[PATCH v2] cmd: mtd: check if a block has to be skipped or erased

[PATCH v2] cmd: mtd: check if a block has to be skipped or erased

[Dario Binacchi]

From: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>

As reported by patch [1], the `mtd erase' command should not erase bad
blocks.
To force bad block erasing you have to use the `mtd erase.dontskipbad'
command.

This patch tries to fix the same issue without modifying code taken
from the linux kernel, in order to make further upgrades easier.

[1] https://lore.kernel.org/all/20221006031501.110290-2-mikhail.kshevetskiy@iopsys.eu/
Suggested-by: Michael Trimarchi <michael@amarulasolutions.com>
Co-developed-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Co-developed-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Tested-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>

---

Changes in v2:
- Change the commit author
- Do not continue to erase if scrub option is enabled and a bad block
  was found but return from the function.
- Update the patch tags.

 cmd/mtd.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/cmd/mtd.c b/cmd/mtd.c
index ad5cc9827d55..a314745e95e1 100644
--- a/cmd/mtd.c
+++ b/cmd/mtd.c
@@ -434,11 +434,24 @@ static int do_mtd_erase(struct cmd_tbl *cmdtp, int flag, int argc,
 	erase_op.mtd = mtd;
 	erase_op.addr = off;
 	erase_op.len = mtd->erasesize;
-	erase_op.scrub = scrub;
 
 	while (len) {
-		ret = mtd_erase(mtd, &erase_op);
+		if (!scrub) {
+			ret = mtd_block_isbad(mtd, erase_op.addr);
+			if (ret < 0) {
+				printf("Failed to get bad block at 0x%08llx\n",
+				       erase_op.addr);
+				ret = CMD_RET_FAILURE;
+				goto out_put_mtd;
+			} else if (ret > 0) {
+				/* simulate bad block behavior */
+				ret = -EIO;
+				goto skip_block_erasing;
+			}
+		}
 
+		ret = mtd_erase(mtd, &erase_op);
+skip_block_erasing:
 		if (ret) {
 			/* Abort if its not a bad block error */
 			if (ret != -EIO)
-- 
2.32.0

Re: [PATCH v2] cmd: mtd: check if a block has to be skipped or erased

[Mikhail Kshevetskiy]

What patch will be finally applied? I am preparing a patch that will 
fix Dario Binacchi issues with non-BBT bad block.

From my point of view this patch have wrong lines in 'Changes in v2'
- Do not continue to erase if scrub option is enabled and a bad block
  was found but return from the function.

Issues of original Dario Binacchi patch:

Non-BBT registered bad block will break 'mtd erase'.

In this case
 * mtd_erase() will returns with -EIO
 * erasing will be stopped due to error
 * 'mtd erase' returns CMD_RET_SUCCESS as -EIO is expected result

Fix this by:
  a) return back -EIO check after mtd_erase()
  b) simulate bad block behavior and jump to mtd_erase() results
     check in the case of BBT registered bad block.



On 24.10.2022 12:35, Dario Binacchi wrote:
> [External email]
>
>
>
>
>
> From: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
>
> As reported by patch [1], the `mtd erase' command should not erase bad
> blocks.
> To force bad block erasing you have to use the `mtd erase.dontskipbad'
> command.
>
> This patch tries to fix the same issue without modifying code taken
> from the linux kernel, in order to make further upgrades easier.
>
> [1] https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Fall%2F20221006031501.110290-2-mikhail.kshevetskiy%40iopsys.eu%2F&amp;data=05%7C01%7Cmikhail.kshevetskiy%40iopsys.eu%7C0b0682eb6b3444494b7b08dab5a31581%7C7ff78d652de440f586750569e5c7a65d%7C0%7C0%7C638022009312464027%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=7Mx%2BHk7KIxaUitavWhTRwtfDL%2FaaOYA9o02oWFiFlw0%3D&amp;reserved=0
> Suggested-by: Michael Trimarchi <michael@amarulasolutions.com>
> Co-developed-by: Michael Trimarchi <michael@amarulasolutions.com>
> Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
> Co-developed-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> Tested-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
> Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
>
> ---
>
> Changes in v2:
> - Change the commit author
> - Do not continue to erase if scrub option is enabled and a bad block
>   was found but return from the function.
> - Update the patch tags.
>
>  cmd/mtd.c | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
>
> diff --git a/cmd/mtd.c b/cmd/mtd.c
> index ad5cc9827d55..a314745e95e1 100644
> --- a/cmd/mtd.c
> +++ b/cmd/mtd.c
> @@ -434,11 +434,24 @@ static int do_mtd_erase(struct cmd_tbl *cmdtp, int flag, int argc,
>         erase_op.mtd = mtd;
>         erase_op.addr = off;
>         erase_op.len = mtd->erasesize;
> -       erase_op.scrub = scrub;
>
>         while (len) {
> -               ret = mtd_erase(mtd, &erase_op);
> +               if (!scrub) {
> +                       ret = mtd_block_isbad(mtd, erase_op.addr);
> +                       if (ret < 0) {
> +                               printf("Failed to get bad block at 0x%08llx\n",
> +                                      erase_op.addr);
> +                               ret = CMD_RET_FAILURE;
> +                               goto out_put_mtd;
> +                       } else if (ret > 0) {
> +                               /* simulate bad block behavior */
> +                               ret = -EIO;
> +                               goto skip_block_erasing;
> +                       }
> +               }
>
> +               ret = mtd_erase(mtd, &erase_op);
> +skip_block_erasing:
>                 if (ret) {
>                         /* Abort if its not a bad block error */
>                         if (ret != -EIO)
> --
> 2.32.0
>

