From: Yi Li yili@winhong.com

mainline inclusion from v5.11-rc1 commit 117ae250cfa3718f21bd07df0650dfbe3bc3a823 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

There have no reassign the bdev after check It is IS_ERR. the double check !IS_ERR(bdev) is superfluous.

After commit 4e7b5671c6a8 ("block: remove i_bdev"), "Switch the block device lookup interfaces to directly work with a dev_t so that struct block_device references are only acquired by the blkdev_get variants (and the blk-cgroup special case). This means that we now don't need an extra reference in the inode and can generally simplify handling of struct block_device to keep the lookups contained in the core block layer code."

so after lookup_bdev call, there no need to do bdput.

remove a superfluous check the bdev & don't call bdput after lookup_bdev.

Fixes: 4e7b5671c6a8("block: remove i_bdev") Signed-off-by: Yi Li yili@winhong.com Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Coly Li colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/super.c | 2 -- 1 file changed, 2 deletions(-)

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index b7d9d1b79ac2..1572190c32ec 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -2588,8 +2588,6 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, else err = "device busy"; mutex_unlock(&bch_register_lock); - if (!IS_ERR(bdev)) - bdput(bdev); if (attr == &ksysfs_register_quiet) goto done; }

From: Yi Li yili@winhong.com

mainline inclusion from v5.11-rc3 commit e80927079fd97b4d5457e3af2400a0087b561564 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

There is no need to reassign pdev_set_uuid in the second loop iteration, so move it to the place before second loop.

Signed-off-by: Yi Li yili@winhong.com Signed-off-by: Coly Li colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 1572190c32ec..456e41a81c06 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -2697,8 +2697,8 @@ static ssize_t bch_pending_bdevs_cleanup(struct kobject *k, }

list_for_each_entry_safe(pdev, tpdev, &pending_devs, list) { + char *pdev_set_uuid = pdev->dc->sb.set_uuid; list_for_each_entry_safe(c, tc, &bch_cache_sets, list) { - char *pdev_set_uuid = pdev->dc->sb.set_uuid; char *set_uuid = c->set_uuid;

if (!memcmp(pdev_set_uuid, set_uuid, 16)) {

From: dongdong tao dongdong.tao@canonical.com

mainline inclusion from v5.12-rc1 commit 71dda2a5625f31bc3410cb69c3d31376a2b66f28 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

Current way to calculate the writeback rate only considered the dirty sectors, this usually works fine when the fragmentation is not high, but it will give us unreasonable small rate when we are under a situation that very few dirty sectors consumed a lot dirty buckets. In some case, the dirty bucekts can reached to CUTOFF_WRITEBACK_SYNC while the dirty data(sectors) not even reached the writeback_percent, the writeback rate will still be the minimum value (4k), thus it will cause all the writes to be stucked in a non-writeback mode because of the slow writeback.

We accelerate the rate in 3 stages with different aggressiveness, the first stage starts when dirty buckets percent reach above BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW (50), the second is BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID (57), the third is BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH (64). By default the first stage tries to writeback the amount of dirty data in one bucket (on average) in (1 / (dirty_buckets_percent - 50)) second, the second stage tries to writeback the amount of dirty data in one bucket in (1 / (dirty_buckets_percent - 57)) * 100 millisecond, the third stage tries to writeback the amount of dirty data in one bucket in (1 / (dirty_buckets_percent - 64)) millisecond.

the initial rate at each stage can be controlled by 3 configurable parameters writeback_rate_fp_term_{low|mid|high}, they are by default 1, 10, 1000, the hint of IO throughput that these values are trying to achieve is described by above paragraph, the reason that I choose those value as default is based on the testing and the production data, below is some details:

A. When it comes to the low stage, there is still a bit far from the 70 threshold, so we only want to give it a little bit push by setting the term to 1, it means the initial rate will be 170 if the fragment is 6, it is calculated by bucket_size/fragment, this rate is very small, but still much reasonable than the minimum 8. For a production bcache with unheavy workload, if the cache device is bigger than 1 TB, it may take hours to consume 1% buckets, so it is very possible to reclaim enough dirty buckets in this stage, thus to avoid entering the next stage.

B. If the dirty buckets ratio didn't turn around during the first stage, it comes to the mid stage, then it is necessary for mid stage to be more aggressive than low stage, so i choose the initial rate to be 10 times more than low stage, that means 1700 as the initial rate if the fragment is 6. This is some normal rate we usually see for a normal workload when writeback happens because of writeback_percent.

C. If the dirty buckets ratio didn't turn around during the low and mid stages, it comes to the third stage, and it is the last chance that we can turn around to avoid the horrible cutoff writeback sync issue, then we choose 100 times more aggressive than the mid stage, that means 170000 as the initial rate if the fragment is 6. This is also inferred from a production bcache, I've got one week's writeback rate data from a production bcache which has quite heavy workloads, again, the writeback is triggered by the writeback percent, the highest rate area is around 100000 to 240000, so I believe this kind aggressiveness at this stage is reasonable for production. And it should be mostly enough because the hint is trying to reclaim 1000 bucket per second, and from that heavy production env, it is consuming 50 bucket per second on average in one week's data.

Option writeback_consider_fragment is to control whether we want this feature to be on or off, it's on by default.

Lastly, below is the performance data for all the testing result, including the data from production env: https://docs.google.com/document/d/1AmbIEa_2MhB9bqhC3rfga9tp7n9YX9PLn0jSUxsc...

Signed-off-by: dongdong tao dongdong.tao@canonical.com Signed-off-by: Coly Li colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/bcache.h | 4 ++++ drivers/md/bcache/sysfs.c | 23 +++++++++++++++++++ drivers/md/bcache/writeback.c | 42 +++++++++++++++++++++++++++++++++++ drivers/md/bcache/writeback.h | 4 ++++ 4 files changed, 73 insertions(+)

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index e8bf4f752e8b..848dd4db1659 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -373,6 +373,7 @@ struct cached_dev { unsigned int partial_stripes_expensive:1; unsigned int writeback_metadata:1; unsigned int writeback_running:1; + unsigned int writeback_consider_fragment:1; unsigned char writeback_percent; unsigned int writeback_delay;

@@ -385,6 +386,9 @@ struct cached_dev { unsigned int writeback_rate_update_seconds; unsigned int writeback_rate_i_term_inverse; unsigned int writeback_rate_p_term_inverse; + unsigned int writeback_rate_fp_term_low; + unsigned int writeback_rate_fp_term_mid; + unsigned int writeback_rate_fp_term_high; unsigned int writeback_rate_minimum;

enum stop_on_failure stop_when_cache_set_failed; diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index 00a520c03f41..eef15f8022ba 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -117,10 +117,14 @@ rw_attribute(writeback_running); rw_attribute(writeback_percent); rw_attribute(writeback_delay); rw_attribute(writeback_rate); +rw_attribute(writeback_consider_fragment);

rw_attribute(writeback_rate_update_seconds); rw_attribute(writeback_rate_i_term_inverse); rw_attribute(writeback_rate_p_term_inverse); +rw_attribute(writeback_rate_fp_term_low); +rw_attribute(writeback_rate_fp_term_mid); +rw_attribute(writeback_rate_fp_term_high); rw_attribute(writeback_rate_minimum); read_attribute(writeback_rate_debug);

