1 /*
2  * Copyright (c) 2013-2015, Mellanox Technologies. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/highmem.h>
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/delay.h>
37 #include <linux/mlx5/driver.h>
38 #include <linux/mlx5/cmd.h>
39 #include "mlx5_core.h"
40 
41 enum {
42 	MLX5_PAGES_CANT_GIVE	= 0,
43 	MLX5_PAGES_GIVE		= 1,
44 	MLX5_PAGES_TAKE		= 2
45 };
46 
47 struct mlx5_pages_req {
48 	struct mlx5_core_dev *dev;
49 	u16	func_id;
50 	s32	npages;
51 	struct work_struct work;
52 };
53 
54 struct fw_page {
55 	struct rb_node		rb_node;
56 	u64			addr;
57 	struct page	       *page;
58 	u16			func_id;
59 	unsigned long		bitmask;
60 	struct list_head	list;
61 	unsigned		free_count;
62 };
63 
64 enum {
65 	MAX_RECLAIM_TIME_MSECS	= 5000,
66 	MAX_RECLAIM_VFS_PAGES_TIME_MSECS = 2 * 1000 * 60,
67 };
68 
69 enum {
70 	MLX5_MAX_RECLAIM_TIME_MILI	= 5000,
71 	MLX5_NUM_4K_IN_PAGE		= PAGE_SIZE / MLX5_ADAPTER_PAGE_SIZE,
72 };
73 
insert_page(struct mlx5_core_dev * dev,u64 addr,struct page * page,u16 func_id)74 static int insert_page(struct mlx5_core_dev *dev, u64 addr, struct page *page, u16 func_id)
75 {
76 	struct rb_root *root = &dev->priv.page_root;
77 	struct rb_node **new = &root->rb_node;
78 	struct rb_node *parent = NULL;
79 	struct fw_page *nfp;
80 	struct fw_page *tfp;
81 	int i;
82 
83 	while (*new) {
84 		parent = *new;
85 		tfp = rb_entry(parent, struct fw_page, rb_node);
86 		if (tfp->addr < addr)
87 			new = &parent->rb_left;
88 		else if (tfp->addr > addr)
89 			new = &parent->rb_right;
90 		else
91 			return -EEXIST;
92 	}
93 
94 	nfp = kzalloc(sizeof(*nfp), GFP_KERNEL);
95 	if (!nfp)
96 		return -ENOMEM;
97 
98 	nfp->addr = addr;
99 	nfp->page = page;
100 	nfp->func_id = func_id;
101 	nfp->free_count = MLX5_NUM_4K_IN_PAGE;
102 	for (i = 0; i < MLX5_NUM_4K_IN_PAGE; i++)
103 		set_bit(i, &nfp->bitmask);
104 
105 	rb_link_node(&nfp->rb_node, parent, new);
106 	rb_insert_color(&nfp->rb_node, root);
107 	list_add(&nfp->list, &dev->priv.free_list);
108 
109 	return 0;
110 }
111 
find_fw_page(struct mlx5_core_dev * dev,u64 addr)112 static struct fw_page *find_fw_page(struct mlx5_core_dev *dev, u64 addr)
113 {
114 	struct rb_root *root = &dev->priv.page_root;
115 	struct rb_node *tmp = root->rb_node;
116 	struct fw_page *result = NULL;
117 	struct fw_page *tfp;
118 
119 	while (tmp) {
120 		tfp = rb_entry(tmp, struct fw_page, rb_node);
121 		if (tfp->addr < addr) {
122 			tmp = tmp->rb_left;
123 		} else if (tfp->addr > addr) {
124 			tmp = tmp->rb_right;
125 		} else {
126 			result = tfp;
127 			break;
128 		}
129 	}
130 
131 	return result;
132 }
133 
mlx5_cmd_query_pages(struct mlx5_core_dev * dev,u16 * func_id,s32 * npages,int boot)134 static int mlx5_cmd_query_pages(struct mlx5_core_dev *dev, u16 *func_id,
135 				s32 *npages, int boot)
136 {
137 	u32 out[MLX5_ST_SZ_DW(query_pages_out)] = {0};
138 	u32 in[MLX5_ST_SZ_DW(query_pages_in)]   = {0};
139 	int err;
