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1// SPDX-License-Identifier: GPL-2.0-only2/******************************************************************************3 * privcmd.c4 *5 * Interface to privileged domain-0 commands.6 *7 * Copyright (c) 2002-2004, K A Fraser, B Dragovic8 */9 10#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt11 12#include <linux/eventfd.h>13#include <linux/file.h>14#include <linux/kernel.h>15#include <linux/module.h>16#include <linux/mutex.h>17#include <linux/poll.h>18#include <linux/sched.h>19#include <linux/slab.h>20#include <linux/srcu.h>21#include <linux/string.h>22#include <linux/workqueue.h>23#include <linux/errno.h>24#include <linux/mm.h>25#include <linux/mman.h>26#include <linux/uaccess.h>27#include <linux/swap.h>28#include <linux/highmem.h>29#include <linux/pagemap.h>30#include <linux/seq_file.h>31#include <linux/miscdevice.h>32#include <linux/moduleparam.h>33#include <linux/virtio_mmio.h>34 35#include <asm/xen/hypervisor.h>36#include <asm/xen/hypercall.h>37 38#include <xen/xen.h>39#include <xen/events.h>40#include <xen/privcmd.h>41#include <xen/interface/xen.h>42#include <xen/interface/memory.h>43#include <xen/interface/hvm/dm_op.h>44#include <xen/interface/hvm/ioreq.h>45#include <xen/features.h>46#include <xen/page.h>47#include <xen/xen-ops.h>48#include <xen/balloon.h>49#ifdef CONFIG_XEN_ACPI50#include <xen/acpi.h>51#endif52 53#include "privcmd.h"54 55MODULE_DESCRIPTION("Xen hypercall passthrough driver");56MODULE_LICENSE("GPL");57 58#define PRIV_VMA_LOCKED ((void *)1)59 60static unsigned int privcmd_dm_op_max_num = 16;61module_param_named(dm_op_max_nr_bufs, privcmd_dm_op_max_num, uint, 0644);62MODULE_PARM_DESC(dm_op_max_nr_bufs,63 "Maximum number of buffers per dm_op hypercall");64 65static unsigned int privcmd_dm_op_buf_max_size = 4096;66module_param_named(dm_op_buf_max_size, privcmd_dm_op_buf_max_size, uint,67 0644);68MODULE_PARM_DESC(dm_op_buf_max_size,69 "Maximum size of a dm_op hypercall buffer");70 71struct privcmd_data {72 domid_t domid;73};74 75static int privcmd_vma_range_is_mapped(76 struct vm_area_struct *vma,77 unsigned long addr,78 unsigned long nr_pages);79 80static long privcmd_ioctl_hypercall(struct file *file, void __user *udata)81{82 struct privcmd_data *data = file->private_data;83 struct privcmd_hypercall hypercall;84 long ret;85 86 /* Disallow arbitrary hypercalls if restricted */87 if (data->domid != DOMID_INVALID)88 return -EPERM;89 90 if (copy_from_user(&hypercall, udata, sizeof(hypercall)))91 return -EFAULT;92 93 xen_preemptible_hcall_begin();94 ret = privcmd_call(hypercall.op,95 hypercall.arg[0], hypercall.arg[1],96 hypercall.arg[2], hypercall.arg[3],97 hypercall.arg[4]);98 xen_preemptible_hcall_end();99 100 return ret;101}102 103static void free_page_list(struct list_head *pages)104{105 struct page *p, *n;106 107 list_for_each_entry_safe(p, n, pages, lru)108 __free_page(p);109 110 INIT_LIST_HEAD(pages);111}112 113/*114 * Given an array of items in userspace, return a list of pages115 * containing the data. If copying fails, either because of memory116 * allocation failure or a problem reading user memory, return an117 * error code; its up to the caller to dispose of any partial list.118 */119static int gather_array(struct list_head *pagelist,120 unsigned nelem, size_t size,121 const void __user *data)122{123 unsigned pageidx;124 void *pagedata;125 int ret;126 127 if (size > PAGE_SIZE)128 return 0;129 130 pageidx = PAGE_SIZE;131 pagedata = NULL; /* quiet, gcc */132 while (nelem--) {133 if (pageidx > PAGE_SIZE-size) {134 struct page *page = alloc_page(GFP_KERNEL);135 136 ret = -ENOMEM;137 if (page == NULL)138 goto fail;139 140 pagedata = page_address(page);141 142 list_add_tail(&page->lru, pagelist);143 pageidx = 0;144 }145 146 ret = -EFAULT;147 if (copy_from_user(pagedata + pageidx, data, size))148 goto fail;149 150 data += size;151 pageidx += size;152 }153 154 ret = 0;155 156fail:157 return ret;158}159 160/*161 * Call function "fn" on each element of the array fragmented162 * over a list of pages.163 */164static int traverse_pages(unsigned nelem, size_t size,165 struct list_head *pos,166 int (*fn)(void *data, void *state),167 void *state)168{169 void *pagedata;170 unsigned pageidx;171 int ret = 0;172 173 BUG_ON(size > PAGE_SIZE);174 175 pageidx = PAGE_SIZE;176 pagedata = NULL; /* hush, gcc */177 178 while (nelem--) {179 if (pageidx > PAGE_SIZE-size) {180 struct page *page;181 pos = pos->next;182 page = list_entry(pos, struct page, lru);183 pagedata = page_address(page);184 pageidx = 0;185 }186 187 ret = (*fn)(pagedata + pageidx, state);188 if (ret)189 break;190 pageidx += size;191 }192 193 return ret;194}195 196/*197 * Similar to traverse_pages, but use each page as a "block" of198 * data to be processed as one unit.199 */200static int traverse_pages_block(unsigned nelem, size_t size,201 struct list_head *pos,202 int (*fn)(void *data, int nr, void *state),203 void *state)204{205 void *pagedata;206 int ret = 0;207 208 BUG_ON(size > PAGE_SIZE);209 210 while (nelem) {211 int nr = (PAGE_SIZE/size);212 struct page *page;213 if (nr > nelem)214 nr = nelem;215 pos = pos->next;216 page = list_entry(pos, struct page, lru);217 pagedata = page_address(page);218 ret = (*fn)(pagedata, nr, state);219 if (ret)220 break;221 nelem -= nr;222 }223 224 return ret;225}226 227struct mmap_gfn_state {228 unsigned long va;229 struct vm_area_struct *vma;230 domid_t domain;231};232 233static int mmap_gfn_range(void *data, void *state)234{235 struct privcmd_mmap_entry *msg = data;236 struct mmap_gfn_state *st = state;237 struct vm_area_struct *vma = st->vma;238 int rc;239 240 /* Do not allow range to wrap the address space. */241 if ((msg->npages > (LONG_MAX >> PAGE_SHIFT)) ||242 ((unsigned long)(msg->npages << PAGE_SHIFT) >= -st->va))243 return -EINVAL;244 245 /* Range chunks must be contiguous in va space. */246 if ((msg->va != st->va) ||247 ((msg->va+(msg->npages<<PAGE_SHIFT)) > vma->vm_end))248 return -EINVAL;249 250 rc = xen_remap_domain_gfn_range(vma,251 msg->va & PAGE_MASK,252 msg->mfn, msg->npages,253 vma->vm_page_prot,254 st->domain, NULL);255 if (rc < 0)256 return rc;257 258 st->va += msg->npages << PAGE_SHIFT;259 260 return 0;261}262 263static long privcmd_ioctl_mmap(struct file *file, void __user *udata)264{265 struct privcmd_data *data = file->private_data;266 struct privcmd_mmap mmapcmd;267 struct mm_struct *mm = current->mm;268 struct vm_area_struct *vma;269 int rc;270 LIST_HEAD(pagelist);271 struct mmap_gfn_state state;272 273 /* We only support privcmd_ioctl_mmap_batch for non-auto-translated. */274 if (xen_feature(XENFEAT_auto_translated_physmap))275 return -ENOSYS;276 277 if (copy_from_user(&mmapcmd, udata, sizeof(mmapcmd)))278 return -EFAULT;279 280 /* If restriction is in place, check the domid matches */281 if (data->domid != DOMID_INVALID && data->domid != mmapcmd.dom)282 return -EPERM;283 284 rc = gather_array(&pagelist,285 mmapcmd.num, sizeof(struct privcmd_mmap_entry),286 mmapcmd.entry);287 288 if (rc || list_empty(&pagelist))289 goto out;290 291 mmap_write_lock(mm);292 293 {294 struct page *page = list_first_entry(&pagelist,295 struct page, lru);296 struct privcmd_mmap_entry *msg = page_address(page);297 298 vma = vma_lookup(mm, msg->va);299 rc = -EINVAL;300 301 if (!vma || (msg->va != vma->vm_start) || vma->vm_private_data)302 goto out_up;303 vma->vm_private_data = PRIV_VMA_LOCKED;304 }305 306 state.va = vma->vm_start;307 state.vma = vma;308 state.domain = mmapcmd.dom;309 310 rc = traverse_pages(mmapcmd.num, sizeof(struct privcmd_mmap_entry),311 &pagelist,312 mmap_gfn_range, &state);313 314 315out_up:316 mmap_write_unlock(mm);317 318out:319 free_page_list(&pagelist);320 321 return rc;322}323 324struct mmap_batch_state {325 domid_t domain;326 unsigned long va;327 struct vm_area_struct *vma;328 int index;329 /* A tristate:330 * 0 for no errors331 * 1 if at least one error has happened (and no332 * -ENOENT errors have happened)333 * -ENOENT if at least 1 -ENOENT has happened.334 */335 int global_error;336 int version;337 338 /* User-space gfn array to store errors in the second pass for V1. */339 xen_pfn_t __user *user_gfn;340 /* User-space int array to store errors in the second pass for V2. */341 int __user *user_err;342};343 344/* auto translated dom0 note: if domU being created is PV, then gfn is345 * mfn(addr on bus). If it's auto xlated, then gfn is pfn (input to HAP).346 */347static int mmap_batch_fn(void *data, int nr, void *state)348{349 xen_pfn_t *gfnp = data;350 struct mmap_batch_state *st = state;351 struct vm_area_struct *vma = st->vma;352 struct page **pages = vma->vm_private_data;353 struct page **cur_pages = NULL;354 int ret;355 356 if (xen_feature(XENFEAT_auto_translated_physmap))357 cur_pages = &pages[st->index];358 359 BUG_ON(nr < 0);360 ret = xen_remap_domain_gfn_array(st->vma, st->va & PAGE_MASK, gfnp, nr,361 (int *)gfnp, st->vma->vm_page_prot,362 st->domain, cur_pages);363 364 /* Adjust the global_error? */365 if (ret != nr) {366 if (ret == -ENOENT)367 st->global_error = -ENOENT;368 else {369 /* Record that at least one error has happened. */370 if (st->global_error == 0)371 st->global_error = 1;372 }373 }374 st->va += XEN_PAGE_SIZE * nr;375 st->index += nr / XEN_PFN_PER_PAGE;376 377 return 0;378}379 380static int mmap_return_error(int err, struct mmap_batch_state *st)381{382 int ret;383 384 if (st->version == 1) {385 if (err) {386 xen_pfn_t gfn;387 388 ret = get_user(gfn, st->user_gfn);389 if (ret < 0)390 return ret;391 /*392 * V1 encodes the error codes in the 32bit top393 * nibble of the gfn (with its known394 * limitations vis-a-vis 64 bit callers).395 */396 gfn |= (err == -ENOENT) ?397 PRIVCMD_MMAPBATCH_PAGED_ERROR :398 PRIVCMD_MMAPBATCH_MFN_ERROR;399 return __put_user(gfn, st->user_gfn++);400 } else401 st->user_gfn++;402 } else { /* st->version == 2 */403 if (err)404 return __put_user(err, st->user_err++);405 else406 st->user_err++;407 }408 409 return 0;410}411 412static int mmap_return_errors(void *data, int nr, void *state)413{414 struct mmap_batch_state *st = state;415 int *errs = data;416 int i;417 int ret;418 419 for (i = 0; i < nr; i++) {420 ret = mmap_return_error(errs[i], st);421 if (ret < 0)422 return ret;423 }424 return 0;425}426 427/* Allocate pfns that are then mapped with gfns from foreign domid. Update428 * the vma with the page info to use later.429 * Returns: 0 if success, otherwise -errno430 */431static int alloc_empty_pages(struct vm_area_struct *vma, int numpgs)432{433 int rc;434 struct page **pages;435 436 pages = kvcalloc(numpgs, sizeof(pages[0]), GFP_KERNEL);437 if (pages == NULL)438 return -ENOMEM;439 440 rc = xen_alloc_unpopulated_pages(numpgs, pages);441 if (rc != 0) {442 pr_warn("%s Could not alloc %d pfns rc:%d\n", __func__,443 numpgs, rc);444 kvfree(pages);445 return -ENOMEM;446 }447 BUG_ON(vma->vm_private_data != NULL);448 vma->vm_private_data = pages;449 450 return 0;451}452 453static const struct vm_operations_struct