From 4246a0b63bd8f56a1469b12eafeb875b1041a451 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 20 Jul 2015 15:29:37 +0200 Subject: block: add a bi_error field to struct bio Currently we have two different ways to signal an I/O error on a BIO: (1) by clearing the BIO_UPTODATE flag (2) by returning a Linux errno value to the bi_end_io callback The first one has the drawback of only communicating a single possible error (-EIO), and the second one has the drawback of not beeing persistent when bios are queued up, and are not passed along from child to parent bio in the ever more popular chaining scenario. Having both mechanisms available has the additional drawback of utterly confusing driver authors and introducing bugs where various I/O submitters only deal with one of them, and the others have to add boilerplate code to deal with both kinds of error returns. So add a new bi_error field to store an errno value directly in struct bio and remove the existing mechanisms to clean all this up. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: NeilBrown Signed-off-by: Jens Axboe --- drivers/md/bcache/request.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) (limited to 'drivers/md/bcache/request.c') diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index f292790997d7..a09b9462ff49 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -173,22 +173,22 @@ static void bch_data_insert_error(struct closure *cl) bch_data_insert_keys(cl); } -static void bch_data_insert_endio(struct bio *bio, int error) +static void bch_data_insert_endio(struct bio *bio) { struct closure *cl = bio->bi_private; struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); - if (error) { + if (bio->bi_error) { /* TODO: We could try to recover from this. */ if (op->writeback) - op->error = error; + op->error = bio->bi_error; else if (!op->replace) set_closure_fn(cl, bch_data_insert_error, op->wq); else set_closure_fn(cl, NULL, NULL); } - bch_bbio_endio(op->c, bio, error, "writing data to cache"); + bch_bbio_endio(op->c, bio, bio->bi_error, "writing data to cache"); } static void bch_data_insert_start(struct closure *cl) @@ -477,7 +477,7 @@ struct search { struct data_insert_op iop; }; -static void bch_cache_read_endio(struct bio *bio, int error) +static void bch_cache_read_endio(struct bio *bio) { struct bbio *b = container_of(bio, struct bbio, bio); struct closure *cl = bio->bi_private; @@ -490,15 +490,15 @@ static void bch_cache_read_endio(struct bio *bio, int error) * from the backing device. */ - if (error) - s->iop.error = error; + if (bio->bi_error) + s->iop.error = bio->bi_error; else if (!KEY_DIRTY(&b->key) && ptr_stale(s->iop.c, &b->key, 0)) { atomic_long_inc(&s->iop.c->cache_read_races); s->iop.error = -EINTR; } - bch_bbio_endio(s->iop.c, bio, error, "reading from cache"); + bch_bbio_endio(s->iop.c, bio, bio->bi_error, "reading from cache"); } /* @@ -591,13 +591,13 @@ static void cache_lookup(struct closure *cl) /* Common code for the make_request functions */ -static void request_endio(struct bio *bio, int error) +static void request_endio(struct bio *bio) { struct closure *cl = bio->bi_private; - if (error) { + if (bio->bi_error) { struct search *s = container_of(cl, struct search, cl); - s->iop.error = error; + s->iop.error = bio->bi_error; /* Only cache read errors are recoverable */ s->recoverable = false; } @@ -613,7 +613,8 @@ static void bio_complete(struct search *s) &s->d->disk->part0, s->start_time); trace_bcache_request_end(s->d, s->orig_bio); - bio_endio(s->orig_bio, s->iop.error); + s->orig_bio->bi_error = s->iop.error; + bio_endio(s->orig_bio); s->orig_bio = NULL; } } @@ -992,7 +993,7 @@ static void cached_dev_make_request(struct request_queue *q, struct bio *bio) } else { if ((bio->bi_rw & REQ_DISCARD) && !blk_queue_discard(bdev_get_queue(dc->bdev))) - bio_endio(bio, 0); + bio_endio(bio); else