Merge branch 'misc.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[linux-2.6-microblaze.git] / arch / arm64 / kvm / vgic / vgic-mmio-v2.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * VGICv2 MMIO handling functions
4  */
5
6 #include <linux/irqchip/arm-gic.h>
7 #include <linux/kvm.h>
8 #include <linux/kvm_host.h>
9 #include <linux/nospec.h>
10
11 #include <kvm/iodev.h>
12 #include <kvm/arm_vgic.h>
13
14 #include "vgic.h"
15 #include "vgic-mmio.h"
16
17 /*
18  * The Revision field in the IIDR have the following meanings:
19  *
20  * Revision 1: Report GICv2 interrupts as group 0 instead of group 1
21  * Revision 2: Interrupt groups are guest-configurable and signaled using
22  *             their configured groups.
23  */
24
25 static unsigned long vgic_mmio_read_v2_misc(struct kvm_vcpu *vcpu,
26                                             gpa_t addr, unsigned int len)
27 {
28         struct vgic_dist *vgic = &vcpu->kvm->arch.vgic;
29         u32 value;
30
31         switch (addr & 0x0c) {
32         case GIC_DIST_CTRL:
33                 value = vgic->enabled ? GICD_ENABLE : 0;
34                 break;
35         case GIC_DIST_CTR:
36                 value = vgic->nr_spis + VGIC_NR_PRIVATE_IRQS;
37                 value = (value >> 5) - 1;
38                 value |= (atomic_read(&vcpu->kvm->online_vcpus) - 1) << 5;
39                 break;
40         case GIC_DIST_IIDR:
41                 value = (PRODUCT_ID_KVM << GICD_IIDR_PRODUCT_ID_SHIFT) |
42                         (vgic->implementation_rev << GICD_IIDR_REVISION_SHIFT) |
43                         (IMPLEMENTER_ARM << GICD_IIDR_IMPLEMENTER_SHIFT);
44                 break;
45         default:
46                 return 0;
47         }
48
49         return value;
50 }
51
52 static void vgic_mmio_write_v2_misc(struct kvm_vcpu *vcpu,
53                                     gpa_t addr, unsigned int len,
54                                     unsigned long val)
55 {
56         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
57         bool was_enabled = dist->enabled;
58
59         switch (addr & 0x0c) {
60         case GIC_DIST_CTRL:
61                 dist->enabled = val & GICD_ENABLE;
62                 if (!was_enabled && dist->enabled)
63                         vgic_kick_vcpus(vcpu->kvm);
64                 break;
65         case GIC_DIST_CTR:
66         case GIC_DIST_IIDR:
67                 /* Nothing to do */
68                 return;
69         }
70 }
71
72 static int vgic_mmio_uaccess_write_v2_misc(struct kvm_vcpu *vcpu,
73                                            gpa_t addr, unsigned int len,
74                                            unsigned long val)
75 {
76         switch (addr & 0x0c) {
77         case GIC_DIST_IIDR:
78                 if (val != vgic_mmio_read_v2_misc(vcpu, addr, len))
79                         return -EINVAL;
80
81                 /*
82                  * If we observe a write to GICD_IIDR we know that userspace
83                  * has been updated and has had a chance to cope with older
84                  * kernels (VGICv2 IIDR.Revision == 0) incorrectly reporting
85                  * interrupts as group 1, and therefore we now allow groups to
86                  * be user writable.  Doing this by default would break
87                  * migration from old kernels to new kernels with legacy
88                  * userspace.
