1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES
4 */
5 #include <linux/iommu.h>
6 #include <uapi/linux/iommufd.h>
7
8 #include "../iommu-priv.h"
9 #include "iommufd_private.h"
10
__iommufd_hwpt_destroy(struct iommufd_hw_pagetable * hwpt)11 static void __iommufd_hwpt_destroy(struct iommufd_hw_pagetable *hwpt)
12 {
13 if (hwpt->domain)
14 iommu_domain_free(hwpt->domain);
15
16 if (hwpt->fault)
17 refcount_dec(&hwpt->fault->obj.users);
18 }
19
iommufd_hwpt_paging_destroy(struct iommufd_object * obj)20 void iommufd_hwpt_paging_destroy(struct iommufd_object *obj)
21 {
22 struct iommufd_hwpt_paging *hwpt_paging =
23 container_of(obj, struct iommufd_hwpt_paging, common.obj);
24
25 if (!list_empty(&hwpt_paging->hwpt_item)) {
26 mutex_lock(&hwpt_paging->ioas->mutex);
27 list_del(&hwpt_paging->hwpt_item);
28 mutex_unlock(&hwpt_paging->ioas->mutex);
29
30 iopt_table_remove_domain(&hwpt_paging->ioas->iopt,
31 hwpt_paging->common.domain);
32 }
33
34 __iommufd_hwpt_destroy(&hwpt_paging->common);
35 refcount_dec(&hwpt_paging->ioas->obj.users);
36 }
37
iommufd_hwpt_paging_abort(struct iommufd_object * obj)38 void iommufd_hwpt_paging_abort(struct iommufd_object *obj)
39 {
40 struct iommufd_hwpt_paging *hwpt_paging =
41 container_of(obj, struct iommufd_hwpt_paging, common.obj);
42
43 /* The ioas->mutex must be held until finalize is called. */
44 lockdep_assert_held(&hwpt_paging->ioas->mutex);
45
46 if (!list_empty(&hwpt_paging->hwpt_item)) {
47 list_del_init(&hwpt_paging->hwpt_item);
48 iopt_table_remove_domain(&hwpt_paging->ioas->iopt,
49 hwpt_paging->common.domain);
50 }
51 iommufd_hwpt_paging_destroy(obj);
52 }
53
iommufd_hwpt_nested_destroy(struct iommufd_object * obj)54 void iommufd_hwpt_nested_destroy(struct iommufd_object *obj)
55 {
56 struct iommufd_hwpt_nested *hwpt_nested =
57 container_of(obj, struct iommufd_hwpt_nested, common.obj);
58
59 __iommufd_hwpt_destroy(&hwpt_nested->common);
60 refcount_dec(&hwpt_nested->parent->common.obj.users);
61 }
62
iommufd_hwpt_nested_abort(struct iommufd_object * obj)63 void iommufd_hwpt_nested_abort(struct iommufd_object *obj)
64 {
65 iommufd_hwpt_nested_destroy(obj);
66 }
67
68 static int
iommufd_hwpt_paging_enforce_cc(struct iommufd_hwpt_paging * hwpt_paging)69 iommufd_hwpt_paging_enforce_cc(struct iommufd_hwpt_paging *hwpt_paging)
70 {
71 struct iommu_domain *paging_domain = hwpt_paging->common.domain;
72
73 if (hwpt_paging->enforce_cache_coherency)
74 return 0;
75
76 if (paging_domain->ops->enforce_cache_coherency)
77 hwpt_paging->enforce_cache_coherency =
78 paging_domain->ops->enforce_cache_coherency(
79 paging_domain);
80 if (!hwpt_paging->enforce_cache_coherency)
81 return -EINVAL;
82 return 0;
83 }
84
85 /**
86 * iommufd_hwpt_paging_alloc() - Get a PAGING iommu_domain for a device
87 * @ictx: iommufd context
88 * @ioas: IOAS to associate the domain with
89 * @idev: Device to get an iommu_domain for
90 * @flags: Flags from userspace
91 * @immediate_attach: True if idev should be attached to the hwpt
92 * @user_data: The user provided driver specific data describing the domain to
93 * create
94 *
95 * Allocate a new iommu_domain and return it as a hw_pagetable. The HWPT
96 * will be linked to the given ioas and upon return the underlying iommu_domain
97 * is fully popoulated.
