Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4b382d06 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-linus' of git://neil.brown.name/md 

* 'for-linus' of git://neil.brown.name/md:
  md: allow resync_start to be set while an array is active.
  md/raid10:  reformat some loops with less indenting.
  md/raid10: remove unused variable.
  md/raid10: make more use of 'slot' in raid10d.
  md/raid10: some tidying up in fix_read_error
  md/raid1: improve handling of pages allocated for write-behind.
  md/raid1: try fix_sync_read_error before process_checks.
  md/raid1: tidy up new functions: process_checks and fix_sync_read_error.
  md/raid1: split out two sub-functions from sync_request_write
  md: make error_handler functions more uniform and correct.
  md/multipath: discard ->working_disks in favour of ->degraded
  md/raid1: clean up read_balance.
  md: simplify raid10 read_balance
  md/bitmap: fix saving of events_cleared and other state.
  md: reject a re-add request that cannot be honoured.
  md: Fix race when creating a new md device.
parents bdfbe804 b098636c

drivers/md/bitmap.c

+6 −4
Original line number Diff line number Diff line
@@ -493,11 +493,11 @@ void bitmap_update_sb(struct bitmap *bitmap) 
	spin_unlock_irqrestore(&bitmap->lock, flags);

	sb = kmap_atomic(bitmap->sb_page, KM_USER0);

	sb->events = cpu_to_le64(bitmap->mddev->events);

	if (bitmap->mddev->events < bitmap->events_cleared) {

	if (bitmap->mddev->events < bitmap->events_cleared)

		/* rocking back to read-only */

		bitmap->events_cleared = bitmap->mddev->events;

	sb->events_cleared = cpu_to_le64(bitmap->events_cleared);

	}

	sb->state = cpu_to_le32(bitmap->flags);

	/* Just in case these have been changed via sysfs: */

	sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ);

	sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind);
@@ -618,7 +618,7 @@ static int bitmap_read_sb(struct bitmap *bitmap) 
	if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN)

		bitmap->flags |= BITMAP_HOSTENDIAN;

	bitmap->events_cleared = le64_to_cpu(sb->events_cleared);

	if (sb->state & cpu_to_le32(BITMAP_STALE))

	if (bitmap->flags & BITMAP_STALE)

		bitmap->events_cleared = bitmap->mddev->events;

	err = 0;

out:
@@ -652,9 +652,11 @@ static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits, 
	switch (op) {

	case MASK_SET:

		sb->state |= cpu_to_le32(bits);

		bitmap->flags |= bits;

		break;

	case MASK_UNSET:

		sb->state &= cpu_to_le32(~bits);

		bitmap->flags &= ~bits;

		break;

	default:

		BUG();

drivers/md/md.c

+19 −4
Original line number Diff line number Diff line
@@ -3324,7 +3324,7 @@ resync_start_store(mddev_t *mddev, const char *buf, size_t len) 
	char *e;

	unsigned long long n = simple_strtoull(buf, &e, 10);



	if (mddev->pers)

	if (mddev->pers && !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery))

		return -EBUSY;

	if (cmd_match(buf, "none"))

		n = MaxSector;
@@ -4347,13 +4347,19 @@ static int md_alloc(dev_t dev, char *name) 
	disk->fops = &md_fops;

	disk->private_data = mddev;

	disk->queue = mddev->queue;

	blk_queue_flush(mddev->queue, REQ_FLUSH | REQ_FUA);

	/* Allow extended partitions.  This makes the

	 * 'mdp' device redundant, but we can't really

	 * remove it now.

	 */

	disk->flags |= GENHD_FL_EXT_DEVT;

	add_disk(disk);

	mddev->gendisk = disk;

	/* As soon as we call add_disk(), another thread could get

	 * through to md_open, so make sure it doesn't get too far

	 */

	mutex_lock(&mddev->open_mutex);

	add_disk(disk);



	error = kobject_init_and_add(&mddev->kobj, &md_ktype,

				     &disk_to_dev(disk)->kobj, "%s", "md");

	if (error) {
@@ -4367,8 +4373,7 @@ static int md_alloc(dev_t dev, char *name) 
	if (mddev->kobj.sd &&

	    sysfs_create_group(&mddev->kobj, &md_bitmap_group))

		printk(KERN_DEBUG "pointless warning\n");



	blk_queue_flush(mddev->queue, REQ_FLUSH | REQ_FUA);

	mutex_unlock(&mddev->open_mutex);

 abort:

	mutex_unlock(&disks_mutex);

	if (!error && mddev->kobj.sd) {
@@ -5211,6 +5216,16 @@ static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info) 
		} else

			super_types[mddev->major_version].

				validate_super(mddev, rdev);

		if ((info->state & (1<<MD_DISK_SYNC)) &&

		    (!test_bit(In_sync, &rdev->flags) ||

		     rdev->raid_disk != info->raid_disk)) {

			/* This was a hot-add request, but events doesn't

			 * match, so reject it.

