kernel/drivers/nvdimm/pfn.h

60 lines
1.9 KiB
C

/*
* Copyright (c) 2014-2015, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*/
#ifndef __NVDIMM_PFN_H
#define __NVDIMM_PFN_H
#include <linux/types.h>
#include <linux/mmzone.h>
#define PFN_SIG_LEN 16
#define PFN_SIG "NVDIMM_PFN_INFO\0"
#define DAX_SIG "NVDIMM_DAX_INFO\0"
struct nd_pfn_sb {
u8 signature[PFN_SIG_LEN];
u8 uuid[16];
u8 parent_uuid[16];
__le32 flags;
__le16 version_major;
__le16 version_minor;
__le64 dataoff; /* relative to namespace_base + start_pad */
__le64 npfns;
__le32 mode;
/* minor-version-1 additions for section alignment */
/**
* @start_pad: Deprecated attribute to pad start-misaligned namespaces
*
* start_pad is deprecated because the original definition did
* not comprehend that dataoff is relative to the base address
* of the namespace not the start_pad adjusted base. The result
* is that the dax path is broken, but the block-I/O path is
* not. The kernel will no longer create namespaces using start
* padding, but it still supports block-I/O for legacy
* configurations mainly to allow a backup, reconfigure the
* namespace, and restore flow to repair dax operation.
*/
__le32 start_pad;
__le32 end_trunc;
/* minor-version-2 record the base alignment of the mapping */
__le32 align;
/* minor-version-3 guarantee the padding and flags are zero */
/* minor-version-4 record the page size and struct page size */
__le32 page_size;
__le16 page_struct_size;
u8 padding[3994];
__le64 checksum;
};
#endif /* __NVDIMM_PFN_H */