xref: /openbmc/linux/arch/powerpc/kvm/book3s_xive.c (revision 36fe4655)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2017 Benjamin Herrenschmidt, IBM Corporation.
4  */
5 
6 #define pr_fmt(fmt) "xive-kvm: " fmt
7 
8 #include <linux/kernel.h>
9 #include <linux/kvm_host.h>
10 #include <linux/err.h>
11 #include <linux/gfp.h>
12 #include <linux/spinlock.h>
13 #include <linux/delay.h>
14 #include <linux/percpu.h>
15 #include <linux/cpumask.h>
16 #include <linux/uaccess.h>
17 #include <asm/kvm_book3s.h>
18 #include <asm/kvm_ppc.h>
19 #include <asm/hvcall.h>
20 #include <asm/xics.h>
21 #include <asm/xive.h>
22 #include <asm/xive-regs.h>
23 #include <asm/debug.h>
24 #include <asm/debugfs.h>
25 #include <asm/time.h>
26 #include <asm/opal.h>
27 
28 #include <linux/debugfs.h>
29 #include <linux/seq_file.h>
30 
31 #include "book3s_xive.h"
32 
33 
34 /*
35  * Virtual mode variants of the hcalls for use on radix/radix
36  * with AIL. They require the VCPU's VP to be "pushed"
37  *
38  * We still instantiate them here because we use some of the
39  * generated utility functions as well in this file.
40  */
41 #define XIVE_RUNTIME_CHECKS
42 #define X_PFX xive_vm_
43 #define X_STATIC static
44 #define X_STAT_PFX stat_vm_
45 #define __x_tima		xive_tima
46 #define __x_eoi_page(xd)	((void __iomem *)((xd)->eoi_mmio))
47 #define __x_trig_page(xd)	((void __iomem *)((xd)->trig_mmio))
48 #define __x_writeb	__raw_writeb
49 #define __x_readw	__raw_readw
50 #define __x_readq	__raw_readq
51 #define __x_writeq	__raw_writeq
52 
53 #include "book3s_xive_template.c"
54 
55 /*
56  * We leave a gap of a couple of interrupts in the queue to
57  * account for the IPI and additional safety guard.
58  */
59 #define XIVE_Q_GAP	2
60 
61 /*
62  * Push a vcpu's context to the XIVE on guest entry.
63  * This assumes we are in virtual mode (MMU on)
64  */
65 void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu)
66 {
67 	void __iomem *tima = local_paca->kvm_hstate.xive_tima_virt;
68 	u64 pq;
69 
70 	/*
71 	 * Nothing to do if the platform doesn't have a XIVE
72 	 * or this vCPU doesn't have its own XIVE context
73 	 * (e.g. because it's not using an in-kernel interrupt controller).
74 	 */
75 	if (!tima || !vcpu->arch.xive_cam_word)
76 		return;
77 
78 	eieio();
79 	__raw_writeq(vcpu->arch.xive_saved_state.w01, tima + TM_QW1_OS);
80 	__raw_writel(vcpu->arch.xive_cam_word, tima + TM_QW1_OS + TM_WORD2);
81 	vcpu->arch.xive_pushed = 1;
82 	eieio();
83 
84 	/*
85 	 * We clear the irq_pending flag. There is a small chance of a
86 	 * race vs. the escalation interrupt happening on another
87 	 * processor setting it again, but the only consequence is to
88 	 * cause a spurious wakeup on the next H_CEDE, which is not an
89 	 * issue.
90 	 */
91 	vcpu->arch.irq_pending = 0;
92 
93 	/*
94 	 * In single escalation mode, if the escalation interrupt is
95 	 * on, we mask it.
96 	 */
97 	if (vcpu->arch.xive_esc_on) {
98 		pq = __raw_readq((void __iomem *)(vcpu->arch.xive_esc_vaddr +
99 						  XIVE_ESB_SET_PQ_01));
100 		mb();
101 
102 		/*
103 		 * We have a possible subtle race here: The escalation
104 		 * interrupt might have fired and be on its way to the
105 		 * host queue while we mask it, and if we unmask it
106 		 * early enough (re-cede right away), there is a
107 		 * theorical possibility that it fires again, thus
108 		 * landing in the target queue more than once which is
109 		 * a big no-no.
110 		 *
111 		 * Fortunately, solving this is rather easy. If the
112 		 * above load setting PQ to 01 returns a previous
113 		 * value where P is set, then we know the escalation
114 		 * interrupt is somewhere on its way to the host. In
115 		 * that case we simply don't clear the xive_esc_on
116 		 * flag below. It will be eventually cleared by the
117 		 * handler for the escalation interrupt.
118 		 *
119 		 * Then, when doing a cede, we check that flag again
120 		 * before re-enabling the escalation interrupt, and if
121 		 * set, we abort the cede.
122 		 */
123 		if (!(pq & XIVE_ESB_VAL_P))
124 			/* Now P is 0, we can clear the flag */
125 			vcpu->arch.xive_esc_on = 0;
126 	}
127 }
128 EXPORT_SYMBOL_GPL(kvmppc_xive_push_vcpu);
129 
130 /*
131  * This is a simple trigger for a generic XIVE IRQ. This must
132  * only be called for interrupts that support a trigger page
133  */
134 static bool xive_irq_trigger(struct xive_irq_data *xd)
135 {
136 	/* This should be only for MSIs */
137 	if (WARN_ON(xd->flags & XIVE_IRQ_FLAG_LSI))
138 		return false;
139 
140 	/* Those interrupts should always have a trigger page */
141 	if (WARN_ON(!xd->trig_mmio))
142 		return false;
143 
144 	out_be64(xd->trig_mmio, 0);
145 
146 	return true;
147 }
148 
149 static irqreturn_t xive_esc_irq(int irq, void *data)
150 {
151 	struct kvm_vcpu *vcpu = data;
152 
153 	vcpu->arch.irq_pending = 1;
154 	smp_mb();
155 	if (vcpu->arch.ceded)
156 		kvmppc_fast_vcpu_kick(vcpu);
157 
158 	/* Since we have the no-EOI flag, the interrupt is effectively
159 	 * disabled now. Clearing xive_esc_on means we won't bother
160 	 * doing so on the next entry.
161 	 *
162 	 * This also allows the entry code to know that if a PQ combination
163 	 * of 10 is observed while xive_esc_on is true, it means the queue
164 	 * contains an unprocessed escalation interrupt. We don't make use of
165 	 * that knowledge today but might (see comment in book3s_hv_rmhandler.S)
166 	 */
167 	vcpu->arch.xive_esc_on = false;
168 
169 	/* This orders xive_esc_on = false vs. subsequent stale_p = true */
170 	smp_wmb();	/* goes with smp_mb() in cleanup_single_escalation */
171 
172 	return IRQ_HANDLED;
173 }
174 
175 int kvmppc_xive_attach_escalation(struct kvm_vcpu *vcpu, u8 prio,
176 				  bool single_escalation)
177 {
178 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
179 	struct xive_q *q = &xc->queues[prio];
180 	char *name = NULL;
181 	int rc;
182 
183 	/* Already there ? */
184 	if (xc->esc_virq[prio])
185 		return 0;
186 
187 	/* Hook up the escalation interrupt */
188 	xc->esc_virq[prio] = irq_create_mapping(NULL, q->esc_irq);
189 	if (!xc->esc_virq[prio]) {
190 		pr_err("Failed to map escalation interrupt for queue %d of VCPU %d\n",
191 		       prio, xc->server_num);
192 		return -EIO;
193 	}
194 
195 	if (single_escalation)
196 		name = kasprintf(GFP_KERNEL, "kvm-%d-%d",
197 				 vcpu->kvm->arch.lpid, xc->server_num);
198 	else
199 		name = kasprintf(GFP_KERNEL, "kvm-%d-%d-%d",
200 				 vcpu->kvm->arch.lpid, xc->server_num, prio);
201 	if (!name) {
202 		pr_err("Failed to allocate escalation irq name for queue %d of VCPU %d\n",
203 		       prio, xc->server_num);
204 		rc = -ENOMEM;
205 		goto error;
206 	}
207 
208 	pr_devel("Escalation %s irq %d (prio %d)\n", name, xc->esc_virq[prio], prio);
209 
210 	rc = request_irq(xc->esc_virq[prio], xive_esc_irq,
211 			 IRQF_NO_THREAD, name, vcpu);
212 	if (rc) {
213 		pr_err("Failed to request escalation interrupt for queue %d of VCPU %d\n",
214 		       prio, xc->server_num);
215 		goto error;
216 	}
217 	xc->esc_virq_names[prio] = name;
218 
219 	/* In single escalation mode, we grab the ESB MMIO of the
220 	 * interrupt and mask it. Also populate the VCPU v/raddr
221 	 * of the ESB page for use by asm entry/exit code. Finally
222 	 * set the XIVE_IRQ_FLAG_NO_EOI flag which will prevent the
223 	 * core code from performing an EOI on the escalation
224 	 * interrupt, thus leaving it effectively masked after
225 	 * it fires once.
