sparc64: Define VA hole at run time, rather than at compile time.

Now that we use 4-level page tables, we can provide up to 53-bits of
virtual address space to the user.

Adjust the VA hole based upon the capabilities of the cpu type probed.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Bob Picco <bob.picco@oracle.com>
This commit is contained in:
David S. Miller
2014-09-26 21:58:33 -07:00
parent ac55c76814
commit 4397bed080
2 changed files with 25 additions and 11 deletions

View File

@@ -102,21 +102,14 @@ typedef unsigned long pgprot_t;
typedef pte_t *pgtable_t;
/* These two values define the virtual address space range in which we
* must forbid 64-bit user processes from making mappings. It used to
* represent precisely the virtual address space hole present in most
* early sparc64 chips including UltraSPARC-I. But now it also is
* further constrained by the limits of our page tables, which is
* 43-bits of virtual address.
*/
#define SPARC64_VA_HOLE_TOP _AC(0xfffffc0000000000,UL)
#define SPARC64_VA_HOLE_BOTTOM _AC(0x0000040000000000,UL)
extern unsigned long sparc64_va_hole_top;
extern unsigned long sparc64_va_hole_bottom;
/* The next two defines specify the actual exclusion region we
* enforce, wherein we use a 4GB red zone on each side of the VA hole.
*/
#define VA_EXCLUDE_START (SPARC64_VA_HOLE_BOTTOM - (1UL << 32UL))
#define VA_EXCLUDE_END (SPARC64_VA_HOLE_TOP + (1UL << 32UL))
#define VA_EXCLUDE_START (sparc64_va_hole_bottom - (1UL << 32UL))
#define VA_EXCLUDE_END (sparc64_va_hole_top + (1UL << 32UL))
#define TASK_UNMAPPED_BASE (test_thread_flag(TIF_32BIT) ? \
_AC(0x0000000070000000,UL) : \