1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * IBM Accelerator Family 'GenWQE'
4 *
5 * (C) Copyright IBM Corp. 2013
6 *
7 * Author: Frank Haverkamp <haver@linux.vnet.ibm.com>
8 * Author: Joerg-Stephan Vogt <jsvogt@de.ibm.com>
9 * Author: Michael Jung <mijung@gmx.net>
10 * Author: Michael Ruettger <michael@ibmra.de>
11 */
12
13/*
14 * Character device representation of the GenWQE device. This allows
15 * user-space applications to communicate with the card.
16 */
17
18#include <linux/kernel.h>
19#include <linux/types.h>
20#include <linux/module.h>
21#include <linux/pci.h>
22#include <linux/string.h>
23#include <linux/fs.h>
24#include <linux/sched/signal.h>
25#include <linux/wait.h>
26#include <linux/delay.h>
27#include <linux/atomic.h>
28
29#include "card_base.h"
30#include "card_ddcb.h"
31
32static int genwqe_open_files(struct genwqe_dev *cd)
33{
34 int rc;
35 unsigned long flags;
36
37 spin_lock_irqsave(&cd->file_lock, flags);
38 rc = list_empty(head: &cd->file_list);
39 spin_unlock_irqrestore(lock: &cd->file_lock, flags);
40 return !rc;
41}
42
43static void genwqe_add_file(struct genwqe_dev *cd, struct genwqe_file *cfile)
44{
45 unsigned long flags;
46
47 cfile->opener = get_pid(pid: task_tgid(current));
48 spin_lock_irqsave(&cd->file_lock, flags);
49 list_add(new: &cfile->list, head: &cd->file_list);
50 spin_unlock_irqrestore(lock: &cd->file_lock, flags);
51}
52
53static int genwqe_del_file(struct genwqe_dev *cd, struct genwqe_file *cfile)
54{
55 unsigned long flags;
56
57 spin_lock_irqsave(&cd->file_lock, flags);
58 list_del(entry: &cfile->list);
59 spin_unlock_irqrestore(lock: &cd->file_lock, flags);
60 put_pid(pid: cfile->opener);
61
62 return 0;
63}
64
65static void genwqe_add_pin(struct genwqe_file *cfile, struct dma_mapping *m)
66{
67 unsigned long flags;
68
69 spin_lock_irqsave(&cfile->pin_lock, flags);
70 list_add(new: &m->pin_list, head: &cfile->pin_list);
71 spin_unlock_irqrestore(lock: &cfile->pin_lock, flags);
72}
73
74static int genwqe_del_pin(struct genwqe_file *cfile, struct dma_mapping *m)
75{
76 unsigned long flags;
77
78 spin_lock_irqsave(&cfile->pin_lock, flags);
79 list_del(entry: &m->pin_list);
80 spin_unlock_irqrestore(lock: &cfile->pin_lock, flags);
81
82 return 0;
83}
84
85/**
86 * genwqe_search_pin() - Search for the mapping for a userspace address
87 * @cfile: Descriptor of opened file
88 * @u_addr: User virtual address
89 * @size: Size of buffer
90 * @virt_addr: Virtual address to be updated
91 *
92 * Return: Pointer to the corresponding mapping NULL if not found
93 */
94static struct dma_mapping *genwqe_search_pin(struct genwqe_file *cfile,
95 unsigned long u_addr,
96 unsigned int size,
97 void **virt_addr)
98{
99 unsigned long flags;
100 struct dma_mapping *m;
101
102 spin_lock_irqsave(&cfile->pin_lock, flags);
103
104 list_for_each_entry(m, &cfile->pin_list, pin_list) {
105 if ((((u64)m->u_vaddr) <= (u_addr)) &&
106 (((u64)m->u_vaddr + m->size) >= (u_addr + size))) {
107
108 if (virt_addr)
109 *virt_addr = m->k_vaddr +
110 (u_addr - (u64)m->u_vaddr);
111
112 spin_unlock_irqrestore(lock: &cfile->pin_lock, flags);
113 return m;
114 }
115 }
116 spin_unlock_irqrestore(lock: &cfile->pin_lock, flags);
117 return NULL;
118}
119
120static void __genwqe_add_mapping(struct genwqe_file *cfile,
121 struct dma_mapping *dma_map)
122{
123 unsigned long flags;
124
125 spin_lock_irqsave(&cfile->map_lock, flags);
126 list_add(new: &dma_map->card_list, head: &cfile->map_list);
127 spin_unlock_irqrestore(lock: &cfile->map_lock, flags);
128}
129
130static void __genwqe_del_mapping(struct genwqe_file *cfile,
131 struct dma_mapping *dma_map)
132{
133 unsigned long flags;
134
135 spin_lock_irqsave(&cfile->map_lock, flags);
136 list_del(entry: &dma_map->card_list);
137 spin_unlock_irqrestore(lock: &cfile->map_lock, flags);
138}
139
140
141/**
142 * __genwqe_search_mapping() - Search for the mapping for a userspace address
143 * @cfile: descriptor of opened file
144 * @u_addr: user virtual address
145 * @size: size of buffer
146 * @dma_addr: DMA address to be updated
147 * @virt_addr: Virtual address to be updated
148 * Return: Pointer to the corresponding mapping NULL if not found
149 */
150static struct dma_mapping *__genwqe_search_mapping(struct genwqe_file *cfile,
151 unsigned long u_addr,
152 unsigned int size,
153 dma_addr_t *dma_addr,
154 void **virt_addr)
155{
156 unsigned long flags;
157 struct dma_mapping *m;
158 struct pci_dev *pci_dev = cfile->cd->pci_dev;
159
160 spin_lock_irqsave(&cfile->map_lock, flags);
161 list_for_each_entry(m, &cfile->map_list, card_list) {
162
163 if ((((u64)m->u_vaddr) <= (u_addr)) &&
164 (((u64)m->u_vaddr + m->size) >= (u_addr + size))) {
165
166 /* match found: current is as expected and
167 addr is in range */
168 if (dma_addr)
169 *dma_addr = m->dma_addr +
170 (u_addr - (u64)m->u_vaddr);
171
172 if (virt_addr)
173 *virt_addr = m->k_vaddr +
174 (u_addr - (u64)m->u_vaddr);
175
176 spin_unlock_irqrestore(lock: &cfile->map_lock, flags);
177 return m;
178 }
179 }
180 spin_unlock_irqrestore(lock: &cfile->map_lock, flags);
181
182 dev_err(&pci_dev->dev,
183 "[%s] Entry not found: u_addr=%lx, size=%x\n",
184 __func__, u_addr, size);
185
186 return NULL;
187}
188
189static void genwqe_remove_mappings(struct genwqe_file *cfile)
190{
191 int i = 0;
192 struct list_head *node, *next;
193 struct dma_mapping *dma_map;
194 struct genwqe_dev *cd = cfile->cd;
195 struct pci_dev *pci_dev = cfile->cd->pci_dev;
196
197 list_for_each_safe(node, next, &cfile->map_list) {
198 dma_map = list_entry(node, struct dma_mapping, card_list);
199
200 list_del_init(entry: &dma_map->card_list);
201
202 /*
203 * This is really a bug, because those things should
204 * have been already tidied up.