226 	 */
227 	if (single_escalation) {
228 		struct irq_data *d = irq_get_irq_data(xc->esc_virq[prio]);
229 		struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
230 
231 		xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_01);
232 		vcpu->arch.xive_esc_raddr = xd->eoi_page;
233 		vcpu->arch.xive_esc_vaddr = (__force u64)xd->eoi_mmio;
234 		xd->flags |= XIVE_IRQ_FLAG_NO_EOI;
235 	}
236 
237 	return 0;
238 error:
239 	irq_dispose_mapping(xc->esc_virq[prio]);
240 	xc->esc_virq[prio] = 0;
241 	kfree(name);
242 	return rc;
243 }
244 
245 static int xive_provision_queue(struct kvm_vcpu *vcpu, u8 prio)
246 {
247 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
248 	struct kvmppc_xive *xive = xc->xive;
249 	struct xive_q *q =  &xc->queues[prio];
250 	void *qpage;
251 	int rc;
252 
253 	if (WARN_ON(q->qpage))
254 		return 0;
255 
256 	/* Allocate the queue and retrieve infos on current node for now */
257 	qpage = (__be32 *)__get_free_pages(GFP_KERNEL, xive->q_page_order);
258 	if (!qpage) {
259 		pr_err("Failed to allocate queue %d for VCPU %d\n",
260 		       prio, xc->server_num);
261 		return -ENOMEM;
262 	}
263 	memset(qpage, 0, 1 << xive->q_order);
264 
265 	/*
266 	 * Reconfigure the queue. This will set q->qpage only once the
267 	 * queue is fully configured. This is a requirement for prio 0
268 	 * as we will stop doing EOIs for every IPI as soon as we observe
269 	 * qpage being non-NULL, and instead will only EOI when we receive
270 	 * corresponding queue 0 entries
271 	 */
272 	rc = xive_native_configure_queue(xc->vp_id, q, prio, qpage,
273 					 xive->q_order, true);
274 	if (rc)
275 		pr_err("Failed to configure queue %d for VCPU %d\n",
276 		       prio, xc->server_num);
277 	return rc;
278 }
279 
280 /* Called with xive->lock held */
281 static int xive_check_provisioning(struct kvm *kvm, u8 prio)
282 {
283 	struct kvmppc_xive *xive = kvm->arch.xive;
284 	struct kvm_vcpu *vcpu;
285 	int i, rc;
286 
287 	lockdep_assert_held(&xive->lock);
288 
289 	/* Already provisioned ? */
290 	if (xive->qmap & (1 << prio))
291 		return 0;
292 
293 	pr_devel("Provisioning prio... %d\n", prio);
294 
295 	/* Provision each VCPU and enable escalations if needed */
296 	kvm_for_each_vcpu(i, vcpu, kvm) {
297 		if (!vcpu->arch.xive_vcpu)
298 			continue;
299 		rc = xive_provision_queue(vcpu, prio);
300 		if (rc == 0 && !xive->single_escalation)
301 			kvmppc_xive_attach_escalation(vcpu, prio,
302 						      xive->single_escalation);
303 		if (rc)
304 			return rc;
305 	}
306 
307 	/* Order previous stores and mark it as provisioned */
308 	mb();
309 	xive->qmap |= (1 << prio);
310 	return 0;
311 }
312 
313 static void xive_inc_q_pending(struct kvm *kvm, u32 server, u8 prio)
314 {
315 	struct kvm_vcpu *vcpu;
316 	struct kvmppc_xive_vcpu *xc;
317 	struct xive_q *q;
318 
319 	/* Locate target server */
320 	vcpu = kvmppc_xive_find_server(kvm, server);
321 	if (!vcpu) {
322 		pr_warn("%s: Can't find server %d\n", __func__, server);
323 		return;
324 	}
325 	xc = vcpu->arch.xive_vcpu;
326 	if (WARN_ON(!xc))
327 		return;
328 
329 	q = &xc->queues[prio];
330 	atomic_inc(&q->pending_count);
331 }
332 
333 static int xive_try_pick_queue(struct kvm_vcpu *vcpu, u8 prio)
334 {
335 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
336 	struct xive_q *q;
337 	u32 max;
338 
339 	if (WARN_ON(!xc))
340 		return -ENXIO;
341 	if (!xc->valid)
342 		return -ENXIO;
343 
344 	q = &xc->queues[prio];
345 	if (WARN_ON(!q->qpage))
346 		return -ENXIO;
347 
348 	/* Calculate max number of interrupts in that queue. */
349 	max = (q->msk + 1) - XIVE_Q_GAP;
350 	return atomic_add_unless(&q->count, 1, max) ? 0 : -EBUSY;
351 }
352 
353 int kvmppc_xive_select_target(struct kvm *kvm, u32 *server, u8 prio)
354 {
355 	struct kvm_vcpu *vcpu;
356 	int i, rc;
357 
358 	/* Locate target server */
359 	vcpu = kvmppc_xive_find_server(kvm, *server);
360 	if (!vcpu) {
361 		pr_devel("Can't find server %d\n", *server);
362 		return -EINVAL;
363 	}
364 
365 	pr_devel("Finding irq target on 0x%x/%d...\n", *server, prio);
366 
367 	/* Try pick it */
368 	rc = xive_try_pick_queue(vcpu, prio);
369 	if (rc == 0)
370 		return rc;
371 
372 	pr_devel(" .. failed, looking up candidate...\n");
373 
374 	/* Failed, pick another VCPU */
375 	kvm_for_each_vcpu(i, vcpu, kvm) {
376 		if (!vcpu->arch.xive_vcpu)
377 			continue;
378 		rc = xive_try_pick_queue(vcpu, prio);
379 		if (rc == 0) {
380 			*server = vcpu->arch.xive_vcpu->server_num;
381 			pr_devel("  found on 0x%x/%d\n", *server, prio);
382 			return rc;
383 		}
384 	}
385 	pr_devel("  no available target !\n");
386 
387 	/* No available target ! */
388 	return -EBUSY;
389 }
390 
391 static u8 xive_lock_and_mask(struct kvmppc_xive *xive,
392 			     struct kvmppc_xive_src_block *sb,
393 			     struct kvmppc_xive_irq_state *state)
394 {
395 	struct xive_irq_data *xd;
396 	u32 hw_num;
397 	u8 old_prio;
398 	u64 val;
399 
400 	/*
401 	 * Take the lock, set masked, try again if racing
402 	 * with H_EOI
403 	 */
404 	for (;;) {
405 		arch_spin_lock(&sb->lock);
406 		old_prio = state->guest_priority;
407 		state->guest_priority = MASKED;
408 		mb();
409 		if (!state->in_eoi)
410 			break;
411 		state->guest_priority = old_prio;
412 		arch_spin_unlock(&sb->lock);
413 	}
414 
415 	/* No change ? Bail */
416 	if (old_prio == MASKED)
417 		return old_prio;
418 
419 	/* Get the right irq */
420 	kvmppc_xive_select_irq(state, &hw_num, &xd);
421 
422 	/* Set PQ to 10, return old P and old Q and remember them */
423 	val = xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_10);
424 	state->old_p = !!(val & 2);
425 	state->old_q = !!(val & 1);
426 
427 	/*
428 	 * Synchronize hardware to sensure the queues are updated when
429 	 * masking
430 	 */
431 	xive_native_sync_source(hw_num);
432 
433 	return old_prio;
434 }
435 
436 static void xive_lock_for_unmask(struct kvmppc_xive_src_block *sb,
437 				 struct kvmppc_xive_irq_state *state)
438 {
439 	/*
440 	 * Take the lock try again if racing with H_EOI
441 	 */
442 	for (;;) {
443 		arch_spin_lock(&sb->lock);
444 		if (!state->in_eoi)
445 			break;
446 		arch_spin_unlock(&sb->lock);
447 	}
448 }
449 
450 static void xive_finish_unmask(struct kvmppc_xive *xive,
451 			       struct kvmppc_xive_src_block *sb,
452 			       struct kvmppc_xive_irq_state *state,
453 			       u8 prio)
454 {
455 	struct xive_irq_data *xd;
456 	u32 hw_num;
457 
458 	/* If we aren't changing a thing, move on */
459 	if (state->guest_priority != MASKED)
460 		goto bail;
461 
462 	/* Get the right irq */
463 	kvmppc_xive_select_irq(state, &hw_num, &xd);
464 
465 	/* Old Q set, set PQ to 11 */
466 	if (state->old_q)
467 		xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_11);
468 
469 	/*
470 	 * If not old P, then perform an "effective" EOI,
471 	 * on the source. This will handle the cases where
472 	 * FW EOI is needed.
473 	 */
474 	if (!state->old_p)
475 		xive_vm_source_eoi(hw_num, xd);
476 
477 	/* Synchronize ordering and mark unmasked */
478 	mb();
479 bail:
480 	state->guest_priority = prio;
481 }
482 
483 /*
484  * Target an interrupt to a given server/prio, this will fallback
485  * to another server if necessary and perform the HW targetting
486  * updates as needed
487  *
488  * NOTE: Must be called with the state lock held
489  */
490 static int xive_target_interrupt(struct kvm *kvm,
491 				 struct kvmppc_xive_irq_state *state,
492 				 u32 server, u8 prio)
493 {
494 	struct kvmppc_xive *xive = kvm->arch.xive;
495 	u32 hw_num;
496 	int rc;
497 
498 	/*
499 	 * This will return a tentative server and actual
500 	 * priority. The count for that new target will have
501 	 * already been incremented.
502 	 */
503 	rc = kvmppc_xive_select_target(kvm, &server, prio);
504 
505 	/*
506 	 * We failed to find a target ? Not much we can do
507 	 * at least until we support the GIQ.
508 	 */
509 	if (rc)
510 		return rc;
511 
512 	/*
513 	 * Increment the old queue pending count if there
514 	 * was one so that the old queue count gets adjusted later
515 	 * when observed to be empty.
516 	 */
517 	if (state->act_priority != MASKED)
518 		xive_inc_q_pending(kvm,
519 				   state->act_server,
520 				   state->act_priority);
521 	/*
522 	 * Update state and HW
523 	 */
524 	state->act_priority = prio;
525 	state->act_server = server;
526 
527 	/* Get the right irq */
528 	kvmppc_xive_select_irq(state, &hw_num, NULL);
529 
530 	return xive_native_configure_irq(hw_num,
531 					 kvmppc_xive_vp(xive, server),
532 					 prio, state->number);
533 }
534 
535 /*
536  * Targetting rules: In order to avoid losing track of
537  * pending interrupts accross mask and unmask, which would
538  * allow queue overflows, we implement the following rules:
539  *
540  *  - Unless it was never enabled (or we run out of capacity)
541  *    an interrupt is always targetted at a valid server/queue
542  *    pair even when "masked" by the guest. This pair tends to
543  *    be the last one used but it can be changed under some
544  *    circumstances. That allows us to separate targetting
545  *    from masking, we only handle accounting during (re)targetting,
546  *    this also allows us to let an interrupt drain into its target
547  *    queue after masking, avoiding complex schemes to remove
548  *    interrupts out of remote processor queues.
549  *
550  *  - When masking, we set PQ to 10 and save the previous value
551  *    of P and Q.
552  *
553  *  - When unmasking, if saved Q was set, we set PQ to 11
554  *    otherwise we leave PQ to the HW state which will be either
555  *    10 if nothing happened or 11 if the interrupt fired while
556  *    masked. Effectively we are OR'ing the previous Q into the
557  *    HW Q.
558  *
559  *    Then if saved P is clear, we do an effective EOI (Q->P->Trigger)
560  *    which will unmask the interrupt and shoot a new one if Q was
561  *    set.
562  *
563  *    Otherwise (saved P is set) we leave PQ unchanged (so 10 or 11,
564  *    effectively meaning an H_EOI from the guest is still expected
565  *    for that interrupt).
566  *
567  *  - If H_EOI occurs while masked, we clear the saved P.
568  *
569  *  - When changing target, we account on the new target and
570  *    increment a separate "pending" counter on the old one.
571  *    This pending counter will be used to decrement the old
572  *    target's count when its queue has been observed empty.
573  */
574 
575 int kvmppc_xive_set_xive(struct kvm *kvm, u32 irq, u32 server,
576 			 u32 priority)
577 {
578 	struct kvmppc_xive *xive = kvm->arch.xive;
579 	struct kvmppc_xive_src_block *sb;
580 	struct kvmppc_xive_irq_state *state;
581 	u8 new_act_prio;
582 	int rc = 0;
583 	u16 idx;
584 
585 	if (!xive)
586 		return -ENODEV;
587 
588 	pr_devel("set_xive ! irq 0x%x server 0x%x prio %d\n",
589 		 irq, server, priority);
590 
591 	/* First, check provisioning of queues */
592 	if (priority != MASKED) {
593 		mutex_lock(&xive->lock);
594 		rc = xive_check_provisioning(xive->kvm,
595 			      xive_prio_from_guest(priority));
596 		mutex_unlock(&xive->lock);
597 	}
598 	if (rc) {
599 		pr_devel("  provisioning failure %d !\n", rc);
600 		return rc;
601 	}
602 
603 	sb = kvmppc_xive_find_source(xive, irq, &idx);
604 	if (!sb)
605 		return -EINVAL;
606 	state = &sb->irq_state[idx];
607 
608 	/*
609 	 * We first handle masking/unmasking since the locking
610 	 * might need to be retried due to EOIs, we'll handle
611 	 * targetting changes later. These functions will return
612 	 * with the SB lock held.
