ia64/linux-2.6.18-xen.hg

view drivers/mtd/cmdlinepart.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /*
2 * $Id: cmdlinepart.c,v 1.19 2005/11/07 11:14:19 gleixner Exp $
3 *
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:
9 *
10 * mtdparts=<mtddef>[;<mtddef]
11 * <mtddef> := <mtd-id>:<partdef>[,<partdef>]
12 * <partdef> := <size>[@offset][<name>][ro]
13 * <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 ')'
16 *
17 * Examples:
18 *
19 * 1 NOR Flash, with 1 single writable partition:
20 * edb7312-nor:-
21 *
22 * 1 NOR Flash with 2 partitions, 1 NAND with one
23 * edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)
24 */
26 #include <linux/kernel.h>
27 #include <linux/slab.h>
29 #include <linux/mtd/mtd.h>
30 #include <linux/mtd/partitions.h>
31 #include <linux/bootmem.h>
33 /* error message prefix */
34 #define ERRP "mtd: "
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
44 /* special size referring to all the remaining space in a partition */
45 #define SIZE_REMAINING UINT_MAX
46 #define OFFSET_CONTINUOUS UINT_MAX
48 struct cmdline_mtd_partition {
49 struct cmdline_mtd_partition *next;
50 char *mtd_id;
51 int num_parts;
52 struct mtd_partition *parts;
53 };
55 /* mtdpart_setup() parses into here */
56 static struct cmdline_mtd_partition *partitions;
58 /* the command line passed to mtdpart_setupd() */
59 static char *cmdline;
60 static int cmdline_parsed = 0;
62 /*
63 * Parse one partition definition for an MTD. Since there can be many
64 * comma separated partition definitions, this function calls itself
65 * 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 */
70 static struct mtd_partition * newpart(char *s,
71 char **retptr,
72 int *num_parts,
73 int this_part,
74 unsigned char **extra_mem_ptr,
75 int extra_mem_size)
76 {
77 struct mtd_partition *parts;
78 unsigned long size;
79 unsigned long offset = OFFSET_CONTINUOUS;
80 char *name;
81 int name_len;
82 unsigned char *extra_mem;
83 char delim;
84 unsigned int mask_flags;
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 }
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 */
106 if (*s == '@')
107 {
108 s++;
109 offset = memparse(s, &s);
110 }
111 /* now look for name */
112 if (*s == '(')
113 {
114 delim = ')';
115 }
117 if (delim)
118 {
119 char *p;
121 name = ++s;
122 if ((p = strchr(name, delim)) == 0)
123 {
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 }
136 /* record name length for memory allocation later */
137 extra_mem_size += name_len + 1;
139 /* test for options */
140 if (strncmp(s, "ro", 2) == 0)
141 {
142 mask_flags |= MTD_WRITEABLE;
143 s += 2;
144 }
146 /* test if more partitions are following */
147 if (*s == ',')
148 {
149 if (size == SIZE_REMAINING)
150 {
151 printk(KERN_ERR ERRP "no partitions allowed after a fill-up partition\n");
152 return NULL;
153 }
154 /* more partitions follow, parse them */
155 if ((parts = newpart(s + 1, &s, num_parts,
156 this_part + 1, &extra_mem, extra_mem_size)) == 0)
157 return NULL;
158 }
159 else
160 { /* this is the last partition: allocate space for all */
161 int alloc_size;
163 *num_parts = this_part + 1;
164 alloc_size = *num_parts * sizeof(struct mtd_partition) +
165 extra_mem_size;
166 parts = kmalloc(alloc_size, GFP_KERNEL);
167 if (!parts)
168 {
169 printk(KERN_ERR ERRP "out of memory\n");
170 return NULL;
171 }
172 memset(parts, 0, alloc_size);
173 extra_mem = (unsigned char *)(parts + *num_parts);
174 }
175 /* enter this partition (offset will be calculated later if it is zero at this point) */
176 parts[this_part].size = size;
177 parts[this_part].offset = offset;
178 parts[this_part].mask_flags = mask_flags;
179 if (name)
180 {
181 strlcpy(extra_mem, name, name_len + 1);
182 }
183 else
184 {
185 sprintf(extra_mem, "Partition_%03d", this_part);
186 }
187 parts[this_part].name = extra_mem;
188 extra_mem += name_len + 1;
190 dbg(("partition %d: name <%s>, offset %x, size %x, mask flags %x\n",
191 this_part,
192 parts[this_part].name,
193 parts[this_part].offset,
194 parts[this_part].size,
195 parts[this_part].mask_flags));
197 /* return (updated) pointer to extra_mem memory */
198 if (extra_mem_ptr)
199 *extra_mem_ptr = extra_mem;
201 /* return (updated) pointer command line string */
202 *retptr = s;
204 /* return partition table */
205 return parts;
206 }
208 /*
209 * Parse the command line.
