Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
[safe/jmp/linux-2.6] / drivers / md / multipath.c
index 14da37f..41ced0c 100644 (file)
  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/raid/multipath.h>
-#include <linux/buffer_head.h>
-#include <asm/atomic.h>
-
-#define MAJOR_NR MD_MAJOR
-#define MD_DRIVER
-#define MD_PERSONALITY
+#include <linux/blkdev.h>
+#include <linux/raid/md_u.h>
+#include <linux/seq_file.h>
+#include "md.h"
+#include "multipath.h"
 
 #define MAX_WORK_PER_DISK 128
 
@@ -82,21 +77,17 @@ static void multipath_end_bh_io (struct multipath_bh *mp_bh, int err)
        struct bio *bio = mp_bh->master_bio;
        multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev);
 
-       bio_endio(bio, bio->bi_size, err);
+       bio_endio(bio, err);
        mempool_free(mp_bh, conf->pool);
 }
 
-static int multipath_end_request(struct bio *bio, unsigned int bytes_done,
-                                int error)
+static void multipath_end_request(struct bio *bio, int error)
 {
        int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
        struct multipath_bh * mp_bh = (struct multipath_bh *)(bio->bi_private);
        multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev);
        mdk_rdev_t *rdev = conf->multipaths[mp_bh->path].rdev;
 
-       if (bio->bi_size)
-               return 1;
-
        if (uptodate)
                multipath_end_bh_io(mp_bh, 0);
        else if (!bio_rw_ahead(bio)) {
@@ -112,7 +103,6 @@ static int multipath_end_request(struct bio *bio, unsigned int bytes_done,
        } else
                multipath_end_bh_io(mp_bh, error);
        rdev_dec_pending(rdev, conf->mddev);
-       return 0;
 }
 
 static void unplug_slaves(mddev_t *mddev)
@@ -125,13 +115,12 @@ static void unplug_slaves(mddev_t *mddev)
                mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
                if (rdev && !test_bit(Faulty, &rdev->flags)
                    && atomic_read(&rdev->nr_pending)) {
-                       request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
+                       struct request_queue *r_queue = bdev_get_queue(rdev->bdev);
 
                        atomic_inc(&rdev->nr_pending);
                        rcu_read_unlock();
 
-                       if (r_queue->unplug_fn)
-                               r_queue->unplug_fn(r_queue);
+                       blk_unplug(r_queue);
 
                        rdev_dec_pending(rdev, mddev);
                        rcu_read_lock();
@@ -140,22 +129,23 @@ static void unplug_slaves(mddev_t *mddev)
        rcu_read_unlock();
 }
 
-static void multipath_unplug(request_queue_t *q)
+static void multipath_unplug(struct request_queue *q)
 {
        unplug_slaves(q->queuedata);
 }
 
 
-static int multipath_make_request (request_queue_t *q, struct bio * bio)
+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, bio->bi_size, -EOPNOTSUPP);
+               bio_endio(bio, -EOPNOTSUPP);
                return 0;
        }
 
@@ -164,12 +154,15 @@ static int multipath_make_request (request_queue_t *q, struct bio * bio)
        mp_bh->master_bio = bio;
        mp_bh->mddev = mddev;
 
-       disk_stat_inc(mddev->gendisk, ios[rw]);
-       disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio));
+       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, bio->bi_size, -EIO);
+               bio_endio(bio, -EIO);
                mempool_free(mp_bh, conf->pool);
                return 0;
        }
@@ -178,7 +171,7 @@ static int multipath_make_request (request_queue_t *q, struct bio * bio)
        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);
+       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);
@@ -199,35 +192,6 @@ static void multipath_status (struct seq_file *seq, mddev_t *mddev)
        seq_printf (seq, "]");
 }
 
-static int multipath_issue_flush(request_queue_t *q, struct gendisk *disk,
-                                sector_t *error_sector)
-{
-       mddev_t *mddev = q->queuedata;
-       multipath_conf_t *conf = mddev_to_conf(mddev);
-       int i, ret = 0;
-
-       rcu_read_lock();
-       for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-               mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
-               if (rdev && !test_bit(Faulty, &rdev->flags)) {
-                       struct block_device *bdev = rdev->bdev;
-                       request_queue_t *r_queue = bdev_get_queue(bdev);
-
-                       if (!r_queue->issue_flush_fn)
-                               ret = -EOPNOTSUPP;
-                       else {
-                               atomic_inc(&rdev->nr_pending);
-                               rcu_read_unlock();
-                               ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
-                                                             error_sector);
-                               rdev_dec_pending(rdev, mddev);
-                               rcu_read_lock();
-                       }
-               }
-       }
-       rcu_read_unlock();
-       return ret;
-}
 static int multipath_congested(void *data, int bits)
 {
        mddev_t *mddev = data;
@@ -238,7 +202,7 @@ static int multipath_congested(void *data, int bits)
        for (i = 0; i < mddev->raid_disks ; i++) {
                mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
                if (rdev && !test_bit(Faulty, &rdev->flags)) {
-                       request_queue_t *q = bdev_get_queue(rdev->bdev);
+                       struct request_queue *q = bdev_get_queue(rdev->bdev);
 
