virt/kvm/arm/vgic/vgic-its.c

   1 /*
   2  * GICv3 ITS emulation
   3  *
   4  * Copyright (C) 2015,2016 ARM Ltd.
   5  * Author: Andre Przywara <andre.przywara@arm.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <linux/cpu.h>
  21 #include <linux/kvm.h>
  22 #include <linux/kvm_host.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/list.h>
  25 #include <linux/uaccess.h>
  26
  27 #include <linux/irqchip/arm-gic-v3.h>
  28
  29 #include <asm/kvm_emulate.h>
  30 #include <asm/kvm_arm.h>
  31 #include <asm/kvm_mmu.h>
  32
  33 #include "vgic.h"
  34 #include "vgic-mmio.h"
  35
  36 /*
  37  * Creates a new (reference to a) struct vgic_irq for a given LPI.
  38  * If this LPI is already mapped on another ITS, we increase its refcount
  39  * and return a pointer to the existing structure.
  40  * If this is a "new" LPI, we allocate and initialize a new struct vgic_irq.
  41  * This function returns a pointer to the _unlocked_ structure.
  42  */
  43 static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid)
  44 {
  45         struct vgic_dist *dist = &kvm->arch.vgic;
  46         struct vgic_irq *irq = vgic_get_irq(kvm, NULL, intid), *oldirq;
  47
  48         /* In this case there is no put, since we keep the reference. */
  49         if (irq)
  50                 return irq;
  51
  52         irq = kzalloc(sizeof(struct vgic_irq), GFP_KERNEL);
  53         if (!irq)
  54                 return ERR_PTR(-ENOMEM);
  55
  56         INIT_LIST_HEAD(&irq->lpi_list);
  57         INIT_LIST_HEAD(&irq->ap_list);
  58         spin_lock_init(&irq->irq_lock);
  59
  60         irq->config = VGIC_CONFIG_EDGE;
  61         kref_init(&irq->refcount);
  62         irq->intid = intid;
  63
  64         spin_lock(&dist->lpi_list_lock);
  65
  66         /*
  67          * There could be a race with another vgic_add_lpi(), so we need to
  68          * check that we don't add a second list entry with the same LPI.
  69          */
  70         list_for_each_entry(oldirq, &dist->lpi_list_head, lpi_list) {
  71                 if (oldirq->intid != intid)
  72                         continue;
  73
  74                 /* Someone was faster with adding this LPI, lets use that. */
  75                 kfree(irq);
  76                 irq = oldirq;
  77
  78                 /*
  79                  * This increases the refcount, the caller is expected to
  80                  * call vgic_put_irq() on the returned pointer once it's
  81                  * finished with the IRQ.
  82                  */
  83                 vgic_get_irq_kref(irq);
  84
  85                 goto out_unlock;
  86         }
  87
  88         list_add_tail(&irq->lpi_list, &dist->lpi_list_head);
  89         dist->lpi_list_count++;
  90
  91 out_unlock:
  92         spin_unlock(&dist->lpi_list_lock);
  93
  94         return irq;
  95 }
  96
  97 struct its_device {
  98         struct list_head dev_list;
  99
 100         /* the head for the list of ITTEs */
 101         struct list_head itt_head;
 102         u32 device_id;
 103 };
 104
 105 #define COLLECTION_NOT_MAPPED ((u32)~0)
 106
 107 struct its_collection {
 108         struct list_head coll_list;
 109
 110         u32 collection_id;
 111         u32 target_addr;
 112 };
 113
 114 #define its_is_collection_mapped(coll) ((coll) && \
 115                                 ((coll)->target_addr != COLLECTION_NOT_MAPPED))
 116
 117 struct its_itte {
 118         struct list_head itte_list;
 119
 120         struct vgic_irq *irq;
 121         struct its_collection *collection;
 122         u32 lpi;
 123         u32 event_id;
 124 };
 125
 126 /*
 127  * Find and returns a device in the device table for an ITS.
 128  * Must be called with the its_lock mutex held.
 129  */
 130 static struct its_device *find_its_device(struct vgic_its *its, u32 device_id)
 131 {
 132         struct its_device *device;
 133
 134         list_for_each_entry(device, &its->device_list, dev_list)
 135                 if (device_id == device->device_id)
 136                         return device;
 137
 138         return NULL;
 139 }
 140
 141 /*
 142  * Find and returns an interrupt translation table entry (ITTE) for a given
 143  * Device ID/Event ID pair on an ITS.
 144  * Must be called with the its_lock mutex held.
 145  */
 146 static struct its_itte *find_itte(struct vgic_its *its, u32 device_id,
 147                                   u32 event_id)
 148 {
 149         struct its_device *device;
 150         struct its_itte *itte;
 151
 152         device = find_its_device(its, device_id);
 153         if (device == NULL)
 154                 return NULL;
 155
 156         list_for_each_entry(itte, &device->itt_head, itte_list)
 157                 if (itte->event_id == event_id)
 158                         return itte;
 159
 160         return NULL;
 161 }
 162
 163 /* To be used as an iterator this macro misses the enclosing parentheses */
 164 #define for_each_lpi_its(dev, itte, its) \
 165         list_for_each_entry(dev, &(its)->device_list, dev_list) \
 166                 list_for_each_entry(itte, &(dev)->itt_head, itte_list)
 167
 168 /*
 169  * We only implement 48 bits of PA at the moment, although the ITS
 170  * supports more. Let's be restrictive here.
 171  */
 172 #define BASER_ADDRESS(x)        ((x) & GENMASK_ULL(47, 16))
 173 #define CBASER_ADDRESS(x)       ((x) & GENMASK_ULL(47, 12))
 174 #define PENDBASER_ADDRESS(x)    ((x) & GENMASK_ULL(47, 16))
 175 #define PROPBASER_ADDRESS(x)    ((x) & GENMASK_ULL(47, 12))
 176
 177 #define GIC_LPI_OFFSET 8192
 178
 179 /*
 180  * Finds and returns a collection in the ITS collection table.
 181  * Must be called with the its_lock mutex held.
 182  */
 183 static struct its_collection *find_collection(struct vgic_its *its, int coll_id)
 184 {
 185         struct its_collection *collection;
 186
 187         list_for_each_entry(collection, &its->collection_list, coll_list) {
 188                 if (coll_id == collection->collection_id)
 189                         return collection;
 190         }
 191
 192         return NULL;
 193 }
 194
 195 #define LPI_PROP_ENABLE_BIT(p)  ((p) & LPI_PROP_ENABLED)
 196 #define LPI_PROP_PRIORITY(p)    ((p) & 0xfc)
 197
 198 /*
 199  * Reads the configuration data for a given LPI from guest memory and
 200  * updates the fields in struct vgic_irq.
 201  * If filter_vcpu is not NULL, applies only if the IRQ is targeting this
 202  * VCPU. Unconditionally applies if filter_vcpu is NULL.
 203  */
 204 static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
 205                              struct kvm_vcpu *filter_vcpu)
 206 {
 207         u64 propbase = PROPBASER_ADDRESS(kvm->arch.vgic.propbaser);
 208         u8 prop;
 209         int ret;
 210
 211         ret = kvm_read_guest(kvm, propbase + irq->intid - GIC_LPI_OFFSET,
 212                              &prop, 1);
 213
 214         if (ret)
 215                 return ret;
 216
 217         spin_lock(&irq->irq_lock);
 218
 219         if (!filter_vcpu || filter_vcpu == irq->target_vcpu) {
 220                 irq->priority = LPI_PROP_PRIORITY(prop);
 221                 irq->enabled = LPI_PROP_ENABLE_BIT(prop);
 222
 223                 vgic_queue_irq_unlock(kvm, irq);
 224         } else {
 225                 spin_unlock(&irq->irq_lock);
 226         }
 227
 228         return 0;
 229 }
 230
 231 /*
 232  * Create a snapshot of the current LPI list, so that we can enumerate all
 233  * LPIs without holding any lock.
