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-rw-r--r--include/linux/pageblock-flags.h75
1 files changed, 75 insertions, 0 deletions
diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h
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+++ b/include/linux/pageblock-flags.h
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+/*
+ * 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>
+
+/* Macro to aid the definition of ranges of bits */
+#define PB_range(name, required_bits) \
+ name, name ## _end = (name + required_bits) - 1
+
+/* Bit indices that affect a whole block of pages */
+enum pageblock_bits {
+ PB_range(PB_migrate, 3), /* 3 bits required for migrate types */
+ 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;
+
+/* Declarations for getting and setting flags. See mm/page_alloc.c */
+unsigned long get_pageblock_flags_group(struct page *page,
+ int start_bitidx, int end_bitidx);
+void set_pageblock_flags_group(struct page *page, unsigned long flags,
+ int start_bitidx, int end_bitidx);
+
+#define get_pageblock_flags(page) \
+ get_pageblock_flags_group(page, 0, NR_PAGEBLOCK_BITS-1)
+#define set_pageblock_flags(page) \
+ set_pageblock_flags_group(page, 0, NR_PAGEBLOCK_BITS-1)
+
+#endif /* PAGEBLOCK_FLAGS_H */