xref: /linux/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c (revision 4003c9e78778e93188a09d6043a74f7154449d43)
1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /* Copyright (c) 2019 Mellanox Technologies. */
3 
4 #include <linux/pci.h>
5 #include <linux/interrupt.h>
6 #include <linux/notifier.h>
7 #include <linux/mlx5/driver.h>
8 #include <linux/mlx5/vport.h>
9 #include "mlx5_core.h"
10 #include "mlx5_irq.h"
11 #include "pci_irq.h"
12 #include "lib/sf.h"
13 #include "lib/eq.h"
14 #ifdef CONFIG_RFS_ACCEL
15 #include <linux/cpu_rmap.h>
16 #endif
17 
18 #define MLX5_SFS_PER_CTRL_IRQ 64
19 #define MLX5_MAX_MSIX_PER_SF 256
20 #define MLX5_IRQ_CTRL_SF_MAX 8
21 /* min num of vectors for SFs to be enabled */
22 #define MLX5_IRQ_VEC_COMP_BASE_SF 2
23 #define MLX5_IRQ_VEC_COMP_BASE 1
24 
25 #define MLX5_EQ_SHARE_IRQ_MAX_COMP (8)
26 #define MLX5_EQ_SHARE_IRQ_MAX_CTRL (UINT_MAX)
27 #define MLX5_EQ_SHARE_IRQ_MIN_COMP (1)
28 #define MLX5_EQ_SHARE_IRQ_MIN_CTRL (4)
29 
30 struct mlx5_irq {
31 	struct atomic_notifier_head nh;
32 	cpumask_var_t mask;
33 	char name[MLX5_MAX_IRQ_FORMATTED_NAME];
34 	struct mlx5_irq_pool *pool;
35 	int refcount;
36 	struct msi_map map;
37 	u32 pool_index;
38 };
39 
40 struct mlx5_irq_table {
41 	struct mlx5_irq_pool *pcif_pool;
42 	struct mlx5_irq_pool *sf_ctrl_pool;
43 	struct mlx5_irq_pool *sf_comp_pool;
44 };
45 
mlx5_core_func_to_vport(const struct mlx5_core_dev * dev,int func,bool ec_vf_func)46 static int mlx5_core_func_to_vport(const struct mlx5_core_dev *dev,
47 				   int func,
48 				   bool ec_vf_func)
49 {
50 	if (!ec_vf_func)
51 		return func;
52 	return mlx5_core_ec_vf_vport_base(dev) + func - 1;
53 }
54 
55 /**
56  * mlx5_get_default_msix_vec_count - Get the default number of MSI-X vectors
57  *                                   to be ssigned to each VF.
58  * @dev: PF to work on
59  * @num_vfs: Number of enabled VFs
60  */
mlx5_get_default_msix_vec_count(struct mlx5_core_dev * dev,int num_vfs)61 int mlx5_get_default_msix_vec_count(struct mlx5_core_dev *dev, int num_vfs)
62 {
63 	int num_vf_msix, min_msix, max_msix;
64 
65 	num_vf_msix = MLX5_CAP_GEN_MAX(dev, num_total_dynamic_vf_msix);
66 	if (!num_vf_msix)
67 		return 0;
68 
69 	min_msix = MLX5_CAP_GEN(dev, min_dynamic_vf_msix_table_size);
70 	max_msix = MLX5_CAP_GEN(dev, max_dynamic_vf_msix_table_size);
71 
72 	/* Limit maximum number of MSI-X vectors so the default configuration
73 	 * has some available in the pool. This will allow the user to increase
74 	 * the number of vectors in a VF without having to first size-down other
75 	 * VFs.
