diff options
Diffstat (limited to 'fs/btrfs/raid56.c')
| -rw-r--r-- | fs/btrfs/raid56.c | 763 |
1 files changed, 687 insertions, 76 deletions
diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 6a41631..8ab2a17 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -58,9 +58,23 @@ */ #define RBIO_CACHE_READY_BIT 3 +/* + * bbio and raid_map is managed by the caller, so we shouldn't free + * them here. And besides that, all rbios with this flag should not + * be cached, because we need raid_map to check the rbios' stripe + * is the same or not, but it is very likely that the caller has + * free raid_map, so don't cache those rbios. + */ +#define RBIO_HOLD_BBIO_MAP_BIT 4 #define RBIO_CACHE_SIZE 1024 +enum btrfs_rbio_ops { + BTRFS_RBIO_WRITE = 0, + BTRFS_RBIO_READ_REBUILD = 1, + BTRFS_RBIO_PARITY_SCRUB = 2, +}; + struct btrfs_raid_bio { struct btrfs_fs_info *fs_info; struct btrfs_bio *bbio; @@ -117,13 +131,16 @@ struct btrfs_raid_bio { /* number of data stripes (no p/q) */ int nr_data; + int real_stripes; + + int stripe_npages; /* * set if we're doing a parity rebuild * for a read from higher up, which is handled * differently from a parity rebuild as part of * rmw */ - int read_rebuild; + enum btrfs_rbio_ops operation; /* first bad stripe */ int faila; @@ -131,6 +148,7 @@ struct btrfs_raid_bio { /* second bad stripe (for raid6 use) */ int failb; + int scrubp; /* * number of pages needed to represent the full * stripe @@ -144,8 +162,13 @@ struct btrfs_raid_bio { */ int bio_list_bytes; + int generic_bio_cnt; + atomic_t refs; + atomic_t stripes_pending; + + atomic_t error; /* * these are two arrays of pointers. We allocate the * rbio big enough to hold them both and setup their @@ -162,6 +185,11 @@ struct btrfs_raid_bio { * here for faster lookup */ struct page **bio_pages; + + /* + * bitmap to record which horizontal stripe has data + */ + unsigned long *dbitmap; }; static int __raid56_parity_recover(struct btrfs_raid_bio *rbio); @@ -176,6 +204,10 @@ static void __free_raid_bio(struct btrfs_raid_bio *rbio); static void index_rbio_pages(struct btrfs_raid_bio *rbio); static int alloc_rbio_pages(struct btrfs_raid_bio *rbio); +static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio, + int need_check); +static void async_scrub_parity(struct btrfs_raid_bio *rbio); + /* * the stripe hash table is used for locking, and to collect * bios in hopes of making a full stripe @@ -324,6 +356,7 @@ static void merge_rbio(struct btrfs_raid_bio *dest, { bio_list_merge(&dest->bio_list, &victim->bio_list); dest->bio_list_bytes += victim->bio_list_bytes; + dest->generic_bio_cnt += victim->generic_bio_cnt; bio_list_init(&victim->bio_list); } @@ -577,11 +610,20 @@ static int rbio_can_merge(struct btrfs_raid_bio *last, cur->raid_map[0]) return 0; - /* reads can't merge with writes */ - if (last->read_rebuild != - cur->read_rebuild) { + /* we can't merge with different operations */ + if (last->operation != cur->operation) + return 0; + /* + * We've need read the full stripe from the drive. + * check and repair the parity and write the new results. + * + * We're not allowed to add any new bios to the + * bio list here, anyone else that wants to + * change this stripe needs to do their own rmw. + */ + if (last->operation == BTRFS_RBIO_PARITY_SCRUB || + cur->operation == BTRFS_RBIO_PARITY_SCRUB) return 0; - } return 1; } @@ -601,7 +643,7 @@ static struct page *rbio_pstripe_page(struct btrfs_raid_bio *rbio, int index) */ static struct page *rbio_qstripe_page(struct btrfs_raid_bio *rbio, int index) { - if (rbio->nr_data + 1 == rbio->bbio->num_stripes) + if (rbio->nr_data + 1 == rbio->real_stripes) return NULL; index += ((rbio->nr_data + 1) * rbio->stripe_len) >> @@ -772,11 +814,14 @@ static noinline void unlock_stripe(struct btrfs_raid_bio *rbio) spin_unlock(&rbio->bio_list_lock); spin_unlock_irqrestore(&h->lock, flags); - if (next->read_rebuild) + if (next->operation == BTRFS_RBIO_READ_REBUILD) async_read_rebuild(next); - else { + else if (next->operation == BTRFS_RBIO_WRITE) { steal_rbio(rbio, next); async_rmw_stripe(next); + } else