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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Thomas Gleixner97894cd2005-11-07 11:15:26 +00002 * $Id: cmdlinepart.c,v 1.19 2005/11/07 11:14:19 gleixner Exp $
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
4 * Read flash partition table from command line
5 *
6 * Copyright 2002 SYSGO Real-Time Solutions GmbH
7 *
8 * The format for the command line is as follows:
Thomas Gleixner97894cd2005-11-07 11:15:26 +00009 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 * mtdparts=<mtddef>[;<mtddef]
11 * <mtddef> := <mtd-id>:<partdef>[,<partdef>]
Justin Treone619a752008-01-30 10:25:49 -080012 * <partdef> := <size>[@offset][<name>][ro][lk]
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * <mtd-id> := unique name used in mapping driver/device (mtd->name)
14 * <size> := standard linux memsize OR "-" to denote all remaining space
15 * <name> := '(' NAME ')'
Thomas Gleixner97894cd2005-11-07 11:15:26 +000016 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 * Examples:
Thomas Gleixner97894cd2005-11-07 11:15:26 +000018 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070019 * 1 NOR Flash, with 1 single writable partition:
20 * edb7312-nor:-
Thomas Gleixner97894cd2005-11-07 11:15:26 +000021 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 * 1 NOR Flash with 2 partitions, 1 NAND with one
23 * edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)
24 */
25
26#include <linux/kernel.h>
27#include <linux/slab.h>
28
29#include <linux/mtd/mtd.h>
30#include <linux/mtd/partitions.h>
31#include <linux/bootmem.h>
32
33/* error message prefix */
34#define ERRP "mtd: "
35
36/* debug macro */
37#if 0
38#define dbg(x) do { printk("DEBUG-CMDLINE-PART: "); printk x; } while(0)
39#else
40#define dbg(x)
41#endif
42
43
44/* special size referring to all the remaining space in a partition */
Atsushi Nemotob175d032006-03-31 02:29:46 -080045#define SIZE_REMAINING UINT_MAX
46#define OFFSET_CONTINUOUS UINT_MAX
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48struct cmdline_mtd_partition {
49 struct cmdline_mtd_partition *next;
50 char *mtd_id;
51 int num_parts;
52 struct mtd_partition *parts;
53};
54
55/* mtdpart_setup() parses into here */
56static struct cmdline_mtd_partition *partitions;
57
58/* the command line passed to mtdpart_setupd() */
59static char *cmdline;
60static int cmdline_parsed = 0;
61
62/*
63 * Parse one partition definition for an MTD. Since there can be many
Thomas Gleixner97894cd2005-11-07 11:15:26 +000064 * comma separated partition definitions, this function calls itself
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 * recursively until no more partition definitions are found. Nice side
66 * effect: the memory to keep the mtd_partition structs and the names
67 * is allocated upon the last definition being found. At that point the
68 * syntax has been verified ok.
69 */
Thomas Gleixner97894cd2005-11-07 11:15:26 +000070static struct mtd_partition * newpart(char *s,
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 char **retptr,
72 int *num_parts,
Thomas Gleixner97894cd2005-11-07 11:15:26 +000073 int this_part,
74 unsigned char **extra_mem_ptr,
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 int extra_mem_size)
76{
77 struct mtd_partition *parts;
78 unsigned long size;
Atsushi Nemotob175d032006-03-31 02:29:46 -080079 unsigned long offset = OFFSET_CONTINUOUS;
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 char *name;
81 int name_len;
82 unsigned char *extra_mem;
83 char delim;
84 unsigned int mask_flags;
85
86 /* fetch the partition size */
87 if (*s == '-')
88 { /* assign all remaining space to this partition */
89 size = SIZE_REMAINING;
90 s++;
91 }
92 else
93 {
94 size = memparse(s, &s);
95 if (size < PAGE_SIZE)
96 {
97 printk(KERN_ERR ERRP "partition size too small (%lx)\n", size);
98 return NULL;
99 }
100 }
101
102 /* fetch partition name and flags */
103 mask_flags = 0; /* this is going to be a regular partition */
104 delim = 0;
105 /* check for offset */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000106 if (*s == '@')
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 {