@@ -195,6 +199,7 @@ SHOW(__bch_cached_dev) var_printf(bypass_torture_test, "%i"); var_printf(writeback_metadata, "%i"); var_printf(writeback_running, "%i"); + var_printf(writeback_consider_fragment, "%i"); var_print(writeback_delay); var_print(writeback_percent); sysfs_hprint(writeback_rate, @@ -205,6 +210,9 @@ SHOW(__bch_cached_dev) var_print(writeback_rate_update_seconds); var_print(writeback_rate_i_term_inverse); var_print(writeback_rate_p_term_inverse); + var_print(writeback_rate_fp_term_low); + var_print(writeback_rate_fp_term_mid); + var_print(writeback_rate_fp_term_high); var_print(writeback_rate_minimum);

if (attr == &sysfs_writeback_rate_debug) { @@ -303,6 +311,7 @@ STORE(__cached_dev) sysfs_strtoul_bool(bypass_torture_test, dc->bypass_torture_test); sysfs_strtoul_bool(writeback_metadata, dc->writeback_metadata); sysfs_strtoul_bool(writeback_running, dc->writeback_running); + sysfs_strtoul_bool(writeback_consider_fragment, dc->writeback_consider_fragment); sysfs_strtoul_clamp(writeback_delay, dc->writeback_delay, 0, UINT_MAX);

sysfs_strtoul_clamp(writeback_percent, dc->writeback_percent, @@ -331,6 +340,16 @@ STORE(__cached_dev) sysfs_strtoul_clamp(writeback_rate_p_term_inverse, dc->writeback_rate_p_term_inverse, 1, UINT_MAX); + sysfs_strtoul_clamp(writeback_rate_fp_term_low, + dc->writeback_rate_fp_term_low, + 1, dc->writeback_rate_fp_term_mid - 1); + sysfs_strtoul_clamp(writeback_rate_fp_term_mid, + dc->writeback_rate_fp_term_mid, + dc->writeback_rate_fp_term_low + 1, + dc->writeback_rate_fp_term_high - 1); + sysfs_strtoul_clamp(writeback_rate_fp_term_high, + dc->writeback_rate_fp_term_high, + dc->writeback_rate_fp_term_mid + 1, UINT_MAX); sysfs_strtoul_clamp(writeback_rate_minimum, dc->writeback_rate_minimum, 1, UINT_MAX); @@ -499,9 +518,13 @@ static struct attribute *bch_cached_dev_files[] = { &sysfs_writeback_delay, &sysfs_writeback_percent, &sysfs_writeback_rate, + &sysfs_writeback_consider_fragment, &sysfs_writeback_rate_update_seconds, &sysfs_writeback_rate_i_term_inverse, &sysfs_writeback_rate_p_term_inverse, + &sysfs_writeback_rate_fp_term_low, + &sysfs_writeback_rate_fp_term_mid, + &sysfs_writeback_rate_fp_term_high, &sysfs_writeback_rate_minimum, &sysfs_writeback_rate_debug, &sysfs_io_errors, diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index a129e4d2707c..82d4e0880a99 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -88,6 +88,44 @@ static void __update_writeback_rate(struct cached_dev *dc) int64_t integral_scaled; uint32_t new_rate;

+ /* + * We need to consider the number of dirty buckets as well + * when calculating the proportional_scaled, Otherwise we might + * have an unreasonable small writeback rate at a highly fragmented situation + * when very few dirty sectors consumed a lot dirty buckets, the + * worst case is when dirty buckets reached cutoff_writeback_sync and + * dirty data is still not even reached to writeback percent, so the rate + * still will be at the minimum value, which will cause the write + * stuck at a non-writeback mode. + */ + struct cache_set *c = dc->disk.c; + + int64_t dirty_buckets = c->nbuckets - c->avail_nbuckets; + + if (dc->writeback_consider_fragment && + c->gc_stats.in_use > BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW && dirty > 0) { + int64_t fragment = + div_s64((dirty_buckets * c->cache->sb.bucket_size), dirty); + int64_t fp_term; + int64_t fps; + + if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID) { + fp_term = dc->writeback_rate_fp_term_low * + (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW); + } else if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH) { + fp_term = dc->writeback_rate_fp_term_mid * + (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID); + } else { + fp_term = dc->writeback_rate_fp_term_high * + (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH); + } + fps = div_s64(dirty, dirty_buckets) * fp_term; + if (fragment > 3 && fps > proportional_scaled) { + /* Only overrite the p when fragment > 3 */ + proportional_scaled = fps; + } + } + if ((error < 0 && dc->writeback_rate_integral > 0) || (error > 0 && time_before64(local_clock(), dc->writeback_rate.next + NSEC_PER_MSEC))) { @@ -977,6 +1015,7 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc)

dc->writeback_metadata = true; dc->writeback_running = false; + dc->writeback_consider_fragment = true; dc->writeback_percent = 10; dc->writeback_delay = 30; atomic_long_set(&dc->writeback_rate.rate, 1024); @@ -984,6 +1023,9 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc)

dc->writeback_rate_update_seconds = WRITEBACK_RATE_UPDATE_SECS_DEFAULT; dc->writeback_rate_p_term_inverse = 40; + dc->writeback_rate_fp_term_low = 1; + dc->writeback_rate_fp_term_mid = 10; + dc->writeback_rate_fp_term_high = 1000; dc->writeback_rate_i_term_inverse = 10000;

WARN_ON(test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)); diff --git a/drivers/md/bcache/writeback.h b/drivers/md/bcache/writeback.h index 3f1230e22de0..02b2f9df73f6 100644 --- a/drivers/md/bcache/writeback.h +++ b/drivers/md/bcache/writeback.h @@ -16,6 +16,10 @@

#define BCH_AUTO_GC_DIRTY_THRESHOLD 50

+#define BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW 50 +#define BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID 57 +#define BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH 64 + #define BCH_DIRTY_INIT_THRD_MAX 64 /* * 14 (16384ths) is chosen here as something that each backing device

From: Joe Perches joe@perches.com

mainline inclusion from v5.12-rc1 commit 6751c1e3cff3aa763c760c08862627069a37b50e category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

Use semicolons and braces.

Signed-off-by: Joe Perches joe@perches.com Signed-off-by: Coly Li colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/bset.c | 12 ++++++++---- drivers/md/bcache/sysfs.c | 6 ++++-- 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c index 67a2c47f4201..94d38e8a59b3 100644 --- a/drivers/md/bcache/bset.c +++ b/drivers/md/bcache/bset.c @@ -712,8 +712,10 @@ void bch_bset_build_written_tree(struct btree_keys *b) for (j = inorder_next(0, t->size); j; j = inorder_next(j, t->size)) { - while (bkey_to_cacheline(t, k) < cacheline) - prev = k, k = bkey_next(k); + while (bkey_to_cacheline(t, k) < cacheline) { + prev = k; + k = bkey_next(k); + }

t->prev[j] = bkey_u64s(prev); t->tree[j].m = bkey_to_cacheline_offset(t, cacheline++, k); @@ -901,8 +903,10 @@ unsigned int bch_btree_insert_key(struct btree_keys *b, struct bkey *k, status = BTREE_INSERT_STATUS_INSERT;

while (m != bset_bkey_last(i) && - bkey_cmp(k, b->ops->is_extents ? &START_KEY(m) : m) > 0) - prev = m, m = bkey_next(m); + bkey_cmp(k, b->ops->is_extents ? &START_KEY(m) : m) > 0) { + prev = m; + m = bkey_next(m); + }

/* prev is in the tree, if we merge we're done */ status = BTREE_INSERT_STATUS_BACK_MERGE; diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index eef15f8022ba..cc89f3156d1a 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -1094,8 +1094,10 @@ SHOW(__bch_cache) --n;

while (cached < p + n && - *cached == BTREE_PRIO) - cached++, n--; + *cached == BTREE_PRIO) { + cached++; + n--; + }

for (i = 0; i < n; i++) sum += INITIAL_PRIO - cached[i];

From: Christoph Hellwig hch@lst.de

mainline inclusion from 5.13-rc1 commit 11e9560e6c005b4adca12d17b27dc5ac22b40663 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

Remove the PTR_CACHE inline and replace it with a direct dereference of c->cache.

