Refactor raid1_make_request to make read and write code in their own
functions to clean up the code.
Signed-off-by: Robert LeBlanc <robert@xxxxxxxxxxxxx>
---
drivers/md/raid1.c | 244 +++++++++++++++++++++++++++--------------------------
1 file changed, 126 insertions(+), 118 deletions(-)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 21dc00e..5aa0f89 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1032,17 +1032,96 @@ static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
kfree(plug);
}
-static void raid1_make_request(struct mddev *mddev, struct bio * bio)
+static void raid1_read_request(struct mddev *mddev, struct bio *bio,
+ struct r1bio *r1_bio)
{
struct r1conf *conf = mddev->private;
struct raid1_info *mirror;
- struct r1bio *r1_bio;
struct bio *read_bio;
+ struct bitmap *bitmap = mddev->bitmap;
+ const int op = bio_op(bio);
+ const unsigned long do_sync = (bio->bi_opf & REQ_SYNC);
+ int sectors_handled;
+ int max_sectors;
+ int rdisk;
+
+read_again:
+ rdisk = read_balance(conf, r1_bio, &max_sectors);
+
+ if (rdisk < 0) {
+ /* couldn't find anywhere to read from */
+ raid_end_bio_io(r1_bio);
+ return;
+ }
+ mirror = conf->mirrors + rdisk;
+
+ if (test_bit(WriteMostly, &mirror->rdev->flags) &&
+ bitmap) {
+ /* Reading from a write-mostly device must
+ * take care not to over-take any writes
+ * that are 'behind'
+ */
+ wait_event(bitmap->behind_wait,
+ atomic_read(&bitmap->behind_writes) == 0);
+ }
+ r1_bio->read_disk = rdisk;
+ r1_bio->start_next_window = 0;
+
+ read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev);
+ bio_trim(read_bio, r1_bio->sector - bio->bi_iter.bi_sector,
+ max_sectors);
+
+ r1_bio->bios[rdisk] = read_bio;
+
+ read_bio->bi_iter.bi_sector = r1_bio->sector +
+ mirror->rdev->data_offset;
+ read_bio->bi_bdev = mirror->rdev->bdev;
+ read_bio->bi_end_io = raid1_end_read_request;
+ bio_set_op_attrs(read_bio, op, do_sync);
+ read_bio->bi_private = r1_bio;
+
+ if (max_sectors < r1_bio->sectors) {
+ /* could not read all from this device, so we will
+ * need another r1_bio.
+ */
+
+ sectors_handled = (r1_bio->sector + max_sectors
+ - bio->bi_iter.bi_sector);
+ r1_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 __make_request
+ * and subsequent mempool_alloc might block waiting
+ * for it. So hand bio over to raid1d.
+ */
+ reschedule_retry(r1_bio);
+
+ r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO);
+
+ r1_bio->master_bio = bio;
+ r1_bio->sectors = bio_sectors(bio) - sectors_handled;
+ r1_bio->state = 0;
+ r1_bio->mddev = mddev;
+ r1_bio->sector = bio->bi_iter.bi_sector + sectors_handled;
+ goto read_again;
+ } else
+ generic_make_request(read_bio);
+}
+
+static void raid1_write_request(struct mddev *mddev, struct bio *bio,
+ struct r1bio *r1_bio,
+ sector_t start_next_window)
+{
+ struct r1conf *conf = mddev->private;
int i, disks;
- struct bitmap *bitmap;
+ struct bitmap *bitmap = mddev->bitmap;
unsigned long flags;
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_flush_fua = (bio->bi_opf &
(REQ_PREFLUSH | REQ_FUA));
@@ -1052,7 +1131,6 @@ static void raid1_make_request(struct mddev *mddev, struct bio * bio)
int first_clone;
int sectors_handled;
int max_sectors;
- sector_t start_next_window;
/*
* Register the new request and wait if the reconstruction
@@ -1062,12 +1140,11 @@ static void raid1_make_request(struct mddev *mddev, struct bio * bio)
md_write_start(mddev, bio); /* wait on superblock update early */
- if (bio_data_dir(bio) == WRITE &&
- ((bio_end_sector(bio) > mddev->suspend_lo &&
+ if ((bio_end_sector(bio) > mddev->suspend_lo &&
bio->bi_iter.bi_sector < mddev->suspend_hi) ||
(mddev_is_clustered(mddev) &&
md_cluster_ops->area_resyncing(mddev, WRITE,
- bio->bi_iter.bi_sector, bio_end_sector(bio))))) {
+ bio->bi_iter.bi_sector, bio_end_sector(bio)))) {
/* As the suspend_* range is controlled by
* userspace, we want an interruptible
* wait.
