void __init efi_call_phys_epilog(void)
{
struct desc_ptr gdt_descr;
#ifdef CONFIG_PAX_KERNEXEC
struct desc_struct d;
memset(&d, 0, sizeof d);
write_gdt_entry(get_cpu_gdt_table(0), GDT_ENTRY_KERNEXEC_EFI_CS, &d, DESCTYPE_S);
write_gdt_entry(get_cpu_gdt_table(0), GDT_ENTRY_KERNEXEC_EFI_DS, &d, DESCTYPE_S);
#endif
gdt_descr.address = (unsigned long)get_cpu_gdt_table(0);
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
#ifdef CONFIG_PAX_PER_CPU_PGD
load_cr3(get_cpu_pgd(smp_processor_id(), kernel));
#else
load_cr3(swapper_pg_dir);
#endif
__flush_tlb_all();
local_irq_restore(efi_rt_eflags);
}
void init_kernel()
{
terminal_initialize();
init_serial(COM1);
terminal_enable_serial_echo(COM1);
terminal_printf("fOS version %s\n\n\n", KERNEL_VERSION);
kinit(end + 4096, end + 4096 + (100 * 4096));
init_gdt();
load_gdt();
load_idt();
load_isrs();
irq_install();
asm volatile ( "sti" );
timer_install();
sleep(1);
keyboard_install();
init_paging();
switch_to_paging();
}
void efi_call_phys_epilog(void)
{
unsigned long cr4;
struct desc_ptr gdt_descr;
gdt_descr.address = (unsigned long)get_cpu_gdt_table(0);
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
cr4 = read_cr4();
if (cr4 & X86_CR4_PAE) {
swapper_pg_dir[pgd_index(0)].pgd =
efi_bak_pg_dir_pointer[0].pgd;
} else {
swapper_pg_dir[pgd_index(0)].pgd =
efi_bak_pg_dir_pointer[0].pgd;
swapper_pg_dir[pgd_index(0x400000)].pgd =
efi_bak_pg_dir_pointer[1].pgd;
}
/*
* After the lock is released, the original page table is restored.
*/
__flush_tlb_all();
local_irq_restore(efi_rt_eflags);
}
/*
* ReBuild the initial GDT separating the kernel from the user memory
* area.
*
* See the memory layout in the linker script.
*
* Kernel code starts at 0x100000 (1MB), and is 1 MB long
* Kernel data starts at 0x200000 (2MB), and is 1 MB long
* Kernel stack starts at 0x400000 (4MB), and is 1 MB long
* (Stack grows downwards from 0x400000 to 0x300000)
*
* But there are other memory areas, esp. low ones (e.g. Video
* memory), that we need to access. So the kernel data _segment_ has
* to start from lowest memory. :-).
*
* User area starts from 0x401000 (4MB start offset of stack, and 1
* page size length), and is to the end of the memory. Define two
* segments that overlap. We need to control specific
* allocation. :-).
*
* For the moment, merging stack and data segments ...
* => kernel code seg starts at 0, and ends at 2 MB!
* => kernel data+stack seg starts at 2MB and is 2 MB long
*/
int
initialise_gdt_with_disjoint_kernel_and_user_memory (void)
{
int retval = FALSE;
int i = 0;
for (i = 0; i < 8192; i++)
global_descriptor_table[i].descriptor = 0;
i = set_total_gdt_entries (0);
retval = make_descriptor(0,
0,
NULL_DESCRIPTOR_FLAGS,
0
);
i = inc_total_gdt_entries ();
/* RING_0, DESC_CODEDATA, SEG_EXECUTE_READ, */
retval = make_descriptor ((MEMORYORIGIN),
((KERNELCODESTART + KERNELCODELENGTH)),
RING_0_CODEDATA_DESC_READ_EXECUTE,
1
);
i = inc_total_gdt_entries ();
/* RING_0, DESC_CODEDATA, SEG_READ_WRITE, */
retval = make_descriptor ((MEMORYORIGIN),
(TOTALKERNEL),
RING_0_CODEDATA_DESC_READ_WRITE,
2
);
i = inc_total_gdt_entries ();
/* RING_3, DESC_CODEDATA, SEG_EXECUTE_READ, */
retval = make_descriptor ((USERMEMORYSTART),
MAXMEMPAGES,
RING_3_CODEDATA_DESC_READ_EXECUTE,
3
);
i = inc_total_gdt_entries ();
/* RING_3, DESC_CODEDATA, SEG_READ_WRITE, */
retval = make_descriptor ((USERMEMORYSTART),
MAXMEMPAGES,
RING_3_CODEDATA_DESC_READ_WRITE,
4
);
i = get_total_gdt_entries ();
load_gdt (); /* Could some status flags tell us if we did ok? */
return retval;
}
void gdt_init(void)
{
struct gdt_ptr gdt_ptr;
gdt_ptr.base = (unsigned long) GDT;
gdt_ptr.limit = sizeof(GDT);
load_gdt(&gdt_ptr);
}
static void set_gdt(void *newgdt, __u16 limit)
{
struct desc_ptr curgdt;
/* ia32 supports unaligned loads & stores */
curgdt.size = limit;
curgdt.address = (unsigned long)newgdt;
load_gdt(&curgdt);
}
void __init efi_call_phys_epilog(pgd_t *save_pgd)
{
struct desc_ptr gdt_descr;
gdt_descr.address = (unsigned long)get_cpu_gdt_table(0);
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
load_cr3(save_pgd);
__flush_tlb_all();
}
/*
* Current gdt points %fs at the "master" per-cpu area: after this,
* it's on the real one.
