From ea9cd9df2be56041e2d62b0e72c77695b03261f7 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 17 Oct 2017 13:00:41 +0800 Subject: btrfs-progs: Introduce function to fix unaligned device size Recent kernel introduced alignment check for dev item, however older kernel doesn't align device size when adding new device or shrinking existing device. This makes noisy kernel warning every time when any DEV_ITEM gets updated. Introduce function to fix device size on an unmounted filesystem. Reported-by: Asif Youssuff Reported-by: Rich Rauenzahn Signed-off-by: Qu Wenruo Reviewed-by: Nikolay Borisov Signed-off-by: David Sterba --- volumes.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) (limited to 'volumes.c') diff --git a/volumes.c b/volumes.c index e3654a4c..652f0087 100644 --- a/volumes.c +++ b/volumes.c @@ -2356,3 +2356,72 @@ u64 btrfs_stripe_length(struct btrfs_fs_info *fs_info, } return stripe_len; } + +/* + * Return 0 if size of @device is already good + * Return >0 if size of @device is not aligned but fixed without problems + * Return <0 if something wrong happened when aligning the size of @device + */ +int btrfs_fix_device_size(struct btrfs_fs_info *fs_info, + struct btrfs_device *device) +{ + struct btrfs_trans_handle *trans; + struct btrfs_key key; + struct btrfs_path path; + struct btrfs_root *chunk_root = fs_info->chunk_root; + struct btrfs_dev_item *di; + u64 old_bytes = device->total_bytes; + int ret; + + if (IS_ALIGNED(old_bytes, fs_info->sectorsize)) + return 0; + + /* Align the in-memory total_bytes first, and use it as correct size */ + device->total_bytes = round_down(device->total_bytes, + fs_info->sectorsize); + + key.objectid = BTRFS_DEV_ITEMS_OBJECTID; + key.type = BTRFS_DEV_ITEM_KEY; + key.offset = device->devid; + + trans = btrfs_start_transaction(chunk_root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + error("error starting transaction: %d (%s)", + ret, strerror(-ret)); + return ret; + } + + btrfs_init_path(&path); + ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1); + if (ret > 0) { + error("failed to find DEV_ITEM for devid %llu", device->devid); + ret = -ENOENT; + goto err; + } + if (ret < 0) { + error("failed to search chunk root: %d (%s)", + ret, strerror(-ret)); + goto err; + } + di = btrfs_item_ptr(path.nodes[0], path.slots[0], struct btrfs_dev_item); + btrfs_set_device_total_bytes(path.nodes[0], di, device->total_bytes); + btrfs_mark_buffer_dirty(path.nodes[0]); + ret = btrfs_commit_transaction(trans, chunk_root); + if (ret < 0) { + error("failed to commit current transaction: %d (%s)", + ret, strerror(-ret)); + btrfs_release_path(&path); + return ret; + } + btrfs_release_path(&path); + printf("Fixed device size for devid %llu, old size: %llu new size: %llu\n", + device->devid, old_bytes, device->total_bytes); + return 1; + +err: + /* We haven't modified anything, it's OK to commit current trans */ + btrfs_commit_transaction(trans, chunk_root); + btrfs_release_path(&path); + return ret; +} -- cgit v1.2.3