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1/*2 * Copyright (c) 2005 Topspin Communications. All rights reserved.3 * Copyright (c) 2005, 2006 Cisco Systems. All rights reserved.4 * Copyright (c) 2005 Mellanox Technologies. All rights reserved.5 * Copyright (c) 2005 Voltaire, Inc. All rights reserved.6 * Copyright (c) 2005 PathScale, Inc. All rights reserved.7 *8 * This software is available to you under a choice of one of two9 * licenses. You may choose to be licensed under the terms of the GNU10 * General Public License (GPL) Version 2, available from the file11 * COPYING in the main directory of this source tree, or the12 * OpenIB.org BSD license below:13 *14 * Redistribution and use in source and binary forms, with or15 * without modification, are permitted provided that the following16 * conditions are met:17 *18 * - Redistributions of source code must retain the above19 * copyright notice, this list of conditions and the following20 * disclaimer.21 *22 * - Redistributions in binary form must reproduce the above23 * copyright notice, this list of conditions and the following24 * disclaimer in the documentation and/or other materials25 * provided with the distribution.26 *27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,28 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF29 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND30 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS31 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN32 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN33 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE34 * SOFTWARE.35 */36 37#include <linux/module.h>38#include <linux/init.h>39#include <linux/device.h>40#include <linux/err.h>41#include <linux/fs.h>42#include <linux/poll.h>43#include <linux/sched.h>44#include <linux/file.h>45#include <linux/cdev.h>46#include <linux/anon_inodes.h>47#include <linux/slab.h>48#include <linux/sched/mm.h>49 50#include <linux/uaccess.h>51 52#include <rdma/ib.h>53#include <rdma/uverbs_std_types.h>54#include <rdma/rdma_netlink.h>55 56#include "uverbs.h"57#include "core_priv.h"58#include "rdma_core.h"59 60MODULE_AUTHOR("Roland Dreier");61MODULE_DESCRIPTION("InfiniBand userspace verbs access");62MODULE_LICENSE("Dual BSD/GPL");63 64enum {65 IB_UVERBS_MAJOR = 231,66 IB_UVERBS_BASE_MINOR = 192,67 IB_UVERBS_MAX_DEVICES = RDMA_MAX_PORTS,68 IB_UVERBS_NUM_FIXED_MINOR = 32,69 IB_UVERBS_NUM_DYNAMIC_MINOR = IB_UVERBS_MAX_DEVICES - IB_UVERBS_NUM_FIXED_MINOR,70};71 72#define IB_UVERBS_BASE_DEV MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)73 74static dev_t dynamic_uverbs_dev;75 76static DEFINE_IDA(uverbs_ida);77static int ib_uverbs_add_one(struct ib_device *device);78static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);79 80static char *uverbs_devnode(const struct device *dev, umode_t *mode)81{82 if (mode)83 *mode = 0666;84 return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));85}86 87static const struct class uverbs_class = {88 .name = "infiniband_verbs",89 .devnode = uverbs_devnode,90};91 92/*93 * Must be called with the ufile->device->disassociate_srcu held, and the lock94 * must be held until use of the ucontext is finished.95 */96struct ib_ucontext *ib_uverbs_get_ucontext_file(struct ib_uverbs_file *ufile)97{98 /*99 * We do not hold the hw_destroy_rwsem lock for this flow, instead100 * srcu is used. It does not matter if someone races this with101 * get_context, we get NULL or valid ucontext.102 */103 struct ib_ucontext *ucontext = smp_load_acquire(&ufile->ucontext);104 105 if (!srcu_dereference(ufile->device->ib_dev,106 &ufile->device->disassociate_srcu))107 return ERR_PTR(-EIO);108 109 if (!ucontext)110 return ERR_PTR(-EINVAL);111 112 return ucontext;113}114EXPORT_SYMBOL(ib_uverbs_get_ucontext_file);115 116int uverbs_dealloc_mw(struct ib_mw *mw)117{118 struct ib_pd *pd = mw->pd;119 int ret;120 121 ret = mw->device->ops.dealloc_mw(mw);122 if (ret)123 return ret;124 125 atomic_dec(&pd->usecnt);126 kfree(mw);127 return ret;128}129 130static void ib_uverbs_release_dev(struct device *device)131{132 struct ib_uverbs_device *dev =133 container_of(device, struct ib_uverbs_device, dev);134 135 uverbs_destroy_api(dev->uapi);136 cleanup_srcu_struct(&dev->disassociate_srcu);137 mutex_destroy(&dev->lists_mutex);138 mutex_destroy(&dev->xrcd_tree_mutex);139 kfree(dev);140}141 142void ib_uverbs_release_ucq(struct ib_uverbs_completion_event_file *ev_file,143 struct ib_ucq_object *uobj)144{145 struct ib_uverbs_event *evt, *tmp;146 147 if (ev_file) {148 spin_lock_irq(&ev_file->ev_queue.lock);149 list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {150 