108 s++;
109 offset = memparse(s, &s);
110 }
111 /* now look for name */
112 if (*s == '(')
113 {
114 delim = ')';
115 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000116
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 if (delim)
118 {
119 char *p;
120
121 name = ++s;
Adrian Bunked262c42008-04-14 17:20:04 +0300122 p = strchr(name, delim);
123 if (!p)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 {
125 printk(KERN_ERR ERRP "no closing %c found in partition name\n", delim);
126 return NULL;
127 }
128 name_len = p - name;
129 s = p + 1;
130 }
131 else
132 {
133 name = NULL;
134 name_len = 13; /* Partition_000 */
135 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000136
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 /* record name length for memory allocation later */
138 extra_mem_size += name_len + 1;
139
140 /* test for options */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000141 if (strncmp(s, "ro", 2) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 {
143 mask_flags |= MTD_WRITEABLE;
144 s += 2;
145 }
146
Justin Treone619a752008-01-30 10:25:49 -0800147 /* if lk is found do NOT unlock the MTD partition*/
148 if (strncmp(s, "lk", 2) == 0)
149 {
150 mask_flags |= MTD_POWERUP_LOCK;
151 s += 2;
152 }
153
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 /* test if more partitions are following */
155 if (*s == ',')
156 {
157 if (size == SIZE_REMAINING)
158 {
159 printk(KERN_ERR ERRP "no partitions allowed after a fill-up partition\n");
160 return NULL;
161 }
162 /* more partitions follow, parse them */
Adrian Bunked262c42008-04-14 17:20:04 +0300163 parts = newpart(s + 1, &s, num_parts, this_part + 1,
164 &extra_mem, extra_mem_size);
165 if (!parts)
166 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 }
168 else
169 { /* this is the last partition: allocate space for all */
170 int alloc_size;
171
172 *num_parts = this_part + 1;
173 alloc_size = *num_parts * sizeof(struct mtd_partition) +
174 extra_mem_size;
Burman Yan95b93a02006-11-15 21:10:29 +0200175 parts = kzalloc(alloc_size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 if (!parts)
177 {
178 printk(KERN_ERR ERRP "out of memory\n");
179 return NULL;
180 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 extra_mem = (unsigned char *)(parts + *num_parts);
182 }
183 /* enter this partition (offset will be calculated later if it is zero at this point) */
184 parts[this_part].size = size;
185 parts[this_part].offset = offset;
186 parts[this_part].mask_flags = mask_flags;
187 if (name)
188 {
189 strlcpy(extra_mem, name, name_len + 1);
190 }
191 else
192 {
193 sprintf(extra_mem, "Partition_%03d", this_part);
194 }
195 parts[this_part].name = extra_mem;
196 extra_mem += name_len + 1;
197
198 dbg(("partition %d: name <%s>, offset %x, size %x, mask flags %x\n",
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000199 this_part,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 parts[this_part].name,
201 parts[this_part].offset,
202 parts[this_part].size,
203 parts[this_part].mask_flags));
204
205 /* return (updated) pointer to extra_mem memory */
206 if (extra_mem_ptr)
207 *extra_mem_ptr = extra_mem;
208
209 /* return (updated) pointer command line string */
210 *retptr = s;
211
212 /* return partition table */
213 return parts;
214}
215
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000216/*
217 * Parse the command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 */
219static int mtdpart_setup_real(char *s)
220{
221 cmdline_parsed = 1;
222
223 for( ; s != NULL; )
224 {
225 struct cmdline_mtd_partition *this_mtd;
226 struct mtd_partition *parts;
227 int mtd_id_len;
228 int num_parts;
229 char *p, *mtd_id;
230
231 mtd_id = s;
232 /* fetch <mtd-id> */
233 if (!(p = strchr(s, ':')))
234 {
235 printk(KERN_ERR ERRP "no mtd-id\n");
236 return 0;
237 }
238 mtd_id_len = p - mtd_id;
239
240 dbg(("parsing <%s>\n", p+1));
241
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000242 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 * parse one mtd. have it reserve memory for the
244 * struct cmdline_mtd_partition and the mtd-id string.