205 *
206 * GENWQE_MAPPING_RAW should have been removed via mmunmap().
207 * GENWQE_MAPPING_SGL_TEMP should be removed by tidy up code.
208 */
209 dev_err(&pci_dev->dev,
210 "[%s] %d. cleanup mapping: u_vaddr=%p u_kaddr=%016lx dma_addr=%lx\n",
211 __func__, i++, dma_map->u_vaddr,
212 (unsigned long)dma_map->k_vaddr,
213 (unsigned long)dma_map->dma_addr);
214
215 if (dma_map->type == GENWQE_MAPPING_RAW) {
216 /* we allocated this dynamically */
217 __genwqe_free_consistent(cd, size: dma_map->size,
218 vaddr: dma_map->k_vaddr,
219 dma_handle: dma_map->dma_addr);
220 kfree(objp: dma_map);
221 } else if (dma_map->type == GENWQE_MAPPING_SGL_TEMP) {
222 /* we use dma_map statically from the request */
223 genwqe_user_vunmap(cd, m: dma_map);
224 }
225 }
226}
227
228static void genwqe_remove_pinnings(struct genwqe_file *cfile)
229{
230 struct list_head *node, *next;
231 struct dma_mapping *dma_map;
232 struct genwqe_dev *cd = cfile->cd;
233
234 list_for_each_safe(node, next, &cfile->pin_list) {
235 dma_map = list_entry(node, struct dma_mapping, pin_list);
236
237 /*
238 * This is not a bug, because a killed processed might
239 * not call the unpin ioctl, which is supposed to free
240 * the resources.
241 *
242 * Pinnings are dymically allocated and need to be
243 * deleted.
244 */
245 list_del_init(entry: &dma_map->pin_list);
246 genwqe_user_vunmap(cd, m: dma_map);
247 kfree(objp: dma_map);
248 }
249}
250
251/**
252 * genwqe_kill_fasync() - Send signal to all processes with open GenWQE files
253 * @cd: GenWQE device information
254 * @sig: Signal to send out
255 *
256 * E.g. genwqe_send_signal(cd, SIGIO);
257 */
258static int genwqe_kill_fasync(struct genwqe_dev *cd, int sig)
259{
260 unsigned int files = 0;
261 unsigned long flags;
262 struct genwqe_file *cfile;
263
264 spin_lock_irqsave(&cd->file_lock, flags);
265 list_for_each_entry(cfile, &cd->file_list, list) {
266 if (cfile->async_queue)
267 kill_fasync(&cfile->async_queue, sig, POLL_HUP);
268 files++;
269 }
270 spin_unlock_irqrestore(lock: &cd->file_lock, flags);
271 return files;
272}
273
274static int genwqe_terminate(struct genwqe_dev *cd)
275{
276 unsigned int files = 0;
277 unsigned long flags;
278 struct genwqe_file *cfile;
279
280 spin_lock_irqsave(&cd->file_lock, flags);
281 list_for_each_entry(cfile, &cd->file_list, list) {
282 kill_pid(pid: cfile->opener, SIGKILL, priv: 1);
283 files++;
284 }
285 spin_unlock_irqrestore(lock: &cd->file_lock, flags);
286 return files;
287}
288
289/**
290 * genwqe_open() - file open
291 * @inode: file system information
292 * @filp: file handle
293 *
294 * This function is executed whenever an application calls
295 * open("/dev/genwqe",..).
296 *
297 * Return: 0 if successful or <0 if errors
298 */
299static int genwqe_open(struct inode *inode, struct file *filp)
300{
301 struct genwqe_dev *cd;
302 struct genwqe_file *cfile;
303
304 cfile = kzalloc(size: sizeof(*cfile), GFP_KERNEL);
305 if (cfile == NULL)
306 return -ENOMEM;
307
308 cd = container_of(inode->i_cdev, struct genwqe_dev, cdev_genwqe);
309 cfile->cd = cd;
310 cfile->filp = filp;
311 cfile->client = NULL;
312
313 spin_lock_init(&cfile->map_lock); /* list of raw memory allocations */
314 INIT_LIST_HEAD(list: &cfile->map_list);
315
316 spin_lock_init(&cfile->pin_lock); /* list of user pinned memory */
317 INIT_LIST_HEAD(list: &cfile->pin_list);
318
319 filp->private_data = cfile;
320
321 genwqe_add_file(cd, cfile);
322 return 0;
323}
324
325/**
326 * genwqe_fasync() - Setup process to receive SIGIO.
327 * @fd: file descriptor
328 * @filp: file handle
329 * @mode: file mode
330 *
331 * Sending a signal is working as following:
332 *
333 * if (cdev->async_queue)
334 * kill_fasync(&cdev->async_queue, SIGIO, POLL_IN);
335 *
336 * Some devices also implement asynchronous notification to indicate
337 * when the device can be written; in this case, of course,
338 * kill_fasync must be called with a mode of POLL_OUT.
339 */
340static int genwqe_fasync(int fd, struct file *filp, int mode)
341{
342 struct genwqe_file *cdev = (struct genwqe_file *)filp->private_data;
343
344 return fasync_helper(fd, filp, mode, &cdev->async_queue);
345}
346
347
348/**
349 * genwqe_release() - file close
350 * @inode: file system information
351 * @filp: file handle
352 *
353 * This function is executed whenever an application calls 'close(fd_genwqe)'
354 *
355 * Return: always 0
356 */
357static int genwqe_release(struct inode *inode, struct file *filp)
358{
359 struct genwqe_file *cfile = (struct genwqe_file *)filp->private_data;
360 struct genwqe_dev *cd = cfile->cd;
361
362 /* there must be no entries in these lists! */
363 genwqe_remove_mappings(cfile);
364 genwqe_remove_pinnings(cfile);
365
366 /* remove this filp from the asynchronously notified filp's */
367 genwqe_fasync(fd: -1, filp, mode: 0);
368
369 /*
370 * For this to work we must not release cd when this cfile is
371 * not yet released, otherwise the list entry is invalid,
372 * because the list itself gets reinstantiated!
