iommu: Make iommu_queue_iopf() more generic

Make iommu_queue_iopf() more generic by making the iopf_group a minimal
set of iopf's that an iopf handler of domain should handle and respond
to. Add domain parameter to struct iopf_group so that the handler can
retrieve and use it directly.

Change iommu_queue_iopf() to forward groups of iopf's to the domain's
iopf handler. This is also a necessary step to decouple the sva iopf
handling code from this interface.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Tested-by: Yan Zhao <yan.y.zhao@intel.com>
Tested-by: Longfang Liu <liulongfang@huawei.com>
Link: https://lore.kernel.org/r/20240212012227.119381-10-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/io-pgfault.c b/drivers/iommu/io-pgfault.c
index c7e6bbed5c05b337bd0c834539fcd7718b4ebbb2..13cd0929e766121f99be8aa8dff8984102be810d 100644 (file)
--- a/drivers/iommu/io-pgfault.c
+++ b/drivers/iommu/io-pgfault.c
@@ -13,6 +13,9 @@
 
 #include "iommu-sva.h"
 
+enum iommu_page_response_code
+iommu_sva_handle_mm(struct iommu_fault *fault, struct mm_struct *mm);
+
 static void iopf_free_group(struct iopf_group *group)
 {
        struct iopf_fault *iopf, *next;
@@ -45,29 +48,48 @@ static void iopf_handler(struct work_struct *work)
 {
        struct iopf_fault *iopf;
        struct iopf_group *group;
-       struct iommu_domain *domain;
        enum iommu_page_response_code status = IOMMU_PAGE_RESP_SUCCESS;
 
        group = container_of(work, struct iopf_group, work);
-       domain = iommu_get_domain_for_dev_pasid(group->dev,
-                               group->last_fault.fault.prm.pasid, 0);
-       if (!domain || !domain->iopf_handler)
-               status = IOMMU_PAGE_RESP_INVALID;
-
        list_for_each_entry(iopf, &group->faults, list) {
                /*
                 * For the moment, errors are sticky: don't handle subsequent
                 * faults in the group if there is an error.
                 */
-               if (status == IOMMU_PAGE_RESP_SUCCESS)
-                       status = domain->iopf_handler(&iopf->fault,
-                                                     domain->fault_data);
+               if (status != IOMMU_PAGE_RESP_SUCCESS)
+                       break;
+
+               status = iommu_sva_handle_mm(&iopf->fault, group->domain->mm);
        }
 
        iopf_complete_group(group->dev, &group->last_fault, status);
        iopf_free_group(group);
 }
 
+static struct iommu_domain *get_domain_for_iopf(struct device *dev,
+                                               struct iommu_fault *fault)
+{
+       struct iommu_domain *domain;
+
+       if (fault->prm.flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID) {
+               domain = iommu_get_domain_for_dev_pasid(dev, fault->prm.pasid, 0);
+               if (IS_ERR(domain))
+                       domain = NULL;
+       } else {
+               domain = iommu_get_domain_for_dev(dev);
+       }
+
+       if (!domain || !domain->iopf_handler) {
+               dev_warn_ratelimited(dev,
+                       "iopf (pasid %d) without domain attached or handler installed\n",
+                        fault->prm.pasid);
+
+               return NULL;
+       }
+
+       return domain;
+}
+
 /**
  * iommu_queue_iopf - IO Page Fault handler
  * @fault: fault event
@@ -112,6 +134,7 @@ int iommu_queue_iopf(struct iommu_fault *fault, struct device *dev)
 {
        int ret;
        struct iopf_group *group;
+       struct iommu_domain *domain;
        struct iopf_fault *iopf, *next;
        struct iommu_fault_param *iopf_param;
        struct dev_iommu *param = dev->iommu;
@@ -143,6 +166,12 @@ int iommu_queue_iopf(struct iommu_fault *fault, struct device *dev)
                return 0;
        }
 
+       domain = get_domain_for_iopf(dev, fault);
+       if (!domain) {
+               ret = -EINVAL;
+               goto cleanup_partial;
+       }
+
        group = kzalloc(sizeof(*group), GFP_KERNEL);
        if (!group) {
                /*
@@ -157,8 +186,8 @@ int iommu_queue_iopf(struct iommu_fault *fault, struct device *dev)
        group->dev = dev;
        group->last_fault.fault = *fault;
        INIT_LIST_HEAD(&group->faults);
+       group->domain = domain;
        list_add(&group->last_fault.list, &group->faults);
-       INIT_WORK(&group->work, iopf_handler);
 
