2012-05-01 21:59:59

by Thomas Abraham

[permalink] [raw]
Subject: [PATCH] mmc: dw_mmc: make multiple instances of dw_mci_card_workqueue

The variable 'dw_mci_card_workqueue' is a global variable shared between
multiple instances of the dw_mmc host controller. Due to this, data
corruption has been noticed when multiple instances of dw_mmc controllers
are actively reading/writing the media. Fix this by adding a instance
of 'struct workqueue_struct' for each host instance and removing the
global 'dw_mci_card_workqueue' instance.

Signed-off-by: Thomas Abraham <[email protected]>
---
drivers/mmc/host/dw_mmc.c | 14 ++++++--------
include/linux/mmc/dw_mmc.h | 1 +
2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index ab3fc46..1532357 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -100,8 +100,6 @@ struct dw_mci_slot {
int last_detect_state;
};

-static struct workqueue_struct *dw_mci_card_workqueue;
-
#if defined(CONFIG_DEBUG_FS)
static int dw_mci_req_show(struct seq_file *s, void *v)
{
@@ -1605,7 +1603,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)

if (pending & SDMMC_INT_CD) {
mci_writel(host, RINTSTS, SDMMC_INT_CD);
- queue_work(dw_mci_card_workqueue, &host->card_work);
+ queue_work(host->card_workqueue, &host->card_work);
}

/* Handle SDIO Interrupts */
@@ -1844,7 +1842,7 @@ static int __init dw_mci_init_slot(struct dw_mci *host, unsigned int id)
* Card may have been plugged in prior to boot so we
* need to run the detect tasklet
*/
- queue_work(dw_mci_card_workqueue, &host->card_work);
+ queue_work(host->card_workqueue, &host->card_work);

return 0;
}
@@ -2021,9 +2019,9 @@ int dw_mci_probe(struct dw_mci *host)
mci_writel(host, CLKSRC, 0);

tasklet_init(&host->tasklet, dw_mci_tasklet_func, (unsigned long)host);
- dw_mci_card_workqueue = alloc_workqueue("dw-mci-card",
+ host->card_workqueue = alloc_workqueue("dw-mci-card",
WQ_MEM_RECLAIM | WQ_NON_REENTRANT, 1);
- if (!dw_mci_card_workqueue)
+ if (!host->card_workqueue)
goto err_dmaunmap;
INIT_WORK(&host->card_work, dw_mci_work_routine_card);
ret = request_irq(host->irq, dw_mci_interrupt, host->irq_flags, "dw-mci", host);
@@ -2085,7 +2083,7 @@ err_init_slot:
free_irq(host->irq, host);

err_workqueue:
- destroy_workqueue(dw_mci_card_workqueue);
+ destroy_workqueue(host->card_workqueue);

err_dmaunmap:
if (host->use_dma && host->dma_ops->exit)
@@ -2119,7 +2117,7 @@ void dw_mci_remove(struct dw_mci *host)
mci_writel(host, CLKSRC, 0);

free_irq(host->irq, host);
- destroy_workqueue(dw_mci_card_workqueue);
+ destroy_workqueue(host->card_workqueue);
dma_free_coherent(&host->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);

if (host->use_dma && host->dma_ops->exit)
diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
index 8f66e28..7a7ebd3 100644
--- a/include/linux/mmc/dw_mmc.h
+++ b/include/linux/mmc/dw_mmc.h
@@ -125,6 +125,7 @@ struct dw_mci {
struct mmc_request *mrq;
struct mmc_command *cmd;
struct mmc_data *data;
+ struct workqueue_struct *card_workqueue;

/* DMA interface members*/
int use_dma;
--
1.7.5.4


2012-05-02 03:08:09

by Jaehoon Chung

[permalink] [raw]
Subject: Re: [PATCH] mmc: dw_mmc: make multiple instances of dw_mci_card_workqueue

Acked-by: Jaehoon Chung <[email protected]>

On 05/02/2012 06:57 AM, Thomas Abraham wrote:

