md/raid10: Refactor raid10_make_request

Refactor raid10_make_request into seperate read and write functions to
clean up the code.

Shaohua: add the recovery check back to read path

Signed-off-by: Robert LeBlanc <robert@leblancnet.us>
Signed-off-by: Shaohua Li <shli@fb.com>
This commit is contained in:
Robert LeBlanc 2016-12-05 13:02:58 -07:00 committed by Shaohua Li
parent 3b046a97cb
commit bb5f1ed70b
1 changed files with 140 additions and 105 deletions

View File

@ -1087,23 +1087,122 @@ static void raid10_unplug(struct blk_plug_cb *cb, bool from_schedule)
kfree(plug);
}
static void __make_request(struct mddev *mddev, struct bio *bio)
static void raid10_read_request(struct mddev *mddev, struct bio *bio,
struct r10bio *r10_bio)
{
struct r10conf *conf = mddev->private;
struct r10bio *r10_bio;
struct bio *read_bio;
const int op = bio_op(bio);
const unsigned long do_sync = (bio->bi_opf & REQ_SYNC);
int sectors_handled;
int max_sectors;
sector_t sectors;
struct md_rdev *rdev;
int slot;
/*
* Register the new request and wait if the reconstruction
* thread has put up a bar for new requests.
* Continue immediately if no resync is active currently.
*/
wait_barrier(conf);
sectors = bio_sectors(bio);
while (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
bio->bi_iter.bi_sector < conf->reshape_progress &&
bio->bi_iter.bi_sector + sectors > conf->reshape_progress) {
/*
* IO spans the reshape position. Need to wait for reshape to
* pass
*/
raid10_log(conf->mddev, "wait reshape");
allow_barrier(conf);
wait_event(conf->wait_barrier,
conf->reshape_progress <= bio->bi_iter.bi_sector ||
conf->reshape_progress >= bio->bi_iter.bi_sector +
sectors);
wait_barrier(conf);
}
read_again:
rdev = read_balance(conf, r10_bio, &max_sectors);
if (!rdev) {
raid_end_bio_io(r10_bio);
return;
}
slot = r10_bio->read_slot;
read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev);
bio_trim(read_bio, r10_bio->sector - bio->bi_iter.bi_sector,
max_sectors);
r10_bio->devs[slot].bio = read_bio;
r10_bio->devs[slot].rdev = rdev;
read_bio->bi_iter.bi_sector = r10_bio->devs[slot].addr +
choose_data_offset(r10_bio, rdev);
read_bio->bi_bdev = rdev->bdev;
read_bio->bi_end_io = raid10_end_read_request;
bio_set_op_attrs(read_bio, op, do_sync);
if (test_bit(FailFast, &rdev->flags) &&
test_bit(R10BIO_FailFast, &r10_bio->state))
read_bio->bi_opf |= MD_FAILFAST;
read_bio->bi_private = r10_bio;
if (mddev->gendisk)
trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev),
read_bio, disk_devt(mddev->gendisk),
r10_bio->sector);
if (max_sectors < r10_bio->sectors) {
/*
* Could not read all from this device, so we will need another
* r10_bio.
*/
sectors_handled = (r10_bio->sector + max_sectors
- bio->bi_iter.bi_sector);
r10_bio->sectors = max_sectors;
spin_lock_irq(&conf->device_lock);
if (bio->bi_phys_segments == 0)
bio->bi_phys_segments = 2;
else
bio->bi_phys_segments++;
spin_unlock_irq(&conf->device_lock);
/*
* Cannot call generic_make_request directly as that will be
* queued in __generic_make_request and subsequent
* mempool_alloc might block waiting for it. so hand bio over
* to raid10d.
*/
reschedule_retry(r10_bio);
r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO);
r10_bio->master_bio = bio;
r10_bio->sectors = bio_sectors(bio) - sectors_handled;
r10_bio->state = 0;
r10_bio->mddev = mddev;
r10_bio->sector = bio->bi_iter.bi_sector + sectors_handled;
goto read_again;
} else
generic_make_request(read_bio);
return;
}
static void raid10_write_request(struct mddev *mddev, struct bio *bio,
struct r10bio *r10_bio)
{
struct r10conf *conf = mddev->private;
int i;
const int op = bio_op(bio);
const int rw = bio_data_dir(bio);
const unsigned long do_sync = (bio->bi_opf & REQ_SYNC);
const unsigned long do_fua = (bio->bi_opf & REQ_FUA);
unsigned long flags;
struct md_rdev *blocked_rdev;
struct blk_plug_cb *cb;
struct raid10_plug_cb *plug = NULL;
sector_t sectors;
int sectors_handled;
int max_sectors;
int sectors;
md_write_start(mddev, bio);
@ -1118,8 +1217,9 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
while (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
bio->bi_iter.bi_sector < conf->reshape_progress &&
bio->bi_iter.bi_sector + sectors > conf->reshape_progress) {
/* IO spans the reshape position. Need to wait for
* reshape to pass
/*
* IO spans the reshape position. Need to wait for reshape to
* pass
*/
raid10_log(conf->mddev, "wait reshape");
allow_barrier(conf);
@ -1129,8 +1229,8 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
sectors);
wait_barrier(conf);
}
if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) &&
bio_data_dir(bio) == WRITE &&
(mddev->reshape_backwards
? (bio->bi_iter.bi_sector < conf->reshape_safe &&
