linux-kernel - Re: [PATCH] mmc: check EXT_CSD_PARTITION_SETTING

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Message-ID: <53EB2DC3.2080002@neotion.com>
Date:	Wed, 13 Aug 2014 11:20:03 +0200
From:	Grégory Soutadé <gsoutade@...tion.com>
To:	Ulf Hansson <ulf.hansson@...aro.org>
CC:	Chris Ball <chris@...ntf.net>,
	Seungwon Jeon <tgih.jun@...sung.com>,
	Jaehoon Chung <jh80.chung@...sung.com>,
	linux-mmc <linux-mmc@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] mmc: check EXT_CSD_PARTITION_SETTING_COMPLETED before
 creating partitions

Le 13/08/2014 10:36, Ulf Hansson a écrit :
> On 17 July 2014 16:57, Grégory Soutadé <gsoutade@...tion.com> wrote:
>> Create MMC general purpose partitions only if
>> EXT_CSD_PARTITION_SETTING_COMPLETED bit is set.
>> Some tools may set general purpose partition size(s) but fail or stop
>> without finalize.
>> Another case is to set invalid partition size(s).
>>
>> Signed-off-by: Grégory Soutadé <gsoutade@...tion.com>
>> ---
>>  drivers/mmc/core/mmc.c  |   15 +++++++++++----
>>  include/linux/mmc/mmc.h |    2 ++
>>  2 files changed, 13 insertions(+), 4 deletions(-)
>>
>> From commit b6603fe574af289dbe9eb9fb4c540bca04f5a053 in master linux tree.
>>
>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
>> index 793c6f7..b9fe211 100644
>> --- a/drivers/mmc/core/mmc.c
>> +++ b/drivers/mmc/core/mmc.c
>> @@ -471,10 +471,17 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
>>                                 ext_csd[EXT_CSD_GP_SIZE_MULT + idx * 3];
>>                                 part_size *= (size_t)(hc_erase_grp_sz *
>>                                         hc_wp_grp_sz);
>> -                               mmc_part_add(card, part_size << 19,
>> -                                       EXT_CSD_PART_CONFIG_ACC_GP0 + idx,
>> -                                       "gp%d", idx, false,
>> -                                       MMC_BLK_DATA_AREA_GP);
>> +                               if (ext_csd[EXT_CSD_PARTITION_SETTING_COMPLETED] &
>> +                               EXT_CSD_PART_SETTING_COMPLETED) {
> 
> Some minor comments here.
> 
> I think you could move this if statement up and into the previous "if"
> where we check for "ext_csd[EXT_CSD_PARTITION_SUPPORT] &
> EXT_CSD_PART_SUPPORT_PART_EN".
> 
> Additionally, please run checkpatch.
> 
> Kind regards
> Uffe

Hello,

I didn't put the if statement above to warn user in case of bad partitioning.
I don't want the kernel to silently ignore this error.

checkpatch has been run before sending this patch, I know there are two lines
with two extra characters, but names used here are quite long. I hope it will
not block upstream inclusion.


Best regards
Grégory Soutadé

> 
>> +                                       mmc_part_add(card, part_size << 19,
>> +                                               EXT_CSD_PART_CONFIG_ACC_GP0 + idx,
>> +                                               "gp%d", idx, false,
>> +                                               MMC_BLK_DATA_AREA_GP);
>> +                               } else {
>> +                                       pr_warn("%s: has partition size defined, but setting is not complete\n",
>> +                                               mmc_hostname(card->host));
>> +                                       break;
>> +                               }
>>                         }
>>                 }
>>                 card->ext_csd.sec_trim_mult =
>> diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
>> index 64ec963..78753bc 100644
>> --- a/include/linux/mmc/mmc.h
>> +++ b/include/linux/mmc/mmc.h
>> @@ -281,6 +281,7 @@ struct _mmc_csd {
>>  #define EXT_CSD_EXP_EVENTS_CTRL                56      /* R/W, 2 bytes */
>>  #define EXT_CSD_DATA_SECTOR_SIZE       61      /* R */
>>  #define EXT_CSD_GP_SIZE_MULT           143     /* R/W */
>> +#define EXT_CSD_PARTITION_SETTING_COMPLETED 155        /* R/W */
>>  #define EXT_CSD_PARTITION_ATTRIBUTE    156     /* R/W */
>>  #define EXT_CSD_PARTITION_SUPPORT      160     /* RO */
>>  #define EXT_CSD_HPI_MGMT               161     /* R/W */
>> @@ -349,6 +350,7 @@ struct _mmc_csd {
>>  #define EXT_CSD_PART_CONFIG_ACC_RPMB   (0x3)
>>  #define EXT_CSD_PART_CONFIG_ACC_GP0    (0x4)
>>
>> +#define EXT_CSD_PART_SETTING_COMPLETED (0x1)
>>  #define EXT_CSD_PART_SUPPORT_PART_EN   (0x1)
>>
>>  #define EXT_CSD_CMD_SET_NORMAL         (1<<0)
>> --
>> 1.7.0.4
> 


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