mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1344 lines
34 KiB
1344 lines
34 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* Main bcache entry point - handle a read or a write request and decide what to |
|
* do with it; the make_request functions are called by the block layer. |
|
* |
|
* Copyright 2010, 2011 Kent Overstreet <[email protected]> |
|
* Copyright 2012 Google, Inc. |
|
*/ |
|
|
|
#include "bcache.h" |
|
#include "btree.h" |
|
#include "debug.h" |
|
#include "request.h" |
|
#include "writeback.h" |
|
|
|
#include <linux/module.h> |
|
#include <linux/hash.h> |
|
#include <linux/random.h> |
|
#include <linux/backing-dev.h> |
|
|
|
#include <trace/events/bcache.h> |
|
|
|
#define CUTOFF_CACHE_ADD 95 |
|
#define CUTOFF_CACHE_READA 90 |
|
|
|
struct kmem_cache *bch_search_cache; |
|
|
|
static void bch_data_insert_start(struct closure *cl); |
|
|
|
static unsigned int cache_mode(struct cached_dev *dc) |
|
{ |
|
return BDEV_CACHE_MODE(&dc->sb); |
|
} |
|
|
|
static bool verify(struct cached_dev *dc) |
|
{ |
|
return dc->verify; |
|
} |
|
|
|
static void bio_csum(struct bio *bio, struct bkey *k) |
|
{ |
|
struct bio_vec bv; |
|
struct bvec_iter iter; |
|
uint64_t csum = 0; |
|
|
|
bio_for_each_segment(bv, bio, iter) { |
|
void *d = kmap(bv.bv_page) + bv.bv_offset; |
|
|
|
csum = bch_crc64_update(csum, d, bv.bv_len); |
|
kunmap(bv.bv_page); |
|
} |
|
|
|
k->ptr[KEY_PTRS(k)] = csum & (~0ULL >> 1); |
|
} |
|
|
|
/* Insert data into cache */ |
|
|
|
static void bch_data_insert_keys(struct closure *cl) |
|
{ |
|
struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
|
atomic_t *journal_ref = NULL; |
|
struct bkey *replace_key = op->replace ? &op->replace_key : NULL; |
|
int ret; |
|
|
|
if (!op->replace) |
|
journal_ref = bch_journal(op->c, &op->insert_keys, |
|
op->flush_journal ? cl : NULL); |
|
|
|
ret = bch_btree_insert(op->c, &op->insert_keys, |
|
journal_ref, replace_key); |
|
if (ret == -ESRCH) { |
|
op->replace_collision = true; |
|
} else if (ret) { |
|
op->status = BLK_STS_RESOURCE; |
|
op->insert_data_done = true; |
|
} |
|
|
|
if (journal_ref) |
|
atomic_dec_bug(journal_ref); |
|
|
|
if (!op->insert_data_done) { |
|
continue_at(cl, bch_data_insert_start, op->wq); |
|
return; |
|
} |
|
|
|
bch_keylist_free(&op->insert_keys); |
|
closure_return(cl); |
|
} |
|
|
|
static int bch_keylist_realloc(struct keylist *l, unsigned int u64s, |
|
struct cache_set *c) |
|
{ |
|
size_t oldsize = bch_keylist_nkeys(l); |
|
size_t newsize = oldsize + u64s; |
|
|
|
/* |
|
* The journalling code doesn't handle the case where the keys to insert |
|
* is bigger than an empty write: If we just return -ENOMEM here, |
|
* bch_data_insert_keys() will insert the keys created so far |
|
* and finish the rest when the keylist is empty. |
|
*/ |
|
if (newsize * sizeof(uint64_t) > block_bytes(c->cache) - sizeof(struct jset)) |
|
return -ENOMEM; |
|
|
|
return __bch_keylist_realloc(l, u64s); |
|
} |
|
|
|
static void bch_data_invalidate(struct closure *cl) |
|
{ |
|
struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
|
struct bio *bio = op->bio; |
|
|
|
pr_debug("invalidating %i sectors from %llu\n", |
|
bio_sectors(bio), (uint64_t) bio->bi_iter.bi_sector); |
|
|
|
while (bio_sectors(bio)) { |
|
unsigned int sectors = min(bio_sectors(bio), |
|
1U << (KEY_SIZE_BITS - 1)); |
|
|
|
if (bch_keylist_realloc(&op->insert_keys, 2, op->c)) |
|
goto out; |
|
|
|
bio->bi_iter.bi_sector += sectors; |
|
bio->bi_iter.bi_size -= sectors << 9; |
|
|
|
bch_keylist_add(&op->insert_keys, |
|
&KEY(op->inode, |
|
bio->bi_iter.bi_sector, |
|
sectors)); |
|
} |
|
|
|
op->insert_data_done = true; |
|
/* get in bch_data_insert() */ |
|
bio_put(bio); |
|
out: |
|
continue_at(cl, bch_data_insert_keys, op->wq); |
|
} |
|
|
|
static void bch_data_insert_error(struct closure *cl) |
|
{ |
|
struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
|
|
|
/* |
|
* Our data write just errored, which means we've got a bunch of keys to |
|
* insert that point to data that wasn't successfully written. |
|
* |
|
* We don't have to insert those keys but we still have to invalidate |
|
* that region of the cache - so, if we just strip off all the pointers |
|
* from the keys we'll accomplish just that. |
|
*/ |
|
|
|
struct bkey *src = op->insert_keys.keys, *dst = op->insert_keys.keys; |
|
|
|
while (src != op->insert_keys.top) { |
|
struct bkey *n = bkey_next(src); |
|
|
|
SET_KEY_PTRS(src, 0); |
|
memmove(dst, src, bkey_bytes(src)); |
|
|
|
dst = bkey_next(dst); |
|
src = n; |
|
} |
|
|
|
op->insert_keys.top = dst; |
|
|
|
bch_data_insert_keys(cl); |
|
} |
|
|
|
