dm: support REQ_OP_WRITE_ZEROES

Copy & paste from the REQ_OP_WRITE_SAME code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Christoph Hellwig 2017-04-05 19:21:05 +02:00 committed by Jens Axboe
parent 0f5d690f7b
commit ac62d6208a
9 changed files with 83 additions and 8 deletions

View File

@ -132,6 +132,7 @@ void dm_init_md_queue(struct mapped_device *md);
void dm_init_normal_md_queue(struct mapped_device *md);
int md_in_flight(struct mapped_device *md);
void disable_write_same(struct mapped_device *md);
void disable_write_zeroes(struct mapped_device *md);
static inline struct completion *dm_get_completion_from_kobject(struct kobject *kobj)
{

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@ -312,9 +312,12 @@ static void do_region(int op, int op_flags, unsigned region,
*/
if (op == REQ_OP_DISCARD)
special_cmd_max_sectors = q->limits.max_discard_sectors;
else if (op == REQ_OP_WRITE_ZEROES)
special_cmd_max_sectors = q->limits.max_write_zeroes_sectors;
else if (op == REQ_OP_WRITE_SAME)
special_cmd_max_sectors = q->limits.max_write_same_sectors;
if ((op == REQ_OP_DISCARD || op == REQ_OP_WRITE_SAME) &&
if ((op == REQ_OP_DISCARD || op == REQ_OP_WRITE_ZEROES ||
op == REQ_OP_WRITE_SAME) &&
special_cmd_max_sectors == 0) {
dec_count(io, region, -EOPNOTSUPP);
return;
@ -330,6 +333,7 @@ static void do_region(int op, int op_flags, unsigned region,
*/
switch (op) {
case REQ_OP_DISCARD:
case REQ_OP_WRITE_ZEROES:
num_bvecs = 0;
break;
case REQ_OP_WRITE_SAME:
@ -347,7 +351,7 @@ static void do_region(int op, int op_flags, unsigned region,
bio_set_op_attrs(bio, op, op_flags);
store_io_and_region_in_bio(bio, io, region);
if (op == REQ_OP_DISCARD) {
if (op == REQ_OP_DISCARD || op == REQ_OP_WRITE_ZEROES) {
num_sectors = min_t(sector_t, special_cmd_max_sectors, remaining);
bio->bi_iter.bi_size = num_sectors << SECTOR_SHIFT;
remaining -= num_sectors;

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@ -59,6 +59,7 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv)
ti->num_flush_bios = 1;
ti->num_discard_bios = 1;
ti->num_write_same_bios = 1;
ti->num_write_zeroes_bios = 1;
ti->private = lc;
return 0;

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@ -1103,6 +1103,7 @@ static int multipath_ctr(struct dm_target *ti, unsigned argc, char **argv)
ti->num_flush_bios = 1;
ti->num_discard_bios = 1;
ti->num_write_same_bios = 1;
ti->num_write_zeroes_bios = 1;
if (m->queue_mode == DM_TYPE_BIO_BASED)
ti->per_io_data_size = multipath_per_bio_data_size();
else

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@ -298,9 +298,14 @@ static void dm_done(struct request *clone, int error, bool mapped)
r = rq_end_io(tio->ti, clone, error, &tio->info);
}
if (unlikely(r == -EREMOTEIO && (req_op(clone) == REQ_OP_WRITE_SAME) &&
!clone->q->limits.max_write_same_sectors))
disable_write_same(tio->md);
if (unlikely(r == -EREMOTEIO)) {
if (req_op(clone) == REQ_OP_WRITE_SAME &&
!clone->q->limits.max_write_same_sectors)
disable_write_same(tio->md);
if (req_op(clone) == REQ_OP_WRITE_ZEROES &&
!clone->q->limits.max_write_zeroes_sectors)
disable_write_zeroes(tio->md);
}
if (r <= 0)
/* The target wants to complete the I/O */

