xref: /linux/drivers/cxl/pmem.c (revision c7546e2c3cb739a3c1a2f5acaf9bb629d401afe5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright(c) 2021 Intel Corporation. All rights reserved. */
3 #include <linux/libnvdimm.h>
4 #include <asm/unaligned.h>
5 #include <linux/device.h>
6 #include <linux/module.h>
7 #include <linux/ndctl.h>
8 #include <linux/async.h>
9 #include <linux/slab.h>
10 #include <linux/nd.h>
11 #include "cxlmem.h"
12 #include "cxl.h"
13 
14 static __read_mostly DECLARE_BITMAP(exclusive_cmds, CXL_MEM_COMMAND_ID_MAX);
15 
16 static void clear_exclusive(void *mds)
17 {
18 	clear_exclusive_cxl_commands(mds, exclusive_cmds);
19 }
20 
21 static void unregister_nvdimm(void *nvdimm)
22 {
23 	nvdimm_delete(nvdimm);
24 }
25 
26 static ssize_t provider_show(struct device *dev, struct device_attribute *attr, char *buf)
27 {
28 	struct nvdimm *nvdimm = to_nvdimm(dev);
29 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
30 
31 	return sysfs_emit(buf, "%s\n", dev_name(&cxl_nvd->dev));
32 }
33 static DEVICE_ATTR_RO(provider);
34 
35 static ssize_t id_show(struct device *dev, struct device_attribute *attr, char *buf)
36 {
37 	struct nvdimm *nvdimm = to_nvdimm(dev);
38 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
39 	struct cxl_dev_state *cxlds = cxl_nvd->cxlmd->cxlds;
40 
41 	return sysfs_emit(buf, "%lld\n", cxlds->serial);
42 }
43 static DEVICE_ATTR_RO(id);
44 
45 static struct attribute *cxl_dimm_attributes[] = {
46 	&dev_attr_id.attr,
47 	&dev_attr_provider.attr,
48 	NULL
49 };
50 
51 static const struct attribute_group cxl_dimm_attribute_group = {
52 	.name = "cxl",
53 	.attrs = cxl_dimm_attributes,
54 };
55 
56 static const struct attribute_group *cxl_dimm_attribute_groups[] = {
57 	&cxl_dimm_attribute_group,
58 	NULL
59 };
60 
61 static int cxl_nvdimm_probe(struct device *dev)
62 {
63 	struct cxl_nvdimm *cxl_nvd = to_cxl_nvdimm(dev);
64 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
65 	struct cxl_nvdimm_bridge *cxl_nvb = cxlmd->cxl_nvb;
66 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
67 	unsigned long flags = 0, cmd_mask = 0;
68 	struct nvdimm *nvdimm;
69 	int rc;
70 
71 	set_exclusive_cxl_commands(mds, exclusive_cmds);
72 	rc = devm_add_action_or_reset(dev, clear_exclusive, mds);
73 	if (rc)
74 		return rc;
75 
76 	set_bit(NDD_LABELING, &flags);
77 	set_bit(NDD_REGISTER_SYNC, &flags);
78 	set_bit(ND_CMD_GET_CONFIG_SIZE, &cmd_mask);
79 	set_bit(ND_CMD_GET_CONFIG_DATA, &cmd_mask);
80 	set_bit(ND_CMD_SET_CONFIG_DATA, &cmd_mask);
81 	nvdimm = __nvdimm_create(cxl_nvb->nvdimm_bus, cxl_nvd,
82 				 cxl_dimm_attribute_groups, flags,
83 				 cmd_mask, 0, NULL, cxl_nvd->dev_id,
84 				 cxl_security_ops, NULL);
85 	if (!nvdimm)
86 		return -ENOMEM;
87 
88 	dev_set_drvdata(dev, nvdimm);
89 	return devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm);
90 }
91 
92 static struct cxl_driver cxl_nvdimm_driver = {
93 	.name = "cxl_nvdimm",
94 	.probe = cxl_nvdimm_probe,
95 	.id = CXL_DEVICE_NVDIMM,
96 	.drv = {
97 		.suppress_bind_attrs = true,
98 	},
99 };
100 
101 static int cxl_pmem_get_config_size(struct cxl_memdev_state *mds,
102 				    struct nd_cmd_get_config_size *cmd,
103 				    unsigned int buf_len)
104 {
105 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
106 
107 	if (sizeof(*cmd) > buf_len)
108 		return -EINVAL;
109 
110 	*cmd = (struct nd_cmd_get_config_size){
111 		.config_size = mds->lsa_size,
