1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /* Copyright (c) 2020 Mellanox Technologies Ltd */
3 
4 #include <linux/mlx5/driver.h>
5 #include <linux/mlx5/device.h>
6 #include "mlx5_core.h"
7 #include "dev.h"
8 #include "sf/vhca_event.h"
9 #include "sf/sf.h"
10 #include "sf/mlx5_ifc_vhca_event.h"
11 #include "ecpf.h"
12 #define CREATE_TRACE_POINTS
13 #include "diag/dev_tracepoint.h"
14 
15 struct mlx5_sf_dev_table {
16 	struct xarray devices;
17 	unsigned int max_sfs;
18 	phys_addr_t base_address;
19 	u64 sf_bar_length;
20 	struct notifier_block nb;
21 	struct mutex table_lock; /* Serializes sf life cycle and vhca state change handler */
22 	struct workqueue_struct *active_wq;
23 	struct work_struct work;
24 	u8 stop_active_wq:1;
25 	struct mlx5_core_dev *dev;
26 };
27 
28 static bool mlx5_sf_dev_supported(const struct mlx5_core_dev *dev)
29 {
30 	return MLX5_CAP_GEN(dev, sf) && mlx5_vhca_event_supported(dev);
31 }
32 
33 bool mlx5_sf_dev_allocated(const struct mlx5_core_dev *dev)
34 {
35 	struct mlx5_sf_dev_table *table = dev->priv.sf_dev_table;
36 
37 	return table && !xa_empty(&table->devices);
38 }
39 
40 static ssize_t sfnum_show(struct device *dev, struct device_attribute *attr, char *buf)
41 {
42 	struct auxiliary_device *adev = container_of(dev, struct auxiliary_device, dev);
43 	struct mlx5_sf_dev *sf_dev = container_of(adev, struct mlx5_sf_dev, adev);
44 
45 	return sysfs_emit(buf, "%u\n", sf_dev->sfnum);
46 }
47 static DEVICE_ATTR_RO(sfnum);
48 
49 static struct attribute *sf_device_attrs[] = {
50 	&dev_attr_sfnum.attr,
51 	NULL,
52 };
53 
54 static const struct attribute_group sf_attr_group = {
55 	.attrs = sf_device_attrs,
56 };
57 
58 static const struct attribute_group *sf_attr_groups[2] = {
59 	&sf_attr_group,
60 	NULL
61 };
62 
63 static void mlx5_sf_dev_release(struct device *device)
64 {
65 	struct auxiliary_device *adev = container_of(device, struct auxiliary_device, dev);
66 	struct mlx5_sf_dev *sf_dev = container_of(adev, struct mlx5_sf_dev, adev);
67 
68 	mlx5_adev_idx_free(adev->id);
69 	kfree(sf_dev);
70 }
71 
72 static void mlx5_sf_dev_remove(struct mlx5_core_dev *dev, struct mlx5_sf_dev *sf_dev)
73 {
74 	int id;
75 
76 	id = sf_dev->adev.id;
77 	trace_mlx5_sf_dev_del(dev, sf_dev, id);
78 
79 	auxiliary_device_delete(&sf_dev->adev);
80 	auxiliary_device_uninit(&sf_dev->adev);
81 }
82 
83 static void mlx5_sf_dev_add(struct mlx5_core_dev *dev, u16 sf_index, u16 fn_id, u32 sfnum)
84 {
85 	struct mlx5_sf_dev_table *table = dev->priv.sf_dev_table;
86 	struct mlx5_sf_dev *sf_dev;
87 	struct pci_dev *pdev;
88 	int err;
89 	int id;
90 
91 	id = mlx5_adev_idx_alloc();
92 	if (id < 0) {
93 		err = id;
94 		goto add_err;
95 	}
96 
97 	sf_dev = kzalloc(sizeof(*sf_dev), GFP_KERNEL);
98 	if (!sf_dev) {
99 		mlx5_adev_idx_free(id);
100 		err = -ENOMEM;
101 		goto add_err;
102 	}
103 	pdev = dev->pdev;