613 	 *
614 	 * xive_lock_and_mask() will also set state->guest_priority
615 	 * but won't otherwise change other fields of the state.
616 	 *
617 	 * xive_lock_for_unmask will not actually unmask, this will
618 	 * be done later by xive_finish_unmask() once the targetting
619 	 * has been done, so we don't try to unmask an interrupt
620 	 * that hasn't yet been targetted.
621 	 */
622 	if (priority == MASKED)
623 		xive_lock_and_mask(xive, sb, state);
624 	else
625 		xive_lock_for_unmask(sb, state);
626 
627 
628 	/*
629 	 * Then we handle targetting.
630 	 *
631 	 * First calculate a new "actual priority"
632 	 */
633 	new_act_prio = state->act_priority;
634 	if (priority != MASKED)
635 		new_act_prio = xive_prio_from_guest(priority);
636 
637 	pr_devel(" new_act_prio=%x act_server=%x act_prio=%x\n",
638 		 new_act_prio, state->act_server, state->act_priority);
639 
640 	/*
641 	 * Then check if we actually need to change anything,
642 	 *
643 	 * The condition for re-targetting the interrupt is that
644 	 * we have a valid new priority (new_act_prio is not 0xff)
645 	 * and either the server or the priority changed.
646 	 *
647 	 * Note: If act_priority was ff and the new priority is
648 	 *       also ff, we don't do anything and leave the interrupt
649 	 *       untargetted. An attempt of doing an int_on on an
650 	 *       untargetted interrupt will fail. If that is a problem
651 	 *       we could initialize interrupts with valid default
652 	 */
653 
654 	if (new_act_prio != MASKED &&
655 	    (state->act_server != server ||
656 	     state->act_priority != new_act_prio))
657 		rc = xive_target_interrupt(kvm, state, server, new_act_prio);
658 
659 	/*
660 	 * Perform the final unmasking of the interrupt source
661 	 * if necessary
662 	 */
663 	if (priority != MASKED)
664 		xive_finish_unmask(xive, sb, state, priority);
665 
666 	/*
667 	 * Finally Update saved_priority to match. Only int_on/off
668 	 * set this field to a different value.
669 	 */
670 	state->saved_priority = priority;
671 
672 	arch_spin_unlock(&sb->lock);
673 	return rc;
674 }
675 
676 int kvmppc_xive_get_xive(struct kvm *kvm, u32 irq, u32 *server,
677 			 u32 *priority)
678 {
679 	struct kvmppc_xive *xive = kvm->arch.xive;
680 	struct kvmppc_xive_src_block *sb;
681 	struct kvmppc_xive_irq_state *state;
682 	u16 idx;
683 
684 	if (!xive)
685 		return -ENODEV;
686 
687 	sb = kvmppc_xive_find_source(xive, irq, &idx);
688 	if (!sb)
689 		return -EINVAL;
690 	state = &sb->irq_state[idx];
691 	arch_spin_lock(&sb->lock);
692 	*server = state->act_server;
693 	*priority = state->guest_priority;
694 	arch_spin_unlock(&sb->lock);
695 
696 	return 0;
697 }
698 
699 int kvmppc_xive_int_on(struct kvm *kvm, u32 irq)
700 {
701 	struct kvmppc_xive *xive = kvm->arch.xive;
702 	struct kvmppc_xive_src_block *sb;
703 	struct kvmppc_xive_irq_state *state;
704 	u16 idx;
705 
706 	if (!xive)
707 		return -ENODEV;
708 
709 	sb = kvmppc_xive_find_source(xive, irq, &idx);
710 	if (!sb)
711 		return -EINVAL;
712 	state = &sb->irq_state[idx];
713 
714 	pr_devel("int_on(irq=0x%x)\n", irq);
715 
716 	/*
717 	 * Check if interrupt was not targetted
718 	 */
719 	if (state->act_priority == MASKED) {
720 		pr_devel("int_on on untargetted interrupt\n");
721 		return -EINVAL;
722 	}
723 
724 	/* If saved_priority is 0xff, do nothing */
725 	if (state->saved_priority == MASKED)
726 		return 0;
727 
728 	/*
729 	 * Lock and unmask it.
730 	 */
731 	xive_lock_for_unmask(sb, state);
732 	xive_finish_unmask(xive, sb, state, state->saved_priority);
733 	arch_spin_unlock(&sb->lock);
734 
735 	return 0;
736 }
737 
738 int kvmppc_xive_int_off(struct kvm *kvm, u32 irq)
739 {
740 	struct kvmppc_xive *xive = kvm->arch.xive;
741 	struct kvmppc_xive_src_block *sb;
742 	struct kvmppc_xive_irq_state *state;
743 	u16 idx;
744 
745 	if (!xive)
746 		return -ENODEV;
747 
748 	sb = kvmppc_xive_find_source(xive, irq, &idx);
749 	if (!sb)
750 		return -EINVAL;
751 	state = &sb->irq_state[idx];
752 
753 	pr_devel("int_off(irq=0x%x)\n", irq);
754 
755 	/*
756 	 * Lock and mask
757 	 */
758 	state->saved_priority = xive_lock_and_mask(xive, sb, state);
759 	arch_spin_unlock(&sb->lock);
760 
761 	return 0;
762 }
763 
764 static bool xive_restore_pending_irq(struct kvmppc_xive *xive, u32 irq)
765 {
766 	struct kvmppc_xive_src_block *sb;
767 	struct kvmppc_xive_irq_state *state;
768 	u16 idx;
769 
770 	sb = kvmppc_xive_find_source(xive, irq, &idx);
771 	if (!sb)
772 		return false;
773 	state = &sb->irq_state[idx];
774 	if (!state->valid)
775 		return false;
776 
777 	/*
778 	 * Trigger the IPI. This assumes we never restore a pass-through
779 	 * interrupt which should be safe enough
780 	 */
781 	xive_irq_trigger(&state->ipi_data);
782 
783 	return true;
784 }
785 
786 u64 kvmppc_xive_get_icp(struct kvm_vcpu *vcpu)
787 {
788 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
789 
790 	if (!xc)
791 		return 0;
792 
793 	/* Return the per-cpu state for state saving/migration */
794 	return (u64)xc->cppr << KVM_REG_PPC_ICP_CPPR_SHIFT |
795 	       (u64)xc->mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT |
796 	       (u64)0xff << KVM_REG_PPC_ICP_PPRI_SHIFT;
797 }
798 
799 int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval)
800 {
801 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
802 	struct kvmppc_xive *xive = vcpu->kvm->arch.xive;
803 	u8 cppr, mfrr;
804 	u32 xisr;
805 
806 	if (!xc || !xive)
807 		return -ENOENT;
808 
809 	/* Grab individual state fields. We don't use pending_pri */
810 	cppr = icpval >> KVM_REG_PPC_ICP_CPPR_SHIFT;
811 	xisr = (icpval >> KVM_REG_PPC_ICP_XISR_SHIFT) &
812 		KVM_REG_PPC_ICP_XISR_MASK;
813 	mfrr = icpval >> KVM_REG_PPC_ICP_MFRR_SHIFT;
814 
815 	pr_devel("set_icp vcpu %d cppr=0x%x mfrr=0x%x xisr=0x%x\n",
816 		 xc->server_num, cppr, mfrr, xisr);
817 
818 	/*
819 	 * We can't update the state of a "pushed" VCPU, but that
820 	 * shouldn't happen because the vcpu->mutex makes running a
821 	 * vcpu mutually exclusive with doing one_reg get/set on it.
822 	 */
823 	if (WARN_ON(vcpu->arch.xive_pushed))
824 		return -EIO;
825 
826 	/* Update VCPU HW saved state */
827 	vcpu->arch.xive_saved_state.cppr = cppr;
828 	xc->hw_cppr = xc->cppr = cppr;
829 
830 	/*
831 	 * Update MFRR state. If it's not 0xff, we mark the VCPU as
832 	 * having a pending MFRR change, which will re-evaluate the
833 	 * target. The VCPU will thus potentially get a spurious
834 	 * interrupt but that's not a big deal.
835 	 */
836 	xc->mfrr = mfrr;
837 	if (mfrr < cppr)
838 		xive_irq_trigger(&xc->vp_ipi_data);
839 
840 	/*
841 	 * Now saved XIRR is "interesting". It means there's something in
842 	 * the legacy "1 element" queue... for an IPI we simply ignore it,
843 	 * as the MFRR restore will handle that. For anything else we need
844 	 * to force a resend of the source.
845 	 * However the source may not have been setup yet. If that's the
846 	 * case, we keep that info and increment a counter in the xive to
847 	 * tell subsequent xive_set_source() to go look.
848 	 */
849 	if (xisr > XICS_IPI && !xive_restore_pending_irq(xive, xisr)) {
850 		xc->delayed_irq = xisr;
851 		xive->delayed_irqs++;
852 		pr_devel("  xisr restore delayed\n");
853 	}
854 
855 	return 0;
856 }
857 
858 int kvmppc_xive_set_mapped(struct kvm *kvm, unsigned long guest_irq,
859 			   struct irq_desc *host_desc)
860 {
861 	struct kvmppc_xive *xive = kvm->arch.xive;
862 	struct kvmppc_xive_src_block *sb;
863 	struct kvmppc_xive_irq_state *state;
864 	struct irq_data *host_data = irq_desc_get_irq_data(host_desc);
865 	unsigned int host_irq = irq_desc_get_irq(host_desc);
866 	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(host_data);
867 	u16 idx;
868 	u8 prio;
869 	int rc;
870 
871 	if (!xive)
872 		return -ENODEV;
873 
874 	pr_devel("set_mapped girq 0x%lx host HW irq 0x%x...\n",guest_irq, hw_irq);
875 
876 	sb = kvmppc_xive_find_source(xive, guest_irq, &idx);
877 	if (!sb)
878 		return -EINVAL;
879 	state = &sb->irq_state[idx];
880 
881 	/*
882 	 * Mark the passed-through interrupt as going to a VCPU,
883 	 * this will prevent further EOIs and similar operations
884 	 * from the XIVE code. It will also mask the interrupt
885 	 * to either PQ=10 or 11 state, the latter if the interrupt
886 	 * is pending. This will allow us to unmask or retrigger it
887 	 * after routing it to the guest with a simple EOI.
888 	 *
889 	 * The "state" argument is a "token", all it needs is to be
890 	 * non-NULL to switch to passed-through or NULL for the
891 	 * other way around. We may not yet have an actual VCPU
892 	 * target here and we don't really care.
