1 /*
2  * Copyright 2014 IBM Corp.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  */
9 
10 #include <linux/spinlock.h>
11 #include <linux/module.h>
12 #include <linux/export.h>
13 #include <linux/kernel.h>
14 #include <linux/bitmap.h>
15 #include <linux/sched/signal.h>
16 #include <linux/poll.h>
17 #include <linux/pid.h>
18 #include <linux/fs.h>
19 #include <linux/mm.h>
20 #include <linux/slab.h>
21 #include <linux/sched/mm.h>
22 #include <linux/mmu_context.h>
23 #include <asm/cputable.h>
24 #include <asm/current.h>
25 #include <asm/copro.h>
26 
27 #include "cxl.h"
28 #include "trace.h"
29 
30 #define CXL_NUM_MINORS 256 /* Total to reserve */
31 
32 #define CXL_AFU_MINOR_D(afu) (CXL_CARD_MINOR(afu->adapter) + 1 + (3 * afu->slice))
33 #define CXL_AFU_MINOR_M(afu) (CXL_AFU_MINOR_D(afu) + 1)
34 #define CXL_AFU_MINOR_S(afu) (CXL_AFU_MINOR_D(afu) + 2)
35 #define CXL_AFU_MKDEV_D(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_D(afu))
36 #define CXL_AFU_MKDEV_M(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_M(afu))
37 #define CXL_AFU_MKDEV_S(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_S(afu))
38 
39 #define CXL_DEVT_AFU(dev) ((MINOR(dev) % CXL_DEV_MINORS - 1) / 3)
40 
41 #define CXL_DEVT_IS_CARD(dev) (MINOR(dev) % CXL_DEV_MINORS == 0)
42 
43 static dev_t cxl_dev;
44 
45 static struct class *cxl_class;
46 
__afu_open(struct inode * inode,struct file * file,bool master)47 static int __afu_open(struct inode *inode, struct file *file, bool master)
48 {
49 	struct cxl *adapter;
50 	struct cxl_afu *afu;
51 	struct cxl_context *ctx;
52 	int adapter_num = CXL_DEVT_ADAPTER(inode->i_rdev);
53 	int slice = CXL_DEVT_AFU(inode->i_rdev);
54 	int rc = -ENODEV;
55 
56 	pr_devel("afu_open afu%i.%i\n", slice, adapter_num);
57 
58 	if (!(adapter = get_cxl_adapter(adapter_num)))
59 		return -ENODEV;
60 
61 	if (slice > adapter->slices)
62 		goto err_put_adapter;
63 
64 	spin_lock(&adapter->afu_list_lock);
65 	if (!(afu = adapter->afu[slice])) {
66 		spin_unlock(&adapter->afu_list_lock);
67 		goto err_put_adapter;
68 	}
69 
70 	/*
71 	 * taking a ref to the afu so that it doesn't go away
72 	 * for rest of the function. This ref is released before
73 	 * we return.
