[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/include/asm-generic/tlb.h b/ap/os/linux/linux-3.4.x/include/asm-generic/tlb.h
new file mode 100644
index 0000000..979ed15
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/include/asm-generic/tlb.h
@@ -0,0 +1,187 @@
+/* include/asm-generic/tlb.h
+ *
+ * Generic TLB shootdown code
+ *
+ * Copyright 2001 Red Hat, Inc.
+ * Based on code from mm/memory.c Copyright Linus Torvalds and others.
+ *
+ * Copyright 2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#ifndef _ASM_GENERIC__TLB_H
+#define _ASM_GENERIC__TLB_H
+
+#include <linux/swap.h>
+#include <asm/pgalloc.h>
+#include <asm/tlbflush.h>
+
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+/*
+ * Semi RCU freeing of the page directories.
+ *
+ * This is needed by some architectures to implement software pagetable walkers.
+ *
+ * gup_fast() and other software pagetable walkers do a lockless page-table
+ * walk and therefore needs some synchronization with the freeing of the page
+ * directories. The chosen means to accomplish that is by disabling IRQs over
+ * the walk.
+ *
+ * Architectures that use IPIs to flush TLBs will then automagically DTRT,
+ * since we unlink the page, flush TLBs, free the page. Since the disabling of
+ * IRQs delays the completion of the TLB flush we can never observe an already
+ * freed page.
+ *
+ * Architectures that do not have this (PPC) need to delay the freeing by some
+ * other means, this is that means.
+ *
+ * What we do is batch the freed directory pages (tables) and RCU free them.
+ * We use the sched RCU variant, as that guarantees that IRQ/preempt disabling
+ * holds off grace periods.
+ *
+ * However, in order to batch these pages we need to allocate storage, this
+ * allocation is deep inside the MM code and can thus easily fail on memory
+ * pressure. To guarantee progress we fall back to single table freeing, see
+ * the implementation of tlb_remove_table_one().
+ *
+ */
+struct mmu_table_batch {
+ struct rcu_head rcu;
+ unsigned int nr;
+ void *tables[0];
+};
+
+#define MAX_TABLE_BATCH \
+ ((PAGE_SIZE - sizeof(struct mmu_table_batch)) / sizeof(void *))
+
+extern void tlb_table_flush(struct mmu_gather *tlb);
+extern void tlb_remove_table(struct mmu_gather *tlb, void *table);
+
+#endif
+
+/*
+ * If we can't allocate a page to make a big batch of page pointers
+ * to work on, then just handle a few from the on-stack structure.
+ */
+#define MMU_GATHER_BUNDLE 8
+
+struct mmu_gather_batch {
+ struct mmu_gather_batch *next;
+ unsigned int nr;
+ unsigned int max;
+ struct page *pages[0];
+};
+
+#define MAX_GATHER_BATCH \
+ ((PAGE_SIZE - sizeof(struct mmu_gather_batch)) / sizeof(void *))
+
+/*
+ * Limit the maximum number of mmu_gather batches to reduce a risk of soft
+ * lockups for non-preemptible kernels on huge machines when a lot of memory
+ * is zapped during unmapping.
+ * 10K pages freed at once should be safe even without a preemption point.
+ */
+#define MAX_GATHER_BATCH_COUNT (10000UL/MAX_GATHER_BATCH)
+
+/* struct mmu_gather is an opaque type used by the mm code for passing around
+ * any data needed by arch specific code for tlb_remove_page.
+ */
+struct mmu_gather {
+ struct mm_struct *mm;
+#ifdef CONFIG_HAVE_RCU_TABLE_FREE
+ struct mmu_table_batch *batch;
+#endif
+ unsigned int need_flush : 1, /* Did free PTEs */
+ fast_mode : 1; /* No batching */
+
+ unsigned int fullmm;
+
+ struct mmu_gather_batch *active;
+ struct mmu_gather_batch local;
+ struct page *__pages[MMU_GATHER_BUNDLE];
+ unsigned int batch_count;
+};
+
+#define HAVE_GENERIC_MMU_GATHER
+
+static inline int tlb_fast_mode(struct mmu_gather *tlb)
+{
+#ifdef CONFIG_SMP
+ return tlb->fast_mode;
+#else
+ /*
+ * For UP we don't need to worry about TLB flush
+ * and page free order so much..
+ */
+ return 1;
+#endif
+}
+
+void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, bool fullmm);
+void tlb_flush_mmu(struct mmu_gather *tlb);
+void tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end);
+int __tlb_remove_page(struct mmu_gather *tlb, struct page *page);
+
+/* tlb_remove_page
+ * Similar to __tlb_remove_page but will call tlb_flush_mmu() itself when
+ * required.
+ */
+static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
+{
+ if (!__tlb_remove_page(tlb, page))
+ tlb_flush_mmu(tlb);
+}
+
+/**
+ * tlb_remove_tlb_entry - remember a pte unmapping for later tlb invalidation.
+ *
+ * Record the fact that pte's were really umapped in ->need_flush, so we can
+ * later optimise away the tlb invalidate. This helps when userspace is
+ * unmapping already-unmapped pages, which happens quite a lot.
+ */
+#define tlb_remove_tlb_entry(tlb, ptep, address) \
+ do { \
+ tlb->need_flush = 1; \
+ __tlb_remove_tlb_entry(tlb, ptep, address); \
+ } while (0)
+
+/**
+ * tlb_remove_pmd_tlb_entry - remember a pmd mapping for later tlb invalidation
+ * This is a nop so far, because only x86 needs it.
+ */
+#ifndef __tlb_remove_pmd_tlb_entry
+#define __tlb_remove_pmd_tlb_entry(tlb, pmdp, address) do {} while (0)
+#endif
+
+#define tlb_remove_pmd_tlb_entry(tlb, pmdp, address) \
+ do { \
+ tlb->need_flush = 1; \
+ __tlb_remove_pmd_tlb_entry(tlb, pmdp, address); \
+ } while (0)
+
+#define pte_free_tlb(tlb, ptep, address) \
+ do { \
+ tlb->need_flush = 1; \
+ __pte_free_tlb(tlb, ptep, address); \
+ } while (0)
+
+#ifndef __ARCH_HAS_4LEVEL_HACK
+#define pud_free_tlb(tlb, pudp, address) \
+ do { \
+ tlb->need_flush = 1; \
+ __pud_free_tlb(tlb, pudp, address); \
+ } while (0)
+#endif
+
+#define pmd_free_tlb(tlb, pmdp, address) \
+ do { \
+ tlb->need_flush = 1; \
+ __pmd_free_tlb(tlb, pmdp, address); \
+ } while (0)
+
+#define tlb_migrate_finish(mm) do {} while (0)
+
+#endif /* _ASM_GENERIC__TLB_H */