*/
void switch_to_new_gdt(int cpu)
{
struct desc_ptr gdt_descr;
gdt_descr.address = (long)get_cpu_gdt_table(cpu);
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
/* Reload the per-cpu base */
load_percpu_segment(cpu);
}
void initialize_gdt()
{
struct desc_ptr desc_ptr;
gdt_entries[GDT_ENTRY_KERNEL_CS] = FULL_EXEC_SEGMENT;
gdt_entries[GDT_ENTRY_KERNEL_DS] = FULL_SEGMENT;
desc_ptr.size = sizeof(gdt_entries);
desc_ptr.address = (long)(&gdt_entries);
load_gdt(&desc_ptr);
}
void set_gdtr(void)
{
set_gdt(&gdt[0], 0, 0, 0, 0, 0, 0, 0, 0, 0);
set_gdt(&gdt[1], 0, 0x0FFFFF, 1, 0, 1, 10, 1, 1, 1);
set_gdt(&gdt[2], 0, 0x0FFFFF, 1, 0, 1, 2, 1, 1, 1);
gdtr.size = NUM_GDT * sizeof( SEGMENT_DESCRIPTOR );
gdtr.base = ( SEGMENT_DESCRIPTOR *)gdt;
load_gdt();
flush_pipeline();
}
pgd_t * __init efi_call_phys_prolog(void)
{
struct desc_ptr gdt_descr;
pgd_t *save_pgd;
/* Current pgd is swapper_pg_dir, we'll restore it later: */
save_pgd = swapper_pg_dir;
load_cr3(initial_page_table);
__flush_tlb_all();
gdt_descr.address = __pa(get_cpu_gdt_table(0));
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
return save_pgd;
}
void __init efi_call_phys_epilog(void)
{
struct desc_ptr gdt_descr;
gdt_descr.address = get_cpu_gdt_table(0);
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
clone_pgd_range(swapper_pg_dir, efi_bak_pg_dir_pointer, KERNEL_PGD_PTRS);
/*
* After the lock is released, the original page table is restored.
*/
__flush_tlb_all();
local_irq_restore(efi_rt_eflags);
}
static void __restore_processor_state(struct saved_context *ctxt)
{
/*
* control registers
*/
/* cr4 was introduced in the Pentium CPU */
if (ctxt->cr4)
write_cr4(ctxt->cr4);
write_cr3(ctxt->cr3);
write_cr2(ctxt->cr2);
write_cr0(ctxt->cr0);
/*
* now restore the descriptor tables to their proper values
* ltr is done i fix_processor_context().
*/
load_gdt(&ctxt->gdt);
load_idt(&ctxt->idt);
/*
* segment registers
*/
loadsegment(es, ctxt->es);
loadsegment(fs, ctxt->fs);
loadsegment(gs, ctxt->gs);
loadsegment(ss, ctxt->ss);
/*
* sysenter MSRs
*/
if (boot_cpu_has(X86_FEATURE_SEP))
enable_sep_cpu();
/*
* restore XCR0 for xsave capable cpu's.
*/
if (cpu_has_xsave)
xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
fix_processor_context();
do_fpu_end();
mtrr_ap_init();
mcheck_init(&boot_cpu_data);
}
void __init efi_call_phys_prelog(void)
{
struct desc_ptr gdt_descr;
local_irq_save(efi_rt_eflags);
clone_pgd_range(efi_bak_pg_dir_pointer, swapper_pg_dir, KERNEL_PGD_PTRS);
clone_pgd_range(swapper_pg_dir, swapper_pg_dir + KERNEL_PGD_BOUNDARY,
min_t(unsigned long, KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
/*
* After the lock is released, the original page table is restored.