112 		.max_xfer =
113 			cxl_mbox->payload_size - sizeof(struct cxl_mbox_set_lsa),
114 	};
115 
116 	return 0;
117 }
118 
119 static int cxl_pmem_get_config_data(struct cxl_memdev_state *mds,
120 				    struct nd_cmd_get_config_data_hdr *cmd,
121 				    unsigned int buf_len)
122 {
123 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
124 	struct cxl_mbox_get_lsa get_lsa;
125 	struct cxl_mbox_cmd mbox_cmd;
126 	int rc;
127 
128 	if (sizeof(*cmd) > buf_len)
129 		return -EINVAL;
130 	if (struct_size(cmd, out_buf, cmd->in_length) > buf_len)
131 		return -EINVAL;
132 
133 	get_lsa = (struct cxl_mbox_get_lsa) {
134 		.offset = cpu_to_le32(cmd->in_offset),
135 		.length = cpu_to_le32(cmd->in_length),
136 	};
137 	mbox_cmd = (struct cxl_mbox_cmd) {
138 		.opcode = CXL_MBOX_OP_GET_LSA,
139 		.payload_in = &get_lsa,
140 		.size_in = sizeof(get_lsa),
141 		.size_out = cmd->in_length,
142 		.payload_out = cmd->out_buf,
143 	};
144 
145 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
146 	cmd->status = 0;
147 
148 	return rc;
149 }
150 
151 static int cxl_pmem_set_config_data(struct cxl_memdev_state *mds,
152 				    struct nd_cmd_set_config_hdr *cmd,
153 				    unsigned int buf_len)
154 {
155 	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
156 	struct cxl_mbox_set_lsa *set_lsa;
157 	struct cxl_mbox_cmd mbox_cmd;
158 	int rc;
159 
160 	if (sizeof(*cmd) > buf_len)
161 		return -EINVAL;
162 
163 	/* 4-byte status follows the input data in the payload */
164 	if (size_add(struct_size(cmd, in_buf, cmd->in_length), 4) > buf_len)
165 		return -EINVAL;
166 
167 	set_lsa =
168 		kvzalloc(struct_size(set_lsa, data, cmd->in_length), GFP_KERNEL);
169 	if (!set_lsa)
170 		return -ENOMEM;
171 
172 	*set_lsa = (struct cxl_mbox_set_lsa) {
173 		.offset = cpu_to_le32(cmd->in_offset),
174 	};
175 	memcpy(set_lsa->data, cmd->in_buf, cmd->in_length);
176 	mbox_cmd = (struct cxl_mbox_cmd) {
177 		.opcode = CXL_MBOX_OP_SET_LSA,
178 		.payload_in = set_lsa,
179 		.size_in = struct_size(set_lsa, data, cmd->in_length),
180 	};
181 
182 	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
183 
184 	/*
185 	 * Set "firmware" status (4-packed bytes at the end of the input
186 	 * payload.
187 	 */
188 	put_unaligned(0, (u32 *) &cmd->in_buf[cmd->in_length]);
189 	kvfree(set_lsa);
190 
191 	return rc;
192 }
193 
194 static int cxl_pmem_nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd,
195 			       void *buf, unsigned int buf_len)
196 {
197 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
198 	unsigned long cmd_mask = nvdimm_cmd_mask(nvdimm);
199 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
200 	struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds);
201 
202 	if (!test_bit(cmd, &cmd_mask))
203 		return -ENOTTY;
204 
205 	switch (cmd) {
206 	case ND_CMD_GET_CONFIG_SIZE:
207 		return cxl_pmem_get_config_size(mds, buf, buf_len);
208 	case ND_CMD_GET_CONFIG_DATA:
209 		return cxl_pmem_get_config_data(mds, buf, buf_len);
210 	case ND_CMD_SET_CONFIG_DATA:
211 		return cxl_pmem_set_config_data(mds, buf, buf_len);
212 	default:
213 		return -ENOTTY;
214 	}
215 }
216 
217 static int cxl_pmem_ctl(struct nvdimm_bus_descriptor *nd_desc,
218 			struct nvdimm *nvdimm, unsigned int cmd, void *buf,
219 			unsigned int buf_len, int *cmd_rc)
220 {
221 	/*
222 	 * No firmware response to translate, let the transport error
223 	 * code take precedence.