bch_generic_make_request(bio, &d->bio_split_hook); } -- cgit v1.2.3 From 749b61dab30736eb95b1ee23738cae90973d4fc3 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Sat, 23 Nov 2013 23:11:25 -0800 Subject: bcache: remove driver private bio splitting code The bcache driver has always accepted arbitrarily large bios and split them internally. Now that every driver must accept arbitrarily large bios this code isn't nessecary anymore. Cc: linux-bcache@vger.kernel.org Signed-off-by: Kent Overstreet [dpark: add more description in commit message] Signed-off-by: Dongsu Park Signed-off-by: Ming Lin Signed-off-by: Jens Axboe --- drivers/md/bcache/bcache.h | 18 -------- drivers/md/bcache/io.c | 101 +----------------------------------------- drivers/md/bcache/journal.c | 4 +- drivers/md/bcache/request.c | 16 +++---- drivers/md/bcache/super.c | 32 +------------ drivers/md/bcache/util.h | 5 ++- drivers/md/bcache/writeback.c | 4 +- 7 files changed, 18 insertions(+), 162 deletions(-) (limited to 'drivers/md/bcache/request.c') diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 04f7bc28ef83..6b420a55c745 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -243,19 +243,6 @@ struct keybuf { DECLARE_ARRAY_ALLOCATOR(struct keybuf_key, freelist, KEYBUF_NR); }; -struct bio_split_pool { - struct bio_set *bio_split; - mempool_t *bio_split_hook; -}; - -struct bio_split_hook { - struct closure cl; - struct bio_split_pool *p; - struct bio *bio; - bio_end_io_t *bi_end_io; - void *bi_private; -}; - struct bcache_device { struct closure cl; @@ -288,8 +275,6 @@ struct bcache_device { int (*cache_miss)(struct btree *, struct search *, struct bio *, unsigned); int (*ioctl) (struct bcache_device *, fmode_t, unsigned, unsigned long); - - struct bio_split_pool bio_split_hook; }; struct io { @@ -454,8 +439,6 @@ struct cache { atomic_long_t meta_sectors_written; atomic_long_t btree_sectors_written; atomic_long_t sectors_written; - - struct bio_split_pool bio_split_hook; }; struct gc_stat { @@ -873,7 +856,6 @@ void bch_bbio_endio(struct cache_set *, struct bio *, int, const char *); void bch_bbio_free(struct bio *, struct cache_set *); struct bio *bch_bbio_alloc(struct cache_set *); -void bch_generic_make_request(struct bio *, struct bio_split_pool *); void __bch_submit_bbio(struct bio *, struct cache_set *); void bch_submit_bbio(struct bio *, struct cache_set *, struct bkey *, unsigned); diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c index 9440df94bc83..86a0bb87124e 100644 --- a/drivers/md/bcache/io.c +++ b/drivers/md/bcache/io.c @@ -11,105 +11,6 @@ #include -static unsigned bch_bio_max_sectors(struct bio *bio) -{ - struct request_queue *q = bdev_get_queue(bio->bi_bdev); - struct bio_vec bv; - struct bvec_iter iter; - unsigned ret = 0, seg = 0; - - if (bio->bi_rw & REQ_DISCARD) - return min(bio_sectors(bio), q->limits.max_discard_sectors); - - bio_for_each_segment(bv, bio, iter) { - struct bvec_merge_data bvm = { - .bi_bdev = bio->bi_bdev, - .bi_sector = bio->bi_iter.bi_sector, - .bi_size = ret << 9, - .bi_rw = bio->bi_rw, - }; - - if (seg == min_t(unsigned, BIO_MAX_PAGES, - queue_max_segments(q))) - break; - - if (q->merge_bvec_fn && - q->merge_bvec_fn(q, &bvm, &bv) < (int) bv.bv_len) - break; - - seg++; - ret += bv.bv_len >> 9; - } - - ret = min(ret, queue_max_sectors(q)); - - WARN_ON(!ret); - ret = max_t(int, ret, bio_iovec(bio).bv_len >> 9); - - return ret; -} - -static void bch_bio_submit_split_done(struct closure *cl) -{ - struct bio_split_hook *s = container_of(cl, struct bio_split_hook, cl); - - s->bio->bi_end_io = s->bi_end_io; - s->bio->bi_private = s->bi_private; - bio_endio(s->bio); - - closure_debug_destroy(&s->cl); - mempool_free(s, s->p->bio_split_hook); -} - -static void bch_bio_submit_split_endio(struct bio *bio) -{ - struct closure *cl = bio->bi_private; - struct bio_split_hook *s = container_of(cl, struct bio_split_hook, cl); - - if (bio->bi_error) - s->bio->bi_error = bio->bi_error; - - bio_put(bio); - closure_put(cl); -} - -void bch_generic_make_request(struct bio *bio, struct bio_split_pool *p) -{ - struct bio_split_hook *s; - struct bio *n; - - if (!bio_has_data(bio) && !