linux-hardened/include/asm-arm/tlbflush.h
Daniel Jacobowitz 6a39dd6222 [ARM] 3759/2: Remove uses of %?
Patch from Daniel Jacobowitz

The ARM kernel has several uses of asm("foo%?").  %? is a GCC internal
modifier used to output conditional execution predicates.  However, no
version of GCC supports conditionalizing asm statements.  GCC 4.2 will
correctly expand %? to the empty string in user asms.  Earlier versions may
reuse the condition from the previous instruction.  In 'if (foo) asm
("bar%?");' this is somewhat likely to be right... but not reliable.

So, the only safe thing to do is to remove the uses of %?.  I believe
the tlbflush.h occurances were supposed to be removed before, based
on the comment about %? not working at the top of that file.

Old versions of GCC could omit branches around user asms if the asm didn't
mark the condition codes as clobbered.  This problem hasn't been seen on any
recent (3.x or 4.x) GCC, but it could theoretically happen.  So, where
%? was removed a cc clobber was added.

Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-20 14:58:35 +01:00

434 lines
12 KiB
C

/*
* linux/include/asm-arm/tlbflush.h
*
* Copyright (C) 1999-2003 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASMARM_TLBFLUSH_H
#define _ASMARM_TLBFLUSH_H
#ifndef CONFIG_MMU
#define tlb_flush(tlb) ((void) tlb)
#else /* CONFIG_MMU */
#include <asm/glue.h>
#define TLB_V3_PAGE (1 << 0)
#define TLB_V4_U_PAGE (1 << 1)
#define TLB_V4_D_PAGE (1 << 2)
#define TLB_V4_I_PAGE (1 << 3)
#define TLB_V6_U_PAGE (1 << 4)
#define TLB_V6_D_PAGE (1 << 5)
#define TLB_V6_I_PAGE (1 << 6)
#define TLB_V3_FULL (1 << 8)
#define TLB_V4_U_FULL (1 << 9)
#define TLB_V4_D_FULL (1 << 10)
#define TLB_V4_I_FULL (1 << 11)
#define TLB_V6_U_FULL (1 << 12)
#define TLB_V6_D_FULL (1 << 13)
#define TLB_V6_I_FULL (1 << 14)
#define TLB_V6_U_ASID (1 << 16)
#define TLB_V6_D_ASID (1 << 17)
#define TLB_V6_I_ASID (1 << 18)
#define TLB_DCLEAN (1 << 30)
#define TLB_WB (1 << 31)
/*
* MMU TLB Model
* =============
*
* We have the following to choose from:
* v3 - ARMv3
* v4 - ARMv4 without write buffer
* v4wb - ARMv4 with write buffer without I TLB flush entry instruction
* v4wbi - ARMv4 with write buffer with I TLB flush entry instruction
* v6wbi - ARMv6 with write buffer with I TLB flush entry instruction
*/
#undef _TLB
#undef MULTI_TLB
#define v3_tlb_flags (TLB_V3_FULL | TLB_V3_PAGE)
#ifdef CONFIG_CPU_TLB_V3
# define v3_possible_flags v3_tlb_flags
# define v3_always_flags v3_tlb_flags
# ifdef _TLB
# define MULTI_TLB 1
# else
# define _TLB v3
# endif
#else
# define v3_possible_flags 0
# define v3_always_flags (-1UL)
#endif
#define v4_tlb_flags (TLB_V4_U_FULL | TLB_V4_U_PAGE)
#ifdef CONFIG_CPU_TLB_V4WT
# define v4_possible_flags v4_tlb_flags
# define v4_always_flags v4_tlb_flags
# ifdef _TLB
# define MULTI_TLB 1
# else
# define _TLB v4
# endif
#else
# define v4_possible_flags 0
# define v4_always_flags (-1UL)
#endif
#define v4wbi_tlb_flags (TLB_WB | TLB_DCLEAN | \
TLB_V4_I_FULL | TLB_V4_D_FULL | \
TLB_V4_I_PAGE | TLB_V4_D_PAGE)
#ifdef CONFIG_CPU_TLB_V4WBI
# define v4wbi_possible_flags v4wbi_tlb_flags
# define v4wbi_always_flags v4wbi_tlb_flags
# ifdef _TLB
# define MULTI_TLB 1
# else
# define _TLB v4wbi
# endif
#else
# define v4wbi_possible_flags 0
# define v4wbi_always_flags (-1UL)
#endif
#define v4wb_tlb_flags (TLB_WB | TLB_DCLEAN | \
TLB_V4_I_FULL | TLB_V4_D_FULL | \
TLB_V4_D_PAGE)
#ifdef CONFIG_CPU_TLB_V4WB
# define v4wb_possible_flags v4wb_tlb_flags
# define v4wb_always_flags v4wb_tlb_flags
# ifdef _TLB
# define MULTI_TLB 1
# else
# define _TLB v4wb
# endif
#else
# define v4wb_possible_flags 0
# define v4wb_always_flags (-1UL)
#endif
#define v6wbi_tlb_flags (TLB_WB | TLB_DCLEAN | \
TLB_V6_I_FULL | TLB_V6_D_FULL | \
TLB_V6_I_PAGE | TLB_V6_D_PAGE | \
TLB_V6_I_ASID | TLB_V6_D_ASID)
#ifdef CONFIG_CPU_TLB_V6
# define v6wbi_possible_flags v6wbi_tlb_flags
# define v6wbi_always_flags v6wbi_tlb_flags
# ifdef _TLB
# define MULTI_TLB 1
# else
# define _TLB v6wbi
# endif
#else
# define v6wbi_possible_flags 0
# define v6wbi_always_flags (-1UL)
#endif
#ifndef _TLB
#error Unknown TLB model
#endif
#ifndef __ASSEMBLY__
struct cpu_tlb_fns {
void (*flush_user_range)(unsigned long, unsigned long, struct vm_area_struct *);
void (*flush_kern_range)(unsigned long, unsigned long);
unsigned long tlb_flags;
};
/*
