blob: fe9acb0ae4808bd663187d802960d788f73276c1 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001
2#include <linux/kernel.h>
3#include <linux/fs.h>
4#include <linux/minix_fs.h>
5#include <linux/ext2_fs.h>
6#include <linux/romfs_fs.h>
7#include <linux/cramfs_fs.h>
8#include <linux/initrd.h>
9#include <linux/string.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090010#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070011
12#include "do_mounts.h"
Phillip Lougherb8fed872009-01-05 08:46:28 +000013#include "../fs/squashfs/squashfs_fs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070014
Alain Knaff30d65db2009-01-04 22:46:17 +010015#include <linux/decompress/generic.h>
16
Alain Knaff30d65db2009-01-04 22:46:17 +010017
Linus Torvalds1da177e2005-04-16 15:20:36 -070018int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */
19
20static int __init prompt_ramdisk(char *str)
21{
22 rd_prompt = simple_strtol(str,NULL,0) & 1;
23 return 1;
24}
25__setup("prompt_ramdisk=", prompt_ramdisk);
26
27int __initdata rd_image_start; /* starting block # of image */
28
29static int __init ramdisk_start_setup(char *str)
30{
31 rd_image_start = simple_strtol(str,NULL,0);
32 return 1;
33}
34__setup("ramdisk_start=", ramdisk_start_setup);
35
Alain Knaff30d65db2009-01-04 22:46:17 +010036static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38/*
39 * This routine tries to find a RAM disk image to load, and returns the
40 * number of blocks to read for a non-compressed image, 0 if the image
41 * is a compressed image, and -1 if an image with the right magic
42 * numbers could not be found.
43 *
44 * We currently check for the following magic numbers:
H. Peter Anvinb172fd82009-01-04 14:42:52 -080045 * minix
46 * ext2
Linus Torvalds1da177e2005-04-16 15:20:36 -070047 * romfs
48 * cramfs
Phillip Lougherb8fed872009-01-05 08:46:28 +000049 * squashfs
H. Peter Anvinb172fd82009-01-04 14:42:52 -080050 * gzip
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 */
H. Peter Anvinb172fd82009-01-04 14:42:52 -080052static int __init
Alain Knaff30d65db2009-01-04 22:46:17 +010053identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)
Linus Torvalds1da177e2005-04-16 15:20:36 -070054{
55 const int size = 512;
56 struct minix_super_block *minixsb;
57 struct ext2_super_block *ext2sb;
58 struct romfs_super_block *romfsb;
59 struct cramfs_super *cramfsb;
Phillip Lougherb8fed872009-01-05 08:46:28 +000060 struct squashfs_super_block *squashfsb;
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 int nblocks = -1;
62 unsigned char *buf;
H. Peter Anvin889c92d2009-01-08 15:14:17 -080063 const char *compress_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65 buf = kmalloc(size, GFP_KERNEL);
Stephen Hemmingerc80544d2007-10-18 03:07:05 -070066 if (!buf)
Davidlohr Buesoea611b22011-03-22 16:34:49 -070067 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69 minixsb = (struct minix_super_block *) buf;
70 ext2sb = (struct ext2_super_block *) buf;
71 romfsb = (struct romfs_super_block *) buf;
72 cramfsb = (struct cramfs_super *) buf;
Phillip Lougherb8fed872009-01-05 08:46:28 +000073 squashfsb = (struct squashfs_super_block *) buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 memset(buf, 0xe5, size);
75
76 /*
H. Peter Anvinb172fd82009-01-04 14:42:52 -080077 * Read block 0 to test for compressed kernel
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 */
79 sys_lseek(fd, start_block * BLOCK_SIZE, 0);
80 sys_read(fd, buf, size);
81
H. Peter Anvin889c92d2009-01-08 15:14:17 -080082 *decompressor = decompress_method(buf, size, &compress_name);
H. Peter Anvin23a22d52009-01-12 14:24:04 -080083 if (compress_name) {
H. Peter Anvin889c92d2009-01-08 15:14:17 -080084 printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
85 compress_name, start_block);
H. Peter Anvin23a22d52009-01-12 14:24:04 -080086 if (!*decompressor)