bio->bi_iter.bi_sector + sectors > conf->reshape_progress)
@ -1148,98 +1248,6 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
conf->reshape_safe = mddev->reshape_position;
}
r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO);
r10_bio->master_bio = bio;
r10_bio->sectors = sectors;
r10_bio->mddev = mddev;
r10_bio->sector = bio->bi_iter.bi_sector;
r10_bio->state = 0;
/* We might need to issue multiple reads to different
* devices if there are bad blocks around, so we keep
* track of the number of reads in bio->bi_phys_segments.
* If this is 0, there is only one r10_bio and no locking
* will be needed when the request completes. If it is
* non-zero, then it is the number of not-completed requests.
*/
bio->bi_phys_segments = 0;
bio_clear_flag(bio, BIO_SEG_VALID);
if (rw == READ) {
/*
* read balancing logic:
*/
struct md_rdev *rdev;
int slot;
read_again:
rdev = read_balance(conf, r10_bio, &max_sectors);
if (!rdev) {
raid_end_bio_io(r10_bio);
return;
}
slot = r10_bio->read_slot;
read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev);
bio_trim(read_bio, r10_bio->sector - bio->bi_iter.bi_sector,
max_sectors);
r10_bio->devs[slot].bio = read_bio;
r10_bio->devs[slot].rdev = rdev;
read_bio->bi_iter.bi_sector = r10_bio->devs[slot].addr +
choose_data_offset(r10_bio, rdev);
read_bio->bi_bdev = rdev->bdev;
read_bio->bi_end_io = raid10_end_read_request;
bio_set_op_attrs(read_bio, op, do_sync);
if (test_bit(FailFast, &rdev->flags) &&
test_bit(R10BIO_FailFast, &r10_bio->state))
read_bio->bi_opf |= MD_FAILFAST;
read_bio->bi_private = r10_bio;
if (mddev->gendisk)
trace_block_bio_remap(bdev_get_queue(read_bio->bi_bdev),
read_bio, disk_devt(mddev->gendisk),
r10_bio->sector);
if (max_sectors < r10_bio->sectors) {
/* Could not read all from this device, so we will
* need another r10_bio.
*/
sectors_handled = (r10_bio->sector + max_sectors
- bio->bi_iter.bi_sector);
r10_bio->sectors = max_sectors;
spin_lock_irq(&conf->device_lock);
if (bio->bi_phys_segments == 0)
bio->bi_phys_segments = 2;
else
bio->bi_phys_segments++;
spin_unlock_irq(&conf->device_lock);
/* Cannot call generic_make_request directly
* as that will be queued in __generic_make_request
* and subsequent mempool_alloc might block
* waiting for it. so hand bio over to raid10d.
*/
reschedule_retry(r10_bio);
r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO);
r10_bio->master_bio = bio;
r10_bio->sectors = bio_sectors(bio) - sectors_handled;
r10_bio->state = 0;
r10_bio->mddev = mddev;
r10_bio->sector = bio->bi_iter.bi_sector +
sectors_handled;
goto read_again;
} else
generic_make_request(read_bio);
return;
}
/*
* WRITE:
*/
if (conf->pending_count >= max_queued_requests) {
md_wakeup_thread(mddev->thread);
raid10_log(mddev, "wait queued");
@ -1300,8 +1308,7 @@ retry_write:
int bad_sectors;
int is_bad;
is_bad = is_badblock(rdev, dev_sector,
max_sectors,
is_bad = is_badblock(rdev, dev_sector, max_sectors,
&first_bad, &bad_sectors);
if (is_bad < 0) {
/* Mustn't write here until the bad block
@ -1405,8 +1412,7 @@ retry_write:
r10_bio->devs[i].bio = mbio;
mbio->bi_iter.bi_sector = (r10_bio->devs[i].addr+
choose_data_offset(r10_bio,
rdev));
choose_data_offset(r10_bio, rdev));
mbio->bi_bdev = rdev->bdev;
mbio->bi_end_io = raid10_end_write_request;
bio_set_op_attrs(mbio, op, do_sync | do_fua);
@ -1457,8 +1463,7 @@ retry_write:
r10_bio->devs[i].repl_bio = mbio;
mbio->bi_iter.bi_sector = (r10_bio->devs[i].addr +
choose_data_offset(
r10_bio, rdev));
choose_data_offset(r10_bio, rdev));
mbio->bi_bdev = rdev->bdev;
mbio->bi_end_io = raid10_end_write_request;
bio_set_op_attrs(mbio, op, do_sync | do_fua);
@ -1503,6 +1508,36 @@ retry_write:
one_write_done(r10_bio);
}
static void __make_request(struct mddev *mddev, struct bio *bio)
{
struct r10conf *conf = mddev->private;
struct r10bio *r10_bio;
r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO);
r10_bio->master_bio = bio;
r10_bio->sectors = bio_sectors(bio);
r10_bio->mddev = mddev;
r10_bio->sector = bio->bi_iter.bi_sector;
r10_bio->state = 0;
/*
* We might need to issue multiple reads to different devices if there
* are bad blocks around, so we keep track of the number of reads in
* bio->bi_phys_segments. If this is 0, there is only one r10_bio and
* no locking will be needed when the request completes. If it is
* non-zero, then it is the number of not-completed requests.
*/
bio->bi_phys_segments = 0;
bio_clear_flag(bio, BIO_SEG_VALID);
if (bio_data_dir(bio) == READ)
raid10_read_request(mddev, bio, r10_bio);
else
raid10_write_request(mddev, bio, r10_bio);
}
static void raid10_make_request(struct mddev *mddev, struct bio *bio)
{
struct r10conf *conf = mddev->private;