a24fdacf5381fffb26f0a246b885d31a160661f4
[firefly-linux-kernel-4.4.55.git] / virt / kvm / arm / vgic.c
1 /*
2  * Copyright (C) 2012 ARM Ltd.
3  * Author: Marc Zyngier <marc.zyngier@arm.com>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17  */
18
19 #include <linux/cpu.h>
20 #include <linux/kvm.h>
21 #include <linux/kvm_host.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/of.h>
25 #include <linux/of_address.h>
26 #include <linux/of_irq.h>
27 #include <linux/uaccess.h>
28
29 #include <linux/irqchip/arm-gic.h>
30
31 #include <asm/kvm_emulate.h>
32 #include <asm/kvm_arm.h>
33 #include <asm/kvm_mmu.h>
34
35 /*
36  * How the whole thing works (courtesy of Christoffer Dall):
37  *
38  * - At any time, the dist->irq_pending_on_cpu is the oracle that knows if
39  *   something is pending on the CPU interface.
40  * - Interrupts that are pending on the distributor are stored on the
41  *   vgic.irq_pending vgic bitmap (this bitmap is updated by both user land
42  *   ioctls and guest mmio ops, and other in-kernel peripherals such as the
43  *   arch. timers).
44  * - Every time the bitmap changes, the irq_pending_on_cpu oracle is
45  *   recalculated
46  * - To calculate the oracle, we need info for each cpu from
47  *   compute_pending_for_cpu, which considers:
48  *   - PPI: dist->irq_pending & dist->irq_enable
49  *   - SPI: dist->irq_pending & dist->irq_enable & dist->irq_spi_target
50  *   - irq_spi_target is a 'formatted' version of the GICD_ITARGETSRn
51  *     registers, stored on each vcpu. We only keep one bit of
52  *     information per interrupt, making sure that only one vcpu can
53  *     accept the interrupt.
54  * - If any of the above state changes, we must recalculate the oracle.
55  * - The same is true when injecting an interrupt, except that we only
56  *   consider a single interrupt at a time. The irq_spi_cpu array
57  *   contains the target CPU for each SPI.
58  *
59  * The handling of level interrupts adds some extra complexity. We
60  * need to track when the interrupt has been EOIed, so we can sample
61  * the 'line' again. This is achieved as such:
62  *
63  * - When a level interrupt is moved onto a vcpu, the corresponding
64  *   bit in irq_queued is set. As long as this bit is set, the line
65  *   will be ignored for further interrupts. The interrupt is injected
66  *   into the vcpu with the GICH_LR_EOI bit set (generate a
67  *   maintenance interrupt on EOI).
68  * - When the interrupt is EOIed, the maintenance interrupt fires,
69  *   and clears the corresponding bit in irq_queued. This allows the
70  *   interrupt line to be sampled again.
71  * - Note that level-triggered interrupts can also be set to pending from
72  *   writes to GICD_ISPENDRn and lowering the external input line does not
73  *   cause the interrupt to become inactive in such a situation.
74  *   Conversely, writes to GICD_ICPENDRn do not cause the interrupt to become
75  *   inactive as long as the external input line is held high.
76  */
77
78 #define VGIC_ADDR_UNDEF         (-1)
79 #define IS_VGIC_ADDR_UNDEF(_x)  ((_x) == VGIC_ADDR_UNDEF)
80
81 #define PRODUCT_ID_KVM          0x4b    /* ASCII code K */
82 #define IMPLEMENTER_ARM         0x43b
83 #define GICC_ARCH_VERSION_V2    0x2
84
85 #define ACCESS_READ_VALUE       (1 << 0)
86 #define ACCESS_READ_RAZ         (0 << 0)
87 #define ACCESS_READ_MASK(x)     ((x) & (1 << 0))
88 #define ACCESS_WRITE_IGNORED    (0 << 1)
89 #define ACCESS_WRITE_SETBIT     (1 << 1)
90 #define ACCESS_WRITE_CLEARBIT   (2 << 1)
91 #define ACCESS_WRITE_VALUE      (3 << 1)
92 #define ACCESS_WRITE_MASK(x)    ((x) & (3 << 1))
93
94 static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu);
95 static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu);
96 static void vgic_update_state(struct kvm *kvm);
97 static void vgic_kick_vcpus(struct kvm *kvm);
98 static u8 *vgic_get_sgi_sources(struct vgic_dist *dist, int vcpu_id, int sgi);
99 static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg);
100 static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr);
101 static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr, struct vgic_lr lr_desc);
102 static void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
103 static void vgic_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr);
104
105 static const struct vgic_ops *vgic_ops;
106 static const struct vgic_params *vgic;
107
108 /*
109  * struct vgic_bitmap contains a bitmap made of unsigned longs, but
110  * extracts u32s out of them.
111  *
112  * This does not work on 64-bit BE systems, because the bitmap access
113  * will store two consecutive 32-bit words with the higher-addressed
114  * register's bits at the lower index and the lower-addressed register's
115  * bits at the higher index.
116  *
117  * Therefore, swizzle the register index when accessing the 32-bit word
118  * registers to access the right register's value.
119  */
120 #if defined(CONFIG_CPU_BIG_ENDIAN) && BITS_PER_LONG == 64
121 #define REG_OFFSET_SWIZZLE      1
122 #else
123 #define REG_OFFSET_SWIZZLE      0
124 #endif
125
126 static int vgic_init_bitmap(struct vgic_bitmap *b, int nr_cpus, int nr_irqs)
127 {
128         int nr_longs;
129
130         nr_longs = nr_cpus + BITS_TO_LONGS(nr_irqs - VGIC_NR_PRIVATE_IRQS);
131
132         b->private = kzalloc(sizeof(unsigned long) * nr_longs, GFP_KERNEL);
133         if (!b->private)
134                 return -ENOMEM;
135
136         b->shared = b->private + nr_cpus;
137
138         return 0;
139 }
140
141 static void vgic_free_bitmap(struct vgic_bitmap *b)
142 {
143         kfree(b->private);
144         b->private = NULL;
145         b->shared = NULL;
146 }
147
148 static u32 *vgic_bitmap_get_reg(struct vgic_bitmap *x,
149                                 int cpuid, u32 offset)
150 {
151         offset >>= 2;
152         if (!offset)
153                 return (u32 *)(x->private + cpuid) + REG_OFFSET_SWIZZLE;
154         else
155                 return (u32 *)(x->shared) + ((offset - 1) ^ REG_OFFSET_SWIZZLE);
156 }
157
158 static int vgic_bitmap_get_irq_val(struct vgic_bitmap *x,
159                                    int cpuid, int irq)
160 {
161         if (irq < VGIC_NR_PRIVATE_IRQS)
162                 return test_bit(irq, x->private + cpuid);
163
164         return test_bit(irq - VGIC_NR_PRIVATE_IRQS, x->shared);
165 }
166
167 static void vgic_bitmap_set_irq_val(struct vgic_bitmap *x, int cpuid,
168                                     int irq, int val)
169 {
170         unsigned long *reg;
171
172         if (irq < VGIC_NR_PRIVATE_IRQS) {
173                 reg = x->private + cpuid;
174         } else {
175                 reg = x->shared;
176                 irq -= VGIC_NR_PRIVATE_IRQS;
177         }
178
179         if (val)
180                 set_bit(irq, reg);
181         else
182                 clear_bit(irq, reg);
183 }
184
185 static unsigned long *vgic_bitmap_get_cpu_map(struct vgic_bitmap *x, int cpuid)
186 {
187         return x->private + cpuid;
188 }
189
190 static unsigned long *vgic_bitmap_get_shared_map(struct vgic_bitmap *x)
191 {
192         return x->shared;
193 }
194
195 static int vgic_init_bytemap(struct vgic_bytemap *x, int nr_cpus, int nr_irqs)
196 {
197         int size;
198
199         size  = nr_cpus * VGIC_NR_PRIVATE_IRQS;
200         size += nr_irqs - VGIC_NR_PRIVATE_IRQS;
201
202         x->private = kzalloc(size, GFP_KERNEL);
203         if (!x->private)
204                 return -ENOMEM;
205
206         x->shared = x->private + nr_cpus * VGIC_NR_PRIVATE_IRQS / sizeof(u32);
207         return 0;
208 }
209
210 static void vgic_free_bytemap(struct vgic_bytemap *b)
211 {
212         kfree(b->private);
213         b->private = NULL;
214         b->shared = NULL;
215 }
216
217 static u32 *vgic_bytemap_get_reg(struct vgic_bytemap *x, int cpuid, u32 offset)
218 {
219         u32 *reg;
220
221         if (offset < VGIC_NR_PRIVATE_IRQS) {
222                 reg = x->private;
223                 offset += cpuid * VGIC_NR_PRIVATE_IRQS;
224         } else {
225                 reg = x->shared;
226                 offset -= VGIC_NR_PRIVATE_IRQS;
227         }
228
229         return reg + (offset / sizeof(u32));
230 }
231
232 #define VGIC_CFG_LEVEL  0
233 #define VGIC_CFG_EDGE   1
234
235 static bool vgic_irq_is_edge(struct kvm_vcpu *vcpu, int irq)
236 {
237         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
238         int irq_val;
239
240         irq_val = vgic_bitmap_get_irq_val(&dist->irq_cfg, vcpu->vcpu_id, irq);
241         return irq_val == VGIC_CFG_EDGE;
242 }
243
244 static int vgic_irq_is_enabled(struct kvm_vcpu *vcpu, int irq)
245 {
246         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
247
248         return vgic_bitmap_get_irq_val(&dist->irq_enabled, vcpu->vcpu_id, irq);
249 }
250
251 static int vgic_irq_is_queued(struct kvm_vcpu *vcpu, int irq)
252 {
253         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
254
255         return vgic_bitmap_get_irq_val(&dist->irq_queued, vcpu->vcpu_id, irq);
256 }
257
258 static void vgic_irq_set_queued(struct kvm_vcpu *vcpu, int irq)
259 {
260         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
261
262         vgic_bitmap_set_irq_val(&dist->irq_queued, vcpu->vcpu_id, irq, 1);
263 }
264
265 static void vgic_irq_clear_queued(struct kvm_vcpu *vcpu, int irq)
266 {
267         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
268
269         vgic_bitmap_set_irq_val(&dist->irq_queued, vcpu->vcpu_id, irq, 0);
270 }
271
272 static int vgic_dist_irq_get_level(struct kvm_vcpu *vcpu, int irq)
273 {
274         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
275
276         return vgic_bitmap_get_irq_val(&dist->irq_level, vcpu->vcpu_id, irq);
277 }
278
279 static void vgic_dist_irq_set_level(struct kvm_vcpu *vcpu, int irq)
280 {
281         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
282
283         vgic_bitmap_set_irq_val(&dist->irq_level, vcpu->vcpu_id, irq, 1);
284 }
285
286 static void vgic_dist_irq_clear_level(struct kvm_vcpu *vcpu, int irq)
287 {
288         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
289
290         vgic_bitmap_set_irq_val(&dist->irq_level, vcpu->vcpu_id, irq, 0);
291 }
292
293 static int vgic_dist_irq_soft_pend(struct kvm_vcpu *vcpu, int irq)
294 {
295         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
296
297         return vgic_bitmap_get_irq_val(&dist->irq_soft_pend, vcpu->vcpu_id, irq);
298 }
299
300 static void vgic_dist_irq_clear_soft_pend(struct kvm_vcpu *vcpu, int irq)
301 {
302         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
303
304         vgic_bitmap_set_irq_val(&dist->irq_soft_pend, vcpu->vcpu_id, irq, 0);
305 }
306
307 static int vgic_dist_irq_is_pending(struct kvm_vcpu *vcpu, int irq)
308 {
309         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
310
311         return vgic_bitmap_get_irq_val(&dist->irq_pending, vcpu->vcpu_id, irq);
312 }
313
314 static void vgic_dist_irq_set_pending(struct kvm_vcpu *vcpu, int irq)
315 {
316         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
317
318         vgic_bitmap_set_irq_val(&dist->irq_pending, vcpu->vcpu_id, irq, 1);
319 }
320
321 static void vgic_dist_irq_clear_pending(struct kvm_vcpu *vcpu, int irq)
322 {
323         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
324
325         vgic_bitmap_set_irq_val(&dist->irq_pending, vcpu->vcpu_id, irq, 0);
326 }
327