373 */
374 genwqe_del_file(cd, cfile);
375 kfree(objp: cfile);
376 return 0;
377}
378
379static void genwqe_vma_open(struct vm_area_struct *vma)
380{
381 /* nothing ... */
382}
383
384/**
385 * genwqe_vma_close() - Called each time when vma is unmapped
386 * @vma: VMA area to close
387 *
388 * Free memory which got allocated by GenWQE mmap().
389 */
390static void genwqe_vma_close(struct vm_area_struct *vma)
391{
392 unsigned long vsize = vma->vm_end - vma->vm_start;
393 struct inode *inode = file_inode(f: vma->vm_file);
394 struct dma_mapping *dma_map;
395 struct genwqe_dev *cd = container_of(inode->i_cdev, struct genwqe_dev,
396 cdev_genwqe);
397 struct pci_dev *pci_dev = cd->pci_dev;
398 dma_addr_t d_addr = 0;
399 struct genwqe_file *cfile = vma->vm_private_data;
400
401 dma_map = __genwqe_search_mapping(cfile, u_addr: vma->vm_start, size: vsize,
402 dma_addr: &d_addr, NULL);
403 if (dma_map == NULL) {
404 dev_err(&pci_dev->dev,
405 " [%s] err: mapping not found: v=%lx, p=%lx s=%lx\n",
406 __func__, vma->vm_start, vma->vm_pgoff << PAGE_SHIFT,
407 vsize);
408 return;
409 }
410 __genwqe_del_mapping(cfile, dma_map);
411 __genwqe_free_consistent(cd, size: dma_map->size, vaddr: dma_map->k_vaddr,
412 dma_handle: dma_map->dma_addr);
413 kfree(objp: dma_map);
414}
415
416static const struct vm_operations_struct genwqe_vma_ops = {
417 .open = genwqe_vma_open,
418 .close = genwqe_vma_close,
419};
420
421/**
422 * genwqe_mmap() - Provide contignous buffers to userspace
423 * @filp: File pointer (unused)
424 * @vma: VMA area to map
425 *
426 * We use mmap() to allocate contignous buffers used for DMA
427 * transfers. After the buffer is allocated we remap it to user-space
428 * and remember a reference to our dma_mapping data structure, where
429 * we store the associated DMA address and allocated size.
430 *
431 * When we receive a DDCB execution request with the ATS bits set to
432 * plain buffer, we lookup our dma_mapping list to find the
433 * corresponding DMA address for the associated user-space address.
434 */
435static int genwqe_mmap(struct file *filp, struct vm_area_struct *vma)
436{
437 int rc;
438 unsigned long pfn, vsize = vma->vm_end - vma->vm_start;
439 struct genwqe_file *cfile = (struct genwqe_file *)filp->private_data;
440 struct genwqe_dev *cd = cfile->cd;
441 struct dma_mapping *dma_map;
442
443 if (vsize == 0)
444 return -EINVAL;
445
446 if (get_order(size: vsize) > MAX_PAGE_ORDER)
447 return -ENOMEM;
448
449 dma_map = kzalloc(size: sizeof(struct dma_mapping), GFP_KERNEL);
450 if (dma_map == NULL)
451 return -ENOMEM;
452
453 genwqe_mapping_init(m: dma_map, type: GENWQE_MAPPING_RAW);
454 dma_map->u_vaddr = (void *)vma->vm_start;
455 dma_map->size = vsize;
456 dma_map->nr_pages = DIV_ROUND_UP(vsize, PAGE_SIZE);
457 dma_map->k_vaddr = __genwqe_alloc_consistent(cd, size: vsize,
458 dma_handle: &dma_map->dma_addr);
459 if (dma_map->k_vaddr == NULL) {
460 rc = -ENOMEM;
461 goto free_dma_map;
462 }
463
464 if (capable(CAP_SYS_ADMIN) && (vsize > sizeof(dma_addr_t)))
465 *(dma_addr_t *)dma_map->k_vaddr = dma_map->dma_addr;
466
467 pfn = virt_to_phys(address: dma_map->k_vaddr) >> PAGE_SHIFT;
468 rc = remap_pfn_range(vma,
469 addr: vma->vm_start,
470 pfn,
471 size: vsize,
472 vma->vm_page_prot);
473 if (rc != 0) {
474 rc = -EFAULT;
475 goto free_dma_mem;
476 }
477
478 vma->vm_private_data = cfile;
479 vma->vm_ops = &genwqe_vma_ops;
480 __genwqe_add_mapping(cfile, dma_map);
481
482 return 0;
483
484 free_dma_mem:
485 __genwqe_free_consistent(cd, size: dma_map->size,
486 vaddr: dma_map->k_vaddr,
487 dma_handle: dma_map->dma_addr);
488 free_dma_map:
489 kfree(objp: dma_map);
490 return rc;
491}
492
493#define FLASH_BLOCK 0x40000 /* we use 256k blocks */
494
495/**
496 * do_flash_update() - Excute flash update (write image or CVPD)
497 * @cfile: Descriptor of opened file
498 * @load: details about image load
499 *
500 * Return: 0 if successful
501 */
502static int do_flash_update(struct genwqe_file *cfile,
503 struct genwqe_bitstream *load)
504{
505 int rc = 0;
506 int blocks_to_flash;
507 dma_addr_t dma_addr;
508 u64 flash = 0;
509 size_t tocopy = 0;
510 u8 __user *buf;
511 u8 *xbuf;
512 u32 crc;
513 u8 cmdopts;
514 struct genwqe_dev *cd = cfile->cd;
515 struct file *filp = cfile->filp;
516 struct pci_dev *pci_dev = cd->pci_dev;
517
518 if ((load->size & 0x3) != 0)
519 return -EINVAL;
520
521 if (((unsigned long)(load->data_addr) & ~PAGE_MASK) != 0)
522 return -EINVAL;
523
524 /* FIXME Bits have changed for new service layer! */
525 switch ((char)load->partition) {
526 case '0':
527 cmdopts = 0x14;
528 break; /* download/erase_first/part_0 */
529 case '1':
530 cmdopts = 0x1C;
531 break; /* download/erase_first/part_1 */
532 case 'v':
533 cmdopts = 0x0C;
534 break; /* download/erase_first/vpd */
535 default:
536 return -EINVAL;
537 }
538
539 buf = (u8 __user *)load->data_addr;
540 xbuf = __genwqe_alloc_consistent(cd, FLASH_BLOCK, dma_handle: &dma_addr);
541 if (xbuf == NULL)
542 return -ENOMEM;
543
544 blocks_to_flash = load->size / FLASH_BLOCK;
545 while (load->size) {
546 struct genwqe_ddcb_cmd *req;
547
548 /*
549 * We must be 4 byte aligned. Buffer must be 0 appened
550 * to have defined values when calculating CRC.
