1/*
  2 * Copyright 2020 Advanced Micro Devices, Inc.
  3 *
  4 * Permission is hereby granted, free of charge, to any person obtaining a
  5 * copy of this software and associated documentation files (the "Software"),
  6 * to deal in the Software without restriction, including without limitation
  7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  8 * and/or sell copies of the Software, and to permit persons to whom the
  9 * Software is furnished to do so, subject to the following conditions:
 10 *
 11 * The above copyright notice and this permission notice shall be included in
 12 * all copies or substantial portions of the Software.
 13 *
 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 20 * OTHER DEALINGS IN THE SOFTWARE.
 21 */
 22
 23#include <linux/poll.h>
 24#include <linux/wait.h>
 25#include <linux/anon_inodes.h>
 26#include <uapi/linux/kfd_ioctl.h>
 27#include "amdgpu.h"
 28#include "amdgpu_vm.h"
 29#include "kfd_priv.h"
 30#include "kfd_smi_events.h"
 31
 32struct kfd_smi_client {
 33	struct list_head list;
 34	struct kfifo fifo;
 35	wait_queue_head_t wait_queue;
 36	/* events enabled */
 37	uint64_t events;
 38	struct kfd_dev *dev;
 39	spinlock_t lock;
 40};
 41
 42#define MAX_KFIFO_SIZE	1024
 43
 44static __poll_t kfd_smi_ev_poll(struct file *, struct poll_table_struct *);
 45static ssize_t kfd_smi_ev_read(struct file *, char __user *, size_t, loff_t *);
 46static ssize_t kfd_smi_ev_write(struct file *, const char __user *, size_t,
 47				loff_t *);
 48static int kfd_smi_ev_release(struct inode *, struct file *);
 49
 50static const char kfd_smi_name[] = "kfd_smi_ev";
 51
 52static const struct file_operations kfd_smi_ev_fops = {
 53	.owner = THIS_MODULE,
 54	.poll = kfd_smi_ev_poll,
 55	.read = kfd_smi_ev_read,
 56	.write = kfd_smi_ev_write,
 57	.release = kfd_smi_ev_release
 58};
 59
 60static __poll_t kfd_smi_ev_poll(struct file *filep,
 61				struct poll_table_struct *wait)
 62{
 63	struct kfd_smi_client *client = filep->private_data;
 64	__poll_t mask = 0;
 65
 66	poll_wait(filep, &client->wait_queue, wait);
 67
 68	spin_lock(&client->lock);
 69	if (!kfifo_is_empty(&client->fifo))
 70		mask = EPOLLIN | EPOLLRDNORM;
 71	spin_unlock(&client->lock);
 72
 73	return mask;
 74}
 75
 76static ssize_t kfd_smi_ev_read(struct file *filep, char __user *user,
 77			       size_t size, loff_t *offset)
 78{
 79	int ret;
 80	size_t to_copy;
 81	struct kfd_smi_client *client = filep->private_data;
 82	unsigned char *buf;
 83
 84	buf = kmalloc_array(MAX_KFIFO_SIZE, sizeof(*buf), GFP_KERNEL);
 85	if (!buf)
 86		return -ENOMEM;
 87
 88	/* kfifo_to_user can sleep so we can't use spinlock protection around
 89	 * it. Instead, we kfifo out as spinlocked then copy them to the user.
 90	 */
 91	spin_lock(&client->lock);
 92	to_copy = kfifo_len(&client->fifo);
 93	if (!to_copy) {
 94		spin_unlock(&client->lock);
 95		ret = -EAGAIN;
 96		goto ret_err;
 97	}
 98	to_copy = min3(size, sizeof(buf), to_copy);
 99	ret = kfifo_out(&client->fifo, buf, to_copy);
100	spin_unlock(&client->lock);
101	if (ret <= 0) {
102		ret = -EAGAIN;
103		goto ret_err;
104	}
105
106	ret = copy_to_user(user, buf, to_copy);
107	if (ret) {
108		ret = -EFAULT;
109		goto ret_err;
110	}
111
112	kfree(buf);
113	return to_copy;
114
115ret_err:
116	kfree(buf);
117	return ret;
118}
119
120static ssize_t kfd_smi_ev_write(struct file *filep, const char __user *user,
121				size_t size, loff_t *offset)
122{
123	struct kfd_smi_client *client = filep->private_data;
124	uint64_t events;
125
126	if (!access_ok(user, size) || size < sizeof(events))
127		return -EFAULT;
128	if (copy_from_user(&events, user, sizeof(events)))
129		return -EFAULT;
130
131	WRITE_ONCE(client->events, events);
132
133	return sizeof(events);
134}
135
136static int kfd_smi_ev_release(struct inode *inode, struct file *filep)
137{
138	struct kfd_smi_client *client = filep->private_data;
139	struct kfd_dev *dev = client->dev;
140
141	spin_lock(&dev->smi_lock);
142	list_del_rcu(&client->list);
143	spin_unlock(&dev->smi_lock);
144
145	synchronize_rcu();
146	kfifo_free(&client->fifo);
147	kfree(client);
148
149	return 0;
150}
151
152static void add_event_to_kfifo(struct kfd_dev *dev, unsigned int smi_event,
153			      char *event_msg, int len)
154{
155	struct kfd_smi_client *client;
156
157	rcu_read_lock();
158
159	list_for_each_entry_rcu(client, &dev->smi_clients, list) {
160		if (!(READ_ONCE(client->events) &
161				KFD_SMI_EVENT_MASK_FROM_INDEX(smi_event)))
162			continue;
163		spin_lock(&client->lock);
164		if (kfifo_avail(&client->fifo) >= len) {
165			kfifo_in(&client->fifo, event_msg, len);
166			wake_up_all(&client->wait_queue);
167		} else {
168			pr_debug("smi_event(EventID: %u): no space left\n",
169					smi_event);
170		}
171		spin_unlock(&client->lock);
172	}
173
174	rcu_read_unlock();
175}
176
177void kfd_smi_event_update_gpu_reset(struct kfd_dev *dev, bool post_reset)
178{
179	/*
180	 * GpuReset msg = Reset seq number (incremented for
181	 * every reset message sent before GPU reset).
