Message-Id: <20210513085725.45528-7-guy.zadicario@intel.com>
Date:   Thu, 13 May 2021 11:57:16 +0300
From:   Guy Zadicario <guy.zadicario@...el.com>
To:     gregkh@...uxfoundation.org, linux-kernel@...r.kernel.org
Cc:     olof@...om.net, alexander.shishkin@...ux.intel.com,
        andriy.shevchenko@...el.com, yochai.shefi-simchon@...el.com,
        guy.zadicario@...el.com
Subject: [PATCH v2 06/15] misc: nnpi: Allow usermode to manage host resources

Provide an IOCTL interface for creating and destroying host memory
resources through a character device (/dev/nnpi_host).

There is a single instance of this character device in the system
regardless of the number of NNP-I devices attached because it
controls host resources which may be shared between different devices.

A nnp_user object, created when an application opens this character
device, identifies the user (client) of the driver and holds a list of
all host resources allocated by that user through the opened file
descriptor.

Host memory resources created through this character device can be mapped
to device access through IOCTLs made to a different, per-device, chardev
(will be introduced on next commits).

All resources will be destroyed when the application closes the connection
or exits.

The IOCTL interface is defined in: include/uapi/misc/intel_nnpi.h

Signed-off-by: Guy Zadicario <guy.zadicario@...el.com>
Reviewed-by: Alexander Shishkin <alexander.shishkin@...ux.intel.com>
---
 MAINTAINERS                            |   1 +
 drivers/misc/intel-nnpi/Makefile       |   2 +-
 drivers/misc/intel-nnpi/device.c       |  14 ++
 drivers/misc/intel-nnpi/host_chardev.c | 346 +++++++++++++++++++++++++++++++++
 drivers/misc/intel-nnpi/host_chardev.h |  12 ++
 drivers/misc/intel-nnpi/nnp_user.c     | 131 +++++++++++++
 drivers/misc/intel-nnpi/nnp_user.h     |  79 ++++++++
 include/uapi/misc/intel_nnpi.h         | 150 ++++++++++++++
 8 files changed, 734 insertions(+), 1 deletion(-)
 create mode 100644 drivers/misc/intel-nnpi/host_chardev.c
 create mode 100644 drivers/misc/intel-nnpi/host_chardev.h
 create mode 100644 drivers/misc/intel-nnpi/nnp_user.c
 create mode 100644 drivers/misc/intel-nnpi/nnp_user.h
 create mode 100644 include/uapi/misc/intel_nnpi.h

diff --git a/MAINTAINERS b/MAINTAINERS
index ff0c3d7..42f3e54 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9320,6 +9320,7 @@ INTEL NNP-I PCI DRIVER
 M:	Guy Zadicario <guy.zadicario@...el.com>
 S:	Supported
 F:	drivers/misc/intel-nnpi/
+F:	include/uapi/misc/intel_nnpi.h
 
 INTEL P-Unit IPC DRIVER
 M:	Zha Qipeng <qipeng.zha@...el.com>
diff --git a/drivers/misc/intel-nnpi/Makefile b/drivers/misc/intel-nnpi/Makefile
index 3713d51..da2863b 100644
--- a/drivers/misc/intel-nnpi/Makefile
+++ b/drivers/misc/intel-nnpi/Makefile
@@ -5,7 +5,7 @@
 
 obj-$(CONFIG_INTEL_NNPI) := intel_nnpi.o intel_nnpi_pcie.o
 
-intel_nnpi-y := device.o msg_scheduler.o hostres.o
+intel_nnpi-y := device.o msg_scheduler.o hostres.o host_chardev.o nnp_user.o
 
 intel_nnpi_pcie-y := nnp_pcie.o
 
diff --git a/drivers/misc/intel-nnpi/device.c b/drivers/misc/intel-nnpi/device.c
index 60c5a94..0f98398 100644
--- a/drivers/misc/intel-nnpi/device.c
+++ b/drivers/misc/intel-nnpi/device.c
@@ -8,6 +8,7 @@
 #include <linux/module.h>
 