76 	 */
77 	return max(min(num_vf_msix / num_vfs, max_msix / 2), min_msix);
78 }
79 
80 /**
81  * mlx5_set_msix_vec_count - Set dynamically allocated MSI-X on the VF
82  * @dev: PF to work on
83  * @function_id: Internal PCI VF function IDd
84  * @msix_vec_count: Number of MSI-X vectors to set
85  */
mlx5_set_msix_vec_count(struct mlx5_core_dev * dev,int function_id,int msix_vec_count)86 int mlx5_set_msix_vec_count(struct mlx5_core_dev *dev, int function_id,
87 			    int msix_vec_count)
88 {
89 	int query_sz = MLX5_ST_SZ_BYTES(query_hca_cap_out);
90 	int set_sz = MLX5_ST_SZ_BYTES(set_hca_cap_in);
91 	void *hca_cap = NULL, *query_cap = NULL, *cap;
92 	int num_vf_msix, min_msix, max_msix;
93 	bool ec_vf_function;
94 	int vport;
95 	int ret;
96 
97 	num_vf_msix = MLX5_CAP_GEN_MAX(dev, num_total_dynamic_vf_msix);
98 	if (!num_vf_msix)
99 		return 0;
100 
101 	if (!MLX5_CAP_GEN(dev, vport_group_manager) || !mlx5_core_is_pf(dev))
102 		return -EOPNOTSUPP;
103 
104 	min_msix = MLX5_CAP_GEN(dev, min_dynamic_vf_msix_table_size);
105 	max_msix = MLX5_CAP_GEN(dev, max_dynamic_vf_msix_table_size);
106 
107 	if (msix_vec_count < min_msix)
108 		return -EINVAL;
109 
110 	if (msix_vec_count > max_msix)
111 		return -EOVERFLOW;
112 
113 	query_cap = kvzalloc(query_sz, GFP_KERNEL);
114 	hca_cap = kvzalloc(set_sz, GFP_KERNEL);
115 	if (!hca_cap || !query_cap) {
116 		ret = -ENOMEM;
117 		goto out;
118 	}
119 
120 	ec_vf_function = mlx5_core_ec_sriov_enabled(dev);
121 	vport = mlx5_core_func_to_vport(dev, function_id, ec_vf_function);
122 	ret = mlx5_vport_get_other_func_general_cap(dev, vport, query_cap);
123 	if (ret)
124 		goto out;
125 
126 	cap = MLX5_ADDR_OF(set_hca_cap_in, hca_cap, capability);
127 	memcpy(cap, MLX5_ADDR_OF(query_hca_cap_out, query_cap, capability),
128 	       MLX5_UN_SZ_BYTES(hca_cap_union));
129 	MLX5_SET(cmd_hca_cap, cap, dynamic_msix_table_size, msix_vec_count);
130 
131 	MLX5_SET(set_hca_cap_in, hca_cap, opcode, MLX5_CMD_OP_SET_HCA_CAP);
132 	MLX5_SET(set_hca_cap_in, hca_cap, other_function, 1);
133 	MLX5_SET(set_hca_cap_in, hca_cap, ec_vf_function, ec_vf_function);
134 	MLX5_SET(set_hca_cap_in, hca_cap, function_id, function_id);
135 
136 	MLX5_SET(set_hca_cap_in, hca_cap, op_mod,
137 		 MLX5_SET_HCA_CAP_OP_MOD_GENERAL_DEVICE << 1);
138 	ret = mlx5_cmd_exec_in(dev, set_hca_cap, hca_cap);
139 out:
140 	kvfree(hca_cap);
141 	kvfree(query_cap);
142 	return ret;
143 }
144 
145 /* mlx5_system_free_irq - Free an IRQ
146  * @irq: IRQ to free
147  *
148  * Free the IRQ and other resources such as rmap from the system.
149  * BUT doesn't free or remove reference from mlx5.
150  * This function is very important for the shutdown flow, where we need to
151  * cleanup system resoruces but keep mlx5 objects alive,
152  * see mlx5_irq_table_free_irqs().
153  */
mlx5_system_free_irq(struct mlx5_irq * irq)154 static void mlx5_system_free_irq(struct mlx5_irq *irq)
155 {
156 	struct mlx5_irq_pool *pool = irq->pool;
157 #ifdef CONFIG_RFS_ACCEL
158 	struct cpu_rmap *rmap;
159 #endif
160 
161 	/* free_irq requires that affinity_hint and rmap will be cleared before
162 	 * calling it. To satisfy this requirement, we call
163 	 * irq_cpu_rmap_remove() to remove the notifier
164 	 */
165 	irq_update_affinity_hint(irq->map.virq, NULL);
166 #ifdef CONFIG_RFS_ACCEL
167 	rmap = mlx5_eq_table_get_rmap(pool->dev);
168 	if (rmap)
169 		irq_cpu_rmap_remove(rmap, irq->map.virq);
170 #endif
171 
172 	free_irq(irq->map.virq, &irq->nh);
173 	if (irq->map.index && pci_msix_can_alloc_dyn(pool->dev->pdev))
174 		pci_msix_free_irq(pool->dev->pdev, irq->map);
175 }
176 
irq_release(struct mlx5_irq * irq)177 static void irq_release(struct mlx5_irq *irq)
178 {
179 	struct mlx5_irq_pool *pool = irq->pool;
180 
181 	xa_erase(&pool->irqs, irq->pool_index);
182 	mlx5_system_free_irq(irq);
