[PATCH 16/33] x86_64: Assembly safe page.h and pgtable.h

Eric W. Biederman
2006-08-01T11:12:11Z

This patch makes pgtable.h and page.h safe to include
in assembly files like head.S. Allowing us to use
symbolic constants instead of hard coded numbers when
refering to the page tables.

This patch copies asm-sparc64/const.h to asm-x86_64 to
get a definition of _AC() a very convinient macro that
allows us to force the type when we are compiling the
code in C and to drop all of the type information when
we are using the constant in assembly. Previously this
was done with multiple definition of the same constant.
const.h was modified slightly so that it works when given
CONFIG options as arguments.

This patch adds #ifndef __ASSEMBLY__ ... #endif
and _AC(1,UL) where appropriate so the assembler won't
choke on the header files. Otherwise nothing
should have changed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
include/asm-x86_64/const.h | 20 ++++++++++++++++++++
include/asm-x86_64/page.h | 34 +++++++++++++---------------------
include/asm-x86_64/pgtable.h | 33 +++++++++++++++++++++------------
3 files changed, 54 insertions(+), 33 deletions(-)

diff --git a/include/asm-x86_64/const.h b/include/asm-x86_64/const.h
new file mode 100644
index 0000000..54fb08f
--- /dev/null
+++ b/include/asm-x86_64/const.h
@@ -0,0 +1,20 @@
+/* const.h: Macros for dealing with constants. */
+
+#ifndef _X86_64_CONST_H
+#define _X86_64_CONST_H
+
+/* Some constant macros are used in both assembler and
+ * C code. Therefore we cannot annotate them always with
+ * 'UL' and other type specificers unilaterally. We
+ * use the following macros to deal with this.
+ */
+
+#ifdef __ASSEMBLY__
+#define _AC(X,Y) X
+#else
+#define __AC(X,Y) (X##Y)
+#define _AC(X,Y) __AC(X,Y)
+#endif
+
+
+#endif /* !(_X86_64_CONST_H) */
diff --git a/include/asm-x86_64/page.h b/include/asm-x86_64/page.h
index 10f3461..f030260 100644
--- a/include/asm-x86_64/page.h
+++ b/include/asm-x86_64/page.h
@@ -1,14 +1,11 @@
#ifndef _X86_64_PAGE_H
#define _X86_64_PAGE_H

+#include <asm/const.h>

/* PAGE_SHIFT determines the page size */
#define PAGE_SHIFT 12
-#ifdef __ASSEMBLY__
-#define PAGE_SIZE (0x1 << PAGE_SHIFT)
-#else
-#define PAGE_SIZE (1UL << PAGE_SHIFT)
-#endif
+#define PAGE_SIZE (_AC(1,UL) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
#define PHYSICAL_PAGE_MASK (~(PAGE_SIZE-1) & __PHYSICAL_MASK)

@@ -33,10 +30,10 @@ #define MCE_STACK 5
#define N_EXCEPTION_STACKS 5 /* hw limit: 7 */

#define LARGE_PAGE_MASK (~(LARGE_PAGE_SIZE-1))
-#define LARGE_PAGE_SIZE (1UL << PMD_SHIFT)
+#define LARGE_PAGE_SIZE (_AC(1,UL) << PMD_SHIFT)

#define HPAGE_SHIFT PMD_SHIFT
-#define HPAGE_SIZE ((1UL) << HPAGE_SHIFT)
+#define HPAGE_SIZE (_AC(1,UL) << HPAGE_SHIFT)
#define HPAGE_MASK (~(HPAGE_SIZE - 1))
#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)

@@ -76,29 +73,24 @@ #define __pud(x) ((pud_t) { (x) } )
#define __pgd(x) ((pgd_t) { (x) } )
#define __pgprot(x) ((pgprot_t) { (x) } )

-#define __PHYSICAL_START ((unsigned long)CONFIG_PHYSICAL_START)
-#define __START_KERNEL (__START_KERNEL_map + __PHYSICAL_START)
-#define __START_KERNEL_map 0xffffffff80000000UL
-#define __PAGE_OFFSET 0xffff810000000000UL
+#endif /* !__ASSEMBLY__ */

-#else
-#define __PHYSICAL_START CONFIG_PHYSICAL_START
+#define __PHYSICAL_START _AC(CONFIG_PHYSICAL_START,UL)
#define __START_KERNEL (__START_KERNEL_map + __PHYSICAL_START)
-#define __START_KERNEL_map 0xffffffff80000000
-#define __PAGE_OFFSET 0xffff810000000000
-#endif /* !__ASSEMBLY__ */
+#define __START_KERNEL_map _AC(0xffffffff80000000,UL)
+#define __PAGE_OFFSET _AC(0xffff810000000000,UL)

/* to align the pointer to the (next) page boundary */
#define PAGE_ALIGN(addr) (((addr)+PAGE_SIZE-1)&PAGE_MASK)

/* See Documentation/x86_64/mm.txt for a description of the memory map. */
#define __PHYSICAL_MASK_SHIFT 46
-#define __PHYSICAL_MASK ((1UL << __PHYSICAL_MASK_SHIFT) - 1)
+#define __PHYSICAL_MASK ((_AC(1,UL) << __PHYSICAL_MASK_SHIFT) - 1)
#define __VIRTUAL_MASK_SHIFT 48
-#define __VIRTUAL_MASK ((1UL << __VIRTUAL_MASK_SHIFT) - 1)
+#define __VIRTUAL_MASK ((_AC(1,UL) << __VIRTUAL_MASK_SHIFT) - 1)

