1 files changed, 128 insertions, 28 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index a8bc93d6ff63..7fbb60883280 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -106,15 +106,30 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
 	}
 	/*
 	 * Allocate RESYNC_PAGES data pages and attach them to
-	 * the first bio;
+	 * the first bio.
+	 * If this is a user-requested check/repair, allocate
+	 * RESYNC_PAGES for each bio.
 	 */
-	bio = r1_bio->bios[0];
-	for (i = 0; i < RESYNC_PAGES; i++) {
-		page = alloc_page(gfp_flags);
-		if (unlikely(!page))
-			goto out_free_pages;
-
-		bio->bi_io_vec[i].bv_page = page;
+	if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
+		j = pi->raid_disks;
+	else
+		j = 1;
+	while(j--) {
+		bio = r1_bio->bios[j];
+		for (i = 0; i < RESYNC_PAGES; i++) {
+			page = alloc_page(gfp_flags);
+			if (unlikely(!page))
+				goto out_free_pages;
+
+			bio->bi_io_vec[i].bv_page = page;
+		}
+	}
+	/* If not user-requests, copy the page pointers to all bios */
+	if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) {
+		for (i=0; i<RESYNC_PAGES ; i++)
+			for (j=1; j<pi->raid_disks; j++)
+				r1_bio->bios[j]->bi_io_vec[i].bv_page =
+					r1_bio->bios[0]->bi_io_vec[i].bv_page;
 	}
 
 	r1_bio->master_bio = NULL;
@@ -122,8 +137,10 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
 	return r1_bio;
 
 out_free_pages:
-	for ( ; i > 0 ; i--)
-		__free_page(bio->bi_io_vec[i-1].bv_page);
+	for (i=0; i < RESYNC_PAGES ; i++)
+		for (j=0 ; j < pi->raid_disks; j++)
+			__free_page(r1_bio->bios[j]->bi_io_vec[i].bv_page);
+	j = -1;
 out_free_bio:
 	while ( ++j < pi->raid_disks )
 		bio_put(r1_bio->bios[j]);
@@ -134,14 +151,16 @@ out_free_bio:
 static void r1buf_pool_free(void *__r1_bio, void *data)
 {
 	struct pool_info *pi = data;
-	int i;
+	int i,j;
 	r1bio_t *r1bio = __r1_bio;
-	struct bio *bio = r1bio->bios[0];
 
-	for (i = 0; i < RESYNC_PAGES; i++) {
-		__free_page(bio->bi_io_vec[i].bv_page);
-		bio->bi_io_vec[i].bv_page = NULL;
-	}
+	for (i = 0; i < RESYNC_PAGES; i++)
+		for (j = pi->raid_disks; j-- ;) {
+			if (j == 0 ||
+			    r1bio->bios[j]->bi_io_vec[i].bv_page !=
+			    r1bio->bios[0]->bi_io_vec[i].bv_page)
+				__free_page(r1bio->bios[j]->bi_io_vec[i].bv_page);
+		}
 	for (i=0 ; i < pi->raid_disks; i++)
 		bio_put(r1bio->bios[i]);
 
@@ -1077,13 +1096,16 @@ abort:
 static int end_sync_read(struct bio *bio, unsigned int bytes_done, int error)
 {
 	r1bio_t * r1_bio = (r1bio_t *)(bio->bi_private);
+	int i;
 
 	if (bio->bi_size)
 		return 1;
 
-	if (r1_bio->bios[r1_bio->read_disk] != bio)
-		BUG();
-	update_head_pos(r1_bio->read_disk, r1_bio);
+	for (i=r1_bio->mddev->raid_disks; i--; )
+		if (r1_bio->bios[i] == bio)
+			break;
+	BUG_ON(i < 0);
+	update_head_pos(i, r1_bio);
 	/*
 	 * we have read a block, now it needs to be re-written,
 	 * or re-read if the read failed.
@@ -1091,7 +1113,9 @@ static int end_sync_read(struct bio *bio, unsigned int bytes_done, int error)
 	 */
 	if (test_bit(BIO_UPTODATE, &bio->bi_flags))
 		set_bit(R1BIO_Uptodate, &r1_bio->state);
-	reschedule_retry(r1_bio);
+
+	if (atomic_dec_and_test(&r1_bio->remaining))
+		reschedule_retry(r1_bio);
 	return 0;
 }
 
