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9#include <linux/pci.h>
10#include <linux/iommu.h>
11#include <linux/iommu-helper.h>
12#include <linux/sizes.h>
13#include <asm/pci_dma.h>
14
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19
20#define S390_IOMMU_PGSIZES (~0xFFFUL)
21
22static const struct iommu_ops s390_iommu_ops;
23
24struct s390_domain {
25 struct iommu_domain domain;
26 struct list_head devices;
27 unsigned long *dma_table;
28 spinlock_t dma_table_lock;
29 spinlock_t list_lock;
30};
31
32struct s390_domain_device {
33 struct list_head list;
34 struct zpci_dev *zdev;
35};
36
37static struct s390_domain *to_s390_domain(struct iommu_domain *dom)
38{
39 return container_of(dom, struct s390_domain, domain);
40}
41
42static bool s390_iommu_capable(enum iommu_cap cap)
43{
44 switch (cap) {
45 case IOMMU_CAP_CACHE_COHERENCY:
46 return true;
47 case IOMMU_CAP_INTR_REMAP:
48 return true;
49 default:
50 return false;
51 }
52}
53
54static struct iommu_domain *s390_domain_alloc(unsigned domain_type)
55{
56 struct s390_domain *s390_domain;
57
58 if (domain_type != IOMMU_DOMAIN_UNMANAGED)
59 return NULL;
60
61 s390_domain = kzalloc(sizeof(*s390_domain), GFP_KERNEL);
62 if (!s390_domain)
63 return NULL;
64
65 s390_domain->dma_table = dma_alloc_cpu_table();
66 if (!s390_domain->dma_table) {
67 kfree(s390_domain);
68 return NULL;
69 }
70
71 spin_lock_init(&s390_domain->dma_table_lock);
72 spin_lock_init(&s390_domain->list_lock);
73 INIT_LIST_HEAD(&s390_domain->devices);
74
75 return &s390_domain->domain;
76}
77
78static void s390_domain_free(struct iommu_domain *domain)
79{
80 struct s390_domain *s390_domain = to_s390_domain(domain);
81
82 dma_cleanup_tables(s390_domain->dma_table);
83 kfree(s390_domain);
84}
85
86static int s390_iommu_attach_device(struct iommu_domain *domain,
87 struct device *dev)
88{
89 struct s390_domain *s390_domain = to_s390_domain(domain);
90 struct zpci_dev *zdev = to_zpci_dev(dev);
91 struct s390_domain_device *domain_device;
92 unsigned long flags;
93 int rc;
94
95 if (!zdev)
96 return -ENODEV;
97
98 domain_device = kzalloc(sizeof(*domain_device), GFP_KERNEL);
99 if (!domain_device)
100 return -ENOMEM;
101
102 if (zdev->dma_table)
103 zpci_dma_exit_device(zdev);
104
105 zdev->dma_table = s390_domain->dma_table;
106 rc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
107 (u64) zdev->dma_table);
108 if (rc)
109 goto out_restore;
110
111 spin_lock_irqsave(&s390_domain->list_lock, flags);
112
113 if (list_empty(&s390_domain->devices)) {
114 domain->geometry.aperture_start = zdev->start_dma;
115 domain->geometry.aperture_end = zdev->end_dma;
116 domain->geometry.force_aperture = true;
117
118 } else if (domain->geometry.aperture_start != zdev->start_dma ||
119 domain->geometry.aperture_end != zdev->end_dma) {
120 rc = -EINVAL;
121 spin_unlock_irqrestore(&s390_domain->list_lock, flags);
122 goto out_restore;
123 }
124 domain_device->zdev = zdev;
125 zdev->s390_domain = s390_domain;
126 list_add(&domain_device->list, &s390_domain->devices);
127 spin_unlock_irqrestore(&s390_domain->list_lock, flags);
128
129 return 0;
130
131out_restore:
132 zpci_dma_init_device(zdev);
