qemu/plugins/api.c
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   1/*
   2 * QEMU Plugin API
   3 *
   4 * This provides the API that is available to the plugins to interact
   5 * with QEMU. We have to be careful not to expose internal details of
   6 * how QEMU works so we abstract out things like translation and
   7 * instructions to anonymous data types:
   8 *
   9 *  qemu_plugin_tb
  10 *  qemu_plugin_insn
  11 *
  12 * Which can then be passed back into the API to do additional things.
  13 * As such all the public functions in here are exported in
  14 * qemu-plugin.h.
  15 *
  16 * The general life-cycle of a plugin is:
  17 *
  18 *  - plugin is loaded, public qemu_plugin_install called
  19 *    - the install func registers callbacks for events
  20 *    - usually an atexit_cb is registered to dump info at the end
  21 *  - when a registered event occurs the plugin is called
  22 *     - some events pass additional info
  23 *     - during translation the plugin can decide to instrument any
  24 *       instruction
  25 *  - when QEMU exits all the registered atexit callbacks are called
  26 *
  27 * Copyright (C) 2017, Emilio G. Cota <cota@braap.org>
  28 * Copyright (C) 2019, Linaro
  29 *
  30 * License: GNU GPL, version 2 or later.
  31 *   See the COPYING file in the top-level directory.
  32 *
  33 * SPDX-License-Identifier: GPL-2.0-or-later
  34 *
  35 */
  36
  37#include "qemu/osdep.h"
  38#include "qemu/plugin.h"
  39#include "tcg/tcg.h"
  40#include "exec/exec-all.h"
  41#include "exec/ram_addr.h"
  42#include "disas/disas.h"
  43#include "plugin.h"
  44#ifndef CONFIG_USER_ONLY
  45#include "qemu/plugin-memory.h"
  46#include "hw/boards.h"
  47#endif
  48
  49/* Uninstall and Reset handlers */
  50
  51void qemu_plugin_uninstall(qemu_plugin_id_t id, qemu_plugin_simple_cb_t cb)
  52{
  53    plugin_reset_uninstall(id, cb, false);
  54}
  55
  56void qemu_plugin_reset(qemu_plugin_id_t id, qemu_plugin_simple_cb_t cb)
  57{
  58    plugin_reset_uninstall(id, cb, true);
  59}
  60
  61/*
  62 * Plugin Register Functions
  63 *
  64 * This allows the plugin to register callbacks for various events
  65 * during the translation.
  66 */
  67
  68void qemu_plugin_register_vcpu_init_cb(qemu_plugin_id_t id,
  69                                       qemu_plugin_vcpu_simple_cb_t cb)
  70{
  71    plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_INIT, cb);
  72}
  73
  74void qemu_plugin_register_vcpu_exit_cb(qemu_plugin_id_t id,
  75                                       qemu_plugin_vcpu_simple_cb_t cb)
  76{
  77    plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_EXIT, cb);
  78}
  79
  80void qemu_plugin_register_vcpu_tb_exec_cb(struct qemu_plugin_tb *tb,
  81                                          qemu_plugin_vcpu_udata_cb_t cb,
  82                                          enum qemu_plugin_cb_flags flags,
  83                                          void *udata)
  84{
  85    if (!tb->mem_only) {
  86        plugin_register_dyn_cb__udata(&tb->cbs[PLUGIN_CB_REGULAR],
  87                                      cb, flags, udata);
  88    }
  89}
  90
  91void qemu_plugin_register_vcpu_tb_exec_inline(struct qemu_plugin_tb *tb,
  92                                              enum qemu_plugin_op op,
  93                                              void *ptr, uint64_t imm)
  94{
  95    if (!tb->mem_only) {
  96        plugin_register_inline_op(&tb->cbs[PLUGIN_CB_INLINE], 0, op, ptr, imm);
  97    }
  98}
  99
 100void qemu_plugin_register_vcpu_insn_exec_cb(struct qemu_plugin_insn *insn,
 101                                            qemu_plugin_vcpu_udata_cb_t cb,
 102                                            enum qemu_plugin_cb_flags flags,
 103                                            void *udata)
 104{
 105    if (!insn->mem_only) {
 106        plugin_register_dyn_cb__udata(&insn->cbs[PLUGIN_CB_INSN][PLUGIN_CB_REGULAR],
 107                                      cb, flags, udata);
 108    }
 109}
 110
 111void qemu_plugin_register_vcpu_insn_exec_inline(struct qemu_plugin_insn *insn,
 112                                                enum qemu_plugin_op op,
 113                                                void *ptr, uint64_t imm)
 114{
 115    if (!insn->mem_only) {
 116        plugin_register_inline_op(&insn->cbs[PLUGIN_CB_INSN][PLUGIN_CB_INLINE],
 117                                  0, op, ptr, imm);
 118    }
 119}
 120
 121
 122/*
 123 * We always plant memory instrumentation because they don't finalise until
 124 * after the operation has complete.
