[PATCH] MMC: fix the use of kunmap_atomic() in tmio_mmc.h

[PATCH] MMC: fix the use of kunmap_atomic() in tmio_mmc.h

[Guennadi Liakhovetski]

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mmc/host/tmio_mmc.c |    7 ++++---
 drivers/mmc/host/tmio_mmc.h |    8 +++-----
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index ee7d0a5..69d98e3 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -164,6 +164,7 @@ tmio_mmc_start_command(struct tmio_mmc_host *host, struct mmc_command *cmd)
 static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 {
 	struct mmc_data *data = host->data;
+	void *sg_virt;
 	unsigned short *buf;
 	unsigned int count;
 	unsigned long flags;
@@ -173,8 +174,8 @@ static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 		return;
 	}
 
-	buf = (unsigned short *)(tmio_mmc_kmap_atomic(host, &flags) +
-	      host->sg_off);
+	sg_virt = tmio_mmc_kmap_atomic(host->sg_ptr, &flags);
+	buf = (unsigned short *)(sg_virt + host->sg_off);
 
 	count = host->sg_ptr->length - host->sg_off;
 	if (count > data->blksz)
@@ -191,7 +192,7 @@ static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
 
 	host->sg_off += count;
 
-	tmio_mmc_kunmap_atomic(host, &flags);
+	tmio_mmc_kunmap_atomic(sg_virt, &flags);
 
 	if (host->sg_off == host->sg_ptr->length)
 		tmio_mmc_next_sg(host);
diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
index 64f7d5d..446f9e9 100644
--- a/drivers/mmc/host/tmio_mmc.h
+++ b/drivers/mmc/host/tmio_mmc.h
@@ -177,19 +177,17 @@ static inline int tmio_mmc_next_sg(struct tmio_mmc_host *host)
 	return --host->sg_len;
 }
 
-static inline char *tmio_mmc_kmap_atomic(struct tmio_mmc_host *host,
+static inline char *tmio_mmc_kmap_atomic(struct scatterlist *sg,
 	unsigned long *flags)
 {
-	struct scatterlist *sg = host->sg_ptr;
-
 	local_irq_save(*flags);
 	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
 }
 
-static inline void tmio_mmc_kunmap_atomic(struct tmio_mmc_host *host,
+static inline void tmio_mmc_kunmap_atomic(void *virt,
 	unsigned long *flags)
 {
-	kunmap_atomic(sg_page(host->sg_ptr), KM_BIO_SRC_IRQ);
+	kunmap_atomic(virt, KM_BIO_SRC_IRQ);
 	local_irq_restore(*flags);
 }
 
-- 
1.7.2

Re: [PATCH] MMC: fix the use of kunmap_atomic() in tmio_mmc.h

[Eric Miao]

On Sun, Aug 15, 2010 at 4:29 AM, Guennadi Liakhovetski
<g.liakhovetski@gmx.de> wrote:
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

If I understand the kunmap_atomic() thing correctly, this looks good to me.