privcmd_vm_ops;454 455static long privcmd_ioctl_mmap_batch(456 struct file *file, void __user *udata, int version)457{458 struct privcmd_data *data = file->private_data;459 int ret;460 struct privcmd_mmapbatch_v2 m;461 struct mm_struct *mm = current->mm;462 struct vm_area_struct *vma;463 unsigned long nr_pages;464 LIST_HEAD(pagelist);465 struct mmap_batch_state state;466 467 switch (version) {468 case 1:469 if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch)))470 return -EFAULT;471 /* Returns per-frame error in m.arr. */472 m.err = NULL;473 if (!access_ok(m.arr, m.num * sizeof(*m.arr)))474 return -EFAULT;475 break;476 case 2:477 if (copy_from_user(&m, udata, sizeof(struct privcmd_mmapbatch_v2)))478 return -EFAULT;479 /* Returns per-frame error code in m.err. */480 if (!access_ok(m.err, m.num * (sizeof(*m.err))))481 return -EFAULT;482 break;483 default:484 return -EINVAL;485 }486 487 /* If restriction is in place, check the domid matches */488 if (data->domid != DOMID_INVALID && data->domid != m.dom)489 return -EPERM;490 491 nr_pages = DIV_ROUND_UP(m.num, XEN_PFN_PER_PAGE);492 if ((m.num <= 0) || (nr_pages > (LONG_MAX >> PAGE_SHIFT)))493 return -EINVAL;494 495 ret = gather_array(&pagelist, m.num, sizeof(xen_pfn_t), m.arr);496 497 if (ret)498 goto out;499 if (list_empty(&pagelist)) {500 ret = -EINVAL;501 goto out;502 }503 504 if (version == 2) {505 /* Zero error array now to only copy back actual errors. */506 if (clear_user(m.err, sizeof(int) * m.num)) {507 ret = -EFAULT;508 goto out;509 }510 }511 512 mmap_write_lock(mm);513 514 vma = find_vma(mm, m.addr);515 if (!vma ||516 vma->vm_ops != &privcmd_vm_ops) {517 ret = -EINVAL;518 goto out_unlock;519 }520 521 /*522 * Caller must either:523 *524 * Map the whole VMA range, which will also allocate all the525 * pages required for the auto_translated_physmap case.526 *527 * Or528 *529 * Map unmapped holes left from a previous map attempt (e.g.,530 * because those foreign frames were previously paged out).531 */532 if (vma->vm_private_data == NULL) {533 if (m.addr != vma->vm_start ||534 m.addr + (nr_pages << PAGE_SHIFT) != vma->vm_end) {535 ret = -EINVAL;536 goto out_unlock;537 }538 if (xen_feature(XENFEAT_auto_translated_physmap)) {539 ret = alloc_empty_pages(vma, nr_pages);540 if (ret < 0)541 goto out_unlock;542 } else543 vma->vm_private_data = PRIV_VMA_LOCKED;544 } else {545 if (m.addr < vma->vm_start ||546 m.addr + (nr_pages << PAGE_SHIFT) > vma->vm_end) {547 ret = -EINVAL;548 goto out_unlock;549 }550 if (privcmd_vma_range_is_mapped(vma, m.addr, nr_pages)) {551 ret = -EINVAL;552 goto out_unlock;553 }554 }555 556 state.domain = m.dom;557 state.vma = vma;558 state.va = m.addr;559 state.index = 0;560 state.global_error = 0;561 state.version = version;562 563 BUILD_BUG_ON(((PAGE_SIZE / sizeof(xen_pfn_t)) % XEN_PFN_PER_PAGE) != 0);564 /* mmap_batch_fn guarantees ret == 0 */565 BUG_ON(traverse_pages_block(m.num, sizeof(xen_pfn_t),566 &pagelist, mmap_batch_fn, &state));567 568 mmap_write_unlock(mm);569 570 if (state.global_error) {571 /* Write back errors in second pass. */572 state.user_gfn = (xen_pfn_t *)m.arr;573 state.user_err = m.err;574 ret = traverse_pages_block(m.num, sizeof(xen_pfn_t),575 &pagelist, mmap_return_errors, &state);576 } else577 ret = 0;578 579 /* If we have not had any EFAULT-like global errors then set the global580 * error to -ENOENT if necessary. */581 if ((ret == 0) && (state.global_error == -ENOENT))582 ret = -ENOENT;583 584out:585 free_page_list(&pagelist);586 return ret;587 588out_unlock:589 mmap_write_unlock(mm);590 goto out;591}592 593static int lock_pages(594 struct privcmd_dm_op_buf kbufs[], unsigned int num,595 struct page *pages[], unsigned int nr_pages, unsigned int *pinned)596{597 unsigned int i, off = 0;598 599 for (i = 0; i < num; ) {600 unsigned int requested;601 int page_count;602 603 requested = DIV_ROUND_UP(604 offset_in_page(kbufs[i].uptr) + kbufs[i].size,605 PAGE_SIZE) - off;606 if (requested > nr_pages)607 return -ENOSPC;608 609 page_count = pin_user_pages_fast(610 (unsigned long)kbufs[i].uptr + off * PAGE_SIZE,611 requested, FOLL_WRITE, pages);612 if (page_count <= 0)613 return page_count ? : -EFAULT;614 615 *pinned += page_count;616 nr_pages -= page_count;617 pages += page_count;618 619 off = (requested == page_count) ? 0 : off + page_count;620 i += !off;621 }622 623 return 0;624}625 626static void unlock_pages(struct page *pages[], unsigned int nr_pages)627{628 unpin_user_pages_dirty_lock(pages, nr_pages, true);629}630 631static long privcmd_ioctl_dm_op(struct file *file, void __user *udata)632{633 struct privcmd_data *data = file->private_data;634 struct privcmd_dm_op kdata;635 struct privcmd_dm_op_buf *kbufs;636 unsigned int nr_pages = 0;637 struct page **pages = NULL;638 struct xen_dm_op_buf *xbufs = NULL;639 unsigned int i;640 long rc;641 unsigned int pinned = 0;642 643 if (copy_from_user(&kdata, udata, sizeof(kdata)))644 return -EFAULT;645 646 /* If restriction is in place, check the domid matches */647 if (data->domid != DOMID_INVALID && data->domid != kdata.dom)648 return -EPERM;649 650 if (kdata.num == 0)651 return 0;652 653 if (kdata.num > privcmd_dm_op_max_num)654 return -E2BIG;655 656 kbufs = kcalloc(kdata.num, sizeof(*kbufs), GFP_KERNEL);657 if (!kbufs)658 return -ENOMEM;659 660 if (copy_from_user(kbufs, kdata.ubufs,661 sizeof(*kbufs) * kdata.num)) {662 rc = -EFAULT;663 goto out;664 }665 666 for (i = 0; i < kdata.num; i++) {667 if (kbufs[i].size > privcmd_dm_op_buf_max_size) {668 