xref: /openbmc/linux/drivers/nvdimm/label.h (revision feac8c8b)
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/uuid.h>
19 #include <linux/io.h>
20 
21 enum {
22 	NSINDEX_SIG_LEN = 16,
23 	NSINDEX_ALIGN = 256,
24 	NSINDEX_SEQ_MASK = 0x3,
25 	NSLABEL_UUID_LEN = 16,
26 	NSLABEL_NAME_LEN = 64,
27 	NSLABEL_FLAG_ROLABEL = 0x1,  /* read-only label */
28 	NSLABEL_FLAG_LOCAL = 0x2,    /* DIMM-local namespace */
29 	NSLABEL_FLAG_BTT = 0x4,      /* namespace contains a BTT */
30 	NSLABEL_FLAG_UPDATING = 0x8, /* label being updated */
31 	BTT_ALIGN = 4096,            /* all btt structures */
32 	BTTINFO_SIG_LEN = 16,
33 	BTTINFO_UUID_LEN = 16,
34 	BTTINFO_FLAG_ERROR = 0x1,    /* error state (read-only) */
35 	BTTINFO_MAJOR_VERSION = 1,
36 	ND_LABEL_MIN_SIZE = 512 * 129, /* see sizeof_namespace_index() */
37 	ND_LABEL_ID_SIZE = 50,
38 	ND_NSINDEX_INIT = 0x1,
39 };
40 
41 static const char NSINDEX_SIGNATURE[] = "NAMESPACE_INDEX\0";
42 
43 /**
44  * struct nd_namespace_index - label set superblock
45  * @sig: NAMESPACE_INDEX\0
46  * @flags: placeholder
47  * @seq: sequence number for this index
48  * @myoff: offset of this index in label area
49  * @mysize: size of this index struct
50  * @otheroff: offset of other index
51  * @labeloff: offset of first label slot
52  * @nslot: total number of label slots
53  * @major: label area major version
54  * @minor: label area minor version
55  * @checksum: fletcher64 of all fields
56  * @free[0]: bitmap, nlabel bits
57  *
58  * The size of free[] is rounded up so the total struct size is a
59  * multiple of NSINDEX_ALIGN bytes.  Any bits this allocates beyond
60  * nlabel bits must be zero.
61  */
62 struct nd_namespace_index {
63 	u8 sig[NSINDEX_SIG_LEN];
64 	u8 flags[3];
65 	u8 labelsize;
66 	__le32 seq;
67 	__le64 myoff;
68 	__le64 mysize;
69 	__le64 otheroff;
70 	__le64 labeloff;
71 	__le32 nslot;
72 	__le16 major;
73 	__le16 minor;
74 	__le64 checksum;
75 	u8 free[0];
76 };
77 
78 /**
79  * struct nd_namespace_label - namespace superblock
80  * @uuid: UUID per RFC 4122
81  * @name: optional name (NULL-terminated)
82  * @flags: see NSLABEL_FLAG_*
83  * @nlabel: num labels to describe this ns
84  * @position: labels position in set
85  * @isetcookie: interleave set cookie
86  * @lbasize: LBA size in bytes or 0 for pmem
87  * @dpa: DPA of NVM range on this DIMM
88  * @rawsize: size of namespace
89  * @slot: slot of this label in label area
90  * @unused: must be zero
91  */
92 struct nd_namespace_label {
93 	u8 uuid[NSLABEL_UUID_LEN];
94 	u8 name[NSLABEL_NAME_LEN];
95 	__le32 flags;
96 	__le16 nlabel;
97 	__le16 position;
98 	__le64 isetcookie;
99 	__le64 lbasize;
100 	__le64 dpa;
101 	__le64 rawsize;
102 	__le32 slot;
103 	/*
104 	 * Accessing fields past this point should be gated by a
105 	 * namespace_label_has() check.
106 	 */
107 	u8 align;
108 	u8 reserved[3];
109 	guid_t type_guid;
110 	guid_t abstraction_guid;
111 	u8 reserved2[88];
112 	__le64 checksum;
113 };
114 
115 #define NVDIMM_BTT_GUID "8aed63a2-29a2-4c66-8b12-f05d15d3922a"
116 #define NVDIMM_BTT2_GUID "18633bfc-1735-4217-8ac9-17239282d3f8"
117 #define NVDIMM_PFN_GUID "266400ba-fb9f-4677-bcb0-968f11d0d225"
118 #define NVDIMM_DAX_GUID "97a86d9c-3cdd-4eda-986f-5068b4f80088"
119 
120 /**
121  * struct nd_label_id - identifier string for dpa allocation
122  * @id: "{blk|pmem}-<namespace uuid>"
123  */
124 struct nd_label_id {
125 	char id[ND_LABEL_ID_SIZE];
126 };
127 
128 /*
129  * If the 'best' index is invalid, so is the 'next' index.  Otherwise,
130  * the next index is MOD(index+1, 2)
131  */
132 static inline int nd_label_next_nsindex(int index)
133 {
134 	if (index < 0)
135 		return -1;
136 
137 	return (index + 1) % 2;
138 }
139 
140 struct nvdimm_drvdata;
141 int nd_label_validate(struct nvdimm_drvdata *ndd);
142 void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
143 		struct nd_namespace_index *src);
144 size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd);
145 int nd_label_active_count(struct nvdimm_drvdata *ndd);
146 struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n);
147 u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd);
148 bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot);
149 u32 nd_label_nfree(struct nvdimm_drvdata *ndd);
150 enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid);
151 struct nd_region;
152 struct nd_namespace_pmem;
153 struct nd_namespace_blk;
154 int nd_pmem_namespace_label_update(struct nd_region *nd_region,
155 		struct nd_namespace_pmem *nspm, resource_size_t size);
156 int nd_blk_namespace_label_update(struct nd_region *nd_region,
157 		struct nd_namespace_blk *nsblk, resource_size_t size);
158 #endif /* __LABEL_H__ */
159