Re: [PATCH v2] cmd: mtd: check if a block has to be skipped or erased

[Simon Glass]

Hi,

On Mon, 24 Oct 2022 at 03:35, Dario Binacchi
<dario.binacchi@amarulasolutions.com> wrote:
>
> From: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
>
> As reported by patch [1], the `mtd erase' command should not erase bad
> blocks.
> To force bad block erasing you have to use the `mtd erase.dontskipbad'
> command.
>
> This patch tries to fix the same issue without modifying code taken
> from the linux kernel, in order to make further upgrades easier.
>
> [1] https://lore.kernel.org/all/20221006031501.110290-2-mikhail.kshevetskiy@iopsys.eu/
> Suggested-by: Michael Trimarchi <michael@amarulasolutions.com>
> Co-developed-by: Michael Trimarchi <michael@amarulasolutions.com>
> Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
> Co-developed-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> Tested-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
> Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
>
> ---
>
> Changes in v2:
> - Change the commit author
> - Do not continue to erase if scrub option is enabled and a bad block
>   was found but return from the function.
> - Update the patch tags.
>
>  cmd/mtd.c | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)

Can we get some tests in test/dm/mtd.c?

Regards,
Simon

Re: [PATCH v2] cmd: mtd: check if a block has to be skipped or erased

[Dario Binacchi]

Hi Simon,

On Wed, Oct 26, 2022 at 1:35 AM Simon Glass <sjg@chromium.org> wrote:
>
> Hi,
>
> On Mon, 24 Oct 2022 at 03:35, Dario Binacchi
> <dario.binacchi@amarulasolutions.com> wrote:
> >
> > From: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
> >
> > As reported by patch [1], the `mtd erase' command should not erase bad
> > blocks.
> > To force bad block erasing you have to use the `mtd erase.dontskipbad'
> > command.
> >
> > This patch tries to fix the same issue without modifying code taken
> > from the linux kernel, in order to make further upgrades easier.
> >
> > [1] https://lore.kernel.org/all/20221006031501.110290-2-mikhail.kshevetskiy@iopsys.eu/
> > Suggested-by: Michael Trimarchi <michael@amarulasolutions.com>
> > Co-developed-by: Michael Trimarchi <michael@amarulasolutions.com>
> > Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
> > Co-developed-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> > Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> > Tested-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
> > Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
> >
> > ---
> >
> > Changes in v2:
> > - Change the commit author
> > - Do not continue to erase if scrub option is enabled and a bad block
> >   was found but return from the function.
> > - Update the patch tags.
> >
> >  cmd/mtd.c | 17 +++++++++++++++--
> >  1 file changed, 15 insertions(+), 2 deletions(-)
>
> Can we get some tests in test/dm/mtd.c?

We are thinking about it. Probably not soon, but we are thinking
about what and how to add them.

Thanks and regards,
Dario

>
> Regards,
> Simon



-- 

Dario Binacchi

Embedded Linux Developer

dario.binacchi@amarulasolutions.com

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