static void multipathd(struct md_thread *thread)
{
for (;;) {
if ((mp_bh->path = multipath_map (conf))<0) {
printk(KERN_ERR "multipath: %s: redirecting sector %llu"
" to another IO path\n",
bdevname(bio->bi_bdev,b),
(unsigned long long)bio->bi_iter.bi_sector);
}
}
}
static int multipath_make_request (struct request_queue *q, struct bio * bio)
{
mddev_t *mddev = q->queuedata;
multipath_conf_t *conf = mddev_to_conf(mddev);
struct multipath_bh * mp_bh;
struct multipath_info *multipath;
const int rw = bio_data_dir(bio);
int cpu;
if (unlikely(bio_barrier(bio))) {
bio_endio(bio, -EOPNOTSUPP);
return 0;
}
mp_bh = mempool_alloc(conf->pool, GFP_NOIO);
mp_bh->master_bio = bio;
mp_bh->mddev = mddev;
cpu = part_stat_lock();
part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]);
part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw],
bio_sectors(bio));
part_stat_unlock();
mp_bh->path = multipath_map(conf);
if (mp_bh->path < 0) {
bio_endio(bio, -EIO);
mempool_free(mp_bh, conf->pool);
return 0;
}
multipath = conf->multipaths + mp_bh->path;
mp_bh->bio = *bio;
mp_bh->bio.bi_sector += multipath->rdev->data_offset;
mp_bh->bio.bi_bdev = multipath->rdev->bdev;
mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT);
mp_bh->bio.bi_end_io = multipath_end_request;
mp_bh->bio.bi_private = mp_bh;
generic_make_request(&mp_bh->bio);
return 0;
}
static int multipath_make_request (request_queue_t *q, struct bio * bio)
{
mddev_t *mddev = q->queuedata;
multipath_conf_t *conf = mddev_to_conf(mddev);
struct multipath_bh * mp_bh;
struct multipath_info *multipath;
if (unlikely(bio_barrier(bio))) {
bio_endio(bio, bio->bi_size, -EOPNOTSUPP);
return 0;
}
mp_bh = mempool_alloc(conf->pool, GFP_NOIO);
mp_bh->master_bio = bio;
mp_bh->mddev = mddev;
if (bio_data_dir(bio)==WRITE) {
disk_stat_inc(mddev->gendisk, writes);
disk_stat_add(mddev->gendisk, write_sectors, bio_sectors(bio));
} else {
disk_stat_inc(mddev->gendisk, reads);
disk_stat_add(mddev->gendisk, read_sectors, bio_sectors(bio));
}
mp_bh->path = multipath_map(conf);
if (mp_bh->path < 0) {
bio_endio(bio, bio->bi_size, -EIO);
mempool_free(mp_bh, conf->pool);
return 0;
}
multipath = conf->multipaths + mp_bh->path;
mp_bh->bio = *bio;
mp_bh->bio.bi_bdev = multipath->rdev->bdev;
mp_bh->bio.bi_rw |= (1 << BIO_RW_FAILFAST);
mp_bh->bio.bi_end_io = multipath_end_request;
mp_bh->bio.bi_private = mp_bh;
generic_make_request(&mp_bh->bio);
return 0;
}