328 static void vgic_cpu_irq_set(struct kvm_vcpu *vcpu, int irq)
329 {
330         if (irq < VGIC_NR_PRIVATE_IRQS)
331                 set_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
332         else
333                 set_bit(irq - VGIC_NR_PRIVATE_IRQS,
334                         vcpu->arch.vgic_cpu.pending_shared);
335 }
336
337 static void vgic_cpu_irq_clear(struct kvm_vcpu *vcpu, int irq)
338 {
339         if (irq < VGIC_NR_PRIVATE_IRQS)
340                 clear_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
341         else
342                 clear_bit(irq - VGIC_NR_PRIVATE_IRQS,
343                           vcpu->arch.vgic_cpu.pending_shared);
344 }
345
346 static bool vgic_can_sample_irq(struct kvm_vcpu *vcpu, int irq)
347 {
348         return vgic_irq_is_edge(vcpu, irq) || !vgic_irq_is_queued(vcpu, irq);
349 }
350
351 static u32 mmio_data_read(struct kvm_exit_mmio *mmio, u32 mask)
352 {
353         return le32_to_cpu(*((u32 *)mmio->data)) & mask;
354 }
355
356 static void mmio_data_write(struct kvm_exit_mmio *mmio, u32 mask, u32 value)
357 {
358         *((u32 *)mmio->data) = cpu_to_le32(value) & mask;
359 }
360
361 /**
362  * vgic_reg_access - access vgic register
363  * @mmio:   pointer to the data describing the mmio access
364  * @reg:    pointer to the virtual backing of vgic distributor data
365  * @offset: least significant 2 bits used for word offset
366  * @mode:   ACCESS_ mode (see defines above)
367  *
368  * Helper to make vgic register access easier using one of the access
369  * modes defined for vgic register access
370  * (read,raz,write-ignored,setbit,clearbit,write)
371  */
372 static void vgic_reg_access(struct kvm_exit_mmio *mmio, u32 *reg,
373                             phys_addr_t offset, int mode)
374 {
375         int word_offset = (offset & 3) * 8;
376         u32 mask = (1UL << (mmio->len * 8)) - 1;
377         u32 regval;
378
379         /*
380          * Any alignment fault should have been delivered to the guest
381          * directly (ARM ARM B3.12.7 "Prioritization of aborts").
382          */
383
384         if (reg) {
385                 regval = *reg;
386         } else {
387                 BUG_ON(mode != (ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED));
388                 regval = 0;
389         }
390
391         if (mmio->is_write) {
392                 u32 data = mmio_data_read(mmio, mask) << word_offset;
393                 switch (ACCESS_WRITE_MASK(mode)) {
394                 case ACCESS_WRITE_IGNORED:
395                         return;
396
397                 case ACCESS_WRITE_SETBIT:
398                         regval |= data;
399                         break;
400
401                 case ACCESS_WRITE_CLEARBIT:
402                         regval &= ~data;
403                         break;
404
405                 case ACCESS_WRITE_VALUE:
406                         regval = (regval & ~(mask << word_offset)) | data;
407                         break;
408                 }
409                 *reg = regval;
410         } else {
411                 switch (ACCESS_READ_MASK(mode)) {
412                 case ACCESS_READ_RAZ:
413                         regval = 0;
414                         /* fall through */
415
416                 case ACCESS_READ_VALUE:
417                         mmio_data_write(mmio, mask, regval >> word_offset);
418                 }
419         }
420 }
421
422 static bool handle_mmio_misc(struct kvm_vcpu *vcpu,
423                              struct kvm_exit_mmio *mmio, phys_addr_t offset)
424 {
425         u32 reg;
426         u32 word_offset = offset & 3;
427
428         switch (offset & ~3) {
429         case 0:                 /* GICD_CTLR */
430                 reg = vcpu->kvm->arch.vgic.enabled;
431                 vgic_reg_access(mmio, &reg, word_offset,
432                                 ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
433                 if (mmio->is_write) {
434                         vcpu->kvm->arch.vgic.enabled = reg & 1;
435                         vgic_update_state(vcpu->kvm);
436                         return true;
437                 }
438                 break;
439
440         case 4:                 /* GICD_TYPER */
441                 reg  = (atomic_read(&vcpu->kvm->online_vcpus) - 1) << 5;
442                 reg |= (VGIC_NR_IRQS >> 5) - 1;
443                 vgic_reg_access(mmio, &reg, word_offset,
444                                 ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
445                 break;
446
447         case 8:                 /* GICD_IIDR */
448                 reg = (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
449                 vgic_reg_access(mmio, &reg, word_offset,
450                                 ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
451                 break;
452         }
453
454         return false;
455 }
456
457 static bool handle_mmio_raz_wi(struct kvm_vcpu *vcpu,
458                                struct kvm_exit_mmio *mmio, phys_addr_t offset)
459 {
460         vgic_reg_access(mmio, NULL, offset,
461                         ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED);
462         return false;
463 }
464
465 static bool handle_mmio_set_enable_reg(struct kvm_vcpu *vcpu,
466                                        struct kvm_exit_mmio *mmio,
467                                        phys_addr_t offset)
468 {
469         u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_enabled,
470                                        vcpu->vcpu_id, offset);
471         vgic_reg_access(mmio, reg, offset,
472                         ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
473         if (mmio->is_write) {
474                 vgic_update_state(vcpu->kvm);
475                 return true;
476         }
477
478         return false;
479 }
480
481 static bool handle_mmio_clear_enable_reg(struct kvm_vcpu *vcpu,
482                                          struct kvm_exit_mmio *mmio,
483                                          phys_addr_t offset)
484 {
485         u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_enabled,
486                                        vcpu->vcpu_id, offset);
487         vgic_reg_access(mmio, reg, offset,
488                         ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
489         if (mmio->is_write) {
490                 if (offset < 4) /* Force SGI enabled */
491                         *reg |= 0xffff;
492                 vgic_retire_disabled_irqs(vcpu);
493                 vgic_update_state(vcpu->kvm);
494                 return true;
495         }
496
497         return false;
498 }
499
500 static bool handle_mmio_set_pending_reg(struct kvm_vcpu *vcpu,
501                                         struct kvm_exit_mmio *mmio,
502                                         phys_addr_t offset)
503 {
504         u32 *reg, orig;
505         u32 level_mask;
506         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
507
508         reg = vgic_bitmap_get_reg(&dist->irq_cfg, vcpu->vcpu_id, offset);
509         level_mask = (~(*reg));
510
511         /* Mark both level and edge triggered irqs as pending */
512         reg = vgic_bitmap_get_reg(&dist->irq_pending, vcpu->vcpu_id, offset);
513         orig = *reg;
514         vgic_reg_access(mmio, reg, offset,
515                         ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
516
517         if (mmio->is_write) {
518                 /* Set the soft-pending flag only for level-triggered irqs */
519                 reg = vgic_bitmap_get_reg(&dist->irq_soft_pend,
520                                           vcpu->vcpu_id, offset);
521                 vgic_reg_access(mmio, reg, offset,
522                                 ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
523                 *reg &= level_mask;
524
525                 /* Ignore writes to SGIs */
526                 if (offset < 2) {
527                         *reg &= ~0xffff;
528                         *reg |= orig & 0xffff;
529                 }
530
531                 vgic_update_state(vcpu->kvm);
532                 return true;
533         }
534
535         return false;
536 }
537
538 static bool handle_mmio_clear_pending_reg(struct kvm_vcpu *vcpu,
539                                           struct kvm_exit_mmio *mmio,
540                                           phys_addr_t offset)
541 {
542         u32 *level_active;
543         u32 *reg, orig;
544         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
545
546         reg = vgic_bitmap_get_reg(&dist->irq_pending, vcpu->vcpu_id, offset);
547         orig = *reg;
548         vgic_reg_access(mmio, reg, offset,
549                         ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
550         if (mmio->is_write) {
551                 /* Re-set level triggered level-active interrupts */
552                 level_active = vgic_bitmap_get_reg(&dist->irq_level,
553                                           vcpu->vcpu_id, offset);
554                 reg = vgic_bitmap_get_reg(&dist->irq_pending,
555                                           vcpu->vcpu_id, offset);
556                 *reg |= *level_active;
557
558                 /* Ignore writes to SGIs */
559                 if (offset < 2) {
560                         *reg &= ~0xffff;
561                         *reg |= orig & 0xffff;
562                 }
563
564                 /* Clear soft-pending flags */
565                 reg = vgic_bitmap_get_reg(&dist->irq_soft_pend,
566                                           vcpu->vcpu_id, offset);
567                 vgic_reg_access(mmio, reg, offset,
568                                 ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
569
570                 vgic_update_state(vcpu->kvm);
571                 return true;
572         }
573
574         return false;
575 }
576
577 static bool handle_mmio_priority_reg(struct kvm_vcpu *vcpu,
578                                      struct kvm_exit_mmio *mmio,
579                                      phys_addr_t offset)
580 {
581         u32 *reg = vgic_bytemap_get_reg(&vcpu->kvm->arch.vgic.irq_priority,
582                                         vcpu->vcpu_id, offset);
583         vgic_reg_access(mmio, reg, offset,
584                         ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
585         return false;
586 }
587
588 #define GICD_ITARGETSR_SIZE     32
589 #define GICD_CPUTARGETS_BITS    8
590 #define GICD_IRQS_PER_ITARGETSR (GICD_ITARGETSR_SIZE / GICD_CPUTARGETS_BITS)
591 static u32 vgic_get_target_reg(struct kvm *kvm, int irq)
592 {
593         struct vgic_dist *dist = &kvm->arch.vgic;
594         int i;
595         u32 val = 0;
596
597         irq -= VGIC_NR_PRIVATE_IRQS;
598
599         for (i = 0; i < GICD_IRQS_PER_ITARGETSR; i++)
600                 val |= 1 << (dist->irq_spi_cpu[irq + i] + i * 8);
601
602         return val;
603 }
604
605 static void vgic_set_target_reg(struct kvm *kvm, u32 val, int irq)
606 {
607         struct vgic_dist *dist = &kvm->arch.vgic;
608         struct kvm_vcpu *vcpu;
609         int i, c;
610         unsigned long *bmap;
611         u32 target;
612
613         irq -= VGIC_NR_PRIVATE_IRQS;
614
615         /*
616          * Pick the LSB in each byte. This ensures we target exactly
617          * one vcpu per IRQ. If the byte is null, assume we target
618          * CPU0.