140 
141 	MLX5_SET(query_pages_in, in, opcode, MLX5_CMD_OP_QUERY_PAGES);
142 	MLX5_SET(query_pages_in, in, op_mod, boot ?
143 		 MLX5_QUERY_PAGES_IN_OP_MOD_BOOT_PAGES :
144 		 MLX5_QUERY_PAGES_IN_OP_MOD_INIT_PAGES);
145 
146 	err = mlx5_cmd_exec(dev, in, sizeof(in), out, sizeof(out));
147 	if (err)
148 		return err;
149 
150 	*npages = MLX5_GET(query_pages_out, out, num_pages);
151 	*func_id = MLX5_GET(query_pages_out, out, function_id);
152 
153 	return err;
154 }
155 
alloc_4k(struct mlx5_core_dev * dev,u64 * addr)156 static int alloc_4k(struct mlx5_core_dev *dev, u64 *addr)
157 {
158 	struct fw_page *fp;
159 	unsigned n;
160 
161 	if (list_empty(&dev->priv.free_list))
162 		return -ENOMEM;
163 
164 	fp = list_entry(dev->priv.free_list.next, struct fw_page, list);
165 	n = find_first_bit(&fp->bitmask, 8 * sizeof(fp->bitmask));
166 	if (n >= MLX5_NUM_4K_IN_PAGE) {
167 		mlx5_core_warn(dev, "alloc 4k bug\n");
168 		return -ENOENT;
169 	}
170 	clear_bit(n, &fp->bitmask);
171 	fp->free_count--;
172 	if (!fp->free_count)
173 		list_del(&fp->list);
174 
175 	*addr = fp->addr + n * MLX5_ADAPTER_PAGE_SIZE;
176 
177 	return 0;
178 }
179 
180 #define MLX5_U64_4K_PAGE_MASK ((~(u64)0U) << PAGE_SHIFT)
181 
free_4k(struct mlx5_core_dev * dev,u64 addr)182 static void free_4k(struct mlx5_core_dev *dev, u64 addr)
183 {
184 	struct fw_page *fwp;
185 	int n;
186 
187 	fwp = find_fw_page(dev, addr & MLX5_U64_4K_PAGE_MASK);
188 	if (!fwp) {
189 		mlx5_core_warn(dev, "page not found\n");
190 		return;
191 	}
192 
193 	n = (addr & ~MLX5_U64_4K_PAGE_MASK) >> MLX5_ADAPTER_PAGE_SHIFT;
194 	fwp->free_count++;
195 	set_bit(n, &fwp->bitmask);
196 	if (fwp->free_count == MLX5_NUM_4K_IN_PAGE) {
197 		rb_erase(&fwp->rb_node, &dev->priv.page_root);
198 		if (fwp->free_count != 1)
199 			list_del(&fwp->list);
200 		dma_unmap_page(&dev->pdev->dev, addr & MLX5_U64_4K_PAGE_MASK,
201 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
202 		__free_page(fwp->page);
203 		kfree(fwp);
204 	} else if (fwp->free_count == 1) {
205 		list_add(&fwp->list, &dev->priv.free_list);
206 	}
207 }
208 
alloc_system_page(struct mlx5_core_dev * dev,u16 func_id)209 static int alloc_system_page(struct mlx5_core_dev *dev, u16 func_id)
210 {
211 	struct page *page;
212 	u64 zero_addr = 1;
213 	u64 addr;
214 	int err;
215 	int nid = dev_to_node(&dev->pdev->dev);
216 
217 	page = alloc_pages_node(nid, GFP_HIGHUSER, 0);
218 	if (!page) {
219 		mlx5_core_warn(dev, "failed to allocate page\n");
220 		return -ENOMEM;
221 	}
222 map:
223 	addr = dma_map_page(&dev->pdev->dev, page, 0,
224 			    PAGE_SIZE, DMA_BIDIRECTIONAL);
225 	if (dma_mapping_error(&dev->pdev->dev, addr)) {
226 		mlx5_core_warn(dev, "failed dma mapping page\n");
