On 28/06/2016 11:01, Peter Lieven wrote:
> a classic use for mmap here.
>
> Signed-off-by: Peter Lieven <[email protected]>
They are never freed, why does mmap help?
Paolo
> ---
> hw/core/loader.c | 16 +++++++---------
> 1 file changed, 7 insertions(+), 9 deletions(-)
>
> diff --git a/hw/core/loader.c b/hw/core/loader.c
> index 53e0e41..f217edc 100644
> --- a/hw/core/loader.c
> +++ b/hw/core/loader.c
> @@ -55,6 +55,7 @@
> #include "exec/address-spaces.h"
> #include "hw/boards.h"
> #include "qemu/cutils.h"
> +#include "qemu/mmap-alloc.h"
>
> #include <zlib.h>
>
> @@ -837,7 +838,7 @@ int rom_add_file(const char *file, const char *fw_dir,
> {
> MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine());
> Rom *rom;
> - int rc, fd = -1;
> + int fd = -1;
> char devpath[100];
>
> rom = g_malloc0(sizeof(*rom));
> @@ -867,12 +868,9 @@ int rom_add_file(const char *file, const char *fw_dir,
> }
>
> rom->datasize = rom->romsize;
> - rom->data = g_malloc0(rom->datasize);
> - lseek(fd, 0, SEEK_SET);
> - rc = read(fd, rom->data, rom->datasize);
> - if (rc != rom->datasize) {
> - fprintf(stderr, "rom: file %-20s: read error: rc=%d (expected
> %zd)\n",
> - rom->name, rc, rom->datasize);
> + rom->data = mmap(NULL, rom->datasize, PROT_READ, MAP_SHARED, fd, 0);
> + if (rom->data == MAP_FAILED) {
> + fprintf(stderr, "rom: file %-20s: mmap error\n", rom->name);
> goto err;
> }
> close(fd);
> @@ -915,7 +913,7 @@ err:
> if (fd != -1)
> close(fd);
>
> - g_free(rom->data);
> + qemu_anon_ram_munmap(rom->data, rom->romsize);
> g_free(rom->path);
> g_free(rom->name);
> if (fw_dir) {
> @@ -1013,7 +1011,7 @@ static void rom_reset(void *unused)
> }
> if (rom->isrom) {
> /* rom needs to be written only once */
> - g_free(rom->data);
> + qemu_anon_ram_munmap(rom->data, rom->datasize);
> rom->data = NULL;
> }
> /*
>