-#define KERNEL_TEXT_SIZE (40UL*1024*1024)
-#define KERNEL_TEXT_START 0xffffffff80000000UL
+#define KERNEL_TEXT_SIZE (_AC(40,UL)*1024*1024)
+#define KERNEL_TEXT_START _AC(0xffffffff80000000,UL)

#ifndef __ASSEMBLY__

@@ -106,7 +98,7 @@ #include <asm/bug.h>

#endif /* __ASSEMBLY__ */

-#define PAGE_OFFSET ((unsigned long)__PAGE_OFFSET)
+#define PAGE_OFFSET __PAGE_OFFSET

/* Note: __pa(&symbol_visible_to_c) should be always replaced with __pa_symbol.
Otherwise you risk miscompilation. */
diff --git a/include/asm-x86_64/pgtable.h b/include/asm-x86_64/pgtable.h
index a31ab4e..211a2ca 100644
--- a/include/asm-x86_64/pgtable.h
+++ b/include/asm-x86_64/pgtable.h
@@ -1,6 +1,9 @@
#ifndef _X86_64_PGTABLE_H
#define _X86_64_PGTABLE_H

+#include <asm/const.h>
+#ifndef __ASSEMBLY__
+
/*
* This file contains the functions and defines necessary to modify and use
* the x86-64 page table tree.
@@ -34,6 +37,8 @@ extern unsigned long pgkern_mask;
extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))

+#endif /* !__ASSEMBLY__ */
+
/*
* PGDIR_SHIFT determines what a top-level page table entry can map
*/
@@ -58,6 +63,8 @@ #define PTRS_PER_PMD 512
*/
#define PTRS_PER_PTE 512

+#ifndef __ASSEMBLY__
+
#define pte_ERROR(e) \
printk("%s:%d: bad pte %p(%016lx).\n", __FILE__, __LINE__, &(e), pte_val(e))
#define pmd_ERROR(e) \
@@ -124,22 +131,23 @@ #define pte_same(a, b) ((a).pte == (b).

#define pte_pgprot(a) (__pgprot((a).pte & ~PHYSICAL_PAGE_MASK))

-#define PMD_SIZE (1UL << PMD_SHIFT)
+#endif /* !__ASSEMBLY__ */
+
+#define PMD_SIZE (_AC(1,UL) << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
-#define PUD_SIZE (1UL << PUD_SHIFT)
+#define PUD_SIZE (_AC(1,UL) << PUD_SHIFT)
#define PUD_MASK (~(PUD_SIZE-1))
-#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
+#define PGDIR_SIZE (_AC(1,UL) << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))

#define USER_PTRS_PER_PGD ((TASK_SIZE-1)/PGDIR_SIZE+1)
#define FIRST_USER_ADDRESS 0

-#ifndef __ASSEMBLY__
-#define MAXMEM 0x3fffffffffffUL
-#define VMALLOC_START 0xffffc20000000000UL
-#define VMALLOC_END 0xffffe1ffffffffffUL
-#define MODULES_VADDR 0xffffffff88000000UL
-#define MODULES_END 0xfffffffffff00000UL
+#define MAXMEM _AC(0x3fffffffffff,UL)
+#define VMALLOC_START _AC(0xffffc20000000000,UL)
+#define VMALLOC_END _AC(0xffffe1ffffffffff,UL)
+#define MODULES_VADDR _AC(0xffffffff88000000,UL)
+#define MODULES_END _AC(0xfffffffffff00000,UL)
#define MODULES_LEN (MODULES_END - MODULES_VADDR)

#define _PAGE_BIT_PRESENT 0
@@ -165,7 +173,7 @@ #define _PAGE_FILE 0x040 /* nonlinear fi
#define _PAGE_GLOBAL 0x100 /* Global TLB entry */

#define _PAGE_PROTNONE 0x080 /* If not present */
-#define _PAGE_NX (1UL<<_PAGE_BIT_NX)
+#define _PAGE_NX (_AC(1,UL)<<_PAGE_BIT_NX)

#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
@@ -227,6 +235,8 @@ #define __S101 PAGE_READONLY_EXEC
#define __S110 PAGE_SHARED_EXEC
#define __S111 PAGE_SHARED_EXEC

+#ifndef __ASSEMBLY__
+
static inline unsigned long pgd_bad(pgd_t pgd)
{
unsigned long val = pgd_val(pgd);
@@ -418,8 +428,6 @@ extern spinlock_t pgd_lock;
extern struct page *pgd_list;
void vmalloc_sync_all(void);

-#endif /* !__ASSEMBLY__ */
-
extern int kern_addr_valid(unsigned long addr);

#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
@@ -449,5 +457,6 @@ #define __HAVE_ARCH_PTEP_GET_AND_CLEAR_F
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
#define __HAVE_ARCH_PTE_SAME
#include <asm-generic/pgtable.h>
+#endif /* !__ASSEMBLY__ */

#endif /* _X86_64_PGTABLE_H */
--
1.4.2.rc2.g5209e