98 *
99 * The caller must hold the ioas->mutex until after
100 * iommufd_object_abort_and_destroy() or iommufd_object_finalize() is called on
101 * the returned hwpt.
102 */
103 struct iommufd_hwpt_paging *
iommufd_hwpt_paging_alloc(struct iommufd_ctx * ictx,struct iommufd_ioas * ioas,struct iommufd_device * idev,u32 flags,bool immediate_attach,const struct iommu_user_data * user_data)104 iommufd_hwpt_paging_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
105 struct iommufd_device *idev, u32 flags,
106 bool immediate_attach,
107 const struct iommu_user_data *user_data)
108 {
109 const u32 valid_flags = IOMMU_HWPT_ALLOC_NEST_PARENT |
110 IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
111 const struct iommu_ops *ops = dev_iommu_ops(idev->dev);
112 struct iommufd_hwpt_paging *hwpt_paging;
113 struct iommufd_hw_pagetable *hwpt;
114 int rc;
115
116 lockdep_assert_held(&ioas->mutex);
117
118 if ((flags || user_data) && !ops->domain_alloc_user)
119 return ERR_PTR(-EOPNOTSUPP);
120 if (flags & ~valid_flags)
121 return ERR_PTR(-EOPNOTSUPP);
122 if ((flags & IOMMU_HWPT_ALLOC_DIRTY_TRACKING) &&
123 !device_iommu_capable(idev->dev, IOMMU_CAP_DIRTY_TRACKING))
124 return ERR_PTR(-EOPNOTSUPP);
125
126 hwpt_paging = __iommufd_object_alloc(
127 ictx, hwpt_paging, IOMMUFD_OBJ_HWPT_PAGING, common.obj);
128 if (IS_ERR(hwpt_paging))
129 return ERR_CAST(hwpt_paging);
130 hwpt = &hwpt_paging->common;
131
132 INIT_LIST_HEAD(&hwpt_paging->hwpt_item);
133 /* Pairs with iommufd_hw_pagetable_destroy() */
134 refcount_inc(&ioas->obj.users);
135 hwpt_paging->ioas = ioas;
136 hwpt_paging->nest_parent = flags & IOMMU_HWPT_ALLOC_NEST_PARENT;
137
138 if (ops->domain_alloc_user) {
139 hwpt->domain = ops->domain_alloc_user(idev->dev, flags, NULL,
140 user_data);
141 if (IS_ERR(hwpt->domain)) {
142 rc = PTR_ERR(hwpt->domain);
143 hwpt->domain = NULL;
144 goto out_abort;
145 }
146 hwpt->domain->owner = ops;
147 } else {
148 hwpt->domain = iommu_paging_domain_alloc(idev->dev);
149 if (IS_ERR(hwpt->domain)) {
150 rc = PTR_ERR(hwpt->domain);
151 hwpt->domain = NULL;
152 goto out_abort;
153 }
154 }
155
156 /*
157 * Set the coherency mode before we do iopt_table_add_domain() as some
158 * iommus have a per-PTE bit that controls it and need to decide before
159 * doing any maps. It is an iommu driver bug to report
160 * IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail enforce_cache_coherency on
161 * a new domain.
162 *
163 * The cache coherency mode must be configured here and unchanged later.
164 * Note that a HWPT (non-CC) created for a device (non-CC) can be later
165 * reused by another device (either non-CC or CC). However, A HWPT (CC)
166 * created for a device (CC) cannot be reused by another device (non-CC)
167 * but only devices (CC). Instead user space in this case would need to
168 * allocate a separate HWPT (non-CC).
