diff options
| -rw-r--r-- | drivers/md/dm-kcopyd.c | 31 | ||||
| -rw-r--r-- | drivers/md/dm-snap.c | 60 | ||||
| -rw-r--r-- | include/linux/dm-kcopyd.h | 15 |
3 files changed, 103 insertions, 3 deletions
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c index 98725e11932..f8214702963 100644 --- a/drivers/md/dm-kcopyd.c +++ b/drivers/md/dm-kcopyd.c @@ -617,6 +617,37 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from, } EXPORT_SYMBOL(dm_kcopyd_copy); +void *dm_kcopyd_prepare_callback(struct dm_kcopyd_client *kc, + dm_kcopyd_notify_fn fn, void *context) +{ + struct kcopyd_job *job; + + job = mempool_alloc(kc->job_pool, GFP_NOIO); + + memset(job, 0, sizeof(struct kcopyd_job)); + job->kc = kc; + job->fn = fn; + job->context = context; + + atomic_inc(&kc->nr_jobs); + + return job; +} +EXPORT_SYMBOL(dm_kcopyd_prepare_callback); + +void dm_kcopyd_do_callback(void *j, int read_err, unsigned long write_err) +{ + struct kcopyd_job *job = j; + struct dm_kcopyd_client *kc = job->kc; + + job->read_err = read_err; + job->write_err = write_err; + + push(&kc->complete_jobs, job); + wake(kc); +} +EXPORT_SYMBOL(dm_kcopyd_do_callback); + /* * Cancels a kcopyd job, eg. someone might be deactivating a * mirror. diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 94dee05dd28..6f758870fc1 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -170,6 +170,13 @@ struct dm_snap_pending_exception { * kcopyd. */ int started; + + /* + * For writing a complete chunk, bypassing the copy. + */ + struct bio *full_bio; + bio_end_io_t *full_bio_end_io; + void *full_bio_private; }; /* @@ -1369,6 +1376,7 @@ static void pending_complete(struct dm_snap_pending_exception *pe, int success) struct dm_snapshot *s = pe->snap; struct bio *origin_bios = NULL; struct bio *snapshot_bios = NULL; + struct bio *full_bio = NULL; int error = 0; if (!success) { @@ -1408,6 +1416,11 @@ out: dm_remove_exception(&pe->e); snapshot_bios = bio_list_get(&pe->snapshot_bios); origin_bios = bio_list_get(&pe->origin_bios); + full_bio = pe->full_bio; + if (full_bio) { + full_bio->bi_end_io = pe->full_bio_end_io; + full_bio->bi_private = pe->full_bio_private; + } free_pending_exception(pe); increment_pending_exceptions_done_count(); @@ -1415,10 +1428,15 @@ out: up_write(&s->lock); /* Submit any pending write bios */ - if (error) + if (error) { + if (full_bio) + bio_io_error(full_bio); error_bios(snapshot_bios); - else + } else { + if (full_bio) + bio_endio(full_bio, 0); flush_bios(snapshot_bios); + } retry_origin_bios(s, origin_bios); } @@ -1472,6 +1490,32 @@ static void start_copy(struct dm_snap_pending_exception *pe) dm_kcopyd_copy(s->kcopyd_client, &src, 1, &dest, 0, copy_callback, pe); } +static void full_bio_end_io(struct bio *bio, int error) +{ + void *callback_data = bio->bi_private; + + dm_kcopyd_do_callback(callback_data, 0, error ? 1 : 0); +} + +static void start_full_bio(struct dm_snap_pending_exception *pe, + struct bio *bio) +{ + struct dm_snapshot *s = pe->snap; + void *callback_data; + + pe->full_bio = bio; + pe->full_bio_end_io = bio->bi_end_io; + pe->full_bio_private = bio->bi_private; + + callback_data = dm_kcopyd_prepare_callback(s->kcopyd_client, + copy_callback, pe); + + bio->bi_end_io = full_bio_end_io; + bio->bi_private = callback_data; + + generic_make_request(bio); +} + static struct dm_snap_pending_exception * __lookup_pending_exception(struct dm_snapshot *s, chunk_t chunk) { @@ -1507,6 +1551,7 @@ __find_pending_exception(struct dm_snapshot *s, bio_list_init(&pe->origin_bios); bio_list_init(&pe->snapshot_bios); pe->started = 0; + pe->full_bio = NULL; if (s->store->type->prepare_exception(s->store, &pe->e)) { free_pending_exception(pe); @@ -1600,10 +1645,19 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio, } remap_exception(s, &pe->e, bio, chunk); - bio_list_add(&pe->snapshot_bios, bio); r = DM_MAPIO_SUBMITTED; + if (!pe->started && + bio->bi_size == (s->store->chunk_size << SECTOR_SHIFT)) { + pe->started = 1; + up_write(&s->lock); + start_full_bio(pe, bio); + goto out; + } + + bio_list_add(&pe->snapshot_bios, bio); + if (!pe->started) { /* this is protected by snap->lock */ pe->started = 1; diff --git a/include/linux/dm-kcopyd.h b/include/linux/dm-kcopyd.h index 298d587e349..5e54458e920 100644 --- a/include/linux/dm-kcopyd.h +++ b/include/linux/dm-kcopyd.h @@ -42,5 +42,20 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from, unsigned num_dests, struct dm_io_region *dests, unsigned flags, dm_kcopyd_notify_fn fn, void *context); +/* + * Prepare a callback and submit it via the kcopyd thread. + * + * dm_kcopyd_prepare_callback allocates a callback structure and returns it. + * It must not be called from interrupt context. + * The returned value should be passed into dm_kcopyd_do_callback. + * + * dm_kcopyd_do_callback submits the callback. + * It may be called from interrupt context. + * The callback is issued from the kcopyd thread. + */ +void *dm_kcopyd_prepare_callback(struct dm_kcopyd_client *kc, + dm_kcopyd_notify_fn fn, void *context); +void dm_kcopyd_do_callback(void *job, int read_err, unsigned long write_err); + #endif /* __KERNEL__ */ #endif /* _LINUX_DM_KCOPYD_H */ |