*/
.text
-#include <linux/config.h>
#include <linux/threads.h>
#include <linux/linkage.h>
#include <asm/segment.h>
/*
* This is how much memory *in addition to the memory covered up to
- * and including _end* we need mapped initially. We need one bit for
- * each possible page, but only in low memory, which means
- * 2^32/4096/8 = 128K worst case (4G/4G split.)
+ * and including _end* we need mapped initially.
+ * We need:
+ * - one bit for each possible page, but only in low memory, which means
+ * 2^32/4096/8 = 128K worst case (4G/4G split.)
+ * - enough space to map all low memory, which means
+ * (2^32/4096) / 1024 pages (worst case, non PAE)
+ * (2^32/4096) / 512 + 4 pages (worst case for PAE)
+ * - a few pages for allocator use before the kernel pagetable has
+ * been set up
*
* Modulo rounding, each megabyte assigned here requires a kilobyte of
* memory, which is currently unreclaimed.
*
* This should be a multiple of a page.
*/
-#define INIT_MAP_BEYOND_END (128*1024)
+LOW_PAGES = 1<<(32-PAGE_SHIFT_asm)
+#if PTRS_PER_PMD > 1
+PAGE_TABLE_SIZE = (LOW_PAGES / PTRS_PER_PMD) + PTRS_PER_PGD
+#else
+PAGE_TABLE_SIZE = (LOW_PAGES / PTRS_PER_PGD)
+#endif
+BOOTBITMAP_SIZE = LOW_PAGES / 8
+ALLOCATOR_SLOP = 4
+
+INIT_MAP_BEYOND_END = BOOTBITMAP_SIZE + (PAGE_TABLE_SIZE + ALLOCATOR_SLOP)*PAGE_SIZE_asm
/*
* 32-bit kernel entrypoint; only used by the boot CPU. On entry,
* any particular GDT layout, because we load our own as soon as we
* can.
*/
+.section .text.head,"ax",@progbits
ENTRY(startup_32)
/*
movzwl OLD_CL_OFFSET,%esi
addl $(OLD_CL_BASE_ADDR),%esi
2:
- movl $(saved_command_line - __PAGE_OFFSET),%edi
+ movl $(boot_command_line - __PAGE_OFFSET),%edi
movl $(COMMAND_LINE_SIZE/4),%ecx
rep
movsl
jb 10b
movl %edi,(init_pg_tables_end - __PAGE_OFFSET)
-#ifdef CONFIG_SMP
xorl %ebx,%ebx /* This is the boot CPU (BSP) */
jmp 3f
-
/*
* Non-boot CPU entry point; entered from trampoline.S
* We can't lgdt here, because lgdt itself uses a data segment, but
- * we know the trampoline has already loaded the boot_gdt_table GDT
- * for us.
+ * we know the trampoline has already loaded the boot_gdt for us.
+ *
+ * If cpu hotplug is not supported then this code can go in init section
+ * which will be freed later
*/
+
+#ifdef CONFIG_HOTPLUG_CPU
+.section .text,"ax",@progbits
+#else
+.section .init.text,"ax",@progbits
+#endif
+
+#ifdef CONFIG_SMP
ENTRY(startup_32_smp)
cld
movl $(__BOOT_DS),%eax
xorl %ebx,%ebx
incl %ebx
-3:
#endif /* CONFIG_SMP */
+3:
/*
* Enable paging
movl %eax,%cr0
call check_x87
- lgdt cpu_gdt_descr
+ lgdt early_gdt_descr
lidt idt_descr
ljmp $(__KERNEL_CS),$1f
1: movl $(__KERNEL_DS),%eax # reload all the segment registers
movl %eax,%ss # after changing gdt.
