Re: [PATCH 3/4] PCI: Remove reset_fn field from pci_dev

2021-03-14 Thread Pali Rohár
On Friday 12 March 2021 23:04:51 ameynarkhed...@gmail.com wrote:
> From: Amey Narkhede 
> 
> reset_fn field is used to indicate whether the
> device supports any reset mechanism or not.
> Deprecate use of reset_fn in favor of new
> reset_methods bitmap which can be used to keep
> track of all supported reset mechanisms of a device.

Hello Amey!

You cannot trigger PCIe Hot Reset (PCI secondary bus reset) in this
simple way from sysfs via new reset methods.

I proposed very similar functionality just few days ago:
https://lore.kernel.org/linux-pci/20210301171221.3d42a55i7h5ubqsb@pali/T/#u

And I realized that it needs more steps to be done.

At least some remove-reset-rescan procedure done atomically is required.

> Signed-off-by: Amey Narkhede 
> ---
> Reviewed-by: Alex Williamson 
> Reviewed-by: Raphael Norwitz 
> 
>  drivers/net/ethernet/cavium/liquidio/lio_vf_main.c | 2 +-
>  drivers/pci/pci-sysfs.c| 6 ++
>  drivers/pci/pci.c  | 6 +++---
>  drivers/pci/probe.c| 1 -
>  drivers/pci/quirks.c   | 2 +-
>  include/linux/pci.h| 1 -
>  6 files changed, 7 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c 
> b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
> index 9b9d305c6..3e2c49e08 100644
> --- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
> +++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
> @@ -526,7 +526,7 @@ static void octeon_destroy_resources(struct octeon_device 
> *oct)
>   oct->irq_name_storage = NULL;
>   }
>   /* Soft reset the octeon device before exiting */
> - if (oct->pci_dev->reset_fn)
> + if (oct->pci_dev->reset_methods)
>   octeon_pci_flr(oct);
>   else
>   cn23xx_vf_ask_pf_to_do_flr(oct);
> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
> index f8afd54ca..78d2c130c 100644
> --- a/drivers/pci/pci-sysfs.c
> +++ b/drivers/pci/pci-sysfs.c
> @@ -1334,7 +1334,7 @@ static int pci_create_capabilities_sysfs(struct pci_dev 
> *dev)
> 
>   pcie_vpd_create_sysfs_dev_files(dev);
> 
> - if (dev->reset_fn) {
> + if (dev->reset_methods) {
>   retval = device_create_file(>dev, _attr_reset);
>   if (retval)
>   goto error;
> @@ -1417,10 +1417,8 @@ int __must_check pci_create_sysfs_dev_files(struct 
> pci_dev *pdev)
>  static void pci_remove_capabilities_sysfs(struct pci_dev *dev)
>  {
>   pcie_vpd_remove_sysfs_dev_files(dev);
> - if (dev->reset_fn) {
> + if (dev->reset_methods)
>   device_remove_file(>dev, _attr_reset);
> - dev->reset_fn = 0;
> - }
>  }
> 
>  /**
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 407b44e85..b7f6c6588 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5175,7 +5175,7 @@ int pci_reset_function(struct pci_dev *dev)
>  {
>   int rc;
> 
> - if (!dev->reset_fn)
> + if (!dev->reset_methods)
>   return -ENOTTY;
> 
>   pci_dev_lock(dev);
> @@ -5211,7 +5211,7 @@ int pci_reset_function_locked(struct pci_dev *dev)
>  {
>   int rc;
> 
> - if (!dev->reset_fn)
> + if (!dev->reset_methods)
>   return -ENOTTY;
> 
>   pci_dev_save_and_disable(dev);
> @@ -5234,7 +5234,7 @@ int pci_try_reset_function(struct pci_dev *dev)
>  {
>   int rc;
> 
> - if (!dev->reset_fn)
> + if (!dev->reset_methods)
>   return -ENOTTY;
> 
>   if (!pci_dev_trylock(dev))
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index 01dd037bd..4764e031a 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -2404,7 +2404,6 @@ static void pci_init_capabilities(struct pci_dev *dev)
> 
>   pcie_report_downtraining(dev);
>   pci_init_reset_methods(dev);
> - dev->reset_fn = !!dev->reset_methods;
>  }
> 
>  /*
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 0a3df84c9..20a81b1bc 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -5535,7 +5535,7 @@ static void 
> quirk_reset_lenovo_thinkpad_p50_nvgpu(struct pci_dev *pdev)
> 
>   if (pdev->subsystem_vendor != PCI_VENDOR_ID_LENOVO ||
>   pdev->subsystem_device != 0x222e ||
> - !pdev->reset_fn)
> + !pdev->reset_methods)
>   return;
> 
>   if (pci_enable_device_mem(pdev))
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 56d6e4750..a2f003f4e 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -437,7 +437,6 @@ struct pci_dev {
>   unsigned intstate_saved:1;
>   unsigned intis_physfn:1;
>   unsigned intis_virtfn:1;
> - unsigned intreset_fn:1;
>   unsigned intis_hotplug_bridge:1;
>   unsigned intshpc_managed:1; /* SHPC owned by shpchp */
>  