 234  * Returns the array length and puts the kmalloc'ed array into intid_ptr.
 235  */
 236 static int vgic_copy_lpi_list(struct kvm *kvm, u32 **intid_ptr)
 237 {
 238         struct vgic_dist *dist = &kvm->arch.vgic;
 239         struct vgic_irq *irq;
 240         u32 *intids;
 241         int irq_count = dist->lpi_list_count, i = 0;
 242
 243         /*
 244          * We use the current value of the list length, which may change
 245          * after the kmalloc. We don't care, because the guest shouldn't
 246          * change anything while the command handling is still running,
 247          * and in the worst case we would miss a new IRQ, which one wouldn't
 248          * expect to be covered by this command anyway.
 249          */
 250         intids = kmalloc_array(irq_count, sizeof(intids[0]), GFP_KERNEL);
 251         if (!intids)
 252                 return -ENOMEM;
 253
 254         spin_lock(&dist->lpi_list_lock);
 255         list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
 256                 /* We don't need to "get" the IRQ, as we hold the list lock. */
 257                 intids[i] = irq->intid;
 258                 if (++i == irq_count)
 259                         break;
 260         }
 261         spin_unlock(&dist->lpi_list_lock);
 262
 263         *intid_ptr = intids;
 264         return irq_count;
 265 }
 266
 267 /*
 268  * Promotes the ITS view of affinity of an ITTE (which redistributor this LPI
 269  * is targeting) to the VGIC's view, which deals with target VCPUs.
 270  * Needs to be called whenever either the collection for a LPIs has
 271  * changed or the collection itself got retargeted.
 272  */
 273 static void update_affinity_itte(struct kvm *kvm, struct its_itte *itte)
 274 {
 275         struct kvm_vcpu *vcpu;
 276
 277         if (!its_is_collection_mapped(itte->collection))
 278                 return;
 279
 280         vcpu = kvm_get_vcpu(kvm, itte->collection->target_addr);
 281
 282         spin_lock(&itte->irq->irq_lock);
 283         itte->irq->target_vcpu = vcpu;
 284         spin_unlock(&itte->irq->irq_lock);
 285 }
 286
 287 /*
 288  * Updates the target VCPU for every LPI targeting this collection.
 289  * Must be called with the its_lock mutex held.
 290  */
 291 static void update_affinity_collection(struct kvm *kvm, struct vgic_its *its,
 292                                        struct its_collection *coll)
 293 {
 294         struct its_device *device;
 295         struct its_itte *itte;
 296
 297         for_each_lpi_its(device, itte, its) {
 298                 if (!itte->collection || coll != itte->collection)
 299                         continue;
 300
 301                 update_affinity_itte(kvm, itte);
 302         }
 303 }
 304
 305 static u32 max_lpis_propbaser(u64 propbaser)
 306 {
 307         int nr_idbits = (propbaser & 0x1f) + 1;
 308
 309         return 1U << min(nr_idbits, INTERRUPT_ID_BITS_ITS);
 310 }
 311
 312 /*
 313  * Scan the whole LPI pending table and sync the pending bit in there
 314  * with our own data structures. This relies on the LPI being
 315  * mapped before.
 316  */
 317 static int its_sync_lpi_pending_table(struct kvm_vcpu *vcpu)
 318 {
 319         gpa_t pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
 320         struct vgic_irq *irq;
 321         int last_byte_offset = -1;
 322         int ret = 0;
 323         u32 *intids;
 324         int nr_irqs, i;
 325
 326         nr_irqs = vgic_copy_lpi_list(vcpu->kvm, &intids);
 327         if (nr_irqs < 0)
 328                 return nr_irqs;
 329
 330         for (i = 0; i < nr_irqs; i++) {
 331                 int byte_offset, bit_nr;
 332                 u8 pendmask;
 333
 334                 byte_offset = intids[i] / BITS_PER_BYTE;
 335                 bit_nr = intids[i] % BITS_PER_BYTE;
 336
 337                 /*
 338                  * For contiguously allocated LPIs chances are we just read
 339                  * this very same byte in the last iteration. Reuse that.
 340                  */
 341                 if (byte_offset != last_byte_offset) {
 342                         ret = kvm_read_guest(vcpu->kvm, pendbase + byte_offset,
 343                                              &pendmask, 1);
 344                         if (ret) {
 345                                 kfree(intids);
 346                                 return ret;
 347                         }
 348                         last_byte_offset = byte_offset;
 349                 }
 350
 351                 irq = vgic_get_irq(vcpu->kvm, NULL, intids[i]);
 352                 spin_lock(&irq->irq_lock);
 353                 irq->pending = pendmask & (1U << bit_nr);
 354                 vgic_queue_irq_unlock(vcpu->kvm, irq);
 355                 vgic_put_irq(vcpu->kvm, irq);
 356         }
 357
 358         kfree(intids);
 359
 360         return ret;
 361 }
 362
 363 static unsigned long vgic_mmio_read_its_ctlr(struct kvm *vcpu,
 364                                              struct vgic_its *its,
 365                                              gpa_t addr, unsigned int len)
 366 {
 367         u32 reg = 0;
 368
 369         mutex_lock(&its->cmd_lock);
 370         if (its->creadr == its->cwriter)
 371                 reg |= GITS_CTLR_QUIESCENT;
 372         if (its->enabled)
 373                 reg |= GITS_CTLR_ENABLE;
 374         mutex_unlock(&its->cmd_lock);
 375
 376         return reg;
 377 }
 378
 379 static void vgic_mmio_write_its_ctlr(struct kvm *kvm, struct vgic_its *its,
 380                                      gpa_t addr, unsigned int len,
 381                                      unsigned long val)
 382 {
 383         its->enabled = !!(val & GITS_CTLR_ENABLE);
 384 }
 385
 386 static unsigned long vgic_mmio_read_its_typer(struct kvm *kvm,
 387                                               struct vgic_its *its,
 388                                               gpa_t addr, unsigned int len)
 389 {
 390         u64 reg = GITS_TYPER_PLPIS;
 391
 392         /*
 393          * We use linear CPU numbers for redistributor addressing,
 394          * so GITS_TYPER.PTA is 0.
 395          * Also we force all PROPBASER registers to be the same, so
 396          * CommonLPIAff is 0 as well.
 397          * To avoid memory waste in the guest, we keep the number of IDBits and
 398          * DevBits low - as least for the time being.
 399          */
 400         reg |= 0x0f << GITS_TYPER_DEVBITS_SHIFT;
 401         reg |= 0x0f << GITS_TYPER_IDBITS_SHIFT;
 402
 403         return extract_bytes(reg, addr & 7, len);
 404 }
 405
 406 static unsigned long vgic_mmio_read_its_iidr(struct kvm *kvm,
 407                                              struct vgic_its *its,
 408                                              gpa_t addr, unsigned int len)
 409 {
 410         return (PRODUCT_ID_KVM << 24) | (IMPLEMENTER_ARM << 0);
 411 }
 412
 413 static unsigned long vgic_mmio_read_its_idregs(struct kvm *kvm,
 414                                                struct vgic_its *its,
 415                                                gpa_t addr, unsigned int len)
 416 {
 417         switch (addr & 0xffff) {
 418         case GITS_PIDR0:
 419                 return 0x92;    /* part number, bits[7:0] */
 420         case GITS_PIDR1:
 421                 return 0xb4;    /* part number, bits[11:8] */
 422         case GITS_PIDR2:
 423                 return GIC_PIDR2_ARCH_GICv3 | 0x0b;
 424         case GITS_PIDR4:
 425                 return 0x40;    /* This is a 64K software visible page */
 426         /* The following are the ID registers for (any) GIC. */
 427         case GITS_CIDR0:
 428                 return 0x0d;
 429         case GITS_CIDR1:
 430                 return 0xf0;
 431         case GITS_CIDR2:
 432                 return 0x05;
 433         case GITS_CIDR3:
 434                 return 0xb1;
 435         }
 436
 437         return 0;
 438 }
 439
 440 /*
 441  * Find the target VCPU and the LPI number for a given devid/eventid pair
 442  * and make this IRQ pending, possibly injecting it.