169 */
170 if (idev->enforce_cache_coherency) {
171 rc = iommufd_hwpt_paging_enforce_cc(hwpt_paging);
172 if (WARN_ON(rc))
173 goto out_abort;
174 }
175
176 /*
177 * immediate_attach exists only to accommodate iommu drivers that cannot
178 * directly allocate a domain. These drivers do not finish creating the
179 * domain until attach is completed. Thus we must have this call
180 * sequence. Once those drivers are fixed this should be removed.
181 */
182 if (immediate_attach) {
183 rc = iommufd_hw_pagetable_attach(hwpt, idev);
184 if (rc)
185 goto out_abort;
186 }
187
188 rc = iopt_table_add_domain(&ioas->iopt, hwpt->domain);
189 if (rc)
190 goto out_detach;
191 list_add_tail(&hwpt_paging->hwpt_item, &ioas->hwpt_list);
192 return hwpt_paging;
193
194 out_detach:
195 if (immediate_attach)
196 iommufd_hw_pagetable_detach(idev);
197 out_abort:
198 iommufd_object_abort_and_destroy(ictx, &hwpt->obj);
199 return ERR_PTR(rc);
200 }
201
202 /**
203 * iommufd_hwpt_nested_alloc() - Get a NESTED iommu_domain for a device
204 * @ictx: iommufd context
205 * @parent: Parent PAGING-type hwpt to associate the domain with
206 * @idev: Device to get an iommu_domain for
207 * @flags: Flags from userspace
208 * @user_data: user_data pointer. Must be valid
209 *
210 * Allocate a new iommu_domain (must be IOMMU_DOMAIN_NESTED) and return it as
211 * a NESTED hw_pagetable. The given parent PAGING-type hwpt must be capable of
212 * being a parent.
213 */
214 static struct iommufd_hwpt_nested *
iommufd_hwpt_nested_alloc(struct iommufd_ctx * ictx,struct iommufd_hwpt_paging * parent,struct iommufd_device * idev,u32 flags,const struct iommu_user_data * user_data)215 iommufd_hwpt_nested_alloc(struct iommufd_ctx *ictx,
216 struct iommufd_hwpt_paging *parent,
217 struct iommufd_device *idev, u32 flags,
218 const struct iommu_user_data *user_data)
219 {
220 const struct iommu_ops *ops = dev_iommu_ops(idev->dev);
221 struct iommufd_hwpt_nested *hwpt_nested;
222 struct iommufd_hw_pagetable *hwpt;
223 int rc;
224
225 if ((flags & ~IOMMU_HWPT_FAULT_ID_VALID) ||
226 !user_data->len || !ops->domain_alloc_user)
227 return ERR_PTR(-EOPNOTSUPP);
228 if (parent->auto_domain || !parent->nest_parent)
229 return ERR_PTR(-EINVAL);
230
231 hwpt_nested = __iommufd_object_alloc(
232 ictx, hwpt_nested, IOMMUFD_OBJ_HWPT_NESTED, common.obj);
233 if (IS_ERR(hwpt_nested))
234 return ERR_CAST(hwpt_nested);
235 hwpt = &hwpt_nested->common;
236
237 refcount_inc(&parent->common.obj.users);
238 hwpt_nested->parent = parent;
239
240 hwpt->domain = ops->domain_alloc_user(idev->dev,
241 flags & ~IOMMU_HWPT_FAULT_ID_VALID,
242 parent->common.domain, user_data);
243 if (IS_ERR(hwpt->domain)) {
244 rc = PTR_ERR(hwpt->domain);
245 hwpt->domain = NULL;
246 goto out_abort;
247 }
248 hwpt->domain->owner = ops;
249
