diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index ab34179d7cbc8..2854f4a407878 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3217,11 +3217,15 @@ static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info, struct btrfs_ioctl_fs_info_args *fi_args; struct btrfs_device *device; struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + u64 flags_in; int ret = 0; - fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); - if (!fi_args) - return -ENOMEM; + fi_args = memdup_user(arg, sizeof(*fi_args)); + if (IS_ERR(fi_args)) + return PTR_ERR(fi_args); + + flags_in = fi_args->flags; + memset(fi_args, 0, sizeof(*fi_args)); rcu_read_lock(); fi_args->num_devices = fs_devices->num_devices; @@ -3237,6 +3241,12 @@ static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info, fi_args->sectorsize = fs_info->sectorsize; fi_args->clone_alignment = fs_info->sectorsize; + if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) { + fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy); + fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy); + fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO; + } + if (copy_to_user(arg, fi_args, sizeof(*fi_args))) ret = -EFAULT; diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index e6b6cb0f8bc6a..24f6848ad78ec 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -243,6 +243,13 @@ struct btrfs_ioctl_dev_info_args { __u8 path[BTRFS_DEVICE_PATH_NAME_MAX]; /* out */ }; +/* + * Retrieve information about the filesystem + */ + +/* Request information about checksum type and size */ +#define BTRFS_FS_INFO_FLAG_CSUM_INFO (1 << 0) + struct btrfs_ioctl_fs_info_args { __u64 max_id; /* out */ __u64 num_devices; /* out */ @@ -250,8 +257,11 @@ struct btrfs_ioctl_fs_info_args { __u32 nodesize; /* out */ __u32 sectorsize; /* out */ __u32 clone_alignment; /* out */ - __u32 reserved32; - __u64 reserved[122]; /* pad to 1k */ + /* See BTRFS_FS_INFO_FLAG_* */ + __u16 csum_type; /* out */ + __u16 csum_size; /* out */ + __u64 flags; /* in/out */ + __u8 reserved[968]; /* pad to 1k */ }; /*