245 */
246 parts = newpart(p + 1, /* cmdline */
247 &s, /* out: updated cmdline ptr */
248 &num_parts, /* out: number of parts */
249 0, /* first partition */
250 (unsigned char**)&this_mtd, /* out: extra mem */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000251 mtd_id_len + 1 + sizeof(*this_mtd) +
Joern Engelbe76c5f2005-06-07 16:04:29 +0100252 sizeof(void*)-1 /*alignment*/);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 if(!parts)
254 {
255 /*
256 * An error occurred. We're either:
257 * a) out of memory, or
258 * b) in the middle of the partition spec
259 * Either way, this mtd is hosed and we're
260 * unlikely to succeed in parsing any more
261 */
262 return 0;
263 }
264
Joern Engelbe76c5f2005-06-07 16:04:29 +0100265 /* align this_mtd */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000266 this_mtd = (struct cmdline_mtd_partition *)
Joern Engelbe76c5f2005-06-07 16:04:29 +0100267 ALIGN((unsigned long)this_mtd, sizeof(void*));
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000268 /* enter results */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 this_mtd->parts = parts;
270 this_mtd->num_parts = num_parts;
271 this_mtd->mtd_id = (char*)(this_mtd + 1);
272 strlcpy(this_mtd->mtd_id, mtd_id, mtd_id_len + 1);
273
274 /* link into chain */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000275 this_mtd->next = partitions;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 partitions = this_mtd;
277
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000278 dbg(("mtdid=<%s> num_parts=<%d>\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 this_mtd->mtd_id, this_mtd->num_parts));
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000280
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281
282 /* EOS - we're done */
283 if (*s == 0)
284 break;
285
286 /* does another spec follow? */
287 if (*s != ';')
288 {
289 printk(KERN_ERR ERRP "bad character after partition (%c)\n", *s);
290 return 0;
291 }
292 s++;
293 }
294 return 1;
295}
296
297/*
298 * Main function to be called from the MTD mapping driver/device to
299 * obtain the partitioning information. At this point the command line
300 * arguments will actually be parsed and turned to struct mtd_partition
301 * information. It returns partitions for the requested mtd device, or
302 * the first one in the chain if a NULL mtd_id is passed in.
303 */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000304static int parse_cmdline_partitions(struct mtd_info *master,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 struct mtd_partition **pparts,
306 unsigned long origin)
307{
308 unsigned long offset;
309 int i;
310 struct cmdline_mtd_partition *part;
311 char *mtd_id = master->name;
312
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 /* parse command line */
314 if (!cmdline_parsed)
315 mtdpart_setup_real(cmdline);
316
317 for(part = partitions; part; part = part->next)
318 {
319 if ((!mtd_id) || (!strcmp(part->mtd_id, mtd_id)))
320 {
321 for(i = 0, offset = 0; i < part->num_parts; i++)
322 {
Atsushi Nemotob175d032006-03-31 02:29:46 -0800323 if (part->parts[i].offset == OFFSET_CONTINUOUS)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 part->parts[i].offset = offset;
325 else
326 offset = part->parts[i].offset;
327 if (part->parts[i].size == SIZE_REMAINING)
328 part->parts[i].size = master->size - offset;
329 if (offset + part->parts[i].size > master->size)
330 {
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000331 printk(KERN_WARNING ERRP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 "%s: partitioning exceeds flash size, truncating\n",
333 part->mtd_id);
334 part->parts[i].size = master->size - offset;
335 part->num_parts = i;
336 }
337 offset += part->parts[i].size;
338 }
339 *pparts = part->parts;
340 return part->num_parts;
341 }
342 }
Peter Korsgaardb0d06af2008-02-14 17:00:10 +0100343 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344}
345
346
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000347/*
348 * This is the handler for our kernel parameter, called from
Linus Torvalds1da177e2005-04-16 15:20:36 -0700349 * main.c::checksetup(). Note that we can not yet kmalloc() anything,
350 * so we only save the commandline for later processing.
351 *
352 * This function needs to be visible for bootloaders.
353 */
Adrian Bunkddacff12006-11-25 20:15:41 +0100354static int mtdpart_setup(char *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355{
356 cmdline = s;
357 return 1;
358}
359
360__setup("mtdparts=", mtdpart_setup);
361
362static struct mtd_part_parser cmdline_parser = {
363 .owner = THIS_MODULE,
364 .parse_fn = parse_cmdline_partitions,
365 .name = "cmdlinepart",
366};
367
368static int __init cmdline_parser_init(void)
369{
370 return register_mtd_parser(&cmdline_parser);
371}
372
373module_init(cmdline_parser_init);
374
375MODULE_LICENSE("GPL");
376MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
377MODULE_DESCRIPTION("Command line configuration of MTD partitions");