Message ID | 20210824191726.8296-1-nishadkamdar@gmail.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | [v4] mmc: core: Return correct emmc response in case of ioctl error | expand |
On Tue, 24 Aug 2021 at 21:17, Nishad Kamdar <nishadkamdar@gmail.com> wrote: > > When a read/write command is sent via ioctl to the kernel, > and the command fails, the actual error response of the emmc > is not sent to the user. > > IOCTL read/write tests are carried out using commands > 17 (Single BLock Read), 24 (Single Block Write), > 18 (Multi Block Read), 25 (Multi Block Write) > > The tests are carried out on a 64Gb emmc device. All of these > tests try to access an "out of range" sector address (0x09B2FFFF). > > It is seen that without the patch the response received by the user > is not OUT_OF_RANGE error (R1 response 31st bit is not set) as per > JEDEC specification. After applying the patch proper response is seen. > This is because the function returns without copying the response to > the user in case of failure. This patch fixes the issue. > > Hence, this memcpy is required whether we get an error response or not. > Therefor it is moved up from the current position up to immediately > after we have called mmc_wait_for_req(). > > The test code and the output of only the CMD17 is included in the > commit to limit the message length. > > CMD17 (Test Code Snippet): > ========================== > printf("Forming CMD%d\n", opt_idx); > /* single block read */ > cmd.blksz = 512; > cmd.blocks = 1; > cmd.write_flag = 0; > cmd.opcode = 17; > //cmd.arg = atoi(argv[3]); > cmd.arg = 0x09B2FFFF; > /* Expecting response R1B */ > cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC; > > memset(data, 0, sizeof(__u8) * 512); > mmc_ioc_cmd_set_data(cmd, data); > > printf("Sending CMD%d: ARG[0x%08x]\n", opt_idx, cmd.arg); > if(ioctl(fd, MMC_IOC_CMD, &cmd)) > perror("Error"); > > printf("\nResponse: %08x\n", cmd.response[0]); > > CMD17 (Output without patch): > ============================= > test@test-LIVA-Z:~$ sudo ./mmc cmd_test /dev/mmcblk0 17 > Entering the do_mmc_commands:Device: /dev/mmcblk0 nargs:4 > Entering the do_mmc_commands:Device: /dev/mmcblk0 options[17, 0x09B2FFF] > Forming CMD17 > Sending CMD17: ARG[0x09b2ffff] > Error: Connection timed out > > Response: 00000000 > (Incorrect response) > > CMD17 (Output with patch): > ========================== > test@test-LIVA-Z:~$ sudo ./mmc cmd_test /dev/mmcblk0 17 > [sudo] password for test: > Entering the do_mmc_commands:Device: /dev/mmcblk0 nargs:4 > Entering the do_mmc_commands:Device: /dev/mmcblk0 options[17, 09B2FFFF] > Forming CMD17 > Sending CMD17: ARG[0x09b2ffff] > Error: Connection timed out > > Response: 80000900 > (Correct OUT_OF_ERROR response as per JEDEC specification) > > Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com> > Reviewed-by: Avri Altman <avri.altman@wdc.com> Applied for next, thanks! Kind regards Uffe > --- > Changes in v4: > - Moved the existing > "memcpy(&(idata->ic.response), cmd.resp, sizeof(cmd.resp));" > from a couple of lines further down in the code, up to > immediately after we have called mmc_wait_for_req(). > - Modified the commit message to explain this change > Changes in v3: > - Shorten the commit message to include only CMD17 related > code and test. > Changes in v2: > - Make commit message clearer by adding test cases as outputs. > > drivers/mmc/core/block.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c > index 672cc505ce378..94bb8b4cd6a4e 100644 > --- a/drivers/mmc/core/block.c > +++ b/drivers/mmc/core/block.c > @@ -557,6 +557,7 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md, > return mmc_sanitize(card, idata->ic.cmd_timeout_ms); > > mmc_wait_for_req(card->host, &mrq); > + memcpy(&idata->ic.response, cmd.resp, sizeof(cmd.resp)); > > if (cmd.error) { > dev_err(mmc_dev(card->host), "%s: cmd error %d\n", > @@ -606,8 +607,6 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md, > if (idata->ic.postsleep_min_us) > usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us); > > - memcpy(&(idata->ic.response), cmd.resp, sizeof(cmd.resp)); > - > if (idata->rpmb || (cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B) { > /* > * Ensure RPMB/R1B command has completed by polling CMD13 > -- > 2.17.1 >
diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 672cc505ce378..94bb8b4cd6a4e 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -557,6 +557,7 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md, return mmc_sanitize(card, idata->ic.cmd_timeout_ms); mmc_wait_for_req(card->host, &mrq); + memcpy(&idata->ic.response, cmd.resp, sizeof(cmd.resp)); if (cmd.error) { dev_err(mmc_dev(card->host), "%s: cmd error %d\n", @@ -606,8 +607,6 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md, if (idata->ic.postsleep_min_us) usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us); - memcpy(&(idata->ic.response), cmd.resp, sizeof(cmd.resp)); - if (idata->rpmb || (cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B) { /* * Ensure RPMB/R1B command has completed by polling CMD13