1 files changed, 147 insertions, 100 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 3b4d69c0562301..dc9d2def0270df 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -271,7 +271,7 @@ static int raid1_end_read_request(struct bio *bio, unsigned int bytes_done, int
 	 */
 	update_head_pos(mirror, r1_bio);
 
-	if (uptodate || conf->working_disks <= 1) {
+	if (uptodate || (conf->raid_disks - conf->mddev->degraded) <= 1) {
 		/*
 		 * Set R1BIO_Uptodate in our master bio, so that
 		 * we will return a good error code for to the higher
@@ -601,6 +601,32 @@ static int raid1_issue_flush(request_queue_t *q, struct gendisk *disk,
 	return ret;
 }
 
+static int raid1_congested(void *data, int bits)
+{
+	mddev_t *mddev = data;
+	conf_t *conf = mddev_to_conf(mddev);
+	int i, ret = 0;
+
+	rcu_read_lock();
+	for (i = 0; i < mddev->raid_disks; i++) {
+		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
+		if (rdev && !test_bit(Faulty, &rdev->flags)) {
+			request_queue_t *q = bdev_get_queue(rdev->bdev);
+
+			/* Note the '|| 1' - when read_balance prefers
+			 * non-congested targets, it can be removed
+			 */
+			if ((bits & (1<<BDI_write_congested)) || 1)
+				ret |= bdi_congested(&q->backing_dev_info, bits);
+			else
+				ret &= bdi_congested(&q->backing_dev_info, bits);
+		}
+	}
+	rcu_read_unlock();
+	return ret;
+}
+
+
 /* Barriers....
  * Sometimes we need to suspend IO while we do something else,
  * either some resync/recovery, or reconfigure the array.
@@ -929,7 +955,7 @@ static void status(struct seq_file *seq, mddev_t *mddev)
 	int i;
 
 	seq_printf(seq, " [%d/%d] [", conf->raid_disks,
-						conf->working_disks);
+		   conf->raid_disks - mddev->degraded);
 	rcu_read_lock();
 	for (i = 0; i < conf->raid_disks; i++) {
 		mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
@@ -953,26 +979,27 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev)
 	 * else mark the drive as failed
 	 */
 	if (test_bit(In_sync, &rdev->flags)
-	    && conf->working_disks == 1)
+	    && (conf->raid_disks - mddev->degraded) == 1)
 		/*
 		 * Don't fail the drive, act as though we were just a
 		 * normal single drive
 		 */
 		return;
-	if (test_bit(In_sync, &rdev->flags)) {
+	if (test_and_clear_bit(In_sync, &rdev->flags)) {
+		unsigned long flags;
+		spin_lock_irqsave(&conf->device_lock, flags);
 		mddev->degraded++;
-		conf->working_disks--;
+		spin_unlock_irqrestore(&conf->device_lock, flags);
 		/*
 		 * if recovery is running, make sure it aborts.
 		 */
 		set_bit(MD_RECOVERY_ERR, &mddev->recovery);
 	}
-	clear_bit(In_sync, &rdev->flags);
 	set_bit(Faulty, &rdev->flags);
-	mddev->sb_dirty = 1;
+	set_bit(MD_CHANGE_DEVS, &mddev->flags);
 	printk(KERN_ALERT "raid1: Disk failure on %s, disabling device. \n"
 		"	Operation continuing on %d devices\n",
-		bdevname(rdev->bdev,b), conf->working_disks);
+		bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded);
 }
 
 static void print_conf(conf_t *conf)
@@ -984,7 +1011,7 @@ static void print_conf(conf_t *conf)
 		printk("(!conf)\n");
 		return;
 	}
-	printk(" --- wd:%d rd:%d\n", conf->working_disks,
+	printk(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
 		conf->raid_disks);
 
 	rcu_read_lock();
@@ -1023,10 +1050,11 @@ static int raid1_spare_active(mddev_t *mddev)
 		mdk_rdev_t *rdev = conf->mirrors[i].rdev;
 		if (rdev
 		    && !test_bit(Faulty, &rdev->flags)
-		    && !test_bit(In_sync, &rdev->flags)) {
-			conf->working_disks++;
+		    && !test_and_set_bit(In_sync, &rdev->flags)) {
+			unsigned long flags;
+			spin_lock_irqsave(&conf->device_lock, flags);
 			mddev->degraded--;
-			set_bit(In_sync, &rdev->flags);
+			spin_unlock_irqrestore(&conf->device_lock, flags);
 		}
 	}
 
@@ -1368,6 +1396,95 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)
  *	3.	Performs writes following reads for array syncronising.
  */
 
