From 69031f500865ee3eee19566a1b9c40a189817eaa Mon Sep 17 00:00:00 2001 From: Claire Chang Date: Sat, 19 Jun 2021 11:40:34 +0800 Subject: swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used Always have the pointer to the swiotlb pool used in struct device. This could help simplify the code for other pools. Signed-off-by: Claire Chang Reviewed-by: Christoph Hellwig Tested-by: Stefano Stabellini Tested-by: Will Deacon Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk --- include/linux/device.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux/device.h') diff --git a/include/linux/device.h b/include/linux/device.h index 59940f1744c1..2a22875238a6 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -423,6 +423,7 @@ struct dev_links_info { * @dma_pools: Dma pools (if dma'ble device). * @dma_mem: Internal for coherent mem override. * @cma_area: Contiguous memory area for dma allocations + * @dma_io_tlb_mem: Pointer to the swiotlb pool used. Not for driver use. * @archdata: For arch-specific additions. * @of_node: Associated device tree node. * @fwnode: Associated device node supplied by platform firmware. @@ -531,6 +532,9 @@ struct device { #ifdef CONFIG_DMA_CMA struct cma *cma_area; /* contiguous memory area for dma allocations */ +#endif +#ifdef CONFIG_SWIOTLB + struct io_tlb_mem *dma_io_tlb_mem; #endif /* arch specific additions */ struct dev_archdata archdata; -- cgit v1.2.3 From 77e89afc25f30abd56e76a809ee2884d7c1b63ce Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 29 Jul 2021 23:51:47 +0200 Subject: PCI/MSI: Protect msi_desc::masked for multi-MSI Multi-MSI uses a single MSI descriptor and there is a single mask register when the device supports per vector masking. To avoid reading back the mask register the value is cached in the MSI descriptor and updates are done by clearing and setting bits in the cache and writing it to the device. But nothing protects msi_desc::masked and the mask register from being modified concurrently on two different CPUs for two different Linux interrupts which belong to the same multi-MSI descriptor. Add a lock to struct device and protect any operation on the mask and the mask register with it. This makes the update of msi_desc::masked unconditional, but there is no place which requires a modification of the hardware register without updating the masked cache. msi_mask_irq() is now an empty wrapper which will be cleaned up in follow up changes. The problem goes way back to the initial support of multi-MSI, but picking the commit which introduced the mask cache is a valid cut off point (2.6.30). Fixes: f2440d9acbe8 ("PCI MSI: Refactor interrupt masking code") Signed-off-by: Thomas Gleixner Tested-by: Marc Zyngier Reviewed-by: Marc Zyngier Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.726833414@linutronix.de --- drivers/base/core.c | 1 + drivers/pci/msi.c | 19 ++++++++++--------- include/linux/device.h | 1 + include/linux/msi.h | 2 +- 4 files changed, 13 insertions(+), 10 deletions(-) (limited to 'include/linux/device.h') diff --git a/drivers/base/core.c b/drivers/base/core.c index f6360490a4a3..6c0ef9d55a34 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -2837,6 +2837,7 @@ void device_initialize(struct device *dev) device_pm_init(dev); set_dev_node(dev, -1); #ifdef CONFIG_GENERIC_MSI_IRQ + raw_spin_lock_init(&dev->msi_lock); INIT_LIST_HEAD(&dev->msi_list); #endif INIT_LIST_HEAD(&dev->links.consumers); diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index f0f7026b7ac0..e5e75331b415 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -143,24 +143,25 @@ static inline __attribute_const__ u32 msi_mask(unsigned x) * reliably as devices without an INTx disable bit will then generate a * level IRQ which will never be cleared. */ -u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) +void __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) { - u32 mask_bits = desc->masked; + raw_spinlock_t *lock = &desc->dev->msi_lock; + unsigned long flags; if (pci_msi_ignore_mask || !desc->msi_attrib.maskbit) - return 0; + return; - mask_bits &= ~mask; - mask_bits |= flag; + raw_spin_lock_irqsave(lock, flags); + desc->masked &= ~mask; + desc->masked |= flag; pci_write_config_dword(msi_desc_to_pci_dev(desc), desc->mask_pos, - mask_bits); - - return mask_bits; + desc->masked); + raw_spin_unlock_irqrestore(lock, flags); } static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) { - desc->masked = __pci_msi_desc_mask_irq(desc, mask, flag); + __pci_msi_desc_mask_irq(desc, mask, flag); } static void __iomem *pci_msix_desc_addr(struct msi_desc *desc) diff --git a/include/linux/device.h b/include/linux/device.h index 59940f1744c1..e53aa5065f58 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -506,6 +506,7 @@ struct device { struct dev_pin_info *pins; #endif #ifdef CONFIG_GENERIC_MSI_IRQ + raw_spinlock_t msi_lock; struct list_head msi_list; #endif #ifdef CONFIG_DMA_OPS diff --git a/include/linux/msi.h b/include/linux/msi.h index 6aff469e511d..e8bdcb83172b 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -233,7 +233,7 @@ void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg); void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg); u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag); -u32 __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag); +void __pci_msi_desc_mask_irq(struct msi_desc *desc, u32 mask, u32 flag); void pci_msi_mask_irq(struct irq_data *data); void pci_msi_unmask_irq(struct irq_data *data); -- cgit v1.2.3 From 7a3dc4f35bf8e1a07e5c3f8ecc8ac923f48493fe Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 13 Aug 2021 12:36:14 +0200 Subject: driver core: Add missing kernel doc for device::msi_lock Fixes: 77e89afc25f3 ("PCI/MSI: Protect msi_desc::masked for multi-MSI") Reported-by: Stephen Rothwell Signed-off-by: Thomas Gleixner --- include/linux/device.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/device.h') diff --git a/include/linux/device.h b/include/linux/device.h index e53aa5065f58..65d84b67b024 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -407,6 +407,7 @@ struct dev_links_info { * @em_pd: device's energy model performance domain * @pins: For device pin management. * See Documentation/driver-api/pin-control.rst for details. + * @msi_lock: Lock to protect MSI mask cache and mask register * @msi_list: Hosts MSI descriptors * @msi_domain: The generic MSI domain this device is using. * @numa_node: NUMA node this device is close to. -- cgit v1.2.3