if (next->operation == BTRFS_RBIO_PARITY_SCRUB) { + steal_rbio(rbio, next); + async_scrub_parity(next); } goto done_nolock; @@ -796,6 +841,21 @@ done_nolock: remove_rbio_from_cache(rbio); } +static inline void +__free_bbio_and_raid_map(struct btrfs_bio *bbio, u64 *raid_map, int need) +{ + if (need) { + kfree(raid_map); + kfree(bbio); + } +} + +static inline void free_bbio_and_raid_map(struct btrfs_raid_bio *rbio) +{ + __free_bbio_and_raid_map(rbio->bbio, rbio->raid_map, + !test_bit(RBIO_HOLD_BBIO_MAP_BIT, &rbio->flags)); +} + static void __free_raid_bio(struct btrfs_raid_bio *rbio) { int i; @@ -814,8 +874,9 @@ static void __free_raid_bio(struct btrfs_raid_bio *rbio) rbio->stripe_pages[i] = NULL; } } - kfree(rbio->raid_map); - kfree(rbio->bbio); + + free_bbio_and_raid_map(rbio); + kfree(rbio); } @@ -833,6 +894,10 @@ static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, int err, int uptodate) { struct bio *cur = bio_list_get(&rbio->bio_list); struct bio *next; + + if (rbio->generic_bio_cnt) + btrfs_bio_counter_sub(rbio->fs_info, rbio->generic_bio_cnt); + free_raid_bio(rbio); while (cur) { @@ -858,13 +923,13 @@ static void raid_write_end_io(struct bio *bio, int err) bio_put(bio); - if (!atomic_dec_and_test(&rbio->bbio->stripes_pending)) + if (!atomic_dec_and_test(&rbio->stripes_pending)) return; err = 0; /* OK, we have read all the stripes we need to. */ - if (atomic_read(&rbio->bbio->error) > rbio->bbio->max_errors) + if (atomic_read(&rbio->error) > rbio->bbio->max_errors) err = -EIO; rbio_orig_end_io(rbio, err, 0); @@ -925,16 +990,16 @@ static struct btrfs_raid_bio *alloc_rbio(struct btrfs_root *root, { struct btrfs_raid_bio *rbio; int nr_data = 0; - int num_pages = rbio_nr_pages(stripe_len, bbio->num_stripes); + int real_stripes = bbio->num_stripes - bbio->num_tgtdevs; + int num_pages = rbio_nr_pages(stripe_len, real_stripes); + int stripe_npages = DIV_ROUND_UP(stripe_len, PAGE_SIZE); void *p; - rbio = kzalloc(sizeof(*rbio) + num_pages * sizeof(struct page *) * 2, + rbio = kzalloc(sizeof(*rbio) + num_pages * sizeof(struct page *) * 2 + + DIV_ROUND_UP(stripe_npages, BITS_PER_LONG / 8), GFP_NOFS); - if (!rbio) { - kfree(raid_map); - kfree(bbio); + if (!rbio) return ERR_PTR(-ENOMEM); - } bio_list_init(&rbio->bio_list); INIT_LIST_HEAD(&rbio->plug_list); @@ -946,9 +1011,13 @@ static struct btrfs_raid_bio *alloc_rbio(struct btrfs_root *root, rbio->fs_info = root->fs_info; rbio->stripe_len = stripe_len; rbio->nr_pages = num_pages; + rbio->real_stripes = real_stripes; + rbio->stripe_npages = stripe_npages; rbio->faila = -1; rbio->failb = -1; atomic_set(&rbio->refs, 1); + atomic_set(&rbio->error, 0); + atomic_set(&rbio->stripes_pending, 0); /* * the stripe_pages and bio_pages array point to the extra @@ -957,11 +1026,12 @@ static struct btrfs_raid_bio *alloc_rbio(struct btrfs_root *root, p = rbio + 1; rbio->stripe_pages = p; rbio->bio_pages = p + sizeof(struct page *) * num_pages; + rbio->dbitmap = p + sizeof(struct page *) * num_pages * 2; - if (raid_map[bbio->num_stripes - 1] == RAID6_Q_STRIPE) - nr_data = bbio->num_stripes - 2; + if (raid_map[real_stripes - 1] == RAID6_Q_STRIPE) + nr_data = real_stripes - 2; else - nr_data = bbio->num_stripes - 1; + nr_data = real_stripes - 1; rbio->nr_data = nr_data; return rbio; @@ -1073,7 +1143,7 @@ static int rbio_add_io_page(struct btrfs_raid_bio *rbio, static void validate_rbio_for_rmw(struct btrfs_raid_bio *rbio) { if (rbio->faila >= 0 || rbio->failb >= 0) { - BUG_ON(rbio->faila == rbio->bbio->num_stripes - 1); + BUG_ON(rbio->faila == rbio->real_stripes - 1); __raid56_parity_recover(rbio); } else { finish_rmw(rbio); @@ -1134,7 +1204,7 @@ static void index_rbio_pages(struct btrfs_raid_bio *rbio) static noinline void finish_rmw(struct btrfs_raid_bio *rbio) { struct btrfs_bio *bbio = rbio->bbio; - void *pointers[bbio->num_stripes]; + void *pointers[rbio->real_stripes]; int stripe_len = rbio->stripe_len; int nr_data = rbio->nr_data; int stripe; @@ -1148,11 +1218,11 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio) bio_list_init(&bio_list); - if (bbio->num_stripes - rbio->nr_data == 1) { - p_stripe = bbio->num_stripes - 1; - } else if (bbio->num_stripes - rbio->nr_data == 2) { - p_stripe = bbio->num_stripes - 2; - q_stripe = bbio->num_stripes - 1; + if (rbio->real_stripes - rbio->nr_data == 1) { + p_stripe = rbio->real_stripes - 1; + } else if (rbio->real_stripes - rbio->nr_data == 2) { + p_stripe = rbio->real_stripes - 2; + q_stripe = rbio->real_stripes - 1; } else { BUG(); } @@ -1169,7 +1239,7 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio) set_bit(RBIO_RMW_LOCKED_BIT, &rbio->flags); spin_unlock_irq(&rbio->bio_list_lock); - atomic_set(&rbio->bbio->error, 0); + atomic_set(&rbio->error, 0); /* * now that we've set rmw_locked, run through the @@ -1209,7 +1279,7 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio) SetPageUptodate(p); pointers[stripe++] = kmap(p); - raid6_call.gen_syndrome(bbio->num_stripes, PAGE_SIZE, + raid6_call.gen_syndrome(rbio->real_stripes, PAGE_SIZE, pointers); } else { /* raid5 */ @@ -1218,7 +1288,7 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio) } - for (stripe = 0; stripe < bbio->num_stripes; stripe++) + for (stripe = 0; stripe < rbio->real_stripes; stripe++) kunmap(page_in_rbio(rbio, stripe, pagenr, 0)); } @@ -1227,7 +1297,7 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio) * higher layers (the bio_list in our rbio) and our p/q. Ignore * everything else. */ - for (stripe = 0; stripe < bbio->num_stripes; stripe++) { + for (stripe = 0; stripe < rbio->real_stripes; stripe++) { for (pagenr = 0; pagenr < pages_per_stripe; pagenr++) { struct page *page; if (stripe < rbio->nr_data) { @@ -1245,8 +1315,34 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio) } } - atomic_set(&bbio->stripes_pending, bio_list_size(&bio_list)); - BUG_ON(atomic_read(&bbio->stripes_pending) == 0); + if (likely(!bbio->num_tgtdevs)) + goto write_data; + + for (stripe = 0; stripe < rbio->real_stripes; stripe++) { + if (!bbio->tgtdev_map[stripe]) + continue; + + for (pagenr = 0; pagenr < pages_per_stripe; pagenr++) { + struct page *page; + if (stripe < rbio->nr_data) { + page = page_in_rbio(rbio, stripe, pagenr, 1); + if (!page) + continue; + } else { + page = rbio_stripe_page(rbio, stripe, pagenr); + } + + ret = rbio_add_io_page(rbio, &bio_list, page, + rbio->bbio->tgtdev_map[stripe], + pagenr, rbio->stripe_len); + if (ret) + goto cleanup; + } + } + +write_data: + atomic_set(&rbio->stripes_pending, bio_list_size(&bio_list)); + BUG_ON(atomic_read(&rbio->stripes_pending) == 0); while (1) { bio = bio_list_pop(&bio_list); @@ -1283,7 +1379,8 @@ static int find_bio_stripe(struct btrfs_raid_bio *rbio, stripe = &rbio->bbio->stripes[i]; stripe_start = stripe->physical; if (physical >= stripe_start && - physical < stripe_start + rbio->stripe_len) { + physical < stripe_start + rbio->stripe_len && + bio->bi_bdev == stripe->dev->bdev) { return i; } } @@ -1331,11 +1428,11 @@ static int fail_rbio_index(struct btrfs_raid_bio *rbio, int failed) if (rbio->faila == -1) { /* first failure on this rbio */ rbio->faila = failed; - atomic_inc(&rbio->bbio->error); + atomic_inc(&rbio->error); } else if (rbio->failb == -1) { /* second failure on this rbio */ rbio->failb = failed; - atomic_inc(&rbio->bbio->error); + atomic_inc(&rbio->error); } else { ret = -EIO; } @@ -1394,11 +1491,11 @@ static void raid_rmw_end_io(struct bio *bio, int err) bio_put(bio); - if (!atomic_dec_and_test(&rbio->bbio->stripes_pending)) + if (!atomic_dec_and_test(&rbio->stripes_pending)) return; err = 0; - if (atomic_read(&rbio->bbio->error) > rbio->bbio->max_errors) + if (atomic_read(&rbio->error) > rbio->bbio->max_errors) goto cleanup; /* @@ -1439,7 +1536,6 @@ static void async_read_rebuild(struct btrfs_raid_bio *rbio) static int raid56_rmw_stripe(struct btrfs_raid_bio *rbio) { int bios_to_read = 0; - struct btrfs_bio *bbio = rbio->bbio; struct bio_list bio_list; int ret; int nr_pages = DIV_ROUND_UP(rbio->stripe_len, PAGE_CACHE_SIZE); @@ -1455,7 +1551,7 @@ static int raid56_rmw_stripe(struct btrfs_raid_bio *rbio) index_rbio_pages(rbio); - atomic_set(&rbio->bbio->error, 0); + atomic_set(&rbio->error, 