/**
* Page table mapper init function.
* @note This function should be called by mmu init.
*/
int ptmapper_init(void)
{
SUBSYS_INIT("ptmapper");
#if defined(configPTMAPPER_DEBUG)
kputs("\n");
#endif
/* Allocate memory for mmu_pagetable_master */
if (ptmapper_alloc(&mmu_pagetable_master)) {
/* Critical failure */
panic("Can't allocate memory for master page table.\n");
}
mmu_pagetable_system.master_pt_addr = mmu_pagetable_master.master_pt_addr;
mmu_pagetable_system.nr_tables =
(MMU_VADDR_KERNEL_END + 1) / MMU_PGSIZE_SECTION;
if (ptmapper_alloc(&mmu_pagetable_system)) {
/* Critical failure */
panic("Can't allocate memory for system page table.\n");
}
/* Initialize system page tables */
mmu_init_pagetable(&mmu_pagetable_master);
mmu_init_pagetable(&mmu_pagetable_system);
/*
* Init regions
*/
/* Kernel ro region */
mmu_region_kernel.num_pages = MMU_PAGE_CNT_BY_RANGE(
MMU_VADDR_KERNEL_START, (intptr_t)(&_rodata_end) - 1,
MMU_PGSIZE_COARSE);
/* Kernel rw data region */
mmu_region_kdata.vaddr = (intptr_t)(&_data_start);
mmu_region_kdata.num_pages = MMU_PAGE_CNT_BY_RANGE(
(intptr_t)(&_data_start), MMU_VADDR_KERNEL_END,
MMU_PGSIZE_COARSE);
mmu_region_kdata.paddr = (intptr_t)(&_data_start);
/* Fill page tables with translations & attributes */
{
mmu_region_t ** regp;
#if defined(configPTMAPPER_DEBUG)
const char str_type[2][9] = {"sections", "pages"};
#define PRINTMAPREG(region) \
KERROR(KERROR_DEBUG, "Mapped %s: %u %s\n", \
#region, region.num_pages, \
(region.pt->pt_type == MMU_PTT_MASTER) ? \
str_type[0] : str_type[1]);
#else
#define PRINTMAPREG(region)
#endif
#define MAP_REGION(reg) \
mmu_map_region(®); \
PRINTMAPREG(reg)
MAP_REGION(mmu_region_kstack);
MAP_REGION(mmu_region_kernel);
MAP_REGION(mmu_region_kdata);
MAP_REGION(mmu_region_page_tables);
#undef MAP_REGION
#undef PRINTMAPREG
SET_FOREACH(regp, ptmapper_fixed_regions) {
mmu_map_region(*regp);
}
}
static pthread_t create_uinit_main(void * stack_addr)
{
struct _sched_pthread_create_args init_ds = {
.param.sched_policy = SCHED_OTHER,
.param.sched_priority = NZERO,
.stack_addr = stack_addr,
.stack_size = configUSRINIT_SSIZE,
.flags = 0,
.start = uinit, /* We have to first get into user space to use exec
* and mount the rootfs.
*/
.arg1 = (uintptr_t)rootfs,
.del_thread = (void (*)(void *))uinit_exit,
};
return thread_create(&init_ds, THREAD_MODE_PRIV);
}
/**
* Map vmstack to proc.
*/
static void map_vmstack2proc(struct proc_info * proc, struct buf * vmstack)
{
struct vm_pt * vpt;
(*proc->mm.regions)[MM_STACK_REGION] = vmstack;
vm_updateusr_ap(vmstack);
vpt = ptlist_get_pt(&proc->mm, vmstack->b_mmu.vaddr,
MMU_PGSIZE_COARSE, VM_PT_CREAT);
if (vpt == 0)
panic("Couldn't get vpt for init stack");
vmstack->b_mmu.pt = &(vpt->pt);
vm_map_region(vmstack, vpt);
}
/**
* Create init process.
*/
int __kinit__ kinit(void)
{
SUBSYS_DEP(sched_init);
SUBSYS_DEP(proc_init);
SUBSYS_DEP(ramfs_init);
SUBSYS_DEP(sysctl_init);
SUBSYS_INIT("kinit");
char strbuf[80]; /* Buffer for panic messages. */
struct buf * init_vmstack;
pthread_t tid;
pid_t pid;
struct thread_info * init_thread;
struct proc_info * init_proc;
/*
* FIXME Memory allocation, protection or manipulation bug!
* There is a critical bug causing random crashes in userland. I suspect
* something is overwriting user space allocation from the kernel space.
* Allocating some memory before init is executed seems to fix this issue,
* however naturally this is not the proper way to fix the bug.
* Without the allocation here the issue is sometimes seen in init or
* usually after couple of fork + exec + exit cycles. The usual symptom is
* that the userland app first calls some 0:0 syscalls and then tries to
* execute undefined instruction, which probably means that either some
* jump table in the heap or some part of the executable code is modified
* by a bad access in kernel mode just before this happens.
*/
(void)geteblk(MMU_PGSIZE_COARSE * 10);
mount_tmp_rootfs();
/*
* User stack for init
*/
init_vmstack = create_vmstack();
if (!init_vmstack)
panic("Can't allocate a stack for init");
/*
* Create a thread for init
*/
tid = create_uinit_main((void *)(init_vmstack->b_mmu.paddr));
if (tid < 0) {
ksprintf(strbuf, sizeof(strbuf), "Can't create a thread for init. %i",
tid);
panic(strbuf);
}
/*
* pid of init
*/
pid = proc_fork();
if (pid <= 0) {
ksprintf(strbuf, sizeof(strbuf), "Can't fork a process for init. %i",
pid);
panic(strbuf);
}
init_thread = thread_lookup(tid);
if (!init_thread) {
panic("Can't get thread descriptor of init_thread!");
}
init_proc = proc_ref(pid);
if (!init_proc || (init_proc->state == PROC_STATE_INITIAL)) {
panic("Failed to get proc struct or invalid struct");
}
init_thread->pid_owner = pid;
init_thread->curr_mpt = &init_proc->mm.mpt;
/*
* Map the previously created user stack with init process page table.
*/
map_vmstack2proc(init_proc, init_vmstack);
/*
* Map tkstack of init with vm_pagetable_system.
*/
mmu_map_region(&init_thread->kstack_region->b_mmu);
init_proc->main_thread = init_thread;
KERROR_DBG("Init created with pid: %u, tid: %u, stack: %p\n",
pid, tid, (void *)init_vmstack->b_mmu.vaddr);
proc_unref(init_proc);
return 0;
}
void bcm2835_mmio_init(void)
{
mmu_map_region(&bcm2835_mmio_region);
}