1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
/*
* QEMU NVMe NGUID functions
*
* Copyright 2024 Google LLC
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that 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.
*/
#include "qemu/osdep.h"
#include "qapi/visitor.h"
#include "qemu/ctype.h"
#include "nvme.h"
#define NGUID_SEPARATOR '-'
#define NGUID_VALUE_AUTO "auto"
#define NGUID_FMT \
"%02hhx%02hhx%02hhx%02hhx" \
"%02hhx%02hhx%02hhx%02hhx" \
"%02hhx%02hhx%02hhx%02hhx" \
"%02hhx%02hhx%02hhx%02hhx"
#define NGUID_STR_LEN (2 * NGUID_LEN + 1)
bool nvme_nguid_is_null(const NvmeNGUID *nguid)
{
static NvmeNGUID null_nguid;
return memcmp(nguid, &null_nguid, sizeof(NvmeNGUID)) == 0;
}
static void nvme_nguid_generate(NvmeNGUID *out)
{
int i;
uint32_t x;
QEMU_BUILD_BUG_ON((NGUID_LEN % sizeof(x)) != 0);
for (i = 0; i < NGUID_LEN; i += sizeof(x)) {
x = g_random_int();
memcpy(&out->data[i], &x, sizeof(x));
}
}
/*
* The Linux Kernel typically prints the NGUID of an NVMe namespace using the
* same format as the UUID. For instance:
*
* $ cat /sys/class/block/nvme0n1/nguid
* e9accd3b-8390-4e13-167c-f0593437f57d
*
* When there is no UUID but there is NGUID the Kernel will print the NGUID as
* wwid and it won't use the UUID format:
*
* $ cat /sys/class/block/nvme0n1/wwid
* eui.e9accd3b83904e13167cf0593437f57d
*
* The NGUID has different fields compared to the UUID, so the grouping used in
* the UUID format has no relation with the 3 fields of the NGUID.
*
* This implementation won't expect a strict format as the UUID one and instead
* it will admit any string of hexadecimal digits. Byte groups could be created
* using the '-' separator. The number of bytes needs to be exactly 16 and the
* separator '-' has to be exactly in a byte boundary. The following are
* examples of accepted formats for the NGUID string:
*
* nguid="e9accd3b-8390-4e13-167c-f0593437f57d"
* nguid="e9accd3b83904e13167cf0593437f57d"
* nguid="FEDCBA9876543210-ABCDEF-0123456789"
*/
static bool nvme_nguid_is_valid(const char *str)
{
int i;
int digit_count = 0;
for (i = 0; i < strlen(str); i++) {
const char c = str[i];
if (qemu_isxdigit(c)) {
digit_count++;
continue;
}
if (c == NGUID_SEPARATOR) {
/*
* We need to make sure the separator is in a byte boundary, the
* string does not start with the separator and they are not back to
* back "--".
*/
if ((i > 0) && (str[i - 1] != NGUID_SEPARATOR) &&
(digit_count % 2) == 0) {
continue;
}
}
return false;
}
/*
* The string should have the correct byte length and not finish with the
* separator
*/
return (digit_count == (2 * NGUID_LEN)) && (str[i - 1] != NGUID_SEPARATOR);
}
static int nvme_nguid_parse(const char *str, NvmeNGUID *nguid)
{
uint8_t *id = &nguid->data[0];
int ret = 0;
int i;
const char *ptr = str;
if (!nvme_nguid_is_valid(str)) {
return -1;
}
for (i = 0; i < NGUID_LEN; i++) {
ret = sscanf(ptr, "%02hhx", &id[i]);
if (ret != 1) {
return -1;
}
ptr += 2;
if (*ptr == NGUID_SEPARATOR) {
ptr++;
}
}
return 0;
}
/*
* When converted back to string this implementation will use a raw hex number
* with no separators, for instance:
*
* "e9accd3b83904e13167cf0593437f57d"
*/
static void nvme_nguid_stringify(const NvmeNGUID *nguid, char *out)
{
const uint8_t *id = &nguid->data[0];
snprintf(out, NGUID_STR_LEN, NGUID_FMT,
id[0], id[1], id[2], id[3], id[4], id[5], id[6], id[7],
id[8], id[9], id[10], id[11], id[12], id[13], id[14], id[15]);
}
static void get_nguid(Object *obj, Visitor *v, const char *name, void *opaque,
Error **errp)
{
Property *prop = opaque;
NvmeNGUID *nguid = object_field_prop_ptr(obj, prop);
char buffer[NGUID_STR_LEN];
char *p = buffer;
nvme_nguid_stringify(nguid, buffer);
visit_type_str(v, name, &p, errp);
}
static void set_nguid(Object *obj, Visitor *v, const char *name, void *opaque,
Error **errp)
{
Property *prop = opaque;
NvmeNGUID *nguid = object_field_prop_ptr(obj, prop);
char *str;
if (!visit_type_str(v, name, &str, errp)) {
return;
}
if (!strcmp(str, NGUID_VALUE_AUTO)) {
nvme_nguid_generate(nguid);
} else if (nvme_nguid_parse(str, nguid) < 0) {
error_set_from_qdev_prop_error(errp, EINVAL, obj, name, str);
}
g_free(str);
}
const PropertyInfo qdev_prop_nguid = {
.name = "str",
.description =
"NGUID or \"" NGUID_VALUE_AUTO "\" for random value",
.get = get_nguid,
.set = set_nguid,
};
|