rc = -E2BIG;669 goto out;670 }671 672 if (!access_ok(kbufs[i].uptr,673 kbufs[i].size)) {674 rc = -EFAULT;675 goto out;676 }677 678 nr_pages += DIV_ROUND_UP(679 offset_in_page(kbufs[i].uptr) + kbufs[i].size,680 PAGE_SIZE);681 }682 683 pages = kcalloc(nr_pages, sizeof(*pages), GFP_KERNEL);684 if (!pages) {685 rc = -ENOMEM;686 goto out;687 }688 689 xbufs = kcalloc(kdata.num, sizeof(*xbufs), GFP_KERNEL);690 if (!xbufs) {691 rc = -ENOMEM;692 goto out;693 }694 695 rc = lock_pages(kbufs, kdata.num, pages, nr_pages, &pinned);696 if (rc < 0)697 goto out;698 699 for (i = 0; i < kdata.num; i++) {700 set_xen_guest_handle(xbufs[i].h, kbufs[i].uptr);701 xbufs[i].size = kbufs[i].size;702 }703 704 xen_preemptible_hcall_begin();705 rc = HYPERVISOR_dm_op(kdata.dom, kdata.num, xbufs);706 xen_preemptible_hcall_end();707 708out:709 unlock_pages(pages, pinned);710 kfree(xbufs);711 kfree(pages);712 kfree(kbufs);713 714 return rc;715}716 717static long privcmd_ioctl_restrict(struct file *file, void __user *udata)718{719 struct privcmd_data *data = file->private_data;720 domid_t dom;721 722 if (copy_from_user(&dom, udata, sizeof(dom)))723 return -EFAULT;724 725 /* Set restriction to the specified domain, or check it matches */726 if (data->domid == DOMID_INVALID)727 data->domid = dom;728 else if (data->domid != dom)729 return -EINVAL;730 731 return 0;732}733 734static long privcmd_ioctl_mmap_resource(struct file *file,735 struct privcmd_mmap_resource __user *udata)736{737 struct privcmd_data *data = file->private_data;738 struct mm_struct *mm = current->mm;739 struct vm_area_struct *vma;740 struct privcmd_mmap_resource kdata;741 xen_pfn_t *pfns = NULL;742 struct xen_mem_acquire_resource xdata = { };743 int rc;744 745 if (copy_from_user(&kdata, udata, sizeof(kdata)))746 return -EFAULT;747 748 /* If restriction is in place, check the domid matches */749 if (data->domid != DOMID_INVALID && data->domid != kdata.dom)750 return -EPERM;751 752 /* Both fields must be set or unset */753 if (!!kdata.addr != !!kdata.num)754 return -EINVAL;755 756 xdata.domid = kdata.dom;757 xdata.type = kdata.type;758 xdata.id = kdata.id;759 760 if (!kdata.addr && !kdata.num) {761 /* Query the size of the resource. */762 rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);763 if (rc)764 return rc;765 return __put_user(xdata.nr_frames, &udata->num);766 }767 768 mmap_write_lock(mm);769 770 vma = find_vma(mm, kdata.addr);771 if (!vma || vma->vm_ops != &privcmd_vm_ops) {772 rc = -EINVAL;773 goto out;774 }775 776 pfns = kcalloc(kdata.num, sizeof(*pfns), GFP_KERNEL | __GFP_NOWARN);777 if (!pfns) {778 rc = -ENOMEM;779 goto out;780 }781 782 if (IS_ENABLED(CONFIG_XEN_AUTO_XLATE) &&783 xen_feature(XENFEAT_auto_translated_physmap)) {784 unsigned int nr = DIV_ROUND_UP(kdata.num, XEN_PFN_PER_PAGE);785 struct page **pages;786 unsigned int i;787 788 rc = alloc_empty_pages(vma, nr);789 if (rc < 0)790 goto out;791 792 pages = vma->vm_private_data;793 794 for (i = 0; i < kdata.num; i++) {795 xen_pfn_t pfn =796 page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]);797 798 pfns[i] = pfn + (i % XEN_PFN_PER_PAGE);799 }800 } else801 vma->vm_private_data = PRIV_VMA_LOCKED;802 803 xdata.frame = kdata.idx;804 xdata.nr_frames = kdata.num;805 set_xen_guest_handle(xdata.frame_list, pfns);806 807 xen_preemptible_hcall_begin();808 rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);809 xen_preemptible_hcall_end();810 811 if (rc)812 goto out;813 814 if (IS_ENABLED(CONFIG_XEN_AUTO_XLATE) &&815 xen_feature(XENFEAT_auto_translated_physmap)) {816 rc = xen_remap_vma_range(vma, kdata.addr, kdata.num << PAGE_SHIFT);817 } else {818 unsigned int domid =819 (xdata.flags & XENMEM_rsrc_acq_caller_owned) ?820 DOMID_SELF : kdata.dom;821 int num, *errs = (int *)pfns;822 823 BUILD_BUG_ON(sizeof(*errs) > sizeof(*pfns));824 num = xen_remap_domain_mfn_array(vma,825 kdata.addr & PAGE_MASK,826 pfns, kdata.num, errs,827 vma->vm_page_prot,828 domid);829 if (num < 0)830 rc = num;831 else if (num != kdata.num) {832 unsigned int i;833 834 for (i = 0; i < num; i++) {835 rc = errs[i];836 if (rc < 0)837 break;838 }839 } else840 rc = 0;841 }842 843out:844 mmap_write_unlock(mm);845 kfree(pfns);846 847 return rc;848}849 850static long privcmd_ioctl_pcidev_get_gsi(struct file *file, void __user *udata)851{852#if defined(CONFIG_XEN_ACPI)853 int rc;854 struct privcmd_pcidev_get_gsi kdata;855 856 if (copy_from_user(&kdata, udata, sizeof(kdata)))857 return -EFAULT;858 859 rc = xen_acpi_get_gsi_from_sbdf(kdata.sbdf);860 if (rc < 0)861 return rc;862 863 kdata.gsi = rc;864 if (copy_to_user(udata, &kdata, sizeof(kdata)))865 return -EFAULT;866 867 return 0;868#else869 return -EINVAL;870#endif871}872 873#ifdef CONFIG_XEN_PRIVCMD_EVENTFD874/* Irqfd support */875static struct workqueue_struct *irqfd_cleanup_wq;876static DEFINE_SPINLOCK(irqfds_lock);877DEFINE_STATIC_SRCU(irqfds_srcu);878static LIST_HEAD(irqfds_list);879 880struct privcmd_kernel_irqfd {881 struct xen_dm_op_buf xbufs;882 domid_t dom;883 bool error;884 struct eventfd_ctx *eventfd;885 struct work_struct shutdown;886 wait_queue_entry_t wait;887 struct list_head list;888 poll_table pt;889};890 891static void irqfd_deactivate(struct privcmd_kernel_irqfd *kirqfd)892{893 lockdep_assert_held(&irqfds_lock);894 895 list_del_init(&kirqfd->list);896 queue_work(irqfd_cleanup_wq, &kirqfd->shutdown);897}898 899static void irqfd_shutdown(struct work_struct *work)900{901 struct privcmd_kernel_irqfd *kirqfd =902 container_of(work, struct