From 7269fa15702ba7f925936a31125571ebb4398965 Mon Sep 17 00:00:00 2001 From: Gui Hecheng Date: Thu, 13 Nov 2014 09:19:29 +0800 Subject: [PATCH] btrfs-progs: fix wrong num_devices for btrfs fi show with seed devices The @fi_args->num_devices in @get_fs_info() does not include seed devices. We could just correct it by searching the chunk tree and count how many dev_items there are in total which includes seed devices. Signed-off-by: Gui Hecheng Signed-off-by: David Sterba --- utils.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) diff --git a/utils.c b/utils.c index 16b10e0..8885669 100644 --- a/utils.c +++ b/utils.c @@ -1815,6 +1815,75 @@ int get_device_info(int fd, u64 devid, return ret ? -errno : 0; } +static u64 find_max_device_id(struct btrfs_ioctl_search_args *search_args, + int nr_items) +{ + struct btrfs_dev_item *dev_item; + char *buf = search_args->buf; + + buf += (nr_items - 1) * (sizeof(struct btrfs_ioctl_search_header) + + sizeof(struct btrfs_dev_item)); + buf += sizeof(struct btrfs_ioctl_search_header); + + dev_item = (struct btrfs_dev_item *)buf; + + return btrfs_stack_device_id(dev_item); +} + +static int search_chunk_tree_for_fs_info(int fd, + struct btrfs_ioctl_fs_info_args *fi_args) +{ + int ret; + int max_items; + u64 start_devid = 1; + struct btrfs_ioctl_search_args search_args; + struct btrfs_ioctl_search_key *search_key = &search_args.key; + + fi_args->num_devices = 0; + + max_items = BTRFS_SEARCH_ARGS_BUFSIZE + / (sizeof(struct btrfs_ioctl_search_header) + + sizeof(struct btrfs_dev_item)); + + search_key->tree_id = BTRFS_CHUNK_TREE_OBJECTID; + search_key->min_objectid = BTRFS_DEV_ITEMS_OBJECTID; + search_key->max_objectid = BTRFS_DEV_ITEMS_OBJECTID; + search_key->min_type = BTRFS_DEV_ITEM_KEY; + search_key->max_type = BTRFS_DEV_ITEM_KEY; + search_key->min_transid = 0; + search_key->max_transid = (u64)-1; + search_key->nr_items = max_items; + search_key->max_offset = (u64)-1; + +again: + search_key->min_offset = start_devid; + + ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &search_args); + if (ret < 0) + return -errno; + + fi_args->num_devices += (u64)search_key->nr_items; + + if (search_key->nr_items == max_items) { + start_devid = find_max_device_id(&search_args, + search_key->nr_items) + 1; + goto again; + } + + /* get the lastest max_id to stay consistent with the num_devices */ + if (search_key->nr_items == 0) + /* + * last tree_search returns an empty buf, use the devid of + * the last dev_item of the previous tree_search + */ + fi_args->max_id = start_devid - 1; + else + fi_args->max_id = find_max_device_id(&search_args, + search_key->nr_items); + + return 0; +} + /* * For a given path, fill in the ioctl fs_ and info_ args. * If the path is a btrfs mountpoint, fill info for all devices. @@ -1894,6 +1963,13 @@ int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args *fi_args, ret = -errno; goto out; } + + /* + * The fs_args->num_devices does not include seed devices + */ + ret = search_chunk_tree_for_fs_info(fd, fi_args); + if (ret) + goto out; } if (!fi_args->num_devices) -- 2.7.4