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-rw-r--r--include/linux/pageblock-flags.h101
1 files changed, 101 insertions, 0 deletions
diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
new file mode 100644
index 000000000..2baeee12f
--- /dev/null
+++ b/include/linux/pageblock-flags.h
@@ -0,0 +1,101 @@
+/*
+ * Macros for manipulating and testing flags related to a
+ * pageblock_nr_pages number of pages.
+ *
+ * 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 version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) IBM Corporation, 2006
+ *
+ * Original author, Mel Gorman
+ * Major cleanups and reduction of bit operations, Andy Whitcroft
+ */
+#ifndef PAGEBLOCK_FLAGS_H
+#define PAGEBLOCK_FLAGS_H
+
+#include <linux/types.h>
+
+/* Bit indices that affect a whole block of pages */
+enum pageblock_bits {
+ PB_migrate,
+ PB_migrate_end = PB_migrate + 3 - 1,
+ /* 3 bits required for migrate types */
+ PB_migrate_skip,/* If set the block is skipped by compaction */
+
+ /*
+ * Assume the bits will always align on a word. If this assumption
+ * changes then get/set pageblock needs updating.
+ */
+ NR_PAGEBLOCK_BITS
+};
+
+#ifdef CONFIG_HUGETLB_PAGE
+
+#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
+
+/* Huge page sizes are variable */
+extern int pageblock_order;
+
+#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
+
+/* Huge pages are a constant size */
+#define pageblock_order HUGETLB_PAGE_ORDER
+
+#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
+
+#else /* CONFIG_HUGETLB_PAGE */
+
+/* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
+#define pageblock_order (MAX_ORDER-1)
+
+#endif /* CONFIG_HUGETLB_PAGE */
+
+#define pageblock_nr_pages (1UL << pageblock_order)
+
+/* Forward declaration */
+struct page;
+
+unsigned long get_pfnblock_flags_mask(struct page *page,
+ unsigned long pfn,
+ unsigned long end_bitidx,
+ unsigned long mask);
+
+void set_pfnblock_flags_mask(struct page *page,
+ unsigned long flags,
+ unsigned long pfn,
+ unsigned long end_bitidx,
+ unsigned long mask);
+
+/* Declarations for getting and setting flags. See mm/page_alloc.c */
+#define get_pageblock_flags_group(page, start_bitidx, end_bitidx) \
+ get_pfnblock_flags_mask(page, page_to_pfn(page), \
+ end_bitidx, \
+ (1 << (end_bitidx - start_bitidx + 1)) - 1)
+#define set_pageblock_flags_group(page, flags, start_bitidx, end_bitidx) \
+ set_pfnblock_flags_mask(page, flags, page_to_pfn(page), \
+ end_bitidx, \
+ (1 << (end_bitidx - start_bitidx + 1)) - 1)
+
+#ifdef CONFIG_COMPACTION
+#define get_pageblock_skip(page) \
+ get_pageblock_flags_group(page, PB_migrate_skip, \
+ PB_migrate_skip)
+#define clear_pageblock_skip(page) \
+ set_pageblock_flags_group(page, 0, PB_migrate_skip, \
+ PB_migrate_skip)
+#define set_pageblock_skip(page) \
+ set_pageblock_flags_group(page, 1, PB_migrate_skip, \
+ PB_migrate_skip)
+#endif /* CONFIG_COMPACTION */
+
+#endif /* PAGEBLOCK_FLAGS_H */