Hi
On Tue, Sep 28, 2010 at 2:51 PM, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
> On 27/09/10 06:32, Ethan Du wrote:
>>
>> The while loop when handling rw request may become deadloop in
>> case of bad card
>> I've seen mmcqd gets blocked forever after a single error message:
>>
>> mmcblk0: error -110 sending read/write command, response 0x900, card
>> status 0x80e00
>>
>> Also there was case of card reports status without error
>>
>> mmcblk0: error -110 sending read/write command, response 0x900, card
>> status 0xe00
>>
>> After this error, the card can stay in prg state, and never comes
>> back,
>> and may not report any error further. So a break out condition
>> should be set in mmc block layer:
>> * should not enter the waiting loop in case of error
>
> How do you know there are not any errors where you do need to wait?
Would you enumerate an example?
I am not sure all hosts, seem most host controllers already wait
enough time before return to block layer when cmd->flags has
MMC_RSP_BUSY
>
>> * should break out from the waiting loop, if card response with error
>> * should break out from the waiting loop when timeout
>>
>> These will not help with the card, one more thing to do:
>> * re-init the card in case of too many errors
>
> Using mmc_detect_change() will give you a new block device.
> That is probably a bad idea for a non-removable card. Also
Yes, figured it is better to do something like host resume.
I made a function mmc_reinit_host(), will send out the patch
> if the reinitialization is going to help, then why wait for
> lots of errors before doing it.
With the hope that, card can still work after this error
>
>>
>> Signed-off-by: Ethan Du<ethan.too@xxxxxxxxx>
>> ---
>> drivers/mmc/card/block.c | 35 +++++++++++++++++++++++++++--------
>> drivers/mmc/core/mmc.c | 9 +++++++--
>> drivers/mmc/core/sd.c | 8 ++++++--
>> include/linux/mmc/card.h | 3 +++
>> include/linux/mmc/mmc.h | 1 +
>> 5 files changed, 44 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
>> index d545f79..1d304a2 100644
>> --- a/drivers/mmc/card/block.c
>> +++ b/drivers/mmc/card/block.c
>> @@ -316,12 +316,14 @@ out:
>> return err ? 0 : 1;
>> }
>>
>> +#define BUSY_TIMEOUT_MS (16 * 1024)
>> static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
>> {
>> struct mmc_blk_data *md = mq->data;
>> struct mmc_card *card = md->queue.card;
>> struct mmc_blk_request brq;
>> int ret = 1, disable_multi = 0;
>> + unsigned long timeout = 0;
>>
>> mmc_claim_host(card->host);
>>
>> @@ -453,7 +455,9 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
>> *mq, struct request *req)
>> brq.stop.resp[0], status);
>> }
>>
>> - if (!mmc_host_is_spi(card->host)&& rq_data_dir(req) !=
>> READ) {
>> + if (!mmc_host_is_spi(card->host)&& rq_data_dir(req) !=
>> READ&&
>> + !brq.cmd.error&& !brq.data.error&& !brq.stop.error)
>> {
>> + timeout = jiffies +
>> msecs_to_jiffies(BUSY_TIMEOUT_MS);
>> do {
>> int err;
>>
>> @@ -466,13 +470,22 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
>> *mq, struct request *req)
>> req->rq_disk->disk_name,
>> err);
>> goto cmd_err;
>> }
>> + if (cmd.resp[0]& R1_ERROR_MASK) {
>> + printk(KERN_ERR "%s: card err
>> %#x\n",
>> + req->rq_disk->disk_name,
>> + cmd.resp[0]);
>> + goto cmd_err;
>> + }
>> /*
>> * Some cards mishandle the status bits,
>> * so make sure to check both the busy
>> * indication and the card state.
>> */
>> - } while (!(cmd.resp[0]& R1_READY_FOR_DATA) ||
>> - (R1_CURRENT_STATE(cmd.resp[0]) == 7));
>> + if ((cmd.resp[0]& R1_READY_FOR_DATA)&&
>> + (R1_CURRENT_STATE(cmd.resp[0]) != 7))
>> + break;
>> + } while (time_before(jiffies, timeout));
>> + /* Ignore timeout out */
>>
>> #if 0
>> if (cmd.resp[0]& ~0x00000900)
>> @@ -510,11 +523,11 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
>> *mq, struct request *req)
>>
>> return 1;
>>
>> - cmd_err:
>> - /*
>> - * If this is an SD card and we're writing, we can first
>> - * mark the known good sectors as ok.