 #include "device.h"
+#include "host_chardev.h"
 #include "msg_scheduler.h"
 
 static DEFINE_IDA(dev_ida);
@@ -99,6 +100,19 @@ void nnpdev_destroy(struct nnp_device *nnpdev)
 }
 EXPORT_SYMBOL(nnpdev_destroy);
 
+static int __init nnp_init(void)
+{
+	return nnp_init_host_interface();
+}
+subsys_initcall(nnp_init);
+
+static void __exit nnp_cleanup(void)
+{
+	nnp_release_host_interface();
+	/* dev_ida is already empty here - no point calling ida_destroy */
+}
+module_exit(nnp_cleanup);
+
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Intel(R) NNPI Framework");
 MODULE_AUTHOR("Intel Corporation");
diff --git a/drivers/misc/intel-nnpi/host_chardev.c b/drivers/misc/intel-nnpi/host_chardev.c
new file mode 100644
index 0000000..6048fda
--- /dev/null
+++ b/drivers/misc/intel-nnpi/host_chardev.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2019-2021 Intel Corporation */
+
+#define pr_fmt(fmt)   KBUILD_MODNAME ": " fmt
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/hashtable.h>
+#include <linux/idr.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <uapi/misc/intel_nnpi.h>
+
+#include "device.h"
+#include "host_chardev.h"
+#include "ipc_protocol.h"
+#include "nnp_user.h"
+
+static struct cdev cdev;
+static dev_t       devnum;
+static struct class *class;
+static struct device *dev;
+
+static inline int is_host_file(struct file *f);
+
+static enum dma_data_direction to_dma_dir(unsigned int nnp_dir)
+{
+	/* Ignore IOCTL_INF_RES_NETWORK */
+	switch (nnp_dir & (IOCTL_INF_RES_INPUT | IOCTL_INF_RES_OUTPUT)) {
+	case (IOCTL_INF_RES_INPUT | IOCTL_INF_RES_OUTPUT):
+		return DMA_BIDIRECTIONAL;
+	case IOCTL_INF_RES_INPUT:
+		return DMA_TO_DEVICE;
+	case IOCTL_INF_RES_OUTPUT:
+		return DMA_FROM_DEVICE;
+	default:
+		break;
+	}
+
+	return DMA_NONE;
+}
+
+static long create_hostres(struct nnp_user_info *user_info, void __user *arg,
+			   unsigned int size)
+{
+	int ret;
+	struct nnpdrv_ioctl_create_hostres req;
+	struct host_resource *hostres;
+	struct user_hostres *user_hostres_entry;
+	void __user *uptr;
+	unsigned int io_size = sizeof(req);
+
+	if (size != io_size)
+		return -EINVAL;
+
+	if (copy_from_user(&req, arg, io_size))
+		return -EFAULT;
+
+	if (req.usage_flags & ~IOCTL_RES_USAGE_VALID_MASK)
+		return -EINVAL;
+
+	uptr = u64_to_user_ptr(req.user_ptr);
+	hostres = nnp_hostres_from_usermem(uptr, req.size,
+					   to_dma_dir(req.usage_flags));
+
+	if (IS_ERR(hostres))
+		return PTR_ERR(hostres);
+
+	ret = nnp_user_add_hostres(user_info, hostres, &user_hostres_entry);
+	if (ret < 0) {
+		nnp_hostres_put(hostres);
+		return ret;
+	}
+
+	req.size = nnp_hostres_size(hostres);
+
+	/*
+	 * The created user_hostres_entry holds refcount to the resource,
+	 * no need to keep another one here.
+	 */
+	nnp_hostres_put(hostres);
+
+	req.user_handle = user_hostres_entry->user_handle;
+	if (copy_to_user(arg, &req, io_size)) {
+		ret = -EFAULT;
+		goto destroy_hostres_entry;
+	}
+
+	return 0;
+
+destroy_hostres_entry:
+	nnp_user_remove_hostres(user_hostres_entry);
+
+	return ret;
+}
+
+static long destroy_hostres(struct nnp_user_info *user_info, void __user *arg,
