linux/linux-5.4.31/drivers/infiniband/core/uverbs_main.c

1495 lines
40 KiB
C

/*
* 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 void 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)
atomic_dec(&pd->usecnt);
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);
}
static void ib_uverbs_release_async_event_file(struct kref *ref)
{
struct ib_uverbs_async_event_file *file =
container_of(ref, struct ib_uverbs_async_event_file, ref);
kfree(file);
}
void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
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);
}
spin_lock_irq(&file->async_file->ev_queue.lock);
list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
list_del(&evt->list);
kfree(evt);
}
spin_unlock_irq(&file->async_file->ev_queue.lock);
}
void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
struct ib_uevent_object *uobj)
{
struct ib_uverbs_event *evt, *tmp;
spin_lock_irq(&file->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(&file->async_file->ev_queue.lock);
}
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 (atomic_dec_and_test(&file->device->refcount))
ib_uverbs_comp_dev(file->device);
if (file->async_file)
kref_put(&file->async_file->ref,
ib_uverbs_release_async_event_file);
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)) {
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);
/* If device was disassociated and no event exists set an error */
if (list_empty(&ev_queue->event_list) && ev_queue->is_closed) {
spin_unlock_irq(&ev_queue->lock);
return -EIO;
}
}
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;
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);
}
static int ib_uverbs_async_event_close(struct inode *inode, struct file *filp)
{
struct ib_uverbs_async_event_file *file = filp->private_data;
struct ib_uverbs_file *uverbs_file = file->uverbs_file;
struct ib_uverbs_event *entry, *tmp;
int closed_already = 0;
mutex_lock(&uverbs_file->device->lists_mutex);
spin_lock_irq(&file->ev_queue.lock);
closed_already = file->ev_queue.is_closed;
file->ev_queue.is_closed = 1;
list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
if (entry->counter)
list_del(&entry->obj_list);
kfree(entry);
}
spin_unlock_irq(&file->ev_queue.lock);
if (!closed_already) {
list_del(&file->list);
ib_unregister_event_handler(&uverbs_file->event_handler);
}
mutex_unlock(&uverbs_file->device->lists_mutex);
kref_put(&uverbs_file->ref, ib_uverbs_release_file);
kref_put(&file->ref, ib_uverbs_release_async_event_file);
return 0;
}
static int ib_uverbs_comp_event_close(struct inode *inode, struct file *filp)
{
struct ib_uobject *uobj = filp->private_data;
struct ib_uverbs_completion_event_file *file = container_of(
uobj, struct ib_uverbs_completion_event_file, uobj);
struct ib_uverbs_event *entry, *tmp;
spin_lock_irq(&file->ev_queue.lock);
list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
if (entry->counter)
list_del(&entry->obj_list);
kfree(entry);
}
file->ev_queue.is_closed = 1;
spin_unlock_irq(&file->ev_queue.lock);
uverbs_close_fd(filp);
return 0;
}
const struct file_operations uverbs_event_fops = {
.owner = THIS_MODULE,
.read = ib_uverbs_comp_event_read,
.poll = ib_uverbs_comp_event_poll,
.release = ib_uverbs_comp_event_close,
.fasync = ib_uverbs_comp_event_fasync,
.llseek = no_llseek,
};
static const struct file_operations uverbs_async_event_fops = {
.owner = THIS_MODULE,
.read = ib_uverbs_async_event_read,
.poll = ib_uverbs_async_event_poll,
.release = ib_uverbs_async_event_close,
.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 = container_of(cq->uobject, struct ib_ucq_object, uobject);
entry->desc.comp.cq_handle = cq->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);
}
static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
__u64 element, __u64 event,
struct list_head *obj_list,
u32 *counter)
{
struct ib_uverbs_event *entry;
unsigned long flags;
spin_lock_irqsave(&file->async_file->ev_queue.lock, flags);
if (file->async_file->ev_queue.is_closed) {
spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
return;
}
entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
if (!entry) {
spin_unlock_irqrestore(&file->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, &file->async_file->ev_queue.event_list);
if (obj_list)
list_add_tail(&entry->obj_list, obj_list);
spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
wake_up_interruptible(&file->async_file->ev_queue.poll_wait);
kill_fasync(&file->async_file->ev_queue.async_queue, SIGIO, POLL_IN);
}
void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