*/
__flush_tlb_all();
gdt_descr.address = (struct desc_struct *)__pa(get_cpu_gdt_table(0));
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
}
void efi_call_phys_prelog(void)
{
unsigned long cr4;
unsigned long temp;
struct desc_ptr gdt_descr;
local_irq_save(efi_rt_eflags);
/*
* If I don't have PAE, I should just duplicate two entries in page
* directory. If I have PAE, I just need to duplicate one entry in
* page directory.
*/
cr4 = read_cr4();
if (cr4 & X86_CR4_PAE) {
efi_bak_pg_dir_pointer[0].pgd =
swapper_pg_dir[pgd_index(0)].pgd;
swapper_pg_dir[0].pgd =
swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
} else {
efi_bak_pg_dir_pointer[0].pgd =
swapper_pg_dir[pgd_index(0)].pgd;
efi_bak_pg_dir_pointer[1].pgd =
swapper_pg_dir[pgd_index(0x400000)].pgd;
swapper_pg_dir[pgd_index(0)].pgd =
swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
temp = PAGE_OFFSET + 0x400000;
swapper_pg_dir[pgd_index(0x400000)].pgd =
swapper_pg_dir[pgd_index(temp)].pgd;
}
/*
* After the lock is released, the original page table is restored.
*/
__flush_tlb_all();
gdt_descr.address = __pa(get_cpu_gdt_table(0));
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
}
// Name: initialize_gdt
// Description: This function will create the global descriptor table and then loads the GDTR
// Parameter: -
// Return: -
void initialize_gdt()
{
struct descriptor null_entry, cs_entry, ds_entry;
gdptr.base_address = (unsigned int)&global_desc_table;
gdptr.size =(unsigned short int) sizeof(struct descriptor_table_entry)*3 - 1;
null_entry = getDescriptor(0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
global_desc_table[0] = descriptortotableentry(null_entry);
cs_entry = getDescriptor(0, 0xFFFFFFFF, 10, 1, 0, 0, 1, 1, 0, 1 );
global_desc_table[1] = descriptortotableentry(cs_entry);
ds_entry = getDescriptor(0, 0xFFFFFFFF, 2, 1, 0, 0, 1, 1, 0, 1 );
global_desc_table[2] = descriptortotableentry(ds_entry);
//putc('x');
load_gdt();
return;
}
void __restore_processor_state(struct saved_context *ctxt)
{
/*
* control registers
*/
write_cr4(ctxt->cr4);
write_cr3(ctxt->cr3);
write_cr2(ctxt->cr2);
write_cr2(ctxt->cr0);
/*
* now restore the descriptor tables to their proper values
* ltr is done i fix_processor_context().
*/
load_gdt(&ctxt->gdt_limit);
load_idt(&ctxt->idt_limit);
/*
* segment registers
*/
loadsegment(es, ctxt->es);
loadsegment(fs, ctxt->fs);
loadsegment(gs, ctxt->gs);
loadsegment(ss, ctxt->ss);
#ifdef CONFIG_SYSENTER
/*
* sysenter MSRs
*/
if (boot_cpu_has(X86_FEATURE_SEP))
enable_sep_cpu();
#endif
fix_processor_context();
do_fpu_end();
mtrr_ap_init();
}
void __init efi_call_phys_prolog(void)
{
struct desc_ptr gdt_descr;
#ifdef CONFIG_PAX_KERNEXEC
struct desc_struct d;
#endif
local_irq_save(efi_rt_eflags);
load_cr3(initial_page_table);
__flush_tlb_all();
#ifdef CONFIG_PAX_KERNEXEC
pack_descriptor(&d, 0, 0xFFFFF, 0x9B, 0xC);
write_gdt_entry(get_cpu_gdt_table(0), GDT_ENTRY_KERNEXEC_EFI_CS, &d, DESCTYPE_S);
pack_descriptor(&d, 0, 0xFFFFF, 0x93, 0xC);
write_gdt_entry(get_cpu_gdt_table(0), GDT_ENTRY_KERNEXEC_EFI_DS, &d, DESCTYPE_S);
#endif
gdt_descr.address = __pa(get_cpu_gdt_table(0));
gdt_descr.size = GDT_SIZE - 1;
load_gdt(&gdt_descr);
}
static void __init init_gdt(void)
{
load_gdt(0);
}
