LXR linux/drivers/nvdimm/label.h

   1/*
   2 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of version 2 of the GNU General Public License as
   6 * published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful, but
   9 * WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 * General Public License for more details.
  12 */
  13#ifndef __LABEL_H__
  14#define __LABEL_H__
  15
  16#include <linux/ndctl.h>
  17#include <linux/sizes.h>
  18#include <linux/io.h>
  19
  20enum {
  21        NSINDEX_SIG_LEN = 16,
  22        NSINDEX_ALIGN = 256,
  23        NSINDEX_SEQ_MASK = 0x3,
  24        NSLABEL_UUID_LEN = 16,
  25        NSLABEL_NAME_LEN = 64,
  26        NSLABEL_FLAG_ROLABEL = 0x1,  /* read-only label */
  27        NSLABEL_FLAG_LOCAL = 0x2,    /* DIMM-local namespace */
  28        NSLABEL_FLAG_BTT = 0x4,      /* namespace contains a BTT */
  29        NSLABEL_FLAG_UPDATING = 0x8, /* label being updated */
  30        BTT_ALIGN = 4096,            /* all btt structures */
  31        BTTINFO_SIG_LEN = 16,
  32        BTTINFO_UUID_LEN = 16,
  33        BTTINFO_FLAG_ERROR = 0x1,    /* error state (read-only) */
  34        BTTINFO_MAJOR_VERSION = 1,
  35        ND_LABEL_MIN_SIZE = 512 * 129, /* see sizeof_namespace_index() */
  36        ND_LABEL_ID_SIZE = 50,
  37        ND_NSINDEX_INIT = 0x1,
  38};
  39
  40static const char NSINDEX_SIGNATURE[] = "NAMESPACE_INDEX\0";
  41
  42/**
  43 * struct nd_namespace_index - label set superblock
  44 * @sig: NAMESPACE_INDEX\0
  45 * @flags: placeholder
  46 * @seq: sequence number for this index
  47 * @myoff: offset of this index in label area
  48 * @mysize: size of this index struct
  49 * @otheroff: offset of other index
  50 * @labeloff: offset of first label slot
  51 * @nslot: total number of label slots
  52 * @major: label area major version
  53 * @minor: label area minor version
  54 * @checksum: fletcher64 of all fields
  55 * @free[0]: bitmap, nlabel bits
  56 *
  57 * The size of free[] is rounded up so the total struct size is a
  58 * multiple of NSINDEX_ALIGN bytes.  Any bits this allocates beyond
  59 * nlabel bits must be zero.
  60 */
  61struct nd_namespace_index {
  62        u8 sig[NSINDEX_SIG_LEN];
  63        __le32 flags;
  64        __le32 seq;
  65        __le64 myoff;
  66        __le64 mysize;
  67        __le64 otheroff;
  68        __le64 labeloff;
  69        __le32 nslot;
  70        __le16 major;
  71        __le16 minor;
  72        __le64 checksum;
  73        u8 free[0];
  74};
  75
  76/**
  77 * struct nd_namespace_label - namespace superblock
  78 * @uuid: UUID per RFC 4122
  79 * @name: optional name (NULL-terminated)
  80 * @flags: see NSLABEL_FLAG_*
  81 * @nlabel: num labels to describe this ns
  82 * @position: labels position in set
  83 * @isetcookie: interleave set cookie
  84 * @lbasize: LBA size in bytes or 0 for pmem
  85 * @dpa: DPA of NVM range on this DIMM
  86 * @rawsize: size of namespace
  87 * @slot: slot of this label in label area
  88 * @unused: must be zero
  89 */
  90struct nd_namespace_label {
  91        u8 uuid[NSLABEL_UUID_LEN];
  92        u8 name[NSLABEL_NAME_LEN];
  93        __le32 flags;
  94        __le16 nlabel;
  95        __le16 position;
  96        __le64 isetcookie;
  97        __le64 lbasize;
  98        __le64 dpa;
  99        __le64 rawsize;
 100        __le32 slot;
 101        __le32 unused;
 102};
 103
 104/**
 105 * struct nd_label_id - identifier string for dpa allocation
 106 * @id: "{blk|pmem}-<namespace uuid>"
 107 */
 108struct nd_label_id {
 109        char id[ND_LABEL_ID_SIZE];
 110};
 111
 112/*
 113 * If the 'best' index is invalid, so is the 'next' index.  Otherwise,
 114 * the next index is MOD(index+1, 2)
 115 */
 116static inline int nd_label_next_nsindex(int index)
 117{
 118        if (index < 0)
 119                return -1;
 120
 121        return (index + 1) % 2;
 122}
 123
 124struct nvdimm_drvdata;
 125int nd_label_validate(struct nvdimm_drvdata *ndd);
 126void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
 127                struct nd_namespace_index *src);
 128size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd);
 129int nd_label_active_count(struct nvdimm_drvdata *ndd);
 130struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n);
 131u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd);
 132bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot);
 133u32 nd_label_nfree(struct nvdimm_drvdata *ndd);
 134struct nd_region;
 135struct nd_namespace_pmem;
 136struct nd_namespace_blk;
 137int nd_pmem_namespace_label_update(struct nd_region *nd_region,
 138                struct nd_namespace_pmem *nspm, resource_size_t size);
 139int nd_blk_namespace_label_update(struct nd_region *nd_region,
 140                struct nd_namespace_blk *nsblk, resource_size_t size);
 141#endif /* __LABEL_H__ */
 142