(Coly Li: fix the typo from PTR_BUCKET to PTR_CACHE in commit log)

Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20210411134316.80274-3-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/alloc.c | 5 ++--- drivers/md/bcache/bcache.h | 11 ++--------- drivers/md/bcache/btree.c | 4 ++-- drivers/md/bcache/debug.c | 2 +- drivers/md/bcache/extents.c | 4 ++-- drivers/md/bcache/io.c | 4 ++-- drivers/md/bcache/journal.c | 2 +- drivers/md/bcache/writeback.c | 5 ++--- 8 files changed, 14 insertions(+), 23 deletions(-)

diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c index 8c371d5eef8e..097577ae3c47 100644 --- a/drivers/md/bcache/alloc.c +++ b/drivers/md/bcache/alloc.c @@ -482,8 +482,7 @@ void bch_bucket_free(struct cache_set *c, struct bkey *k) unsigned int i;

for (i = 0; i < KEY_PTRS(k); i++) - __bch_bucket_free(PTR_CACHE(c, k, i), - PTR_BUCKET(c, k, i)); + __bch_bucket_free(c->cache, PTR_BUCKET(c, k, i)); }

int __bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, @@ -674,7 +673,7 @@ bool bch_alloc_sectors(struct cache_set *c, SET_PTR_OFFSET(&b->key, i, PTR_OFFSET(&b->key, i) + sectors);

atomic_long_add(sectors, - &PTR_CACHE(c, &b->key, i)->sectors_written); + &c->cache->sectors_written); }

if (b->sectors_free < c->cache->sb.block_size) diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 848dd4db1659..0a4551e165ab 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -804,13 +804,6 @@ static inline sector_t bucket_remainder(struct cache_set *c, sector_t s) return s & (c->cache->sb.bucket_size - 1); }

-static inline struct cache *PTR_CACHE(struct cache_set *c, - const struct bkey *k, - unsigned int ptr) -{ - return c->cache; -} - static inline size_t PTR_BUCKET_NR(struct cache_set *c, const struct bkey *k, unsigned int ptr) @@ -822,7 +815,7 @@ static inline struct bucket *PTR_BUCKET(struct cache_set *c, const struct bkey *k, unsigned int ptr) { - return PTR_CACHE(c, k, ptr)->buckets + PTR_BUCKET_NR(c, k, ptr); + return c->cache->buckets + PTR_BUCKET_NR(c, k, ptr); }

static inline uint8_t gen_after(uint8_t a, uint8_t b) @@ -841,7 +834,7 @@ static inline uint8_t ptr_stale(struct cache_set *c, const struct bkey *k, static inline bool ptr_available(struct cache_set *c, const struct bkey *k, unsigned int i) { - return (PTR_DEV(k, i) < MAX_CACHES_PER_SET) && PTR_CACHE(c, k, i); + return (PTR_DEV(k, i) < MAX_CACHES_PER_SET) && c->cache; }

/* Btree key macros */ diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index fe6dce125aba..183a58c89377 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -426,7 +426,7 @@ void __bch_btree_node_write(struct btree *b, struct closure *parent) do_btree_node_write(b);

atomic_long_add(set_blocks(i, block_bytes(b->c->cache)) * b->c->cache->sb.block_size, - &PTR_CACHE(b->c, &b->key, 0)->btree_sectors_written); + &b->c->cache->btree_sectors_written);

b->written += set_blocks(i, block_bytes(b->c->cache)); } @@ -1161,7 +1161,7 @@ static void make_btree_freeing_key(struct btree *b, struct bkey *k)

for (i = 0; i < KEY_PTRS(k); i++) SET_PTR_GEN(k, i, - bch_inc_gen(PTR_CACHE(b->c, &b->key, i), + bch_inc_gen(b->c->cache, PTR_BUCKET(b->c, &b->key, i)));

mutex_unlock(&b->c->bucket_lock); diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c index b00fd08d696b..b2eb59b9cd71 100644 --- a/drivers/md/bcache/debug.c +++ b/drivers/md/bcache/debug.c @@ -50,7 +50,7 @@ void bch_btree_verify(struct btree *b) v->keys.ops = b->keys.ops;

bio = bch_bbio_alloc(b->c); - bio_set_dev(bio, PTR_CACHE(b->c, &b->key, 0)->bdev); + bio_set_dev(bio, c->cache->bdev); bio->bi_iter.bi_sector = PTR_OFFSET(&b->key, 0); bio->bi_iter.bi_size = KEY_SIZE(&v->key) << 9; bio->bi_opf = REQ_OP_READ | REQ_META; diff --git a/drivers/md/bcache/extents.c b/drivers/md/bcache/extents.c index f4658a1f37b8..d626ffcbecb9 100644 --- a/drivers/md/bcache/extents.c +++ b/drivers/md/bcache/extents.c @@ -50,7 +50,7 @@ static bool __ptr_invalid(struct cache_set *c, const struct bkey *k)

for (i = 0; i < KEY_PTRS(k); i++) if (ptr_available(c, k, i)) { - struct cache *ca = PTR_CACHE(c, k, i); + struct cache *ca = c->cache; size_t bucket = PTR_BUCKET_NR(c, k, i); size_t r = bucket_remainder(c, PTR_OFFSET(k, i));

@@ -71,7 +71,7 @@ static const char *bch_ptr_status(struct cache_set *c, const struct bkey *k)

for (i = 0; i < KEY_PTRS(k); i++) if (ptr_available(c, k, i)) { - struct cache *ca = PTR_CACHE(c, k, i); + struct cache *ca = c->cache; size_t bucket = PTR_BUCKET_NR(c, k, i); size_t r = bucket_remainder(c, PTR_OFFSET(k, i));

diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c index dad71a6b7889..e4388fe3ab7e 100644 --- a/drivers/md/bcache/io.c +++ b/drivers/md/bcache/io.c @@ -36,7 +36,7 @@ void __bch_submit_bbio(struct bio *bio, struct cache_set *c) struct bbio *b = container_of(bio, struct bbio, bio);

bio->bi_iter.bi_sector = PTR_OFFSET(&b->key, 0); - bio_set_dev(bio, PTR_CACHE(c, &b->key, 0)->bdev); + bio_set_dev(bio, c->cache->bdev);

b->submit_time_us = local_clock_us(); closure_bio_submit(c, bio, bio->bi_private); @@ -137,7 +137,7 @@ void bch_bbio_count_io_errors(struct cache_set *c, struct bio *bio, blk_status_t error, const char *m) { struct bbio *b = container_of(bio, struct bbio, bio); - struct cache *ca = PTR_CACHE(c, &b->key, 0); + struct cache *ca = c->cache; int is_read = (bio_data_dir(bio) == READ ? 1 : 0);

unsigned int threshold = op_is_write(bio_op(bio)) diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c index c6613e817333..de2c0d7699cf 100644 --- a/drivers/md/bcache/journal.c +++ b/drivers/md/bcache/journal.c @@ -768,7 +768,7 @@ static void journal_write_unlocked(struct closure *cl) w->data->csum = csum_set(w->data);

for (i = 0; i < KEY_PTRS(k); i++) { - ca = PTR_CACHE(c, k, i); + ca = c->cache; bio = &ca->journal.bio;

atomic_long_add(sectors, &ca->meta_sectors_written); diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 82d4e0880a99..bcd550a2b0da 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -416,7 +416,7 @@ static void read_dirty_endio(struct bio *bio) struct dirty_io *io = w->private;