Acked-by: Eric Miao <eric.y.miao@gmail.com>


> ---
>  drivers/mmc/host/tmio_mmc.c |    7 ++++---
>  drivers/mmc/host/tmio_mmc.h |    8 +++-----
>  2 files changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
> index ee7d0a5..69d98e3 100644
> --- a/drivers/mmc/host/tmio_mmc.c
> +++ b/drivers/mmc/host/tmio_mmc.c
> @@ -164,6 +164,7 @@ tmio_mmc_start_command(struct tmio_mmc_host *host, struct mmc_command *cmd)
>  static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
>  {
>        struct mmc_data *data = host->data;
> +       void *sg_virt;
>        unsigned short *buf;
>        unsigned int count;
>        unsigned long flags;
> @@ -173,8 +174,8 @@ static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
>                return;
>        }
>
> -       buf = (unsigned short *)(tmio_mmc_kmap_atomic(host, &flags) +
> -             host->sg_off);
> +       sg_virt = tmio_mmc_kmap_atomic(host->sg_ptr, &flags);
> +       buf = (unsigned short *)(sg_virt + host->sg_off);
>
>        count = host->sg_ptr->length - host->sg_off;
>        if (count > data->blksz)
> @@ -191,7 +192,7 @@ static void tmio_mmc_pio_irq(struct tmio_mmc_host *host)
>
>        host->sg_off += count;
>
> -       tmio_mmc_kunmap_atomic(host, &flags);
> +       tmio_mmc_kunmap_atomic(sg_virt, &flags);
>
>        if (host->sg_off == host->sg_ptr->length)
>                tmio_mmc_next_sg(host);
> diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
> index 64f7d5d..446f9e9 100644
> --- a/drivers/mmc/host/tmio_mmc.h
> +++ b/drivers/mmc/host/tmio_mmc.h
> @@ -177,19 +177,17 @@ static inline int tmio_mmc_next_sg(struct tmio_mmc_host *host)
>        return --host->sg_len;
>  }
>
> -static inline char *tmio_mmc_kmap_atomic(struct tmio_mmc_host *host,
> +static inline char *tmio_mmc_kmap_atomic(struct scatterlist *sg,
>        unsigned long *flags)
>  {
> -       struct scatterlist *sg = host->sg_ptr;
> -
>        local_irq_save(*flags);
>        return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
>  }
>
> -static inline void tmio_mmc_kunmap_atomic(struct tmio_mmc_host *host,
> +static inline void tmio_mmc_kunmap_atomic(void *virt,
>        unsigned long *flags)
>  {
> -       kunmap_atomic(sg_page(host->sg_ptr), KM_BIO_SRC_IRQ);
> +       kunmap_atomic(virt, KM_BIO_SRC_IRQ);
>        local_irq_restore(*flags);
>  }
>
> --
> 1.7.2
>
>

Re: [PATCH] MMC: fix the use of kunmap_atomic() in tmio_mmc.h

[Magnus Damm]

On Sun, Aug 15, 2010 at 5:29 AM, Guennadi Liakhovetski
<g.liakhovetski@gmx.de> wrote:
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
>  drivers/mmc/host/tmio_mmc.c |    7 ++++---
>  drivers/mmc/host/tmio_mmc.h |    8 +++-----
>  2 files changed, 7 insertions(+), 8 deletions(-)

I just used this patch with latest linux-2.6 git to fix the tmio_mmc
compile error.  Some light testing on AP4EVB with insmod and rmmod
(and Runtime PM) worked just fine. Thanks!

Tested-by: Magnus Damm <damm@opensource.se>

Re: [PATCH] MMC: fix the use of kunmap_atomic() in tmio_mmc.h

[Andrew Morton]

On Sat, 14 Aug 2010 22:29:40 +0200 (CEST)
Guennadi Liakhovetski <g.liakhovetski@gmx.de> wrote:

> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

No changelog :(

- what was wrong with the old code?

- how did the patch fix it?

Re: [PATCH] MMC: fix the use of kunmap_atomic() in tmio_mmc.h

[Guennadi Liakhovetski]

Hi Andrew

On Thu, 26 Aug 2010, Andrew Morton wrote:

> On Sat, 14 Aug 2010 22:29:40 +0200 (CEST)
> Guennadi Liakhovetski <g.liakhovetski@gmx.de> wrote:
> 
> > Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> 
> No changelog :(

Sorry, I thought this was one of the cases, where the subject says it all.

> - what was wrong with the old code?
> 
> - how did the patch fix it?

How about:

kunmap_atomic() takes the cookie, returned by the kmap_atomic() as its 
argument and not the page address, used as an argument to kmap_atomic(). 
This patch fixes the compile error:

In file included from /opt/src/linux-2.6/drivers/mmc/host/tmio_mmc.c:37:
/opt/src/linux-2.6/drivers/mmc/host/tmio_mmc.h: In function 'tmio_mmc_kunmap_atomic':
/opt/src/linux-2.6/drivers/mmc/host/tmio_mmc.h:192: error: negative width in bit-field '<anonymous>'

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/