xref: /linux/arch/s390/pci/pci_clp.c (revision f90f2145b2804c0166126a6c8fbf51d695917df3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright IBM Corp. 2012
4  *
5  * Author(s):
6  *   Jan Glauber <jang@linux.vnet.ibm.com>
7  */
8 
9 #define KMSG_COMPONENT "zpci"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11 
12 #include <linux/compat.h>
13 #include <linux/kernel.h>
14 #include <linux/miscdevice.h>
15 #include <linux/slab.h>
16 #include <linux/err.h>
17 #include <linux/delay.h>
18 #include <linux/pci.h>
19 #include <linux/uaccess.h>
20 #include <asm/asm-extable.h>
21 #include <asm/pci_debug.h>
22 #include <asm/pci_clp.h>
23 #include <asm/asm.h>
24 #include <asm/clp.h>
25 #include <uapi/asm/clp.h>
26 
27 #include "pci_bus.h"
28 
29 bool zpci_unique_uid;
30 
31 void update_uid_checking(bool new)
32 {
33 	if (zpci_unique_uid != new)
34 		zpci_dbg(3, "uid checking:%d\n", new);
35 
36 	zpci_unique_uid = new;
37 }
38 
39 static inline void zpci_err_clp(unsigned int rsp, int rc)
40 {
41 	struct {
42 		unsigned int rsp;
43 		int rc;
44 	} __packed data = {rsp, rc};
45 
46 	zpci_err_hex(&data, sizeof(data));
47 }
48 
49 /*
50  * Call Logical Processor with c=1, lps=0 and command 1
51  * to get the bit mask of installed logical processors
52  */
53 static inline int clp_get_ilp(unsigned long *ilp)
54 {
55 	unsigned long mask;
56 	int cc, exception;
57 
58 	exception = 1;
59 	asm_inline volatile (
60 		"	.insn	rrf,0xb9a00000,%[mask],%[cmd],8,0\n"
61 		"0:	lhi	%[exc],0\n"
62 		"1:\n"
63 		CC_IPM(cc)
64 		EX_TABLE(0b, 1b)
65 		: CC_OUT(cc, cc), [mask] "=d" (mask), [exc] "+d" (exception)
66 		: [cmd] "a" (1)
67 		: CC_CLOBBER);
68 	*ilp = mask;
69 	return exception ? 3 : CC_TRANSFORM(cc);
70 }
71 
72 /*
73  * Call Logical Processor with c=0, the give constant lps and an lpcb request.
74  */
75 static __always_inline int clp_req(void *data, unsigned int lps)
76 {
77 	struct { u8 _[CLP_BLK_SIZE]; } *req = data;
78 	int cc, exception;
79 	u64 ignored;
80 
81 	exception = 1;
82 	asm_inline volatile (
83 		"	.insn	rrf,0xb9a00000,%[ign],%[req],0,%[lps]\n"
84 		"0:	lhi	%[exc],0\n"
85 		"1:\n"
86 		CC_IPM(cc)
87 		EX_TABLE(0b, 1b)
88 		: CC_OUT(cc, cc), [ign] "=d" (ignored), "+m" (*req), [exc] "+d" (exception)
89 		: [req] "a" (req), [lps] "i" (lps)
90 		: CC_CLOBBER);
91 	return exception ? 3 : CC_TRANSFORM(cc);
92 }
93 
94 static void *clp_alloc_block(gfp_t gfp_mask)
95 {
96 	return (void *) __get_free_pages(gfp_mask, get_order(CLP_BLK_SIZE));
97 }
98 
99 static void clp_free_block(void *ptr)
100 {
101 	free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
102 }
103 
104 static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
105 				      struct clp_rsp_query_pci_grp *response)
106 {
107 	zdev->tlb_refresh = response->refresh;
108 	zdev->dma_mask = response->dasm;
109 	zdev->msi_addr = response->msia;
110 	zdev->max_msi = response->noi;
111 	zdev->fmb_update = response->mui;
112 	zdev->version = response->version;
113 	zdev->maxstbl = response->maxstbl;
114 	zdev->dtsm = response->dtsm;
115 	zdev->rtr_avail = response->rtr;
116 
117 	switch (response->version) {
118 	case 1:
119 		zdev->max_bus_speed = PCIE_SPEED_5_0GT;
120 		break;
121 	default:
122 		zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
123 		break;
124 	}
125 }
126 
127 static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
128 {
129 	struct clp_req_rsp_query_pci_grp *rrb;
130 	int rc;
131 
132 	rrb = clp_alloc_block(GFP_KERNEL);
133 	if (!rrb)
134 		return -ENOMEM;
135 
136 	memset(rrb, 0, sizeof(*rrb));
137 	rrb->request.hdr.len = sizeof(rrb->request);
138 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
139 	rrb->response.hdr.len = sizeof(rrb->response);
140 	rrb->request.pfgid = pfgid;
141 
142 	rc = clp_req(rrb, CLP_LPS_PCI);
143 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
144 		clp_store_query_pci_fngrp(zdev, &rrb->response);
145 	else {
146 		zpci_err("Q PCI FGRP:\n");
147 		zpci_err_clp(rrb->response.hdr.rsp, rc);
148 		rc = -EIO;
149 	}
150 	clp_free_block(rrb);
151 	return rc;
152 }
153 
154 static int clp_store_query_pci_fn(struct zpci_dev *zdev,
155 				  struct clp_rsp_query_pci *response)
156 {
157 	int i;
158 
159 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
160 		zdev->bars[i].val = le32_to_cpu(response->bar[i]);
161 		zdev->bars[i].size = response->bar_size[i];
162 	}
163 	zdev->start_dma = response->sdma;
164 	zdev->end_dma = response->edma;
165 	zdev->pchid = response->pchid;
166 	zdev->pfgid = response->pfgid;
167 	zdev->pft = response->pft;
168 	zdev->vfn = response->vfn;
169 	zdev->port = response->port;
170 	zdev->fidparm = response->fidparm;
171 	zdev->uid = response->uid;
172 	zdev->fmb_length = sizeof(u32) * response->fmb_len;
173 	zdev->is_physfn = response->is_physfn;
174 	zdev->rid_available = response->rid_avail;
175 	if (zdev->rid_available)
176 		zdev->rid = response->rid;
177 	zdev->tid_avail = response->tid_avail;
178 	if (zdev->tid_avail)
179 		zdev->tid = response->tid;
180 
181 	memcpy(zdev->pfip, response->pfip, sizeof(zdev->pfip));
182 	if (response->util_str_avail) {
183 		memcpy(zdev->util_str, response->util_str,
184 		       sizeof(zdev->util_str));
185 		zdev->util_str_avail = 1;
186 	}
187 	zdev->mio_capable = response->mio_addr_avail;
188 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
189 		if (!(response->mio.valid & (1 << (PCI_STD_NUM_BARS - i - 1))))
190 			continue;
191 
192 		zdev->bars[i].mio_wb = (void __iomem *) response->mio.addr[i].wb;
193 		zdev->bars[i].mio_wt = (void __iomem *) response->mio.addr[i].wt;
194 	}
195 	return 0;
196 }
197 
198 int clp_query_pci_fn(struct zpci_dev *zdev)
199 {
200 	struct clp_req_rsp_query_pci *rrb;
201 	int rc;
202 
203 	rrb = clp_alloc_block(GFP_KERNEL);
204 	if (!rrb)
205 		return -ENOMEM;
206 
207 	memset(rrb, 0, sizeof(*rrb));
208 	rrb->request.hdr.len = sizeof(rrb->request);
209 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
210 	rrb->response.hdr.len = sizeof(rrb->response);
211 	rrb->request.fh = zdev->fh;
212 
213 	rc = clp_req(rrb, CLP_LPS_PCI);
214 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
215 		rc = clp_store_query_pci_fn(zdev, &rrb->response);
216 		if (rc)
217 			goto out;
218 		rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
219 	} else {
