diff options
Diffstat (limited to 'arch/x86/include/asm/processor.h')
| -rw-r--r-- | arch/x86/include/asm/processor.h | 38 |
1 files changed, 26 insertions, 12 deletions
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 6e0a3b43d027..6d0059c21969 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -330,8 +330,23 @@ struct x86_hw_tss { #define IO_BITMAP_BITS 65536 #define IO_BITMAP_BYTES (IO_BITMAP_BITS/8) #define IO_BITMAP_LONGS (IO_BITMAP_BYTES/sizeof(long)) -#define IO_BITMAP_OFFSET (offsetof(struct tss_struct, io_bitmap) - offsetof(struct tss_struct, x86_tss)) -#define INVALID_IO_BITMAP_OFFSET 0x8000 + +#define IO_BITMAP_OFFSET_VALID \ + (offsetof(struct tss_struct, io_bitmap) - \ + offsetof(struct tss_struct, x86_tss)) + +/* + * sizeof(unsigned long) coming from an extra "long" at the end + * of the iobitmap. + * + * -1? seg base+limit should be pointing to the address of the + * last valid byte + */ +#define __KERNEL_TSS_LIMIT \ + (IO_BITMAP_OFFSET_VALID + IO_BITMAP_BYTES + sizeof(unsigned long) - 1) + +/* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */ +#define IO_BITMAP_OFFSET_INVALID (__KERNEL_TSS_LIMIT + 1) struct entry_stack { unsigned long words[64]; @@ -350,6 +365,15 @@ struct tss_struct { struct x86_hw_tss x86_tss; /* + * Store the dirty size of the last io bitmap offender. The next + * one will have to do the cleanup as the switch out to a non io + * bitmap user will just set x86_tss.io_bitmap_base to a value + * outside of the TSS limit. So for sane tasks there is no need to + * actually touch the io_bitmap at all. + */ + unsigned int io_bitmap_prev_max; + + /* * The extra 1 is there because the CPU will access an * additional byte beyond the end of the IO permission * bitmap. The extra byte must be all 1 bits, and must @@ -360,16 +384,6 @@ struct tss_struct { DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw); -/* - * sizeof(unsigned long) coming from an extra "long" at the end - * of the iobitmap. - * - * -1? seg base+limit should be pointing to the address of the - * last valid byte - */ -#define __KERNEL_TSS_LIMIT \ - (IO_BITMAP_OFFSET + IO_BITMAP_BYTES + sizeof(unsigned long) - 1) - /* Per CPU interrupt stacks */ struct irq_stack { char stack[IRQ_STACK_SIZE]; |