list_del(&evt->list);151 kfree(evt);152 }153 spin_unlock_irq(&ev_file->ev_queue.lock);154 155 uverbs_uobject_put(&ev_file->uobj);156 }157 158 ib_uverbs_release_uevent(&uobj->uevent);159}160 161void ib_uverbs_release_uevent(struct ib_uevent_object *uobj)162{163 struct ib_uverbs_async_event_file *async_file = uobj->event_file;164 struct ib_uverbs_event *evt, *tmp;165 166 if (!async_file)167 return;168 169 spin_lock_irq(&async_file->ev_queue.lock);170 list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {171 list_del(&evt->list);172 kfree(evt);173 }174 spin_unlock_irq(&async_file->ev_queue.lock);175 uverbs_uobject_put(&async_file->uobj);176}177 178void ib_uverbs_detach_umcast(struct ib_qp *qp,179 struct ib_uqp_object *uobj)180{181 struct ib_uverbs_mcast_entry *mcast, *tmp;182 183 list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {184 ib_detach_mcast(qp, &mcast->gid, mcast->lid);185 list_del(&mcast->list);186 kfree(mcast);187 }188}189 190static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)191{192 complete(&dev->comp);193}194 195void ib_uverbs_release_file(struct kref *ref)196{197 struct ib_uverbs_file *file =198 container_of(ref, struct ib_uverbs_file, ref);199 struct ib_device *ib_dev;200 int srcu_key;201 202 release_ufile_idr_uobject(file);203 204 srcu_key = srcu_read_lock(&file->device->disassociate_srcu);205 ib_dev = srcu_dereference(file->device->ib_dev,206 &file->device->disassociate_srcu);207 if (ib_dev && !ib_dev->ops.disassociate_ucontext)208 module_put(ib_dev->ops.owner);209 srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);210 211 if (refcount_dec_and_test(&file->device->refcount))212 ib_uverbs_comp_dev(file->device);213 214 if (file->default_async_file)215 uverbs_uobject_put(&file->default_async_file->uobj);216 put_device(&file->device->dev);217 218 if (file->disassociate_page)219 __free_pages(file->disassociate_page, 0);220 mutex_destroy(&file->umap_lock);221 mutex_destroy(&file->ucontext_lock);222 kfree(file);223}224 225static ssize_t ib_uverbs_event_read(struct ib_uverbs_event_queue *ev_queue,226 struct file *filp, char __user *buf,227 size_t count, loff_t *pos,228 size_t eventsz)229{230 struct ib_uverbs_event *event;231 int ret = 0;232 233 spin_lock_irq(&ev_queue->lock);234 235 while (list_empty(&ev_queue->event_list)) {236 if (ev_queue->is_closed) {237 spin_unlock_irq(&ev_queue->lock);238 return -EIO;239 }240 241 spin_unlock_irq(&ev_queue->lock);242 if (filp->f_flags & O_NONBLOCK)243 return -EAGAIN;244 245 if (wait_event_interruptible(ev_queue->poll_wait,246 (!list_empty(&ev_queue->event_list) ||247 ev_queue->is_closed)))248 return -ERESTARTSYS;249 250 spin_lock_irq(&ev_queue->lock);251 }252 253 event = list_entry(ev_queue->event_list.next, struct ib_uverbs_event, list);254 255 if (eventsz > count) {256 ret = -EINVAL;257 event = NULL;258 } else {259 list_del(ev_queue->event_list.next);260 if (event->counter) {261 ++(*event->counter);262 list_del(&event->obj_list);263 }264 }265 266 spin_unlock_irq(&ev_queue->lock);267 268 if (event) {269 if (copy_to_user(buf, event, eventsz))270 ret = -EFAULT;271 else272 ret = eventsz;273 }274 275 kfree(event);276 277 return ret;278}279 280static ssize_t ib_uverbs_async_event_read(struct file *filp, char __user *buf,281 size_t count, loff_t *pos)282{283 struct ib_uverbs_async_event_file *file = filp->private_data;284 285 return ib_uverbs_event_read(&file->ev_queue, filp, buf, count, pos,286 sizeof(struct ib_uverbs_async_event_desc));287}288 289static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf,290 size_t count, loff_t *pos)291{292 struct ib_uverbs_completion_event_file *comp_ev_file =293 filp->private_data;294 295 return ib_uverbs_event_read(&comp_ev_file->ev_queue, filp, buf, count,296 pos,297 sizeof(struct ib_uverbs_comp_event_desc));298}299 300static __poll_t ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,301 struct file *filp,302 struct poll_table_struct *wait)303{304 __poll_t pollflags = 0;305 306 poll_wait(filp, &ev_queue->poll_wait, wait);307 308 spin_lock_irq(&ev_queue->lock);309 if (!list_empty(&ev_queue->event_list))310 pollflags = EPOLLIN | EPOLLRDNORM;311 else if (ev_queue->is_closed)312 pollflags = EPOLLERR;313 spin_unlock_irq(&ev_queue->lock);314 315 return pollflags;316}317 318static __poll_t ib_uverbs_async_event_poll(struct file *filp,319 struct poll_table_struct *wait)320{321 struct ib_uverbs_async_event_file *file = filp->private_data;322 323 return ib_uverbs_event_poll(&file->ev_queue, filp, wait);324}325 326static __poll_t ib_uverbs_comp_event_poll(struct file *filp,327 struct