224 	 */
225 	*cmd_rc = 0;
226 
227 	if (!nvdimm)
228 		return -ENOTTY;
229 	return cxl_pmem_nvdimm_ctl(nvdimm, cmd, buf, buf_len);
230 }
231 
232 static int detach_nvdimm(struct device *dev, void *data)
233 {
234 	struct cxl_nvdimm *cxl_nvd;
235 	bool release = false;
236 
237 	if (!is_cxl_nvdimm(dev))
238 		return 0;
239 
240 	scoped_guard(device, dev) {
241 		if (dev->driver) {
242 			cxl_nvd = to_cxl_nvdimm(dev);
243 			if (cxl_nvd->cxlmd && cxl_nvd->cxlmd->cxl_nvb == data)
244 				release = true;
245 		}
246 	}
247 	if (release)
248 		device_release_driver(dev);
249 	return 0;
250 }
251 
252 static void unregister_nvdimm_bus(void *_cxl_nvb)
253 {
254 	struct cxl_nvdimm_bridge *cxl_nvb = _cxl_nvb;
255 	struct nvdimm_bus *nvdimm_bus = cxl_nvb->nvdimm_bus;
256 
257 	bus_for_each_dev(&cxl_bus_type, NULL, cxl_nvb, detach_nvdimm);
258 
259 	cxl_nvb->nvdimm_bus = NULL;
260 	nvdimm_bus_unregister(nvdimm_bus);
261 }
262 
263 static int cxl_nvdimm_bridge_probe(struct device *dev)
264 {
265 	struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev);
266 
267 	cxl_nvb->nd_desc = (struct nvdimm_bus_descriptor) {
268 		.provider_name = "CXL",
269 		.module = THIS_MODULE,
270 		.ndctl = cxl_pmem_ctl,
271 	};
272 
273 	cxl_nvb->nvdimm_bus =
274 		nvdimm_bus_register(&cxl_nvb->dev, &cxl_nvb->nd_desc);
275 
276 	if (!cxl_nvb->nvdimm_bus)
277 		return -ENOMEM;
278 
279 	return devm_add_action_or_reset(dev, unregister_nvdimm_bus, cxl_nvb);
280 }
281 
282 static struct cxl_driver cxl_nvdimm_bridge_driver = {
283 	.name = "cxl_nvdimm_bridge",
284 	.probe = cxl_nvdimm_bridge_probe,
285 	.id = CXL_DEVICE_NVDIMM_BRIDGE,
286 	.drv = {
287 		.suppress_bind_attrs = true,
288 	},
289 };
290 
291 static void unregister_nvdimm_region(void *nd_region)
292 {
293 	nvdimm_region_delete(nd_region);
294 }
295 
296 static void cxlr_pmem_remove_resource(void *res)
297 {
298 	remove_resource(res);
299 }
300 
301 struct cxl_pmem_region_info {
302 	u64 offset;
303 	u64 serial;
304 };
305 
306 static int cxl_pmem_region_probe(struct device *dev)
307 {
308 	struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE];
309 	struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
310 	struct cxl_region *cxlr = cxlr_pmem->cxlr;
311 	struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
312 	struct cxl_pmem_region_info *info = NULL;
313 	struct nd_interleave_set *nd_set;
314 	struct nd_region_desc ndr_desc;
315 	struct cxl_nvdimm *cxl_nvd;
316 	struct nvdimm *nvdimm;
317 	struct resource *res;
318 	int rc, i = 0;
319 
320 	memset(&mappings, 0, sizeof(mappings));
321 	memset(&ndr_desc, 0, sizeof(ndr_desc));
322 
323 	res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL);
324 	if (!res)
325 		return -ENOMEM;
326 
327 	res->name = "Persistent Memory";
328 	res->start = cxlr_pmem->hpa_range.start;
329 	res->end = cxlr_pmem->hpa_range.end;
330 	res->flags = IORESOURCE_MEM;
331 	res->desc = IORES_DESC_PERSISTENT_MEMORY;
332 
333 	rc = insert_resource(&iomem_resource, res);
334 	if (rc)
335 		return rc;
336 
337 	rc = devm_add_action_or_reset(dev, cxlr_pmem_remove_resource, res);
338 	if (rc)
339 		return rc;
340 
341 	ndr_desc.res = res;
342 	ndr_desc.provider_data = cxlr_pmem;
343 
344 	ndr_desc.numa_node = memory_add_physaddr_to_nid(res->start);
345 	ndr_desc.target_node = phys_to_target_node(res->start);
346 	if (ndr_desc.target_node == NUMA_NO_NODE) {
347 		ndr_desc.target_node = ndr_desc.numa_node;