893 	 */
894 	rc = irq_set_vcpu_affinity(host_irq, state);
895 	if (rc) {
896 		pr_err("Failed to set VCPU affinity for irq %d\n", host_irq);
897 		return rc;
898 	}
899 
900 	/*
901 	 * Mask and read state of IPI. We need to know if its P bit
902 	 * is set as that means it's potentially already using a
903 	 * queue entry in the target
904 	 */
905 	prio = xive_lock_and_mask(xive, sb, state);
906 	pr_devel(" old IPI prio %02x P:%d Q:%d\n", prio,
907 		 state->old_p, state->old_q);
908 
909 	/* Turn the IPI hard off */
910 	xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_01);
911 
912 	/*
913 	 * Reset ESB guest mapping. Needed when ESB pages are exposed
914 	 * to the guest in XIVE native mode
915 	 */
916 	if (xive->ops && xive->ops->reset_mapped)
917 		xive->ops->reset_mapped(kvm, guest_irq);
918 
919 	/* Grab info about irq */
920 	state->pt_number = hw_irq;
921 	state->pt_data = irq_data_get_irq_handler_data(host_data);
922 
923 	/*
924 	 * Configure the IRQ to match the existing configuration of
925 	 * the IPI if it was already targetted. Otherwise this will
926 	 * mask the interrupt in a lossy way (act_priority is 0xff)
927 	 * which is fine for a never started interrupt.
928 	 */
929 	xive_native_configure_irq(hw_irq,
930 				  kvmppc_xive_vp(xive, state->act_server),
931 				  state->act_priority, state->number);
932 
933 	/*
934 	 * We do an EOI to enable the interrupt (and retrigger if needed)
935 	 * if the guest has the interrupt unmasked and the P bit was *not*
936 	 * set in the IPI. If it was set, we know a slot may still be in
937 	 * use in the target queue thus we have to wait for a guest
938 	 * originated EOI
939 	 */
940 	if (prio != MASKED && !state->old_p)
941 		xive_vm_source_eoi(hw_irq, state->pt_data);
942 
943 	/* Clear old_p/old_q as they are no longer relevant */
944 	state->old_p = state->old_q = false;
945 
946 	/* Restore guest prio (unlocks EOI) */
947 	mb();
948 	state->guest_priority = prio;
949 	arch_spin_unlock(&sb->lock);
950 
951 	return 0;
952 }
953 EXPORT_SYMBOL_GPL(kvmppc_xive_set_mapped);
954 
955 int kvmppc_xive_clr_mapped(struct kvm *kvm, unsigned long guest_irq,
956 			   struct irq_desc *host_desc)
957 {
958 	struct kvmppc_xive *xive = kvm->arch.xive;
959 	struct kvmppc_xive_src_block *sb;
960 	struct kvmppc_xive_irq_state *state;
961 	unsigned int host_irq = irq_desc_get_irq(host_desc);
962 	u16 idx;
963 	u8 prio;
964 	int rc;
965 
966 	if (!xive)
967 		return -ENODEV;
968 
969 	pr_devel("clr_mapped girq 0x%lx...\n", guest_irq);
970 
971 	sb = kvmppc_xive_find_source(xive, guest_irq, &idx);
972 	if (!sb)
973 		return -EINVAL;
974 	state = &sb->irq_state[idx];
975 
976 	/*
977 	 * Mask and read state of IRQ. We need to know if its P bit
978 	 * is set as that means it's potentially already using a
979 	 * queue entry in the target
980 	 */
981 	prio = xive_lock_and_mask(xive, sb, state);
982 	pr_devel(" old IRQ prio %02x P:%d Q:%d\n", prio,
983 		 state->old_p, state->old_q);
984 
985 	/*
986 	 * If old_p is set, the interrupt is pending, we switch it to
987 	 * PQ=11. This will force a resend in the host so the interrupt
988 	 * isn't lost to whatver host driver may pick it up
989 	 */
990 	if (state->old_p)
991 		xive_vm_esb_load(state->pt_data, XIVE_ESB_SET_PQ_11);
992 
993 	/* Release the passed-through interrupt to the host */
994 	rc = irq_set_vcpu_affinity(host_irq, NULL);
995 	if (rc) {
996 		pr_err("Failed to clr VCPU affinity for irq %d\n", host_irq);
997 		return rc;
998 	}
999 
1000 	/* Forget about the IRQ */
1001 	state->pt_number = 0;
1002 	state->pt_data = NULL;
1003 
1004 	/*
1005 	 * Reset ESB guest mapping. Needed when ESB pages are exposed
1006 	 * to the guest in XIVE native mode
1007 	 */
1008 	if (xive->ops && xive->ops->reset_mapped) {
1009 		xive->ops->reset_mapped(kvm, guest_irq);
1010 	}
1011 
1012 	/* Reconfigure the IPI */
1013 	xive_native_configure_irq(state->ipi_number,
1014 				  kvmppc_xive_vp(xive, state->act_server),
1015 				  state->act_priority, state->number);
1016 
1017 	/*
1018 	 * If old_p is set (we have a queue entry potentially
1019 	 * occupied) or the interrupt is masked, we set the IPI
1020 	 * to PQ=10 state. Otherwise we just re-enable it (PQ=00).
1021 	 */
1022 	if (prio == MASKED || state->old_p)
1023 		xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_10);
1024 	else
1025 		xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_00);
1026 
1027 	/* Restore guest prio (unlocks EOI) */
1028 	mb();
1029 	state->guest_priority = prio;
1030 	arch_spin_unlock(&sb->lock);
1031 
1032 	return 0;
1033 }
1034 EXPORT_SYMBOL_GPL(kvmppc_xive_clr_mapped);
1035 
1036 void kvmppc_xive_disable_vcpu_interrupts(struct kvm_vcpu *vcpu)
1037 {
1038 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
1039 	struct kvm *kvm = vcpu->kvm;
1040 	struct kvmppc_xive *xive = kvm->arch.xive;
1041 	int i, j;
1042 
1043 	for (i = 0; i <= xive->max_sbid; i++) {
1044 		struct kvmppc_xive_src_block *sb = xive->src_blocks[i];
1045 
1046 		if (!sb)
1047 			continue;
1048 		for (j = 0; j < KVMPPC_XICS_IRQ_PER_ICS; j++) {
1049 			struct kvmppc_xive_irq_state *state = &sb->irq_state[j];
1050 
1051 			if (!state->valid)
1052 				continue;
1053 			if (state->act_priority == MASKED)
1054 				continue;
1055 			if (state->act_server != xc->server_num)
1056 				continue;
1057 
1058 			/* Clean it up */
1059 			arch_spin_lock(&sb->lock);
1060 			state->act_priority = MASKED;
1061 			xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_01);
1062 			xive_native_configure_irq(state->ipi_number, 0, MASKED, 0);
1063 			if (state->pt_number) {
1064 				xive_vm_esb_load(state->pt_data, XIVE_ESB_SET_PQ_01);
1065 				xive_native_configure_irq(state->pt_number, 0, MASKED, 0);
1066 			}
1067 			arch_spin_unlock(&sb->lock);
1068 		}
1069 	}
1070 
1071 	/* Disable vcpu's escalation interrupt */
1072 	if (vcpu->arch.xive_esc_on) {
1073 		__raw_readq((void __iomem *)(vcpu->arch.xive_esc_vaddr +
1074 					     XIVE_ESB_SET_PQ_01));
1075 		vcpu->arch.xive_esc_on = false;
1076 	}
1077 
1078 	/*
1079 	 * Clear pointers to escalation interrupt ESB.
1080 	 * This is safe because the vcpu->mutex is held, preventing
1081 	 * any other CPU from concurrently executing a KVM_RUN ioctl.
1082 	 */
1083 	vcpu->arch.xive_esc_vaddr = 0;
1084 	vcpu->arch.xive_esc_raddr = 0;
1085 }
1086 
1087 /*
1088  * In single escalation mode, the escalation interrupt is marked so
1089  * that EOI doesn't re-enable it, but just sets the stale_p flag to
1090  * indicate that the P bit has already been dealt with.  However, the
1091  * assembly code that enters the guest sets PQ to 00 without clearing
1092  * stale_p (because it has no easy way to address it).  Hence we have
1093  * to adjust stale_p before shutting down the interrupt.
1094  */
1095 void xive_cleanup_single_escalation(struct kvm_vcpu *vcpu,
1096 				    struct kvmppc_xive_vcpu *xc, int irq)
1097 {
1098 	struct irq_data *d = irq_get_irq_data(irq);
1099 	struct xive_irq_data *xd = irq_data_get_irq_handler_data(d);
1100 
1101 	/*
1102 	 * This slightly odd sequence gives the right result
1103 	 * (i.e. stale_p set if xive_esc_on is false) even if
1104 	 * we race with xive_esc_irq() and xive_irq_eoi().
1105 	 */
1106 	xd->stale_p = false;
1107 	smp_mb();		/* paired with smb_wmb in xive_esc_irq */
1108 	if (!vcpu->arch.xive_esc_on)
1109 		xd->stale_p = true;
1110 }
1111 
1112 void kvmppc_xive_cleanup_vcpu(struct kvm_vcpu *vcpu)
1113 {
1114 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
1115 	struct kvmppc_xive *xive = vcpu->kvm->arch.xive;
1116 	int i;
1117 
1118 	if (!kvmppc_xics_enabled(vcpu))
1119 		return;
1120 
1121 	if (!xc)
1122 		return;
1123 
1124 	pr_devel("cleanup_vcpu(cpu=%d)\n", xc->server_num);
1125 
1126 	/* Ensure no interrupt is still routed to that VP */
1127 	xc->valid = false;
1128 	kvmppc_xive_disable_vcpu_interrupts(vcpu);
1129 
1130 	/* Mask the VP IPI */
1131 	xive_vm_esb_load(&xc->vp_ipi_data, XIVE_ESB_SET_PQ_01);
1132 
1133 	/* Free escalations */
1134 	for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) {
1135 		if (xc->esc_virq[i]) {
1136 			if (xc->xive->single_escalation)
1137 				xive_cleanup_single_escalation(vcpu, xc,
1138 							xc->esc_virq[i]);
1139 			free_irq(xc->esc_virq[i], vcpu);
1140 			irq_dispose_mapping(xc->esc_virq[i]);
1141 			kfree(xc->esc_virq_names[i]);
1142 		}
1143 	}
1144 
1145 	/* Disable the VP */
1146 	xive_native_disable_vp(xc->vp_id);
1147 
1148 	/* Clear the cam word so guest entry won't try to push context */
1149 	vcpu->arch.xive_cam_word = 0;
1150 
1151 	/* Free the queues */
1152 	for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) {
1153 		struct xive_q *q = &xc->queues[i];
1154 
1155 		xive_native_disable_queue(xc->vp_id, q, i);
1156 		if (q->qpage) {
1157 			free_pages((unsigned long)q->qpage,
1158 				   xive->q_page_order);
1159 			q->qpage = NULL;
1160 		}
1161 	}
1162 
1163 	/* Free the IPI */
1164 	if (xc->vp_ipi) {
1165 		xive_cleanup_irq_data(&xc->vp_ipi_data);
1166 		xive_native_free_irq(xc->vp_ipi);
1167 	}
1168 	/* Free the VP */
1169 	kfree(xc);
1170 
1171 	/* Cleanup the vcpu */
1172 	vcpu->arch.irq_type = KVMPPC_IRQ_DEFAULT;
1173 	vcpu->arch.xive_vcpu = NULL;
1174 }
1175 
1176 static bool kvmppc_xive_vcpu_id_valid(struct kvmppc_xive *xive, u32 cpu)
1177 {
1178 	/* We have a block of xive->nr_servers VPs. We just need to check
1179 	 * packed vCPU ids are below that.
