diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-08 11:51:05 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-08 11:51:05 -0700 |
commit | ebb37277796269da36a8bc5d72ed1e8e1fb7d34b (patch) | |
tree | 0ded627a62a5cec70b18d12825dd858855c135d3 /drivers/md/bcache/journal.c | |
parent | 4de13d7aa8f4d02f4dc99d4609575659f92b3c5a (diff) | |
parent | f50efd2fdbd9b35b11f5778ed85beb764184bda9 (diff) | |
download | talos-op-linux-ebb37277796269da36a8bc5d72ed1e8e1fb7d34b.tar.gz talos-op-linux-ebb37277796269da36a8bc5d72ed1e8e1fb7d34b.zip |
Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
"It might look big in volume, but when categorized, not a lot of
drivers are touched. The pull request contains:
- mtip32xx fixes from Micron.
- A slew of drbd updates, this time in a nicer series.
- bcache, a flash/ssd caching framework from Kent.
- Fixes for cciss"
* 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits)
bcache: Use bd_link_disk_holder()
bcache: Allocator cleanup/fixes
cciss: bug fix to prevent cciss from loading in kdump crash kernel
cciss: add cciss_allow_hpsa module parameter
drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions
mtip32xx: Workaround for unaligned writes
bcache: Make sure blocksize isn't smaller than device blocksize
bcache: Fix merge_bvec_fn usage for when it modifies the bvm
bcache: Correctly check against BIO_MAX_PAGES
bcache: Hack around stuff that clones up to bi_max_vecs
bcache: Set ra_pages based on backing device's ra_pages
bcache: Take data offset from the bdev superblock.
mtip32xx: mtip32xx: Disable TRIM support
mtip32xx: fix a smatch warning
bcache: Disable broken btree fuzz tester
bcache: Fix a format string overflow
bcache: Fix a minor memory leak on device teardown
bcache: Documentation updates
bcache: Use WARN_ONCE() instead of __WARN()
bcache: Add missing #include <linux/prefetch.h>
...
Diffstat (limited to 'drivers/md/bcache/journal.c')
-rw-r--r-- | drivers/md/bcache/journal.c | 787 |
1 files changed, 787 insertions, 0 deletions
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c new file mode 100644 index 000000000000..8c8dfdcd9d4c --- /dev/null +++ b/drivers/md/bcache/journal.c @@ -0,0 +1,787 @@ +/* + * bcache journalling code, for btree insertions + * + * Copyright 2012 Google, Inc. + */ + +#include "bcache.h" +#include "btree.h" +#include "debug.h" +#include "request.h" + +/* + * Journal replay/recovery: + * + * This code is all driven from run_cache_set(); we first read the journal + * entries, do some other stuff, then we mark all the keys in the journal + * entries (same as garbage collection would), then we replay them - reinserting + * them into the cache in precisely the same order as they appear in the + * journal. + * + * We only journal keys that go in leaf nodes, which simplifies things quite a + * bit. + */ + +static void journal_read_endio(struct bio *bio, int error) +{ + struct closure *cl = bio->bi_private; + closure_put(cl); +} + +static int journal_read_bucket(struct cache *ca, struct list_head *list, + struct btree_op *op, unsigned bucket_index) +{ + struct journal_device *ja = &ca->journal; + struct bio *bio = &ja->bio; + + struct journal_replay *i; + struct jset *j, *data = ca->set->journal.w[0].data; + unsigned len, left, offset = 0; + int ret = 0; + sector_t bucket = bucket_to_sector(ca->set, ca->sb.d[bucket_index]); + + pr_debug("reading %llu", (uint64_t) bucket); + + while (offset < ca->sb.bucket_size) { +reread: left = ca->sb.bucket_size - offset; + len = min_t(unsigned, left, PAGE_SECTORS * 8); + + bio_reset(bio); + bio->bi_sector = bucket + offset; + bio->bi_bdev = ca->bdev; + bio->bi_rw = READ; + bio->bi_size = len << 9; + + bio->bi_end_io = journal_read_endio; + bio->bi_private = &op->cl; + bch_bio_map(bio, data); + + closure_bio_submit(bio, &op->cl, ca); + closure_sync(&op->cl); + + /* This function could be simpler now since we no longer write + * journal entries that overlap bucket boundaries; this means + * the start of a bucket will always have a valid journal entry + * if it has any journal entries at all. + */ + + j = data; + while (len) { + struct list_head *where; + size_t blocks, bytes = set_bytes(j); + + if (j->magic != jset_magic(ca->set)) + return ret; + + if (bytes > left << 9) + return ret; + + if (bytes > len << 9) + goto reread; + + if (j->csum != csum_set(j)) + return ret; + + blocks = set_blocks(j, ca->set); + + while (!list_empty(list)) { + i = list_first_entry(list, + struct journal_replay, list); + if (i->j.seq >= j->last_seq) + break; + list_del(&i->list); + kfree(i); + } + + list_for_each_entry_reverse(i, list, list) { + if (j->seq == i->j.seq) + goto next_set; + + if (j->seq < i->j.last_seq) + goto next_set; + + if (j->seq > i->j.seq) { + where = &i->list; + goto add; + } + } + + where = list; +add: + i = kmalloc(offsetof(struct journal_replay, j) + + bytes, GFP_KERNEL); + if (!i) + return -ENOMEM; + memcpy(&i->j, j, bytes); + list_add(&i->list, where); + ret = 1; + + ja->seq[bucket_index] = j->seq; +next_set: + offset += blocks * ca->sb.block_size; + len -= blocks * ca->sb.block_size; + j = ((void *) j) + blocks * block_bytes(ca); + } + } + + return ret; +} + +int bch_journal_read(struct cache_set *c, struct list_head *list, + struct btree_op *op) +{ +#define read_bucket(b) \ + ({ \ + int ret = journal_read_bucket(ca, list, op, b); \ + __set_bit(b, bitmap); \ + if (ret < 0) \ + return ret; \ + ret; \ + }) + + struct cache *ca; + unsigned iter; + + for_each_cache(ca, c, iter) { + struct journal_device *ja = &ca->journal; + unsigned long bitmap[SB_JOURNAL_BUCKETS / BITS_PER_LONG]; + unsigned i, l, r, m; + uint64_t seq; + + bitmap_zero(bitmap, SB_JOURNAL_BUCKETS); + pr_debug("%u journal buckets", ca->sb.njournal_buckets); + + /* Read journal buckets ordered by golden ratio hash to quickly + * find a sequence of buckets with valid journal entries + */ + for (i = 0; i < ca->sb.njournal_buckets; i++) { + l = (i * 2654435769U) % ca->sb.njournal_buckets; + + if (test_bit(l, bitmap)) + break; + + if (read_bucket(l)) + goto bsearch; + } + + /* If that fails, check all the buckets we haven't checked + * already + */ + pr_debug("falling back to linear search"); + + for (l = 0; l < ca->sb.njournal_buckets; l++) { + if (test_bit(l, bitmap)) + continue; + + if (read_bucket(l)) + goto bsearch; + } +bsearch: + /* Binary search */ + m = r = find_next_bit(bitmap, ca->sb.njournal_buckets, l + 1); + pr_debug("starting binary search, l %u r %u", l, r); + + while (l + 1 < r) { + m = (l + r) >> 1; + + if (read_bucket(m)) + l = m; + else + r = m; + } + + /* Read buckets in reverse order until we stop finding more + * journal entries + */ + pr_debug("finishing up"); + l = m; + + while (1) { + if (!l--) + l = ca->sb.njournal_buckets - 1; + + if (l == m) + break; + + if (test_bit(l, bitmap)) + continue; + + if (!read_bucket(l)) + break; + } + + seq = 0; + + for (i = 0; i < ca->sb.njournal_buckets; i++) + if (ja->seq[i] > seq) { + seq = ja->seq[i]; + ja->cur_idx = ja->discard_idx = + ja->last_idx = i; + + } + } + + c->journal.seq = list_entry(list->prev, + struct journal_replay, + list)->j.seq; + + return 0; +#undef read_bucket +} + +void bch_journal_mark(struct cache_set *c, struct list_head *list) +{ + atomic_t p = { 0 }; + struct bkey *k; + struct journal_replay *i; + struct journal *j = &c->journal; + uint64_t last = j->seq; + + /* + * journal.pin should never fill up - we never write a journal + * entry when it would fill up. But if for some reason it does, we + * iterate over the list in reverse order so that we can just skip that + * refcount instead of bugging. + */ + + list_for_each_entry_reverse(i, list, list) { + BUG_ON(last < i->j.seq); + i->pin = NULL; + + while (last-- != i->j.seq) + if (fifo_free(&j->pin) > 1) { + fifo_push_front(&j->pin, p); + atomic_set(&fifo_front(&j->pin), 0); + } + + if (fifo_free(&j->pin) > 1) { + fifo_push_front(&j->pin, p); + i->pin = &fifo_front(&j->pin); + atomic_set(i->pin, 1); + } + + for (k = i->j.start; + k < end(&i->j); + k = bkey_next(k)) { + unsigned j; + + for (j = 0; j < KEY_PTRS(k); j++) { + struct bucket *g = PTR_BUCKET(c, k, j); + atomic_inc(&g->pin); + + if (g->prio == BTREE_PRIO && + !ptr_stale(c, k, j)) + g->prio = INITIAL_PRIO; + } + + __bch_btree_mark_key(c, 0, k); + } + } +} + +int bch_journal_replay(struct cache_set *s, struct list_head *list, + struct btree_op *op) +{ + int ret = 0, keys = 0, entries = 0; + struct bkey *k; + struct journal_replay *i = + list_entry(list->prev, struct journal_replay, list); + + uint64_t start = i->j.last_seq, end = i->j.seq, n = start; + + list_for_each_entry(i, list, list) { + BUG_ON(i->pin && atomic_read(i->pin) != 1); + + if (n != i->j.seq) + pr_err( + "journal entries %llu-%llu missing! (replaying %llu-%llu)\n", + n, i->j.seq - 1, start, end); + + for (k = i->j.start; + k < end(&i->j); + k = bkey_next(k)) { + pr_debug("%s", pkey(k)); + bkey_copy(op->keys.top, k); + bch_keylist_push(&op->keys); + + op->journal = i->pin; + atomic_inc(op->journal); + + ret = bch_btree_insert(op, s); + if (ret) + goto err; + + BUG_ON(!bch_keylist_empty(&op->keys)); + keys++; + + cond_resched(); + } + + if (i->pin) + atomic_dec(i->pin); + n = i->j.seq + 1; + entries++; + } + + pr_info("journal replay done, %i keys in %i entries, seq %llu", + keys, entries, end); + + while (!list_empty(list)) { + i = list_first_entry(list, struct journal_replay, list); + list_del(&i->list); + kfree(i); + } +err: + closure_sync(&op->cl); + return ret; +} + +/* Journalling */ + +static void btree_flush_write(struct cache_set *c) +{ + /* + * Try to find the btree node with that references the oldest journal + * entry, best is our current candidate and is locked if non NULL: + */ + struct btree *b, *best = NULL; + unsigned iter; + + for_each_cached_btree(b, c, iter) { + if (!down_write_trylock(&b->lock)) + continue; + + if (!btree_node_dirty(b) || + !btree_current_write(b)->journal) { + rw_unlock(true, b); + continue; + } + + if (!best) + best = b; + else if (journal_pin_cmp(c, + btree_current_write(best), + btree_current_write(b))) { + rw_unlock(true, best); + best = b; + } else + rw_unlock(true, b); + } + + if (best) + goto