Again this is just a proof of concept, though it does work in the basic case of just btrfsctl -m /mnt/point I''d just like to make sure this is an acceptable approach. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> --- btrfsctl.c | 7 +++++++ ioctl.h | 2 ++ 2 files changed, 9 insertions(+), 0 deletions(-) diff --git a/btrfsctl.c b/btrfsctl.c index 064c0d0..8fc78ba 100644 --- a/btrfsctl.c +++ b/btrfsctl.c @@ -58,6 +58,8 @@ static void print_usage(void) printf("\t-c: forces a single FS sync\n"); printf("\t-D: delete snapshot\n"); printf("\t-l file: listing snapshot/subvolume under a subvolume\n"); + printf("\t-m [tree id] directory: set the default mounted subvolume" + " to the [tree id] or the directory\n"); printf("%s\n", BTRFS_BUILD_VERSION); exit(1); } @@ -266,6 +268,7 @@ int main(int ac, char **av) unsigned long command = 0; int len; char *fullpath; + u64 objectid = 0; if (ac == 2 && strcmp(av[1], "-a") == 0) { fprintf(stderr, "Scanning for Btrfs filesystems\n"); @@ -380,6 +383,8 @@ int main(int ac, char **av) exit(1); } command = BTRFS_IOC_SNAP_LISTING; + } else if (strcmp(av[1], "-m") == 0) { + command = BTRFS_IOC_DEFAULT_SUBVOL; } } if (command == 0) { @@ -410,6 +415,8 @@ int main(int ac, char **av) ret = ioctl(snap_fd, command, &args); } else if (command == BTRFS_IOC_SNAP_LISTING) { ret = btrfs_list_subvolumes(snap_fd, command); + } else if (command == BTRFS_IOC_DEFAULT_SUBVOL) { + ret = ioctl(fd, command, &objectid); } else ret = ioctl(fd, command, &args); if (ret < 0) { diff --git a/ioctl.h b/ioctl.h index 19020cb..70fc15d 100644 --- a/ioctl.h +++ b/ioctl.h @@ -91,4 +91,6 @@ struct btrfs_ioctl_subvol_leaf { struct btrfs_ioctl_vol_args) #define BTRFS_IOC_SNAP_LISTING _IOWR(BTRFS_IOCTL_MAGIC, 16, \ struct btrfs_ioctl_subvol_args) +#define BTRFS_IOC_DEFAULT_SUBVOL _IOW(BTRFS_IOCTL_MAGIC, 17, u64) + #endif -- 1.5.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html