linux/arch/arm/include/asm/cacheflush.h
Will Deacon c5102f5935 ARM: 7408/1: cacheflush: return error to userspace when flushing syscall fails
The cacheflush syscall can fail for two reasons:

(1) The arguments are invalid (nonsensical address range or no VMA)

(2) The region generates a translation fault on a VIPT or PIPT cache

This patch allows do_cache_op to return an error code to userspace in
the case of the above. The various coherent_user_range implementations
are modified to return 0 in the case of VIVT caches or -EFAULT in the
case of an abort on v6/v7 cores.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-05-02 11:12:49 +01:00

348 lines
11 KiB
C

/*
* arch/arm/include/asm/cacheflush.h
*
* Copyright (C) 1999-2002 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_CACHEFLUSH_H
#define _ASMARM_CACHEFLUSH_H
#include <linux/mm.h>
#include <asm/glue-cache.h>
#include <asm/shmparam.h>
#include <asm/cachetype.h>
#include <asm/outercache.h>
#define CACHE_COLOUR(vaddr) ((vaddr & (SHMLBA - 1)) >> PAGE_SHIFT)
/*
* This flag is used to indicate that the page pointed to by a pte is clean
* and does not require cleaning before returning it to the user.
*/
#define PG_dcache_clean PG_arch_1
/*
* MM Cache Management
* ===================
*
* The arch/arm/mm/cache-*.S and arch/arm/mm/proc-*.S files
* implement these methods.
*
* Start addresses are inclusive and end addresses are exclusive;
* start addresses should be rounded down, end addresses up.
*
* See Documentation/cachetlb.txt for more information.
* Please note that the implementation of these, and the required
* effects are cache-type (VIVT/VIPT/PIPT) specific.
*
* flush_icache_all()
*
* Unconditionally clean and invalidate the entire icache.
* Currently only needed for cache-v6.S and cache-v7.S, see
* __flush_icache_all for the generic implementation.
*
* flush_kern_all()
*
* Unconditionally clean and invalidate the entire cache.
*
* flush_user_all()
*
* Clean and invalidate all user space cache entries
* before a change of page tables.
*
* flush_user_range(start, end, flags)
*
* Clean and invalidate a range of cache entries in the
* specified address space before a change of page tables.
* - start - user start address (inclusive, page aligned)
* - end - user end address (exclusive, page aligned)
* - flags - vma->vm_flags field
*
* coherent_kern_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
* - start - virtual start address
* - end - virtual end address
*
* coherent_user_range(start, end)
*
* Ensure coherency between the Icache and the Dcache in the
* region described by start, end. If you have non-snooping
* Harvard caches, you need to implement this function.
* - start - virtual start address
* - end - virtual end address
*
* flush_kern_dcache_area(kaddr, size)
*
* Ensure that the data held in page is written back.
* - kaddr - page address
* - size - region size
*
* DMA Cache Coherency
* ===================
*
* dma_flush_range(start, end)
*
* Clean and invalidate the specified virtual address range.
* - start - virtual start address
* - end - virtual end address
*/
struct cpu_cache_fns {
void (*flush_icache_all)(void);
void (*flush_kern_all)(void);
void (*flush_user_all)(void);
void (*flush_user_range)(unsigned long, unsigned long, unsigned int);
void (*coherent_kern_range)(unsigned long, unsigned long);
int (*coherent_user_range)(unsigned long, unsigned long);
void (*flush_kern_dcache_area)(void *, size_t);
void (*dma_map_area)(const void *, size_t, int);
void (*dma_unmap_area)(const void *, size_t, int);
void (*dma_flush_range)(const void *, const void *);
};
/*
* Select the calling method
*/
#ifdef MULTI_CACHE
extern struct cpu_cache_fns cpu_cache;
#define __cpuc_flush_icache_all cpu_cache.flush_icache_all
#define __cpuc_flush_kern_all cpu_cache.flush_kern_all
#define __cpuc_flush_user_all cpu_cache.flush_user_all
#define __cpuc_flush_user_range cpu_cache.flush_user_range
#define __cpuc_coherent_kern_range cpu_cache.coherent_kern_range
#define __cpuc_coherent_user_range cpu_cache.coherent_user_range
#define __cpuc_flush_dcache_area cpu_cache.flush_kern_dcache_area
/*
* These are private to the dma-mapping API. Do not use directly.
* Their sole purpose is to ensure that data held in the cache
* is visible to DMA, or data written by DMA to system memory is
* visible to the CPU.
*/
#define dmac_map_area cpu_cache.dma_map_area
#define dmac_unmap_area cpu_cache.dma_unmap_area
#define dmac_flush_range cpu_cache.dma_flush_range
#else
extern void __cpuc_flush_icache_all(void);
extern void __cpuc_flush_kern_all(void);
extern void __cpuc_flush_user_all(void);
extern void __cpuc_flush_user_range(unsigned long, unsigned long, unsigned int);
extern void __cpuc_coherent_kern_range(unsigned long, unsigned long);
extern int __cpuc_coherent_user_range(unsigned long, unsigned long);
extern void __cpuc_flush_dcache_area(void *, size_t);
/*
* These are private to the dma-mapping API. Do not use directly.
* Their sole purpose is to ensure that data held in the cache
* is visible to DMA, or data written by DMA to system memory is
* visible to the CPU.
*/
extern void dmac_map_area(const void *, size_t, int);
extern void dmac_unmap_area(const void *, size_t, int);
extern void dmac_flush_range(const void *, const void *);
#endif
/*
* Copy user data from/to a page which is mapped into a different
* processes address space. Really, we want to allow our "user
* space" model to handle this.
*/
extern void copy_to_user_page(struct vm_area_struct *, struct page *,
