From: Jacob Pan <jacob.jun....@linux.intel.com> Device faults detected by IOMMU can be reported outside the IOMMU subsystem for further processing. This patch introduces a generic device fault data structure.
The fault can be either an unrecoverable fault or a page request, also referred to as a recoverable fault. We only care about non internal faults that are likely to be reported to an external subsystem. Signed-off-by: Jacob Pan <jacob.jun....@linux.intel.com> Signed-off-by: Jean-Philippe Brucker <jean-philippe.bruc...@arm.com> Signed-off-by: Liu, Yi L <yi.l....@linux.intel.com> Signed-off-by: Ashok Raj <ashok....@intel.com> Signed-off-by: Eric Auger <eric.au...@redhat.com> --- v4 -> v5: - simplified struct iommu_fault_event comment - Moved IOMMU_FAULT_PERM outside of the struct - Removed IOMMU_FAULT_PERM_INST - s/IOMMU_FAULT_PAGE_REQUEST_PASID_PRESENT/ IOMMU_FAULT_PAGE_REQUEST_PASID_VALID v3 -> v4: - use a union containing aither an unrecoverable fault or a page request message. Move the device private data in the page request structure. Reshuffle the fields and use flags. - move fault perm attributes to the uapi - remove a bunch of iommu_fault_reason enum values that were related to internal errors --- include/linux/iommu.h | 44 ++++++++++++++ include/uapi/linux/iommu.h | 115 +++++++++++++++++++++++++++++++++++++ 2 files changed, 159 insertions(+) create mode 100644 include/uapi/linux/iommu.h diff --git a/include/linux/iommu.h b/include/linux/iommu.h index ffbbc7e39cee..c6f398f7e6e0 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -25,6 +25,7 @@ #include <linux/errno.h> #include <linux/err.h> #include <linux/of.h> +#include <uapi/linux/iommu.h> #define IOMMU_READ (1 << 0) #define IOMMU_WRITE (1 << 1) @@ -48,6 +49,7 @@ struct bus_type; struct device; struct iommu_domain; struct notifier_block; +struct iommu_fault_event; /* iommu fault flags */ #define IOMMU_FAULT_READ 0x0 @@ -55,6 +57,7 @@ struct notifier_block; typedef int (*iommu_fault_handler_t)(struct iommu_domain *, struct device *, unsigned long, int, void *); +typedef int (*iommu_dev_fault_handler_t)(struct iommu_fault_event *, void *); struct iommu_domain_geometry { dma_addr_t aperture_start; /* First address that can be mapped */ @@ -247,6 +250,46 @@ struct iommu_device { struct device *dev; }; +/** + * struct iommu_fault_event - Generic fault event + * + * Can represent recoverable faults such as a page requests or + * unrecoverable faults such as DMA or IRQ remapping faults. + * + * @fault: fault descriptor + * @iommu_private: used by the IOMMU driver for storing fault-specific + * data. Users should not modify this field before + * sending the fault response. + */ +struct iommu_fault_event { + struct iommu_fault fault; + u64 iommu_private; +}; + +/** + * struct iommu_fault_param - per-device IOMMU fault data + * @dev_fault_handler: Callback function to handle IOMMU faults at device level + * @data: handler private data + * + */ +struct iommu_fault_param { + iommu_dev_fault_handler_t handler; + void *data; +}; + +/** + * struct iommu_param - collection of per-device IOMMU data + * + * @fault_param: IOMMU detected device fault reporting data + * + * TODO: migrate other per device data pointers under iommu_dev_data, e.g. + * struct iommu_group *iommu_group; + * struct iommu_fwspec *iommu_fwspec; + */ +struct iommu_param { + struct iommu_fault_param *fault_param; +}; + int iommu_device_register(struct iommu_device *iommu); void iommu_device_unregister(struct iommu_device *iommu); int iommu_device_sysfs_add(struct iommu_device *iommu, @@ -422,6 +465,7 @@ struct iommu_ops {}; struct iommu_group {}; struct iommu_fwspec {}; struct iommu_device {}; +struct iommu_fault_param {}; static inline bool iommu_present(struct bus_type *bus) { diff --git a/include/uapi/linux/iommu.h b/include/uapi/linux/iommu.h new file mode 100644 index 000000000000..edcc0dda7993 --- /dev/null +++ b/include/uapi/linux/iommu.h @@ -0,0 +1,115 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * IOMMU user API definitions + */ + +#ifndef _UAPI_IOMMU_H +#define _UAPI_IOMMU_H + +#include <linux/types.h> + +#define IOMMU_FAULT_PERM_WRITE (1 << 0) /* write */ +#define IOMMU_FAULT_PERM_EXEC (1 << 1) /* exec */ +#define IOMMU_FAULT_PERM_PRIV (1 << 2) /* privileged */ + +/* Generic fault types, can be expanded IRQ remapping fault */ +enum iommu_fault_type { + IOMMU_FAULT_DMA_UNRECOV = 1, /* unrecoverable fault */ + IOMMU_FAULT_PAGE_REQ, /* page request fault */ +}; + +enum iommu_fault_reason { + IOMMU_FAULT_REASON_UNKNOWN = 0, + + /* Could not access the PASID table (fetch caused external abort) */ + IOMMU_FAULT_REASON_PASID_FETCH, + + /* pasid entry is invalid or has configuration errors */ + IOMMU_FAULT_REASON_BAD_PASID_ENTRY, + + /* + * PASID is out of range (e.g. exceeds the maximum PASID + * supported by the IOMMU) or disabled. + */ + IOMMU_FAULT_REASON_PASID_INVALID, + + /* + * An external abort occurred fetching (or updating) a translation + * table descriptor + */ + IOMMU_FAULT_REASON_WALK_EABT, + + /* + * Could not access the page table entry (Bad address), + * actual translation fault + */ + IOMMU_FAULT_REASON_PTE_FETCH, + + /* Protection flag check failed */ + IOMMU_FAULT_REASON_PERMISSION, + + /* access flag check failed */ + IOMMU_FAULT_REASON_ACCESS, + + /* Output address of a translation stage caused Address Size fault */ + IOMMU_FAULT_REASON_OOR_ADDRESS, +}; + +/** + * Unrecoverable fault data + * @reason: reason of the fault + * @addr: offending page address + * @fetch_addr: address that caused a fetch abort, if any + * @pasid: contains process address space ID, used in shared virtual memory + * @perm: Requested permission access using by the incoming transaction + * (IOMMU_FAULT_PERM_* values) + */ +struct iommu_fault_unrecoverable { + __u32 reason; /* enum iommu_fault_reason */ +#define IOMMU_FAULT_UNRECOV_PASID_VALID (1 << 0) +#define IOMMU_FAULT_UNRECOV_PERM_VALID (1 << 1) +#define IOMMU_FAULT_UNRECOV_ADDR_VALID (1 << 2) +#define IOMMU_FAULT_UNRECOV_FETCH_ADDR_VALID (1 << 3) + __u32 flags; + __u32 pasid; + __u32 perm; + __u64 addr; + __u64 fetch_addr; +}; + +/* + * Page Request data (aka. recoverable fault data) + * @flags : encodes whether the pasid is valid and whether this + * is the last page in group + * @pasid: pasid + * @grpid: page request group index + * @perm: requested page permissions (IOMMU_FAULT_PERM_* values) + * @addr: page address + */ +struct iommu_fault_page_request { +#define IOMMU_FAULT_PAGE_REQUEST_PASID_VALID (1 << 0) +#define IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE (1 << 1) +#define IOMMU_FAULT_PAGE_REQUEST_PRIV_DATA (1 << 2) + __u32 flags; + __u32 pasid; + __u32 grpid; + __u32 perm; + __u64 addr; + __u64 private_data[2]; +}; + +/** + * struct iommu_fault - Generic fault data + * + * @type contains fault type + */ + +struct iommu_fault { + __u32 type; /* enum iommu_fault_type */ + __u32 reserved; + union { + struct iommu_fault_unrecoverable event; + struct iommu_fault_page_request prm; + }; +}; +#endif /* _UAPI_IOMMU_H */ -- 2.20.1 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm