ if (sbio->err) {
+ if (scrub_fixup_io(READ, sbio->sdev->dev->bdev,
+ (sbio->physical + ix * PAGE_SIZE) >> 9,
+ sbio->bio->bi_io_vec[ix].bv_page) == 0) {
+ if (scrub_fixup_check(sbio, ix) == 0)
+ return;
+ }
}
- /*
- * an I/O-error occured for one of the blocks in the bio, not
- * necessarily for this one, so first try to read it separately
- */
- SCRUB_INIT_WORK(&fixup->work, scrub_fixup_worker);
- fixup->recheck = 1;
- bio->bi_end_io = scrub_recheck_end_io;
- bio->bi_sector = fixup->physical >> 9;
- bio->bi_bdev = sdev->dev->bdev;
- submit_bio(0, bio);
-
- return;
-
-malloc_error:
- if (bio)
- bio_put(bio);
- if (page)
- __free_page(page);
- if (fixup)
- kfree(fixup);
- spin_lock(&sdev->stat_lock);
- ++sdev->stat.malloc_errors;
- spin_unlock(&sdev->stat_lock);
- atomic_dec(&fs_info->scrubs_running);
- wake_up(&fs_info->scrub_pause_wait);
-}
-
-static void scrub_recheck_end_io(struct bio *bio, int err)
-{
- struct scrub_fixup *fixup = bio->bi_private;
- struct btrfs_fs_info *fs_info = fixup->sdev->dev->dev_root->fs_info;
-
- fixup->err = err;
- SCRUB_QUEUE_WORK(fs_info->scrub_workers, &fixup->work);
+ scrub_fixup(sbio, ix);
}
-static int scrub_fixup_check(struct scrub_fixup *fixup)
+static int scrub_fixup_check(struct scrub_bio *sbio, int ix)
{
int ret = 1;
struct page *page;
void *buffer;
- u64 flags = fixup->spag.flags;
+ u64 flags = sbio->spag[ix].flags;
- page = fixup->bio->bi_io_vec[0].bv_page;
+ 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(fixup->sdev,
- &fixup->spag, buffer);
+ ret = scrub_checksum_data(sbio->sdev,
+ sbio->spag + ix, buffer);
} else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
- ret = scrub_checksum_tree_block(fixup->sdev,
- &fixup->spag,
- fixup->logical,
+ ret = scrub_checksum_tree_block(sbio->sdev,
+ sbio->spag + ix,
+ sbio->logical + ix * PAGE_SIZE,
buffer);
} else {
WARN_ON(1);
@@ -361,51 +277,25 @@ static int scrub_fixup_check(struct scrub_fixup *fixup)
return ret;
}
-static void scrub_fixup_worker(scrub_work_t *work)
-{
- struct scrub_fixup *fixup;
- struct btrfs_fs_info *fs_info;
- u64 flags;
- int ret = 1;
-
- fixup = container_of(work, struct scrub_fixup, work);
- fs_info = fixup->sdev->dev->dev_root->fs_info;
- flags = fixup->spag.flags;
-
- if (fixup->recheck && fixup->err == 0)
- ret = scrub_fixup_check(fixup);
-
- if (ret || fixup->err)
- scrub_fixup(fixup);
-
- __free_page(fixup->bio->bi_io_vec[0].bv_page);
- bio_put(fixup->bio);
-
- atomic_dec(&fs_info->scrubs_running);
- wake_up(&fs_info->scrub_pause_wait);
-
- kfree(fixup);
-}
-
static void scrub_fixup_end_io(struct bio *bio, int err)
{
complete((struct completion *)bio->bi_private);
}
-static void scrub_fixup(struct scrub_fixup *fixup)
+static void scrub_fixup(struct scrub_bio *sbio, int ix)
{
- struct scrub_dev *sdev = fixup->sdev;
+ 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_multi_bio *multi = NULL;
- struct bio *bio = fixup->bio;
+ u64 logical = sbio->logical + ix * PAGE_SIZE;
u64 length;
int i;
int ret;
DECLARE_COMPLETION_ONSTACK(complete);
- if ((fixup->spag.flags & BTRFS_EXTENT_FLAG_DATA) &&
- (fixup->spag.have_csum == 0)) {
+ if ((sbio->spag[ix].flags & BTRFS_EXTENT_FLAG_DATA) &&
+ (sbio->spag[ix].have_csum == 0)) {
/*
* nodatasum, don't try to fix anything
* FIXME: we can do better, open the inode and trigger a
@@ -415,71 +305,49 @@ static void scrub_fixup(struct scrub_fixup *fixup)
}
length = PAGE_SIZE;
- ret = btrfs_map_block(map_tree, REQ_WRITE, fixup->logical, &length,
+ ret = btrfs_map_block(map_tree, REQ_WRITE, logical, &length,
&multi, 0);
if (ret || !multi || length < PAGE_SIZE) {
printk(KERN_ERR
"scrub_fixup: btrfs_map_block failed us for %llu\n",