104 	sf_dev->adev.id = id;
105 	sf_dev->adev.name = MLX5_SF_DEV_ID_NAME;
106 	sf_dev->adev.dev.release = mlx5_sf_dev_release;
107 	sf_dev->adev.dev.parent = &pdev->dev;
108 	sf_dev->adev.dev.groups = sf_attr_groups;
109 	sf_dev->sfnum = sfnum;
110 	sf_dev->parent_mdev = dev;
111 	sf_dev->fn_id = fn_id;
112 
113 	if (!table->max_sfs) {
114 		mlx5_adev_idx_free(id);
115 		kfree(sf_dev);
116 		err = -EOPNOTSUPP;
117 		goto add_err;
118 	}
119 	sf_dev->bar_base_addr = table->base_address + (sf_index * table->sf_bar_length);
120 
121 	trace_mlx5_sf_dev_add(dev, sf_dev, id);
122 
123 	err = auxiliary_device_init(&sf_dev->adev);
124 	if (err) {
125 		mlx5_adev_idx_free(id);
126 		kfree(sf_dev);
127 		goto add_err;
128 	}
129 
130 	err = auxiliary_device_add(&sf_dev->adev);
131 	if (err) {
132 		put_device(&sf_dev->adev.dev);
133 		goto add_err;
134 	}
135 
136 	err = xa_insert(&table->devices, sf_index, sf_dev, GFP_KERNEL);
137 	if (err)
138 		goto xa_err;
139 	return;
140 
141 xa_err:
142 	mlx5_sf_dev_remove(dev, sf_dev);
143 add_err:
144 	mlx5_core_err(dev, "SF DEV: fail device add for index=%d sfnum=%d err=%d\n",
145 		      sf_index, sfnum, err);
146 }
147 
148 static void mlx5_sf_dev_del(struct mlx5_core_dev *dev, struct mlx5_sf_dev *sf_dev, u16 sf_index)
149 {
150 	struct mlx5_sf_dev_table *table = dev->priv.sf_dev_table;
151 
152 	xa_erase(&table->devices, sf_index);
153 	mlx5_sf_dev_remove(dev, sf_dev);
154 }
155 
156 static int
157 mlx5_sf_dev_state_change_handler(struct notifier_block *nb, unsigned long event_code, void *data)
158 {
159 	struct mlx5_sf_dev_table *table = container_of(nb, struct mlx5_sf_dev_table, nb);
160 	const struct mlx5_vhca_state_event *event = data;
161 	struct mlx5_sf_dev *sf_dev;
162 	u16 max_functions;
163 	u16 sf_index;
164 	u16 base_id;
165 
166 	max_functions = mlx5_sf_max_functions(table->dev);
167 	if (!max_functions)
168 		return 0;
169 
170 	base_id = MLX5_CAP_GEN(table->dev, sf_base_id);
171 	if (event->function_id < base_id || event->function_id >= (base_id + max_functions))
172 		return 0;
173 
174 	sf_index = event->function_id - base_id;
175 	mutex_lock(&table->table_lock);
176 	sf_dev = xa_load(&table->devices, sf_index);
177 	switch (event->new_vhca_state) {
178 	case MLX5_VHCA_STATE_INVALID:
179 	case MLX5_VHCA_STATE_ALLOCATED:
180 		if (sf_dev)
181 			mlx5_sf_dev_del(table->dev, sf_dev, sf_index);
182 		break;
183 	case MLX5_VHCA_STATE_TEARDOWN_REQUEST:
184 		if (sf_dev)
185 			mlx5_sf_dev_del(table->dev, sf_dev, sf_index);
186 		else
187 			mlx5_core_err(table->dev,
188 				      "SF DEV: teardown state for invalid dev index=%d fn_id=0x%x\n",
189 				      sf_index, event->sw_function_id);
190 		break;
191 	case MLX5_VHCA_STATE_ACTIVE:
192 		if (!sf_dev)
193 			mlx5_sf_dev_add(table->dev, sf_index, event->function_id,
194 					event->sw_function_id);
