@@ -54,6 +54,20 @@
#define co_wrapper_bdrv_rdlock no_coroutine_fn
#define co_wrapper_mixed_bdrv_rdlock no_coroutine_fn coroutine_mixed_fn
+/*
+ * no_co_wrapper: Function specifier used by block-coroutine-wrapper.py
+ *
+ * Function specifier which does nothing but mark functions to be generated by
+ * scripts/block-coroutine-wrapper.py.
+ *
+ * A no_co_wrapper function declaration creates a coroutine_fn wrapper around
+ * functions that must not be called in coroutine context. It achieves this by
+ * scheduling a BH in the bottom half that runs the respective non-coroutine
+ * function. The coroutine yields after scheduling the BH and is reentered when
+ * the wrapped function returns.
+ */
+#define no_co_wrapper
+
#include "block/blockjob.h"
/* block.c */
@@ -63,8 +63,8 @@ def __init__(self, param_decl: str) -> None:
class FuncDecl:
- def __init__(self, return_type: str, name: str, args: str,
- variant: str) -> None:
+ def __init__(self, wrapper_type: str, return_type: str, name: str,
+ args: str, variant: str) -> None:
self.return_type = return_type.strip()
self.name = name.strip()
self.struct_name = snake_to_camel(self.name)
@@ -72,8 +72,21 @@ def __init__(self, return_type: str, name: str, args: str,
self.create_only_co = 'mixed' not in variant
self.graph_rdlock = 'bdrv_rdlock' in variant
- subsystem, subname = self.name.split('_', 1)
- self.co_name = f'{subsystem}_co_{subname}'
+ self.wrapper_type = wrapper_type
+
+ if wrapper_type == 'co':
+ subsystem, subname = self.name.split('_', 1)
+ self.target_name = f'{subsystem}_co_{subname}'
+ else:
+ assert wrapper_type == 'no_co'
+ subsystem, co_infix, subname = self.name.split('_', 2)
+ if co_infix != 'co':
+ raise ValueError(f"Invalid no_co function name: {self.name}")
+ if not self.create_only_co:
+ raise ValueError(f"no_co function can't be mixed: {self.name}")
+ if self.graph_rdlock:
+ raise ValueError(f"no_co function can't be rdlock: {self.name}")
+ self.target_name = f'{subsystem}_{subname}'
t = self.args[0].type
if t == 'BlockDriverState *':
@@ -105,7 +118,8 @@ def gen_block(self, format: str) -> str:
# Match wrappers declared with a co_wrapper mark
func_decl_re = re.compile(r'^(?P<return_type>[a-zA-Z][a-zA-Z0-9_]* [\*]?)'
- r'\s*co_wrapper'
+ r'(\s*coroutine_fn)?'
+ r'\s*(?P<wrapper_type>(no_)?co)_wrapper'
r'(?P<variant>(_[a-z][a-z0-9_]*)?)\s*'
r'(?P<wrapper_name>[a-z][a-z0-9_]*)'
r'\((?P<args>[^)]*)\);$', re.MULTILINE)
@@ -113,7 +127,8 @@ def gen_block(self, format: str) -> str:
def func_decl_iter(text: str) -> Iterator:
for m in func_decl_re.finditer(text):
- yield FuncDecl(return_type=m.group('return_type'),
+ yield FuncDecl(wrapper_type=m.group('wrapper_type'),
+ return_type=m.group('return_type'),
name=m.group('wrapper_name'),
args=m.group('args'),
variant=m.group('variant'))
@@ -133,7 +148,7 @@ def create_mixed_wrapper(func: FuncDecl) -> str:
"""
Checks if we are already in coroutine
"""
- name = func.co_name
+ name = func.target_name
struct_name = func.struct_name
graph_assume_lock = 'assume_graph_lock();' if func.graph_rdlock else ''
@@ -163,7 +178,7 @@ def create_co_wrapper(func: FuncDecl) -> str:
"""
Assumes we are not in coroutine, and creates one
"""
- name = func.co_name
+ name = func.target_name
struct_name = func.struct_name
return f"""\
{func.return_type} {func.name}({ func.gen_list('{decl}') })
@@ -183,10 +198,11 @@ def create_co_wrapper(func: FuncDecl) -> str:
}}"""
-def gen_wrapper(func: FuncDecl) -> str:
+def gen_co_wrapper(func: FuncDecl) -> str:
assert not '_co_' in func.name
+ assert func.wrapper_type == 'co'
- name = func.co_name
+ name = func.target_name
struct_name = func.struct_name
graph_lock=''
@@ -225,11 +241,56 @@ def gen_wrapper(func: FuncDecl) -> str:
{creation_function(func)}"""
+def gen_no_co_wrapper(func: FuncDecl) -> str:
+ assert '_co_' in func.name
+ assert func.wrapper_type == 'no_co'
+
+ name = func.target_name
+ struct_name = func.struct_name
+
+ return f"""\
+/*
+ * Wrappers for {name}
+ */
+
+typedef struct {struct_name} {{
+ Coroutine *co;
+ {func.return_field}
+{ func.gen_block(' {decl};') }
+}} {struct_name};
+
+static void {name}_bh(void *opaque)
+{{
+ {struct_name} *s = opaque;
+
+ {func.get_result}{name}({ func.gen_list('s->{name}') });
+
+ aio_co_wake(s->co);
+}}
+
+{func.return_type} coroutine_fn {func.name}({ func.gen_list('{decl}') })
+{{
+ {struct_name} s = {{
+ .co = qemu_coroutine_self(),
+{ func.gen_block(' .{name} = {name},') }
+ }};
+ assert(qemu_in_coroutine());
+
+ aio_bh_schedule_oneshot(qemu_get_aio_context(), {name}_bh, &s);
+ qemu_coroutine_yield();
+
+ {func.ret}
+}}"""
+
+
def gen_wrappers(input_code: str) -> str:
res = ''
for func in func_decl_iter(input_code):
res += '\n\n\n'
- res += gen_wrapper(func)
+ if func.wrapper_type == 'co':
+ res += gen_co_wrapper(func)
+ else:
+ res += gen_no_co_wrapper(func)
return res