220 		zpci_err("Q PCI FN:\n");
221 		zpci_err_clp(rrb->response.hdr.rsp, rc);
222 		rc = -EIO;
223 	}
224 out:
225 	clp_free_block(rrb);
226 	return rc;
227 }
228 
229 /**
230  * clp_set_pci_fn() - Execute a command on a PCI function
231  * @zdev: Function that will be affected
232  * @fh: Out parameter for updated function handle
233  * @nr_dma_as: DMA address space number
234  * @command: The command code to execute
235  *
236  * Returns: 0 on success, < 0 for Linux errors (e.g. -ENOMEM), and
237  * > 0 for non-success platform responses
238  */
239 static int clp_set_pci_fn(struct zpci_dev *zdev, u32 *fh, u8 nr_dma_as, u8 command)
240 {
241 	struct clp_req_rsp_set_pci *rrb;
242 	int rc, retries = 100;
243 	u32 gisa = 0;
244 
245 	*fh = 0;
246 	rrb = clp_alloc_block(GFP_KERNEL);
247 	if (!rrb)
248 		return -ENOMEM;
249 
250 	if (command != CLP_SET_DISABLE_PCI_FN)
251 		gisa = zdev->gisa;
252 
253 	do {
254 		memset(rrb, 0, sizeof(*rrb));
255 		rrb->request.hdr.len = sizeof(rrb->request);
256 		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
257 		rrb->response.hdr.len = sizeof(rrb->response);
258 		rrb->request.fh = zdev->fh;
259 		rrb->request.oc = command;
260 		rrb->request.ndas = nr_dma_as;
261 		rrb->request.gisa = gisa;
262 
263 		rc = clp_req(rrb, CLP_LPS_PCI);
264 		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
265 			retries--;
266 			if (retries < 0)
267 				break;
268 			msleep(20);
269 		}
270 	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
271 
272 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
273 		*fh = rrb->response.fh;
274 	} else {
275 		zpci_err("Set PCI FN:\n");
276 		zpci_err_clp(rrb->response.hdr.rsp, rc);
277 		if (!rc)
278 			rc = rrb->response.hdr.rsp;
279 	}
280 	clp_free_block(rrb);
281 	return rc;
282 }
283 
284 int clp_setup_writeback_mio(void)
285 {
286 	struct clp_req_rsp_slpc_pci *rrb;
287 	u8  wb_bit_pos;
288 	int rc;
289 
290 	rrb = clp_alloc_block(GFP_KERNEL);
291 	if (!rrb)
292 		return -ENOMEM;
293 
294 	memset(rrb, 0, sizeof(*rrb));
295 	rrb->request.hdr.len = sizeof(rrb->request);
296 	rrb->request.hdr.cmd = CLP_SLPC;
297 	rrb->response.hdr.len = sizeof(rrb->response);
298 
299 	rc = clp_req(rrb, CLP_LPS_PCI);
300 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
301 		if (rrb->response.vwb) {
302 			wb_bit_pos = rrb->response.mio_wb;
303 			set_bit_inv(wb_bit_pos, &mio_wb_bit_mask);
304 			zpci_dbg(3, "wb bit: %d\n", wb_bit_pos);
305 		} else {
306 			zpci_dbg(3, "wb bit: n.a.\n");
307 		}
308 
309 	} else {
310 		zpci_err("SLPC PCI:\n");
311 		zpci_err_clp(rrb->response.hdr.rsp, rc);
312 		rc = -EIO;
313 	}
314 	clp_free_block(rrb);
315 	return rc;
316 }
317 
318 int clp_enable_fh(struct zpci_dev *zdev, u32 *fh, u8 nr_dma_as)
319 {
320 	int rc;
321 
322 	rc = clp_set_pci_fn(zdev, fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
323 	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, *fh, rc);
324 	if (!rc && zpci_use_mio(zdev)) {
325 		rc = clp_set_pci_fn(zdev, fh, nr_dma_as, CLP_SET_ENABLE_MIO);
326 		zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n",
327 				zdev->fid, *fh, rc);
328 		if (rc)
329 			clp_disable_fh(zdev, fh);