195 		break;
196 	default:
197 		break;
198 	}
199 	mutex_unlock(&table->table_lock);
200 	return 0;
201 }
202 
203 static int mlx5_sf_dev_vhca_arm_all(struct mlx5_sf_dev_table *table)
204 {
205 	struct mlx5_core_dev *dev = table->dev;
206 	u16 max_functions;
207 	u16 function_id;
208 	int err = 0;
209 	int i;
210 
211 	max_functions = mlx5_sf_max_functions(dev);
212 	function_id = MLX5_CAP_GEN(dev, sf_base_id);
213 	/* Arm the vhca context as the vhca event notifier */
214 	for (i = 0; i < max_functions; i++) {
215 		err = mlx5_vhca_event_arm(dev, function_id);
216 		if (err)
217 			return err;
218 
219 		function_id++;
220 	}
221 	return 0;
222 }
223 
224 static void mlx5_sf_dev_add_active_work(struct work_struct *work)
225 {
226 	struct mlx5_sf_dev_table *table = container_of(work, struct mlx5_sf_dev_table, work);
227 	u32 out[MLX5_ST_SZ_DW(query_vhca_state_out)] = {};
228 	struct mlx5_core_dev *dev = table->dev;
229 	u16 max_functions;
230 	u16 function_id;
231 	u16 sw_func_id;
232 	int err = 0;
233 	u8 state;
234 	int i;
235 
236 	max_functions = mlx5_sf_max_functions(dev);
237 	function_id = MLX5_CAP_GEN(dev, sf_base_id);
238 	for (i = 0; i < max_functions; i++, function_id++) {
239 		if (table->stop_active_wq)
240 			return;
241 		err = mlx5_cmd_query_vhca_state(dev, function_id, out, sizeof(out));
242 		if (err)
243 			/* A failure of specific vhca doesn't mean others will
244 			 * fail as well.
245 			 */
246 			continue;
247 		state = MLX5_GET(query_vhca_state_out, out, vhca_state_context.vhca_state);
248 		if (state != MLX5_VHCA_STATE_ACTIVE)
249 			continue;
250 
251 		sw_func_id = MLX5_GET(query_vhca_state_out, out, vhca_state_context.sw_function_id);
252 		mutex_lock(&table->table_lock);
253 		/* Don't probe device which is already probe */
254 		if (!xa_load(&table->devices, i))
255 			mlx5_sf_dev_add(dev, i, function_id, sw_func_id);
256 		/* There is a race where SF got inactive after the query
257 		 * above. e.g.: the query returns that the state of the
258 		 * SF is active, and after that the eswitch manager set it to
259 		 * inactive.
260 		 * This case cannot be managed in SW, since the probing of the
261 		 * SF is on one system, and the inactivation is on a different
262 		 * system.
263 		 * If the inactive is done after the SF perform init_hca(),
264 		 * the SF will fully probe and then removed. If it was
265 		 * done before init_hca(), the SF probe will fail.
266 		 */
267 		mutex_unlock(&table->table_lock);
268 	}
269 }
270 
271 /* In case SFs are generated externally, probe active SFs */
272 static int mlx5_sf_dev_queue_active_work(struct mlx5_sf_dev_table *table)
273 {
274 	if (MLX5_CAP_GEN(table->dev, eswitch_manager))
275 		return 0; /* the table is local */
276 
277 	/* Use a workqueue to probe active SFs, which are in large
278 	 * quantity and may take up to minutes to probe.