89                  */
90                 vcpu->kvm->arch.vgic.v2_groups_user_writable = true;
91                 return 0;
92         }
93
94         vgic_mmio_write_v2_misc(vcpu, addr, len, val);
95         return 0;
96 }
97
98 static int vgic_mmio_uaccess_write_v2_group(struct kvm_vcpu *vcpu,
99                                             gpa_t addr, unsigned int len,
100                                             unsigned long val)
101 {
102         if (vcpu->kvm->arch.vgic.v2_groups_user_writable)
103                 vgic_mmio_write_group(vcpu, addr, len, val);
104
105         return 0;
106 }
107
108 static void vgic_mmio_write_sgir(struct kvm_vcpu *source_vcpu,
109                                  gpa_t addr, unsigned int len,
110                                  unsigned long val)
111 {
112         int nr_vcpus = atomic_read(&source_vcpu->kvm->online_vcpus);
113         int intid = val & 0xf;
114         int targets = (val >> 16) & 0xff;
115         int mode = (val >> 24) & 0x03;
116         int c;
117         struct kvm_vcpu *vcpu;
118         unsigned long flags;
119
120         switch (mode) {
121         case 0x0:               /* as specified by targets */
122                 break;
123         case 0x1:
124                 targets = (1U << nr_vcpus) - 1;                 /* all, ... */
125                 targets &= ~(1U << source_vcpu->vcpu_id);       /* but self */
126                 break;
127         case 0x2:               /* this very vCPU only */
128                 targets = (1U << source_vcpu->vcpu_id);
129                 break;
130         case 0x3:               /* reserved */
131                 return;
132         }
133
134         kvm_for_each_vcpu(c, vcpu, source_vcpu->kvm) {
135                 struct vgic_irq *irq;
136
137                 if (!(targets & (1U << c)))
138                         continue;
139
140                 irq = vgic_get_irq(source_vcpu->kvm, vcpu, intid);
141
142                 raw_spin_lock_irqsave(&irq->irq_lock, flags);
143                 irq->pending_latch = true;
144                 irq->source |= 1U << source_vcpu->vcpu_id;
145
146                 vgic_queue_irq_unlock(source_vcpu->kvm, irq, flags);
147                 vgic_put_irq(source_vcpu->kvm, irq);
148         }
149 }
150
151 static unsigned long vgic_mmio_read_target(struct kvm_vcpu *vcpu,
152                                            gpa_t addr, unsigned int len)
153 {
154         u32 intid = VGIC_ADDR_TO_INTID(addr, 8);
155         int i;
156         u64 val = 0;
157
158         for (i = 0; i < len; i++) {
159                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
160
161                 val |= (u64)irq->targets << (i * 8);
162
163                 vgic_put_irq(vcpu->kvm, irq);
164         }
165
166         return val;
167 }
168
169 static void vgic_mmio_write_target(struct kvm_vcpu *vcpu,
170                                    gpa_t addr, unsigned int len,
171                                    unsigned long val)
172 {
173         u32 intid = VGIC_ADDR_TO_INTID(addr, 8);
174         u8 cpu_mask = GENMASK(atomic_read(&vcpu->kvm->online_vcpus) - 1, 0);
175         int i;
176         unsigned long flags;
177
178         /* GICD_ITARGETSR[0-7] are read-only */
179         if (intid < VGIC_NR_PRIVATE_IRQS)
180                 return;
181
182         for (i = 0; i < len; i++) {
183                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, NULL, intid + i);
184                 int target;
185
186                 raw_spin_lock_irqsave(&irq->irq_lock, flags);
187
188                 irq->targets = (val >> (i * 8)) & cpu_mask;
189                 target = irq->targets ? __ffs(irq->targets) : 0;
190                 irq->target_vcpu = kvm_get_vcpu(vcpu->kvm, target);
191
192                 raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
193                 vgic_put_irq(vcpu->kvm, irq);
194         }
195 }
196
197 static unsigned long vgic_mmio_read_sgipend(struct kvm_vcpu *vcpu,
198                                             gpa_t addr, unsigned int len)
199 {
200         u32 intid = addr & 0x0f;
201         int i;
202         u64 val = 0;
203
204         for (i = 0; i < len; i++) {
205                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
206
207                 val |= (u64)irq->source << (i * 8);
208
209                 vgic_put_irq(vcpu->kvm, irq);
210         }
211         return val;
212 }
213
214 static void vgic_mmio_write_sgipendc(struct kvm_vcpu *vcpu,
215                                      gpa_t addr, unsigned int len,
216                                      unsigned long val)
217 {
