2007-11-08 08:24:20

by Roopesh

[permalink] [raw]
Subject: MMC/SD: Write operation in invalid states by borken cards.

Hi,

If a write operation fails, shouldnt we still check for the card
state to be 'ready to accept next data'?

This question is because I have noticed that some (broken) cards
fail the write command, and the immediately issued subsequent
commands also fail since the card state was never checked before
sending these commands.
(There was a discussion about these cards at the thread: "MMC:
CRC Errors with 2GB cards)

diff -a -u -p -r1.2 block.c
--- drivers/mmc/card/block.c 22 Oct 2007 10:39:44 -0000 1.2
+++ drivers/mmc/card/block.c 8 Nov 2007 06:55:37 -0000
@@ -206,6 +206,7 @@ static int mmc_blk_issue_rq(struct mmc_q
struct mmc_card *card = md->queue.card;
struct mmc_blk_request brq;
int ret = 1, sg_pos, data_size;
+ int data_error = 0;

mmc_claim_host(card->host);

@@ -282,19 +283,19 @@ static int mmc_blk_issue_rq(struct mmc_q
if (brq.cmd.error) {
printk(KERN_ERR "%s: error %d sending read/write command\n",
req->rq_disk->disk_name, brq.cmd.error);
- goto cmd_err;
+ data_error = 1;
}

if (brq.data.error) {
printk(KERN_ERR "%s: error %d transferring data\n",
req->rq_disk->disk_name, brq.data.error);
- goto cmd_err;
+ data_error = 1;
}

if (brq.stop.error) {
printk(KERN_ERR "%s: error %d sending stop command\n",
req->rq_disk->disk_name, brq.stop.error);
- goto cmd_err;
+ data_error = 1;
}

if (rq_data_dir(req) != READ) {
@@ -320,6 +321,9 @@ static int mmc_blk_issue_rq(struct mmc_q
goto cmd_err;
#endif
}
+
+ if (data_error == 1)
+ goto cmd_err;

/*
* A block was successfully transferred.


Thanks,
Roopesh.


2007-11-10 10:51:33

by Pierre Ossman

[permalink] [raw]
Subject: Re: MMC/SD: Write operation in invalid states by borken cards.

On Thu, 8 Nov 2007 03:24:10 -0500
Roopesh <[email protected]> wrote:

> Hi,
>
> If a write operation fails, shouldnt we still check for the card
> state to be 'ready to accept next data'?
>
> This question is because I have noticed that some (broken) cards
> fail the write command, and the immediately issued subsequent
> commands also fail since the card state was never checked before
> sending these commands.
> (There was a discussion about these cards at the thread: "MMC:
> CRC Errors with 2GB cards)
>

I'm confused. Didn't the previous fix solve your problems?

Rgds
--
-- Pierre Ossman

Linux kernel, MMC maintainer http://www.kernel.org
PulseAudio, core developer http://pulseaudio.org
rdesktop, core developer http://www.rdesktop.org

2007-11-23 10:27:36

by Roopesh

[permalink] [raw]
Subject: Re: MMC/SD: Write operation in invalid states by borken cards.

:---------- Original Message ----------
:
:From: Pierre Ossman [[email protected]]
:To : To Roopesh
:Sub : Re: MMC/SD: Write operation in invalid states by borken cards.
:Sent: Sat, Nov 10, 2007 at 05:51:19AM EST

: On Thu, 8 Nov 2007 03:24:10 -0500
: Roopesh <[email protected]> wrote:
:
: > Hi,
: >
: > If a write operation fails, shouldnt we still check for the card
: > state to be 'ready to accept next data'?
: >
: > This question is because I have noticed that some (broken) cards
: > fail the write command, and the immediately issued subsequent
: > commands also fail since the card state was never checked before
: > sending these commands.
: > (There was a discussion about these cards at the thread: "MMC:
: > CRC Errors with 2GB cards)
: >
:
: I'm confused. Didn't the previous fix solve your problems?

I am sorry I couldnt respond in time, and also for creating the
confusion. The previous fix did solve my problem. However, if
for some other reason the card goes into an invalid state and a
write command fails, shouldnt we still check for the card state
before sending the next IO command?

: Rgds
: --
: -- Pierre Ossman
:
: Linux kernel, MMC maintainer http://www.kernel.org
: PulseAudio, core developer http://pulseaudio.org
: rdesktop, core developer http://www.rdesktop.org