diff options
Diffstat (limited to 'drivers/infiniband/core/uverbs_main.c')
| -rw-r--r-- | drivers/infiniband/core/uverbs_main.c | 1315 |
1 files changed, 1315 insertions, 0 deletions
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c new file mode 100644 index 000000000..6fe825800 --- /dev/null +++ b/drivers/infiniband/core/uverbs_main.c @@ -0,0 +1,1315 @@ +/* + * Copyright (c) 2005 Topspin Communications. All rights reserved. + * Copyright (c) 2005, 2006 Cisco Systems. All rights reserved. + * Copyright (c) 2005 Mellanox Technologies. All rights reserved. + * Copyright (c) 2005 Voltaire, Inc. All rights reserved. + * Copyright (c) 2005 PathScale, Inc. All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/fs.h> +#include <linux/poll.h> +#include <linux/sched.h> +#include <linux/file.h> +#include <linux/cdev.h> +#include <linux/anon_inodes.h> +#include <linux/slab.h> +#include <linux/sched/mm.h> + +#include <linux/uaccess.h> + +#include <rdma/ib.h> +#include <rdma/uverbs_std_types.h> +#include <rdma/rdma_netlink.h> + +#include "uverbs.h" +#include "core_priv.h" +#include "rdma_core.h" + +MODULE_AUTHOR("Roland Dreier"); +MODULE_DESCRIPTION("InfiniBand userspace verbs access"); +MODULE_LICENSE("Dual BSD/GPL"); + +enum { + IB_UVERBS_MAJOR = 231, + IB_UVERBS_BASE_MINOR = 192, + IB_UVERBS_MAX_DEVICES = RDMA_MAX_PORTS, + IB_UVERBS_NUM_FIXED_MINOR = 32, + IB_UVERBS_NUM_DYNAMIC_MINOR = IB_UVERBS_MAX_DEVICES - IB_UVERBS_NUM_FIXED_MINOR, +}; + +#define IB_UVERBS_BASE_DEV MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR) + +static dev_t dynamic_uverbs_dev; +static struct class *uverbs_class; + +static DEFINE_IDA(uverbs_ida); +static int ib_uverbs_add_one(struct ib_device *device); +static void ib_uverbs_remove_one(struct ib_device *device, void *client_data); + +/* + * Must be called with the ufile->device->disassociate_srcu held, and the lock + * must be held until use of the ucontext is finished. + */ +struct ib_ucontext *ib_uverbs_get_ucontext_file(struct ib_uverbs_file *ufile) +{ + /* + * We do not hold the hw_destroy_rwsem lock for this flow, instead + * srcu is used. It does not matter if someone races this with + * get_context, we get NULL or valid ucontext. + */ + struct ib_ucontext *ucontext = smp_load_acquire(&ufile->ucontext); + + if (!srcu_dereference(ufile->device->ib_dev, + &ufile->device->disassociate_srcu)) + return ERR_PTR(-EIO); + + if (!ucontext) + return ERR_PTR(-EINVAL); + + return ucontext; +} +EXPORT_SYMBOL(ib_uverbs_get_ucontext_file); + +int uverbs_dealloc_mw(struct ib_mw *mw) +{ + struct ib_pd *pd = mw->pd; + int ret; + + ret = mw->device->ops.dealloc_mw(mw); + if (ret) + return ret; + + atomic_dec(&pd->usecnt); + kfree(mw); + return ret; +} + +static void ib_uverbs_release_dev(struct device *device) +{ + struct ib_uverbs_device *dev = + container_of(device, struct ib_uverbs_device, dev); + + uverbs_destroy_api(dev->uapi); + cleanup_srcu_struct(&dev->disassociate_srcu); + mutex_destroy(&dev->lists_mutex); + mutex_destroy(&dev->xrcd_tree_mutex); + kfree(dev); +} + +void ib_uverbs_release_ucq(struct ib_uverbs_completion_event_file *ev_file, + struct ib_ucq_object *uobj) +{ + struct ib_uverbs_event *evt, *tmp; + + if (ev_file) { + spin_lock_irq(&ev_file->ev_queue.lock); + list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) { + list_del(&evt->list); + kfree(evt); + } + spin_unlock_irq(&ev_file->ev_queue.lock); + + uverbs_uobject_put(&ev_file->uobj); + } + + ib_uverbs_release_uevent(&uobj->uevent); +} + +void ib_uverbs_release_uevent(struct ib_uevent_object *uobj) +{ + struct ib_uverbs_async_event_file *async_file = uobj->event_file; + struct ib_uverbs_event *evt, *tmp; + + if (!async_file) + return; + + spin_lock_irq(&async_file->ev_queue.lock); + list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) { + list_del(&evt->list); + kfree(evt); + } + spin_unlock_irq(&async_file->ev_queue.lock); + uverbs_uobject_put(&async_file->uobj); +} + +void ib_uverbs_detach_umcast(struct ib_qp *qp, + struct ib_uqp_object *uobj) +{ + struct ib_uverbs_mcast_entry *mcast, *tmp; + + list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) { + ib_detach_mcast(qp, &mcast->gid, mcast->lid); + list_del(&mcast->list); + kfree(mcast); + } +} + +static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev) +{ + complete(&dev->comp); +} + +void ib_uverbs_release_file(struct kref *ref) +{ + struct ib_uverbs_file *file = + container_of(ref, struct ib_uverbs_file, ref); + struct ib_device *ib_dev; + int srcu_key; + + release_ufile_idr_uobject(file); + + srcu_key = srcu_read_lock(&file->device->disassociate_srcu); + ib_dev = srcu_dereference(file->device->ib_dev, + &file->device->disassociate_srcu); + if (ib_dev && !ib_dev->ops.disassociate_ucontext) + module_put(ib_dev->ops.owner); + srcu_read_unlock(&file->device->disassociate_srcu, srcu_key); + + if (refcount_dec_and_test(&file->device->refcount)) + ib_uverbs_comp_dev(file->device); + + if (file->default_async_file) + uverbs_uobject_put(&file->default_async_file->uobj); + put_device(&file->device->dev); + + if (file->disassociate_page) + __free_pages(file->disassociate_page, 0); + mutex_destroy(&file->umap_lock); + mutex_destroy(&file->ucontext_lock); + kfree(file); +} + +static ssize_t ib_uverbs_event_read(struct ib_uverbs_event_queue *ev_queue, + struct file *filp, char __user *buf, + size_t count, loff_t *pos, + size_t eventsz) +{ + struct ib_uverbs_event *event; + int ret = 0; + + spin_lock_irq(&ev_queue->lock); + + while (list_empty(&ev_queue->event_list)) { + if (ev_queue->is_closed) { + spin_unlock_irq(&ev_queue->lock); + return -EIO; + } + + spin_unlock_irq(&ev_queue->lock); + if (filp->f_flags & O_NONBLOCK) + return -EAGAIN; + + if (wait_event_interruptible(ev_queue->poll_wait, + (!list_empty(&ev_queue->event_list) || + ev_queue->is_closed))) + return -ERESTARTSYS; + + spin_lock_irq(&ev_queue->lock); + } + + event = list_entry(ev_queue->event_list.next, struct ib_uverbs_event, list); + + if (eventsz > count) { + ret = -EINVAL; + event = NULL; + } else { + list_del(ev_queue->event_list.next); + if (event->counter) { + ++(*event->counter); + list_del(&event->obj_list); + } + } + + spin_unlock_irq(&ev_queue->lock); + + if (event) { + if (copy_to_user(buf, event, eventsz)) + ret = -EFAULT; + else + ret = eventsz; + } + + kfree(event); + + return ret; +} + +static ssize_t ib_uverbs_async_event_read(struct file *filp, char __user *buf, + size_t count, loff_t *pos) +{ + struct ib_uverbs_async_event_file *file = filp->private_data; + + return ib_uverbs_event_read(&file->ev_queue, filp, buf, count, pos, + sizeof(struct ib_uverbs_async_event_desc)); +} + +static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf, + size_t count, loff_t *pos) +{ + struct ib_uverbs_completion_event_file *comp_ev_file = + filp->private_data; + + return ib_uverbs_event_read(&comp_ev_file->ev_queue, filp, buf, count, + pos, + sizeof(struct ib_uverbs_comp_event_desc)); +} + +static __poll_t ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue, + struct file *filp, + struct poll_table_struct *wait) +{ + __poll_t pollflags = 0; + + poll_wait(filp, &ev_queue->poll_wait, wait); + + spin_lock_irq(&ev_queue->lock); + if (!list_empty(&ev_queue->event_list)) + pollflags = EPOLLIN | EPOLLRDNORM; + else if (ev_queue->is_closed) + pollflags = EPOLLERR; + spin_unlock_irq(&ev_queue->lock); + + return pollflags; +} + +static __poll_t ib_uverbs_async_event_poll(struct file *filp, + struct poll_table_struct *wait) +{ + struct ib_uverbs_async_event_file *file = filp->private_data; + + return ib_uverbs_event_poll(&file->ev_queue, filp, wait); +} + +static __poll_t ib_uverbs_comp_event_poll(struct file *filp, + struct poll_table_struct *wait) +{ + struct ib_uverbs_completion_event_file *comp_ev_file = + filp->private_data; + + return ib_uverbs_event_poll(&comp_ev_file->ev_queue, filp, wait); +} + +static int ib_uverbs_async_event_fasync(int fd, struct file *filp, int on) +{ + struct ib_uverbs_async_event_file *file = filp->private_data; + + return fasync_helper(fd, filp, on, &file->ev_queue.async_queue); +} + +static int ib_uverbs_comp_event_fasync(int fd, struct file *filp, int on) +{ + struct ib_uverbs_completion_event_file *comp_ev_file = + filp->private_data; + + return fasync_helper(fd, filp, on, &comp_ev_file->ev_queue.async_queue); +} + +const struct file_operations uverbs_event_fops = { + .owner = THIS_MODULE, + .read = ib_uverbs_comp_event_read, + .poll = ib_uverbs_comp_event_poll, + .release = uverbs_uobject_fd_release, + .fasync = ib_uverbs_comp_event_fasync, + .llseek = no_llseek, +}; + +const struct file_operations uverbs_async_event_fops = { + .owner = THIS_MODULE, + .read = ib_uverbs_async_event_read, + .poll = ib_uverbs_async_event_poll, + .release = uverbs_async_event_release, + .fasync = ib_uverbs_async_event_fasync, + .llseek = no_llseek, +}; + +void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context) +{ + struct ib_uverbs_event_queue *ev_queue = cq_context; + struct ib_ucq_object *uobj; + struct ib_uverbs_event *entry; + unsigned long flags; + + if (!ev_queue) + return; + + spin_lock_irqsave(&ev_queue->lock, flags); + if (ev_queue->is_closed) { + spin_unlock_irqrestore(&ev_queue->lock, flags); + return; + } + + entry = kmalloc(sizeof(*entry), GFP_ATOMIC); + if (!entry) { + spin_unlock_irqrestore(&ev_queue->lock, flags); + return; + } + + uobj = cq->uobject; + + entry->desc.comp.cq_handle = cq->uobject->uevent.uobject.user_handle; + entry->counter = &uobj->comp_events_reported; + + list_add_tail(&entry->list, &ev_queue->event_list); + list_add_tail(&entry->obj_list, &uobj->comp_list); + spin_unlock_irqrestore(&ev_queue->lock, flags); + + wake_up_interruptible(&ev_queue->poll_wait); + kill_fasync(&ev_queue->async_queue, SIGIO, POLL_IN); +} + +void ib_uverbs_async_handler(struct ib_uverbs_async_event_file *async_file, + __u64 element, __u64 event, + struct list_head *obj_list, u32 *counter) +{ + struct ib_uverbs_event *entry; + unsigned long flags; + + if (!async_file) + return; + + spin_lock_irqsave(&async_file->ev_queue.lock, flags); + if (async_file->ev_queue.is_closed) { + spin_unlock_irqrestore(&async_file->ev_queue.lock, flags); + return; + } + + entry = kmalloc(sizeof(*entry), GFP_ATOMIC); + if (!entry) { + spin_unlock_irqrestore(&async_file->ev_queue.lock, flags); + return; + } + + entry->desc.async.element = element; + entry->desc.async.event_type = event; + entry->desc.async.reserved = 0; + entry->counter = counter; + + list_add_tail(&entry->list, &async_file->ev_queue.event_list); + if (obj_list) + list_add_tail(&entry->obj_list, obj_list); + spin_unlock_irqrestore(&async_file->ev_queue.lock, flags); + + wake_up_interruptible(&async_file->ev_queue.poll_wait); + kill_fasync(&async_file->ev_queue.async_queue, SIGIO, POLL_IN); +} + +static void uverbs_uobj_event(struct ib_uevent_object *eobj, + struct ib_event *event) +{ + ib_uverbs_async_handler(eobj->event_file, + eobj->uobject.user_handle, event->event, + &eobj->event_list, &eobj->events_reported); +} + +void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr) +{ + uverbs_uobj_event(&event->element.cq->uobject->uevent, event); +} + +void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr) +{ + /* for XRC target qp's, check that qp is live */ + if (!event->element.qp->uobject) + return; + + uverbs_uobj_event(&event->element.qp->uobject->uevent, event); +} + +void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr) +{ + uverbs_uobj_event(&event->element.wq->uobject->uevent, event); +} + +void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr) +{ + uverbs_uobj_event(&event->element.srq->uobject->uevent, event); +} + +static void ib_uverbs_event_handler(struct ib_event_handler *handler, + struct ib_event *event) +{ + ib_uverbs_async_handler( + container_of(handler, struct ib_uverbs_async_event_file, + event_handler), + event->element.port_num, event->event, NULL, NULL); +} + +void ib_uverbs_init_event_queue(struct ib_uverbs_event_queue *ev_queue) +{ + spin_lock_init(&ev_queue->lock); + INIT_LIST_HEAD(&ev_queue->event_list); + init_waitqueue_head(&ev_queue->poll_wait); + ev_queue->is_closed = 0; + ev_queue->async_queue = NULL; +} + +void ib_uverbs_init_async_event_file( + struct ib_uverbs_async_event_file *async_file) +{ + struct ib_uverbs_file *uverbs_file = async_file->uobj.ufile; + struct ib_device *ib_dev = async_file->uobj.context->device; + + ib_uverbs_init_event_queue(&async_file->ev_queue); + + /* The first async_event_file becomes the default one for the file. */ + mutex_lock(&uverbs_file->ucontext_lock); + if (!uverbs_file->default_async_file) { + /* Pairs with the put in ib_uverbs_release_file */ + uverbs_uobject_get(&async_file->uobj); + smp_store_release(&uverbs_file->default_async_file, async_file); + } + mutex_unlock(&uverbs_file->ucontext_lock); + + INIT_IB_EVENT_HANDLER(&async_file->event_handler, ib_dev, + ib_uverbs_event_handler); + ib_register_event_handler(&async_file->event_handler); +} + +static ssize_t verify_hdr(struct ib_uverbs_cmd_hdr *hdr, + struct ib_uverbs_ex_cmd_hdr *ex_hdr, size_t count, + const struct uverbs_api_write_method *method_elm) +{ + if (method_elm->is_ex) { + count -= sizeof(*hdr) + sizeof(*ex_hdr); + + if ((hdr->in_words + ex_hdr->provider_in_words) * 8 != count) + return -EINVAL; + + if (hdr->in_words * 8 < method_elm->req_size) + return -ENOSPC; + + if (ex_hdr->cmd_hdr_reserved) + return -EINVAL; + + if (ex_hdr->response) { + if (!hdr->out_words && !ex_hdr->provider_out_words) + return -EINVAL; + + if (hdr->out_words * 8 < method_elm->resp_size) + return -ENOSPC; + + if (!access_ok(u64_to_user_ptr(ex_hdr->response), + (hdr->out_words + ex_hdr->provider_out_words) * 8)) + return -EFAULT; + } else { + if (hdr->out_words || ex_hdr->provider_out_words) + return -EINVAL; + } + + return 0; + } + + /* not extended command */ + if (hdr->in_words * 4 != count) + return -EINVAL; + + if (count < method_elm->req_size + sizeof(*hdr)) { + /* + * rdma-core v18 and v19 have a bug where they send DESTROY_CQ + * with a 16 byte write instead of 24. Old kernels didn't + * check the size so they allowed this. Now that the size is + * checked provide a compatibility work around to not break + * those userspaces. + */ + if (hdr->command == IB_USER_VERBS_CMD_DESTROY_CQ && + count == 16) { + hdr->in_words = 6; + return 0; + } + return -ENOSPC; + } + if (hdr->out_words * 4 < method_elm->resp_size) + return -ENOSPC; + + return 0; +} + +static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf, + size_t count, loff_t *pos) +{ + struct ib_uverbs_file *file = filp->private_data; + const struct uverbs_api_write_method *method_elm; + struct uverbs_api *uapi = file->device->uapi; + struct ib_uverbs_ex_cmd_hdr ex_hdr; + struct ib_uverbs_cmd_hdr hdr; + struct uverbs_attr_bundle bundle; + int srcu_key; + ssize_t ret; + + if (!ib_safe_file_access(filp)) { + pr_err_once("uverbs_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n", + task_tgid_vnr(current), current->comm); + return -EACCES; + } + + if (count < sizeof(hdr)) + return -EINVAL; + + if (copy_from_user(&hdr, buf, sizeof(hdr))) + return -EFAULT; + + method_elm = uapi_get_method(uapi, hdr.command); + if (IS_ERR(method_elm)) + return PTR_ERR(method_elm); + + if (method_elm->is_ex) { + if (count < (sizeof(hdr) + sizeof(ex_hdr))) + return -EINVAL; + if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) + return -EFAULT; + } + + ret = verify_hdr(&hdr, &ex_hdr, count, method_elm); + if (ret) + return ret; + + srcu_key = srcu_read_lock(&file->device->disassociate_srcu); + + buf += sizeof(hdr); + + memset(bundle.attr_present, 0, sizeof(bundle.attr_present)); + bundle.ufile = file; + bundle.context = NULL; /* only valid if bundle has uobject */ + bundle.uobject = NULL; + if (!method_elm->is_ex) { + size_t in_len = hdr.in_words * 4 - sizeof(hdr); + size_t out_len = hdr.out_words * 4; + u64 response = 0; + + if (method_elm->has_udata) { + bundle.driver_udata.inlen = + in_len - method_elm->req_size; + in_len = method_elm->req_size; + if (bundle.driver_udata.inlen) + bundle.driver_udata.inbuf = buf + in_len; + else + bundle.driver_udata.inbuf = NULL; + } else { + memset(&bundle.driver_udata, 0, + sizeof(bundle.driver_udata)); + } + + if (method_elm->has_resp) { + /* + * The macros check that if has_resp is set + * then the command request structure starts + * with a '__aligned u64 response' member. + */ + ret = get_user(response, (const u64 __user *)buf); + if (ret) + goto out_unlock; + + if (method_elm->has_udata) { + bundle.driver_udata.outlen = + out_len - method_elm->resp_size; + out_len = method_elm->resp_size; + if (bundle.driver_udata.outlen) + bundle.driver_udata.outbuf = + u64_to_user_ptr(response + + out_len); + else + bundle.driver_udata.outbuf = NULL; + } + } else { + bundle.driver_udata.outlen = 0; + bundle.driver_udata.outbuf = NULL; + } + + ib_uverbs_init_udata_buf_or_null( + &bundle.ucore, buf, u64_to_user_ptr(response), + in_len, out_len); + } else { + buf += sizeof(ex_hdr); + + ib_uverbs_init_udata_buf_or_null(&bundle.ucore, buf, + u64_to_user_ptr(ex_hdr.response), + hdr.in_words * 8, hdr.out_words * 8); + + ib_uverbs_init_udata_buf_or_null( + &bundle.driver_udata, buf + bundle.ucore.inlen, + u64_to_user_ptr(ex_hdr.response) + bundle.ucore.outlen, + ex_hdr.provider_in_words * 8, + ex_hdr.provider_out_words * 8); + + } + + ret = method_elm->handler(&bundle); + if (bundle.uobject) + uverbs_finalize_object(bundle.uobject, UVERBS_ACCESS_NEW, true, + !ret, &bundle); +out_unlock: + srcu_read_unlock(&file->device->disassociate_srcu, srcu_key); + return (ret) ? : count; +} + +static const struct vm_operations_struct rdma_umap_ops; + +static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct ib_uverbs_file *file = filp->private_data; + struct ib_ucontext *ucontext; + int ret = 0; + int srcu_key; + + srcu_key = srcu_read_lock(&file->device->disassociate_srcu); + ucontext = ib_uverbs_get_ucontext_file(file); + if (IS_ERR(ucontext)) { + ret = PTR_ERR(ucontext); + goto out; + } + vma->vm_ops = &rdma_umap_ops; + ret = ucontext->device->ops.mmap(ucontext, vma); +out: + srcu_read_unlock(&file->device->disassociate_srcu, srcu_key); + return ret; +} + +/* + * The VMA has been dup'd, initialize the vm_private_data with a new tracking + * struct + */ +static void rdma_umap_open(struct vm_area_struct *vma) +{ + struct ib_uverbs_file *ufile = vma->vm_file->private_data; + struct rdma_umap_priv *opriv = vma->vm_private_data; + struct rdma_umap_priv *priv; + + if (!opriv) + return; + + /* We are racing with disassociation */ + if (!down_read_trylock(&ufile->hw_destroy_rwsem)) + goto out_zap; + /* + * Disassociation already completed, the VMA should already be zapped. + */ + if (!ufile->ucontext) + goto out_unlock; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + goto out_unlock; + rdma_umap_priv_init(priv, vma, opriv->entry); + + up_read(&ufile->hw_destroy_rwsem); + return; + +out_unlock: + up_read(&ufile->hw_destroy_rwsem); +out_zap: + /* + * We can't allow the VMA to be created with the actual IO pages, that + * would break our API contract, and it can't be stopped at this + * point, so zap it. + */ + vma->vm_private_data = NULL; + zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start); +} + +static void rdma_umap_close(struct vm_area_struct *vma) +{ + struct ib_uverbs_file *ufile = vma->vm_file->private_data; + struct rdma_umap_priv *priv = vma->vm_private_data; + + if (!priv) + return; + + /* + * The vma holds a reference on the struct file that created it, which + * in turn means that the ib_uverbs_file is guaranteed to exist at + * this point. + */ + mutex_lock(&ufile->umap_lock); + if (priv->entry) + rdma_user_mmap_entry_put(priv->entry); + + list_del(&priv->list); + mutex_unlock(&ufile->umap_lock); + kfree(priv); +} + +/* + * Once the zap_vma_ptes has been called touches to the VMA will come here and + * we return a dummy writable zero page for all the pfns. + */ +static vm_fault_t rdma_umap_fault(struct vm_fault *vmf) +{ + struct ib_uverbs_file *ufile = vmf->vma->vm_file->private_data; + struct rdma_umap_priv *priv = vmf->vma->vm_private_data; + vm_fault_t ret = 0; + + if (!priv) + return VM_FAULT_SIGBUS; + + /* Read only pages can just use the system zero page. */ + if (!(vmf->vma->vm_flags & (VM_WRITE | VM_MAYWRITE))) { + vmf->page = ZERO_PAGE(vmf->address); + get_page(vmf->page); + return 0; + } + + mutex_lock(&ufile->umap_lock); + if (!ufile->disassociate_page) + ufile->disassociate_page = + alloc_pages(vmf->gfp_mask | __GFP_ZERO, 0); + + if (ufile->disassociate_page) { + /* + * This VMA is forced to always be shared so this doesn't have + * to worry about COW. + */ + vmf->page = ufile->disassociate_page; + get_page(vmf->page); + } else { + ret = VM_FAULT_SIGBUS; + } + mutex_unlock(&ufile->umap_lock); + + return ret; +} + +static const struct vm_operations_struct rdma_umap_ops = { + .open = rdma_umap_open, + .close = rdma_umap_close, + .fault = rdma_umap_fault, +}; + +void uverbs_user_mmap_disassociate(struct ib_uverbs_file *ufile) +{ + struct rdma_umap_priv *priv, *next_priv; + + lockdep_assert_held(&ufile->hw_destroy_rwsem); + + while (1) { + struct mm_struct *mm = NULL; + + /* Get an arbitrary mm pointer that hasn't been cleaned yet */ + mutex_lock(&ufile->umap_lock); + while (!list_empty(&ufile->umaps)) { + int ret; + + priv = list_first_entry(&ufile->umaps, + struct