/* is_read = 1 */ - bch_count_io_errors(PTR_CACHE(io->dc->disk.c, &w->key, 0), + bch_count_io_errors(io->dc->disk.c->cache, bio->bi_status, 1, "reading dirty data from cache");

@@ -510,8 +510,7 @@ static void read_dirty(struct cached_dev *dc) dirty_init(w); bio_set_op_attrs(&io->bio, REQ_OP_READ, 0); io->bio.bi_iter.bi_sector = PTR_OFFSET(&w->key, 0); - bio_set_dev(&io->bio, - PTR_CACHE(dc->disk.c, &w->key, 0)->bdev); + bio_set_dev(&io->bio, dc->disk.c->cache->bdev); io->bio.bi_end_io = read_dirty_endio;

if (bch_bio_alloc_pages(&io->bio, GFP_KERNEL))

From: Arnd Bergmann arnd@arndb.de

mainline inclusion from v5.13-rc1 commit be3bacececd7c4ab233105171d39082858de1baa category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

building with 'make W=1' shows a harmless warning for each user of the EBUG_ON() macro:

drivers/md/bcache/bset.c: In function 'bch_btree_sort_partial': drivers/md/bcache/util.h:30:55: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body] 30 | #define EBUG_ON(cond) do { if (cond); } while (0) | ^ drivers/md/bcache/bset.c:1312:9: note: in expansion of macro 'EBUG_ON' 1312 | EBUG_ON(oldsize >= 0 && bch_count_data(b) != oldsize); | ^~~~~~~

Reword the macro slightly to avoid the warning.

Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20210411134316.80274-5-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/util.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/bcache/util.h b/drivers/md/bcache/util.h index c029f7443190..bca4a7c97da7 100644 --- a/drivers/md/bcache/util.h +++ b/drivers/md/bcache/util.h @@ -27,7 +27,7 @@ struct closure;

#else /* DEBUG */

-#define EBUG_ON(cond) do { if (cond); } while (0) +#define EBUG_ON(cond) do { if (cond) do {} while (0); } while (0) #define atomic_dec_bug(v) atomic_dec(v) #define atomic_inc_bug(v, i) atomic_inc(v)

From: "Gustavo A. R. Silva" gustavoars@kernel.org

mainline inclusion from v5.13-rc1 commit 62594f189e81caffa6a3bfa2fdb08eec2e347c76 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

Cast multiple variables to (int64_t) in order to give the compiler complete information about the proper arithmetic to use. Notice that these variables are being used in contexts that expect expressions of type int64_t (64 bit, signed). And currently, such expressions are being evaluated using 32-bit arithmetic.

Fixes: d0cf9503e908 ("octeontx2-pf: ethtool fec mode support") Addresses-Coverity-ID: 1501724 ("Unintentional integer overflow") Addresses-Coverity-ID: 1501725 ("Unintentional integer overflow") Addresses-Coverity-ID: 1501726 ("Unintentional integer overflow") Signed-off-by: Gustavo A. R. Silva gustavoars@kernel.org Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20210411134316.80274-7-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/writeback.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index bcd550a2b0da..8120da278161 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -110,13 +110,13 @@ static void __update_writeback_rate(struct cached_dev *dc) int64_t fps;

if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID) { - fp_term = dc->writeback_rate_fp_term_low * + fp_term = (int64_t)dc->writeback_rate_fp_term_low * (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_LOW); } else if (c->gc_stats.in_use <= BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH) { - fp_term = dc->writeback_rate_fp_term_mid * + fp_term = (int64_t)dc->writeback_rate_fp_term_mid * (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_MID); } else { - fp_term = dc->writeback_rate_fp_term_high * + fp_term = (int64_t)dc->writeback_rate_fp_term_high * (c->gc_stats.in_use - BCH_WRITEBACK_FRAGMENT_THRESHOLD_HIGH); } fps = div_s64(dirty, dirty_buckets) * fp_term;

From: YueHaibing yuehaibing@huawei.com

mainline inclusion from v5.13-rc5 commit 415f0c835ba799e47ce077b01876568431da1ff3 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

Fix W=1 kernel build warning:

lib/crc64.c:40: warning: bad line: or the previous crc64 value if computing incrementally.

Link: https://lkml.kernel.org/r/20210601135851.15444-1-yuehaibing@huawei.com Signed-off-by: YueHaibing yuehaibing@huawei.com Reviewed-by: Coly Li colyli@suse.de Acked-by: Randy Dunlap rdunlap@infradead.org Tested-by: Randy Dunlap rdunlap@infradead.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org --- lib/crc64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/crc64.c b/lib/crc64.c index 47cfa054827f..9f852a89ee2a 100644 --- a/lib/crc64.c +++ b/lib/crc64.c @@ -37,7 +37,7 @@ MODULE_LICENSE("GPL v2"); /** * crc64_be - Calculate bitwise big-endian ECMA-182 CRC64 * @crc: seed value for computation. 0 or (u64)~0 for a new CRC calculation, - or the previous crc64 value if computing incrementally. + * or the previous crc64 value if computing incrementally. * @p: pointer to buffer over which CRC64 is run * @len: length of buffer @p */

mainline inclusion from v5.13-rc6 commit 41fe8d088e96472f63164e213de44ec77be69478 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

In the cache missing code path of cached device, if a proper location from the internal B+ tree is matched for a cache miss range, function cached_dev_cache_miss() will be called in cache_lookup_fn() in the following code block, [code block 1] 526 unsigned int sectors = KEY_INODE(k) == s->iop.inode 527 ? min_t(uint64_t, INT_MAX, 528 KEY_START(k) - bio->bi_iter.bi_sector) 529 : INT_MAX; 530 int ret = s->d->cache_miss(b, s, bio, sectors);

Here s->d->cache_miss() is the call backfunction pointer initialized as cached_dev_cache_miss(), the last parameter 'sectors' is an important hint to calculate the size of read request to backing device of the missing cache data.

Current calculation in above code block may generate oversized value of 'sectors', which consequently may trigger 2 different potential kernel panics by BUG() or BUG_ON() as listed below,

1) BUG_ON() inside bch_btree_insert_key(), [code block 2] 886 BUG_ON(b->ops->is_extents && !KEY_SIZE(k)); 2) BUG() inside biovec_slab(), [code block 3] 51 default: 52 BUG(); 53 return NULL;

All the above panics are original from cached_dev_cache_miss() by the oversized parameter 'sectors'.

Inside cached_dev_cache_miss(), parameter 'sectors' is used to calculate the size of data read from backing device for the cache missing. This size is stored in s->insert_bio_sectors by the following lines of code, [code block 4] 909 s->insert_bio_sectors = min(sectors, bio_sectors(bio) + reada);

Then the actual key inserting to the internal B+ tree is generated and stored in s->iop.replace_key by the following lines of code, [code block 5] 911 s->iop.replace_key = KEY(s->iop.inode, 912 bio->bi_iter.bi_sector + s->insert_bio_sectors, 913 s->insert_bio_sectors); The oversized parameter 'sectors' may trigger panic 1) by BUG_ON() from the above code block.

And the bio sending to backing device for the missing data is allocated with hint from s->insert_bio_sectors by the following lines of code, [code block 6] 926 cache_bio = bio_alloc_bioset(GFP_NOWAIT, 927 DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS), 928 &dc->disk.bio_split); The oversized parameter 'sectors' may trigger panic 2) by BUG() from the agove code block.