330 	}
331 	return rc;
332 }
333 
334 int clp_disable_fh(struct zpci_dev *zdev, u32 *fh)
335 {
336 	int rc;
337 
338 	if (!zdev_enabled(zdev))
339 		return 0;
340 
341 	rc = clp_set_pci_fn(zdev, fh, 0, CLP_SET_DISABLE_PCI_FN);
342 	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, *fh, rc);
343 	return rc;
344 }
345 
346 static int clp_list_pci_req(struct clp_req_rsp_list_pci *rrb,
347 			    u64 *resume_token, int *nentries)
348 {
349 	int rc;
350 
351 	memset(rrb, 0, sizeof(*rrb));
352 	rrb->request.hdr.len = sizeof(rrb->request);
353 	rrb->request.hdr.cmd = CLP_LIST_PCI;
354 	/* store as many entries as possible */
355 	rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
356 	rrb->request.resume_token = *resume_token;
357 
358 	/* Get PCI function handle list */
359 	rc = clp_req(rrb, CLP_LPS_PCI);
360 	if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
361 		zpci_err("List PCI FN:\n");
362 		zpci_err_clp(rrb->response.hdr.rsp, rc);
363 		return -EIO;
364 	}
365 
366 	update_uid_checking(rrb->response.uid_checking);
367 	WARN_ON_ONCE(rrb->response.entry_size !=
368 		sizeof(struct clp_fh_list_entry));
369 
370 	*nentries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
371 		rrb->response.entry_size;
372 	*resume_token = rrb->response.resume_token;
373 
374 	return rc;
375 }
376 
377 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb, void *data,
378 			void (*cb)(struct clp_fh_list_entry *, void *))
379 {
380 	u64 resume_token = 0;
381 	int nentries, i, rc;
382 
383 	do {
384 		rc = clp_list_pci_req(rrb, &resume_token, &nentries);
385 		if (rc)
386 			return rc;
387 		for (i = 0; i < nentries; i++)
388 			cb(&rrb->response.fh_list[i], data);
389 	} while (resume_token);
390 
391 	return rc;
392 }
393 
394 static int clp_find_pci(struct clp_req_rsp_list_pci *rrb, u32 fid,
395 			struct clp_fh_list_entry *entry)
396 {
397 	struct clp_fh_list_entry *fh_list;
398 	u64 resume_token = 0;
399 	int nentries, i, rc;
400 
401 	do {
402 		rc = clp_list_pci_req(rrb, &resume_token, &nentries);
403 		if (rc)
404 			return rc;
405 		fh_list = rrb->response.fh_list;
406 		for (i = 0; i < nentries; i++) {
407 			if (fh_list[i].fid == fid) {
408 				*entry = fh_list[i];
409 				return 0;
410 			}
411 		}
412 	} while (resume_token);
413 
414 	return -ENODEV;
415 }
416 
417 static void __clp_add(struct clp_fh_list_entry *entry, void *data)
418 {
419 	struct list_head *scan_list = data;
420 	struct zpci_dev *zdev;
421 
422 	if (!entry->vendor_id)
423 		return;
424 
425 	zdev = get_zdev_by_fid(entry->fid);
426 	if (zdev) {
427 		zpci_zdev_put(zdev);
428 		return;
429 	}
430 	zdev = zpci_create_device(entry->fid, entry->fh, entry->config_state);
431 	list_add_tail(&zdev->entry, scan_list);
432 }
433 
434 int clp_scan_pci_devices(struct list_head *scan_list)
435 {
436 	struct clp_req_rsp_list_pci *rrb;
437 	int rc;
438 
439 	rrb = clp_alloc_block(GFP_KERNEL);
440 	if (!rrb)
441 		return -ENOMEM;
442 
443 	rc = clp_list_pci(rrb, scan_list, __clp_add);
444 
445 	clp_free_block(rrb);
446 	return rc;
447 }
448 
449 /*
450  * Get the current function handle of the function matching @fid
