X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fmd%2Fraid10.c;h=867f06ae33d944e8ef7178d28fc3fa8905d963b3;hb=fcda46128d5cb50075339b79ce585ab767337e9e;hp=62ebb1bc72be24cc32ecc775c5bd71603d44e5c6;hpb=62778ba1aa2589dc78c36a32edc6f5a6ccaf50c6;p=linux-2.6

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 62ebb1bc72..867f06ae33 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -47,7 +47,7 @@
 
 static void unplug_slaves(mddev_t *mddev);
 
-static void * r10bio_pool_alloc(unsigned int __nocast gfp_flags, void *data)
+static void * r10bio_pool_alloc(gfp_t gfp_flags, void *data)
 {
 	conf_t *conf = data;
 	r10bio_t *r10_bio;
@@ -81,7 +81,7 @@ static void r10bio_pool_free(void *r10_bio, void *data)
  * one for write (we recover only one drive per r10buf)
  *
  */
-static void * r10buf_pool_alloc(unsigned int __nocast gfp_flags, void *data)
+static void * r10buf_pool_alloc(gfp_t gfp_flags, void *data)
 {
 	conf_t *conf = data;
 	struct page *page;
@@ -496,6 +496,7 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
 	int disk, slot, nslot;
 	const int sectors = r10_bio->sectors;
 	sector_t new_distance, current_distance;
+	mdk_rdev_t *rdev;
 
 	raid10_find_phys(conf, r10_bio);
 	rcu_read_lock();
@@ -510,8 +511,8 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
 		slot = 0;
 		disk = r10_bio->devs[slot].devnum;
 
-		while (!conf->mirrors[disk].rdev ||
-		       !conf->mirrors[disk].rdev->in_sync) {
+		while ((rdev = rcu_dereference(conf->mirrors[disk].rdev)) == NULL ||
+		       !test_bit(In_sync, &rdev->flags)) {
 			slot++;
 			if (slot == conf->copies) {
 				slot = 0;
@@ -527,8 +528,8 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
 	/* make sure the disk is operational */
 	slot = 0;
 	disk = r10_bio->devs[slot].devnum;
-	while (!conf->mirrors[disk].rdev ||
-	       !conf->mirrors[disk].rdev->in_sync) {
+	while ((rdev=rcu_dereference(conf->mirrors[disk].rdev)) == NULL ||
+	       !test_bit(In_sync, &rdev->flags)) {
 		slot ++;
 		if (slot == conf->copies) {
 			disk = -1;
@@ -538,7 +539,8 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
 	}
 
 
-	current_distance = abs(this_sector - conf->mirrors[disk].head_position);
+	current_distance = abs(r10_bio->devs[slot].addr -
+			       conf->mirrors[disk].head_position);
 
 	/* Find the disk whose head is closest */
 
@@ -546,11 +548,11 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio)
 		int ndisk = r10_bio->devs[nslot].devnum;
 
 
-		if (!conf->mirrors[ndisk].rdev ||
-		    !conf->mirrors[ndisk].rdev->in_sync)
+		if ((rdev=rcu_dereference(conf->mirrors[ndisk].rdev)) == NULL ||
+		    !test_bit(In_sync, &rdev->flags))
 			continue;
 
-		if (!atomic_read(&conf->mirrors[ndisk].rdev->nr_pending)) {
+		if (!atomic_read(&rdev->nr_pending)) {
 			disk = ndisk;
 			slot = nslot;
 			break;
@@ -568,7 +570,7 @@ rb_out:
 	r10_bio->read_slot = slot;
 /*	conf->next_seq_sect = this_sector + sectors;*/
 
-	if (disk >= 0 && conf->mirrors[disk].rdev)
+	if (disk >= 0 && (rdev=rcu_dereference(conf->mirrors[disk].rdev))!= NULL)
 		atomic_inc(&conf->mirrors[disk].rdev->nr_pending);
 	rcu_read_unlock();
 
@@ -582,8 +584,8 @@ static void unplug_slaves(mddev_t *mddev)
 
 	rcu_read_lock();
 	for (i=0; i<mddev->raid_disks; i++) {
-		mdk_rdev_t *rdev = conf->mirrors[i].rdev;
-		if (rdev && !rdev->faulty && atomic_read(&rdev->nr_pending)) {
+		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
+		if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) {
 			request_queue_t *r_queue = bdev_get_queue(rdev->bdev);
 
 			atomic_inc(&rdev->nr_pending);
@@ -613,8 +615,8 @@ static int raid10_issue_flush(request_queue_t *q, struct gendisk *disk,
 
 	rcu_read_lock();
 	for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-		mdk_rdev_t *rdev = conf->mirrors[i].rdev;
-		if (rdev && !rdev->faulty) {
+		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
+		if (rdev && !test_bit(Faulty, &rdev->flags)) {
 			struct block_device *bdev = rdev->bdev;
 			request_queue_t *r_queue = bdev_get_queue(bdev);
 