			 */

			export_rdev(rdev);

			return -EINVAL;

		}



		if (test_bit(In_sync, &rdev->flags))

			rdev->saved_raid_disk = rdev->raid_disk;

		else

drivers/md/multipath.c

+32 −28
Original line number Diff line number Diff line
@@ -146,7 +146,7 @@ static void multipath_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);

	for (i = 0; i < conf->raid_disks; i++)

		seq_printf (seq, "%s",

			       conf->multipaths[i].rdev &&
@@ -186,8 +186,9 @@ static int multipath_congested(void *data, int bits) 
static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev)

{

	multipath_conf_t *conf = mddev->private;

	char b[BDEVNAME_SIZE];



	if (conf->working_disks <= 1) {

	if (conf->raid_disks - mddev->degraded <= 1) {

		/*

		 * Uh oh, we can do nothing if this is our last path, but

		 * first check if this is a queued request for a device
@@ -196,25 +197,25 @@ static void multipath_error (mddev_t *mddev, mdk_rdev_t *rdev) 
		printk(KERN_ALERT 

		       "multipath: only one IO path left and IO error.\n");

		/* leave it active... it's all we have */

	} else {

		return;

	}

	/*

	 * Mark disk as unusable

	 */

		if (!test_bit(Faulty, &rdev->flags)) {

			char b[BDEVNAME_SIZE];

			clear_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++;

		spin_unlock_irqrestore(&conf->device_lock, flags);

	}

	set_bit(Faulty, &rdev->flags);

	set_bit(MD_CHANGE_DEVS, &mddev->flags);

			conf->working_disks--;

			mddev->degraded++;

	printk(KERN_ALERT "multipath: IO failure on %s,"

	       " disabling IO path.\n"

	       "multipath: Operation continuing"

	       " on %d IO paths.\n",

	       bdevname(rdev->bdev, b),

				conf->working_disks);

		}

	}

	       conf->raid_disks - mddev->degraded);

}



static void print_multipath_conf (multipath_conf_t *conf)
@@ -227,7 +228,7 @@ static void print_multipath_conf (multipath_conf_t *conf) 
		printk("(conf==NULL)\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);



	for (i = 0; i < conf->raid_disks; i++) {
@@ -274,10 +275,11 @@ static int multipath_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) 
							   PAGE_CACHE_SIZE - 1);

			}



			conf->working_disks++;

			spin_lock_irq(&conf->device_lock);

			mddev->degraded--;

			rdev->raid_disk = path;

			set_bit(In_sync, &rdev->flags);

			spin_unlock_irq(&conf->device_lock);

			rcu_assign_pointer(p->rdev, rdev);

			err = 0;

			md_integrity_add_rdev(rdev, mddev);
@@ -391,6 +393,7 @@ static int multipath_run (mddev_t *mddev) 
	int disk_idx;

	struct multipath_info *disk;

	mdk_rdev_t *rdev;

	int working_disks;



	if (md_check_no_bitmap(mddev))

		return -EINVAL;
@@ -424,7 +427,7 @@ static int multipath_run (mddev_t *mddev) 
		goto out_free_conf;

	}



	conf->working_disks = 0;

	working_disks = 0;

	list_for_each_entry(rdev, &mddev->disks, same_set) {

		disk_idx = rdev->raid_disk;

		if (disk_idx < 0 ||
@@ -446,7 +449,7 @@ static int multipath_run (mddev_t *mddev) 
		}



		if (!test_bit(Faulty, &rdev->flags))

			conf->working_disks++;

			working_disks++;

	}



	conf->raid_disks = mddev->raid_disks;
@@ -454,12 +457,12 @@ static int multipath_run (mddev_t *mddev) 
	spin_lock_init(&conf->device_lock);