250 if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED ||
251 !hwpt->domain->ops->cache_invalidate_user)) {
252 rc = -EINVAL;
253 goto out_abort;
254 }
255 return hwpt_nested;
256
257 out_abort:
258 iommufd_object_abort_and_destroy(ictx, &hwpt->obj);
259 return ERR_PTR(rc);
260 }
261
iommufd_hwpt_alloc(struct iommufd_ucmd * ucmd)262 int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
263 {
264 struct iommu_hwpt_alloc *cmd = ucmd->cmd;
265 const struct iommu_user_data user_data = {
266 .type = cmd->data_type,
267 .uptr = u64_to_user_ptr(cmd->data_uptr),
268 .len = cmd->data_len,
269 };
270 struct iommufd_hw_pagetable *hwpt;
271 struct iommufd_ioas *ioas = NULL;
272 struct iommufd_object *pt_obj;
273 struct iommufd_device *idev;
274 int rc;
275
276 if (cmd->__reserved)
277 return -EOPNOTSUPP;
278 if ((cmd->data_type == IOMMU_HWPT_DATA_NONE && cmd->data_len) ||
279 (cmd->data_type != IOMMU_HWPT_DATA_NONE && !cmd->data_len))
280 return -EINVAL;
281
282 idev = iommufd_get_device(ucmd, cmd->dev_id);
283 if (IS_ERR(idev))
284 return PTR_ERR(idev);
285
286 pt_obj = iommufd_get_object(ucmd->ictx, cmd->pt_id, IOMMUFD_OBJ_ANY);
287 if (IS_ERR(pt_obj)) {
288 rc = -EINVAL;
289 goto out_put_idev;
290 }
291
292 if (pt_obj->type == IOMMUFD_OBJ_IOAS) {
293 struct iommufd_hwpt_paging *hwpt_paging;
294
295 ioas = container_of(pt_obj, struct iommufd_ioas, obj);
296 mutex_lock(&ioas->mutex);
297 hwpt_paging = iommufd_hwpt_paging_alloc(
298 ucmd->ictx, ioas, idev, cmd->flags, false,
299 user_data.len ? &user_data : NULL);
300 if (IS_ERR(hwpt_paging)) {
301 rc = PTR_ERR(hwpt_paging);
302 goto out_unlock;
303 }
304 hwpt = &hwpt_paging->common;
305 } else if (pt_obj->type == IOMMUFD_OBJ_HWPT_PAGING) {
306 struct iommufd_hwpt_nested *hwpt_nested;
307
308 hwpt_nested = iommufd_hwpt_nested_alloc(
309 ucmd->ictx,
310 container_of(pt_obj, struct iommufd_hwpt_paging,
311 common.obj),
312 idev, cmd->flags, &user_data);
313 if (IS_ERR(hwpt_nested)) {
314 rc = PTR_ERR(hwpt_nested);
315 goto out_unlock;
316 }
317 hwpt = &hwpt_nested->common;
318 } else {
319 rc = -EINVAL;
320 goto out_put_pt;
321 }
322
323 if (cmd->flags & IOMMU_HWPT_FAULT_ID_VALID) {
324 struct iommufd_fault *fault;
325
326 fault = iommufd_get_fault(ucmd, cmd->fault_id);
327 if (IS_ERR(fault)) {
328 rc = PTR_ERR(fault);
329 goto out_hwpt;
330 }
331 hwpt->fault = fault;
332 hwpt->domain->iopf_handler = iommufd_fault_iopf_handler;
333 hwpt->domain->fault_data = hwpt;
334 refcount_inc(&fault->obj.users);
335 iommufd_put_object(ucmd->ictx, &fault->obj);
336 }
337
338 cmd->out_hwpt_id = hwpt->obj.id;
339 rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
340 if (rc)
341 goto out_hwpt;
342 iommufd_object_finalize(ucmd->ictx, &hwpt->obj);
343 goto out_unlock;
344
345 out_hwpt:
346 iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj);
