1 files changed, 142 insertions, 100 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 50c5a8762aed..cd4d1315aaa9 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1310,6 +1310,8 @@ again:
 	if (ret) {
 		btrfs_error(root->fs_info, ret,
 			    "Failed to remove dev extent item");
+	} else {
+		trans->transaction->have_free_bgs = 1;
 	}
 out:
 	btrfs_free_path(path);
@@ -4196,7 +4198,7 @@ static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
 
 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
 {
-	if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)))
+	if (!(type & BTRFS_BLOCK_GROUP_RAID56_MASK))
 		return;
 
 	btrfs_set_fs_incompat(info, RAID56);
@@ -4803,10 +4805,8 @@ unsigned long btrfs_full_stripe_len(struct btrfs_root *root,
 
 	BUG_ON(em->start > logical || em->start + em->len < logical);
 	map = (struct map_lookup *)em->bdev;
-	if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-			 BTRFS_BLOCK_GROUP_RAID6)) {
+	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
 		len = map->stripe_len * nr_data_stripes(map);
-	}
 	free_extent_map(em);
 	return len;
 }
@@ -4826,8 +4826,7 @@ int btrfs_is_parity_mirror(struct btrfs_mapping_tree *map_tree,
 
 	BUG_ON(em->start > logical || em->start + em->len < logical);
 	map = (struct map_lookup *)em->bdev;
-	if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-			 BTRFS_BLOCK_GROUP_RAID6))
+	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
 		ret = 1;
 	free_extent_map(em);
 	return ret;
@@ -4876,32 +4875,24 @@ static inline int parity_smaller(u64 a, u64 b)
 }
 
 /* Bubble-sort the stripe set to put the parity/syndrome stripes last */
-static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map)
+static void sort_parity_stripes(struct btrfs_bio *bbio, int num_stripes)
 {
 	struct btrfs_bio_stripe s;
-	int real_stripes = bbio->num_stripes - bbio->num_tgtdevs;
 	int i;
 	u64 l;
 	int again = 1;
-	int m;
 
 	while (again) {
 		again = 0;
-		for (i = 0; i < real_stripes - 1; i++) {
-			if (parity_smaller(raid_map[i], raid_map[i+1])) {
+		for (i = 0; i < num_stripes - 1; i++) {
+			if (parity_smaller(bbio->raid_map[i],
+					   bbio->raid_map[i+1])) {
 				s = bbio->stripes[i];
-				l = raid_map[i];
+				l = bbio->raid_map[i];
 				bbio->stripes[i] = bbio->stripes[i+1];
-				raid_map[i] = raid_map[i+1];
+				bbio->raid_map[i] = bbio->raid_map[i+1];
 				bbio->stripes[i+1] = s;
-				raid_map[i+1] = l;
-
-				if (bbio->tgtdev_map) {
-					m = bbio->tgtdev_map[i];
-					bbio->tgtdev_map[i] =
-							bbio->tgtdev_map[i + 1];
-					bbio->tgtdev_map[i + 1] = m;
-				}
+				bbio->raid_map[i+1] = l;
 
 				again = 1;
 			}
@@ -4909,10 +4900,41 @@ static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map)
 	}
 }
 
+static struct btrfs_bio *alloc_btrfs_bio(int total_stripes, int real_stripes)
+{
+	struct btrfs_bio *bbio = kzalloc(
+		sizeof(struct btrfs_bio) +
+		sizeof(struct btrfs_bio_stripe) * (total_stripes) +
+		sizeof(int) * (real_stripes) +
+		sizeof(u64) * (real_stripes),
+		GFP_NOFS);
+	if (!bbio)
+		return NULL;
+
+	atomic_set(&bbio->error, 0);
+	atomic_set(&bbio->refs, 1);
+
+	return bbio;
+}
+
+void btrfs_get_bbio(struct btrfs_bio *bbio)
+{
+	WARN_ON(!atomic_read(&bbio->refs));
+	atomic_inc(&bbio->refs);
+}
+
+void btrfs_put_bbio(struct btrfs_bio *bbio)
+{
+	if (!bbio)
+		return;
+	if (atomic_dec_and_test(&bbio->refs))
+		kfree(bbio);
+}
+
 static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 			     u64 logical, u64 *length,
 			     struct btrfs_bio **bbio_ret,
-			     int mirror_num, u64 **raid_map_ret)
+			     int mirror_num, int need_raid_map)
 {
 	struct extent_map *em;
 	struct map_lookup *map;
@@ -4925,7 +4947,6 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 	u64 stripe_nr_orig;
 	u64 stripe_nr_end;
 	u64 stripe_len;
-	u64 *raid_map = NULL;
 	int stripe_index;
 	int i;
 	int ret = 0;
@@ -4976,7 +4997,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 	stripe_offset = offset - stripe_offset;
 
