diff options
Diffstat (limited to 'drivers/iommu/io-pgfault.c')
-rw-r--r-- | drivers/iommu/io-pgfault.c | 132 |
1 files changed, 70 insertions, 62 deletions
diff --git a/drivers/iommu/io-pgfault.c b/drivers/iommu/io-pgfault.c index 05e49e2e6a52..6a325bff8164 100644 --- a/drivers/iommu/io-pgfault.c +++ b/drivers/iommu/io-pgfault.c @@ -39,7 +39,7 @@ static void iopf_put_dev_fault_param(struct iommu_fault_param *fault_param) kfree_rcu(fault_param, rcu); } -void iopf_free_group(struct iopf_group *group) +static void __iopf_free_group(struct iopf_group *group) { struct iopf_fault *iopf, *next; @@ -50,6 +50,11 @@ void iopf_free_group(struct iopf_group *group) /* Pair with iommu_report_device_fault(). */ iopf_put_dev_fault_param(group->fault_param); +} + +void iopf_free_group(struct iopf_group *group) +{ + __iopf_free_group(group); kfree(group); } EXPORT_SYMBOL_GPL(iopf_free_group); @@ -97,14 +102,49 @@ static int report_partial_fault(struct iommu_fault_param *fault_param, return 0; } +static struct iopf_group *iopf_group_alloc(struct iommu_fault_param *iopf_param, + struct iopf_fault *evt, + struct iopf_group *abort_group) +{ + struct iopf_fault *iopf, *next; + struct iopf_group *group; + + group = kzalloc(sizeof(*group), GFP_KERNEL); + if (!group) { + /* + * We always need to construct the group as we need it to abort + * the request at the driver if it can't be handled. + */ + group = abort_group; + } + + group->fault_param = iopf_param; + group->last_fault.fault = evt->fault; + INIT_LIST_HEAD(&group->faults); + INIT_LIST_HEAD(&group->pending_node); + list_add(&group->last_fault.list, &group->faults); + + /* See if we have partial faults for this group */ + mutex_lock(&iopf_param->lock); + list_for_each_entry_safe(iopf, next, &iopf_param->partial, list) { + if (iopf->fault.prm.grpid == evt->fault.prm.grpid) + /* Insert *before* the last fault */ + list_move(&iopf->list, &group->faults); + } + list_add(&group->pending_node, &iopf_param->faults); + mutex_unlock(&iopf_param->lock); + + return group; +} + /** * iommu_report_device_fault() - Report fault event to device driver * @dev: the device * @evt: fault event data * * Called by IOMMU drivers when a fault is detected, typically in a threaded IRQ - * handler. When this function fails and the fault is recoverable, it is the - * caller's responsibility to complete the fault. + * handler. If this function fails then ops->page_response() was called to + * complete evt if required. * * This module doesn't handle PCI PASID Stop Marker; IOMMU drivers must discard * them before reporting faults. A PASID Stop Marker (LRW = 0b100) doesn't @@ -143,22 +183,18 @@ int iommu_report_device_fault(struct device *dev, struct iopf_fault *evt) { struct iommu_fault *fault = &evt->fault; struct iommu_fault_param *iopf_param; - struct iopf_fault *iopf, *next; - struct iommu_domain *domain; + struct iopf_group abort_group = {}; struct iopf_group *group; int ret; - if (fault->type != IOMMU_FAULT_PAGE_REQ) - return -EOPNOTSUPP; - iopf_param = iopf_get_dev_fault_param(dev); - if (!iopf_param) + if (WARN_ON(!iopf_param)) return -ENODEV; if (!(fault->prm.flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE)) { ret = report_partial_fault(iopf_param, fault); iopf_put_dev_fault_param(iopf_param); - + /* A request that is not the last does not need to be ack'd */ return ret; } @@ -170,56 +206,33 @@ int iommu_report_device_fault(struct device *dev, struct iopf_fault *evt) * will send a response to the hardware. We need to clean up before * leaving, otherwise partial faults will be stuck. */ - domain = get_domain_for_iopf(dev, fault); - if (!domain) { - ret = -EINVAL; - goto cleanup_partial; - } - - group = kzalloc(sizeof(*group), GFP_KERNEL); - if (!group) { + group = iopf_group_alloc(iopf_param, evt, &abort_group); + if (group == &abort_group) { ret = -ENOMEM; - goto cleanup_partial; + goto err_abort; } - group->fault_param = iopf_param; - group->last_fault.fault = *fault; - INIT_LIST_HEAD(&group->faults); - INIT_LIST_HEAD(&group->pending_node); - group->domain = domain; - list_add(&group->last_fault.list, &group->faults); - - /* See if we have partial faults for this group */ - mutex_lock(&iopf_param->lock); - list_for_each_entry_safe(iopf, next, &iopf_param->partial, list) { - if (iopf->fault.prm.grpid == fault->prm.grpid) - /* Insert *before* the last fault */ - list_move(&iopf->list, &group->faults); - } - list_add(&group->pending_node, &iopf_param->faults); - mutex_unlock(&iopf_param->lock); - - ret = domain->iopf_handler(group); - if (ret) { - mutex_lock(&iopf_param->lock); - list_del_init(&group->pending_node); - mutex_unlock(&iopf_param->lock); - iopf_free_group(group); + group->domain = get_domain_for_iopf(dev, fault); + if (!group->domain) { + ret = -EINVAL; + goto err_abort; } - return ret; - -cleanup_partial: - mutex_lock(&iopf_param->lock); - list_for_each_entry_safe(iopf, next, &iopf_param->partial, list) { - if (iopf->fault.prm.grpid == fault->prm.grpid) { - list_del(&iopf->list); - kfree(iopf); - } - } - mutex_unlock(&iopf_param->lock); - iopf_put_dev_fault_param(iopf_param); + /* + * On success iopf_handler must call iopf_group_response() and + * iopf_free_group() + */ + ret = group->domain->iopf_handler(group); + if (ret) + goto err_abort; + return 0; +err_abort: + iopf_group_response(group, IOMMU_PAGE_RESP_FAILURE); + if (group == &abort_group) + __iopf_free_group(group); + else + iopf_free_group(group); return ret; } EXPORT_SYMBOL_GPL(iommu_report_device_fault); @@ -259,11 +272,9 @@ EXPORT_SYMBOL_GPL(iopf_queue_flush_dev); * iopf_group_response - Respond a group of page faults * @group: the group of faults with the same group id * @status: the response code - * - * Return 0 on success and <0 on error. */ -int iopf_group_response(struct iopf_group *group, - enum iommu_page_response_code status) +void iopf_group_response(struct iopf_group *group, + enum iommu_page_response_code status) { struct iommu_fault_param *fault_param = group->fault_param; struct iopf_fault *iopf = &group->last_fault; @@ -274,17 +285,14 @@ int iopf_group_response(struct iopf_group *group, .grpid = iopf->fault.prm.grpid, .code = status, }; - int ret = -EINVAL; /* Only send response if there is a fault report pending */ mutex_lock(&fault_param->lock); if (!list_empty(&group->pending_node)) { - ret = ops->page_response(dev, &group->last_fault, &resp); + ops->page_response(dev, &group->last_fault, &resp); list_del_init(&group->pending_node); } mutex_unlock(&fault_param->lock); - - return ret; } EXPORT_SYMBOL_GPL(iopf_group_response); |