btrfsctl: add snapshot/subvolume destroy ioctl

resend Aaron Straus's patch

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/btrfsctl.c b/btrfsctl.c
index b323818..66c4e89 100644 (file)
--- a/btrfsctl.c
+++ b/btrfsctl.c
@@ -46,7 +46,7 @@ static inline int ioctl(int fd, int define, void *arg) { return 0; }
 static void print_usage(void)
 {
        printf("usage: btrfsctl [ -d file|dir] [ -s snap_name subvol|tree ]\n");
-       printf("                [-r size] [-A device] [-a] [-c]\n");
+       printf("                [-r size] [-A device] [-a] [-c] [-D dir .]\n");
        printf("\t-d filename: defragments one file\n");
        printf("\t-d directory: defragments the entire Btree\n");
        printf("\t-s snap_name dir: creates a new snapshot of dir\n");
@@ -55,6 +55,7 @@ static void print_usage(void)
        printf("\t-A device: scans the device file for a Btrfs filesystem\n");
        printf("\t-a: scans all devices for Btrfs filesystems\n");
        printf("\t-c: forces a single FS sync\n");
+       printf("\t-D: delete snapshot\n");
        printf("%s\n", BTRFS_BUILD_VERSION);
        exit(1);
 }
@@ -158,6 +159,18 @@ int main(int ac, char **av)
                                print_usage();
                        }
                        command = BTRFS_IOC_DEFRAG;
+               } else if (strcmp(av[i], "-D") == 0) {
+                       if (i >= ac - 1) {
+                               fprintf(stderr, "-D requires an arg\n");
+                               print_usage();
+                       }
+                       command = BTRFS_IOC_SNAP_DESTROY;
+                       name = av[i + 1];
+                       len = strlen(name);
+                       if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
+                               fprintf(stderr, "-D size too long\n");
+                               exit(1);
+                       }
                } else if (strcmp(av[i], "-A") == 0) {
                        if (i >= ac - 1) {
                                fprintf(stderr, "-A requires an arg\n");

diff --git a/ioctl.h b/ioctl.h
index a084f33..4410ac0 100644 (file)
--- a/ioctl.h
+++ b/ioctl.h
@@ -56,4 +56,7 @@ struct btrfs_ioctl_vol_args {
 /* 13 is for CLONE_RANGE */
 #define BTRFS_IOC_SUBVOL_CREATE _IOW(BTRFS_IOCTL_MAGIC, 14, \
                                   struct btrfs_ioctl_vol_args)
+
+#define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \
+                                  struct btrfs_ioctl_vol_args)
 #endif