[Qemu-devel] [PATCH v4] cpu: add suboptions support

[Alexey Kardashevskiy <aik@ozlabs.ru>]

This adds suboptions support for -cpu. This keeps @cpu_model in order not
to break the existing architectures/machines.

Cc: Andreas Färber <afaerber@suse.de>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
Changes:
v4:
* moved QemuOpts logic to qeom/cpu.c
* added cpu_opt_get() as the machine init code wants to know the CPU name
to create a CPU object
---
 include/qom/cpu.h | 41 +++++++++++++++++++++++++++++++++++++++++
 qom/cpu.c         | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 vl.c              | 23 +++++++++++++++++++++++
 3 files changed, 113 insertions(+)

diff --git a/include/qom/cpu.h b/include/qom/cpu.h
index 7739e00..07330e1 100644
--- a/include/qom/cpu.h
+++ b/include/qom/cpu.h
@@ -124,6 +124,7 @@ typedef struct CPUClass {
                             int cpuid, void *opaque);
     int (*write_elf32_qemunote)(WriteCoreDumpFunction f, CPUState *cpu,
                                 void *opaque);
+    void (*parse_options)(CPUState *cpu, Error **errp);
 
     const struct VMStateDescription *vmsd;
     int gdb_num_core_regs;
@@ -327,6 +328,46 @@ static inline hwaddr cpu_get_phys_page_debug(CPUState *cpu, vaddr addr)
 #endif
 
 /**
+ * cpu_parse_options:
+ * @cpu: The CPU to set options for.
+ *
+ * Parses CPU options if the CPU class has a custom handler defined.
+ *
+ * Returns: -1 if a custom handler is defined and failed, 0 otherwise.
+ */
+static inline int cpu_parse_options(CPUState *cpu)
+{
+    CPUClass *cc = CPU_GET_CLASS(cpu);
+    Error *err = NULL;
+
+    if (cc->parse_options) {
+        cc->parse_options(cpu, &err);
+        if (err) {
+            return -1;
+        }
+    }
+
+    /* No callback, let arch do it the old way */
+    return 0;
+}
+
+/**
+ * cpu_default_parse_options_func:
+ * The default handler for CPUClass::parse_options
+ * @cpu: the CPU to set option for.
+ * @errp: the handling error descriptor.
+ */
+void cpu_default_parse_options_func(CPUState *cpu, Error **errp);
+
+/**
+ * cpu_get_opt:
+ * @name: The parameter name
+ *
+ * Returns: a CPU parameter value.
+ */
+const char *cpu_opt_get(const char *name);
+
+/**
  * cpu_reset:
  * @cpu: The CPU whose state is to be reset.
  */
diff --git a/qom/cpu.c b/qom/cpu.c
index 818fb26..fb95cb4 100644
--- a/qom/cpu.c
+++ b/qom/cpu.c
@@ -24,6 +24,8 @@
 #include "qemu/notify.h"
 #include "qemu/log.h"
 #include "sysemu/sysemu.h"
+#include "qapi/qmp/qerror.h"
+#include "qemu/config-file.h"
 
 bool cpu_exists(int64_t id)
 {
@@ -273,3 +275,50 @@ static void cpu_register_types(void)
 }
 
 type_init(cpu_register_types)
+
+static int cpu_set_property(const char *name, const char *value, void *opaque)
+{
+    Error *err = NULL;
+
+    if (strcmp(name, "type") == 0) {
+        return 0;
+    }
+
+    object_property_parse(opaque, value, name, &err);
+    if (err != NULL) {
+        qerror_report_err(err);
+        error_free(err);
+        return -1;
+    }
+
+    return 0;
+}
+
+static QemuOpts *cpu_get_opts(void)
+{
+    QemuOptsList *list;
+
+    list = qemu_find_opts("cpu");
+    assert(list);
+    return qemu_opts_find(list, NULL);
+}
+
+void cpu_default_parse_options_func(CPUState *cpu, Error **errp)
+{
+    QemuOpts *opts = cpu_get_opts();
+
+    if (opts && qemu_opt_foreach(opts, cpu_set_property, cpu, 1)) {
+        error_setg(errp, "Bad option");
+    }
+}
+
+const char *cpu_opt_get(const char *name)
+{
+    QemuOpts *opts = cpu_get_opts();
+
+    if (!opts) {
+        return NULL;
+    }
+
+    return qemu_opt_get(cpu_get_opts(), name);
+}
diff --git a/vl.c b/vl.c
index 8d5d874..f7c4c0a 100644
--- a/vl.c
+++ b/vl.c
@@ -433,6 +433,16 @@ static QemuOptsList qemu_machine_opts = {
     },
 };
 
+static QemuOptsList qemu_cpu_opts = {
+    .name = "cpu",
+    .implied_opt_name = "type",
+    .merge_lists = true,
+    .head = QTAILQ_HEAD_INITIALIZER(qemu_cpu_opts.head),
+    .desc = {
+        { /* End of list */ }
+    },
+};
+
 static QemuOptsList qemu_boot_opts = {
     .name = "boot-opts",
     .implied_opt_name = "order",
@@ -2880,6 +2890,7 @@ int main(int argc, char **argv, char **envp)
     qemu_add_opts(&qemu_trace_opts);
     qemu_add_opts(&qemu_option_rom_opts);
     qemu_add_opts(&qemu_machine_opts);
+    qemu_add_opts(&qemu_cpu_opts);
     qemu_add_opts(&qemu_smp_opts);
     qemu_add_opts(&qemu_boot_opts);
     qemu_add_opts(&qemu_sandbox_opts);
@@ -2975,7 +2986,19 @@ int main(int argc, char **argv, char **envp)
             }
             case QEMU_OPTION_cpu:
                 /* hw initialization will check this */
+
+                /* Store cpu_model for old style parser */
                 cpu_model = optarg;
+
+                /*
+                 * Parse and save options in the cpu options list
+                 * for a new parser
+                 */
+                olist = qemu_find_opts("cpu");
+                opts = qemu_opts_parse(olist, optarg, 1);
+                if (!opts) {
+                    exit(1);
+                }
                 break;
             case QEMU_OPTION_hda:
                 {
-- 
1.8.4.rc4