218         u32 intid = addr & 0x0f;
219         int i;
220         unsigned long flags;
221
222         for (i = 0; i < len; i++) {
223                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
224
225                 raw_spin_lock_irqsave(&irq->irq_lock, flags);
226
227                 irq->source &= ~((val >> (i * 8)) & 0xff);
228                 if (!irq->source)
229                         irq->pending_latch = false;
230
231                 raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
232                 vgic_put_irq(vcpu->kvm, irq);
233         }
234 }
235
236 static void vgic_mmio_write_sgipends(struct kvm_vcpu *vcpu,
237                                      gpa_t addr, unsigned int len,
238                                      unsigned long val)
239 {
240         u32 intid = addr & 0x0f;
241         int i;
242         unsigned long flags;
243
244         for (i = 0; i < len; i++) {
245                 struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
246
247                 raw_spin_lock_irqsave(&irq->irq_lock, flags);
248
249                 irq->source |= (val >> (i * 8)) & 0xff;
250
251                 if (irq->source) {
252                         irq->pending_latch = true;
253                         vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
254                 } else {
255                         raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
256                 }
257                 vgic_put_irq(vcpu->kvm, irq);
258         }
259 }
260
261 #define GICC_ARCH_VERSION_V2    0x2
262
263 /* These are for userland accesses only, there is no guest-facing emulation. */
264 static unsigned long vgic_mmio_read_vcpuif(struct kvm_vcpu *vcpu,
265                                            gpa_t addr, unsigned int len)
266 {
267         struct vgic_vmcr vmcr;
268         u32 val;
269
270         vgic_get_vmcr(vcpu, &vmcr);
271
272         switch (addr & 0xff) {
273         case GIC_CPU_CTRL:
274                 val = vmcr.grpen0 << GIC_CPU_CTRL_EnableGrp0_SHIFT;
275                 val |= vmcr.grpen1 << GIC_CPU_CTRL_EnableGrp1_SHIFT;
276                 val |= vmcr.ackctl << GIC_CPU_CTRL_AckCtl_SHIFT;
277                 val |= vmcr.fiqen << GIC_CPU_CTRL_FIQEn_SHIFT;
278                 val |= vmcr.cbpr << GIC_CPU_CTRL_CBPR_SHIFT;
279                 val |= vmcr.eoim << GIC_CPU_CTRL_EOImodeNS_SHIFT;
280
281                 break;
282         case GIC_CPU_PRIMASK:
283                 /*
284                  * Our KVM_DEV_TYPE_ARM_VGIC_V2 device ABI exports the
285                  * PMR field as GICH_VMCR.VMPriMask rather than
286                  * GICC_PMR.Priority, so we expose the upper five bits of
287                  * priority mask to userspace using the lower bits in the
288                  * unsigned long.
289                  */
290                 val = (vmcr.pmr & GICV_PMR_PRIORITY_MASK) >>
291                         GICV_PMR_PRIORITY_SHIFT;
292                 break;
293         case GIC_CPU_BINPOINT:
294                 val = vmcr.bpr;
295                 break;
296         case GIC_CPU_ALIAS_BINPOINT:
297                 val = vmcr.abpr;
298                 break;
299         case GIC_CPU_IDENT:
300                 val = ((PRODUCT_ID_KVM << 20) |
301                        (GICC_ARCH_VERSION_V2 << 16) |
302                        IMPLEMENTER_ARM);
303                 break;
304         default:
305                 return 0;
306         }
307
308         return val;
309 }
310
311 static void vgic_mmio_write_vcpuif(struct kvm_vcpu *vcpu,
312                                    gpa_t addr, unsigned int len,
313                                    unsigned long val)
314 {
315         struct vgic_vmcr vmcr;
316
317         vgic_get_vmcr(vcpu, &vmcr);
318
319         switch (addr & 0xff) {
320         case GIC_CPU_CTRL:
321                 vmcr.grpen0 = !!(val & GIC_CPU_CTRL_EnableGrp0);
322                 vmcr.grpen1 = !!(val & GIC_CPU_CTRL_EnableGrp1);
323                 vmcr.ackctl = !!(val & GIC_CPU_CTRL_AckCtl);
324                 vmcr.fiqen = !!(val & GIC_CPU_CTRL_FIQEn);
325                 vmcr.cbpr = !!(val & GIC_CPU_CTRL_CBPR);
326                 vmcr.eoim = !!(val & GIC_CPU_CTRL_EOImodeNS);
327
328                 break;
329         case GIC_CPU_PRIMASK:
330                 /*
331                  * Our KVM_DEV_TYPE_ARM_VGIC_V2 device ABI exports the
332                  * PMR field as GICH_VMCR.VMPriMask rather than
333                  * GICC_PMR.Priority, so we expose the upper five bits of
334                  * priority mask to userspace using the lower bits in the
335                  * unsigned long.