183 	free_cpumask_var(irq->mask);
184 	kfree(irq);
185 }
186 
mlx5_irq_put(struct mlx5_irq * irq)187 int mlx5_irq_put(struct mlx5_irq *irq)
188 {
189 	struct mlx5_irq_pool *pool = irq->pool;
190 	int ret = 0;
191 
192 	mutex_lock(&pool->lock);
193 	irq->refcount--;
194 	if (!irq->refcount) {
195 		irq_release(irq);
196 		ret = 1;
197 	}
198 	mutex_unlock(&pool->lock);
199 	return ret;
200 }
201 
mlx5_irq_read_locked(struct mlx5_irq * irq)202 int mlx5_irq_read_locked(struct mlx5_irq *irq)
203 {
204 	lockdep_assert_held(&irq->pool->lock);
205 	return irq->refcount;
206 }
207 
mlx5_irq_get_locked(struct mlx5_irq * irq)208 int mlx5_irq_get_locked(struct mlx5_irq *irq)
209 {
210 	lockdep_assert_held(&irq->pool->lock);
211 	if (WARN_ON_ONCE(!irq->refcount))
212 		return 0;
213 	irq->refcount++;
214 	return 1;
215 }
216 
irq_get(struct mlx5_irq * irq)217 static int irq_get(struct mlx5_irq *irq)
218 {
219 	int err;
220 
221 	mutex_lock(&irq->pool->lock);
222 	err = mlx5_irq_get_locked(irq);
223 	mutex_unlock(&irq->pool->lock);
224 	return err;
225 }
226 
irq_int_handler(int irq,void * nh)227 static irqreturn_t irq_int_handler(int irq, void *nh)
228 {
229 	atomic_notifier_call_chain(nh, 0, NULL);
230 	return IRQ_HANDLED;
231 }
232 
irq_sf_set_name(struct mlx5_irq_pool * pool,char * name,int vecidx)233 static void irq_sf_set_name(struct mlx5_irq_pool *pool, char *name, int vecidx)
234 {
235 	snprintf(name, MLX5_MAX_IRQ_NAME, "%s%d", pool->name, vecidx);
236 }
237 
irq_set_name(struct mlx5_irq_pool * pool,char * name,int vecidx)238 static void irq_set_name(struct mlx5_irq_pool *pool, char *name, int vecidx)
239 {
240 	if (!pool->xa_num_irqs.max) {
241 		/* in case we only have a single irq for the device */
242 		snprintf(name, MLX5_MAX_IRQ_NAME, "mlx5_combined%d", vecidx);
243 		return;
244 	}
245 
246 	if (!vecidx) {
247 		snprintf(name, MLX5_MAX_IRQ_NAME, "mlx5_async%d", vecidx);
248 		return;
249 	}
250 
251 	vecidx -= MLX5_IRQ_VEC_COMP_BASE;
252 	snprintf(name, MLX5_MAX_IRQ_NAME, "mlx5_comp%d", vecidx);
253 }
254 
mlx5_irq_alloc(struct mlx5_irq_pool * pool,int i,struct irq_affinity_desc * af_desc,struct cpu_rmap ** rmap)255 struct mlx5_irq *mlx5_irq_alloc(struct mlx5_irq_pool *pool, int i,
256 				struct irq_affinity_desc *af_desc,
257 				struct cpu_rmap **rmap)
258 {
259 	struct mlx5_core_dev *dev = pool->dev;
260 	char name[MLX5_MAX_IRQ_NAME];
261 	struct mlx5_irq *irq;
262 	int err;
263 
264 	irq = kzalloc(sizeof(*irq), GFP_KERNEL);
265 	if (!irq || !zalloc_cpumask_var(&irq->mask, GFP_KERNEL)) {
266 		kfree(irq);
267 		return ERR_PTR(-ENOMEM);
268 	}
269 
270 	if (!i || !pci_msix_can_alloc_dyn(dev->pdev)) {
271 		/* The vector at index 0 is always statically allocated. If
272 		 * dynamic irq is not supported all vectors are statically
273 		 * allocated. In both cases just get the irq number and set
274 		 * the index.
275 		 */
276 		irq->map.virq = pci_irq_vector(dev->pdev, i);
277 		irq->map.index = i;
278 	} else {
279 		irq->map = pci_msix_alloc_irq_at(dev->pdev, MSI_ANY_INDEX, af_desc);
280 		if (!irq->map.virq) {
281 			err = irq->map.index;
282 			goto err_alloc_irq;
283 		}
284 	}
285 
286 	if (i && rmap && *rmap) {
287 #ifdef CONFIG_RFS_ACCEL
288 		err = irq_cpu_rmap_add(*rmap, irq->map.virq);
289 		if (err)
290 			goto err_irq_rmap;
291 #endif
292 	}
293 	if (!mlx5_irq_pool_is_sf_pool(pool))
294 		irq_set_name(pool, name, i);
295 	else
296 		irq_sf_set_name(pool, name, i);
297 	ATOMIC_INIT_NOTIFIER_HEAD(&irq->nh);
298 	snprintf(irq->name, MLX5_MAX_IRQ_FORMATTED_NAME,
299 		 MLX5_IRQ_NAME_FORMAT_STR, name, pci_name(dev->pdev));
300 	err = request_irq(irq->map.virq, irq_int_handler, 0, irq->name,
301 			  &irq->nh);
302 	if (err) {
303 		mlx5_core_err(dev, "Failed to request irq. err = %d\n", err);
304 		goto err_req_irq;
305 	}
306 
307 	if (af_desc) {