poll_table_struct *wait)328{329 struct ib_uverbs_completion_event_file *comp_ev_file =330 filp->private_data;331 332 return ib_uverbs_event_poll(&comp_ev_file->ev_queue, filp, wait);333}334 335static int ib_uverbs_async_event_fasync(int fd, struct file *filp, int on)336{337 struct ib_uverbs_async_event_file *file = filp->private_data;338 339 return fasync_helper(fd, filp, on, &file->ev_queue.async_queue);340}341 342static int ib_uverbs_comp_event_fasync(int fd, struct file *filp, int on)343{344 struct ib_uverbs_completion_event_file *comp_ev_file =345 filp->private_data;346 347 return fasync_helper(fd, filp, on, &comp_ev_file->ev_queue.async_queue);348}349 350const struct file_operations uverbs_event_fops = {351 .owner = THIS_MODULE,352 .read = ib_uverbs_comp_event_read,353 .poll = ib_uverbs_comp_event_poll,354 .release = uverbs_uobject_fd_release,355 .fasync = ib_uverbs_comp_event_fasync,356};357 358const struct file_operations uverbs_async_event_fops = {359 .owner = THIS_MODULE,360 .read = ib_uverbs_async_event_read,361 .poll = ib_uverbs_async_event_poll,362 .release = uverbs_async_event_release,363 .fasync = ib_uverbs_async_event_fasync,364};365 366void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)367{368 struct ib_uverbs_event_queue *ev_queue = cq_context;369 struct ib_ucq_object *uobj;370 struct ib_uverbs_event *entry;371 unsigned long flags;372 373 if (!ev_queue)374 return;375 376 spin_lock_irqsave(&ev_queue->lock, flags);377 if (ev_queue->is_closed) {378 spin_unlock_irqrestore(&ev_queue->lock, flags);379 return;380 }381 382 entry = kmalloc(sizeof(*entry), GFP_ATOMIC);383 if (!entry) {384 spin_unlock_irqrestore(&ev_queue->lock, flags);385 return;386 }387 388 uobj = cq->uobject;389 390 entry->desc.comp.cq_handle = cq->uobject->uevent.uobject.user_handle;391 entry->counter = &uobj->comp_events_reported;392 393 list_add_tail(&entry->list, &ev_queue->event_list);394 list_add_tail(&entry->obj_list, &uobj->comp_list);395 spin_unlock_irqrestore(&ev_queue->lock, flags);396 397 wake_up_interruptible(&ev_queue->poll_wait);398 kill_fasync(&ev_queue->async_queue, SIGIO, POLL_IN);399}400 401void ib_uverbs_async_handler(struct ib_uverbs_async_event_file *async_file,402 __u64 element, __u64 event,403 struct list_head *obj_list, u32 *counter)404{405 struct ib_uverbs_event *entry;406 unsigned long flags;407 408 if (!async_file)409 return;410 411 spin_lock_irqsave(&async_file->ev_queue.lock, flags);412 if (async_file->ev_queue.is_closed) {413 spin_unlock_irqrestore(&async_file->ev_queue.lock, flags);414 return;415 }416 417 entry = kmalloc(sizeof(*entry), GFP_ATOMIC);418 if (!entry) {419 spin_unlock_irqrestore(&async_file->ev_queue.lock, flags);420 return;421 }422 423 entry->desc.async.element = element;424 entry->desc.async.event_type = event;425 entry->desc.async.reserved = 0;426 entry->counter = counter;427 428 list_add_tail(&entry->list, &async_file->ev_queue.event_list);429 if (obj_list)430 list_add_tail(&entry->obj_list, obj_list);431 spin_unlock_irqrestore(&async_file->ev_queue.lock, flags);432 433 wake_up_interruptible(&async_file->ev_queue.poll_wait);434 kill_fasync(&async_file->ev_queue.async_queue, SIGIO, POLL_IN);435}436 437static void uverbs_uobj_event(struct ib_uevent_object *eobj,438 struct ib_event *event)439{440 ib_uverbs_async_handler(eobj->event_file,441 eobj->uobject.user_handle, event->event,442 &eobj->event_list, &eobj->events_reported);443}444 445void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)446{447 uverbs_uobj_event(&event->element.cq->uobject->uevent, event);448}449 450void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)451{452 /* for XRC target qp's, check that qp is live */453 if (!event->element.qp->uobject)454 return;455 456 uverbs_uobj_event(&event->element.qp->uobject->uevent, event);457}458 459void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)460{461 uverbs_uobj_event(&event->element.wq->uobject->uevent, event);462}463 464void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)465{466 uverbs_uobj_event(&event->element.srq->uobject->uevent, event);467}468 469static void ib_uverbs_event_handler(struct ib_event_handler *handler,470 struct ib_event *event)471{472 ib_uverbs_async_handler(473 container_of(handler, struct ib_uverbs_async_event_file,474 event_handler),475 event->element.port_num, event->event, NULL, NULL);476}477 478void ib_uverbs_init_event_queue(struct ib_uverbs_event_queue *ev_queue)479{480 spin_lock_init(&ev_queue->lock);481 INIT_LIST_HEAD(&ev_queue->event_list);482 init_waitqueue_head(&ev_queue->poll_wait);483 ev_queue->is_closed = 0;484 ev_queue->async_queue = NULL;485}486 487void ib_uverbs_init_async_event_file(488 struct ib_uverbs_async_event_file *async_file)489{490 struct ib_uverbs_file *uverbs_file = async_file->uobj.ufile;491 struct ib_device *ib_dev = async_file->uobj.context->device;492 493 ib_uverbs_init_event_queue(&async_file->ev_queue);494 495 /* The first async_event_file becomes the default one for the file. */496 mutex_lock(&uverbs_file->ucontext_lock);497 if (!uverbs_file->default_async_file) {498 /* Pairs with the put in ib_uverbs_release_file */499 uverbs_uobject_get(&async_file->uobj);500 smp_store_release(&uverbs_file->default_async_file, async_file);501 }502 mutex_unlock(&uverbs_file->ucontext_lock);503 504 INIT_IB_EVENT_HANDLER(&async_file->event_handler, ib_dev,505 ib_uverbs_event_handler);506 ib_register_event_handler(&async_file->event_handler);507}508 509static ssize_t verify_hdr(struct ib_uverbs_cmd_hdr *hdr,510 struct ib_uverbs_ex_cmd_hdr *ex_hdr, size_t count,511 const struct uverbs_api_write_method *method_elm)512{513 if (method_elm->is_ex) {514 count -= sizeof(*hdr) + sizeof(*ex_hdr);515 516 if ((hdr->in_words + ex_hdr->provider_in_words) * 8 != count)517 return -EINVAL;518 519 if (hdr->in_words * 8 < method_elm->req_size)520 return -ENOSPC;521 522 if (ex_hdr->cmd_hdr_reserved)523 return -EINVAL;524 525 if (ex_hdr->response) {526 if (!hdr->out_words && !ex_hdr->provider_out_words)527 return -EINVAL;528 529 if (hdr->out_words * 8 < method_elm->resp_size)530 return -ENOSPC;531 532 if (!access_ok(u64_to_user_ptr(ex_hdr->response),533 (hdr->out_words + ex_hdr->provider_out_words) * 8))534 return -EFAULT;535 } else {536 if (hdr->out_words || ex_hdr->provider_out_words)537 return -EINVAL;538 }539 540 return 0;541 }542 543 /* not extended command */544 if (hdr->in_words * 4 != count)545 return -EINVAL;546 547 if (count < method_elm->req_size + sizeof(*hdr)) {548 /*549 * rdma-core v18 and v19 have a bug where they send DESTROY_CQ550 * with a 16 byte write instead of 24. Old kernels didn't551 * check the size so they allowed this. Now that the size is552 * checked provide a compatibility work around to not break553 * those userspaces.554 */555 if (hdr->command == IB_USER_VERBS_CMD_DESTROY_CQ &&556 count == 16) {557 hdr->in_words = 6;558 return 0;559 }560 return -ENOSPC;561 }562 if (hdr->out_words * 4 < method_elm->resp_size)563 return -ENOSPC;564 565 return 0;566}567 568static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,569 size_t count, loff_t *pos)570{571 struct ib_uverbs_file *file = filp->private_data;572 const struct uverbs_api_write_method *method_elm;573 struct uverbs_api *uapi = file->device->uapi;574 struct ib_uverbs_ex_cmd_hdr ex_hdr;575 struct ib_uverbs_cmd_hdr hdr;576 struct uverbs_attr_bundle bundle;577 int srcu_key;578 ssize_t ret;579 580 if (!ib_safe_file_access(filp)) {581 pr_err_once("uverbs_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",582 task_tgid_vnr(current), current->comm);583 return -EACCES;584 }585 586 if (count < sizeof(hdr))587 return -EINVAL;588 589 if (copy_from_user(&hdr, buf, sizeof(hdr)))590 return -EFAULT;591 592 method_elm = uapi_get_method(uapi, hdr.command);593 if (IS_ERR(method_elm))594 return PTR_ERR(method_elm);595 596 if (method_elm->is_ex) {597 if (count < (sizeof(hdr) + sizeof(ex_hdr)))598 return -EINVAL;599 if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr)))600 return -EFAULT;601 }602 603 ret = verify_hdr(&hdr, &ex_hdr, count, method_elm);604 if (ret)605 return ret;606 607 srcu_key = srcu_read_lock(&file->device->disassociate_srcu);608 609 buf += sizeof(hdr);610 611 memset(bundle.attr_present, 0, sizeof(bundle.attr_present));612 bundle.ufile = file;613 bundle.context = NULL; /* only valid if bundle has uobject */614 bundle.uobject = NULL;615 if (!method_elm->is_ex) {616 size_t in_len = hdr.in_words * 4 - sizeof(hdr);617 size_t out_len = hdr.out_words * 4;618 u64 response = 0;619 620 if (method_elm->has_udata) {621 bundle.driver_udata.inlen =622 in_len - method_elm->req_size;623 in_len = method_elm->req_size;624 if (bundle.driver_udata.inlen)625 bundle.driver_udata.inbuf = buf + in_len;626 else627 bundle.driver_udata.inbuf = NULL;628 } else {629 memset(&bundle.driver_udata, 0,630 sizeof(bundle.driver_udata));631 }632 633 if (method_elm->has_resp) {634 /*635 * The macros check that if has_resp is set636 * then the command request structure starts637 * with a '__aligned u64 response' member.638 */639 ret = get_user(response, (const u64 __user *)buf);640 if (ret)641 goto out_unlock;642 643 if (method_elm->has_udata) {644 bundle.driver_udata.outlen =645 out_len - method_elm->resp_size;646 out_len = method_elm->resp_size;647 if (bundle.driver_udata.outlen)648 bundle.driver_udata.outbuf =649 u64_to_user_ptr(response +650 out_len);651 else652 bundle.driver_udata.outbuf = NULL;653 }654 } else {655 bundle.driver_udata.outlen = 0;656 bundle.driver_udata.outbuf = NULL;657 }658 659 ib_uverbs_init_udata_buf_or_null(660 &bundle.ucore, buf, u64_to_user_ptr(response),661 in_len, out_len);662 } else {663 buf += sizeof(ex_hdr);664 665 ib_uverbs_init_udata_buf_or_null(&bundle.ucore, buf,666 u64_to_user_ptr(ex_hdr.response),667 hdr.in_words * 8, hdr.out_words * 8);668 669 ib_uverbs_init_udata_buf_or_null(670 &bundle.driver_udata, buf + bundle.ucore.inlen,671 u64_to_user_ptr(ex_hdr.response) + bundle.ucore.outlen,672 ex_hdr.provider_in_words * 8,673 ex_hdr.provider_out_words * 8);674 675 }676 677 ret = method_elm->handler(&bundle);678 if (bundle.uobject)679 uverbs_finalize_object(bundle.uobject, UVERBS_ACCESS_NEW, true,680 !ret, &bundle);681out_unlock:682 srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);683 return (ret) ? : count;684}685 686static const struct vm_operations_struct rdma_umap_ops;687 688static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)689{690 struct ib_uverbs_file *file = filp->private_data;691 struct ib_ucontext *ucontext;692 int ret = 0;693 int srcu_key;694 695 srcu_key = srcu_read_lock(&file->device->disassociate_srcu);696 ucontext = ib_uverbs_get_ucontext_file(file);697 if (IS_ERR(ucontext)) {698 ret = PTR_ERR(ucontext);699 goto out;700 }701 vma->vm_ops = &rdma_umap_ops;702 ret = ucontext->device->ops.mmap(ucontext, vma);703out:704 srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);705 return ret;706}707 708/*709 * The VMA has been dup'd, initialize the vm_private_data with a new tracking710 * struct711 */712static void rdma_umap_open(struct vm_area_struct *vma)713{714 struct ib_uverbs_file *ufile = vma->vm_file->private_data;715 struct rdma_umap_priv *opriv = vma->vm_private_data;716 struct rdma_umap_priv *priv;717 718 if (!opriv)719 return;720 721 /* We are racing with disassociation */722 if (!down_read_trylock(&ufile->hw_destroy_rwsem))723 goto out_zap;724 /*725 * Disassociation already completed, the VMA should already be zapped.726 */727 if (!ufile->ucontext)728 goto out_unlock;729 730 priv = kzalloc(sizeof(*priv), GFP_KERNEL);731 if (!priv)732 goto out_unlock;733 rdma_umap_priv_init(priv, vma, opriv->entry);734 735 up_read(&ufile->hw_destroy_rwsem);736 return;737 738out_unlock:739 up_read(&ufile->hw_destroy_rwsem);740out_zap:741 /*742 * We can't allow the VMA to be created with the actual IO pages, that743 * would break our API contract, and it can't be stopped at this744 * point, so zap it.745 */746 vma->vm_private_data = NULL;747 zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start);748}749 750static void rdma_umap_close(struct vm_area_struct *vma)751{752 struct ib_uverbs_file *ufile = vma->vm_file->private_data;753 struct rdma_umap_priv *priv = vma->vm_private_data;754 755 if (!priv)756 return;757 758 /*759 * The vma holds a reference on the struct file that created it, which760 * in turn means that the ib_uverbs_file is guaranteed to exist at761 * this point.762 */763 mutex_lock(&ufile->umap_lock);764 if (priv->entry)765 rdma_user_mmap_entry_put(priv->entry);766 767 list_del(&priv->list);768 mutex_unlock(&ufile->umap_lock);769 kfree(priv);770}771 772/*773 * Once the zap_vma_ptes has been called touches to the VMA will come here and774 * we return a dummy writable zero page for all the pfns.775 */776static vm_fault_t rdma_umap_fault(struct vm_fault *vmf)777{778 struct ib_uverbs_file *ufile = vmf->vma->vm_file->private_data;779 struct rdma_umap_priv *priv = vmf->vma->vm_private_data;780 vm_fault_t ret = 0;781 782 if (!priv)783 return VM_FAULT_SIGBUS;784 785 /* Read only pages can just use the system zero page. */786 if (!(vmf->vma->vm_flags & (VM_WRITE | VM_MAYWRITE))) {787 vmf->page = ZERO_PAGE(vmf->address);788 get_page(vmf->page);789 return 0;790 }791 792 mutex_lock(&ufile->umap_lock);793 if (!ufile->disassociate_page)794 ufile->disassociate_page =795 alloc_pages(vmf->gfp_mask | __GFP_ZERO, 0);796 797 if (ufile->disassociate_page) {798 /*799 * This VMA is forced to always be shared so this doesn't have800 * to worry about COW.801 */802 vmf->page = ufile->disassociate_page;803 get_page(vmf->page);804 } else {805 ret = VM_FAULT_SIGBUS;806 }807 mutex_unlock(&ufile->umap_lock);808 809 return ret;810}811 812static const struct vm_operations_struct rdma_umap_ops = {813 .open = rdma_umap_open,814 .close = rdma_umap_close,815 .fault = rdma_umap_fault,816};817 818void