plugins/api.c - qemu - Git at Google

 /*
  * QEMU Plugin API
  *
  * This provides the API that is available to the plugins to interact
  * with QEMU. We have to be careful not to expose internal details of
  * how QEMU works so we abstract out things like translation and
  * instructions to anonymous data types:
  *
  *  qemu_plugin_tb
  *  qemu_plugin_insn
  *
  * Which can then be passed back into the API to do additional things.
  * As such all the public functions in here are exported in
  * qemu-plugin.h.
  *
  * The general life-cycle of a plugin is:
  *
  *  - plugin is loaded, public qemu_plugin_install called
  *    - the install func registers callbacks for events
  *    - usually an atexit_cb is registered to dump info at the end
  *  - when a registered event occurs the plugin is called
  *     - some events pass additional info
  *     - during translation the plugin can decide to instrument any
  *       instruction
  *  - when QEMU exits all the registered atexit callbacks are called
  *
  * Copyright (C) 2017, Emilio G. Cota <cota@braap.org>
  * Copyright (C) 2019, Linaro
  *
  * License: GNU GPL, version 2 or later.
  *   See the COPYING file in the top-level directory.
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  *
  */

 #include "qemu/osdep.h"
 #include "qemu/plugin.h"
 #include "cpu.h"
 #include "sysemu/sysemu.h"
 #include "tcg/tcg.h"
 #include "exec/exec-all.h"
 #include "exec/ram_addr.h"
 #include "disas/disas.h"
 #include "plugin.h"
 #ifndef CONFIG_USER_ONLY
 #include "qemu/plugin-memory.h"
 #include "hw/boards.h"
 #endif
 #include "trace/mem.h"

 /* Uninstall and Reset handlers */

 void qemu_plugin_uninstall(qemu_plugin_id_t id, qemu_plugin_simple_cb_t cb)
 {
     plugin_reset_uninstall(id, cb, false);
 }

 void qemu_plugin_reset(qemu_plugin_id_t id, qemu_plugin_simple_cb_t cb)
 {
     plugin_reset_uninstall(id, cb, true);
 }

 /*
  * Plugin Register Functions
  *
  * This allows the plugin to register callbacks for various events
  * during the translation.
  */

 void qemu_plugin_register_vcpu_init_cb(qemu_plugin_id_t id,
                                        qemu_plugin_vcpu_simple_cb_t cb)
 {
     plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_INIT, cb);
 }

 void qemu_plugin_register_vcpu_exit_cb(qemu_plugin_id_t id,
                                        qemu_plugin_vcpu_simple_cb_t cb)
 {
     plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_EXIT, cb);
 }

 void qemu_plugin_register_vcpu_tb_exec_cb(struct qemu_plugin_tb *tb,
                                           qemu_plugin_vcpu_udata_cb_t cb,
                                           enum qemu_plugin_cb_flags flags,
                                           void *udata)
 {
     if (!tb->mem_only) {
         plugin_register_dyn_cb__udata(&tb->cbs[PLUGIN_CB_REGULAR],
                                       cb, flags, udata);
     }
 }

 void qemu_plugin_register_vcpu_tb_exec_inline(struct qemu_plugin_tb *tb,
                                               enum qemu_plugin_op op,
                                               void *ptr, uint64_t imm)
 {
     if (!tb->mem_only) {
         plugin_register_inline_op(&tb->cbs[PLUGIN_CB_INLINE], 0, op, ptr, imm);
     }
 }

 void qemu_plugin_register_vcpu_insn_exec_cb(struct qemu_plugin_insn *insn,
                                             qemu_plugin_vcpu_udata_cb_t cb,
                                             enum qemu_plugin_cb_flags flags,
                                             void *udata)
 {
     if (!insn->mem_only) {
         plugin_register_dyn_cb__udata(&insn->cbs[PLUGIN_CB_INSN][PLUGIN_CB_REGULAR],
                                       cb, flags, udata);
     }
 }

 void qemu_plugin_register_vcpu_insn_exec_inline(struct qemu_plugin_insn *insn,
                                                 enum qemu_plugin_op op,
                                                 void *ptr, uint64_t imm)
 {
     if (!insn->mem_only) {
         plugin_register_inline_op(&insn->cbs[PLUGIN_CB_INSN][PLUGIN_CB_INLINE],
                                   0, op, ptr, imm);
     }
 }