+ movl %eax,%fs # gets reset once there's real percpu
movl $(__USER_DS),%eax # DS/ES contains default USER segment
movl %eax,%ds
movl %eax,%es
- xorl %eax,%eax # Clear FS/GS and LDT
- movl %eax,%fs
+ xorl %eax,%eax # Clear GS and LDT
movl %eax,%gs
lldt %ax
+
cld # gcc2 wants the direction flag cleared at all times
+ pushl $0 # fake return address for unwinder
#ifdef CONFIG_SMP
movb ready, %cl
movb $1, ready
- cmpb $0,%cl
- je 1f # the first CPU calls start_kernel
- # all other CPUs call initialize_secondary
- call initialize_secondary
- jmp L6
+ cmpb $0,%cl # the first CPU calls start_kernel
+ je 1f
+ movl $(__KERNEL_PERCPU), %eax
+ movl %eax,%fs # set this cpu's percpu
+ jmp initialize_secondary # all other CPUs call initialize_secondary
1:
#endif /* CONFIG_SMP */
- call start_kernel
-L6:
- jmp L6 # main should never return here, but
- # just in case, we know what happens.
+ jmp start_kernel
/*
* We depend on ET to be correct. This checks for 287/387.
addl $8,%edi
dec %ecx
jne rp_sidt
+
+.macro set_early_handler handler,trapno
+ lea \handler,%edx
+ movl $(__KERNEL_CS << 16),%eax
+ movw %dx,%ax
+ movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
+ lea idt_table,%edi
+ movl %eax,8*\trapno(%edi)
+ movl %edx,8*\trapno+4(%edi)
+.endm
+
+ set_early_handler handler=early_divide_err,trapno=0
+ set_early_handler handler=early_illegal_opcode,trapno=6
+ set_early_handler handler=early_protection_fault,trapno=13
+ set_early_handler handler=early_page_fault,trapno=14
+
ret
+early_divide_err:
+ xor %edx,%edx
+ pushl $0 /* fake errcode */
+ jmp early_fault
+
+early_illegal_opcode:
+ movl $6,%edx
+ pushl $0 /* fake errcode */
+ jmp early_fault
+
+early_protection_fault:
+ movl $13,%edx
+ jmp early_fault
+
+early_page_fault:
+ movl $14,%edx
+ jmp early_fault
+
+early_fault:
+ cld
+#ifdef CONFIG_PRINTK
+ movl $(__KERNEL_DS),%eax
+ movl %eax,%ds
+ movl %eax,%es
+ cmpl $2,early_recursion_flag
+ je hlt_loop
+ incl early_recursion_flag
+ movl %cr2,%eax
+ pushl %eax
+ pushl %edx /* trapno */
+ pushl $fault_msg
+#ifdef CONFIG_EARLY_PRINTK
+ call early_printk
+#else
+ call printk
+#endif
+#endif
+hlt_loop:
+ hlt
+ jmp hlt_loop
+
/* This is the default interrupt "handler" :-) */
ALIGN
ignore_int:
movl $(__KERNEL_DS),%eax
movl %eax,%ds
movl %eax,%es
+ cmpl $2,early_recursion_flag
+ je hlt_loop
+ incl early_recursion_flag
pushl 16(%esp)
pushl 24(%esp)
pushl 32(%esp)
#endif
iret
+.section .text
/*
* Real beginning of normal "text" segment
*/
* This starts the data section.
*/
.data
-
ENTRY(stack_start)
.long init_thread_union+THREAD_SIZE
.long __BOOT_DS
ready: .byte 0
+early_recursion_flag:
+ .long 0
+
int_msg:
.asciz "Unknown interrupt or fault at EIP %p %p %p\n"
+fault_msg:
+ .ascii "Int %d: CR2 %p err %p EIP %p CS %p flags %p\n"
+ .asciz "Stack: %p %p %p %p %p %p %p %p\n"
+
/*
* The IDT and GDT 'descriptors' are a strange 48-bit object
* only used by the lidt and lgdt instructions. They are not
.globl boot_gdt_descr
.globl idt_descr
-.globl cpu_gdt_descr
ALIGN
# early boot GDT descriptor (must use 1:1 address mapping)
.word 0 # 32 bit align gdt_desc.address
boot_gdt_descr:
.word __BOOT_DS+7
- .long boot_gdt_table - __PAGE_OFFSET
+ .long boot_gdt - __PAGE_OFFSET
.word 0 # 32-bit align idt_desc.address
idt_descr:
# boot GDT descriptor (later on used by CPU#0):
.word 0 # 32 bit align gdt_desc.address
-cpu_gdt_descr:
+ENTRY(early_gdt_descr)
.word GDT_ENTRIES*8-1
- .long cpu_gdt_table
-
- .fill NR_CPUS-1,8,0 # space for the other GDT descriptors
+ .long per_cpu__gdt_page /* Overwritten for secondary CPUs */
/*
- * The boot_gdt_table must mirror the equivalent in setup.S and is
+ * The boot_gdt must mirror the equivalent in setup.S and is
* used only for booting.
