diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index f409fe2..d1d30db 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -18,6 +18,10 @@ #include #include #include +#include + +/* Physical address */ +#define pa(X) ((X) - __PAGE_OFFSET) /* * References to members of the new_cpu_data structure. @@ -79,10 +83,6 @@ INIT_MAP_BEYOND_END = BOOTBITMAP_SIZE + (PAGE_TABLE_SIZE + ALLOCATOR_SLOP)*PAGE_ */ .section .text.head,"ax",@progbits ENTRY(startup_32) - /* check to see if KEEP_SEGMENTS flag is meaningful */ - cmpw $0x207, BP_version(%esi) - jb 1f - /* test KEEP_SEGMENTS flag to see if the bootloader is asking us to not reload segments */ testb $(1<<6), BP_loadflags(%esi) @@ -91,7 +91,7 @@ ENTRY(startup_32) /* * Set segments to known values. */ -1: lgdt boot_gdt_descr - __PAGE_OFFSET +1: lgdt pa(boot_gdt_descr) movl $(__BOOT_DS),%eax movl %eax,%ds movl %eax,%es @@ -104,8 +104,8 @@ ENTRY(startup_32) */ cld xorl %eax,%eax - movl $__bss_start - __PAGE_OFFSET,%edi - movl $__bss_stop - __PAGE_OFFSET,%ecx + movl $pa(__bss_start),%edi + movl $pa(__bss_stop),%ecx subl %edi,%ecx shrl $2,%ecx rep ; stosl @@ -117,31 +117,32 @@ ENTRY(startup_32) * (kexec on panic case). Hence copy out the parameters before initializing * page tables. */ - movl $(boot_params - __PAGE_OFFSET),%edi + movl $pa(boot_params),%edi movl $(PARAM_SIZE/4),%ecx cld rep movsl - movl boot_params - __PAGE_OFFSET + NEW_CL_POINTER,%esi + movl pa(boot_params) + NEW_CL_POINTER,%esi andl %esi,%esi jz 1f # No comand line - movl $(boot_command_line - __PAGE_OFFSET),%edi + movl $pa(boot_command_line),%edi movl $(COMMAND_LINE_SIZE/4),%ecx rep movsl 1: #ifdef CONFIG_PARAVIRT - cmpw $0x207, (boot_params + BP_version - __PAGE_OFFSET) + /* This is can only trip for a broken bootloader... */ + cmpw $0x207, pa(boot_params + BP_version) jb default_entry /* Paravirt-compatible boot parameters. Look to see what architecture we're booting under. */ - movl (boot_params + BP_hardware_subarch - __PAGE_OFFSET), %eax + movl pa(boot_params + BP_hardware_subarch), %eax cmpl $num_subarch_entries, %eax jae bad_subarch - movl subarch_entries - __PAGE_OFFSET(,%eax,4), %eax + movl pa(subarch_entries)(,%eax,4), %eax subl $__PAGE_OFFSET, %eax jmp *%eax @@ -167,17 +168,74 @@ num_subarch_entries = (. - subarch_entries) / 4 * Mappings are created both at virtual address 0 (identity mapping) * and PAGE_OFFSET for up to _end+sizeof(page tables)+INIT_MAP_BEYOND_END. * - * Warning: don't use %esi or the stack in this code. However, %esp - * can be used as a GPR if you really need it... + * Note that the stack is not yet set up! */ -page_pde_offset = (__PAGE_OFFSET >> 20); +#define PTE_ATTR 0x007 /* PRESENT+RW+USER */ +#define PDE_ATTR 0x067 /* PRESENT+RW+USER+DIRTY+ACCESSED */ +#define PGD_ATTR 0x001 /* PRESENT (no other attributes) */ default_entry: - movl $(pg0 - __PAGE_OFFSET), %edi - movl $(swapper_pg_dir - __PAGE_OFFSET), %edx - movl $0x007, %eax /* 0x007 = PRESENT+RW+USER */ +#ifdef CONFIG_X86_PAE + /* + * In PAE mode, the kernel PMD is shared, and __PAGE_OFFSET + * is guaranteed to be a multiple of 1 GB (the PGD granulatity.) + * Thus, we only need to set up a single PMD here; the identity + * mapping is handled by pointing two PGD entries to the