 443  * Must be called with the its_lock mutex held.
 444  * Returns 0 on success, a positive error value for any ITS mapping
 445  * related errors and negative error values for generic errors.
 446  */
 447 static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
 448                                 u32 devid, u32 eventid)
 449 {
 450         struct kvm_vcpu *vcpu;
 451         struct its_itte *itte;
 452
 453         if (!its->enabled)
 454                 return -EBUSY;
 455
 456         itte = find_itte(its, devid, eventid);
 457         if (!itte || !its_is_collection_mapped(itte->collection))
 458                 return E_ITS_INT_UNMAPPED_INTERRUPT;
 459
 460         vcpu = kvm_get_vcpu(kvm, itte->collection->target_addr);
 461         if (!vcpu)
 462                 return E_ITS_INT_UNMAPPED_INTERRUPT;
 463
 464         if (!vcpu->arch.vgic_cpu.lpis_enabled)
 465                 return -EBUSY;
 466
 467         spin_lock(&itte->irq->irq_lock);
 468         itte->irq->pending = true;
 469         vgic_queue_irq_unlock(kvm, itte->irq);
 470
 471         return 0;
 472 }
 473
 474 static struct vgic_io_device *vgic_get_its_iodev(struct kvm_io_device *dev)
 475 {
 476         struct vgic_io_device *iodev;
 477
 478         if (dev->ops != &kvm_io_gic_ops)
 479                 return NULL;
 480
 481         iodev = container_of(dev, struct vgic_io_device, dev);
 482
 483         if (iodev->iodev_type != IODEV_ITS)
 484                 return NULL;
 485
 486         return iodev;
 487 }
 488
 489 /*
 490  * Queries the KVM IO bus framework to get the ITS pointer from the given
 491  * doorbell address.
 492  * We then call vgic_its_trigger_msi() with the decoded data.
 493  * According to the KVM_SIGNAL_MSI API description returns 1 on success.
 494  */
 495 int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
 496 {
 497         u64 address;
 498         struct kvm_io_device *kvm_io_dev;
 499         struct vgic_io_device *iodev;
 500         int ret;
 501
 502         if (!vgic_has_its(kvm))
 503                 return -ENODEV;
 504
 505         if (!(msi->flags & KVM_MSI_VALID_DEVID))
 506                 return -EINVAL;
 507
 508         address = (u64)msi->address_hi << 32 | msi->address_lo;
 509
 510         kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address);
 511         if (!kvm_io_dev)
 512                 return -EINVAL;
 513
 514         iodev = vgic_get_its_iodev(kvm_io_dev);
 515         if (!iodev)
 516                 return -EINVAL;
 517
 518         mutex_lock(&iodev->its->its_lock);
 519         ret = vgic_its_trigger_msi(kvm, iodev->its, msi->devid, msi->data);
 520         mutex_unlock(&iodev->its->its_lock);
 521
 522         if (ret < 0)
 523                 return ret;
 524
 525         /*
 526          * KVM_SIGNAL_MSI demands a return value > 0 for success and 0
 527          * if the guest has blocked the MSI. So we map any LPI mapping
 528          * related error to that.
 529          */
 530         if (ret)
 531                 return 0;
 532         else
 533                 return 1;
 534 }
 535
 536 /* Requires the its_lock to be held. */
 537 static void its_free_itte(struct kvm *kvm, struct its_itte *itte)
 538 {
 539         list_del(&itte->itte_list);
 540
 541         /* This put matches the get in vgic_add_lpi. */
 542         if (itte->irq)
 543                 vgic_put_irq(kvm, itte->irq);
 544
 545         kfree(itte);
 546 }
 547
 548 static u64 its_cmd_mask_field(u64 *its_cmd, int word, int shift, int size)
 549 {
 550         return (le64_to_cpu(its_cmd[word]) >> shift) & (BIT_ULL(size) - 1);
 551 }
 552
 553 #define its_cmd_get_command(cmd)        its_cmd_mask_field(cmd, 0,  0,  8)
 554 #define its_cmd_get_deviceid(cmd)       its_cmd_mask_field(cmd, 0, 32, 32)
 555 #define its_cmd_get_id(cmd)             its_cmd_mask_field(cmd, 1,  0, 32)
 556 #define its_cmd_get_physical_id(cmd)    its_cmd_mask_field(cmd, 1, 32, 32)
 557 #define its_cmd_get_collection(cmd)     its_cmd_mask_field(cmd, 2,  0, 16)
 558 #define its_cmd_get_target_addr(cmd)    its_cmd_mask_field(cmd, 2, 16, 32)
 559 #define its_cmd_get_validbit(cmd)       its_cmd_mask_field(cmd, 2, 63,  1)
 560
 561 /*
 562  * The DISCARD command frees an Interrupt Translation Table Entry (ITTE).
 563  * Must be called with the its_lock mutex held.
 564  */
 565 static int vgic_its_cmd_handle_discard(struct kvm *kvm, struct vgic_its *its,
 566                                        u64 *its_cmd)
 567 {
 568         u32 device_id = its_cmd_get_deviceid(its_cmd);
 569         u32 event_id = its_cmd_get_id(its_cmd);
 570         struct its_itte *itte;
 571
 572
 573         itte = find_itte(its, device_id, event_id);
 574         if (itte && itte->collection) {
 575                 /*
 576                  * Though the spec talks about removing the pending state, we
 577                  * don't bother here since we clear the ITTE anyway and the
 578                  * pending state is a property of the ITTE struct.
 579                  */
 580                 its_free_itte(kvm, itte);
 581                 return 0;
 582         }
 583
 584         return E_ITS_DISCARD_UNMAPPED_INTERRUPT;
 585 }
 586
 587 /*
 588  * The MOVI command moves an ITTE to a different collection.
 589  * Must be called with the its_lock mutex held.
 590  */
 591 static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its,
 592                                     u64 *its_cmd)
 593 {
 594         u32 device_id = its_cmd_get_deviceid(its_cmd);
 595         u32 event_id = its_cmd_get_id(its_cmd);
 596         u32 coll_id = its_cmd_get_collection(its_cmd);
 597         struct kvm_vcpu *vcpu;
 598         struct its_itte *itte;
 599         struct its_collection *collection;
 600
 601         itte = find_itte(its, device_id, event_id);
 602         if (!itte)
 603                 return E_ITS_MOVI_UNMAPPED_INTERRUPT;
 604
 605         if (!its_is_collection_mapped(itte->collection))
 606                 return E_ITS_MOVI_UNMAPPED_COLLECTION;
 607
 608         collection = find_collection(its, coll_id);
 609         if (!its_is_collection_mapped(collection))
 610                 return E_ITS_MOVI_UNMAPPED_COLLECTION;
 611
 612         itte->collection = collection;
 613         vcpu = kvm_get_vcpu(kvm, collection->target_addr);
 614
 615         spin_lock(&itte->irq->irq_lock);
 616         itte->irq->target_vcpu = vcpu;
 617         spin_unlock(&itte->irq->irq_lock);
 618
 619         return 0;
 620 }
 621
 622 /*
 623  * Check whether an ID can be stored into the corresponding guest table.