74 	 */
75 	cxl_afu_get(afu);
76 	spin_unlock(&adapter->afu_list_lock);
77 
78 	if (!afu->current_mode)
79 		goto err_put_afu;
80 
81 	if (!cxl_ops->link_ok(adapter, afu)) {
82 		rc = -EIO;
83 		goto err_put_afu;
84 	}
85 
86 	if (!(ctx = cxl_context_alloc())) {
87 		rc = -ENOMEM;
88 		goto err_put_afu;
89 	}
90 
91 	rc = cxl_context_init(ctx, afu, master);
92 	if (rc)
93 		goto err_put_afu;
94 
95 	cxl_context_set_mapping(ctx, inode->i_mapping);
96 
97 	pr_devel("afu_open pe: %i\n", ctx->pe);
98 	file->private_data = ctx;
99 
100 	/* indicate success */
101 	rc = 0;
102 
103 err_put_afu:
104 	/* release the ref taken earlier */
105 	cxl_afu_put(afu);
106 err_put_adapter:
107 	put_device(&adapter->dev);
108 	return rc;
109 }
110 
afu_open(struct inode * inode,struct file * file)111 int afu_open(struct inode *inode, struct file *file)
112 {
113 	return __afu_open(inode, file, false);
114 }
115 
afu_master_open(struct inode * inode,struct file * file)116 static int afu_master_open(struct inode *inode, struct file *file)
117 {
118 	return __afu_open(inode, file, true);
119 }
120 
afu_release(struct inode * inode,struct file * file)121 int afu_release(struct inode *inode, struct file *file)
122 {
123 	struct cxl_context *ctx = file->private_data;
124 
125 	pr_devel("%s: closing cxl file descriptor. pe: %i\n",
126 		 __func__, ctx->pe);
127 	cxl_context_detach(ctx);
128 
129 
130 	/*
131 	 * Delete the context's mapping pointer, unless it's created by the
132 	 * kernel API, in which case leave it so it can be freed by reclaim_ctx()
133 	 */
134 	if (!ctx->kernelapi) {
135 		mutex_lock(&ctx->mapping_lock);
136 		ctx->mapping = NULL;
137 		mutex_unlock(&ctx->mapping_lock);
138 	}
139 
140 	/*
141 	 * At this this point all bottom halfs have finished and we should be
142 	 * getting no more IRQs from the hardware for this context.  Once it's
143 	 * removed from the IDR (and RCU synchronised) it's safe to free the
144 	 * sstp and context.
145 	 */
146 	cxl_context_free(ctx);
147 
148 	return 0;
149 }
150 
afu_ioctl_start_work(struct cxl_context * ctx,struct cxl_ioctl_start_work __user * uwork)151 static long afu_ioctl_start_work(struct cxl_context *ctx,
152 				 struct cxl_ioctl_start_work __user *uwork)
153 {
154 	struct cxl_ioctl_start_work work;
155 	u64 amr = 0;
156 	int rc;
157 
158 	pr_devel("%s: pe: %i\n", __func__, ctx->pe);
159 
160 	/* Do this outside the status_mutex to avoid a circular dependency with
161 	 * the locking in cxl_mmap_fault() */
162 	if (copy_from_user(&work, uwork, sizeof(work)))
163 		return -EFAULT;
164 
165 	mutex_lock(&ctx->status_mutex);
166 	if (ctx->status != OPENED) {
167 		rc = -EIO;
168 		goto out;
169 	}
170 
171 	/*
172 	 * if any of the reserved fields are set or any of the unused
173 	 * flags are set it's invalid
174 	 */
175 	if (work.reserved1 || work.reserved2 || work.reserved3 ||
176 	    work.reserved4 || work.reserved5 ||
177 	    (work.flags & ~CXL_START_WORK_ALL)) {
178 		rc = -EINVAL;
179 		goto out;
180 	}
181 
182 	if (!(work.flags & CXL_START_WORK_NUM_IRQS))
183 		work.num_interrupts = ctx->afu->pp_irqs;
184 	else if ((work.num_interrupts < ctx->afu->pp_irqs) ||
185 		 (work.num_interrupts > ctx->afu->irqs_max)) {
186 		rc =  -EINVAL;
187 		goto out;
188 	}
189 
190 	if ((rc = afu_register_irqs(ctx, work.num_interrupts)))
191 		goto out;
192 
193 	if (work.flags & CXL_START_WORK_AMR)
194 		amr = work.amr & mfspr(SPRN_UAMOR);
195 
196 	if (work.flags & CXL_START_WORK_TID)
197 		ctx->assign_tidr = true;
198 
199 	ctx->mmio_err_ff = !!(work.flags & CXL_START_WORK_ERR_FF);
200 
201 	/*
202 	 * Increment the mapped context count for adapter. This also checks
203 	 * if adapter_context_lock is taken.
204 	 */
205 	rc = cxl_adapter_context_get(ctx->afu->adapter);
206 	if (rc) {
207 		afu_release_irqs(ctx, ctx);
208 		goto out;
209 	}
210 
211 	/*
212 	 * We grab the PID here and not in the file open to allow for the case
213 	 * where a process (master, some daemon, etc) has opened the chardev on
214 	 * behalf of another process, so the AFU's mm gets bound to the process
215 	 * that performs this ioctl and not the process that opened the file.