unsigned long, void *, const void *, unsigned long);
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
do { \
memcpy(dst, src, len); \
} while (0)
/*
* Convert calls to our calling convention.
*/
/* Invalidate I-cache */
#define __flush_icache_all_generic() \
asm("mcr p15, 0, %0, c7, c5, 0" \
: : "r" (0));
/* Invalidate I-cache inner shareable */
#define __flush_icache_all_v7_smp() \
asm("mcr p15, 0, %0, c7, c1, 0" \
: : "r" (0));
/*
* Optimized __flush_icache_all for the common cases. Note that UP ARMv7
* will fall through to use __flush_icache_all_generic.
*/
#if (defined(CONFIG_CPU_V7) && \
(defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K))) || \
defined(CONFIG_SMP_ON_UP)
#define __flush_icache_preferred __cpuc_flush_icache_all
#elif __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
#define __flush_icache_preferred __flush_icache_all_v7_smp
#elif __LINUX_ARM_ARCH__ == 6 && defined(CONFIG_ARM_ERRATA_411920)
#define __flush_icache_preferred __cpuc_flush_icache_all
#else
#define __flush_icache_preferred __flush_icache_all_generic
#endif
static inline void __flush_icache_all(void)
{
__flush_icache_preferred();
}
#define flush_cache_all() __cpuc_flush_kern_all()
static inline void vivt_flush_cache_mm(struct mm_struct *mm)
{
if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(mm)))
__cpuc_flush_user_all();
}
static inline void
vivt_flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
{
if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(vma->vm_mm)))
__cpuc_flush_user_range(start & PAGE_MASK, PAGE_ALIGN(end),
vma->vm_flags);
}
static inline void
vivt_flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn)
{
if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(vma->vm_mm))) {
unsigned long addr = user_addr & PAGE_MASK;
__cpuc_flush_user_range(addr, addr + PAGE_SIZE, vma->vm_flags);
}
}
#ifndef CONFIG_CPU_CACHE_VIPT
#define flush_cache_mm(mm) \
vivt_flush_cache_mm(mm)
#define flush_cache_range(vma,start,end) \
vivt_flush_cache_range(vma,start,end)
#define flush_cache_page(vma,addr,pfn) \
vivt_flush_cache_page(vma,addr,pfn)
#else
extern void flush_cache_mm(struct mm_struct *mm);
extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
extern void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsigned long pfn);
#endif
#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
/*
* flush_cache_user_range is used when we want to ensure that the
* Harvard caches are synchronised for the user space address range.
* This is used for the ARM private sys_cacheflush system call.
*/
#define flush_cache_user_range(start,end) \
__cpuc_coherent_user_range((start) & PAGE_MASK, PAGE_ALIGN(end))
/*
* Perform necessary cache operations to ensure that data previously
* stored within this range of addresses can be executed by the CPU.
*/
#define flush_icache_range(s,e) __cpuc_coherent_kern_range(s,e)
/*
* Perform necessary cache operations to ensure that the TLB will
* see data written in the specified area.
*/
#define clean_dcache_area(start,size) cpu_dcache_clean_area(start, size)
/*
* flush_dcache_page is used when the kernel has written to the page
* cache page at virtual address page->virtual.
*
* If this page isn't mapped (ie, page_mapping == NULL), or it might
* have userspace mappings, then we _must_ always clean + invalidate
* the dcache entries associated with the kernel mapping.
*
* Otherwise we can defer the operation, and clean the cache when we are
* about to change to user space. This is the same method as used on SPARC64.
* See update_mmu_cache for the user space part.
*/
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
extern void flush_dcache_page(struct page *);
static inline void flush_kernel_vmap_range(void *addr, int size)
{
if ((cache_is_vivt() || cache_is_vipt_aliasing()))
__cpuc_flush_dcache_area(addr, (size_t)size);
}
static inline void invalidate_kernel_vmap_range(void *addr, int size)
{
if ((cache_is_vivt() || cache_is_vipt_aliasing()))
__cpuc_flush_dcache_area(addr, (size_t)size);
}
#define ARCH_HAS_FLUSH_ANON_PAGE
static inline void flush_anon_page(struct vm_area_struct *vma,
struct page *page, unsigned long vmaddr)
{
extern void __flush_anon_page(struct vm_area_struct *vma,
struct page *, unsigned long);
if (PageAnon(page))
__flush_anon_page(vma, page, vmaddr);
}
#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
static inline void flush_kernel_dcache_page(struct page *page)
{
}
#define flush_dcache_mmap_lock(mapping) \
spin_lock_irq(&(mapping)->tree_lock)
#define flush_dcache_mmap_unlock(mapping) \
spin_unlock_irq(&(mapping)->tree_lock)
#define flush_icache_user_range(vma,page,addr,len) \
flush_dcache_page(page)
/*
* We don't appear to need to do anything here. In fact, if we did, we'd
* duplicate cache flushing elsewhere performed by flush_dcache_page().
*/
#define flush_icache_page(vma,page) do { } while (0)
/*
* flush_cache_vmap() is used when creating mappings (eg, via vmap,
* vmalloc, ioremap etc) in kernel space for pages. On non-VIPT
* caches, since the direct-mappings of these pages may contain cached
* data, we need to do a full cache flush to ensure that writebacks
* don't corrupt data placed into these pages via the new mappings.
*/
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
if (!cache_is_vipt_nonaliasing())
flush_cache_all();
else
/*
* set_pte_at() called from vmap_pte_range() does not
* have a DSB after cleaning the cache line.
*/
dsb();
}
static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
{
if (!cache_is_vipt_nonaliasing())
flush_cache_all();
}
#endif