619          */
620         for (i = 0; i < GICD_IRQS_PER_ITARGETSR; i++) {
621                 int shift = i * GICD_CPUTARGETS_BITS;
622                 target = ffs((val >> shift) & 0xffU);
623                 target = target ? (target - 1) : 0;
624                 dist->irq_spi_cpu[irq + i] = target;
625                 kvm_for_each_vcpu(c, vcpu, kvm) {
626                         bmap = vgic_bitmap_get_shared_map(&dist->irq_spi_target[c]);
627                         if (c == target)
628                                 set_bit(irq + i, bmap);
629                         else
630                                 clear_bit(irq + i, bmap);
631                 }
632         }
633 }
634
635 static bool handle_mmio_target_reg(struct kvm_vcpu *vcpu,
636                                    struct kvm_exit_mmio *mmio,
637                                    phys_addr_t offset)
638 {
639         u32 reg;
640
641         /* We treat the banked interrupts targets as read-only */
642         if (offset < 32) {
643                 u32 roreg = 1 << vcpu->vcpu_id;
644                 roreg |= roreg << 8;
645                 roreg |= roreg << 16;
646
647                 vgic_reg_access(mmio, &roreg, offset,
648                                 ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
649                 return false;
650         }
651
652         reg = vgic_get_target_reg(vcpu->kvm, offset & ~3U);
653         vgic_reg_access(mmio, &reg, offset,
654                         ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
655         if (mmio->is_write) {
656                 vgic_set_target_reg(vcpu->kvm, reg, offset & ~3U);
657                 vgic_update_state(vcpu->kvm);
658                 return true;
659         }
660
661         return false;
662 }
663
664 static u32 vgic_cfg_expand(u16 val)
665 {
666         u32 res = 0;
667         int i;
668
669         /*
670          * Turn a 16bit value like abcd...mnop into a 32bit word
671          * a0b0c0d0...m0n0o0p0, which is what the HW cfg register is.
672          */
673         for (i = 0; i < 16; i++)
674                 res |= ((val >> i) & VGIC_CFG_EDGE) << (2 * i + 1);
675
676         return res;
677 }
678
679 static u16 vgic_cfg_compress(u32 val)
680 {
681         u16 res = 0;
682         int i;
683
684         /*
685          * Turn a 32bit word a0b0c0d0...m0n0o0p0 into 16bit value like
686          * abcd...mnop which is what we really care about.
687          */
688         for (i = 0; i < 16; i++)
689                 res |= ((val >> (i * 2 + 1)) & VGIC_CFG_EDGE) << i;
690
691         return res;
692 }
693
694 /*
695  * The distributor uses 2 bits per IRQ for the CFG register, but the
696  * LSB is always 0. As such, we only keep the upper bit, and use the
697  * two above functions to compress/expand the bits
698  */
699 static bool handle_mmio_cfg_reg(struct kvm_vcpu *vcpu,
700                                 struct kvm_exit_mmio *mmio, phys_addr_t offset)
701 {
702         u32 val;
703         u32 *reg;
704
705         reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_cfg,
706                                   vcpu->vcpu_id, offset >> 1);
707
708         if (offset & 4)
709                 val = *reg >> 16;
710         else
711                 val = *reg & 0xffff;
712
713         val = vgic_cfg_expand(val);
714         vgic_reg_access(mmio, &val, offset,
715                         ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
716         if (mmio->is_write) {
717                 if (offset < 8) {
718                         *reg = ~0U; /* Force PPIs/SGIs to 1 */
719                         return false;
720                 }
721
722                 val = vgic_cfg_compress(val);
723                 if (offset & 4) {
724                         *reg &= 0xffff;
725                         *reg |= val << 16;
726                 } else {
727                         *reg &= 0xffff << 16;
728                         *reg |= val;
729                 }
730         }
731
732         return false;
733 }
734
735 static bool handle_mmio_sgi_reg(struct kvm_vcpu *vcpu,
736                                 struct kvm_exit_mmio *mmio, phys_addr_t offset)
737 {
738         u32 reg;
739         vgic_reg_access(mmio, &reg, offset,
740                         ACCESS_READ_RAZ | ACCESS_WRITE_VALUE);
741         if (mmio->is_write) {
742                 vgic_dispatch_sgi(vcpu, reg);
743                 vgic_update_state(vcpu->kvm);
744                 return true;
745         }
746
747         return false;
748 }
749
750 /**
751  * vgic_unqueue_irqs - move pending IRQs from LRs to the distributor
752  * @vgic_cpu: Pointer to the vgic_cpu struct holding the LRs
753  *
754  * Move any pending IRQs that have already been assigned to LRs back to the
755  * emulated distributor state so that the complete emulated state can be read
756  * from the main emulation structures without investigating the LRs.
757  *
758  * Note that IRQs in the active state in the LRs get their pending state moved
759  * to the distributor but the active state stays in the LRs, because we don't
760  * track the active state on the distributor side.
761  */
762 static void vgic_unqueue_irqs(struct kvm_vcpu *vcpu)
763 {
764         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
765         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
766         int vcpu_id = vcpu->vcpu_id;
767         int i;
768
769         for_each_set_bit(i, vgic_cpu->lr_used, vgic_cpu->nr_lr) {
770                 struct vgic_lr lr = vgic_get_lr(vcpu, i);
771
772                 /*
773                  * There are three options for the state bits:
774                  *
775                  * 01: pending
776                  * 10: active
777                  * 11: pending and active
778                  *
779                  * If the LR holds only an active interrupt (not pending) then
780                  * just leave it alone.
781                  */
782                 if ((lr.state & LR_STATE_MASK) == LR_STATE_ACTIVE)
783                         continue;
784
785                 /*
786                  * Reestablish the pending state on the distributor and the
787                  * CPU interface.  It may have already been pending, but that
788                  * is fine, then we are only setting a few bits that were
789                  * already set.
790                  */
791                 vgic_dist_irq_set_pending(vcpu, lr.irq);
792                 if (lr.irq < VGIC_NR_SGIS)
793                         *vgic_get_sgi_sources(dist, vcpu_id, lr.irq) |= 1 << lr.source;
794                 lr.state &= ~LR_STATE_PENDING;
795                 vgic_set_lr(vcpu, i, lr);
796
797                 /*
798                  * If there's no state left on the LR (it could still be
799                  * active), then the LR does not hold any useful info and can
800                  * be marked as free for other use.
801                  */
802                 if (!(lr.state & LR_STATE_MASK)) {
803                         vgic_retire_lr(i, lr.irq, vcpu);
804                         vgic_irq_clear_queued(vcpu, lr.irq);
805                 }
806
807                 /* Finally update the VGIC state. */
808                 vgic_update_state(vcpu->kvm);
809         }
810 }
811
812 /* Handle reads of GICD_CPENDSGIRn and GICD_SPENDSGIRn */
813 static bool read_set_clear_sgi_pend_reg(struct kvm_vcpu *vcpu,
814                                         struct kvm_exit_mmio *mmio,
815                                         phys_addr_t offset)
816 {
817         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
818         int sgi;
819         int min_sgi = (offset & ~0x3) * 4;
820         int max_sgi = min_sgi + 3;
821         int vcpu_id = vcpu->vcpu_id;
822         u32 reg = 0;
823
824         /* Copy source SGIs from distributor side */
825         for (sgi = min_sgi; sgi <= max_sgi; sgi++) {
826                 int shift = 8 * (sgi - min_sgi);
827                 reg |= ((u32)*vgic_get_sgi_sources(dist, vcpu_id, sgi)) << shift;
828         }
829
830         mmio_data_write(mmio, ~0, reg);
831         return false;
832 }
833
834 static bool write_set_clear_sgi_pend_reg(struct kvm_vcpu *vcpu,
835                                          struct kvm_exit_mmio *mmio,
836                                          phys_addr_t offset, bool set)
837 {
838         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
839         int sgi;
840         int min_sgi = (offset & ~0x3) * 4;
841         int max_sgi = min_sgi + 3;
842         int vcpu_id = vcpu->vcpu_id;
843         u32 reg;
844         bool updated = false;
845
846         reg = mmio_data_read(mmio, ~0);
847
848         /* Clear pending SGIs on the distributor */
849         for (sgi = min_sgi; sgi <= max_sgi; sgi++) {
850                 u8 mask = reg >> (8 * (sgi - min_sgi));
851                 u8 *src = vgic_get_sgi_sources(dist, vcpu_id, sgi);
852                 if (set) {
853                         if ((*src & mask) != mask)
854                                 updated = true;
855                         *src |= mask;
856                 } else {
857                         if (*src & mask)
858                                 updated = true;
859                         *src &= ~mask;
860                 }
861         }
862
863         if (updated)
864                 vgic_update_state(vcpu->kvm);
865
866         return updated;
867 }
868
869 static bool handle_mmio_sgi_set(struct kvm_vcpu *vcpu,
870                                 struct kvm_exit_mmio *mmio,
871                                 phys_addr_t offset)
872 {
873         if (!mmio->is_write)
874                 return read_set_clear_sgi_pend_reg(vcpu, mmio, offset);
875         else
876                 return write_set_clear_sgi_pend_reg(vcpu, mmio, offset, true);
877 }
878
879 static bool handle_mmio_sgi_clear(struct kvm_vcpu *vcpu,
880                                   struct kvm_exit_mmio *mmio,
881                                   phys_addr_t offset)
882 {
883         if (!mmio->is_write)
884                 return read_set_clear_sgi_pend_reg(vcpu, mmio, offset);
885         else
886                 return write_set_clear_sgi_pend_reg(vcpu, mmio, offset, false);
887 }
888
889 /*
890  * I would have liked to use the kvm_bus_io_*() API instead, but it
891  * cannot cope with banked registers (only the VM pointer is passed
892  * around, and we need the vcpu). One of these days, someone please
893  * fix it!