216 	 * Also we grab the PID of the group leader so that if the task that
217 	 * has performed the attach operation exits the mm context of the
218 	 * process is still accessible.
219 	 */
220 	ctx->pid = get_task_pid(current, PIDTYPE_PID);
221 
222 	/* acquire a reference to the task's mm */
223 	ctx->mm = get_task_mm(current);
224 
225 	/* ensure this mm_struct can't be freed */
226 	cxl_context_mm_count_get(ctx);
227 
228 	if (ctx->mm) {
229 		/* decrement the use count from above */
230 		mmput(ctx->mm);
231 		/* make TLBIs for this context global */
232 		mm_context_add_copro(ctx->mm);
233 	}
234 
235 	/*
236 	 * Increment driver use count. Enables global TLBIs for hash
237 	 * and callbacks to handle the segment table
238 	 */
239 	cxl_ctx_get();
240 
241 	/*
242 	 * A barrier is needed to make sure all TLBIs are global
243 	 * before we attach and the context starts being used by the
244 	 * adapter.
245 	 *
246 	 * Needed after mm_context_add_copro() for radix and
247 	 * cxl_ctx_get() for hash/p8.
248 	 *
249 	 * The barrier should really be mb(), since it involves a
250 	 * device. However, it's only useful when we have local
251 	 * vs. global TLBIs, i.e SMP=y. So keep smp_mb().
252 	 */
253 	smp_mb();
254 
255 	trace_cxl_attach(ctx, work.work_element_descriptor, work.num_interrupts, amr);
256 
257 	if ((rc = cxl_ops->attach_process(ctx, false, work.work_element_descriptor,
258 							amr))) {
259 		afu_release_irqs(ctx, ctx);
260 		cxl_adapter_context_put(ctx->afu->adapter);
261 		put_pid(ctx->pid);
262 		ctx->pid = NULL;
263 		cxl_ctx_put();
264 		cxl_context_mm_count_put(ctx);
265 		if (ctx->mm)
266 			mm_context_remove_copro(ctx->mm);
267 		goto out;
268 	}
269 
270 	rc = 0;
271 	if (work.flags & CXL_START_WORK_TID) {
272 		work.tid = ctx->tidr;
273 		if (copy_to_user(uwork, &work, sizeof(work)))
274 			rc = -EFAULT;
275 	}
276 
277 	ctx->status = STARTED;
278 
279 out:
280 	mutex_unlock(&ctx->status_mutex);
281 	return rc;
282 }
283 
afu_ioctl_process_element(struct cxl_context * ctx,int __user * upe)284 static long afu_ioctl_process_element(struct cxl_context *ctx,
285 				      int __user *upe)
286 {
287 	pr_devel("%s: pe: %i\n", __func__, ctx->pe);
288 
289 	if (copy_to_user(upe, &ctx->external_pe, sizeof(__u32)))
290 		return -EFAULT;
291 
292 	return 0;
293 }
294 
afu_ioctl_get_afu_id(struct cxl_context * ctx,struct cxl_afu_id __user * upafuid)295 static long afu_ioctl_get_afu_id(struct cxl_context *ctx,
296 				 struct cxl_afu_id __user *upafuid)
297 {
298 	struct cxl_afu_id afuid = { 0 };
299 
300 	afuid.card_id = ctx->afu->adapter->adapter_num;
301 	afuid.afu_offset = ctx->afu->slice;
302 	afuid.afu_mode = ctx->afu->current_mode;
303 
304 	/* set the flag bit in case the afu is a slave */
305 	if (ctx->afu->current_mode == CXL_MODE_DIRECTED && !ctx->master)
306 		afuid.flags |= CXL_AFUID_FLAG_SLAVE;
307 
308 	if (copy_to_user(upafuid, &afuid, sizeof(afuid)))
309 		return -EFAULT;
310 
311 	return 0;
312 }
313 
afu_ioctl(struct file * file,unsigned int cmd,unsigned long arg)314 long afu_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