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 (bio->bi_status) { |
|
/* TODO: We could try to recover from this. */ |
|
if (op->writeback) |
|
op->status = bio->bi_status; |
|
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, bio->bi_status, "writing data to cache"); |
|
} |
|
|
|
static void bch_data_insert_start(struct closure *cl) |
|
{ |
|
struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
|
struct bio *bio = op->bio, *n; |
|
|
|
if (op->bypass) |
|
return bch_data_invalidate(cl); |
|
|
|
if (atomic_sub_return(bio_sectors(bio), &op->c->sectors_to_gc) < 0) |
|
wake_up_gc(op->c); |
|
|
|
/* |
|
* Journal writes are marked REQ_PREFLUSH; if the original write was a |
|
* flush, it'll wait on the journal write. |
|
*/ |
|
bio->bi_opf &= ~(REQ_PREFLUSH|REQ_FUA); |
|
|
|
do { |
|
unsigned int i; |
|
struct bkey *k; |
|
struct bio_set *split = &op->c->bio_split; |
|
|
|
/* 1 for the device pointer and 1 for the chksum */ |
|
if (bch_keylist_realloc(&op->insert_keys, |
|
3 + (op->csum ? 1 : 0), |
|
op->c)) { |
|
continue_at(cl, bch_data_insert_keys, op->wq); |
|
return; |
|
} |
|
|
|
k = op->insert_keys.top; |
|
bkey_init(k); |
|
SET_KEY_INODE(k, op->inode); |
|
SET_KEY_OFFSET(k, bio->bi_iter.bi_sector); |
|
|
|
if (!bch_alloc_sectors(op->c, k, bio_sectors(bio), |
|
op->write_point, op->write_prio, |
|
op->writeback)) |
|
goto err; |
|
|
|
n = bio_next_split(bio, KEY_SIZE(k), GFP_NOIO, split); |
|
|
|
n->bi_end_io = bch_data_insert_endio; |
|
n->bi_private = cl; |
|
|
|
if (op->writeback) { |
|
SET_KEY_DIRTY(k, true); |
|
|
|
for (i = 0; i < KEY_PTRS(k); i++) |
|
SET_GC_MARK(PTR_BUCKET(op->c, k, i), |
|
GC_MARK_DIRTY); |
|
} |
|
|
|
SET_KEY_CSUM(k, op->csum); |
|
if (KEY_CSUM(k)) |
|
bio_csum(n, k); |
|
|
|
trace_bcache_cache_insert(k); |
|
bch_keylist_push(&op->insert_keys); |
|
|
|
bio_set_op_attrs(n, REQ_OP_WRITE, 0); |
|
bch_submit_bbio(n, op->c, k, 0); |
|
} while (n != bio); |
|
|
|
op->insert_data_done = true; |
|
continue_at(cl, bch_data_insert_keys, op->wq); |
|
return; |
|
err: |
|
/* bch_alloc_sectors() blocks if s->writeback = true */ |
|
BUG_ON(op->writeback); |
|
|
|
/* |
|
* But if it's not a writeback write we'd rather just bail out if |
|
* there aren't any buckets ready to write to - it might take awhile and |
|
* we might be starving btree writes for gc or something. |
|
*/ |
|
|
|
if (!op->replace) { |
|
/* |
|
* Writethrough write: We can't complete the write until we've |
|
* updated the index. But we don't want to delay the write while |
|
* we wait for buckets to be freed up, so just invalidate the |
|
* rest of the write. |
|
*/ |
|
op->bypass = true; |
|
return bch_data_invalidate(cl); |
|
} else { |
|
/* |
|
* From a cache miss, we can just insert the keys for the data |
|
* we have written or bail out if we didn't do anything. |
|
*/ |
|
op->insert_data_done = true; |
|
bio_put(bio); |
|
|
|
if (!bch_keylist_empty(&op->insert_keys)) |
|
continue_at(cl, bch_data_insert_keys, op->wq); |
|
else |
|
closure_return(cl); |
|
} |
|
} |
|
|
|
/** |
|
* bch_data_insert - stick some data in the cache |
|
* @cl: closure pointer. |
|
* |
|
* This is the starting point for any data to end up in a cache device; it could |
|
* be from a normal write, or a writeback write, or a write to a flash only |
|
* volume - it's also used by the moving garbage collector to compact data in |
|
* mostly empty buckets. |
|
* |
|
* It first writes the data to the cache, creating a list of keys to be inserted |
|
* (if the data had to be fragmented there will be multiple keys); after the |
|
* data is written it calls bch_journal, and after the keys have been added to |
|
* the next journal write they're inserted into the btree. |
|
* |
|
* It inserts the data in op->bio; bi_sector is used for the key offset, |
|
* and op->inode is used for the key inode. |
|
* |
|
* If op->bypass is true, instead of inserting the data it invalidates the |
|
* region of the cache represented by op->bio and op->inode. |
|
*/ |
|
void bch_data_insert(struct closure *cl) |
|
{ |
|
struct data_insert_op *op = container_of(cl, struct data_insert_op, cl); |
|
|
|
trace_bcache_write(op->c, op->inode, op->bio, |
|
op->writeback, op->bypass); |
|
|
|
bch_keylist_init(&op->insert_keys); |
|
bio_get(op->bio); |
|
bch_data_insert_start(cl); |
|
} |
|
|
|
/* |
|
* Congested? Return 0 (not congested) or the limit (in sectors) |
|
* beyond which we should bypass the cache due to congestion. |
|
*/ |
|
unsigned int bch_get_congested(const struct cache_set *c) |
|
{ |
|
int i; |
|
|
|
if (!c->congested_read_threshold_us && |
|
!c->congested_write_threshold_us) |
|
return 0; |
|
|
|
