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
  20 enum {
  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
  40 static 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  */
  61 struct 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  */
  90 struct 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  */
 108 struct 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  */
 116 static inline int nd_label_next_nsindex(int index)
 117 {
 118         if (index < 0)
 119                 return -1;
 120
 121         return (index + 1) % 2;
 122 }
 123
 124 struct nvdimm_drvdata;
 125 int nd_label_validate(struct nvdimm_drvdata *ndd);
 126 void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
 127                 struct nd_namespace_index *src);
 128 size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd);
 129 int nd_label_active_count(struct nvdimm_drvdata *ndd);
 130 struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n);
 131 u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd);
 132 bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot);
 133 u32 nd_label_nfree(struct nvdimm_drvdata *ndd);
 134 struct nd_region;
 135 struct nd_namespace_pmem;
 136 struct nd_namespace_blk;
 137 int nd_pmem_namespace_label_update(struct nd_region *nd_region,
 138                 struct nd_namespace_pmem *nspm, resource_size_t size);
 139 int nd_blk_namespace_label_update(struct nd_region *nd_region,
 140                 struct nd_namespace_blk *nsblk, resource_size_t size);
 141 #endif /* __LABEL_H__ */