	INIT_LIST_HEAD(&conf->retry_list);



	if (!conf->working_disks) {

	if (!working_disks) {

		printk(KERN_ERR "multipath: no operational IO paths for %s\n",

			mdname(mddev));

		goto out_free_conf;

	}

	mddev->degraded = conf->raid_disks - conf->working_disks;

	mddev->degraded = conf->raid_disks - working_disks;



	conf->pool = mempool_create_kmalloc_pool(NR_RESERVED_BUFS,

						 sizeof(struct multipath_bh));
@@ -481,7 +484,8 @@ static int multipath_run (mddev_t *mddev) 


	printk(KERN_INFO 

		"multipath: array %s active with %d out of %d IO paths\n",

		mdname(mddev), conf->working_disks, mddev->raid_disks);

		mdname(mddev), conf->raid_disks - mddev->degraded,

	       mddev->raid_disks);

	/*

	 * Ok, everything is just fine now

	 */

drivers/md/multipath.h

+0 −1
Original line number Diff line number Diff line
@@ -9,7 +9,6 @@ struct multipath_private_data { 
	mddev_t			*mddev;

	struct multipath_info	*multipaths;

	int			raid_disks;

	int			working_disks;

	spinlock_t		device_lock;

	struct list_head	retry_list;

drivers/md/raid1.c

+252 −254
Original line number Diff line number Diff line
@@ -297,23 +297,24 @@ static void raid1_end_read_request(struct bio *bio, int error) 
	rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev);

}



static void r1_bio_write_done(r1bio_t *r1_bio, int vcnt, struct bio_vec *bv,

			      int behind)

static void r1_bio_write_done(r1bio_t *r1_bio)

{

	if (atomic_dec_and_test(&r1_bio->remaining))

	{

		/* it really is the end of this request */

		if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {

			/* free extra copy of the data pages */

			int i = vcnt;

			int i = r1_bio->behind_page_count;

			while (i--)

				safe_put_page(bv[i].bv_page);

				safe_put_page(r1_bio->behind_pages[i]);

			kfree(r1_bio->behind_pages);

			r1_bio->behind_pages = NULL;

		}

		/* clear the bitmap if all writes complete successfully */

		bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,

				r1_bio->sectors,

				!test_bit(R1BIO_Degraded, &r1_bio->state),

				behind);

				test_bit(R1BIO_BehindIO, &r1_bio->state));

		md_write_end(r1_bio->mddev);

		raid_end_bio_io(r1_bio);

	}
@@ -386,7 +387,7 @@ static void raid1_end_write_request(struct bio *bio, int error) 
	 * Let's see if all mirrored write operations have finished

	 * already.

	 */

	r1_bio_write_done(r1_bio, bio->bi_vcnt, bio->bi_io_vec, behind);

	r1_bio_write_done(r1_bio);



	if (to_put)

		bio_put(to_put);
@@ -411,10 +412,10 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) 
{

	const sector_t this_sector = r1_bio->sector;

	const int sectors = r1_bio->sectors;

	int new_disk = -1;

	int start_disk;

	int best_disk;

	int i;

	sector_t new_distance, current_distance;

	sector_t best_dist;

	mdk_rdev_t *rdev;

	int choose_first;
@@ -425,6 +426,8 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) 
	 * We take the first readable disk when above the resync window.

	 */

 retry:

	best_disk = -1;

	best_dist = MaxSector;

	if (conf->mddev->recovery_cp < MaxSector &&

	    (this_sector + sectors >= conf->next_resync)) {

		choose_first = 1;
@@ -434,8 +437,8 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) 
		start_disk = conf->last_used;

	}



	/* make sure the disk is operational */

	for (i = 0 ; i < conf->raid_disks ; i++) {

		sector_t dist;

		int disk = start_disk + i;

		if (disk >= conf->raid_disks)

			disk -= conf->raid_disks;
@@ -443,60 +446,43 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) 
		rdev = rcu_dereference(conf->mirrors[disk].rdev);

		if (r1_bio->bios[disk] == IO_BLOCKED

		    || rdev == NULL

		    || !test_bit(In_sync, &rdev->flags))

		    || test_bit(Faulty, &rdev->flags))

			continue;

		if (!test_bit(In_sync, &rdev->flags) &&

		    rdev->recovery_offset < this_sector + sectors)

			continue;

		if (test_bit(WriteMostly, &rdev->flags)) {

			/* Don't balance among write-mostly, just

			 * use the first as a last resort */

			if (best_disk < 0)

				best_disk = disk;

			continue;



		new_disk = disk;

		if (!test_bit(WriteMostly, &rdev->flags))

			break;

		}



	if (new_disk < 0 || choose_first)

		goto rb_out;



	/*

	 * Don't change to another disk for sequential reads:

		/* This is a reasonable device to use.  It might

		 * even be best.