 /*
  * We always plant memory instrumentation because they don't finalise until
  * after the operation has complete.
  */
 void qemu_plugin_register_vcpu_mem_cb(struct qemu_plugin_insn *insn,
                                       qemu_plugin_vcpu_mem_cb_t cb,
                                       enum qemu_plugin_cb_flags flags,
                                       enum qemu_plugin_mem_rw rw,
                                       void *udata)
 {
     plugin_register_vcpu_mem_cb(&insn->cbs[PLUGIN_CB_MEM][PLUGIN_CB_REGULAR],
                                     cb, flags, rw, udata);
 }

 void qemu_plugin_register_vcpu_mem_inline(struct qemu_plugin_insn *insn,
                                           enum qemu_plugin_mem_rw rw,
                                           enum qemu_plugin_op op, void *ptr,
                                           uint64_t imm)
 {
     plugin_register_inline_op(&insn->cbs[PLUGIN_CB_MEM][PLUGIN_CB_INLINE],
                               rw, op, ptr, imm);
 }

 void qemu_plugin_register_vcpu_tb_trans_cb(qemu_plugin_id_t id,
                                            qemu_plugin_vcpu_tb_trans_cb_t cb)
 {
     plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_TB_TRANS, cb);
 }

 void qemu_plugin_register_vcpu_syscall_cb(qemu_plugin_id_t id,
                                           qemu_plugin_vcpu_syscall_cb_t cb)
 {
     plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_SYSCALL, cb);
 }

 void
 qemu_plugin_register_vcpu_syscall_ret_cb(qemu_plugin_id_t id,
                                          qemu_plugin_vcpu_syscall_ret_cb_t cb)
 {
     plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_SYSCALL_RET, cb);
 }

 /*
  * Plugin Queries
  *
  * These are queries that the plugin can make to gauge information
  * from our opaque data types. We do not want to leak internal details
  * here just information useful to the plugin.
  */

 /*
  * Translation block information:
  *
  * A plugin can query the virtual address of the start of the block
  * and the number of instructions in it. It can also get access to
  * each translated instruction.
  */

 size_t qemu_plugin_tb_n_insns(const struct qemu_plugin_tb *tb)
 {
     return tb->n;
 }

 uint64_t qemu_plugin_tb_vaddr(const struct qemu_plugin_tb *tb)
 {
     return tb->vaddr;
 }

 struct qemu_plugin_insn *
 qemu_plugin_tb_get_insn(const struct qemu_plugin_tb *tb, size_t idx)
 {
     struct qemu_plugin_insn *insn;
     if (unlikely(idx >= tb->n)) {
         return NULL;
     }
     insn = g_ptr_array_index(tb->insns, idx);
     insn->mem_only = tb->mem_only;
     return insn;
 }

 /*
  * Instruction information
  *
  * These queries allow the plugin to retrieve information about each
  * instruction being translated.
  */

 const void *qemu_plugin_insn_data(const struct qemu_plugin_insn *insn)
 {
     return insn->data->data;
 }

 size_t qemu_plugin_insn_size(const struct qemu_plugin_insn *insn)
 {
     return insn->data->len;
 }

 uint64_t qemu_plugin_insn_vaddr(const struct qemu_plugin_insn *insn)
 {
     return insn->vaddr;
 }

 void *qemu_plugin_insn_haddr(const struct qemu_plugin_insn *insn)
 {
     return insn->haddr;
 }

 char *qemu_plugin_insn_disas(const struct qemu_plugin_insn *insn)
 {
     CPUState *cpu = current_cpu;
     return plugin_disas(cpu, insn->vaddr, insn->data->len);
 }