551 */
552 tocopy = min_t(size_t, load->size, FLASH_BLOCK);
553
554 rc = copy_from_user(to: xbuf, from: buf, n: tocopy);
555 if (rc) {
556 rc = -EFAULT;
557 goto free_buffer;
558 }
559 crc = genwqe_crc32(buff: xbuf, len: tocopy, init: 0xffffffff);
560
561 dev_dbg(&pci_dev->dev,
562 "[%s] DMA: %lx CRC: %08x SZ: %ld %d\n",
563 __func__, (unsigned long)dma_addr, crc, tocopy,
564 blocks_to_flash);
565
566 /* prepare DDCB for SLU process */
567 req = ddcb_requ_alloc();
568 if (req == NULL) {
569 rc = -ENOMEM;
570 goto free_buffer;
571 }
572
573 req->cmd = SLCMD_MOVE_FLASH;
574 req->cmdopts = cmdopts;
575
576 /* prepare invariant values */
577 if (genwqe_get_slu_id(cd) <= 0x2) {
578 *(__be64 *)&req->__asiv[0] = cpu_to_be64(dma_addr);
579 *(__be64 *)&req->__asiv[8] = cpu_to_be64(tocopy);
580 *(__be64 *)&req->__asiv[16] = cpu_to_be64(flash);
581 *(__be32 *)&req->__asiv[24] = cpu_to_be32(0);
582 req->__asiv[24] = load->uid;
583 *(__be32 *)&req->__asiv[28] = cpu_to_be32(crc);
584
585 /* for simulation only */
586 *(__be64 *)&req->__asiv[88] = cpu_to_be64(load->slu_id);
587 *(__be64 *)&req->__asiv[96] = cpu_to_be64(load->app_id);
588 req->asiv_length = 32; /* bytes included in crc calc */
589 } else { /* setup DDCB for ATS architecture */
590 *(__be64 *)&req->asiv[0] = cpu_to_be64(dma_addr);
591 *(__be32 *)&req->asiv[8] = cpu_to_be32(tocopy);
592 *(__be32 *)&req->asiv[12] = cpu_to_be32(0); /* resvd */
593 *(__be64 *)&req->asiv[16] = cpu_to_be64(flash);
594 *(__be32 *)&req->asiv[24] = cpu_to_be32(load->uid<<24);
595 *(__be32 *)&req->asiv[28] = cpu_to_be32(crc);
596
597 /* for simulation only */
598 *(__be64 *)&req->asiv[80] = cpu_to_be64(load->slu_id);
599 *(__be64 *)&req->asiv[88] = cpu_to_be64(load->app_id);
600
601 /* Rd only */
602 req->ats = 0x4ULL << 44;
603 req->asiv_length = 40; /* bytes included in crc calc */
604 }
605 req->asv_length = 8;
606
607 /* For Genwqe5 we get back the calculated CRC */
608 *(u64 *)&req->asv[0] = 0ULL; /* 0x80 */
609
610 rc = __genwqe_execute_raw_ddcb(cd, cmd: req, f_flags: filp->f_flags);
611
612 load->retc = req->retc;
613 load->attn = req->attn;
614 load->progress = req->progress;
615
616 if (rc < 0) {
617 ddcb_requ_free(req);
618 goto free_buffer;
619 }
620
621 if (req->retc != DDCB_RETC_COMPLETE) {
622 rc = -EIO;
623 ddcb_requ_free(req);
624 goto free_buffer;
625 }
626
627 load->size -= tocopy;
628 flash += tocopy;
629 buf += tocopy;
630 blocks_to_flash--;
631 ddcb_requ_free(req);
632 }
633
634 free_buffer:
635 __genwqe_free_consistent(cd, FLASH_BLOCK, vaddr: xbuf, dma_handle: dma_addr);
636 return rc;
637}
638
639static int do_flash_read(struct genwqe_file *cfile,
640 struct genwqe_bitstream *load)
641{
642 int rc, blocks_to_flash;
643 dma_addr_t dma_addr;
644 u64 flash = 0;
645 size_t tocopy = 0;
646 u8 __user *buf;
647 u8 *xbuf;
648 u8 cmdopts;
649 struct genwqe_dev *cd = cfile->cd;
650 struct file *filp = cfile->filp;
651 struct pci_dev *pci_dev = cd->pci_dev;
652 struct genwqe_ddcb_cmd *cmd;
653
654 if ((load->size & 0x3) != 0)
655 return -EINVAL;
656
657 if (((unsigned long)(load->data_addr) & ~PAGE_MASK) != 0)
658 return -EINVAL;
659
660 /* FIXME Bits have changed for new service layer! */
661 switch ((char)load->partition) {
662 case '0':
663 cmdopts = 0x12;
664 break; /* upload/part_0 */
665 case '1':
666 cmdopts = 0x1A;
667 break; /* upload/part_1 */
668 case 'v':
669 cmdopts = 0x0A;
670 break; /* upload/vpd */
671 default:
672 return -EINVAL;
673 }
674
675 buf = (u8 __user *)load->data_addr;
676 xbuf = __genwqe_alloc_consistent(cd, FLASH_BLOCK, dma_handle: &dma_addr);
677 if (xbuf == NULL)
678 return -ENOMEM;
679
680 blocks_to_flash = load->size / FLASH_BLOCK;
681 while (load->size) {
682 /*
683 * We must be 4 byte aligned. Buffer must be 0 appened
684 * to have defined values when calculating CRC.