i = (local_clock_us() - c->congested_last_us) / 1024; |
|
if (i < 0) |
|
return 0; |
|
|
|
i += atomic_read(&c->congested); |
|
if (i >= 0) |
|
return 0; |
|
|
|
i += CONGESTED_MAX; |
|
|
|
if (i > 0) |
|
i = fract_exp_two(i, 6); |
|
|
|
i -= hweight32(get_random_u32()); |
|
|
|
return i > 0 ? i : 1; |
|
} |
|
|
|
static void add_sequential(struct task_struct *t) |
|
{ |
|
ewma_add(t->sequential_io_avg, |
|
t->sequential_io, 8, 0); |
|
|
|
t->sequential_io = 0; |
|
} |
|
|
|
static struct hlist_head *iohash(struct cached_dev *dc, uint64_t k) |
|
{ |
|
return &dc->io_hash[hash_64(k, RECENT_IO_BITS)]; |
|
} |
|
|
|
static bool check_should_bypass(struct cached_dev *dc, struct bio *bio) |
|
{ |
|
struct cache_set *c = dc->disk.c; |
|
unsigned int mode = cache_mode(dc); |
|
unsigned int sectors, congested; |
|
struct task_struct *task = current; |
|
struct io *i; |
|
|
|
if (test_bit(BCACHE_DEV_DETACHING, &dc->disk.flags) || |
|
c->gc_stats.in_use > CUTOFF_CACHE_ADD || |
|
(bio_op(bio) == REQ_OP_DISCARD)) |
|
goto skip; |
|
|
|
if (mode == CACHE_MODE_NONE || |
|
(mode == CACHE_MODE_WRITEAROUND && |
|
op_is_write(bio_op(bio)))) |
|
goto skip; |
|
|
|
/* |
|
* If the bio is for read-ahead or background IO, bypass it or |
|
* not depends on the following situations, |
|
* - If the IO is for meta data, always cache it and no bypass |
|
* - If the IO is not meta data, check dc->cache_reada_policy, |
|
* BCH_CACHE_READA_ALL: cache it and not bypass |
|
* BCH_CACHE_READA_META_ONLY: not cache it and bypass |
|
* That is, read-ahead request for metadata always get cached |
|
* (eg, for gfs2 or xfs). |
|
*/ |
|
if ((bio->bi_opf & (REQ_RAHEAD|REQ_BACKGROUND))) { |
|
if (!(bio->bi_opf & (REQ_META|REQ_PRIO)) && |
|
(dc->cache_readahead_policy != BCH_CACHE_READA_ALL)) |
|
goto skip; |
|
} |
|
|
|
if (bio->bi_iter.bi_sector & (c->cache->sb.block_size - 1) || |
|
bio_sectors(bio) & (c->cache->sb.block_size - 1)) { |
|
pr_debug("skipping unaligned io\n"); |
|
goto skip; |
|
} |
|
|
|
if (bypass_torture_test(dc)) { |
|
if ((get_random_int() & 3) == 3) |
|
goto skip; |
|
else |
|
goto rescale; |
|
} |
|
|
|
congested = bch_get_congested(c); |
|
if (!congested && !dc->sequential_cutoff) |
|
goto rescale; |
|
|
|
spin_lock(&dc->io_lock); |
|
|
|
hlist_for_each_entry(i, iohash(dc, bio->bi_iter.bi_sector), hash) |
|
if (i->last == bio->bi_iter.bi_sector && |
|
time_before(jiffies, i->jiffies)) |
|
goto found; |
|
|
|
i = list_first_entry(&dc->io_lru, struct io, lru); |
|
|
|
add_sequential(task); |
|
i->sequential = 0; |
|
found: |
|
if (i->sequential + bio->bi_iter.bi_size > i->sequential) |
|
i->sequential += bio->bi_iter.bi_size; |
|
|
|
i->last = bio_end_sector(bio); |
|
i->jiffies = jiffies + msecs_to_jiffies(5000); |
|
task->sequential_io = i->sequential; |
|
|
|
hlist_del(&i->hash); |
|
hlist_add_head(&i->hash, iohash(dc, i->last)); |
|
list_move_tail(&i->lru, &dc->io_lru); |
|
|
|
spin_unlock(&dc->io_lock); |
|
|
|
sectors = max(task->sequential_io, |
|
task->sequential_io_avg) >> 9; |
|
|
|
if (dc->sequential_cutoff && |
|
sectors >= dc->sequential_cutoff >> 9) { |
|
trace_bcache_bypass_sequential(bio); |
|
goto skip; |
|
} |
|
|
|
if (congested && sectors >= congested) { |
|
trace_bcache_bypass_congested(bio); |
|
goto skip; |
|
} |
|
|
|
rescale: |
|
bch_rescale_priorities(c, bio_sectors(bio)); |
|
return false; |
|
skip: |
|
bch_mark_sectors_bypassed(c, dc, bio_sectors(bio)); |
|
return true; |
|
} |
|
|
|
/* Cache lookup */ |
|
|
|
struct search { |
|
/* Stack frame for bio_complete */ |
|
struct closure cl; |
|
|
|
struct bbio bio; |
|
struct bio *orig_bio; |
|
struct bio *cache_miss; |
|
struct bcache_device *d; |
|
|
|
unsigned int insert_bio_sectors; |
|
unsigned int recoverable:1; |
|
unsigned int write:1; |
|
unsigned int read_dirty_data:1; |
|
unsigned int cache_missed:1; |
|
|
|
struct block_device *orig_bdev; |
|
unsigned long start_time; |
|
|
|
struct btree_op op; |
|
struct data_insert_op iop; |
|
}; |
|
|
|
static void bch_cache_read_endio(struct bio *bio) |
|
{ |
|
struct bbio *b = container_of(bio, struct bbio, bio); |
|
struct closure *cl = bio->bi_private; |
|
struct search *s = container_of(cl, struct search, cl); |
|
|
|
/* |
|
* If the bucket was reused while our bio was in flight, we might have |
|
* read the wrong data. Set s->error but not error so it doesn't get |
|
* counted against the cache device, but we'll still reread the data |
|
* from the backing device. |
|
*/ |
|
|
|
if (bio->bi_status) |
|
s->iop.status = bio->bi_status; |
|
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.status = BLK_STS_IOERR; |
|
} |
|
|
|
