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vga_switcheroo: Add missing locking 

The following functions iterate over the client list, invoke client
callbacks or invoke handler callbacks without locking anything at all:

- Introduced by c8e9cf7bb2 ("vga_switcheroo: Add a helper function to
  get the client state"):
  vga_switcheroo_get_client_state()

- Introduced by 0d69704ae3 ("gpu/vga_switcheroo: add driver control
  power feature. (v3)"):
  vga_switcheroo_set_dynamic_switch()
  vga_switcheroo_runtime_suspend()
  vga_switcheroo_runtime_resume()
  vga_switcheroo_runtime_resume_hdmi_audio()

Refactor vga_switcheroo_runtime_resume_hdmi_audio() a bit to be able to
release vgasr_mutex immediately after iterating over the client list.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Lukas Wunner 2015-08-23 23:23:02 +02:00 committed by Daniel Vetter
parent 945ef5bb14
commit 8f12a3118f
1 changed files with 32 additions and 18 deletions
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50
drivers/gpu/vga/vga_switcheroo.c
View File

@ -347,13 +347,18 @@ find_active_client(struct list_head *head)
int vga_switcheroo_get_client_state(struct pci_dev *pdev)
{
struct vga_switcheroo_client *client;
enum vga_switcheroo_state ret;
mutex_lock(&vgasr_mutex);
client = find_client_from_pci(&vgasr_priv.clients, pdev);
if (!client)
return VGA_SWITCHEROO_NOT_FOUND;
if (!vgasr_priv.active)
return VGA_SWITCHEROO_INIT;
return client->pwr_state;
ret = VGA_SWITCHEROO_NOT_FOUND;
else if (!vgasr_priv.active)
ret = VGA_SWITCHEROO_INIT;
else
ret = client->pwr_state;
mutex_unlock(&vgasr_mutex);
return ret;
}
EXPORT_SYMBOL(vga_switcheroo_get_client_state);
@ -845,15 +850,16 @@ void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev,
{
struct vga_switcheroo_client *client;
mutex_lock(&vgasr_mutex);
client = find_client_from_pci(&vgasr_priv.clients, pdev);
if (!client)
return;
if (!client->driver_power_control)
if (!client || !client->driver_power_control) {
mutex_unlock(&vgasr_mutex);
return;
}
client->pwr_state = dynamic;
set_audio_state(client->id, dynamic);
mutex_unlock(&vgasr_mutex);
}
EXPORT_SYMBOL(vga_switcheroo_set_dynamic_switch);
@ -866,9 +872,11 @@ static int vga_switcheroo_runtime_suspend(struct device *dev)
ret = dev->bus->pm->runtime_suspend(dev);
if (ret)
return ret;
mutex_lock(&vgasr_mutex);
if (vgasr_priv.handler->switchto)
vgasr_priv.handler->switchto(VGA_SWITCHEROO_IGD);
vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_OFF);
mutex_unlock(&vgasr_mutex);
return 0;
}
@ -877,7 +885,9 @@ static int vga_switcheroo_runtime_resume(struct device *dev)
struct pci_dev *pdev = to_pci_dev(dev);
int ret;
mutex_lock(&vgasr_mutex);
vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_ON);
mutex_unlock(&vgasr_mutex);
ret = dev->bus->pm->runtime_resume(dev);
if (ret)
return ret;
@ -923,29 +933,33 @@ EXPORT_SYMBOL(vga_switcheroo_fini_domain_pm_ops);
static int vga_switcheroo_runtime_resume_hdmi_audio(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct vga_switcheroo_client *client;
struct device *video_dev = NULL;
int ret;
struct vga_switcheroo_client *client, *found = NULL;
/* we need to check if we have to switch back on the video
device so the audio device can come back */
mutex_lock(&vgasr_mutex);
list_for_each_entry(client, &vgasr_priv.clients, list) {
if (PCI_SLOT(client->pdev->devfn) == PCI_SLOT(pdev->devfn) &&
client_is_vga(client)) {
found = client;
ret = pm_runtime_get_sync(&client->pdev->dev);
if (ret) {
if (ret != 1)
return ret;
}
video_dev = &client->pdev->dev;
break;
}
}
mutex_unlock(&vgasr_mutex);
if (video_dev) {
ret = pm_runtime_get_sync(video_dev);
if (ret && ret != 1)
return ret;
}
ret = dev->bus->pm->runtime_resume(dev);
/* put the reference for the gpu */
if (found) {
pm_runtime_mark_last_busy(&found->pdev->dev);
pm_runtime_put_autosuspend(&found->pdev->dev);
if (video_dev) {
pm_runtime_mark_last_busy(video_dev);
pm_runtime_put_autosuspend(video_dev);
}
return ret;
}