227 		err = -ENOMEM;
228 		goto err_mapping;
229 	}
230 
231 	/* Firmware doesn't support page with physical address 0 */
232 	if (addr == 0) {
233 		zero_addr = addr;
234 		goto map;
235 	}
236 
237 	err = insert_page(dev, addr, page, func_id);
238 	if (err) {
239 		mlx5_core_err(dev, "failed to track allocated page\n");
240 		dma_unmap_page(&dev->pdev->dev, addr, PAGE_SIZE,
241 			       DMA_BIDIRECTIONAL);
242 	}
243 
244 err_mapping:
245 	if (err)
246 		__free_page(page);
247 
248 	if (zero_addr == 0)
249 		dma_unmap_page(&dev->pdev->dev, zero_addr, PAGE_SIZE,
250 			       DMA_BIDIRECTIONAL);
251 
252 	return err;
253 }
254 
page_notify_fail(struct mlx5_core_dev * dev,u16 func_id)255 static void page_notify_fail(struct mlx5_core_dev *dev, u16 func_id)
256 {
257 	u32 out[MLX5_ST_SZ_DW(manage_pages_out)] = {0};
258 	u32 in[MLX5_ST_SZ_DW(manage_pages_in)]   = {0};
259 	int err;
260 
261 	MLX5_SET(manage_pages_in, in, opcode, MLX5_CMD_OP_MANAGE_PAGES);
262 	MLX5_SET(manage_pages_in, in, op_mod, MLX5_PAGES_CANT_GIVE);
263 	MLX5_SET(manage_pages_in, in, function_id, func_id);
264 
265 	err = mlx5_cmd_exec(dev, in, sizeof(in), out, sizeof(out));
266 	if (err)
267 		mlx5_core_warn(dev, "page notify failed func_id(%d) err(%d)\n",
268 			       func_id, err);
269 }
270 
give_pages(struct mlx5_core_dev * dev,u16 func_id,int npages,int notify_fail)271 static int give_pages(struct mlx5_core_dev *dev, u16 func_id, int npages,
272 		      int notify_fail)
273 {
274 	u32 out[MLX5_ST_SZ_DW(manage_pages_out)] = {0};
275 	int inlen = MLX5_ST_SZ_BYTES(manage_pages_in);
276 	u64 addr;
277 	int err;
278 	u32 *in;
279 	int i;
280 
281 	inlen += npages * MLX5_FLD_SZ_BYTES(manage_pages_in, pas[0]);
282 	in = kvzalloc(inlen, GFP_KERNEL);
283 	if (!in) {
284 		err = -ENOMEM;
285 		mlx5_core_warn(dev, "vzalloc failed %d\n", inlen);
286 		goto out_free;
287 	}
288 
289 	for (i = 0; i < npages; i++) {
290 retry:
291 		err = alloc_4k(dev, &addr);
292 		if (err) {
293 			if (err == -ENOMEM)
294 				err = alloc_system_page(dev, func_id);
295 			if (err)
296 				goto out_4k;
297 
298 			goto retry;
299 		}
300 		MLX5_ARRAY_SET64(manage_pages_in, in, pas, i, addr);
301 	}
302 
303 	MLX5_SET(manage_pages_in, in, opcode, MLX5_CMD_OP_MANAGE_PAGES);
304 	MLX5_SET(manage_pages_in, in, op_mod, MLX5_PAGES_GIVE);
305 	MLX5_SET(manage_pages_in, in, function_id, func_id);
306 	MLX5_SET(manage_pages_in, in, input_num_entries, npages);
307 
308 	err = mlx5_cmd_exec(dev, in, inlen, out, sizeof(out));
309 	if (err) {
310 		mlx5_core_warn(dev, "func_id 0x%x, npages %d, err %d\n",
311 			       func_id, npages, err);
312 		goto out_4k;
313 	}
314 
315 	dev->priv.fw_pages += npages;
316 	if (func_id)
317 		dev->priv.vfs_pages += npages;
