1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2016 Linaro
4 * Author: Christoffer Dall <christoffer.dall@linaro.org>
5 */
6
7 #include <linux/cpu.h>
8 #include <linux/debugfs.h>
9 #include <linux/interrupt.h>
10 #include <linux/kvm_host.h>
11 #include <linux/seq_file.h>
12 #include <kvm/arm_vgic.h>
13 #include <asm/kvm_mmu.h>
14 #include "vgic.h"
15
16 /*
17 * Structure to control looping through the entire vgic state. We start at
18 * zero for each field and move upwards. So, if dist_id is 0 we print the
19 * distributor info. When dist_id is 1, we have already printed it and move
20 * on.
21 *
22 * When vcpu_id < nr_cpus we print the vcpu info until vcpu_id == nr_cpus and
23 * so on.
24 */
25 struct vgic_state_iter {
26 int nr_cpus;
27 int nr_spis;
28 int nr_lpis;
29 int dist_id;
30 int vcpu_id;
31 unsigned long intid;
32 int lpi_idx;
33 };
34
35 static void iter_next(struct kvm *kvm, struct vgic_state_iter *iter)
36 {
37 struct vgic_dist *dist = &kvm->arch.vgic;
38
39 if (iter->dist_id == 0) {
40 iter->dist_id++;
41 return;
42 }
43
44 /*
45 * Let the xarray drive the iterator after the last SPI, as the iterator
46 * has exhausted the sequentially-allocated INTID space.
47 */
48 if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS - 1) &&
49 iter->nr_lpis) {
50 if (iter->lpi_idx < iter->nr_lpis)
51 xa_find_after(&dist->lpi_xa, &iter->intid,
52 VGIC_LPI_MAX_INTID,
53 LPI_XA_MARK_DEBUG_ITER);
54 iter->lpi_idx++;
55 return;
56 }
57
58 iter->intid++;
59 if (iter->intid == VGIC_NR_PRIVATE_IRQS &&
60 ++iter->vcpu_id < iter->nr_cpus)
61 iter->intid = 0;
62 }
63
64 static int iter_mark_lpis(struct kvm *kvm)
65 {
66 struct vgic_dist *dist = &kvm->arch.vgic;
67 struct vgic_irq *irq;
68 unsigned long intid;
69 int nr_lpis = 0;
70
71 xa_for_each(&dist->lpi_xa, intid, irq) {
72 if (!vgic_try_get_irq_kref(irq))
73 continue;
74
75 xa_set_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
76 nr_lpis++;
77 }
78
79 return nr_lpis;
80 }
81
82 static void iter_unmark_lpis(struct kvm *kvm)
83 {
84 struct vgic_dist *dist = &kvm->arch.vgic;
85 struct vgic_irq *irq;
86 unsigned long intid;
87
88 xa_for_each_marked(&dist->lpi_xa, intid, irq, LPI_XA_MARK_DEBUG_ITER) {
89 xa_clear_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
90 vgic_put_irq(kvm, irq);
91 }
92 }
93
94 static void iter_init(struct kvm *kvm, struct vgic_state_iter *iter,
95 loff_t pos)
96 {
97 int nr_cpus = atomic_read(&kvm->online_vcpus);
98
99 memset(iter, 0, sizeof(*iter));
100
101 iter->nr_cpus = nr_cpus;
102 iter->nr_spis = kvm->arch.vgic.nr_spis;
103 if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
104 iter->nr_lpis = iter_mark_lpis(kvm);
105
106 /* Fast forward to the right position if needed */
107 while (pos--)
108 iter_next(kvm, iter);
109 }
110
111 static bool end_of_vgic(struct vgic_state_iter *iter)
112 {
113 return iter->dist_id > 0 &&
114 iter->vcpu_id == iter->nr_cpus &&
115 iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS) &&
116 (!iter->nr_lpis || iter->lpi_idx > iter->nr_lpis);
117 }
118
119 static void *vgic_debug_start(struct seq_file *s, loff_t *pos)
120 {
121 struct kvm *kvm = s->private;
122 struct vgic_state_iter *iter;
123
124 mutex_lock(&kvm->arch.config_lock);
125 iter = kvm->arch.vgic.iter;
126 if (iter) {
127 iter = ERR_PTR(-EBUSY);
128 goto out;
129 }
130
131 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
132 if (!iter) {
133 iter = ERR_PTR(-ENOMEM);
134 goto out;
135 }
136
137 iter_init(kvm, iter, *pos);
138 kvm->arch.vgic.iter = iter;
139
140 if (end_of_vgic(iter))
141 iter = NULL;
142 out:
143 mutex_unlock(&kvm->arch.config_lock);
144 return iter;
145 }
146
147 static void *vgic_debug_next(struct seq_file *s, void *v, loff_t *pos)
148 {
149 struct kvm *kvm = s->private;
150 struct vgic_state_iter *iter = kvm->arch.vgic.iter;
151
152 ++*pos;
153 iter_next(kvm, iter);
154 if (end_of_vgic(iter))
155 iter = NULL;
156 return iter;
157 }
158
159 static void vgic_debug_stop(struct seq_file *s, void *v)
160 {
161 struct kvm *kvm = s->private;
162 struct vgic_state_iter *iter;
163
164 /*
165 * If the seq file wasn't properly opened, there's nothing to clearn
166 * up.