uverbs_user_mmap_disassociate(struct ib_uverbs_file *ufile)819{820 struct rdma_umap_priv *priv, *next_priv;821 822 lockdep_assert_held(&ufile->hw_destroy_rwsem);823 824 while (1) {825 struct mm_struct *mm = NULL;826 827 /* Get an arbitrary mm pointer that hasn't been cleaned yet */828 mutex_lock(&ufile->umap_lock);829 while (!list_empty(&ufile->umaps)) {830 int ret;831 832 priv = list_first_entry(&ufile->umaps,833 struct rdma_umap_priv, list);834 mm = priv->vma->vm_mm;835 ret = mmget_not_zero(mm);836 if (!ret) {837 list_del_init(&priv->list);838 if (priv->entry) {839 rdma_user_mmap_entry_put(priv->entry);840 priv->entry = NULL;841 }842 mm = NULL;843 continue;844 }845 break;846 }847 mutex_unlock(&ufile->umap_lock);848 if (!mm)849 return;850 851 /*852 * The umap_lock is nested under mmap_lock since it used within853 * the vma_ops callbacks, so we have to clean the list one mm854 * at a time to get the lock ordering right. Typically there855 * will only be one mm, so no big deal.856 */857 mmap_read_lock(mm);858 mutex_lock(&ufile->umap_lock);859 list_for_each_entry_safe (priv, next_priv, &ufile->umaps,860 list) {861 struct vm_area_struct *vma = priv->vma;862 863 if (vma->vm_mm != mm)864 continue;865 list_del_init(&priv->list);866 867 zap_vma_ptes(vma, vma->vm_start,868 vma->vm_end - vma->vm_start);869 870 if (priv->entry) {871 rdma_user_mmap_entry_put(priv->entry);872 priv->entry = NULL;873 }874 }875 mutex_unlock(&ufile->umap_lock);876 mmap_read_unlock(mm);877 mmput(mm);878 }879}880 881/*882 * ib_uverbs_open() does not need the BKL:883 *884 * - the ib_uverbs_device structures are properly reference counted and885 * everything else is purely local to the file being created, so886 * races against other open calls are not a problem;887 * - there is no ioctl method to race against;888 * - the open method will either immediately run -ENXIO, or all889 * required initialization will be done.890 */891static int ib_uverbs_open(struct inode *inode, struct file *filp)892{893 struct ib_uverbs_device *dev;894 struct ib_uverbs_file *file;895 struct ib_device *ib_dev;896 int ret;897 int module_dependent;898 int srcu_key;899 900 dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);901 if (!refcount_inc_not_zero(&dev->refcount))902 return -ENXIO;903 904 get_device(&dev->dev);905 srcu_key = srcu_read_lock(&dev->disassociate_srcu);906 mutex_lock(&dev->lists_mutex);907 ib_dev = srcu_dereference(dev->ib_dev,908 &dev->disassociate_srcu);909 if (!ib_dev) {910 ret = -EIO;911 goto err;912 }913 914 if (!rdma_dev_access_netns(ib_dev, current->nsproxy->net_ns)) {915 ret = -EPERM;916 goto err;917 }918 919 /* In case IB device supports disassociate ucontext, there is no hard920 * dependency between uverbs device and its low level device.921 */922 module_dependent = !(ib_dev->ops.disassociate_ucontext);923 924 if (module_dependent) {925 if (!try_module_get(ib_dev->ops.owner)) {926 ret = -ENODEV;927 goto err;928 }929 }930 931 file = kzalloc(sizeof(*file), GFP_KERNEL);932 if (!file) {933 ret = -ENOMEM;934 if (module_dependent)935 goto err_module;936 937 goto err;938 }939 940 file->device = dev;941 kref_init(&file->ref);942 mutex_init(&file->ucontext_lock);943 944 spin_lock_init(&file->uobjects_lock);945 INIT_LIST_HEAD(&file->uobjects);946 init_rwsem(&file->hw_destroy_rwsem);947 mutex_init(&file->umap_lock);948 INIT_LIST_HEAD(&file->umaps);949 950 filp->private_data = file;951 list_add_tail(&file->list, &dev->uverbs_file_list);952 mutex_unlock(&dev->lists_mutex);953 srcu_read_unlock(&dev->disassociate_srcu, srcu_key);954 955 setup_ufile_idr_uobject(file);956 957 return stream_open(inode, filp);958 959err_module:960 module_put(ib_dev->ops.owner);961 962err:963 mutex_unlock(&dev->lists_mutex);964 srcu_read_unlock(&dev->disassociate_srcu, srcu_key);965 if (refcount_dec_and_test(&dev->refcount))966 ib_uverbs_comp_dev(dev);967 968 put_device(&dev->dev);969 return ret;970}971 972static int ib_uverbs_close(struct inode *inode, struct file *filp)973{974 struct ib_uverbs_file *file = filp->private_data;975 976 uverbs_destroy_ufile_hw(file, RDMA_REMOVE_CLOSE);977 978 mutex_lock(&file->device->lists_mutex);979 list_del_init(&file->list);980 mutex_unlock(&file->device->lists_mutex);981 982 kref_put(&file->ref, ib_uverbs_release_file);983 984 return 0;985}986 987static const struct file_operations uverbs_fops = {988 .owner = THIS_MODULE,989 .write = ib_uverbs_write,990 .open = ib_uverbs_open,991 .release = ib_uverbs_close,992 .unlocked_ioctl = ib_uverbs_ioctl,993 .compat_ioctl = compat_ptr_ioctl,994};995 996static const struct file_operations uverbs_mmap_fops = {997 .owner = THIS_MODULE,998 .write = ib_uverbs_write,999 .mmap = ib_uverbs_mmap,1000 .open = ib_uverbs_open,1001 .release = ib_uverbs_close,1002 .unlocked_ioctl = ib_uverbs_ioctl,1003 .compat_ioctl = compat_ptr_ioctl,1004};1005 1006static int ib_uverbs_get_nl_info(struct ib_device *ibdev, void *client_data,1007 struct ib_client_nl_info *res)1008{1009 struct ib_uverbs_device *uverbs_dev = client_data;1010 int ret;1011 1012 if (res->port != -1)1013 return -EINVAL;1014 1015 res->abi = ibdev->ops.uverbs_abi_ver;1016 res->cdev = &uverbs_dev->dev;1017 1018 /*1019 * To support DRIVER_ID binding in userspace some of the driver need1020 * upgrading to expose their PCI dependent revision information1021 * through get_context instead of relying on modalias matching. When1022 * the drivers are fixed they can drop this flag.1023 */1024 if (!ibdev->ops.uverbs_no_driver_id_binding) {1025 ret = nla_put_u32(res->nl_msg, RDMA_NLDEV_ATTR_UVERBS_DRIVER_ID,1026 ibdev->ops.driver_id);1027 if (ret)1028 return ret;1029 }1030 return 0;1031}1032 1033static struct ib_client uverbs_client = {1034 .name = "uverbs",1035 .no_kverbs_req = true,1036 .add = ib_uverbs_add_one,1037 .remove = ib_uverbs_remove_one,1038 .get_nl_info = ib_uverbs_get_nl_info,1039};1040MODULE_ALIAS_RDMA_CLIENT("uverbs");1041 1042static ssize_t ibdev_show(struct device *device, struct device_attribute *attr,1043 char *buf)1044{1045 struct ib_uverbs_device *dev =1046 container_of(device, struct ib_uverbs_device, dev);1047 int ret = -ENODEV;1048 int srcu_key;1049 struct ib_device *ib_dev;1050 1051 srcu_key = srcu_read_lock(&dev->disassociate_srcu);1052 ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);1053 if (ib_dev)1054 ret = sysfs_emit(buf, "%s\n", dev_name(&ib_dev->dev));1055 srcu_read_unlock(&dev->disassociate_srcu, srcu_key);1056 1057 return ret;1058}1059static DEVICE_ATTR_RO(ibdev);1060 1061static ssize_t abi_version_show(struct device *device,1062 struct device_attribute *attr, char *buf)1063{1064 struct ib_uverbs_device *dev =1065 container_of(device, struct ib_uverbs_device, dev);1066 int ret = -ENODEV;1067 int srcu_key;1068 struct ib_device *ib_dev;1069 1070 srcu_key = srcu_read_lock(&dev->disassociate_srcu);1071 ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);1072 if (ib_dev)1073 ret = sysfs_emit(buf, "%u\n", ib_dev->ops.uverbs_abi_ver);1074 srcu_read_unlock(&dev->disassociate_srcu, srcu_key);1075 1076 return ret;1077}1078static DEVICE_ATTR_RO(abi_version);1079 1080static struct attribute *ib_dev_attrs[] = {1081 &dev_attr_abi_version.attr,1082 &dev_attr_ibdev.attr,1083 NULL,1084};1085 1086static const struct attribute_group dev_attr_group = {1087 .attrs = ib_dev_attrs,1088};1089 1090static CLASS_ATTR_STRING(abi_version, S_IRUGO,1091 __stringify(IB_USER_VERBS_ABI_VERSION));1092 1093static int ib_uverbs_create_uapi(struct ib_device *device,1094 struct ib_uverbs_device *uverbs_dev)1095{1096 struct uverbs_api *uapi;1097 1098 uapi = uverbs_alloc_api(device);1099 if (IS_ERR(uapi))1100 return PTR_ERR(uapi);1101 1102 uverbs_dev->uapi = uapi;1103 return 0;1104}1105 1106static int ib_uverbs_add_one(struct ib_device *device)1107{1108 int devnum;1109 dev_t base;1110 struct ib_uverbs_device *uverbs_dev;1111 int ret;1112 1113 if (!device->ops.alloc_ucontext ||1114 device->type == RDMA_DEVICE_TYPE_SMI)1115 return -EOPNOTSUPP;1116 1117 uverbs_dev = kzalloc(sizeof(*uverbs_dev), GFP_KERNEL);1118 if (!uverbs_dev)1119 return -ENOMEM;1120 1121 ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);1122 if (ret) {1123 kfree(uverbs_dev);1124 return -ENOMEM;1125 }1126 1127 device_initialize(&uverbs_dev->dev);1128 uverbs_dev->dev.class = &uverbs_class;1129 uverbs_dev->dev.parent = device->dev.parent;1130 uverbs_dev->dev.release = ib_uverbs_release_dev;1131 uverbs_dev->groups[0] = &dev_attr_group;1132 uverbs_dev->dev.groups = uverbs_dev->groups;1133 refcount_set(&uverbs_dev->refcount, 1);1134 init_completion(&uverbs_dev->comp);1135 uverbs_dev->xrcd_tree = RB_ROOT;1136 mutex_init(&uverbs_dev->xrcd_tree_mutex);1137 mutex_init(&uverbs_dev->lists_mutex);1138 INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);1139 rcu_assign_pointer(uverbs_dev->ib_dev, device);1140 uverbs_dev->num_comp_vectors = device->num_comp_vectors;1141 1142 devnum = ida_alloc_max(&uverbs_ida, IB_UVERBS_MAX_DEVICES - 1,1143 GFP_KERNEL);1144 if (devnum < 0) {1145 ret = -ENOMEM;1146 goto err;1147 }1148 uverbs_dev->devnum = devnum;1149 if (devnum >= IB_UVERBS_NUM_FIXED_MINOR)1150 base = dynamic_uverbs_dev + devnum - IB_UVERBS_NUM_FIXED_MINOR;1151 else1152 base = IB_UVERBS_BASE_DEV + devnum;1153 1154 ret = ib_uverbs_create_uapi(device, uverbs_dev);1155 