315 {
316 	struct cxl_context *ctx = file->private_data;
317 
318 	if (ctx->status == CLOSED)
319 		return -EIO;
320 
321 	if (!cxl_ops->link_ok(ctx->afu->adapter, ctx->afu))
322 		return -EIO;
323 
324 	pr_devel("afu_ioctl\n");
325 	switch (cmd) {
326 	case CXL_IOCTL_START_WORK:
327 		return afu_ioctl_start_work(ctx, (struct cxl_ioctl_start_work __user *)arg);
328 	case CXL_IOCTL_GET_PROCESS_ELEMENT:
329 		return afu_ioctl_process_element(ctx, (__u32 __user *)arg);
330 	case CXL_IOCTL_GET_AFU_ID:
331 		return afu_ioctl_get_afu_id(ctx, (struct cxl_afu_id __user *)
332 					    arg);
333 	}
334 	return -EINVAL;
335 }
336 
afu_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)337 static long afu_compat_ioctl(struct file *file, unsigned int cmd,
338 			     unsigned long arg)
339 {
340 	return afu_ioctl(file, cmd, arg);
341 }
342 
afu_mmap(struct file * file,struct vm_area_struct * vm)343 int afu_mmap(struct file *file, struct vm_area_struct *vm)
344 {
345 	struct cxl_context *ctx = file->private_data;
346 
347 	/* AFU must be started before we can MMIO */
348 	if (ctx->status != STARTED)
349 		return -EIO;
350 
351 	if (!cxl_ops->link_ok(ctx->afu->adapter, ctx->afu))
352 		return -EIO;
353 
354 	return cxl_context_iomap(ctx, vm);
355 }
356 
ctx_event_pending(struct cxl_context * ctx)357 static inline bool ctx_event_pending(struct cxl_context *ctx)
358 {
359 	if (ctx->pending_irq || ctx->pending_fault || ctx->pending_afu_err)
360 		return true;
361 
362 	if (ctx->afu_driver_ops && atomic_read(&ctx->afu_driver_events))
363 		return true;
364 
365 	return false;
366 }
367 
afu_poll(struct file * file,struct poll_table_struct * poll)368 __poll_t afu_poll(struct file *file, struct poll_table_struct *poll)
369 {
370 	struct cxl_context *ctx = file->private_data;
371 	__poll_t mask = 0;
372 	unsigned long flags;
373 
374 
375 	poll_wait(file, &ctx->wq, poll);
376 
377 	pr_devel("afu_poll wait done pe: %i\n", ctx->pe);
378 
379 	spin_lock_irqsave(&ctx->lock, flags);
380 	if (ctx_event_pending(ctx))
381 		mask |= EPOLLIN | EPOLLRDNORM;
382 	else if (ctx->status == CLOSED)
383 		/* Only error on closed when there are no futher events pending
384 		 */
385 		mask |= EPOLLERR;
386 	spin_unlock_irqrestore(&ctx->lock, flags);
387 
388 	pr_devel("afu_poll pe: %i returning %#x\n", ctx->pe, mask);
389 
390 	return mask;
391 }
392 
afu_driver_event_copy(struct cxl_context * ctx,char __user * buf,struct cxl_event * event,struct cxl_event_afu_driver_reserved * pl)393 static ssize_t afu_driver_event_copy(struct cxl_context *ctx,
394 				     char __user *buf,
395 				     struct cxl_event *event,
396 				     struct cxl_event_afu_driver_reserved *pl)
397 {
398 	/* Check event */
399 	if (!pl) {
400 		ctx->afu_driver_ops->event_delivered(ctx, pl, -EINVAL);
401 		return -EFAULT;
402 	}
403 
404 	/* Check event size */
405 	event->header.size += pl->data_size;
406 	if (event->header.size > CXL_READ_MIN_SIZE) {
407 		ctx->afu_driver_ops->event_delivered(ctx, pl, -EINVAL);
408 		return -EFAULT;
409 	}
410 
411 	/* Copy event header */