PMD. + * + * Note the upper half of each PMD or PTE are always zero at + * this stage. + */ +page_pde_offset = (__PAGE_OFFSET >> 27); + + movl %cr4, %eax + orl $X86_CR4_PAE, %eax + movl %eax, %cr4 + + xorl %ebx,%ebx /* %ebx is kept at zero */ + + movl $pa(pg0), %edi + movl $pa(swapper_pg_pmd), %edx + movl $PTE_ATTR, %eax +10: + leal PDE_ATTR(%edi),%ecx /* Create PMD entry */ + movl %ecx,(%edx) /* Store PMD entry */ + /* Upper half already zero */ + addl $8,%edx + movl $512,%ecx +11: + stosl + xchgl %eax,%ebx + stosl + xchgl %eax,%ebx + addl $0x1000,%eax + loop 11b + + /* + * End condition: we must map up to and including INIT_MAP_BEYOND_END + * bytes beyond the end of our own page tables. + */ + leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp + cmpl %ebp,%eax + jb 10b + movl %edi,pa(init_pg_tables_end) + + /* Set up the PGD */ + movl $pa(swapper_pg_pmd)+PGD_ATTR, %eax + movl %eax, pa(swapper_pg_dir) /* Identity map */ + movl %eax, pa(swapper_pg_dir+page_pde_offset) /* Kernel map */ + + /* Do early initialization of the fixmap area */ + movl $pa(swapper_pg_fixmap)+PDE_ATTR,%eax + movl %eax,pa(swapper_pg_pmd+0xff8) +#else /* Not PAE */ + +page_pde_offset = (__PAGE_OFFSET >> 20); + + movl $pa(pg0), %edi + movl $pa(swapper_pg_dir), %edx + movl $PTE_ATTR, %eax 10: - leal 0x007(%edi),%ecx /* Create PDE entry */ + leal PDE_ATTR(%edi),%ecx /* Create PDE entry */ movl %ecx,(%edx) /* Store identity PDE entry */ movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */ addl $4,%edx @@ -186,19 +244,20 @@ default_entry: stosl addl $0x1000,%eax loop 11b - /* End condition: we must map up to and including INIT_MAP_BEYOND_END */ - /* bytes beyond the end of our own page tables; the +0x007 is the attribute bits */ - leal (INIT_MAP_BEYOND_END+0x007)(%edi),%ebp + /* + * End condition: we must map up to and including INIT_MAP_BEYOND_END + * bytes beyond the end of our own page tables; the +0x007 is + * the attribute bits + */ + leal (INIT_MAP_BEYOND_END+PTE_ATTR)(%edi),%ebp cmpl %ebp,%eax jb 10b - movl %edi,(init_pg_tables_end - __PAGE_OFFSET) - - /* Do an early initialization of the fixmap area */ - movl $(swapper_pg_dir - __PAGE_OFFSET), %edx - movl $(swapper_pg_pmd - __PAGE_OFFSET), %eax - addl $0x67, %eax /* 0x67 == _PAGE_TABLE */ - movl %eax, 4092(%edx) + movl %edi,pa(init_pg_tables_end) + /* Do early initialization of the fixmap area */ + movl $pa(swapper_pg_fixmap)+PDE_ADDR,%eax + movl %eax,pa(swapper_pg_dir+0xffc) +#endif xorl %ebx,%ebx /* This is the boot CPU (BSP) */ jmp 3f /* @@ -237,7 +296,7 @@ ENTRY(startup_32_smp) * NOTE! We have to correct for the fact that we're * not yet offset PAGE_OFFSET.. */ -#define cr4_bits mmu_cr4_features-__PAGE_OFFSET +#define cr4_bits pa(mmu_cr4_features) movl cr4_bits,%edx andl %edx,%edx jz 6f @@ -278,7 +337,7 @@ ENTRY(startup_32_smp) /* * Enable paging */ - movl $swapper_pg_dir-__PAGE_OFFSET,%eax + movl $pa(swapper_pg_dir),%eax movl %eax,%cr3 /* set the page table pointer.. */ movl %cr0,%eax orl $0x80000000,%eax @@ -556,8 +615,12 @@ ENTRY(_stext) .align PAGE_SIZE_asm ENTRY(swapper_pg_dir) .fill 1024,4,0 +#ifdef CONFIG_X86_PAE ENTRY(swapper_pg_pmd) .fill 1024,4,0 +#endif +ENTRY(swapper_pg_fixmap) + .fill 1024,4,0 ENTRY(empty_zero_page) .fill 4096,1,0