@@ -1134,9 +1158,65 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)
 	bio = r1_bio->bios[r1_bio->read_disk];
 
 
-	/*
-	 * schedule writes
-	 */
+	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;
+				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 &&
+			    test_bit(BIO_UPTODATE, &r1_bio->bios[i]->bi_flags)) {
+				int j;
+				int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);
+				struct bio *pbio = r1_bio->bios[primary];
+				struct bio *sbio = r1_bio->bios[i];
+				for (j = vcnt; j-- ; )
+					if (memcmp(page_address(pbio->bi_io_vec[j].bv_page),
+						   page_address(sbio->bi_io_vec[j].bv_page),
+						   PAGE_SIZE))
+						break;
+				if (j >= 0)
+					mddev->resync_mismatches += r1_bio->sectors;
+				if (j < 0 || test_bit(MD_RECOVERY_CHECK, &mddev->recovery))
+					sbio->bi_end_io = NULL;
+				else {
+					/* 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_hw_segments = 0;
+					sbio->bi_hw_front_size = 0;
+					sbio->bi_hw_back_size = 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;
+				}
+			}
+	}
 	if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
 		/* ouch - failed to read all of that.
 		 * Try some synchronous reads of other devices to get
@@ -1216,6 +1296,10 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)
 			idx ++;
 		}
 	}
+
+	/*
+	 * schedule writes
+	 */
 	atomic_set(&r1_bio->remaining, 1);
 	for (i = 0; i < disks ; i++) {
 		wbio = r1_bio->bios[i];
@@ -1618,10 +1702,10 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
 		for (i=0 ; i < conf->raid_disks; i++) {
 			bio = r1_bio->bios[i];
 			if (bio->bi_end_io) {
-				page = r1_bio->bios[0]->bi_io_vec[bio->bi_vcnt].bv_page;
+				page = bio->bi_io_vec[bio->bi_vcnt].bv_page;
 				if (bio_add_page(bio, page, len, 0) == 0) {
 					/* stop here */
-					r1_bio->bios[0]->bi_io_vec[bio->bi_vcnt].bv_page = page;
+					bio->bi_io_vec[bio->bi_vcnt].bv_page = page;
 					while (i > 0) {
 						i--;
 						bio = r1_bio->bios[i];
@@ -1641,12 +1725,28 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i
 		sync_blocks -= (len>>9);
 	} while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES);
  bio_full:
-	bio = r1_bio->bios[r1_bio->read_disk];
 	r1_bio->sectors = nr_sectors;
 
-	md_sync_acct(conf->mirrors[r1_bio->read_disk].rdev->bdev, nr_sectors);
+	/* For a user-requested sync, we read all readable devices and do a
+	 * compare
+	 */
+	if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
+		atomic_set(&r1_bio->remaining, read_targets);
+		for (i=0; i<conf->raid_disks; i++) {
+			bio = r1_bio->bios[i];
+			if (bio->bi_end_io == end_sync_read) {
+				md_sync_acct(conf->mirrors[i].rdev->bdev, nr_sectors);
+				generic_make_request(bio);
+			}
+		}
+	} else {
+		atomic_set(&r1_bio->remaining, 1);
+		bio = r1_bio->bios[r1_bio->read_disk];
+		md_sync_acct(conf->mirrors[r1_bio->read_disk].rdev->bdev,
+			     nr_sectors);
+		generic_make_request(bio);
 
-	generic_make_request(bio);
+	}
 
 	return nr_sectors;
 }