133 kfree(domain_device);
134
135 return rc;
136}
137
138static void s390_iommu_detach_device(struct iommu_domain *domain,
139 struct device *dev)
140{
141 struct s390_domain *s390_domain = to_s390_domain(domain);
142 struct zpci_dev *zdev = to_zpci_dev(dev);
143 struct s390_domain_device *domain_device, *tmp;
144 unsigned long flags;
145 int found = 0;
146
147 if (!zdev)
148 return;
149
150 spin_lock_irqsave(&s390_domain->list_lock, flags);
151 list_for_each_entry_safe(domain_device, tmp, &s390_domain->devices,
152 list) {
153 if (domain_device->zdev == zdev) {
154 list_del(&domain_device->list);
155 kfree(domain_device);
156 found = 1;
157 break;
158 }
159 }
160 spin_unlock_irqrestore(&s390_domain->list_lock, flags);
161
162 if (found) {
163 zdev->s390_domain = NULL;
164 zpci_unregister_ioat(zdev, 0);
165 zpci_dma_init_device(zdev);
166 }
167}
168
169static struct iommu_device *s390_iommu_probe_device(struct device *dev)
170{
171 struct zpci_dev *zdev = to_zpci_dev(dev);
172
173 return &zdev->iommu_dev;
174}
175
176static void s390_iommu_release_device(struct device *dev)
177{
178 struct zpci_dev *zdev = to_zpci_dev(dev);
179 struct iommu_domain *domain;
180
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190
191
192 if (zdev && zdev->s390_domain) {
193 domain = iommu_get_domain_for_dev(dev);
194 if (domain)
195 s390_iommu_detach_device(domain, dev);
196 }
197}
198
199static int s390_iommu_update_trans(struct s390_domain *s390_domain,
200 unsigned long pa, dma_addr_t dma_addr,
201 size_t size, int flags)
202{
203 struct s390_domain_device *domain_device;
204 u8 *page_addr = (u8 *) (pa & PAGE_MASK);
205 dma_addr_t start_dma_addr = dma_addr;
206 unsigned long irq_flags, nr_pages, i;
207 unsigned long *entry;
208 int rc = 0;
209
210 if (dma_addr < s390_domain->domain.geometry.aperture_start ||
211 dma_addr + size > s390_domain->domain.geometry.aperture_end)
212 return -EINVAL;
213
214 nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
215 if (!nr_pages)
216 return 0;
217
218 spin_lock_irqsave(&s390_domain->dma_table_lock, irq_flags);
219 for (i = 0; i < nr_pages; i++) {
220 entry = dma_walk_cpu_trans(s390_domain->dma_table, dma_addr);
221 if (!entry) {
222 rc = -ENOMEM;
223 goto undo_cpu_trans;
224 }
225 dma_update_cpu_trans(entry, page_addr, flags);
226 page_addr += PAGE_SIZE;
227 dma_addr += PAGE_SIZE;
228 }
229
230 spin_lock(&s390_domain->list_lock);
231 list_for_each_entry(domain_device, &s390_domain->devices, list) {
232 rc = zpci_refresh_trans((u64) domain_device->zdev->fh << 32,
233 start_dma_addr, nr_pages * PAGE_SIZE);
234 if (rc)
235 break;
236 }
237 spin_unlock(&s390_domain->list_lock);
238
239undo_cpu_trans:
240 if (rc && ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID)) {
241 flags = ZPCI_PTE_INVALID;
242 while (i-- > 0) {
243 page_addr -= PAGE_SIZE;
244 dma_addr -= PAGE_SIZE;
245 entry = dma_walk_cpu_trans(s390_domain->dma_table,
246 dma_addr);
247 if (!entry)
248 break;
249 dma_update_cpu_trans(entry, page_addr, flags);
250 }
251 }
252 spin_unlock_irqrestore(&s390_domain->dma_table_lock, irq_flags);
253
254 return rc;
255}
256
257static int s390_iommu_map(struct iommu_domain *domain, unsigned long iova,