308 		cpumask_copy(irq->mask, &af_desc->mask);
309 		irq_set_affinity_and_hint(irq->map.virq, irq->mask);
310 	}
311 	irq->pool = pool;
312 	irq->refcount = 1;
313 	irq->pool_index = i;
314 	err = xa_err(xa_store(&pool->irqs, irq->pool_index, irq, GFP_KERNEL));
315 	if (err) {
316 		mlx5_core_err(dev, "Failed to alloc xa entry for irq(%u). err = %d\n",
317 			      irq->pool_index, err);
318 		goto err_xa;
319 	}
320 	return irq;
321 err_xa:
322 	if (af_desc)
323 		irq_update_affinity_hint(irq->map.virq, NULL);
324 	free_irq(irq->map.virq, &irq->nh);
325 err_req_irq:
326 #ifdef CONFIG_RFS_ACCEL
327 	if (i && rmap && *rmap) {
328 		free_irq_cpu_rmap(*rmap);
329 		*rmap = NULL;
330 	}
331 err_irq_rmap:
332 #endif
333 	if (i && pci_msix_can_alloc_dyn(dev->pdev))
334 		pci_msix_free_irq(dev->pdev, irq->map);
335 err_alloc_irq:
336 	free_cpumask_var(irq->mask);
337 	kfree(irq);
338 	return ERR_PTR(err);
339 }
340 
mlx5_irq_attach_nb(struct mlx5_irq * irq,struct notifier_block * nb)341 int mlx5_irq_attach_nb(struct mlx5_irq *irq, struct notifier_block *nb)
342 {
343 	int ret;
344 
345 	ret = irq_get(irq);
346 	if (!ret)
347 		/* Something very bad happens here, we are enabling EQ
348 		 * on non-existing IRQ.
349 		 */
350 		return -ENOENT;
351 	ret = atomic_notifier_chain_register(&irq->nh, nb);
352 	if (ret)
353 		mlx5_irq_put(irq);
354 	return ret;
355 }
356 
mlx5_irq_detach_nb(struct mlx5_irq * irq,struct notifier_block * nb)357 int mlx5_irq_detach_nb(struct mlx5_irq *irq, struct notifier_block *nb)
358 {
359 	int err = 0;
360 
361 	err = atomic_notifier_chain_unregister(&irq->nh, nb);
362 	mlx5_irq_put(irq);
363 	return err;
364 }
365 
mlx5_irq_get_affinity_mask(struct mlx5_irq * irq)366 struct cpumask *mlx5_irq_get_affinity_mask(struct mlx5_irq *irq)
367 {
368 	return irq->mask;
369 }
370 
mlx5_irq_get_irq(const struct mlx5_irq * irq)371 int mlx5_irq_get_irq(const struct mlx5_irq *irq)
372 {
373 	return irq->map.virq;
374 }
375 
mlx5_irq_get_index(struct mlx5_irq * irq)376 int mlx5_irq_get_index(struct mlx5_irq *irq)
377 {
378 	return irq->map.index;
379 }
380 
mlx5_irq_get_pool(struct mlx5_irq * irq)381 struct mlx5_irq_pool *mlx5_irq_get_pool(struct mlx5_irq *irq)
382 {
383 	return irq->pool;
384 }
385 
386 /* irq_pool API */
387 
388 /* requesting an irq from a given pool according to given index */
389 static struct mlx5_irq *
irq_pool_request_vector(struct mlx5_irq_pool * pool,int vecidx,struct irq_affinity_desc * af_desc,struct cpu_rmap ** rmap)390 irq_pool_request_vector(struct mlx5_irq_pool *pool, int vecidx,
391 			struct irq_affinity_desc *af_desc,
392 			struct cpu_rmap **rmap)
393 {
394 	struct mlx5_irq *irq;
395 
396 	mutex_lock(&pool->lock);
397 	irq = xa_load(&pool->irqs, vecidx);
398 	if (irq) {
399 		mlx5_irq_get_locked(irq);
400 		goto unlock;
401 	}
402 	irq = mlx5_irq_alloc(pool, vecidx, af_desc, rmap);
403 unlock:
404 	mutex_unlock(&pool->lock);
405 	return irq;
406 }
407 
sf_ctrl_irq_pool_get(struct mlx5_irq_table * irq_table)408 static struct mlx5_irq_pool *sf_ctrl_irq_pool_get(struct mlx5_irq_table *irq_table)
409 {
410 	return irq_table->sf_ctrl_pool;
411 }
412 
413 static struct mlx5_irq_pool *
sf_comp_irq_pool_get(struct mlx5_irq_table * irq_table)414 sf_comp_irq_pool_get(struct mlx5_irq_table *irq_table)
415 {
416 	return irq_table->sf_comp_pool;
417 }
418 
419 struct mlx5_irq_pool *
mlx5_irq_table_get_comp_irq_pool(struct mlx5_core_dev * dev)420 mlx5_irq_table_get_comp_irq_pool(struct mlx5_core_dev *dev)
421 {
422 	struct mlx5_irq_table *irq_table = mlx5_irq_table_get(dev);
423 	struct mlx5_irq_pool *pool = NULL;
424 
425 	if (mlx5_core_is_sf(dev))
426 		pool = sf_comp_irq_pool_get(irq_table);
427 
428 	/* In some configs, there won't be a pool of SFs IRQs. Hence, returning
429 	 * the PF IRQs pool in case the SF pool doesn't exist.
