When working on another SATA driver that uses libahci_platform, I
noticed an error in this driver; it tries to the the driver data for its
device, while libata also thinks it can set the driver data. See:
ahci_platform_init_host()
-> ata_host_alloc_pinfo()
-> ata_host_alloc()
-> dev_set_drvdata()
So instead of sticking the IP-specific platform data into drvdata, let's
use the plat_data variable that is reserved for this use.
Signed-off-by: Brian Norris <[email protected]>
Cc: Srinivas Kandagatla <[email protected]>
Cc: Maxime Coquelin <[email protected]>
Cc: Patrice Chotard <[email protected]>
---
This is ONLY compile tested; I don't have hardware to run. This looks like it
could have ramifications on suspend/resume support, and hot device removal
(e.g., sysfs unbind), so it might qualify as -stable, if someone can test it
drivers/ata/ahci_st.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)
diff --git a/drivers/ata/ahci_st.c b/drivers/ata/ahci_st.c
index bc971af262e7..2bd2375c2ab1 100644
--- a/drivers/ata/ahci_st.c
+++ b/drivers/ata/ahci_st.c
@@ -37,7 +37,6 @@ struct st_ahci_drv_data {
struct reset_control *pwr;
struct reset_control *sw_rst;
struct reset_control *pwr_rst;
- struct ahci_host_priv *hpriv;
};
static void st_ahci_configure_oob(void __iomem *mmio)
@@ -57,7 +56,9 @@ static void st_ahci_configure_oob(void __iomem *mmio)
static int st_ahci_deassert_resets(struct device *dev)
{
- struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
+ struct ata_host *host = dev_get_drvdata(dev);
+ struct ahci_host_priv *hpriv = host->private_data;
+ struct st_ahci_drv_data *drv_data = hpriv->plat_data;
int err;
if (drv_data->pwr) {
@@ -68,7 +69,7 @@ static int st_ahci_deassert_resets(struct device *dev)
}
}
- st_ahci_configure_oob(drv_data->hpriv->mmio);
+ st_ahci_configure_oob(hpriv->mmio);
if (drv_data->sw_rst) {
err = reset_control_deassert(drv_data->sw_rst);
@@ -92,8 +93,8 @@ static int st_ahci_deassert_resets(struct device *dev)
static void st_ahci_host_stop(struct ata_host *host)
{
struct ahci_host_priv *hpriv = host->private_data;
+ struct st_ahci_drv_data *drv_data = hpriv->plat_data;
struct device *dev = host->dev;
- struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
int err;
if (drv_data->pwr) {
@@ -107,7 +108,9 @@ static void st_ahci_host_stop(struct ata_host *host)
static int st_ahci_probe_resets(struct platform_device *pdev)
{
- struct st_ahci_drv_data *drv_data = platform_get_drvdata(pdev);
+ struct ata_host *host = dev_get_drvdata(&pdev->dev);
+ struct ahci_host_priv *hpriv = host->private_data;
+ struct st_ahci_drv_data *drv_data = hpriv->plat_data;
drv_data->pwr = devm_reset_control_get(&pdev->dev, "pwr-dwn");
if (IS_ERR(drv_data->pwr)) {
@@ -161,8 +164,7 @@ static int st_ahci_probe(struct platform_device *pdev)
hpriv = ahci_platform_get_resources(pdev);
if (IS_ERR(hpriv))
return PTR_ERR(hpriv);
-
- drv_data->hpriv = hpriv;
+ hpriv->plat_data = drv_data;
err = st_ahci_probe_resets(pdev);
if (err)
@@ -185,8 +187,9 @@ static int st_ahci_probe(struct platform_device *pdev)
#ifdef CONFIG_PM_SLEEP
static int st_ahci_suspend(struct device *dev)
{
- struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
- struct ahci_host_priv *hpriv = drv_data->hpriv;
+ struct ata_host *host = dev_get_drvdata(dev);
+ struct ahci_host_priv *hpriv = host->private_data;
+ struct st_ahci_drv_data *drv_data = hpriv->plat_data;
int err;
err = ahci_platform_suspend_host(dev);
@@ -208,8 +211,8 @@ static int st_ahci_suspend(struct device *dev)
static int st_ahci_resume(struct device *dev)
{
- struct st_ahci_drv_data *drv_data = dev_get_drvdata(dev);
- struct ahci_host_priv *hpriv = drv_data->hpriv;
+ struct ata_host *host = dev_get_drvdata(dev);
+ struct ahci_host_priv *hpriv = host->private_data;
int err;
err = ahci_platform_enable_resources(hpriv);
--
1.9.1
Hello Brian,
On 04/08/2015 08:59 PM, Brian Norris wrote:
> When working on another SATA driver that uses libahci_platform, I
> noticed an error in this driver; it tries to the the driver data for its
> device, while libata also thinks it can set the driver data. See:
>
> ahci_platform_init_host()
> -> ata_host_alloc_pinfo()
> -> ata_host_alloc()
> -> dev_set_drvdata()
>
> So instead of sticking the IP-specific platform data into drvdata, let's
> use the plat_data variable that is reserved for this use.