318 
319 	mlx5_core_dbg(dev, "err %d\n", err);
320 
321 	kvfree(in);
322 	return 0;
323 
324 out_4k:
325 	for (i--; i >= 0; i--)
326 		free_4k(dev, MLX5_GET64(manage_pages_in, in, pas[i]));
327 out_free:
328 	kvfree(in);
329 	if (notify_fail)
330 		page_notify_fail(dev, func_id);
331 	return err;
332 }
333 
reclaim_pages_cmd(struct mlx5_core_dev * dev,u32 * in,int in_size,u32 * out,int out_size)334 static int reclaim_pages_cmd(struct mlx5_core_dev *dev,
335 			     u32 *in, int in_size, u32 *out, int out_size)
336 {
337 	struct fw_page *fwp;
338 	struct rb_node *p;
339 	u32 func_id;
340 	u32 npages;
341 	u32 i = 0;
342 
343 	if (dev->state != MLX5_DEVICE_STATE_INTERNAL_ERROR)
344 		return mlx5_cmd_exec(dev, in, in_size, out, out_size);
345 
346 	/* No hard feelings, we want our pages back! */
347 	npages = MLX5_GET(manage_pages_in, in, input_num_entries);
348 	func_id = MLX5_GET(manage_pages_in, in, function_id);
349 
350 	p = rb_first(&dev->priv.page_root);
351 	while (p && i < npages) {
352 		fwp = rb_entry(p, struct fw_page, rb_node);
353 		p = rb_next(p);
354 		if (fwp->func_id != func_id)
355 			continue;
356 
357 		MLX5_ARRAY_SET64(manage_pages_out, out, pas, i, fwp->addr);
358 		i++;
359 	}
360 
361 	MLX5_SET(manage_pages_out, out, output_num_entries, i);
362 	return 0;
363 }
364 
reclaim_pages(struct mlx5_core_dev * dev,u32 func_id,int npages,int * nclaimed)365 static int reclaim_pages(struct mlx5_core_dev *dev, u32 func_id, int npages,
366 			 int *nclaimed)
367 {
368 	int outlen = MLX5_ST_SZ_BYTES(manage_pages_out);
369 	u32 in[MLX5_ST_SZ_DW(manage_pages_in)] = {0};
370 	int num_claimed;
371 	u32 *out;
372 	int err;
373 	int i;
374 
375 	if (nclaimed)
376 		*nclaimed = 0;
377 
378 	outlen += npages * MLX5_FLD_SZ_BYTES(manage_pages_out, pas[0]);
379 	out = kvzalloc(outlen, GFP_KERNEL);
380 	if (!out)
381 		return -ENOMEM;
382 
383 	MLX5_SET(manage_pages_in, in, opcode, MLX5_CMD_OP_MANAGE_PAGES);
384 	MLX5_SET(manage_pages_in, in, op_mod, MLX5_PAGES_TAKE);
385 	MLX5_SET(manage_pages_in, in, function_id, func_id);
386 	MLX5_SET(manage_pages_in, in, input_num_entries, npages);
387 
388 	mlx5_core_dbg(dev, "npages %d, outlen %d\n", npages, outlen);
389 	err = reclaim_pages_cmd(dev, in, sizeof(in), out, outlen);
390 	if (err) {
391 		mlx5_core_err(dev, "failed reclaiming pages: err %d\n", err);
392 		goto out_free;
393 	}
394 
395 	num_claimed = MLX5_GET(manage_pages_out, out, output_num_entries);
396 	if (num_claimed > npages) {
397 		mlx5_core_warn(dev, "fw returned %d, driver asked %d => corruption\n",
398 			       num_claimed, npages);
399 		err = -EINVAL;
400 		goto out_free;
401 	}
402 
403 	for (i = 0; i < num_claimed; i++)
404 		free_4k(dev, MLX5_GET64(manage_pages_out, out, pas[i]));