279 	 */
280 	table->active_wq = create_singlethread_workqueue("mlx5_active_sf");
281 	if (!table->active_wq)
282 		return -ENOMEM;
283 	INIT_WORK(&table->work, &mlx5_sf_dev_add_active_work);
284 	queue_work(table->active_wq, &table->work);
285 	return 0;
286 }
287 
288 static void mlx5_sf_dev_destroy_active_work(struct mlx5_sf_dev_table *table)
289 {
290 	if (table->active_wq) {
291 		table->stop_active_wq = true;
292 		destroy_workqueue(table->active_wq);
293 	}
294 }
295 
296 void mlx5_sf_dev_table_create(struct mlx5_core_dev *dev)
297 {
298 	struct mlx5_sf_dev_table *table;
299 	unsigned int max_sfs;
300 	int err;
301 
302 	if (!mlx5_sf_dev_supported(dev) || !mlx5_vhca_event_supported(dev))
303 		return;
304 
305 	table = kzalloc(sizeof(*table), GFP_KERNEL);
306 	if (!table) {
307 		err = -ENOMEM;
308 		goto table_err;
309 	}
310 
311 	table->nb.notifier_call = mlx5_sf_dev_state_change_handler;
312 	table->dev = dev;
313 	if (MLX5_CAP_GEN(dev, max_num_sf))
314 		max_sfs = MLX5_CAP_GEN(dev, max_num_sf);
315 	else
316 		max_sfs = 1 << MLX5_CAP_GEN(dev, log_max_sf);
317 	table->sf_bar_length = 1 << (MLX5_CAP_GEN(dev, log_min_sf_size) + 12);
318 	table->base_address = pci_resource_start(dev->pdev, 2);
319 	table->max_sfs = max_sfs;
320 	xa_init(&table->devices);
321 	mutex_init(&table->table_lock);
322 	dev->priv.sf_dev_table = table;
323 
324 	err = mlx5_vhca_event_notifier_register(dev, &table->nb);
325 	if (err)
326 		goto vhca_err;
327 
328 	err = mlx5_sf_dev_queue_active_work(table);
329 	if (err)
330 		goto add_active_err;
331 
332 	err = mlx5_sf_dev_vhca_arm_all(table);
333 	if (err)
334 		goto arm_err;
335 	mlx5_core_dbg(dev, "SF DEV: max sf devices=%d\n", max_sfs);
336 	return;
337 
338 arm_err:
339 	mlx5_sf_dev_destroy_active_work(table);
340 add_active_err:
341 	mlx5_vhca_event_notifier_unregister(dev, &table->nb);
342 vhca_err:
343 	table->max_sfs = 0;
344 	kfree(table);
345 	dev->priv.sf_dev_table = NULL;
346 table_err:
347 	mlx5_core_err(dev, "SF DEV table create err = %d\n", err);
348 }
349 
350 static void mlx5_sf_dev_destroy_all(struct mlx5_sf_dev_table *table)
351 {
352 	struct mlx5_sf_dev *sf_dev;
353 	unsigned long index;
354 
355 	xa_for_each(&table->devices, index, sf_dev) {
356 		xa_erase(&table->devices, index);
357 		mlx5_sf_dev_remove(table->dev, sf_dev);
358 	}
359 }
360 
361 void mlx5_sf_dev_table_destroy(struct mlx5_core_dev *dev)
362 {
363 	struct mlx5_sf_dev_table *table = dev->priv.sf_dev_table;
364 
365 	if (!table)
366 		return;
367 
368 	mlx5_sf_dev_destroy_active_work(table);
369 	mlx5_vhca_event_notifier_unregister(dev, &table->nb);
370 	mutex_destroy(&table->table_lock);
371 
372 	/* Now that event handler is not running, it is safe to destroy
373 	 * the sf device without race.
374 	 */
375 	mlx5_sf_dev_destroy_all(table);
376 
377 	WARN_ON(!xa_empty(&table->devices));
378 	kfree(table);
379 	dev->priv.sf_dev_table = NULL;
380 }
381