>
> Signed-off-by: Brian Norris <[email protected]>
> Cc: Srinivas Kandagatla <[email protected]>
> Cc: Maxime Coquelin <[email protected]>
> Cc: Patrice Chotard <[email protected]>
> ---
> This is ONLY compile tested; I don't have hardware to run. This looks like it
> could have ramifications on suspend/resume support, and hot device removal
> (e.g., sysfs unbind), so it might qualify as -stable, if someone can test it
>
> drivers/ata/ahci_st.c | 25 ++++++++++++++-----------
> 1 file changed, 14 insertions(+), 11 deletions(-)
>
>
Your patch looks sensible, thanks for spotting this issue.
Peter, do you have the SATA setup in place to test Brian's patch?
Once tested, you can add my:
Acked-by: Maxime Coquelin <[email protected]>
Thanks,
Maxime
Hello.
On 4/8/2015 9:59 PM, Brian Norris wrote:
> When working on another SATA driver that uses libahci_platform, I
> noticed an error in this driver; it tries to the the driver data for its
> device, while libata also thinks it can set the driver data. See:
> ahci_platform_init_host()
> -> ata_host_alloc_pinfo()
> -> ata_host_alloc()
> -> dev_set_drvdata()
> So instead of sticking the IP-specific platform data into drvdata, let's
> use the plat_data variable that is reserved for this use.
> Signed-off-by: Brian Norris <[email protected]>
> Cc: Srinivas Kandagatla <[email protected]>
> Cc: Maxime Coquelin <[email protected]>
> Cc: Patrice Chotard <[email protected]>
> ---
> This is ONLY compile tested; I don't have hardware to run. This looks like it
> could have ramifications on suspend/resume support, and hot device removal
> (e.g., sysfs unbind), so it might qualify as -stable, if someone can test it
> drivers/ata/ahci_st.c | 25 ++++++++++++++-----------
> 1 file changed, 14 insertions(+), 11 deletions(-)
> diff --git a/drivers/ata/ahci_st.c b/drivers/ata/ahci_st.c
> index bc971af262e7..2bd2375c2ab1 100644
> --- a/drivers/ata/ahci_st.c
> +++ b/drivers/ata/ahci_st.c
[...]
> @@ -107,7 +108,9 @@ static void st_ahci_host_stop(struct ata_host *host)
>
> static int st_ahci_probe_resets(struct platform_device *pdev)
> {
> - struct st_ahci_drv_data *drv_data = platform_get_drvdata(pdev);
> + struct ata_host *host = dev_get_drvdata(&pdev->dev);
Why not just platform_get_drvdata()?
[...]
MBR, Sergei
Hi Maxime,
On Thu, 09 Apr 2015, Maxime Coquelin wrote:
> Hello Brian,
>
<snip>
> > drivers/ata/ahci_st.c | 25 ++++++++++++++-----------
> > 1 file changed, 14 insertions(+), 11 deletions(-)
> >
> >
>
> Your patch looks sensible, thanks for spotting this issue.
