Hide all the MSI-X vs MSI vs legacy bullshit, and provide an array of interrupt vectors in the pci_dev structure, and ensure we get proper interrupt affinity by default.
Signed-off-by: Christoph Hellwig <h...@lst.de> --- drivers/pci/irq.c | 89 ++++++++++++++++++++++++++++++++++++++++++++++++++++- drivers/pci/msi.c | 2 +- drivers/pci/pci.h | 5 +++ include/linux/pci.h | 5 +++ 4 files changed, 99 insertions(+), 2 deletions(-) diff --git a/drivers/pci/irq.c b/drivers/pci/irq.c index 6684f15..b683465 100644 --- a/drivers/pci/irq.c +++ b/drivers/pci/irq.c @@ -1,7 +1,8 @@ /* - * PCI IRQ failure handing code + * PCI IRQ handing code * * Copyright (c) 2008 James Bottomley <james.bottom...@hansenpartnership.com> + * Copyright (c) 2016 Christoph Hellwig. */ #include <linux/acpi.h> @@ -9,6 +10,92 @@ #include <linux/kernel.h> #include <linux/export.h> #include <linux/pci.h> +#include <linux/interrupt.h> +#include "pci.h" + +static int pci_nr_irq_vectors(struct pci_dev *pdev) +{ + int nr_entries; + + nr_entries = pci_msix_vec_count(pdev); + if (nr_entries <= 0 && pci_msi_supported(pdev, 1)) + nr_entries = pci_msi_vec_count(pdev); + if (nr_entries <= 0) + nr_entries = 1; + return nr_entries; +} + +static int pci_enable_msix_range_wrapper(struct pci_dev *pdev, u32 *irqs, + int nr_vecs) +{ + struct msix_entry *msix_entries; + int vecs, i; + + msix_entries = kcalloc(nr_vecs, sizeof(struct msix_entry), GFP_KERNEL); + if (!msix_entries) + return -ENOMEM; + + for (i = 0; i < nr_vecs; i++) + msix_entries[i].entry = i; + + vecs = pci_enable_msix_range(pdev, msix_entries, 1, nr_vecs); + if (vecs > 0) { + for (i = 0; i < vecs; i++) + irqs[i] = msix_entries[i].vector; + } + + kfree(msix_entries); + return vecs; +} + +int pci_alloc_irq_vectors(struct pci_dev *pdev, int nr_vecs) +{ + int vecs, ret, i; + u32 *irqs; + + nr_vecs = min(nr_vecs, pci_nr_irq_vectors(pdev)); + + irqs = kcalloc(nr_vecs, sizeof(u32), GFP_KERNEL); + if (!irqs) + return -ENOMEM; + + vecs = pci_enable_msix_range_wrapper(pdev, irqs, nr_vecs); + if (vecs <= 0) { + vecs = pci_enable_msi_range(pdev, 1, min(nr_vecs, 32)); + if (vecs <= 0) { + ret = -EIO; + if (!pdev->irq) + goto out_free_irqs; + + /* use legacy irq */ + vecs = 1; + } + + for (i = 0; i < vecs; i++) + irqs[i] = pdev->irq + i; + } + + pdev->irqs = irqs; + return vecs; + +out_free_irqs: + kfree(irqs); + return ret; +} +EXPORT_SYMBOL(pci_alloc_irq_vectors); + +void pci_free_irq_vectors(struct pci_dev *pdev) +{ + if (pdev->msi_enabled) + pci_disable_msi(pdev); + else if (pdev->msix_enabled) + pci_disable_msix(pdev); + + kfree(pdev->dev.irq_affinity); + pdev->dev.irq_affinity = NULL; + kfree(pdev->irqs); +} +EXPORT_SYMBOL(pci_free_irq_vectors); static void pci_note_irq_problem(struct pci_dev *pdev, const char *reason) { diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index a080f44..544d306 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -815,7 +815,7 @@ out_free: * to determine if MSI/-X are supported for the device. If MSI/-X is * supported return 1, else return 0. **/ -static int pci_msi_supported(struct pci_dev *dev, int nvec) +int pci_msi_supported(struct pci_dev *dev, int nvec) { struct pci_bus *bus; diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index d0fb934..263422c 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -144,8 +144,13 @@ extern unsigned int pci_pm_d3_delay; #ifdef CONFIG_PCI_MSI void pci_no_msi(void); +int pci_msi_supported(struct pci_dev *dev, int nvec); #else static inline void pci_no_msi(void) { } +static int pci_msi_supported(struct pci_dev *dev, int nvec) +{ + return 0; +} #endif static inline void pci_msi_set_enable(struct pci_dev *dev, int enable) diff --git a/include/linux/pci.h b/include/linux/pci.h index 004b813..4fbc14f 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -322,6 +322,7 @@ struct pci_dev { * directly, use the values stored here. They might be different! */ unsigned int irq; + unsigned int *irqs; struct resource resource[DEVICE_COUNT_RESOURCE]; /* I/O and memory regions + expansion ROMs */ bool match_driver; /* Skip attaching driver */ @@ -1235,6 +1236,9 @@ resource_size_t pcibios_iov_resource_alignment(struct pci_dev *dev, int resno); int pci_set_vga_state(struct pci_dev *pdev, bool decode, unsigned int command_bits, u32 flags); +int pci_alloc_irq_vectors(struct pci_dev *dev, int nr_vecs); +void pci_free_irq_vectors(struct pci_dev *pdev); + /* kmem_cache style wrapper around pci_alloc_consistent() */ #include <linux/pci-dma.h> @@ -1282,6 +1286,7 @@ static inline int pci_enable_msix_exact(struct pci_dev *dev, return rc; return 0; } + #else static inline int pci_msi_vec_count(struct pci_dev *dev) { return -ENOSYS; } static inline void pci_msi_shutdown(struct pci_dev *dev) { } -- 2.1.4