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Diffstat (limited to '')
-rw-r--r-- | kexec/firmware_memmap.h | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/kexec/firmware_memmap.h b/kexec/firmware_memmap.h new file mode 100644 index 0000000..eac0ddb --- /dev/null +++ b/kexec/firmware_memmap.h @@ -0,0 +1,76 @@ +/* + * 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 */ |