 /*
  * The memory queries allow the plugin to query information about a
  * memory access.
  */

 unsigned qemu_plugin_mem_size_shift(qemu_plugin_meminfo_t info)
 {
     return info & TRACE_MEM_SZ_SHIFT_MASK;
 }

 bool qemu_plugin_mem_is_sign_extended(qemu_plugin_meminfo_t info)
 {
     return !!(info & TRACE_MEM_SE);
 }

 bool qemu_plugin_mem_is_big_endian(qemu_plugin_meminfo_t info)
 {
     return !!(info & TRACE_MEM_BE);
 }

 bool qemu_plugin_mem_is_store(qemu_plugin_meminfo_t info)
 {
     return !!(info & TRACE_MEM_ST);
 }

 /*
  * Virtual Memory queries
  */

 #ifdef CONFIG_SOFTMMU
 static __thread struct qemu_plugin_hwaddr hwaddr_info;
 #endif

 struct qemu_plugin_hwaddr *qemu_plugin_get_hwaddr(qemu_plugin_meminfo_t info,
                                                   uint64_t vaddr)
 {
 #ifdef CONFIG_SOFTMMU
     CPUState *cpu = current_cpu;
     unsigned int mmu_idx = info >> TRACE_MEM_MMU_SHIFT;
     hwaddr_info.is_store = info & TRACE_MEM_ST;

     if (!tlb_plugin_lookup(cpu, vaddr, mmu_idx,
                            info & TRACE_MEM_ST, &hwaddr_info)) {
         error_report("invalid use of qemu_plugin_get_hwaddr");
         return NULL;
     }

     return &hwaddr_info;
 #else
     return NULL;
 #endif
 }

 bool qemu_plugin_hwaddr_is_io(const struct qemu_plugin_hwaddr *haddr)
 {
 #ifdef CONFIG_SOFTMMU
     return haddr->is_io;
 #else
     return false;
 #endif
 }

 uint64_t qemu_plugin_hwaddr_phys_addr(const struct qemu_plugin_hwaddr *haddr)
 {
 #ifdef CONFIG_SOFTMMU
     if (haddr) {
         if (!haddr->is_io) {
             RAMBlock *block;
             ram_addr_t offset;
             void *hostaddr = (void *) haddr->v.ram.hostaddr;

             block = qemu_ram_block_from_host(hostaddr, false, &offset);
             if (!block) {
                 error_report("Bad ram pointer %"PRIx64"", haddr->v.ram.hostaddr);
                 abort();
             }

             return block->offset + offset + block->mr->addr;
         } else {
             MemoryRegionSection *mrs = haddr->v.io.section;
             return haddr->v.io.offset + mrs->mr->addr;
         }
     }
 #endif
     return 0;
 }

 const char *qemu_plugin_hwaddr_device_name(const struct qemu_plugin_hwaddr *h)
 {
 #ifdef CONFIG_SOFTMMU
     if (h && h->is_io) {
         MemoryRegionSection *mrs = h->v.io.section;
         if (!mrs->mr->name) {
             unsigned long maddr = 0xffffffff & (uintptr_t) mrs->mr;
             g_autofree char *temp = g_strdup_printf("anon%08lx", maddr);
             return g_intern_string(temp);
         } else {
             return g_intern_string(mrs->mr->name);
         }
     } else {
         return g_intern_static_string("RAM");
     }
 #else
     return g_intern_static_string("Invalid");
 #endif
 }

 /*
  * Queries to the number and potential maximum number of vCPUs there
  * will be. This helps the plugin dimension per-vcpu arrays.
  */

 #ifndef CONFIG_USER_ONLY
 static MachineState * get_ms(void)
 {
     return MACHINE(qdev_get_machine());
 }
 #endif

 int qemu_plugin_n_vcpus(void)
 {
 #ifdef CONFIG_USER_ONLY
     return -1;
 #else
     return get_ms()->smp.cpus;
 #endif
 }

 int qemu_plugin_n_max_vcpus(void)
 {
 #ifdef CONFIG_USER_ONLY
     return -1;
 #else
     return get_ms()->smp.max_cpus;
 #endif
 }

