blob: 6212586df29ace81e239b71d01b95826cb636507 [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;
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 struct romfs_super_block *romfsb;
58 struct cramfs_super *cramfsb;
Phillip Lougherb8fed872009-01-05 08:46:28 +000059 struct squashfs_super_block *squashfsb;
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 int nblocks = -1;
61 unsigned char *buf;
H. Peter Anvin889c92d2009-01-08 15:14:17 -080062 const char *compress_name;
Al Viro39429c52012-03-23 16:36:45 -040063 unsigned long n;
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;
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 romfsb = (struct romfs_super_block *) buf;
71 cramfsb = (struct cramfs_super *) buf;
Phillip Lougherb8fed872009-01-05 08:46:28 +000072 squashfsb = (struct squashfs_super_block *) buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 memset(buf, 0xe5, size);
74
75 /*
H. Peter Anvinb172fd82009-01-04 14:42:52 -080076 * Read block 0 to test for compressed kernel
Linus Torvalds1da177e2005-04-16 15:20:36 -070077 */
78 sys_lseek(fd, start_block * BLOCK_SIZE, 0);
79 sys_read(fd, buf, size);
80
H. Peter Anvin889c92d2009-01-08 15:14:17 -080081 *decompressor = decompress_method(buf, size, &compress_name);
H. Peter Anvin23a22d52009-01-12 14:24:04 -080082 if (compress_name) {
H. Peter Anvin889c92d2009-01-08 15:14:17 -080083 printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
84 compress_name, start_block);
H. Peter Anvin23a22d52009-01-12 14:24:04 -080085 if (!*decompressor)
H. Peter Anvin73310a12009-01-14 11:28:35 -080086 printk(KERN_EMERG
87 "RAMDISK: %s decompressor not configured!\n",
H. Peter Anvin23a22d52009-01-12 14:24:04 -080088 compress_name);
H. Peter Anvin889c92d2009-01-08 15:14:17 -080089 nblocks = 0;
90 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 }
92
93 /* romfs is at block zero too */
94 if (romfsb->word0 == ROMSB_WORD0 &&
95 romfsb->word1 == ROMSB_WORD1) {
96 printk(KERN_NOTICE
97 "RAMDISK: romfs filesystem found at block %d\n",
98 start_block);
99 nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
100 goto done;
101 }
102
103 if (cramfsb->magic == CRAMFS_MAGIC) {
104 printk(KERN_NOTICE
105 "RAMDISK: cramfs filesystem found at block %d\n",
106 start_block);
107 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
108 goto done;
109 }
110
Phillip Lougherb8fed872009-01-05 08:46:28 +0000111 /* squashfs is at block zero too */
112 if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) {
113 printk(KERN_NOTICE
114 "RAMDISK: squashfs filesystem found at block %d\n",
115 start_block);
116 nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1)
117 >> BLOCK_SIZE_BITS;
118 goto done;
119 }
120
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121 /*
Neil Armstrongf919b922011-11-02 13:37:47 -0700122 * Read 512 bytes further to check if cramfs is padded
123 */
124 sys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0);
125 sys_read(fd, buf, size);
126
127 if (cramfsb->magic == CRAMFS_MAGIC) {
128 printk(KERN_NOTICE
129 "RAMDISK: cramfs filesystem found at block %d\n",
130 start_block);
131 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
132 goto done;
133 }
134
135 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 * Read block 1 to test for minix and ext2 superblock
137 */
138 sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
139 sys_read(fd, buf, size);
140
141 /* Try minix */
142 if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
143 minixsb->s_magic == MINIX_SUPER_MAGIC2) {
144 printk(KERN_NOTICE
145 "RAMDISK: Minix filesystem found at block %d\n",
146 start_block);
147 nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
148 goto done;
149 }
150
151 /* Try ext2 */
Al Viro39429c52012-03-23 16:36:45 -0400152 n = ext2_image_size(buf);
153 if (n) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 printk(KERN_NOTICE
155 "RAMDISK: ext2 filesystem found at block %d\n",
156 start_block);
Al Viro39429c52012-03-23 16:36:45 -0400157 nblocks = n;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 goto done;
159 }
160
161 printk(KERN_NOTICE
162 "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
163 start_block);
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800164
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165done:
166 sys_lseek(fd, start_block * BLOCK_SIZE, 0);
167 kfree(buf);
168 return nblocks;
169}
170
171int __init rd_load_image(char *from)
172{
173 int res = 0;
174 int in_fd, out_fd;
175 unsigned long rd_blocks, devblocks;
176 int nblocks, i, disk;
177 char *buf = NULL;
178 unsigned short rotate = 0;
Alain Knaff30d65db2009-01-04 22:46:17 +0100179 decompress_fn decompressor = NULL;
Stephen Rothwellbc584502012-03-15 18:19:08 +0000180#if !defined(CONFIG_S390)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 char rotator[4] = { '|' , '/' , '-' , '\\' };
182#endif
183
Namhyung Kim562f5e62010-10-26 14:22:42 -0700184 out_fd = sys_open((const char __user __force *) "/dev/ram", O_RDWR, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 if (out_fd < 0)
186 goto out;
187
188 in_fd = sys_open(from, O_RDONLY, 0);
189 if (in_fd < 0)
190 goto noclose_input;
191
Alain Knaff30d65db2009-01-04 22:46:17 +0100192 nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 if (nblocks < 0)
194 goto done;
195
196 if (nblocks == 0) {
Alain Knaff30d65db2009-01-04 22:46:17 +0100197 if (crd_load(in_fd, out_fd, decompressor) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 goto successful_load;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 goto done;
200 }
201
202 /*
203 * NOTE NOTE: nblocks is not actually blocks but
204 * the number of kibibytes of data to load into a ramdisk.
