Пример #1
0
void __init setup_physmem(unsigned long start, unsigned long reserve_end,
			  unsigned long len, unsigned long long highmem)
{
	unsigned long reserve = reserve_end - start;
	int pfn = PFN_UP(__pa(reserve_end));
	int delta = (len - reserve) >> PAGE_SHIFT;
	int err, offset, bootmap_size;

	physmem_fd = create_mem_file(len + highmem);

	offset = uml_reserved - uml_physmem;
	err = os_map_memory((void *) uml_reserved, physmem_fd, offset,
			    len - offset, 1, 1, 1);
	if (err < 0) {
		printf("setup_physmem - mapping %ld bytes of memory at 0x%p "
		       "failed - errno = %d\n", len - offset,
		       (void *) uml_reserved, err);
		exit(1);
	}

	/*
	 * Special kludge - This page will be mapped in to userspace processes
	 * from physmem_fd, so it needs to be written out there.
	 */
	os_seek_file(physmem_fd, __pa(&__syscall_stub_start));
	os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE);

	bootmap_size = init_bootmem(pfn, pfn + delta);
	free_bootmem(__pa(reserve_end) + bootmap_size,
		     len - bootmap_size - reserve);
}
Пример #2
0
int __init can_drop_memory(void)
{
	void *addr;
	int fd, ok = 0;

	printk("Checking host MADV_REMOVE support...");
	fd = create_mem_file(UM_KERN_PAGE_SIZE);
	if(fd < 0){
		printk("Creating test memory file failed, err = %d\n", -fd);
		goto out;
	}

	addr = mmap64(NULL, UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
		      MAP_SHARED, fd, 0);
	if(addr == MAP_FAILED){
		printk("Mapping test memory file failed, err = %d\n", -errno);
		goto out_close;
	}

	if(madvise(addr, UM_KERN_PAGE_SIZE, MADV_REMOVE) != 0){
		printk("MADV_REMOVE failed, err = %d\n", -errno);
		goto out_unmap;
	}

	printk("OK\n");
	ok = 1;

out_unmap:
	munmap(addr, UM_KERN_PAGE_SIZE);
out_close:
	close(fd);
out:
	return ok;
}
Пример #3
0
void remap_data(void *segment_start, void *segment_end, int w)
{
	void *addr;
	unsigned long size;
	int data, prot;

	if(w) prot = PROT_WRITE;
	else prot = 0;
	prot |= PROT_READ | PROT_EXEC;
	size = (unsigned long) segment_end - 
		(unsigned long) segment_start;
	data = create_mem_file(size);
	addr = mmap(NULL, size, PROT_WRITE | PROT_READ, MAP_SHARED, data, 0);
	if(addr == MAP_FAILED){
		perror("mapping new data segment");
		exit(1);
	}
	memcpy(addr, segment_start, size);
	if(switcheroo(data, prot, addr, segment_start, size) < 0){
		printf("switcheroo failed\n");
		exit(1);
	}
}
Пример #4
0
int
main (int argc, char* argv[]) 
{
	int fd, kernel_fd = -1;
	
	/* scanning whether there's -h or --help in the options */
	char c, *unit;
	while ((c = getopt_long(argc, argv, ":skmdx:", longopts, 0)) != -1) {
		switch (c) {
		case 'h':
			printf ("  -d <path>, --disk=<path>    specify normal disk\n"
					"  -k <path>, --kernel=<path>  specify kernel file\n"
					"  -m NUM   , --memsize=NUM    specify memory size\n"
					"  -s <path>, --swap=<path>    specify swap disk\n"
					"  -h, --help                  print this message and exit\n");
			return 0;
			break;
		case 'k':
			if ((kernel_fd = open (optarg, O_RDONLY)) < 0)
				return 1;
			break;
		case 'm':
			memsize = strtol (optarg, &unit, 10);
			if (*unit == 'K' || *unit == 'k')
				memsize <<= 10;
			else if (*unit == 'M' || *unit == 'm')
				memsize <<= 20;
			break;
		default:
			/* ignore other options now */
			break;
		}
	}
	if (kernel_fd < 0) {
		printf ("No kernel file specified.\n");
		return 1;
	}
	
	struct stat buf;
	fstat (kernel_fd, &buf);
	
	fd = create_mem_file (memsize);

	/* map the temp file & copy boot and kernel code to the memory */
	int brk_end = (int)sbrk (0);
	mmap ((void*)brk_end, memsize, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_SHARED, fd, 0);

	read_kernel (kernel_fd, brk_end - KERNBASE);

	/* map the reserved part to where it really should be */
	mmap ((void*)KERNBASE, RESERVED_SIZE, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_SHARED, fd, 0);

	/* Now we have access to ginfo normally. */
	ginfo->mem_fd = fd;
	e820_init (kernel_fd);
	parse_opts (argc, argv);

	/* unmap useless page table entries */
	memcpy ((void*)(BOOT_CODE), (void*)&__boot_start, PGSIZE);
	stk_init (brk_end, fd);
	
	void (*boot_start) (void);
	boot_start = __pa (__boot_entry);
	boot_start ();

	return 0;
}