View File

@ -169,6 +169,7 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
ti->num_flush_bios = stripes;
ti->num_discard_bios = stripes;
ti->num_write_same_bios = stripes;
ti->num_write_zeroes_bios = stripes;
sc->chunk_size = chunk_size;
if (chunk_size & (chunk_size - 1))
@ -293,6 +294,7 @@ static int stripe_map(struct dm_target *ti, struct bio *bio)
return DM_MAPIO_REMAPPED;
}
if (unlikely(bio_op(bio) == REQ_OP_DISCARD) ||
unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES) ||
unlikely(bio_op(bio) == REQ_OP_WRITE_SAME)) {
target_bio_nr = dm_bio_get_target_bio_nr(bio);
BUG_ON(target_bio_nr >= sc->stripes);

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@ -1533,6 +1533,34 @@ static bool dm_table_supports_write_same(struct dm_table *t)
return true;
}
static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev,
sector_t start, sector_t len, void *data)
{
struct request_queue *q = bdev_get_queue(dev->bdev);
return q && !q->limits.max_write_zeroes_sectors;
}
static bool dm_table_supports_write_zeroes(struct dm_table *t)
{
struct dm_target *ti;
unsigned i = 0;
while (i < dm_table_get_num_targets(t)) {
ti = dm_table_get_target(t, i++);
if (!ti->num_write_zeroes_bios)
return false;
if (!ti->type->iterate_devices ||
ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL))
return false;
}
return true;
}
static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev,
sector_t start, sector_t len, void *data)
{
@ -1603,6 +1631,8 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
if (!dm_table_supports_write_same(t))
q->limits.max_write_same_sectors = 0;
if (!dm_table_supports_write_zeroes(t))
q->limits.max_write_zeroes_sectors = 0;
if (dm_table_all_devices_attribute(t, queue_supports_sg_merge))
queue_flag_clear_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);

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@ -824,6 +824,14 @@ void disable_write_same(struct mapped_device *md)
limits->max_write_same_sectors = 0;
}
void disable_write_zeroes(struct mapped_device *md)
{
struct queue_limits *limits = dm_get_queue_limits(md);
/* device doesn't really support WRITE ZEROES, disable it */
limits->max_write_zeroes_sectors = 0;
}
static void clone_endio(struct bio *bio)
{
int error = bio->bi_error;
@ -850,9 +858,14 @@ static void clone_endio(struct bio *bio)
}
}
if (unlikely(r == -EREMOTEIO && (bio_op(bio) == REQ_OP_WRITE_SAME) &&
!bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors))
disable_write_same(md);
if (unlikely(r == -EREMOTEIO)) {
if (bio_op(bio) == REQ_OP_WRITE_SAME &&
!bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors)
disable_write_same(md);
if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
!bdev_get_queue(bio->bi_bdev)->limits.max_write_zeroes_sectors)
disable_write_zeroes(md);
}
free_tio(tio);
dec_pending(io, error);
@ -1201,6 +1214,11 @@ static unsigned get_num_write_same_bios(struct dm_target *ti)
return ti->num_write_same_bios;
}
static unsigned get_num_write_zeroes_bios(struct dm_target *ti)
{
return ti->num_write_zeroes_bios;
}
typedef bool (*is_split_required_fn)(struct dm_target *ti);
static bool is_split_required_for_discard(struct dm_target *ti)
@ -1255,6 +1273,11 @@ static int __send_write_same(struct clone_info *ci)
return __send_changing_extent_only(ci, get_num_write_same_bios, NULL);
}
static int __send_write_zeroes(struct clone_info *ci)
{
return __send_changing_extent_only(ci, get_num_write_zeroes_bios, NULL);
}
/*
* Select the correct strategy for processing a non-flush bio.
*/
@ -1269,6 +1292,8 @@ static int __split_and_process_non_flush(struct clone_info *ci)
return __send_discard(ci);
else if (unlikely(bio_op(bio) == REQ_OP_WRITE_SAME))
return __send_write_same(ci);
else if (unlikely(bio_op(bio) == REQ_OP_WRITE_ZEROES))
return __send_write_zeroes(ci);
ti = dm_table_find_target(ci->map, ci->sector);
if (!dm_target_is_valid(ti))

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@ -254,6 +254,12 @@ struct dm_target {
*/
unsigned num_write_same_bios;
/*
* The number of WRITE ZEROES bios that will be submitted to the target.
* The bio number can be accessed with dm_bio_get_target_bio_nr.
*/
unsigned num_write_zeroes_bios;
/*
* The minimum number of extra bytes allocated in each io for the
* target to use.