out; + + /* We can't find the best btree node, just pick the first */ + list_for_each_entry(b, &c->btree_cache, list) + if (!b->level && btree_node_dirty(b)) { + best = b; + rw_lock(true, best, best->level); + goto found; + } + +out: + if (!best) + return; +found: + if (btree_node_dirty(best)) + bch_btree_write(best, true, NULL); + rw_unlock(true, best); +} + +#define last_seq(j) ((j)->seq - fifo_used(&(j)->pin) + 1) + +static void journal_discard_endio(struct bio *bio, int error) +{ + struct journal_device *ja = + container_of(bio, struct journal_device, discard_bio); + struct cache *ca = container_of(ja, struct cache, journal); + + atomic_set(&ja->discard_in_flight, DISCARD_DONE); + + closure_wake_up(&ca->set->journal.wait); + closure_put(&ca->set->cl); +} + +static void journal_discard_work(struct work_struct *work) +{ + struct journal_device *ja = + container_of(work, struct journal_device, discard_work); + + submit_bio(0, &ja->discard_bio); +} + +static void do_journal_discard(struct cache *ca) +{ + struct journal_device *ja = &ca->journal; + struct bio *bio = &ja->discard_bio; + + if (!ca->discard) { + ja->discard_idx = ja->last_idx; + return; + } + + switch (atomic_read(&ja->discard_in_flight) == DISCARD_IN_FLIGHT) { + case DISCARD_IN_FLIGHT: + return; + + case DISCARD_DONE: + ja->discard_idx = (ja->discard_idx + 1) % + ca->sb.njournal_buckets; + + atomic_set(&ja->discard_in_flight, DISCARD_READY); + /* fallthrough */ + + case DISCARD_READY: + if (ja->discard_idx == ja->last_idx) + return; + + atomic_set(&ja->discard_in_flight, DISCARD_IN_FLIGHT); + + bio_init(bio); + bio->bi_sector = bucket_to_sector(ca->set, + ca->sb.d[ja->discard_idx]); + bio->bi_bdev = ca->bdev; + bio->bi_rw = REQ_WRITE|REQ_DISCARD; + bio->bi_max_vecs = 1; + bio->bi_io_vec = bio->bi_inline_vecs; + bio->bi_size = bucket_bytes(ca); + bio->bi_end_io = journal_discard_endio; + + closure_get(&ca->set->cl); + INIT_WORK(&ja->discard_work, journal_discard_work); + schedule_work(&ja->discard_work); + } +} + +static void journal_reclaim(struct cache_set *c) +{ + struct bkey *k = &c->journal.key; + struct cache *ca; + uint64_t last_seq; + unsigned iter, n = 0; + atomic_t p; + + while (!atomic_read(&fifo_front(&c->journal.pin))) + fifo_pop(&c->journal.pin, p); + + last_seq = last_seq(&c->journal); + + /* Update last_idx */ + + for_each_cache(ca, c, iter) { + struct journal_device *ja = &ca->journal; + + while (ja->last_idx != ja->cur_idx && + ja->seq[ja->last_idx] < last_seq) + ja->last_idx = (ja->last_idx + 1) % + ca->sb.njournal_buckets; + } + + for_each_cache(ca, c, iter) + do_journal_discard(ca); + + if (c->journal.blocks_free) + return; + + /* + * Allocate: + * XXX: Sort by free journal space + */ + + for_each_cache(ca, c, iter) { + struct journal_device *ja = &ca->journal; + unsigned next = (ja->cur_idx + 1) % ca->sb.njournal_buckets; + + /* No space available on this device */ + if (next == ja->discard_idx) + continue; + + ja->cur_idx = next; + k->ptr[n++] = PTR(0, + bucket_to_sector(c, ca->sb.d[ja->cur_idx]), + ca->sb.nr_this_dev); + } + + bkey_init(k); + SET_KEY_PTRS(k, n); + + if (n) + c->journal.blocks_free = c->sb.bucket_size >> c->block_bits; + + if (!journal_full(&c->journal)) + __closure_wake_up(&c->journal.wait); +} + +void bch_journal_next(struct journal *j) +{ + atomic_t p = { 1 }; + + j->cur = (j->cur == j->w) + ? &j->w[1] + : &j->w[0]; + + /* + * The