0); /* * build a list of bios to read all the missing parts of this * stripe @@ -1503,7 +1599,7 @@ static int raid56_rmw_stripe(struct btrfs_raid_bio *rbio) * the bbio may be freed once we submit the last bio. Make sure * not to touch it after that */ - atomic_set(&bbio->stripes_pending, bios_to_read); + atomic_set(&rbio->stripes_pending, bios_to_read); while (1) { bio = bio_list_pop(&bio_list); if (!bio) @@ -1686,19 +1782,30 @@ int raid56_parity_write(struct btrfs_root *root, struct bio *bio, struct btrfs_raid_bio *rbio; struct btrfs_plug_cb *plug = NULL; struct blk_plug_cb *cb; + int ret; rbio = alloc_rbio(root, bbio, raid_map, stripe_len); - if (IS_ERR(rbio)) + if (IS_ERR(rbio)) { + __free_bbio_and_raid_map(bbio, raid_map, 1); return PTR_ERR(rbio); + } bio_list_add(&rbio->bio_list, bio); rbio->bio_list_bytes = bio->bi_iter.bi_size; + rbio->operation = BTRFS_RBIO_WRITE; + + btrfs_bio_counter_inc_noblocked(root->fs_info); + rbio->generic_bio_cnt = 1; /* * don't plug on full rbios, just get them out the door * as quickly as we can */ - if (rbio_is_full(rbio)) - return full_stripe_write(rbio); + if (rbio_is_full(rbio)) { + ret = full_stripe_write(rbio); + if (ret) + btrfs_bio_counter_dec(root->fs_info); + return ret; + } cb = blk_check_plugged(btrfs_raid_unplug, root->fs_info, sizeof(*plug)); @@ -1709,10 +1816,13 @@ int raid56_parity_write(struct btrfs_root *root, struct bio *bio, INIT_LIST_HEAD(&plug->rbio_list); } list_add_tail(&rbio->plug_list, &plug->rbio_list); + ret = 0; } else { - return __raid56_parity_write(rbio); + ret = __raid56_parity_write(rbio); + if (ret) + btrfs_bio_counter_dec(root->fs_info); } - return 0; + return ret; } /* @@ -1730,7 +1840,7 @@ static void __raid_recover_end_io(struct btrfs_raid_bio *rbio) int err; int i; - pointers = kzalloc(rbio->bbio->num_stripes * sizeof(void *), + pointers = kzalloc(rbio->real_stripes * sizeof(void *), GFP_NOFS); if (!pointers) { err = -ENOMEM; @@ -1740,7 +1850,7 @@ static void __raid_recover_end_io(struct btrfs_raid_bio *rbio) faila = rbio->faila; failb = rbio->failb; - if (rbio->read_rebuild) { + if (rbio->operation == BTRFS_RBIO_READ_REBUILD) { spin_lock_irq(&rbio->bio_list_lock); set_bit(RBIO_RMW_LOCKED_BIT, &rbio->flags); spin_unlock_irq(&rbio->bio_list_lock); @@ -1749,15 +1859,23 @@ static void __raid_recover_end_io(struct btrfs_raid_bio *rbio) index_rbio_pages(rbio); for (pagenr = 0; pagenr < nr_pages; pagenr++) { + /* + * Now we just use bitmap to mark the horizontal stripes in + * which we have data when doing parity scrub. + */ + if (rbio->operation == BTRFS_RBIO_PARITY_SCRUB && + !test_bit(pagenr, rbio->dbitmap)) + continue; + /* setup our array of pointers with pages * from each stripe */ - for (stripe = 0; stripe < rbio->bbio->num_stripes; stripe++) { + for (stripe = 0; stripe < rbio->real_stripes; stripe++) { /* * if we're rebuilding a read, we have to use * pages from the bio list */ - if (rbio->read_rebuild && + if (rbio->operation == BTRFS_RBIO_READ_REBUILD && (stripe == faila || stripe == failb)) { page = page_in_rbio(rbio, stripe, pagenr, 0); } else { @@ -1767,7 +1885,7 @@ static void __raid_recover_end_io(struct btrfs_raid_bio *rbio) } /* all raid6 handling here */ - if (rbio->raid_map[rbio->bbio->num_stripes - 1] == + if (rbio->raid_map[rbio->real_stripes - 1] == RAID6_Q_STRIPE) { /* @@ -1817,10 +1935,10 @@ static void __raid_recover_end_io(struct btrfs_raid_bio *rbio) } if (rbio->raid_map[failb] == RAID5_P_STRIPE) { - raid6_datap_recov(rbio->bbio->num_stripes, + raid6_datap_recov(rbio->real_stripes, PAGE_SIZE, faila, pointers); } else { - raid6_2data_recov(rbio->bbio->num_stripes, + raid6_2data_recov(rbio->real_stripes, PAGE_SIZE, faila, failb, pointers); } @@ -1850,7 +1968,7 @@ pstripe: * know they can be trusted. If this was a read reconstruction, * other endio functions will fiddle the uptodate bits */ - if (!rbio->read_rebuild) { + if (rbio->operation == BTRFS_RBIO_WRITE) { for (i = 0; i < nr_pages; i++) { if (faila != -1) { page = rbio_stripe_page(rbio, faila, i); @@ -1862,12 +1980,12 @@ pstripe: } } } - for (stripe = 0; stripe < rbio->bbio->num_stripes; stripe++) { + for (stripe = 0; stripe < rbio->real_stripes; stripe++) { /* * if we're rebuilding a read, we have to use * pages from the bio list */ - if (rbio->read_rebuild && + if (rbio->operation == BTRFS_RBIO_READ_REBUILD && (stripe == faila || stripe == failb)) { page = page_in_rbio(rbio, stripe, pagenr, 0); } else { @@ -1882,9 +2000,9 @@ cleanup: kfree(pointers); cleanup_io: - - if (rbio->read_rebuild) { - if (err == 0) + if (rbio->operation == BTRFS_RBIO_READ_REBUILD) { + if (err == 0 && + !test_bit(RBIO_HOLD_BBIO_MAP_BIT, &rbio->flags)) cache_rbio_pages(rbio); else clear_bit(RBIO_CACHE_READY_BIT, &rbio->flags); @@ -1893,7 +2011,13 @@ cleanup_io: } else if (err == 0) { rbio->faila = -1; rbio->failb = -1; - finish_rmw(rbio); + + if (rbio->operation == BTRFS_RBIO_WRITE) + finish_rmw(rbio); + else if (rbio->operation == BTRFS_RBIO_PARITY_SCRUB) + finish_parity_scrub(rbio, 0); + else + BUG(); } else { rbio_orig_end_io(rbio, err, 0); } @@ -1917,10 +2041,10 @@ static void raid_recover_end_io(struct bio *bio, int err) set_bio_pages_uptodate(bio); bio_put(bio); - if (!atomic_dec_and_test(&rbio->bbio->stripes_pending)) + if (!atomic_dec_and_test(&rbio->stripes_pending)) return; - if (atomic_read(&rbio->bbio->error) > rbio->bbio->max_errors) + if (atomic_read(&rbio->error) > rbio->bbio->max_errors) rbio_orig_end_io(rbio, -EIO, 0); else __raid_recover_end_io(rbio); @@ -1937,7 +2061,6 @@ static void raid_recover_end_io(struct bio *bio, int err) static int __raid56_parity_recover(struct btrfs_raid_bio *rbio) { int bios_to_read = 0; - struct btrfs_bio *bbio = rbio->bbio; struct bio_list bio_list; int ret; int nr_pages = DIV_ROUND_UP(rbio->stripe_len, PAGE_CACHE_SIZE); @@ -1951,16 +2074,16 @@ static int __raid56_parity_recover(struct btrfs_raid_bio *rbio) if (ret) goto cleanup; - atomic_set(&rbio->bbio->error, 0); + atomic_set(&rbio->error, 0); /* * read everything that hasn't failed. Thanks to the * stripe cache, it is possible that some or all of these * pages are going to be uptodate. */ - for (stripe = 0; stripe < bbio->num_stripes; stripe++) { + for (stripe = 0; stripe < rbio->real_stripes; stripe++) { if (rbio->faila == stripe || rbio->failb == stripe) { - atomic_inc(&rbio->bbio->error); + atomic_inc(&rbio->error); continue; } @@ -1990,7 +2113,7 @@ static int __raid56_parity_recover(struct btrfs_raid_bio *rbio) * were up to date, or we might have no bios to read because * the devices were gone. */ - if (atomic_read(&rbio->bbio->error) <= rbio->bbio->max_errors) { + if (atomic_read(&rbio->error) <= rbio->bbio->max_errors) { __raid_recover_end_io(rbio); goto out; } else { @@ -2002,7 +2125,7 @@ static int __raid56_parity_recover(struct btrfs_raid_bio *rbio) * the bbio may be freed once we submit the last bio. Make sure * not to touch it after that */ - atomic_set(&bbio->stripes_pending, bios_to_read); + atomic_set(&rbio->stripes_pending, bios_to_read); while (1) { bio = bio_list_pop(&bio_list); if (!bio) @@ -2021,7 +2144,7 @@ out: return 0; cleanup: - if (rbio->read_rebuild) + if (rbio->operation == BTRFS_RBIO_READ_REBUILD) rbio_orig_end_io(rbio, -EIO, 0); return -EIO; } @@ -2034,34 +2157,42 @@ cleanup: */ int raid56_parity_recover(struct btrfs_root *root, struct bio *bio, struct btrfs_bio *bbio, u64 *raid_map, - u64 stripe_len, int mirror_num) + u64 stripe_len, int mirror_num, int generic_io) { struct btrfs_raid_bio *rbio; int ret; rbio = alloc_rbio(root, bbio, raid_map, stripe_len); - if (IS_ERR(rbio)) + if (IS_ERR(rbio)) { + __free_bbio_and_raid_map(bbio, raid_map, generic_io); return PTR_ERR(rbio); + } - rbio->read_rebuild = 1; + rbio->operation = BTRFS_RBIO_READ_REBUILD; bio_list_add(&rbio->bio_list, bio); rbio->bio_list_bytes = bio->bi_iter.bi_size; rbio->faila = find_logical_bio_stripe(rbio, bio); if (rbio->faila == -1) { BUG(); - kfree(raid_map); - kfree(bbio); + __free_bbio_and_raid_map(bbio, raid_map, generic_io); kfree(rbio); return -EIO; } + if (generic_io) { + btrfs_bio_counter_inc_noblocked(root->fs_info); + rbio->generic_bio_cnt = 1; + } else { + set_bit(RBIO_HOLD_BBIO_MAP_BIT, &rbio->flags); + } + /* * reconstruct from the q stripe if they are * asking for mirror 3 */ if (mirror_num == 3) - rbio->failb = bbio->num_stripes - 2; + rbio->failb = rbio->real_stripes - 2; ret = lock_stripe_add(rbio); @@ -2098,3 +2229,483 @@ static void read_rebuild_work(struct btrfs_work *work) rbio = container_of(work, struct btrfs_raid_bio, work); __raid56_parity_recover(rbio); } + +/* + * The following code is used to scrub/replace the parity stripe + * + * Note: We need make sure all the pages that add into the scrub/replace + * raid bio are correct and not be changed during the scrub/replace. That + * is those pages just hold metadata or file data with checksum. + */ + +struct btrfs_raid_bio * +raid56_parity_alloc_scrub_rbio(struct btrfs_root *root, struct bio *bio, + struct btrfs_bio *bbio, u64 *raid_map, + u64 stripe_len, struct btrfs_device *scrub_dev, + unsigned long *dbitmap, int stripe_nsectors) +{ + struct btrfs_raid_bio *rbio; + int i; + + rbio = alloc_rbio(root, bbio, raid_map, stripe_len); + if (IS_ERR(rbio)) + return NULL; + bio_list_add(&rbio->bio_list, bio); + /* + * This is a special bio which is used to hold the completion handler + * and make the scrub rbio is similar to the other types + */ + ASSERT(!bio->bi_iter.bi_size); + rbio->operation = BTRFS_RBIO_PARITY_SCRUB; + + for (i = 0; i < rbio->real_stripes; i++) { + if (bbio->stripes[i].dev == scrub_dev) { + rbio->scrubp = i; + break; + } + } + + /* Now we just support the sectorsize equals to page size */ + ASSERT(root->sectorsize == PAGE_SIZE); + ASSERT(rbio->stripe_npages == stripe_nsectors); + bitmap_copy(rbio->dbitmap, dbitmap, stripe_nsectors); + + return rbio; +} + +void raid56_parity_add_scrub_pages(struct btrfs_raid_bio *rbio, + struct page *page, u64 logical) +{ + int stripe_offset; + int index; + + ASSERT(logical >= rbio->raid_map[0]); + ASSERT(logical + PAGE_SIZE <= rbio->raid_map[0] + + rbio->stripe_len * rbio->nr_data); + stripe_offset = (int)(logical - rbio->raid_map[0]); + index = stripe_offset >> PAGE_CACHE_SHIFT; + rbio->bio_pages[index] = page; +} + +/* + * We just scrub the parity that we have correct data on the same horizontal, + * so we needn't allocate all pages for all the stripes. + */ +static int alloc_rbio_essential_pages(struct btrfs_raid_bio *rbio) +{ + int i; + int bit; + int index; + struct page *page; + + for_each_set_bit(bit, rbio->dbitmap, rbio->stripe_npages) { + for (i = 0; i < rbio->real_stripes; i++) { + index = i * rbio->stripe_npages + bit; + if (rbio->stripe_pages[index]) + continue; + + page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); + if (!page) + return -ENOMEM; + rbio->stripe_pages[index] = page; + ClearPageUptodate(page); + } + } + return 0; +} + +/* + * end io function used by finish_rmw. When we finally + * get here, we've written a full stripe + */ +static void raid_write_parity_end_io(struct bio *bio, int err) +{ + struct btrfs_raid_bio *rbio = bio->bi_private; + + if (err) + fail_bio_stripe(rbio, bio); + + bio_put(bio); + + if (!atomic_dec_and_test(&rbio->stripes_pending)) + return; + + err = 0; + + if (atomic_read(&rbio->error)) + err = -EIO; + + rbio_orig_end_io(rbio, err, 0); +} + +static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio, + int need_check) +{ + struct btrfs_bio *bbio = rbio->bbio; + void *pointers[rbio->real_stripes]; + DECLARE_BITMAP(pbitmap, rbio->stripe_npages); + int nr_data = rbio->nr_data; + int stripe; + int pagenr; + int p_stripe = -1; + int q_stripe = -1; + struct page *p_page = NULL; + struct page *q_page = NULL; + struct bio_list bio_list; + struct bio *bio; + int is_replace = 0; + int ret; + + bio_list_init(&bio_list); + + if (rbio->real_stripes - rbio->nr_data == 1) { + p_stripe = rbio->real_stripes - 1; + } else if (rbio->real_stripes - rbio->nr_data == 2) { + p_stripe = rbio->real_stripes - 2; + q_stripe = rbio->real_stripes - 1; + } else { + BUG(); + } + + if (bbio->num_tgtdevs && bbio->tgtdev_map[rbio->scrubp]) { + is_replace = 1; + bitmap_copy(pbitmap, rbio->dbitmap, rbio->stripe_npages); + } + + /* + * Because