H. Peter Anvin73310a12009-01-14 11:28:35 -080087 printk(KERN_EMERG
88 "RAMDISK: %s decompressor not configured!\n",
H. Peter Anvin23a22d52009-01-12 14:24:04 -080089 compress_name);
H. Peter Anvin889c92d2009-01-08 15:14:17 -080090 nblocks = 0;
91 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 }
93
94 /* romfs is at block zero too */
95 if (romfsb->word0 == ROMSB_WORD0 &&
96 romfsb->word1 == ROMSB_WORD1) {
97 printk(KERN_NOTICE
98 "RAMDISK: romfs filesystem found at block %d\n",
99 start_block);
100 nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
101 goto done;
102 }
103
104 if (cramfsb->magic == CRAMFS_MAGIC) {
105 printk(KERN_NOTICE
106 "RAMDISK: cramfs filesystem found at block %d\n",
107 start_block);
108 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
109 goto done;
110 }
111
Phillip Lougherb8fed872009-01-05 08:46:28 +0000112 /* squashfs is at block zero too */
113 if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) {
114 printk(KERN_NOTICE
115 "RAMDISK: squashfs filesystem found at block %d\n",
116 start_block);
117 nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1)
118 >> BLOCK_SIZE_BITS;
119 goto done;
120 }
121
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 /*
123 * Read block 1 to test for minix and ext2 superblock
124 */
125 sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
126 sys_read(fd, buf, size);
127
128 /* Try minix */
129 if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
130 minixsb->s_magic == MINIX_SUPER_MAGIC2) {
131 printk(KERN_NOTICE
132 "RAMDISK: Minix filesystem found at block %d\n",
133 start_block);
134 nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
135 goto done;
136 }
137
138 /* Try ext2 */
139 if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) {
140 printk(KERN_NOTICE
141 "RAMDISK: ext2 filesystem found at block %d\n",
142 start_block);
143 nblocks = le32_to_cpu(ext2sb->s_blocks_count) <<
144 le32_to_cpu(ext2sb->s_log_block_size);
145 goto done;
146 }
147
148 printk(KERN_NOTICE
149 "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
150 start_block);
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800151
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152done:
153 sys_lseek(fd, start_block * BLOCK_SIZE, 0);
154 kfree(buf);
155 return nblocks;
156}
157
158int __init rd_load_image(char *from)
159{
160 int res = 0;
161 int in_fd, out_fd;
162 unsigned long rd_blocks, devblocks;
163 int nblocks, i, disk;
164 char *buf = NULL;
165 unsigned short rotate = 0;
Alain Knaff30d65db2009-01-04 22:46:17 +0100166 decompress_fn decompressor = NULL;
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800167#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 char rotator[4] = { '|' , '/' , '-' , '\\' };
169#endif
170
Namhyung Kim562f5e62010-10-26 14:22:42 -0700171 out_fd = sys_open((const char __user __force *) "/dev/ram", O_RDWR, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 if (out_fd < 0)
173 goto out;
174
175 in_fd = sys_open(from, O_RDONLY, 0);
176 if (in_fd < 0)
177 goto noclose_input;
178
Alain Knaff30d65db2009-01-04 22:46:17 +0100179 nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 if (nblocks < 0)
181 goto done;
182
183 if (nblocks == 0) {
Alain Knaff30d65db2009-01-04 22:46:17 +0100184 if (crd_load(in_fd, out_fd, decompressor) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 goto successful_load;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 goto done;
187 }
188
189 /*
190 * NOTE NOTE: nblocks is not actually blocks but
191 * the number of kibibytes of data to load into a ramdisk.
192 * So any ramdisk block size that is a multiple of 1KiB should
193 * work when the appropriate ramdisk_blocksize is specified
194 * on the command line.
195 *
196 * The default ramdisk_blocksize is 1KiB and it is generally
197 * silly to use anything else, so make sure to use 1KiB
198 * blocksize while generating ext2fs ramdisk-images.
