1 files changed, 40 insertions, 12 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index ff2b35114972..0144790e296e 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -4879,13 +4879,15 @@ static inline int parity_smaller(u64 a, u64 b)
 static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map)
 {
         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 < bbio->num_stripes - 1; i++) {
+                for (i = 0; i < real_stripes - 1; i++) {
                         if (parity_smaller(raid_map[i], raid_map[i+1])) {
                                 s = bbio->stripes[i];
                                 l = raid_map[i];
@@ -4893,6 +4895,14 @@ static void sort_parity_stripes(struct btrfs_bio *bbio, u64 *raid_map)
                                 raid_map[i] = 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;
+                                }
+
                                 again = 1;
                         }
                 }
@@ -4921,6 +4931,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
         int ret = 0;
         int num_stripes;
         int max_errors = 0;
+        int tgtdev_indexes = 0;
         struct btrfs_bio *bbio = NULL;
         struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
         int dev_replace_is_ongoing = 0;
@@ -5159,15 +5170,14 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                                 BTRFS_BLOCK_GROUP_RAID6)) {
                 u64 tmp;
 
-                if (bbio_ret && ((rw & REQ_WRITE) || mirror_num > 1)
-                    && raid_map_ret) {
+                if (raid_map_ret &&
+                    ((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);
-
-                        stripe_index = do_div(stripe_nr, nr_data_stripes(map));
+                        do_div(stripe_nr, stripe_len * nr_data_stripes(map));
 
                         /* RAID[56] write or recovery. Return all stripes */
                         num_stripes = map->num_stripes;
@@ -5233,14 +5243,19 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                         num_alloc_stripes <<= 1;
                 if (rw & REQ_GET_READ_MIRRORS)
                         num_alloc_stripes++;
+                tgtdev_indexes = num_stripes;
         }
-        bbio = kzalloc(btrfs_bio_size(num_alloc_stripes), GFP_NOFS);
+
+        bbio = kzalloc(btrfs_bio_size(num_alloc_stripes, tgtdev_indexes),
+                       GFP_NOFS);
         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);
 
         if (rw & REQ_DISCARD) {
                 int factor = 0;
@@ -5325,6 +5340,7 @@ 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);
 
+        tgtdev_indexes = 0;
         if (dev_replace_is_ongoing && (rw & (REQ_WRITE | REQ_DISCARD)) &&
             dev_replace->tgtdev != NULL) {
                 int index_where_to_add;
@@ -5353,8 +5369,10 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                                 new->physical = old->physical;
                                 new->length = old->length;
                                 new->dev = dev_replace->tgtdev;
+                                bbio->tgtdev_map[i] = index_where_to_add;
                                 index_where_to_add++;
                                 max_errors++;
+                                tgtdev_indexes++;
                         }
                 }
                 num_stripes = index_where_to_add;
@@ -5400,7 +5418,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                                 tgtdev_stripe->length =
                                         bbio->stripes[index_srcdev].length;
                                 tgtdev_stripe->dev = dev_replace->tgtdev;
+                                bbio->tgtdev_map[index_srcdev] = num_stripes;
 
+                                tgtdev_indexes++;
                                 num_stripes++;
                         }
                 }
@@ -5410,6 +5430,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
         bbio->num_stripes = num_stripes;
         bbio->max_errors = max_errors;
         bbio->mirror_num = mirror_num;
+        bbio->num_tgtdevs = tgtdev_indexes;
 
         /*
          * this is the case that REQ_READ && dev_replace_is_ongoing &&
@@ -5441,6 +5462,16 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
                                  mirror_num, NULL);
 }
 
+/* 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)
+{
+        return __btrfs_map_block(fs_info, rw, logical, length, bbio_ret,
+                                 mirror_num, raid_map_ret);
+}
+
 int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
                      u64 chunk_start, u64 physical, u64 devid,
                      u64 **logical, int *naddrs, int *stripe_len)
@@ -5810,12 +5841,9 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
                 } else {
                         ret = raid56_parity_recover(root, bio, bbio,
                                                     raid_map, map_length,
-                                                    mirror_num);
+                                                    mirror_num, 1);
                 }
-                /*
-                 * FIXME, replace dosen't support raid56 yet, please fix
-                 * it in the future.
-                 */
+
                 btrfs_bio_counter_dec(root->fs_info);
                 return ret;
         }