virt/kvm/arm/vgic/vgic-debug.c

   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         int intid;
  32         int lpi_idx;
  33         u32 *lpi_array;
  34 };
  35
  36 static void iter_next(struct vgic_state_iter *iter)
  37 {
  38         if (iter->dist_id == 0) {
  39                 iter->dist_id++;
  40                 return;
  41         }
  42
  43         iter->intid++;
  44         if (iter->intid == VGIC_NR_PRIVATE_IRQS &&
  45             ++iter->vcpu_id < iter->nr_cpus)
  46                 iter->intid = 0;
  47
  48         if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS)) {
  49                 if (iter->lpi_idx < iter->nr_lpis)
  50                         iter->intid = iter->lpi_array[iter->lpi_idx];
  51                 iter->lpi_idx++;
  52         }
  53 }
  54
  55 static void iter_init(struct kvm *kvm, struct vgic_state_iter *iter,
  56                       loff_t pos)
  57 {
  58         int nr_cpus = atomic_read(&kvm->online_vcpus);
  59
  60         memset(iter, 0, sizeof(*iter));
  61
  62         iter->nr_cpus = nr_cpus;
  63         iter->nr_spis = kvm->arch.vgic.nr_spis;
  64         if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
  65                 iter->nr_lpis = vgic_copy_lpi_list(kvm, NULL, &iter->lpi_array);
  66                 if (iter->nr_lpis < 0)
  67                         iter->nr_lpis = 0;
  68         }
  69
  70         /* Fast forward to the right position if needed */
  71         while (pos--)
  72                 iter_next(iter);
  73 }
  74
  75 static bool end_of_vgic(struct vgic_state_iter *iter)
  76 {
  77         return iter->dist_id > 0 &&
  78                 iter->vcpu_id == iter->nr_cpus &&
  79                 iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS) &&
  80                 iter->lpi_idx > iter->nr_lpis;
  81 }
  82
  83 static void *vgic_debug_start(struct seq_file *s, loff_t *pos)
  84 {
  85         struct kvm *kvm = (struct kvm *)s->private;
  86         struct vgic_state_iter *iter;
  87
  88         mutex_lock(&kvm->lock);
  89         iter = kvm->arch.vgic.iter;
  90         if (iter) {
  91                 iter = ERR_PTR(-EBUSY);
  92                 goto out;
  93         }
  94
  95         iter = kmalloc(sizeof(*iter), GFP_KERNEL);
  96         if (!iter) {
  97                 iter = ERR_PTR(-ENOMEM);
  98                 goto out;
  99         }
 100
 101         iter_init(kvm, iter, *pos);
 102         kvm->arch.vgic.iter = iter;
 103
 104         if (end_of_vgic(iter))
 105                 iter = NULL;
 106 out:
 107         mutex_unlock(&kvm->lock);
 108         return iter;
 109 }
 110
 111 static void *vgic_debug_next(struct seq_file *s, void *v, loff_t *pos)
 112 {
 113         struct kvm *kvm = (struct kvm *)s->private;
 114         struct vgic_state_iter *iter = kvm->arch.vgic.iter;
 115
 116         ++*pos;
 117         iter_next(iter);
 118         if (end_of_vgic(iter))
 119                 iter = NULL;
 120         return iter;
 121 }
 122
 123 static void vgic_debug_stop(struct seq_file *s, void *v)
 124 {
 125         struct kvm *kvm = (struct kvm *)s->private;
 126         struct vgic_state_iter *iter;
 127
 128         /*
 129          * If the seq file wasn't properly opened, there's nothing to clearn
 130          * up.
