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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 | /* * Copyright 2014 IBM Corp. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/pci.h> #include <linux/slab.h> #include <linux/file.h> #include <misc/cxl.h> #include <linux/msi.h> #include <linux/module.h> #include <linux/mount.h> #include <linux/sched/mm.h> #include <linux/mmu_context.h> #include "cxl.h" /* * Since we want to track memory mappings to be able to force-unmap * when the AFU is no longer reachable, we need an inode. For devices * opened through the cxl user API, this is not a problem, but a * userland process can also get a cxl fd through the cxl_get_fd() * API, which is used by the cxlflash driver. * * Therefore we implement our own simple pseudo-filesystem and inode * allocator. We don't use the anonymous inode, as we need the * meta-data associated with it (address_space) and it is shared by * other drivers/processes, so it could lead to cxl unmapping VMAs * from random processes. */ #define CXL_PSEUDO_FS_MAGIC 0x1697697f static int cxl_fs_cnt; static struct vfsmount *cxl_vfs_mount; static const struct dentry_operations cxl_fs_dops = { .d_dname = simple_dname, }; static struct dentry *cxl_fs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { return mount_pseudo(fs_type, "cxl:", NULL, &cxl_fs_dops, CXL_PSEUDO_FS_MAGIC); } static struct file_system_type cxl_fs_type = { .name = "cxl", .owner = THIS_MODULE, .mount = cxl_fs_mount, .kill_sb = kill_anon_super, }; void cxl_release_mapping(struct cxl_context *ctx) { if (ctx->kernelapi && ctx->mapping) simple_release_fs(&cxl_vfs_mount, &cxl_fs_cnt); } static struct file *cxl_getfile(const char *name, const struct file_operations *fops, void *priv, int flags) { struct qstr this; struct path path; struct file *file; struct inode *inode = NULL; int rc; /* strongly inspired by anon_inode_getfile() */ if (fops->owner && !try_module_get(fops->owner)) return ERR_PTR(-ENOENT); rc = simple_pin_fs(&cxl_fs_type, &cxl_vfs_mount, &cxl_fs_cnt); if (rc < 0) { pr_err("Cannot mount cxl pseudo filesystem: %d\n", rc); file = ERR_PTR(rc); goto err_module; } inode = alloc_anon_inode(cxl_vfs_mount->mnt_sb); if (IS_ERR(inode)) { file = ERR_CAST(inode); goto err_fs; } file = ERR_PTR(-ENOMEM); this.name = name; this.len = strlen(name); this.hash = 0; path.dentry = d_alloc_pseudo(cxl_vfs_mount->mnt_sb, &this); if (!path.dentry) goto err_inode; path.mnt = mntget(cxl_vfs_mount); d_instantiate(path.dentry, inode); file = alloc_file(&path, OPEN_FMODE(flags), fops); if (IS_ERR(file)) goto err_dput; file->f_flags = flags & (O_ACCMODE | O_NONBLOCK); file->private_data = priv; return file; err_dput: path_put(&path); err_inode: iput(inode); err_fs: simple_release_fs(&cxl_vfs_mount, &cxl_fs_cnt); err_module: module_put(fops->owner); return file; } struct cxl_context *cxl_dev_context_init(struct pci_dev *dev) { struct cxl_afu *afu; struct cxl_context *ctx; int rc; afu = cxl_pci_to_afu(dev); if (IS_ERR(afu)) return ERR_CAST(afu); ctx = cxl_context_alloc(); if (!ctx) return ERR_PTR(-ENOMEM); ctx->kernelapi = true; /* Make it a slave context. We can promote it later? */ rc = cxl_context_init(ctx, afu, false); if (rc) goto err_ctx; return ctx; err_ctx: kfree(ctx); return ERR_PTR(rc); } EXPORT_SYMBOL_GPL(cxl_dev_context_init); struct cxl_context *cxl_get_context(struct pci_dev *dev) { return dev->dev.archdata.cxl_ctx; } EXPORT_SYMBOL_GPL(cxl_get_context); int cxl_release_context(struct cxl_context *ctx) { if (ctx->status >= STARTED) return -EBUSY; cxl_context_free(ctx); return 0; } EXPORT_SYMBOL_GPL(cxl_release_context); static irq_hw_number_t cxl_find_afu_irq(struct cxl_context *ctx, int num) { __u16 range; int r; for (r = 0; r < CXL_IRQ_RANGES; r++) { range = ctx->irqs.range[r]; if (num < range) { return