182	 * 1 byte event + 1 byte space + 8 bytes seq num +
183	 * 1 byte \n + 1 byte \0 = 12
184	 */
185	char fifo_in[12];
186	int len;
187	unsigned int event;
188
189	if (list_empty(&dev->smi_clients))
190		return;
191
192	memset(fifo_in, 0x0, sizeof(fifo_in));
193
194	if (post_reset) {
195		event = KFD_SMI_EVENT_GPU_POST_RESET;
196	} else {
197		event = KFD_SMI_EVENT_GPU_PRE_RESET;
198		++(dev->reset_seq_num);
199	}
200
201	len = snprintf(fifo_in, sizeof(fifo_in), "%x %x\n", event,
202						dev->reset_seq_num);
203
204	add_event_to_kfifo(dev, event, fifo_in, len);
205}
206
207void kfd_smi_event_update_thermal_throttling(struct kfd_dev *dev,
208					     uint32_t throttle_bitmask)
209{
210	struct amdgpu_device *adev = (struct amdgpu_device *)dev->kgd;
211	/*
212	 * ThermalThrottle msg = throttle_bitmask(8):
213	 * 			 thermal_interrupt_count(16):
214	 * 1 byte event + 1 byte space + 8 byte throttle_bitmask +
215	 * 1 byte : + 16 byte thermal_interupt_counter + 1 byte \n +
216	 * 1 byte \0 = 29
217	 */
218	char fifo_in[29];
219	int len;
220
221	if (list_empty(&dev->smi_clients))
222		return;
223
224	len = snprintf(fifo_in, sizeof(fifo_in), "%x %x:%llx\n",
225		       KFD_SMI_EVENT_THERMAL_THROTTLE, throttle_bitmask,
226		       atomic64_read(&adev->smu.throttle_int_counter));
227
228	add_event_to_kfifo(dev, KFD_SMI_EVENT_THERMAL_THROTTLE,	fifo_in, len);
229}
230
231void kfd_smi_event_update_vmfault(struct kfd_dev *dev, uint16_t pasid)
232{
233	struct amdgpu_device *adev = (struct amdgpu_device *)dev->kgd;
234	struct amdgpu_task_info task_info;
235	/* VmFault msg = (hex)uint32_pid(8) + :(1) + task name(16) = 25 */
236	/* 1 byte event + 1 byte space + 25 bytes msg + 1 byte \n +
237	 * 1 byte \0 = 29
238	 */
239	char fifo_in[29];
240	int len;
241
242	if (list_empty(&dev->smi_clients))
243		return;
244
245	memset(&task_info, 0, sizeof(struct amdgpu_task_info));
246	amdgpu_vm_get_task_info(adev, pasid, &task_info);
247	/* Report VM faults from user applications, not retry from kernel */
248	if (!task_info.pid)
249		return;
250
251	len = snprintf(fifo_in, sizeof(fifo_in), "%x %x:%s\n", KFD_SMI_EVENT_VMFAULT,
252		task_info.pid, task_info.task_name);
253
254	add_event_to_kfifo(dev, KFD_SMI_EVENT_VMFAULT, fifo_in, len);
255}
256
257int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
258{
259	struct kfd_smi_client *client;
260	int ret;
261
262	client = kzalloc(sizeof(struct kfd_smi_client), GFP_KERNEL);
263	if (!client)
264		return -ENOMEM;
265	INIT_LIST_HEAD(&client->list);
266
267	ret = kfifo_alloc(&client->fifo, MAX_KFIFO_SIZE, GFP_KERNEL);
268	if (ret) {
269		kfree(client);
270		return ret;
271	}
272
273	ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
274			       O_RDWR);
275	if (ret < 0) {
276		kfifo_free(&client->fifo);
277		kfree(client);
278		return ret;
279	}
280	*fd = ret;
281
282	init_waitqueue_head(&client->wait_queue);
283	spin_lock_init(&client->lock);
284	client->events = 0;
285	client->dev = dev;
286
287	spin_lock(&dev->smi_lock);
288	list_add_rcu(&client->list, &dev->smi_clients);
289	spin_unlock(&dev->smi_lock);
290
291	return 0;
292}