Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.15.
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (C) 2017 Netronome Systems, Inc.
  3 * Copyright (C) 2019 Mellanox Technologies. All rights reserved
  4 */
  5
  6#include <linux/device.h>
  7#include <linux/idr.h>
  8#include <linux/kernel.h>
  9#include <linux/list.h>
 10#include <linux/mutex.h>
 11#include <linux/rtnetlink.h>
 12#include <linux/slab.h>
 13#include <linux/sysfs.h>
 14
 15#include "netdevsim.h"
 16
 17static DEFINE_IDA(nsim_bus_dev_ids);
 18static LIST_HEAD(nsim_bus_dev_list);
 19static DEFINE_MUTEX(nsim_bus_dev_list_lock);
 20static bool nsim_bus_enable;
 21
 22static struct nsim_bus_dev *to_nsim_bus_dev(struct device *dev)
 23{
 24	return container_of(dev, struct nsim_bus_dev, dev);
 25}
 26
 27static int nsim_bus_dev_vfs_enable(struct nsim_bus_dev *nsim_bus_dev,
 28				   unsigned int num_vfs)
 29{
 30	nsim_bus_dev->vfconfigs = kcalloc(num_vfs,
 31					  sizeof(struct nsim_vf_config),
 32					  GFP_KERNEL | __GFP_NOWARN);
 33	if (!nsim_bus_dev->vfconfigs)
 34		return -ENOMEM;
 35	nsim_bus_dev->num_vfs = num_vfs;
 36
 37	return 0;
 38}
 39
 40static void nsim_bus_dev_vfs_disable(struct nsim_bus_dev *nsim_bus_dev)
 41{
 42	kfree(nsim_bus_dev->vfconfigs);
 43	nsim_bus_dev->vfconfigs = NULL;
 44	nsim_bus_dev->num_vfs = 0;
 45}
 46
 47static ssize_t
 48nsim_bus_dev_numvfs_store(struct device *dev, struct device_attribute *attr,
 49			  const char *buf, size_t count)
 50{
 51	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
 52	unsigned int num_vfs;
 53	int ret;
 54
 55	ret = kstrtouint(buf, 0, &num_vfs);
 56	if (ret)
 57		return ret;
 58
 59	rtnl_lock();
 60	if (nsim_bus_dev->num_vfs == num_vfs)
 61		goto exit_good;
 62	if (nsim_bus_dev->num_vfs && num_vfs) {
 63		ret = -EBUSY;
 64		goto exit_unlock;
 65	}
 66
 67	if (num_vfs) {
 68		ret = nsim_bus_dev_vfs_enable(nsim_bus_dev, num_vfs);
 69		if (ret)
 70			goto exit_unlock;
 71	} else {
 72		nsim_bus_dev_vfs_disable(nsim_bus_dev);
 73	}
 74exit_good:
 75	ret = count;
 76exit_unlock:
 77	rtnl_unlock();
 78
 79	return ret;
 80}
 81
 82static ssize_t
 83nsim_bus_dev_numvfs_show(struct device *dev,
 84			 struct device_attribute *attr, char *buf)
 85{
 86	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
 87
 88	return sprintf(buf, "%u\n", nsim_bus_dev->num_vfs);
 89}
 90
 91static struct device_attribute nsim_bus_dev_numvfs_attr =
 92	__ATTR(sriov_numvfs, 0664, nsim_bus_dev_numvfs_show,
 93	       nsim_bus_dev_numvfs_store);
 94
 95static ssize_t
 96new_port_store(struct device *dev, struct device_attribute *attr,
 97	       const char *buf, size_t count)
 98{
 99	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
100	struct nsim_dev *nsim_dev = dev_get_drvdata(dev);
101	struct devlink *devlink;
102	unsigned int port_index;
103	int ret;
104
105	/* Prevent to use nsim_bus_dev before initialization. */
106	if (!smp_load_acquire(&nsim_bus_dev->init))
107		return -EBUSY;
108	ret = kstrtouint(buf, 0, &port_index);
109	if (ret)
110		return ret;
111
112	devlink = priv_to_devlink(nsim_dev);
113
114	mutex_lock(&nsim_bus_dev->nsim_bus_reload_lock);
115	devlink_reload_disable(devlink);
116	ret = nsim_dev_port_add(nsim_bus_dev, port_index);
117	devlink_reload_enable(devlink);
118	mutex_unlock(&nsim_bus_dev->nsim_bus_reload_lock);
119	return ret ? ret : count;
120}
121
122static struct device_attribute nsim_bus_dev_new_port_attr = __ATTR_WO(new_port);
123
124static ssize_t
125del_port_store(struct device *dev, struct device_attribute *attr,
126	       const char *buf, size_t count)
127{