ctx->irqs.offset[r] + num; } num -= range; } return 0; } int _cxl_next_msi_hwirq(struct pci_dev *pdev, struct cxl_context **ctx, int *afu_irq) { if (*ctx == NULL || *afu_irq == 0) { *afu_irq = 1; *ctx = cxl_get_context(pdev); } else { (*afu_irq)++; if (*afu_irq > cxl_get_max_irqs_per_process(pdev)) { *ctx = list_next_entry(*ctx, extra_irq_contexts); *afu_irq = 1; } } return cxl_find_afu_irq(*ctx, *afu_irq); } /* Exported via cxl_base */ int cxl_set_priv(struct cxl_context *ctx, void *priv) { if (!ctx) return -EINVAL; ctx->priv = priv; return 0; } EXPORT_SYMBOL_GPL(cxl_set_priv); void *cxl_get_priv(struct cxl_context *ctx) { if (!ctx) return ERR_PTR(-EINVAL); return ctx->priv; } EXPORT_SYMBOL_GPL(cxl_get_priv); int cxl_allocate_afu_irqs(struct cxl_context *ctx, int num) { int res; irq_hw_number_t hwirq; if (num == 0) num = ctx->afu->pp_irqs; res = afu_allocate_irqs(ctx, num); if (res) return res; if (!cpu_has_feature(CPU_FTR_HVMODE)) { /* In a guest, the PSL interrupt is not multiplexed. It was * allocated above, and we need to set its handler */ hwirq = cxl_find_afu_irq(ctx, 0); if (hwirq) cxl_map_irq(ctx->afu->adapter, hwirq, cxl_ops->psl_interrupt, ctx, "psl"); } if (ctx->status == STARTED) { if (cxl_ops->update_ivtes) cxl_ops->update_ivtes(ctx); else WARN(1, "BUG: cxl_allocate_afu_irqs must be called prior to starting the context on this platform\n"); } return res; } EXPORT_SYMBOL_GPL(cxl_allocate_afu_irqs); void cxl_free_afu_irqs(struct cxl_context *ctx) { irq_hw_number_t hwirq; unsigned int virq; if (!cpu_has_feature(CPU_FTR_HVMODE)) { hwirq = cxl_find_afu_irq(ctx, 0); if (hwirq) { virq = irq_find_mapping(NULL, hwirq); if (virq) cxl_unmap_irq(virq, ctx); } } afu_irq_name_free(ctx); cxl_ops->release_irq_ranges(&ctx->irqs, ctx->afu->adapter); } EXPORT_SYMBOL_GPL(cxl_free_afu_irqs); int cxl_map_afu_irq(struct cxl_context *ctx, int num, irq_handler_t handler, void *cookie, char *name) { irq_hw_number_t hwirq; /* * Find interrupt we are to register. */ hwirq = cxl_find_afu_irq(ctx, num); if (!hwirq) return -ENOENT; return cxl_map_irq(ctx->afu->adapter, hwirq, handler, cookie, name); } EXPORT_SYMBOL_GPL(cxl_map_afu_irq); void cxl_unmap_afu_irq(struct cxl_context *ctx, int num, void *cookie) { irq_hw_number_t hwirq; unsigned int virq; hwirq = cxl_find_afu_irq(ctx, num); if (!hwirq) return; virq = irq_find_mapping(NULL, hwirq); if (virq) cxl_unmap_irq(virq, cookie); } EXPORT_SYMBOL_GPL(cxl_unmap_afu_irq); /* * Start a context * Code here similar to afu_ioctl_start_work(). */ int cxl_start_context(struct cxl_context *ctx, u64 wed, struct task_struct *task) { int rc = 0; bool kernel = true; pr_devel("%s: pe: %i\n", __func__, ctx->pe); mutex_lock(&ctx->status_mutex); if (ctx->status == STARTED) goto out; /* already started */ /* * Increment the mapped context count for adapter. This also checks * if adapter_context_lock is taken. */ rc = cxl_adapter_context_get(ctx->afu->adapter); if (rc) goto out; if (task) { ctx->pid = get_task_pid(task, PIDTYPE_PID); kernel = false; ctx->real_mode = false; /* acquire a reference to the task's mm */ ctx->mm = get_task_mm(current); /* ensure this mm_struct can't be freed */ cxl_context_mm_count_get(ctx); if (ctx->mm) { /* decrement the use count from above */ mmput(ctx->mm); /* make TLBIs for this context global */ mm_context_add_copro(ctx->mm); } } /* * Increment driver use count. Enables global TLBIs for hash * and callbacks to handle the segment table */ cxl_ctx_get(); /* See the comment in afu_ioctl_start_work() */ smp_mb(); if ((rc = cxl_ops->attach_process(ctx, kernel, wed, 0))) { put_pid(ctx->pid); ctx->pid = NULL; cxl_adapter_context_put(ctx->afu->adapter); cxl_ctx_put(); if (task) { cxl_context_mm_count_put(ctx); if (ctx->mm) mm_context_remove_copro(ctx->mm); } goto out; } ctx->status = STARTED; out: mutex_unlock(&ctx->status_mutex); return