Give the plugins access to the QEMU dissasembler so they don't have to
re-invent the wheel.
Signed-off-by: Alex Bennée <alex.ben...@linaro.org>
---
disas.c | 103 +++++++++++++++++++++++++++++++++++
include/disas/disas.h | 2 +
include/qemu/qemu-plugin.h | 9 +++
plugins/api.c | 7 +++
plugins/qemu-plugins.symbols | 1 +
5 files changed, 122 insertions(+)
diff --git a/disas.c b/disas.c
index 3e2bfa572b..d8b75f0b73 100644
--- a/disas.c
+++ b/disas.c
@@ -475,6 +475,109 @@ void target_disas(FILE *out, CPUState *cpu, target_ulong
code,
}
}
+static GString plugin_disas_output;
+
+static int plugin_printf(FILE *stream, const char *fmt, ...)
+{
+ va_list va;
+ GString *s = &plugin_disas_output;
+ int initial_len = s->len;
+
+ va_start(va, fmt);
+ g_string_append_printf(s, fmt, va);
+ va_end(va);
+
+ return s->len - initial_len;
+}
+
+static void plugin_print_address (bfd_vma addr, struct disassemble_info *info)
+{
+ /* does nothing */
+}
+
+/* Disassemble a single instruction directly into plugin output */
+static bool plugin_cap_disas_insn(disassemble_info *info, uint64_t pc, size_t
size)
+{
+ uint8_t cap_buf[1024];
+ csh handle;
+ cs_insn *insn;
+ size_t csize = 0;
+ int count;
+ GString *s = &plugin_disas_output;
+
+ if (cap_disas_start(info, &handle) != CS_ERR_OK) {
+ return false;
+ }
+ insn = cap_insn;
+
+ size_t tsize = MIN(sizeof(cap_buf) - csize, size);
+ const uint8_t *cbuf = cap_buf;
+ target_read_memory(pc, cap_buf, tsize, info);
+
+ count = cs_disasm(handle, cbuf, size, 0, 1, &insn);
+
+ if (count) {
+ g_string_printf(s, "%s %s", insn->mnemonic, insn->op_str);
+ } else {
+ g_string_printf(s, "cs_disasm failed");
+ }
+
+ cs_close(&handle);
+ return true;
+}
+
+char * plugin_disas(CPUState *cpu, uint64_t addr, size_t size)
+{
+ CPUClass *cc = CPU_GET_CLASS(cpu);
+ target_ulong pc;
+ int count;
+ CPUDebug s;
+ GString *ds = g_string_set_size(&plugin_disas_output, 0);
+
+ g_assert(ds == &plugin_disas_output);
+
+ INIT_DISASSEMBLE_INFO(s.info, NULL, plugin_printf);
+
+ s.cpu = cpu;
+ s.info.read_memory_func = target_read_memory;
+ s.info.buffer_vma = addr;
+ s.info.buffer_length = size;
+ s.info.print_address_func = plugin_print_address;
+ s.info.cap_arch = -1;
+ s.info.cap_mode = 0;
+ s.info.cap_insn_unit = 4;
+ s.info.cap_insn_split = 4;
+
+#ifdef TARGET_WORDS_BIGENDIAN
+ s.info.endian = BFD_ENDIAN_BIG;
+#else
+ s.info.endian = BFD_ENDIAN_LITTLE;
+#endif
+
+ if (cc->disas_set_info) {
+ cc->disas_set_info(cpu, &s.info);
+ }
+
+ if (s.info.cap_arch >= 0 && plugin_cap_disas_insn(&s.info, addr, size)) {
+ return g_strdup(ds->str);
+ }
+
+ if (s.info.print_insn == NULL) {
+ s.info.print_insn = print_insn_od_target;
+ }
+
+ for (pc = addr; size > 0; pc += count, size -= count) {
+ count = s.info.print_insn(pc, &s.info);
+
+ if (count < 0)
+ break;
+
+ g_assert(size >= count);
+ }
+
+ return g_strdup(ds->str);
+}
+
/* Disassemble this for me please... (debugging). */
void disas(FILE *out, void *code, unsigned long size)
{
diff --git a/include/disas/disas.h b/include/disas/disas.h
index 15da511f49..119df9e9bd 100644
--- a/include/disas/disas.h
+++ b/include/disas/disas.h
@@ -13,6 +13,8 @@ void target_disas(FILE *out, CPUState *cpu, target_ulong code,
void monitor_disas(Monitor *mon, CPUState *cpu,
target_ulong pc, int nb_insn, int is_physical);
+char * plugin_disas(CPUState *cpu, uint64_t addr, size_t size);
+
/* Look up symbol for debugging purpose. Returns "" if unknown. */
const char *lookup_symbol(target_ulong orig_addr);
#endif
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index 0db1ef9714..21f056d4ab 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -312,6 +312,15 @@ qemu_plugin_register_vcpu_syscall_ret_cb(qemu_plugin_id_t
id,
qemu_plugin_vcpu_syscall_ret_cb_t cb);
+/**
+ * qemu_plugin_insn_disas() - return disassembly string for instruction
+ * @insn: instruction reference
+ *
+ * Returns an allocated string containing the disassembly
+ */
+
+char * qemu_plugin_insn_disas(const struct qemu_plugin_insn *insn);
+
/**
* qemu_plugin_vcpu_for_each() - iterate over the existing vCPU
* @id: plugin ID
diff --git a/plugins/api.c b/plugins/api.c
index 1c3aa64702..c0a1e98e68 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -40,6 +40,7 @@
#include "sysemu/sysemu.h"
#include "tcg/tcg.h"
#include "trace/mem-internal.h" /* mem_info macros */
+#include "disas/disas.h"
#include "plugin.h"
/* Uninstall and Reset handlers */
@@ -218,6 +219,12 @@ 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.
diff --git a/plugins/qemu-plugins.symbols b/plugins/qemu-plugins.symbols
index 38d47b7922..3fd51112b5 100644
--- a/plugins/qemu-plugins.symbols
+++ b/plugins/qemu-plugins.symbols
@@ -25,6 +25,7 @@
qemu_plugin_insn_size;
qemu_plugin_insn_vaddr;
qemu_plugin_insn_haddr;
+ qemu_plugin_insn_disas;
qemu_plugin_mem_size_shift;
qemu_plugin_mem_is_sign_extended;
qemu_plugin_mem_is_big_endian;
--
2.20.1