685 */
686 tocopy = min_t(size_t, load->size, FLASH_BLOCK);
687
688 dev_dbg(&pci_dev->dev,
689 "[%s] DMA: %lx SZ: %ld %d\n",
690 __func__, (unsigned long)dma_addr, tocopy,
691 blocks_to_flash);
692
693 /* prepare DDCB for SLU process */
694 cmd = ddcb_requ_alloc();
695 if (cmd == NULL) {
696 rc = -ENOMEM;
697 goto free_buffer;
698 }
699 cmd->cmd = SLCMD_MOVE_FLASH;
700 cmd->cmdopts = cmdopts;
701
702 /* prepare invariant values */
703 if (genwqe_get_slu_id(cd) <= 0x2) {
704 *(__be64 *)&cmd->__asiv[0] = cpu_to_be64(dma_addr);
705 *(__be64 *)&cmd->__asiv[8] = cpu_to_be64(tocopy);
706 *(__be64 *)&cmd->__asiv[16] = cpu_to_be64(flash);
707 *(__be32 *)&cmd->__asiv[24] = cpu_to_be32(0);
708 cmd->__asiv[24] = load->uid;
709 *(__be32 *)&cmd->__asiv[28] = cpu_to_be32(0) /* CRC */;
710 cmd->asiv_length = 32; /* bytes included in crc calc */
711 } else { /* setup DDCB for ATS architecture */
712 *(__be64 *)&cmd->asiv[0] = cpu_to_be64(dma_addr);
713 *(__be32 *)&cmd->asiv[8] = cpu_to_be32(tocopy);
714 *(__be32 *)&cmd->asiv[12] = cpu_to_be32(0); /* resvd */
715 *(__be64 *)&cmd->asiv[16] = cpu_to_be64(flash);
716 *(__be32 *)&cmd->asiv[24] = cpu_to_be32(load->uid<<24);
717 *(__be32 *)&cmd->asiv[28] = cpu_to_be32(0); /* CRC */
718
719 /* rd/wr */
720 cmd->ats = 0x5ULL << 44;
721 cmd->asiv_length = 40; /* bytes included in crc calc */
722 }
723 cmd->asv_length = 8;
724
725 /* we only get back the calculated CRC */
726 *(u64 *)&cmd->asv[0] = 0ULL; /* 0x80 */
727
728 rc = __genwqe_execute_raw_ddcb(cd, cmd, f_flags: filp->f_flags);
729
730 load->retc = cmd->retc;
731 load->attn = cmd->attn;
732 load->progress = cmd->progress;
733
734 if ((rc < 0) && (rc != -EBADMSG)) {
735 ddcb_requ_free(req: cmd);
736 goto free_buffer;
737 }
738
739 rc = copy_to_user(to: buf, from: xbuf, n: tocopy);
740 if (rc) {
741 rc = -EFAULT;
742 ddcb_requ_free(req: cmd);
743 goto free_buffer;
744 }
745
746 /* We know that we can get retc 0x104 with CRC err */
747 if (((cmd->retc == DDCB_RETC_FAULT) &&
748 (cmd->attn != 0x02)) || /* Normally ignore CRC error */
749 ((cmd->retc == DDCB_RETC_COMPLETE) &&
750 (cmd->attn != 0x00))) { /* Everything was fine */
751 rc = -EIO;
752 ddcb_requ_free(req: cmd);
753 goto free_buffer;
754 }
755
756 load->size -= tocopy;
757 flash += tocopy;
758 buf += tocopy;
759 blocks_to_flash--;
760 ddcb_requ_free(req: cmd);
761 }
762 rc = 0;
763
764 free_buffer:
765 __genwqe_free_consistent(cd, FLASH_BLOCK, vaddr: xbuf, dma_handle: dma_addr);
766 return rc;
767}
768
769static int genwqe_pin_mem(struct genwqe_file *cfile, struct genwqe_mem *m)
770{
771 int rc;
772 struct genwqe_dev *cd = cfile->cd;
773 struct pci_dev *pci_dev = cfile->cd->pci_dev;
774 struct dma_mapping *dma_map;
775 unsigned long map_addr;
776 unsigned long map_size;
777
778 if ((m->addr == 0x0) || (m->size == 0))
779 return -EINVAL;
780 if (m->size > ULONG_MAX - PAGE_SIZE - (m->addr & ~PAGE_MASK))
781 return -EINVAL;
782
783 map_addr = (m->addr & PAGE_MASK);
784 map_size = round_up(m->size + (m->addr & ~PAGE_MASK), PAGE_SIZE);
785
786 dma_map = kzalloc(size: sizeof(struct dma_mapping), GFP_KERNEL);
787 if (dma_map == NULL)
788 return -ENOMEM;
789
790 genwqe_mapping_init(m: dma_map, type: GENWQE_MAPPING_SGL_PINNED);
791 rc = genwqe_user_vmap(cd, m: dma_map, uaddr: (void *)map_addr, size: map_size);
792 if (rc != 0) {
793 dev_err(&pci_dev->dev,
794 "[%s] genwqe_user_vmap rc=%d\n", __func__, rc);
795 kfree(objp: dma_map);
796 return rc;
797 }
798
799 genwqe_add_pin(cfile, m: dma_map);
800 return 0;
801}
802
803static int genwqe_unpin_mem(struct genwqe_file *cfile, struct genwqe_mem *m)
804{
805 struct genwqe_dev *cd = cfile->cd;
806 struct dma_mapping *dma_map;
807 unsigned long map_addr;
808 unsigned long map_size;
809
810 if (m->addr == 0x0)
811 return -EINVAL;
812
813 map_addr = (m->addr & PAGE_MASK);
814 map_size = round_up(m->size + (m->addr & ~PAGE_MASK), PAGE_SIZE);
815
816 dma_map = genwqe_search_pin(cfile, u_addr: map_addr, size: map_size, NULL);
817 if (dma_map == NULL)
818 return -ENOENT;
819
820 genwqe_del_pin(cfile, m: dma_map);
821 genwqe_user_vunmap(cd, m: dma_map);
822 kfree(objp: dma_map);
823 return 0;
824}
825
826/**
827 * ddcb_cmd_cleanup() - Remove dynamically created fixup entries
828 * @cfile: Descriptor of opened file
829 * @req: DDCB work request
830 *
831 * Only if there are any. Pinnings are not removed.
832 */
833static int ddcb_cmd_cleanup(struct genwqe_file *cfile, struct ddcb_requ *req)
834{
835 unsigned int i;
836 struct dma_mapping *dma_map;
837 struct genwqe_dev *cd = cfile->cd;
838
839 for (i = 0; i < DDCB_FIXUPS; i++) {
840 dma_map = &req->dma_mappings[i];
841
842 if (dma_mapping_used(m: dma_map)) {
843 __genwqe_del_mapping(cfile, dma_map);
844 genwqe_user_vunmap(cd, m: dma_map);
845 }
846 if (req->sgls[i].sgl != NULL)
847 genwqe_free_sync_sgl(cd, sgl: &req->sgls[i]);
848 }
849 return 0;
850}
851
852/**
853 * ddcb_cmd_fixups() - Establish DMA fixups/sglists for user memory references
854 * @cfile: Descriptor of opened file
855 * @req: DDCB work request
856 *
857 * Before the DDCB gets executed we need to handle the fixups. We
858 * replace the user-space addresses with DMA addresses or do
859 * additional setup work e.g. generating a scatter-gather list which
860 * is used to describe the memory referred to in the fixup.