 624  * For a direct table this is pretty easy, but gets a bit nasty for
 625  * indirect tables. We check whether the resulting guest physical address
 626  * is actually valid (covered by a memslot and guest accessbible).
 627  * For this we have to read the respective first level entry.
 628  */
 629 static bool vgic_its_check_id(struct vgic_its *its, u64 baser, int id)
 630 {
 631         int l1_tbl_size = GITS_BASER_NR_PAGES(baser) * SZ_64K;
 632         int index;
 633         u64 indirect_ptr;
 634         gfn_t gfn;
 635
 636         if (!(baser & GITS_BASER_INDIRECT)) {
 637                 phys_addr_t addr;
 638
 639                 if (id >= (l1_tbl_size / GITS_BASER_ENTRY_SIZE(baser)))
 640                         return false;
 641
 642                 addr = BASER_ADDRESS(baser) + id * GITS_BASER_ENTRY_SIZE(baser);
 643                 gfn = addr >> PAGE_SHIFT;
 644
 645                 return kvm_is_visible_gfn(its->dev->kvm, gfn);
 646         }
 647
 648         /* calculate and check the index into the 1st level */
 649         index = id / (SZ_64K / GITS_BASER_ENTRY_SIZE(baser));
 650         if (index >= (l1_tbl_size / sizeof(u64)))
 651                 return false;
 652
 653         /* Each 1st level entry is represented by a 64-bit value. */
 654         if (kvm_read_guest(its->dev->kvm,
 655                            BASER_ADDRESS(baser) + index * sizeof(indirect_ptr),
 656                            &indirect_ptr, sizeof(indirect_ptr)))
 657                 return false;
 658
 659         indirect_ptr = le64_to_cpu(indirect_ptr);
 660
 661         /* check the valid bit of the first level entry */
 662         if (!(indirect_ptr & BIT_ULL(63)))
 663                 return false;
 664
 665         /*
 666          * Mask the guest physical address and calculate the frame number.
 667          * Any address beyond our supported 48 bits of PA will be caught
 668          * by the actual check in the final step.
 669          */
 670         indirect_ptr &= GENMASK_ULL(51, 16);
 671
 672         /* Find the address of the actual entry */
 673         index = id % (SZ_64K / GITS_BASER_ENTRY_SIZE(baser));
 674         indirect_ptr += index * GITS_BASER_ENTRY_SIZE(baser);
 675         gfn = indirect_ptr >> PAGE_SHIFT;
 676
 677         return kvm_is_visible_gfn(its->dev->kvm, gfn);
 678 }
 679
 680 static int vgic_its_alloc_collection(struct vgic_its *its,
 681                                      struct its_collection **colp,
 682                                      u32 coll_id)
 683 {
 684         struct its_collection *collection;
 685
 686         if (!vgic_its_check_id(its, its->baser_coll_table, coll_id))
 687                 return E_ITS_MAPC_COLLECTION_OOR;
 688
 689         collection = kzalloc(sizeof(*collection), GFP_KERNEL);
 690
 691         collection->collection_id = coll_id;
 692         collection->target_addr = COLLECTION_NOT_MAPPED;
 693
 694         list_add_tail(&collection->coll_list, &its->collection_list);
 695         *colp = collection;
 696
 697         return 0;
 698 }
 699
 700 static void vgic_its_free_collection(struct vgic_its *its, u32 coll_id)
 701 {
 702         struct its_collection *collection;
 703         struct its_device *device;
 704         struct its_itte *itte;
 705
 706         /*
 707          * Clearing the mapping for that collection ID removes the
 708          * entry from the list. If there wasn't any before, we can
 709          * go home early.
 710          */
 711         collection = find_collection(its, coll_id);
 712         if (!collection)
 713                 return;
 714
 715         for_each_lpi_its(device, itte, its)
 716                 if (itte->collection &&
 717                     itte->collection->collection_id == coll_id)
 718                         itte->collection = NULL;
 719
 720         list_del(&collection->coll_list);
 721         kfree(collection);
 722 }
 723
 724 /*
 725  * The MAPTI and MAPI commands map LPIs to ITTEs.
 726  * Must be called with its_lock mutex held.
 727  */
 728 static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
 729                                     u64 *its_cmd)
 730 {
 731         u32 device_id = its_cmd_get_deviceid(its_cmd);
 732         u32 event_id = its_cmd_get_id(its_cmd);
 733         u32 coll_id = its_cmd_get_collection(its_cmd);
 734         struct its_itte *itte;
 735         struct its_device *device;
 736         struct its_collection *collection, *new_coll = NULL;
 737         int lpi_nr;
 738         struct vgic_irq *irq;
 739
 740         device = find_its_device(its, device_id);
 741         if (!device)
 742                 return E_ITS_MAPTI_UNMAPPED_DEVICE;
 743
 744         if (its_cmd_get_command(its_cmd) == GITS_CMD_MAPTI)
 745                 lpi_nr = its_cmd_get_physical_id(its_cmd);
 746         else
 747                 lpi_nr = event_id;
 748         if (lpi_nr < GIC_LPI_OFFSET ||
 749             lpi_nr >= max_lpis_propbaser(kvm->arch.vgic.propbaser))
 750                 return E_ITS_MAPTI_PHYSICALID_OOR;
 751
 752         /* If there is an existing mapping, behavior is UNPREDICTABLE. */
 753         if (find_itte(its, device_id, event_id))
 754                 return 0;
 755
 756         collection = find_collection(its, coll_id);
 757         if (!collection) {
 758                 int ret = vgic_its_alloc_collection(its, &collection, coll_id);
 759                 if (ret)
 760                         return ret;
 761                 new_coll = collection;
 762         }
 763
 764         itte = kzalloc(sizeof(struct its_itte), GFP_KERNEL);
 765         if (!itte) {
 766                 if (new_coll)
 767                         vgic_its_free_collection(its, coll_id);
 768                 return -ENOMEM;
 769         }
 770
 771         itte->event_id  = event_id;
 772         list_add_tail(&itte->itte_list, &device->itt_head);
 773
 774         itte->collection = collection;
 775         itte->lpi = lpi_nr;
 776
 777         irq = vgic_add_lpi(kvm, lpi_nr);
 778         if (IS_ERR(irq)) {
 779                 if (new_coll)
 780                         vgic_its_free_collection(its, coll_id);
 781                 its_free_itte(kvm, itte);
 782                 return PTR_ERR(irq);
 783         }
 784         itte->irq = irq;
 785
 786         update_affinity_itte(kvm, itte);
 787
 788         /*
 789          * We "cache" the configuration table entries in out struct vgic_irq's.
 790          * However we only have those structs for mapped IRQs, so we read in
 791          * the respective config data from memory here upon mapping the LPI.
 792          */
 793         update_lpi_config(kvm, itte->irq, NULL);
 794
 795         return 0;
 796 }
 797
 798 /* Requires the its_lock to be held. */
 799 static void vgic_its_unmap_device(struct kvm *kvm, struct its_device *device)
 800 {
 801         struct its_itte *itte, *temp;
 802
 803         /*
 804          * The spec says that unmapping a device with still valid
 805          * ITTEs associated is UNPREDICTABLE. We remove all ITTEs,
 806          * since we cannot leave the memory unreferenced.
 807          */
 808         list_for_each_entry_safe(itte, temp, &device->itt_head, itte_list)
 809                 its_free_itte(kvm, itte);
 810
 811         list_del(&device->dev_list);
 812         kfree(device);
 813 }
 814
 815 /*
 816  * MAPD maps or unmaps a device ID to Interrupt Translation Tables (ITTs).
 817  * Must be called with the its_lock mutex held.