fifo_push() needs to happen at the same time as j->seq is + * incremented for last_seq() to be calculated correctly + */ + BUG_ON(!fifo_push(&j->pin, p)); + atomic_set(&fifo_back(&j->pin), 1); + + j->cur->data->seq = ++j->seq; + j->cur->need_write = false; + j->cur->data->keys = 0; + + if (fifo_full(&j->pin)) + pr_debug("journal_pin full (%zu)", fifo_used(&j->pin)); +} + +static void journal_write_endio(struct bio *bio, int error) +{ + struct journal_write *w = bio->bi_private; + + cache_set_err_on(error, w->c, "journal io error"); + closure_put(&w->c->journal.io.cl); +} + +static void journal_write(struct closure *); + +static void journal_write_done(struct closure *cl) +{ + struct journal *j = container_of(cl, struct journal, io.cl); + struct cache_set *c = container_of(j, struct cache_set, journal); + + struct journal_write *w = (j->cur == j->w) + ? &j->w[1] + : &j->w[0]; + + __closure_wake_up(&w->wait); + + if (c->journal_delay_ms) + closure_delay(&j->io, msecs_to_jiffies(c->journal_delay_ms)); + + continue_at(cl, journal_write, system_wq); +} + +static void journal_write_unlocked(struct closure *cl) + __releases(c->journal.lock) +{ + struct cache_set *c = container_of(cl, struct cache_set, journal.io.cl); + struct cache *ca; + struct journal_write *w = c->journal.cur; + struct bkey *k = &c->journal.key; + unsigned i, sectors = set_blocks(w->data, c) * c->sb.block_size; + + struct bio *bio; + struct bio_list list; + bio_list_init(&list); + + if (!w->need_write) { + /* + * XXX: have to unlock closure before we unlock journal lock, + * else we race with bch_journal(). But this way we race + * against cache set unregister. Doh. + */ + set_closure_fn(cl, NULL, NULL); + closure_sub(cl, CLOSURE_RUNNING + 1); + spin_unlock(&c->journal.lock); + return; + } else if (journal_full(&c->journal)) { + journal_reclaim(c); + spin_unlock(&c->journal.lock); + + btree_flush_write(c); + continue_at(cl, journal_write, system_wq); + } + + c->journal.blocks_free -= set_blocks(w->data, c); + + w->data->btree_level = c->root->level; + + bkey_copy(&w->data->btree_root, &c->root->key); + bkey_copy(&w->data->uuid_bucket, &c->uuid_bucket); + + for_each_cache(ca, c, i) + w->data->prio_bucket[ca->sb.nr_this_dev] = ca->prio_buckets[0]; + + w->data->magic = jset_magic(c); + w->data->version = BCACHE_JSET_VERSION; + w->data->last_seq = last_seq(&c->journal); + w->data->csum = csum_set(w->data); + + for (i = 0; i < KEY_PTRS(k); i++) { + ca = PTR_CACHE(c, k, i); + bio = &ca->journal.bio; + + atomic_long_add(sectors, &ca->meta_sectors_written); + + bio_reset(bio); + bio->bi_sector = PTR_OFFSET(k, i); + bio->bi_bdev = ca->bdev; + bio->bi_rw = REQ_WRITE|REQ_SYNC|REQ_META|REQ_FLUSH; + bio->bi_size = sectors << 9; + + bio->bi_end_io = journal_write_endio; + bio->bi_private = w; + bch_bio_map(bio, w->data); + + trace_bcache_journal_write(bio); + bio_list_add(&list, bio); + + SET_PTR_OFFSET(k, i, PTR_OFFSET(k, i) + sectors); + + ca->journal.seq[ca->journal.cur_idx] = w->data->seq; + } + + atomic_dec_bug(&fifo_back(&c->journal.pin)); + bch_journal_next(&c->journal); + journal_reclaim(c); + + spin_unlock(&c->journal.lock); + + while ((bio = bio_list_pop(&list))) + closure_bio_submit(bio, cl, c->cache[0]); + + continue_at(cl, journal_write_done, NULL); +} + +static void journal_write(struct closure *cl) +{ + struct cache_set *c = container_of(cl, struct