Btrfs, replace: write raid56 parity into the replace target device

This function reused the code of parity scrub, and we just write
the right parity or corrected parity into the target device before
the parity scrub end.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index 89a8486c34b3ccced7d21ddb863013f58c559a5a..5ece565bc5f0cda1c38f4ad319e8fb52e24eacba 100644 (file)
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -2318,7 +2318,9 @@ static void raid_write_parity_end_io(struct bio *bio, int err)
 static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,
                                         int need_check)
 {
+       struct btrfs_bio *bbio = rbio->bbio;
        void *pointers[rbio->real_stripes];
+       DECLARE_BITMAP(pbitmap, rbio->stripe_npages);
        int nr_data = rbio->nr_data;
        int stripe;
        int pagenr;
@@ -2328,6 +2330,7 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,
        struct page *q_page = NULL;
        struct bio_list bio_list;
        struct bio *bio;
+       int is_replace = 0;
        int ret;
 
        bio_list_init(&bio_list);
@@ -2341,6 +2344,11 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,
                BUG();
        }
 
+       if (bbio->num_tgtdevs && bbio->tgtdev_map[rbio->scrubp]) {
+               is_replace = 1;
+               bitmap_copy(pbitmap, rbio->dbitmap, rbio->stripe_npages);
+       }
+
        /*
         * Because the higher layers(scrubber) are unlikely to
         * use this area of the disk again soon, so don't cache
@@ -2429,6 +2437,21 @@ writeback:
                        goto cleanup;
        }
 
+       if (!is_replace)
+               goto submit_write;
+
+       for_each_set_bit(pagenr, pbitmap, rbio->stripe_npages) {
+               struct page *page;
+
+               page = rbio_stripe_page(rbio, rbio->scrubp, pagenr);
+               ret = rbio_add_io_page(rbio, &bio_list, page,
+                                      bbio->tgtdev_map[rbio->scrubp],
+                                      pagenr, rbio->stripe_len);
+               if (ret)
+                       goto cleanup;
+       }
+
+submit_write:
        nr_data = bio_list_size(&bio_list);
        if (!nr_data) {
                /* Every parity is right */

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 7f95afcf9fd3d8976598daa2d88dd8f9b45a4279..0ae837fd676df4cb92dd7cd200fce2c42bf42c8d 100644 (file)
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -2714,7 +2714,7 @@ static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
                goto out;
 
        length = sparity->logic_end - sparity->logic_start + 1;
-       ret = btrfs_map_sblock(sctx->dev_root->fs_info, REQ_GET_READ_MIRRORS,
+       ret = btrfs_map_sblock(sctx->dev_root->fs_info, WRITE,
                               sparity->logic_start,
                               &length, &bbio, 0, &raid_map);
        if (ret || !bbio || !raid_map)