336                  */
337                 vmcr.pmr = (val << GICV_PMR_PRIORITY_SHIFT) &
338                         GICV_PMR_PRIORITY_MASK;
339                 break;
340         case GIC_CPU_BINPOINT:
341                 vmcr.bpr = val;
342                 break;
343         case GIC_CPU_ALIAS_BINPOINT:
344                 vmcr.abpr = val;
345                 break;
346         }
347
348         vgic_set_vmcr(vcpu, &vmcr);
349 }
350
351 static unsigned long vgic_mmio_read_apr(struct kvm_vcpu *vcpu,
352                                         gpa_t addr, unsigned int len)
353 {
354         int n; /* which APRn is this */
355
356         n = (addr >> 2) & 0x3;
357
358         if (kvm_vgic_global_state.type == VGIC_V2) {
359                 /* GICv2 hardware systems support max. 32 groups */
360                 if (n != 0)
361                         return 0;
362                 return vcpu->arch.vgic_cpu.vgic_v2.vgic_apr;
363         } else {
364                 struct vgic_v3_cpu_if *vgicv3 = &vcpu->arch.vgic_cpu.vgic_v3;
365
366                 if (n > vgic_v3_max_apr_idx(vcpu))
367                         return 0;
368
369                 n = array_index_nospec(n, 4);
370
371                 /* GICv3 only uses ICH_AP1Rn for memory mapped (GICv2) guests */
372                 return vgicv3->vgic_ap1r[n];
373         }
374 }
375
376 static void vgic_mmio_write_apr(struct kvm_vcpu *vcpu,
377                                 gpa_t addr, unsigned int len,
378                                 unsigned long val)
379 {
380         int n; /* which APRn is this */
381
382         n = (addr >> 2) & 0x3;
383
384         if (kvm_vgic_global_state.type == VGIC_V2) {
385                 /* GICv2 hardware systems support max. 32 groups */
386                 if (n != 0)
387                         return;
388                 vcpu->arch.vgic_cpu.vgic_v2.vgic_apr = val;
389         } else {
390                 struct vgic_v3_cpu_if *vgicv3 = &vcpu->arch.vgic_cpu.vgic_v3;
391
392                 if (n > vgic_v3_max_apr_idx(vcpu))
393                         return;
394
395                 n = array_index_nospec(n, 4);
396
397                 /* GICv3 only uses ICH_AP1Rn for memory mapped (GICv2) guests */
398                 vgicv3->vgic_ap1r[n] = val;
399         }
400 }
401
402 static const struct vgic_register_region vgic_v2_dist_registers[] = {
403         REGISTER_DESC_WITH_LENGTH_UACCESS(GIC_DIST_CTRL,
404                 vgic_mmio_read_v2_misc, vgic_mmio_write_v2_misc,
405                 NULL, vgic_mmio_uaccess_write_v2_misc,
406                 12, VGIC_ACCESS_32bit),
407         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_IGROUP,
408                 vgic_mmio_read_group, vgic_mmio_write_group,
409                 NULL, vgic_mmio_uaccess_write_v2_group, 1,
410                 VGIC_ACCESS_32bit),
411         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_SET,
412                 vgic_mmio_read_enable, vgic_mmio_write_senable,
413                 NULL, vgic_uaccess_write_senable, 1,
414                 VGIC_ACCESS_32bit),
415         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ENABLE_CLEAR,
416                 vgic_mmio_read_enable, vgic_mmio_write_cenable,
417                 NULL, vgic_uaccess_write_cenable, 1,
418                 VGIC_ACCESS_32bit),
419         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_SET,
420                 vgic_mmio_read_pending, vgic_mmio_write_spending,
421                 NULL, vgic_uaccess_write_spending, 1,
422                 VGIC_ACCESS_32bit),
423         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PENDING_CLEAR,
424                 vgic_mmio_read_pending, vgic_mmio_write_cpending,
425                 NULL, vgic_uaccess_write_cpending, 1,
426                 VGIC_ACCESS_32bit),
427         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_SET,
428                 vgic_mmio_read_active, vgic_mmio_write_sactive,
429                 vgic_uaccess_read_active, vgic_mmio_uaccess_write_sactive, 1,
430                 VGIC_ACCESS_32bit),
431         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_ACTIVE_CLEAR,
432                 vgic_mmio_read_active, vgic_mmio_write_cactive,
433                 vgic_uaccess_read_active, vgic_mmio_uaccess_write_cactive, 1,
434                 VGIC_ACCESS_32bit),
435         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_PRI,
436                 vgic_mmio_read_priority, vgic_mmio_write_priority, NULL, NULL,
437                 8, VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
438         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_TARGET,