 125 */
 126void qemu_plugin_register_vcpu_mem_cb(struct qemu_plugin_insn *insn,
 127                                      qemu_plugin_vcpu_mem_cb_t cb,
 128                                      enum qemu_plugin_cb_flags flags,
 129                                      enum qemu_plugin_mem_rw rw,
 130                                      void *udata)
 131{
 132    plugin_register_vcpu_mem_cb(&insn->cbs[PLUGIN_CB_MEM][PLUGIN_CB_REGULAR],
 133                                    cb, flags, rw, udata);
 134}
 135
 136void qemu_plugin_register_vcpu_mem_inline(struct qemu_plugin_insn *insn,
 137                                          enum qemu_plugin_mem_rw rw,
 138                                          enum qemu_plugin_op op, void *ptr,
 139                                          uint64_t imm)
 140{
 141    plugin_register_inline_op(&insn->cbs[PLUGIN_CB_MEM][PLUGIN_CB_INLINE],
 142                              rw, op, ptr, imm);
 143}
 144
 145void qemu_plugin_register_vcpu_tb_trans_cb(qemu_plugin_id_t id,
 146                                           qemu_plugin_vcpu_tb_trans_cb_t cb)
 147{
 148    plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_TB_TRANS, cb);
 149}
 150
 151void qemu_plugin_register_vcpu_syscall_cb(qemu_plugin_id_t id,
 152                                          qemu_plugin_vcpu_syscall_cb_t cb)
 153{
 154    plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_SYSCALL, cb);
 155}
 156
 157void
 158qemu_plugin_register_vcpu_syscall_ret_cb(qemu_plugin_id_t id,
 159                                         qemu_plugin_vcpu_syscall_ret_cb_t cb)
 160{
 161    plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_SYSCALL_RET, cb);
 162}
 163
 164/*
 165 * Plugin Queries
 166 *
 167 * These are queries that the plugin can make to gauge information
 168 * from our opaque data types. We do not want to leak internal details
 169 * here just information useful to the plugin.
 170 */
 171
 172/*
 173 * Translation block information:
 174 *
 175 * A plugin can query the virtual address of the start of the block
 176 * and the number of instructions in it. It can also get access to
 177 * each translated instruction.
 178 */
 179
 180size_t qemu_plugin_tb_n_insns(const struct qemu_plugin_tb *tb)
 181{
 182    return tb->n;
 183}
 184
 185uint64_t qemu_plugin_tb_vaddr(const struct qemu_plugin_tb *tb)
 186{
 187    return tb->vaddr;
 188}
 189
 190struct qemu_plugin_insn *
 191qemu_plugin_tb_get_insn(const struct qemu_plugin_tb *tb, size_t idx)
 192{
 193    struct qemu_plugin_insn *insn;
 194    if (unlikely(idx >= tb->n)) {
 195        return NULL;
 196    }
 197    insn = g_ptr_array_index(tb->insns, idx);
 198    insn->mem_only = tb->mem_only;
 199    return insn;
 200}
 201
 202/*
 203 * Instruction information
 204 *
 205 * These queries allow the plugin to retrieve information about each
 206 * instruction being translated.
 207 */
 208
 209const void *qemu_plugin_insn_data(const struct qemu_plugin_insn *insn)
 210{
 211    return insn->data->data;
 212}
 213
 214size_t qemu_plugin_insn_size(const struct qemu_plugin_insn *insn)
 215{
 216    return insn->data->len;
 217}
 218
 219uint64_t qemu_plugin_insn_vaddr(const struct qemu_plugin_insn *insn)
 220{
 221    return insn->vaddr;
 222}
 223
 224void *qemu_plugin_insn_haddr(const struct qemu_plugin_insn *insn)
 225{
 226    return insn->haddr;
 227}
 228
 229char *qemu_plugin_insn_disas(const struct qemu_plugin_insn *insn)
 230{
 231    CPUState *cpu = current_cpu;
 232    return plugin_disas(cpu, insn->vaddr, insn->data->len);
 233}
 234
 235const char *qemu_plugin_insn_symbol(const struct qemu_plugin_insn *insn)
 236{
 237    const char *sym = lookup_symbol(insn->vaddr);
 238    return sym[0] != 0 ? sym : NULL;
 239}
 240
 241/*
 242 * The memory queries allow the plugin to query information about a
 243 * memory access.