430 	 */
431 	return pool ? pool : irq_table->pcif_pool;
432 }
433 
ctrl_irq_pool_get(struct mlx5_core_dev * dev)434 static struct mlx5_irq_pool *ctrl_irq_pool_get(struct mlx5_core_dev *dev)
435 {
436 	struct mlx5_irq_table *irq_table = mlx5_irq_table_get(dev);
437 	struct mlx5_irq_pool *pool = NULL;
438 
439 	if (mlx5_core_is_sf(dev))
440 		pool = sf_ctrl_irq_pool_get(irq_table);
441 
442 	/* In some configs, there won't be a pool of SFs IRQs. Hence, returning
443 	 * the PF IRQs pool in case the SF pool doesn't exist.
444 	 */
445 	return pool ? pool : irq_table->pcif_pool;
446 }
447 
_mlx5_irq_release(struct mlx5_irq * irq)448 static void _mlx5_irq_release(struct mlx5_irq *irq)
449 {
450 	synchronize_irq(irq->map.virq);
451 	mlx5_irq_put(irq);
452 }
453 
454 /**
455  * mlx5_ctrl_irq_release - release a ctrl IRQ back to the system.
456  * @dev: mlx5 device that releasing the IRQ.
457  * @ctrl_irq: ctrl IRQ to be released.
458  */
mlx5_ctrl_irq_release(struct mlx5_core_dev * dev,struct mlx5_irq * ctrl_irq)459 void mlx5_ctrl_irq_release(struct mlx5_core_dev *dev, struct mlx5_irq *ctrl_irq)
460 {
461 	mlx5_irq_affinity_irq_release(dev, ctrl_irq);
462 }
463 
464 /**
465  * mlx5_ctrl_irq_request - request a ctrl IRQ for mlx5 device.
466  * @dev: mlx5 device that requesting the IRQ.
467  *
468  * This function returns a pointer to IRQ, or ERR_PTR in case of error.
469  */
mlx5_ctrl_irq_request(struct mlx5_core_dev * dev)470 struct mlx5_irq *mlx5_ctrl_irq_request(struct mlx5_core_dev *dev)
471 {
472 	struct mlx5_irq_pool *pool = ctrl_irq_pool_get(dev);
473 	struct irq_affinity_desc af_desc;
474 	struct mlx5_irq *irq;
475 
476 	cpumask_copy(&af_desc.mask, cpu_online_mask);
477 	af_desc.is_managed = false;
478 	if (!mlx5_irq_pool_is_sf_pool(pool)) {
479 		/* In case we are allocating a control IRQ from a pci device's pool.
480 		 * This can happen also for a SF if the SFs pool is empty.
481 		 */
482 		if (!pool->xa_num_irqs.max) {
483 			cpumask_clear(&af_desc.mask);
484 			/* In case we only have a single IRQ for PF/VF */
485 			cpumask_set_cpu(cpumask_first(cpu_online_mask), &af_desc.mask);
486 		}
487 		/* Allocate the IRQ in index 0. The vector was already allocated */
488 		irq = irq_pool_request_vector(pool, 0, &af_desc, NULL);
489 	} else {
490 		irq = mlx5_irq_affinity_request(dev, pool, &af_desc);
491 	}
492 
493 	return irq;
494 }
495 
496 /**
497  * mlx5_irq_request - request an IRQ for mlx5 PF/VF device.
498  * @dev: mlx5 device that requesting the IRQ.
499  * @vecidx: vector index of the IRQ. This argument is ignore if affinity is
500  * provided.
501  * @af_desc: affinity descriptor for this IRQ.
502  * @rmap: pointer to reverse map pointer for completion interrupts
503  *
504  * This function returns a pointer to IRQ, or ERR_PTR in case of error.
505  */
mlx5_irq_request(struct mlx5_core_dev * dev,u16 vecidx,struct irq_affinity_desc * af_desc,struct cpu_rmap ** rmap)506 struct mlx5_irq *mlx5_irq_request(struct mlx5_core_dev *dev, u16 vecidx,
507 				  struct irq_affinity_desc *af_desc,
508 				  struct cpu_rmap **rmap)
509 {
510 	struct mlx5_irq_table *irq_table = mlx5_irq_table_get(dev);
511 	struct mlx5_irq_pool *pool;
512 	struct mlx5_irq *irq;
513 
514 	pool = irq_table->pcif_pool;
515 	irq = irq_pool_request_vector(pool, vecidx, af_desc, rmap);
516 	if (IS_ERR(irq))
517 		return irq;
518 	mlx5_core_dbg(dev, "irq %u mapped to cpu %*pbl, %u EQs on this irq\n",
519 		      irq->map.virq, cpumask_pr_args(&af_desc->mask),
520 		      irq->refcount / MLX5_EQ_REFS_PER_IRQ);
521 	return irq;
522 }
523 
524 /**
525  * mlx5_irq_release_vector - release one IRQ back to the system.
