From 99b3c58f7ba7fae801e501b45c5fcf6e08d9247f Mon Sep 17 00:00:00 2001 From: Piotr Gregor Date: Fri, 26 May 2017 22:02:25 +0100 Subject: PCI: Test INTx masking during enumeration, not at run-time The test for INTx masking via PCI_COMMAND_INTX_DISABLE performed in pci_intx_mask_supported() should be done before the device can be used. This is to avoid writing PCI_COMMAND while the driver owns the device, in case that has any effect on MSI/MSI-X interrupts. Move the content of pci_intx_mask_supported() to pci_intx_mask_broken() and call it from pci_setup_device(). The test result can be queried at any time later using the same pci_intx_mask_supported() interface as before (though with changed implementation), so callers (uio, vfio) should be unaffected. Signed-off-by: Piotr Gregor [bhelgaas: changelog, remove quirk check, remove locking, move dev->broken_intx_masking assignment to caller] Signed-off-by: Bjorn Helgaas Reviewed-by: Alex Williamson Acked-by: Michael S. Tsirkin --- include/linux/pci.h | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'include/linux/pci.h') diff --git a/include/linux/pci.h b/include/linux/pci.h index 33c2b0b77429..4f0613d5d2d9 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -366,7 +366,7 @@ struct pci_dev { unsigned int is_thunderbolt:1; /* Thunderbolt controller */ unsigned int __aer_firmware_first_valid:1; unsigned int __aer_firmware_first:1; - unsigned int broken_intx_masking:1; + unsigned int broken_intx_masking:1; /* INTx masking can't be used */ unsigned int io_window_1k:1; /* Intel P2P bridge 1K I/O windows */ unsigned int irq_managed:1; unsigned int has_secondary_link:1; @@ -1003,6 +1003,15 @@ int __must_check pci_reenable_device(struct pci_dev *); int __must_check pcim_enable_device(struct pci_dev *pdev); void pcim_pin_device(struct pci_dev *pdev); +static inline bool pci_intx_mask_supported(struct pci_dev *pdev) +{ + /* + * INTx masking is supported if PCI_COMMAND_INTX_DISABLE is + * writable and no quirk has marked the feature broken. + */ + return !pdev->broken_intx_masking; +} + static inline int pci_is_enabled(struct pci_dev *pdev) { return (atomic_read(&pdev->enable_cnt) > 0); @@ -1026,7 +1035,6 @@ int __must_check pci_set_mwi(struct pci_dev *dev); int pci_try_set_mwi(struct pci_dev *dev); void pci_clear_mwi(struct pci_dev *dev); void pci_intx(struct pci_dev *dev, int enable); -bool pci_intx_mask_supported(struct pci_dev *dev); bool pci_check_and_mask_intx(struct pci_dev *dev); bool pci_check_and_unmask_intx(struct pci_dev *dev); int pci_wait_for_pending(struct pci_dev *dev, int pos, u16 mask); -- cgit