{
struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
struct ib_ucq_object, uobject);
ib_uverbs_async_handler(uobj->uobject.ufile, uobj->uobject.user_handle,
event->event, &uobj->async_list,
&uobj->async_events_reported);
}
void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
{
struct ib_uevent_object *uobj;
/* for XRC target qp's, check that qp is live */
if (!event->element.qp->uobject)
return;
uobj = container_of(event->element.qp->uobject,
struct ib_uevent_object, uobject);
ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
event->event, &uobj->event_list,
&uobj->events_reported);
}
void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
{
struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
struct ib_uevent_object, uobject);
ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
event->event, &uobj->event_list,
&uobj->events_reported);
}
void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
{
struct ib_uevent_object *uobj;
uobj = container_of(event->element.srq->uobject,
struct ib_uevent_object, uobject);
ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
event->event, &uobj->event_list,
&uobj->events_reported);
}
void ib_uverbs_event_handler(struct ib_event_handler *handler,
struct ib_event *event)
{
struct ib_uverbs_file *file =
container_of(handler, struct ib_uverbs_file, event_handler);
ib_uverbs_async_handler(file, event->element.port_num, event->event,
NULL, NULL);
}
void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
{
kref_put(&file->async_file->ref, ib_uverbs_release_async_event_file);
file->async_file = 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;
}
struct file *ib_uverbs_alloc_async_event_file(struct ib_uverbs_file *uverbs_file,
struct ib_device *ib_dev)
{
struct ib_uverbs_async_event_file *ev_file;
struct file *filp;
ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
if (!ev_file)
return ERR_PTR(-ENOMEM);
ib_uverbs_init_event_queue(&ev_file->ev_queue);
ev_file->uverbs_file = uverbs_file;
kref_get(&ev_file->uverbs_file->ref);
kref_init(&ev_file->ref);
filp = anon_inode_getfile("[infinibandevent]", &uverbs_async_event_fops,
ev_file, O_RDONLY);
if (IS_ERR(filp))
goto err_put_refs;
mutex_lock(&uverbs_file->device->lists_mutex);
list_add_tail(&ev_file->list,
&uverbs_file->device->uverbs_events_file_list);
mutex_unlock(&uverbs_file->device->lists_mutex);
WARN_ON(uverbs_file->async_file);
uverbs_file->async_file = ev_file;
kref_get(&uverbs_file->async_file->ref);
INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
ib_dev,
ib_uverbs_event_handler);
ib_register_event_handler(&uverbs_file->event_handler);
/* At that point async file stuff was fully set */
return filp;
err_put_refs:
kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
kref_put(&ev_file->ref, ib_uverbs_release_async_event_file);
return filp;
}
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 */
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);
out_unlock:
srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
return (ret) ? : count;
}
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;
}
ret = ucontext->device->ops.mmap(ucontext, vma);
out:
srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
return ret;
}
/*
* Each time we map IO memory into user space this keeps track of the mapping.
* When the device is hot-unplugged we 'zap' the mmaps in user space to point
* to the zero page and allow the hot unplug to proceed.
*
* This is necessary for cases like PCI physical hot unplug as the actual BAR
* memory may vanish after this and access to it from userspace could MCE.
*
* RDMA drivers supporting disassociation must have their user space designed
* to cope in some way with their IO pages going to the zero page.
*/
struct rdma_umap_priv {
struct vm_area_struct *vma;
struct list_head list;
};
static const struct vm_operations_struct rdma_umap_ops;
static void rdma_umap_priv_init(struct rdma_umap_priv *priv,
struct vm_area_struct *vma)
{
struct ib_uverbs_file *ufile = vma->vm_file->private_data;
priv->vma = vma;
vma->vm_private_data = priv;
vma->vm_ops = &rdma_umap_ops;
mutex_lock(&ufile->umap_lock);
list_add(&priv->list, &ufile->umaps);
mutex_unlock(&ufile->umap_lock);
}
/*
* 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);
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);
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,
};
/*
* Map IO memory into a process. This is to be called by drivers as part of
* their mmap() functions if they wish to send something like PCI-E BAR memory
* to userspace.