894  */
895 struct mmio_range {
896         phys_addr_t base;
897         unsigned long len;
898         bool (*handle_mmio)(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
899                             phys_addr_t offset);
900 };
901
902 static const struct mmio_range vgic_dist_ranges[] = {
903         {
904                 .base           = GIC_DIST_CTRL,
905                 .len            = 12,
906                 .handle_mmio    = handle_mmio_misc,
907         },
908         {
909                 .base           = GIC_DIST_IGROUP,
910                 .len            = VGIC_NR_IRQS / 8,
911                 .handle_mmio    = handle_mmio_raz_wi,
912         },
913         {
914                 .base           = GIC_DIST_ENABLE_SET,
915                 .len            = VGIC_NR_IRQS / 8,
916                 .handle_mmio    = handle_mmio_set_enable_reg,
917         },
918         {
919                 .base           = GIC_DIST_ENABLE_CLEAR,
920                 .len            = VGIC_NR_IRQS / 8,
921                 .handle_mmio    = handle_mmio_clear_enable_reg,
922         },
923         {
924                 .base           = GIC_DIST_PENDING_SET,
925                 .len            = VGIC_NR_IRQS / 8,
926                 .handle_mmio    = handle_mmio_set_pending_reg,
927         },
928         {
929                 .base           = GIC_DIST_PENDING_CLEAR,
930                 .len            = VGIC_NR_IRQS / 8,
931                 .handle_mmio    = handle_mmio_clear_pending_reg,
932         },
933         {
934                 .base           = GIC_DIST_ACTIVE_SET,
935                 .len            = VGIC_NR_IRQS / 8,
936                 .handle_mmio    = handle_mmio_raz_wi,
937         },
938         {
939                 .base           = GIC_DIST_ACTIVE_CLEAR,
940                 .len            = VGIC_NR_IRQS / 8,
941                 .handle_mmio    = handle_mmio_raz_wi,
942         },
943         {
944                 .base           = GIC_DIST_PRI,
945                 .len            = VGIC_NR_IRQS,
946                 .handle_mmio    = handle_mmio_priority_reg,
947         },
948         {
949                 .base           = GIC_DIST_TARGET,
950                 .len            = VGIC_NR_IRQS,
951                 .handle_mmio    = handle_mmio_target_reg,
952         },
953         {
954                 .base           = GIC_DIST_CONFIG,
955                 .len            = VGIC_NR_IRQS / 4,
956                 .handle_mmio    = handle_mmio_cfg_reg,
957         },
958         {
959                 .base           = GIC_DIST_SOFTINT,
960                 .len            = 4,
961                 .handle_mmio    = handle_mmio_sgi_reg,
962         },
963         {
964                 .base           = GIC_DIST_SGI_PENDING_CLEAR,
965                 .len            = VGIC_NR_SGIS,
966                 .handle_mmio    = handle_mmio_sgi_clear,
967         },
968         {
969                 .base           = GIC_DIST_SGI_PENDING_SET,
970                 .len            = VGIC_NR_SGIS,
971                 .handle_mmio    = handle_mmio_sgi_set,
972         },
973         {}
974 };
975
976 static const
977 struct mmio_range *find_matching_range(const struct mmio_range *ranges,
978                                        struct kvm_exit_mmio *mmio,
979                                        phys_addr_t offset)
980 {
981         const struct mmio_range *r = ranges;
982
983         while (r->len) {
984                 if (offset >= r->base &&
985                     (offset + mmio->len) <= (r->base + r->len))
986                         return r;
987                 r++;
988         }
989
990         return NULL;
991 }
992
993 /**
994  * vgic_handle_mmio - handle an in-kernel MMIO access
995  * @vcpu:       pointer to the vcpu performing the access
996  * @run:        pointer to the kvm_run structure
997  * @mmio:       pointer to the data describing the access
998  *
999  * returns true if the MMIO access has been performed in kernel space,
1000  * and false if it needs to be emulated in user space.
1001  */
1002 bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
1003                       struct kvm_exit_mmio *mmio)
1004 {
1005         const struct mmio_range *range;
1006         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1007         unsigned long base = dist->vgic_dist_base;
1008         bool updated_state;
1009         unsigned long offset;
1010
1011         if (!irqchip_in_kernel(vcpu->kvm) ||
1012             mmio->phys_addr < base ||
1013             (mmio->phys_addr + mmio->len) > (base + KVM_VGIC_V2_DIST_SIZE))
1014                 return false;
1015
1016         /* We don't support ldrd / strd or ldm / stm to the emulated vgic */
1017         if (mmio->len > 4) {
1018                 kvm_inject_dabt(vcpu, mmio->phys_addr);
1019                 return true;
1020         }
1021
1022         offset = mmio->phys_addr - base;
1023         range = find_matching_range(vgic_dist_ranges, mmio, offset);
1024         if (unlikely(!range || !range->handle_mmio)) {
1025                 pr_warn("Unhandled access %d %08llx %d\n",
1026                         mmio->is_write, mmio->phys_addr, mmio->len);
1027                 return false;
1028         }
1029
1030         spin_lock(&vcpu->kvm->arch.vgic.lock);
1031         offset = mmio->phys_addr - range->base - base;
1032         updated_state = range->handle_mmio(vcpu, mmio, offset);
1033         spin_unlock(&vcpu->kvm->arch.vgic.lock);
1034         kvm_prepare_mmio(run, mmio);
1035         kvm_handle_mmio_return(vcpu, run);
1036
1037         if (updated_state)
1038                 vgic_kick_vcpus(vcpu->kvm);
1039
1040         return true;
1041 }
1042
1043 static u8 *vgic_get_sgi_sources(struct vgic_dist *dist, int vcpu_id, int sgi)
1044 {
1045         return dist->irq_sgi_sources + vcpu_id * VGIC_NR_SGIS + sgi;
1046 }
1047
1048 static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg)
1049 {
1050         struct kvm *kvm = vcpu->kvm;
1051         struct vgic_dist *dist = &kvm->arch.vgic;
1052         int nrcpus = atomic_read(&kvm->online_vcpus);
1053         u8 target_cpus;
1054         int sgi, mode, c, vcpu_id;
1055
1056         vcpu_id = vcpu->vcpu_id;
1057
1058         sgi = reg & 0xf;
1059         target_cpus = (reg >> 16) & 0xff;
1060         mode = (reg >> 24) & 3;
1061
1062         switch (mode) {
1063         case 0:
1064                 if (!target_cpus)
1065                         return;
1066                 break;
1067
1068         case 1:
1069                 target_cpus = ((1 << nrcpus) - 1) & ~(1 << vcpu_id) & 0xff;
1070                 break;
1071
1072         case 2:
1073                 target_cpus = 1 << vcpu_id;
1074                 break;
1075         }
1076
1077         kvm_for_each_vcpu(c, vcpu, kvm) {
1078                 if (target_cpus & 1) {
1079                         /* Flag the SGI as pending */
1080                         vgic_dist_irq_set_pending(vcpu, sgi);
1081                         *vgic_get_sgi_sources(dist, c, sgi) |= 1 << vcpu_id;
1082                         kvm_debug("SGI%d from CPU%d to CPU%d\n", sgi, vcpu_id, c);
1083                 }
1084
1085                 target_cpus >>= 1;
1086         }
1087 }
1088
1089 static int vgic_nr_shared_irqs(struct vgic_dist *dist)
1090 {
1091         return dist->nr_irqs - VGIC_NR_PRIVATE_IRQS;
1092 }
1093
1094 static int compute_pending_for_cpu(struct kvm_vcpu *vcpu)
1095 {
1096         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1097         unsigned long *pending, *enabled, *pend_percpu, *pend_shared;
1098         unsigned long pending_private, pending_shared;
1099         int nr_shared = vgic_nr_shared_irqs(dist);
1100         int vcpu_id;
1101
1102         vcpu_id = vcpu->vcpu_id;
1103         pend_percpu = vcpu->arch.vgic_cpu.pending_percpu;
1104         pend_shared = vcpu->arch.vgic_cpu.pending_shared;
1105
1106         pending = vgic_bitmap_get_cpu_map(&dist->irq_pending, vcpu_id);
1107         enabled = vgic_bitmap_get_cpu_map(&dist->irq_enabled, vcpu_id);
1108         bitmap_and(pend_percpu, pending, enabled, VGIC_NR_PRIVATE_IRQS);
1109
1110         pending = vgic_bitmap_get_shared_map(&dist->irq_pending);
1111         enabled = vgic_bitmap_get_shared_map(&dist->irq_enabled);
1112         bitmap_and(pend_shared, pending, enabled, nr_shared);
1113         bitmap_and(pend_shared, pend_shared,
1114                    vgic_bitmap_get_shared_map(&dist->irq_spi_target[vcpu_id]),
1115                    nr_shared);
1116
1117         pending_private = find_first_bit(pend_percpu, VGIC_NR_PRIVATE_IRQS);
1118         pending_shared = find_first_bit(pend_shared, nr_shared);
1119         return (pending_private < VGIC_NR_PRIVATE_IRQS ||
1120                 pending_shared < vgic_nr_shared_irqs(dist));
1121 }
1122
1123 /*
1124  * Update the interrupt state and determine which CPUs have pending
1125  * interrupts. Must be called with distributor lock held.
1126  */
1127 static void vgic_update_state(struct kvm *kvm)
1128 {
1129         struct vgic_dist *dist = &kvm->arch.vgic;
1130         struct kvm_vcpu *vcpu;
1131         int c;
1132
1133         if (!dist->enabled) {
1134                 set_bit(0, dist->irq_pending_on_cpu);
1135                 return;
1136         }
1137
1138         kvm_for_each_vcpu(c, vcpu, kvm) {
1139                 if (compute_pending_for_cpu(vcpu)) {
1140                         pr_debug("CPU%d has pending interrupts\n", c);
1141                         set_bit(c, dist->irq_pending_on_cpu);
1142                 }
1143         }
1144 }
1145
1146 static struct vgic_lr vgic_get_lr(const struct kvm_vcpu *vcpu, int lr)
1147 {
1148         return vgic_ops->get_lr(vcpu, lr);
1149 }
1150
1151 static void vgic_set_lr(struct kvm_vcpu *vcpu, int lr,
1152                                struct vgic_lr vlr)
1153 {
1154         vgic_ops->set_lr(vcpu, lr, vlr);
1155 }
1156
1157 static void vgic_sync_lr_elrsr(struct kvm_vcpu *vcpu, int lr,
1158                                struct vgic_lr vlr)
1159 {
1160         vgic_ops->sync_lr_elrsr(vcpu, lr, vlr);
1161 }
1162
1163 static inline u64 vgic_get_elrsr(struct kvm_vcpu *vcpu)
1164 {
1165         return vgic_ops->get_elrsr(vcpu);
1166 }
1167
1168 static inline u64 vgic_get_eisr(struct kvm_vcpu *vcpu)
1169 {
1170         return vgic_ops->get_eisr(vcpu);
1171 }
1172
1173 static inline u32 vgic_get_interrupt_status(struct kvm_vcpu *vcpu)
1174 {
1175         return vgic_ops->get_interrupt_status(vcpu);
1176 }
1177
1178 static inline void vgic_enable_underflow(struct kvm_vcpu *vcpu)
1179 {
1180         vgic_ops->enable_underflow(vcpu);
1181 }
1182
1183 static inline void vgic_disable_underflow(struct kvm_vcpu *vcpu)
1184 {
1185         vgic_ops->disable_underflow(vcpu);
1186 }
1187
1188 static inline void vgic_get_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
1189 {
1190         vgic_ops->get_vmcr(vcpu, vmcr);
1191 }
1192
1193 static void vgic_set_vmcr(struct kvm_vcpu *vcpu, struct vgic_vmcr *vmcr)
1194 {
1195         vgic_ops->set_vmcr(vcpu, vmcr);
1196 }
1197
1198 static inline void vgic_enable(struct kvm_vcpu *vcpu)
1199 {
1200         vgic_ops->enable(vcpu);
1201 }
1202
1203 static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu)
1204 {
1205         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1206         struct vgic_lr vlr = vgic_get_lr(vcpu, lr_nr);
1207
1208         vlr.state = 0;
1209         vgic_set_lr(vcpu, lr_nr, vlr);
1210         clear_bit(lr_nr, vgic_cpu->lr_used);
1211         vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
1212 }
1213
1214 /*
1215  * An interrupt may have been disabled after being made pending on the
1216  * CPU interface (the classic case is a timer running while we're
1217  * rebooting the guest - the interrupt would kick as soon as the CPU
1218  * interface gets enabled, with deadly consequences).