> The variable 'dw_mci_card_workqueue' is a global variable shared between
> multiple instances of the dw_mmc host controller. Due to this, data
> corruption has been noticed when multiple instances of dw_mmc controllers
> are actively reading/writing the media. Fix this by adding a instance
> of 'struct workqueue_struct' for each host instance and removing the
> global 'dw_mci_card_workqueue' instance.
>
> Signed-off-by: Thomas Abraham <[email protected]>
> ---
> drivers/mmc/host/dw_mmc.c | 14 ++++++--------
> include/linux/mmc/dw_mmc.h | 1 +
> 2 files changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> index ab3fc46..1532357 100644
> --- a/drivers/mmc/host/dw_mmc.c
> +++ b/drivers/mmc/host/dw_mmc.c
> @@ -100,8 +100,6 @@ struct dw_mci_slot {
> int last_detect_state;
> };
>
> -static struct workqueue_struct *dw_mci_card_workqueue;
> -
> #if defined(CONFIG_DEBUG_FS)
> static int dw_mci_req_show(struct seq_file *s, void *v)
> {
> @@ -1605,7 +1603,7 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
>
> if (pending & SDMMC_INT_CD) {
> mci_writel(host, RINTSTS, SDMMC_INT_CD);
> - queue_work(dw_mci_card_workqueue, &host->card_work);
> + queue_work(host->card_workqueue, &host->card_work);
> }
>
> /* Handle SDIO Interrupts */
> @@ -1844,7 +1842,7 @@ static int __init dw_mci_init_slot(struct dw_mci *host, unsigned int id)
> * Card may have been plugged in prior to boot so we
> * need to run the detect tasklet
> */
> - queue_work(dw_mci_card_workqueue, &host->card_work);
> + queue_work(host->card_workqueue, &host->card_work);
>
> return 0;
> }
> @@ -2021,9 +2019,9 @@ int dw_mci_probe(struct dw_mci *host)
> mci_writel(host, CLKSRC, 0);
>
> tasklet_init(&host->tasklet, dw_mci_tasklet_func, (unsigned long)host);
> - dw_mci_card_workqueue = alloc_workqueue("dw-mci-card",
> + host->card_workqueue = alloc_workqueue("dw-mci-card",
> WQ_MEM_RECLAIM | WQ_NON_REENTRANT, 1);
> - if (!dw_mci_card_workqueue)
> + if (!host->card_workqueue)
> goto err_dmaunmap;
> INIT_WORK(&host->card_work, dw_mci_work_routine_card);
> ret = request_irq(host->irq, dw_mci_interrupt, host->irq_flags, "dw-mci", host);
> @@ -2085,7 +2083,7 @@ err_init_slot:
> free_irq(host->irq, host);
>
> err_workqueue:
> - destroy_workqueue(dw_mci_card_workqueue);
> + destroy_workqueue(host->card_workqueue);
>
> err_dmaunmap:
> if (host->use_dma && host->dma_ops->exit)
> @@ -2119,7 +2117,7 @@ void dw_mci_remove(struct dw_mci *host)
> mci_writel(host, CLKSRC, 0);
>
> free_irq(host->irq, host);
> - destroy_workqueue(dw_mci_card_workqueue);
> + destroy_workqueue(host->card_workqueue);
> dma_free_coherent(&host->dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
>
> if (host->use_dma && host->dma_ops->exit)
> diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h
> index 8f66e28..7a7ebd3 100644
> --- a/include/linux/mmc/dw_mmc.h
> +++ b/include/linux/mmc/dw_mmc.h
> @@ -125,6 +125,7 @@ struct dw_mci {
> struct mmc_request *mrq;
> struct mmc_command *cmd;
> struct mmc_data *data;
> + struct workqueue_struct *card_workqueue;
>
> /* DMA interface members*/
> int use_dma;

2012-05-02 09:07:48

by Will Newton

[permalink] [raw]
Subject: Re: [PATCH] mmc: dw_mmc: make multiple instances of dw_mci_card_workqueue

On Tue, May 1, 2012 at 10:57 PM, Thomas Abraham
<[email protected]> wrote:
> The variable 'dw_mci_card_workqueue' is a global variable shared between
> multiple instances of the dw_mmc host controller. Due to this, data
> corruption has been noticed when multiple instances of dw_mmc controllers
> are actively reading/writing the media. Fix this by adding a instance
> of 'struct workqueue_struct' for each host instance and removing the
> global 'dw_mci_card_workqueue' instance.
>
> Signed-off-by: Thomas Abraham <[email protected]>
> ---
> ?drivers/mmc/host/dw_mmc.c ?| ? 14 ++++++--------
> ?include/linux/mmc/dw_mmc.h | ? ?1 +
> ?2 files changed, 7 insertions(+), 8 deletions(-)

Looks good.

Acked-by: Will Newton <[email protected]>