bch_bbio_endio(s->iop.c, bio, bio->bi_status, "reading from cache"); |
|
} |
|
|
|
/* |
|
* Read from a single key, handling the initial cache miss if the key starts in |
|
* the middle of the bio |
|
*/ |
|
static int cache_lookup_fn(struct btree_op *op, struct btree *b, struct bkey *k) |
|
{ |
|
struct search *s = container_of(op, struct search, op); |
|
struct bio *n, *bio = &s->bio.bio; |
|
struct bkey *bio_key; |
|
unsigned int ptr; |
|
|
|
if (bkey_cmp(k, &KEY(s->iop.inode, bio->bi_iter.bi_sector, 0)) <= 0) |
|
return MAP_CONTINUE; |
|
|
|
if (KEY_INODE(k) != s->iop.inode || |
|
KEY_START(k) > bio->bi_iter.bi_sector) { |
|
unsigned int bio_sectors = bio_sectors(bio); |
|
unsigned int sectors = KEY_INODE(k) == s->iop.inode |
|
? min_t(uint64_t, INT_MAX, |
|
KEY_START(k) - bio->bi_iter.bi_sector) |
|
: INT_MAX; |
|
int ret = s->d->cache_miss(b, s, bio, sectors); |
|
|
|
if (ret != MAP_CONTINUE) |
|
return ret; |
|
|
|
/* if this was a complete miss we shouldn't get here */ |
|
BUG_ON(bio_sectors <= sectors); |
|
} |
|
|
|
if (!KEY_SIZE(k)) |
|
return MAP_CONTINUE; |
|
|
|
/* XXX: figure out best pointer - for multiple cache devices */ |
|
ptr = 0; |
|
|
|
PTR_BUCKET(b->c, k, ptr)->prio = INITIAL_PRIO; |
|
|
|
if (KEY_DIRTY(k)) |
|
s->read_dirty_data = true; |
|
|
|
n = bio_next_split(bio, min_t(uint64_t, INT_MAX, |
|
KEY_OFFSET(k) - bio->bi_iter.bi_sector), |
|
GFP_NOIO, &s->d->bio_split); |
|
|
|
bio_key = &container_of(n, struct bbio, bio)->key; |
|
bch_bkey_copy_single_ptr(bio_key, k, ptr); |
|
|
|
bch_cut_front(&KEY(s->iop.inode, n->bi_iter.bi_sector, 0), bio_key); |
|
bch_cut_back(&KEY(s->iop.inode, bio_end_sector(n), 0), bio_key); |
|
|
|
n->bi_end_io = bch_cache_read_endio; |
|
n->bi_private = &s->cl; |
|
|
|
/* |
|
* The bucket we're reading from might be reused while our bio |
|
* is in flight, and we could then end up reading the wrong |
|
* data. |
|
* |
|
* We guard against this by checking (in cache_read_endio()) if |
|
* the pointer is stale again; if so, we treat it as an error |
|
* and reread from the backing device (but we don't pass that |
|
* error up anywhere). |
|
*/ |
|
|
|
__bch_submit_bbio(n, b->c); |
|
return n == bio ? MAP_DONE : MAP_CONTINUE; |
|
} |
|
|
|
static void cache_lookup(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, iop.cl); |
|
struct bio *bio = &s->bio.bio; |
|
struct cached_dev *dc; |
|
int ret; |
|
|
|
bch_btree_op_init(&s->op, -1); |
|
|
|
ret = bch_btree_map_keys(&s->op, s->iop.c, |
|
&KEY(s->iop.inode, bio->bi_iter.bi_sector, 0), |
|
cache_lookup_fn, MAP_END_KEY); |
|
if (ret == -EAGAIN) { |
|
continue_at(cl, cache_lookup, bcache_wq); |
|
return; |
|
} |
|
|
|
/* |
|
* We might meet err when searching the btree, If that happens, we will |
|
* get negative ret, in this scenario we should not recover data from |
|
* backing device (when cache device is dirty) because we don't know |
|
* whether bkeys the read request covered are all clean. |
|
* |
|
* And after that happened, s->iop.status is still its initial value |
|
* before we submit s->bio.bio |
|
*/ |
|
if (ret < 0) { |
|
BUG_ON(ret == -EINTR); |
|
if (s->d && s->d->c && |
|
!UUID_FLASH_ONLY(&s->d->c->uuids[s->d->id])) { |
|
dc = container_of(s->d, struct cached_dev, disk); |
|
if (dc && atomic_read(&dc->has_dirty)) |
|
s->recoverable = false; |
|
} |
|
if (!s->iop.status) |
|
s->iop.status = BLK_STS_IOERR; |
|
} |
|
|
|
closure_return(cl); |
|
} |
|
|
|
/* Common code for the make_request functions */ |
|
|
|
static void request_endio(struct bio *bio) |
|
{ |
|
struct closure *cl = bio->bi_private; |
|
|
|
if (bio->bi_status) { |
|
struct search *s = container_of(cl, struct search, cl); |
|
|
|
s->iop.status = bio->bi_status; |
|
/* Only cache read errors are recoverable */ |
|
s->recoverable = false; |
|
} |
|
|
|
bio_put(bio); |
|
closure_put(cl); |
|
} |
|
|
|
static void backing_request_endio(struct bio *bio) |
|
{ |
|
struct closure *cl = bio->bi_private; |
|
|
|
if (bio->bi_status) { |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct cached_dev *dc = container_of(s->d, |
|
struct cached_dev, disk); |
|
/* |
|
* If a bio has REQ_PREFLUSH for writeback mode, it is |
|
* speically assembled in cached_dev_write() for a non-zero |
|
* write request which has REQ_PREFLUSH. we don't set |
|
* s->iop.status by this failure, the status will be decided |
|
* by result of bch_data_insert() operation. |
|
*/ |
|
if (unlikely(s->iop.writeback && |
|
bio->bi_opf & REQ_PREFLUSH)) { |
|
pr_err("Can't flush %s: returned bi_status %i\n", |
|
dc->backing_dev_name, bio->bi_status); |
|
} else { |
|
/* set to orig_bio->bi_status in bio_complete() */ |
|
s->iop.status = bio->bi_status; |