167 */
168 if (IS_ERR(v))
169 return;
170
171 mutex_lock(&kvm->arch.config_lock);
172 iter = kvm->arch.vgic.iter;
173 iter_unmark_lpis(kvm);
174 kfree(iter);
175 kvm->arch.vgic.iter = NULL;
176 mutex_unlock(&kvm->arch.config_lock);
177 }
178
179 static void print_dist_state(struct seq_file *s, struct vgic_dist *dist,
180 struct vgic_state_iter *iter)
181 {
182 bool v3 = dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3;
183
184 seq_printf(s, "Distributor\n");
185 seq_printf(s, "===========\n");
186 seq_printf(s, "vgic_model:\t%s\n", v3 ? "GICv3" : "GICv2");
187 seq_printf(s, "nr_spis:\t%d\n", dist->nr_spis);
188 if (v3)
189 seq_printf(s, "nr_lpis:\t%d\n", iter->nr_lpis);
190 seq_printf(s, "enabled:\t%d\n", dist->enabled);
191 seq_printf(s, "\n");
192
193 seq_printf(s, "P=pending_latch, L=line_level, A=active\n");
194 seq_printf(s, "E=enabled, H=hw, C=config (level=1, edge=0)\n");
195 seq_printf(s, "G=group\n");
196 }
197
198 static void print_header(struct seq_file *s, struct vgic_irq *irq,
199 struct kvm_vcpu *vcpu)
200 {
201 int id = 0;
202 char *hdr = "SPI ";
203
204 if (vcpu) {
205 hdr = "VCPU";
206 id = vcpu->vcpu_idx;
207 }
208
209 seq_printf(s, "\n");
210 seq_printf(s, "%s%2d TYP ID TGT_ID PLAEHCG HWID TARGET SRC PRI VCPU_ID\n", hdr, id);
211 seq_printf(s, "----------------------------------------------------------------\n");
212 }
213
214 static void print_irq_state(struct seq_file *s, struct vgic_irq *irq,
215 struct kvm_vcpu *vcpu)
216 {
217 char *type;
218 bool pending;
219
220 if (irq->intid < VGIC_NR_SGIS)
221 type = "SGI";
222 else if (irq->intid < VGIC_NR_PRIVATE_IRQS)
223 type = "PPI";
224 else if (irq->intid < VGIC_MAX_SPI)
225 type = "SPI";
226 else
227 type = "LPI";
228
229 if (irq->intid ==0 || irq->intid == VGIC_NR_PRIVATE_IRQS)
230 print_header(s, irq, vcpu);
231
232 pending = irq->pending_latch;
233 if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
234 int err;
235
236 err = irq_get_irqchip_state(irq->host_irq,
237 IRQCHIP_STATE_PENDING,
238 &pending);
239 WARN_ON_ONCE(err);
240 }
241
242 seq_printf(s, " %s %4d "
243 " %2d "
244 "%d%d%d%d%d%d%d "
245 "%8d "
246 "%8x "
247 " %2x "
248 "%3d "
249 " %2d "
250 "\n",
251 type, irq->intid,
252 (irq->target_vcpu) ? irq->target_vcpu->vcpu_idx : -1,
253 pending,
254 irq->line_level,
255 irq->active,
256 irq->enabled,
257 irq->hw,
258 irq->config == VGIC_CONFIG_LEVEL,
259 irq->group,
260 irq->hwintid,
261 irq->mpidr,
262 irq->source,
263 irq->priority,
264 (irq->vcpu) ? irq->vcpu->vcpu_idx : -1);
265 }
266
267 static int vgic_debug_show(struct seq_file *s, void *v)
268 {
269 struct kvm *kvm = s->private;
270 struct vgic_state_iter *iter = v;
271 struct vgic_irq *irq;
272 struct kvm_vcpu *vcpu = NULL;
273 unsigned long flags;
274
275 if (iter->dist_id == 0) {
276 print_dist_state(s, &kvm->arch.vgic, iter);
277 return 0;
278 }
279
280 if (!kvm->arch.vgic.initialized)
281 return 0;
282
283 if (iter->vcpu_id < iter->nr_cpus)
284 vcpu = kvm_get_vcpu(kvm, iter->vcpu_id);
285
286 /*
287 * Expect this to succeed, as iter_mark_lpis() takes a reference on
288 * every LPI to be visited.
289 */
290 irq = vgic_get_irq(kvm, vcpu, iter->intid);
291 if (WARN_ON_ONCE(!irq))
292 return -EINVAL;
293
294 raw_spin_lock_irqsave(&irq->irq_lock, flags);
295 print_irq_state(s, irq, vcpu);
296 raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
297
298 vgic_put_irq(kvm, irq);
299 return 0;
300 }
301
302 static const struct seq_operations vgic_debug_sops = {
303 .start = vgic_debug_start,
304 .next = vgic_debug_next,
305 .stop = vgic_debug_stop,
306 .show = vgic_debug_show
307 };
308
309 DEFINE_SEQ_ATTRIBUTE(vgic_debug);
310
311 void vgic_debug_init(struct kvm *kvm)
312 {
313 debugfs_create_file("vgic-state", 0444, kvm->debugfs_dentry, kvm,
314 &vgic_debug_fops);
315 }
316
317 void vgic_debug_destroy(struct kvm *kvm)
318 {
319 }
320
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