526  * @irq: the irq to release.
527  */
mlx5_irq_release_vector(struct mlx5_irq * irq)528 void mlx5_irq_release_vector(struct mlx5_irq *irq)
529 {
530 	_mlx5_irq_release(irq);
531 }
532 
533 /**
534  * mlx5_irq_request_vector - request one IRQ for mlx5 device.
535  * @dev: mlx5 device that is requesting the IRQ.
536  * @cpu: CPU to bind the IRQ to.
537  * @vecidx: vector index to request an IRQ for.
538  * @rmap: pointer to reverse map pointer for completion interrupts
539  *
540  * Each IRQ is bound to at most 1 CPU.
541  * This function is requests one IRQ, for the given @vecidx.
542  *
543  * This function returns a pointer to the irq on success, or an error pointer
544  * in case of an error.
545  */
mlx5_irq_request_vector(struct mlx5_core_dev * dev,u16 cpu,u16 vecidx,struct cpu_rmap ** rmap)546 struct mlx5_irq *mlx5_irq_request_vector(struct mlx5_core_dev *dev, u16 cpu,
547 					 u16 vecidx, struct cpu_rmap **rmap)
548 {
549 	struct mlx5_irq_table *table = mlx5_irq_table_get(dev);
550 	struct mlx5_irq_pool *pool = table->pcif_pool;
551 	struct irq_affinity_desc af_desc;
552 	int offset = MLX5_IRQ_VEC_COMP_BASE;
553 
554 	if (!pool->xa_num_irqs.max)
555 		offset = 0;
556 
557 	af_desc.is_managed = false;
558 	cpumask_clear(&af_desc.mask);
559 	cpumask_set_cpu(cpu, &af_desc.mask);
560 	return mlx5_irq_request(dev, vecidx + offset, &af_desc, rmap);
561 }
562 
563 static struct mlx5_irq_pool *
irq_pool_alloc(struct mlx5_core_dev * dev,int start,int size,char * name,u32 min_threshold,u32 max_threshold)564 irq_pool_alloc(struct mlx5_core_dev *dev, int start, int size, char *name,
565 	       u32 min_threshold, u32 max_threshold)
566 {
567 	struct mlx5_irq_pool *pool = kvzalloc(sizeof(*pool), GFP_KERNEL);
568 
569 	if (!pool)
570 		return ERR_PTR(-ENOMEM);
571 	pool->dev = dev;
572 	mutex_init(&pool->lock);
573 	xa_init_flags(&pool->irqs, XA_FLAGS_ALLOC);
574 	pool->xa_num_irqs.min = start;
575 	pool->xa_num_irqs.max = start + size - 1;
576 	if (name)
577 		snprintf(pool->name, MLX5_MAX_IRQ_NAME - MLX5_MAX_IRQ_IDX_CHARS,
578 			 "%s", name);
579 	pool->min_threshold = min_threshold * MLX5_EQ_REFS_PER_IRQ;
580 	pool->max_threshold = max_threshold * MLX5_EQ_REFS_PER_IRQ;
581 	mlx5_core_dbg(dev, "pool->name = %s, pool->size = %d, pool->start = %d",
582 		      name ? name : "mlx5_pcif_pool", size, start);
583 	return pool;
584 }
585 
irq_pool_free(struct mlx5_irq_pool * pool)586 static void irq_pool_free(struct mlx5_irq_pool *pool)
587 {
588 	struct mlx5_irq *irq;
589 	unsigned long index;
590 
591 	/* There are cases in which we are destrying the irq_table before
592 	 * freeing all the IRQs, fast teardown for example. Hence, free the irqs
593 	 * which might not have been freed.