privcmd_kernel_irqfd, shutdown);903 u64 cnt;904 905 /* Make sure irqfd has been initialized in assign path */906 synchronize_srcu(&irqfds_srcu);907 908 eventfd_ctx_remove_wait_queue(kirqfd->eventfd, &kirqfd->wait, &cnt);909 eventfd_ctx_put(kirqfd->eventfd);910 kfree(kirqfd);911}912 913static void irqfd_inject(struct privcmd_kernel_irqfd *kirqfd)914{915 u64 cnt;916 long rc;917 918 eventfd_ctx_do_read(kirqfd->eventfd, &cnt);919 920 xen_preemptible_hcall_begin();921 rc = HYPERVISOR_dm_op(kirqfd->dom, 1, &kirqfd->xbufs);922 xen_preemptible_hcall_end();923 924 /* Don't repeat the error message for consecutive failures */925 if (rc && !kirqfd->error) {926 pr_err("Failed to configure irq for guest domain: %d\n",927 kirqfd->dom);928 }929 930 kirqfd->error = rc;931}932 933static int934irqfd_wakeup(wait_queue_entry_t *wait, unsigned int mode, int sync, void *key)935{936 struct privcmd_kernel_irqfd *kirqfd =937 container_of(wait, struct privcmd_kernel_irqfd, wait);938 __poll_t flags = key_to_poll(key);939 940 if (flags & EPOLLIN)941 irqfd_inject(kirqfd);942 943 if (flags & EPOLLHUP) {944 unsigned long flags;945 946 spin_lock_irqsave(&irqfds_lock, flags);947 irqfd_deactivate(kirqfd);948 spin_unlock_irqrestore(&irqfds_lock, flags);949 }950 951 return 0;952}953 954static void955irqfd_poll_func(struct file *file, wait_queue_head_t *wqh, poll_table *pt)956{957 struct privcmd_kernel_irqfd *kirqfd =958 container_of(pt, struct privcmd_kernel_irqfd, pt);959 960 add_wait_queue_priority(wqh, &kirqfd->wait);961}962 963static int privcmd_irqfd_assign(struct privcmd_irqfd *irqfd)964{965 struct privcmd_kernel_irqfd *kirqfd, *tmp;966 unsigned long flags;967 __poll_t events;968 struct fd f;969 void *dm_op;970 int ret, idx;971 972 kirqfd = kzalloc(sizeof(*kirqfd) + irqfd->size, GFP_KERNEL);973 if (!kirqfd)974 return -ENOMEM;975 dm_op = kirqfd + 1;976 977 if (copy_from_user(dm_op, u64_to_user_ptr(irqfd->dm_op), irqfd->size)) {978 ret = -EFAULT;979 goto error_kfree;980 }981 982 kirqfd->xbufs.size = irqfd->size;983 set_xen_guest_handle(kirqfd->xbufs.h, dm_op);984 kirqfd->dom = irqfd->dom;985 INIT_WORK(&kirqfd->shutdown, irqfd_shutdown);986 987 f = fdget(irqfd->fd);988 if (!fd_file(f)) {989 ret = -EBADF;990 goto error_kfree;991 }992 993 kirqfd->eventfd = eventfd_ctx_fileget(fd_file(f));994 if (IS_ERR(kirqfd->eventfd)) {995 ret = PTR_ERR(kirqfd->eventfd);996 goto error_fd_put;997 }998 999 /*1000 * Install our own custom wake-up handling so we are notified via a1001 * callback whenever someone signals the underlying eventfd.1002 */1003 init_waitqueue_func_entry(&kirqfd->wait, irqfd_wakeup);1004 init_poll_funcptr(&kirqfd->pt, irqfd_poll_func);1005 1006 spin_lock_irqsave(&irqfds_lock, flags);1007 1008 list_for_each_entry(tmp, &irqfds_list, list) {1009 if (kirqfd->eventfd == tmp->eventfd) {1010 ret = -EBUSY;1011 spin_unlock_irqrestore(&irqfds_lock, flags);1012 goto error_eventfd;1013 }1014 }1015 1016 idx = srcu_read_lock(&irqfds_srcu);1017 list_add_tail(&kirqfd->list, &irqfds_list);1018 spin_unlock_irqrestore(&irqfds_lock, flags);1019 1020 /*1021 * Check if there was an event already pending on the eventfd before we1022 * registered, and trigger it as if we didn't miss it.1023 */1024 events = vfs_poll(fd_file(f), &kirqfd->pt);1025 if (events & EPOLLIN)1026 irqfd_inject(kirqfd);1027 1028 srcu_read_unlock(&irqfds_srcu, idx);1029 1030 /*1031 * Do not drop the file until the kirqfd is fully initialized, otherwise1032 * we might race against the EPOLLHUP.1033 */1034 fdput(f);1035 return 0;1036 1037error_eventfd:1038 eventfd_ctx_put(kirqfd->eventfd);1039 1040error_fd_put:1041 fdput(f);1042 1043error_kfree:1044 kfree(kirqfd);1045 return ret;1046}1047 1048static int privcmd_irqfd_deassign(struct privcmd_irqfd *irqfd)1049{1050 struct privcmd_kernel_irqfd *kirqfd;1051 struct eventfd_ctx *eventfd;1052 unsigned long flags;1053 1054 eventfd = eventfd_ctx_fdget(irqfd->fd);1055 if (IS_ERR(eventfd))1056 return PTR_ERR(eventfd);1057 1058 spin_lock_irqsave(&irqfds_lock, flags);1059 1060 list_for_each_entry(kirqfd, &irqfds_list, list) {1061 if (kirqfd->eventfd == eventfd) {1062 irqfd_deactivate(kirqfd);1063 break;1064 }1065 }1066 1067 spin_unlock_irqrestore(&irqfds_lock, flags);1068 1069 eventfd_ctx_put(eventfd);1070 1071 /*1072 * Block until we know all outstanding shutdown jobs have completed so1073 * that we guarantee there will not be any more interrupts once this1074 * deassign function returns.1075 */1076 flush_workqueue(irqfd_cleanup_wq);1077 1078 return 0;1079}1080 1081static long privcmd_ioctl_irqfd(struct file *file, void __user *udata)1082{1083 struct privcmd_data *data = file->private_data;1084 struct privcmd_irqfd irqfd;1085 1086 if (copy_from_user(&irqfd, udata, sizeof(irqfd)))1087 return -EFAULT;1088 1089 /* No other flags should be set */1090 if (irqfd.flags & ~PRIVCMD_IRQFD_FLAG_DEASSIGN)1091 return -EINVAL;1092 1093 /* If restriction is in place, check the domid matches */1094 if (data->domid != DOMID_INVALID && data->domid != irqfd.dom)1095 return -EPERM;1096 1097 if (irqfd.flags & PRIVCMD_IRQFD_FLAG_DEASSIGN)1098 return privcmd_irqfd_deassign(&irqfd);1099 1100 return privcmd_irqfd_assign(&irqfd);1101}1102 1103static int privcmd_irqfd_init(void)1104{1105 irqfd_cleanup_wq = alloc_workqueue("privcmd-irqfd-cleanup", 0, 0);1106 if (!irqfd_cleanup_wq)1107 return -ENOMEM;1108 1109 return 0;1110}1111 1112static void privcmd_irqfd_exit(void)1113{1114 struct privcmd_kernel_irqfd *kirqfd, *tmp;1115 unsigned long flags;1116 1117 