861 */
862static int ddcb_cmd_fixups(struct genwqe_file *cfile, struct ddcb_requ *req)
863{
864 int rc;
865 unsigned int asiv_offs, i;
866 struct genwqe_dev *cd = cfile->cd;
867 struct genwqe_ddcb_cmd *cmd = &req->cmd;
868 struct dma_mapping *m;
869
870 for (i = 0, asiv_offs = 0x00; asiv_offs <= 0x58;
871 i++, asiv_offs += 0x08) {
872
873 u64 u_addr;
874 dma_addr_t d_addr;
875 u32 u_size = 0;
876 u64 ats_flags;
877
878 ats_flags = ATS_GET_FLAGS(cmd->ats, asiv_offs);
879
880 switch (ats_flags) {
881
882 case ATS_TYPE_DATA:
883 break; /* nothing to do here */
884
885 case ATS_TYPE_FLAT_RDWR:
886 case ATS_TYPE_FLAT_RD: {
887 u_addr = be64_to_cpu(*((__be64 *)&cmd->
888 asiv[asiv_offs]));
889 u_size = be32_to_cpu(*((__be32 *)&cmd->
890 asiv[asiv_offs + 0x08]));
891
892 /*
893 * No data available. Ignore u_addr in this
894 * case and set addr to 0. Hardware must not
895 * fetch the buffer.
896 */
897 if (u_size == 0x0) {
898 *((__be64 *)&cmd->asiv[asiv_offs]) =
899 cpu_to_be64(0x0);
900 break;
901 }
902
903 m = __genwqe_search_mapping(cfile, u_addr, size: u_size,
904 dma_addr: &d_addr, NULL);
905 if (m == NULL) {
906 rc = -EFAULT;
907 goto err_out;
908 }
909
910 *((__be64 *)&cmd->asiv[asiv_offs]) =
911 cpu_to_be64(d_addr);
912 break;
913 }
914
915 case ATS_TYPE_SGL_RDWR:
916 case ATS_TYPE_SGL_RD: {
917 int page_offs;
918
919 u_addr = be64_to_cpu(*((__be64 *)
920 &cmd->asiv[asiv_offs]));
921 u_size = be32_to_cpu(*((__be32 *)
922 &cmd->asiv[asiv_offs + 0x08]));
923
924 /*
925 * No data available. Ignore u_addr in this
926 * case and set addr to 0. Hardware must not
927 * fetch the empty sgl.
928 */
929 if (u_size == 0x0) {
930 *((__be64 *)&cmd->asiv[asiv_offs]) =
931 cpu_to_be64(0x0);
932 break;
933 }
934
935 m = genwqe_search_pin(cfile, u_addr, size: u_size, NULL);
936 if (m != NULL) {
937 page_offs = (u_addr -
938 (u64)m->u_vaddr)/PAGE_SIZE;
939 } else {
940 m = &req->dma_mappings[i];
941
942 genwqe_mapping_init(m,
943 type: GENWQE_MAPPING_SGL_TEMP);
944
945 if (ats_flags == ATS_TYPE_SGL_RD)
946 m->write = 0;
947
948 rc = genwqe_user_vmap(cd, m, uaddr: (void *)u_addr,
949 size: u_size);
950 if (rc != 0)
951 goto err_out;
952
953 __genwqe_add_mapping(cfile, dma_map: m);
954 page_offs = 0;
955 }
956
957 /* create genwqe style scatter gather list */
958 rc = genwqe_alloc_sync_sgl(cd, sgl: &req->sgls[i],
959 user_addr: (void __user *)u_addr,
960 user_size: u_size, write: m->write);
961 if (rc != 0)
962 goto err_out;
963
964 genwqe_setup_sgl(cd, sgl: &req->sgls[i],
965 dma_list: &m->dma_list[page_offs]);
966
967 *((__be64 *)&cmd->asiv[asiv_offs]) =
968 cpu_to_be64(req->sgls[i].sgl_dma_addr);
969
970 break;
971 }
972 default:
973 rc = -EINVAL;
974 goto err_out;
975 }
976 }
977 return 0;
978
979 err_out:
980 ddcb_cmd_cleanup(cfile, req);
981 return rc;
982}
983
984/**
985 * genwqe_execute_ddcb() - Execute DDCB using userspace address fixups
986 * @cfile: Descriptor of opened file
987 * @cmd: Command identifier (passed from user)
988 *
989 * The code will build up the translation tables or lookup the
990 * contignous memory allocation table to find the right translations
991 * and DMA addresses.