the higher layers(scrubber) are unlikely to + * use this area of the disk again soon, so don't cache + * it. + */ + clear_bit(RBIO_CACHE_READY_BIT, &rbio->flags); + + if (!need_check) + goto writeback; + + p_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); + if (!p_page) + goto cleanup; + SetPageUptodate(p_page); + + if (q_stripe != -1) { + q_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); + if (!q_page) { + __free_page(p_page); + goto cleanup; + } + SetPageUptodate(q_page); + } + + atomic_set(&rbio->error, 0); + + for_each_set_bit(pagenr, rbio->dbitmap, rbio->stripe_npages) { + struct page *p; + void *parity; + /* first collect one page from each data stripe */ + for (stripe = 0; stripe < nr_data; stripe++) { + p = page_in_rbio(rbio, stripe, pagenr, 0); + pointers[stripe] = kmap(p); + } + + /* then add the parity stripe */ + pointers[stripe++] = kmap(p_page); + + if (q_stripe != -1) { + + /* + * raid6, add the qstripe and call the + * library function to fill in our p/q + */ + pointers[stripe++] = kmap(q_page); + + raid6_call.gen_syndrome(rbio->real_stripes, PAGE_SIZE, + pointers); + } else { + /* raid5 */ + memcpy(pointers[nr_data], pointers[0], PAGE_SIZE); + run_xor(pointers + 1, nr_data - 1, PAGE_CACHE_SIZE); + } + + /* Check scrubbing pairty and repair it */ + p = rbio_stripe_page(rbio, rbio->scrubp, pagenr); + parity = kmap(p); + if (memcmp(parity, pointers[rbio->scrubp], PAGE_CACHE_SIZE)) + memcpy(parity, pointers[rbio->scrubp], PAGE_CACHE_SIZE); + else + /* Parity is right, needn't writeback */ + bitmap_clear(rbio->dbitmap, pagenr, 1); + kunmap(p); + + for (stripe = 0; stripe < rbio->real_stripes; stripe++) + kunmap(page_in_rbio(rbio, stripe, pagenr, 0)); + } + + __free_page(p_page); + if (q_page) + __free_page(q_page); + +writeback: + /* + * time to start writing. Make bios for everything from the + * higher layers (the bio_list in our rbio) and our p/q. Ignore + * everything else. + */ + for_each_set_bit(pagenr, rbio->dbitmap, rbio->stripe_npages) { + struct page *page; + + page = rbio_stripe_page(rbio, rbio->scrubp, pagenr); + ret = rbio_add_io_page(rbio, &bio_list, + page, rbio->scrubp, pagenr, rbio->stripe_len); + if (ret) + goto cleanup; + } + + if (!is_replace) + goto submit_write; + + for_each_set_bit(pagenr, pbitmap, rbio->stripe_npages) { + struct page *page; + + page = rbio_stripe_page(rbio, rbio->scrubp, pagenr); + ret = rbio_add_io_page(rbio, &bio_list, page, + bbio->tgtdev_map[rbio->scrubp], + pagenr, rbio->stripe_len); + if (ret) + goto cleanup; + } + +submit_write: + nr_data = bio_list_size(&bio_list); + if (!nr_data) { + /* Every parity is right */ + rbio_orig_end_io(rbio, 0, 0); + return; + } + + atomic_set(&rbio->stripes_pending, nr_data); + + while (1) { + bio = bio_list_pop(&bio_list); + if (!bio) + break; + + bio->bi_private = rbio; + bio->bi_end_io = raid_write_parity_end_io; + BUG_ON(!test_bit(BIO_UPTODATE, &bio->bi_flags)); + submit_bio(WRITE, bio); + } + return; + +cleanup: + rbio_orig_end_io(rbio, -EIO, 0); +} + +static inline int is_data_stripe(struct btrfs_raid_bio *rbio, int stripe) +{ + if (stripe >= 0 && stripe < rbio->nr_data) + return 1; + return 0; +} + +/* + * While we're doing the parity check and repair, we could have errors + * in reading pages off the disk. This checks for errors and if we're + * not able to read the page it'll trigger parity reconstruction. The + * parity scrub will be finished after we've reconstructed the failed + * stripes + */ +static void validate_rbio_for_parity_scrub(struct btrfs_raid_bio *rbio) +{ + if (atomic_read(&rbio->error) > rbio->bbio->max_errors) + goto cleanup; + + if (rbio->faila >= 0 || rbio->failb >= 0) { + int dfail = 0, failp = -1; + + if (is_data_stripe(rbio, rbio->faila)) + dfail++; + else if (is_parity_stripe(rbio->faila)) + failp = rbio->faila; + + if (is_data_stripe(rbio, rbio->failb)) + dfail++; + else if (is_parity_stripe(rbio->failb)) + failp = rbio->failb; + + /* + * Because we can not use a scrubbing parity to repair + * the data, so the capability of the repair is declined. + * (In