		 */

	if (conf->next_seq_sect == this_sector)

		goto rb_out;

	if (this_sector == conf->mirrors[new_disk].head_position)

		goto rb_out;



	current_distance = abs(this_sector 

			       - conf->mirrors[new_disk].head_position);



	/* look for a better disk - i.e. head is closer */

	start_disk = new_disk;

	for (i = 1; i < conf->raid_disks; i++) {

		int disk = start_disk + 1;

		if (disk >= conf->raid_disks)

			disk -= conf->raid_disks;



		rdev = rcu_dereference(conf->mirrors[disk].rdev);

		if (r1_bio->bios[disk] == IO_BLOCKED

		    || rdev == NULL

		    || !test_bit(In_sync, &rdev->flags)

		    || test_bit(WriteMostly, &rdev->flags))

			continue;



		if (!atomic_read(&rdev->nr_pending)) {

			new_disk = disk;

		dist = abs(this_sector - conf->mirrors[disk].head_position);

		if (choose_first

		    /* Don't change to another disk for sequential reads */

		    || conf->next_seq_sect == this_sector

		    || dist == 0

		    /* If device is idle, use it */

		    || atomic_read(&rdev->nr_pending) == 0) {

			best_disk = disk;

			break;

		}

		new_distance = abs(this_sector - conf->mirrors[disk].head_position);

		if (new_distance < current_distance) {

			current_distance = new_distance;

			new_disk = disk;

		if (dist < best_dist) {

			best_dist = dist;

			best_disk = disk;

		}

	}



 rb_out:

	if (new_disk >= 0) {

		rdev = rcu_dereference(conf->mirrors[new_disk].rdev);

	if (best_disk >= 0) {

		rdev = rcu_dereference(conf->mirrors[best_disk].rdev);

		if (!rdev)

			goto retry;

		atomic_inc(&rdev->nr_pending);

		if (!test_bit(In_sync, &rdev->flags)) {

		if (test_bit(Faulty, &rdev->flags)) {

			/* cannot risk returning a device that failed

			 * before we inc'ed nr_pending

			 */
@@ -504,11 +490,11 @@ static int read_balance(conf_t *conf, r1bio_t *r1_bio) 
			goto retry;

		}

		conf->next_seq_sect = this_sector + sectors;

		conf->last_used = new_disk;

		conf->last_used = best_disk;

	}

	rcu_read_unlock();



	return new_disk;

	return best_disk;

}



static int raid1_congested(void *data, int bits)
@@ -675,37 +661,36 @@ static void unfreeze_array(conf_t *conf) 




/* duplicate the data pages for behind I/O 

 * We return a list of bio_vec rather than just page pointers

 * as it makes freeing easier

 */

static struct bio_vec *alloc_behind_pages(struct bio *bio)

static void alloc_behind_pages(struct bio *bio, r1bio_t *r1_bio)

{

	int i;

	struct bio_vec *bvec;

	struct bio_vec *pages = kzalloc(bio->bi_vcnt * sizeof(struct bio_vec),

	struct page **pages = kzalloc(bio->bi_vcnt * sizeof(struct page*),

					GFP_NOIO);

	if (unlikely(!pages))

		goto do_sync_io;

		return;



	bio_for_each_segment(bvec, bio, i) {

		pages[i].bv_page = alloc_page(GFP_NOIO);

		if (unlikely(!pages[i].bv_page))

		pages[i] = alloc_page(GFP_NOIO);

		if (unlikely(!pages[i]))

			goto do_sync_io;

		memcpy(kmap(pages[i].bv_page) + bvec->bv_offset,

		memcpy(kmap(pages[i]) + bvec->bv_offset,

			kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len);

		kunmap(pages[i].bv_page);

		kunmap(pages[i]);

		kunmap(bvec->bv_page);