*/
.align L1_CACHE_BYTES
-ENTRY(boot_gdt_table)
+ENTRY(boot_gdt)
.fill GDT_ENTRY_BOOT_CS,8,0
.quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */
.quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */
-
-/*
- * The Global Descriptor Table contains 28 quadwords, per-CPU.
- */
- .align PAGE_SIZE_asm
-ENTRY(cpu_gdt_table)
- .quad 0x0000000000000000 /* NULL descriptor */
- .quad 0x0000000000000000 /* 0x0b reserved */
- .quad 0x0000000000000000 /* 0x13 reserved */
- .quad 0x0000000000000000 /* 0x1b reserved */
- .quad 0x0000000000000000 /* 0x20 unused */
- .quad 0x0000000000000000 /* 0x28 unused */
- .quad 0x0000000000000000 /* 0x33 TLS entry 1 */
- .quad 0x0000000000000000 /* 0x3b TLS entry 2 */
- .quad 0x0000000000000000 /* 0x43 TLS entry 3 */
- .quad 0x0000000000000000 /* 0x4b reserved */
- .quad 0x0000000000000000 /* 0x53 reserved */
- .quad 0x0000000000000000 /* 0x5b reserved */
-
- .quad 0x00cf9a000000ffff /* 0x60 kernel 4GB code at 0x00000000 */
- .quad 0x00cf92000000ffff /* 0x68 kernel 4GB data at 0x00000000 */
- .quad 0x00cffa000000ffff /* 0x73 user 4GB code at 0x00000000 */
- .quad 0x00cff2000000ffff /* 0x7b user 4GB data at 0x00000000 */
-
- .quad 0x0000000000000000 /* 0x80 TSS descriptor */
- .quad 0x0000000000000000 /* 0x88 LDT descriptor */
-
- /*
- * Segments used for calling PnP BIOS have byte granularity.
- * They code segments and data segments have fixed 64k limits,
- * the transfer segment sizes are set at run time.
- */
- .quad 0x00409a000000ffff /* 0x90 32-bit code */
- .quad 0x00009a000000ffff /* 0x98 16-bit code */
- .quad 0x000092000000ffff /* 0xa0 16-bit data */
- .quad 0x0000920000000000 /* 0xa8 16-bit data */
- .quad 0x0000920000000000 /* 0xb0 16-bit data */
-
- /*
- * The APM segments have byte granularity and their bases
- * are set at run time. All have 64k limits.
- */
- .quad 0x00409a000000ffff /* 0xb8 APM CS code */
- .quad 0x00009a000000ffff /* 0xc0 APM CS 16 code (16 bit) */
- .quad 0x004092000000ffff /* 0xc8 APM DS data */
-
- .quad 0x0000920000000000 /* 0xd0 - ESPFIX 16-bit SS */
- .quad 0x0000000000000000 /* 0xd8 - unused */
- .quad 0x0000000000000000 /* 0xe0 - unused */
- .quad 0x0000000000000000 /* 0xe8 - unused */
- .quad 0x0000000000000000 /* 0xf0 - unused */
- .quad 0x0000000000000000 /* 0xf8 - GDT entry 31: double-fault TSS */
-