205 * So any ramdisk block size that is a multiple of 1KiB should
206 * work when the appropriate ramdisk_blocksize is specified
207 * on the command line.
208 *
209 * The default ramdisk_blocksize is 1KiB and it is generally
210 * silly to use anything else, so make sure to use 1KiB
211 * blocksize while generating ext2fs ramdisk-images.
212 */
213 if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
214 rd_blocks = 0;
215 else
216 rd_blocks >>= 1;
217
218 if (nblocks > rd_blocks) {
219 printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
220 nblocks, rd_blocks);
221 goto done;
222 }
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800223
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 /*
225 * OK, time to copy in the data
226 */
227 if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
228 devblocks = 0;
229 else
230 devblocks >>= 1;
231
232 if (strcmp(from, "/initrd.image") == 0)
233 devblocks = nblocks;
234
235 if (devblocks == 0) {
236 printk(KERN_ERR "RAMDISK: could not determine device size\n");
237 goto done;
238 }
239
240 buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
Harvey Harrisond613c3e2008-04-28 14:13:14 -0700241 if (!buf) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
243 goto done;
244 }
245
246 printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
247 nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
248 for (i = 0, disk = 1; i < nblocks; i++) {
249 if (i && (i % devblocks == 0)) {
250 printk("done disk #%d.\n", disk++);
251 rotate = 0;
252 if (sys_close(in_fd)) {
253 printk("Error closing the disk.\n");
254 goto noclose_input;
255 }
256 change_floppy("disk #%d", disk);
257 in_fd = sys_open(from, O_RDONLY, 0);
258 if (in_fd < 0) {
259 printk("Error opening disk.\n");
260 goto noclose_input;
261 }
262 printk("Loading disk #%d... ", disk);
263 }
264 sys_read(in_fd, buf, BLOCK_SIZE);
265 sys_write(out_fd, buf, BLOCK_SIZE);
Stephen Rothwellbc584502012-03-15 18:19:08 +0000266#if !defined(CONFIG_S390)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 if (!(i % 16)) {
268 printk("%c\b", rotator[rotate & 0x3]);
269 rotate++;
270 }
271#endif
272 }
273 printk("done.\n");
274
275successful_load:
276 res = 1;
277done:
278 sys_close(in_fd);
279noclose_input:
280 sys_close(out_fd);
281out:
282 kfree(buf);
Namhyung Kim562f5e62010-10-26 14:22:42 -0700283 sys_unlink((const char __user __force *) "/dev/ram");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 return res;
285}
286
287int __init rd_load_disk(int n)
288{
289 if (rd_prompt)
290 change_floppy("root floppy disk to be loaded into RAM disk");
Greg Kroah-Hartmanbdaf8522005-06-20 21:15:16 -0700291 create_dev("/dev/root", ROOT_DEV);
292 create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 return rd_load_image("/dev/root");
294}
295
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296static int exit_code;
Alain Knaff30d65db2009-01-04 22:46:17 +0100297static int decompress_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298static int crd_infd, crd_outfd;
299
Alain Knaff30d65db2009-01-04 22:46:17 +0100300static int __init compr_fill(void *buf, unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301{
Alain Knaff30d65db2009-01-04 22:46:17 +0100302 int r = sys_read(crd_infd, buf, len);
303 if (r < 0)
304 printk(KERN_ERR "RAMDISK: error while reading compressed data");
305 else if (r == 0)
306 printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
307 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308}
309
Alain Knaff30d65db2009-01-04 22:46:17 +0100310static int __init compr_flush(void *window, unsigned int outcnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311{
Alain Knaff30d65db2009-01-04 22:46:17 +0100312 int written = sys_write(crd_outfd, window, outcnt);
313 if (written != outcnt) {
314 if (decompress_error == 0)
315 printk(KERN_ERR
316 "RAMDISK: incomplete write (%d != %d)\n",
317 written, outcnt);
318 decompress_error = 1;
319 return -1;
320 }
321 return outcnt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322}
323
324static void __init error(char *x)
325{
326 printk(KERN_ERR "%s\n", x);
327 exit_code = 1;
Alain Knaff30d65db2009-01-04 22:46:17 +0100328 decompress_error = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329}
330
Alain Knaff30d65db2009-01-04 22:46:17 +0100331static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332{
333 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 crd_infd = in_fd;
335 crd_outfd = out_fd;
Alain Knaff30d65db2009-01-04 22:46:17 +0100336 result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
337 if (decompress_error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 result = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 return result;
340}