Now let me explain how the panics happen with the oversized 'sectors'. In code block 5, replace_key is generated by macro KEY(). From the definition of macro KEY(), [code block 7] 71 #define KEY(inode, offset, size) \ 72 ((struct bkey) { \ 73 .high = (1ULL << 63) | ((__u64) (size) << 20) | (inode), \ 74 .low = (offset) \ 75 })

Here 'size' is 16bits width embedded in 64bits member 'high' of struct bkey. But in code block 1, if "KEY_START(k) - bio->bi_iter.bi_sector" is very probably to be larger than (1<<16) - 1, which makes the bkey size calculation in code block 5 is overflowed. In one bug report the value of parameter 'sectors' is 131072 (= 1 << 17), the overflowed 'sectors' results the overflowed s->insert_bio_sectors in code block 4, then makes size field of s->iop.replace_key to be 0 in code block 5. Then the 0- sized s->iop.replace_key is inserted into the internal B+ tree as cache missing check key (a special key to detect and avoid a racing between normal write request and cache missing read request) as, [code block 8] 915 ret = bch_btree_insert_check_key(b, &s->op, &s->iop.replace_key);

Then the 0-sized s->iop.replace_key as 3rd parameter triggers the bkey size check BUG_ON() in code block 2, and causes the kernel panic 1).

Another kernel panic is from code block 6, is by the bvecs number oversized value s->insert_bio_sectors from code block 4, min(sectors, bio_sectors(bio) + reada) There are two possibility for oversized reresult, - bio_sectors(bio) is valid, but bio_sectors(bio) + reada is oversized. - sectors < bio_sectors(bio) + reada, but sectors is oversized.

From a bug report the result of "DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS)" from code block 6 can be 344, 282, 946, 342 and many other values which larther than BIO_MAX_VECS (a.k.a 256). When calling bio_alloc_bioset() with such larger-than-256 value as the 2nd parameter, this value will eventually be sent to biovec_slab() as parameter 'nr_vecs' in following code path, bio_alloc_bioset() ==> bvec_alloc() ==> biovec_slab() Because parameter 'nr_vecs' is larger-than-256 value, the panic by BUG() in code block 3 is triggered inside biovec_slab().

From the above analysis, we know that the 4th parameter 'sector' sent into cached_dev_cache_miss() may cause overflow in code block 5 and 6, and finally cause kernel panic in code block 2 and 3. And if result of bio_sectors(bio) + reada exceeds valid bvecs number, it may also trigger kernel panic in code block 3 from code block 6.

Now the almost-useless readahead size for cache missing request back to backing device is removed, this patch can fix the oversized issue with more simpler method. - add a local variable size_limit, set it by the minimum value from the max bkey size and max bio bvecs number. - set s->insert_bio_sectors by the minimum value from size_limit, sectors, and the sectors size of bio. - replace sectors by s->insert_bio_sectors to do bio_next_split.

By the above method with size_limit, s->insert_bio_sectors will never result oversized replace_key size or bio bvecs number. And split bio 'miss' from bio_next_split() will always match the size of 'cache_bio', that is the current maximum bio size we can sent to backing device for fetching the cache missing data.

Current problmatic code can be partially found since Linux v3.13-rc1, therefore all maintained stable kernels should try to apply this fix.

(Coly Li: still use BIO_MAX_PAGES because BIO_MAX_VECS is not defined yet in 5.10 based kernel.)

Reported-by: Alexander Ullrich ealex1979@gmail.com Reported-by: Diego Ercolani diego.ercolani@gmail.com Reported-by: Jan Szubiak jan.szubiak@linuxpolska.pl Reported-by: Marco Rebhan me@dblsaiko.net Reported-by: Matthias Ferdinand bcache@mfedv.net Reported-by: Victor Westerhuis victor@westerhu.is Reported-by: Vojtech Pavlik vojtech@suse.cz Reported-and-tested-by: Rolf Fokkens rolf@rolffokkens.nl Reported-and-tested-by: Thorsten Knabe linux@thorsten-knabe.de Signed-off-by: Coly Li colyli@suse.de Cc: stable@vger.kernel.org Cc: Christoph Hellwig hch@lst.de Cc: Kent Overstreet kent.overstreet@gmail.com Cc: Nix nix@esperi.org.uk Cc: Takashi Iwai tiwai@suse.com Link: https://lore.kernel.org/r/20210607125052.21277-3-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/request.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index f66889d882f5..19014a87a7db 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -880,6 +880,7 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s, int ret = MAP_CONTINUE; struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); struct bio *miss, *cache_bio; + unsigned int size_limit;

s->cache_missed = 1;

@@ -889,7 +890,10 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s, goto out_submit; }

- s->insert_bio_sectors = min(sectors, bio_sectors(bio)); + /* Limitation for valid replace key size and cache_bio bvecs number */ + size_limit = min_t(unsigned int, BIO_MAX_PAGES * PAGE_SECTORS, + (1 << KEY_SIZE_BITS) - 1); + s->insert_bio_sectors = min3(size_limit, sectors, bio_sectors(bio));

s->iop.replace_key = KEY(s->iop.inode, bio->bi_iter.bi_sector + s->insert_bio_sectors, @@ -901,7 +905,8 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s,

s->iop.replace = true;

- miss = bio_next_split(bio, sectors, GFP_NOIO, &s->d->bio_split); + miss = bio_next_split(bio, s->insert_bio_sectors, GFP_NOIO, + &s->d->bio_split);

/* btree_search_recurse()'s btree iterator is no good anymore */ ret = miss == bio ? MAP_DONE : -EINTR;

From: Chao Yu yuchao0@huawei.com

mainline inclusion from v5.16-rc1 commit d55f7cb2e5c053010d2b527494da9bbb722a78ba category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

In register_bcache(), there are several cases we didn't set correct error info (return value and/or error message): - if kzalloc() fails, it needs to return ENOMEM and print "cannot allocate memory"; - if register_cache() fails, it's better to propagate its return value rather than using default EINVAL.

Signed-off-by: Chao Yu yuchao0@huawei.com Reviewed-by: Hannes Reinecke hare@suse.de Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20211020143812.6403-4-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/super.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index ecdd613833f4..06f69970f836 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -2626,8 +2626,11 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, if (SB_IS_BDEV(sb)) { struct cached_dev *dc = kzalloc(sizeof(*dc), GFP_KERNEL);

- if (!dc) + if (!dc) { + ret = -ENOMEM; + err = "cannot allocate memory"; goto out_put_sb_page; + }

mutex_lock(&bch_register_lock); ret = register_bdev(sb, sb_disk, bdev, dc); @@ -2638,11 +2641,15 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, } else { struct cache *ca = kzalloc(sizeof(*ca), GFP_KERNEL);

- if (!ca) + if (!ca) { + ret = -ENOMEM; + err = "cannot allocate memory"; goto out_put_sb_page; + }

/* blkdev_put() will be called in bch_cache_release() */ - if (register_cache(sb, sb_disk, bdev, ca) != 0) + ret = register_cache(sb, sb_disk, bdev, ca); + if (ret) goto out_free_sb; }

mainline inclusion from v5.16-rc1 commit cf2197ca4b8c199d188593ca6800ea1827c42171 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

The header file include/uapi/linux/bcache.h is not really a user space API heaer. This file defines the ondisk format of bcache internal meta data but no one includes it from user space, bcache-tools has its own copy of this header with minor modification.

Therefore, this patch moves include/uapi/linux/bcache.h to bcache code directory as drivers/md/bcache/bcache_ondisk.h.