347 out_unlock:
348 if (ioas)
349 mutex_unlock(&ioas->mutex);
350 out_put_pt:
351 iommufd_put_object(ucmd->ictx, pt_obj);
352 out_put_idev:
353 iommufd_put_object(ucmd->ictx, &idev->obj);
354 return rc;
355 }
356
iommufd_hwpt_set_dirty_tracking(struct iommufd_ucmd * ucmd)357 int iommufd_hwpt_set_dirty_tracking(struct iommufd_ucmd *ucmd)
358 {
359 struct iommu_hwpt_set_dirty_tracking *cmd = ucmd->cmd;
360 struct iommufd_hwpt_paging *hwpt_paging;
361 struct iommufd_ioas *ioas;
362 int rc = -EOPNOTSUPP;
363 bool enable;
364
365 if (cmd->flags & ~IOMMU_HWPT_DIRTY_TRACKING_ENABLE)
366 return rc;
367
368 hwpt_paging = iommufd_get_hwpt_paging(ucmd, cmd->hwpt_id);
369 if (IS_ERR(hwpt_paging))
370 return PTR_ERR(hwpt_paging);
371
372 ioas = hwpt_paging->ioas;
373 enable = cmd->flags & IOMMU_HWPT_DIRTY_TRACKING_ENABLE;
374
375 rc = iopt_set_dirty_tracking(&ioas->iopt, hwpt_paging->common.domain,
376 enable);
377
378 iommufd_put_object(ucmd->ictx, &hwpt_paging->common.obj);
379 return rc;
380 }
381
iommufd_hwpt_get_dirty_bitmap(struct iommufd_ucmd * ucmd)382 int iommufd_hwpt_get_dirty_bitmap(struct iommufd_ucmd *ucmd)
383 {
384 struct iommu_hwpt_get_dirty_bitmap *cmd = ucmd->cmd;
385 struct iommufd_hwpt_paging *hwpt_paging;
386 struct iommufd_ioas *ioas;
387 int rc = -EOPNOTSUPP;
388
389 if ((cmd->flags & ~(IOMMU_HWPT_GET_DIRTY_BITMAP_NO_CLEAR)) ||
390 cmd->__reserved)
391 return -EOPNOTSUPP;
392
393 hwpt_paging = iommufd_get_hwpt_paging(ucmd, cmd->hwpt_id);
394 if (IS_ERR(hwpt_paging))
395 return PTR_ERR(hwpt_paging);
396
397 ioas = hwpt_paging->ioas;
398 rc = iopt_read_and_clear_dirty_data(
399 &ioas->iopt, hwpt_paging->common.domain, cmd->flags, cmd);
400
401 iommufd_put_object(ucmd->ictx, &hwpt_paging->common.obj);
402 return rc;
403 }
404
iommufd_hwpt_invalidate(struct iommufd_ucmd * ucmd)405 int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
406 {
407 struct iommu_hwpt_invalidate *cmd = ucmd->cmd;
408 struct iommu_user_data_array data_array = {
409 .type = cmd->data_type,
410 .uptr = u64_to_user_ptr(cmd->data_uptr),
411 .entry_len = cmd->entry_len,
412 .entry_num = cmd->entry_num,
413 };
414 struct iommufd_hw_pagetable *hwpt;
415 u32 done_num = 0;
416 int rc;
417
418 if (cmd->__reserved) {
419 rc = -EOPNOTSUPP;
420 goto out;
421 }
422
423 if (cmd->entry_num && (!cmd->data_uptr || !cmd->entry_len)) {
424 rc = -EINVAL;
425 goto out;
426 }
427
428 hwpt = iommufd_get_hwpt_nested(ucmd, cmd->hwpt_id);
429 if (IS_ERR(hwpt)) {
430 rc = PTR_ERR(hwpt);
431 goto out;
432 }
433
434 rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,
435 &data_array);
436 done_num = data_array.entry_num;
437
438 iommufd_put_object(ucmd->ictx, &hwpt->obj);
439 out:
440 cmd->entry_num = done_num;
441 if (iommufd_ucmd_respond(ucmd, sizeof(*cmd)))
442 return -EFAULT;
443 return rc;
444 }
445