blob: 6be2879cca66971859b1c51ff80451616ab13975 [file] [log] [blame]
H Hartley Sweetenc67e5382012-05-31 16:26:10 -07001/*
2 * Many of the syscalls used in this file expect some of the arguments
3 * to be __user pointers not __kernel pointers. To limit the sparse
4 * noise, turn off sparse checking for this file.
5 */
6#ifdef __CHECKER__
7#undef __CHECKER__
8#warning "Sparse checking disabled for this file"
9#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070010
11#include <linux/kernel.h>
12#include <linux/fs.h>
13#include <linux/minix_fs.h>
14#include <linux/ext2_fs.h>
15#include <linux/romfs_fs.h>
16#include <linux/cramfs_fs.h>
17#include <linux/initrd.h>
18#include <linux/string.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090019#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
21#include "do_mounts.h"
Phillip Lougherb8fed872009-01-05 08:46:28 +000022#include "../fs/squashfs/squashfs_fs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
Alain Knaff30d65db2009-01-04 22:46:17 +010024#include <linux/decompress/generic.h>
25
Alain Knaff30d65db2009-01-04 22:46:17 +010026
Linus Torvalds1da177e2005-04-16 15:20:36 -070027int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */
28
29static int __init prompt_ramdisk(char *str)
30{
31 rd_prompt = simple_strtol(str,NULL,0) & 1;
32 return 1;
33}
34__setup("prompt_ramdisk=", prompt_ramdisk);
35
36int __initdata rd_image_start; /* starting block # of image */
37
38static int __init ramdisk_start_setup(char *str)
39{
40 rd_image_start = simple_strtol(str,NULL,0);
41 return 1;
42}
43__setup("ramdisk_start=", ramdisk_start_setup);
44
Alain Knaff30d65db2009-01-04 22:46:17 +010045static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47/*
48 * This routine tries to find a RAM disk image to load, and returns the
49 * number of blocks to read for a non-compressed image, 0 if the image
50 * is a compressed image, and -1 if an image with the right magic
51 * numbers could not be found.
52 *
53 * We currently check for the following magic numbers:
H. Peter Anvinb172fd82009-01-04 14:42:52 -080054 * minix
55 * ext2
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 * romfs
57 * cramfs
Phillip Lougherb8fed872009-01-05 08:46:28 +000058 * squashfs
H. Peter Anvinb172fd82009-01-04 14:42:52 -080059 * gzip
Linus Torvalds1da177e2005-04-16 15:20:36 -070060 */
H. Peter Anvinb172fd82009-01-04 14:42:52 -080061static int __init
Alain Knaff30d65db2009-01-04 22:46:17 +010062identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)
Linus Torvalds1da177e2005-04-16 15:20:36 -070063{
64 const int size = 512;
65 struct minix_super_block *minixsb;
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 struct romfs_super_block *romfsb;
67 struct cramfs_super *cramfsb;
Phillip Lougherb8fed872009-01-05 08:46:28 +000068 struct squashfs_super_block *squashfsb;
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 int nblocks = -1;
70 unsigned char *buf;
H. Peter Anvin889c92d2009-01-08 15:14:17 -080071 const char *compress_name;
Al Viro39429c52012-03-23 16:36:45 -040072 unsigned long n;
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74 buf = kmalloc(size, GFP_KERNEL);
Stephen Hemmingerc80544d2007-10-18 03:07:05 -070075 if (!buf)
Davidlohr Buesoea611b262011-03-22 16:34:49 -070076 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78 minixsb = (struct minix_super_block *) buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 romfsb = (struct romfs_super_block *) buf;
80 cramfsb = (struct cramfs_super *) buf;
Phillip Lougherb8fed872009-01-05 08:46:28 +000081 squashfsb = (struct squashfs_super_block *) buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 memset(buf, 0xe5, size);
83
84 /*
H. Peter Anvinb172fd82009-01-04 14:42:52 -080085 * Read block 0 to test for compressed kernel
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 */
87 sys_lseek(fd, start_block * BLOCK_SIZE, 0);
88 sys_read(fd, buf, size);
89
H. Peter Anvin889c92d2009-01-08 15:14:17 -080090 *decompressor = decompress_method(buf, size, &compress_name);
H. Peter Anvin23a22d52009-01-12 14:24:04 -080091 if (compress_name) {
H. Peter Anvin889c92d2009-01-08 15:14:17 -080092 printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
93 compress_name, start_block);
H. Peter Anvin23a22d52009-01-12 14:24:04 -080094 if (!*decompressor)
H. Peter Anvin73310a12009-01-14 11:28:35 -080095 printk(KERN_EMERG
96 "RAMDISK: %s decompressor not configured!\n",
H. Peter Anvin23a22d52009-01-12 14:24:04 -080097 compress_name);
H. Peter Anvin889c92d2009-01-08 15:14:17 -080098 nblocks = 0;
99 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100 }
101
102 /* romfs is at block zero too */
103 if (romfsb->word0 == ROMSB_WORD0 &&
104 romfsb->word1 == ROMSB_WORD1) {
105 printk(KERN_NOTICE
106 "RAMDISK: romfs filesystem found at block %d\n",
107 start_block);
108 nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
109 goto done;
110 }
111
112 if (cramfsb->magic == CRAMFS_MAGIC) {
113 printk(KERN_NOTICE
114 "RAMDISK: cramfs filesystem found at block %d\n",
115 start_block);
116 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
117 goto done;
118 }
119
Phillip Lougherb8fed872009-01-05 08:46:28 +0000120 /* squashfs is at block zero too */
121 if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) {
122 printk(KERN_NOTICE
123 "RAMDISK: squashfs filesystem found at block %d\n",