rc; } EXPORT_SYMBOL_GPL(cxl_start_context); int cxl_process_element(struct cxl_context *ctx) { return ctx->external_pe; } EXPORT_SYMBOL_GPL(cxl_process_element); /* Stop a context. Returns 0 on success, otherwise -Errno */ int cxl_stop_context(struct cxl_context *ctx) { return __detach_context(ctx); } EXPORT_SYMBOL_GPL(cxl_stop_context); void cxl_set_master(struct cxl_context *ctx) { ctx->master = true; } EXPORT_SYMBOL_GPL(cxl_set_master); int cxl_set_translation_mode(struct cxl_context *ctx, bool real_mode) { if (ctx->status == STARTED) { /* * We could potentially update the PE and issue an update LLCMD * to support this, but it doesn't seem to have a good use case * since it's trivial to just create a second kernel context * with different translation modes, so until someone convinces * me otherwise: */ return -EBUSY; } ctx->real_mode = real_mode; return 0; } EXPORT_SYMBOL_GPL(cxl_set_translation_mode); /* wrappers around afu_* file ops which are EXPORTED */ int cxl_fd_open(struct inode *inode, struct file *file) { return afu_open(inode, file); } EXPORT_SYMBOL_GPL(cxl_fd_open); int cxl_fd_release(struct inode *inode, struct file *file) { return afu_release(inode, file); } EXPORT_SYMBOL_GPL(cxl_fd_release); long cxl_fd_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { return afu_ioctl(file, cmd, arg); } EXPORT_SYMBOL_GPL(cxl_fd_ioctl); int cxl_fd_mmap(struct file *file, struct vm_area_struct *vm) { return afu_mmap(file, vm); } EXPORT_SYMBOL_GPL(cxl_fd_mmap); __poll_t cxl_fd_poll(struct file *file, struct poll_table_struct *poll) { return afu_poll(file, poll); } EXPORT_SYMBOL_GPL(cxl_fd_poll); ssize_t cxl_fd_read(struct file *file, char __user *buf, size_t count, loff_t *off) { return afu_read(file, buf, count, off); } EXPORT_SYMBOL_GPL(cxl_fd_read); #define PATCH_FOPS(NAME) if (!fops->NAME) fops->NAME = afu_fops.NAME /* Get a struct file and fd for a context and attach the ops */ struct file *cxl_get_fd(struct cxl_context *ctx, struct file_operations *fops, int *fd) { struct file *file; int rc, flags, fdtmp; char *name = NULL; /* only allow one per context */ if (ctx->mapping) return ERR_PTR(-EEXIST); flags = O_RDWR | O_CLOEXEC; /* This code is similar to anon_inode_getfd() */ rc = get_unused_fd_flags(flags); if (rc < 0) return ERR_PTR(rc); fdtmp = rc; /* * Patch the file ops. Needs to be careful that this is rentrant safe. */ if (fops) { PATCH_FOPS(open); PATCH_FOPS(poll); PATCH_FOPS(read); PATCH_FOPS(release); PATCH_FOPS(unlocked_ioctl); PATCH_FOPS(compat_ioctl); PATCH_FOPS(mmap); } else /* use default ops */ fops = (struct file_operations *)&afu_fops; name = kasprintf(GFP_KERNEL, "cxl:%d", ctx->pe); file = cxl_getfile(name, fops, ctx, flags); kfree(name); if (IS_ERR(file)) goto err_fd; cxl_context_set_mapping(ctx, file->f_mapping); *fd = fdtmp; return file; err_fd: put_unused_fd(fdtmp); return NULL; } EXPORT_SYMBOL_GPL(cxl_get_fd); struct cxl_context *cxl_fops_get_context(struct file *file) { return file->private_data; } EXPORT_SYMBOL_GPL(cxl_fops_get_context); void cxl_set_driver_ops(struct cxl_context *ctx, struct cxl_afu_driver_ops *ops) { WARN_ON(!ops->fetch_event || !ops->event_delivered); atomic_set(&ctx->afu_driver_events, 0); ctx->afu_driver_ops = ops; } EXPORT_SYMBOL_GPL(cxl_set_driver_ops); void cxl_context_events_pending(struct cxl_context *ctx, unsigned int new_events) { atomic_add(new_events, &ctx->afu_driver_events); wake_up_all(&ctx->wq); } EXPORT_SYMBOL_GPL(cxl_context_events_pending); int cxl_start_work(struct cxl_context *ctx, struct cxl_ioctl_start_work *work) { int rc; /* code taken from afu_ioctl_start_work */ if (!