qemu-patch-raspberry4/include/exec/user/thunk.h
Markus Armbruster ec150c7e09 include: Make headers more self-contained
Back in 2016, we discussed[1] rules for headers, and these were
generally liked:

1. Have a carefully curated header that's included everywhere first.  We
   got that already thanks to Peter: osdep.h.

2. Headers should normally include everything they need beyond osdep.h.
   If exceptions are needed for some reason, they must be documented in
   the header.  If all that's needed from a header is typedefs, put
   those into qemu/typedefs.h instead of including the header.

3. Cyclic inclusion is forbidden.

This patch gets include/ closer to obeying 2.

It's actually extracted from my "[RFC] Baby steps towards saner
headers" series[2], which demonstrates a possible path towards
checking 2 automatically.  It passes the RFC test there.

[1] Message-ID: <87h9g8j57d.fsf@blackfin.pond.sub.org>
    https://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg03345.html
[2] Message-Id: <20190711122827.18970-1-armbru@redhat.com>
    https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg02715.html

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-2-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:51 +02:00

202 lines
5.3 KiB
C

/*
* Generic thunking code to convert data between host and target CPU
*
* Copyright (c) 2003 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef THUNK_H
#define THUNK_H
#include "cpu.h"
#include "exec/user/abitypes.h"
/* types enums definitions */
typedef enum argtype {
TYPE_NULL,
TYPE_CHAR,
TYPE_SHORT,
TYPE_INT,
TYPE_LONG,
TYPE_ULONG,
TYPE_PTRVOID, /* pointer on unknown data */
TYPE_LONGLONG,
TYPE_ULONGLONG,
TYPE_PTR,
TYPE_ARRAY,
TYPE_STRUCT,
TYPE_OLDDEVT,
} argtype;
#define MK_PTR(type) TYPE_PTR, type
#define MK_ARRAY(type, size) TYPE_ARRAY, size, type
#define MK_STRUCT(id) TYPE_STRUCT, id
#define THUNK_TARGET 0
#define THUNK_HOST 1
typedef struct {
/* standard struct handling */
const argtype *field_types;
int nb_fields;
int *field_offsets[2];
/* special handling */
void (*convert[2])(void *dst, const void *src);
int size[2];
int align[2];
const char *name;
} StructEntry;
/* Translation table for bitmasks... */
typedef struct bitmask_transtbl {
unsigned int target_mask;
unsigned int target_bits;
unsigned int host_mask;
unsigned int host_bits;
} bitmask_transtbl;
void thunk_register_struct(int id, const char *name, const argtype *types);
void thunk_register_struct_direct(int id, const char *name,
const StructEntry *se1);
const argtype *thunk_convert(void *dst, const void *src,
const argtype *type_ptr, int to_host);
extern StructEntry *struct_entries;
int thunk_type_size_array(const argtype *type_ptr, int is_host);
int thunk_type_align_array(const argtype *type_ptr, int is_host);
static inline int thunk_type_size(const argtype *type_ptr, int is_host)
{
int type, size;
const StructEntry *se;
type = *type_ptr;
switch(type) {
case TYPE_CHAR:
return 1;
case TYPE_SHORT:
return 2;
case TYPE_INT:
return 4;
case TYPE_LONGLONG:
case TYPE_ULONGLONG:
return 8;
case TYPE_LONG:
case TYPE_ULONG:
case TYPE_PTRVOID:
case TYPE_PTR:
if (is_host) {
return sizeof(void *);
} else {
return TARGET_ABI_BITS / 8;
}
break;
case TYPE_OLDDEVT:
if (is_host) {
#if defined(HOST_X86_64)
return 8;
#elif defined(HOST_ALPHA) || defined(HOST_IA64) || defined(HOST_MIPS) || \
defined(HOST_PARISC) || defined(HOST_SPARC64)
return 4;
#elif defined(HOST_PPC)
return sizeof(void *);
#else
return 2;
#endif
} else {
#if defined(TARGET_X86_64)
return 8;
#elif defined(TARGET_ALPHA) || defined(TARGET_IA64) || defined(TARGET_MIPS) || \
defined(TARGET_PARISC) || defined(TARGET_SPARC64)
return 4;
#elif defined(TARGET_PPC)
return TARGET_ABI_BITS / 8;
#else
return 2;
#endif
}
break;
case TYPE_ARRAY:
size = type_ptr[1];
return size * thunk_type_size_array(type_ptr + 2, is_host);
case TYPE_STRUCT:
se = struct_entries + type_ptr[1];
return se->size[is_host];
default:
g_assert_not_reached();
}
}
static inline int thunk_type_align(const argtype *type_ptr, int is_host)
{
int type;
const StructEntry *se;
type = *type_ptr;
switch(type) {
case TYPE_CHAR:
return 1;
case TYPE_SHORT:
if (is_host) {
return __alignof__(short);
} else {
return ABI_SHORT_ALIGNMENT;
}
case TYPE_INT:
if (is_host) {
return __alignof__(int);
} else {
return ABI_INT_ALIGNMENT;
}
case TYPE_LONGLONG:
case TYPE_ULONGLONG:
if (is_host) {
return __alignof__(long long);
} else {
return ABI_LLONG_ALIGNMENT;
}
case TYPE_LONG:
case TYPE_ULONG:
case TYPE_PTRVOID:
case TYPE_PTR:
if (is_host) {
return __alignof__(long);
} else {
return ABI_LONG_ALIGNMENT;
}
break;
case TYPE_OLDDEVT:
return thunk_type_size(type_ptr, is_host);
case TYPE_ARRAY:
return thunk_type_align_array(type_ptr + 2, is_host);
case TYPE_STRUCT:
se = struct_entries + type_ptr[1];
return se->align[is_host];
default:
g_assert_not_reached();
}
}
unsigned int target_to_host_bitmask(unsigned int target_mask,
const bitmask_transtbl * trans_tbl);
unsigned int host_to_target_bitmask(unsigned int host_mask,
const bitmask_transtbl * trans_tbl);
void thunk_init(unsigned int max_structs);
#endif