451  */
452 int clp_refresh_fh(u32 fid, u32 *fh)
453 {
454 	struct clp_req_rsp_list_pci *rrb;
455 	struct clp_fh_list_entry entry;
456 	int rc;
457 
458 	rrb = clp_alloc_block(GFP_NOWAIT);
459 	if (!rrb)
460 		return -ENOMEM;
461 
462 	rc = clp_find_pci(rrb, fid, &entry);
463 	if (!rc)
464 		*fh = entry.fh;
465 
466 	clp_free_block(rrb);
467 	return rc;
468 }
469 
470 int clp_get_state(u32 fid, enum zpci_state *state)
471 {
472 	struct clp_req_rsp_list_pci *rrb;
473 	struct clp_fh_list_entry entry;
474 	int rc;
475 
476 	rrb = clp_alloc_block(GFP_ATOMIC);
477 	if (!rrb)
478 		return -ENOMEM;
479 
480 	rc = clp_find_pci(rrb, fid, &entry);
481 	if (!rc) {
482 		*state = entry.config_state;
483 	} else if (rc == -ENODEV) {
484 		*state = ZPCI_FN_STATE_RESERVED;
485 		rc = 0;
486 	}
487 
488 	clp_free_block(rrb);
489 	return rc;
490 }
491 
492 static int clp_base_slpc(struct clp_req *req, struct clp_req_rsp_slpc *lpcb)
493 {
494 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
495 
496 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
497 	    lpcb->response.hdr.len > limit)
498 		return -EINVAL;
499 	return clp_req(lpcb, CLP_LPS_BASE) ? -EOPNOTSUPP : 0;
500 }
501 
502 static int clp_base_command(struct clp_req *req, struct clp_req_hdr *lpcb)
503 {
504 	switch (lpcb->cmd) {
505 	case 0x0001: /* store logical-processor characteristics */
506 		return clp_base_slpc(req, (void *) lpcb);
507 	default:
508 		return -EINVAL;
509 	}
510 }
511 
512 static int clp_pci_slpc(struct clp_req *req, struct clp_req_rsp_slpc_pci *lpcb)
513 {
514 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
515 
516 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
517 	    lpcb->response.hdr.len > limit)
518 		return -EINVAL;
519 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
520 }
521 
522 static int clp_pci_list(struct clp_req *req, struct clp_req_rsp_list_pci *lpcb)
523 {
524 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
525 
526 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
527 	    lpcb->response.hdr.len > limit)
528 		return -EINVAL;
529 	if (lpcb->request.reserved2 != 0)
530 		return -EINVAL;
531 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
532 }
533 
534 static int clp_pci_query(struct clp_req *req,
535 			 struct clp_req_rsp_query_pci *lpcb)
536 {
537 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
538 
539 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
540 	    lpcb->response.hdr.len > limit)
541 		return -EINVAL;
542 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0)
543 		return -EINVAL;
544 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
545 }
546 
547 static int clp_pci_query_grp(struct clp_req *req,
548 			     struct clp_req_rsp_query_pci_grp *lpcb)
549 {
550 	unsigned long limit = PAGE_SIZE - sizeof(lpcb->request);
551 
552 	if (lpcb->request.hdr.len != sizeof(lpcb->request) ||
553 	    lpcb->response.hdr.len > limit)
554 		return -EINVAL;
555 	if (lpcb->request.reserved2 != 0 || lpcb->request.reserved3 != 0 ||
556 	    lpcb->request.reserved4 != 0)
557 		return -EINVAL;
558 	return clp_req(lpcb, CLP_LPS_PCI) ? -EOPNOTSUPP : 0;
559 }
560 