|
} |
|
s->recoverable = false; |
|
/* should count I/O error for backing device here */ |
|
bch_count_backing_io_errors(dc, bio); |
|
} |
|
|
|
bio_put(bio); |
|
closure_put(cl); |
|
} |
|
|
|
static void bio_complete(struct search *s) |
|
{ |
|
if (s->orig_bio) { |
|
/* Count on bcache device */ |
|
bio_end_io_acct_remapped(s->orig_bio, s->start_time, |
|
s->orig_bdev); |
|
trace_bcache_request_end(s->d, s->orig_bio); |
|
s->orig_bio->bi_status = s->iop.status; |
|
bio_endio(s->orig_bio); |
|
s->orig_bio = NULL; |
|
} |
|
} |
|
|
|
static void do_bio_hook(struct search *s, |
|
struct bio *orig_bio, |
|
bio_end_io_t *end_io_fn) |
|
{ |
|
struct bio *bio = &s->bio.bio; |
|
|
|
bio_init(bio, NULL, 0); |
|
__bio_clone_fast(bio, orig_bio); |
|
/* |
|
* bi_end_io can be set separately somewhere else, e.g. the |
|
* variants in, |
|
* - cache_bio->bi_end_io from cached_dev_cache_miss() |
|
* - n->bi_end_io from cache_lookup_fn() |
|
*/ |
|
bio->bi_end_io = end_io_fn; |
|
bio->bi_private = &s->cl; |
|
|
|
bio_cnt_set(bio, 3); |
|
} |
|
|
|
static void search_free(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
|
|
atomic_dec(&s->iop.c->search_inflight); |
|
|
|
if (s->iop.bio) |
|
bio_put(s->iop.bio); |
|
|
|
bio_complete(s); |
|
closure_debug_destroy(cl); |
|
mempool_free(s, &s->iop.c->search); |
|
} |
|
|
|
static inline struct search *search_alloc(struct bio *bio, |
|
struct bcache_device *d, struct block_device *orig_bdev, |
|
unsigned long start_time) |
|
{ |
|
struct search *s; |
|
|
|
s = mempool_alloc(&d->c->search, GFP_NOIO); |
|
|
|
closure_init(&s->cl, NULL); |
|
do_bio_hook(s, bio, request_endio); |
|
atomic_inc(&d->c->search_inflight); |
|
|
|
s->orig_bio = bio; |
|
s->cache_miss = NULL; |
|
s->cache_missed = 0; |
|
s->d = d; |
|
s->recoverable = 1; |
|
s->write = op_is_write(bio_op(bio)); |
|
s->read_dirty_data = 0; |
|
/* Count on the bcache device */ |
|
s->orig_bdev = orig_bdev; |
|
s->start_time = start_time; |
|
s->iop.c = d->c; |
|
s->iop.bio = NULL; |
|
s->iop.inode = d->id; |
|
s->iop.write_point = hash_long((unsigned long) current, 16); |
|
s->iop.write_prio = 0; |
|
s->iop.status = 0; |
|
s->iop.flags = 0; |
|
s->iop.flush_journal = op_is_flush(bio->bi_opf); |
|
s->iop.wq = bcache_wq; |
|
|
|
return s; |
|
} |
|
|
|
/* Cached devices */ |
|
|
|
static void cached_dev_bio_complete(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); |
|
|
|
cached_dev_put(dc); |
|
search_free(cl); |
|
} |
|
|
|
/* Process reads */ |
|
|
|
static void cached_dev_read_error_done(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
|
|
if (s->iop.replace_collision) |
|
bch_mark_cache_miss_collision(s->iop.c, s->d); |
|
|
|
if (s->iop.bio) |
|
bio_free_pages(s->iop.bio); |
|
|
|
cached_dev_bio_complete(cl); |
|
} |
|
|
|
static void cached_dev_read_error(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct bio *bio = &s->bio.bio; |
|
|
|
/* |
|
* If read request hit dirty data (s->read_dirty_data is true), |
|
* then recovery a failed read request from cached device may |
|
* get a stale data back. So read failure recovery is only |
|
* permitted when read request hit clean data in cache device, |
|
* or when cache read race happened. |
|
*/ |
|
if (s->recoverable && !s->read_dirty_data) { |
|
/* Retry from the backing device: */ |
|
trace_bcache_read_retry(s->orig_bio); |
|
|
|
s->iop.status = 0; |
|
do_bio_hook(s, s->orig_bio, backing_request_endio); |
|
|
|
/* XXX: invalidate cache */ |
|
|
|
/* I/O request sent to backing device */ |
|
closure_bio_submit(s->iop.c, bio, cl); |
|
} |
|
|
|
continue_at(cl, cached_dev_read_error_done, NULL); |
|
} |
|
|
|
static void cached_dev_cache_miss_done(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct bcache_device *d = s->d; |
|
|
|
if (s->iop.replace_collision) |
|
bch_mark_cache_miss_collision(s->iop.c, s->d); |
|
|
|
if (s->iop.bio) |
|
bio_free_pages(s->iop.bio); |
|
|
|
cached_dev_bio_complete(cl); |
|
closure_put(&d->cl); |
|
} |
|
|
|
static void cached_dev_read_done(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); |
|
|
|
/* |
|
* We had a cache miss; cache_bio now contains data ready to be inserted |
|
* into the cache. |
|
* |
|
* First, we copy the data we just read from cache_bio's bounce buffers |
|
* to the buffers the original bio pointed to: |
|
*/ |
|
|
|
if (s->iop.bio) { |
|
bio_reset(s->iop.bio); |
|
s->iop.bio->bi_iter.bi_sector = |
|
s->cache_miss->bi_iter.bi_sector; |
|
bio_copy_dev(s->iop.bio, s->cache_miss); |
|
s->iop.bio->bi_iter.bi_size = s->insert_bio_sectors << 9; |
|
bch_bio_map(s->iop.bio, NULL); |
|
|
|
bio_copy_data(s->cache_miss, s->iop.bio); |
