void HMA_MAP(int HMA)
{
int ret;
/* destroy simx86 memory protections first */
e_invalidate_full(HMAAREA, HMASIZE);
/* Note: MAPPING_HMA is magic, dont be confused by src==dst==HMAAREA here */
off_t src = HMA ? HMAAREA : 0;
x_printf("Entering HMA_MAP with HMA=%d\n", HMA);
ret = alias_mapping(MAPPING_HMA, HMAAREA, HMASIZE,
PROT_READ | PROT_WRITE | PROT_EXEC, LOWMEM(src));
if (ret == -1) {
x_printf("HMA: Mapping HMA to HMAAREA %#x unsuccessful: %s\n",
HMAAREA, strerror(errno));
leavedos(47);
}
x_printf("HMA: mapped\n");
}
/*
* DANG_BEGIN_FUNCTION low_mem_init
*
* description:
* Initializes the lower 1Meg via mmap & sets up the HMA region
*
* DANG_END_FUNCTION
*/
void low_mem_init(void)
{
void *lowmem, *result;
#ifdef __i386__
PRIV_SAVE_AREA
#endif
open_mapping(MAPPING_INIT_LOWRAM);
g_printf ("DOS+HMA memory area being mapped in\n");
lowmem = alloc_mapping(MAPPING_INIT_LOWRAM, LOWMEM_SIZE + HMASIZE, -1);
if (lowmem == MAP_FAILED) {
perror("LOWRAM alloc");
leavedos(98);
}
#ifdef __i386__
/* we may need root to mmap address 0 */
enter_priv_on();
result = alias_mapping(MAPPING_INIT_LOWRAM, 0, LOWMEM_SIZE + HMASIZE,
PROT_READ | PROT_WRITE | PROT_EXEC, lowmem);
leave_priv_setting();
if (result == MAP_FAILED && (errno == EPERM || errno == EACCES)) {
#ifndef X86_EMULATOR
perror ("LOWRAM mmap");
fprintf(stderr, "Cannot map low DOS memory (the first 640k).\n"
"You can most likely avoid this problem by running\n"
"sysctl -w vm.mmap_min_addr=0\n"
"as root, or by changing the vm.mmap_min_addr setting in\n"
"/etc/sysctl.conf or a file in /etc/sysctl.d/ to 0.\n"
"If this doesn't help, disable selinux in /etc/selinux/config\n"
);
exit(EXIT_FAILURE);
#else
if (config.cpuemu < 3)
{
/* switch on vm86-only JIT CPU emulation to with non-zero base */
config.cpuemu = 3;
init_emu_cpu();
c_printf("CONF: JIT CPUEMU set to 3 for %d86\n", (int)vm86s.cpu_type);
error("Using CPU emulation because vm.mmap_min_addr > 0.\n"
"You can most likely avoid this problem by running\n"
"sysctl -w vm.mmap_min_addr=0\n"
"as root, or by changing the vm.mmap_min_addr setting in\n"
"/etc/sysctl.conf or a file in /etc/sysctl.d/ to 0.\n"
"If this doesn't help, disable selinux in /etc/selinux/config\n"
);
}
result = alias_mapping(MAPPING_INIT_LOWRAM, -1, LOWMEM_SIZE + HMASIZE,
PROT_READ | PROT_WRITE | PROT_EXEC, lowmem);
#endif
}
#else
result = alias_mapping(MAPPING_INIT_LOWRAM, -1, LOWMEM_SIZE + HMASIZE,
PROT_READ | PROT_WRITE | PROT_EXEC, lowmem);
if (config.cpuemu < 3) {
/* switch on vm86-only JIT CPU emulation to with non-zero base */
config.cpuemu = 3;
init_emu_cpu();
c_printf("CONF: JIT CPUEMU set to 3 for %d86\n", (int)vm86s.cpu_type);
}
#endif
if (result == MAP_FAILED) {
perror ("LOWRAM mmap");
exit(EXIT_FAILURE);
}
#ifdef X86_EMULATOR
if (result) {
warn("WARN: using non-zero memory base address %p.\n"
"WARN: You can use the better-tested zero based setup using\n"
"WARN: sysctl -w vm.mmap_min_addr=0\n"
"WARN: as root, or by changing the vm.mmap_min_addr setting in\n"
"WARN: /etc/sysctl.conf or a file in /etc/sysctl.d/ to 0.\n",
result);
}
#endif
/* keep conventional memory protected as long as possible to protect
NULL pointer dereferences */
mprotect_mapping(MAPPING_LOWMEM, result, config.mem_size * 1024, PROT_NONE);
}
