Re: [PATCH v7 1/4] PCI: Introduce pcim_alloc_irq_vectors()
From: Dejin Zheng <hidden>
Date: 2021-06-08 14:21:16
Also in:
linux-i2c, linux-pci, lkml
On Mon, Jun 07, 2021 at 07:12:34PM +0300, Andy Shevchenko wrote:
On Mon, Jun 07, 2021 at 11:39:13PM +0800, Dejin Zheng wrote:quoted
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....quoted
When CONFIG_PCI=n, there is no stub for pci_is_managed(), but pcim_alloc_irq_vectors() will use it, so add one like other similar stubs. Otherwise there can be build errors, as here by kernel test robot reported: include/linux/pci.h: In function 'pcim_alloc_irq_vectors':quoted
quoted
include/linux/pci.h:1847:7: error: implicit declaration of function 'pci_is_managed' [-Werror=implicit-function-declaration]1847 | if (!pci_is_managed(dev)) | ^~~~~~~~~~~~~~This is rather changelog related material. No need to pollute commit message with this.
Okey.
...quoted
Reported-by: kernel test robot <redacted>It's new functionality. Why this tag is here? Use comments (similar location than changelog) to give a credit if you wish.
Got it, Thanks!
quoted
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Robert Richter <rric@kernel.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Dejin Zheng <redacted> --- v6 -> v7: - rebase to PCI next branch - add a stub for pci_is_managed() when disable PCI for fix build error in sparc architecture. v5 -> v6: - rebase to 5.13-rc4 v4 -> v5: - Remove the check of enable device in pcim_alloc_irq_vectors() and make it as a static line function. v3 -> v4: - No change 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 | 5 +---- include/linux/pci.h | 25 +++++++++++++++++++++++++ 2 files changed, 26 insertions(+), 4 deletions(-)diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 452351025a09..e3b3fc59bd35 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c@@ -1989,10 +1989,7 @@ 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))diff --git a/include/linux/pci.h b/include/linux/pci.h index c20211e59a57..5783262c4643 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h@@ -1730,6 +1730,7 @@ static inline struct pci_dev *pci_get_class(unsigned int class, static inline void pci_set_master(struct pci_dev *dev) { } static inline int pci_enable_device(struct pci_dev *dev) { return -EIO; } +static inline int pci_is_managed(struct pci_dev *pdev) { return 0; } static inline void pci_disable_device(struct pci_dev *dev) { } static inline int pcim_enable_device(struct pci_dev *pdev) { return -EIO; } static inline int pci_assign_resource(struct pci_dev *dev, int i)@@ -1825,6 +1826,30 @@ pci_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs, NULL); } +/** + * 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. + */ +static inline int +pcim_alloc_irq_vectors(struct pci_dev *dev, unsigned int min_vecs, + unsigned int max_vecs, unsigned int flags) +{ + if (!pci_is_managed(dev)) + return -EINVAL; + return pci_alloc_irq_vectors(dev, min_vecs, max_vecs, flags); +} + /* Include architecture-dependent settings and functions */ #include <asm/pci.h>-- 2.30.1-- With Best Regards, Andy Shevchenko