992 */
993static int genwqe_execute_ddcb(struct genwqe_file *cfile,
994 struct genwqe_ddcb_cmd *cmd)
995{
996 int rc;
997 struct genwqe_dev *cd = cfile->cd;
998 struct file *filp = cfile->filp;
999 struct ddcb_requ *req = container_of(cmd, struct ddcb_requ, cmd);
1000
1001 rc = ddcb_cmd_fixups(cfile, req);
1002 if (rc != 0)
1003 return rc;
1004
1005 rc = __genwqe_execute_raw_ddcb(cd, cmd, f_flags: filp->f_flags);
1006 ddcb_cmd_cleanup(cfile, req);
1007 return rc;
1008}
1009
1010static int do_execute_ddcb(struct genwqe_file *cfile,
1011 unsigned long arg, int raw)
1012{
1013 int rc;
1014 struct genwqe_ddcb_cmd *cmd;
1015 struct genwqe_dev *cd = cfile->cd;
1016 struct file *filp = cfile->filp;
1017
1018 cmd = ddcb_requ_alloc();
1019 if (cmd == NULL)
1020 return -ENOMEM;
1021
1022 if (copy_from_user(to: cmd, from: (void __user *)arg, n: sizeof(*cmd))) {
1023 ddcb_requ_free(req: cmd);
1024 return -EFAULT;
1025 }
1026
1027 if (!raw)
1028 rc = genwqe_execute_ddcb(cfile, cmd);
1029 else
1030 rc = __genwqe_execute_raw_ddcb(cd, cmd, f_flags: filp->f_flags);
1031
1032 /* Copy back only the modifed fields. Do not copy ASIV
1033 back since the copy got modified by the driver. */
1034 if (copy_to_user(to: (void __user *)arg, from: cmd,
1035 n: sizeof(*cmd) - DDCB_ASIV_LENGTH)) {
1036 ddcb_requ_free(req: cmd);
1037 return -EFAULT;
1038 }
1039
1040 ddcb_requ_free(req: cmd);
1041 return rc;
1042}
1043
1044/**
1045 * genwqe_ioctl() - IO control
1046 * @filp: file handle
1047 * @cmd: command identifier (passed from user)
1048 * @arg: argument (passed from user)
1049 *
1050 * Return: 0 success
1051 */
1052static long genwqe_ioctl(struct file *filp, unsigned int cmd,
1053 unsigned long arg)
1054{
1055 int rc = 0;
1056 struct genwqe_file *cfile = (struct genwqe_file *)filp->private_data;
1057 struct genwqe_dev *cd = cfile->cd;
1058 struct pci_dev *pci_dev = cd->pci_dev;
1059 struct genwqe_reg_io __user *io;
1060 u64 val;
1061 u32 reg_offs;
1062
1063 /* Return -EIO if card hit EEH */
1064 if (pci_channel_offline(pdev: pci_dev))
1065 return -EIO;
1066
1067 if (_IOC_TYPE(cmd) != GENWQE_IOC_CODE)
1068 return -EINVAL;
1069
1070 switch (cmd) {
1071
1072 case GENWQE_GET_CARD_STATE:
1073 put_user(cd->card_state, (enum genwqe_card_state __user *)arg);
1074 return 0;
1075
1076 /* Register access */
1077 case GENWQE_READ_REG64: {
1078 io = (struct genwqe_reg_io __user *)arg;
1079
1080 if (get_user(reg_offs, &io->num))
1081 return -EFAULT;
1082
1083 if ((reg_offs >= cd->mmio_len) || (reg_offs & 0x7))
1084 return -EINVAL;
1085
1086 val = __genwqe_readq(cd, byte_offs: reg_offs);
1087 put_user(val, &io->val64);
1088 return 0;
1089 }
1090
1091 case GENWQE_WRITE_REG64: {
1092 io = (struct genwqe_reg_io __user *)arg;
1093
1094 if (!capable(CAP_SYS_ADMIN))
1095 return -EPERM;
1096
1097 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
1098 return -EPERM;
1099
1100 if (get_user(reg_offs, &io->num))
1101 return -EFAULT;
1102
1103 if ((reg_offs >= cd->mmio_len) || (reg_offs & 0x7))
1104 return -EINVAL;
1105
1106 if (get_user(val, &io->val64))
1107 return -EFAULT;
1108
1109 __genwqe_writeq(cd, byte_offs: reg_offs, val);
1110 return 0;
1111 }
1112
1113 case GENWQE_READ_REG32: {
1114 io = (struct genwqe_reg_io __user *)arg;
1115
1116 if (get_user(reg_offs, &io->num))
1117 return -EFAULT;
1118
1119 if ((reg_offs >= cd->mmio_len) || (reg_offs & 0x3))
1120 return -EINVAL;
1121
1122 val = __genwqe_readl(cd, byte_offs: reg_offs);
1123 put_user(val, &io->val64);
1124 return 0;
1125 }
1126
1127 case GENWQE_WRITE_REG32: {
1128 io = (struct genwqe_reg_io __user *)arg;
1129
1130 if (!capable(CAP_SYS_ADMIN))
1131 return -EPERM;
1132
1133 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
1134 return -EPERM;
1135
1136 if (get_user(reg_offs, &io->num))
1137 return -EFAULT;
1138
1139 if ((reg_offs >= cd->mmio_len) || (reg_offs & 0x3))
1140 return -EINVAL;
1141
1142 if (get_user(val, &io->val64))
1143 return -EFAULT;
1144
1145 __genwqe_writel(cd, byte_offs: reg_offs, val);
1146 return 0;
1147 }
1148
1149 /* Flash update/reading */
1150 case GENWQE_SLU_UPDATE: {
1151 struct genwqe_bitstream load;
1152
1153 if (!genwqe_is_privileged(cd))
1154 return -EPERM;
1155
1156 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
1157 return -EPERM;
1158
1159 if (copy_from_user(to: &load, from: (void __user *)arg,
1160 n: sizeof(load)))
1161 return -EFAULT;
1162
1163 rc = do_flash_update(cfile, load: &load);
1164
1165 if (copy_to_user(to: (void __user *)arg, from: &load, n: sizeof(load)))
1166 return -EFAULT;
1167
1168 return rc;
1169 }
1170
1171 case GENWQE_SLU_READ: {
1172 struct genwqe_bitstream load;
1173
1174 if (!genwqe_is_privileged(cd))
1175 return -EPERM;
1176
1177 if (genwqe_flash_readback_fails(cd))
1178 return -ENOSPC; /* known to fail for old versions */
1179
1180 if (copy_from_user(to: &load, from: (void __user *)arg, n: sizeof(load)))
1181 return -EFAULT;
1182
1183 rc = do_flash_read(cfile, load: &load);
1184
1185 if (copy_to_user(to: (void __user *)arg, from: &load, n: sizeof(load)))
1186 return -EFAULT;
1187
1188 return rc;
1189 }
1190
1191 /* memory pinning and unpinning */
1192 case GENWQE_PIN_MEM: {
1193 struct genwqe_mem m;
1194
1195 if (copy_from_user(to: &m, from: (void __user *)arg, n: sizeof(m)))
1196 return -EFAULT;
1197
1198 return genwqe_pin_mem(cfile, m: &m);
1199 }
1200
1201 case GENWQE_UNPIN_MEM: {
1202 struct genwqe_mem m;
1203
1204 if (copy_from_user(to: &m, from: (void __user *)arg, n: sizeof(m)))
1205 return -EFAULT;
1206
1207 return genwqe_unpin_mem(cfile, m: &m);
1208 }
1209
1210 /* launch an DDCB and wait for completion */
1211 case GENWQE_EXECUTE_DDCB:
1212 return do_execute_ddcb(cfile, arg, raw: 0);
1213
1214 case GENWQE_EXECUTE_RAW_DDCB: {
1215
1216 if (!capable(CAP_SYS_ADMIN))
1217 return -EPERM;
1218
1219 return do_execute_ddcb(cfile, arg, raw: 1);
1220 }
1221
1222 default:
1223 return -EINVAL;
1224 }
1225
1226 return rc;
1227}
1228
1229static const struct file_operations genwqe_fops = {
1230 .owner = THIS_MODULE,
1231 .open = genwqe_open,
1232 .fasync = genwqe_fasync,
1233 .mmap = genwqe_mmap,
1234 .unlocked_ioctl = genwqe_ioctl,
1235 .compat_ioctl = compat_ptr_ioctl,
1236 .release = genwqe_release,
1237};
1238
1239static int genwqe_device_initialized(struct genwqe_dev *cd)
1240{
1241 return cd->dev != NULL;
1242}
1243
1244/**
1245 * genwqe_device_create() - Create and configure genwqe char device
1246 * @cd: genwqe device descriptor
1247 *
1248 * This function must be called before we create any more genwqe
1249 * character devices, because it is allocating the major and minor
1250 * number which are supposed to be used by the client drivers.