412 	if (copy_to_user(buf, event, sizeof(struct cxl_event_header))) {
413 		ctx->afu_driver_ops->event_delivered(ctx, pl, -EFAULT);
414 		return -EFAULT;
415 	}
416 
417 	/* Copy event data */
418 	buf += sizeof(struct cxl_event_header);
419 	if (copy_to_user(buf, &pl->data, pl->data_size)) {
420 		ctx->afu_driver_ops->event_delivered(ctx, pl, -EFAULT);
421 		return -EFAULT;
422 	}
423 
424 	ctx->afu_driver_ops->event_delivered(ctx, pl, 0); /* Success */
425 	return event->header.size;
426 }
427 
afu_read(struct file * file,char __user * buf,size_t count,loff_t * off)428 ssize_t afu_read(struct file *file, char __user *buf, size_t count,
429 			loff_t *off)
430 {
431 	struct cxl_context *ctx = file->private_data;
432 	struct cxl_event_afu_driver_reserved *pl = NULL;
433 	struct cxl_event event;
434 	unsigned long flags;
435 	int rc;
436 	DEFINE_WAIT(wait);
437 
438 	if (!cxl_ops->link_ok(ctx->afu->adapter, ctx->afu))
439 		return -EIO;
440 
441 	if (count < CXL_READ_MIN_SIZE)
442 		return -EINVAL;
443 
444 	spin_lock_irqsave(&ctx->lock, flags);
445 
446 	for (;;) {
447 		prepare_to_wait(&ctx->wq, &wait, TASK_INTERRUPTIBLE);
448 		if (ctx_event_pending(ctx) || (ctx->status == CLOSED))
449 			break;
450 
451 		if (!cxl_ops->link_ok(ctx->afu->adapter, ctx->afu)) {
452 			rc = -EIO;
453 			goto out;
454 		}
455 
456 		if (file->f_flags & O_NONBLOCK) {
457 			rc = -EAGAIN;
458 			goto out;
459 		}
460 
461 		if (signal_pending(current)) {
462 			rc = -ERESTARTSYS;
463 			goto out;
464 		}
465 
466 		spin_unlock_irqrestore(&ctx->lock, flags);
467 		pr_devel("afu_read going to sleep...\n");
468 		schedule();
469 		pr_devel("afu_read woken up\n");
470 		spin_lock_irqsave(&ctx->lock, flags);
471 	}
472 
473 	finish_wait(&ctx->wq, &wait);
474 
475 	memset(&event, 0, sizeof(event));
476 	event.header.process_element = ctx->pe;
477 	event.header.size = sizeof(struct cxl_event_header);
478 	if (ctx->afu_driver_ops && atomic_read(&ctx->afu_driver_events)) {
479 		pr_devel("afu_read delivering AFU driver specific event\n");
480 		pl = ctx->afu_driver_ops->fetch_event(ctx);
481 		atomic_dec(&ctx->afu_driver_events);
482 		event.header.type = CXL_EVENT_AFU_DRIVER;
483 	} else if (ctx->pending_irq) {
484 		pr_devel("afu_read delivering AFU interrupt\n");
485 		event.header.size += sizeof(struct cxl_event_afu_interrupt);
486 		event.header.type = CXL_EVENT_AFU_INTERRUPT;
487 		event.irq.irq = find_first_bit(ctx->irq_bitmap, ctx->irq_count) + 1;
488 		clear_bit(event.irq.irq - 1, ctx->irq_bitmap);
489 		if (bitmap_empty(ctx->irq_bitmap, ctx->irq_count))
490 			ctx->pending_irq = false;
491 	} else if (ctx->pending_fault) {
492 		pr_devel("afu_read delivering data storage fault\n");
493 		event.header.size += sizeof(struct cxl_event_data_storage);
494 		event.header.type = CXL_EVENT_DATA_STORAGE;
495 		event.fault.addr = ctx->fault_addr;
496 		event.fault.dsisr = ctx->fault_dsisr;
497 		ctx->pending_fault = false;
498 	} else if (ctx->pending_afu_err) {
499 		pr_devel("afu_read delivering afu error\n");
500 		event.header.size += sizeof(struct cxl_event_afu_error);
501 		event.header.type = CXL_EVENT_AFU_ERROR;