348 		dev_dbg(&cxlr->dev, "changing target node from %d to %d",
349 			NUMA_NO_NODE, ndr_desc.target_node);
350 	}
351 
352 	nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
353 	if (!nd_set)
354 		return -ENOMEM;
355 
356 	ndr_desc.memregion = cxlr->id;
357 	set_bit(ND_REGION_CXL, &ndr_desc.flags);
358 	set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
359 
360 	info = kmalloc_array(cxlr_pmem->nr_mappings, sizeof(*info), GFP_KERNEL);
361 	if (!info)
362 		return -ENOMEM;
363 
364 	for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
365 		struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
366 		struct cxl_memdev *cxlmd = m->cxlmd;
367 		struct cxl_dev_state *cxlds = cxlmd->cxlds;
368 
369 		cxl_nvd = cxlmd->cxl_nvd;
370 		nvdimm = dev_get_drvdata(&cxl_nvd->dev);
371 		if (!nvdimm) {
372 			dev_dbg(dev, "[%d]: %s: no nvdimm found\n", i,
373 				dev_name(&cxlmd->dev));
374 			rc = -ENODEV;
375 			goto out_nvd;
376 		}
377 
378 		m->cxl_nvd = cxl_nvd;
379 		mappings[i] = (struct nd_mapping_desc) {
380 			.nvdimm = nvdimm,
381 			.start = m->start,
382 			.size = m->size,
383 			.position = i,
384 		};
385 		info[i].offset = m->start;
386 		info[i].serial = cxlds->serial;
387 	}
388 	ndr_desc.num_mappings = cxlr_pmem->nr_mappings;
389 	ndr_desc.mapping = mappings;
390 
391 	/*
392 	 * TODO enable CXL labels which skip the need for 'interleave-set cookie'
393 	 */
394 	nd_set->cookie1 =
395 		nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0);
396 	nd_set->cookie2 = nd_set->cookie1;
397 	ndr_desc.nd_set = nd_set;
398 
399 	cxlr_pmem->nd_region =
400 		nvdimm_pmem_region_create(cxl_nvb->nvdimm_bus, &ndr_desc);
401 	if (!cxlr_pmem->nd_region) {
402 		rc = -ENOMEM;
403 		goto out_nvd;
404 	}
405 
406 	rc = devm_add_action_or_reset(dev, unregister_nvdimm_region,
407 				      cxlr_pmem->nd_region);
408 out_nvd:
409 	kfree(info);
410 
411 	return rc;
412 }
413 
414 static struct cxl_driver cxl_pmem_region_driver = {
415 	.name = "cxl_pmem_region",
416 	.probe = cxl_pmem_region_probe,
417 	.id = CXL_DEVICE_PMEM_REGION,
418 	.drv = {
419 		.suppress_bind_attrs = true,
420 	},
421 };
422 
423 static __init int cxl_pmem_init(void)
424 {
425 	int rc;
426 
427 	set_bit(CXL_MEM_COMMAND_ID_SET_SHUTDOWN_STATE, exclusive_cmds);
428 	set_bit(CXL_MEM_COMMAND_ID_SET_LSA, exclusive_cmds);
429 
430 	rc = cxl_driver_register(&cxl_nvdimm_bridge_driver);
431 	if (rc)
432 		return rc;
433 
434 	rc = cxl_driver_register(&cxl_nvdimm_driver);
435 	if (rc)
436 		goto err_nvdimm;
437 
438 	rc = cxl_driver_register(&cxl_pmem_region_driver);
439 	if (rc)
440 		goto err_region;
441 
442 	return 0;
443 
444 err_region:
445 	cxl_driver_unregister(&cxl_nvdimm_driver);
446 err_nvdimm:
447 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
448 	return rc;
449 }
450 
451 static __exit void cxl_pmem_exit(void)
452 {
453 	cxl_driver_unregister(&cxl_pmem_region_driver);
454 	cxl_driver_unregister(&cxl_nvdimm_driver);
455 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
456 }
457 
458 MODULE_DESCRIPTION("CXL PMEM: Persistent Memory Support");
459 MODULE_LICENSE("GPL v2");
460 module_init(cxl_pmem_init);
461 module_exit(cxl_pmem_exit);
462 MODULE_IMPORT_NS(CXL);
463 MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM_BRIDGE);
464 MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM);
465 MODULE_ALIAS_CXL(CXL_DEVICE_PMEM_REGION);
466