rdma_umap_priv, list); + mm = priv->vma->vm_mm; + ret = mmget_not_zero(mm); + if (!ret) { + list_del_init(&priv->list); + if (priv->entry) { + rdma_user_mmap_entry_put(priv->entry); + priv->entry = NULL; + } + mm = NULL; + continue; + } + break; + } + mutex_unlock(&ufile->umap_lock); + if (!mm) + return; + + /* + * The umap_lock is nested under mmap_lock since it used within + * the vma_ops callbacks, so we have to clean the list one mm + * at a time to get the lock ordering right. Typically there + * will only be one mm, so no big deal. + */ + mmap_read_lock(mm); + mutex_lock(&ufile->umap_lock); + list_for_each_entry_safe (priv, next_priv, &ufile->umaps, + list) { + struct vm_area_struct *vma = priv->vma; + + if (vma->vm_mm != mm) + continue; + list_del_init(&priv->list); + + zap_vma_ptes(vma, vma->vm_start, + vma->vm_end - vma->vm_start); + + if (priv->entry) { + rdma_user_mmap_entry_put(priv->entry); + priv->entry = NULL; + } + } + mutex_unlock(&ufile->umap_lock); + mmap_read_unlock(mm); + mmput(mm); + } +} + +/* + * ib_uverbs_open() does not need the BKL: + * + * - the ib_uverbs_device structures are properly reference counted and + * everything else is purely local to the file being created, so + * races against other open calls are not a problem; + * - there is no ioctl method to race against; + * - the open method will either immediately run -ENXIO, or all + * required initialization will be done. + */ +static int ib_uverbs_open(struct inode *inode, struct file *filp) +{ + struct ib_uverbs_device *dev; + struct ib_uverbs_file *file; + struct ib_device *ib_dev; + int ret; + int module_dependent; + int srcu_key; + + dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev); + if (!refcount_inc_not_zero(&dev->refcount)) + return -ENXIO; + + get_device(&dev->dev); + srcu_key = srcu_read_lock(&dev->disassociate_srcu); + mutex_lock(&dev->lists_mutex); + ib_dev = srcu_dereference(dev->ib_dev, + &dev->disassociate_srcu); + if (!ib_dev) { + ret = -EIO; + goto err; + } + + if (!rdma_dev_access_netns(ib_dev, current->nsproxy->net_ns)) { + ret = -EPERM; + goto err; + } + + /* In case IB device supports disassociate ucontext, there is no hard + * dependency between uverbs device and its low level device. + */ + module_dependent = !(ib_dev->ops.disassociate_ucontext); + + if (module_dependent) { + if (!try_module_get(ib_dev->ops.owner)) { + ret = -ENODEV; + goto err; + } + } + + file = kzalloc(sizeof(*file), GFP_KERNEL); + if (!file) { + ret = -ENOMEM; + if (module_dependent) + goto err_module; + + goto err; + } + + file->device = dev; + kref_init(&file->ref); + mutex_init(&file->ucontext_lock); + + spin_lock_init(&file->uobjects_lock); + INIT_LIST_HEAD(&file->uobjects); + init_rwsem(&file->hw_destroy_rwsem); + mutex_init(&file->umap_lock); + INIT_LIST_HEAD(&file->umaps); + + filp->private_data = file; + list_add_tail(&file->list, &dev->uverbs_file_list); + mutex_unlock(&dev->lists_mutex); + srcu_read_unlock(&dev->disassociate_srcu, srcu_key); + + setup_ufile_idr_uobject(file); + + return stream_open(inode, filp); + +err_module: + module_put(ib_dev->ops.owner); + +err: + mutex_unlock(&dev->lists_mutex); + srcu_read_unlock(&dev->disassociate_srcu, srcu_key); + if (refcount_dec_and_test(&dev->refcount)) + ib_uverbs_comp_dev(dev); + + put_device(&dev->dev); + return ret; +} + +static int ib_uverbs_close(struct inode *inode, struct file *filp) +{ + struct ib_uverbs_file *file = filp->private_data; + + uverbs_destroy_ufile_hw(file, RDMA_REMOVE_CLOSE); + + mutex_lock(&file->device->lists_mutex); + list_del_init(&file->list); + mutex_unlock(&file->device->lists_mutex); + + kref_put(&file->ref, ib_uverbs_release_file); + + return 0; +} + +static const struct file_operations uverbs_fops = { + .owner = THIS_MODULE, + .write = ib_uverbs_write, + .open = ib_uverbs_open, + .release = ib_uverbs_close, + .llseek = no_llseek, + .unlocked_ioctl = ib_uverbs_ioctl, + .compat_ioctl = compat_ptr_ioctl, +}; + +static const struct file_operations uverbs_mmap_fops = { + .owner = THIS_MODULE, + .write = ib_uverbs_write, + .mmap = ib_uverbs_mmap, + .open = ib_uverbs_open, + .release = ib_uverbs_close, + .llseek = no_llseek, + .unlocked_ioctl = ib_uverbs_ioctl, + .compat_ioctl = compat_ptr_ioctl, +}; + +static int