405 
406 	if (nclaimed)
407 		*nclaimed = num_claimed;
408 
409 	dev->priv.fw_pages -= num_claimed;
410 	if (func_id)
411 		dev->priv.vfs_pages -= num_claimed;
412 
413 out_free:
414 	kvfree(out);
415 	return err;
416 }
417 
pages_work_handler(struct work_struct * work)418 static void pages_work_handler(struct work_struct *work)
419 {
420 	struct mlx5_pages_req *req = container_of(work, struct mlx5_pages_req, work);
421 	struct mlx5_core_dev *dev = req->dev;
422 	int err = 0;
423 
424 	if (req->npages < 0)
425 		err = reclaim_pages(dev, req->func_id, -1 * req->npages, NULL);
426 	else if (req->npages > 0)
427 		err = give_pages(dev, req->func_id, req->npages, 1);
428 
429 	if (err)
430 		mlx5_core_warn(dev, "%s fail %d\n",
431 			       req->npages < 0 ? "reclaim" : "give", err);
432 
433 	kfree(req);
434 }
435 
mlx5_core_req_pages_handler(struct mlx5_core_dev * dev,u16 func_id,s32 npages)436 void mlx5_core_req_pages_handler(struct mlx5_core_dev *dev, u16 func_id,
437 				 s32 npages)
438 {
439 	struct mlx5_pages_req *req;
440 
441 	req = kzalloc(sizeof(*req), GFP_ATOMIC);
442 	if (!req) {
443 		mlx5_core_warn(dev, "failed to allocate pages request\n");
444 		return;
445 	}
446 
447 	req->dev = dev;
448 	req->func_id = func_id;
449 	req->npages = npages;
450 	INIT_WORK(&req->work, pages_work_handler);
451 	queue_work(dev->priv.pg_wq, &req->work);
452 }
453 
mlx5_satisfy_startup_pages(struct mlx5_core_dev * dev,int boot)454 int mlx5_satisfy_startup_pages(struct mlx5_core_dev *dev, int boot)
455 {
456 	u16 uninitialized_var(func_id);
457 	s32 uninitialized_var(npages);
458 	int err;
459 
460 	err = mlx5_cmd_query_pages(dev, &func_id, &npages, boot);
461 	if (err)
462 		return err;
463 
464 	mlx5_core_dbg(dev, "requested %d %s pages for func_id 0x%x\n",
465 		      npages, boot ? "boot" : "init", func_id);
466 
467 	return give_pages(dev, func_id, npages, 0);
468 }
469 
470 enum {
471 	MLX5_BLKS_FOR_RECLAIM_PAGES = 12
472 };
473 
optimal_reclaimed_pages(void)474 static int optimal_reclaimed_pages(void)
475 {
476 	struct mlx5_cmd_prot_block *block;
477 	struct mlx5_cmd_layout *lay;
478 	int ret;
479 
480 	ret = (sizeof(lay->out) + MLX5_BLKS_FOR_RECLAIM_PAGES * sizeof(block->data) -
481 	       MLX5_ST_SZ_BYTES(manage_pages_out)) /
482 	       MLX5_FLD_SZ_BYTES(manage_pages_out, pas[0]);
483 
484 	return ret;
485 }
486 
mlx5_reclaim_startup_pages(struct mlx5_core_dev * dev)487 int mlx5_reclaim_startup_pages(struct mlx5_core_dev *dev)
488 {
489 	unsigned long end = jiffies + msecs_to_jiffies(MAX_RECLAIM_TIME_MSECS);
490 	struct fw_page *fwp;
491 	struct rb_node *p;
492 	int nclaimed = 0;
493 	int err = 0;
494 
495 	do {
496 		p = rb_first(&dev->priv.page_root);