128	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
129	struct nsim_dev *nsim_dev = dev_get_drvdata(dev);
130	struct devlink *devlink;
131	unsigned int port_index;
132	int ret;
133
134	/* Prevent to use nsim_bus_dev before initialization. */
135	if (!smp_load_acquire(&nsim_bus_dev->init))
136		return -EBUSY;
137	ret = kstrtouint(buf, 0, &port_index);
138	if (ret)
139		return ret;
140
141	devlink = priv_to_devlink(nsim_dev);
142
143	mutex_lock(&nsim_bus_dev->nsim_bus_reload_lock);
144	devlink_reload_disable(devlink);
145	ret = nsim_dev_port_del(nsim_bus_dev, port_index);
146	devlink_reload_enable(devlink);
147	mutex_unlock(&nsim_bus_dev->nsim_bus_reload_lock);
148	return ret ? ret : count;
149}
150
151static struct device_attribute nsim_bus_dev_del_port_attr = __ATTR_WO(del_port);
152
153static struct attribute *nsim_bus_dev_attrs[] = {
154	&nsim_bus_dev_numvfs_attr.attr,
155	&nsim_bus_dev_new_port_attr.attr,
156	&nsim_bus_dev_del_port_attr.attr,
157	NULL,
158};
159
160static const struct attribute_group nsim_bus_dev_attr_group = {
161	.attrs = nsim_bus_dev_attrs,
162};
163
164static const struct attribute_group *nsim_bus_dev_attr_groups[] = {
165	&nsim_bus_dev_attr_group,
166	NULL,
167};
168
169static void nsim_bus_dev_release(struct device *dev)
170{
171	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
172
173	nsim_bus_dev_vfs_disable(nsim_bus_dev);
174}
175
176static struct device_type nsim_bus_dev_type = {
177	.groups = nsim_bus_dev_attr_groups,
178	.release = nsim_bus_dev_release,
179};
180
181static struct nsim_bus_dev *
182nsim_bus_dev_new(unsigned int id, unsigned int port_count);
183
184static ssize_t
185new_device_store(struct bus_type *bus, const char *buf, size_t count)
186{
187	struct nsim_bus_dev *nsim_bus_dev;
188	unsigned int port_count;
189	unsigned int id;
190	int err;
191
192	err = sscanf(buf, "%u %u", &id, &port_count);
193	switch (err) {
194	case 1:
195		port_count = 1;
196		fallthrough;
197	case 2:
198		if (id > INT_MAX) {
199			pr_err("Value of \"id\" is too big.\n");
200			return -EINVAL;
201		}
202		break;
203	default:
204		pr_err("Format for adding new device is \"id port_count\" (uint uint).\n");
205		return -EINVAL;
206	}
207
208	mutex_lock(&nsim_bus_dev_list_lock);
209	/* Prevent to use resource before initialization. */
210	if (!smp_load_acquire(&nsim_bus_enable)) {
211		err = -EBUSY;
212		goto err;
213	}
214
215	nsim_bus_dev = nsim_bus_dev_new(id, port_count);
216	if (IS_ERR(nsim_bus_dev)) {
217		err = PTR_ERR(nsim_bus_dev);
218		goto err;
219	}
220
221	/* Allow using nsim_bus_dev */
222	smp_store_release(&nsim_bus_dev->init, true);
223
224	list_add_tail(&nsim_bus_dev->list, &nsim_bus_dev_list);
225	mutex_unlock(&nsim_bus_dev_list_lock);
226
227	return count;
228err:
229	mutex_unlock(&nsim_bus_dev_list_lock);
230	return err;
231}
232static BUS_ATTR_WO(new_device);
233
234static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev);
235
236static ssize_t
237del_device_store(struct bus_type *bus, const char *buf, size_t count)
238{
239	struct nsim_bus_dev *nsim_bus_dev, *tmp;
240	unsigned int id;
241	int err;
242
243	err = sscanf(buf, "%u", &id);
244	switch (err) {
245	case 1:
246		if (id > INT_MAX) {
247			pr_err("Value of \"id\" is too big.\n");
248			return -EINVAL;
249		}
250		break;
251	default:
252		pr_err("Format for deleting device is \"id\" (uint).\n");
253		return -EINVAL;
254	}
255
256	err = -ENOENT;
257	mutex_lock(&nsim_bus_dev_list_lock);
258	/* Prevent to use resource before initialization. */
259	if (!smp_load_acquire(&nsim_bus_enable)) {
260		mutex_unlock(&nsim_bus_dev_list_lock);
