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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/arm/include/asm/cacheflush.h
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Diffstat (limited to 'arch/arm/include/asm/cacheflush.h')
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diff --git a/arch/arm/include/asm/cacheflush.h b/arch/arm/include/asm/cacheflush.h
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+/*
+ * 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_kern_louis()
+ *
+ * Flush data cache levels up to the level of unification
+ * inner shareable and invalidate the I-cache.
+ * Only needed from v7 onwards, falls back to flush_cache_all()
+ * for all other processor versions.
+ *
+ * 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_kern_louis)(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_kern_louis cpu_cache.flush_kern_louis
+#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_kern_louis(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();
+ dsb(ishst);
+}
+
+/*
+ * Flush caches up to Level of Unification Inner Shareable
+ */
+#define flush_cache_louis() __cpuc_flush_kern_louis()
+
+#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)
+{
+ struct mm_struct *mm = vma->vm_mm;
+
+ if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(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)
+{
+ struct mm_struct *mm = vma->vm_mm;
+
+ if (!mm || cpumask_test_cpu(smp_processor_id(), mm_cpumask(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(s,e) __cpuc_coherent_user_range(s,e)
+
+/*
+ * 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
+extern void flush_kernel_dcache_page(struct 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(ishst);
+}
+
+static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
+{
+ if (!cache_is_vipt_nonaliasing())
+ flush_cache_all();
+}
+
+/*
+ * Memory synchronization helpers for mixed cached vs non cached accesses.
+ *
+ * Some synchronization algorithms have to set states in memory with the
+ * cache enabled or disabled depending on the code path. It is crucial
+ * to always ensure proper cache maintenance to update main memory right
+ * away in that case.
+ *
+ * Any cached write must be followed by a cache clean operation.
+ * Any cached read must be preceded by a cache invalidate operation.
+ * Yet, in the read case, a cache flush i.e. atomic clean+invalidate
+ * operation is needed to avoid discarding possible concurrent writes to the
+ * accessed memory.
+ *
+ * Also, in order to prevent a cached writer from interfering with an
+ * adjacent non-cached writer, each state variable must be located to
+ * a separate cache line.
+ */
+
+/*
+ * This needs to be >= the max cache writeback size of all
+ * supported platforms included in the current kernel configuration.
+ * This is used to align state variables to their own cache lines.
+ */
+#define __CACHE_WRITEBACK_ORDER 6 /* guessed from existing platforms */
+#define __CACHE_WRITEBACK_GRANULE (1 << __CACHE_WRITEBACK_ORDER)
+
+/*
+ * There is no __cpuc_clean_dcache_area but we use it anyway for
+ * code intent clarity, and alias it to __cpuc_flush_dcache_area.
+ */
+#define __cpuc_clean_dcache_area __cpuc_flush_dcache_area
+
+/*
+ * Ensure preceding writes to *p by this CPU are visible to
+ * subsequent reads by other CPUs:
+ */
+static inline void __sync_cache_range_w(volatile void *p, size_t size)
+{
+ char *_p = (char *)p;
+
+ __cpuc_clean_dcache_area(_p, size);
+ outer_clean_range(__pa(_p), __pa(_p + size));
+}
+
+/*
+ * Ensure preceding writes to *p by other CPUs are visible to
+ * subsequent reads by this CPU. We must be careful not to
+ * discard data simultaneously written by another CPU, hence the
+ * usage of flush rather than invalidate operations.
+ */
+static inline void __sync_cache_range_r(volatile void *p, size_t size)
+{
+ char *_p = (char *)p;
+
+#ifdef CONFIG_OUTER_CACHE
+ if (outer_cache.flush_range) {
+ /*
+ * Ensure dirty data migrated from other CPUs into our cache
+ * are cleaned out safely before the outer cache is cleaned:
+ */
+ __cpuc_clean_dcache_area(_p, size);
+
+ /* Clean and invalidate stale data for *p from outer ... */
+ outer_flush_range(__pa(_p), __pa(_p + size));
+ }
+#endif
+
+ /* ... and inner cache: */
+ __cpuc_flush_dcache_area(_p, size);
+}
+
+#define sync_cache_w(ptr) __sync_cache_range_w(ptr, sizeof *(ptr))
+#define sync_cache_r(ptr) __sync_cache_range_r(ptr, sizeof *(ptr))
+
+/*
+ * Disabling cache access for one CPU in an ARMv7 SMP system is tricky.
+ * To do so we must:
+ *
+ * - Clear the SCTLR.C bit to prevent further cache allocations
+ * - Flush the desired level of cache
+ * - Clear the ACTLR "SMP" bit to disable local coherency
+ *
+ * ... and so without any intervening memory access in between those steps,
+ * not even to the stack.
+ *
+ * WARNING -- After this has been called:
+ *
+ * - No ldrex/strex (and similar) instructions must be used.
+ * - The CPU is obviously no longer coherent with the other CPUs.
+ * - This is unlikely to work as expected if Linux is running non-secure.
+ *
+ * Note:
+ *
+ * - This is known to apply to several ARMv7 processor implementations,
+ * however some exceptions may exist. Caveat emptor.
+ *
+ * - The clobber list is dictated by the call to v7_flush_dcache_*.
+ * fp is preserved to the stack explicitly prior disabling the cache
+ * since adding it to the clobber list is incompatible with having
+ * CONFIG_FRAME_POINTER=y. ip is saved as well if ever r12-clobbering
+ * trampoline are inserted by the linker and to keep sp 64-bit aligned.
+ */
+#define v7_exit_coherency_flush(level) \
+ asm volatile( \
+ ".arch armv7-a \n\t" \
+ "stmfd sp!, {fp, ip} \n\t" \
+ "mrc p15, 0, r0, c1, c0, 0 @ get SCTLR \n\t" \
+ "bic r0, r0, #"__stringify(CR_C)" \n\t" \
+ "mcr p15, 0, r0, c1, c0, 0 @ set SCTLR \n\t" \
+ "isb \n\t" \
+ "bl v7_flush_dcache_"__stringify(level)" \n\t" \
+ "mrc p15, 0, r0, c1, c0, 1 @ get ACTLR \n\t" \
+ "bic r0, r0, #(1 << 6) @ disable local coherency \n\t" \
+ "mcr p15, 0, r0, c1, c0, 1 @ set ACTLR \n\t" \
+ "isb \n\t" \
+ "dsb \n\t" \
+ "ldmfd sp!, {fp, ip}" \
+ : : : "r0","r1","r2","r3","r4","r5","r6","r7", \
+ "r9","r10","lr","memory" )
+
+int set_memory_ro(unsigned long addr, int numpages);
+int set_memory_rw(unsigned long addr, int numpages);
+int set_memory_x(unsigned long addr, int numpages);
+int set_memory_nx(unsigned long addr, int numpages);
+
+#ifdef CONFIG_DEBUG_RODATA
+void mark_rodata_ro(void);
+void set_kernel_text_rw(void);
+void set_kernel_text_ro(void);
+#else
+static inline void set_kernel_text_rw(void) { }
+static inline void set_kernel_text_ro(void) { }
+#endif
+
+void flush_uprobe_xol_access(struct page *page, unsigned long uaddr,
+ void *kaddr, unsigned long len);
+
+#endif