diff options
Diffstat (limited to 'drivers/iommu/iommu-sva.c')
| -rw-r--r-- | drivers/iommu/iommu-sva.c | 125 |
1 files changed, 105 insertions, 20 deletions
diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index c3fc9201d0be..1a51cfd82808 100644 --- a/drivers/iommu/iommu-sva.c +++ b/drivers/iommu/iommu-sva.c @@ -7,9 +7,11 @@ #include <linux/sched/mm.h> #include <linux/iommu.h> -#include "iommu-sva.h" +#include "iommu-priv.h" static DEFINE_MUTEX(iommu_sva_lock); +static struct iommu_domain *iommu_sva_domain_alloc(struct device *dev, + struct mm_struct *mm); /* Allocate a PASID for the mm within range (inclusive) */ static struct iommu_mm_data *iommu_alloc_mm_data(struct mm_struct *mm, struct device *dev) @@ -61,18 +63,20 @@ static struct iommu_mm_data *iommu_alloc_mm_data(struct mm_struct *mm, struct de * reference is taken. Caller must call iommu_sva_unbind_device() * to release each reference. * - * iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA) must be called first, to - * initialize the required SVA features. - * * On error, returns an ERR_PTR value. */ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm) { + struct iommu_group *group = dev->iommu_group; + struct iommu_attach_handle *attach_handle; struct iommu_mm_data *iommu_mm; struct iommu_domain *domain; struct iommu_sva *handle; int ret; + if (!group) + return ERR_PTR(-ENODEV); + mutex_lock(&iommu_sva_lock); /* Allocate mm->pasid if necessary. */ @@ -82,6 +86,24 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm goto out_unlock; } + /* A bond already exists, just take a reference`. */ + attach_handle = iommu_attach_handle_get(group, iommu_mm->pasid, IOMMU_DOMAIN_SVA); + if (!IS_ERR(attach_handle)) { + handle = container_of(attach_handle, struct iommu_sva, handle); + if (attach_handle->domain->mm != mm) { + ret = -EBUSY; + goto out_unlock; + } + refcount_inc(&handle->users); + mutex_unlock(&iommu_sva_lock); + return handle; + } + + if (PTR_ERR(attach_handle) != -ENOENT) { + ret = PTR_ERR(attach_handle); + goto out_unlock; + } + handle = kzalloc(sizeof(*handle), GFP_KERNEL); if (!handle) { ret = -ENOMEM; @@ -90,7 +112,8 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm /* Search for an existing domain. */ list_for_each_entry(domain, &mm->iommu_mm->sva_domains, next) { - ret = iommu_attach_device_pasid(domain, dev, iommu_mm->pasid); + ret = iommu_attach_device_pasid(domain, dev, iommu_mm->pasid, + &handle->handle); if (!ret) { domain->users++; goto out; @@ -99,21 +122,22 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm /* Allocate a new domain and set it on device pasid. */ domain = iommu_sva_domain_alloc(dev, mm); - if (!domain) { - ret = -ENOMEM; + if (IS_ERR(domain)) { + ret = PTR_ERR(domain); goto out_free_handle; } - ret = iommu_attach_device_pasid(domain, dev, iommu_mm->pasid); + ret = iommu_attach_device_pasid(domain, dev, iommu_mm->pasid, + &handle->handle); if (ret) goto out_free_domain; domain->users = 1; list_add(&domain->next, &mm->iommu_mm->sva_domains); out: + refcount_set(&handle->users, 1); mutex_unlock(&iommu_sva_lock); handle->dev = dev; - handle->domain = domain; return handle; out_free_domain: @@ -136,11 +160,16 @@ EXPORT_SYMBOL_GPL(iommu_sva_bind_device); */ void iommu_sva_unbind_device(struct iommu_sva *handle) { - struct iommu_domain *domain = handle->domain; + struct iommu_domain *domain = handle->handle.domain; struct iommu_mm_data *iommu_mm = domain->mm->iommu_mm; struct device *dev = handle->dev; mutex_lock(&iommu_sva_lock); + if (!refcount_dec_and_test(&handle->users)) { + mutex_unlock(&iommu_sva_lock); + return; + } + iommu_detach_device_pasid(domain, dev, iommu_mm->pasid); if (--domain->users == 0) { list_del(&domain->next); @@ -153,21 +182,31 @@ EXPORT_SYMBOL_GPL(iommu_sva_unbind_device); u32 iommu_sva_get_pasid(struct iommu_sva *handle) { - struct iommu_domain *domain = handle->domain; + struct iommu_domain *domain = handle->handle.domain; return mm_get_enqcmd_pasid(domain->mm); } EXPORT_SYMBOL_GPL(iommu_sva_get_pasid); +void mm_pasid_drop(struct mm_struct *mm) +{ + struct iommu_mm_data *iommu_mm = mm->iommu_mm; + + if (!iommu_mm) + return; + + iommu_free_global_pasid(iommu_mm->pasid); + kfree(iommu_mm); +} + /* * I/O page fault handler for SVA */ -enum iommu_page_response_code -iommu_sva_handle_iopf(struct iommu_fault *fault, void *data) +static enum iommu_page_response_code +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; @@ -217,13 +256,59 @@ out_put_mm: return status; } -void mm_pasid_drop(struct mm_struct *mm) +static void iommu_sva_handle_iopf(struct work_struct *work) { - struct iommu_mm_data *iommu_mm = mm->iommu_mm; + struct iopf_fault *iopf; + struct iopf_group *group; + enum iommu_page_response_code status = IOMMU_PAGE_RESP_SUCCESS; + + group = container_of(work, struct iopf_group, work); + 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) + break; + + status = iommu_sva_handle_mm(&iopf->fault, + group->attach_handle->domain->mm); + } - if (!iommu_mm) - return; + iopf_group_response(group, status); + iopf_free_group(group); +} - iommu_free_global_pasid(iommu_mm->pasid); - kfree(iommu_mm); +static int iommu_sva_iopf_handler(struct iopf_group *group) +{ + struct iommu_fault_param *fault_param = group->fault_param; + + INIT_WORK(&group->work, iommu_sva_handle_iopf); + if (!queue_work(fault_param->queue->wq, &group->work)) + return -EBUSY; + + return 0; +} + +static struct iommu_domain *iommu_sva_domain_alloc(struct device *dev, + struct mm_struct *mm) +{ + const struct iommu_ops *ops = dev_iommu_ops(dev); + struct iommu_domain *domain; + + if (!ops->domain_alloc_sva) + return ERR_PTR(-EOPNOTSUPP); + + domain = ops->domain_alloc_sva(dev, mm); + if (IS_ERR(domain)) + return domain; + + domain->type = IOMMU_DOMAIN_SVA; + domain->cookie_type = IOMMU_COOKIE_SVA; + mmgrab(mm); + domain->mm = mm; + domain->owner = ops; + domain->iopf_handler = iommu_sva_iopf_handler; + + return domain; } |