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