>> - *
>> +cmd_err:
>> + /*
>> + * If this is an SD card and we're writing, we can first
>> + * mark the known good sectors as ok.
>> + *
>> * If the card is not SD, we can still ok written sectors
>> * as reported by the controller (which might be less than
>> * the real number of written sectors, but never more).
>> @@ -541,6 +554,12 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue
>> *mq, struct request *req)
>> ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
>> spin_unlock_irq(&md->lock);
>>
>> + card->err_count++;
>> + if (card->err_count>= ERR_TRIGGER_REINIT) {
>> + printk(KERN_WARNING "%s: re-init the card due to error\n",
>> + req->rq_disk->disk_name);
>> + mmc_detect_change(card->host, 0);
>> + }
>> return 0;
>> }
>>
>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
>> index 6909a54..79c4759 100644
>> --- a/drivers/mmc/core/mmc.c
>> +++ b/drivers/mmc/core/mmc.c
>> @@ -535,6 +535,8 @@ static int mmc_init_card(struct mmc_host *host, u32
>> ocr,
>>
>> if (!oldcard)
>> host->card = card;
>> + else
>> + oldcard->err_count = 0;
>>
>> return 0;
>>
>> @@ -563,17 +565,20 @@ static void mmc_remove(struct mmc_host *host)
>> */
>> static void mmc_detect(struct mmc_host *host)
>> {
>> - int err;
>> + int err = 0;
>>
>> BUG_ON(!host);
>> BUG_ON(!host->card);
>>
>> mmc_claim_host(host);
>>
>> + if (host->card->err_count>= ERR_TRIGGER_REINIT)
>> + err = mmc_init_card(host, host->ocr, host->card);
>> /*
>> * Just check if our card has been removed.
>> */
>> - err = mmc_send_status(host->card, NULL);
>> + if (!err)
>> + err = mmc_send_status(host->card, NULL);
>>
>> mmc_release_host(host);
>>
>> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
>> index 0f52410..820b0d1 100644
>> --- a/drivers/mmc/core/sd.c
>> +++ b/drivers/mmc/core/sd.c
>> @@ -635,6 +635,7 @@ static int mmc_sd_init_card(struct mmc_host *host, u32
>> ocr,
>> mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
>> }
>>
>> + card->err_count = 0;
>> host->card = card;
>> return 0;
>>
>> @@ -662,17 +663,20 @@ static void mmc_sd_remove(struct mmc_host *host)
>> */
>> static void mmc_sd_detect(struct mmc_host *host)
>> {
>> - int err;
>> + int err = 0;
>>
>> BUG_ON(!host);
>> BUG_ON(!host->card);
>>
>> mmc_claim_host(host);
>>
>> + if (host->card->err_count>= ERR_TRIGGER_REINIT)
>> + err = mmc_sd_init_card(host, host->ocr, host->card);
>> /*
>> * Just check if our card has been removed.
>> */
>> - err = mmc_send_status(host->card, NULL);
>> + if (!err)
>> + err = mmc_send_status(host->card, NULL);
>>
>> mmc_release_host(host);
>>
>> diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
>> index 6b75250..178de17 100644
>> --- a/include/linux/mmc/card.h
>> +++ b/include/linux/mmc/card.h
>> @@ -143,6 +143,9 @@ struct mmc_card {
>> const char **info; /* info strings */
>> struct sdio_func_tuple *tuples; /* unknown common tuples */
>>
>> + unsigned int err_count;
>> +#define ERR_TRIGGER_REINIT 1024
>> +
>> struct dentry *debugfs_root;
>> };
>>
>> diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
>> index dd11ae5..3b979a1 100644
>> --- a/include/linux/mmc/mmc.h
>> +++ b/include/linux/mmc/mmc.h
>> @@ -122,6 +122,7 @@
>> #define R1_UNDERRUN (1<< 18) /* ex, c */
>> #define R1_OVERRUN (1<< 17) /* ex, c */
>> #define R1_CID_CSD_OVERWRITE (1<< 16) /* erx, c, CID/CSD
>> overwrite */
>> +#define R1_ERROR_MASK 0xffff0000
>> #define R1_WP_ERASE_SKIP (1<< 15) /* sx, c */
>> #define R1_CARD_ECC_DISABLED (1<< 14) /* sx, a */
>> #define R1_ERASE_RESET (1<< 13) /* sr, c */
>
>
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