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

   1 /*
   2  * Copyright (C) 2016 Linaro
   3  * Author: Christoffer Dall <christoffer.dall@linaro.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <linux/cpu.h>
  19 #include <linux/debugfs.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/kvm_host.h>
  22 #include <linux/seq_file.h>
  23 #include <kvm/arm_vgic.h>
  24 #include <asm/kvm_mmu.h>
  25 #include "vgic.h"
  26
  27 /*
  28  * Structure to control looping through the entire vgic state.  We start at
  29  * zero for each field and move upwards.  So, if dist_id is 0 we print the
  30  * distributor info.  When dist_id is 1, we have already printed it and move
  31  * on.
  32  *
  33  * When vcpu_id < nr_cpus we print the vcpu info until vcpu_id == nr_cpus and
  34  * so on.
  35  */
  36 struct vgic_state_iter {
  37         int nr_cpus;
  38         int nr_spis;
  39         int nr_lpis;
  40         int dist_id;
  41         int vcpu_id;
  42         int intid;
  43         int lpi_idx;
  44         u32 *lpi_array;
  45 };
  46
  47 static void iter_next(struct vgic_state_iter *iter)
  48 {
  49         if (iter->dist_id == 0) {
  50                 iter->dist_id++;
  51                 return;
  52         }
  53
  54         iter->intid++;
  55         if (iter->intid == VGIC_NR_PRIVATE_IRQS &&
  56             ++iter->vcpu_id < iter->nr_cpus)
  57                 iter->intid = 0;
  58
  59         if (iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS)) {
  60                 if (iter->lpi_idx < iter->nr_lpis)
  61                         iter->intid = iter->lpi_array[iter->lpi_idx];
  62                 iter->lpi_idx++;
  63         }
  64 }
  65
  66 static void iter_init(struct kvm *kvm, struct vgic_state_iter *iter,
  67                       loff_t pos)
  68 {
  69         int nr_cpus = atomic_read(&kvm->online_vcpus);
  70
  71         memset(iter, 0, sizeof(*iter));
  72
  73         iter->nr_cpus = nr_cpus;
  74         iter->nr_spis = kvm->arch.vgic.nr_spis;
  75         if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
  76                 iter->nr_lpis = vgic_copy_lpi_list(kvm, NULL, &iter->lpi_array);
  77                 if (iter->nr_lpis < 0)
  78                         iter->nr_lpis = 0;
  79         }
  80
  81         /* Fast forward to the right position if needed */
  82         while (pos--)
  83                 iter_next(iter);
  84 }
  85
  86 static bool end_of_vgic(struct vgic_state_iter *iter)
  87 {
  88         return iter->dist_id > 0 &&
  89                 iter->vcpu_id == iter->nr_cpus &&
  90                 iter->intid >= (iter->nr_spis + VGIC_NR_PRIVATE_IRQS) &&
  91                 iter->lpi_idx > iter->nr_lpis;
  92 }
  93
  94 static void *vgic_debug_start(struct seq_file *s, loff_t *pos)
  95 {
  96         struct kvm *kvm = (struct kvm *)s->private;
  97         struct vgic_state_iter *iter;
  98
  99         mutex_lock(&kvm->lock);
 100         iter = kvm->arch.vgic.iter;
 101         if (iter) {
 102                 iter = ERR_PTR(-EBUSY);
 103                 goto out;
 104         }
 105
 106         iter = kmalloc(sizeof(*iter), GFP_KERNEL);
 107         if (!iter) {
 108                 iter = ERR_PTR(-ENOMEM);
 109                 goto out;
 110         }
 111
 112         iter_init(kvm, iter, *pos);
 113         kvm->arch.vgic.iter = iter;
 114
 115         if (end_of_vgic(iter))
 116                 iter = NULL;
 117 out:
 118         mutex_unlock(&kvm->lock);
 119         return iter;
 120 }
 121
 122 static void *vgic_debug_next(struct seq_file *s, void *v, loff_t *pos)
 123 {
 124         struct kvm *kvm = (struct kvm *)s->private;
 125         struct vgic_state_iter *iter = kvm->arch.vgic.iter;
 126
 127         ++*pos;
 128         iter_next(iter);
 129         if (end_of_vgic(iter))
 130                 iter = NULL;
 131         return iter;
 132 }
 133
 134 static void vgic_debug_stop(struct seq_file *s, void *v)
 135 {
 136         struct kvm *kvm = (struct kvm *)s->private;
 137         struct vgic_state_iter *iter;
 138
 139         /*
 140          * If the seq file wasn't properly opened, there's nothing to clearn
 141          * up.