[PATCH 3/4] PCI: Remove reset_fn field from pci_dev

2021-03-12 Thread ameynarkhede03
From: Amey Narkhede 

reset_fn field is used to indicate whether the
device supports any reset mechanism or not.
Deprecate use of reset_fn in favor of new
reset_methods bitmap which can be used to keep
track of all supported reset mechanisms of a device.

Signed-off-by: Amey Narkhede 
---
Reviewed-by: Alex Williamson 
Reviewed-by: Raphael Norwitz 

 drivers/net/ethernet/cavium/liquidio/lio_vf_main.c | 2 +-
 drivers/pci/pci-sysfs.c| 6 ++
 drivers/pci/pci.c  | 6 +++---
 drivers/pci/probe.c| 1 -
 drivers/pci/quirks.c   | 2 +-
 include/linux/pci.h| 1 -
 6 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c 
b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
index 9b9d305c6..3e2c49e08 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
@@ -526,7 +526,7 @@ static void octeon_destroy_resources(struct octeon_device 
*oct)
oct->irq_name_storage = NULL;
}
/* Soft reset the octeon device before exiting */
-   if (oct->pci_dev->reset_fn)
+   if (oct->pci_dev->reset_methods)
octeon_pci_flr(oct);
else
cn23xx_vf_ask_pf_to_do_flr(oct);
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index f8afd54ca..78d2c130c 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -1334,7 +1334,7 @@ static int pci_create_capabilities_sysfs(struct pci_dev 
*dev)

pcie_vpd_create_sysfs_dev_files(dev);

-   if (dev->reset_fn) {
+   if (dev->reset_methods) {
retval = device_create_file(>dev, _attr_reset);
if (retval)
goto error;
@@ -1417,10 +1417,8 @@ int __must_check pci_create_sysfs_dev_files(struct 
pci_dev *pdev)
 static void pci_remove_capabilities_sysfs(struct pci_dev *dev)
 {
pcie_vpd_remove_sysfs_dev_files(dev);
-   if (dev->reset_fn) {
+   if (dev->reset_methods)
device_remove_file(>dev, _attr_reset);
-   dev->reset_fn = 0;
-   }
 }

 /**
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 407b44e85..b7f6c6588 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5175,7 +5175,7 @@ int pci_reset_function(struct pci_dev *dev)
 {
int rc;

-   if (!dev->reset_fn)
+   if (!dev->reset_methods)
return -ENOTTY;

pci_dev_lock(dev);
@@ -5211,7 +5211,7 @@ int pci_reset_function_locked(struct pci_dev *dev)
 {
int rc;

-   if (!dev->reset_fn)
+   if (!dev->reset_methods)
return -ENOTTY;

pci_dev_save_and_disable(dev);
@@ -5234,7 +5234,7 @@ int pci_try_reset_function(struct pci_dev *dev)
 {
int rc;

-   if (!dev->reset_fn)
+   if (!dev->reset_methods)
return -ENOTTY;

if (!pci_dev_trylock(dev))
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 01dd037bd..4764e031a 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2404,7 +2404,6 @@ static void pci_init_capabilities(struct pci_dev *dev)

pcie_report_downtraining(dev);
pci_init_reset_methods(dev);
-   dev->reset_fn = !!dev->reset_methods;
 }

 /*
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 0a3df84c9..20a81b1bc 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -5535,7 +5535,7 @@ static void quirk_reset_lenovo_thinkpad_p50_nvgpu(struct 
pci_dev *pdev)

if (pdev->subsystem_vendor != PCI_VENDOR_ID_LENOVO ||
pdev->subsystem_device != 0x222e ||
-   !pdev->reset_fn)
+   !pdev->reset_methods)
return;

if (pci_enable_device_mem(pdev))
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 56d6e4750..a2f003f4e 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -437,7 +437,6 @@ struct pci_dev {
unsigned intstate_saved:1;
unsigned intis_physfn:1;
unsigned intis_virtfn:1;
-   unsigned intreset_fn:1;
unsigned intis_hotplug_bridge:1;
unsigned intshpc_managed:1; /* SHPC owned by shpchp */
unsigned intis_thunderbolt:1;   /* Thunderbolt controller */
--
2.30.2