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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * Read flash partition table from command line
3 *
4 * Copyright 2002 SYSGO Real-Time Solutions GmbH
5 *
6 * The format for the command line is as follows:
Thomas Gleixner97894cd2005-11-07 11:15:26 +00007 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * mtdparts=<mtddef>[;<mtddef]
9 * <mtddef> := <mtd-id>:<partdef>[,<partdef>]
Philip Rakitya0ee24a2008-10-08 16:32:11 -070010 * where <mtd-id> is the name from the "cat /proc/mtd" command
Justin Treone619a752008-01-30 10:25:49 -080011 * <partdef> := <size>[@offset][<name>][ro][lk]
Linus Torvalds1da177e2005-04-16 15:20:36 -070012 * <mtd-id> := unique name used in mapping driver/device (mtd->name)
13 * <size> := standard linux memsize OR "-" to denote all remaining space
14 * <name> := '(' NAME ')'
Thomas Gleixner97894cd2005-11-07 11:15:26 +000015 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070016 * Examples:
Thomas Gleixner97894cd2005-11-07 11:15:26 +000017 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070018 * 1 NOR Flash, with 1 single writable partition:
19 * edb7312-nor:-
Thomas Gleixner97894cd2005-11-07 11:15:26 +000020 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070021 * 1 NOR Flash with 2 partitions, 1 NAND with one
22 * edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)
23 */
24
25#include <linux/kernel.h>
26#include <linux/slab.h>
27
28#include <linux/mtd/mtd.h>
29#include <linux/mtd/partitions.h>
30#include <linux/bootmem.h>
31
32/* error message prefix */
33#define ERRP "mtd: "
34
35/* debug macro */
36#if 0
37#define dbg(x) do { printk("DEBUG-CMDLINE-PART: "); printk x; } while(0)
38#else
39#define dbg(x)
40#endif
41
42
43/* special size referring to all the remaining space in a partition */
Atsushi Nemotob175d032006-03-31 02:29:46 -080044#define SIZE_REMAINING UINT_MAX
45#define OFFSET_CONTINUOUS UINT_MAX
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47struct cmdline_mtd_partition {
48 struct cmdline_mtd_partition *next;
49 char *mtd_id;
50 int num_parts;
51 struct mtd_partition *parts;
52};
53
54/* mtdpart_setup() parses into here */
55static struct cmdline_mtd_partition *partitions;
56
57/* the command line passed to mtdpart_setupd() */
58static char *cmdline;
59static int cmdline_parsed = 0;
60
61/*
62 * Parse one partition definition for an MTD. Since there can be many
Thomas Gleixner97894cd2005-11-07 11:15:26 +000063 * comma separated partition definitions, this function calls itself
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 * recursively until no more partition definitions are found. Nice side
65 * effect: the memory to keep the mtd_partition structs and the names
66 * is allocated upon the last definition being found. At that point the
67 * syntax has been verified ok.
68 */
Thomas Gleixner97894cd2005-11-07 11:15:26 +000069static struct mtd_partition * newpart(char *s,
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 char **retptr,
71 int *num_parts,
Thomas Gleixner97894cd2005-11-07 11:15:26 +000072 int this_part,
73 unsigned char **extra_mem_ptr,
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 int extra_mem_size)
75{
76 struct mtd_partition *parts;
77 unsigned long size;
Atsushi Nemotob175d032006-03-31 02:29:46 -080078 unsigned long offset = OFFSET_CONTINUOUS;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 char *name;
80 int name_len;
81 unsigned char *extra_mem;
82 char delim;
83 unsigned int mask_flags;
84
85 /* fetch the partition size */
86 if (*s == '-')
87 { /* assign all remaining space to this partition */
88 size = SIZE_REMAINING;
89 s++;
90 }
91 else
92 {
93 size = memparse(s, &s);
94 if (size < PAGE_SIZE)
95 {
96 printk(KERN_ERR ERRP "partition size too small (%lx)\n", size);
97 return NULL;
98 }
99 }
100
101 /* fetch partition name and flags */
102 mask_flags = 0; /* this is going to be a regular partition */
103 delim = 0;
104 /* check for offset */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000105 if (*s == '@')
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 {
107 s++;
108 offset = memparse(s, &s);
109 }