1251 */
1252int genwqe_device_create(struct genwqe_dev *cd)
1253{
1254 int rc;
1255 struct pci_dev *pci_dev = cd->pci_dev;
1256
1257 /*
1258 * Here starts the individual setup per client. It must
1259 * initialize its own cdev data structure with its own fops.
1260 * The appropriate devnum needs to be created. The ranges must
1261 * not overlap.
1262 */
1263 rc = alloc_chrdev_region(&cd->devnum_genwqe, 0,
1264 GENWQE_MAX_MINOR, GENWQE_DEVNAME);
1265 if (rc < 0) {
1266 dev_err(&pci_dev->dev, "err: alloc_chrdev_region failed\n");
1267 goto err_dev;
1268 }
1269
1270 cdev_init(&cd->cdev_genwqe, &genwqe_fops);
1271 cd->cdev_genwqe.owner = THIS_MODULE;
1272
1273 rc = cdev_add(&cd->cdev_genwqe, cd->devnum_genwqe, 1);
1274 if (rc < 0) {
1275 dev_err(&pci_dev->dev, "err: cdev_add failed\n");
1276 goto err_add;
1277 }
1278
1279 /*
1280 * Finally the device in /dev/... must be created. The rule is
1281 * to use card%d_clientname for each created device.
1282 */
1283 cd->dev = device_create_with_groups(cls: cd->class_genwqe,
1284 parent: &cd->pci_dev->dev,
1285 devt: cd->devnum_genwqe, drvdata: cd,
1286 groups: genwqe_attribute_groups,
1287 GENWQE_DEVNAME "%u_card",
1288 cd->card_idx);
1289 if (IS_ERR(ptr: cd->dev)) {
1290 rc = PTR_ERR(ptr: cd->dev);
1291 goto err_cdev;
1292 }
1293
1294 genwqe_init_debugfs(cd);
1295
1296 return 0;
1297
1298 err_cdev:
1299 cdev_del(&cd->cdev_genwqe);
1300 err_add:
1301 unregister_chrdev_region(cd->devnum_genwqe, GENWQE_MAX_MINOR);
1302 err_dev:
1303 cd->dev = NULL;
1304 return rc;
1305}
1306
1307static int genwqe_inform_and_stop_processes(struct genwqe_dev *cd)
1308{
1309 int rc;
1310 unsigned int i;
1311 struct pci_dev *pci_dev = cd->pci_dev;
1312
1313 if (!genwqe_open_files(cd))
1314 return 0;
1315
1316 dev_warn(&pci_dev->dev, "[%s] send SIGIO and wait ...\n", __func__);
1317
1318 rc = genwqe_kill_fasync(cd, SIGIO);
1319 if (rc > 0) {
1320 /* give kill_timeout seconds to close file descriptors ... */
1321 for (i = 0; (i < GENWQE_KILL_TIMEOUT) &&
1322 genwqe_open_files(cd); i++) {
1323 dev_info(&pci_dev->dev, " %d sec ...", i);
1324
1325 cond_resched();
1326 msleep(msecs: 1000);
1327 }
1328
1329 /* if no open files we can safely continue, else ... */
1330 if (!genwqe_open_files(cd))
1331 return 0;
1332
1333 dev_warn(&pci_dev->dev,
1334 "[%s] send SIGKILL and wait ...\n", __func__);
1335
1336 rc = genwqe_terminate(cd);
1337 if (rc) {
1338 /* Give kill_timout more seconds to end processes */
1339 for (i = 0; (i < GENWQE_KILL_TIMEOUT) &&
1340 genwqe_open_files(cd); i++) {
1341 dev_warn(&pci_dev->dev, " %d sec ...", i);
1342
1343 cond_resched();
1344 msleep(msecs: 1000);
1345 }
1346 }
1347 }
1348 return 0;
1349}
1350
1351/**
1352 * genwqe_device_remove() - Remove genwqe's char device
1353 * @cd: GenWQE device information
1354 *
1355 * This function must be called after the client devices are removed
1356 * because it will free the major/minor number range for the genwqe
1357 * drivers.
1358 *
1359 * This function must be robust enough to be called twice.
1360 */
1361int genwqe_device_remove(struct genwqe_dev *cd)
1362{
1363 int rc;
1364 struct pci_dev *pci_dev = cd->pci_dev;
1365
1366 if (!genwqe_device_initialized(cd))
1367 return 1;
1368
1369 genwqe_inform_and_stop_processes(cd);
1370
1371 /*
1372 * We currently do wait until all filedescriptors are
1373 * closed. This leads to a problem when we abort the
1374 * application which will decrease this reference from
1375 * 1/unused to 0/illegal and not from 2/used 1/empty.
1376 */
1377 rc = kref_read(kref: &cd->cdev_genwqe.kobj.kref);
1378 if (rc != 1) {
1379 dev_err(&pci_dev->dev,
1380 "[%s] err: cdev_genwqe...refcount=%d\n", __func__, rc);
1381 panic(fmt: "Fatal err: cannot free resources with pending references!");
1382 }
1383
1384 genqwe_exit_debugfs(cd);
1385 device_destroy(cls: cd->class_genwqe, devt: cd->devnum_genwqe);
1386 cdev_del(&cd->cdev_genwqe);
1387 unregister_chrdev_region(cd->devnum_genwqe, GENWQE_MAX_MINOR);
1388 cd->dev = NULL;
1389
1390 return 0;
1391}
1392

source code of linux/drivers/misc/genwqe/card_dev.c