1219  *
1220  * The solution is to examine already active LRs, and check the
1221  * interrupt is still enabled. If not, just retire it.
1222  */
1223 static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu)
1224 {
1225         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1226         int lr;
1227
1228         for_each_set_bit(lr, vgic_cpu->lr_used, vgic->nr_lr) {
1229                 struct vgic_lr vlr = vgic_get_lr(vcpu, lr);
1230
1231                 if (!vgic_irq_is_enabled(vcpu, vlr.irq)) {
1232                         vgic_retire_lr(lr, vlr.irq, vcpu);
1233                         if (vgic_irq_is_queued(vcpu, vlr.irq))
1234                                 vgic_irq_clear_queued(vcpu, vlr.irq);
1235                 }
1236         }
1237 }
1238
1239 /*
1240  * Queue an interrupt to a CPU virtual interface. Return true on success,
1241  * or false if it wasn't possible to queue it.
1242  */
1243 static bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
1244 {
1245         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1246         struct vgic_lr vlr;
1247         int lr;
1248
1249         /* Sanitize the input... */
1250         BUG_ON(sgi_source_id & ~7);
1251         BUG_ON(sgi_source_id && irq >= VGIC_NR_SGIS);
1252         BUG_ON(irq >= VGIC_NR_IRQS);
1253
1254         kvm_debug("Queue IRQ%d\n", irq);
1255
1256         lr = vgic_cpu->vgic_irq_lr_map[irq];
1257
1258         /* Do we have an active interrupt for the same CPUID? */
1259         if (lr != LR_EMPTY) {
1260                 vlr = vgic_get_lr(vcpu, lr);
1261                 if (vlr.source == sgi_source_id) {
1262                         kvm_debug("LR%d piggyback for IRQ%d\n", lr, vlr.irq);
1263                         BUG_ON(!test_bit(lr, vgic_cpu->lr_used));
1264                         vlr.state |= LR_STATE_PENDING;
1265                         vgic_set_lr(vcpu, lr, vlr);
1266                         return true;
1267                 }
1268         }
1269
1270         /* Try to use another LR for this interrupt */
1271         lr = find_first_zero_bit((unsigned long *)vgic_cpu->lr_used,
1272                                vgic->nr_lr);
1273         if (lr >= vgic->nr_lr)
1274                 return false;
1275
1276         kvm_debug("LR%d allocated for IRQ%d %x\n", lr, irq, sgi_source_id);
1277         vgic_cpu->vgic_irq_lr_map[irq] = lr;
1278         set_bit(lr, vgic_cpu->lr_used);
1279
1280         vlr.irq = irq;
1281         vlr.source = sgi_source_id;
1282         vlr.state = LR_STATE_PENDING;
1283         if (!vgic_irq_is_edge(vcpu, irq))
1284                 vlr.state |= LR_EOI_INT;
1285
1286         vgic_set_lr(vcpu, lr, vlr);
1287
1288         return true;
1289 }
1290
1291 static bool vgic_queue_sgi(struct kvm_vcpu *vcpu, int irq)
1292 {
1293         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1294         unsigned long sources;
1295         int vcpu_id = vcpu->vcpu_id;
1296         int c;
1297
1298         sources = *vgic_get_sgi_sources(dist, vcpu_id, irq);
1299
1300         for_each_set_bit(c, &sources, VGIC_MAX_CPUS) {
1301                 if (vgic_queue_irq(vcpu, c, irq))
1302                         clear_bit(c, &sources);
1303         }
1304
1305         *vgic_get_sgi_sources(dist, vcpu_id, irq) = sources;
1306
1307         /*
1308          * If the sources bitmap has been cleared it means that we
1309          * could queue all the SGIs onto link registers (see the
1310          * clear_bit above), and therefore we are done with them in
1311          * our emulated gic and can get rid of them.
1312          */
1313         if (!sources) {
1314                 vgic_dist_irq_clear_pending(vcpu, irq);
1315                 vgic_cpu_irq_clear(vcpu, irq);
1316                 return true;
1317         }
1318
1319         return false;
1320 }
1321
1322 static bool vgic_queue_hwirq(struct kvm_vcpu *vcpu, int irq)
1323 {
1324         if (!vgic_can_sample_irq(vcpu, irq))
1325                 return true; /* level interrupt, already queued */
1326
1327         if (vgic_queue_irq(vcpu, 0, irq)) {
1328                 if (vgic_irq_is_edge(vcpu, irq)) {
1329                         vgic_dist_irq_clear_pending(vcpu, irq);
1330                         vgic_cpu_irq_clear(vcpu, irq);
1331                 } else {
1332                         vgic_irq_set_queued(vcpu, irq);
1333                 }
1334
1335                 return true;
1336         }
1337
1338         return false;
1339 }
1340
1341 /*
1342  * Fill the list registers with pending interrupts before running the
1343  * guest.
1344  */
1345 static void __kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
1346 {
1347         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1348         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1349         int i, vcpu_id;
1350         int overflow = 0;
1351
1352         vcpu_id = vcpu->vcpu_id;
1353
1354         /*
1355          * We may not have any pending interrupt, or the interrupts
1356          * may have been serviced from another vcpu. In all cases,
1357          * move along.
1358          */
1359         if (!kvm_vgic_vcpu_pending_irq(vcpu)) {
1360                 pr_debug("CPU%d has no pending interrupt\n", vcpu_id);
1361                 goto epilog;
1362         }
1363
1364         /* SGIs */
1365         for_each_set_bit(i, vgic_cpu->pending_percpu, VGIC_NR_SGIS) {
1366                 if (!vgic_queue_sgi(vcpu, i))
1367                         overflow = 1;
1368         }
1369
1370         /* PPIs */
1371         for_each_set_bit_from(i, vgic_cpu->pending_percpu, VGIC_NR_PRIVATE_IRQS) {
1372                 if (!vgic_queue_hwirq(vcpu, i))
1373                         overflow = 1;
1374         }
1375
1376         /* SPIs */
1377         for_each_set_bit(i, vgic_cpu->pending_shared, vgic_nr_shared_irqs(dist)) {
1378                 if (!vgic_queue_hwirq(vcpu, i + VGIC_NR_PRIVATE_IRQS))
1379                         overflow = 1;
1380         }
1381
1382 epilog:
1383         if (overflow) {
1384                 vgic_enable_underflow(vcpu);
1385         } else {
1386                 vgic_disable_underflow(vcpu);
1387                 /*
1388                  * We're about to run this VCPU, and we've consumed
1389                  * everything the distributor had in store for
1390                  * us. Claim we don't have anything pending. We'll
1391                  * adjust that if needed while exiting.
1392                  */
1393                 clear_bit(vcpu_id, dist->irq_pending_on_cpu);
1394         }
1395 }
1396
1397 static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
1398 {
1399         u32 status = vgic_get_interrupt_status(vcpu);
1400         bool level_pending = false;
1401
1402         kvm_debug("STATUS = %08x\n", status);
1403
1404         if (status & INT_STATUS_EOI) {
1405                 /*
1406                  * Some level interrupts have been EOIed. Clear their
1407                  * active bit.
1408                  */
1409                 u64 eisr = vgic_get_eisr(vcpu);
1410                 unsigned long *eisr_ptr = (unsigned long *)&eisr;
1411                 int lr;
1412
1413                 for_each_set_bit(lr, eisr_ptr, vgic->nr_lr) {
1414                         struct vgic_lr vlr = vgic_get_lr(vcpu, lr);
1415                         WARN_ON(vgic_irq_is_edge(vcpu, vlr.irq));
1416
1417                         vgic_irq_clear_queued(vcpu, vlr.irq);
1418                         WARN_ON(vlr.state & LR_STATE_MASK);
1419                         vlr.state = 0;
1420                         vgic_set_lr(vcpu, lr, vlr);
1421
1422                         /*
1423                          * If the IRQ was EOIed it was also ACKed and we we
1424                          * therefore assume we can clear the soft pending
1425                          * state (should it had been set) for this interrupt.
1426                          *
1427                          * Note: if the IRQ soft pending state was set after
1428                          * the IRQ was acked, it actually shouldn't be
1429                          * cleared, but we have no way of knowing that unless
1430                          * we start trapping ACKs when the soft-pending state
1431                          * is set.
1432                          */
1433                         vgic_dist_irq_clear_soft_pend(vcpu, vlr.irq);
1434
1435                         /* Any additional pending interrupt? */
1436                         if (vgic_dist_irq_get_level(vcpu, vlr.irq)) {
1437                                 vgic_cpu_irq_set(vcpu, vlr.irq);
1438                                 level_pending = true;
1439                         } else {
1440                                 vgic_dist_irq_clear_pending(vcpu, vlr.irq);
1441                                 vgic_cpu_irq_clear(vcpu, vlr.irq);
1442                         }
1443
1444                         /*
1445                          * Despite being EOIed, the LR may not have
1446                          * been marked as empty.
1447                          */
1448                         vgic_sync_lr_elrsr(vcpu, lr, vlr);
1449                 }
1450         }
1451
1452         if (status & INT_STATUS_UNDERFLOW)
1453                 vgic_disable_underflow(vcpu);
1454
1455         return level_pending;
1456 }
1457
1458 /*
1459  * Sync back the VGIC state after a guest run. The distributor lock is
1460  * needed so we don't get preempted in the middle of the state processing.
