Re: [PATCH v6 2/8] PCI/VGA: Deal only with VGA class devices

[Sui Jingfeng]

Hi,

On 2023/6/20 02:12, Limonciello, Mario wrote:


On 6/12/2023 2:25 PM, Sui Jingfeng wrote:

From: Sui Jingfeng 

Deal only with the VGA devcie(pdev->class == 0x0300), so replace the
pci_get_subsys() function with pci_get_class(). Filter the non-PCI 
display
device(pdev->class != 0x0300) out. There no need to process the 
non-display

PCI device.

Signed-off-by: Sui Jingfeng 
---

This also means that deleting a PCI device no longer needs
to walk the list.

Reviewed-by: Mario Limonciello 


Thanks a lot,

can you help to resend this precious R-B to the V7 of this series [1],

This is V6.

[1] https://patchwork.freedesktop.org/series/119250/


  drivers/pci/vgaarb.c | 22 --
  1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c
index c1bc6c983932..22a505e877dc 100644
--- a/drivers/pci/vgaarb.c
+++ b/drivers/pci/vgaarb.c
@@ -754,10 +754,6 @@ static bool vga_arbiter_add_pci_device(struct 
pci_dev *pdev)

  struct pci_dev *bridge;
  u16 cmd;
  -    /* Only deal with VGA class devices */
-    if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
-    return false;
-
  /* Allocate structure */
  vgadev = kzalloc(sizeof(struct vga_device), GFP_KERNEL);
  if (vgadev == NULL) {
@@ -1500,7 +1496,9 @@ static int pci_notify(struct notifier_block 
*nb, unsigned long action,

  struct pci_dev *pdev = to_pci_dev(dev);
  bool notify = false;
  -    vgaarb_dbg(dev, "%s\n", __func__);
+    /* Only deal with VGA class devices */
+    if (pdev->class != PCI_CLASS_DISPLAY_VGA << 8)
+    return 0;
    /* For now we're only intereted in devices added and removed. 
I didn't

   * test this thing here, so someone needs to double check for the
@@ -1510,6 +1508,8 @@ static int pci_notify(struct notifier_block 
*nb, unsigned long action,

  else if (action == BUS_NOTIFY_DEL_DEVICE)
  notify = vga_arbiter_del_pci_device(pdev);
  +    vgaarb_dbg(dev, "%s: action = %lu\n", __func__, action);
+
  if (notify)
  vga_arbiter_notify_clients();
  return 0;
@@ -1534,8 +1534,8 @@ static struct miscdevice vga_arb_device = {
    static int __init vga_arb_device_init(void)
  {
+    struct pci_dev *pdev = NULL;
  int rc;
-    struct pci_dev *pdev;
    rc = misc_register(_arb_device);
  if (rc < 0)
@@ -1545,11 +1545,13 @@ static int __init vga_arb_device_init(void)
    /* We add all PCI devices satisfying VGA class in the arbiter by
   * default */
-    pdev = NULL;
-    while ((pdev =
-    pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
-   PCI_ANY_ID, pdev)) != NULL)
+    while (1) {
+    pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev);
+    if (!pdev)
+    break;
+
  vga_arbiter_add_pci_device(pdev);
+    }
    pr_info("loaded\n");
  return rc;


--
Jingfeng

Re: [PATCH v6 2/8] PCI/VGA: Deal only with VGA class devices

[Limonciello, Mario]

On 6/12/2023 2:25 PM, Sui Jingfeng wrote:

From: Sui Jingfeng 

Deal only with the VGA devcie(pdev->class == 0x0300), so replace the
pci_get_subsys() function with pci_get_class(). Filter the non-PCI display
device(pdev->class != 0x0300) out. There no need to process the non-display
PCI device.

Signed-off-by: Sui Jingfeng 
---

This also means that deleting a PCI device no longer needs
to walk the list.

Reviewed-by: Mario Limonciello 


  drivers/pci/vgaarb.c | 22 --
  1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c
index c1bc6c983932..22a505e877dc 100644
--- a/drivers/pci/vgaarb.c
+++ b/drivers/pci/vgaarb.c
@@ -754,10 +754,6 @@ static bool vga_arbiter_add_pci_device(struct pci_dev 
*pdev)
struct pci_dev *bridge;
u16 cmd;
  
-	/* Only deal with VGA class devices */

-   if ((pdev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
-   return false;
-
/* Allocate structure */
vgadev = kzalloc(sizeof(struct vga_device), GFP_KERNEL);
if (vgadev == NULL) {
@@ -1500,7 +1496,9 @@ static int pci_notify(struct notifier_block *nb, unsigned 
long action,
struct pci_dev *pdev = to_pci_dev(dev);
bool notify = false;
  
-	vgaarb_dbg(dev, "%s\n", __func__);

+   /* Only deal with VGA class devices */
+   if (pdev->class != PCI_CLASS_DISPLAY_VGA << 8)
+   return 0;
  
  	/* For now we're only intereted in devices added and removed. I didn't

 * test this thing here, so someone needs to double check for the
@@ -1510,6 +1508,8 @@ static int pci_notify(struct notifier_block *nb, unsigned 
long action,
else if (action == BUS_NOTIFY_DEL_DEVICE)
notify = vga_arbiter_del_pci_device(pdev);
  
+	vgaarb_dbg(dev, "%s: action = %lu\n", __func__, action);

+
if (notify)
vga_arbiter_notify_clients();
return 0;
@@ -1534,8 +1534,8 @@ static struct miscdevice vga_arb_device = {
  
  static int __init vga_arb_device_init(void)

  {
+   struct pci_dev *pdev = NULL;
int rc;
-   struct pci_dev *pdev;
  
  	rc = misc_register(_arb_device);

if (rc < 0)
@@ -1545,11 +1545,13 @@ static int __init vga_arb_device_init(void)
  
  	/* We add all PCI devices satisfying VGA class in the arbiter by

 * default */
-   pdev = NULL;
-   while ((pdev =
-   pci_get_subsys(PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
-  PCI_ANY_ID, pdev)) != NULL)
+   while (1) {
+   pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev);
+   if (!pdev)
+   break;
+
vga_arbiter_add_pci_device(pdev);
+   }
  
  	pr_info("loaded\n");

return rc;