Commit 8f12a311 authored by Lukas Wunner's avatar Lukas Wunner Committed by Daniel Vetter
Browse files

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 c8e9cf7b ("vga_switcheroo: Add a helper function to
  get the client state"):
  vga_switcheroo_get_client_state()

- Introduced by 0d69704a ("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: default avatarLukas Wunner <lukas@wunner.de>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent 945ef5bb

drivers/gpu/vga/vga_switcheroo.c

+32 −18
Original line number Diff line number Diff line
@@ -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;

}

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