ib_uverbs_get_nl_info(struct ib_device *ibdev, void *client_data, + struct ib_client_nl_info *res) +{ + struct ib_uverbs_device *uverbs_dev = client_data; + int ret; + + if (res->port != -1) + return -EINVAL; + + res->abi = ibdev->ops.uverbs_abi_ver; + res->cdev = &uverbs_dev->dev; + + /* + * To support DRIVER_ID binding in userspace some of the driver need + * upgrading to expose their PCI dependent revision information + * through get_context instead of relying on modalias matching. When + * the drivers are fixed they can drop this flag. + */ + if (!ibdev->ops.uverbs_no_driver_id_binding) { + ret = nla_put_u32(res->nl_msg, RDMA_NLDEV_ATTR_UVERBS_DRIVER_ID, + ibdev->ops.driver_id); + if (ret) + return ret; + } + return 0; +} + +static struct ib_client uverbs_client = { + .name = "uverbs", + .no_kverbs_req = true, + .add = ib_uverbs_add_one, + .remove = ib_uverbs_remove_one, + .get_nl_info = ib_uverbs_get_nl_info, +}; +MODULE_ALIAS_RDMA_CLIENT("uverbs"); + +static ssize_t ibdev_show(struct device *device, struct device_attribute *attr, + char *buf) +{ + struct ib_uverbs_device *dev = + container_of(device, struct ib_uverbs_device, dev); + int ret = -ENODEV; + int srcu_key; + struct ib_device *ib_dev; + + srcu_key = srcu_read_lock(&dev->disassociate_srcu); + ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu); + if (ib_dev) + ret = sysfs_emit(buf, "%s\n", dev_name(&ib_dev->dev)); + srcu_read_unlock(&dev->disassociate_srcu, srcu_key); + + return ret; +} +static DEVICE_ATTR_RO(ibdev); + +static ssize_t abi_version_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct ib_uverbs_device *dev = + container_of(device, struct ib_uverbs_device, dev); + int ret = -ENODEV; + int srcu_key; + struct ib_device *ib_dev; + + srcu_key = srcu_read_lock(&dev->disassociate_srcu); + ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu); + if (ib_dev) + ret = sysfs_emit(buf, "%u\n", ib_dev->ops.uverbs_abi_ver); + srcu_read_unlock(&dev->disassociate_srcu, srcu_key); + + return ret; +} +static DEVICE_ATTR_RO(abi_version); + +static struct attribute *ib_dev_attrs[] = { + &dev_attr_abi_version.attr, + &dev_attr_ibdev.attr, + NULL, +}; + +static const struct attribute_group dev_attr_group = { + .attrs = ib_dev_attrs, +}; + +static CLASS_ATTR_STRING(abi_version, S_IRUGO, + __stringify(IB_USER_VERBS_ABI_VERSION)); + +static int ib_uverbs_create_uapi(struct ib_device *device, + struct ib_uverbs_device *uverbs_dev) +{ + struct uverbs_api *uapi; + + uapi = uverbs_alloc_api(device); + if (IS_ERR(uapi)) + return PTR_ERR(uapi); + + uverbs_dev->uapi = uapi; + return 0; +} + +static int ib_uverbs_add_one(struct ib_device *device) +{ + int devnum; + dev_t base; + struct ib_uverbs_device *uverbs_dev; + int ret; + + if (!device->ops.alloc_ucontext) + return -EOPNOTSUPP; + + uverbs_dev = kzalloc(sizeof(*uverbs_dev), GFP_KERNEL); + if (!uverbs_dev) + return -ENOMEM; + + ret = init_srcu_struct(&uverbs_dev->disassociate_srcu); + if (ret) { + kfree(uverbs_dev); + return -ENOMEM; + } + + device_initialize(&uverbs_dev->dev); + uverbs_dev->dev.class = uverbs_class; + uverbs_dev->dev.parent = device->dev.parent; + uverbs_dev->dev.release = ib_uverbs_release_dev; + uverbs_dev->groups[0] = &dev_attr_group; + uverbs_dev->dev.groups = uverbs_dev->groups; + refcount_set(&uverbs_dev->refcount, 1); + init_completion(&uverbs_dev->comp); + uverbs_dev->xrcd_tree = RB_ROOT; + mutex_init(&uverbs_dev->xrcd_tree_mutex); + mutex_init(&uverbs_dev->lists_mutex); + INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list); + rcu_assign_pointer(uverbs_dev->ib_dev, device); + uverbs_dev->num_comp_vectors = device->num_comp_vectors; + + devnum = ida_alloc_max(&uverbs_ida, IB_UVERBS_MAX_DEVICES - 1, + GFP_KERNEL); + if (devnum < 0) { + ret = -ENOMEM; + goto err; + } + uverbs_dev->devnum = devnum; + if (devnum >= IB_UVERBS_NUM_FIXED_MINOR) + base = dynamic_uverbs_dev + devnum - IB_UVERBS_NUM_FIXED_MINOR; + else + base = IB_UVERBS_BASE_DEV + devnum; + + ret = ib_uverbs_create_uapi(device, uverbs_dev); + if (ret) + goto err_uapi; + + uverbs_dev->dev.devt = base; + dev_set_name(&uverbs_dev->dev, "uverbs%d", uverbs_dev->devnum); + + cdev_init(&uverbs_dev->cdev, + device->ops.mmap ? &uverbs_mmap_fops : &uverbs_fops); + uverbs_dev->cdev.owner = THIS_MODULE; + + ret = cdev_device_add(&uverbs_dev->cdev, &uverbs_dev->dev); + if (ret) + goto err_uapi; + + ib_set_client_data(device, &uverbs_client, uverbs_dev); + return 0; + +err_uapi: + ida_free(&uverbs_ida, devnum); +err: + if (refcount_dec_and_test(&uverbs_dev->refcount)) + ib_uverbs_comp_dev(uverbs_dev); + wait_for_completion(&uverbs_dev->comp); + put_device(&uverbs_dev->dev); + return ret; +} + +static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev, + struct ib_device *ib_dev) +{ + struct ib_uverbs_file *file; + + /* Pending running commands to terminate */ + uverbs_disassociate_api_pre(uverbs_dev); + + mutex_lock(&uverbs_dev->lists_mutex); + while (!list_empty(&uverbs_dev->uverbs_file_list)) { + file = list_first_entry(&uverbs_dev->uverbs_file_list, + struct ib_uverbs_file, list); + list_del_init(&file->list); + kref_get(&file->ref); + + /* We must release the mutex before going ahead and calling + * uverbs_cleanup_ufile, as it might end up indirectly calling + * uverbs_close, for example due to freeing the resources (e.g + * mmput). + */ + mutex_unlock(&uverbs_dev->lists_mutex); + + uverbs_destroy_ufile_hw(file, RDMA_REMOVE_DRIVER_REMOVE); + kref_put(&file->ref, ib_uverbs_release_file); + + mutex_lock(&uverbs_dev->lists_mutex); + } + mutex_unlock(&uverbs_dev->lists_mutex); + + uverbs_disassociate_api(uverbs_dev->uapi); +} + +static void ib_uverbs_remove_one(struct ib_device *device, void *client_data) +{ + struct ib_uverbs_device *uverbs_dev = client_data; + int wait_clients = 1; + + cdev_device_del(&uverbs_dev->cdev, &uverbs_dev->dev); + ida_free(&uverbs_ida, uverbs_dev->devnum); + + if (device->ops.disassociate_ucontext) { + /* We disassociate HW resources and immediately return. + * Userspace will see a EIO errno for all future access. + * Upon returning, ib_device may be freed internally and is not + * valid any more. + * uverbs_device is still available until all clients close + * their files, then the uverbs device ref count will be zero + * and its resources will be freed. + * Note: At this point no more files can be opened since the + * cdev was deleted, however active clients can still issue + * commands and close their open files. + */ + ib_uverbs_free_hw_resources(uverbs_dev, device); + wait_clients = 0; + } + + if (refcount_dec_and_test(&uverbs_dev->refcount)) + ib_uverbs_comp_dev(uverbs_dev); + if (wait_clients) + wait_for_completion(&uverbs_dev->comp); + + put_device(&uverbs_dev->dev); +} + +static char *uverbs_devnode(struct device *dev, umode_t *mode) +{ + if (mode) + *mode = 0666; + return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev)); +} + +static int __init ib_uverbs_init(void) +{ + int ret; + + ret = register_chrdev_region(IB_UVERBS_BASE_DEV, + IB_UVERBS_NUM_FIXED_MINOR, + "infiniband_verbs"); + if (ret) { + pr_err("user_verbs: couldn't register device number\n"); + goto out; + } + + ret = alloc_chrdev_region(&dynamic_uverbs_dev, 0, + IB_UVERBS_NUM_DYNAMIC_MINOR, + "infiniband_verbs"); + if (ret) { + pr_err("couldn't register dynamic device number\n"); + goto out_alloc; + } + + uverbs_class = class_create(THIS_MODULE, "infiniband_verbs"); + if (IS_ERR(uverbs_class)) { + ret = PTR_ERR(uverbs_class); + pr_err("user_verbs: couldn't create class infiniband_verbs\n"); + goto out_chrdev; + } + + uverbs_class->devnode = uverbs_devnode; + + ret = class_create_file(uverbs_class, &class_attr_abi_version.attr); + if (ret) { + pr_err("user_verbs: couldn't create abi_version attribute\n"); + goto out_class; + } + + ret = ib_register_client(&uverbs_client); + if (ret) { + pr_err("user_verbs: couldn't register client\n"); + goto out_class; + } + + return 0; + +out_class: + class_destroy(uverbs_class); + +out_chrdev: + unregister_chrdev_region(dynamic_uverbs_dev, + IB_UVERBS_NUM_DYNAMIC_MINOR); + +out_alloc: + unregister_chrdev_region(IB_UVERBS_BASE_DEV, + IB_UVERBS_NUM_FIXED_MINOR); + +out: + return ret; +} + +static void __exit ib_uverbs_cleanup(void) +{ + ib_unregister_client(&uverbs_client); + class_destroy(uverbs_class); + unregister_chrdev_region(IB_UVERBS_BASE_DEV, + IB_UVERBS_NUM_FIXED_MINOR); + unregister_chrdev_region(dynamic_uverbs_dev, + IB_UVERBS_NUM_DYNAMIC_MINOR); + mmu_notifier_synchronize(); +} + +module_init(ib_uverbs_init); +module_exit(ib_uverbs_cleanup); |