258 phys_addr_t paddr, size_t size, int prot, gfp_t gfp)
259{
260 struct s390_domain *s390_domain = to_s390_domain(domain);
261 int flags = ZPCI_PTE_VALID, rc = 0;
262
263 if (!(prot & IOMMU_READ))
264 return -EINVAL;
265
266 if (!(prot & IOMMU_WRITE))
267 flags |= ZPCI_TABLE_PROTECTED;
268
269 rc = s390_iommu_update_trans(s390_domain, (unsigned long) paddr, iova,
270 size, flags);
271
272 return rc;
273}
274
275static phys_addr_t s390_iommu_iova_to_phys(struct iommu_domain *domain,
276 dma_addr_t iova)
277{
278 struct s390_domain *s390_domain = to_s390_domain(domain);
279 unsigned long *sto, *pto, *rto, flags;
280 unsigned int rtx, sx, px;
281 phys_addr_t phys = 0;
282
283 if (iova < domain->geometry.aperture_start ||
284 iova > domain->geometry.aperture_end)
285 return 0;
286
287 rtx = calc_rtx(iova);
288 sx = calc_sx(iova);
289 px = calc_px(iova);
290 rto = s390_domain->dma_table;
291
292 spin_lock_irqsave(&s390_domain->dma_table_lock, flags);
293 if (rto && reg_entry_isvalid(rto[rtx])) {
294 sto = get_rt_sto(rto[rtx]);
295 if (sto && reg_entry_isvalid(sto[sx])) {
296 pto = get_st_pto(sto[sx]);
297 if (pto && pt_entry_isvalid(pto[px]))
298 phys = pto[px] & ZPCI_PTE_ADDR_MASK;
299 }
300 }
301 spin_unlock_irqrestore(&s390_domain->dma_table_lock, flags);
302
303 return phys;
304}
305
306static size_t s390_iommu_unmap(struct iommu_domain *domain,
307 unsigned long iova, size_t size,
308 struct iommu_iotlb_gather *gather)
309{
310 struct s390_domain *s390_domain = to_s390_domain(domain);
311 int flags = ZPCI_PTE_INVALID;
312 phys_addr_t paddr;
313 int rc;
314
315 paddr = s390_iommu_iova_to_phys(domain, iova);
316 if (!paddr)
317 return 0;
318
319 rc = s390_iommu_update_trans(s390_domain, (unsigned long) paddr, iova,
320 size, flags);
321 if (rc)
322 return 0;
323
324 return size;
325}
326
327int zpci_init_iommu(struct zpci_dev *zdev)
328{
329 int rc = 0;
330
331 rc = iommu_device_sysfs_add(&zdev->iommu_dev, NULL, NULL,
332 "s390-iommu.%08x", zdev->fid);
333 if (rc)
334 goto out_err;
335
336 iommu_device_set_ops(&zdev->iommu_dev, &s390_iommu_ops);
337
338 rc = iommu_device_register(&zdev->iommu_dev);
339 if (rc)
340 goto out_sysfs;
341
342 return 0;
343
344out_sysfs:
345 iommu_device_sysfs_remove(&zdev->iommu_dev);
346
347out_err:
348 return rc;
349}
350
351void zpci_destroy_iommu(struct zpci_dev *zdev)
352{
353 iommu_device_unregister(&zdev->iommu_dev);
354 iommu_device_sysfs_remove(&zdev->iommu_dev);
355}
356
357static const struct iommu_ops s390_iommu_ops = {
358 .capable = s390_iommu_capable,
359 .domain_alloc = s390_domain_alloc,
360 .domain_free = s390_domain_free,
361 .attach_dev = s390_iommu_attach_device,
362 .detach_dev = s390_iommu_detach_device,
363 .map = s390_iommu_map,
364 .unmap = s390_iommu_unmap,
365 .iova_to_phys = s390_iommu_iova_to_phys,
366 .probe_device = s390_iommu_probe_device,
367 .release_device = s390_iommu_release_device,
368 .device_group = generic_device_group,
369 .pgsize_bitmap = S390_IOMMU_PGSIZES,
370};
371
372static int __init s390_iommu_init(void)
373{
374 return bus_set_iommu(&pci_bus_type, &s390_iommu_ops);
375}
376subsys_initcall(s390_iommu_init);
377