Suggested-by: Arnd Bergmann arnd@kernel.org Suggested-by: Christoph Hellwig hch@lst.de Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20211029060930.119923-2-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/bcache.h | 2 +- .../uapi/linux/bcache.h => drivers/md/bcache/bcache_ondisk.h | 0 drivers/md/bcache/bset.h | 2 +- drivers/md/bcache/features.c | 2 +- drivers/md/bcache/features.h | 3 ++- 5 files changed, 5 insertions(+), 4 deletions(-) rename include/uapi/linux/bcache.h => drivers/md/bcache/bcache_ondisk.h (100%)

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 5fc989a6d452..2a011469af02 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -178,7 +178,6 @@

#define pr_fmt(fmt) "bcache: %s() " fmt, __func__

-#include <linux/bcache.h> #include <linux/bio.h> #include <linux/kobject.h> #include <linux/list.h> @@ -190,6 +189,7 @@ #include <linux/workqueue.h> #include <linux/kthread.h>

+#include "bcache_ondisk.h" #include "bset.h" #include "util.h" #include "closure.h" diff --git a/include/uapi/linux/bcache.h b/drivers/md/bcache/bcache_ondisk.h similarity index 100% rename from include/uapi/linux/bcache.h rename to drivers/md/bcache/bcache_ondisk.h diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h index a50dcfda656f..d795c84246b0 100644 --- a/drivers/md/bcache/bset.h +++ b/drivers/md/bcache/bset.h @@ -2,10 +2,10 @@ #ifndef _BCACHE_BSET_H #define _BCACHE_BSET_H

-#include <linux/bcache.h> #include <linux/kernel.h> #include <linux/types.h>

+#include "bcache_ondisk.h" #include "util.h" /* for time_stats */

/* diff --git a/drivers/md/bcache/features.c b/drivers/md/bcache/features.c index 6d2b7b84a7b7..634922c5601d 100644 --- a/drivers/md/bcache/features.c +++ b/drivers/md/bcache/features.c @@ -6,7 +6,7 @@ * Copyright 2020 Coly Li colyli@suse.de * */ -#include <linux/bcache.h> +#include "bcache_ondisk.h" #include "bcache.h" #include "features.h"

diff --git a/drivers/md/bcache/features.h b/drivers/md/bcache/features.h index d1c8fd3977fc..09161b89c63e 100644 --- a/drivers/md/bcache/features.h +++ b/drivers/md/bcache/features.h @@ -2,10 +2,11 @@ #ifndef _BCACHE_FEATURES_H #define _BCACHE_FEATURES_H

-#include <linux/bcache.h> #include <linux/kernel.h> #include <linux/types.h>

+#include "bcache_ondisk.h" + #define BCH_FEATURE_COMPAT 0 #define BCH_FEATURE_RO_COMPAT 1 #define BCH_FEATURE_INCOMPAT 2

From: Lin Feng linf@wangsu.com

mainline inclusion from v5.16-rc6 commit aa97f6cdb7e92909e17c8ca63e622fcb81d57a57 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

Commit 0259d4498ba4 ("bcache: move calc_cached_dev_sectors to proper place on backing device detach") tries to fix calc_cached_dev_sectors when bcache device detaches, but now we have:

cached_dev_detach_finish ... bcache_device_detach(&dc->disk); ... closure_put(&d->c->caching); d->c = NULL; [*explicitly set dc->disk.c to NULL*] list_move(&dc->list, &uncached_devices); calc_cached_dev_sectors(dc->disk.c); [*passing a NULL pointer*] ...

Upper codeflows shows how bug happens, this patch fix the problem by caching dc->disk.c beforehand, and cache_set won't be freed under us because c->caching closure at least holds a reference count and closure callback __cache_set_unregister only being called by bch_cache_set_stop which using closure_queue(&c->caching), that means c->caching closure callback for destroying cache_set won't be trigger by previous closure_put(&d->c->caching). So at this stage(while cached_dev_detach_finish is calling) it's safe to access cache_set dc->disk.c.

Fixes: 0259d4498ba4 ("bcache: move calc_cached_dev_sectors to proper place on backing device detach") Signed-off-by: Lin Feng linf@wangsu.com Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20211112053629.3437-2-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/super.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 203f85599018..a98b46d3cd0b 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -1150,6 +1150,7 @@ static void cancel_writeback_rate_update_dwork(struct cached_dev *dc) static void cached_dev_detach_finish(struct work_struct *w) { struct cached_dev *dc = container_of(w, struct cached_dev, detach); + struct cache_set *c = dc->disk.c;

BUG_ON(!test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags)); BUG_ON(refcount_read(&dc->count)); @@ -1167,7 +1168,7 @@ static void cached_dev_detach_finish(struct work_struct *w)

bcache_device_detach(&dc->disk); list_move(&dc->list, &uncached_devices); - calc_cached_dev_sectors(dc->disk.c); + calc_cached_dev_sectors(c);

clear_bit(BCACHE_DEV_DETACHING, &dc->disk.flags); clear_bit(BCACHE_DEV_UNLINK_DONE, &dc->disk.flags);

From: Mingzhe Zou mingzhe.zou@easystack.cn

mainline inclusion from v5.18-rc1 commit 7b1002f7cfe581930f63787a0b3de0144e61ed55 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

When attaching a cached device (a.k.a backing device) to a cache device, bch_sectors_dirty_init() is called to count dirty sectors and stripes (see what bcache_dev_sectors_dirty_add() does) on the cache device.

When bcache_dev_sectors_dirty_add() is called, set_bit(stripe, d->full_dirty_stripes) or clear_bit(stripe, d->full_dirty_stripes) operation will always be performed. In full_dirty_stripes, each 1bit represents stripe_size (8192) sectors (512B), so 1bit=4MB (8192*512), and each CPU cache line=64B=512bit=2048MB. When 20 threads process a cached disk with 100G dirty data, a single thread processes about 23M at a time, and 20 threads total 460M. These full_dirty_stripes bits corresponding to the 460M data is likely to fall in the same CPU cache line. When one of these threads performs a set_bit or clear_bit operation, the same CPU cache line of other threads will become invalid and must read the full_dirty_stripes from the main memory again. Compared with single thread, the time of a bcache_dev_sectors_dirty_add() call is increased by about 50 times in our test (100G dirty data, 20 threads, bcache_dev_sectors_dirty_add() is called more than 20 million times).

This patch tries to test_bit before set_bit or clear_bit operation. Therefore, a lot of force set and clear operations will be avoided, and most of bcache_dev_sectors_dirty_add() calls will only read CPU cache line.

Signed-off-by: Mingzhe Zou mingzhe.zou@easystack.cn Signed-off-by: Coly Li colyli@suse.de --- drivers/md/bcache/writeback.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 8120da278161..e93a09ccaddd 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -585,10 +585,13 @@ void bcache_dev_sectors_dirty_add(struct cache_set *c, unsigned int inode,

sectors_dirty = atomic_add_return(s, d->stripe_sectors_dirty + stripe); - if (sectors_dirty == d->stripe_size) - set_bit(stripe, d->full_dirty_stripes); - else - clear_bit(stripe, d->full_dirty_stripes); + if (sectors_dirty == d->stripe_size) { + if (!test_bit(stripe, d->full_dirty_stripes)) + set_bit(stripe, d->full_dirty_stripes); + } else { + if (test_bit(stripe, d->full_dirty_stripes)) + clear_bit(stripe, d->full_dirty_stripes); + }

nr_sectors -= s; stripe_offset = 0;

mainline inclusion from v5.19-rc1 commit 622536443b6731ec82c563aae7807165adbe9178 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

Commit 8e7102273f59 ("bcache: make bch_btree_check() to be multithreaded") makes bch_btree_check() to be much faster when checking all btree nodes during cache device registration. But it isn't in ideal shap yet, still can be improved.