 131          */
 132         if (IS_ERR(v))
 133                 return;
 134
 135         mutex_lock(&kvm->lock);
 136         iter = kvm->arch.vgic.iter;
 137         kfree(iter->lpi_array);
 138         kfree(iter);
 139         kvm->arch.vgic.iter = NULL;
 140         mutex_unlock(&kvm->lock);
 141 }
 142
 143 static void print_dist_state(struct seq_file *s, struct vgic_dist *dist)
 144 {
 145         bool v3 = dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3;
 146
 147         seq_printf(s, "Distributor\n");
 148         seq_printf(s, "===========\n");
 149         seq_printf(s, "vgic_model:\t%s\n", v3 ? "GICv3" : "GICv2");
 150         seq_printf(s, "nr_spis:\t%d\n", dist->nr_spis);
 151         if (v3)
 152                 seq_printf(s, "nr_lpis:\t%d\n", dist->lpi_list_count);
 153         seq_printf(s, "enabled:\t%d\n", dist->enabled);
 154         seq_printf(s, "\n");
 155
 156         seq_printf(s, "P=pending_latch, L=line_level, A=active\n");
 157         seq_printf(s, "E=enabled, H=hw, C=config (level=1, edge=0)\n");
 158         seq_printf(s, "G=group\n");
 159 }
 160
 161 static void print_header(struct seq_file *s, struct vgic_irq *irq,
 162                          struct kvm_vcpu *vcpu)
 163 {
 164         int id = 0;
 165         char *hdr = "SPI ";
 166
 167         if (vcpu) {
 168                 hdr = "VCPU";
 169                 id = vcpu->vcpu_id;
 170         }
 171
 172         seq_printf(s, "\n");
 173         seq_printf(s, "%s%2d TYP   ID TGT_ID PLAEHCG     HWID   TARGET SRC PRI VCPU_ID\n", hdr, id);
 174         seq_printf(s, "----------------------------------------------------------------\n");
 175 }
 176
 177 static void print_irq_state(struct seq_file *s, struct vgic_irq *irq,
 178                             struct kvm_vcpu *vcpu)
 179 {
 180         char *type;
 181         if (irq->intid < VGIC_NR_SGIS)
 182                 type = "SGI";
 183         else if (irq->intid < VGIC_NR_PRIVATE_IRQS)
 184                 type = "PPI";
 185         else if (irq->intid < VGIC_MAX_SPI)
 186                 type = "SPI";
 187         else
 188                 type = "LPI";
 189
 190         if (irq->intid ==0 || irq->intid == VGIC_NR_PRIVATE_IRQS)
 191                 print_header(s, irq, vcpu);
 192
 193         seq_printf(s, "       %s %4d "
 194                       "    %2d "
 195                       "%d%d%d%d%d%d%d "
 196                       "%8d "
 197                       "%8x "
 198                       " %2x "
 199                       "%3d "
 200                       "     %2d "
 201                       "\n",
 202                         type, irq->intid,
 203                         (irq->target_vcpu) ? irq->target_vcpu->vcpu_id : -1,
 204                         irq->pending_latch,
 205                         irq->line_level,
 206                         irq->active,
 207                         irq->enabled,
 208                         irq->hw,
 209                         irq->config == VGIC_CONFIG_LEVEL,
 210                         irq->group,
 211                         irq->hwintid,
 212                         irq->mpidr,
 213                         irq->source,
 214                         irq->priority,
 215                         (irq->vcpu) ? irq->vcpu->vcpu_id : -1);
 216 }
 217
 218 static int vgic_debug_show(struct seq_file *s, void *v)
 219 {
 220         struct kvm *kvm = (struct kvm *)s->private;
 221         struct vgic_state_iter *iter = (struct vgic_state_iter *)v;
 222         struct vgic_irq *irq;
 223         struct kvm_vcpu *vcpu = NULL;
 224         unsigned long flags;
 225
 226         if (iter->dist_id == 0) {
 227                 print_dist_state(s, &kvm->arch.vgic);
 228                 return 0;
 229         }
 230
 231         if (!kvm->arch.vgic.initialized)
 232                 return 0;
 233
 234         if (iter->vcpu_id < iter->nr_cpus)
 235                 vcpu = kvm_get_vcpu(kvm, iter->vcpu_id);
 236
 237         irq = vgic_get_irq(kvm, vcpu, iter->intid);
 238         if (!irq) {
 239                 seq_printf(s, "       LPI %4d freed\n", iter->intid);
 240                 return 0;
 241         }
 242
 243         raw_spin_lock_irqsave(&irq->irq_lock, flags);
 244         print_irq_state(s, irq, vcpu);
 245         raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 246
 247         vgic_put_irq(kvm, irq);
 248         return 0;
 249 }
 250
 251 static const struct seq_operations vgic_debug_seq_ops = {
 252         .start = vgic_debug_start,
 253         .next  = vgic_debug_next,
 254         .stop  = vgic_debug_stop,
 255         .show  = vgic_debug_show
 256 };
 257
 258 static int debug_open(struct inode *inode, struct file *file)
 259 {
 260         int ret;
 261         ret = seq_open(file, &vgic_debug_seq_ops);
 262         if (!ret) {
 263                 struct seq_file *seq;
 264                 /* seq_open will have modified file->private_data */
 265                 seq = file->private_data;
 266                 seq->private = inode->i_private;
 267         }
 268
 269         return ret;
 270 };
 271
 272 static const struct file_operations vgic_debug_fops = {
 273         .owner   = THIS_MODULE,
 274         .open    = debug_open,
 275         .read    = seq_read,
 276         .llseek  = seq_lseek,
 277         .release = seq_release
 278 };
 279
 280 void vgic_debug_init(struct kvm *kvm)
 281 {
 282         debugfs_create_file("vgic-state", 0444, kvm->debugfs_dentry, kvm,
 283                             &vgic_debug_fops);
 284 }
 285
 286 void vgic_debug_destroy(struct kvm *kvm)
 287 {
 288 }