614dd0585f
We have two places where we create identity mappings - one when we bring secondary CPUs online, and one where we setup some mappings for soft- reboot. Combine these two into a single implementation. Also collect the identity mapping deletion function. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
52 lines
1.3 KiB
C
52 lines
1.3 KiB
C
#include <linux/kernel.h>
|
|
|
|
#include <asm/cputype.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
|
|
{
|
|
unsigned long prot;
|
|
|
|
prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE;
|
|
if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
|
|
prot |= PMD_BIT4;
|
|
|
|
for (addr &= PGDIR_MASK; addr < end;) {
|
|
pmd_t *pmd = pmd_offset(pgd + pgd_index(addr), addr);
|
|
pmd[0] = __pmd(addr | prot);
|
|
addr += SECTION_SIZE;
|
|
pmd[1] = __pmd(addr | prot);
|
|
addr += SECTION_SIZE;
|
|
flush_pmd_entry(pmd);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_SMP
|
|
void identity_mapping_del(pgd_t *pgd, unsigned long addr, unsigned long end)
|
|
{
|
|
for (addr &= PGDIR_MASK; addr < end; addr += PGDIR_SIZE) {
|
|
pmd_t *pmd = pmd_offset(pgd + pgd_index(addr), addr);
|
|
pmd[0] = __pmd(0);
|
|
pmd[1] = __pmd(0);
|
|
clean_pmd_entry(pmd);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* In order to soft-boot, we need to insert a 1:1 mapping in place of
|
|
* the user-mode pages. This will then ensure that we have predictable
|
|
* results when turning the mmu off
|
|
*/
|
|
void setup_mm_for_reboot(char mode)
|
|
{
|
|
/*
|
|
* We need to access to user-mode page tables here. For kernel threads
|
|
* we don't have any user-mode mappings so we use the context that we
|
|
* "borrowed".
|
|
*/
|
|
identity_mapping_add(current->active_mm->pgd, 0, TASK_SIZE);
|
|
local_flush_tlb_all();
|
|
}
|