	}



	return pages;

	r1_bio->behind_pages = pages;

	r1_bio->behind_page_count = bio->bi_vcnt;

	set_bit(R1BIO_BehindIO, &r1_bio->state);

	return;



do_sync_io:

	if (pages)

		for (i = 0; i < bio->bi_vcnt && pages[i].bv_page; i++)

			put_page(pages[i].bv_page);

	for (i = 0; i < bio->bi_vcnt; i++)

		if (pages[i])

			put_page(pages[i]);

	kfree(pages);

	PRINTK("%dB behind alloc failed, doing sync I/O\n", bio->bi_size);

	return NULL;

}



static int make_request(mddev_t *mddev, struct bio * bio)
@@ -717,7 +702,6 @@ static int make_request(mddev_t *mddev, struct bio * bio) 
	int i, targets = 0, disks;

	struct bitmap *bitmap;

	unsigned long flags;

	struct bio_vec *behind_pages = NULL;

	const int rw = bio_data_dir(bio);

	const unsigned long do_sync = (bio->bi_rw & REQ_SYNC);

	const unsigned long do_flush_fua = (bio->bi_rw & (REQ_FLUSH | REQ_FUA));
@@ -870,9 +854,8 @@ static int make_request(mddev_t *mddev, struct bio * bio) 
	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);

	    !waitqueue_active(&bitmap->behind_wait))

		alloc_behind_pages(bio, r1_bio);



	atomic_set(&r1_bio->remaining, 1);

	atomic_set(&r1_bio->behind_remaining, 0);
@@ -893,7 +876,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) 
		mbio->bi_rw = WRITE | do_flush_fua | do_sync;

		mbio->bi_private = r1_bio;



		if (behind_pages) {

		if (r1_bio->behind_pages) {

			struct bio_vec *bvec;

			int j;
@@ -905,7 +888,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) 
			 * them all

			 */

			__bio_for_each_segment(bvec, mbio, j, 0)

				bvec->bv_page = behind_pages[j].bv_page;

				bvec->bv_page = r1_bio->behind_pages[j];

			if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags))

				atomic_inc(&r1_bio->behind_remaining);

		}
@@ -915,8 +898,7 @@ static int make_request(mddev_t *mddev, struct bio * bio) 
		bio_list_add(&conf->pending_bio_list, mbio);

		spin_unlock_irqrestore(&conf->device_lock, flags);

	}

	r1_bio_write_done(r1_bio, bio->bi_vcnt, behind_pages, behind_pages != NULL);

	kfree(behind_pages); /* the behind pages are attached to the bios now */

	r1_bio_write_done(r1_bio);



	/* In case raid1d snuck in to freeze_array */

	wake_up(&conf->wait_barrier);
@@ -1196,101 +1178,9 @@ static void end_sync_write(struct bio *bio, int error) 
	}

}



static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)

static int fix_sync_read_error(r1bio_t *r1_bio)

{

	conf_t *conf = mddev->private;

	int i;

	int disks = conf->raid_disks;

	struct bio *bio, *wbio;



	bio = r1_bio->bios[r1_bio->read_disk];





	if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {

		/* We have read all readable devices.  If we haven't

		 * got the block, then there is no hope left.

		 * If we have, then we want to do a comparison

		 * and skip the write if everything is the same.

		 * If any blocks failed to read, then we need to

		 * attempt an over-write

		 */

		int primary;

		if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {

			for (i=0; i<mddev->raid_disks; i++)

				if (r1_bio->bios[i]->bi_end_io == end_sync_read)

					md_error(mddev, conf->mirrors[i].rdev);



			md_done_sync(mddev, r1_bio->sectors, 1);

			put_buf(r1_bio);

			return;

		}

		for (primary=0; primary<mddev->raid_disks; primary++)

			if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&

			    test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) {

				r1_bio->bios[primary]->bi_end_io = NULL;

				rdev_dec_pending(conf->mirrors[primary].rdev, mddev);

				break;

			}

		r1_bio->read_disk = primary;

		for (i=0; i<mddev->raid_disks; i++)

			if (r1_bio->bios[i]->bi_end_io == end_sync_read) {

				int j;

				int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);

				struct bio *pbio = r1_bio->bios[primary];

				struct bio *sbio = r1_bio->bios[i];



				if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) {

					for (j = vcnt; j-- ; ) {

						struct page *p, *s;

						p = pbio->bi_io_vec[j].bv_page;

						s = sbio->bi_io_vec[j].bv_page;

						if (memcmp(page_address(p),

							   page_address(s),

							   PAGE_SIZE))

							break;