 244 */
 245
 246unsigned qemu_plugin_mem_size_shift(qemu_plugin_meminfo_t info)
 247{
 248    MemOp op = get_memop(info);
 249    return op & MO_SIZE;
 250}
 251
 252bool qemu_plugin_mem_is_sign_extended(qemu_plugin_meminfo_t info)
 253{
 254    MemOp op = get_memop(info);
 255    return op & MO_SIGN;
 256}
 257
 258bool qemu_plugin_mem_is_big_endian(qemu_plugin_meminfo_t info)
 259{
 260    MemOp op = get_memop(info);
 261    return (op & MO_BSWAP) == MO_BE;
 262}
 263
 264bool qemu_plugin_mem_is_store(qemu_plugin_meminfo_t info)
 265{
 266    return get_plugin_meminfo_rw(info) & QEMU_PLUGIN_MEM_W;
 267}
 268
 269/*
 270 * Virtual Memory queries
 271 */
 272
 273#ifdef CONFIG_SOFTMMU
 274static __thread struct qemu_plugin_hwaddr hwaddr_info;
 275#endif
 276
 277struct qemu_plugin_hwaddr *qemu_plugin_get_hwaddr(qemu_plugin_meminfo_t info,
 278                                                  uint64_t vaddr)
 279{
 280#ifdef CONFIG_SOFTMMU
 281    CPUState *cpu = current_cpu;
 282    unsigned int mmu_idx = get_mmuidx(info);
 283    enum qemu_plugin_mem_rw rw = get_plugin_meminfo_rw(info);
 284    hwaddr_info.is_store = (rw & QEMU_PLUGIN_MEM_W) != 0;
 285
 286    if (!tlb_plugin_lookup(cpu, vaddr, mmu_idx,
 287                           hwaddr_info.is_store, &hwaddr_info)) {
 288        error_report("invalid use of qemu_plugin_get_hwaddr");
 289        return NULL;
 290    }
 291
 292    return &hwaddr_info;
 293#else
 294    return NULL;
 295#endif
 296}
 297
 298bool qemu_plugin_hwaddr_is_io(const struct qemu_plugin_hwaddr *haddr)
 299{
 300#ifdef CONFIG_SOFTMMU
 301    return haddr->is_io;
 302#else
 303    return false;
 304#endif
 305}
 306
 307uint64_t qemu_plugin_hwaddr_phys_addr(const struct qemu_plugin_hwaddr *haddr)
 308{
 309#ifdef CONFIG_SOFTMMU
 310    if (haddr) {
 311        if (!haddr->is_io) {
 312            RAMBlock *block;
 313            ram_addr_t offset;
 314            void *hostaddr = haddr->v.ram.hostaddr;
 315
 316            block = qemu_ram_block_from_host(hostaddr, false, &offset);
 317            if (!block) {
 318                error_report("Bad host ram pointer %p", haddr->v.ram.hostaddr);
 319                abort();
 320            }
 321
 322            return block->offset + offset + block->mr->addr;
 323        } else {
 324            MemoryRegionSection *mrs = haddr->v.io.section;
 325            return mrs->offset_within_address_space + haddr->v.io.offset;
 326        }
 327    }
 328#endif
 329    return 0;
 330}
 331
 332const char *qemu_plugin_hwaddr_device_name(const struct qemu_plugin_hwaddr *h)
 333{
 334#ifdef CONFIG_SOFTMMU
 335    if (h && h->is_io) {
 336        MemoryRegionSection *mrs = h->v.io.section;
 337        if (!mrs->mr->name) {
 338            unsigned long maddr = 0xffffffff & (uintptr_t) mrs->mr;
 339            g_autofree char *temp = g_strdup_printf("anon%08lx", maddr);
 340            return g_intern_string(temp);
 341        } else {
 342            return g_intern_string(mrs->mr->name);
 343        }
 344    } else {
 345        return g_intern_static_string("RAM");
 346    }
 347#else
 348    return g_intern_static_string("Invalid");
 349#endif
 350}
 351
 352/*
 353 * Queries to the number and potential maximum number of vCPUs there
 354 * will be. This helps the plugin dimension per-vcpu arrays.
 355 */
 356
 357#ifndef CONFIG_USER_ONLY
 358static MachineState * get_ms(void)
 359{
 360    return MACHINE(qdev_get_machine());
 361}
 362#endif
 363
 364int qemu_plugin_n_vcpus(void)
 365{
 366#ifdef CONFIG_USER_ONLY
 367    return -1;
 368#else
 369    return get_ms()->smp.cpus;
 370#endif
 371}
 372
 373int qemu_plugin_n_max_vcpus(void)
 374{
 375#ifdef CONFIG_USER_ONLY
 376    return -1;
 377#else
 378    return get_ms()->smp.max_cpus;
 379#endif
 380}
 381
 382/*
 383 * Plugin output
 384 */
 385void qemu_plugin_outs(const char *string)
 386{
 387    qemu_log_mask(CPU_LOG_PLUGIN, "%s", string);
 388}
 389
 390bool qemu_plugin_bool_parse(const char *name, const char *value, bool *ret)
 391{
 392    return name && value && qapi_bool_parse(name, value, ret, NULL);
 393}
 394