 	/* if we're here for raid56, we need to know the stripe aligned start */
-	if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) {
+	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 		unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);
 		raid56_full_stripe_start = offset;
 
@@ -4989,8 +5010,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 
 	if (rw & REQ_DISCARD) {
 		/* we don't discard raid56 yet */
-		if (map->type &
-		    (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)) {
+		if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 			ret = -EOPNOTSUPP;
 			goto out;
 		}
@@ -5000,7 +5020,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		/* For writes to RAID[56], allow a full stripeset across all disks.
 		   For other RAID types and for RAID[56] reads, just allow a single
 		   stripe (on a single disk). */
-		if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6) &&
+		if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&
 		    (rw & REQ_WRITE)) {
 			max_len = stripe_len * nr_data_stripes(map) -
 				(offset - raid56_full_stripe_start);
@@ -5047,7 +5067,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		u64 physical_of_found = 0;
 
 		ret = __btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS,
-			     logical, &tmp_length, &tmp_bbio, 0, NULL);
+			     logical, &tmp_length, &tmp_bbio, 0, 0);
 		if (ret) {
 			WARN_ON(tmp_bbio != NULL);
 			goto out;
@@ -5061,7 +5081,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 			 * is not left of the left cursor
 			 */
 			ret = -EIO;
-			kfree(tmp_bbio);
+			btrfs_put_bbio(tmp_bbio);
 			goto out;
 		}
 
@@ -5096,11 +5116,11 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		} else {
 			WARN_ON(1);
 			ret = -EIO;
-			kfree(tmp_bbio);
+			btrfs_put_bbio(tmp_bbio);
 			goto out;
 		}
 
-		kfree(tmp_bbio);
+		btrfs_put_bbio(tmp_bbio);
 	} else if (mirror_num > map->num_stripes) {
 		mirror_num = 0;
 	}
@@ -5166,15 +5186,10 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 			mirror_num = stripe_index - old_stripe_index + 1;
 		}
 
-	} else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-				BTRFS_BLOCK_GROUP_RAID6)) {
-		u64 tmp;
-
-		if (raid_map_ret &&
+	} else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+		if (need_raid_map &&
 		    ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
 		     mirror_num > 1)) {
-			int i, rot;
-
 			/* push stripe_nr back to the start of the full stripe */
 			stripe_nr = raid56_full_stripe_start;
 			do_div(stripe_nr, stripe_len * nr_data_stripes(map));
@@ -5183,32 +5198,12 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 			num_stripes = map->num_stripes;
 			max_errors = nr_parity_stripes(map);
 
-			raid_map = kmalloc_array(num_stripes, sizeof(u64),
-					   GFP_NOFS);
-			if (!raid_map) {
-				ret = -ENOMEM;
-				goto out;
-			}
-
-			/* Work out the disk rotation on this stripe-set */
-			tmp = stripe_nr;
-			rot = do_div(tmp, num_stripes);
-
-			/* Fill in the logical address of each stripe */
-			tmp = stripe_nr * nr_data_stripes(map);
-			for (i = 0; i < nr_data_stripes(map); i++)
-				raid_map[(i+rot) % num_stripes] =
-					em->start + (tmp + i) * map->stripe_len;
-
-			raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
-			if (map->type & BTRFS_BLOCK_GROUP_RAID6)
-				raid_map[(i+rot+1) % num_stripes] =
-					RAID6_Q_STRIPE;
-
 			*length = map->stripe_len;
 			stripe_index = 0;
 			stripe_offset = 0;
 		} else {
+			u64 tmp;
+
 			/*
 			 * Mirror #0 or #1 means the original data block.
 			 * Mirror #2 is RAID5 parity block.
@@ -5246,17 +5241,42 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		tgtdev_indexes = num_stripes;
 	}
 
-	bbio = kzalloc(btrfs_bio_size(num_alloc_stripes, tgtdev_indexes),
-		       GFP_NOFS);
+	bbio = alloc_btrfs_bio(num_alloc_stripes, tgtdev_indexes);
 	if (!bbio) {
-		kfree(raid_map);
 		ret = -ENOMEM;
 		goto out;
 	}
-	atomic_set(&bbio->error, 0);
 	if (dev_replace_is_ongoing)
 		bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes);
 