spin_lock_irqsave(&irqfds_lock, flags);1118 1119 list_for_each_entry_safe(kirqfd, tmp, &irqfds_list, list)1120 irqfd_deactivate(kirqfd);1121 1122 spin_unlock_irqrestore(&irqfds_lock, flags);1123 1124 destroy_workqueue(irqfd_cleanup_wq);1125}1126 1127/* Ioeventfd Support */1128#define QUEUE_NOTIFY_VQ_MASK 0xFFFF1129 1130static DEFINE_MUTEX(ioreq_lock);1131static LIST_HEAD(ioreq_list);1132 1133/* per-eventfd structure */1134struct privcmd_kernel_ioeventfd {1135 struct eventfd_ctx *eventfd;1136 struct list_head list;1137 u64 addr;1138 unsigned int addr_len;1139 unsigned int vq;1140};1141 1142/* per-guest CPU / port structure */1143struct ioreq_port {1144 int vcpu;1145 unsigned int port;1146 struct privcmd_kernel_ioreq *kioreq;1147};1148 1149/* per-guest structure */1150struct privcmd_kernel_ioreq {1151 domid_t dom;1152 unsigned int vcpus;1153 u64 uioreq;1154 struct ioreq *ioreq;1155 spinlock_t lock; /* Protects ioeventfds list */1156 struct list_head ioeventfds;1157 struct list_head list;1158 struct ioreq_port ports[] __counted_by(vcpus);1159};1160 1161static irqreturn_t ioeventfd_interrupt(int irq, void *dev_id)1162{1163 struct ioreq_port *port = dev_id;1164 struct privcmd_kernel_ioreq *kioreq = port->kioreq;1165 struct ioreq *ioreq = &kioreq->ioreq[port->vcpu];1166 struct privcmd_kernel_ioeventfd *kioeventfd;1167 unsigned int state = STATE_IOREQ_READY;1168 1169 if (ioreq->state != STATE_IOREQ_READY ||1170 ioreq->type != IOREQ_TYPE_COPY || ioreq->dir != IOREQ_WRITE)1171 return IRQ_NONE;1172 1173 /*1174 * We need a barrier, smp_mb(), here to ensure reads are finished before1175 * `state` is updated. Since the lock implementation ensures that1176 * appropriate barrier will be added anyway, we can avoid adding1177 * explicit barrier here.1178 *1179 * Ideally we don't need to update `state` within the locks, but we do1180 * that here to avoid adding explicit barrier.1181 */1182 1183 spin_lock(&kioreq->lock);1184 ioreq->state = STATE_IOREQ_INPROCESS;1185 1186 list_for_each_entry(kioeventfd, &kioreq->ioeventfds, list) {1187 if (ioreq->addr == kioeventfd->addr + VIRTIO_MMIO_QUEUE_NOTIFY &&1188 ioreq->size == kioeventfd->addr_len &&1189 (ioreq->data & QUEUE_NOTIFY_VQ_MASK) == kioeventfd->vq) {1190 eventfd_signal(kioeventfd->eventfd);1191 state = STATE_IORESP_READY;1192 break;1193 }1194 }1195 spin_unlock(&kioreq->lock);1196 1197 /*1198 * We need a barrier, smp_mb(), here to ensure writes are finished1199 * before `state` is updated. Since the lock implementation ensures that1200 * appropriate barrier will be added anyway, we can avoid adding1201 * explicit barrier here.1202 */1203 1204 ioreq->state = state;1205 1206 if (state == STATE_IORESP_READY) {1207 notify_remote_via_evtchn(port->port);1208 return IRQ_HANDLED;1209 }1210 1211 return IRQ_NONE;1212}1213 1214static void ioreq_free(struct privcmd_kernel_ioreq *kioreq)1215{1216 struct ioreq_port *ports = kioreq->ports;1217 int i;1218 1219 lockdep_assert_held(&ioreq_lock);1220 1221 list_del(&kioreq->list);1222 1223 for (i = kioreq->vcpus - 1; i >= 0; i--)1224 unbind_from_irqhandler(irq_from_evtchn(ports[i].port), &ports[i]);1225 1226 kfree(kioreq);1227}1228 1229static1230struct privcmd_kernel_ioreq *alloc_ioreq(struct privcmd_ioeventfd *ioeventfd)1231{1232 struct privcmd_kernel_ioreq *kioreq;1233 struct mm_struct *mm = current->mm;1234 struct vm_area_struct *vma;1235 struct page **pages;1236 unsigned int *ports;1237 int ret, size, i;1238 1239 lockdep_assert_held(&ioreq_lock);1240 1241 size = struct_size(kioreq, ports, ioeventfd->vcpus);1242 kioreq = kzalloc(size, GFP_KERNEL);1243 if (!kioreq)1244 return ERR_PTR(-ENOMEM);1245 1246 kioreq->dom = ioeventfd->dom;1247 kioreq->vcpus = ioeventfd->vcpus;1248 kioreq->uioreq = ioeventfd->ioreq;1249 spin_lock_init(&kioreq->lock);1250 INIT_LIST_HEAD(&kioreq->ioeventfds);1251 1252 /* The memory for ioreq server must have been mapped earlier */1253 mmap_write_lock(mm);1254 vma = find_vma(mm, (unsigned long)ioeventfd->ioreq);1255 if (!vma) {1256 pr_err("Failed to find vma for ioreq page!\n");1257 mmap_write_unlock(mm);1258 ret = -EFAULT;1259 goto error_kfree;1260 }1261 1262 pages = vma->vm_private_data;1263 kioreq->ioreq = (struct ioreq *)(page_to_virt(pages[0]));1264 mmap_write_unlock(mm);1265 1266 ports = memdup_array_user(u64_to_user_ptr(ioeventfd->ports),1267 kioreq->vcpus, sizeof(*ports));1268 if (IS_ERR(ports)) {1269 ret = PTR_ERR(ports);1270 goto error_kfree;1271 }1272 1273 for (i = 0; i < kioreq->vcpus; i++) {1274 kioreq->ports[i].vcpu = i;1275 kioreq->ports[i].port = ports[i];1276 kioreq->ports[i].kioreq = kioreq;1277 1278 ret = bind_evtchn_to_irqhandler_lateeoi(ports[i],1279 ioeventfd_interrupt, IRQF_SHARED, "ioeventfd",1280 &kioreq->ports[i]);1281 if (ret < 0)1282 goto error_unbind;1283 }1284 1285 kfree(ports);1286 1287 list_add_tail(&kioreq->list, &ioreq_list);1288 1289 return kioreq;1290 1291error_unbind:1292 while (--i >= 0)1293 unbind_from_irqhandler(irq_from_evtchn(ports[i]), &kioreq->ports[i]);1294 1295 kfree(ports);1296error_kfree:1297 kfree(kioreq);1298 return ERR_PTR(ret);1299}1300 1301static struct privcmd_kernel_ioreq *1302get_ioreq(struct privcmd_ioeventfd *ioeventfd, struct eventfd_ctx *eventfd)1303{1304 struct privcmd_kernel_ioreq *kioreq;1305 unsigned long flags;1306 1307 list_for_each_entry(kioreq, &ioreq_list, list) {1308 struct privcmd_kernel_ioeventfd *kioeventfd;1309 1310 /*1311 * kioreq fields can be accessed here without a lock as they are1312 * never updated after being