					}

				} else

					j = 0;

				if (j >= 0)

					mddev->resync_mismatches += r1_bio->sectors;

				if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)

					      && test_bit(BIO_UPTODATE, &sbio->bi_flags))) {

					sbio->bi_end_io = NULL;

					rdev_dec_pending(conf->mirrors[i].rdev, mddev);

				} else {

					/* fixup the bio for reuse */

					int size;

					sbio->bi_vcnt = vcnt;

					sbio->bi_size = r1_bio->sectors << 9;

					sbio->bi_idx = 0;

					sbio->bi_phys_segments = 0;

					sbio->bi_flags &= ~(BIO_POOL_MASK - 1);

					sbio->bi_flags |= 1 << BIO_UPTODATE;

					sbio->bi_next = NULL;

					sbio->bi_sector = r1_bio->sector +

						conf->mirrors[i].rdev->data_offset;

					sbio->bi_bdev = conf->mirrors[i].rdev->bdev;

					size = sbio->bi_size;

					for (j = 0; j < vcnt ; j++) {

						struct bio_vec *bi;

						bi = &sbio->bi_io_vec[j];

						bi->bv_offset = 0;

						if (size > PAGE_SIZE)

							bi->bv_len = PAGE_SIZE;

						else

							bi->bv_len = size;

						size -= PAGE_SIZE;

						memcpy(page_address(bi->bv_page),

						       page_address(pbio->bi_io_vec[j].bv_page),

						       PAGE_SIZE);

					}



				}

			}

	}

	if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {

		/* ouch - failed to read all of that.

		 * Try some synchronous reads of other devices to get

	/* Try some synchronous reads of other devices to get

	 * good data, much like with normal read errors.  Only

	 * read into the pages we already have so we don't

	 * need to re-issue the read request.
@@ -1298,6 +1188,9 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) 
	 * active sync request, there is no normal IO, and

	 * no overlapping syncs.

	 */

	mddev_t *mddev = r1_bio->mddev;

	conf_t *conf = mddev->private;

	struct bio *bio = r1_bio->bios[r1_bio->read_disk];

	sector_t sect = r1_bio->sector;

	int sectors = r1_bio->sectors;

	int idx = 0;
@@ -1307,6 +1200,7 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) 
		int d = r1_bio->read_disk;

		int success = 0;

		mdk_rdev_t *rdev;

		int start;



		if (s > (PAGE_SIZE>>9))

			s = PAGE_SIZE >> 9;
@@ -1331,10 +1225,22 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) 
				d = 0;

		} while (!success && d != r1_bio->read_disk);



			if (success) {

				int start = d;

		if (!success) {

			char b[BDEVNAME_SIZE];

			/* Cannot read from anywhere, array is toast */

			md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);

			printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O read error"

			       " for block %llu\n",

			       mdname(mddev),

			       bdevname(bio->bi_bdev, b),

			       (unsigned long long)r1_bio->sector);

			md_done_sync(mddev, r1_bio->sectors, 0);

			put_buf(r1_bio);

			return 0;

		}



		start = d;

		/* write it back and re-read */

				set_bit(R1BIO_Uptodate, &r1_bio->state);

		while (d != r1_bio->read_disk) {

			if (d == 0)

				d = conf->raid_disks;
@@ -1342,13 +1248,16 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) 
			if (r1_bio->bios[d]->bi_end_io != end_sync_read)

				continue;

			rdev = conf->mirrors[d].rdev;

					atomic_add(s, &rdev->corrected_errors);

			if (sync_page_io(rdev,

					 sect,

					 s<<9,

					 bio->bi_io_vec[idx].bv_page,

							 WRITE, false) == 0)

					 WRITE, false) == 0) {

				r1_bio->bios[d]->bi_end_io = NULL;

				rdev_dec_pending(rdev, mddev);

				md_error(mddev, rdev);

			} else

				atomic_add(s, &rdev->corrected_errors);

		}

		d = start;

		while (d != r1_bio->read_disk) {
@@ -1365,25 +1274,114 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) 
					 READ, false) == 0)

				md_error(mddev, rdev);

		}

			} else {

				char b[BDEVNAME_SIZE];

				/* Cannot read from anywhere, array is toast */

				md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev);

				printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O read error"

				       " for block %llu\n",

				       mdname(mddev),

				       bdevname(bio->bi_bdev, b),

				       (unsigned long long)r1_bio->sector);

				md_done_sync(mddev, r1_bio->sectors, 0);

				put_buf(r1_bio);

				return;

			}

		sectors -= s;

		sect += s;

		idx ++;

	}

	set_bit(R1BIO_Uptodate, &r1_bio->state);

	set_bit(BIO_UPTODATE, &bio->bi_flags);

	return 1;

}



static int process_checks(r1bio_t *r1_bio)

{

	/* We have read all readable devices.  If we haven't

	 * got the block, then there is no hope left.

