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diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Based on arch/arm/include/asm/cacheflush.h
+ *
+ * Copyright (C) 1999-2002 Russell King.
+ * Copyright (C) 2012 ARM Ltd.
+ */
+#ifndef __ASM_CACHEFLUSH_H
+#define __ASM_CACHEFLUSH_H
+
+#include <linux/kgdb.h>
+#include <linux/mm.h>
+
+/*
+ * 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/arm64/mm/cache.S implements these methods.
+ *
+ * Start addresses are inclusive and end addresses are exclusive; start
+ * addresses should be rounded down, end addresses up.
+ *
+ * See Documentation/core-api/cachetlb.rst for more information. Please note that
+ * the implementation assumes non-aliasing VIPT D-cache and (aliasing)
+ * VIPT I-cache.
+ *
+ * All functions below apply to the interval [start, end)
+ * - start - virtual start address (inclusive)
+ * - end - virtual end address (exclusive)
+ *
+ * caches_clean_inval_pou(start, end)
+ *
+ * Ensure coherency between the I-cache and the D-cache region to
+ * the Point of Unification.
+ *
+ * caches_clean_inval_user_pou(start, end)
+ *
+ * Ensure coherency between the I-cache and the D-cache region to
+ * the Point of Unification.
+ * Use only if the region might access user memory.
+ *
+ * icache_inval_pou(start, end)
+ *
+ * Invalidate I-cache region to the Point of Unification.
+ *
+ * dcache_clean_inval_poc(start, end)
+ *
+ * Clean and invalidate D-cache region to the Point of Coherency.
+ *
+ * dcache_inval_poc(start, end)
+ *
+ * Invalidate D-cache region to the Point of Coherency.
+ *
+ * dcache_clean_poc(start, end)
+ *
+ * Clean D-cache region to the Point of Coherency.
+ *
+ * dcache_clean_pop(start, end)
+ *
+ * Clean D-cache region to the Point of Persistence.
+ *
+ * dcache_clean_pou(start, end)
+ *
+ * Clean D-cache region to the Point of Unification.
+ */
+extern void caches_clean_inval_pou(unsigned long start, unsigned long end);
+extern void icache_inval_pou(unsigned long start, unsigned long end);
+extern void dcache_clean_inval_poc(unsigned long start, unsigned long end);
+extern void dcache_inval_poc(unsigned long start, unsigned long end);
+extern void dcache_clean_poc(unsigned long start, unsigned long end);
+extern void dcache_clean_pop(unsigned long start, unsigned long end);
+extern void dcache_clean_pou(unsigned long start, unsigned long end);
+extern long caches_clean_inval_user_pou(unsigned long start, unsigned long end);
+extern void sync_icache_aliases(unsigned long start, unsigned long end);
+
+static inline void flush_icache_range(unsigned long start, unsigned long end)
+{
+ caches_clean_inval_pou(start, end);
+
+ /*
+ * IPI all online CPUs so that they undergo a context synchronization
+ * event and are forced to refetch the new instructions.
+ */
+
+ /*
+ * KGDB performs cache maintenance with interrupts disabled, so we
+ * will deadlock trying to IPI the secondary CPUs. In theory, we can
+ * set CACHE_FLUSH_IS_SAFE to 0 to avoid this known issue, but that
+ * just means that KGDB will elide the maintenance altogether! As it
+ * turns out, KGDB uses IPIs to round-up the secondary CPUs during
+ * the patching operation, so we don't need extra IPIs here anyway.
+ * In which case, add a KGDB-specific bodge and return early.
+ */
+ if (in_dbg_master())
+ return;
+
+ kick_all_cpus_sync();
+}
+#define flush_icache_range flush_icache_range
+
+/*
+ * 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_to_user_page copy_to_user_page
+
+/*
+ * 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 __always_inline void icache_inval_all_pou(void)
+{
+ if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC))
+ return;
+
+ asm("ic ialluis");
+ dsb(ish);
+}
+
+#include <asm-generic/cacheflush.h>
+
+#endif /* __ASM_CACHEFLUSH_H */