- (unsigned long long)fixup->logical);
+ (unsigned long long)logical);
WARN_ON(1);
return;
}
- if (multi->num_stripes == 1) {
+ if (multi->num_stripes == 1)
/* there aren't any replicas */
goto uncorrectable;
- }
/*
* first find a good copy
*/
for (i = 0; i < multi->num_stripes; ++i) {
- if (i == fixup->spag.mirror_num)
+ if (i == sbio->spag[ix].mirror_num)
continue;
- bio->bi_sector = multi->stripes[i].physical >> 9;
- bio->bi_bdev = multi->stripes[i].dev->bdev;
- bio->bi_size = PAGE_SIZE;
- bio->bi_next = NULL;
- bio->bi_flags |= 1 << BIO_UPTODATE;
- bio->bi_comp_cpu = -1;
- bio->bi_end_io = scrub_fixup_end_io;
- bio->bi_private = &complete;
-
- submit_bio(0, bio);
-
- wait_for_completion(&complete);
-
- if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
+ if (scrub_fixup_io(READ, multi->stripes[i].dev->bdev,
+ multi->stripes[i].physical >> 9,
+ sbio->bio->bi_io_vec[ix].bv_page)) {
/* I/O-error, this is not a good copy */
continue;
+ }
- ret = scrub_fixup_check(fixup);
- if (ret == 0)
+ if (scrub_fixup_check(sbio, ix) == 0)
break;
}
if (i == multi->num_stripes)
goto uncorrectable;
/*
- * the bio now contains good data, write it back
+ * bi_io_vec[ix].bv_page now contains good data, write it back
*/
- bio->bi_sector = fixup->physical >> 9;
- bio->bi_bdev = sdev->dev->bdev;
- bio->bi_size = PAGE_SIZE;
- bio->bi_next = NULL;
- bio->bi_flags |= 1 << BIO_UPTODATE;
- bio->bi_comp_cpu = -1;
- bio->bi_end_io = scrub_fixup_end_io;
- bio->bi_private = &complete;
-
- submit_bio(REQ_WRITE, bio);
-
- wait_for_completion(&complete);
-
- if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
+ if (scrub_fixup_io(WRITE, sdev->dev->bdev,
+ (sbio->physical + ix * PAGE_SIZE) >> 9,
+ sbio->bio->bi_io_vec[ix].bv_page)) {
/* I/O-error, writeback failed, give up */
goto uncorrectable;
+ }
kfree(multi);
spin_lock(&sdev->stat_lock);
@@ -488,7 +356,7 @@ static void scrub_fixup(struct scrub_fixup *fixup)
if (printk_ratelimit())
printk(KERN_ERR "btrfs: fixed up at %llu\n",
- (unsigned long long)fixup->logical);
+ (unsigned long long)logical);
return;
uncorrectable:
@@ -499,7 +367,32 @@ uncorrectable:
if (printk_ratelimit())
printk(KERN_ERR "btrfs: unable to fixup at %llu\n",
- (unsigned long long)fixup->logical);
+ (unsigned long long)logical);
+}
+
+static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector,
+ struct page *page)
+{
+ struct bio *bio = NULL;
+ int ret;
+ DECLARE_COMPLETION_ONSTACK(complete);
+
+ /* we are going to wait on this IO */
+ rw |= REQ_SYNC | REQ_UNPLUG;
+
+ bio = bio_alloc(GFP_NOFS, 1);
+ bio->bi_bdev = bdev;
+ bio->bi_sector = sector;
+ bio_add_page(bio, page, PAGE_SIZE, 0);
+ bio->bi_end_io = scrub_fixup_end_io;
+ bio->bi_private = &complete;
+ submit_bio(rw, bio);
+
+ wait_for_completion(&complete);
+
+ ret = !test_bit(BIO_UPTODATE, &bio->bi_flags);
+ bio_put(bio);
+ return ret;
}
static void scrub_bio_end_io(struct bio *bio, int err)
Fixups are already sync for csum failures, this patch makes them sync for EIO case as well. Fixups are now sharing pages with the parent sbio - instead of allocating a separate page to do a fixup we grab the page from the sbio buffer. Fixup bios are no longer reused. struct fixup is no longer needed, instead pass [sbio pointer, index]. Originally this was added to look at the possibility of sharing the code between drive swap and scrub, but it actually fixes a serious bug in scrub code where errors that could be corrected were ignored and reported as uncorrectable. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> --- fs/btrfs/scrub.c | 241 +++++++++++++++--------------------------------------- 1 files changed, 67 insertions(+), 174 deletions(-)