1180 	 */
1181 	return kvmppc_pack_vcpu_id(xive->kvm, cpu) < xive->nr_servers;
1182 }
1183 
1184 int kvmppc_xive_compute_vp_id(struct kvmppc_xive *xive, u32 cpu, u32 *vp)
1185 {
1186 	u32 vp_id;
1187 
1188 	if (!kvmppc_xive_vcpu_id_valid(xive, cpu)) {
1189 		pr_devel("Out of bounds !\n");
1190 		return -EINVAL;
1191 	}
1192 
1193 	if (xive->vp_base == XIVE_INVALID_VP) {
1194 		xive->vp_base = xive_native_alloc_vp_block(xive->nr_servers);
1195 		pr_devel("VP_Base=%x nr_servers=%d\n", xive->vp_base, xive->nr_servers);
1196 
1197 		if (xive->vp_base == XIVE_INVALID_VP)
1198 			return -ENOSPC;
1199 	}
1200 
1201 	vp_id = kvmppc_xive_vp(xive, cpu);
1202 	if (kvmppc_xive_vp_in_use(xive->kvm, vp_id)) {
1203 		pr_devel("Duplicate !\n");
1204 		return -EEXIST;
1205 	}
1206 
1207 	*vp = vp_id;
1208 
1209 	return 0;
1210 }
1211 
1212 int kvmppc_xive_connect_vcpu(struct kvm_device *dev,
1213 			     struct kvm_vcpu *vcpu, u32 cpu)
1214 {
1215 	struct kvmppc_xive *xive = dev->private;
1216 	struct kvmppc_xive_vcpu *xc;
1217 	int i, r = -EBUSY;
1218 	u32 vp_id;
1219 
1220 	pr_devel("connect_vcpu(cpu=%d)\n", cpu);
1221 
1222 	if (dev->ops != &kvm_xive_ops) {
1223 		pr_devel("Wrong ops !\n");
1224 		return -EPERM;
1225 	}
1226 	if (xive->kvm != vcpu->kvm)
1227 		return -EPERM;
1228 	if (vcpu->arch.irq_type != KVMPPC_IRQ_DEFAULT)
1229 		return -EBUSY;
1230 
1231 	/* We need to synchronize with queue provisioning */
1232 	mutex_lock(&xive->lock);
1233 
1234 	r = kvmppc_xive_compute_vp_id(xive, cpu, &vp_id);
1235 	if (r)
1236 		goto bail;
1237 
1238 	xc = kzalloc(sizeof(*xc), GFP_KERNEL);
1239 	if (!xc) {
1240 		r = -ENOMEM;
1241 		goto bail;
1242 	}
1243 
1244 	vcpu->arch.xive_vcpu = xc;
1245 	xc->xive = xive;
1246 	xc->vcpu = vcpu;
1247 	xc->server_num = cpu;
1248 	xc->vp_id = vp_id;
1249 	xc->mfrr = 0xff;
1250 	xc->valid = true;
1251 
1252 	r = xive_native_get_vp_info(xc->vp_id, &xc->vp_cam, &xc->vp_chip_id);
1253 	if (r)
1254 		goto bail;
1255 
1256 	/* Configure VCPU fields for use by assembly push/pull */
1257 	vcpu->arch.xive_saved_state.w01 = cpu_to_be64(0xff000000);
1258 	vcpu->arch.xive_cam_word = cpu_to_be32(xc->vp_cam | TM_QW1W2_VO);
1259 
1260 	/* Allocate IPI */
1261 	xc->vp_ipi = xive_native_alloc_irq();
1262 	if (!xc->vp_ipi) {
1263 		pr_err("Failed to allocate xive irq for VCPU IPI\n");
1264 		r = -EIO;
1265 		goto bail;
1266 	}
1267 	pr_devel(" IPI=0x%x\n", xc->vp_ipi);
1268 
1269 	r = xive_native_populate_irq_data(xc->vp_ipi, &xc->vp_ipi_data);
1270 	if (r)
1271 		goto bail;
1272 
1273 	/*
1274 	 * Enable the VP first as the single escalation mode will
1275 	 * affect escalation interrupts numbering
1276 	 */
1277 	r = xive_native_enable_vp(xc->vp_id, xive->single_escalation);
1278 	if (r) {
1279 		pr_err("Failed to enable VP in OPAL, err %d\n", r);
1280 		goto bail;
1281 	}
1282 
1283 	/*
1284 	 * Initialize queues. Initially we set them all for no queueing
1285 	 * and we enable escalation for queue 0 only which we'll use for
1286 	 * our mfrr change notifications. If the VCPU is hot-plugged, we
1287 	 * do handle provisioning however based on the existing "map"
1288 	 * of enabled queues.
1289 	 */
1290 	for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) {
1291 		struct xive_q *q = &xc->queues[i];
1292 
1293 		/* Single escalation, no queue 7 */
1294 		if (i == 7 && xive->single_escalation)
1295 			break;
1296 
1297 		/* Is queue already enabled ? Provision it */
1298 		if (xive->qmap & (1 << i)) {
1299 			r = xive_provision_queue(vcpu, i);
1300 			if (r == 0 && !xive->single_escalation)
1301 				kvmppc_xive_attach_escalation(
1302 					vcpu, i, xive->single_escalation);
1303 			if (r)
1304 				goto bail;
1305 		} else {
1306 			r = xive_native_configure_queue(xc->vp_id,
1307 							q, i, NULL, 0, true);
1308 			if (r) {
1309 				pr_err("Failed to configure queue %d for VCPU %d\n",
1310 				       i, cpu);
1311 				goto bail;
1312 			}
1313 		}
1314 	}
1315 
1316 	/* If not done above, attach priority 0 escalation */
1317 	r = kvmppc_xive_attach_escalation(vcpu, 0, xive->single_escalation);
1318 	if (r)
1319 		goto bail;
1320 
1321 	/* Route the IPI */
1322 	r = xive_native_configure_irq(xc->vp_ipi, xc->vp_id, 0, XICS_IPI);
1323 	if (!r)
1324 		xive_vm_esb_load(&xc->vp_ipi_data, XIVE_ESB_SET_PQ_00);
1325 
1326 bail:
1327 	mutex_unlock(&xive->lock);
1328 	if (r) {
1329 		kvmppc_xive_cleanup_vcpu(vcpu);
1330 		return r;
1331 	}
1332 
1333 	vcpu->arch.irq_type = KVMPPC_IRQ_XICS;
1334 	return 0;
1335 }
1336 
1337 /*
1338  * Scanning of queues before/after migration save
1339  */
1340 static void xive_pre_save_set_queued(struct kvmppc_xive *xive, u32 irq)
1341 {
1342 	struct kvmppc_xive_src_block *sb;
1343 	struct kvmppc_xive_irq_state *state;
1344 	u16 idx;
1345 
1346 	sb = kvmppc_xive_find_source(xive, irq, &idx);
1347 	if (!sb)
1348 		return;
1349 
1350 	state = &sb->irq_state[idx];
1351 
1352 	/* Some sanity checking */
1353 	if (!state->valid) {
1354 		pr_err("invalid irq 0x%x in cpu queue!\n", irq);
1355 		return;
1356 	}
1357 
1358 	/*
1359 	 * If the interrupt is in a queue it should have P set.
1360 	 * We warn so that gets reported. A backtrace isn't useful
1361 	 * so no need to use a WARN_ON.
1362 	 */
1363 	if (!state->saved_p)
1364 		pr_err("Interrupt 0x%x is marked in a queue but P not set !\n", irq);
1365 
1366 	/* Set flag */
1367 	state->in_queue = true;
1368 }
1369 
1370 static void xive_pre_save_mask_irq(struct kvmppc_xive *xive,
1371 				   struct kvmppc_xive_src_block *sb,
1372 				   u32 irq)
1373 {
1374 	struct kvmppc_xive_irq_state *state = &sb->irq_state[irq];
1375 
1376 	if (!state->valid)
1377 		return;
1378 
1379 	/* Mask and save state, this will also sync HW queues */
1380 	state->saved_scan_prio = xive_lock_and_mask(xive, sb, state);
1381 
1382 	/* Transfer P and Q */
1383 	state->saved_p = state->old_p;
1384 	state->saved_q = state->old_q;
1385 
1386 	/* Unlock */
1387 	arch_spin_unlock(&sb->lock);
1388 }
1389 
1390 static void xive_pre_save_unmask_irq(struct kvmppc_xive *xive,
1391 				     struct kvmppc_xive_src_block *sb,
1392 				     u32 irq)
1393 {
1394 	struct kvmppc_xive_irq_state *state = &sb->irq_state[irq];
1395 
1396 	if (!state->valid)
1397 		return;
1398 
1399 	/*
1400 	 * Lock / exclude EOI (not technically necessary if the
1401 	 * guest isn't running concurrently. If this becomes a
1402 	 * performance issue we can probably remove the lock.
1403 	 */
1404 	xive_lock_for_unmask(sb, state);
1405 
1406 	/* Restore mask/prio if it wasn't masked */
1407 	if (state->saved_scan_prio != MASKED)
1408 		xive_finish_unmask(xive, sb, state, state->saved_scan_prio);
1409 
1410 	/* Unlock */
1411 	arch_spin_unlock(&sb->lock);
1412 }
1413 
1414 static void xive_pre_save_queue(struct kvmppc_xive *xive, struct xive_q *q)
1415 {
1416 	u32 idx = q->idx;
1417 	u32 toggle = q->toggle;
1418 	u32 irq;
1419 
1420 	do {
1421 		irq = __xive_read_eq(q->qpage, q->msk, &idx, &toggle);
1422 		if (irq > XICS_IPI)
1423 			xive_pre_save_set_queued(xive, irq);
1424 	} while(irq);
1425 }
1426 
1427 static void xive_pre_save_scan(struct kvmppc_xive *xive)
1428 {
1429 	struct kvm_vcpu *vcpu = NULL;
1430 	int i, j;
1431 
1432 	/*
1433 	 * See comment in xive_get_source() about how this
1434 	 * work. Collect a stable state for all interrupts
1435 	 */
1436 	for (i = 0; i <= xive->max_sbid; i++) {
1437 		struct kvmppc_xive_src_block *sb = xive->src_blocks[i];
1438 		if (!sb)
1439 			continue;
1440 		for (j = 0;  j < KVMPPC_XICS_IRQ_PER_ICS; j++)
1441 			xive_pre_save_mask_irq(xive, sb, j);
1442 	}
1443 
1444 	/* Then scan the queues and update the "in_queue" flag */
1445 	kvm_for_each_vcpu(i, vcpu, xive->kvm) {
1446 		struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
1447 		if (!xc)
1448 			continue;
1449 		for (j = 0; j < KVMPPC_XIVE_Q_COUNT; j++) {
1450 			if (xc->queues[j].qpage)
1451 				xive_pre_save_queue(xive, &xc->queues[j]);
1452 		}
1453 	}
1454 
1455 	/* Finally restore interrupt states */
1456 	for (i = 0; i <= xive->max_sbid; i++) {
1457 		struct kvmppc_xive_src_block *sb = xive->src_blocks[i];
1458 		if (!sb)
1459 			continue;
1460 		for (j = 0;  j < KVMPPC_XICS_IRQ_PER_ICS; j++)
1461 			xive_pre_save_unmask_irq(xive, sb, j);
1462 	}
1463 }
1464 
1465 static void xive_post_save_scan(struct kvmppc_xive *xive)
1466 {
1467 	u32 i, j;
1468 
1469 	/* Clear all the in_queue flags */
1470 	for (i = 0; i <= xive->max_sbid; i++) {
1471 		struct kvmppc_xive_src_block *sb = xive->src_blocks[i];
1472 		if (!sb)
1473 			continue;
1474 		for (j = 0;  j < KVMPPC_XICS_IRQ_PER_ICS; j++)
1475 			sb->irq_state[j].in_queue = false;
1476 	}
1477 
1478 	/* Next get_source() will do a new scan */
1479 	xive->saved_src_count = 0;
1480 }
1481 
1482 /*
1483  * This returns the source configuration and state to user space.