439                 vgic_mmio_read_target, vgic_mmio_write_target, NULL, NULL, 8,
440                 VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
441         REGISTER_DESC_WITH_BITS_PER_IRQ(GIC_DIST_CONFIG,
442                 vgic_mmio_read_config, vgic_mmio_write_config, NULL, NULL, 2,
443                 VGIC_ACCESS_32bit),
444         REGISTER_DESC_WITH_LENGTH(GIC_DIST_SOFTINT,
445                 vgic_mmio_read_raz, vgic_mmio_write_sgir, 4,
446                 VGIC_ACCESS_32bit),
447         REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_CLEAR,
448                 vgic_mmio_read_sgipend, vgic_mmio_write_sgipendc, 16,
449                 VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
450         REGISTER_DESC_WITH_LENGTH(GIC_DIST_SGI_PENDING_SET,
451                 vgic_mmio_read_sgipend, vgic_mmio_write_sgipends, 16,
452                 VGIC_ACCESS_32bit | VGIC_ACCESS_8bit),
453 };
454
455 static const struct vgic_register_region vgic_v2_cpu_registers[] = {
456         REGISTER_DESC_WITH_LENGTH(GIC_CPU_CTRL,
457                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
458                 VGIC_ACCESS_32bit),
459         REGISTER_DESC_WITH_LENGTH(GIC_CPU_PRIMASK,
460                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
461                 VGIC_ACCESS_32bit),
462         REGISTER_DESC_WITH_LENGTH(GIC_CPU_BINPOINT,
463                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
464                 VGIC_ACCESS_32bit),
465         REGISTER_DESC_WITH_LENGTH(GIC_CPU_ALIAS_BINPOINT,
466                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
467                 VGIC_ACCESS_32bit),
468         REGISTER_DESC_WITH_LENGTH(GIC_CPU_ACTIVEPRIO,
469                 vgic_mmio_read_apr, vgic_mmio_write_apr, 16,
470                 VGIC_ACCESS_32bit),
471         REGISTER_DESC_WITH_LENGTH(GIC_CPU_IDENT,
472                 vgic_mmio_read_vcpuif, vgic_mmio_write_vcpuif, 4,
473                 VGIC_ACCESS_32bit),
474 };
475
476 unsigned int vgic_v2_init_dist_iodev(struct vgic_io_device *dev)
477 {
478         dev->regions = vgic_v2_dist_registers;
479         dev->nr_regions = ARRAY_SIZE(vgic_v2_dist_registers);
480
481         kvm_iodevice_init(&dev->dev, &kvm_io_gic_ops);
482
483         return SZ_4K;
484 }
485
486 int vgic_v2_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
487 {
488         const struct vgic_register_region *region;
489         struct vgic_io_device iodev;
490         struct vgic_reg_attr reg_attr;
491         struct kvm_vcpu *vcpu;
492         gpa_t addr;
493         int ret;
494
495         ret = vgic_v2_parse_attr(dev, attr, &reg_attr);
496         if (ret)
497                 return ret;
498
499         vcpu = reg_attr.vcpu;
500         addr = reg_attr.addr;
501
502         switch (attr->group) {
503         case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
504                 iodev.regions = vgic_v2_dist_registers;
505                 iodev.nr_regions = ARRAY_SIZE(vgic_v2_dist_registers);
506                 iodev.base_addr = 0;
507                 break;
508         case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
509                 iodev.regions = vgic_v2_cpu_registers;
510                 iodev.nr_regions = ARRAY_SIZE(vgic_v2_cpu_registers);
511                 iodev.base_addr = 0;
512                 break;
513         default:
514                 return -ENXIO;
515         }
516
517         /* We only support aligned 32-bit accesses. */
518         if (addr & 3)
519                 return -ENXIO;
520
521         region = vgic_get_mmio_region(vcpu, &iodev, addr, sizeof(u32));
522         if (!region)
523                 return -ENXIO;
524
525         return 0;
526 }
527
528 int vgic_v2_cpuif_uaccess(struct kvm_vcpu *vcpu, bool is_write,
529                           int offset, u32 *val)
530 {
531         struct vgic_io_device dev = {
532                 .regions = vgic_v2_cpu_registers,
533                 .nr_regions = ARRAY_SIZE(vgic_v2_cpu_registers),
534                 .iodev_type = IODEV_CPUIF,
535         };
536
537         return vgic_uaccess(vcpu, &dev, is_write, offset, val);
538 }
539
540 int vgic_v2_dist_uaccess(struct kvm_vcpu *vcpu, bool is_write,
541                          int offset, u32 *val)
542 {
543         struct vgic_io_device dev = {
544                 .regions = vgic_v2_dist_registers,
545                 .nr_regions = ARRAY_SIZE(vgic_v2_dist_registers),
546                 .iodev_type = IODEV_DIST,
547         };
548
549         return vgic_uaccess(vcpu, &dev, is_write, offset, val);
550 }