Re: [PATCH V2] btrfs-progs: device add should check existing FS before adding

[Anand Jain <anand.jain@oracle.com>]

  wrong patch sent. Please ignore this. sorry.


On 09/29/2013 11:15 PM, Anand Jain wrote:
> as of now, when 'btrfs device add' adds a device it doesn't
> check if the given device contains an existing FS. This
> patch will change that to check the same. which when true
> add will fail, and ask user to use -f option to overwrite.
>
> further, since now we have test_dev_for_mkfs() function
> to check if a disk can be used, so this patch will also
> use this function to test the given device before adding.
>
> v2: worked on review comment
>      rebase on 20130920, update man page and review comments
>
> Signed-off-by: Anand Jain <anand.jain@oracle.com>
> ---
>   cmds-device.c  | 36 +++++++++++-------------------------
>   man/btrfs.8.in |  6 ++++--
>   2 files changed, 15 insertions(+), 27 deletions(-)
>
> diff --git a/cmds-device.c b/cmds-device.c
> index 12c802e..7cfc347 100644
> --- a/cmds-device.c
> +++ b/cmds-device.c
> @@ -40,6 +40,7 @@ static const char * const cmd_add_dev_usage[] = {
>   	"btrfs device add [options] <device> [<device>...] <path>",
>   	"Add a device to a filesystem",
>   	"-K|--nodiscard    do not perform whole device TRIM",
> +	"-f|--force        force overwrite existing filesystem on the disk",
>   	NULL
>   };
>
> @@ -49,14 +50,17 @@ static int cmd_add_dev(int argc, char **argv)
>   	int	i, fdmnt, ret=0, e;
>   	DIR	*dirstream = NULL;
>   	int discard = 1;
> +	int force = 0;
> +	char estr[100];
>
>   	while (1) {
>   		int long_index;
>   		static struct option long_options[] = {
>   			{ "nodiscard", optional_argument, NULL, 'K'},
> +			{ "force", no_argument, NULL, 'f'},
>   			{ 0, 0, 0, 0 }
>   		};
> -		int c = getopt_long(argc, argv, "K", long_options,
> +		int c = getopt_long(argc, argv, "Kf", long_options,
>   					&long_index);
>   		if (c < 0)
>   			break;
> @@ -64,6 +68,9 @@ static int cmd_add_dev(int argc, char **argv)
>   		case 'K':
>   			discard = 0;
>   			break;
> +		case 'f':
> +			force = 1;
> +			break;
>   		default:
>   			usage(cmd_add_dev_usage);
>   		}
> @@ -86,19 +93,11 @@ static int cmd_add_dev(int argc, char **argv)
>   		struct btrfs_ioctl_vol_args ioctl_args;
>   		int	devfd, res;
>   		u64 dev_block_count = 0;
> -		struct stat st;
>   		int mixed = 0;
>
> -		res = check_mounted(argv[i]);
> -		if (res < 0) {
> -			fprintf(stderr, "error checking %s mount status\n",
> -				argv[i]);
> -			ret++;
> -			continue;
> -		}
> -		if (res == 1) {
> -			fprintf(stderr, "%s is mounted\n", argv[i]);
> -			ret++;
> +		res = test_dev_for_mkfs(argv[i], force, estr);
> +		if (res) {
> +			fprintf(stderr, "%s", estr);
>   			continue;
>   		}
>
> @@ -108,19 +107,6 @@ static int cmd_add_dev(int argc, char **argv)
>   			ret++;
>   			continue;
>   		}
> -		res = fstat(devfd, &st);
> -		if (res) {
> -			fprintf(stderr, "ERROR: Unable to stat '%s'\n", argv[i]);
> -			close(devfd);
> -			ret++;
> -			continue;
> -		}
> -		if (!S_ISBLK(st.st_mode)) {
> -			fprintf(stderr, "ERROR: '%s' is not a block device\n", argv[i]);
> -			close(devfd);
> -			ret++;
> -			continue;
> -		}
>
>   		res = btrfs_prepare_device(devfd, argv[i], 1, &dev_block_count,
>   					   0, &mixed, discard);
> diff --git a/man/btrfs.8.in b/man/btrfs.8.in
> index 60e02bb..a65ed93 100644
> --- a/man/btrfs.8.in
> +++ b/man/btrfs.8.in
> @@ -47,7 +47,7 @@ btrfs \- control a btrfs filesystem
>   \fBbtrfs\fP \fB[filesystem] balance status\fP [-v] \fI<path>\fP
>   .PP
>   .PP
> -\fBbtrfs\fP \fBdevice add\fP [-K] \fI<device>\fP [\fI<device>...\fP] \fI<path>\fP
> +\fBbtrfs\fP \fBdevice add\fP [-Kf] \fI<device>\fP [\fI<device>...\fP] \fI<path>\fP
>   .PP
>   \fBbtrfs\fP \fBdevice delete\fP \fI<device>\fP [\fI<device>...\fP] \fI<path>\fP
>   .PP
> @@ -390,7 +390,7 @@ be verbose
>   .RE
>   .TP
>
> -\fBdevice add\fR\fI [-K] <dev> \fP[\fI<dev>...\fP] \fI<path>\fR
> +\fBdevice add\fR\fI [-Kf] <dev> \fP[\fI<dev>...\fP] \fI<path>\fR
>   Add device(s) to the filesystem identified by \fI<path>\fR.
>   If applicable, a whole device discard (TRIM) operation is performed.
>   .RS
> @@ -398,6 +398,8 @@ If applicable, a whole device discard (TRIM) operation is performed.
>   \fIOptions\fR
>   .IP "\fB-K|--nodiscard\fP" 5
>   do not perform discard by default
> +.IP "\fB-f|--force\fP" 5
> +force overwrite of existing filesystem on the given disk(s)
>   .RE
>   .TP
>
>