1484  */
1485 static int xive_get_source(struct kvmppc_xive *xive, long irq, u64 addr)
1486 {
1487 	struct kvmppc_xive_src_block *sb;
1488 	struct kvmppc_xive_irq_state *state;
1489 	u64 __user *ubufp = (u64 __user *) addr;
1490 	u64 val, prio;
1491 	u16 idx;
1492 
1493 	sb = kvmppc_xive_find_source(xive, irq, &idx);
1494 	if (!sb)
1495 		return -ENOENT;
1496 
1497 	state = &sb->irq_state[idx];
1498 
1499 	if (!state->valid)
1500 		return -ENOENT;
1501 
1502 	pr_devel("get_source(%ld)...\n", irq);
1503 
1504 	/*
1505 	 * So to properly save the state into something that looks like a
1506 	 * XICS migration stream we cannot treat interrupts individually.
1507 	 *
1508 	 * We need, instead, mask them all (& save their previous PQ state)
1509 	 * to get a stable state in the HW, then sync them to ensure that
1510 	 * any interrupt that had already fired hits its queue, and finally
1511 	 * scan all the queues to collect which interrupts are still present
1512 	 * in the queues, so we can set the "pending" flag on them and
1513 	 * they can be resent on restore.
1514 	 *
1515 	 * So we do it all when the "first" interrupt gets saved, all the
1516 	 * state is collected at that point, the rest of xive_get_source()
1517 	 * will merely collect and convert that state to the expected
1518 	 * userspace bit mask.
1519 	 */
1520 	if (xive->saved_src_count == 0)
1521 		xive_pre_save_scan(xive);
1522 	xive->saved_src_count++;
1523 
1524 	/* Convert saved state into something compatible with xics */
1525 	val = state->act_server;
1526 	prio = state->saved_scan_prio;
1527 
1528 	if (prio == MASKED) {
1529 		val |= KVM_XICS_MASKED;
1530 		prio = state->saved_priority;
1531 	}
1532 	val |= prio << KVM_XICS_PRIORITY_SHIFT;
1533 	if (state->lsi) {
1534 		val |= KVM_XICS_LEVEL_SENSITIVE;
1535 		if (state->saved_p)
1536 			val |= KVM_XICS_PENDING;
1537 	} else {
1538 		if (state->saved_p)
1539 			val |= KVM_XICS_PRESENTED;
1540 
1541 		if (state->saved_q)
1542 			val |= KVM_XICS_QUEUED;
1543 
1544 		/*
1545 		 * We mark it pending (which will attempt a re-delivery)
1546 		 * if we are in a queue *or* we were masked and had
1547 		 * Q set which is equivalent to the XICS "masked pending"
1548 		 * state
1549 		 */
1550 		if (state->in_queue || (prio == MASKED && state->saved_q))
1551 			val |= KVM_XICS_PENDING;
1552 	}
1553 
1554 	/*
1555 	 * If that was the last interrupt saved, reset the
1556 	 * in_queue flags
1557 	 */
1558 	if (xive->saved_src_count == xive->src_count)
1559 		xive_post_save_scan(xive);
1560 
1561 	/* Copy the result to userspace */
1562 	if (put_user(val, ubufp))
1563 		return -EFAULT;
1564 
1565 	return 0;
1566 }
1567 
1568 struct kvmppc_xive_src_block *kvmppc_xive_create_src_block(
1569 	struct kvmppc_xive *xive, int irq)
1570 {
1571 	struct kvmppc_xive_src_block *sb;
1572 	int i, bid;
1573 
1574 	bid = irq >> KVMPPC_XICS_ICS_SHIFT;
1575 
1576 	mutex_lock(&xive->lock);
1577 
1578 	/* block already exists - somebody else got here first */
1579 	if (xive->src_blocks[bid])
1580 		goto out;
1581 
1582 	/* Create the ICS */
1583 	sb = kzalloc(sizeof(*sb), GFP_KERNEL);
1584 	if (!sb)
1585 		goto out;
1586 
1587 	sb->id = bid;
1588 
1589 	for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
1590 		sb->irq_state[i].number = (bid << KVMPPC_XICS_ICS_SHIFT) | i;
1591 		sb->irq_state[i].eisn = 0;
1592 		sb->irq_state[i].guest_priority = MASKED;
1593 		sb->irq_state[i].saved_priority = MASKED;
1594 		sb->irq_state[i].act_priority = MASKED;
1595 	}
1596 	smp_wmb();
1597 	xive->src_blocks[bid] = sb;
1598 
1599 	if (bid > xive->max_sbid)
1600 		xive->max_sbid = bid;
1601 
1602 out:
1603 	mutex_unlock(&xive->lock);
1604 	return xive->src_blocks[bid];
1605 }
1606 
1607 static bool xive_check_delayed_irq(struct kvmppc_xive *xive, u32 irq)
1608 {
1609 	struct kvm *kvm = xive->kvm;
1610 	struct kvm_vcpu *vcpu = NULL;
1611 	int i;
1612 
1613 	kvm_for_each_vcpu(i, vcpu, kvm) {
1614 		struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
1615 
1616 		if (!xc)
1617 			continue;
1618 
1619 		if (xc->delayed_irq == irq) {
1620 			xc->delayed_irq = 0;
1621 			xive->delayed_irqs--;
1622 			return true;
1623 		}
1624 	}
1625 	return false;
1626 }
1627 
1628 static int xive_set_source(struct kvmppc_xive *xive, long irq, u64 addr)
1629 {
1630 	struct kvmppc_xive_src_block *sb;
1631 	struct kvmppc_xive_irq_state *state;
1632 	u64 __user *ubufp = (u64 __user *) addr;
1633 	u16 idx;
1634 	u64 val;
1635 	u8 act_prio, guest_prio;
1636 	u32 server;
1637 	int rc = 0;
1638 
1639 	if (irq < KVMPPC_XICS_FIRST_IRQ || irq >= KVMPPC_XICS_NR_IRQS)
1640 		return -ENOENT;
1641 
1642 	pr_devel("set_source(irq=0x%lx)\n", irq);
1643 
1644 	/* Find the source */
1645 	sb = kvmppc_xive_find_source(xive, irq, &idx);
1646 	if (!sb) {
1647 		pr_devel("No source, creating source block...\n");
1648 		sb = kvmppc_xive_create_src_block(xive, irq);
1649 		if (!sb) {
1650 			pr_devel("Failed to create block...\n");
1651 			return -ENOMEM;
1652 		}
1653 	}
1654 	state = &sb->irq_state[idx];
1655 
1656 	/* Read user passed data */
1657 	if (get_user(val, ubufp)) {
1658 		pr_devel("fault getting user info !\n");
1659 		return -EFAULT;
1660 	}
1661 
1662 	server = val & KVM_XICS_DESTINATION_MASK;
1663 	guest_prio = val >> KVM_XICS_PRIORITY_SHIFT;
1664 
1665 	pr_devel("  val=0x016%llx (server=0x%x, guest_prio=%d)\n",
1666 		 val, server, guest_prio);
1667 
1668 	/*
1669 	 * If the source doesn't already have an IPI, allocate
1670 	 * one and get the corresponding data
1671 	 */
1672 	if (!state->ipi_number) {
1673 		state->ipi_number = xive_native_alloc_irq();
1674 		if (state->ipi_number == 0) {
1675 			pr_devel("Failed to allocate IPI !\n");
1676 			return -ENOMEM;
1677 		}
1678 		xive_native_populate_irq_data(state->ipi_number, &state->ipi_data);
1679 		pr_devel(" src_ipi=0x%x\n", state->ipi_number);
1680 	}
1681 
1682 	/*
1683 	 * We use lock_and_mask() to set us in the right masked
1684 	 * state. We will override that state from the saved state
1685 	 * further down, but this will handle the cases of interrupts
1686 	 * that need FW masking. We set the initial guest_priority to
1687 	 * 0 before calling it to ensure it actually performs the masking.
1688 	 */
1689 	state->guest_priority = 0;
1690 	xive_lock_and_mask(xive, sb, state);
1691 
1692 	/*
1693 	 * Now, we select a target if we have one. If we don't we
1694 	 * leave the interrupt untargetted. It means that an interrupt
1695 	 * can become "untargetted" accross migration if it was masked
1696 	 * by set_xive() but there is little we can do about it.
1697 	 */
1698 
1699 	/* First convert prio and mark interrupt as untargetted */
1700 	act_prio = xive_prio_from_guest(guest_prio);
1701 	state->act_priority = MASKED;
1702 
1703 	/*
1704 	 * We need to drop the lock due to the mutex below. Hopefully
1705 	 * nothing is touching that interrupt yet since it hasn't been
1706 	 * advertized to a running guest yet
1707 	 */
1708 	arch_spin_unlock(&sb->lock);
1709 
1710 	/* If we have a priority target the interrupt */
1711 	if (act_prio != MASKED) {
1712 		/* First, check provisioning of queues */
1713 		mutex_lock(&xive->lock);
1714 		rc = xive_check_provisioning(xive->kvm, act_prio);
1715 		mutex_unlock(&xive->lock);
1716 
1717 		/* Target interrupt */
1718 		if (rc == 0)
1719 			rc = xive_target_interrupt(xive->kvm, state,
1720 						   server, act_prio);
1721 		/*
1722 		 * If provisioning or targetting failed, leave it
1723 		 * alone and masked. It will remain disabled until
1724 		 * the guest re-targets it.
1725 		 */
1726 	}
1727 
1728 	/*
1729 	 * Find out if this was a delayed irq stashed in an ICP,
1730 	 * in which case, treat it as pending
1731 	 */
1732 	if (xive->delayed_irqs && xive_check_delayed_irq(xive, irq)) {
1733 		val |= KVM_XICS_PENDING;
1734 		pr_devel("  Found delayed ! forcing PENDING !\n");
1735 	}
1736 
1737 	/* Cleanup the SW state */
1738 	state->old_p = false;
1739 	state->old_q = false;
1740 	state->lsi = false;
1741 	state->asserted = false;
1742 
1743 	/* Restore LSI state */
1744 	if (val & KVM_XICS_LEVEL_SENSITIVE) {
1745 		state->lsi = true;
1746 		if (val & KVM_XICS_PENDING)
1747 			state->asserted = true;
1748 		pr_devel("  LSI ! Asserted=%d\n", state->asserted);
1749 	}
1750 
1751 	/*
1752 	 * Restore P and Q. If the interrupt was pending, we
1753 	 * force Q and !P, which will trigger a resend.