@@ -1081,119 +1158,14 @@ static void raid1_make_request(struct mddev *mddev, struct bio * bio)
bio->bi_iter.bi_sector >= mddev->suspend_hi ||
(mddev_is_clustered(mddev) &&
!md_cluster_ops->area_resyncing(mddev, WRITE,
- bio->bi_iter.bi_sector, bio_end_sector(bio))))
+ bio->bi_iter.bi_sector,
+ bio_end_sector(bio))))
break;
schedule();
}
finish_wait(&conf->wait_barrier, &w);
}
- start_next_window = wait_barrier(conf, bio);
-
- bitmap = mddev->bitmap;
-
- /*
- * make_request() can abort the operation when read-ahead is being
- * used and no empty request is available.
- *
- */
- r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO);
-
- r1_bio->master_bio = bio;
- r1_bio->sectors = bio_sectors(bio);
- r1_bio->state = 0;
- r1_bio->mddev = mddev;
- r1_bio->sector = bio->bi_iter.bi_sector;
-
- /* 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 r1_bio and no locking
- * will be needed when requests complete. 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:
- */
- int rdisk;
-
-read_again:
- rdisk = read_balance(conf, r1_bio, &max_sectors);
-
- if (rdisk < 0) {
- /* couldn't find anywhere to read from */
- raid_end_bio_io(r1_bio);
- return;
- }
- mirror = conf->mirrors + rdisk;
-
- if (test_bit(WriteMostly, &mirror->rdev->flags) &&
- bitmap) {
- /* Reading from a write-mostly device must
- * take care not to over-take any writes
- * that are 'behind'
- */
- wait_event(bitmap->behind_wait,
- atomic_read(&bitmap->behind_writes) == 0);
- }
- r1_bio->read_disk = rdisk;
- r1_bio->start_next_window = 0;
-
- read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev);
- bio_trim(read_bio, r1_bio->sector - bio->bi_iter.bi_sector,
- max_sectors);
-
- r1_bio->bios[rdisk] = read_bio;
-
- read_bio->bi_iter.bi_sector = r1_bio->sector +
- mirror->rdev->data_offset;
- read_bio->bi_bdev = mirror->rdev->bdev;
- read_bio->bi_end_io = raid1_end_read_request;
- bio_set_op_attrs(read_bio, op, do_sync);
- read_bio->bi_private = r1_bio;
-
- if (max_sectors < r1_bio->sectors) {
- /* could not read all from this device, so we will
- * need another r1_bio.
- */
-
- sectors_handled = (r1_bio->sector + max_sectors
- - bio->bi_iter.bi_sector);
- r1_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 __make_request
- * and subsequent mempool_alloc might block waiting
- * for it. So hand bio over to raid1d.
- */
- reschedule_retry(r1_bio);
-
- r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO);
-
- r1_bio->master_bio = bio;
- r1_bio->sectors = bio_sectors(bio) - sectors_handled;
- r1_bio->state = 0;
- r1_bio->mddev = mddev;
- r1_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);
wait_event(conf->wait_barrier,
@@ -1236,8 +1208,7 @@ read_again:
int bad_sectors;
int is_bad;
- is_bad = is_badblock(rdev, r1_bio->sector,
- max_sectors,
+ is_bad = is_badblock(rdev, r1_bio->sector, max_sectors,
&first_bad, &bad_sectors);
if (is_bad < 0) {
/* mustn't write here until the bad block is
@@ -1325,7 +1296,8 @@ read_again:
continue;
mbio = bio_clone_mddev(bio, GFP_NOIO, mddev);
- bio_trim(mbio, r1_bio->sector - bio->bi_iter.bi_sector, max_sectors);
+ bio_trim(mbio, r1_bio->sector - bio->bi_iter.bi_sector,
+ max_sectors);
if (first_clone) {
/* do behind I/O ?
@@ -1408,6 +1380,42 @@ read_again:
wake_up(&conf->wait_barrier);
}
+static void raid1_make_request(struct mddev *mddev, struct bio *bio)
+{
+ struct r1conf *conf = mddev->private;
+ struct r1bio *r1_bio;
+ sector_t start_next_window = wait_barrier(conf, bio);
+
+ /*
+ * make_request() can abort the operation when read-ahead is being
+ * used and no empty request is available.
+ *
+ */
+ r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO);
+
+ r1_bio->master_bio = bio;
+ r1_bio->sectors = bio_sectors(bio);
+ r1_bio->state = 0;
+ r1_bio->mddev = mddev;
+ r1_bio->sector = bio->bi_iter.bi_sector;
+
+ /* 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 r1_bio and no locking
+ * will be needed when requests complete. 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) {
+ raid1_read_request(mddev, bio, r1_bio);
+ return;
+ }
+ raid1_write_request(mddev, bio, r1_bio, start_next_window);
+}
+
static void raid1_status(struct seq_file *seq, struct mddev *mddev)
{
struct r1conf *conf = mddev->private;
--
2.10.2
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