the case of RAID5, we can not repair anything) + */ + if (dfail > rbio->bbio->max_errors - 1) + goto cleanup; + + /* + * If all data is good, only parity is correctly, just + * repair the parity. + */ + if (dfail == 0) { + finish_parity_scrub(rbio, 0); + return; + } + + /* + * Here means we got one corrupted data stripe and one + * corrupted parity on RAID6, if the corrupted parity + * is scrubbing parity, luckly, use the other one to repair + * the data, or we can not repair the data stripe. + */ + if (failp != rbio->scrubp) + goto cleanup; + + __raid_recover_end_io(rbio); + } else { + finish_parity_scrub(rbio, 1); + } + return; + +cleanup: + rbio_orig_end_io(rbio, -EIO, 0); +} + +/* + * end io for the read phase of the rmw cycle. All the bios here are physical + * stripe bios we've read from the disk so we can recalculate the parity of the + * stripe. + * + * This will usually kick off finish_rmw once all the bios are read in, but it + * may trigger parity reconstruction if we had any errors along the way + */ +static void raid56_parity_scrub_end_io(struct bio *bio, int err) +{ + struct btrfs_raid_bio *rbio = bio->bi_private; + + if (err) + fail_bio_stripe(rbio, bio); + else + set_bio_pages_uptodate(bio); + + bio_put(bio); + + if (!atomic_dec_and_test(&rbio->stripes_pending)) + return; + + /* + * this will normally call finish_rmw to start our write + * but if there are any failed stripes we'll reconstruct + * from parity first + */ + validate_rbio_for_parity_scrub(rbio); +} + +static void raid56_parity_scrub_stripe(struct btrfs_raid_bio *rbio) +{ + int bios_to_read = 0; + struct bio_list bio_list; + int ret; + int pagenr; + int stripe; + struct bio *bio; + + ret = alloc_rbio_essential_pages(rbio); + if (ret) + goto cleanup; + + bio_list_init(&bio_list); + + atomic_set(&rbio->error, 0); + /* + * build a list of bios to read all the missing parts of this + * stripe + */ + for (stripe = 0; stripe < rbio->real_stripes; stripe++) { + for_each_set_bit(pagenr, rbio->dbitmap, rbio->stripe_npages) { + struct page *page; + /* + * we want to find all the pages missing from + * the rbio and read them from the disk. If + * page_in_rbio finds a page in the bio list + * we don't need to read it off the stripe. + */ + page = page_in_rbio(rbio, stripe, pagenr, 1); + if (page) + continue; + + page = rbio_stripe_page(rbio, stripe, pagenr); + /* + * the bio cache may have handed us an uptodate + * page. If so, be happy and use it + */ + if (PageUptodate(page)) + continue; + + ret = rbio_add_io_page(rbio, &bio_list, page, + stripe, pagenr, rbio->stripe_len); + if (ret) + goto cleanup; + } + } + + bios_to_read = bio_list_size(&bio_list); + if (!bios_to_read) { + /* + * this can happen if others have merged with + * us, it means there is nothing left to read. + * But if there are missing devices it may not be + * safe to do the full stripe write yet. + */ + goto finish; + } + + /* + * the bbio may be freed once we submit the last bio. Make sure + * not to touch it after that + */ + atomic_set(&rbio->stripes_pending, bios_to_read); + while (1) { + bio = bio_list_pop(&bio_list); + if (!bio) + break; + + bio->bi_private = rbio; + bio->bi_end_io = raid56_parity_scrub_end_io; + + btrfs_bio_wq_end_io(rbio->fs_info, bio, + BTRFS_WQ_ENDIO_RAID56); + + BUG_ON(!test_bit(BIO_UPTODATE, &bio->bi_flags)); + submit_bio(READ, bio); + } + /* the actual write will happen once the reads are done */ + return; + +cleanup: + rbio_orig_end_io(rbio, -EIO, 0); + return; + +finish: + validate_rbio_for_parity_scrub(rbio); +} + +static void scrub_parity_work(struct btrfs_work *work) +{ + struct btrfs_raid_bio *rbio; + + rbio = container_of(work, struct btrfs_raid_bio, work); + raid56_parity_scrub_stripe(rbio); +} + +static void async_scrub_parity(struct btrfs_raid_bio *rbio) +{ + btrfs_init_work(&rbio->work, btrfs_rmw_helper, + scrub_parity_work, NULL, NULL); + + btrfs_queue_work(rbio->fs_info->rmw_workers, + &rbio->work); +} + +void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio) +{ + if (!lock_stripe_add(rbio)) + async_scrub_parity(rbio); +} |