502 		event.afu_error.error = ctx->afu_err;
503 		ctx->pending_afu_err = false;
504 	} else if (ctx->status == CLOSED) {
505 		pr_devel("afu_read fatal error\n");
506 		spin_unlock_irqrestore(&ctx->lock, flags);
507 		return -EIO;
508 	} else
509 		WARN(1, "afu_read must be buggy\n");
510 
511 	spin_unlock_irqrestore(&ctx->lock, flags);
512 
513 	if (event.header.type == CXL_EVENT_AFU_DRIVER)
514 		return afu_driver_event_copy(ctx, buf, &event, pl);
515 
516 	if (copy_to_user(buf, &event, event.header.size))
517 		return -EFAULT;
518 	return event.header.size;
519 
520 out:
521 	finish_wait(&ctx->wq, &wait);
522 	spin_unlock_irqrestore(&ctx->lock, flags);
523 	return rc;
524 }
525 
526 /*
527  * Note: if this is updated, we need to update api.c to patch the new ones in
528  * too
529  */
530 const struct file_operations afu_fops = {
531 	.owner		= THIS_MODULE,
532 	.open           = afu_open,
533 	.poll		= afu_poll,
534 	.read		= afu_read,
535 	.release        = afu_release,
536 	.unlocked_ioctl = afu_ioctl,
537 	.compat_ioctl   = afu_compat_ioctl,
538 	.mmap           = afu_mmap,
539 };
540 
541 static const struct file_operations afu_master_fops = {
542 	.owner		= THIS_MODULE,
543 	.open           = afu_master_open,
544 	.poll		= afu_poll,
545 	.read		= afu_read,
546 	.release        = afu_release,
547 	.unlocked_ioctl = afu_ioctl,
548 	.compat_ioctl   = afu_compat_ioctl,
549 	.mmap           = afu_mmap,
550 };
551 
552 
cxl_devnode(struct device * dev,umode_t * mode)553 static char *cxl_devnode(struct device *dev, umode_t *mode)
554 {
555 	if (cpu_has_feature(CPU_FTR_HVMODE) &&
556 	    CXL_DEVT_IS_CARD(dev->devt)) {
557 		/*
558 		 * These minor numbers will eventually be used to program the
559 		 * PSL and AFUs once we have dynamic reprogramming support
560 		 */
561 		return NULL;
562 	}
563 	return kasprintf(GFP_KERNEL, "cxl/%s", dev_name(dev));
564 }
565 
566 extern struct class *cxl_class;
567 
cxl_add_chardev(struct cxl_afu * afu,dev_t devt,struct cdev * cdev,struct device ** chardev,char * postfix,char * desc,const struct file_operations * fops)568 static int cxl_add_chardev(struct cxl_afu *afu, dev_t devt, struct cdev *cdev,
569 			   struct device **chardev, char *postfix, char *desc,
570 			   const struct file_operations *fops)
571 {
572 	struct device *dev;
573 	int rc;
574 
575 	cdev_init(cdev, fops);
576 	if ((rc = cdev_add(cdev, devt, 1))) {
577 		dev_err(&afu->dev, "Unable to add %s chardev: %i\n", desc, rc);
578 		return rc;
579 	}
580 
581 	dev = device_create(cxl_class, &afu->dev, devt, afu,
582 			"afu%i.%i%s", afu->adapter->adapter_num, afu->slice, postfix);
583 	if (IS_ERR(dev)) {
584 		dev_err(&afu->dev, "Unable to create %s chardev in sysfs: %i\n", desc, rc);
585 		rc = PTR_ERR(dev);
586 		goto err;
587 	}
588 
589 	*chardev = dev;
590 
591 	return 0;
592 err:
593 	cdev_del(cdev);
594 	return rc;
595 }
596 
cxl_chardev_d_afu_add(struct cxl_afu * afu)597 int cxl_chardev_d_afu_add(struct cxl_afu *afu)
598 {
599 	return cxl_add_chardev(afu, CXL_AFU_MKDEV_D(afu), &afu->afu_cdev_d,
600 			       &afu->chardev_d, "d", "dedicated",