 /*
  * Plugin output
  */
 void qemu_plugin_outs(const char *string)
 {
     qemu_log_mask(CPU_LOG_PLUGIN, "%s", string);
 }
	/*
	* QEMU Plugin API
	*
	* This provides the API that is available to the plugins to interact
	* with QEMU. We have to be careful not to expose internal details of
	* how QEMU works so we abstract out things like translation and
	* instructions to anonymous data types:
	*
	* qemu_plugin_tb
	* qemu_plugin_insn
	*
	* Which can then be passed back into the API to do additional things.
	* As such all the public functions in here are exported in
	* qemu-plugin.h.
	*
	* The general life-cycle of a plugin is:
	*
	* - plugin is loaded, public qemu_plugin_install called
	* - the install func registers callbacks for events
	* - usually an atexit_cb is registered to dump info at the end
	* - when a registered event occurs the plugin is called
	* - some events pass additional info
	* - during translation the plugin can decide to instrument any
	* instruction
	* - when QEMU exits all the registered atexit callbacks are called
	*
	* Copyright (C) 2017, Emilio G. Cota <cota@braap.org>
	* Copyright (C) 2019, Linaro
	*
	* License: GNU GPL, version 2 or later.
	* See the COPYING file in the top-level directory.
	*
	* SPDX-License-Identifier: GPL-2.0-or-later
	*
	*/

	#include "qemu/osdep.h"
	#include "qemu/plugin.h"
	#include "cpu.h"
	#include "sysemu/sysemu.h"
	#include "tcg/tcg.h"
	#include "exec/exec-all.h"
	#include "exec/ram_addr.h"
	#include "disas/disas.h"
	#include "plugin.h"
	#ifndef CONFIG_USER_ONLY
	#include "qemu/plugin-memory.h"
	#include "hw/boards.h"
	#endif
	#include "trace/mem.h"

	/* Uninstall and Reset handlers */

	void qemu_plugin_uninstall(qemu_plugin_id_t id, qemu_plugin_simple_cb_t cb)
	{
	plugin_reset_uninstall(id, cb, false);
	}

	void qemu_plugin_reset(qemu_plugin_id_t id, qemu_plugin_simple_cb_t cb)
	{
	plugin_reset_uninstall(id, cb, true);
	}

	/*
	* Plugin Register Functions
	*
	* This allows the plugin to register callbacks for various events
	* during the translation.
	*/

	void qemu_plugin_register_vcpu_init_cb(qemu_plugin_id_t id,
	qemu_plugin_vcpu_simple_cb_t cb)
	{
	plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_INIT, cb);
	}

	void qemu_plugin_register_vcpu_exit_cb(qemu_plugin_id_t id,
	qemu_plugin_vcpu_simple_cb_t cb)
	{
	plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_EXIT, cb);
	}

	void qemu_plugin_register_vcpu_tb_exec_cb(struct qemu_plugin_tb *tb,
	qemu_plugin_vcpu_udata_cb_t cb,
	enum qemu_plugin_cb_flags flags,
	void *udata)
	{
	if (!tb->mem_only) {
	plugin_register_dyn_cb__udata(&tb->cbs[PLUGIN_CB_REGULAR],
	cb, flags, udata);
	}
	}

	void qemu_plugin_register_vcpu_tb_exec_inline(struct qemu_plugin_tb *tb,
	enum qemu_plugin_op op,
	void *ptr, uint64_t imm)
	{
	if (!tb->mem_only) {
	plugin_register_inline_op(&tb->cbs[PLUGIN_CB_INLINE], 0, op, ptr, imm);
	}
	}

	void qemu_plugin_register_vcpu_insn_exec_cb(struct qemu_plugin_insn *insn,
	qemu_plugin_vcpu_udata_cb_t cb,
	enum qemu_plugin_cb_flags flags,
	void *udata)
	{
	if (!insn->mem_only) {
	plugin_register_dyn_cb__udata(&insn->cbs[PLUGIN_CB_INSN][PLUGIN_CB_REGULAR],
	cb, flags, udata);
	}
	}

	void qemu_plugin_register_vcpu_insn_exec_inline(struct qemu_plugin_insn *insn,
	enum qemu_plugin_op op,
	void *ptr, uint64_t imm)
	{
	if (!insn->mem_only) {
	plugin_register_inline_op(&insn->cbs[PLUGIN_CB_INSN][PLUGIN_CB_INLINE],
	0, op, ptr, imm);
	}
	}


