Re: [PATCH] Add method for triggering Sanitize command

[Chris Ball <cjb@laptop.org>]

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?

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child