561 static int clp_pci_command(struct clp_req *req, struct clp_req_hdr *lpcb)
562 {
563 	switch (lpcb->cmd) {
564 	case 0x0001: /* store logical-processor characteristics */
565 		return clp_pci_slpc(req, (void *) lpcb);
566 	case 0x0002: /* list PCI functions */
567 		return clp_pci_list(req, (void *) lpcb);
568 	case 0x0003: /* query PCI function */
569 		return clp_pci_query(req, (void *) lpcb);
570 	case 0x0004: /* query PCI function group */
571 		return clp_pci_query_grp(req, (void *) lpcb);
572 	default:
573 		return -EINVAL;
574 	}
575 }
576 
577 static int clp_normal_command(struct clp_req *req)
578 {
579 	struct clp_req_hdr *lpcb;
580 	void __user *uptr;
581 	int rc;
582 
583 	rc = -EINVAL;
584 	if (req->lps != 0 && req->lps != 2)
585 		goto out;
586 
587 	rc = -ENOMEM;
588 	lpcb = clp_alloc_block(GFP_KERNEL);
589 	if (!lpcb)
590 		goto out;
591 
592 	rc = -EFAULT;
593 	uptr = (void __force __user *)(unsigned long) req->data_p;
594 	if (copy_from_user(lpcb, uptr, PAGE_SIZE) != 0)
595 		goto out_free;
596 
597 	rc = -EINVAL;
598 	if (lpcb->fmt != 0 || lpcb->reserved1 != 0 || lpcb->reserved2 != 0)
599 		goto out_free;
600 
601 	switch (req->lps) {
602 	case 0:
603 		rc = clp_base_command(req, lpcb);
604 		break;
605 	case 2:
606 		rc = clp_pci_command(req, lpcb);
607 		break;
608 	}
609 	if (rc)
610 		goto out_free;
611 
612 	rc = -EFAULT;
613 	if (copy_to_user(uptr, lpcb, PAGE_SIZE) != 0)
614 		goto out_free;
615 
616 	rc = 0;
617 
618 out_free:
619 	clp_free_block(lpcb);
620 out:
621 	return rc;
622 }
623 
624 static int clp_immediate_command(struct clp_req *req)
625 {
626 	void __user *uptr;
627 	unsigned long ilp;
628 	int exists;
629 
630 	if (req->cmd > 1 || clp_get_ilp(&ilp) != 0)
631 		return -EINVAL;
632 
633 	uptr = (void __force __user *)(unsigned long) req->data_p;
634 	if (req->cmd == 0) {
635 		/* Command code 0: test for a specific processor */
636 		exists = test_bit_inv(req->lps, &ilp);
637 		return put_user(exists, (int __user *) uptr);
638 	}
639 	/* Command code 1: return bit mask of installed processors */
640 	return put_user(ilp, (unsigned long __user *) uptr);
641 }
642 
643 static long clp_misc_ioctl(struct file *filp, unsigned int cmd,
644 			   unsigned long arg)
645 {
646 	struct clp_req req;
647 	void __user *argp;
648 
649 	if (cmd != CLP_SYNC)
650 		return -EINVAL;
651 
652 	argp = is_compat_task() ? compat_ptr(arg) : (void __user *) arg;
653 	if (copy_from_user(&req, argp, sizeof(req)))
654 		return -EFAULT;
655 	if (req.r != 0)
656 		return -EINVAL;
657 	return req.c ? clp_immediate_command(&req) : clp_normal_command(&req);
658 }
659 
660 static int clp_misc_release(struct inode *inode, struct file *filp)
661 {
662 	return 0;
663 }
664 
665 static const struct file_operations clp_misc_fops = {
666 	.owner = THIS_MODULE,
667 	.open = nonseekable_open,
668 	.release = clp_misc_release,
669 	.unlocked_ioctl = clp_misc_ioctl,
670 	.compat_ioctl = clp_misc_ioctl,
671 };
672 
673 static struct miscdevice clp_misc_device = {
674 	.minor = MISC_DYNAMIC_MINOR,
675 	.name = "clp",
676 	.fops = &clp_misc_fops,
677 };
678 
679 builtin_misc_device(clp_misc_device);
680