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authorIngo Molnar <mingo@kernel.org>2012-04-14 13:18:27 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-14 13:19:04 +0200
commit6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch)
tree021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /arch/microblaze/mm/highmem.c
parent682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff)
parenta385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff)
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/microblaze/mm/highmem.c')
-rw-r--r--arch/microblaze/mm/highmem.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/arch/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
new file mode 100644
index 000000000000..7d78838e8bfa
--- /dev/null
+++ b/arch/microblaze/mm/highmem.c
@@ -0,0 +1,88 @@
+/*
+ * highmem.c: virtual kernel memory mappings for high memory
+ *
+ * PowerPC version, stolen from the i386 version.
+ *
+ * Used in CONFIG_HIGHMEM systems for memory pages which
+ * are not addressable by direct kernel virtual addresses.
+ *
+ * Copyright (C) 1999 Gerhard Wichert, Siemens AG
+ * Gerhard.Wichert@pdb.siemens.de
+ *
+ *
+ * Redesigned the x86 32-bit VM architecture to deal with
+ * up to 16 Terrabyte physical memory. With current x86 CPUs
+ * we now support up to 64 Gigabytes physical RAM.
+ *
+ * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
+ *
+ * Reworked for PowerPC by various contributors. Moved from
+ * highmem.h by Benjamin Herrenschmidt (c) 2009 IBM Corp.
+ */
+
+#include <linux/highmem.h>
+#include <linux/module.h>
+
+/*
+ * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
+ * gives a more generic (and caching) interface. But kmap_atomic can
+ * be used in IRQ contexts, so in some (very limited) cases we need
+ * it.
+ */
+#include <asm/tlbflush.h>
+
+void *kmap_atomic_prot(struct page *page, pgprot_t prot)
+{
+
+ unsigned long vaddr;
+ int idx, type;
+
+ /* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+
+
+ 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_at(&init_mm, vaddr, kmap_pte-idx, mk_pte(page, prot));
+ local_flush_tlb_page(NULL, vaddr);
+
+ return (void *) vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic_prot);
+
+void __kunmap_atomic(void *kvaddr)
+{
+ unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
+ int type;
+
+ if (vaddr < __fix_to_virt(FIX_KMAP_END)) {
+ pagefault_enable();
+ return;
+ }
+
+ type = kmap_atomic_idx();
+#ifdef CONFIG_DEBUG_HIGHMEM
+ {
+ unsigned int idx;
+
+ 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_page(NULL, vaddr);
+ }
+#endif
+ kmap_atomic_idx_pop();
+ pagefault_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);