xemu/include/hw/loader.h
Michael S. Tsirkin 04920fc0fa loader: store FW CFG ROM files in RAM
ROM files that are put in FW CFG are copied to guest ram, by BIOS, but
they are not backed by RAM so they don't get migrated.

Each time we change two bytes in such a ROM this breaks cross-version
migration: since we can migrate after BIOS has read the first byte but
before it has read the second one, getting an inconsistent state.

Future-proof this by creating, for each such ROM,
an MR serving as the backing store.
This MR is never mapped into guest memory, but it's registered
as RAM so it's migrated with the guest.

Naturally, this only helps for -M 1.7 and up, older machine types
will still have the cross-version migration bug.
Luckily the race window for the problem to trigger is very small,
which is also likely why we didn't notice the cross-version
migration bug in testing yet.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2013-08-21 00:18:39 +03:00

68 lines
2.4 KiB
C

#ifndef LOADER_H
#define LOADER_H
#include "qapi/qmp/qdict.h"
#include "hw/nvram/fw_cfg.h"
/* loader.c */
int get_image_size(const char *filename);
int load_image(const char *filename, uint8_t *addr); /* deprecated */
int load_image_targphys(const char *filename, hwaddr,
uint64_t max_sz);
int load_elf(const char *filename, uint64_t (*translate_fn)(void *, uint64_t),
void *translate_opaque, uint64_t *pentry, uint64_t *lowaddr,
uint64_t *highaddr, int big_endian, int elf_machine,
int clear_lsb);
int load_aout(const char *filename, hwaddr addr, int max_sz,
int bswap_needed, hwaddr target_page_size);
int load_uimage(const char *filename, hwaddr *ep,
hwaddr *loadaddr, int *is_linux);
/**
* load_ramdisk:
* @filename: Path to the ramdisk image
* @addr: Memory address to load the ramdisk to
* @max_sz: Maximum allowed ramdisk size (for non-u-boot ramdisks)
*
* Load a ramdisk image with U-Boot header to the specified memory
* address.
*
* Returns the size of the loaded image on success, -1 otherwise.
*/
int load_ramdisk(const char *filename, hwaddr addr, uint64_t max_sz);
ssize_t read_targphys(const char *name,
int fd, hwaddr dst_addr, size_t nbytes);
void pstrcpy_targphys(const char *name,
hwaddr dest, int buf_size,
const char *source);
extern bool rom_file_in_ram;
int rom_add_file(const char *file, const char *fw_dir,
hwaddr addr, int32_t bootindex);
int rom_add_blob(const char *name, const void *blob, size_t len,
hwaddr addr);
int rom_add_elf_program(const char *name, void *data, size_t datasize,
size_t romsize, hwaddr addr);
int rom_load_all(void);
void rom_set_fw(FWCfgState *f);
int rom_copy(uint8_t *dest, hwaddr addr, size_t size);
void *rom_ptr(hwaddr addr);
void do_info_roms(Monitor *mon, const QDict *qdict);
#define rom_add_file_fixed(_f, _a, _i) \
rom_add_file(_f, NULL, _a, _i)
#define rom_add_blob_fixed(_f, _b, _l, _a) \
rom_add_blob(_f, _b, _l, _a)
#define PC_ROM_MIN_VGA 0xc0000
#define PC_ROM_MIN_OPTION 0xc8000
#define PC_ROM_MAX 0xe0000
#define PC_ROM_ALIGN 0x800
#define PC_ROM_SIZE (PC_ROM_MAX - PC_ROM_MIN_VGA)
int rom_add_vga(const char *file);
int rom_add_option(const char *file, int32_t bootindex);
#endif