	/*
	* We always plant memory instrumentation because they don't finalise until
	* after the operation has complete.
	*/
	void qemu_plugin_register_vcpu_mem_cb(struct qemu_plugin_insn *insn,
	qemu_plugin_vcpu_mem_cb_t cb,
	enum qemu_plugin_cb_flags flags,
	enum qemu_plugin_mem_rw rw,
	void *udata)
	{
	plugin_register_vcpu_mem_cb(&insn->cbs[PLUGIN_CB_MEM][PLUGIN_CB_REGULAR],
	cb, flags, rw, udata);
	}

	void qemu_plugin_register_vcpu_mem_inline(struct qemu_plugin_insn *insn,
	enum qemu_plugin_mem_rw rw,
	enum qemu_plugin_op op, void *ptr,
	uint64_t imm)
	{
	plugin_register_inline_op(&insn->cbs[PLUGIN_CB_MEM][PLUGIN_CB_INLINE],
	rw, op, ptr, imm);
	}

	void qemu_plugin_register_vcpu_tb_trans_cb(qemu_plugin_id_t id,
	qemu_plugin_vcpu_tb_trans_cb_t cb)
	{
	plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_TB_TRANS, cb);
	}

	void qemu_plugin_register_vcpu_syscall_cb(qemu_plugin_id_t id,
	qemu_plugin_vcpu_syscall_cb_t cb)
	{
	plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_SYSCALL, cb);
	}

	void
	qemu_plugin_register_vcpu_syscall_ret_cb(qemu_plugin_id_t id,
	qemu_plugin_vcpu_syscall_ret_cb_t cb)
	{
	plugin_register_cb(id, QEMU_PLUGIN_EV_VCPU_SYSCALL_RET, cb);
	}

	/*
	* Plugin Queries
	*
	* These are queries that the plugin can make to gauge information
	* from our opaque data types. We do not want to leak internal details
	* here just information useful to the plugin.
	*/

	/*
	* Translation block information:
	*
	* A plugin can query the virtual address of the start of the block
	* and the number of instructions in it. It can also get access to
	* each translated instruction.
	*/

	size_t qemu_plugin_tb_n_insns(const struct qemu_plugin_tb *tb)
	{
	return tb->n;
	}

	uint64_t qemu_plugin_tb_vaddr(const struct qemu_plugin_tb *tb)
	{
	return tb->vaddr;
	}

	struct qemu_plugin_insn *
	qemu_plugin_tb_get_insn(const struct qemu_plugin_tb *tb, size_t idx)
	{
	struct qemu_plugin_insn *insn;
	if (unlikely(idx >= tb->n)) {
	return NULL;
	}
	insn = g_ptr_array_index(tb->insns, idx);
	insn->mem_only = tb->mem_only;
	return insn;
	}

	/*
	* Instruction information
	*
	* These queries allow the plugin to retrieve information about each
	* instruction being translated.
	*/

	const void qemu_plugin_insn_data(const struct qemu_plugin_insn insn)
	{
	return insn->data->data;
	}

	size_t qemu_plugin_insn_size(const struct qemu_plugin_insn *insn)
	{
	return insn->data->len;
	}

	uint64_t qemu_plugin_insn_vaddr(const struct qemu_plugin_insn *insn)
	{
	return insn->vaddr;
	}

	void qemu_plugin_insn_haddr(const struct qemu_plugin_insn insn)
	{
	return insn->haddr;
	}

	char qemu_plugin_insn_disas(const struct qemu_plugin_insn insn)
	{
	CPUState *cpu = current_cpu;
	return plugin_disas(cpu, insn->vaddr, insn->data->len);
	}

