From c5868f8362f5620302c66848d400368f8d4b45f8 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Wed, 17 Feb 2016 15:24:14 +0100 Subject: [PATCH] btrfs: add GET_SUPPORTED_FEATURES to the control device ioctls The control device is accessible when no filesystem is mounted and we may want to query features supported by the module. This is already possible using the sysfs files, this ioctl is for parity and convenience. Reviewed-by: Anand Jain Signed-off-by: David Sterba --- fs/btrfs/ctree.h | 1 + fs/btrfs/ioctl.c | 3 +-- fs/btrfs/super.c | 4 ++++ 3 files changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index bfe4a337fb4d..47bc50fd4f55 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -4089,6 +4089,7 @@ void btrfs_test_inode_set_ops(struct inode *inode); /* ioctl.c */ long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); +int btrfs_ioctl_get_supported_features(struct file *file, void __user *arg); void btrfs_update_iflags(struct inode *inode); void btrfs_inherit_iflags(struct inode *inode, struct inode *dir); int btrfs_is_empty_uuid(u8 *uuid); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 952172ca7e45..f4c6ed5c5300 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -5187,8 +5187,7 @@ out_unlock: .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \ .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix } -static int btrfs_ioctl_get_supported_features(struct file *file, - void __user *arg) +int btrfs_ioctl_get_supported_features(struct file *file, void __user *arg) { static const struct btrfs_ioctl_feature_flags features[3] = { INIT_FEATURE_FLAGS(SUPP), diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index d41e09fe8e38..dda6f64dfd73 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -2163,6 +2163,10 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd, break; ret = !(fs_devices->num_devices == fs_devices->total_devices); break; + case BTRFS_IOC_GET_SUPPORTED_FEATURES: + ret = btrfs_ioctl_get_supported_features(NULL, + (void __user*)arg); + break; } kfree(vol); -- 2.20.1