594 	 */
595 	xa_for_each(&pool->irqs, index, irq)
596 		irq_release(irq);
597 	xa_destroy(&pool->irqs);
598 	mutex_destroy(&pool->lock);
599 	kfree(pool->irqs_per_cpu);
600 	kvfree(pool);
601 }
602 
irq_pools_init(struct mlx5_core_dev * dev,int sf_vec,int pcif_vec,bool dynamic_vec)603 static int irq_pools_init(struct mlx5_core_dev *dev, int sf_vec, int pcif_vec,
604 			  bool dynamic_vec)
605 {
606 	struct mlx5_irq_table *table = dev->priv.irq_table;
607 	int sf_vec_available = sf_vec;
608 	int num_sf_ctrl;
609 	int err;
610 
611 	/* init pcif_pool */
612 	table->pcif_pool = irq_pool_alloc(dev, 0, pcif_vec, NULL,
613 					  MLX5_EQ_SHARE_IRQ_MIN_COMP,
614 					  MLX5_EQ_SHARE_IRQ_MAX_COMP);
615 	if (IS_ERR(table->pcif_pool))
616 		return PTR_ERR(table->pcif_pool);
617 	if (!mlx5_sf_max_functions(dev))
618 		return 0;
619 	if (sf_vec < MLX5_IRQ_VEC_COMP_BASE_SF) {
620 		mlx5_core_dbg(dev, "Not enught IRQs for SFs. SF may run at lower performance\n");
621 		return 0;
622 	}
623 
624 	/* init sf_ctrl_pool */
625 	num_sf_ctrl = DIV_ROUND_UP(mlx5_sf_max_functions(dev),
626 				   MLX5_SFS_PER_CTRL_IRQ);
627 	num_sf_ctrl = min_t(int, MLX5_IRQ_CTRL_SF_MAX, num_sf_ctrl);
628 	if (!dynamic_vec && (num_sf_ctrl + 1) > sf_vec_available) {
629 		mlx5_core_dbg(dev,
630 			      "Not enough IRQs for SFs control and completion pool, required=%d avail=%d\n",
631 			      num_sf_ctrl + 1, sf_vec_available);
632 		return 0;
633 	}
634 
635 	table->sf_ctrl_pool = irq_pool_alloc(dev, pcif_vec, num_sf_ctrl,
636 					     "mlx5_sf_ctrl",
637 					     MLX5_EQ_SHARE_IRQ_MIN_CTRL,
638 					     MLX5_EQ_SHARE_IRQ_MAX_CTRL);
639 	if (IS_ERR(table->sf_ctrl_pool)) {
640 		err = PTR_ERR(table->sf_ctrl_pool);
641 		goto err_pf;
642 	}
643 	sf_vec_available -= num_sf_ctrl;
644 
645 	/* init sf_comp_pool, remaining vectors are for the SF completions */
646 	table->sf_comp_pool = irq_pool_alloc(dev, pcif_vec + num_sf_ctrl,
647 					     sf_vec_available, "mlx5_sf_comp",
648 					     MLX5_EQ_SHARE_IRQ_MIN_COMP,
649 					     MLX5_EQ_SHARE_IRQ_MAX_COMP);
650 	if (IS_ERR(table->sf_comp_pool)) {
651 		err = PTR_ERR(table->sf_comp_pool);
652 		goto err_sf_ctrl;
653 	}
654 
655 	table->sf_comp_pool->irqs_per_cpu = kcalloc(nr_cpu_ids, sizeof(u16), GFP_KERNEL);
656 	if (!table->sf_comp_pool->irqs_per_cpu) {
657 		err = -ENOMEM;
658 		goto err_irqs_per_cpu;
659 	}
660 
661 	return 0;
662 
663 err_irqs_per_cpu:
664 	irq_pool_free(table->sf_comp_pool);
665 err_sf_ctrl:
666 	irq_pool_free(table->sf_ctrl_pool);
667 err_pf:
668 	irq_pool_free(table->pcif_pool);
669 	return err;
670 }
671 
irq_pools_destroy(struct mlx5_irq_table * table)672 static void irq_pools_destroy(struct mlx5_irq_table *table)
673 {
674 	if (table->sf_ctrl_pool) {
675 		irq_pool_free(table->sf_comp_pool);
676 		irq_pool_free(table->sf_ctrl_pool);
677 	}
678 	irq_pool_free(table->pcif_pool);
679 }
680 
mlx5_irq_pool_free_irqs(struct mlx5_irq_pool * pool)681 static void mlx5_irq_pool_free_irqs(struct mlx5_irq_pool *pool)
682 {
683 	struct mlx5_irq *irq;
684 	unsigned long index;
685 
686 	xa_for_each(&pool->irqs, index, irq)
687 		mlx5_system_free_irq(irq);
688 
689 }
690 
mlx5_irq_pools_free_irqs(struct mlx5_irq_table * table)691 static void mlx5_irq_pools_free_irqs(struct mlx5_irq_table *table)
692 {
693 	if (table->sf_ctrl_pool) {
694 		mlx5_irq_pool_free_irqs(table->sf_comp_pool);
695 		mlx5_irq_pool_free_irqs(table->sf_ctrl_pool);
696 	}
697 	mlx5_irq_pool_free_irqs(table->pcif_pool);
698 }
699 
700 /* irq_table API */
701 
mlx5_irq_table_init(struct mlx5_core_dev * dev)702 int mlx5_irq_table_init(struct mlx5_core_dev *dev)
703 {
704 	struct mlx5_irq_table *irq_table;
705 
706 	if (mlx5_core_is_sf(dev))
707 		return 0;
708 
709 	irq_table = kvzalloc_node(sizeof(*irq_table), GFP_KERNEL,
710 				  dev->priv.numa_node);
711 	if (!irq_table)
712 		return -ENOMEM;
713 
714 	dev->priv.irq_table = irq_table;
715 	return 0;
716 }
717 
mlx5_irq_table_cleanup(struct mlx5_core_dev * dev)718 void mlx5_irq_table_cleanup(struct mlx5_core_dev *dev)
719 {
720 	if (mlx5_core_is_sf(dev))
721 		return;
722 
723 	kvfree(dev->priv.irq_table);
724 }
725 
mlx5_irq_table_get_num_comp(struct mlx5_irq_table * table)726 int mlx5_irq_table_get_num_comp(struct mlx5_irq_table *table)
727 {
728 	if (!table->pcif_pool->xa_num_irqs.max)
729 		return 1;
730 	return table->pcif_pool->xa_num_irqs.max - table->pcif_pool->xa_num_irqs.min;
731 }
732 
mlx5_irq_table_create(struct mlx5_core_dev * dev)733 int mlx5_irq_table_create(struct mlx5_core_dev *dev)
734 {
735 	int num_eqs = mlx5_max_eq_cap_get(dev);
736 	bool dynamic_vec;
737 	int total_vec;
738 	int pcif_vec;
739 	int req_vec;
740 	int err;
741 	int n;
742 
743 	if (mlx5_core_is_sf(dev))
744 		return 0;
745 
746 	/* PCI PF vectors usage is limited by online cpus, device EQs and
747 	 * PCI MSI-X capability.