497 		if (p) {
498 			fwp = rb_entry(p, struct fw_page, rb_node);
499 			err = reclaim_pages(dev, fwp->func_id,
500 					    optimal_reclaimed_pages(),
501 					    &nclaimed);
502 
503 			if (err) {
504 				mlx5_core_warn(dev, "failed reclaiming pages (%d)\n",
505 					       err);
506 				return err;
507 			}
508 			if (nclaimed)
509 				end = jiffies + msecs_to_jiffies(MAX_RECLAIM_TIME_MSECS);
510 		}
511 		if (time_after(jiffies, end)) {
512 			mlx5_core_warn(dev, "FW did not return all pages. giving up...\n");
513 			break;
514 		}
515 	} while (p);
516 
517 	WARN(dev->priv.fw_pages,
518 	     "FW pages counter is %d after reclaiming all pages\n",
519 	     dev->priv.fw_pages);
520 	WARN(dev->priv.vfs_pages,
521 	     "VFs FW pages counter is %d after reclaiming all pages\n",
522 	     dev->priv.vfs_pages);
523 
524 	return 0;
525 }
526 
mlx5_pagealloc_init(struct mlx5_core_dev * dev)527 void mlx5_pagealloc_init(struct mlx5_core_dev *dev)
528 {
529 	dev->priv.page_root = RB_ROOT;
530 	INIT_LIST_HEAD(&dev->priv.free_list);
531 }
532 
mlx5_pagealloc_cleanup(struct mlx5_core_dev * dev)533 void mlx5_pagealloc_cleanup(struct mlx5_core_dev *dev)
534 {
535 	/* nothing */
536 }
537 
mlx5_pagealloc_start(struct mlx5_core_dev * dev)538 int mlx5_pagealloc_start(struct mlx5_core_dev *dev)
539 {
540 	dev->priv.pg_wq = create_singlethread_workqueue("mlx5_page_allocator");
541 	if (!dev->priv.pg_wq)
542 		return -ENOMEM;
543 
544 	return 0;
545 }
546 
mlx5_pagealloc_stop(struct mlx5_core_dev * dev)547 void mlx5_pagealloc_stop(struct mlx5_core_dev *dev)
548 {
549 	destroy_workqueue(dev->priv.pg_wq);
550 }
551 
mlx5_wait_for_vf_pages(struct mlx5_core_dev * dev)552 int mlx5_wait_for_vf_pages(struct mlx5_core_dev *dev)
553 {
554 	unsigned long end = jiffies + msecs_to_jiffies(MAX_RECLAIM_VFS_PAGES_TIME_MSECS);
555 	int prev_vfs_pages = dev->priv.vfs_pages;
556 
557 	/* In case of internal error we will free the pages manually later */
558 	if (dev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR) {
559 		mlx5_core_warn(dev, "Skipping wait for vf pages stage");
560 		return 0;
561 	}
562 
563 	mlx5_core_dbg(dev, "Waiting for %d pages from %s\n", prev_vfs_pages,
564 		      dev->priv.name);
565 	while (dev->priv.vfs_pages) {
566 		if (time_after(jiffies, end)) {
567 			mlx5_core_warn(dev, "aborting while there are %d pending pages\n", dev->priv.vfs_pages);
568 			return -ETIMEDOUT;
569 		}
570 		if (dev->priv.vfs_pages < prev_vfs_pages) {
571 			end = jiffies + msecs_to_jiffies(MAX_RECLAIM_VFS_PAGES_TIME_MSECS);
572 			prev_vfs_pages = dev->priv.vfs_pages;
573 		}
574 		msleep(50);
575 	}
576 
577 	mlx5_core_dbg(dev, "All pages received from %s\n", dev->priv.name);
578 	return 0;
579 }
580