110 /* now look for name */
111 if (*s == '(')
112 {
113 delim = ')';
114 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000115
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 if (delim)
117 {
118 char *p;
119
120 name = ++s;
Adrian Bunked262c42008-04-14 17:20:04 +0300121 p = strchr(name, delim);
122 if (!p)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123 {
124 printk(KERN_ERR ERRP "no closing %c found in partition name\n", delim);
125 return NULL;
126 }
127 name_len = p - name;
128 s = p + 1;
129 }
130 else
131 {
132 name = NULL;
133 name_len = 13; /* Partition_000 */
134 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000135
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 /* record name length for memory allocation later */
137 extra_mem_size += name_len + 1;
138
139 /* test for options */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000140 if (strncmp(s, "ro", 2) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 {
142 mask_flags |= MTD_WRITEABLE;
143 s += 2;
144 }
145
Justin Treone619a752008-01-30 10:25:49 -0800146 /* if lk is found do NOT unlock the MTD partition*/
147 if (strncmp(s, "lk", 2) == 0)
148 {
149 mask_flags |= MTD_POWERUP_LOCK;
150 s += 2;
151 }
152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 /* test if more partitions are following */
154 if (*s == ',')
155 {
156 if (size == SIZE_REMAINING)
157 {
158 printk(KERN_ERR ERRP "no partitions allowed after a fill-up partition\n");
159 return NULL;
160 }
161 /* more partitions follow, parse them */
Adrian Bunked262c42008-04-14 17:20:04 +0300162 parts = newpart(s + 1, &s, num_parts, this_part + 1,
163 &extra_mem, extra_mem_size);
164 if (!parts)
165 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166 }
167 else
168 { /* this is the last partition: allocate space for all */
169 int alloc_size;
170
171 *num_parts = this_part + 1;
172 alloc_size = *num_parts * sizeof(struct mtd_partition) +
173 extra_mem_size;
Burman Yan95b93a02006-11-15 21:10:29 +0200174 parts = kzalloc(alloc_size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 if (!parts)
176 {
177 printk(KERN_ERR ERRP "out of memory\n");
178 return NULL;
179 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 extra_mem = (unsigned char *)(parts + *num_parts);
181 }
182 /* enter this partition (offset will be calculated later if it is zero at this point) */
183 parts[this_part].size = size;
184 parts[this_part].offset = offset;
185 parts[this_part].mask_flags = mask_flags;
186 if (name)
187 {
188 strlcpy(extra_mem, name, name_len + 1);
189 }
190 else
191 {
192 sprintf(extra_mem, "Partition_%03d", this_part);
193 }
194 parts[this_part].name = extra_mem;
195 extra_mem += name_len + 1;
196
Thadeu Lima de Souza Cascardo342ba102009-06-24 18:39:09 -0300197 dbg(("partition %d: name <%s>, offset %llx, size %llx, mask flags %x\n",
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000198 this_part,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 parts[this_part].name,
200 parts[this_part].offset,
201 parts[this_part].size,
202 parts[this_part].mask_flags));
203
204 /* return (updated) pointer to extra_mem memory */
205 if (extra_mem_ptr)
206 *extra_mem_ptr = extra_mem;
207
208 /* return (updated) pointer command line string */
209 *retptr = s;
210
211 /* return partition table */
212 return parts;
213}
214
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000215/*
216 * Parse the command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 */
218static int mtdpart_setup_real(char *s)
219{
220 cmdline_parsed = 1;
221
222 for( ; s != NULL; )
223 {
224 struct cmdline_mtd_partition *this_mtd;
225 struct mtd_partition *parts;
226 int mtd_id_len;
227 int num_parts;
228 char *p, *mtd_id;
229
230 mtd_id = s;
231 /* fetch <mtd-id> */
232 if (!(p = strchr(s, ':')))
233 {
234 printk(KERN_ERR ERRP "no mtd-id\n");
235 return 0;
236 }
237 mtd_id_len = p - mtd_id;
238
239 dbg(("parsing <%s>\n", p+1));
240
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000241 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 * parse one mtd. have it reserve memory for the
243 * struct cmdline_mtd_partition and the mtd-id string.