1461  */
1462 static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
1463 {
1464         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1465         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1466         u64 elrsr;
1467         unsigned long *elrsr_ptr;
1468         int lr, pending;
1469         bool level_pending;
1470
1471         level_pending = vgic_process_maintenance(vcpu);
1472         elrsr = vgic_get_elrsr(vcpu);
1473         elrsr_ptr = (unsigned long *)&elrsr;
1474
1475         /* Clear mappings for empty LRs */
1476         for_each_set_bit(lr, elrsr_ptr, vgic->nr_lr) {
1477                 struct vgic_lr vlr;
1478
1479                 if (!test_and_clear_bit(lr, vgic_cpu->lr_used))
1480                         continue;
1481
1482                 vlr = vgic_get_lr(vcpu, lr);
1483
1484                 BUG_ON(vlr.irq >= VGIC_NR_IRQS);
1485                 vgic_cpu->vgic_irq_lr_map[vlr.irq] = LR_EMPTY;
1486         }
1487
1488         /* Check if we still have something up our sleeve... */
1489         pending = find_first_zero_bit(elrsr_ptr, vgic->nr_lr);
1490         if (level_pending || pending < vgic->nr_lr)
1491                 set_bit(vcpu->vcpu_id, dist->irq_pending_on_cpu);
1492 }
1493
1494 void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
1495 {
1496         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1497
1498         if (!irqchip_in_kernel(vcpu->kvm))
1499                 return;
1500
1501         spin_lock(&dist->lock);
1502         __kvm_vgic_flush_hwstate(vcpu);
1503         spin_unlock(&dist->lock);
1504 }
1505
1506 void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
1507 {
1508         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1509
1510         if (!irqchip_in_kernel(vcpu->kvm))
1511                 return;
1512
1513         spin_lock(&dist->lock);
1514         __kvm_vgic_sync_hwstate(vcpu);
1515         spin_unlock(&dist->lock);
1516 }
1517
1518 int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
1519 {
1520         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1521
1522         if (!irqchip_in_kernel(vcpu->kvm))
1523                 return 0;
1524
1525         return test_bit(vcpu->vcpu_id, dist->irq_pending_on_cpu);
1526 }
1527
1528 static void vgic_kick_vcpus(struct kvm *kvm)
1529 {
1530         struct kvm_vcpu *vcpu;
1531         int c;
1532
1533         /*
1534          * We've injected an interrupt, time to find out who deserves
1535          * a good kick...
1536          */
1537         kvm_for_each_vcpu(c, vcpu, kvm) {
1538                 if (kvm_vgic_vcpu_pending_irq(vcpu))
1539                         kvm_vcpu_kick(vcpu);
1540         }
1541 }
1542
1543 static int vgic_validate_injection(struct kvm_vcpu *vcpu, int irq, int level)
1544 {
1545         int edge_triggered = vgic_irq_is_edge(vcpu, irq);
1546
1547         /*
1548          * Only inject an interrupt if:
1549          * - edge triggered and we have a rising edge
1550          * - level triggered and we change level
1551          */
1552         if (edge_triggered) {
1553                 int state = vgic_dist_irq_is_pending(vcpu, irq);
1554                 return level > state;
1555         } else {
1556                 int state = vgic_dist_irq_get_level(vcpu, irq);
1557                 return level != state;
1558         }
1559 }
1560
1561 static bool vgic_update_irq_pending(struct kvm *kvm, int cpuid,
1562                                   unsigned int irq_num, bool level)
1563 {
1564         struct vgic_dist *dist = &kvm->arch.vgic;
1565         struct kvm_vcpu *vcpu;
1566         int edge_triggered, level_triggered;
1567         int enabled;
1568         bool ret = true;
1569
1570         spin_lock(&dist->lock);
1571
1572         vcpu = kvm_get_vcpu(kvm, cpuid);
1573         edge_triggered = vgic_irq_is_edge(vcpu, irq_num);
1574         level_triggered = !edge_triggered;
1575
1576         if (!vgic_validate_injection(vcpu, irq_num, level)) {
1577                 ret = false;
1578                 goto out;
1579         }
1580
1581         if (irq_num >= VGIC_NR_PRIVATE_IRQS) {
1582                 cpuid = dist->irq_spi_cpu[irq_num - VGIC_NR_PRIVATE_IRQS];
1583                 vcpu = kvm_get_vcpu(kvm, cpuid);
1584         }
1585
1586         kvm_debug("Inject IRQ%d level %d CPU%d\n", irq_num, level, cpuid);
1587
1588         if (level) {
1589                 if (level_triggered)
1590                         vgic_dist_irq_set_level(vcpu, irq_num);
1591                 vgic_dist_irq_set_pending(vcpu, irq_num);
1592         } else {
1593                 if (level_triggered) {
1594                         vgic_dist_irq_clear_level(vcpu, irq_num);
1595                         if (!vgic_dist_irq_soft_pend(vcpu, irq_num))
1596                                 vgic_dist_irq_clear_pending(vcpu, irq_num);
1597                 } else {
1598                         vgic_dist_irq_clear_pending(vcpu, irq_num);
1599                 }
1600         }
1601
1602         enabled = vgic_irq_is_enabled(vcpu, irq_num);
1603
1604         if (!enabled) {
1605                 ret = false;
1606                 goto out;
1607         }
1608
1609         if (!vgic_can_sample_irq(vcpu, irq_num)) {
1610                 /*
1611                  * Level interrupt in progress, will be picked up
1612                  * when EOId.
1613                  */
1614                 ret = false;
1615                 goto out;
1616         }
1617
1618         if (level) {
1619                 vgic_cpu_irq_set(vcpu, irq_num);
1620                 set_bit(cpuid, dist->irq_pending_on_cpu);
1621         }
1622
1623 out:
1624         spin_unlock(&dist->lock);
1625
1626         return ret;
1627 }
1628
1629 /**
1630  * kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic
1631  * @kvm:     The VM structure pointer
1632  * @cpuid:   The CPU for PPIs
1633  * @irq_num: The IRQ number that is assigned to the device
1634  * @level:   Edge-triggered:  true:  to trigger the interrupt
1635  *                            false: to ignore the call
1636  *           Level-sensitive  true:  activates an interrupt
1637  *                            false: deactivates an interrupt
1638  *
1639  * The GIC is not concerned with devices being active-LOW or active-HIGH for
1640  * level-sensitive interrupts.  You can think of the level parameter as 1
1641  * being HIGH and 0 being LOW and all devices being active-HIGH.
1642  */
1643 int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
1644                         bool level)
1645 {
1646         if (likely(vgic_initialized(kvm)) &&
1647             vgic_update_irq_pending(kvm, cpuid, irq_num, level))
1648                 vgic_kick_vcpus(kvm);
1649
1650         return 0;
1651 }
1652
1653 static irqreturn_t vgic_maintenance_handler(int irq, void *data)
1654 {
1655         /*
1656          * We cannot rely on the vgic maintenance interrupt to be
1657          * delivered synchronously. This means we can only use it to
1658          * exit the VM, and we perform the handling of EOIed
1659          * interrupts on the exit path (see vgic_process_maintenance).
1660          */
1661         return IRQ_HANDLED;
1662 }
1663
1664 void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
1665 {
1666         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1667
1668         kfree(vgic_cpu->pending_shared);
1669         kfree(vgic_cpu->vgic_irq_lr_map);
1670         vgic_cpu->pending_shared = NULL;
1671         vgic_cpu->vgic_irq_lr_map = NULL;
1672 }
1673
1674 static int vgic_vcpu_init_maps(struct kvm_vcpu *vcpu, int nr_irqs)
1675 {
1676         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1677
1678         int sz = (nr_irqs - VGIC_NR_PRIVATE_IRQS) / 8;
1679         vgic_cpu->pending_shared = kzalloc(sz, GFP_KERNEL);
1680         vgic_cpu->vgic_irq_lr_map = kzalloc(nr_irqs, GFP_KERNEL);
1681
1682         if (!vgic_cpu->pending_shared || !vgic_cpu->vgic_irq_lr_map) {
1683                 kvm_vgic_vcpu_destroy(vcpu);
1684                 return -ENOMEM;
1685         }
1686
1687         return 0;
1688 }
1689
1690 /**
1691  * kvm_vgic_vcpu_init - Initialize per-vcpu VGIC state
1692  * @vcpu: pointer to the vcpu struct
1693  *
1694  * Initialize the vgic_cpu struct and vgic_dist struct fields pertaining to
1695  * this vcpu and enable the VGIC for this VCPU
1696  */
1697 int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
1698 {
1699         struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
1700         struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
1701         int i;
1702
1703         if (vcpu->vcpu_id >= VGIC_MAX_CPUS)
1704                 return -EBUSY;
1705
1706         for (i = 0; i < VGIC_NR_IRQS; i++) {
1707                 if (i < VGIC_NR_PPIS)
1708                         vgic_bitmap_set_irq_val(&dist->irq_enabled,
1709                                                 vcpu->vcpu_id, i, 1);
1710                 if (i < VGIC_NR_PRIVATE_IRQS)
1711                         vgic_bitmap_set_irq_val(&dist->irq_cfg,
1712                                                 vcpu->vcpu_id, i, VGIC_CFG_EDGE);
1713
1714                 vgic_cpu->vgic_irq_lr_map[i] = LR_EMPTY;
1715         }
1716
1717         /*
1718          * Store the number of LRs per vcpu, so we don't have to go
1719          * all the way to the distributor structure to find out. Only
1720          * assembly code should use this one.
1721          */
1722         vgic_cpu->nr_lr = vgic->nr_lr;
1723
1724         vgic_enable(vcpu);
1725
1726         return 0;
1727 }
1728
1729 void kvm_vgic_destroy(struct kvm *kvm)
1730 {
1731         struct vgic_dist *dist = &kvm->arch.vgic;
1732         struct kvm_vcpu *vcpu;
1733         int i;
1734
1735         kvm_for_each_vcpu(i, vcpu, kvm)
1736                 kvm_vgic_vcpu_destroy(vcpu);
1737
1738         vgic_free_bitmap(&dist->irq_enabled);
1739         vgic_free_bitmap(&dist->irq_level);
1740         vgic_free_bitmap(&dist->irq_pending);
1741         vgic_free_bitmap(&dist->irq_soft_pend);
1742         vgic_free_bitmap(&dist->irq_queued);
1743         vgic_free_bitmap(&dist->irq_cfg);
1744         vgic_free_bytemap(&dist->irq_priority);
1745         if (dist->irq_spi_target) {
1746                 for (i = 0; i < dist->nr_cpus; i++)
1747                         vgic_free_bitmap(&dist->irq_spi_target[i]);
1748         }
1749         kfree(dist->irq_sgi_sources);
1750         kfree(dist->irq_spi_cpu);
1751         kfree(dist->irq_spi_target);
1752         kfree(dist->irq_pending_on_cpu);
1753         dist->irq_sgi_sources = NULL;
1754         dist->irq_spi_cpu = NULL;
1755         dist->irq_spi_target = NULL;
1756         dist->irq_pending_on_cpu = NULL;
1757 }
1758
1759 /*
1760  * Allocate and initialize the various data structures. Must be called
1761  * with kvm->lock held!