261		return -EBUSY;
262	}
263	list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) {
264		if (nsim_bus_dev->dev.id != id)
265			continue;
266		list_del(&nsim_bus_dev->list);
267		nsim_bus_dev_del(nsim_bus_dev);
268		err = 0;
269		break;
270	}
271	mutex_unlock(&nsim_bus_dev_list_lock);
272	return !err ? count : err;
273}
274static BUS_ATTR_WO(del_device);
275
276static struct attribute *nsim_bus_attrs[] = {
277	&bus_attr_new_device.attr,
278	&bus_attr_del_device.attr,
279	NULL
280};
281ATTRIBUTE_GROUPS(nsim_bus);
282
283static int nsim_bus_probe(struct device *dev)
284{
285	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
286
287	return nsim_dev_probe(nsim_bus_dev);
288}
289
290static int nsim_bus_remove(struct device *dev)
291{
292	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
293
294	nsim_dev_remove(nsim_bus_dev);
295	return 0;
296}
297
298static int nsim_num_vf(struct device *dev)
299{
300	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
301
302	return nsim_bus_dev->num_vfs;
303}
304
305static struct bus_type nsim_bus = {
306	.name		= DRV_NAME,
307	.dev_name	= DRV_NAME,
308	.bus_groups	= nsim_bus_groups,
309	.probe		= nsim_bus_probe,
310	.remove		= nsim_bus_remove,
311	.num_vf		= nsim_num_vf,
312};
313
314static struct nsim_bus_dev *
315nsim_bus_dev_new(unsigned int id, unsigned int port_count)
316{
317	struct nsim_bus_dev *nsim_bus_dev;
318	int err;
319
320	nsim_bus_dev = kzalloc(sizeof(*nsim_bus_dev), GFP_KERNEL);
321	if (!nsim_bus_dev)
322		return ERR_PTR(-ENOMEM);
323
324	err = ida_alloc_range(&nsim_bus_dev_ids, id, id, GFP_KERNEL);
325	if (err < 0)
326		goto err_nsim_bus_dev_free;
327	nsim_bus_dev->dev.id = err;
328	nsim_bus_dev->dev.bus = &nsim_bus;
329	nsim_bus_dev->dev.type = &nsim_bus_dev_type;
330	nsim_bus_dev->port_count = port_count;
331	nsim_bus_dev->initial_net = current->nsproxy->net_ns;
332	mutex_init(&nsim_bus_dev->nsim_bus_reload_lock);
333	/* Disallow using nsim_bus_dev */
334	smp_store_release(&nsim_bus_dev->init, false);
335
336	err = device_register(&nsim_bus_dev->dev);
337	if (err)
338		goto err_nsim_bus_dev_id_free;
339	return nsim_bus_dev;
340
341err_nsim_bus_dev_id_free:
342	ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id);
343err_nsim_bus_dev_free:
344	kfree(nsim_bus_dev);
345	return ERR_PTR(err);
346}
347
348static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev)
349{
350	/* Disallow using nsim_bus_dev */
351	smp_store_release(&nsim_bus_dev->init, false);
352	device_unregister(&nsim_bus_dev->dev);
353	ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id);
354	kfree(nsim_bus_dev);
355}
356
357static struct device_driver nsim_driver = {
358	.name		= DRV_NAME,
359	.bus		= &nsim_bus,
360	.owner		= THIS_MODULE,
361};
362
363int nsim_bus_init(void)
364{
365	int err;
366
367	err = bus_register(&nsim_bus);
368	if (err)
369		return err;
370	err = driver_register(&nsim_driver);
371	if (err)
372		goto err_bus_unregister;
373	/* Allow using resources */
374	smp_store_release(&nsim_bus_enable, true);
375	return 0;
376
377err_bus_unregister:
378	bus_unregister(&nsim_bus);
379	return err;
380}
381
382void nsim_bus_exit(void)
383{
384	struct nsim_bus_dev *nsim_bus_dev, *tmp;
385
386	/* Disallow using resources */
387	smp_store_release(&nsim_bus_enable, false);
388
389	mutex_lock(&nsim_bus_dev_list_lock);
390	list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) {
391		list_del(&nsim_bus_dev->list);
392		nsim_bus_dev_del(nsim_bus_dev);
393	}
394	mutex_unlock(&nsim_bus_dev_list_lock);
395
396	driver_unregister(&nsim_driver);
397	bus_unregister(&nsim_bus);
398}