This patch does the following thing to improve current parallel btree nodes check by multiple threads in bch_btree_check(), - Add read lock to root node while checking all the btree nodes with multiple threads. Although currently it is not mandatory but it is good to have a read lock in code logic. - Remove local variable 'char name[32]', and generate kernel thread name string directly when calling kthread_run(). - Allocate local variable "struct btree_check_state check_state" on the stack and avoid unnecessary dynamic memory allocation for it. - Reduce BCH_BTR_CHKTHREAD_MAX from 64 to 12 which is enough indeed. - Increase check_state->started to count created kernel thread after it succeeds to create. - When wait for all checking kernel threads to finish, use wait_event() to replace wait_event_interruptible().

With this change, the code is more clear, and some potential error conditions are avoided.

Fixes: 8e7102273f59 ("bcache: make bch_btree_check() to be multithreaded") Signed-off-by: Coly Li colyli@suse.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220524102336.10684-2-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/btree.c | 58 ++++++++++++++++++--------------------- drivers/md/bcache/btree.h | 2 +- 2 files changed, 27 insertions(+), 33 deletions(-)

diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index 8eecc9df319b..7b6f8bfef927 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -2006,8 +2006,7 @@ int bch_btree_check(struct cache_set *c) int i; struct bkey *k = NULL; struct btree_iter iter; - struct btree_check_state *check_state; - char name[32]; + struct btree_check_state check_state;

/* check and mark root node keys */ for_each_key_filter(&c->root->keys, k, &iter, bch_ptr_invalid) @@ -2018,63 +2017,58 @@ int bch_btree_check(struct cache_set *c) if (c->root->level == 0) return 0;

- check_state = kzalloc(sizeof(struct btree_check_state), GFP_KERNEL); - if (!check_state) - return -ENOMEM; - - check_state->c = c; - check_state->total_threads = bch_btree_chkthread_nr(); - check_state->key_idx = 0; - spin_lock_init(&check_state->idx_lock); - atomic_set(&check_state->started, 0); - atomic_set(&check_state->enough, 0); - init_waitqueue_head(&check_state->wait); + check_state.c = c; + check_state.total_threads = bch_btree_chkthread_nr(); + check_state.key_idx = 0; + spin_lock_init(&check_state.idx_lock); + atomic_set(&check_state.started, 0); + atomic_set(&check_state.enough, 0); + init_waitqueue_head(&check_state.wait);

+ rw_lock(0, c->root, c->root->level); /* * Run multiple threads to check btree nodes in parallel, - * if check_state->enough is non-zero, it means current + * if check_state.enough is non-zero, it means current * running check threads are enough, unncessary to create * more. */ - for (i = 0; i < check_state->total_threads; i++) { - /* fetch latest check_state->enough earlier */ + for (i = 0; i < check_state.total_threads; i++) { + /* fetch latest check_state.enough earlier */ smp_mb__before_atomic(); - if (atomic_read(&check_state->enough)) + if (atomic_read(&check_state.enough)) break;

- check_state->infos[i].result = 0; - check_state->infos[i].state = check_state; - snprintf(name, sizeof(name), "bch_btrchk[%u]", i); - atomic_inc(&check_state->started); + check_state.infos[i].result = 0; + check_state.infos[i].state = &check_state;

- check_state->infos[i].thread = + check_state.infos[i].thread = kthread_run(bch_btree_check_thread, - &check_state->infos[i], - name); - if (IS_ERR(check_state->infos[i].thread)) { + &check_state.infos[i], + "bch_btrchk[%d]", i); + if (IS_ERR(check_state.infos[i].thread)) { pr_err("fails to run thread bch_btrchk[%d]\n", i); for (--i; i >= 0; i--) - kthread_stop(check_state->infos[i].thread); + kthread_stop(check_state.infos[i].thread); ret = -ENOMEM; goto out; } + atomic_inc(&check_state.started); }

/* * Must wait for all threads to stop. */ - wait_event_interruptible(check_state->wait, - atomic_read(&check_state->started) == 0); + wait_event(check_state.wait, atomic_read(&check_state.started) == 0);

- for (i = 0; i < check_state->total_threads; i++) { - if (check_state->infos[i].result) { - ret = check_state->infos[i].result; + for (i = 0; i < check_state.total_threads; i++) { + if (check_state.infos[i].result) { + ret = check_state.infos[i].result; goto out; } }

out: - kfree(check_state); + rw_unlock(0, c->root); return ret; }

diff --git a/drivers/md/bcache/btree.h b/drivers/md/bcache/btree.h index 50482107134f..1b5fdbc0d83e 100644 --- a/drivers/md/bcache/btree.h +++ b/drivers/md/bcache/btree.h @@ -226,7 +226,7 @@ struct btree_check_info { int result; };

-#define BCH_BTR_CHKTHREAD_MAX 64 +#define BCH_BTR_CHKTHREAD_MAX 12 struct btree_check_state { struct cache_set *c; int total_threads;

mainline inclusion from v5.19-rc1 commit 80db4e4707e78cb22287da7d058d7274bd4cb370 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

After making bch_sectors_dirty_init() being multithreaded, the existing incremental dirty sector counting in bch_root_node_dirty_init() doesn't release btree occupation after iterating 500000 (INIT_KEYS_EACH_TIME) bkeys. Because a read lock is added on btree root node to prevent the btree to be split during the dirty sectors counting, other I/O requester has no chance to gain the write lock even restart bcache_btree().

That is to say, the incremental dirty sectors counting is incompatible to the multhreaded bch_sectors_dirty_init(). We have to choose one and drop another one.

In my testing, with 512 bytes random writes, I generate 1.2T dirty data and a btree with 400K nodes. With single thread and incremental dirty sectors counting, it takes 30+ minites to register the backing device. And with multithreaded dirty sectors counting, the backing device registration can be accomplished within 2 minutes.

The 30+ minutes V.S. 2- minutes difference makes me decide to keep multithreaded bch_sectors_dirty_init() and drop the incremental dirty sectors counting. This is what this patch does.

But INIT_KEYS_EACH_TIME is kept, in sectors_dirty_init_fn() the CPU will be released by cond_resched() after every INIT_KEYS_EACH_TIME keys iterated. This is to avoid the watchdog reports a bogus soft lockup warning.

Fixes: b144e45fc576 ("bcache: make bch_sectors_dirty_init() to be multithreaded") Signed-off-by: Coly Li colyli@suse.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220524102336.10684-4-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/writeback.c | 41 +++++++++++------------------------ 1 file changed, 13 insertions(+), 28 deletions(-)

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 7ca91d1eb83b..2b6cb308f73a 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -805,13 +805,11 @@ static int bch_writeback_thread(void *arg)