+	/* build raid_map */
+	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK &&
+	    need_raid_map && ((rw & (REQ_WRITE | REQ_GET_READ_MIRRORS)) ||
+	    mirror_num > 1)) {
+		u64 tmp;
+		int i, rot;
+
+		bbio->raid_map = (u64 *)((void *)bbio->stripes +
+				 sizeof(struct btrfs_bio_stripe) *
+				 num_alloc_stripes +
+				 sizeof(int) * tgtdev_indexes);
+
+		/* Work out the disk rotation on this stripe-set */
+		tmp = stripe_nr;
+		rot = do_div(tmp, num_stripes);
+
+		/* Fill in the logical address of each stripe */
+		tmp = stripe_nr * nr_data_stripes(map);
+		for (i = 0; i < nr_data_stripes(map); i++)
+			bbio->raid_map[(i+rot) % num_stripes] =
+				em->start + (tmp + i) * map->stripe_len;
+
+		bbio->raid_map[(i+rot) % map->num_stripes] = RAID5_P_STRIPE;
+		if (map->type & BTRFS_BLOCK_GROUP_RAID6)
+			bbio->raid_map[(i+rot+1) % num_stripes] =
+				RAID6_Q_STRIPE;
+	}
+
 	if (rw & REQ_DISCARD) {
 		int factor = 0;
 		int sub_stripes = 0;
@@ -5340,6 +5360,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 	if (rw & (REQ_WRITE | REQ_GET_READ_MIRRORS))
 		max_errors = btrfs_chunk_max_errors(map);
 
+	if (bbio->raid_map)
+		sort_parity_stripes(bbio, num_stripes);
+
 	tgtdev_indexes = 0;
 	if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
 	    dev_replace->tgtdev != NULL) {
@@ -5427,6 +5450,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 	}
 
 	*bbio_ret = bbio;
+	bbio->map_type = map->type;
 	bbio->num_stripes = num_stripes;
 	bbio->max_errors = max_errors;
 	bbio->mirror_num = mirror_num;
@@ -5443,10 +5467,6 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		bbio->stripes[0].physical = physical_to_patch_in_first_stripe;
 		bbio->mirror_num = map->num_stripes + 1;
 	}
-	if (raid_map) {
-		sort_parity_stripes(bbio, raid_map);
-		*raid_map_ret = raid_map;
-	}
 out:
 	if (dev_replace_is_ongoing)
 		btrfs_dev_replace_unlock(dev_replace);
@@ -5459,17 +5479,17 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
 		      struct btrfs_bio **bbio_ret, int mirror_num)
 {
 	return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
-				 mirror_num, NULL);
+				 mirror_num, 0);
 }
 
 /* For Scrub/replace */
 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, int rw,
 		     u64 logical, u64 *length,
 		     struct btrfs_bio **bbio_ret, int mirror_num,
-		     u64 **raid_map_ret)
+		     int need_raid_map)
 {
 	return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
-				 mirror_num, raid_map_ret);
+				 mirror_num, need_raid_map);
 }
 
 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
@@ -5511,8 +5531,7 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 		do_div(length, map->num_stripes / map->sub_stripes);
 	else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
 		do_div(length, map->num_stripes);
-	else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
-			      BTRFS_BLOCK_GROUP_RAID6)) {
+	else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
 		do_div(length, nr_data_stripes(map));
 		rmap_len = map->stripe_len * nr_data_stripes(map);
 	}
@@ -5565,7 +5584,7 @@ static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio, int e
 		bio_endio_nodec(bio, err);
 	else
 		bio_endio(bio, err);
-	kfree(bbio);
+	btrfs_put_bbio(bbio);
 }
 
 static void btrfs_end_bio(struct bio *bio, int err)
@@ -5808,7 +5827,6 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 	u64 logical = (u64)bio->bi_iter.bi_sector << 9;
 	u64 length = 0;
 	u64 map_length;
-	u64 *raid_map = NULL;
 	int ret;
 	int dev_nr = 0;
 	int total_devs = 1;
@@ -5819,7 +5837,7 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 
 	btrfs_bio_counter_inc_blocked(root->fs_info);
 	ret = __btrfs_map_block(root->fs_info, rw, logical, &map_length, &bbio,
-			      mirror_num, &raid_map);
+			      mirror_num, 1);
 	if (ret) {
 		btrfs_bio_counter_dec(root->fs_info);
 		return ret;
@@ -5832,15 +5850,13 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 	bbio->fs_info = root->fs_info;
 	atomic_set(&bbio->stripes_pending, bbio->num_stripes);
 