+			    unsigned int size)
+{
+	struct nnpdrv_ioctl_destroy_hostres destroy_args;
+	struct user_hostres *user_hostres_entry;
+	unsigned int io_size = sizeof(destroy_args);
+	int ret = 0;
+
+	if (size != io_size)
+		return -EINVAL;
+
+	if (copy_from_user(&destroy_args, arg, io_size))
+		return -EFAULT;
+
+	/* errno must be cleared on entry */
+	if (destroy_args.o_errno)
+		return -EINVAL;
+
+	mutex_lock(&user_info->mutex);
+	user_hostres_entry = idr_find(&user_info->idr, destroy_args.user_handle);
+	if (user_hostres_entry) {
+		nnp_user_remove_hostres_locked(user_hostres_entry);
+	} else {
+		destroy_args.o_errno = NNPER_NO_SUCH_RESOURCE;
+		if (copy_to_user(arg, &destroy_args, io_size))
+			ret = -EFAULT;
+	}
+
+	mutex_unlock(&user_info->mutex);
+	return ret;
+}
+
+static long lock_hostres(struct nnp_user_info *user_info, void __user *arg,
+			 unsigned int size)
+{
+	int ret = 0;
+	struct nnpdrv_ioctl_lock_hostres lock_args;
+	struct user_hostres *user_hostres_entry;
+	unsigned int io_size = sizeof(lock_args);
+
+	if (size != io_size)
+		return -EINVAL;
+
+	if (copy_from_user(&lock_args, arg, io_size))
+		return -EFAULT;
+
+	/* errno must be cleared on entry */
+	if (lock_args.o_errno)
+		return -EINVAL;
+
+	mutex_lock(&user_info->mutex);
+	user_hostres_entry = idr_find(&user_info->idr, lock_args.user_handle);
+	if (user_hostres_entry) {
+		ret = nnp_hostres_user_lock(user_hostres_entry->hostres);
+	} else {
+		lock_args.o_errno = NNPER_NO_SUCH_RESOURCE;
+		if (copy_to_user(arg, &lock_args, io_size))
+			ret = -EFAULT;
+	}
+
+	mutex_unlock(&user_info->mutex);
+	return ret;
+}
+
+static long unlock_hostres(struct nnp_user_info *user_info, void __user *arg,
+			   unsigned int size)
+{
+	int ret = 0;
+	struct user_hostres *user_hostres_entry;
+	struct nnpdrv_ioctl_lock_hostres lock_args;
+	unsigned int io_size = sizeof(lock_args);
+
+	if (size != io_size)
+		return -EINVAL;
+
+	if (copy_from_user(&lock_args, arg, io_size))
+		return -EFAULT;
+
+	/* errno must be cleared on entry */
+	if (lock_args.o_errno)
+		return -EINVAL;
+
+	mutex_lock(&user_info->mutex);
+	user_hostres_entry = idr_find(&user_info->idr, lock_args.user_handle);
+	if (user_hostres_entry) {
+		ret = nnp_hostres_user_unlock(user_hostres_entry->hostres);
+	} else {
+		lock_args.o_errno = NNPER_NO_SUCH_RESOURCE;
+		if (copy_to_user(arg, &lock_args, sizeof(lock_args)))
+			ret = -EFAULT;
+	}
+
+	mutex_unlock(&user_info->mutex);
+	return ret;
+}
+
+struct file *nnp_host_file_get(int host_fd)
+{
+	struct file *host_file;
+
+	host_file = fget(host_fd);
+	if (is_host_file(host_file))
+		return host_file;
+
+	if (host_file)
+		fput(host_file);
+
+	return NULL;
+}
+
+/*
+ * Inference host cdev (/dev/nnpi_host) file operation functions
+ */
+
+static int host_open(struct inode *inode, struct file *f)
+{
+	struct nnp_user_info *user_info;
+
+	if (!is_host_file(f))
+		return -EINVAL;
+
+	user_info = kzalloc(sizeof(*user_info), GFP_KERNEL);
+	if (!user_info)
+		return -ENOMEM;
+
+	nnp_user_init(user_info);
+
+	f->private_data = user_info;
+
+	return 0;
+}
+
+static int host_release(struct inode *inode, struct file *f)