/* Init */ #define INIT_KEYS_EACH_TIME 500000 -#define INIT_KEYS_SLEEP_MS 100

struct sectors_dirty_init { struct btree_op op; unsigned int inode; size_t count; - struct bkey start; };

static int sectors_dirty_init_fn(struct btree_op *_op, struct btree *b, @@ -827,11 +825,8 @@ static int sectors_dirty_init_fn(struct btree_op *_op, struct btree *b, KEY_START(k), KEY_SIZE(k));

op->count++; - if (atomic_read(&b->c->search_inflight) && - !(op->count % INIT_KEYS_EACH_TIME)) { - bkey_copy_key(&op->start, k); - return -EAGAIN; - } + if (!(op->count % INIT_KEYS_EACH_TIME)) + cond_resched();

return MAP_CONTINUE; } @@ -846,24 +841,16 @@ static int bch_root_node_dirty_init(struct cache_set *c, bch_btree_op_init(&op.op, -1); op.inode = d->id; op.count = 0; - op.start = KEY(op.inode, 0, 0); - - do { - ret = bcache_btree(map_keys_recurse, - k, - c->root, - &op.op, - &op.start, - sectors_dirty_init_fn, - 0); - if (ret == -EAGAIN) - schedule_timeout_interruptible( - msecs_to_jiffies(INIT_KEYS_SLEEP_MS)); - else if (ret < 0) { - pr_warn("sectors dirty init failed, ret=%d!\n", ret); - break; - } - } while (ret == -EAGAIN); + + ret = bcache_btree(map_keys_recurse, + k, + c->root, + &op.op, + &KEY(op.inode, 0, 0), + sectors_dirty_init_fn, + 0); + if (ret < 0) + pr_warn("sectors dirty init failed, ret=%d!\n", ret);

return ret; } @@ -907,7 +894,6 @@ static int bch_dirty_init_thread(void *arg) goto out; } skip_nr--; - cond_resched(); }

if (p) { @@ -917,7 +903,6 @@ static int bch_dirty_init_thread(void *arg)

p = NULL; prev_idx = cur_idx; - cond_resched(); }

out: @@ -956,11 +941,11 @@ void bch_sectors_dirty_init(struct bcache_device *d) bch_btree_op_init(&op.op, -1); op.inode = d->id; op.count = 0; - op.start = KEY(op.inode, 0, 0);

for_each_key_filter(&c->root->keys, k, &iter, bch_ptr_invalid) sectors_dirty_init_fn(&op.op, c->root, k); + rw_unlock(0, c->root); return; }

mainline inclusion from v5.19-rc1 commit 7d6b902ea0e02b2a25c480edf471cbaa4ebe6b3c category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

The local variables check_state (in bch_btree_check()) and state (in bch_sectors_dirty_init()) should be fully filled by 0, because before allocating them on stack, they were dynamically allocated by kzalloc().

Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20220527152818.27545-2-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/btree.c | 1 + drivers/md/bcache/writeback.c | 1 + 2 files changed, 2 insertions(+)

diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index 7b6f8bfef927..98daa9d200f7 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -2017,6 +2017,7 @@ int bch_btree_check(struct cache_set *c) if (c->root->level == 0) return 0;

+ memset(&check_state, 0, sizeof(struct btree_check_state)); check_state.c = c; check_state.total_threads = bch_btree_chkthread_nr(); check_state.key_idx = 0; diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 2b6cb308f73a..2bf831fe4ca4 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -950,6 +950,7 @@ void bch_sectors_dirty_init(struct bcache_device *d) return; }

+ memset(&state, 0, sizeof(struct bch_dirty_init_state)); state.c = c; state.d = d; state.total_threads = bch_btre_dirty_init_thread_nr();

mainline inclusion from v5.19-rc1 commit a1a2d8f0162b27e85e7ce0ae6a35c96a490e0559 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I59A5L?from=project-issue CVE: N/A

The kworker routine update_writeback_rate() is schedued to update the writeback rate in every 5 seconds by default. Before calling __update_writeback_rate() to do real job, semaphore dc->writeback_lock should be held by the kworker routine.

At the same time, bcache writeback thread routine bch_writeback_thread() also needs to hold dc->writeback_lock before flushing dirty data back into the backing device. If the dirty data set is large, it might be very long time for bch_writeback_thread() to scan all dirty buckets and releases dc->writeback_lock. In such case update_writeback_rate() can be starved for long enough time so that kernel reports a soft lockup warn- ing started like: watchdog: BUG: soft lockup - CPU#246 stuck for 23s! [kworker/246:31:179713]

Such soft lockup condition is unnecessary, because after the writeback thread finishes its job and releases dc->writeback_lock, the kworker update_writeback_rate() may continue to work and everything is fine indeed.

This patch avoids the unnecessary soft lockup by the following method, - Add new member to struct cached_dev - dc->rate_update_retry (0 by default) - In update_writeback_rate() call down_read_trylock(&dc->writeback_lock) firstly, if it fails then lock contention happens. - If dc->rate_update_retry <= BCH_WBRATE_UPDATE_MAX_SKIPS (15), doesn't acquire the lock and reschedules the kworker for next try. - If dc->rate_update_retry > BCH_WBRATE_UPDATE_MAX_SKIPS, no retry anymore and call down_read(&dc->writeback_lock) to wait for the lock.

By the above method, at worst case update_writeback_rate() may retry for 1+ minutes before blocking on dc->writeback_lock by calling down_read(). For a 4TB cache device with 1TB dirty data, 90%+ of the unnecessary soft lockup warning message can be avoided.

When retrying to acquire dc->writeback_lock in update_writeback_rate(), of course the writeback rate cannot be updated. It is fair, because when the kworker is blocked on the lock contention of dc->writeback_lock, the writeback rate cannot be updated neither.

This change follows Jens Axboe's suggestion to a more clear and simple version.

Signed-off-by: Coly Li colyli@suse.de Link: https://lore.kernel.org/r/20220528124550.32834-2-colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk --- drivers/md/bcache/bcache.h | 7 +++++++ drivers/md/bcache/writeback.c | 31 +++++++++++++++++++++---------- 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 2a011469af02..0563a40812fa 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -396,6 +396,13 @@ struct cached_dev { unsigned int error_limit; unsigned int offline_seconds;

+ /* + * Retry to update writeback_rate if contention happens for + * down_read(dc->writeback_lock) in update_writeback_rate() + */ +#define BCH_WBRATE_UPDATE_MAX_SKIPS 15 + unsigned int rate_update_retry; + char backing_dev_name[BDEVNAME_SIZE]; };

diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index 2bf831fe4ca4..3e879e985373 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -235,19 +235,27 @@ static void update_writeback_rate(struct work_struct *work) return; }

- if (atomic_read(&dc->has_dirty) && dc->writeback_percent) { - /* - * If the whole cache set is idle, set_at_max_writeback_rate() - * will set writeback rate to a max number. Then it is - * unncessary to update writeback rate for an idle cache set - * in maximum writeback rate number(s). - */ - if (!set_at_max_writeback_rate(c, dc)) { - down_read(&dc->writeback_lock); + /* + * If the whole cache set is idle, set_at_max_writeback_rate() + * will set writeback rate to a max number. Then it is + * unncessary to update writeback rate for an idle cache set + * in maximum writeback rate number(s). + */ + if (atomic_read(&dc->has_dirty) && dc->writeback_percent && + !set_at_max_writeback_rate(c, dc)) { + do { + if (!down_read_trylock((&dc->writeback_lock))) { + dc->rate_update_retry++; + if (dc->rate_update_retry <= + BCH_WBRATE_UPDATE_MAX_SKIPS) + break; + down_read(&dc->writeback_lock); + dc->rate_update_retry = 0; + } __update_writeback_rate(dc); update_gc_after_writeback(c); up_read(&dc->writeback_lock); - } + } while (0); }

@@ -1006,6 +1014,9 @@ void bch_cached_dev_writeback_init(struct cached_dev *dc) dc->writeback_rate_fp_term_high = 1000; dc->writeback_rate_i_term_inverse = 10000;

+ /* For dc->writeback_lock contention in update_writeback_rate() */ + dc->rate_update_retry = 0; + WARN_ON(test_and_clear_bit(BCACHE_DEV_WB_RUNNING, &dc->disk.flags)); INIT_DELAYED_WORK(&dc->writeback_rate_update, update_writeback_rate); }