-	if (raid_map) {
+	if (bbio->raid_map) {
 		/* In this case, map_length has been set to the length of
 		   a single stripe; not the whole write */
 		if (rw & WRITE) {
-			ret = raid56_parity_write(root, bio, bbio,
-						  raid_map, map_length);
+			ret = raid56_parity_write(root, bio, bbio, map_length);
 		} else {
-			ret = raid56_parity_recover(root, bio, bbio,
-						    raid_map, map_length,
+			ret = raid56_parity_recover(root, bio, bbio, map_length,
 						    mirror_num, 1);
 		}
 
@@ -6238,17 +6254,22 @@ int btrfs_read_sys_array(struct btrfs_root *root)
 	struct extent_buffer *sb;
 	struct btrfs_disk_key *disk_key;
 	struct btrfs_chunk *chunk;
-	u8 *ptr;
-	unsigned long sb_ptr;
+	u8 *array_ptr;
+	unsigned long sb_array_offset;
 	int ret = 0;
 	u32 num_stripes;
 	u32 array_size;
 	u32 len = 0;
-	u32 cur;
+	u32 cur_offset;
 	struct btrfs_key key;
 
-	sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET,
-					  BTRFS_SUPER_INFO_SIZE);
+	ASSERT(BTRFS_SUPER_INFO_SIZE <= root->nodesize);
+	/*
+	 * This will create extent buffer of nodesize, superblock size is
+	 * fixed to BTRFS_SUPER_INFO_SIZE. If nodesize > sb size, this will
+	 * overallocate but we can keep it as-is, only the first page is used.
+	 */
+	sb = btrfs_find_create_tree_block(root, BTRFS_SUPER_INFO_OFFSET);
 	if (!sb)
 		return -ENOMEM;
 	btrfs_set_buffer_uptodate(sb);
@@ -6271,35 +6292,56 @@ int btrfs_read_sys_array(struct btrfs_root *root)
 	write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE);
 	array_size = btrfs_super_sys_array_size(super_copy);
 
-	ptr = super_copy->sys_chunk_array;
-	sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array);
-	cur = 0;
+	array_ptr = super_copy->sys_chunk_array;
+	sb_array_offset = offsetof(struct btrfs_super_block, sys_chunk_array);
+	cur_offset = 0;
+
+	while (cur_offset < array_size) {
+		disk_key = (struct btrfs_disk_key *)array_ptr;
+		len = sizeof(*disk_key);
+		if (cur_offset + len > array_size)
+			goto out_short_read;
 
-	while (cur < array_size) {
-		disk_key = (struct btrfs_disk_key *)ptr;
 		btrfs_disk_key_to_cpu(&key, disk_key);
 
-		len = sizeof(*disk_key); ptr += len;
-		sb_ptr += len;
-		cur += len;
+		array_ptr += len;
+		sb_array_offset += len;
+		cur_offset += len;
 
 		if (key.type == BTRFS_CHUNK_ITEM_KEY) {
-			chunk = (struct btrfs_chunk *)sb_ptr;
+			chunk = (struct btrfs_chunk *)sb_array_offset;
+			/*
+			 * At least one btrfs_chunk with one stripe must be
+			 * present, exact stripe count check comes afterwards
+			 */
+			len = btrfs_chunk_item_size(1);
+			if (cur_offset + len > array_size)
+				goto out_short_read;
+
+			num_stripes = btrfs_chunk_num_stripes(sb, chunk);
+			len = btrfs_chunk_item_size(num_stripes);
+			if (cur_offset + len > array_size)
+				goto out_short_read;
+
 			ret = read_one_chunk(root, &key, sb, chunk);
 			if (ret)
 				break;
-			num_stripes = btrfs_chunk_num_stripes(sb, chunk);
-			len = btrfs_chunk_item_size(num_stripes);
 		} else {
 			ret = -EIO;
 			break;
 		}
-		ptr += len;
-		sb_ptr += len;
-		cur += len;
+		array_ptr += len;
+		sb_array_offset += len;
+		cur_offset += len;
 	}
 	free_extent_buffer(sb);
 	return ret;
+
+out_short_read:
+	printk(KERN_ERR "BTRFS: sys_array too short to read %u bytes at offset %u\n",
+			len, cur_offset);
+	free_extent_buffer(sb);
+	return -EIO;
 }
 
 int btrfs_read_chunk_tree(struct btrfs_root *root)