 818  */
 819 static int vgic_its_cmd_handle_mapd(struct kvm *kvm, struct vgic_its *its,
 820                                     u64 *its_cmd)
 821 {
 822         u32 device_id = its_cmd_get_deviceid(its_cmd);
 823         bool valid = its_cmd_get_validbit(its_cmd);
 824         struct its_device *device;
 825
 826         if (!vgic_its_check_id(its, its->baser_device_table, device_id))
 827                 return E_ITS_MAPD_DEVICE_OOR;
 828
 829         device = find_its_device(its, device_id);
 830
 831         /*
 832          * The spec says that calling MAPD on an already mapped device
 833          * invalidates all cached data for this device. We implement this
 834          * by removing the mapping and re-establishing it.
 835          */
 836         if (device)
 837                 vgic_its_unmap_device(kvm, device);
 838
 839         /*
 840          * The spec does not say whether unmapping a not-mapped device
 841          * is an error, so we are done in any case.
 842          */
 843         if (!valid)
 844                 return 0;
 845
 846         device = kzalloc(sizeof(struct its_device), GFP_KERNEL);
 847         if (!device)
 848                 return -ENOMEM;
 849
 850         device->device_id = device_id;
 851         INIT_LIST_HEAD(&device->itt_head);
 852
 853         list_add_tail(&device->dev_list, &its->device_list);
 854
 855         return 0;
 856 }
 857
 858 /*
 859  * The MAPC command maps collection IDs to redistributors.
 860  * Must be called with the its_lock mutex held.
 861  */
 862 static int vgic_its_cmd_handle_mapc(struct kvm *kvm, struct vgic_its *its,
 863                                     u64 *its_cmd)
 864 {
 865         u16 coll_id;
 866         u32 target_addr;
 867         struct its_collection *collection;
 868         bool valid;
 869
 870         valid = its_cmd_get_validbit(its_cmd);
 871         coll_id = its_cmd_get_collection(its_cmd);
 872         target_addr = its_cmd_get_target_addr(its_cmd);
 873
 874         if (target_addr >= atomic_read(&kvm->online_vcpus))
 875                 return E_ITS_MAPC_PROCNUM_OOR;
 876
 877         if (!valid) {
 878                 vgic_its_free_collection(its, coll_id);
 879         } else {
 880                 collection = find_collection(its, coll_id);
 881
 882                 if (!collection) {
 883                         int ret;
 884
 885                         ret = vgic_its_alloc_collection(its, &collection,
 886                                                         coll_id);
 887                         if (ret)
 888                                 return ret;
 889                         collection->target_addr = target_addr;
 890                 } else {
 891                         collection->target_addr = target_addr;
 892                         update_affinity_collection(kvm, its, collection);
 893                 }
 894         }
 895
 896         return 0;
 897 }
 898
 899 /*
 900  * The CLEAR command removes the pending state for a particular LPI.
 901  * Must be called with the its_lock mutex held.
 902  */
 903 static int vgic_its_cmd_handle_clear(struct kvm *kvm, struct vgic_its *its,
 904                                      u64 *its_cmd)
 905 {
 906         u32 device_id = its_cmd_get_deviceid(its_cmd);
 907         u32 event_id = its_cmd_get_id(its_cmd);
 908         struct its_itte *itte;
 909
 910
 911         itte = find_itte(its, device_id, event_id);
 912         if (!itte)
 913                 return E_ITS_CLEAR_UNMAPPED_INTERRUPT;
 914
 915         itte->irq->pending = false;
 916
 917         return 0;
 918 }
 919
 920 /*
 921  * The INV command syncs the configuration bits from the memory table.
 922  * Must be called with the its_lock mutex held.
 923  */
 924 static int vgic_its_cmd_handle_inv(struct kvm *kvm, struct vgic_its *its,
 925                                    u64 *its_cmd)
 926 {
 927         u32 device_id = its_cmd_get_deviceid(its_cmd);
 928         u32 event_id = its_cmd_get_id(its_cmd);
 929         struct its_itte *itte;
 930
 931
 932         itte = find_itte(its, device_id, event_id);
 933         if (!itte)
 934                 return E_ITS_INV_UNMAPPED_INTERRUPT;
 935
 936         return update_lpi_config(kvm, itte->irq, NULL);
 937 }
 938
 939 /*
 940  * The INVALL command requests flushing of all IRQ data in this collection.
 941  * Find the VCPU mapped to that collection, then iterate over the VM's list
 942  * of mapped LPIs and update the configuration for each IRQ which targets
 943  * the specified vcpu. The configuration will be read from the in-memory
 944  * configuration table.
 945  * Must be called with the its_lock mutex held.
 946  */
 947 static int vgic_its_cmd_handle_invall(struct kvm *kvm, struct vgic_its *its,
 948                                       u64 *its_cmd)
 949 {
 950         u32 coll_id = its_cmd_get_collection(its_cmd);
 951         struct its_collection *collection;
 952         struct kvm_vcpu *vcpu;
 953         struct vgic_irq *irq;
 954         u32 *intids;
 955         int irq_count, i;
 956
 957         collection = find_collection(its, coll_id);
 958         if (!its_is_collection_mapped(collection))
 959                 return E_ITS_INVALL_UNMAPPED_COLLECTION;
 960
 961         vcpu = kvm_get_vcpu(kvm, collection->target_addr);
 962
 963         irq_count = vgic_copy_lpi_list(kvm, &intids);
 964         if (irq_count < 0)
 965                 return irq_count;
 966
 967         for (i = 0; i < irq_count; i++) {
 968                 irq = vgic_get_irq(kvm, NULL, intids[i]);
 969                 if (!irq)
 970                         continue;
 971                 update_lpi_config(kvm, irq, vcpu);
 972                 vgic_put_irq(kvm, irq);
 973         }
 974
 975         kfree(intids);
 976
 977         return 0;
 978 }
 979
 980 /*
 981  * The MOVALL command moves the pending state of all IRQs targeting one
 982  * redistributor to another. We don't hold the pending state in the VCPUs,
 983  * but in the IRQs instead, so there is really not much to do for us here.
 984  * However the spec says that no IRQ must target the old redistributor
 985  * afterwards, so we make sure that no LPI is using the associated target_vcpu.
 986  * This command affects all LPIs in the system that target that redistributor.
 987  */
 988 static int vgic_its_cmd_handle_movall(struct kvm *kvm, struct vgic_its *its,
 989                                       u64 *its_cmd)
 990 {
 991         struct vgic_dist *dist = &kvm->arch.vgic;
 992         u32 target1_addr = its_cmd_get_target_addr(its_cmd);
 993         u32 target2_addr = its_cmd_mask_field(its_cmd, 3, 16, 32);
 994         struct kvm_vcpu *vcpu1, *vcpu2;
 995         struct vgic_irq *irq;
 996
 997         if (target1_addr >= atomic_read(&kvm->online_vcpus) ||
 998             target2_addr >= atomic_read(&kvm->online_vcpus))
 999                 return E_ITS_MOVALL_PROCNUM_OOR;
1000
1001         if (target1_addr == target2_addr)
1002                 return 0;
1003
1004         vcpu1 = kvm_get_vcpu(kvm, target1_addr);
1005         vcpu2 = kvm_get_vcpu(kvm, target2_addr);
1006
1007         spin_lock(&dist->lpi_list_lock);
1008
1009         list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
1010                 spin_lock(&irq->irq_lock);
1011
1012                 if (irq->target_vcpu == vcpu1)
1013                         irq->target_vcpu = vcpu2;
1014
1015                 spin_unlock(&irq->irq_lock);
1016         }
1017
1018         spin_unlock(&dist->lpi_list_lock);
1019
1020         return 0;
1021 }
1022
1023 /*
1024  * The INT command injects the LPI associated with that DevID/EvID pair.
1025  * Must be called with the its_lock mutex held.
