From bf3255b3cfe2d06280340dbac3f44b65d3ee6da3 Mon Sep 17 00:00:00 2001 From: Jean-Philippe Brucker Date: Mon, 3 Jun 2019 15:57:49 +0100 Subject: iommu: Add recoverable fault reporting Some IOMMU hardware features, for example PCI PRI and Arm SMMU Stall, enable recoverable I/O page faults. Allow IOMMU drivers to report PRI Page Requests and Stall events through the new fault reporting API. The consumer of the fault can be either an I/O page fault handler in the host, or a guest OS. Once handled, the fault must be completed by sending a page response back to the IOMMU. Add an iommu_page_response() function to complete a page fault. There are two ways to extend the userspace API: * Add a field to iommu_page_response and a flag to iommu_page_response::flags describing the validity of this field. * Introduce a new iommu_page_response_X structure with a different version number. The kernel must then support both versions. Signed-off-by: Jacob Pan Signed-off-by: Jean-Philippe Brucker Signed-off-by: Joerg Roedel --- include/linux/iommu.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'include/linux') diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 3e783f5bf472..76c8cda61dfd 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -227,6 +227,7 @@ struct iommu_sva_ops { * @sva_bind: Bind process address space to device * @sva_unbind: Unbind process address space from device * @sva_get_pasid: Get PASID associated to a SVA handle + * @page_response: handle page request response * @pgsize_bitmap: bitmap of all possible supported page sizes */ struct iommu_ops { @@ -287,6 +288,10 @@ struct iommu_ops { void (*sva_unbind)(struct iommu_sva *handle); int (*sva_get_pasid)(struct iommu_sva *handle); + int (*page_response)(struct device *dev, + struct iommu_fault_event *evt, + struct iommu_page_response *msg); + unsigned long pgsize_bitmap; }; @@ -311,19 +316,25 @@ struct iommu_device { * unrecoverable faults such as DMA or IRQ remapping faults. * * @fault: fault descriptor + * @list: pending fault event list, used for tracking responses */ struct iommu_fault_event { struct iommu_fault fault; + struct list_head list; }; /** * struct iommu_fault_param - per-device IOMMU fault data * @handler: Callback function to handle IOMMU faults at device level * @data: handler private data + * @faults: holds the pending faults which needs response + * @lock: protect pending faults list */ struct iommu_fault_param { iommu_dev_fault_handler_t handler; void *data; + struct list_head faults; + struct mutex lock; }; /** @@ -437,6 +448,8 @@ extern int iommu_unregister_device_fault_handler(struct device *dev); extern int iommu_report_device_fault(struct device *dev, struct iommu_fault_event *evt); +extern int iommu_page_response(struct device *dev, + struct iommu_page_response *msg); extern int iommu_group_id(struct iommu_group *group); extern struct iommu_group *iommu_group_get_for_dev(struct device *dev); @@ -765,6 +778,12 @@ int iommu_report_device_fault(struct device *dev, struct iommu_fault_event *evt) return -ENODEV; } +static inline int iommu_page_response(struct device *dev, + struct iommu_page_response *msg) +{ + return -ENODEV; +} + static inline int iommu_group_id(struct iommu_group *group) { return -ENODEV; -- cgit v1.2.3-71-gd317