199 */
200 if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
201 rd_blocks = 0;
202 else
203 rd_blocks >>= 1;
204
205 if (nblocks > rd_blocks) {
206 printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
207 nblocks, rd_blocks);
208 goto done;
209 }
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800210
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 /*
212 * OK, time to copy in the data
213 */
214 if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
215 devblocks = 0;
216 else
217 devblocks >>= 1;
218
219 if (strcmp(from, "/initrd.image") == 0)
220 devblocks = nblocks;
221
222 if (devblocks == 0) {
223 printk(KERN_ERR "RAMDISK: could not determine device size\n");
224 goto done;
225 }
226
227 buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
Harvey Harrisond613c3e2008-04-28 14:13:14 -0700228 if (!buf) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229 printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
230 goto done;
231 }
232
233 printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
234 nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
235 for (i = 0, disk = 1; i < nblocks; i++) {
236 if (i && (i % devblocks == 0)) {
237 printk("done disk #%d.\n", disk++);
238 rotate = 0;
239 if (sys_close(in_fd)) {
240 printk("Error closing the disk.\n");
241 goto noclose_input;
242 }
243 change_floppy("disk #%d", disk);
244 in_fd = sys_open(from, O_RDONLY, 0);
245 if (in_fd < 0) {
246 printk("Error opening disk.\n");
247 goto noclose_input;
248 }
249 printk("Loading disk #%d... ", disk);
250 }
251 sys_read(in_fd, buf, BLOCK_SIZE);
252 sys_write(out_fd, buf, BLOCK_SIZE);
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800253#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 if (!(i % 16)) {
255 printk("%c\b", rotator[rotate & 0x3]);
256 rotate++;
257 }
258#endif
259 }
260 printk("done.\n");
261
262successful_load:
263 res = 1;
264done:
265 sys_close(in_fd);
266noclose_input:
267 sys_close(out_fd);
268out:
269 kfree(buf);
Namhyung Kim562f5e62010-10-26 14:22:42 -0700270 sys_unlink((const char __user __force *) "/dev/ram");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 return res;
272}
273
274int __init rd_load_disk(int n)
275{
276 if (rd_prompt)
277 change_floppy("root floppy disk to be loaded into RAM disk");
Greg Kroah-Hartmanbdaf8522005-06-20 21:15:16 -0700278 create_dev("/dev/root", ROOT_DEV);
279 create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 return rd_load_image("/dev/root");
281}
282
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283static int exit_code;
Alain Knaff30d65db2009-01-04 22:46:17 +0100284static int decompress_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285static int crd_infd, crd_outfd;
286
Alain Knaff30d65db2009-01-04 22:46:17 +0100287static int __init compr_fill(void *buf, unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288{
Alain Knaff30d65db2009-01-04 22:46:17 +0100289 int r = sys_read(crd_infd, buf, len);
290 if (r < 0)
291 printk(KERN_ERR "RAMDISK: error while reading compressed data");
292 else if (r == 0)
293 printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
294 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295}
296
Alain Knaff30d65db2009-01-04 22:46:17 +0100297static int __init compr_flush(void *window, unsigned int outcnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298{
Alain Knaff30d65db2009-01-04 22:46:17 +0100299 int written = sys_write(crd_outfd, window, outcnt);
300 if (written != outcnt) {
301 if (decompress_error == 0)
302 printk(KERN_ERR
303 "RAMDISK: incomplete write (%d != %d)\n",
304 written, outcnt);
305 decompress_error = 1;
306 return -1;
307 }
308 return outcnt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309}
310
311static void __init error(char *x)
312{
313 printk(KERN_ERR "%s\n", x);
314 exit_code = 1;
Alain Knaff30d65db2009-01-04 22:46:17 +0100315 decompress_error = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316}
317
Alain Knaff30d65db2009-01-04 22:46:17 +0100318static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319{
320 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 crd_infd = in_fd;
322 crd_outfd = out_fd;
Alain Knaff30d65db2009-01-04 22:46:17 +0100323 result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
324 if (decompress_error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 result = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 return result;
327}