if (ret)1156 goto err_uapi;1157 1158 uverbs_dev->dev.devt = base;1159 dev_set_name(&uverbs_dev->dev, "uverbs%d", uverbs_dev->devnum);1160 1161 cdev_init(&uverbs_dev->cdev,1162 device->ops.mmap ? &uverbs_mmap_fops : &uverbs_fops);1163 uverbs_dev->cdev.owner = THIS_MODULE;1164 1165 ret = cdev_device_add(&uverbs_dev->cdev, &uverbs_dev->dev);1166 if (ret)1167 goto err_uapi;1168 1169 ib_set_client_data(device, &uverbs_client, uverbs_dev);1170 return 0;1171 1172err_uapi:1173 ida_free(&uverbs_ida, devnum);1174err:1175 if (refcount_dec_and_test(&uverbs_dev->refcount))1176 ib_uverbs_comp_dev(uverbs_dev);1177 wait_for_completion(&uverbs_dev->comp);1178 put_device(&uverbs_dev->dev);1179 return ret;1180}1181 1182static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,1183 struct ib_device *ib_dev)1184{1185 struct ib_uverbs_file *file;1186 1187 /* Pending running commands to terminate */1188 uverbs_disassociate_api_pre(uverbs_dev);1189 1190 mutex_lock(&uverbs_dev->lists_mutex);1191 while (!list_empty(&uverbs_dev->uverbs_file_list)) {1192 file = list_first_entry(&uverbs_dev->uverbs_file_list,1193 struct ib_uverbs_file, list);1194 list_del_init(&file->list);1195 kref_get(&file->ref);1196 1197 /* We must release the mutex before going ahead and calling1198 * uverbs_cleanup_ufile, as it might end up indirectly calling1199 * uverbs_close, for example due to freeing the resources (e.g1200 * mmput).1201 */1202 mutex_unlock(&uverbs_dev->lists_mutex);1203 1204 uverbs_destroy_ufile_hw(file, RDMA_REMOVE_DRIVER_REMOVE);1205 kref_put(&file->ref, ib_uverbs_release_file);1206 1207 mutex_lock(&uverbs_dev->lists_mutex);1208 }1209 mutex_unlock(&uverbs_dev->lists_mutex);1210 1211 uverbs_disassociate_api(uverbs_dev->uapi);1212}1213 1214static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)1215{1216 struct ib_uverbs_device *uverbs_dev = client_data;1217 int wait_clients = 1;1218 1219 cdev_device_del(&uverbs_dev->cdev, &uverbs_dev->dev);1220 ida_free(&uverbs_ida, uverbs_dev->devnum);1221 1222 if (device->ops.disassociate_ucontext) {1223 /* We disassociate HW resources and immediately return.1224 * Userspace will see a EIO errno for all future access.1225 * Upon returning, ib_device may be freed internally and is not1226 * valid any more.1227 * uverbs_device is still available until all clients close1228 * their files, then the uverbs device ref count will be zero1229 * and its resources will be freed.1230 * Note: At this point no more files can be opened since the1231 * cdev was deleted, however active clients can still issue1232 * commands and close their open files.1233 */1234 ib_uverbs_free_hw_resources(uverbs_dev, device);1235 wait_clients = 0;1236 }1237 1238 if (refcount_dec_and_test(&uverbs_dev->refcount))1239 ib_uverbs_comp_dev(uverbs_dev);1240 if (wait_clients)1241 wait_for_completion(&uverbs_dev->comp);1242 1243 put_device(&uverbs_dev->dev);1244}1245 1246static int __init ib_uverbs_init(void)1247{1248 int ret;1249 1250 ret = register_chrdev_region(IB_UVERBS_BASE_DEV,1251 IB_UVERBS_NUM_FIXED_MINOR,1252 "infiniband_verbs");1253 if (ret) {1254 pr_err("user_verbs: couldn't register device number\n");1255 goto out;1256 }1257 1258 ret = alloc_chrdev_region(&dynamic_uverbs_dev, 0,1259 IB_UVERBS_NUM_DYNAMIC_MINOR,1260 "infiniband_verbs");1261 if (ret) {1262 pr_err("couldn't register dynamic device number\n");1263 goto out_alloc;1264 }1265 1266 ret = class_register(&uverbs_class);1267 if (ret) {1268 pr_err("user_verbs: couldn't create class infiniband_verbs\n");1269 goto out_chrdev;1270 }1271 1272 ret = class_create_file(&uverbs_class, &class_attr_abi_version.attr);1273 if (ret) {1274 pr_err("user_verbs: couldn't create abi_version attribute\n");1275 goto out_class;1276 }1277 1278 ret = ib_register_client(&uverbs_client);1279 if (ret) {1280 pr_err("user_verbs: couldn't register client\n");1281 goto out_class;1282 }1283 1284 return 0;1285 1286out_class:1287 class_unregister(&uverbs_class);1288 1289out_chrdev:1290 unregister_chrdev_region(dynamic_uverbs_dev,1291 IB_UVERBS_NUM_DYNAMIC_MINOR);1292 1293out_alloc:1294 unregister_chrdev_region(IB_UVERBS_BASE_DEV,1295 IB_UVERBS_NUM_FIXED_MINOR);1296 1297out:1298 return ret;1299}1300 1301static void __exit ib_uverbs_cleanup(void)1302{1303 ib_unregister_client(&uverbs_client);1304 class_unregister(&uverbs_class);1305 unregister_chrdev_region(IB_UVERBS_BASE_DEV,1306 IB_UVERBS_NUM_FIXED_MINOR);1307 unregister_chrdev_region(dynamic_uverbs_dev,1308 IB_UVERBS_NUM_DYNAMIC_MINOR);1309 mmu_notifier_synchronize();1310}1311 1312module_init(ib_uverbs_init);1313module_exit(ib_uverbs_cleanup);1314