 142          */
 143         if (IS_ERR(v))
 144                 return;
 145
 146         mutex_lock(&kvm->lock);
 147         iter = kvm->arch.vgic.iter;
 148         kfree(iter->lpi_array);
 149         kfree(iter);
 150         kvm->arch.vgic.iter = NULL;
 151         mutex_unlock(&kvm->lock);
 152 }
 153
 154 static void print_dist_state(struct seq_file *s, struct vgic_dist *dist)
 155 {
 156         bool v3 = dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3;
 157
 158         seq_printf(s, "Distributor\n");
 159         seq_printf(s, "===========\n");
 160         seq_printf(s, "vgic_model:\t%s\n", v3 ? "GICv3" : "GICv2");
 161         seq_printf(s, "nr_spis:\t%d\n", dist->nr_spis);
 162         if (v3)
 163                 seq_printf(s, "nr_lpis:\t%d\n", dist->lpi_list_count);
 164         seq_printf(s, "enabled:\t%d\n", dist->enabled);
 165         seq_printf(s, "\n");
 166
 167         seq_printf(s, "P=pending_latch, L=line_level, A=active\n");
 168         seq_printf(s, "E=enabled, H=hw, C=config (level=1, edge=0)\n");
 169         seq_printf(s, "G=group\n");
 170 }
 171
 172 static void print_header(struct seq_file *s, struct vgic_irq *irq,
 173                          struct kvm_vcpu *vcpu)
 174 {
 175         int id = 0;
 176         char *hdr = "SPI ";
 177
 178         if (vcpu) {
 179                 hdr = "VCPU";
 180                 id = vcpu->vcpu_id;
 181         }
 182
 183         seq_printf(s, "\n");
 184         seq_printf(s, "%s%2d TYP   ID TGT_ID PLAEHCG     HWID   TARGET SRC PRI VCPU_ID\n", hdr, id);
 185         seq_printf(s, "----------------------------------------------------------------\n");
 186 }
 187
 188 static void print_irq_state(struct seq_file *s, struct vgic_irq *irq,
 189                             struct kvm_vcpu *vcpu)
 190 {
 191         char *type;
 192         if (irq->intid < VGIC_NR_SGIS)
 193                 type = "SGI";
 194         else if (irq->intid < VGIC_NR_PRIVATE_IRQS)
 195                 type = "PPI";
 196         else if (irq->intid < VGIC_MAX_SPI)
 197                 type = "SPI";
 198         else
 199                 type = "LPI";
 200
 201         if (irq->intid ==0 || irq->intid == VGIC_NR_PRIVATE_IRQS)
 202                 print_header(s, irq, vcpu);
 203
 204         seq_printf(s, "       %s %4d "
 205                       "    %2d "
 206                       "%d%d%d%d%d%d%d "
 207                       "%8d "
 208                       "%8x "
 209                       " %2x "
 210                       "%3d "
 211                       "     %2d "
 212                       "\n",
 213                         type, irq->intid,
 214                         (irq->target_vcpu) ? irq->target_vcpu->vcpu_id : -1,
 215                         irq->pending_latch,
 216                         irq->line_level,
 217                         irq->active,
 218                         irq->enabled,
 219                         irq->hw,
 220                         irq->config == VGIC_CONFIG_LEVEL,
 221                         irq->group,
 222                         irq->hwintid,
 223                         irq->mpidr,
 224                         irq->source,
 225                         irq->priority,
 226                         (irq->vcpu) ? irq->vcpu->vcpu_id : -1);
 227 }
 228
 229 static int vgic_debug_show(struct seq_file *s, void *v)
 230 {
 231         struct kvm *kvm = (struct kvm *)s->private;
 232         struct vgic_state_iter *iter = (struct vgic_state_iter *)v;
 233         struct vgic_irq *irq;
 234         struct kvm_vcpu *vcpu = NULL;
 235         unsigned long flags;
 236
 237         if (iter->dist_id == 0) {
 238                 print_dist_state(s, &kvm->arch.vgic);
 239                 return 0;
 240         }
 241
 242         if (!kvm->arch.vgic.initialized)
 243                 return 0;
 244
 245         if (iter->vcpu_id < iter->nr_cpus)
 246                 vcpu = kvm_get_vcpu(kvm, iter->vcpu_id);
 247
 248         irq = vgic_get_irq(kvm, vcpu, iter->intid);
 249         if (!irq) {
 250                 seq_printf(s, "       LPI %4d freed\n", iter->intid);
 251                 return 0;
 252         }
 253
 254         spin_lock_irqsave(&irq->irq_lock, flags);
 255         print_irq_state(s, irq, vcpu);
 256         spin_unlock_irqrestore(&irq->irq_lock, flags);
 257
 258         vgic_put_irq(kvm, irq);
 259         return 0;
 260 }
 261
 262 static const struct seq_operations vgic_debug_seq_ops = {
 263         .start = vgic_debug_start,
 264         .next  = vgic_debug_next,
 265         .stop  = vgic_debug_stop,
 266         .show  = vgic_debug_show
 267 };
 268
 269 static int debug_open(struct inode *inode, struct file *file)
 270 {
 271         int ret;
 272         ret = seq_open(file, &vgic_debug_seq_ops);
 273         if (!ret) {
 274                 struct seq_file *seq;
 275                 /* seq_open will have modified file->private_data */
 276                 seq = file->private_data;
 277                 seq->private = inode->i_private;
 278         }
 279
 280         return ret;
 281 };
 282
 283 static const struct file_operations vgic_debug_fops = {
 284         .owner   = THIS_MODULE,
 285         .open    = debug_open,
 286         .read    = seq_read,
 287         .llseek  = seq_lseek,
 288         .release = seq_release
 289 };
 290
 291 void vgic_debug_init(struct kvm *kvm)
 292 {
 293         debugfs_create_file("vgic-state", 0444, kvm->debugfs_dentry, kvm,
 294                             &vgic_debug_fops);
 295 }
 296
 297 void vgic_debug_destroy(struct kvm *kvm)
 298 {
 299 }