748 	 */
749 	pcif_vec = MLX5_CAP_GEN(dev, num_ports) * num_online_cpus() + 1;
750 	pcif_vec = min_t(int, pcif_vec, num_eqs);
751 	pcif_vec = min_t(int, pcif_vec, pci_msix_vec_count(dev->pdev));
752 
753 	total_vec = pcif_vec;
754 	if (mlx5_sf_max_functions(dev))
755 		total_vec += MLX5_MAX_MSIX_PER_SF * mlx5_sf_max_functions(dev);
756 	total_vec = min_t(int, total_vec, pci_msix_vec_count(dev->pdev));
757 
758 	req_vec = pci_msix_can_alloc_dyn(dev->pdev) ? 1 : total_vec;
759 	n = pci_alloc_irq_vectors(dev->pdev, 1, req_vec, PCI_IRQ_MSIX);
760 	if (n < 0)
761 		return n;
762 
763 	/* Further limit vectors of the pools based on platform for non dynamic case */
764 	dynamic_vec = pci_msix_can_alloc_dyn(dev->pdev);
765 	if (!dynamic_vec) {
766 		pcif_vec = min_t(int, n, pcif_vec);
767 		total_vec = min_t(int, n, total_vec);
768 	}
769 
770 	err = irq_pools_init(dev, total_vec - pcif_vec, pcif_vec, dynamic_vec);
771 	if (err)
772 		pci_free_irq_vectors(dev->pdev);
773 
774 	return err;
775 }
776 
mlx5_irq_table_destroy(struct mlx5_core_dev * dev)777 void mlx5_irq_table_destroy(struct mlx5_core_dev *dev)
778 {
779 	struct mlx5_irq_table *table = dev->priv.irq_table;
780 
781 	if (mlx5_core_is_sf(dev))
782 		return;
783 
784 	/* There are cases where IRQs still will be in used when we reaching
785 	 * to here. Hence, making sure all the irqs are released.
786 	 */
787 	irq_pools_destroy(table);
788 	pci_free_irq_vectors(dev->pdev);
789 }
790 
mlx5_irq_table_free_irqs(struct mlx5_core_dev * dev)791 void mlx5_irq_table_free_irqs(struct mlx5_core_dev *dev)
792 {
793 	struct mlx5_irq_table *table = dev->priv.irq_table;
794 
795 	if (mlx5_core_is_sf(dev))
796 		return;
797 
798 	mlx5_irq_pools_free_irqs(table);
799 	pci_free_irq_vectors(dev->pdev);
800 }
801 
mlx5_irq_table_get_sfs_vec(struct mlx5_irq_table * table)802 int mlx5_irq_table_get_sfs_vec(struct mlx5_irq_table *table)
803 {
804 	if (table->sf_comp_pool)
805 		return min_t(int, num_online_cpus(),
806 			     table->sf_comp_pool->xa_num_irqs.max -
807 			     table->sf_comp_pool->xa_num_irqs.min + 1);
808 	else
809 		return mlx5_irq_table_get_num_comp(table);
810 }
811 
mlx5_irq_table_get(struct mlx5_core_dev * dev)812 struct mlx5_irq_table *mlx5_irq_table_get(struct mlx5_core_dev *dev)
813 {
814 #ifdef CONFIG_MLX5_SF
815 	if (mlx5_core_is_sf(dev))
816 		return dev->priv.parent_mdev->priv.irq_table;
817 #endif
818 	return dev->priv.irq_table;
819 }
820