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+/*
+ * firmware_memmap.c: Read /sys/firmware/memmap
+ *
+ * Created by: Bernhard Walle (bernhard.walle@gmx.de)
+ * Copyright (C) SUSE LINUX Products GmbH, 2008. All rights reserved
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#ifndef FIRMWARE_MEMMAP_H
+#define FIRMWARE_MEMMAP_H
+
+#include "kexec.h"
+
+/**
+ * Reads the /sys/firmware/memmap interface, documented in
+ * Documentation/ABI/testing/sysfs-firmware-memmap (kernel tree).
+ *
+ * The difference between /proc/iomem and /sys/firmware/memmap is that
+ * /sys/firmware/memmap provides the raw memory map, provided by the
+ * firmware of the system. That memory map should be passed to a kexec'd
+ * kernel because the behaviour should be the same as a normal booted kernel,
+ * so any limitation (e.g. by the user providing the mem command line option)
+ * should not be passed to the kexec'd kernel.
+ *
+ * The parsing of the code is independent of the architecture. However, the
+ * actual architecture-specific code might postprocess the code a bit, like
+ * x86 does.
+ */
+
+/**
+ * Compares two memory ranges according to their start address. This function
+ * can be used with qsort() as @c compar function.
+ *
+ * @param[in] first a pointer to the first memory range
+ * @param[in] second a pointer to the second memory range
+ * @return 0 if @p first and @p second have the same start address,
+ * a value less then 0 if the start address of @p first is less than
+ * the start address of @p second, and a value greater than 0 if
+ * the opposite is in case.
+ */
+int compare_ranges(const void *first, const void *second);
+
+/**
+ * Checks if the kernel provides the /sys/firmware/memmap interface.
+ * It makes sense to use that function in advance before calling
+ * get_firmware_memmap_ranges() because the latter function prints an error
+ * if it cannot open the directory. If have_sys_firmware_memmap() returns
+ * false, then one can use the old /proc/iomem interface (for older kernels).
+ */
+int have_sys_firmware_memmap(void);
+
+/**
+ * Parses the /sys/firmware/memmap memory map.
+ *
+ * @param[out] range a pointer to an array of type struct memory_range with
+ * at least *range entries
+ * @param[in,out] ranges a pointer to an integer that holds the number of
+ * entries which range contains (at least). After successful
+ * return, the number of actual entries will be written.
+ * @return 0 on success, -1 on failure.
+ */
+int get_firmware_memmap_ranges(struct memory_range *range, size_t *ranges);
+
+
+#endif /* FIRMWARE_MEMMAP_H */