* Select the calling method
*/
#ifdef MULTI_TLB
#define __cpu_flush_user_tlb_range cpu_tlb.flush_user_range
#define __cpu_flush_kern_tlb_range cpu_tlb.flush_kern_range
#else
#define __cpu_flush_user_tlb_range __glue(_TLB,_flush_user_tlb_range)
#define __cpu_flush_kern_tlb_range __glue(_TLB,_flush_kern_tlb_range)
extern void __cpu_flush_user_tlb_range(unsigned long, unsigned long, struct vm_area_struct *);
extern void __cpu_flush_kern_tlb_range(unsigned long, unsigned long);
#endif
extern struct cpu_tlb_fns cpu_tlb;
#define __cpu_tlb_flags cpu_tlb.tlb_flags
/*
* TLB Management
* ==============
*
* The arch/arm/mm/tlb-*.S files implement these methods.
*
* The TLB specific code is expected to perform whatever tests it
* needs to determine if it should invalidate the TLB for each
* call. Start addresses are inclusive and end addresses are
* exclusive; it is safe to round these addresses down.
*
* flush_tlb_all()
*
* Invalidate the entire TLB.
*
* flush_tlb_mm(mm)
*
* Invalidate all TLB entries in a particular address
* space.
* - mm - mm_struct describing address space
*
* flush_tlb_range(mm,start,end)
*
* Invalidate a range of TLB entries in the specified
* address space.
* - mm - mm_struct describing address space
* - start - start address (may not be aligned)
* - end - end address (exclusive, may not be aligned)
*
* flush_tlb_page(vaddr,vma)
*
* Invalidate the specified page in the specified address range.
* - vaddr - virtual address (may not be aligned)
* - vma - vma_struct describing address range
*
* flush_kern_tlb_page(kaddr)
*
* Invalidate the TLB entry for the specified page. The address
* will be in the kernels virtual memory space. Current uses
* only require the D-TLB to be invalidated.
* - kaddr - Kernel virtual memory address
*/
/*
* We optimise the code below by:
* - building a set of TLB flags that might be set in __cpu_tlb_flags
* - building a set of TLB flags that will always be set in __cpu_tlb_flags
* - if we're going to need __cpu_tlb_flags, access it once and only once
*
* This allows us to build optimal assembly for the single-CPU type case,
* and as close to optimal given the compiler constrants for multi-CPU
* case. We could do better for the multi-CPU case if the compiler
* implemented the "%?" method, but this has been discontinued due to too
* many people getting it wrong.
*/
#define possible_tlb_flags (v3_possible_flags | \
v4_possible_flags | \
v4wbi_possible_flags | \
v4wb_possible_flags | \
v6wbi_possible_flags)
#define always_tlb_flags (v3_always_flags & \
v4_always_flags & \
v4wbi_always_flags & \
v4wb_always_flags & \
v6wbi_always_flags)
#define tlb_flag(f) ((always_tlb_flags & (f)) || (__tlb_flag & possible_tlb_flags & (f)))
static inline void local_flush_tlb_all(void)
{
const int zero = 0;
const unsigned int __tlb_flag = __cpu_tlb_flags;
if (tlb_flag(TLB_WB))
asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V3_FULL))
asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V4_U_FULL | TLB_V6_U_FULL))
asm("mcr p15, 0, %0, c8, c7, 0" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V4_D_FULL | TLB_V6_D_FULL))
asm("mcr p15, 0, %0, c8, c6, 0" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V4_I_FULL | TLB_V6_I_FULL))
asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
}
static inline void local_flush_tlb_mm(struct mm_struct *mm)
{
const int zero = 0;
const int asid = ASID(mm);
const unsigned int __tlb_flag = __cpu_tlb_flags;
if (tlb_flag(TLB_WB))
asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");
if (cpu_isset(smp_processor_id(), mm->cpu_vm_mask)) {
if (tlb_flag(TLB_V3_FULL))
asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V4_U_FULL))
asm("mcr p15, 0, %0, c8, c7, 0" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V4_D_FULL))
asm("mcr p15, 0, %0, c8, c6, 0" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V4_I_FULL))
asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
}
if (tlb_flag(TLB_V6_U_ASID))
asm("mcr p15, 0, %0, c8, c7, 2" : : "r" (asid) : "cc");
if (tlb_flag(TLB_V6_D_ASID))
asm("mcr p15, 0, %0, c8, c6, 2" : : "r" (asid) : "cc");
if (tlb_flag(TLB_V6_I_ASID))
asm("mcr p15, 0, %0, c8, c5, 2" : : "r" (asid) : "cc");
}
static inline void
local_flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
{
const int zero = 0;
const unsigned int __tlb_flag = __cpu_tlb_flags;