+{
+	struct nnp_user_info *user_info;
+
+	if (!is_host_file(f))
+		return -EINVAL;
+
+	user_info = f->private_data;
+
+	nnp_user_destroy_all(user_info);
+	f->private_data = NULL;
+
+	return 0;
+}
+
+static long host_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+{
+	long ret = 0;
+	struct nnp_user_info *user_info = f->private_data;
+	unsigned int ioc_nr, size;
+
+	if (!is_host_file(f))
+		return -ENOTTY;
+
+	if (_IOC_TYPE(cmd) != 'h')
+		return -EINVAL;
+
+	ioc_nr = _IOC_NR(cmd);
+	size = _IOC_SIZE(cmd);
+
+	switch (ioc_nr) {
+	case _IOC_NR(IOCTL_INF_CREATE_HOST_RESOURCE):
+		ret = create_hostres(user_info, (void __user *)arg, size);
+		break;
+	case _IOC_NR(IOCTL_INF_DESTROY_HOST_RESOURCE):
+		ret = destroy_hostres(user_info, (void __user *)arg, size);
+		break;
+	case _IOC_NR(IOCTL_INF_UNLOCK_HOST_RESOURCE):
+		ret = unlock_hostres(user_info, (void __user *)arg, size);
+		break;
+	case _IOC_NR(IOCTL_INF_LOCK_HOST_RESOURCE):
+		ret = lock_hostres(user_info, (void __user *)arg, size);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct file_operations host_fops = {
+	.owner = THIS_MODULE,
+	.open = host_open,
+	.release = host_release,
+	.unlocked_ioctl = host_ioctl,
+	.compat_ioctl = host_ioctl,
+};
+
+static inline int is_host_file(struct file *f)
+{
+	return f && f->f_op == &host_fops;
+}
+
+int nnp_init_host_interface(void)
+{
+	int ret;
+
+	ret = alloc_chrdev_region(&devnum, 0, 1, NNPDRV_INF_HOST_DEV_NAME);
+	if (ret < 0)
+		return ret;
+
+	cdev_init(&cdev, &host_fops);
+	cdev.owner = THIS_MODULE;
+
+	ret = cdev_add(&cdev, devnum, 1);
+	if (ret < 0)
+		goto err_region;
+
+	class = class_create(THIS_MODULE, NNPDRV_INF_HOST_DEV_NAME);
+	if (IS_ERR(class)) {
+		ret = PTR_ERR(class);
+		goto err_cdev;
+	}
+
+	dev = device_create(class, NULL, devnum, NULL, NNPDRV_INF_HOST_DEV_NAME);
+	if (IS_ERR(dev)) {
+		ret = PTR_ERR(dev);
+		goto err_class;
+	}
+
+	ret = nnp_hostres_init_sysfs(dev);
+	if (ret < 0)
+		goto err_device;
+
+	return 0;
+
+err_device:
+	device_destroy(class, devnum);
+err_class:
+	class_destroy(class);
+err_cdev:
+	cdev_del(&cdev);
+err_region:
+	unregister_chrdev_region(devnum, 1);
+
+	return ret;
+}
+
+void nnp_release_host_interface(void)
+{
+	nnp_hostres_fini_sysfs(dev);
+	device_destroy(class, devnum);
+	class_destroy(class);
+	cdev_del(&cdev);
+	unregister_chrdev_region(devnum, 1);
+}
diff --git a/drivers/misc/intel-nnpi/host_chardev.h b/drivers/misc/intel-nnpi/host_chardev.h
new file mode 100644
index 0000000..5812e0f
--- /dev/null
+++ b/drivers/misc/intel-nnpi/host_chardev.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2019-2021 Intel Corporation */
+
+#ifndef _NNPDRV_INFERENCE_H
+#define _NNPDRV_INFERENCE_H
+
+int nnp_init_host_interface(void);
+void nnp_release_host_interface(void);
+
+struct file *nnp_host_file_get(int host_fd);
+
+#endif
diff --git a/drivers/misc/intel-nnpi/nnp_user.c b/drivers/misc/intel-nnpi/nnp_user.c
new file mode 100644
index 0000000..51d7418
--- /dev/null
+++ b/drivers/misc/intel-nnpi/nnp_user.c
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2019-2021 Intel Corporation */
+
+#include <linux/slab.h>
