diff mbox series

[v3,1/4] PCI: Introduce pcim_alloc_irq_vectors()

Message ID 20210216160249.749799-2-zhengdejin5@gmail.com (mailing list archive)
State Superseded
Delegated to: Bjorn Helgaas
Headers show
Series Introduce pcim_alloc_irq_vectors() | expand

Commit Message

Dejin Zheng Feb. 16, 2021, 4:02 p.m. UTC
Introduce pcim_alloc_irq_vectors(), a device-managed version of
pci_alloc_irq_vectors(). Introducing this function can simplify
the error handling path in many drivers.

And use pci_free_irq_vectors() to replace some code in pcim_release(),
they are equivalent, and no functional change. It is more explicit
that pcim_alloc_irq_vectors() is a device-managed function.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
---
v2 -> v3:
	- Add some commit comments for replace some codes in
	  pcim_release() by pci_free_irq_vectors().
v1 -> v2:
	- Use pci_free_irq_vectors() to replace some code in
	  pcim_release().
	- Modify some commit messages.

 drivers/pci/pci.c   | 33 +++++++++++++++++++++++++++++----
 include/linux/pci.h |  3 +++
 2 files changed, 32 insertions(+), 4 deletions(-)

Comments

Krzysztof Wilczyński Feb. 16, 2021, 5:53 p.m. UTC | #1
Hi Dejin,

> Introduce pcim_alloc_irq_vectors(), a device-managed version of
> pci_alloc_irq_vectors(). Introducing this function can simplify
> the error handling path in many drivers.
> 
> And use pci_free_irq_vectors() to replace some code in pcim_release(),
> they are equivalent, and no functional change. It is more explicit
> that pcim_alloc_irq_vectors() is a device-managed function.
[...]

Some suggestions about the commit message as per:

  https://lore.kernel.org/linux-pci/YCwE2cf9X%2FGd6lWy@rocinante/

> +/**
> + * pcim_alloc_irq_vectors - a device-managed pci_alloc_irq_vectors()
> + * @dev:		PCI device to operate on
> + * @min_vecs:		minimum number of vectors required (must be >= 1)
> + * @max_vecs:		maximum (desired) number of vectors
> + * @flags:		flags or quirks for the allocation
> + *
> + * Return the number of vectors allocated, (which might be smaller than
> + * @max_vecs) if successful, or a negative error code on error. If less
> + * than @min_vecs interrupt vectors are available for @dev the function
> + * will fail with -ENOSPC.
> + *
> + * It depends on calling pcim_enable_device() to make IRQ resources
> + * manageable.
> + */
> +int pcim_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
> +				unsigned int max_vecs, unsigned int flags)
> +{
> +	struct pci_devres *dr;
> +
> +	dr = find_pci_dr(dev);
> +	if (!dr || !dr->enabled)
> +		return -EINVAL;
> +
> +	return pci_alloc_irq_vectors(dev, min_vecs, max_vecs, flags);
> +}
> +EXPORT_SYMBOL(pcim_alloc_irq_vectors);
[...]

Looks good!  Thank you for adding kernel-doc here!  Much appreciated.

Reviewed-by: Krzysztof Wilczyński <kw@linux.com>

Krzysztof
diff mbox series

Patch

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index b67c4327d307..db799d089c85 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1969,10 +1969,7 @@  static void pcim_release(struct device *gendev, void *res)
 	struct pci_devres *this = res;
 	int i;
 
-	if (dev->msi_enabled)
-		pci_disable_msi(dev);
-	if (dev->msix_enabled)
-		pci_disable_msix(dev);
+	pci_free_irq_vectors(dev);
 
 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
 		if (this->region_mask & (1 << i))
@@ -2054,6 +2051,34 @@  void pcim_pin_device(struct pci_dev *pdev)
 }
 EXPORT_SYMBOL(pcim_pin_device);
 
+/**
+ * pcim_alloc_irq_vectors - a device-managed pci_alloc_irq_vectors()
+ * @dev:		PCI device to operate on
+ * @min_vecs:		minimum number of vectors required (must be >= 1)
+ * @max_vecs:		maximum (desired) number of vectors
+ * @flags:		flags or quirks for the allocation
+ *
+ * Return the number of vectors allocated, (which might be smaller than
+ * @max_vecs) if successful, or a negative error code on error. If less
+ * than @min_vecs interrupt vectors are available for @dev the function
+ * will fail with -ENOSPC.
+ *
+ * It depends on calling pcim_enable_device() to make IRQ resources
+ * manageable.
+ */
+int pcim_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+				unsigned int max_vecs, unsigned int flags)
+{
+	struct pci_devres *dr;
+
+	dr = find_pci_dr(dev);
+	if (!dr || !dr->enabled)
+		return -EINVAL;
+
+	return pci_alloc_irq_vectors(dev, min_vecs, max_vecs, flags);
+}
+EXPORT_SYMBOL(pcim_alloc_irq_vectors);
+
 /*
  * pcibios_add_device - provide arch specific hooks when adding device dev
  * @dev: the PCI device being added
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 86c799c97b77..d75ba85ddfc5 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1818,6 +1818,9 @@  pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
 					      NULL);
 }
 
+int pcim_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs,
+				unsigned int max_vecs, unsigned int flags);
+
 /* Include architecture-dependent settings and functions */
 
 #include <asm/pci.h>