244 */
245 parts = newpart(p + 1, /* cmdline */
246 &s, /* out: updated cmdline ptr */
247 &num_parts, /* out: number of parts */
248 0, /* first partition */
249 (unsigned char**)&this_mtd, /* out: extra mem */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000250 mtd_id_len + 1 + sizeof(*this_mtd) +
Joern Engelbe76c5f2005-06-07 16:04:29 +0100251 sizeof(void*)-1 /*alignment*/);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 if(!parts)
253 {
254 /*
255 * An error occurred. We're either:
256 * a) out of memory, or
257 * b) in the middle of the partition spec
258 * Either way, this mtd is hosed and we're
259 * unlikely to succeed in parsing any more
260 */
261 return 0;
262 }
263
Joern Engelbe76c5f2005-06-07 16:04:29 +0100264 /* align this_mtd */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000265 this_mtd = (struct cmdline_mtd_partition *)
Joern Engelbe76c5f2005-06-07 16:04:29 +0100266 ALIGN((unsigned long)this_mtd, sizeof(void*));
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000267 /* enter results */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 this_mtd->parts = parts;
269 this_mtd->num_parts = num_parts;
270 this_mtd->mtd_id = (char*)(this_mtd + 1);
271 strlcpy(this_mtd->mtd_id, mtd_id, mtd_id_len + 1);
272
273 /* link into chain */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000274 this_mtd->next = partitions;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 partitions = this_mtd;
276
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000277 dbg(("mtdid=<%s> num_parts=<%d>\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 this_mtd->mtd_id, this_mtd->num_parts));
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000279
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280
281 /* EOS - we're done */
282 if (*s == 0)
283 break;
284
285 /* does another spec follow? */
286 if (*s != ';')
287 {
288 printk(KERN_ERR ERRP "bad character after partition (%c)\n", *s);
289 return 0;
290 }
291 s++;
292 }
293 return 1;
294}
295
296/*
297 * Main function to be called from the MTD mapping driver/device to
298 * obtain the partitioning information. At this point the command line
299 * arguments will actually be parsed and turned to struct mtd_partition
300 * information. It returns partitions for the requested mtd device, or
301 * the first one in the chain if a NULL mtd_id is passed in.
302 */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000303static int parse_cmdline_partitions(struct mtd_info *master,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 struct mtd_partition **pparts,
305 unsigned long origin)
306{
307 unsigned long offset;
308 int i;
309 struct cmdline_mtd_partition *part;
David Howells36560d22008-07-08 17:09:03 +0100310 const char *mtd_id = master->name;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 /* parse command line */
313 if (!cmdline_parsed)
314 mtdpart_setup_real(cmdline);
315
316 for(part = partitions; part; part = part->next)
317 {
318 if ((!mtd_id) || (!strcmp(part->mtd_id, mtd_id)))
319 {
320 for(i = 0, offset = 0; i < part->num_parts; i++)
321 {
Atsushi Nemotob175d032006-03-31 02:29:46 -0800322 if (part->parts[i].offset == OFFSET_CONTINUOUS)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 part->parts[i].offset = offset;
324 else
325 offset = part->parts[i].offset;
326 if (part->parts[i].size == SIZE_REMAINING)
327 part->parts[i].size = master->size - offset;
328 if (offset + part->parts[i].size > master->size)
329 {
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000330 printk(KERN_WARNING ERRP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 "%s: partitioning exceeds flash size, truncating\n",
332 part->mtd_id);
333 part->parts[i].size = master->size - offset;
334 part->num_parts = i;
335 }
336 offset += part->parts[i].size;
337 }
Atsushi Nemoto17b536c2009-03-06 20:01:08 +0900338 *pparts = kmemdup(part->parts,
339 sizeof(*part->parts) * part->num_parts,
340 GFP_KERNEL);
341 if (!*pparts)
342 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 return part->num_parts;
344 }
345 }
Peter Korsgaardb0d06af2008-02-14 17:00:10 +0100346 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347}
348
349
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000350/*
351 * This is the handler for our kernel parameter, called from
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 * main.c::checksetup(). Note that we can not yet kmalloc() anything,
353 * so we only save the commandline for later processing.
354 *
355 * This function needs to be visible for bootloaders.
356 */
Adrian Bunkddacff12006-11-25 20:15:41 +0100357static int mtdpart_setup(char *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358{
359 cmdline = s;
360 return 1;
361}
362
363__setup("mtdparts=", mtdpart_setup);
364
365static struct mtd_part_parser cmdline_parser = {
366 .owner = THIS_MODULE,
367 .parse_fn = parse_cmdline_partitions,
368 .name = "cmdlinepart",
369};
370
371static int __init cmdline_parser_init(void)
372{
373 return register_mtd_parser(&cmdline_parser);
374}
375
376module_init(cmdline_parser_init);
377
378MODULE_LICENSE("GPL");
379MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
380MODULE_DESCRIPTION("Command line configuration of MTD partitions");