                        ret |= bdi_congested(&q->backing_dev_info, bits);
                        /* Just like multipath_map, we just check the
@@ -279,7 +243,8 @@ static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev)
                        conf->working_disks--;
                        mddev->degraded++;
                        printk(KERN_ALERT "multipath: IO failure on %s,"
-                               " disabling IO path. \n Operation continuing"
+                               " disabling IO path.\n"
+                               "multipath: Operation continuing"
                                " on %d IO paths.\n",
                                bdevname (rdev->bdev,b),
                                conf->working_disks);
@@ -315,13 +280,18 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 {
        multipath_conf_t *conf = mddev->private;
        struct request_queue *q;
-       int found = 0;
+       int err = -EEXIST;
        int path;
        struct multipath_info *p;
+       int first = 0;
+       int last = mddev->raid_disks - 1;
+
+       if (rdev->raid_disk >= 0)
+               first = last = rdev->raid_disk;
 
        print_multipath_conf(conf);
 
-       for (path=0; path<mddev->raid_disks; path++) 
+       for (path = first; path <= last; path++)
                if ((p=conf->multipaths+path)->rdev == NULL) {
                        q = rdev->bdev->bd_disk->queue;
                        blk_queue_stack_limits(mddev->queue, q);
@@ -341,11 +311,13 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
                        rdev->raid_disk = path;
                        set_bit(In_sync, &rdev->flags);
                        rcu_assign_pointer(p->rdev, rdev);
-                       found = 1;
+                       err = 0;
+                       break;
                }
 
        print_multipath_conf(conf);
-       return found;
+
+       return err;
 }
 
 static int multipath_remove_disk(mddev_t *mddev, int number)
@@ -361,7 +333,8 @@ static int multipath_remove_disk(mddev_t *mddev, int number)
        if (rdev) {
                if (test_bit(In_sync, &rdev->flags) ||
                    atomic_read(&rdev->nr_pending)) {
-                       printk(KERN_ERR "hot-remove-disk, slot %d is identified"                                " but is still operational!\n", number);
+                       printk(KERN_ERR "hot-remove-disk, slot %d is identified"
+                              " but is still operational!\n", number);
                        err = -EBUSY;
                        goto abort;
                }
@@ -424,7 +397,7 @@ static void multipathd (mddev_t *mddev)
                        *bio = *(mp_bh->master_bio);
                        bio->bi_sector += conf->multipaths[mp_bh->path].rdev->data_offset;
                        bio->bi_bdev = conf->multipaths[mp_bh->path].rdev->bdev;
-                       bio->bi_rw |= (1 << BIO_RW_FAILFAST);
+                       bio->bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT);
                        bio->bi_end_io = multipath_end_request;
                        bio->bi_private = mp_bh;
                        generic_make_request(bio);
@@ -433,13 +406,20 @@ static void multipathd (mddev_t *mddev)
        spin_unlock_irqrestore(&conf->device_lock, flags);
 }
 
+static sector_t multipath_size(mddev_t *mddev, sector_t sectors, int raid_disks)
+{
+       WARN_ONCE(sectors || raid_disks,
+                 "%s does not support generic reshape\n", __func__);
+
+       return mddev->dev_sectors;
+}
+
 static int multipath_run (mddev_t *mddev)
 {
        multipath_conf_t *conf;
        int disk_idx;
        struct multipath_info *disk;
        mdk_rdev_t *rdev;
-       struct list_head *tmp;
 
        if (mddev->level != LEVEL_MULTIPATH) {
                printk("multipath: %s: raid level not set to multipath IO (%d)\n",
@@ -451,6 +431,7 @@ static int multipath_run (mddev_t *mddev)
         * bookkeeping area. [whatever we allocate in multipath_run(),
         * should be freed in multipath_stop()]
         */
+       mddev->queue->queue_lock = &mddev->queue->__queue_lock;
 
        conf = kzalloc(sizeof(multipath_conf_t), GFP_KERNEL);
        mddev->private = conf;
@@ -471,7 +452,7 @@ static int multipath_run (mddev_t *mddev)
        }
 
        conf->working_disks = 0;
-       ITERATE_RDEV(mddev,rdev,tmp) {
+       list_for_each_entry(rdev, &mddev->disks, same_set) {
                disk_idx = rdev->raid_disk;
                if (disk_idx < 0 ||
                    disk_idx >= mddev->raid_disks)
@@ -529,10 +510,9 @@ static int multipath_run (mddev_t *mddev)
        /*
         * Ok, everything is just fine now
         */
-       mddev->array_size = mddev->size;
+       md_set_array_sectors(mddev, multipath_size(mddev, 0, 0));
 
        mddev->queue->unplug_fn = multipath_unplug;
-       mddev->queue->issue_flush_fn = multipath_issue_flush;
        mddev->queue->backing_dev_info.congested_fn = multipath_congested;
        mddev->queue->backing_dev_info.congested_data = mddev;
 
@@ -575,6 +555,7 @@ static struct mdk_personality multipath_personality =
        .error_handler  = multipath_error,
        .hot_add_disk   = multipath_add_disk,
        .hot_remove_disk= multipath_remove_disk,
+       .size           = multipath_size,
 };
 
 static int __init multipath_init (void)