From 5a1972bd9fd4b2fb1bac8b7a0b636d633d8717e3 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 16 Apr 2014 17:02:32 +0800 Subject: [PATCH] btrfs: Add ctime/mtime update for btrfs device add/remove. Btrfs will send uevent to udev inform the device change, but ctime/mtime for the block device inode is not udpated, which cause libblkid used by btrfs-progs unable to detect device change and use old cache, causing 'btrfs dev scan; btrfs dev rmove; btrfs dev scan' give an error message. Reported-by: Tsutomu Itoh Cc: Karel Zak Signed-off-by: Qu Wenruo Signed-off-by: Chris Mason --- fs/btrfs/volumes.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 3b761a456acd..ad8e342c4b78 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1452,6 +1452,22 @@ out: return ret; } +/* + * Function to update ctime/mtime for a given device path. + * Mainly used for ctime/mtime based probe like libblkid. + */ +static void update_dev_time(char *path_name) +{ + struct file *filp; + + filp = filp_open(path_name, O_RDWR, 0); + if (!filp) + return; + file_update_time(filp); + filp_close(filp, NULL); + return; +} + static int btrfs_rm_dev_item(struct btrfs_root *root, struct btrfs_device *device) { @@ -1704,10 +1720,14 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path) ret = 0; - /* Notify udev that device has changed */ - if (bdev) + if (bdev) { + /* Notify udev that device has changed */ btrfs_kobject_uevent(bdev, KOBJ_CHANGE); + /* Update ctime/mtime for device path for libblkid */ + update_dev_time(device_path); + } + error_brelse: brelse(bh); if (bdev) @@ -2146,6 +2166,8 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path) ret = btrfs_commit_transaction(trans, root); } + /* Update ctime/mtime for libblkid */ + update_dev_time(device_path); return ret; error_trans: -- 2.20.1