|
|
|
bio_put(s->cache_miss); |
|
s->cache_miss = NULL; |
|
} |
|
|
|
if (verify(dc) && s->recoverable && !s->read_dirty_data) |
|
bch_data_verify(dc, s->orig_bio); |
|
|
|
closure_get(&dc->disk.cl); |
|
bio_complete(s); |
|
|
|
if (s->iop.bio && |
|
!test_bit(CACHE_SET_STOPPING, &s->iop.c->flags)) { |
|
BUG_ON(!s->iop.replace); |
|
closure_call(&s->iop.cl, bch_data_insert, NULL, cl); |
|
} |
|
|
|
continue_at(cl, cached_dev_cache_miss_done, NULL); |
|
} |
|
|
|
static void cached_dev_read_done_bh(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); |
|
|
|
bch_mark_cache_accounting(s->iop.c, s->d, |
|
!s->cache_missed, s->iop.bypass); |
|
trace_bcache_read(s->orig_bio, !s->cache_missed, s->iop.bypass); |
|
|
|
if (s->iop.status) |
|
continue_at_nobarrier(cl, cached_dev_read_error, bcache_wq); |
|
else if (s->iop.bio || verify(dc)) |
|
continue_at_nobarrier(cl, cached_dev_read_done, bcache_wq); |
|
else |
|
continue_at_nobarrier(cl, cached_dev_bio_complete, NULL); |
|
} |
|
|
|
static int cached_dev_cache_miss(struct btree *b, struct search *s, |
|
struct bio *bio, unsigned int sectors) |
|
{ |
|
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; |
|
|
|
if (s->cache_miss || s->iop.bypass) { |
|
miss = bio_next_split(bio, sectors, GFP_NOIO, &s->d->bio_split); |
|
ret = miss == bio ? MAP_DONE : MAP_CONTINUE; |
|
goto out_submit; |
|
} |
|
|
|
/* Limitation for valid replace key size and cache_bio bvecs number */ |
|
size_limit = min_t(unsigned int, BIO_MAX_VECS * 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, |
|
s->insert_bio_sectors); |
|
|
|
ret = bch_btree_insert_check_key(b, &s->op, &s->iop.replace_key); |
|
if (ret) |
|
return ret; |
|
|
|
s->iop.replace = true; |
|
|
|
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; |
|
|
|
cache_bio = bio_alloc_bioset(GFP_NOWAIT, |
|
DIV_ROUND_UP(s->insert_bio_sectors, PAGE_SECTORS), |
|
&dc->disk.bio_split); |
|
if (!cache_bio) |
|
goto out_submit; |
|
|
|
cache_bio->bi_iter.bi_sector = miss->bi_iter.bi_sector; |
|
bio_copy_dev(cache_bio, miss); |
|
cache_bio->bi_iter.bi_size = s->insert_bio_sectors << 9; |
|
|
|
cache_bio->bi_end_io = backing_request_endio; |
|
cache_bio->bi_private = &s->cl; |
|
|
|
bch_bio_map(cache_bio, NULL); |
|
if (bch_bio_alloc_pages(cache_bio, __GFP_NOWARN|GFP_NOIO)) |
|
goto out_put; |
|
|
|
s->cache_miss = miss; |
|
s->iop.bio = cache_bio; |
|
bio_get(cache_bio); |
|
/* I/O request sent to backing device */ |
|
closure_bio_submit(s->iop.c, cache_bio, &s->cl); |
|
|
|
return ret; |
|
out_put: |
|
bio_put(cache_bio); |
|
out_submit: |
|
miss->bi_end_io = backing_request_endio; |
|
miss->bi_private = &s->cl; |
|
/* I/O request sent to backing device */ |
|
closure_bio_submit(s->iop.c, miss, &s->cl); |
|
return ret; |
|
} |
|
|
|
static void cached_dev_read(struct cached_dev *dc, struct search *s) |
|
{ |
|
struct closure *cl = &s->cl; |
|
|
|
closure_call(&s->iop.cl, cache_lookup, NULL, cl); |
|
continue_at(cl, cached_dev_read_done_bh, NULL); |
|
} |
|
|
|
/* Process writes */ |
|
|
|
static void cached_dev_write_complete(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct cached_dev *dc = container_of(s->d, struct cached_dev, disk); |
|
|
|
up_read_non_owner(&dc->writeback_lock); |
|
cached_dev_bio_complete(cl); |
|
} |
|
|
|
static void cached_dev_write(struct cached_dev *dc, struct search *s) |
|
{ |
|
struct closure *cl = &s->cl; |
|
struct bio *bio = &s->bio.bio; |
|
struct bkey start = KEY(dc->disk.id, bio->bi_iter.bi_sector, 0); |
|
struct bkey end = KEY(dc->disk.id, bio_end_sector(bio), 0); |
|
|
|
bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys, &start, &end); |
|
|
|
down_read_non_owner(&dc->writeback_lock); |
|
if (bch_keybuf_check_overlapping(&dc->writeback_keys, &start, &end)) { |
|
/* |
|
* We overlap with some dirty data undergoing background |
|
* writeback, force this write to writeback |
|
*/ |
|
s->iop.bypass = false; |
|
s->iop.writeback = true; |
|
} |
|
|
|
/* |
|
* Discards aren't _required_ to do anything, so skipping if |
|
* check_overlapping returned true is ok |
|
* |
|
* But check_overlapping drops dirty keys for which io hasn't started, |
|
* so we still want to call it. |
|
*/ |
|
if (bio_op(bio) == REQ_OP_DISCARD) |
|
s->iop.bypass = true; |
|
|
|
if (should_writeback(dc, s->orig_bio, |
|
cache_mode(dc), |
|
s->iop.bypass)) { |
|
s->iop.bypass = false; |
|
s->iop.writeback = true; |
|
} |
|
|
|
if (s->iop.bypass) { |
|
s->iop.bio = s->orig_bio; |
|
bio_get(s->iop.bio); |
|
|
|
if (bio_op(bio) == REQ_OP_DISCARD && |
|
!blk_queue_discard(bdev_get_queue(dc->bdev))) |
|
goto insert_data; |
|
|
|