        /* See if we have partial faults for this group */
        list_for_each_entry_safe(iopf, next, &iopf_param->partial, list) {
@@ -167,9 +196,13 @@ int iommu_queue_iopf(struct iommu_fault *fault, struct device *dev)
                        list_move(&iopf->list, &group->faults);
        }
 
-       queue_work(iopf_param->queue->wq, &group->work);
-       return 0;
+       mutex_unlock(&iopf_param->lock);
+       ret = domain->iopf_handler(group);
+       mutex_lock(&iopf_param->lock);
+       if (ret)
+               iopf_free_group(group);
 
+       return ret;
 cleanup_partial:
        list_for_each_entry_safe(iopf, next, &iopf_param->partial, list) {
                if (iopf->fault.prm.grpid == fault->prm.grpid) {
@@ -181,6 +214,17 @@ cleanup_partial:
 }
 EXPORT_SYMBOL_GPL(iommu_queue_iopf);
 
+int iommu_sva_handle_iopf(struct iopf_group *group)
+{
+       struct iommu_fault_param *fault_param = group->dev->iommu->fault_param;
+
+       INIT_WORK(&group->work, iopf_handler);
+       if (!queue_work(fault_param->queue->wq, &group->work))
+               return -EBUSY;
+
+       return 0;
+}
+
 /**
  * iopf_queue_flush_dev - Ensure that all queued faults have been processed
  * @dev: the endpoint whose faults need to be flushed.

diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
index c3fc9201d0be97e59395750cda0fc29940c0b844..fcae7308fcb7e028fbff50a92ffea355363a771f 100644 (file)
--- a/drivers/iommu/iommu-sva.c
+++ b/drivers/iommu/iommu-sva.c
@@ -163,11 +163,10 @@ EXPORT_SYMBOL_GPL(iommu_sva_get_pasid);
  * I/O page fault handler for SVA
  */
 enum iommu_page_response_code
-iommu_sva_handle_iopf(struct iommu_fault *fault, void *data)
+iommu_sva_handle_mm(struct iommu_fault *fault, struct mm_struct *mm)
 {
        vm_fault_t ret;
        struct vm_area_struct *vma;
-       struct mm_struct *mm = data;
        unsigned int access_flags = 0;
        unsigned int fault_flags = FAULT_FLAG_REMOTE;
        struct iommu_fault_page_request *prm = &fault->prm;

diff --git a/drivers/iommu/iommu-sva.h b/drivers/iommu/iommu-sva.h
index de7819c796ceefc4787fba6995a0a984797a7516..27c8da115b418e0aaef1b396ef2c22b1e4646bda 100644 (file)
--- a/drivers/iommu/iommu-sva.h
+++ b/drivers/iommu/iommu-sva.h
@@ -22,8 +22,7 @@ int iopf_queue_flush_dev(struct device *dev);
 struct iopf_queue *iopf_queue_alloc(const char *name);
 void iopf_queue_free(struct iopf_queue *queue);
 int iopf_queue_discard_partial(struct iopf_queue *queue);
-enum iommu_page_response_code
-iommu_sva_handle_iopf(struct iommu_fault *fault, void *data);
+int iommu_sva_handle_iopf(struct iopf_group *group);
 
 #else /* CONFIG_IOMMU_SVA */
 static inline int iommu_queue_iopf(struct iommu_fault *fault, struct device *dev)
@@ -62,8 +61,7 @@ static inline int iopf_queue_discard_partial(struct iopf_queue *queue)
        return -ENODEV;
 }
 
-static inline enum iommu_page_response_code
-iommu_sva_handle_iopf(struct iommu_fault *fault, void *data)
+static inline int iommu_sva_handle_iopf(struct iopf_group *group)
 {
        return IOMMU_PAGE_RESP_INVALID;
 }

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index c9d4f175f121cb1c71199d83978aea82b7e84a35..791f183a988e26e28434b5bb167460781776e012 100644 (file)
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -130,6 +130,7 @@ struct iopf_group {
        struct list_head faults;
        struct work_struct work;
        struct device *dev;
+       struct iommu_domain *domain;
 };
 
 /**
@@ -209,8 +210,7 @@ struct iommu_domain {
        unsigned long pgsize_bitmap;    /* Bitmap of page sizes in use */
        struct iommu_domain_geometry geometry;
        struct iommu_dma_cookie *iova_cookie;
-       enum iommu_page_response_code (*iopf_handler)(struct iommu_fault *fault,
-                                                     void *data);
+       int (*iopf_handler)(struct iopf_group *group);
        void *fault_data;
        union {
                struct {