>
> Peter, do you have the SATA setup in place to test Brian's patch?
Yes I can test, although not until Saturday as I only have remote
access to the board today & tomorrow and the hard drive isn't
plugged in.
regards,
Peter.
On Thu, Apr 09, 2015 at 12:34:02PM +0300, Sergei Shtylyov wrote:
> Hello.
>
> On 4/8/2015 9:59 PM, Brian Norris wrote:
>
> >When working on another SATA driver that uses libahci_platform, I
> >noticed an error in this driver; it tries to the the driver data for its
> >device, while libata also thinks it can set the driver data. See:
>
> > ahci_platform_init_host()
> > -> ata_host_alloc_pinfo()
> > -> ata_host_alloc()
> > -> dev_set_drvdata()
>
> >So instead of sticking the IP-specific platform data into drvdata, let's
> >use the plat_data variable that is reserved for this use.
>
> >Signed-off-by: Brian Norris <[email protected]>
> >Cc: Srinivas Kandagatla <[email protected]>
> >Cc: Maxime Coquelin <[email protected]>
> >Cc: Patrice Chotard <[email protected]>
> >---
> >This is ONLY compile tested; I don't have hardware to run. This looks like it
> >could have ramifications on suspend/resume support, and hot device removal
> >(e.g., sysfs unbind), so it might qualify as -stable, if someone can test it
>
> > drivers/ata/ahci_st.c | 25 ++++++++++++++-----------
> > 1 file changed, 14 insertions(+), 11 deletions(-)
>
> >diff --git a/drivers/ata/ahci_st.c b/drivers/ata/ahci_st.c
> >index bc971af262e7..2bd2375c2ab1 100644
> >--- a/drivers/ata/ahci_st.c
> >+++ b/drivers/ata/ahci_st.c
> [...]
> >@@ -107,7 +108,9 @@ static void st_ahci_host_stop(struct ata_host *host)
> >
> > static int st_ahci_probe_resets(struct platform_device *pdev)
> > {
> >- struct st_ahci_drv_data *drv_data = platform_get_drvdata(pdev);
> >+ struct ata_host *host = dev_get_drvdata(&pdev->dev);
>
> Why not just platform_get_drvdata()?
Just being consistent, as that's what the rest of the driver uses. It
seems like it'd be easy to misconstrue dev_get_drvrdata(&pdev->dev) and
platform_get_drvdata(pdev) as two different things (e.g., when
grepping), when in fact they are the same. Seems like a needless source
of potential confusion.
Why should I use platform_get_drvdata()?
(NB: I didn't notice at first that the driver already was using
platform_get_drvdata(). I pretty much ignored anything that was already
there, since it was all wrong anyway.)
Anyway, I don't care either way, and in fact, I don't care about this
driver much at all as I never expect to use it; I just noticed the
defect when reading.
Brian
On Thu, Apr 09, 2015 at 10:43:10AM +0100, Peter Griffin wrote:
> Yes I can test, although not until Saturday as I only have remote
> access to the board today & tomorrow and the hard drive isn't
> plugged in.
What's the status on this patch? Should I push it through
for-4.1-fixes?
Thanks.
--
tejun
Hi Tejun,
On Fri, 17 Apr 2015, Tejun Heo wrote:
> On Thu, Apr 09, 2015 at 10:43:10AM +0100, Peter Griffin wrote:
> > Yes I can test, although not until Saturday as I only have remote
> > access to the board today & tomorrow and the hard drive isn't
> > plugged in.
>
> What's the status on this patch? Should I push it through
> for-4.1-fixes?
The layering violation which Brian identified does need fixing. However
please don't take this patch as it currently is, as it causes a NULL
ptr dereference.
I can send an updated version in a moment which: -
1) Fixes the conflict you will get when applying it for v4.1
(due to my "st_configure_oob must be called after IP is clocked" patch).
2) Fixes the crash which this patch introduces.
regards,
Peter.