1026  */
1027 static int vgic_its_cmd_handle_int(struct kvm *kvm, struct vgic_its *its,
1028                                    u64 *its_cmd)
1029 {
1030         u32 msi_data = its_cmd_get_id(its_cmd);
1031         u64 msi_devid = its_cmd_get_deviceid(its_cmd);
1032
1033         return vgic_its_trigger_msi(kvm, its, msi_devid, msi_data);
1034 }
1035
1036 /*
1037  * This function is called with the its_cmd lock held, but the ITS data
1038  * structure lock dropped.
1039  */
1040 static int vgic_its_handle_command(struct kvm *kvm, struct vgic_its *its,
1041                                    u64 *its_cmd)
1042 {
1043         int ret = -ENODEV;
1044
1045         mutex_lock(&its->its_lock);
1046         switch (its_cmd_get_command(its_cmd)) {
1047         case GITS_CMD_MAPD:
1048                 ret = vgic_its_cmd_handle_mapd(kvm, its, its_cmd);
1049                 break;
1050         case GITS_CMD_MAPC:
1051                 ret = vgic_its_cmd_handle_mapc(kvm, its, its_cmd);
1052                 break;
1053         case GITS_CMD_MAPI:
1054                 ret = vgic_its_cmd_handle_mapi(kvm, its, its_cmd);
1055                 break;
1056         case GITS_CMD_MAPTI:
1057                 ret = vgic_its_cmd_handle_mapi(kvm, its, its_cmd);
1058                 break;
1059         case GITS_CMD_MOVI:
1060                 ret = vgic_its_cmd_handle_movi(kvm, its, its_cmd);
1061                 break;
1062         case GITS_CMD_DISCARD:
1063                 ret = vgic_its_cmd_handle_discard(kvm, its, its_cmd);
1064                 break;
1065         case GITS_CMD_CLEAR:
1066                 ret = vgic_its_cmd_handle_clear(kvm, its, its_cmd);
1067                 break;
1068         case GITS_CMD_MOVALL:
1069                 ret = vgic_its_cmd_handle_movall(kvm, its, its_cmd);
1070                 break;
1071         case GITS_CMD_INT:
1072                 ret = vgic_its_cmd_handle_int(kvm, its, its_cmd);
1073                 break;
1074         case GITS_CMD_INV:
1075                 ret = vgic_its_cmd_handle_inv(kvm, its, its_cmd);
1076                 break;
1077         case GITS_CMD_INVALL:
1078                 ret = vgic_its_cmd_handle_invall(kvm, its, its_cmd);
1079                 break;
1080         case GITS_CMD_SYNC:
1081                 /* we ignore this command: we are in sync all of the time */
1082                 ret = 0;
1083                 break;
1084         }
1085         mutex_unlock(&its->its_lock);
1086
1087         return ret;
1088 }
1089
1090 static u64 vgic_sanitise_its_baser(u64 reg)
1091 {
1092         reg = vgic_sanitise_field(reg, GITS_BASER_SHAREABILITY_MASK,
1093                                   GITS_BASER_SHAREABILITY_SHIFT,
1094                                   vgic_sanitise_shareability);
1095         reg = vgic_sanitise_field(reg, GITS_BASER_INNER_CACHEABILITY_MASK,
1096                                   GITS_BASER_INNER_CACHEABILITY_SHIFT,
1097                                   vgic_sanitise_inner_cacheability);
1098         reg = vgic_sanitise_field(reg, GITS_BASER_OUTER_CACHEABILITY_MASK,
1099                                   GITS_BASER_OUTER_CACHEABILITY_SHIFT,
1100                                   vgic_sanitise_outer_cacheability);
1101
1102         /* Bits 15:12 contain bits 51:48 of the PA, which we don't support. */
1103         reg &= ~GENMASK_ULL(15, 12);
1104
1105         /* We support only one (ITS) page size: 64K */
1106         reg = (reg & ~GITS_BASER_PAGE_SIZE_MASK) | GITS_BASER_PAGE_SIZE_64K;
1107
1108         return reg;
1109 }
1110
1111 static u64 vgic_sanitise_its_cbaser(u64 reg)
1112 {
1113         reg = vgic_sanitise_field(reg, GITS_CBASER_SHAREABILITY_MASK,
1114                                   GITS_CBASER_SHAREABILITY_SHIFT,
1115                                   vgic_sanitise_shareability);
1116         reg = vgic_sanitise_field(reg, GITS_CBASER_INNER_CACHEABILITY_MASK,
1117                                   GITS_CBASER_INNER_CACHEABILITY_SHIFT,
1118                                   vgic_sanitise_inner_cacheability);
1119         reg = vgic_sanitise_field(reg, GITS_CBASER_OUTER_CACHEABILITY_MASK,
1120                                   GITS_CBASER_OUTER_CACHEABILITY_SHIFT,
1121                                   vgic_sanitise_outer_cacheability);
1122
1123         /*
1124          * Sanitise the physical address to be 64k aligned.
1125          * Also limit the physical addresses to 48 bits.
1126          */
1127         reg &= ~(GENMASK_ULL(51, 48) | GENMASK_ULL(15, 12));
1128
1129         return reg;
1130 }
1131
1132 static unsigned long vgic_mmio_read_its_cbaser(struct kvm *kvm,
1133                                                struct vgic_its *its,
1134                                                gpa_t addr, unsigned int len)
1135 {
1136         return extract_bytes(its->cbaser, addr & 7, len);
1137 }
1138
1139 static void vgic_mmio_write_its_cbaser(struct kvm *kvm, struct vgic_its *its,
1140                                        gpa_t addr, unsigned int len,
1141                                        unsigned long val)
1142 {
1143         /* When GITS_CTLR.Enable is 1, this register is RO. */
1144         if (its->enabled)
1145                 return;
1146
1147         mutex_lock(&its->cmd_lock);
1148         its->cbaser = update_64bit_reg(its->cbaser, addr & 7, len, val);
1149         its->cbaser = vgic_sanitise_its_cbaser(its->cbaser);
1150         its->creadr = 0;
1151         /*
1152          * CWRITER is architecturally UNKNOWN on reset, but we need to reset
1153          * it to CREADR to make sure we start with an empty command buffer.
1154          */
1155         its->cwriter = its->creadr;
1156         mutex_unlock(&its->cmd_lock);
1157 }
1158
1159 #define ITS_CMD_BUFFER_SIZE(baser)      ((((baser) & 0xff) + 1) << 12)
1160 #define ITS_CMD_SIZE                    32
1161 #define ITS_CMD_OFFSET(reg)             ((reg) & GENMASK(19, 5))
1162
1163 /*
1164  * By writing to CWRITER the guest announces new commands to be processed.
1165  * To avoid any races in the first place, we take the its_cmd lock, which
1166  * protects our ring buffer variables, so that there is only one user
1167  * per ITS handling commands at a given time.
1168  */
1169 static void vgic_mmio_write_its_cwriter(struct kvm *kvm, struct vgic_its *its,
1170                                         gpa_t addr, unsigned int len,
1171                                         unsigned long val)
1172 {
1173         gpa_t cbaser;
1174         u64 cmd_buf[4];
1175         u32 reg;
1176
1177         if (!its)
1178                 return;
1179
1180         mutex_lock(&its->cmd_lock);
1181
1182         reg = update_64bit_reg(its->cwriter, addr & 7, len, val);
1183         reg = ITS_CMD_OFFSET(reg);
1184         if (reg >= ITS_CMD_BUFFER_SIZE(its->cbaser)) {
1185                 mutex_unlock(&its->cmd_lock);
1186                 return;
1187         }
1188
1189         its->cwriter = reg;
1190         cbaser = CBASER_ADDRESS(its->cbaser);
1191
1192         while (its->cwriter != its->creadr) {
1193                 int ret = kvm_read_guest(kvm, cbaser + its->creadr,
1194                                          cmd_buf, ITS_CMD_SIZE);
1195                 /*
1196                  * If kvm_read_guest() fails, this could be due to the guest
1197                  * programming a bogus value in CBASER or something else going
1198                  * wrong from which we cannot easily recover.
