Initial commit: OpenHarmony-v4.0-ReleaseOpenHarmony-v4.0-Release

1 files changed, 94 insertions, 0 deletions

diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
new file mode 100644
index 000000000..5fec7f45d
--- /dev/null
+++ b/arch/mips/mm/highmem.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/compiler.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/highmem.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <asm/fixmap.h>
+#include <asm/tlbflush.h>
+
+static pte_t *kmap_pte;
+
+unsigned long highstart_pfn, highend_pfn;
+
+void kmap_flush_tlb(unsigned long addr)
+{
+        flush_tlb_one(addr);
+}
+EXPORT_SYMBOL(kmap_flush_tlb);
+
+void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
+{
+        unsigned long vaddr;
+        int idx, type;
+
+        type = kmap_atomic_idx_push();
+        idx = type + KM_TYPE_NR*smp_processor_id();
+        vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+        BUG_ON(!pte_none(*(kmap_pte - idx)));
+#endif
+        set_pte(kmap_pte-idx, mk_pte(page, prot));
+        local_flush_tlb_one((unsigned long)vaddr);
+
+        return (void*) vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic_high_prot);
+
+void kunmap_atomic_high(void *kvaddr)
+{
+        unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
+        int type __maybe_unused;
+
+        if (vaddr < FIXADDR_START)
+                return;
+
+        type = kmap_atomic_idx();
+#ifdef CONFIG_DEBUG_HIGHMEM
+        {
+                int idx = type + KM_TYPE_NR * smp_processor_id();
+
+                BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+                /*
+                 * force other mappings to Oops if they'll try to access
+                 * this pte without first remap it
+                 */
+                pte_clear(&init_mm, vaddr, kmap_pte-idx);
+                local_flush_tlb_one(vaddr);
+        }
+#endif
+        kmap_atomic_idx_pop();
+}
+EXPORT_SYMBOL(kunmap_atomic_high);
+
+/*
+ * This is the same as kmap_atomic() but can map memory that doesn't
+ * have a struct page associated with it.
+ */
+void *kmap_atomic_pfn(unsigned long pfn)
+{
+        unsigned long vaddr;
+        int idx, type;
+
+        preempt_disable();
+        pagefault_disable();
+
+        type = kmap_atomic_idx_push();
+        idx = type + KM_TYPE_NR*smp_processor_id();
+        vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+        set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
+        flush_tlb_one(vaddr);
+
+        return (void*) vaddr;
+}
+
+void __init kmap_init(void)
+{
+        unsigned long kmap_vstart;
+
+        /* cache the first kmap pte */
+        kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
+        kmap_pte = virt_to_kpte(kmap_vstart);
+}