cache_set, journal.io.cl); + + spin_lock(&c->journal.lock); + journal_write_unlocked(cl); +} + +static void __journal_try_write(struct cache_set *c, bool noflush) + __releases(c->journal.lock) +{ + struct closure *cl = &c->journal.io.cl; + + if (!closure_trylock(cl, &c->cl)) + spin_unlock(&c->journal.lock); + else if (noflush && journal_full(&c->journal)) { + spin_unlock(&c->journal.lock); + continue_at(cl, journal_write, system_wq); + } else + journal_write_unlocked(cl); +} + +#define journal_try_write(c) __journal_try_write(c, false) + +void bch_journal_meta(struct cache_set *c, struct closure *cl) +{ + struct journal_write *w; + + if (CACHE_SYNC(&c->sb)) { + spin_lock(&c->journal.lock); + + w = c->journal.cur; + w->need_write = true; + + if (cl) + BUG_ON(!closure_wait(&w->wait, cl)); + + __journal_try_write(c, true); + } +} + +/* + * Entry point to the journalling code - bio_insert() and btree_invalidate() + * pass bch_journal() a list of keys to be journalled, and then + * bch_journal() hands those same keys off to btree_insert_async() + */ + +void bch_journal(struct closure *cl) +{ + struct btree_op *op = container_of(cl, struct btree_op, cl); + struct cache_set *c = op->c; + struct journal_write *w; + size_t b, n = ((uint64_t *) op->keys.top) - op->keys.list; + + if (op->type != BTREE_INSERT || + !CACHE_SYNC(&c->sb)) + goto out; + + /* + * If we're looping because we errored, might already be waiting on + * another journal write: + */ + while (atomic_read(&cl->parent->remaining) & CLOSURE_WAITING) + closure_sync(cl->parent); + + spin_lock(&c->journal.lock); + + if (journal_full(&c->journal)) { + /* XXX: tracepoint */ + closure_wait(&c->journal.wait, cl); + + journal_reclaim(c); + spin_unlock(&c->journal.lock); + + btree_flush_write(c); + continue_at(cl, bch_journal, bcache_wq); + } + + w = c->journal.cur; + w->need_write = true; + b = __set_blocks(w->data, w->data->keys + n, c); + + if (b * c->sb.block_size > PAGE_SECTORS << JSET_BITS || + b > c->journal.blocks_free) { + /* XXX: If we were inserting so many keys that they won't fit in + * an _empty_ journal write, we'll deadlock. For now, handle + * this in bch_keylist_realloc() - but something to think about. + */ + BUG_ON(!w->data->keys); + + /* XXX: tracepoint */ + BUG_ON(!closure_wait(&w->wait, cl)); + + closure_flush(&c->journal.io); + + journal_try_write(c); + continue_at(cl, bch_journal, bcache_wq); + } + + memcpy(end(w->data), op->keys.list, n * sizeof(uint64_t)); + w->data->keys += n; + + op->journal = &fifo_back(&c->journal.pin); + atomic_inc(op->journal); + + if (op->flush_journal) { + closure_flush(&c->journal.io); + closure_wait(&w->wait, cl->parent); + } + + journal_try_write(c); +out: + bch_btree_insert_async(cl); +} + +void bch_journal_free(struct cache_set *c) +{ + free_pages((unsigned long) c->journal.w[1].data, JSET_BITS); + free_pages((unsigned long) c->journal.w[0].data, JSET_BITS); + free_fifo(&c->journal.pin); +} + +int bch_journal_alloc(struct cache_set *c) +{ + struct journal *j = &c->journal; + + closure_init_unlocked(&j->io); + spin_lock_init(&j->lock); + + c->journal_delay_ms = 100; + + j->w[0].c = c; + j->w[1].c = c; + + if (!(init_fifo(&j->pin, JOURNAL_PIN, GFP_KERNEL)) || + !(j->w[0].data = (void *) __get_free_pages(GFP_KERNEL, JSET_BITS)) || + !(j->w[1].data = (void *) __get_free_pages(GFP_KERNEL, JSET_BITS))) + return -ENOMEM; + + return 0; +} |