1754 	 *
1755 	 * That means that a guest that had both an interrupt
1756 	 * pending (queued) and Q set will restore with only
1757 	 * one instance of that interrupt instead of 2, but that
1758 	 * is perfectly fine as coalescing interrupts that haven't
1759 	 * been presented yet is always allowed.
1760 	 */
1761 	if (val & KVM_XICS_PRESENTED && !(val & KVM_XICS_PENDING))
1762 		state->old_p = true;
1763 	if (val & KVM_XICS_QUEUED || val & KVM_XICS_PENDING)
1764 		state->old_q = true;
1765 
1766 	pr_devel("  P=%d, Q=%d\n", state->old_p, state->old_q);
1767 
1768 	/*
1769 	 * If the interrupt was unmasked, update guest priority and
1770 	 * perform the appropriate state transition and do a
1771 	 * re-trigger if necessary.
1772 	 */
1773 	if (val & KVM_XICS_MASKED) {
1774 		pr_devel("  masked, saving prio\n");
1775 		state->guest_priority = MASKED;
1776 		state->saved_priority = guest_prio;
1777 	} else {
1778 		pr_devel("  unmasked, restoring to prio %d\n", guest_prio);
1779 		xive_finish_unmask(xive, sb, state, guest_prio);
1780 		state->saved_priority = guest_prio;
1781 	}
1782 
1783 	/* Increment the number of valid sources and mark this one valid */
1784 	if (!state->valid)
1785 		xive->src_count++;
1786 	state->valid = true;
1787 
1788 	return 0;
1789 }
1790 
1791 int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level,
1792 			bool line_status)
1793 {
1794 	struct kvmppc_xive *xive = kvm->arch.xive;
1795 	struct kvmppc_xive_src_block *sb;
1796 	struct kvmppc_xive_irq_state *state;
1797 	u16 idx;
1798 
1799 	if (!xive)
1800 		return -ENODEV;
1801 
1802 	sb = kvmppc_xive_find_source(xive, irq, &idx);
1803 	if (!sb)
1804 		return -EINVAL;
1805 
1806 	/* Perform locklessly .... (we need to do some RCUisms here...) */
1807 	state = &sb->irq_state[idx];
1808 	if (!state->valid)
1809 		return -EINVAL;
1810 
1811 	/* We don't allow a trigger on a passed-through interrupt */
1812 	if (state->pt_number)
1813 		return -EINVAL;
1814 
1815 	if ((level == 1 && state->lsi) || level == KVM_INTERRUPT_SET_LEVEL)
1816 		state->asserted = 1;
1817 	else if (level == 0 || level == KVM_INTERRUPT_UNSET) {
1818 		state->asserted = 0;
1819 		return 0;
1820 	}
1821 
1822 	/* Trigger the IPI */
1823 	xive_irq_trigger(&state->ipi_data);
1824 
1825 	return 0;
1826 }
1827 
1828 int kvmppc_xive_set_nr_servers(struct kvmppc_xive *xive, u64 addr)
1829 {
1830 	u32 __user *ubufp = (u32 __user *) addr;
1831 	u32 nr_servers;
1832 	int rc = 0;
1833 
1834 	if (get_user(nr_servers, ubufp))
1835 		return -EFAULT;
1836 
1837 	pr_devel("%s nr_servers=%u\n", __func__, nr_servers);
1838 
1839 	if (!nr_servers || nr_servers > KVM_MAX_VCPU_ID)
1840 		return -EINVAL;
1841 
1842 	mutex_lock(&xive->lock);
1843 	if (xive->vp_base != XIVE_INVALID_VP)
1844 		/* The VP block is allocated once and freed when the device
1845 		 * is released. Better not allow to change its size since its
1846 		 * used by connect_vcpu to validate vCPU ids are valid (eg,
1847 		 * setting it back to a higher value could allow connect_vcpu
1848 		 * to come up with a VP id that goes beyond the VP block, which
1849 		 * is likely to cause a crash in OPAL).
1850 		 */
1851 		rc = -EBUSY;
1852 	else if (nr_servers > KVM_MAX_VCPUS)
1853 		/* We don't need more servers. Higher vCPU ids get packed
1854 		 * down below KVM_MAX_VCPUS by kvmppc_pack_vcpu_id().
1855 		 */
1856 		xive->nr_servers = KVM_MAX_VCPUS;
1857 	else
1858 		xive->nr_servers = nr_servers;
1859 
1860 	mutex_unlock(&xive->lock);
1861 
1862 	return rc;
1863 }
1864 
1865 static int xive_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
1866 {
1867 	struct kvmppc_xive *xive = dev->private;
1868 
1869 	/* We honor the existing XICS ioctl */
1870 	switch (attr->group) {
1871 	case KVM_DEV_XICS_GRP_SOURCES:
1872 		return xive_set_source(xive, attr->attr, attr->addr);
1873 	case KVM_DEV_XICS_GRP_CTRL:
1874 		switch (attr->attr) {
1875 		case KVM_DEV_XICS_NR_SERVERS:
1876 			return kvmppc_xive_set_nr_servers(xive, attr->addr);
1877 		}
1878 	}
1879 	return -ENXIO;
1880 }
1881 
1882 static int xive_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
1883 {
1884 	struct kvmppc_xive *xive = dev->private;
1885 
1886 	/* We honor the existing XICS ioctl */
1887 	switch (attr->group) {
1888 	case KVM_DEV_XICS_GRP_SOURCES:
1889 		return xive_get_source(xive, attr->attr, attr->addr);
1890 	}
1891 	return -ENXIO;
1892 }
1893 
1894 static int xive_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
1895 {
1896 	/* We honor the same limits as XICS, at least for now */
1897 	switch (attr->group) {
1898 	case KVM_DEV_XICS_GRP_SOURCES:
1899 		if (attr->attr >= KVMPPC_XICS_FIRST_IRQ &&
1900 		    attr->attr < KVMPPC_XICS_NR_IRQS)
1901 			return 0;
1902 		break;
1903 	case KVM_DEV_XICS_GRP_CTRL:
1904 		switch (attr->attr) {
1905 		case KVM_DEV_XICS_NR_SERVERS:
1906 			return 0;
1907 		}
1908 	}
1909 	return -ENXIO;
1910 }
1911 
1912 static void kvmppc_xive_cleanup_irq(u32 hw_num, struct xive_irq_data *xd)
1913 {
1914 	xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_01);
1915 	xive_native_configure_irq(hw_num, 0, MASKED, 0);
1916 }
1917 
1918 void kvmppc_xive_free_sources(struct kvmppc_xive_src_block *sb)
1919 {
1920 	int i;
1921 
1922 	for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
1923 		struct kvmppc_xive_irq_state *state = &sb->irq_state[i];
1924 
1925 		if (!state->valid)
1926 			continue;
1927 
1928 		kvmppc_xive_cleanup_irq(state->ipi_number, &state->ipi_data);
1929 		xive_cleanup_irq_data(&state->ipi_data);
1930 		xive_native_free_irq(state->ipi_number);
1931 
1932 		/* Pass-through, cleanup too but keep IRQ hw data */
1933 		if (state->pt_number)
1934 			kvmppc_xive_cleanup_irq(state->pt_number, state->pt_data);
1935 
1936 		state->valid = false;
1937 	}
1938 }
1939 
1940 /*
1941  * Called when device fd is closed.  kvm->lock is held.
1942  */
1943 static void kvmppc_xive_release(struct kvm_device *dev)
1944 {
1945 	struct kvmppc_xive *xive = dev->private;
1946 	struct kvm *kvm = xive->kvm;
1947 	struct kvm_vcpu *vcpu;
1948 	int i;
1949 
1950 	pr_devel("Releasing xive device\n");
1951 
1952 	/*
1953 	 * Since this is the device release function, we know that
1954 	 * userspace does not have any open fd referring to the
1955 	 * device.  Therefore there can not be any of the device
1956 	 * attribute set/get functions being executed concurrently,
1957 	 * and similarly, the connect_vcpu and set/clr_mapped
1958 	 * functions also cannot be being executed.
1959 	 */
1960 
1961 	debugfs_remove(xive->dentry);
1962 
1963 	/*
1964 	 * We should clean up the vCPU interrupt presenters first.
1965 	 */
1966 	kvm_for_each_vcpu(i, vcpu, kvm) {
1967 		/*
1968 		 * Take vcpu->mutex to ensure that no one_reg get/set ioctl
1969 		 * (i.e. kvmppc_xive_[gs]et_icp) can be done concurrently.
1970 		 * Holding the vcpu->mutex also means that the vcpu cannot
1971 		 * be executing the KVM_RUN ioctl, and therefore it cannot
1972 		 * be executing the XIVE push or pull code or accessing
1973 		 * the XIVE MMIO regions.
1974 		 */
1975 		mutex_lock(&vcpu->mutex);
1976 		kvmppc_xive_cleanup_vcpu(vcpu);
1977 		mutex_unlock(&vcpu->mutex);
1978 	}
1979 
1980 	/*
1981 	 * Now that we have cleared vcpu->arch.xive_vcpu, vcpu->arch.irq_type
1982 	 * and vcpu->arch.xive_esc_[vr]addr on each vcpu, we are safe
1983 	 * against xive code getting called during vcpu execution or
1984 	 * set/get one_reg operations.
1985 	 */
1986 	kvm->arch.xive = NULL;
1987 
1988 	/* Mask and free interrupts */
1989 	for (i = 0; i <= xive->max_sbid; i++) {
1990 		if (xive->src_blocks[i])
1991 			kvmppc_xive_free_sources(xive->src_blocks[i]);
1992 		kfree(xive->src_blocks[i]);
1993 		xive->src_blocks[i] = NULL;
1994 	}
1995 
1996 	if (xive->vp_base != XIVE_INVALID_VP)
1997 		xive_native_free_vp_block(xive->vp_base);
1998 
1999 	/*
2000 	 * A reference of the kvmppc_xive pointer is now kept under
2001 	 * the xive_devices struct of the machine for reuse. It is
2002 	 * freed when the VM is destroyed for now until we fix all the
2003 	 * execution paths.
2004 	 */
2005 
2006 	kfree(dev);
2007 }
2008 
2009 /*
2010  * When the guest chooses the interrupt mode (XICS legacy or XIVE
2011  * native), the VM will switch of KVM device. The previous device will
2012  * be "released" before the new one is created.
2013  *
2014  * Until we are sure all execution paths are well protected, provide a
2015  * fail safe (transitional) method for device destruction, in which
2016  * the XIVE device pointer is recycled and not directly freed.
2017  */
2018 struct kvmppc_xive *kvmppc_xive_get_device(struct kvm *kvm, u32 type)
2019 {
2020 	struct kvmppc_xive **kvm_xive_device = type == KVM_DEV_TYPE_XIVE ?