/* I/O request sent to backing device */ |
|
bio->bi_end_io = backing_request_endio; |
|
closure_bio_submit(s->iop.c, bio, cl); |
|
|
|
} else if (s->iop.writeback) { |
|
bch_writeback_add(dc); |
|
s->iop.bio = bio; |
|
|
|
if (bio->bi_opf & REQ_PREFLUSH) { |
|
/* |
|
* Also need to send a flush to the backing |
|
* device. |
|
*/ |
|
struct bio *flush; |
|
|
|
flush = bio_alloc_bioset(GFP_NOIO, 0, |
|
&dc->disk.bio_split); |
|
if (!flush) { |
|
s->iop.status = BLK_STS_RESOURCE; |
|
goto insert_data; |
|
} |
|
bio_copy_dev(flush, bio); |
|
flush->bi_end_io = backing_request_endio; |
|
flush->bi_private = cl; |
|
flush->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; |
|
/* I/O request sent to backing device */ |
|
closure_bio_submit(s->iop.c, flush, cl); |
|
} |
|
} else { |
|
s->iop.bio = bio_clone_fast(bio, GFP_NOIO, &dc->disk.bio_split); |
|
/* I/O request sent to backing device */ |
|
bio->bi_end_io = backing_request_endio; |
|
closure_bio_submit(s->iop.c, bio, cl); |
|
} |
|
|
|
insert_data: |
|
closure_call(&s->iop.cl, bch_data_insert, NULL, cl); |
|
continue_at(cl, cached_dev_write_complete, NULL); |
|
} |
|
|
|
static void cached_dev_nodata(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
struct bio *bio = &s->bio.bio; |
|
|
|
if (s->iop.flush_journal) |
|
bch_journal_meta(s->iop.c, cl); |
|
|
|
/* If it's a flush, we send the flush to the backing device too */ |
|
bio->bi_end_io = backing_request_endio; |
|
closure_bio_submit(s->iop.c, bio, cl); |
|
|
|
continue_at(cl, cached_dev_bio_complete, NULL); |
|
} |
|
|
|
struct detached_dev_io_private { |
|
struct bcache_device *d; |
|
unsigned long start_time; |
|
bio_end_io_t *bi_end_io; |
|
void *bi_private; |
|
struct block_device *orig_bdev; |
|
}; |
|
|
|
static void detached_dev_end_io(struct bio *bio) |
|
{ |
|
struct detached_dev_io_private *ddip; |
|
|
|
ddip = bio->bi_private; |
|
bio->bi_end_io = ddip->bi_end_io; |
|
bio->bi_private = ddip->bi_private; |
|
|
|
/* Count on the bcache device */ |
|
bio_end_io_acct_remapped(bio, ddip->start_time, ddip->orig_bdev); |
|
|
|
if (bio->bi_status) { |
|
struct cached_dev *dc = container_of(ddip->d, |
|
struct cached_dev, disk); |
|
/* should count I/O error for backing device here */ |
|
bch_count_backing_io_errors(dc, bio); |
|
} |
|
|
|
kfree(ddip); |
|
bio->bi_end_io(bio); |
|
} |
|
|
|
static void detached_dev_do_request(struct bcache_device *d, struct bio *bio, |
|
struct block_device *orig_bdev, unsigned long start_time) |
|
{ |
|
struct detached_dev_io_private *ddip; |
|
struct cached_dev *dc = container_of(d, struct cached_dev, disk); |
|
|
|
/* |
|
* no need to call closure_get(&dc->disk.cl), |
|
* because upper layer had already opened bcache device, |
|
* which would call closure_get(&dc->disk.cl) |
|
*/ |
|
ddip = kzalloc(sizeof(struct detached_dev_io_private), GFP_NOIO); |
|
ddip->d = d; |
|
/* Count on the bcache device */ |
|
ddip->orig_bdev = orig_bdev; |
|
ddip->start_time = start_time; |
|
ddip->bi_end_io = bio->bi_end_io; |
|
ddip->bi_private = bio->bi_private; |
|
bio->bi_end_io = detached_dev_end_io; |
|
bio->bi_private = ddip; |
|
|
|
if ((bio_op(bio) == REQ_OP_DISCARD) && |
|
!blk_queue_discard(bdev_get_queue(dc->bdev))) |
|
bio->bi_end_io(bio); |
|
else |
|
submit_bio_noacct(bio); |
|
} |
|
|
|
static void quit_max_writeback_rate(struct cache_set *c, |
|
struct cached_dev *this_dc) |
|
{ |
|
int i; |
|
struct bcache_device *d; |
|
struct cached_dev *dc; |
|
|
|
/* |
|
* mutex bch_register_lock may compete with other parallel requesters, |
|
* or attach/detach operations on other backing device. Waiting to |
|
* the mutex lock may increase I/O request latency for seconds or more. |
|
* To avoid such situation, if mutext_trylock() failed, only writeback |
|
* rate of current cached device is set to 1, and __update_write_back() |
|
* will decide writeback rate of other cached devices (remember now |
|
* c->idle_counter is 0 already). |
|
*/ |
|
if (mutex_trylock(&bch_register_lock)) { |
|
for (i = 0; i < c->devices_max_used; i++) { |
|
if (!c->devices[i]) |
|
continue; |
|
|
|
if (UUID_FLASH_ONLY(&c->uuids[i])) |
|
continue; |
|
|
|
d = c->devices[i]; |
|
dc = container_of(d, struct cached_dev, disk); |
|
/* |
|
* set writeback rate to default minimum value, |
|
* then let update_writeback_rate() to decide the |
|
* upcoming rate. |
|
*/ |
|
atomic_long_set(&dc->writeback_rate.rate, 1); |
|
} |
|
mutex_unlock(&bch_register_lock); |
|
} else |
|
atomic_long_set(&this_dc->writeback_rate.rate, 1); |
|
} |
|
|
|
/* Cached devices - read & write stuff */ |
|
|
|
blk_qc_t cached_dev_submit_bio(struct bio *bio) |
|
{ |
|
struct search *s; |