	/*
	* The memory queries allow the plugin to query information about a
	* memory access.
	*/

	unsigned qemu_plugin_mem_size_shift(qemu_plugin_meminfo_t info)
	{
	return info & TRACE_MEM_SZ_SHIFT_MASK;
	}

	bool qemu_plugin_mem_is_sign_extended(qemu_plugin_meminfo_t info)
	{
	return !!(info & TRACE_MEM_SE);
	}

	bool qemu_plugin_mem_is_big_endian(qemu_plugin_meminfo_t info)
	{
	return !!(info & TRACE_MEM_BE);
	}

	bool qemu_plugin_mem_is_store(qemu_plugin_meminfo_t info)
	{
	return !!(info & TRACE_MEM_ST);
	}

	/*
	* Virtual Memory queries
	*/

	#ifdef CONFIG_SOFTMMU
	static __thread struct qemu_plugin_hwaddr hwaddr_info;
	#endif

	struct qemu_plugin_hwaddr *qemu_plugin_get_hwaddr(qemu_plugin_meminfo_t info,
	uint64_t vaddr)
	{
	#ifdef CONFIG_SOFTMMU
	CPUState *cpu = current_cpu;
	unsigned int mmu_idx = info >> TRACE_MEM_MMU_SHIFT;
	hwaddr_info.is_store = info & TRACE_MEM_ST;

	if (!tlb_plugin_lookup(cpu, vaddr, mmu_idx,
	info & TRACE_MEM_ST, &hwaddr_info)) {
	error_report("invalid use of qemu_plugin_get_hwaddr");
	return NULL;
	}

	return &hwaddr_info;
	#else
	return NULL;
	#endif
	}

	bool qemu_plugin_hwaddr_is_io(const struct qemu_plugin_hwaddr *haddr)
	{
	#ifdef CONFIG_SOFTMMU
	return haddr->is_io;
	#else
	return false;
	#endif
	}

	uint64_t qemu_plugin_hwaddr_phys_addr(const struct qemu_plugin_hwaddr *haddr)
	{
	#ifdef CONFIG_SOFTMMU
	if (haddr) {
	if (!haddr->is_io) {
	RAMBlock *block;
	ram_addr_t offset;
	void hostaddr = (void ) haddr->v.ram.hostaddr;

	block = qemu_ram_block_from_host(hostaddr, false, &offset);
	if (!block) {
	error_report("Bad ram pointer %"PRIx64"", haddr->v.ram.hostaddr);
	abort();
	}

	return block->offset + offset + block->mr->addr;
	} else {
	MemoryRegionSection *mrs = haddr->v.io.section;
	return haddr->v.io.offset + mrs->mr->addr;
	}
	}
	#endif
	return 0;
	}

	const char qemu_plugin_hwaddr_device_name(const struct qemu_plugin_hwaddr h)
	{
	#ifdef CONFIG_SOFTMMU
	if (h && h->is_io) {
	MemoryRegionSection *mrs = h->v.io.section;
	if (!mrs->mr->name) {
	unsigned long maddr = 0xffffffff & (uintptr_t) mrs->mr;
	g_autofree char *temp = g_strdup_printf("anon%08lx", maddr);
	return g_intern_string(temp);
	} else {
	return g_intern_string(mrs->mr->name);
	}
	} else {
	return g_intern_static_string("RAM");
	}
	#else
	return g_intern_static_string("Invalid");
	#endif
	}

	/*
	* Queries to the number and potential maximum number of vCPUs there
	* will be. This helps the plugin dimension per-vcpu arrays.
	*/

	#ifndef CONFIG_USER_ONLY
	static MachineState * get_ms(void)
	{
	return MACHINE(qdev_get_machine());
	}
	#endif

	int qemu_plugin_n_vcpus(void)
	{
	#ifdef CONFIG_USER_ONLY
	return -1;
	#else
	return get_ms()->smp.cpus;
	#endif
	}

	int qemu_plugin_n_max_vcpus(void)
	{
	#ifdef CONFIG_USER_ONLY
	return -1;
	#else
	return get_ms()->smp.max_cpus;
	#endif
	}

	/*
	* Plugin output
	*/
	void qemu_plugin_outs(const char *string)
	{
	qemu_log_mask(CPU_LOG_PLUGIN, "%s", string);
	}