2021 		&kvm->arch.xive_devices.native :
2022 		&kvm->arch.xive_devices.xics_on_xive;
2023 	struct kvmppc_xive *xive = *kvm_xive_device;
2024 
2025 	if (!xive) {
2026 		xive = kzalloc(sizeof(*xive), GFP_KERNEL);
2027 		*kvm_xive_device = xive;
2028 	} else {
2029 		memset(xive, 0, sizeof(*xive));
2030 	}
2031 
2032 	return xive;
2033 }
2034 
2035 /*
2036  * Create a XICS device with XIVE backend.  kvm->lock is held.
2037  */
2038 static int kvmppc_xive_create(struct kvm_device *dev, u32 type)
2039 {
2040 	struct kvmppc_xive *xive;
2041 	struct kvm *kvm = dev->kvm;
2042 
2043 	pr_devel("Creating xive for partition\n");
2044 
2045 	/* Already there ? */
2046 	if (kvm->arch.xive)
2047 		return -EEXIST;
2048 
2049 	xive = kvmppc_xive_get_device(kvm, type);
2050 	if (!xive)
2051 		return -ENOMEM;
2052 
2053 	dev->private = xive;
2054 	xive->dev = dev;
2055 	xive->kvm = kvm;
2056 	mutex_init(&xive->lock);
2057 
2058 	/* We use the default queue size set by the host */
2059 	xive->q_order = xive_native_default_eq_shift();
2060 	if (xive->q_order < PAGE_SHIFT)
2061 		xive->q_page_order = 0;
2062 	else
2063 		xive->q_page_order = xive->q_order - PAGE_SHIFT;
2064 
2065 	/* VP allocation is delayed to the first call to connect_vcpu */
2066 	xive->vp_base = XIVE_INVALID_VP;
2067 	/* KVM_MAX_VCPUS limits the number of VMs to roughly 64 per sockets
2068 	 * on a POWER9 system.
2069 	 */
2070 	xive->nr_servers = KVM_MAX_VCPUS;
2071 
2072 	xive->single_escalation = xive_native_has_single_escalation();
2073 
2074 	kvm->arch.xive = xive;
2075 	return 0;
2076 }
2077 
2078 int kvmppc_xive_debug_show_queues(struct seq_file *m, struct kvm_vcpu *vcpu)
2079 {
2080 	struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
2081 	unsigned int i;
2082 
2083 	for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) {
2084 		struct xive_q *q = &xc->queues[i];
2085 		u32 i0, i1, idx;
2086 
2087 		if (!q->qpage && !xc->esc_virq[i])
2088 			continue;
2089 
2090 		if (q->qpage) {
2091 			seq_printf(m, "    q[%d]: ", i);
2092 			idx = q->idx;
2093 			i0 = be32_to_cpup(q->qpage + idx);
2094 			idx = (idx + 1) & q->msk;
2095 			i1 = be32_to_cpup(q->qpage + idx);
2096 			seq_printf(m, "T=%d %08x %08x...\n", q->toggle,
2097 				   i0, i1);
2098 		}
2099 		if (xc->esc_virq[i]) {
2100 			struct irq_data *d = irq_get_irq_data(xc->esc_virq[i]);
2101 			struct xive_irq_data *xd =
2102 				irq_data_get_irq_handler_data(d);
2103 			u64 pq = xive_vm_esb_load(xd, XIVE_ESB_GET);
2104 
2105 			seq_printf(m, "    ESC %d %c%c EOI @%llx",
2106 				   xc->esc_virq[i],
2107 				   (pq & XIVE_ESB_VAL_P) ? 'P' : '-',
2108 				   (pq & XIVE_ESB_VAL_Q) ? 'Q' : '-',
2109 				   xd->eoi_page);
2110 			seq_puts(m, "\n");
2111 		}
2112 	}
2113 	return 0;
2114 }
2115 
2116 void kvmppc_xive_debug_show_sources(struct seq_file *m,
2117 				    struct kvmppc_xive_src_block *sb)
2118 {
2119 	int i;
2120 
2121 	seq_puts(m, "    LISN      HW/CHIP   TYPE    PQ      EISN    CPU/PRIO\n");
2122 	for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
2123 		struct kvmppc_xive_irq_state *state = &sb->irq_state[i];
2124 		struct xive_irq_data *xd;
2125 		u64 pq;
2126 		u32 hw_num;
2127 
2128 		if (!state->valid)
2129 			continue;
2130 
2131 		kvmppc_xive_select_irq(state, &hw_num, &xd);
2132 
2133 		pq = xive_vm_esb_load(xd, XIVE_ESB_GET);
2134 
2135 		seq_printf(m, "%08x  %08x/%02x", state->number, hw_num,
2136 			   xd->src_chip);
2137 		if (state->lsi)
2138 			seq_printf(m, " %cLSI", state->asserted ? '^' : ' ');
2139 		else
2140 			seq_puts(m, "  MSI");
2141 
2142 		seq_printf(m, " %s  %c%c  %08x   % 4d/%d",
2143 			   state->ipi_number == hw_num ? "IPI" : " PT",
2144 			   pq & XIVE_ESB_VAL_P ? 'P' : '-',
2145 			   pq & XIVE_ESB_VAL_Q ? 'Q' : '-',
2146 			   state->eisn, state->act_server,
2147 			   state->act_priority);
2148 
2149 		seq_puts(m, "\n");
2150 	}
2151 }
2152 
2153 static int xive_debug_show(struct seq_file *m, void *private)
2154 {
2155 	struct kvmppc_xive *xive = m->private;
2156 	struct kvm *kvm = xive->kvm;
2157 	struct kvm_vcpu *vcpu;
2158 	u64 t_rm_h_xirr = 0;
2159 	u64 t_rm_h_ipoll = 0;
2160 	u64 t_rm_h_cppr = 0;
2161 	u64 t_rm_h_eoi = 0;
2162 	u64 t_rm_h_ipi = 0;
2163 	u64 t_vm_h_xirr = 0;
2164 	u64 t_vm_h_ipoll = 0;
2165 	u64 t_vm_h_cppr = 0;
2166 	u64 t_vm_h_eoi = 0;
2167 	u64 t_vm_h_ipi = 0;
2168 	unsigned int i;
2169 
2170 	if (!kvm)
2171 		return 0;
2172 
2173 	seq_puts(m, "=========\nVCPU state\n=========\n");
2174 
2175 	kvm_for_each_vcpu(i, vcpu, kvm) {
2176 		struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu;
2177 
2178 		if (!xc)
2179 			continue;
2180 
2181 		seq_printf(m, "VCPU %d: VP:%#x/%02x\n"
2182 			 "    CPPR:%#x HWCPPR:%#x MFRR:%#x PEND:%#x h_xirr: R=%lld V=%lld\n",
2183 			 xc->server_num, xc->vp_id, xc->vp_chip_id,
2184 			 xc->cppr, xc->hw_cppr,
2185 			 xc->mfrr, xc->pending,
2186 			 xc->stat_rm_h_xirr, xc->stat_vm_h_xirr);
2187 
2188 		kvmppc_xive_debug_show_queues(m, vcpu);
2189 
2190 		t_rm_h_xirr += xc->stat_rm_h_xirr;
2191 		t_rm_h_ipoll += xc->stat_rm_h_ipoll;
2192 		t_rm_h_cppr += xc->stat_rm_h_cppr;
2193 		t_rm_h_eoi += xc->stat_rm_h_eoi;
2194 		t_rm_h_ipi += xc->stat_rm_h_ipi;
2195 		t_vm_h_xirr += xc->stat_vm_h_xirr;
2196 		t_vm_h_ipoll += xc->stat_vm_h_ipoll;
2197 		t_vm_h_cppr += xc->stat_vm_h_cppr;
2198 		t_vm_h_eoi += xc->stat_vm_h_eoi;
2199 		t_vm_h_ipi += xc->stat_vm_h_ipi;
2200 	}
2201 
2202 	seq_puts(m, "Hcalls totals\n");
2203 	seq_printf(m, " H_XIRR  R=%10lld V=%10lld\n", t_rm_h_xirr, t_vm_h_xirr);
2204 	seq_printf(m, " H_IPOLL R=%10lld V=%10lld\n", t_rm_h_ipoll, t_vm_h_ipoll);
2205 	seq_printf(m, " H_CPPR  R=%10lld V=%10lld\n", t_rm_h_cppr, t_vm_h_cppr);
2206 	seq_printf(m, " H_EOI   R=%10lld V=%10lld\n", t_rm_h_eoi, t_vm_h_eoi);
2207 	seq_printf(m, " H_IPI   R=%10lld V=%10lld\n", t_rm_h_ipi, t_vm_h_ipi);
2208 
2209 	seq_puts(m, "=========\nSources\n=========\n");
2210 
2211 	for (i = 0; i <= xive->max_sbid; i++) {
2212 		struct kvmppc_xive_src_block *sb = xive->src_blocks[i];
2213 
2214 		if (sb) {
2215 			arch_spin_lock(&sb->lock);
2216 			kvmppc_xive_debug_show_sources(m, sb);
2217 			arch_spin_unlock(&sb->lock);
2218 		}
2219 	}
2220 
2221 	return 0;
2222 }
2223 
2224 DEFINE_SHOW_ATTRIBUTE(xive_debug);
2225 
2226 static void xive_debugfs_init(struct kvmppc_xive *xive)
2227 {
2228 	char *name;
2229 
2230 	name = kasprintf(GFP_KERNEL, "kvm-xive-%p", xive);
2231 	if (!name) {
2232 		pr_err("%s: no memory for name\n", __func__);
2233 		return;
2234 	}
2235 
2236 	xive->dentry = debugfs_create_file(name, S_IRUGO, powerpc_debugfs_root,
2237 					   xive, &xive_debug_fops);
2238 
2239 	pr_debug("%s: created %s\n", __func__, name);
2240 	kfree(name);
2241 }
2242 
2243 static void kvmppc_xive_init(struct kvm_device *dev)
2244 {
2245 	struct kvmppc_xive *xive = (struct kvmppc_xive *)dev->private;
2246 
2247 	/* Register some debug interfaces */
2248 	xive_debugfs_init(xive);
2249 }
2250 
2251 struct kvm_device_ops kvm_xive_ops = {
2252 	.name = "kvm-xive",
2253 	.create = kvmppc_xive_create,
2254 	.init = kvmppc_xive_init,
2255 	.release = kvmppc_xive_release,
2256 	.set_attr = xive_set_attr,
2257 	.get_attr = xive_get_attr,
2258 	.has_attr = xive_has_attr,
2259 };
2260 
2261 void kvmppc_xive_init_module(void)
2262 {
2263 	__xive_vm_h_xirr = xive_vm_h_xirr;
2264 	__xive_vm_h_ipoll = xive_vm_h_ipoll;
2265 	__xive_vm_h_ipi = xive_vm_h_ipi;
2266 	__xive_vm_h_cppr = xive_vm_h_cppr;
2267 	__xive_vm_h_eoi = xive_vm_h_eoi;
2268 }
2269 
2270 void kvmppc_xive_exit_module(void)
2271 {
2272 	__xive_vm_h_xirr = NULL;
2273 	__xive_vm_h_ipoll = NULL;
2274 	__xive_vm_h_ipi = NULL;
2275 	__xive_vm_h_cppr = NULL;
2276 	__xive_vm_h_eoi = NULL;
2277 }
2278