1199                  * According to section 6.3.2 in the GICv3 spec we can just
1200                  * ignore that command then.
1201                  */
1202                 if (!ret)
1203                         vgic_its_handle_command(kvm, its, cmd_buf);
1204
1205                 its->creadr += ITS_CMD_SIZE;
1206                 if (its->creadr == ITS_CMD_BUFFER_SIZE(its->cbaser))
1207                         its->creadr = 0;
1208         }
1209
1210         mutex_unlock(&its->cmd_lock);
1211 }
1212
1213 static unsigned long vgic_mmio_read_its_cwriter(struct kvm *kvm,
1214                                                 struct vgic_its *its,
1215                                                 gpa_t addr, unsigned int len)
1216 {
1217         return extract_bytes(its->cwriter, addr & 0x7, len);
1218 }
1219
1220 static unsigned long vgic_mmio_read_its_creadr(struct kvm *kvm,
1221                                                struct vgic_its *its,
1222                                                gpa_t addr, unsigned int len)
1223 {
1224         return extract_bytes(its->creadr, addr & 0x7, len);
1225 }
1226
1227 #define BASER_INDEX(addr) (((addr) / sizeof(u64)) & 0x7)
1228 static unsigned long vgic_mmio_read_its_baser(struct kvm *kvm,
1229                                               struct vgic_its *its,
1230                                               gpa_t addr, unsigned int len)
1231 {
1232         u64 reg;
1233
1234         switch (BASER_INDEX(addr)) {
1235         case 0:
1236                 reg = its->baser_device_table;
1237                 break;
1238         case 1:
1239                 reg = its->baser_coll_table;
1240                 break;
1241         default:
1242                 reg = 0;
1243                 break;
1244         }
1245
1246         return extract_bytes(reg, addr & 7, len);
1247 }
1248
1249 #define GITS_BASER_RO_MASK      (GENMASK_ULL(52, 48) | GENMASK_ULL(58, 56))
1250 static void vgic_mmio_write_its_baser(struct kvm *kvm,
1251                                       struct vgic_its *its,
1252                                       gpa_t addr, unsigned int len,
1253                                       unsigned long val)
1254 {
1255         u64 entry_size, device_type;
1256         u64 reg, *regptr, clearbits = 0;
1257
1258         /* When GITS_CTLR.Enable is 1, we ignore write accesses. */
1259         if (its->enabled)
1260                 return;
1261
1262         switch (BASER_INDEX(addr)) {
1263         case 0:
1264                 regptr = &its->baser_device_table;
1265                 entry_size = 8;
1266                 device_type = GITS_BASER_TYPE_DEVICE;
1267                 break;
1268         case 1:
1269                 regptr = &its->baser_coll_table;
1270                 entry_size = 8;
1271                 device_type = GITS_BASER_TYPE_COLLECTION;
1272                 clearbits = GITS_BASER_INDIRECT;
1273                 break;
1274         default:
1275                 return;
1276         }
1277
1278         reg = update_64bit_reg(*regptr, addr & 7, len, val);
1279         reg &= ~GITS_BASER_RO_MASK;
1280         reg &= ~clearbits;
1281
1282         reg |= (entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT;
1283         reg |= device_type << GITS_BASER_TYPE_SHIFT;
1284         reg = vgic_sanitise_its_baser(reg);
1285
1286         *regptr = reg;
1287 }
1288
1289 #define REGISTER_ITS_DESC(off, rd, wr, length, acc)             \
1290 {                                                               \
1291         .reg_offset = off,                                      \
1292         .len = length,                                          \
1293         .access_flags = acc,                                    \
1294         .its_read = rd,                                         \
1295         .its_write = wr,                                        \
1296 }
1297
1298 static void its_mmio_write_wi(struct kvm *kvm, struct vgic_its *its,
1299                               gpa_t addr, unsigned int len, unsigned long val)
1300 {
1301         /* Ignore */
1302 }
1303
1304 static struct vgic_register_region its_registers[] = {
1305         REGISTER_ITS_DESC(GITS_CTLR,
1306                 vgic_mmio_read_its_ctlr, vgic_mmio_write_its_ctlr, 4,
1307                 VGIC_ACCESS_32bit),
1308         REGISTER_ITS_DESC(GITS_IIDR,
1309                 vgic_mmio_read_its_iidr, its_mmio_write_wi, 4,
1310                 VGIC_ACCESS_32bit),
1311         REGISTER_ITS_DESC(GITS_TYPER,
1312                 vgic_mmio_read_its_typer, its_mmio_write_wi, 8,
1313                 VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
1314         REGISTER_ITS_DESC(GITS_CBASER,
1315                 vgic_mmio_read_its_cbaser, vgic_mmio_write_its_cbaser, 8,
1316                 VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
1317         REGISTER_ITS_DESC(GITS_CWRITER,
1318                 vgic_mmio_read_its_cwriter, vgic_mmio_write_its_cwriter, 8,
1319                 VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
1320         REGISTER_ITS_DESC(GITS_CREADR,
1321                 vgic_mmio_read_its_creadr, its_mmio_write_wi, 8,
1322                 VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
1323         REGISTER_ITS_DESC(GITS_BASER,
1324                 vgic_mmio_read_its_baser, vgic_mmio_write_its_baser, 0x40,
1325                 VGIC_ACCESS_64bit | VGIC_ACCESS_32bit),
1326         REGISTER_ITS_DESC(GITS_IDREGS_BASE,
1327                 vgic_mmio_read_its_idregs, its_mmio_write_wi, 0x30,
1328                 VGIC_ACCESS_32bit),
1329 };
1330
1331 /* This is called on setting the LPI enable bit in the redistributor. */
1332 void vgic_enable_lpis(struct kvm_vcpu *vcpu)
1333 {
1334         if (!(vcpu->arch.vgic_cpu.pendbaser & GICR_PENDBASER_PTZ))
1335                 its_sync_lpi_pending_table(vcpu);
1336 }
1337
1338 static int vgic_register_its_iodev(struct kvm *kvm, struct vgic_its *its)
1339 {
1340         struct vgic_io_device *iodev = &its->iodev;
1341         int ret;
1342
1343         if (!its->initialized)
1344                 return -EBUSY;
1345
1346         if (IS_VGIC_ADDR_UNDEF(its->vgic_its_base))
1347                 return -ENXIO;
1348
1349         iodev->regions = its_registers;
1350         iodev->nr_regions = ARRAY_SIZE(its_registers);
1351         kvm_iodevice_init(&iodev->dev, &kvm_io_gic_ops);
1352
1353         iodev->base_addr = its->vgic_its_base;
1354         iodev->iodev_type = IODEV_ITS;
1355         iodev->its = its;
1356         mutex_lock(&kvm->slots_lock);
1357         ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, iodev->base_addr,
1358                                       KVM_VGIC_V3_ITS_SIZE, &iodev->dev);
1359         mutex_unlock(&kvm->slots_lock);
1360
1361         return ret;
1362 }
1363
1364 #define INITIAL_BASER_VALUE                                               \
1365         (GIC_BASER_CACHEABILITY(GITS_BASER, INNER, RaWb)                | \
1366          GIC_BASER_CACHEABILITY(GITS_BASER, OUTER, SameAsInner)         | \
1367          GIC_BASER_SHAREABILITY(GITS_BASER, InnerShareable)             | \
1368          ((8ULL - 1) << GITS_BASER_ENTRY_SIZE_SHIFT)                    | \
1369          GITS_BASER_PAGE_SIZE_64K)
1370
