Re: [PATCH] Add method for triggering Sanitize command

[Subhash Jadavani <subhashj@codeaurora.org>]

On 3/22/2013 10:42 PM, Chris Ball wrote:
> Hi,
>
> On Fri, Mar 22 2013, Subhash Jadavani wrote:
>> On 3/20/2013 5:28 PM, Yaniv Gardi wrote:
>>> This patch adds a method to trigger Sanitize command to MMC.
>>> The Sanitize command is used for deleting the unmapped memory region
>>> of the MMC device.
>>>
>>> Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
>>>
>>> diff --git a/mmc.c b/mmc.c
>>> index a2de863..174d9a4 100644
>>> --- a/mmc.c
>>> +++ b/mmc.c
>>> @@ -90,6 +90,11 @@ static struct Command commands[] = {
>>>    		"Permanently disable the eMMC H/W Reset feature on <device>.\nNOTE!  This is a one-time programmable (unreversible) change.",
>>>    	  NULL
>>>    	},
>>> +	{ do_sanitize, -1,
>>> +	  "sanitize", "<device>\n"
>>> +		"Send Sanitize command to the <device>.\nThis will delete the unmapped memory region of the device",
>>> +	  NULL
>>> +	},
>>>    	{ 0, 0, 0, 0 }
>>>    };
>>>    diff --git a/mmc.h b/mmc.h
>>> index c863751..5173d34 100644
>>> --- a/mmc.h
>>> +++ b/mmc.h
>>> @@ -38,6 +38,7 @@
>>>    #define EXT_CSD_PART_CONFIG		179
>>>    #define EXT_CSD_BOOT_WP			173
>>>    #define EXT_CSD_WR_REL_PARAM		166
>>> +#define EXT_CSD_SANITIZE_START		165
>>>    #define EXT_CSD_BKOPS_EN		163	/* R/W */
>>>    #define EXT_CSD_RST_N_FUNCTION		162	/* R/W */
>>>    #define EXT_CSD_NATIVE_SECTOR_SIZE	63 /* R */
>>> diff --git a/mmc_cmds.c b/mmc_cmds.c
>>> index b407f65..5473a20 100644
>>> --- a/mmc_cmds.c
>>> +++ b/mmc_cmds.c
>>> @@ -767,3 +767,31 @@ int do_read_extcsd(int nargs, char **argv)
>>>    out_free:
>>>    	return ret;
>>>    }
>>> +
>>> +int do_sanitize(int nargs, char **argv)
>>> +{
>>> +	int fd, ret;
>>> +	char *device;
>>> +
>>> +	CHECK(nargs != 2, "Usage: mmc sanitize </path/to/mmcblkX>\n",
>>> +			exit(1));
>>> +
>>> +	device = argv[1];
>>> +
>>> +	fd = open(device, O_RDWR);
>>> +	if (fd < 0) {
>>> +		perror("open");
>>> +		exit(1);
>>> +	}
>>> +
>>> +	ret = write_extcsd_value(fd, EXT_CSD_SANITIZE_START, 1);
>>> +	if (ret) {
>>> +		fprintf(stderr, "Could not write 0x%02x to EXT_CSD[%d] in %s\n",
>>> +			1, EXT_CSD_SANITIZE_START, device);
>>> +		exit(1);
>>> +	}
>>> +
>> don't we need to close the opened blkdev file here? or is it done
>> somewhere else?
> Linux closes open file descriptors on process exit, no?
ok then it looks good to me.

Acked-by: Subhash Jadavani <subhashj@codeaurora.org>

Thanks,
Subhash
>
> - Chris.