Btrfs: fix "mutually exclusive op is running" error code

The error code that is returned in response to starting a mutually
exclusive operation when there is one already running got silently
changed from EINVAL to EINPROGRESS by 5ac00add.  Returning EINPROGRESS
to, say, add_dev, when rm_dev is running is misleading.  Furthermore,
the operation itself may want to use EINPROGRESS for other purposes.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 77d8273..259dd52 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1340,7 +1340,7 @@ static noinline int btrfs_ioctl_resize(struct file *file,
                        1)) {
                pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
                mnt_drop_write_file(file);
-               return -EINPROGRESS;
+               return -EINVAL;
        }
 
        mutex_lock(&root->fs_info->volume_mutex);
@@ -2192,7 +2192,7 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
        if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
                        1)) {
                pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
-               return -EINPROGRESS;
+               return -EINVAL;
        }
        ret = mnt_want_write_file(file);
        if (ret) {
@@ -2266,7 +2266,7 @@ static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
        if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
                        1)) {
                pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
-               return -EINPROGRESS;
+               return -EINVAL;
        }
 
        mutex_lock(&root->fs_info->volume_mutex);
@@ -2303,7 +2303,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
                        1)) {
                pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
                mnt_drop_write_file(file);
-               return -EINPROGRESS;
+               return -EINVAL;
        }
 
        mutex_lock(&root->fs_info->volume_mutex);