1762  */
1763 static int vgic_init_maps(struct kvm *kvm)
1764 {
1765         struct vgic_dist *dist = &kvm->arch.vgic;
1766         struct kvm_vcpu *vcpu;
1767         int nr_cpus, nr_irqs;
1768         int ret, i;
1769
1770         nr_cpus = dist->nr_cpus = VGIC_MAX_CPUS;
1771         nr_irqs = dist->nr_irqs = VGIC_NR_IRQS;
1772
1773         ret  = vgic_init_bitmap(&dist->irq_enabled, nr_cpus, nr_irqs);
1774         ret |= vgic_init_bitmap(&dist->irq_level, nr_cpus, nr_irqs);
1775         ret |= vgic_init_bitmap(&dist->irq_pending, nr_cpus, nr_irqs);
1776         ret |= vgic_init_bitmap(&dist->irq_soft_pend, nr_cpus, nr_irqs);
1777         ret |= vgic_init_bitmap(&dist->irq_queued, nr_cpus, nr_irqs);
1778         ret |= vgic_init_bitmap(&dist->irq_cfg, nr_cpus, nr_irqs);
1779         ret |= vgic_init_bytemap(&dist->irq_priority, nr_cpus, nr_irqs);
1780
1781         if (ret)
1782                 goto out;
1783
1784         dist->irq_sgi_sources = kzalloc(nr_cpus * VGIC_NR_SGIS, GFP_KERNEL);
1785         dist->irq_spi_cpu = kzalloc(nr_irqs - VGIC_NR_PRIVATE_IRQS, GFP_KERNEL);
1786         dist->irq_spi_target = kzalloc(sizeof(*dist->irq_spi_target) * nr_cpus,
1787                                        GFP_KERNEL);
1788         dist->irq_pending_on_cpu = kzalloc(BITS_TO_LONGS(nr_cpus) * sizeof(long),
1789                                            GFP_KERNEL);
1790         if (!dist->irq_sgi_sources ||
1791             !dist->irq_spi_cpu ||
1792             !dist->irq_spi_target ||
1793             !dist->irq_pending_on_cpu) {
1794                 ret = -ENOMEM;
1795                 goto out;
1796         }
1797
1798         for (i = 0; i < nr_cpus; i++)
1799                 ret |= vgic_init_bitmap(&dist->irq_spi_target[i],
1800                                         nr_cpus, nr_irqs);
1801
1802         if (ret)
1803                 goto out;
1804
1805         kvm_for_each_vcpu(i, vcpu, kvm) {
1806                 ret = vgic_vcpu_init_maps(vcpu, nr_irqs);
1807                 if (ret) {
1808                         kvm_err("VGIC: Failed to allocate vcpu memory\n");
1809                         break;
1810                 }
1811         }
1812
1813 out:
1814         if (ret)
1815                 kvm_vgic_destroy(kvm);
1816
1817         return ret;
1818 }
1819
1820 /**
1821  * kvm_vgic_init - Initialize global VGIC state before running any VCPUs
1822  * @kvm: pointer to the kvm struct
1823  *
1824  * Map the virtual CPU interface into the VM before running any VCPUs.  We
1825  * can't do this at creation time, because user space must first set the
1826  * virtual CPU interface address in the guest physical address space.  Also
1827  * initialize the ITARGETSRn regs to 0 on the emulated distributor.
1828  */
1829 int kvm_vgic_init(struct kvm *kvm)
1830 {
1831         int ret = 0, i;
1832
1833         if (!irqchip_in_kernel(kvm))
1834                 return 0;
1835
1836         mutex_lock(&kvm->lock);
1837
1838         if (vgic_initialized(kvm))
1839                 goto out;
1840
1841         if (IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_dist_base) ||
1842             IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_cpu_base)) {
1843                 kvm_err("Need to set vgic cpu and dist addresses first\n");
1844                 ret = -ENXIO;
1845                 goto out;
1846         }
1847
1848         ret = kvm_phys_addr_ioremap(kvm, kvm->arch.vgic.vgic_cpu_base,
1849                                     vgic->vcpu_base, KVM_VGIC_V2_CPU_SIZE);
1850         if (ret) {
1851                 kvm_err("Unable to remap VGIC CPU to VCPU\n");
1852                 goto out;
1853         }
1854
1855         for (i = VGIC_NR_PRIVATE_IRQS; i < VGIC_NR_IRQS; i += 4)
1856                 vgic_set_target_reg(kvm, 0, i);
1857
1858         kvm->arch.vgic.ready = true;
1859 out:
1860         mutex_unlock(&kvm->lock);
1861         return ret;
1862 }
1863
1864 int kvm_vgic_create(struct kvm *kvm)
1865 {
1866         int i, vcpu_lock_idx = -1, ret = 0;
1867         struct kvm_vcpu *vcpu;
1868
1869         mutex_lock(&kvm->lock);
1870
1871         if (kvm->arch.vgic.vctrl_base) {
1872                 ret = -EEXIST;
1873                 goto out;
1874         }
1875
1876         /*
1877          * Any time a vcpu is run, vcpu_load is called which tries to grab the
1878          * vcpu->mutex.  By grabbing the vcpu->mutex of all VCPUs we ensure
1879          * that no other VCPUs are run while we create the vgic.
1880          */
1881         kvm_for_each_vcpu(i, vcpu, kvm) {
1882                 if (!mutex_trylock(&vcpu->mutex))
1883                         goto out_unlock;
1884                 vcpu_lock_idx = i;
1885         }
1886
1887         kvm_for_each_vcpu(i, vcpu, kvm) {
1888                 if (vcpu->arch.has_run_once) {
1889                         ret = -EBUSY;
1890                         goto out_unlock;
1891                 }
1892         }
1893
1894         spin_lock_init(&kvm->arch.vgic.lock);
1895         kvm->arch.vgic.in_kernel = true;
1896         kvm->arch.vgic.vctrl_base = vgic->vctrl_base;
1897         kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
1898         kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
1899
1900         ret = vgic_init_maps(kvm);
1901         if (ret)
1902                 kvm_err("Unable to allocate maps\n");
1903
1904 out_unlock:
1905         for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
1906                 vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx);
1907                 mutex_unlock(&vcpu->mutex);
1908         }
1909
1910 out:
1911         mutex_unlock(&kvm->lock);
1912         return ret;
1913 }
1914
1915 static int vgic_ioaddr_overlap(struct kvm *kvm)
1916 {
1917         phys_addr_t dist = kvm->arch.vgic.vgic_dist_base;
1918         phys_addr_t cpu = kvm->arch.vgic.vgic_cpu_base;
1919
1920         if (IS_VGIC_ADDR_UNDEF(dist) || IS_VGIC_ADDR_UNDEF(cpu))
1921                 return 0;
1922         if ((dist <= cpu && dist + KVM_VGIC_V2_DIST_SIZE > cpu) ||
1923             (cpu <= dist && cpu + KVM_VGIC_V2_CPU_SIZE > dist))
1924                 return -EBUSY;
1925         return 0;
1926 }
1927
1928 static int vgic_ioaddr_assign(struct kvm *kvm, phys_addr_t *ioaddr,
1929                               phys_addr_t addr, phys_addr_t size)
1930 {
1931         int ret;
1932
1933         if (addr & ~KVM_PHYS_MASK)
1934                 return -E2BIG;
1935
1936         if (addr & (SZ_4K - 1))
1937                 return -EINVAL;
1938
1939         if (!IS_VGIC_ADDR_UNDEF(*ioaddr))
1940                 return -EEXIST;
1941         if (addr + size < addr)
1942                 return -EINVAL;
1943
1944         *ioaddr = addr;
1945         ret = vgic_ioaddr_overlap(kvm);
1946         if (ret)
1947                 *ioaddr = VGIC_ADDR_UNDEF;
1948
1949         return ret;
1950 }
1951
1952 /**
1953  * kvm_vgic_addr - set or get vgic VM base addresses
1954  * @kvm:   pointer to the vm struct
1955  * @type:  the VGIC addr type, one of KVM_VGIC_V2_ADDR_TYPE_XXX
1956  * @addr:  pointer to address value
1957  * @write: if true set the address in the VM address space, if false read the
1958  *          address
1959  *
1960  * Set or get the vgic base addresses for the distributor and the virtual CPU
1961  * interface in the VM physical address space.  These addresses are properties
1962  * of the emulated core/SoC and therefore user space initially knows this
1963  * information.
1964  */
1965 int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
1966 {
1967         int r = 0;
1968         struct vgic_dist *vgic = &kvm->arch.vgic;
1969
1970         mutex_lock(&kvm->lock);
1971         switch (type) {
1972         case KVM_VGIC_V2_ADDR_TYPE_DIST:
1973                 if (write) {
1974                         r = vgic_ioaddr_assign(kvm, &vgic->vgic_dist_base,
1975                                                *addr, KVM_VGIC_V2_DIST_SIZE);
1976                 } else {
1977                         *addr = vgic->vgic_dist_base;
1978                 }
1979                 break;
1980         case KVM_VGIC_V2_ADDR_TYPE_CPU:
1981                 if (write) {
1982                         r = vgic_ioaddr_assign(kvm, &vgic->vgic_cpu_base,
1983                                                *addr, KVM_VGIC_V2_CPU_SIZE);
1984                 } else {
1985                         *addr = vgic->vgic_cpu_base;
1986                 }
1987                 break;
1988         default:
1989                 r = -ENODEV;
1990         }
1991
1992         mutex_unlock(&kvm->lock);
1993         return r;
1994 }
1995
1996 static bool handle_cpu_mmio_misc(struct kvm_vcpu *vcpu,
1997                                  struct kvm_exit_mmio *mmio, phys_addr_t offset)
1998 {
1999         bool updated = false;
2000         struct vgic_vmcr vmcr;
2001         u32 *vmcr_field;
2002         u32 reg;
2003
2004         vgic_get_vmcr(vcpu, &vmcr);
2005
2006         switch (offset & ~0x3) {
2007         case GIC_CPU_CTRL:
2008                 vmcr_field = &vmcr.ctlr;
2009                 break;
2010         case GIC_CPU_PRIMASK:
2011                 vmcr_field = &vmcr.pmr;
2012                 break;
2013         case GIC_CPU_BINPOINT:
2014                 vmcr_field = &vmcr.bpr;
2015                 break;
2016         case GIC_CPU_ALIAS_BINPOINT:
2017                 vmcr_field = &vmcr.abpr;
2018                 break;
2019         default:
2020                 BUG();
2021         }
2022
2023         if (!mmio->is_write) {
2024                 reg = *vmcr_field;
2025                 mmio_data_write(mmio, ~0, reg);
2026         } else {
2027                 reg = mmio_data_read(mmio, ~0);
2028                 if (reg != *vmcr_field) {
2029                         *vmcr_field = reg;
2030                         vgic_set_vmcr(vcpu, &vmcr);
2031                         updated = true;
2032                 }
2033         }
2034         return updated;
2035 }
2036
2037 static bool handle_mmio_abpr(struct kvm_vcpu *vcpu,
2038                              struct kvm_exit_mmio *mmio, phys_addr_t offset)
2039 {
2040         return handle_cpu_mmio_misc(vcpu, mmio, GIC_CPU_ALIAS_BINPOINT);
2041 }
2042
2043 static bool handle_cpu_mmio_ident(struct kvm_vcpu *vcpu,
2044                                   struct kvm_exit_mmio *mmio,
2045                                   phys_addr_t offset)
2046 {
2047         u32 reg;
2048
2049         if (mmio->is_write)
2050                 return false;
2051
2052         /* GICC_IIDR */
2053         reg = (PRODUCT_ID_KVM << 20) |
2054               (GICC_ARCH_VERSION_V2 << 16) |
2055               (IMPLEMENTER_ARM << 0);
2056         mmio_data_write(mmio, ~0, reg);
2057         return false;
2058 }
2059
2060 /*
2061  * CPU Interface Register accesses - these are not accessed by the VM, but by
2062  * user space for saving and restoring VGIC state.