(bio->bi_rw & REQ_DISCARD)) - goto submit; - - if (bio_sectors(bio) <= bch_bio_max_sectors(bio)) - goto submit; - - s = mempool_alloc(p->bio_split_hook, GFP_NOIO); - closure_init(&s->cl, NULL); - - s->bio = bio; - s->p = p; - s->bi_end_io = bio->bi_end_io; - s->bi_private = bio->bi_private; - bio_get(bio); - - do { - n = bio_next_split(bio, bch_bio_max_sectors(bio), - GFP_NOIO, s->p->bio_split); - - n->bi_end_io = bch_bio_submit_split_endio; - n->bi_private = &s->cl; - - closure_get(&s->cl); - generic_make_request(n); - } while (n != bio); - - continue_at(&s->cl, bch_bio_submit_split_done, NULL); - return; -submit: - generic_make_request(bio); -} - /* Bios with headers */ void bch_bbio_free(struct bio *bio, struct cache_set *c) @@ -139,7 +40,7 @@ void __bch_submit_bbio(struct bio *bio, struct cache_set *c) bio->bi_bdev = PTR_CACHE(c, &b->key, 0)->bdev; b->submit_time_us = local_clock_us(); - closure_bio_submit(bio, bio->bi_private, PTR_CACHE(c, &b->key, 0)); + closure_bio_submit(bio, bio->bi_private); } void bch_submit_bbio(struct bio *bio, struct cache_set *c, diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c index d6a4e16030a6..29eba7219b01 100644 --- a/drivers/md/bcache/journal.c +++ b/drivers/md/bcache/journal.c @@ -61,7 +61,7 @@ reread: left = ca->sb.bucket_size - offset; bio->bi_private = &cl; bch_bio_map(bio, data); - closure_bio_submit(bio, &cl, ca); + closure_bio_submit(bio, &cl); closure_sync(&cl); /* This function could be simpler now since we no longer write @@ -648,7 +648,7 @@ static void journal_write_unlocked(struct closure *cl) spin_unlock(&c->journal.lock); while ((bio = bio_list_pop(&list))) - closure_bio_submit(bio, cl, c->cache[0]); + closure_bio_submit(bio, cl); continue_at(cl, journal_write_done, NULL); } diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c index a09b9462ff49..8e9877b04637 100644 --- a/drivers/md/bcache/request.c +++ b/drivers/md/bcache/request.c @@ -719,7 +719,7 @@ static void cached_dev_read_error(struct closure *cl) /* XXX: invalidate cache */ - closure_bio_submit(bio, cl, s->d); + closure_bio_submit(bio, cl); } continue_at(cl, cached_dev_cache_miss_done, NULL); @@ -842,7 +842,7 @@ static int cached_dev_cache_miss(struct btree *b, struct search *s, s->cache_miss = miss; s->iop.bio = cache_bio; bio_get(cache_bio); - closure_bio_submit(cache_bio, &s->cl, s->d); + closure_bio_submit(cache_bio, &s->cl); return ret; out_put: @@ -850,7 +850,7 @@ out_put: out_submit: miss->bi_end_io = request_endio; miss->bi_private = &s->cl; - closure_bio_submit(miss, &s->cl, s->d); + closure_bio_submit(miss, &s->cl); return ret; } @@ -915,7 +915,7 @@ static void cached_dev_write(struct cached_dev *dc, struct search *s) if (!(bio->bi_rw & REQ_DISCARD) || blk_queue_discard(bdev_get_queue(dc->bdev))) - closure_bio_submit(bio, cl, s->d); + closure_bio_submit(bio, cl); } else if (s->iop.writeback) { bch_writeback_add(dc); s->iop.bio = bio; @@ -930,12 +930,12 @@ static void cached_dev_write(struct cached_dev *dc, struct search *s) flush->bi_end_io = request_endio; flush->bi_private = cl; - closure_bio_submit(flush, cl, s->d); + closure_bio_submit(flush, cl); } } else { s->iop.bio = bio_clone_fast(bio, GFP_NOIO, dc->disk.bio_split); - closure_bio_submit(bio, cl, s->d); + closure_bio_submit(bio, cl); } closure_call(&s->iop.cl, bch_data_insert, NULL, cl); @@ -951,7 +951,7 @@ static void cached_dev_nodata(struct closure *cl) bch_journal_meta(s->iop.c, cl); /* If it's a flush, we send the flush to the backing device too */ - closure_bio_submit(bio, cl, s->d); + closure_bio_submit(bio, cl); continue_at(cl, cached_dev_bio_complete, NULL); } @@ -995,7 +995,7 @@ static void cached_dev_make_request(struct request_queue *q, struct bio *bio) !blk_queue_discard(bdev_get_queue(dc->bdev))) bio_endio(bio); else - bch_generic_make_request(bio, &d->bio_split_hook); + generic_make_request(bio); } } diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index be01fd3c87f1..679a093a3bf6 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -59,29 +59,6 @@ struct workqueue_struct *bcache_wq; #define BTREE_MAX_PAGES (256 * 1024 / PAGE_SIZE) -static void bio_split_pool_free(struct bio_split_pool *p) -{ - if (p->bio_split_hook) - mempool_destroy(p->bio_split_hook); - - if (p->bio_split) - bioset_free(p->bio_split); -} - -static int bio_split_pool_init(struct bio_split_pool *p) -{ - p->bio_split = bioset_create(4, 0); - if (!p->bio_split) - return -ENOMEM; - - p->bio_split_hook = mempool_create_kmalloc_pool(4, - sizeof(struct bio_split_hook)); - if (!p->bio_split_hook) - return -ENOMEM; - - return 0; -} - /* Superblock */ static const char *read_super(struct cache_sb *sb, struct block_device *bdev, @@ -537,7 +514,7 @@ static void prio_io(struct cache *ca, uint64_t bucket, unsigned long rw) bio->bi_private = ca; bch_bio_map(bio, ca->disk_buckets); - closure_bio_submit(bio, &ca->prio, ca); + closure_bio_submit(bio, &ca->prio); closure_sync(cl); } @@ -757,7 +734,6 @@ static void bcache_device_free(struct bcache_device *d) put_disk(d->disk); } - bio_split_pool_free(&d->bio_split_hook); if (d->bio_split) bioset_free(d->bio_split); kvfree(d->full_dirty_stripes); @@ -804,7 +780,6 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size, return minor; if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio))) || - bio_split_pool_init(&d->bio_split_hook) || !(d->disk = alloc_disk(1))) { ida_simple_remove(&bcache_minor, minor); return -ENOMEM; @@ -1793,8 +1768,6 @@ void bch_cache_release(struct kobject *kobj) ca->set->cache[ca->sb.nr_this_dev] = NULL; } - bio_split_pool_free(&ca->bio_split_hook); - free_pages((unsigned long) ca->disk_buckets, ilog2(bucket_pages(ca))); kfree(ca->prio_buckets); vfree(ca->buckets); @@ -1839,8 +1812,7 @@ static int cache_alloc(struct cache_sb *sb, struct cache *ca) ca->sb.nbuckets)) || !(ca->prio_buckets = kzalloc(sizeof(uint64_t) * prio_buckets(ca) * 2, GFP_KERNEL)) || - !(ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca)) || - bio_split_pool_init(&ca->bio_split_hook)) + !(ca->disk_buckets = alloc_bucket_pages(GFP_KERNEL, ca))) return -ENOMEM; ca->prio_last_buckets = ca->prio_buckets + prio_buckets(ca); diff --git a/drivers/md/bcache/util.h b/drivers/md/bcache/util.h index 1d04c4859c70..cf2cbc211d83 100644 --- a/drivers/md/bcache/util.h +++ b/drivers/md/bcache/util.h @@ -4,6 +4,7 @@ #include #include +#include #include #include #include @@ -570,10 +571,10 @@ static inline sector_t bdev_sectors(struct block_device *bdev) return bdev->bd_inode->i_size >> 9; } -#define closure_bio_submit(bio, cl, dev) \ +#define closure_bio_submit(bio, cl) \ do { \ closure_get(cl); \ - bch_generic_make_request(bio, &(dev)->bio_split_hook); \ + generic_make_request(bio); \ } while (0) uint64_t bch_crc64_update(uint64_t, const void *, size_t); diff --git a/drivers/md/bcache/writeback.c b/drivers/md/bcache/writeback.c index b4fc874c30fd..b23f88d9f18c 100644 --- a/drivers/md/bcache/writeback.c +++ b/drivers/md/bcache/writeback.c @@ -188,7 +188,7 @@ static void write_dirty(struct closure *cl) io->bio.bi_bdev = io->dc->bdev; io->bio.bi_end_io = dirty_endio; - closure_bio_submit(&io->bio, cl, &io->dc->disk); + closure_bio_submit(&io->bio, cl); continue_at(cl, write_dirty_finish, system_wq); } @@ -208,7 +208,7 @@ static void read_dirty_submit(struct closure *cl) { struct dirty_io *io = container_of(cl, struct dirty_io, cl); - closure_bio_submit(&io->bio, cl, &io->dc->disk); + closure_bio_submit(&io->bio, cl); continue_at(cl, write_dirty, system_wq); } -- cgit v1.2.3