(work->flags & CXL_START_WORK_NUM_IRQS)) work->num_interrupts = ctx->afu->pp_irqs; else if ((work->num_interrupts < ctx->afu->pp_irqs) || (work->num_interrupts > ctx->afu->irqs_max)) { return -EINVAL; } rc = afu_register_irqs(ctx, work->num_interrupts); if (rc) return rc; rc = cxl_start_context(ctx, work->work_element_descriptor, current); if (rc < 0) { afu_release_irqs(ctx, ctx); return rc; } return 0; } EXPORT_SYMBOL_GPL(cxl_start_work); void __iomem *cxl_psa_map(struct cxl_context *ctx) { if (ctx->status != STARTED) return NULL; pr_devel("%s: psn_phys%llx size:%llx\n", __func__, ctx->psn_phys, ctx->psn_size); return ioremap(ctx->psn_phys, ctx->psn_size); } EXPORT_SYMBOL_GPL(cxl_psa_map); void cxl_psa_unmap(void __iomem *addr) { iounmap(addr); } EXPORT_SYMBOL_GPL(cxl_psa_unmap); int cxl_afu_reset(struct cxl_context *ctx) { struct cxl_afu *afu = ctx->afu; int rc; rc = cxl_ops->afu_reset(afu); if (rc) return rc; return cxl_ops->afu_check_and_enable(afu); } EXPORT_SYMBOL_GPL(cxl_afu_reset); void cxl_perst_reloads_same_image(struct cxl_afu *afu, bool perst_reloads_same_image) { afu->adapter->perst_same_image = perst_reloads_same_image; } EXPORT_SYMBOL_GPL(cxl_perst_reloads_same_image); ssize_t cxl_read_adapter_vpd(struct pci_dev *dev, void *buf, size_t count) { struct cxl_afu *afu = cxl_pci_to_afu(dev); if (IS_ERR(afu)) return -ENODEV; return cxl_ops->read_adapter_vpd(afu->adapter, buf, count); } EXPORT_SYMBOL_GPL(cxl_read_adapter_vpd); int cxl_set_max_irqs_per_process(struct pci_dev *dev, int irqs) { struct cxl_afu *afu = cxl_pci_to_afu(dev); if (IS_ERR(afu)) return -ENODEV; if (irqs > afu->adapter->user_irqs) return -EINVAL; /* Limit user_irqs to prevent the user increasing this via sysfs */ afu->adapter->user_irqs = irqs; afu->irqs_max = irqs; return 0; } EXPORT_SYMBOL_GPL(cxl_set_max_irqs_per_process); int cxl_get_max_irqs_per_process(struct pci_dev *dev) { struct cxl_afu *afu = cxl_pci_to_afu(dev); if (IS_ERR(afu)) return -ENODEV; return afu->irqs_max; } EXPORT_SYMBOL_GPL(cxl_get_max_irqs_per_process); /* * This is a special interrupt allocation routine called from the PHB's MSI * setup function. When capi interrupts are allocated in this manner they must * still be associated with a running context, but since the MSI APIs have no * way to specify this we use the default context associated with the device. * * The Mellanox CX4 has a hardware limitation that restricts the maximum AFU * interrupt number, so in order to overcome this their driver informs us of * the restriction by setting the maximum interrupts per context, and we * allocate additional contexts as necessary so that we can keep the AFU * interrupt number within the supported range. */ int _cxl_cx4_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type) { struct cxl_context *ctx, *new_ctx, *default_ctx; int remaining; int rc; ctx = default_ctx = cxl_get_context(pdev); if (WARN_ON(!default_ctx)) return -ENODEV; remaining = nvec; while (remaining > 0) { rc = cxl_allocate_afu_irqs(ctx, min(remaining, ctx->afu->irqs_max)); if (rc) { pr_warn("%s: Failed to find enough free MSIs\n", pci_name(pdev)); return rc; } remaining -= ctx->afu->irqs_max; if (ctx != default_ctx && default_ctx->status == STARTED) { WARN_ON(cxl_start_context(ctx, be64_to_cpu(default_ctx->elem->common.wed), NULL)); } if (remaining > 0) { new_ctx = cxl_dev_context_init(pdev); if (IS_ERR(new_ctx)) { pr_warn("%s: Failed to allocate enough contexts for MSIs\n", pci_name(pdev)); return -ENOSPC; } list_add(&new_ctx->extra_irq_contexts, &ctx->extra_irq_contexts); ctx = new_ctx; } } return 0; } /* Exported via cxl_base */ void _cxl_cx4_teardown_msi_irqs(struct pci_dev *pdev) { struct cxl_context *ctx, *pos, *tmp; ctx = cxl_get_context(pdev); if (WARN_ON(!ctx)) return; cxl_free_afu_irqs(ctx); list_for_each_entry_safe(pos, tmp, &ctx->extra_irq_contexts, extra_irq_contexts) { cxl_stop_context(pos); cxl_free_afu_irqs(pos); list_del(&pos->extra_irq_contexts); cxl_release_context(pos); } } /* Exported via cxl_base */ |