2063  */
2064 static const struct mmio_range vgic_cpu_ranges[] = {
2065         {
2066                 .base           = GIC_CPU_CTRL,
2067                 .len            = 12,
2068                 .handle_mmio    = handle_cpu_mmio_misc,
2069         },
2070         {
2071                 .base           = GIC_CPU_ALIAS_BINPOINT,
2072                 .len            = 4,
2073                 .handle_mmio    = handle_mmio_abpr,
2074         },
2075         {
2076                 .base           = GIC_CPU_ACTIVEPRIO,
2077                 .len            = 16,
2078                 .handle_mmio    = handle_mmio_raz_wi,
2079         },
2080         {
2081                 .base           = GIC_CPU_IDENT,
2082                 .len            = 4,
2083                 .handle_mmio    = handle_cpu_mmio_ident,
2084         },
2085 };
2086
2087 static int vgic_attr_regs_access(struct kvm_device *dev,
2088                                  struct kvm_device_attr *attr,
2089                                  u32 *reg, bool is_write)
2090 {
2091         const struct mmio_range *r = NULL, *ranges;
2092         phys_addr_t offset;
2093         int ret, cpuid, c;
2094         struct kvm_vcpu *vcpu, *tmp_vcpu;
2095         struct vgic_dist *vgic;
2096         struct kvm_exit_mmio mmio;
2097
2098         offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
2099         cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >>
2100                 KVM_DEV_ARM_VGIC_CPUID_SHIFT;
2101
2102         mutex_lock(&dev->kvm->lock);
2103
2104         if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) {
2105                 ret = -EINVAL;
2106                 goto out;
2107         }
2108
2109         vcpu = kvm_get_vcpu(dev->kvm, cpuid);
2110         vgic = &dev->kvm->arch.vgic;
2111
2112         mmio.len = 4;
2113         mmio.is_write = is_write;
2114         if (is_write)
2115                 mmio_data_write(&mmio, ~0, *reg);
2116         switch (attr->group) {
2117         case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
2118                 mmio.phys_addr = vgic->vgic_dist_base + offset;
2119                 ranges = vgic_dist_ranges;
2120                 break;
2121         case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
2122                 mmio.phys_addr = vgic->vgic_cpu_base + offset;
2123                 ranges = vgic_cpu_ranges;
2124                 break;
2125         default:
2126                 BUG();
2127         }
2128         r = find_matching_range(ranges, &mmio, offset);
2129
2130         if (unlikely(!r || !r->handle_mmio)) {
2131                 ret = -ENXIO;
2132                 goto out;
2133         }
2134
2135
2136         spin_lock(&vgic->lock);
2137
2138         /*
2139          * Ensure that no other VCPU is running by checking the vcpu->cpu
2140          * field.  If no other VPCUs are running we can safely access the VGIC
2141          * state, because even if another VPU is run after this point, that
2142          * VCPU will not touch the vgic state, because it will block on
2143          * getting the vgic->lock in kvm_vgic_sync_hwstate().
2144          */
2145         kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) {
2146                 if (unlikely(tmp_vcpu->cpu != -1)) {
2147                         ret = -EBUSY;
2148                         goto out_vgic_unlock;
2149                 }
2150         }
2151
2152         /*
2153          * Move all pending IRQs from the LRs on all VCPUs so the pending
2154          * state can be properly represented in the register state accessible
2155          * through this API.
2156          */
2157         kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm)
2158                 vgic_unqueue_irqs(tmp_vcpu);
2159
2160         offset -= r->base;
2161         r->handle_mmio(vcpu, &mmio, offset);
2162
2163         if (!is_write)
2164                 *reg = mmio_data_read(&mmio, ~0);
2165
2166         ret = 0;
2167 out_vgic_unlock:
2168         spin_unlock(&vgic->lock);
2169 out:
2170         mutex_unlock(&dev->kvm->lock);
2171         return ret;
2172 }
2173
2174 static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
2175 {
2176         int r;
2177
2178         switch (attr->group) {
2179         case KVM_DEV_ARM_VGIC_GRP_ADDR: {
2180                 u64 __user *uaddr = (u64 __user *)(long)attr->addr;
2181                 u64 addr;
2182                 unsigned long type = (unsigned long)attr->attr;
2183
2184                 if (copy_from_user(&addr, uaddr, sizeof(addr)))
2185                         return -EFAULT;
2186
2187                 r = kvm_vgic_addr(dev->kvm, type, &addr, true);
2188                 return (r == -ENODEV) ? -ENXIO : r;
2189         }
2190
2191         case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
2192         case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
2193                 u32 __user *uaddr = (u32 __user *)(long)attr->addr;
2194                 u32 reg;
2195
2196                 if (get_user(reg, uaddr))
2197                         return -EFAULT;
2198
2199                 return vgic_attr_regs_access(dev, attr, &reg, true);
2200         }
2201
2202         }
2203
2204         return -ENXIO;
2205 }
2206
2207 static int vgic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
2208 {
2209         int r = -ENXIO;
2210
2211         switch (attr->group) {
2212         case KVM_DEV_ARM_VGIC_GRP_ADDR: {
2213                 u64 __user *uaddr = (u64 __user *)(long)attr->addr;
2214                 u64 addr;
2215                 unsigned long type = (unsigned long)attr->attr;
2216
2217                 r = kvm_vgic_addr(dev->kvm, type, &addr, false);
2218                 if (r)
2219                         return (r == -ENODEV) ? -ENXIO : r;
2220
2221                 if (copy_to_user(uaddr, &addr, sizeof(addr)))
2222                         return -EFAULT;
2223                 break;
2224         }
2225
2226         case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
2227         case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: {
2228                 u32 __user *uaddr = (u32 __user *)(long)attr->addr;
2229                 u32 reg = 0;
2230
2231                 r = vgic_attr_regs_access(dev, attr, &reg, false);
2232                 if (r)
2233                         return r;
2234                 r = put_user(reg, uaddr);
2235                 break;
2236         }
2237
2238         }
2239
2240         return r;
2241 }
2242
2243 static int vgic_has_attr_regs(const struct mmio_range *ranges,
2244                               phys_addr_t offset)
2245 {
2246         struct kvm_exit_mmio dev_attr_mmio;
2247
2248         dev_attr_mmio.len = 4;
2249         if (find_matching_range(ranges, &dev_attr_mmio, offset))
2250                 return 0;
2251         else
2252                 return -ENXIO;
2253 }
2254
2255 static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
2256 {
2257         phys_addr_t offset;
2258
2259         switch (attr->group) {
2260         case KVM_DEV_ARM_VGIC_GRP_ADDR:
2261                 switch (attr->attr) {
2262                 case KVM_VGIC_V2_ADDR_TYPE_DIST:
2263                 case KVM_VGIC_V2_ADDR_TYPE_CPU:
2264                         return 0;
2265                 }
2266                 break;
2267         case KVM_DEV_ARM_VGIC_GRP_DIST_REGS:
2268                 offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
2269                 return vgic_has_attr_regs(vgic_dist_ranges, offset);
2270         case KVM_DEV_ARM_VGIC_GRP_CPU_REGS:
2271                 offset = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK;
2272                 return vgic_has_attr_regs(vgic_cpu_ranges, offset);
2273         }
2274         return -ENXIO;
2275 }
2276
2277 static void vgic_destroy(struct kvm_device *dev)
2278 {
2279         kfree(dev);
2280 }
2281
2282 static int vgic_create(struct kvm_device *dev, u32 type)
2283 {
2284         return kvm_vgic_create(dev->kvm);
2285 }
2286
2287 static struct kvm_device_ops kvm_arm_vgic_v2_ops = {
2288         .name = "kvm-arm-vgic",
2289         .create = vgic_create,
2290         .destroy = vgic_destroy,
2291         .set_attr = vgic_set_attr,
2292         .get_attr = vgic_get_attr,
2293         .has_attr = vgic_has_attr,
2294 };
2295
2296 static void vgic_init_maintenance_interrupt(void *info)
2297 {
2298         enable_percpu_irq(vgic->maint_irq, 0);
2299 }
2300
2301 static int vgic_cpu_notify(struct notifier_block *self,
2302                            unsigned long action, void *cpu)
2303 {
2304         switch (action) {
2305         case CPU_STARTING:
2306         case CPU_STARTING_FROZEN:
2307                 vgic_init_maintenance_interrupt(NULL);
2308                 break;
2309         case CPU_DYING:
2310         case CPU_DYING_FROZEN:
2311                 disable_percpu_irq(vgic->maint_irq);
2312                 break;
2313         }
2314
2315         return NOTIFY_OK;
2316 }
2317
2318 static struct notifier_block vgic_cpu_nb = {
2319         .notifier_call = vgic_cpu_notify,
2320 };
2321
2322 static const struct of_device_id vgic_ids[] = {
2323         { .compatible = "arm,cortex-a15-gic", .data = vgic_v2_probe, },
2324         { .compatible = "arm,gic-v3", .data = vgic_v3_probe, },
2325         {},
2326 };
2327
2328 int kvm_vgic_hyp_init(void)
2329 {
2330         const struct of_device_id *matched_id;
2331         int (*vgic_probe)(struct device_node *,const struct vgic_ops **,
2332                           const struct vgic_params **);
2333         struct device_node *vgic_node;
2334         int ret;
2335
2336         vgic_node = of_find_matching_node_and_match(NULL,
2337                                                     vgic_ids, &matched_id);
2338         if (!vgic_node) {
2339                 kvm_err("error: no compatible GIC node found\n");
2340                 return -ENODEV;
2341         }
2342
2343         vgic_probe = matched_id->data;
2344         ret = vgic_probe(vgic_node, &vgic_ops, &vgic);
2345         if (ret)
2346                 return ret;
2347
2348         ret = request_percpu_irq(vgic->maint_irq, vgic_maintenance_handler,
2349                                  "vgic", kvm_get_running_vcpus());
2350         if (ret) {
2351                 kvm_err("Cannot register interrupt %d\n", vgic->maint_irq);
2352                 return ret;
2353         }
2354
2355         ret = __register_cpu_notifier(&vgic_cpu_nb);
2356         if (ret) {
2357                 kvm_err("Cannot register vgic CPU notifier\n");
2358                 goto out_free_irq;
2359         }
2360
2361         /* Callback into for arch code for setup */
2362         vgic_arch_setup(vgic);
2363
2364         on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
2365
2366         return kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
2367                                        KVM_DEV_TYPE_ARM_VGIC_V2);
2368
2369 out_free_irq:
2370         free_percpu_irq(vgic->maint_irq, kvm_get_running_vcpus());
2371         return ret;
2372 }