uaddr = (uaddr & PAGE_MASK) | ASID(vma->vm_mm);
if (tlb_flag(TLB_WB))
asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero));
if (cpu_isset(smp_processor_id(), vma->vm_mm->cpu_vm_mask)) {
if (tlb_flag(TLB_V3_PAGE))
asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (uaddr) : "cc");
if (tlb_flag(TLB_V4_U_PAGE))
asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (uaddr) : "cc");
if (tlb_flag(TLB_V4_D_PAGE))
asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (uaddr) : "cc");
if (tlb_flag(TLB_V4_I_PAGE))
asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (uaddr) : "cc");
if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
}
if (tlb_flag(TLB_V6_U_PAGE))
asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (uaddr) : "cc");
if (tlb_flag(TLB_V6_D_PAGE))
asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (uaddr) : "cc");
if (tlb_flag(TLB_V6_I_PAGE))
asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (uaddr) : "cc");
}
static inline void local_flush_tlb_kernel_page(unsigned long kaddr)
{
const int zero = 0;
const unsigned int __tlb_flag = __cpu_tlb_flags;
kaddr &= PAGE_MASK;
if (tlb_flag(TLB_WB))
asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V3_PAGE))
asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (kaddr) : "cc");
if (tlb_flag(TLB_V4_U_PAGE))
asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (kaddr) : "cc");
if (tlb_flag(TLB_V4_D_PAGE))
asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (kaddr) : "cc");
if (tlb_flag(TLB_V4_I_PAGE))
asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (kaddr) : "cc");
if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
if (tlb_flag(TLB_V6_U_PAGE))
asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (kaddr) : "cc");
if (tlb_flag(TLB_V6_D_PAGE))
asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (kaddr) : "cc");
if (tlb_flag(TLB_V6_I_PAGE))
asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (kaddr) : "cc");
/* The ARM ARM states that the completion of a TLB maintenance
* operation is only guaranteed by a DSB instruction
*/
if (tlb_flag(TLB_V6_U_PAGE | TLB_V6_D_PAGE | TLB_V6_I_PAGE))
asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (zero) : "cc");
}
/*
* flush_pmd_entry
*
* Flush a PMD entry (word aligned, or double-word aligned) to
* RAM if the TLB for the CPU we are running on requires this.
* This is typically used when we are creating PMD entries.
*
* clean_pmd_entry
*
* Clean (but don't drain the write buffer) if the CPU requires
* these operations. This is typically used when we are removing
* PMD entries.
*/
static inline void flush_pmd_entry(pmd_t *pmd)
{
const unsigned int zero = 0;
const unsigned int __tlb_flag = __cpu_tlb_flags;
if (tlb_flag(TLB_DCLEAN))
asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pmd"
: : "r" (pmd) : "cc");
if (tlb_flag(TLB_WB))
asm("mcr p15, 0, %0, c7, c10, 4 @ flush_pmd"
: : "r" (zero) : "cc");
}
static inline void clean_pmd_entry(pmd_t *pmd)
{
const unsigned int __tlb_flag = __cpu_tlb_flags;
if (tlb_flag(TLB_DCLEAN))
asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pmd"
: : "r" (pmd) : "cc");
}
#undef tlb_flag
#undef always_tlb_flags
#undef possible_tlb_flags
/*
* Convert calls to our calling convention.
*/
#define local_flush_tlb_range(vma,start,end) __cpu_flush_user_tlb_range(start,end,vma)
#define local_flush_tlb_kernel_range(s,e) __cpu_flush_kern_tlb_range(s,e)
#ifndef CONFIG_SMP
#define flush_tlb_all local_flush_tlb_all
#define flush_tlb_mm local_flush_tlb_mm
#define flush_tlb_page local_flush_tlb_page
#define flush_tlb_kernel_page local_flush_tlb_kernel_page
#define flush_tlb_range local_flush_tlb_range
#define flush_tlb_kernel_range local_flush_tlb_kernel_range
#else
extern void flush_tlb_all(void);
extern void flush_tlb_mm(struct mm_struct *mm);
extern void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr);
extern void flush_tlb_kernel_page(unsigned long kaddr);
extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
#endif
/*
* if PG_dcache_dirty is set for the page, we need to ensure that any
* cache entries for the kernels virtual memory range are written
* back to the page.
*/
extern void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, pte_t pte);
/*
* ARM processors do not cache TLB tables in RAM.
*/
#define flush_tlb_pgtables(mm,start,end) do { } while (0)
#endif
#endif /* CONFIG_MMU */
#endif