projects/linux·blob v4.7 · refs

254 lines · 4.9 KiB

1/*
2 * Parse command line, get partition information
3 *
4 * Written by Cai Zhiyong <[email protected]>
5 *
6 */
7#include <linux/export.h>
8#include <linux/cmdline-parser.h>
9
10static int parse_subpart(struct cmdline_subpart **subpart, char *partdef)
11{
12 int ret = 0;
13 struct cmdline_subpart *new_subpart;
14
15 *subpart = NULL;
16
17 new_subpart = kzalloc(sizeof(struct cmdline_subpart), GFP_KERNEL);
18 if (!new_subpart)
19 return -ENOMEM;
20
21 if (*partdef == '-') {
22 new_subpart->size = (sector_t)(~0ULL);
23 partdef++;
24 } else {
25 new_subpart->size = (sector_t)memparse(partdef, &partdef);
26 if (new_subpart->size < (sector_t)PAGE_SIZE) {
27 pr_warn("cmdline partition size is invalid.");
28 ret = -EINVAL;
29 goto fail;
30 }
31 }
32
33 if (*partdef == '@') {
34 partdef++;
35 new_subpart->from = (sector_t)memparse(partdef, &partdef);
36 } else {
37 new_subpart->from = (sector_t)(~0ULL);
38 }
39
40 if (*partdef == '(') {
41 int length;
42 char *next = strchr(++partdef, ')');
43
44 if (!next) {
45 pr_warn("cmdline partition format is invalid.");
46 ret = -EINVAL;
47 goto fail;
48 }
49
50 length = min_t(int, next - partdef,
51 sizeof(new_subpart->name) - 1);
52 strncpy(new_subpart->name, partdef, length);
53 new_subpart->name[length] = '\0';
54
55 partdef = ++next;
56 } else
57 new_subpart->name[0] = '\0';
58
59 new_subpart->flags = 0;
60
61 if (!strncmp(partdef, "ro", 2)) {
62 new_subpart->flags |= PF_RDONLY;
63 partdef += 2;
64 }
65
66 if (!strncmp(partdef, "lk", 2)) {
67 new_subpart->flags |= PF_POWERUP_LOCK;
68 partdef += 2;
69 }
70
71 *subpart = new_subpart;
72 return 0;
73fail:
74 kfree(new_subpart);
75 return ret;
76}
77
78static void free_subpart(struct cmdline_parts *parts)
79{
80 struct cmdline_subpart *subpart;
81
82 while (parts->subpart) {
83 subpart = parts->subpart;
84 parts->subpart = subpart->next_subpart;
85 kfree(subpart);
86 }
87}
88
89static int parse_parts(struct cmdline_parts **parts, const char *bdevdef)
90{
91 int ret = -EINVAL;
92 char *next;
93 int length;
94 struct cmdline_subpart **next_subpart;
95 struct cmdline_parts *newparts;
96 char buf[BDEVNAME_SIZE + 32 + 4];
97
98 *parts = NULL;
99
100 newparts = kzalloc(sizeof(struct cmdline_parts), GFP_KERNEL);
101 if (!newparts)
102 return -ENOMEM;
103
104 next = strchr(bdevdef, ':');
105 if (!next) {
106 pr_warn("cmdline partition has no block device.");
107 goto fail;
108 }
109
110 length = min_t(int, next - bdevdef, sizeof(newparts->name) - 1);
111 strncpy(newparts->name, bdevdef, length);
112 newparts->name[length] = '\0';
113 newparts->nr_subparts = 0;
114
115 next_subpart = &newparts->subpart;
116
117 while (next && *(++next)) {
118 bdevdef = next;
119 next = strchr(bdevdef, ',');
120
121 length = (!next) ? (sizeof(buf) - 1) :
122 min_t(int, next - bdevdef, sizeof(buf) - 1);
123
124 strncpy(buf, bdevdef, length);
125 buf[length] = '\0';
126
127 ret = parse_subpart(next_subpart, buf);
128 if (ret)
129 goto fail;
130
131 newparts->nr_subparts++;
132 next_subpart = &(*next_subpart)->next_subpart;
133 }
134
135 if (!newparts->subpart) {
136 pr_warn("cmdline partition has no valid partition.");
137 ret = -EINVAL;
138 goto fail;
139 }
140
141 *parts = newparts;
142
143 return 0;
144fail:
145 free_subpart(newparts);
146 kfree(newparts);
147 return ret;
148}
149
150void cmdline_parts_free(struct cmdline_parts **parts)
151{
152 struct cmdline_parts *next_parts;
153
154 while (*parts) {
155 next_parts = (*parts)->next_parts;
156 free_subpart(*parts);
157 kfree(*parts);
158 *parts = next_parts;
159 }
160}
161EXPORT_SYMBOL(cmdline_parts_free);
162
163int cmdline_parts_parse(struct cmdline_parts **parts, const char *cmdline)
164{
165 int ret;
166 char *buf;
167 char *pbuf;
168 char *next;
169 struct cmdline_parts **next_parts;
170
171 *parts = NULL;
172
173 next = pbuf = buf = kstrdup(cmdline, GFP_KERNEL);
174 if (!buf)
175 return -ENOMEM;
176
177 next_parts = parts;
178
179 while (next && *pbuf) {
180 next = strchr(pbuf, ';');
181 if (next)
182 *next = '\0';
183
184 ret = parse_parts(next_parts, pbuf);
185 if (ret)
186 goto fail;
187
188 if (next)
189 pbuf = ++next;
190
191 next_parts = &(*next_parts)->next_parts;
192 }
193
194 if (!*parts) {
195 pr_warn("cmdline partition has no valid partition.");
196 ret = -EINVAL;
197 goto fail;
198 }
199
200 ret = 0;
201done:
202 kfree(buf);
203 return ret;
204
205fail:
206 cmdline_parts_free(parts);
207 goto done;
208}
209EXPORT_SYMBOL(cmdline_parts_parse);
210
211struct cmdline_parts *cmdline_parts_find(struct cmdline_parts *parts,
212 const char *bdev)
213{
214 while (parts && strncmp(bdev, parts->name, sizeof(parts->name)))
215 parts = parts->next_parts;
216 return parts;
217}
218EXPORT_SYMBOL(cmdline_parts_find);
219
220/*
221 * add_part()
222 * 0 success.
223 * 1 can not add so many partitions.
224 */
225int cmdline_parts_set(struct cmdline_parts *parts, sector_t disk_size,
226 int slot,
227 int (*add_part)(int, struct cmdline_subpart *, void *),
228 void *param)
229{
230 sector_t from = 0;
231 struct cmdline_subpart *subpart;
232
233 for (subpart = parts->subpart; subpart;
234 subpart = subpart->next_subpart, slot++) {
235 if (subpart->from == (sector_t)(~0ULL))
236 subpart->from = from;
237 else
238 from = subpart->from;
239
240 if (from >= disk_size)
241 break;
242
243 if (subpart->size > (disk_size - from))
244 subpart->size = disk_size - from;
245
246 from += subpart->size;
247
248 if (add_part(slot, subpart, param))
249 break;
250 }
251
252 return slot;
253}
254EXPORT_SYMBOL(cmdline_parts_set);