@@ -667,6 +669,12 @@ static int make_request(request_queue_t *q, struct bio * bio)
 	struct bio *read_bio;
 	int i;
 	int chunk_sects = conf->chunk_mask + 1;
+	const int rw = bio_data_dir(bio);
+
+	if (unlikely(bio_barrier(bio))) {
+		bio_endio(bio, bio->bi_size, -EOPNOTSUPP);
+		return 0;
+	}
 
 	/* If this request crosses a chunk boundary, we need to
 	 * split it.  This will only happen for 1 PAGE (or less) requests.
@@ -712,13 +720,8 @@ static int make_request(request_queue_t *q, struct bio * bio)
 	conf->nr_pending++;
 	spin_unlock_irq(&conf->resync_lock);
 
-	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));
-	}
+	disk_stat_inc(mddev->gendisk, ios[rw]);
+	disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bio));
 
 	r10_bio = mempool_alloc(conf->r10bio_pool, GFP_NOIO);
 
@@ -728,7 +731,7 @@ static int make_request(request_queue_t *q, struct bio * bio)
 	r10_bio->mddev = mddev;
 	r10_bio->sector = bio->bi_sector;
 
-	if (bio_data_dir(bio) == READ) {
+	if (rw == READ) {
 		/*
 		 * read balancing logic:
 		 */
@@ -766,9 +769,10 @@ static int make_request(request_queue_t *q, struct bio * bio)
 	rcu_read_lock();
 	for (i = 0;  i < conf->copies; i++) {
 		int d = r10_bio->devs[i].devnum;
-		if (conf->mirrors[d].rdev &&
-		    !conf->mirrors[d].rdev->faulty) {
-			atomic_inc(&conf->mirrors[d].rdev->nr_pending);
+		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[d].rdev);
+		if (rdev &&
+		    !test_bit(Faulty, &rdev->flags)) {
+			atomic_inc(&rdev->nr_pending);
 			r10_bio->devs[i].bio = bio;
 		} else
 			r10_bio->devs[i].bio = NULL;
@@ -822,7 +826,7 @@ static void status(struct seq_file *seq, mddev_t *mddev)
 	for (i = 0; i < conf->raid_disks; i++)
 		seq_printf(seq, "%s",
 			      conf->mirrors[i].rdev &&
-			      conf->mirrors[i].rdev->in_sync ? "U" : "_");
+			      test_bit(In_sync, &conf->mirrors[i].rdev->flags) ? "U" : "_");
 	seq_printf(seq, "]");
 }
 
@@ -837,7 +841,7 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev)
 	 * next level up know.
 	 * else mark the drive as failed
 	 */
-	if (rdev->in_sync
+	if (test_bit(In_sync, &rdev->flags)
 	    && conf->working_disks == 1)
 		/*
 		 * Don't fail the drive, just return an IO error.
@@ -847,7 +851,7 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev)
 		 * really dead" tests...
 		 */
 		return;
-	if (rdev->in_sync) {
+	if (test_bit(In_sync, &rdev->flags)) {
 		mddev->degraded++;
 		conf->working_disks--;
 		/*
@@ -855,8 +859,8 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev)
 		 */
 		set_bit(MD_RECOVERY_ERR, &mddev->recovery);
 	}
-	rdev->in_sync = 0;
-	rdev->faulty = 1;
+	clear_bit(In_sync, &rdev->flags);
+	set_bit(Faulty, &rdev->flags);
 	mddev->sb_dirty = 1;
 	printk(KERN_ALERT "raid10: Disk failure on %s, disabling device. \n"
 		"	Operation continuing on %d devices\n",
@@ -881,7 +885,8 @@ static void print_conf(conf_t *conf)
 		tmp = conf->mirrors + i;
 		if (tmp->rdev)
 			printk(" disk %d, wo:%d, o:%d, dev:%s\n",
-				i, !tmp->rdev->in_sync, !tmp->rdev->faulty,
+				i, !test_bit(In_sync, &tmp->rdev->flags),
+			        !test_bit(Faulty, &tmp->rdev->flags),
 				bdevname(tmp->rdev->bdev,b));
 	}
 }
@@ -900,6 +905,27 @@ static void close_sync(conf_t *conf)
 	conf->r10buf_pool = NULL;
 }
 