added to the ioreq_list.1313 */1314 if (kioreq->uioreq != ioeventfd->ioreq) {1315 continue;1316 } else if (kioreq->dom != ioeventfd->dom ||1317 kioreq->vcpus != ioeventfd->vcpus) {1318 pr_err("Invalid ioeventfd configuration mismatch, dom (%u vs %u), vcpus (%u vs %u)\n",1319 kioreq->dom, ioeventfd->dom, kioreq->vcpus,1320 ioeventfd->vcpus);1321 return ERR_PTR(-EINVAL);1322 }1323 1324 /* Look for a duplicate eventfd for the same guest */1325 spin_lock_irqsave(&kioreq->lock, flags);1326 list_for_each_entry(kioeventfd, &kioreq->ioeventfds, list) {1327 if (eventfd == kioeventfd->eventfd) {1328 spin_unlock_irqrestore(&kioreq->lock, flags);1329 return ERR_PTR(-EBUSY);1330 }1331 }1332 spin_unlock_irqrestore(&kioreq->lock, flags);1333 1334 return kioreq;1335 }1336 1337 /* Matching kioreq isn't found, allocate a new one */1338 return alloc_ioreq(ioeventfd);1339}1340 1341static void ioeventfd_free(struct privcmd_kernel_ioeventfd *kioeventfd)1342{1343 list_del(&kioeventfd->list);1344 eventfd_ctx_put(kioeventfd->eventfd);1345 kfree(kioeventfd);1346}1347 1348static int privcmd_ioeventfd_assign(struct privcmd_ioeventfd *ioeventfd)1349{1350 struct privcmd_kernel_ioeventfd *kioeventfd;1351 struct privcmd_kernel_ioreq *kioreq;1352 unsigned long flags;1353 struct fd f;1354 int ret;1355 1356 /* Check for range overflow */1357 if (ioeventfd->addr + ioeventfd->addr_len < ioeventfd->addr)1358 return -EINVAL;1359 1360 /* Vhost requires us to support length 1, 2, 4, and 8 */1361 if (!(ioeventfd->addr_len == 1 || ioeventfd->addr_len == 2 ||1362 ioeventfd->addr_len == 4 || ioeventfd->addr_len == 8))1363 return -EINVAL;1364 1365 /* 4096 vcpus limit enough ? */1366 if (!ioeventfd->vcpus || ioeventfd->vcpus > 4096)1367 return -EINVAL;1368 1369 kioeventfd = kzalloc(sizeof(*kioeventfd), GFP_KERNEL);1370 if (!kioeventfd)1371 return -ENOMEM;1372 1373 f = fdget(ioeventfd->event_fd);1374 if (!fd_file(f)) {1375 ret = -EBADF;1376 goto error_kfree;1377 }1378 1379 kioeventfd->eventfd = eventfd_ctx_fileget(fd_file(f));1380 fdput(f);1381 1382 if (IS_ERR(kioeventfd->eventfd)) {1383 ret = PTR_ERR(kioeventfd->eventfd);1384 goto error_kfree;1385 }1386 1387 kioeventfd->addr = ioeventfd->addr;1388 kioeventfd->addr_len = ioeventfd->addr_len;1389 kioeventfd->vq = ioeventfd->vq;1390 1391 mutex_lock(&ioreq_lock);1392 kioreq = get_ioreq(ioeventfd, kioeventfd->eventfd);1393 if (IS_ERR(kioreq)) {1394 mutex_unlock(&ioreq_lock);1395 ret = PTR_ERR(kioreq);1396 goto error_eventfd;1397 }1398 1399 spin_lock_irqsave(&kioreq->lock, flags);1400 list_add_tail(&kioeventfd->list, &kioreq->ioeventfds);1401 spin_unlock_irqrestore(&kioreq->lock, flags);1402 1403 mutex_unlock(&ioreq_lock);1404 1405 return 0;1406 1407error_eventfd:1408 eventfd_ctx_put(kioeventfd->eventfd);1409 1410error_kfree:1411 kfree(kioeventfd);1412 return ret;1413}1414 1415static int privcmd_ioeventfd_deassign(struct privcmd_ioeventfd *ioeventfd)1416{1417 struct privcmd_kernel_ioreq *kioreq, *tkioreq;1418 struct eventfd_ctx *eventfd;1419 unsigned long flags;1420 int ret = 0;1421 1422 eventfd = eventfd_ctx_fdget(ioeventfd->event_fd);1423 if (IS_ERR(eventfd))1424 return PTR_ERR(eventfd);1425 1426 mutex_lock(&ioreq_lock);1427 list_for_each_entry_safe(kioreq, tkioreq, &ioreq_list, list) {1428 struct privcmd_kernel_ioeventfd *kioeventfd, *tmp;1429 /*1430 * kioreq fields can be accessed here without a lock as they are1431 * never updated after being added to the ioreq_list.1432 */1433 if (kioreq->dom != ioeventfd->dom ||1434 kioreq->uioreq != ioeventfd->ioreq ||1435 kioreq->vcpus != ioeventfd->vcpus)1436 continue;1437 1438 spin_lock_irqsave(&kioreq->lock, flags);1439 list_for_each_entry_safe(kioeventfd, tmp, &kioreq->ioeventfds, list) {1440 if (eventfd == kioeventfd->eventfd) {1441 ioeventfd_free(kioeventfd);1442 spin_unlock_irqrestore(&kioreq->lock, flags);1443 1444 if (list_empty(&kioreq->ioeventfds))1445 ioreq_free(kioreq);1446 goto unlock;1447 }1448 }1449 spin_unlock_irqrestore(&kioreq->lock, flags);1450 break;1451 }1452 1453 pr_err("Ioeventfd isn't already assigned, dom: %u, addr: %llu\n",1454 ioeventfd->dom, ioeventfd->addr);1455 ret = -ENODEV;1456 1457unlock:1458 mutex_unlock(&ioreq_lock);1459 eventfd_ctx_put(eventfd);1460 1461 return ret;1462}1463 1464static long privcmd_ioctl_ioeventfd(struct file *file, void __user *udata)1465{1466 struct privcmd_data *data = file->private_data;1467 struct privcmd_ioeventfd ioeventfd;1468 1469 if (copy_from_user(&ioeventfd, udata, sizeof(ioeventfd)))1470 return -EFAULT;1471 1472 /* No other flags should be set */1473 if (ioeventfd.flags & ~PRIVCMD_IOEVENTFD_FLAG_DEASSIGN)1474 return -EINVAL;1475 1476 /* If restriction is in place, check the domid matches */1477 if (data->domid != DOMID_INVALID && data->domid != ioeventfd.dom)1478 return -EPERM;1479 1480 if (ioeventfd.flags & PRIVCMD_IOEVENTFD_FLAG_DEASSIGN)1481 return privcmd_ioeventfd_deassign(&ioeventfd);1482 1483 return privcmd_ioeventfd_assign(&ioeventfd);1484}1485 1486static void privcmd_ioeventfd_exit(void)1487{1488 struct privcmd_kernel_ioreq *kioreq, *tmp;1489 unsigned long flags;1490 1491 mutex_lock(&ioreq_lock);1492 list_for_each_entry_safe(kioreq, tmp, &ioreq_list, list) {1493 struct privcmd_kernel_ioeventfd *kioeventfd, *tmp;1494 1495 spin_lock_irqsave(&kioreq->lock, flags);1496 list_for_each_entry_safe(kioeventfd, tmp, &kioreq->ioeventfds, list)1497 ioeventfd_free(kioeventfd);1498 spin_unlock_irqrestore(&kioreq->lock, flags);1499 1500 ioreq_free(kioreq);1501 }1502 