blob: 887629e24c54a5065aa0ee9aca16bbe5d0becc66 [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 Buesoea611b262011-03-22 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 /*
Neil Armstrongf919b922011-11-02 13:37:47 -0700123 * Read 512 bytes further to check if cramfs is padded
124 */
125 sys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0);
126 sys_read(fd, buf, size);
127
128 if (cramfsb->magic == CRAMFS_MAGIC) {
129 printk(KERN_NOTICE
130 "RAMDISK: cramfs filesystem found at block %d\n",
131 start_block);
132 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
133 goto done;
134 }
135
136 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 * Read block 1 to test for minix and ext2 superblock
138 */
139 sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
140 sys_read(fd, buf, size);
141
142 /* Try minix */
143 if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
144 minixsb->s_magic == MINIX_SUPER_MAGIC2) {
145 printk(KERN_NOTICE
146 "RAMDISK: Minix filesystem found at block %d\n",
147 start_block);
148 nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
149 goto done;
150 }
151
152 /* Try ext2 */
153 if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) {
154 printk(KERN_NOTICE
155 "RAMDISK: ext2 filesystem found at block %d\n",
156 start_block);
157 nblocks = le32_to_cpu(ext2sb->s_blocks_count) <<
158 le32_to_cpu(ext2sb->s_log_block_size);
159 goto done;
160 }
161
162 printk(KERN_NOTICE
163 "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
164 start_block);
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800165
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166done:
167 sys_lseek(fd, start_block * BLOCK_SIZE, 0);
168 kfree(buf);
169 return nblocks;
170}
171
172int __init rd_load_image(char *from)
173{
174 int res = 0;
175 int in_fd, out_fd;
176 unsigned long rd_blocks, devblocks;
177 int nblocks, i, disk;
178 char *buf = NULL;
179 unsigned short rotate = 0;
Alain Knaff30d65db2009-01-04 22:46:17 +0100180 decompress_fn decompressor = NULL;
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800181#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 char rotator[4] = { '|' , '/' , '-' , '\\' };
183#endif
184
Namhyung Kim562f5e62010-10-26 14:22:42 -0700185 out_fd = sys_open((const char __user __force *) "/dev/ram", O_RDWR, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 if (out_fd < 0)
187 goto out;
188
189 in_fd = sys_open(from, O_RDONLY, 0);
190 if (in_fd < 0)
191 goto noclose_input;
192
Alain Knaff30d65db2009-01-04 22:46:17 +0100193 nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 if (nblocks < 0)
195 goto done;
196
197 if (nblocks == 0) {
Alain Knaff30d65db2009-01-04 22:46:17 +0100198 if (crd_load(in_fd, out_fd, decompressor) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 goto successful_load;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700200 goto done;
201 }
202
203 /*
204 * NOTE NOTE: nblocks is not actually blocks but
205 * the number of kibibytes of data to load into a ramdisk.
206 * So any ramdisk block size that is a multiple of 1KiB should
207 * work when the appropriate ramdisk_blocksize is specified
208 * on the command line.
209 *
210 * The default ramdisk_blocksize is 1KiB and it is generally
211 * silly to use anything else, so make sure to use 1KiB
212 * blocksize while generating ext2fs ramdisk-images.
213 */
214 if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
215 rd_blocks = 0;
216 else
217 rd_blocks >>= 1;
218
219 if (nblocks > rd_blocks) {
220 printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
221 nblocks, rd_blocks);
222 goto done;
223 }
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800224
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 /*
226 * OK, time to copy in the data
227 */
228 if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
229 devblocks = 0;
230 else
231 devblocks >>= 1;
232
233 if (strcmp(from, "/initrd.image") == 0)
234 devblocks = nblocks;
235
236 if (devblocks == 0) {
237 printk(KERN_ERR "RAMDISK: could not determine device size\n");
238 goto done;
239 }
240
241 buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
Harvey Harrisond613c3e2008-04-28 14:13:14 -0700242 if (!buf) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
244 goto done;
245 }
246
247 printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
248 nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
249 for (i = 0, disk = 1; i < nblocks; i++) {
250 if (i && (i % devblocks == 0)) {
251 printk("done disk #%d.\n", disk++);
252 rotate = 0;
253 if (sys_close(in_fd)) {
254 printk("Error closing the disk.\n");
255 goto noclose_input;
256 }
257 change_floppy("disk #%d", disk);
258 in_fd = sys_open(from, O_RDONLY, 0);
259 if (in_fd < 0) {
260 printk("Error opening disk.\n");
261 goto noclose_input;
262 }
263 printk("Loading disk #%d... ", disk);
264 }
265 sys_read(in_fd, buf, BLOCK_SIZE);
266 sys_write(out_fd, buf, BLOCK_SIZE);
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800267#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 if (!(i % 16)) {
269 printk("%c\b", rotator[rotate & 0x3]);
270 rotate++;
271 }
272#endif
273 }
274 printk("done.\n");
275
276successful_load:
277 res = 1;
278done:
279 sys_close(in_fd);
280noclose_input:
281 sys_close(out_fd);
282out:
283 kfree(buf);
Namhyung Kim562f5e62010-10-26 14:22:42 -0700284 sys_unlink((const char __user __force *) "/dev/ram");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 return res;
286}
287
288int __init rd_load_disk(int n)
289{
290 if (rd_prompt)
291 change_floppy("root floppy disk to be loaded into RAM disk");
Greg Kroah-Hartmanbdaf8522005-06-20 21:15:16 -0700292 create_dev("/dev/root", ROOT_DEV);
293 create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 return rd_load_image("/dev/root");
295}
296
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297static int exit_code;
Alain Knaff30d65db2009-01-04 22:46:17 +0100298static int decompress_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299static int crd_infd, crd_outfd;
300
Alain Knaff30d65db2009-01-04 22:46:17 +0100301static int __init compr_fill(void *buf, unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302{
Alain Knaff30d65db2009-01-04 22:46:17 +0100303 int r = sys_read(crd_infd, buf, len);
304 if (r < 0)
305 printk(KERN_ERR "RAMDISK: error while reading compressed data");
306 else if (r == 0)
307 printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
308 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309}
310
Alain Knaff30d65db2009-01-04 22:46:17 +0100311static int __init compr_flush(void *window, unsigned int outcnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312{
Alain Knaff30d65db2009-01-04 22:46:17 +0100313 int written = sys_write(crd_outfd, window, outcnt);
314 if (written != outcnt) {
315 if (decompress_error == 0)
316 printk(KERN_ERR
317 "RAMDISK: incomplete write (%d != %d)\n",
318 written, outcnt);
319 decompress_error = 1;
320 return -1;
321 }
322 return outcnt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323}
324
325static void __init error(char *x)
326{
327 printk(KERN_ERR "%s\n", x);
328 exit_code = 1;
Alain Knaff30d65db2009-01-04 22:46:17 +0100329 decompress_error = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330}
331
Alain Knaff30d65db2009-01-04 22:46:17 +0100332static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333{
334 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 crd_infd = in_fd;
336 crd_outfd = out_fd;
Alain Knaff30d65db2009-01-04 22:46:17 +0100337 result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
338 if (decompress_error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 result = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340 return result;
341}