diff options
author | Lu Baolu <baolu.lu@linux.intel.com> | 2024-07-02 14:34:37 +0800 |
---|---|---|
committer | Will Deacon <will@kernel.org> | 2024-07-04 13:46:18 +0100 |
commit | 06cdcc32d65759d42c6340700796e2906045b6a5 (patch) | |
tree | 771b01a3c93cecd2fd6401c86379fa5a34937117 /drivers | |
parent | 3e7f57d1ef3f5fbed58974fae38d35e430f57d35 (diff) | |
download | lwn-06cdcc32d65759d42c6340700796e2906045b6a5.tar.gz lwn-06cdcc32d65759d42c6340700796e2906045b6a5.zip |
iommu: Add attach handle to struct iopf_group
Previously, the domain that a page fault targets is stored in an
iopf_group, which represents a minimal set of page faults. With the
introduction of attach handle, replace the domain with the handle
so that the fault handler can obtain more information as needed
when handling the faults.
iommu_report_device_fault() is currently used for SVA page faults,
which handles the page fault in an internal cycle. The domain is retrieved
with iommu_get_domain_for_dev_pasid() if the pasid in the fault message
is valid. This doesn't work in IOMMUFD case, where if the pasid table of
a device is wholly managed by user space, there is no domain attached to
the PASID of the device, and all page faults are forwarded through a
NESTING domain attaching to RID.
Add a static flag in iommu ops, which indicates if the IOMMU driver
supports user-managed PASID tables. In the iopf deliver path, if no
attach handle found for the iopf PASID, roll back to RID domain when
the IOMMU driver supports this capability.
iommu_get_domain_for_dev_pasid() is no longer used and can be removed.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20240702063444.105814-4-baolu.lu@linux.intel.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/iommu/io-pgfault.c | 61 | ||||
-rw-r--r-- | drivers/iommu/iommu-sva.c | 3 | ||||
-rw-r--r-- | drivers/iommu/iommu.c | 39 |
3 files changed, 36 insertions, 67 deletions
diff --git a/drivers/iommu/io-pgfault.c b/drivers/iommu/io-pgfault.c index 06d78fcc79fd..7c9011992d3f 100644 --- a/drivers/iommu/io-pgfault.c +++ b/drivers/iommu/io-pgfault.c @@ -59,30 +59,6 @@ void iopf_free_group(struct iopf_group *group) } EXPORT_SYMBOL_GPL(iopf_free_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; -} - /* Non-last request of a group. Postpone until the last one. */ static int report_partial_fault(struct iommu_fault_param *fault_param, struct iommu_fault *fault) @@ -206,20 +182,51 @@ void iommu_report_device_fault(struct device *dev, struct iopf_fault *evt) if (group == &abort_group) goto err_abort; - group->domain = get_domain_for_iopf(dev, fault); - if (!group->domain) + if (fault->prm.flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID) { + group->attach_handle = iommu_attach_handle_get(dev->iommu_group, + fault->prm.pasid, + 0); + if (IS_ERR(group->attach_handle)) { + const struct iommu_ops *ops = dev_iommu_ops(dev); + + if (!ops->user_pasid_table) + goto err_abort; + + /* + * The iommu driver for this device supports user- + * managed PASID table. Therefore page faults for + * any PASID should go through the NESTING domain + * attached to the device RID. + */ + group->attach_handle = + iommu_attach_handle_get(dev->iommu_group, + IOMMU_NO_PASID, + IOMMU_DOMAIN_NESTED); + if (IS_ERR(group->attach_handle)) + goto err_abort; + } + } else { + group->attach_handle = + iommu_attach_handle_get(dev->iommu_group, IOMMU_NO_PASID, 0); + if (IS_ERR(group->attach_handle)) + goto err_abort; + } + + if (!group->attach_handle->domain->iopf_handler) goto err_abort; /* * On success iopf_handler must call iopf_group_response() and * iopf_free_group() */ - if (group->domain->iopf_handler(group)) + if (group->attach_handle->domain->iopf_handler(group)) goto err_abort; return; err_abort: + dev_warn_ratelimited(dev, "iopf with pasid %d aborted\n", + fault->prm.pasid); iopf_group_response(group, IOMMU_PAGE_RESP_FAILURE); if (group == &abort_group) __iopf_free_group(group); diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index 9b7f62517419..69cde094440e 100644 --- a/drivers/iommu/iommu-sva.c +++ b/drivers/iommu/iommu-sva.c @@ -272,7 +272,8 @@ static void iommu_sva_handle_iopf(struct work_struct *work) if (status != IOMMU_PAGE_RESP_SUCCESS) break; - status = iommu_sva_handle_mm(&iopf->fault, group->domain->mm); + status = iommu_sva_handle_mm(&iopf->fault, + group->attach_handle->domain->mm); } iopf_group_response(group, status); diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 7890bd21dff6..5a7e874abb36 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3421,45 +3421,6 @@ void iommu_detach_device_pasid(struct iommu_domain *domain, struct device *dev, } EXPORT_SYMBOL_GPL(iommu_detach_device_pasid); -/* - * iommu_get_domain_for_dev_pasid() - Retrieve domain for @pasid of @dev - * @dev: the queried device - * @pasid: the pasid of the device - * @type: matched domain type, 0 for any match - * - * This is a variant of iommu_get_domain_for_dev(). It returns the existing - * domain attached to pasid of a device. Callers must hold a lock around this - * function, and both iommu_attach/detach_dev_pasid() whenever a domain of - * type is being manipulated. This API does not internally resolve races with - * attach/detach. - * - * Return: attached domain on success, NULL otherwise. - */ -struct iommu_domain *iommu_get_domain_for_dev_pasid(struct device *dev, - ioasid_t pasid, - unsigned int type) -{ - /* Caller must be a probed driver on dev */ - struct iommu_group *group = dev->iommu_group; - struct iommu_attach_handle *handle; - struct iommu_domain *domain = NULL; - - if (!group) - return NULL; - - xa_lock(&group->pasid_array); - handle = xa_load(&group->pasid_array, pasid); - if (handle) - domain = handle->domain; - - if (type && domain && domain->type != type) - domain = NULL; - xa_unlock(&group->pasid_array); - - return domain; -} -EXPORT_SYMBOL_GPL(iommu_get_domain_for_dev_pasid); - ioasid_t iommu_alloc_global_pasid(struct device *dev) { int ret; |