From 6fad823f4998cdff49c443891a0acc9f1bc289f9 Mon Sep 17 00:00:00 2001 From: Liu Bo Date: Tue, 14 Mar 2017 13:33:59 -0700 Subject: [PATCH] Btrfs: do not add extra mirror when dev_replace target dev is not available With this, we can avoid allocating memory for dev replace copies if the target dev is not available. Reviewed-by: Qu Wenruo Signed-off-by: Liu Bo Signed-off-by: David Sterba --- fs/btrfs/volumes.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index f27f9cebce24..8cc40268c50c 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -5157,7 +5157,8 @@ int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) free_extent_map(em); btrfs_dev_replace_lock(&fs_info->dev_replace, 0); - if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) + if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace) && + fs_info->dev_replace.tgtdev) ret++; btrfs_dev_replace_unlock(&fs_info->dev_replace, 0); @@ -5845,7 +5846,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, } num_alloc_stripes = num_stripes; - if (dev_replace_is_ongoing) { + if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL) { if (op == BTRFS_MAP_WRITE) num_alloc_stripes <<= 1; if (op == BTRFS_MAP_GET_READ_MIRRORS) @@ -5858,7 +5859,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, ret = -ENOMEM; goto out; } - if (dev_replace_is_ongoing) + if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL) bbio->tgtdev_map = (int *)(bbio->stripes + num_alloc_stripes); /* build raid_map */ -- 2.20.1