	 * If we have, then we want to do a comparison

	 * and skip the write if everything is the same.

	 * If any blocks failed to read, then we need to

	 * attempt an over-write

	 */

	mddev_t *mddev = r1_bio->mddev;

	conf_t *conf = mddev->private;

	int primary;

	int i;



	for (primary = 0; primary < conf->raid_disks; primary++)

		if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&

		    test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) {

			r1_bio->bios[primary]->bi_end_io = NULL;

			rdev_dec_pending(conf->mirrors[primary].rdev, mddev);

			break;

		}

	r1_bio->read_disk = primary;

	for (i = 0; i < conf->raid_disks; i++) {

		int j;

		int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);

		struct bio *pbio = r1_bio->bios[primary];

		struct bio *sbio = r1_bio->bios[i];

		int size;



		if (r1_bio->bios[i]->bi_end_io != end_sync_read)

			continue;



		if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) {

			for (j = vcnt; j-- ; ) {

				struct page *p, *s;

				p = pbio->bi_io_vec[j].bv_page;

				s = sbio->bi_io_vec[j].bv_page;

				if (memcmp(page_address(p),

					   page_address(s),

					   PAGE_SIZE))

					break;

			}

		} else

			j = 0;

		if (j >= 0)

			mddev->resync_mismatches += r1_bio->sectors;

		if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)

			      && test_bit(BIO_UPTODATE, &sbio->bi_flags))) {

			/* No need to write to this device. */

			sbio->bi_end_io = NULL;

			rdev_dec_pending(conf->mirrors[i].rdev, mddev);

			continue;

		}

		/* fixup the bio for reuse */

		sbio->bi_vcnt = vcnt;

		sbio->bi_size = r1_bio->sectors << 9;

		sbio->bi_idx = 0;

		sbio->bi_phys_segments = 0;

		sbio->bi_flags &= ~(BIO_POOL_MASK - 1);

		sbio->bi_flags |= 1 << BIO_UPTODATE;

		sbio->bi_next = NULL;

		sbio->bi_sector = r1_bio->sector +

			conf->mirrors[i].rdev->data_offset;

		sbio->bi_bdev = conf->mirrors[i].rdev->bdev;

		size = sbio->bi_size;

		for (j = 0; j < vcnt ; j++) {

			struct bio_vec *bi;

			bi = &sbio->bi_io_vec[j];

			bi->bv_offset = 0;

			if (size > PAGE_SIZE)

				bi->bv_len = PAGE_SIZE;

			else

				bi->bv_len = size;

			size -= PAGE_SIZE;

			memcpy(page_address(bi->bv_page),

			       page_address(pbio->bi_io_vec[j].bv_page),

			       PAGE_SIZE);

		}

	}

	return 0;

}



static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)

{

	conf_t *conf = mddev->private;

	int i;

	int disks = conf->raid_disks;

	struct bio *bio, *wbio;



	bio = r1_bio->bios[r1_bio->read_disk];



	if (!test_bit(R1BIO_Uptodate, &r1_bio->state))

		/* ouch - failed to read all of that. */

		if (!fix_sync_read_error(r1_bio))

			return;



	if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))

		if (process_checks(r1_bio) < 0)

			return;

	/*

	 * schedule writes

	 */
@@ -2063,7 +2061,7 @@ static int raid1_resize(mddev_t *mddev, sector_t sectors) 
	set_capacity(mddev->gendisk, mddev->array_sectors);

	revalidate_disk(mddev->gendisk);

	if (sectors > mddev->dev_sectors &&

	    mddev->recovery_cp == MaxSector) {

	    mddev->recovery_cp > mddev->dev_sectors) {

		mddev->recovery_cp = mddev->dev_sectors;

		set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

	}