1371 #define INITIAL_PROPBASER_VALUE                                           \
1372         (GIC_BASER_CACHEABILITY(GICR_PROPBASER, INNER, RaWb)            | \
1373          GIC_BASER_CACHEABILITY(GICR_PROPBASER, OUTER, SameAsInner)     | \
1374          GIC_BASER_SHAREABILITY(GICR_PROPBASER, InnerShareable))
1375
1376 static int vgic_its_create(struct kvm_device *dev, u32 type)
1377 {
1378         struct vgic_its *its;
1379
1380         if (type != KVM_DEV_TYPE_ARM_VGIC_ITS)
1381                 return -ENODEV;
1382
1383         its = kzalloc(sizeof(struct vgic_its), GFP_KERNEL);
1384         if (!its)
1385                 return -ENOMEM;
1386
1387         mutex_init(&its->its_lock);
1388         mutex_init(&its->cmd_lock);
1389
1390         its->vgic_its_base = VGIC_ADDR_UNDEF;
1391
1392         INIT_LIST_HEAD(&its->device_list);
1393         INIT_LIST_HEAD(&its->collection_list);
1394
1395         dev->kvm->arch.vgic.has_its = true;
1396         its->initialized = false;
1397         its->enabled = false;
1398         its->dev = dev;
1399
1400         its->baser_device_table = INITIAL_BASER_VALUE                   |
1401                 ((u64)GITS_BASER_TYPE_DEVICE << GITS_BASER_TYPE_SHIFT);
1402         its->baser_coll_table = INITIAL_BASER_VALUE |
1403                 ((u64)GITS_BASER_TYPE_COLLECTION << GITS_BASER_TYPE_SHIFT);
1404         dev->kvm->arch.vgic.propbaser = INITIAL_PROPBASER_VALUE;
1405
1406         dev->private = its;
1407
1408         return 0;
1409 }
1410
1411 static void vgic_its_destroy(struct kvm_device *kvm_dev)
1412 {
1413         struct kvm *kvm = kvm_dev->kvm;
1414         struct vgic_its *its = kvm_dev->private;
1415         struct its_device *dev;
1416         struct its_itte *itte;
1417         struct list_head *dev_cur, *dev_temp;
1418         struct list_head *cur, *temp;
1419
1420         /*
1421          * We may end up here without the lists ever having been initialized.
1422          * Check this and bail out early to avoid dereferencing a NULL pointer.
1423          */
1424         if (!its->device_list.next)
1425                 return;
1426
1427         mutex_lock(&its->its_lock);
1428         list_for_each_safe(dev_cur, dev_temp, &its->device_list) {
1429                 dev = container_of(dev_cur, struct its_device, dev_list);
1430                 list_for_each_safe(cur, temp, &dev->itt_head) {
1431                         itte = (container_of(cur, struct its_itte, itte_list));
1432                         its_free_itte(kvm, itte);
1433                 }
1434                 list_del(dev_cur);
1435                 kfree(dev);
1436         }
1437
1438         list_for_each_safe(cur, temp, &its->collection_list) {
1439                 list_del(cur);
1440                 kfree(container_of(cur, struct its_collection, coll_list));
1441         }
1442         mutex_unlock(&its->its_lock);
1443
1444         kfree(its);
1445 }
1446
1447 static int vgic_its_has_attr(struct kvm_device *dev,
1448                              struct kvm_device_attr *attr)
1449 {
1450         switch (attr->group) {
1451         case KVM_DEV_ARM_VGIC_GRP_ADDR:
1452                 switch (attr->attr) {
1453                 case KVM_VGIC_ITS_ADDR_TYPE:
1454                         return 0;
1455                 }
1456                 break;
1457         case KVM_DEV_ARM_VGIC_GRP_CTRL:
1458                 switch (attr->attr) {
1459                 case KVM_DEV_ARM_VGIC_CTRL_INIT:
1460                         return 0;
1461                 }
1462                 break;
1463         }
1464         return -ENXIO;
1465 }
1466
1467 static int vgic_its_set_attr(struct kvm_device *dev,
1468                              struct kvm_device_attr *attr)
1469 {
1470         struct vgic_its *its = dev->private;
1471         int ret;
1472
1473         switch (attr->group) {
1474         case KVM_DEV_ARM_VGIC_GRP_ADDR: {
1475                 u64 __user *uaddr = (u64 __user *)(long)attr->addr;
1476                 unsigned long type = (unsigned long)attr->attr;
1477                 u64 addr;
1478
1479                 if (type != KVM_VGIC_ITS_ADDR_TYPE)
1480                         return -ENODEV;
1481
1482                 if (copy_from_user(&addr, uaddr, sizeof(addr)))
1483                         return -EFAULT;
1484
1485                 ret = vgic_check_ioaddr(dev->kvm, &its->vgic_its_base,
1486                                         addr, SZ_64K);
1487                 if (ret)
1488                         return ret;
1489
1490                 its->vgic_its_base = addr;
1491
1492                 return 0;
1493         }
1494         case KVM_DEV_ARM_VGIC_GRP_CTRL:
1495                 switch (attr->attr) {
1496                 case KVM_DEV_ARM_VGIC_CTRL_INIT:
1497                         its->initialized = true;
1498
1499                         return 0;
1500                 }
1501                 break;
1502         }
1503         return -ENXIO;
1504 }
1505
1506 static int vgic_its_get_attr(struct kvm_device *dev,
1507                              struct kvm_device_attr *attr)
1508 {
1509         switch (attr->group) {
1510         case KVM_DEV_ARM_VGIC_GRP_ADDR: {
1511                 struct vgic_its *its = dev->private;
1512                 u64 addr = its->vgic_its_base;
1513                 u64 __user *uaddr = (u64 __user *)(long)attr->addr;
1514                 unsigned long type = (unsigned long)attr->attr;
1515
1516                 if (type != KVM_VGIC_ITS_ADDR_TYPE)
1517                         return -ENODEV;
1518
1519                 if (copy_to_user(uaddr, &addr, sizeof(addr)))
1520                         return -EFAULT;
1521                 break;
1522         default:
1523                 return -ENXIO;
1524         }
1525         }
1526
1527         return 0;
1528 }
1529
1530 static struct kvm_device_ops kvm_arm_vgic_its_ops = {
1531         .name = "kvm-arm-vgic-its",
1532         .create = vgic_its_create,
1533         .destroy = vgic_its_destroy,
1534         .set_attr = vgic_its_set_attr,
1535         .get_attr = vgic_its_get_attr,
1536         .has_attr = vgic_its_has_attr,
1537 };
1538
1539 int kvm_vgic_register_its_device(void)
1540 {
1541         return kvm_register_device_ops(&kvm_arm_vgic_its_ops,
1542                                        KVM_DEV_TYPE_ARM_VGIC_ITS);
1543 }
1544
1545 /*
1546  * Registers all ITSes with the kvm_io_bus framework.
1547  * To follow the existing VGIC initialization sequence, this has to be
1548  * done as late as possible, just before the first VCPU runs.
1549  */
1550 int vgic_register_its_iodevs(struct kvm *kvm)
1551 {
1552         struct kvm_device *dev;
1553         int ret = 0;
1554
1555         list_for_each_entry(dev, &kvm->devices, vm_node) {
1556                 if (dev->ops != &kvm_arm_vgic_its_ops)
1557                         continue;
1558
1559                 ret = vgic_register_its_iodev(kvm, dev->private);
1560                 if (ret)
1561                         return ret;
1562                 /*
1563                  * We don't need to care about tearing down previously
1564                  * registered ITSes, as the kvm_io_bus framework removes
1565                  * them for us if the VM gets destroyed.
1566                  */
1567         }
1568
1569         return ret;
1570 }