mutex_unlock(&ioreq_lock);1503}1504#else1505static inline long privcmd_ioctl_irqfd(struct file *file, void __user *udata)1506{1507 return -EOPNOTSUPP;1508}1509 1510static inline int privcmd_irqfd_init(void)1511{1512 return 0;1513}1514 1515static inline void privcmd_irqfd_exit(void)1516{1517}1518 1519static inline long privcmd_ioctl_ioeventfd(struct file *file, void __user *udata)1520{1521 return -EOPNOTSUPP;1522}1523 1524static inline void privcmd_ioeventfd_exit(void)1525{1526}1527#endif /* CONFIG_XEN_PRIVCMD_EVENTFD */1528 1529static long privcmd_ioctl(struct file *file,1530 unsigned int cmd, unsigned long data)1531{1532 int ret = -ENOTTY;1533 void __user *udata = (void __user *) data;1534 1535 switch (cmd) {1536 case IOCTL_PRIVCMD_HYPERCALL:1537 ret = privcmd_ioctl_hypercall(file, udata);1538 break;1539 1540 case IOCTL_PRIVCMD_MMAP:1541 ret = privcmd_ioctl_mmap(file, udata);1542 break;1543 1544 case IOCTL_PRIVCMD_MMAPBATCH:1545 ret = privcmd_ioctl_mmap_batch(file, udata, 1);1546 break;1547 1548 case IOCTL_PRIVCMD_MMAPBATCH_V2:1549 ret = privcmd_ioctl_mmap_batch(file, udata, 2);1550 break;1551 1552 case IOCTL_PRIVCMD_DM_OP:1553 ret = privcmd_ioctl_dm_op(file, udata);1554 break;1555 1556 case IOCTL_PRIVCMD_RESTRICT:1557 ret = privcmd_ioctl_restrict(file, udata);1558 break;1559 1560 case IOCTL_PRIVCMD_MMAP_RESOURCE:1561 ret = privcmd_ioctl_mmap_resource(file, udata);1562 break;1563 1564 case IOCTL_PRIVCMD_IRQFD:1565 ret = privcmd_ioctl_irqfd(file, udata);1566 break;1567 1568 case IOCTL_PRIVCMD_IOEVENTFD:1569 ret = privcmd_ioctl_ioeventfd(file, udata);1570 break;1571 1572 case IOCTL_PRIVCMD_PCIDEV_GET_GSI:1573 ret = privcmd_ioctl_pcidev_get_gsi(file, udata);1574 break;1575 1576 default:1577 break;1578 }1579 1580 return ret;1581}1582 1583static int privcmd_open(struct inode *ino, struct file *file)1584{1585 struct privcmd_data *data = kzalloc(sizeof(*data), GFP_KERNEL);1586 1587 if (!data)1588 return -ENOMEM;1589 1590 /* DOMID_INVALID implies no restriction */1591 data->domid = DOMID_INVALID;1592 1593 file->private_data = data;1594 return 0;1595}1596 1597static int privcmd_release(struct inode *ino, struct file *file)1598{1599 struct privcmd_data *data = file->private_data;1600 1601 kfree(data);1602 return 0;1603}1604 1605static void privcmd_close(struct vm_area_struct *vma)1606{1607 struct page **pages = vma->vm_private_data;1608 int numpgs = vma_pages(vma);1609 int numgfns = (vma->vm_end - vma->vm_start) >> XEN_PAGE_SHIFT;1610 int rc;1611 1612 if (!xen_feature(XENFEAT_auto_translated_physmap) || !numpgs || !pages)1613 return;1614 1615 rc = xen_unmap_domain_gfn_range(vma, numgfns, pages);1616 if (rc == 0)1617 xen_free_unpopulated_pages(numpgs, pages);1618 else1619 pr_crit("unable to unmap MFN range: leaking %d pages. rc=%d\n",1620 numpgs, rc);1621 kvfree(pages);1622}1623 1624static vm_fault_t privcmd_fault(struct vm_fault *vmf)1625{1626 printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n",1627 vmf->vma, vmf->vma->vm_start, vmf->vma->vm_end,1628 vmf->pgoff, (void *)vmf->address);1629 1630 return VM_FAULT_SIGBUS;1631}1632 1633static const struct vm_operations_struct privcmd_vm_ops = {1634 .close = privcmd_close,1635 .fault = privcmd_fault1636};1637 1638static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)1639{1640 /* DONTCOPY is essential for Xen because copy_page_range doesn't know1641 * how to recreate these mappings */1642 vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTCOPY |1643 VM_DONTEXPAND | VM_DONTDUMP);1644 vma->vm_ops = &privcmd_vm_ops;1645 vma->vm_private_data = NULL;1646 1647 return 0;1648}1649 1650/*1651 * For MMAPBATCH*. This allows asserting the singleshot mapping1652 * on a per pfn/pte basis. Mapping calls that fail with ENOENT1653 * can be then retried until success.1654 */1655static int is_mapped_fn(pte_t *pte, unsigned long addr, void *data)1656{1657 return pte_none(ptep_get(pte)) ? 0 : -EBUSY;1658}1659 1660static int privcmd_vma_range_is_mapped(1661 struct vm_area_struct *vma,1662 unsigned long addr,1663 unsigned long nr_pages)1664{1665 return apply_to_page_range(vma->vm_mm, addr, nr_pages << PAGE_SHIFT,1666 is_mapped_fn, NULL) != 0;1667}1668 1669const struct file_operations xen_privcmd_fops = {1670 .owner = THIS_MODULE,1671 .unlocked_ioctl = privcmd_ioctl,1672 .open = privcmd_open,1673 .release = privcmd_release,1674 .mmap = privcmd_mmap,1675};1676EXPORT_SYMBOL_GPL(xen_privcmd_fops);1677 1678static struct miscdevice privcmd_dev = {1679 .minor = MISC_DYNAMIC_MINOR,1680 .name = "xen/privcmd",1681 .fops = &xen_privcmd_fops,1682};1683 1684static int __init privcmd_init(void)1685{1686 int err;1687 1688 if (!xen_domain())1689 return -ENODEV;1690 1691 err = misc_register(&privcmd_dev);1692 if (err != 0) {1693 pr_err("Could not register Xen privcmd device\n");1694 return err;1695 }1696 1697 err = misc_register(&xen_privcmdbuf_dev);1698 if (err != 0) {1699 pr_err("Could not register Xen hypercall-buf device\n");1700 goto err_privcmdbuf;1701 }1702 1703 err = privcmd_irqfd_init();1704 if (err != 0) {1705 pr_err("irqfd init failed\n");1706 goto err_irqfd;1707 }1708 1709 return 0;1710 1711err_irqfd:1712 misc_deregister(&xen_privcmdbuf_dev);1713err_privcmdbuf:1714 misc_deregister(&privcmd_dev);1715 return err;1716}1717 1718static void __exit privcmd_exit(void)1719{1720 privcmd_ioeventfd_exit();1721 privcmd_irqfd_exit();1722 misc_deregister(&privcmd_dev);1723 misc_deregister(&xen_privcmdbuf_dev);1724}1725 1726module_init(privcmd_init);1727module_exit(privcmd_exit);1728