So we don't have to add new structures as we create more ioctls
for snapshots/subvolumes.
Now to create async snapshot, set BTRFS_SUBVOL_CREATE_SNAP_ASYNC bit
of vol_arg_v2->flags, and then call ioctl(BTRFS_IOCT_SNAP_CREATE_V2).
Signed-off-by: Li Zefan <l...@cn.fujitsu.com>
---
fs/btrfs/ioctl.c | 34 +++++++++++++++++++++-------------
fs/btrfs/ioctl.h | 14 +++++++++-----
2 files changed, 30 insertions(+), 18 deletions(-)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f1c9bb4..dc953bc 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -947,23 +947,31 @@ out:
static noinline int btrfs_ioctl_snap_create(struct file *file,
void __user *arg, int subvol,
- int async)
+ bool v2)
{
struct btrfs_ioctl_vol_args *vol_args = NULL;
- struct btrfs_ioctl_async_vol_args *async_vol_args = NULL;
+ struct btrfs_ioctl_vol_args_v2 *vol_args_v2 = NULL;
char *name;
u64 fd;
u64 transid = 0;
+ bool async = false;
int ret;
- if (async) {
- async_vol_args = memdup_user(arg, sizeof(*async_vol_args));
- if (IS_ERR(async_vol_args))
- return PTR_ERR(async_vol_args);
+ if (v2) {
+ vol_args_v2 = memdup_user(arg, sizeof(*vol_args_v2));
+ if (IS_ERR(vol_args_v2))
+ return PTR_ERR(vol_args_v2);
- name = async_vol_args->name;
- fd = async_vol_args->fd;
- async_vol_args->name[BTRFS_SNAPSHOT_NAME_MAX] = '\0';
+ if (vol_args_v2->flags & ~BTRFS_SUBVOL_CREATE_SNAP_ASYNC) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ name = vol_args_v2->name;
+ fd = vol_args_v2->fd;
+ vol_args_v2->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
+ if (vol_args_v2->flags & BTRFS_SUBVOL_CREATE_SNAP_ASYNC)
+ async = true;
} else {
vol_args = memdup_user(arg, sizeof(*vol_args));
if (IS_ERR(vol_args))
@@ -978,13 +986,13 @@ static noinline int btrfs_ioctl_snap_create(struct file
*file,
if (!ret && async) {
if (copy_to_user(arg +
- offsetof(struct btrfs_ioctl_async_vol_args,
+ offsetof(struct btrfs_ioctl_vol_args_v2,
transid), &transid, sizeof(transid)))
return -EFAULT;
}
-
+out:
kfree(vol_args);
- kfree(async_vol_args);
+ kfree(vol_args_v2);
return ret;
}
@@ -2246,7 +2254,7 @@ long btrfs_ioctl(struct file *file, unsigned int
return btrfs_ioctl_getversion(file, argp);
case BTRFS_IOC_SNAP_CREATE:
return btrfs_ioctl_snap_create(file, argp, 0, 0);
- case BTRFS_IOC_SNAP_CREATE_ASYNC:
+ case BTRFS_IOC_SNAP_CREATE_V2:
return btrfs_ioctl_snap_create(file, argp, 0, 1);
case BTRFS_IOC_SUBVOL_CREATE:
return btrfs_ioctl_snap_create(file, argp, 1, 0);
diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h
index 17c99eb..9affc49 100644
--- a/fs/btrfs/ioctl.h
+++ b/fs/btrfs/ioctl.h
@@ -30,11 +30,15 @@ struct btrfs_ioctl_vol_args {
char name[BTRFS_PATH_NAME_MAX + 1];
};
-#define BTRFS_SNAPSHOT_NAME_MAX 4079
-struct btrfs_ioctl_async_vol_args {
+#define BTRFS_SUBVOL_CREATE_SNAP_ASYNC (1ULL << 0)
+
+#define BTRFS_SUBVOL_NAME_MAX 4039
+struct btrfs_ioctl_vol_args_v2 {
__s64 fd;
__u64 transid;
- char name[BTRFS_SNAPSHOT_NAME_MAX + 1];
+ __u64 flags;
+ __u64 unused[4];
+ char name[BTRFS_SUBVOL_NAME_MAX + 1];
};
#define BTRFS_INO_LOOKUP_PATH_MAX 4080
@@ -187,6 +191,6 @@ struct btrfs_ioctl_space_args {
struct btrfs_ioctl_space_args)
#define BTRFS_IOC_START_SYNC _IOR(BTRFS_IOCTL_MAGIC, 24, __u64)
#define BTRFS_IOC_WAIT_SYNC _IOW(BTRFS_IOCTL_MAGIC, 22, __u64)
-#define BTRFS_IOC_SNAP_CREATE_ASYNC _IOW(BTRFS_IOCTL_MAGIC, 23, \
- struct btrfs_ioctl_async_vol_args)
+#define BTRFS_IOC_SNAP_CREATE_V2 _IOW(BTRFS_IOCTL_MAGIC, 23, \
+ struct btrfs_ioctl_vol_args_v2)
#endif
--
1.6.3
--
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