+
+#include "nnp_user.h"
+
+void nnp_user_init(struct nnp_user_info *user_info)
+{
+	INIT_LIST_HEAD(&user_info->hostres_list);
+	mutex_init(&user_info->mutex);
+	kref_init(&user_info->ref);
+	idr_init(&user_info->idr);
+}
+
+void nnp_user_get(struct nnp_user_info *user_info)
+{
+	kref_get(&user_info->ref);
+}
+
+static void nnp_user_release(struct kref *kref)
+{
+	struct nnp_user_info *user_info =
+		container_of(kref, struct nnp_user_info, ref);
+	struct completion *completion = user_info->close_completion;
+
+	idr_destroy(&user_info->idr);
+	kfree(user_info);
+	complete(completion);
+}
+
+void nnp_user_put(struct nnp_user_info *user_info)
+{
+	kref_put(&user_info->ref, nnp_user_release);
+}
+
+int nnp_user_add_hostres(struct nnp_user_info *user_info,
+			 struct host_resource *hostres,
+			 struct user_hostres **user_hostres_entry)
+{
+	struct user_hostres *hr_entry;
+	int id;
+
+	hr_entry = kmalloc(sizeof(*hr_entry), GFP_KERNEL);
+	if (!hr_entry)
+		return -ENOMEM;
+
+	/*
+	 * Increment refcount to hostres for the entry reference.
+	 * (caller holds reference to it, so we know it exist).
+	 */
+	nnp_hostres_get(hostres);
+	hr_entry->hostres = hostres;
+
+	/*
+	 * We are called from ioctl of file that own this user_info,
+	 * So it safe to assume it exist.
+	 */
+	nnp_user_get(user_info);
+	hr_entry->user_info = user_info;
+
+	mutex_lock(&user_info->mutex);
+	/*
+	 * We allocate handle starting from 1 and not 0 to allow
+	 * user-space treat zero as invalid handle
+	 */
+	id = idr_alloc(&user_info->idr, hr_entry, 1, -1, GFP_KERNEL);
+	if (id < 0) {
+		nnp_user_put(user_info);
+		nnp_hostres_put(hostres);
+		kfree(hr_entry);
+		mutex_unlock(&user_info->mutex);
+		return -ENOSPC;
+	}
+	hr_entry->user_handle = id;
+	list_add(&hr_entry->node, &user_info->hostres_list);
+	mutex_unlock(&user_info->mutex);
+
+	*user_hostres_entry = hr_entry;
+
+	return 0;
+}
+
+void nnp_user_remove_hostres_locked(struct user_hostres *hr_entry)
+{
+	struct nnp_user_info *user_info = hr_entry->user_info;
+
+	idr_remove(&user_info->idr, hr_entry->user_handle);
+	list_del(&hr_entry->node);
+
+	nnp_hostres_put(hr_entry->hostres);
+
+	kfree(hr_entry);
+	nnp_user_put(user_info);
+}
+
+void nnp_user_remove_hostres(struct user_hostres *hr_entry)
+{
+	struct nnp_user_info *user_info = hr_entry->user_info;
+
+	mutex_lock(&user_info->mutex);
+	nnp_user_remove_hostres_locked(hr_entry);
+	mutex_unlock(&user_info->mutex);
+}
+
+void nnp_user_destroy_all(struct nnp_user_info *user_info)
+{
+	struct user_hostres *user_hostres_entry;
+	DECLARE_COMPLETION_ONSTACK(completion);
+
+	mutex_lock(&user_info->mutex);
+
+	/* destroy all hostreses owned by the "user" */
+	while (!list_empty(&user_info->hostres_list)) {
+		user_hostres_entry = list_first_entry(&user_info->hostres_list,
+						      struct user_hostres, node);
+		/*
+		 * We can safely destroy this object without checking
+		 * its refcount since we get here only after the host char-dev
+		 * as well as all cmd_chan char-devs that may hold temporary
+		 * reference to this object are already released.
+		 */
+		nnp_user_remove_hostres_locked(user_hostres_entry);
