1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
new file mode 100644
index 000000000000..7b348bf9df21
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
@@ -0,0 +1,227 @@
+/*
+ * Copyright 2020 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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/poll.h>
+#include <linux/wait.h>
+#include <linux/anon_inodes.h>
+#include <uapi/linux/kfd_ioctl.h>
+#include "amdgpu_vm.h"
+#include "kfd_priv.h"
+#include "kfd_smi_events.h"
+
+struct kfd_smi_client {
+	struct list_head list;
+	struct kfifo fifo;
+	wait_queue_head_t wait_queue;
+	/* events enabled */
+	uint64_t events;
+	struct kfd_dev *dev;
+	spinlock_t lock;
+};
+
+#define MAX_KFIFO_SIZE	1024
+
+static __poll_t kfd_smi_ev_poll(struct file *, struct poll_table_struct *);
+static ssize_t kfd_smi_ev_read(struct file *, char __user *, size_t, loff_t *);
+static ssize_t kfd_smi_ev_write(struct file *, const char __user *, size_t,
+				loff_t *);
+static int kfd_smi_ev_release(struct inode *, struct file *);
+
+static const char kfd_smi_name[] = "kfd_smi_ev";
+
+static const struct file_operations kfd_smi_ev_fops = {
+	.owner = THIS_MODULE,
+	.poll = kfd_smi_ev_poll,
+	.read = kfd_smi_ev_read,
+	.write = kfd_smi_ev_write,
+	.release = kfd_smi_ev_release
+};
+
+static __poll_t kfd_smi_ev_poll(struct file *filep,
+				struct poll_table_struct *wait)
+{
+	struct kfd_smi_client *client = filep->private_data;
+	__poll_t mask = 0;
+
+	poll_wait(filep, &client->wait_queue, wait);
+
+	spin_lock(&client->lock);
+	if (!kfifo_is_empty(&client->fifo))
+		mask = EPOLLIN | EPOLLRDNORM;
+	spin_unlock(&client->lock);
+
+	return mask;
+}
+
+static ssize_t kfd_smi_ev_read(struct file *filep, char __user *user,
+			       size_t size, loff_t *offset)
+{
+	int ret;
+	size_t to_copy;
+	struct kfd_smi_client *client = filep->private_data;
+	unsigned char *buf;
+
+	buf = kmalloc(MAX_KFIFO_SIZE * sizeof(*buf), GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	/* kfifo_to_user can sleep so we can't use spinlock protection around
+	 * it. Instead, we kfifo out as spinlocked then copy them to the user.
+	 */
+	spin_lock(&client->lock);
+	to_copy = kfifo_len(&client->fifo);
+	if (!to_copy) {
+		spin_unlock(&client->lock);
+		ret = -EAGAIN;
+		goto ret_err;
+	}
+	to_copy = min3(size, sizeof(buf), to_copy);
+	ret = kfifo_out(&client->fifo, buf, to_copy);
+	spin_unlock(&client->lock);
+	if (ret <= 0) {
+		ret = -EAGAIN;
+		goto ret_err;
+	}
+
+	ret = copy_to_user(user, buf, to_copy);
+	if (ret) {
+		ret = -EFAULT;
+		goto ret_err;
+	}
+
+	kfree(buf);
+	return to_copy;
+
+ret_err:
+	kfree(buf);
+	return ret;
+}
+
+static ssize_t kfd_smi_ev_write(struct file *filep, const char __user *user,
+				size_t size, loff_t *offset)
+{
+	struct kfd_smi_client *client = filep->private_data;
+	uint64_t events;
+
+	if (!access_ok(user, size) || size < sizeof(events))
+		return -EFAULT;
+	if (copy_from_user(&events, user, sizeof(events)))
+		return -EFAULT;
+
+	WRITE_ONCE(client->events, events);
+
+	return sizeof(events);
+}
+
+static int kfd_smi_ev_release(struct inode *inode, struct file *filep)
+{
+	struct kfd_smi_client *client = filep->private_data;
+	struct kfd_dev *dev = client->dev;
+
+	spin_lock(&dev->smi_lock);
+	list_del_rcu(&client->list);
+	spin_unlock(&dev->smi_lock);
+
+	synchronize_rcu();
+	kfifo_free(&client->fifo);
+	kfree(client);
+
+	return 0;
+}
+
+void kfd_smi_event_update_vmfault(struct kfd_dev *dev, uint16_t pasid)
+{
+	struct amdgpu_device *adev = (struct amdgpu_device *)dev->kgd;
+	struct amdgpu_task_info task_info;
+	/* VmFault msg = (hex)uint32_pid(8) + :(1) + task name(16) = 25 */
+	/* 16 bytes event + 1 byte space + 25 bytes msg + 1 byte \n = 43
+	 */
+	char fifo_in[43];
+	struct kfd_smi_client *client;
+	int len;
+
+	if (list_empty(&dev->smi_clients))
+		return;
+
+	memset(&task_info, 0, sizeof(struct amdgpu_task_info));
+	amdgpu_vm_get_task_info(adev, pasid, &task_info);
+	/* Report VM faults from user applications, not retry from kernel */
+	if (!task_info.pid)
+		return;
+
+	len = snprintf(fifo_in, 43, "%x %x:%s\n", KFD_SMI_EVENT_VMFAULT,
+		task_info.pid, task_info.task_name);
+
+	rcu_read_lock();
+
+	list_for_each_entry_rcu(client, &dev->smi_clients, list) {
+		if (!(READ_ONCE(client->events) & KFD_SMI_EVENT_VMFAULT))
+			continue;
+		spin_lock(&client->lock);
+		if (kfifo_avail(&client->fifo) >= len) {
+			kfifo_in(&client->fifo, fifo_in, len);
+			wake_up_all(&client->wait_queue);
+		}
+		else
+			pr_debug("smi_event(vmfault): no space left\n");
+		spin_unlock(&client->lock);
+	}
+
+	rcu_read_unlock();
+}
+
+int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
+{
+	struct kfd_smi_client *client;
+	int ret;
+
+	client = kzalloc(sizeof(struct kfd_smi_client), GFP_KERNEL);
+	if (!client)
+		return -ENOMEM;
+	INIT_LIST_HEAD(&client->list);
+
+	ret = kfifo_alloc(&client->fifo, MAX_KFIFO_SIZE, GFP_KERNEL);
+	if (ret) {
+		kfree(client);
+		return ret;
+	}
+
+	ret = anon_inode_getfd(kfd_smi_name, &kfd_smi_ev_fops, (void *)client,
+			       O_RDWR);
+	if (ret < 0) {
+		kfifo_free(&client->fifo);
+		kfree(client);
+		return ret;
+	}
+	*fd = ret;
+
+	init_waitqueue_head(&client->wait_queue);
+	spin_lock_init(&client->lock);
+	client->events = 0;
+	client->dev = dev;
+
+	spin_lock(&dev->smi_lock);
+	list_add_rcu(&client->list, &dev->smi_clients);
+	spin_unlock(&dev->smi_lock);
+
+	return 0;
+}