210 */
211 static int mtdpart_setup_real(char *s)
212 {
213 cmdline_parsed = 1;
215 for( ; s != NULL; )
216 {
217 struct cmdline_mtd_partition *this_mtd;
218 struct mtd_partition *parts;
219 int mtd_id_len;
220 int num_parts;
221 char *p, *mtd_id;
223 mtd_id = s;
224 /* fetch <mtd-id> */
225 if (!(p = strchr(s, ':')))
226 {
227 printk(KERN_ERR ERRP "no mtd-id\n");
228 return 0;
229 }
230 mtd_id_len = p - mtd_id;
232 dbg(("parsing <%s>\n", p+1));
234 /*
235 * parse one mtd. have it reserve memory for the
236 * struct cmdline_mtd_partition and the mtd-id string.
237 */
238 parts = newpart(p + 1, /* cmdline */
239 &s, /* out: updated cmdline ptr */
240 &num_parts, /* out: number of parts */
241 0, /* first partition */
242 (unsigned char**)&this_mtd, /* out: extra mem */
243 mtd_id_len + 1 + sizeof(*this_mtd) +
244 sizeof(void*)-1 /*alignment*/);
245 if(!parts)
246 {
247 /*
248 * An error occurred. We're either:
249 * a) out of memory, or
250 * b) in the middle of the partition spec
251 * Either way, this mtd is hosed and we're
252 * unlikely to succeed in parsing any more
253 */
254 return 0;
255 }
257 /* align this_mtd */
258 this_mtd = (struct cmdline_mtd_partition *)
259 ALIGN((unsigned long)this_mtd, sizeof(void*));
260 /* enter results */
261 this_mtd->parts = parts;
262 this_mtd->num_parts = num_parts;
263 this_mtd->mtd_id = (char*)(this_mtd + 1);
264 strlcpy(this_mtd->mtd_id, mtd_id, mtd_id_len + 1);
266 /* link into chain */
267 this_mtd->next = partitions;
268 partitions = this_mtd;
270 dbg(("mtdid=<%s> num_parts=<%d>\n",
271 this_mtd->mtd_id, this_mtd->num_parts));
274 /* EOS - we're done */
275 if (*s == 0)
276 break;
278 /* does another spec follow? */
279 if (*s != ';')
280 {
281 printk(KERN_ERR ERRP "bad character after partition (%c)\n", *s);
282 return 0;
283 }
284 s++;
285 }
286 return 1;
287 }
289 /*
290 * Main function to be called from the MTD mapping driver/device to
291 * obtain the partitioning information. At this point the command line
292 * arguments will actually be parsed and turned to struct mtd_partition
293 * information. It returns partitions for the requested mtd device, or
294 * the first one in the chain if a NULL mtd_id is passed in.
295 */
296 static int parse_cmdline_partitions(struct mtd_info *master,
297 struct mtd_partition **pparts,
298 unsigned long origin)
299 {
300 unsigned long offset;
301 int i;
302 struct cmdline_mtd_partition *part;
303 char *mtd_id = master->name;
305 if(!cmdline)
306 return -EINVAL;
308 /* parse command line */
309 if (!cmdline_parsed)
310 mtdpart_setup_real(cmdline);
312 for(part = partitions; part; part = part->next)
313 {
314 if ((!mtd_id) || (!strcmp(part->mtd_id, mtd_id)))
315 {
316 for(i = 0, offset = 0; i < part->num_parts; i++)
317 {
318 if (part->parts[i].offset == OFFSET_CONTINUOUS)
319 part->parts[i].offset = offset;
320 else
321 offset = part->parts[i].offset;
322 if (part->parts[i].size == SIZE_REMAINING)
323 part->parts[i].size = master->size - offset;
324 if (offset + part->parts[i].size > master->size)
325 {
326 printk(KERN_WARNING ERRP
327 "%s: partitioning exceeds flash size, truncating\n",
328 part->mtd_id);
329 part->parts[i].size = master->size - offset;
330 part->num_parts = i;
331 }
332 offset += part->parts[i].size;
333 }
334 *pparts = part->parts;
335 return part->num_parts;
336 }
337 }
338 return -EINVAL;
339 }
342 /*
343 * This is the handler for our kernel parameter, called from
344 * main.c::checksetup(). Note that we can not yet kmalloc() anything,
345 * so we only save the commandline for later processing.
346 *
347 * This function needs to be visible for bootloaders.
348 */
349 int mtdpart_setup(char *s)
350 {
351 cmdline = s;
352 return 1;
353 }
355 __setup("mtdparts=", mtdpart_setup);
357 static struct mtd_part_parser cmdline_parser = {
358 .owner = THIS_MODULE,
359 .parse_fn = parse_cmdline_partitions,
360 .name = "cmdlinepart",
361 };
363 static int __init cmdline_parser_init(void)
364 {
365 return register_mtd_parser(&cmdline_parser);
366 }
368 module_init(cmdline_parser_init);
370 MODULE_LICENSE("GPL");
371 MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
372 MODULE_DESCRIPTION("Command line configuration of MTD partitions");