+	}
+	mutex_unlock(&user_info->mutex);
+
+	/* wait for all channels and hostreses to be destroyed */
+	user_info->close_completion = &completion;
+	nnp_user_put(user_info);
+	wait_for_completion(&completion);
+}
diff --git a/drivers/misc/intel-nnpi/nnp_user.h b/drivers/misc/intel-nnpi/nnp_user.h
new file mode 100644
index 0000000..429ac13
--- /dev/null
+++ b/drivers/misc/intel-nnpi/nnp_user.h
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2019-2021 Intel Corporation */
+
+#ifndef _NNPDRV_INF_PROC_H
+#define _NNPDRV_INF_PROC_H
+
+#include <linux/kref.h>
+#include <linux/types.h>
+
+#include "hostres.h"
+
+/**
+ * struct nnp_user_info - structure for per-user info
+ * @ref: refcount to this "user" object
+ * @hostres_list: list of host resources
+ * @close_completion: used to wait for all channels of this user to be
+ *                    destroyed before closing the user.
+ * @mutex: protects hostres_list and idr modifications
+ * @idr: used to generate user handles to created host resources
+ * @user_list_node: list node to attach this struct in "list of users".
+ *
+ * structure to hold per-user info,
+ * a "user" is created for each open made to the host char dev (/dev/nnpi_host).
+ * It holds a list of all host resources created through requests from
+ * the same client ("user").
+ * device communication "channels", created by device char dev (/dev/nnpi%d)
+ * must be correlated with a "user" object which is supplied from user-space
+ * by the opened file descriptor to /dev/nnpi_host. Such "channel" may access
+ * only host resources created by the same "user".
+ * The lifetime of this object last at least for the duration of the host char
+ * device file struct but can last longer if some channel objects still hold
+ * a reference to it (this is why @ref is needed).
+ */
+struct nnp_user_info {
+	struct kref         ref;
+	struct list_head    hostres_list;
+	struct completion   *close_completion;
+	struct mutex        mutex;
+	struct idr          idr;
+	struct list_head    user_list_node;
+};
+
+/**
+ * struct user_hostres - structure for host resource created by user
+ * @node: list node to attach this struct to nnp_user_info::hostres_list
+ * @hostres: the actual host resource object
+ * @user_handle: handle allocated from idr object, used as handle to this
+ *               object in ioctl ABI.
+ * @user_info: pointer to "user" which created this resource.
+ *             it is used only during destruction of the object.
+ *
+ * structure for a host resource object which created through host char dev
+ * request. The lifetime of this structure ends when the user request to
+ * destroy it through ioctl call. The underlying @hostres may still continue
+ * to exist if command channel (cmd_chan) objects has mapped the resource to
+ * device access.
+ */
+struct user_hostres {
+	struct list_head             node;
+	struct host_resource         *hostres;
+	int                          user_handle;
+	struct nnp_user_info         *user_info;
+};
+
+void nnp_user_init(struct nnp_user_info *user_info);
+
+void nnp_user_get(struct nnp_user_info *user_info);