+static void fix_read_error(conf_t *conf, int read_disk,
+			   sector_t sect, int sectors)
+{
+	mddev_t *mddev = conf->mddev;
+	while(sectors) {
+		int s = sectors;
+		int d = read_disk;
+		int success = 0;
+		int start;
+		mdk_rdev_t *rdev;
+
+		if (s > (PAGE_SIZE>>9))
+			s = PAGE_SIZE >> 9;
+
+		do {
+			/* Note: no rcu protection needed here
+			 * as this is synchronous in the raid1d thread
+			 * which is the thread that might remove
+			 * a device.  If raid1d ever becomes multi-threaded....
+			 */
+			rdev = conf->mirrors[d].rdev;
+			if (rdev &&
+			    test_bit(In_sync, &rdev->flags) &&
+			    sync_page_io(rdev->bdev,
+					 sect + rdev->data_offset,
+					 s<<9,
+					 conf->tmppage, READ))
+				success = 1;
+			else {
+				d++;
+				if (d == conf->raid_disks)
+					d = 0;
+			}
+		} while (!success && d != read_disk);
+
+		if (!success) {
+			/* Cannot read from anywhere -- bye bye array */
+			md_error(mddev, conf->mirrors[read_disk].rdev);
+			break;
+		}
+		/* write it back and re-read */
+		start = d;
+		while (d != read_disk) {
+			if (d==0)
+				d = conf->raid_disks;
+			d--;
+			rdev = conf->mirrors[d].rdev;
+			if (rdev &&
+			    test_bit(In_sync, &rdev->flags)) {
+				if (sync_page_io(rdev->bdev,
+						 sect + rdev->data_offset,
+						 s<<9, conf->tmppage, WRITE)
+				    == 0)
+					/* Well, this device is dead */
+					md_error(mddev, rdev);
+			}
+		}
+		d = start;
+		while (d != read_disk) {
+			char b[BDEVNAME_SIZE];
+			if (d==0)
+				d = conf->raid_disks;
+			d--;
+			rdev = conf->mirrors[d].rdev;
+			if (rdev &&
+			    test_bit(In_sync, &rdev->flags)) {
+				if (sync_page_io(rdev->bdev,
+						 sect + rdev->data_offset,
+						 s<<9, conf->tmppage, READ)
+				    == 0)
+					/* Well, this device is dead */
+					md_error(mddev, rdev);
+				else {
+					atomic_add(s, &rdev->corrected_errors);
+					printk(KERN_INFO
+					       "raid1:%s: read error corrected "
+					       "(%d sectors at %llu on %s)\n",
+					       mdname(mddev), s,
+					       (unsigned long long)sect +
+					           rdev->data_offset,
+					       bdevname(rdev->bdev, b));
+				}
+			}
+		}
+		sectors -= s;
+		sect += s;
+	}
+}
+
 static void raid1d(mddev_t *mddev)
 {
 	r1bio_t *r1_bio;
@@ -1460,86 +1577,14 @@ static void raid1d(mddev_t *mddev)
 			 * This is all done synchronously while the array is
 			 * frozen
 			 */
-			sector_t sect = r1_bio->sector;
-			int sectors = r1_bio->sectors;
-			freeze_array(conf);
-			if (mddev->ro == 0) while(sectors) {
-				int s = sectors;
-				int d = r1_bio->read_disk;
-				int success = 0;
-
-				if (s > (PAGE_SIZE>>9))
-					s = PAGE_SIZE >> 9;
-
-				do {
-					/* Note: no rcu protection needed here
-					 * as this is synchronous in the raid1d thread
-					 * which is the thread that might remove
-					 * a device.  If raid1d ever becomes multi-threaded....
-					 */
-					rdev = conf->mirrors[d].rdev;
-					if (rdev &&
-					    test_bit(In_sync, &rdev->flags) &&
-					    sync_page_io(rdev->bdev,
-							 sect + rdev->data_offset,
-							 s<<9,
-							 conf->tmppage, READ))
-						success = 1;
-					else {
-						d++;
-						if (d == conf->raid_disks)
-							d = 0;
-					}
-				} while (!success && d != r1_bio->read_disk);
-
-				if (success) {
-					/* write it back and re-read */
-					int start = d;
-					while (d != r1_bio->read_disk) {
-						if (d==0)
-							d = conf->raid_disks;
-						d--;
-						rdev = conf->mirrors[d].rdev;
-						if (rdev &&
-						    test_bit(In_sync, &rdev->flags)) {
-							if (sync_page_io(rdev->bdev,
-									 sect + rdev->data_offset,
-									 s<<9, conf->tmppage, WRITE) == 0)
-								/* Well, this device is dead */
-								md_error(mddev, rdev);
-						}
-					}
-					d = start;
-					while (d != r1_bio->read_disk) {
-						if (d==0)
-							d = conf->raid_disks;
-						d--;
-						rdev = conf->mirrors[d].rdev;
-						if (rdev &&
-						    test_bit(In_sync, &rdev->flags)) {
-							if (sync_page_io(rdev->bdev,
-									 sect + rdev->data_offset,
-									 s<<9, conf->tmppage, READ) == 0)
-								/* Well, this device is dead */
-								md_error(mddev, rdev);
-							else {
-								atomic_add(s, &rdev->corrected_errors);
-								printk(KERN_INFO "raid1:%s: read error corrected (%d sectors at %llu on %s)\n",
-								       mdname(mddev), s, (unsigned long long)(sect + rdev->data_offset), bdevname(rdev->bdev, b));
-							}
-						}
-					}
-				} else {
-					/* Cannot read from anywhere -- bye bye array */
-					md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);
-					break;
-				}
-				sectors -= s;
-				sect += s;
+			if (mddev->ro == 0) {
+				freeze_array(conf);
+				fix_read_error(conf, r1_bio->read_disk,
+					       r1_bio->sector,
+					       r1_bio->sectors);
+				unfreeze_array(conf);
 			}
 
