Provide the basic information about filesystem through the ioctl: * b-tree node size (same as leaf size) * sector size * expected alignment of CLONE_RANGE and EXTENT_SAME ioctl arguments
Backward compatibility: if the values are 0, kernel does not provide this information, the applications should ignore them. Signed-off-by: David Sterba <[email protected]> --- fs/btrfs/ioctl.c | 4 ++++ include/uapi/linux/btrfs.h | 6 +++++- 2 files changed, 9 insertions(+), 1 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 2ad7de94efef..74530f226e50 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -2574,6 +2574,10 @@ static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg) } mutex_unlock(&fs_devices->device_list_mutex); + fi_args->nodesize = root->fs_info->super_copy->nodesize; + fi_args->sectorsize = root->fs_info->super_copy->sectorsize; + fi_args->clone_alignment = root->fs_info->super_copy->sectorsize; + 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 b4d69092fbdb..aad9391e0a6d 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -181,7 +181,11 @@ struct btrfs_ioctl_fs_info_args { __u64 max_id; /* out */ __u64 num_devices; /* out */ __u8 fsid[BTRFS_FSID_SIZE]; /* out */ - __u64 reserved[124]; /* pad to 1k */ + __u32 nodesize; /* out */ + __u32 sectorsize; /* out */ + __u32 clone_alignment; /* out */ + __u32 reserved32; + __u64 reserved[122]; /* pad to 1k */ }; struct btrfs_ioctl_feature_flags { -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