|
struct block_device *orig_bdev = bio->bi_bdev; |
|
struct bcache_device *d = orig_bdev->bd_disk->private_data; |
|
struct cached_dev *dc = container_of(d, struct cached_dev, disk); |
|
unsigned long start_time; |
|
int rw = bio_data_dir(bio); |
|
|
|
if (unlikely((d->c && test_bit(CACHE_SET_IO_DISABLE, &d->c->flags)) || |
|
dc->io_disable)) { |
|
bio->bi_status = BLK_STS_IOERR; |
|
bio_endio(bio); |
|
return BLK_QC_T_NONE; |
|
} |
|
|
|
if (likely(d->c)) { |
|
if (atomic_read(&d->c->idle_counter)) |
|
atomic_set(&d->c->idle_counter, 0); |
|
/* |
|
* If at_max_writeback_rate of cache set is true and new I/O |
|
* comes, quit max writeback rate of all cached devices |
|
* attached to this cache set, and set at_max_writeback_rate |
|
* to false. |
|
*/ |
|
if (unlikely(atomic_read(&d->c->at_max_writeback_rate) == 1)) { |
|
atomic_set(&d->c->at_max_writeback_rate, 0); |
|
quit_max_writeback_rate(d->c, dc); |
|
} |
|
} |
|
|
|
start_time = bio_start_io_acct(bio); |
|
|
|
bio_set_dev(bio, dc->bdev); |
|
bio->bi_iter.bi_sector += dc->sb.data_offset; |
|
|
|
if (cached_dev_get(dc)) { |
|
s = search_alloc(bio, d, orig_bdev, start_time); |
|
trace_bcache_request_start(s->d, bio); |
|
|
|
if (!bio->bi_iter.bi_size) { |
|
/* |
|
* can't call bch_journal_meta from under |
|
* submit_bio_noacct |
|
*/ |
|
continue_at_nobarrier(&s->cl, |
|
cached_dev_nodata, |
|
bcache_wq); |
|
} else { |
|
s->iop.bypass = check_should_bypass(dc, bio); |
|
|
|
if (rw) |
|
cached_dev_write(dc, s); |
|
else |
|
cached_dev_read(dc, s); |
|
} |
|
} else |
|
/* I/O request sent to backing device */ |
|
detached_dev_do_request(d, bio, orig_bdev, start_time); |
|
|
|
return BLK_QC_T_NONE; |
|
} |
|
|
|
static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
struct cached_dev *dc = container_of(d, struct cached_dev, disk); |
|
|
|
if (dc->io_disable) |
|
return -EIO; |
|
if (!dc->bdev->bd_disk->fops->ioctl) |
|
return -ENOTTY; |
|
return dc->bdev->bd_disk->fops->ioctl(dc->bdev, mode, cmd, arg); |
|
} |
|
|
|
void bch_cached_dev_request_init(struct cached_dev *dc) |
|
{ |
|
dc->disk.cache_miss = cached_dev_cache_miss; |
|
dc->disk.ioctl = cached_dev_ioctl; |
|
} |
|
|
|
/* Flash backed devices */ |
|
|
|
static int flash_dev_cache_miss(struct btree *b, struct search *s, |
|
struct bio *bio, unsigned int sectors) |
|
{ |
|
unsigned int bytes = min(sectors, bio_sectors(bio)) << 9; |
|
|
|
swap(bio->bi_iter.bi_size, bytes); |
|
zero_fill_bio(bio); |
|
swap(bio->bi_iter.bi_size, bytes); |
|
|
|
bio_advance(bio, bytes); |
|
|
|
if (!bio->bi_iter.bi_size) |
|
return MAP_DONE; |
|
|
|
return MAP_CONTINUE; |
|
} |
|
|
|
static void flash_dev_nodata(struct closure *cl) |
|
{ |
|
struct search *s = container_of(cl, struct search, cl); |
|
|
|
if (s->iop.flush_journal) |
|
bch_journal_meta(s->iop.c, cl); |
|
|
|
continue_at(cl, search_free, NULL); |
|
} |
|
|
|
blk_qc_t flash_dev_submit_bio(struct bio *bio) |
|
{ |
|
struct search *s; |
|
struct closure *cl; |
|
struct bcache_device *d = bio->bi_bdev->bd_disk->private_data; |
|
|
|
if (unlikely(d->c && test_bit(CACHE_SET_IO_DISABLE, &d->c->flags))) { |
|
bio->bi_status = BLK_STS_IOERR; |
|
bio_endio(bio); |
|
return BLK_QC_T_NONE; |
|
} |
|
|
|
s = search_alloc(bio, d, bio->bi_bdev, bio_start_io_acct(bio)); |
|
cl = &s->cl; |
|
bio = &s->bio.bio; |
|
|
|
trace_bcache_request_start(s->d, bio); |
|
|
|
if (!bio->bi_iter.bi_size) { |
|
/* |
|
* can't call bch_journal_meta from under submit_bio_noacct |
|
*/ |
|
continue_at_nobarrier(&s->cl, |
|
flash_dev_nodata, |
|
bcache_wq); |
|
return BLK_QC_T_NONE; |
|
} else if (bio_data_dir(bio)) { |
|
bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys, |
|
&KEY(d->id, bio->bi_iter.bi_sector, 0), |
|
&KEY(d->id, bio_end_sector(bio), 0)); |
|
|
|
s->iop.bypass = (bio_op(bio) == REQ_OP_DISCARD) != 0; |
|
s->iop.writeback = true; |
|
s->iop.bio = bio; |
|
|
|
closure_call(&s->iop.cl, bch_data_insert, NULL, cl); |
|
} else { |
|
closure_call(&s->iop.cl, cache_lookup, NULL, cl); |
|
} |
|
|
|
continue_at(cl, search_free, NULL); |
|
return BLK_QC_T_NONE; |
|
} |
|
|
|
static int flash_dev_ioctl(struct bcache_device *d, fmode_t mode, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
return -ENOTTY; |
|
} |
|
|
|
void bch_flash_dev_request_init(struct bcache_device *d) |
|
{ |
|
d->cache_miss = flash_dev_cache_miss; |
|
d->ioctl = flash_dev_ioctl; |
|
} |
|
|
|
void bch_request_exit(void) |
|
{ |
|
kmem_cache_destroy(bch_search_cache); |
|
} |
|
|
|
int __init bch_request_init(void) |
|
{ |
|
bch_search_cache = KMEM_CACHE(search, 0); |
|
if (!bch_search_cache) |
|
return -ENOMEM; |
|
|
|
return 0; |
|
}
|
|
|