601 			       &afu_master_fops); /* Uses master fops */
602 }
603 
cxl_chardev_m_afu_add(struct cxl_afu * afu)604 int cxl_chardev_m_afu_add(struct cxl_afu *afu)
605 {
606 	return cxl_add_chardev(afu, CXL_AFU_MKDEV_M(afu), &afu->afu_cdev_m,
607 			       &afu->chardev_m, "m", "master",
608 			       &afu_master_fops);
609 }
610 
cxl_chardev_s_afu_add(struct cxl_afu * afu)611 int cxl_chardev_s_afu_add(struct cxl_afu *afu)
612 {
613 	return cxl_add_chardev(afu, CXL_AFU_MKDEV_S(afu), &afu->afu_cdev_s,
614 			       &afu->chardev_s, "s", "shared",
615 			       &afu_fops);
616 }
617 
cxl_chardev_afu_remove(struct cxl_afu * afu)618 void cxl_chardev_afu_remove(struct cxl_afu *afu)
619 {
620 	if (afu->chardev_d) {
621 		cdev_del(&afu->afu_cdev_d);
622 		device_unregister(afu->chardev_d);
623 		afu->chardev_d = NULL;
624 	}
625 	if (afu->chardev_m) {
626 		cdev_del(&afu->afu_cdev_m);
627 		device_unregister(afu->chardev_m);
628 		afu->chardev_m = NULL;
629 	}
630 	if (afu->chardev_s) {
631 		cdev_del(&afu->afu_cdev_s);
632 		device_unregister(afu->chardev_s);
633 		afu->chardev_s = NULL;
634 	}
635 }
636 
cxl_register_afu(struct cxl_afu * afu)637 int cxl_register_afu(struct cxl_afu *afu)
638 {
639 	afu->dev.class = cxl_class;
640 
641 	return device_register(&afu->dev);
642 }
643 
cxl_register_adapter(struct cxl * adapter)644 int cxl_register_adapter(struct cxl *adapter)
645 {
646 	adapter->dev.class = cxl_class;
647 
648 	/*
649 	 * Future: When we support dynamically reprogramming the PSL & AFU we
650 	 * will expose the interface to do that via a chardev:
651 	 * adapter->dev.devt = CXL_CARD_MKDEV(adapter);
652 	 */
653 
654 	return device_register(&adapter->dev);
655 }
656 
cxl_get_dev(void)657 dev_t cxl_get_dev(void)
658 {
659 	return cxl_dev;
660 }
661 
cxl_file_init(void)662 int __init cxl_file_init(void)
663 {
664 	int rc;
665 
666 	/*
667 	 * If these change we really need to update API.  Either change some
668 	 * flags or update API version number CXL_API_VERSION.
669 	 */
670 	BUILD_BUG_ON(CXL_API_VERSION != 3);
671 	BUILD_BUG_ON(sizeof(struct cxl_ioctl_start_work) != 64);
672 	BUILD_BUG_ON(sizeof(struct cxl_event_header) != 8);
673 	BUILD_BUG_ON(sizeof(struct cxl_event_afu_interrupt) != 8);
674 	BUILD_BUG_ON(sizeof(struct cxl_event_data_storage) != 32);
675 	BUILD_BUG_ON(sizeof(struct cxl_event_afu_error) != 16);
676 
677 	if ((rc = alloc_chrdev_region(&cxl_dev, 0, CXL_NUM_MINORS, "cxl"))) {
678 		pr_err("Unable to allocate CXL major number: %i\n", rc);
679 		return rc;
680 	}
681 
682 	pr_devel("CXL device allocated, MAJOR %i\n", MAJOR(cxl_dev));
683 
684 	cxl_class = class_create(THIS_MODULE, "cxl");
685 	if (IS_ERR(cxl_class)) {
686 		pr_err("Unable to create CXL class\n");
687 		rc = PTR_ERR(cxl_class);
688 		goto err;
689 	}
690 	cxl_class->devnode = cxl_devnode;
691 
692 	return 0;
693 
694 err:
695 	unregister_chrdev_region(cxl_dev, CXL_NUM_MINORS);
696 	return rc;
697 }
698 
cxl_file_exit(void)699 void cxl_file_exit(void)
700 {
701 	unregister_chrdev_region(cxl_dev, CXL_NUM_MINORS);
702 	class_destroy(cxl_class);
703 }
704