xref: /openbmc/linux/drivers/nvdimm/label.h (revision 2bdd5238)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
4  */
5 #ifndef __LABEL_H__
6 #define __LABEL_H__
7 
8 #include <linux/ndctl.h>
9 #include <linux/sizes.h>
10 #include <linux/uuid.h>
11 #include <linux/io.h>
12 
13 enum {
14 	NSINDEX_SIG_LEN = 16,
15 	NSINDEX_ALIGN = 256,
16 	NSINDEX_SEQ_MASK = 0x3,
17 	NSLABEL_UUID_LEN = 16,
18 	NSLABEL_NAME_LEN = 64,
19 	NSLABEL_FLAG_ROLABEL = 0x1,  /* read-only label */
20 	NSLABEL_FLAG_LOCAL = 0x2,    /* DIMM-local namespace */
21 	NSLABEL_FLAG_BTT = 0x4,      /* namespace contains a BTT */
22 	NSLABEL_FLAG_UPDATING = 0x8, /* label being updated */
23 	BTT_ALIGN = 4096,            /* all btt structures */
24 	BTTINFO_SIG_LEN = 16,
25 	BTTINFO_UUID_LEN = 16,
26 	BTTINFO_FLAG_ERROR = 0x1,    /* error state (read-only) */
27 	BTTINFO_MAJOR_VERSION = 1,
28 	ND_LABEL_MIN_SIZE = 256 * 4, /* see sizeof_namespace_index() */
29 	ND_LABEL_ID_SIZE = 50,
30 	ND_NSINDEX_INIT = 0x1,
31 };
32 
33 /**
34  * struct nd_namespace_index - label set superblock
35  * @sig: NAMESPACE_INDEX\0
36  * @flags: placeholder
37  * @seq: sequence number for this index
38  * @myoff: offset of this index in label area
39  * @mysize: size of this index struct
40  * @otheroff: offset of other index
41  * @labeloff: offset of first label slot
42  * @nslot: total number of label slots
43  * @major: label area major version
44  * @minor: label area minor version
45  * @checksum: fletcher64 of all fields
46  * @free[0]: bitmap, nlabel bits
47  *
48  * The size of free[] is rounded up so the total struct size is a
49  * multiple of NSINDEX_ALIGN bytes.  Any bits this allocates beyond
50  * nlabel bits must be zero.
51  */
52 struct nd_namespace_index {
53 	u8 sig[NSINDEX_SIG_LEN];
54 	u8 flags[3];
55 	u8 labelsize;
56 	__le32 seq;
57 	__le64 myoff;
58 	__le64 mysize;
59 	__le64 otheroff;
60 	__le64 labeloff;
61 	__le32 nslot;
62 	__le16 major;
63 	__le16 minor;
64 	__le64 checksum;
65 	u8 free[];
66 };
67 
68 /**
69  * struct nd_namespace_label - namespace superblock
70  * @uuid: UUID per RFC 4122
71  * @name: optional name (NULL-terminated)
72  * @flags: see NSLABEL_FLAG_*
73  * @nlabel: num labels to describe this ns
74  * @position: labels position in set
75  * @isetcookie: interleave set cookie
76  * @lbasize: LBA size in bytes or 0 for pmem
77  * @dpa: DPA of NVM range on this DIMM
78  * @rawsize: size of namespace
79  * @slot: slot of this label in label area
80  * @unused: must be zero
81  */
82 struct nd_namespace_label {
83 	u8 uuid[NSLABEL_UUID_LEN];
84 	u8 name[NSLABEL_NAME_LEN];
85 	__le32 flags;
86 	__le16 nlabel;
87 	__le16 position;
88 	__le64 isetcookie;
89 	__le64 lbasize;
90 	__le64 dpa;
91 	__le64 rawsize;
92 	__le32 slot;
93 	/*
94 	 * Accessing fields past this point should be gated by a
95 	 * namespace_label_has() check.
96 	 */
97 	u8 align;
98 	u8 reserved[3];
99 	guid_t type_guid;
100 	guid_t abstraction_guid;
101 	u8 reserved2[88];
102 	__le64 checksum;
103 };
104 
105 #define NVDIMM_BTT_GUID "8aed63a2-29a2-4c66-8b12-f05d15d3922a"
106 #define NVDIMM_BTT2_GUID "18633bfc-1735-4217-8ac9-17239282d3f8"
107 #define NVDIMM_PFN_GUID "266400ba-fb9f-4677-bcb0-968f11d0d225"
108 #define NVDIMM_DAX_GUID "97a86d9c-3cdd-4eda-986f-5068b4f80088"
109 
110 /**
111  * struct nd_label_id - identifier string for dpa allocation
112  * @id: "{blk|pmem}-<namespace uuid>"
113  */
114 struct nd_label_id {
115 	char id[ND_LABEL_ID_SIZE];
116 };
117 
118 /*
119  * If the 'best' index is invalid, so is the 'next' index.  Otherwise,
120  * the next index is MOD(index+1, 2)
121  */
122 static inline int nd_label_next_nsindex(int index)
123 {
124 	if (index < 0)
125 		return -1;
126 
127 	return (index + 1) % 2;
128 }
129 
130 struct nvdimm_drvdata;
131 int nd_label_data_init(struct nvdimm_drvdata *ndd);
132 size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd);
133 int nd_label_active_count(struct nvdimm_drvdata *ndd);
134 struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n);
135 u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd);
136 bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot);
137 u32 nd_label_nfree(struct nvdimm_drvdata *ndd);
138 struct nd_region;
139 struct nd_namespace_pmem;
140 struct nd_namespace_blk;
141 int nd_pmem_namespace_label_update(struct nd_region *nd_region,
142 		struct nd_namespace_pmem *nspm, resource_size_t size);
143 int nd_blk_namespace_label_update(struct nd_region *nd_region,
144 		struct nd_namespace_blk *nsblk, resource_size_t size);
145 #endif /* __LABEL_H__ */
146