Re: [PATCH 2/3] btrfs: implement 'async-snapshot' command

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Saturday, 30 October, 2010, Sage Weil wrote:
> This is identical to 'snapshot', but uses the new async snapshot creation
> ioctl, and prints out the transid the new snapshot will be committed
> with.
> 
> Signed-off-by: Sage Weil <sage@xxxxxxxxxxxx>
> ---
>  btrfs.c      |    8 +++++++-
>  btrfs_cmds.c |   32 +++++++++++++++++++++++++++-----
>  btrfs_cmds.h |    3 ++-
>  3 files changed, 36 insertions(+), 7 deletions(-)
> 
> diff --git a/btrfs.c b/btrfs.c
> index 46314cf..c4b9a31 100644
> --- a/btrfs.c
> +++ b/btrfs.c
> @@ -44,11 +44,17 @@ static struct Command commands[] = {
>  	/*
>  		avoid short commands different for the case only
>  	*/
> -	{ do_clone, 2,
> +	{ do_create_snap, 2,
>  	  "subvolume snapshot", "<source> [<dest>/]<name>\n"
>  		"Create a writable snapshot of the subvolume <source> with\n"
>  		"the name <name> in the <dest> directory."
>  	},
> +	{ do_create_snap_async, 2,
> +	  "subvolume async-snapshot", "<source> [<dest>/]<name>\n"
> +		"Create a writable snapshot of the subvolume <source> with\n"
> +		"the name <name> in the <dest> directory.  Do not wait for\n"
> +	        "the snapshot creation to commit to disk before returning."
> +	},

Why create another command ? I think that it is better add a switch like

btrfs subvolume snapshot [--async] <source> [<dest>/]<name>

	Create a writable snapshot of the subvolume <source> with
	the name <name> in the <dest> directory.  If --async is
	passed, do not wait for the snapshot creation to commit to
	disk before returning.

In any case, please update the man page too.



>  	{ do_delete_subvolume, 1,
>  	  "subvolume delete", "<subvolume>\n"
>  		"Delete the subvolume <subvolume>."
> diff --git a/btrfs_cmds.c b/btrfs_cmds.c
> index 8031c58..6da5862 100644
> --- a/btrfs_cmds.c
> +++ b/btrfs_cmds.c
> @@ -307,7 +307,7 @@ int do_subvol_list(int argc, char **argv)
>  	return 0;
>  }
>  
> -int do_clone(int argc, char **argv)
> +static int create_snap(int argc, char **argv, int async)
>  {
>  	char	*subvol, *dst;
>  	int	res, fd, fddst, len;
> @@ -316,7 +316,6 @@ int do_clone(int argc, char **argv)
>  
>  	subvol = argv[1];
>  	dst = argv[2];
> -	struct btrfs_ioctl_vol_args	args;
>  
>  	res = test_issubvolume(subvol);
>  	if(res<0){
> @@ -374,9 +373,22 @@ int do_clone(int argc, char **argv)
>  
>  	printf("Create a snapshot of '%s' in '%s/%s'\n",
>  	       subvol, dstdir, newname);
> -	args.fd = fd;
> -	strcpy(args.name, newname);
> -	res = ioctl(fddst, BTRFS_IOC_SNAP_CREATE, &args);
> +	if (async) {
> +		struct btrfs_ioctl_async_vol_args	async_args;
> +		async_args.fd = fd;
> +		async_args.transid = 0;
> +		strcpy(async_args.name, newname);
> +		res = ioctl(fddst, BTRFS_IOC_SNAP_CREATE_ASYNC, &async_args);
> +		if (res == 0)
> +			printf("transid %llu\n",
> +			       (unsigned long long)async_args.transid);
> +	} else {
> +		struct btrfs_ioctl_vol_args	args;
> +
> +		args.fd = fd;
> +		strcpy(args.name, newname);
> +		res = ioctl(fddst, BTRFS_IOC_SNAP_CREATE, &args);
> +	}
>  
>  	close(fd);
>  	close(fddst);
> @@ -390,6 +402,16 @@ int do_clone(int argc, char **argv)
>  
>  }
>  
> +int do_create_snap_async(int argc, char **argv)
> +{
> +	return create_snap(argc, argv, 1);
> +}
> +
> +int do_create_snap(int argc, char **argv)
> +{
> +	return create_snap(argc, argv, 0);
> +}
> +
>  int do_delete_subvolume(int argc, char **argv)
>  {
>  	int	res, fd, len;
> diff --git a/btrfs_cmds.h b/btrfs_cmds.h
> index 7bde191..c44dc79 100644
> --- a/btrfs_cmds.h
> +++ b/btrfs_cmds.h
> @@ -15,7 +15,8 @@
>   */
>  
>  /* btrfs_cmds.c*/
> -int do_clone(int nargs, char **argv);
> +int do_create_snap(int nargs, char **argv);
> +int do_create_snap_async(int nargs, char **argv);
>  int do_delete_subvolume(int nargs, char **argv);
>  int do_create_subvol(int nargs, char **argv);
>  int do_fssync(int nargs, char **argv);
> -- 
> 1.7.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 


-- 
gpg key@ keyserver.linux.it: Goffredo Baroncelli (ghigo) <kreijack@xxxxxxxxx>
Key fingerprint = 4769 7E51 5293 D36C 814E  C054 BF04 F161 3DC5 0512
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Filesystem Development]     [Linux NFS]     [Linux NILFS]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux