return NULL;
}
-static int make_request(struct request_queue *q, struct bio * bio)
+static int make_request(mddev_t *mddev, struct bio * bio)
{
- mddev_t *mddev = q->queuedata;
conf_t *conf = mddev->private;
mirror_info_t *mirror;
r1bio_t *r1_bio;
}
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;
read_bio = bio_clone(bio, GFP_NOIO);
set_bit(R1BIO_Degraded, &r1_bio->state);
}
- /* do behind I/O ? */
+ /* do behind I/O ?
+ * Not if there are too many, or cannot allocate memory,
+ * or a reader on WriteMostly is waiting for behind writes
+ * to flush */
if (bitmap &&
(atomic_read(&bitmap->behind_writes)
< mddev->bitmap_info.max_write_behind) &&
+ !waitqueue_active(&bitmap->behind_wait) &&
(behind_pages = alloc_behind_pages(bio)) != NULL)
set_bit(R1BIO_BehindIO, &r1_bio->state);
r1_bio->bios[r1_bio->read_disk] = bio;
rdev = conf->mirrors[disk].rdev;
if (printk_ratelimit())
- printk(KERN_ERR "raid1: %s: redirecting sector %llu to"
- " another mirror\n",
- bdevname(rdev->bdev,b),
- (unsigned long long)r1_bio->sector);
+ printk(KERN_ERR "raid1: redirecting sector %llu to"
+ " other mirror: %s\n",
+ (unsigned long long)r1_bio->sector,
+ bdevname(rdev->bdev,b));
bio->bi_sector = r1_bio->sector + rdev->data_offset;
bio->bi_bdev = rdev->bdev;
bio->bi_end_io = raid1_end_read_request;
{
conf_t *conf = mddev->private;
struct bitmap *bitmap = mddev->bitmap;
- int behind_wait = 0;
/* wait for behind writes to complete */
- while (bitmap && atomic_read(&bitmap->behind_writes) > 0) {
- behind_wait++;
- printk(KERN_INFO "raid1: behind writes in progress on device %s, waiting to stop (%d)\n", mdname(mddev), behind_wait);
- set_current_state(TASK_UNINTERRUPTIBLE);
- schedule_timeout(HZ); /* wait a second */
+ if (bitmap && atomic_read(&bitmap->behind_writes) > 0) {
+ printk(KERN_INFO "raid1: behind writes in progress on device %s, waiting to stop.\n", mdname(mddev));
/* need to kick something here to make sure I/O goes? */
+ wait_event(bitmap->behind_wait,
+ atomic_read(&bitmap->behind_writes) == 0);
}
raise_barrier(conf);