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From: Philipp Stanner <pstanner@redhat.com>
To: Jonathan Corbet <corbet@lwn.net>,
	Hans de Goede <hdegoede@redhat.com>,
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
	Maxime Ripard <mripard@kernel.org>,
	Thomas Zimmermann <tzimmermann@suse.de>,
	David Airlie <airlied@gmail.com>,
	Daniel Vetter <daniel@ffwll.ch>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Philipp Stanner <pstanner@redhat.com>,
	Sam Ravnborg <sam@ravnborg.org>,
	dakr@redhat.com
Cc: linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	dri-devel@lists.freedesktop.org,
	linux-pci@vger.kernel.org
Subject: [PATCH v2 05/10] PCI: move dev-enabled status bit to struct pci_dev
Date: Tue, 23 Jan 2024 10:43:02 +0100
Message-ID: <20240123094317.15958-6-pstanner@redhat.com>
In-Reply-To: <20240123094317.15958-1-pstanner@redhat.com>
References: <20240123094317.15958-1-pstanner@redhat.com>
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The bit describing whether the PCI device is currently enabled is stored
in struct pci_devres. Besides this struct being subject of a cleanup
process, struct pci_device is in general the right place to store this
information, since it is not devres-specific.

Move the 'enabled' boolean bit to struct pci_dev.

Signed-off-by: Philipp Stanner <pstanner@redhat.com>
---
 drivers/pci/devres.c | 11 ++++-------
 drivers/pci/pci.c    | 17 ++++++++++-------
 drivers/pci/pci.h    |  1 -
 include/linux/pci.h  |  1 +
 4 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
index 7bff17633bc4..696541c65c8f 100644
--- a/drivers/pci/devres.c
+++ b/drivers/pci/devres.c
@@ -403,7 +403,7 @@ static void pcim_release(struct device *gendev, void *res)
 	if (this->restore_intx)
 		pci_intx(dev, this->orig_intx);
 
-	if (this->enabled && !this->pinned)
+	if (!this->pinned)
 		pci_disable_device(dev);
 }
 
@@ -448,14 +448,11 @@ int pcim_enable_device(struct pci_dev *pdev)
 	dr = get_pci_dr(pdev);
 	if (unlikely(!dr))
 		return -ENOMEM;
-	if (dr->enabled)
-		return 0;
 
 	rc = pci_enable_device(pdev);
-	if (!rc) {
+	if (!rc)
 		pdev->is_managed = 1;
-		dr->enabled = 1;
-	}
+
 	return rc;
 }
 EXPORT_SYMBOL(pcim_enable_device);
@@ -473,7 +470,7 @@ void pcim_pin_device(struct pci_dev *pdev)
 	struct pci_devres *dr;
 
 	dr = find_pci_dr(pdev);
-	WARN_ON(!dr || !dr->enabled);
+	WARN_ON(!dr || !pdev->enabled);
 	if (dr)
 		dr->pinned = 1;
 }
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index eb3ec59e8822..ab8d66e05662 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1953,6 +1953,9 @@ static int do_pci_enable_device(struct pci_dev *dev, int bars)
 	u16 cmd;
 	u8 pin;
 
+	if (dev->enabled)
+		return 0;
+
 	err = pci_set_power_state(dev, PCI_D0);
 	if (err < 0 && err != -EIO)
 		return err;
@@ -1967,7 +1970,7 @@ static int do_pci_enable_device(struct pci_dev *dev, int bars)
 	pci_fixup_device(pci_fixup_enable, dev);
 
 	if (dev->msi_enabled || dev->msix_enabled)
-		return 0;
+		goto success_out;
 
 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
 	if (pin) {
@@ -1977,6 +1980,8 @@ static int do_pci_enable_device(struct pci_dev *dev, int bars)
 					      cmd & ~PCI_COMMAND_INTX_DISABLE);
 	}
 
+success_out:
+	dev->enabled = true;
 	return 0;
 }
 
@@ -2146,6 +2151,9 @@ static void do_pci_disable_device(struct pci_dev *dev)
 {
 	u16 pci_command;
 
+	if (!dev->enabled)
+		return;
+
 	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
 	if (pci_command & PCI_COMMAND_MASTER) {
 		pci_command &= ~PCI_COMMAND_MASTER;
@@ -2153,6 +2161,7 @@ static void do_pci_disable_device(struct pci_dev *dev)
 	}
 
 	pcibios_disable_device(dev);
+	dev->enabled = false;
 }
 
 /**
@@ -2180,12 +2189,6 @@ void pci_disable_enabled_device(struct pci_dev *dev)
  */
 void pci_disable_device(struct pci_dev *dev)
 {
-	struct pci_devres *dr;
-
-	dr = find_pci_dr(dev);
-	if (dr)
-		dr->enabled = 0;
-
 	dev_WARN_ONCE(&dev->dev, atomic_read(&dev->enable_cnt) <= 0,
 		      "disabling already-disabled device");
 
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 7c2181677760..dbb76a3fb0e4 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -809,7 +809,6 @@ static inline pci_power_t mid_pci_get_power_state(struct pci_dev *pdev)
  * when a device is enabled using managed PCI device enable interface.
  */
 struct pci_devres {
-	unsigned int enabled:1;
 	unsigned int pinned:1;
 	unsigned int orig_intx:1;
 	unsigned int restore_intx:1;
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 641ee30f7d2d..a356bdcc14cc 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -367,6 +367,7 @@ struct pci_dev {
 					   this is D0-D3, D0 being fully
 					   functional, and D3 being off. */
 	u8		pm_cap;		/* PM capability offset */
+	unsigned int	enabled:1;	/* Whether this dev is enabled */
 	unsigned int	imm_ready:1;	/* Supports Immediate Readiness */
 	unsigned int	pme_support:5;	/* Bitmask of states from which PME#
 					   can be generated */
-- 
2.43.0