/**
* detector_init - Standard module initialization code
*/
static int detector_init(void)
{
int ret = -ENOMEM;
printk(KERN_INFO BANNER "version %s\n", VERSION);
ret = init_stats();
if (0 != ret)
goto out;
ret = init_debugfs();
if (0 != ret)
goto err_stats;
if (enabled)
ret = start_kthread();
goto out;
err_stats:
ring_buffer_free(ring_buffer);
out:
return ret;
}
void kmain(struct multiboot_info *mbt)
{
vga_init();
gdt_install();
idt_install();
isr_install();
irq_install();
syscalls_install();
puts_c(__kernel_name " kernel v" __kernel_version_str "\n\n", COLOR_LIGHT_BLUE, COLOR_DEFAULT_BG);
uint64_t mem;
get_multiboot_info(mbt, &mem);
extern uint32_t _kernel_memory_end[];
kprintf("End of kernel's memory: 0x%x\n", (uint64_t) (uint32_t) _kernel_memory_end);
kprintf("Memory:\n%l B\n%l KB\n%l MB\n%l GB\n", mem, mem / 1024, mem / 1024 / 1024, mem / 1024 / 1024 / 1024);
init_paging();
map_page(0xFD7FF000, 0x60000, 3);
int *p = (int *) 0xFD7FF000;
*p = 12;
kprintf("*(0x%x) = %i\n", (uint64_t) (uint32_t) p, *p);
map_page(0x10000000, 0x60000, 3);
int *p2 = (int *) 0x10000000;
kprintf("*(0x%x) = %i\n", (uint64_t) (uint32_t) p2, *p2);
print_next_available_page();
uint32_t ap = allocate_page(203);
map_page(ap, 0x60000, 3);
int *p3 = (int *) ap;
kprintf("*(0x%x) = %i\n", (uint64_t) ap, *p3);
print_next_available_page();
ap = allocate_page(203);
kprintf("ap = 0x%x\n", (uint32_t) ap);
struct kthread thread;
create_kthread(thread_test, &thread);
start_kthread(&thread);
kprintf("Returned from thread.\n");
_asm_print_test();
return;
}
/**
* debug_enable_fwrite - Write function for "enable" debugfs interface
* @filp: The active open file structure for the debugfs "file"
* @ubuf: The user buffer that contains the value to write
* @cnt: The maximum number of bytes to write to "file"
* @ppos: The current position in the debugfs "file"
*
* This function provides a write implementation for the "enable" debugfs
* interface to the hardware latency detector. Can be used to enable or
* disable the detector, which will have the side-effect of possibly
* also resetting the global stats and kicking off the measuring
* kthread (on an enable) or the converse (upon a disable).
*/
static ssize_t debug_enable_fwrite(struct file *filp,
const char __user *ubuf,
size_t cnt,
loff_t *ppos)
{
char buf[4];
int csize = min(cnt, sizeof(buf));
long val = 0;
int err = 0;
memset(buf, '\0', sizeof(buf));
if (copy_from_user(buf, ubuf, csize))
return -EFAULT;
buf[sizeof(buf)-1] = '\0'; /* just in case */
err = strict_strtoul(buf, 10, &val);
if (0 != err)
return -EINVAL;
if (val) {
if (enabled)
goto unlock;
enabled = 1;
__reset_stats();
if (start_kthread())
return -EFAULT;
} else {
if (!enabled)
goto unlock;
enabled = 0;
err = stop_kthread();
if (err) {
printk(KERN_ERR BANNER "cannot stop kthread\n");
return -EFAULT;
}
wake_up(&data.wq); /* reader(s) should return */
}
unlock:
return csize;
}