+void nnp_user_put(struct nnp_user_info *user_info);
+
+int nnp_user_add_hostres(struct nnp_user_info *user_info,
+			 struct host_resource *hostres,
+			 struct user_hostres **user_hostres_entry);
+
+void nnp_user_remove_hostres(struct user_hostres *hr_entry);
+void nnp_user_remove_hostres_locked(struct user_hostres *hr_entry);
+
+void nnp_user_destroy_all(struct nnp_user_info *user_info);
+
+#endif
diff --git a/include/uapi/misc/intel_nnpi.h b/include/uapi/misc/intel_nnpi.h
new file mode 100644
index 0000000..5114aea
--- /dev/null
+++ b/include/uapi/misc/intel_nnpi.h
@@ -0,0 +1,150 @@
+/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */
+/* Copyright (C) 2019-2021 Intel Corporation */
+
+#ifndef _NNP_UAPI_H
+#define _NNP_UAPI_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+#include <stdbool.h>
+
+#define NNPDRV_INF_HOST_DEV_NAME "nnpi_host"
+
+/*
+ * ioctls for /dev/nnpi_host device
+ */
+
+/*
+ * IOCTL_INF_CREATE_HOST_RESOURCE:
+ *
+ * A request to create a host memory resource object that can then be mapped
+ * and accessed by the NNP-I device's DMA engine.
+ * The created host resource is pinned in memory for its entire lifecycle.
+ * The memory of the resource is backed by user allocated memory which
+ * get pinned by the IOCTL.
+ *
+ * See description of nnpdrv_ioctl_create_hostres structure for more details.
+ *
+ * The ioctl returns a handle to the created host resource.
+ */
+#define IOCTL_INF_CREATE_HOST_RESOURCE      \
+	_IOWR('h', 0, struct nnpdrv_ioctl_create_hostres)
+
+/*
+ * IOCTL_INF_DESTROY_HOST_RESOURCE:
+ *
+ * A request to destoy a host resource object.
+ */
+#define IOCTL_INF_DESTROY_HOST_RESOURCE     \
+	_IOWR('h', 2, struct nnpdrv_ioctl_destroy_hostres)
+
+/*
+ * IOCTL_INF_LOCK_HOST_RESOURCE:
+ *
+ * A request to lock a host resource for cpu access for either
+ * read or write.
+ *
+ * This IOCTL does *not* synchronize accessed to host memory between host
+ * cpu and the device's DMA engine. It is used only for either flush or
+ * invalidate cpu caches to let the device see the last writes made from
+ * host cpu and let cpu read up-to-date content of the resource after the
+ * device changed it.
+ *
+ * This synchronization is not required on all platforms, when mapping
+ * the resource for device access, using IOCTL_NNPI_DEVICE_CHANNEL_MAP_HOSTRES,
+ * the application receive an indication if such synchronization is needed
+ * or not with that device.
+ *
+ * When such synchronization is needed:
+ * When application wants to change host resource content to be read by the
+ * device, it should first lock it for write, change its content by accessing
+ * it's mapped virtual address and then call this ioctl again to unlock it
+ * before sending a command to the device which may read the resource.
+ * When the application received indication that the device has changed the
+ * resource content, it should first lock the resource for reading before
+ * accessing its memory.
+ */
+#define IOCTL_INF_LOCK_HOST_RESOURCE        \
+	_IOWR('h', 3, struct nnpdrv_ioctl_lock_hostres)
+
+/*
+ * IOCTL_INF_UNLOCK_HOST_RESOURCE:
+ *
+ * A request to unlock a host resource that was previously locked for cpu access.
+ */
+#define IOCTL_INF_UNLOCK_HOST_RESOURCE      \
+	_IOWR('h', 4, struct nnpdrv_ioctl_lock_hostres)
+
+/*
+ * The below are possible bit masks that can be specified in
+ * usage_flags field of struct nnpdrv_ioctl_create_hostres.
+ * It specify attribute and usage flags for a host resource.
+ */
+#define IOCTL_INF_RES_INPUT     (1u << 0) /* being read by the NNP-I device */
+#define IOCTL_INF_RES_OUTPUT    (1u << 1) /* being written by the device */
+#define IOCTL_RES_USAGE_VALID_MASK (IOCTL_INF_RES_INPUT | IOCTL_INF_RES_OUTPUT)
+
+/**
+ * struct nnpdrv_ioctl_create_hostres - IOCTL_INF_CREATE_HOST_RESOURCE payload
+ * @user_ptr: User virtual address.
+ * @size: User memory size on input. Host resource size on output.
+ * @usage_flags: resource usage flag bits, IOCTL_INF_RES_*
+ * @user_handle: resource handle on output.
+ *
+ * argument structure for IOCTL_INF_CREATE_HOST_RESOURCE ioctl
+ *
+ * @user_ptr should be initialized to a user virtual address and @size
+ * should be initialized with it's size, the user memory will be pinned and will
+ * hold the host resource content.
+ *
+ * On output, @user_handle is a handle to the created host resource that can be
+ * used later with other IOCTLs and @size is the size of the host resource.
+ */
+struct nnpdrv_ioctl_create_hostres {
+	__u64 user_ptr;
+	__u64 size;
+	__u32 usage_flags;
+	__s32 user_handle;
+};
+
+/**
+ * struct nnpdrv_ioctl_lock_hostres - IOCTL_INF_LOCK_HOST_RESOURCE payload
+ * @user_handle: handle to host resource object
+ * @o_errno: On input, must be set to 0.
+ *           On output, 0 on success, one of the NNPERR_* error codes on error.
+ *
+ * argument structure for IOCTL_INF_LOCK_HOST_RESOURCE and
+ * IOCTL_INF_LOCK_HOST_RESOURCE ioctl calls.
+ */
+struct nnpdrv_ioctl_lock_hostres {
+	__s32 user_handle;
+	__u32 o_errno;
+};
+
+/**
+ * struct nnpdrv_ioctl_destroy_hostres - IOCTL_INF_DESTROY_HOST_RESOURCE payload
+ * @user_handle: handle to host resource object
+ * @o_errno: On input, must be set to 0.
+ *           On output, 0 on success, one of the NNPERR_* error codes on error.
+ *
+ * argument structure for IOCTL_INF_DESTROY_HOST_RESOURCE ioctl
+ */
+struct nnpdrv_ioctl_destroy_hostres {
+	__s32 user_handle;
+	__u32 o_errno;
+};
+
+/****************************************************************
+ * Error code values - errors returned in o_errno fields of
+ * above structures.
+ ****************************************************************/
+#define	NNP_ERRNO_BASE	                        200
+#define	NNPER_DEVICE_NOT_READY			(NNP_ERRNO_BASE + 1)
+#define	NNPER_NO_SUCH_RESOURCE			(NNP_ERRNO_BASE + 2)
+#define	NNPER_INCOMPATIBLE_RESOURCES		(NNP_ERRNO_BASE + 3)
+#define	NNPER_DEVICE_ERROR			(NNP_ERRNO_BASE + 4)
+#define NNPER_NO_SUCH_CHANNEL                   (NNP_ERRNO_BASE + 5)
+#define NNPER_NO_SUCH_HOSTRES_MAP               (NNP_ERRNO_BASE + 6)
+#define NNPER_VERSIONS_MISMATCH                 (NNP_ERRNO_BASE + 7)
+
+#endif /* of _NNP_UAPI_H */
-- 
1.8.3.1

Powered by blists - more mailing lists