-			unfreeze_array(conf);
-
 			bio = r1_bio->bios[r1_bio->read_disk];
 			if ((disk=read_balance(conf, r1_bio)) == -1) {
 				printk(KERN_ALERT "raid1: %s: unrecoverable I/O"
@@ -1884,15 +1929,11 @@ static int run(mddev_t *mddev)
 			blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
 
 		disk->head_position = 0;
-		if (!test_bit(Faulty, &rdev->flags) && test_bit(In_sync, &rdev->flags))
-			conf->working_disks++;
 	}
 	conf->raid_disks = mddev->raid_disks;
 	conf->mddev = mddev;
 	spin_lock_init(&conf->device_lock);
 	INIT_LIST_HEAD(&conf->retry_list);
-	if (conf->working_disks == 1)
-		mddev->recovery_cp = MaxSector;
 
 	spin_lock_init(&conf->resync_lock);
 	init_waitqueue_head(&conf->wait_barrier);
@@ -1900,11 +1941,6 @@ static int run(mddev_t *mddev)
 	bio_list_init(&conf->pending_bio_list);
 	bio_list_init(&conf->flushing_bio_list);
 
-	if (!conf->working_disks) {
-		printk(KERN_ERR "raid1: no operational mirrors for %s\n",
-			mdname(mddev));
-		goto out_free_conf;
-	}
 
 	mddev->degraded = 0;
 	for (i = 0; i < conf->raid_disks; i++) {
@@ -1917,6 +1953,13 @@ static int run(mddev_t *mddev)
 			mddev->degraded++;
 		}
 	}
+	if (mddev->degraded == conf->raid_disks) {
+		printk(KERN_ERR "raid1: no operational mirrors for %s\n",
+			mdname(mddev));
+		goto out_free_conf;
+	}
+	if (conf->raid_disks - mddev->degraded == 1)
+		mddev->recovery_cp = MaxSector;
 
 	/*
 	 * find the first working one and use it as a starting point
@@ -1948,6 +1991,8 @@ static int run(mddev_t *mddev)
 
 	mddev->queue->unplug_fn = raid1_unplug;
 	mddev->queue->issue_flush_fn = raid1_issue_flush;
+	mddev->queue->backing_dev_info.congested_fn = raid1_congested;
+	mddev->queue->backing_dev_info.congested_data = mddev;
 
 	return 0;
 
@@ -2035,7 +2080,7 @@ static int raid1_reshape(mddev_t *mddev)
 	mirror_info_t *newmirrors;
 	conf_t *conf = mddev_to_conf(mddev);
 	int cnt, raid_disks;
-
+	unsigned long flags;
 	int d, d2;
 
 	/* Cannot change chunk_size, layout, or level */
@@ -2094,7 +2139,9 @@ static int raid1_reshape(mddev_t *mddev)
 	kfree(conf->poolinfo);
 	conf->poolinfo = newpoolinfo;
 
+	spin_lock_irqsave(&conf->device_lock, flags);
 	mddev->degraded += (raid_disks - conf->raid_disks);
+	spin_unlock_irqrestore(&conf->device_lock, flags);
 	conf->raid_disks = mddev->raid_disks = raid_disks;
 	mddev->delta_disks = 0;