+/* check if there are enough drives for
+ * every block to appear on atleast one
+ */
+static int enough(conf_t *conf)
+{
+	int first = 0;
+
+	do {
+		int n = conf->copies;
+		int cnt = 0;
+		while (n--) {
+			if (conf->mirrors[first].rdev)
+				cnt++;
+			first = (first+1) % conf->raid_disks;
+		}
+		if (cnt == 0)
+			return 0;
+	} while (first != 0);
+	return 1;
+}
+
 static int raid10_spare_active(mddev_t *mddev)
 {
 	int i;
@@ -913,11 +939,11 @@ static int raid10_spare_active(mddev_t *mddev)
 	for (i = 0; i < conf->raid_disks; i++) {
 		tmp = conf->mirrors + i;
 		if (tmp->rdev
-		    && !tmp->rdev->faulty
-		    && !tmp->rdev->in_sync) {
+		    && !test_bit(Faulty, &tmp->rdev->flags)
+		    && !test_bit(In_sync, &tmp->rdev->flags)) {
 			conf->working_disks++;
 			mddev->degraded--;
-			tmp->rdev->in_sync = 1;
+			set_bit(In_sync, &tmp->rdev->flags);
 		}
 	}
 
@@ -938,6 +964,8 @@ static int raid10_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 		 * very different from resync
 		 */
 		return 0;
+	if (!enough(conf))
+		return 0;
 
 	for (mirror=0; mirror < mddev->raid_disks; mirror++)
 		if ( !(p=conf->mirrors+mirror)->rdev) {
@@ -955,7 +983,7 @@ static int raid10_add_disk(mddev_t *mddev, mdk_rdev_t *rdev)
 			p->head_position = 0;
 			rdev->raid_disk = mirror;
 			found = 1;
-			p->rdev = rdev;
+			rcu_assign_pointer(p->rdev, rdev);
 			break;
 		}
 
@@ -973,7 +1001,7 @@ static int raid10_remove_disk(mddev_t *mddev, int number)
 	print_conf(conf);
 	rdev = p->rdev;
 	if (rdev) {
-		if (rdev->in_sync ||
+		if (test_bit(In_sync, &rdev->flags) ||
 		    atomic_read(&rdev->nr_pending)) {
 			err = -EBUSY;
 			goto abort;
@@ -1389,7 +1417,7 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
 
 		for (i=0 ; i<conf->raid_disks; i++)
 			if (conf->mirrors[i].rdev &&
-			    !conf->mirrors[i].rdev->in_sync) {
+			    !test_bit(In_sync, &conf->mirrors[i].rdev->flags)) {
 				/* want to reconstruct this device */
 				r10bio_t *rb2 = r10_bio;
 
@@ -1410,7 +1438,7 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
 				for (j=0; j<conf->copies;j++) {
 					int d = r10_bio->devs[j].devnum;
 					if (conf->mirrors[d].rdev &&
-					    conf->mirrors[d].rdev->in_sync) {
+					    test_bit(In_sync, &conf->mirrors[d].rdev->flags)) {
 						/* This is where we read from */
 						bio = r10_bio->devs[0].bio;
 						bio->bi_next = biolist;
@@ -1445,7 +1473,13 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
 					}
 				}
 				if (j == conf->copies) {
-					BUG();
+					/* Cannot recover, so abort the recovery */
+					put_buf(r10_bio);
+					r10_bio = rb2;
+					if (!test_and_set_bit(MD_RECOVERY_ERR, &mddev->recovery))
+						printk(KERN_INFO "raid10: %s: insufficient working devices for recovery.\n",
+						       mdname(mddev));
+					break;
 				}
 			}
 		if (biolist == NULL) {
@@ -1480,7 +1514,7 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
 			bio = r10_bio->devs[i].bio;
 			bio->bi_end_io = NULL;
 			if (conf->mirrors[d].rdev == NULL ||
-			    conf->mirrors[d].rdev->faulty)
+			    test_bit(Faulty, &conf->mirrors[d].rdev->flags))
 				continue;
 			atomic_inc(&conf->mirrors[d].rdev->nr_pending);
 			atomic_inc(&r10_bio->remaining);
@@ -1666,7 +1700,7 @@ static int run(mddev_t *mddev)
 			mddev->queue->max_sectors = (PAGE_SIZE>>9);
 
 		disk->head_position = 0;
-		if (!rdev->faulty && rdev->in_sync)
+		if (!test_bit(Faulty, &rdev->flags) && test_bit(In_sync, &rdev->flags))
 			conf->working_disks++;
 	}
 	conf->raid_disks = mddev->raid_disks;
@@ -1678,9 +1712,10 @@ static int run(mddev_t *mddev)
 	init_waitqueue_head(&conf->wait_idle);
 	init_waitqueue_head(&conf->wait_resume);
 
-	if (!conf->working_disks) {
-		printk(KERN_ERR "raid10: no operational mirrors for %s\n",
-			mdname(mddev));
+	/* need to check that every block has at least one working mirror */
+	if (!enough(conf)) {
+		printk(KERN_ERR "raid10: not enough operational mirrors for %s\n",
+		       mdname(mddev));
 		goto out_free_conf;
 	}