*/
int rdma_user_mmap_io(struct ib_ucontext *ucontext, struct vm_area_struct *vma,
unsigned long pfn, unsigned long size, pgprot_t prot)
{
struct ib_uverbs_file *ufile = ucontext->ufile;
struct rdma_umap_priv *priv;
if (!(vma->vm_flags & VM_SHARED))
return -EINVAL;
if (vma->vm_end - vma->vm_start != size)
return -EINVAL;
/* Driver is using this wrong, must be called by ib_uverbs_mmap */
if (WARN_ON(!vma->vm_file ||
vma->vm_file->private_data != ufile))
return -EINVAL;
lockdep_assert_held(&ufile->device->disassociate_srcu);
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
vma->vm_page_prot = prot;
if (io_remap_pfn_range(vma, vma->vm_start, pfn, size, prot)) {
kfree(priv);
return -EAGAIN;
}
rdma_umap_priv_init(priv, vma);
return 0;
}
EXPORT_SYMBOL(rdma_user_mmap_io);
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);
mm = NULL;
continue;
}
break;
}
mutex_unlock(&ufile->umap_lock);
if (!mm)
return;
/*
* The umap_lock is nested under mmap_sem 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.
*/
down_read(&mm->mmap_sem);
if (!mmget_still_valid(mm))
goto skip_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);
}
mutex_unlock(&ufile->umap_lock);
skip_mm:
up_read(&mm->mmap_sem);
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 (!atomic_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 (atomic_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 = ib_uverbs_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 = ib_uverbs_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 = sprintf(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 = sprintf(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 void 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;
uverbs_dev = kzalloc(sizeof(*uverbs_dev), GFP_KERNEL);
if (!uverbs_dev)
return;
ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
if (ret) {
kfree(uverbs_dev);
return;
}
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;
atomic_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);
INIT_LIST_HEAD(&uverbs_dev->uverbs_events_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)
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;
if (ib_uverbs_create_uapi(device, uverbs_dev))
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;
err_uapi:
ida_free(&uverbs_ida, devnum);
err:
if (atomic_dec_and_test(&uverbs_dev->refcount))
ib_uverbs_comp_dev(uverbs_dev);
wait_for_completion(&uverbs_dev->comp);
put_device(&uverbs_dev->dev);
return;
}
static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
struct ib_device *ib_dev)
{
struct ib_uverbs_file *file;
struct ib_uverbs_async_event_file *event_file;
struct ib_event event;
/* Pending running commands to terminate */
uverbs_disassociate_api_pre(uverbs_dev);
event.event = IB_EVENT_DEVICE_FATAL;
event.element.port_num = 0;
event.device = ib_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);
ib_uverbs_event_handler(&file->event_handler, &event);
uverbs_destroy_ufile_hw(file, RDMA_REMOVE_DRIVER_REMOVE);
kref_put(&file->ref, ib_uverbs_release_file);
mutex_lock(&uverbs_dev->lists_mutex);
}
while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
event_file = list_first_entry(&uverbs_dev->
uverbs_events_file_list,
struct ib_uverbs_async_event_file,
list);
spin_lock_irq(&event_file->ev_queue.lock);
event_file->ev_queue.is_closed = 1;
spin_unlock_irq(&event_file->ev_queue.lock);
list_del(&event_file->list);
ib_unregister_event_handler(
&event_file->uverbs_file->event_handler);
event_file->uverbs_file->event_handler.device =
NULL;
wake_up_interruptible(&event_file->ev_queue.poll_wait);
kill_fasync(&event_file->ev_queue.async_queue, SIGIO, POLL_IN);
}
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;
if (!uverbs_dev)
return;
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 (atomic_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);