124 start_block);
125 nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1)
126 >> BLOCK_SIZE_BITS;
127 goto done;
128 }
129
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 /*
Neil Armstrongf919b922011-11-02 13:37:47 -0700131 * Read 512 bytes further to check if cramfs is padded
132 */
133 sys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0);
134 sys_read(fd, buf, size);
135
136 if (cramfsb->magic == CRAMFS_MAGIC) {
137 printk(KERN_NOTICE
138 "RAMDISK: cramfs filesystem found at block %d\n",
139 start_block);
140 nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
141 goto done;
142 }
143
144 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 * Read block 1 to test for minix and ext2 superblock
146 */
147 sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
148 sys_read(fd, buf, size);
149
150 /* Try minix */
151 if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
152 minixsb->s_magic == MINIX_SUPER_MAGIC2) {
153 printk(KERN_NOTICE
154 "RAMDISK: Minix filesystem found at block %d\n",
155 start_block);
156 nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
157 goto done;
158 }
159
160 /* Try ext2 */
Al Viro39429c52012-03-23 16:36:45 -0400161 n = ext2_image_size(buf);
162 if (n) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 printk(KERN_NOTICE
164 "RAMDISK: ext2 filesystem found at block %d\n",
165 start_block);
Al Viro39429c52012-03-23 16:36:45 -0400166 nblocks = n;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 goto done;
168 }
169
170 printk(KERN_NOTICE
171 "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
172 start_block);
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800173
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174done:
175 sys_lseek(fd, start_block * BLOCK_SIZE, 0);
176 kfree(buf);
177 return nblocks;
178}
179
180int __init rd_load_image(char *from)
181{
182 int res = 0;
183 int in_fd, out_fd;
184 unsigned long rd_blocks, devblocks;
185 int nblocks, i, disk;
186 char *buf = NULL;
187 unsigned short rotate = 0;
Alain Knaff30d65db2009-01-04 22:46:17 +0100188 decompress_fn decompressor = NULL;
Stephen Rothwellbc584502012-03-15 18:19:08 +0000189#if !defined(CONFIG_S390)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 char rotator[4] = { '|' , '/' , '-' , '\\' };
191#endif
192
H Hartley Sweetenc67e5382012-05-31 16:26:10 -0700193 out_fd = sys_open("/dev/ram", O_RDWR, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 if (out_fd < 0)
195 goto out;
196
197 in_fd = sys_open(from, O_RDONLY, 0);
198 if (in_fd < 0)
199 goto noclose_input;
200
Alain Knaff30d65db2009-01-04 22:46:17 +0100201 nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 if (nblocks < 0)
203 goto done;
204
205 if (nblocks == 0) {
Alain Knaff30d65db2009-01-04 22:46:17 +0100206 if (crd_load(in_fd, out_fd, decompressor) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 goto successful_load;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 goto done;
209 }
210
211 /*
212 * NOTE NOTE: nblocks is not actually blocks but
213 * the number of kibibytes of data to load into a ramdisk.
214 * So any ramdisk block size that is a multiple of 1KiB should
215 * work when the appropriate ramdisk_blocksize is specified
216 * on the command line.
217 *
218 * The default ramdisk_blocksize is 1KiB and it is generally
219 * silly to use anything else, so make sure to use 1KiB
220 * blocksize while generating ext2fs ramdisk-images.
221 */
222 if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
223 rd_blocks = 0;
224 else
225 rd_blocks >>= 1;
226
227 if (nblocks > rd_blocks) {
228 printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
229 nblocks, rd_blocks);
230 goto done;
231 }
H. Peter Anvinb172fd82009-01-04 14:42:52 -0800232
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 /*
234 * OK, time to copy in the data
235 */
236 if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
237 devblocks = 0;
238 else
239 devblocks >>= 1;
240
241 if (strcmp(from, "/initrd.image") == 0)
242 devblocks = nblocks;
243
244 if (devblocks == 0) {
245 printk(KERN_ERR "RAMDISK: could not determine device size\n");
246 goto done;
247 }
248
249 buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
Harvey Harrisond613c3e2008-04-28 14:13:14 -0700250 if (!buf) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
252 goto done;
253 }
254
255 printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
256 nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
257 for (i = 0, disk = 1; i < nblocks; i++) {
258 if (i && (i % devblocks == 0)) {
259 printk("done disk #%d.\n", disk++);
260 rotate = 0;
261 if (sys_close(in_fd)) {
262 printk("Error closing the disk.\n");
263 goto noclose_input;
264 }
265 change_floppy("disk #%d", disk);
266 in_fd = sys_open(from, O_RDONLY, 0);
267 if (in_fd < 0) {
268 printk("Error opening disk.\n");
269 goto noclose_input;
270 }
271 printk("Loading disk #%d... ", disk);
272 }
273 sys_read(in_fd, buf, BLOCK_SIZE);
274 sys_write(out_fd, buf, BLOCK_SIZE);
Stephen Rothwellbc584502012-03-15 18:19:08 +0000275#if !defined(CONFIG_S390)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 if (!(i % 16)) {
277 printk("%c\b", rotator[rotate & 0x3]);
278 rotate++;
279 }
280#endif
281 }
282 printk("done.\n");
283
284successful_load:
285 res = 1;
286done:
287 sys_close(in_fd);
288noclose_input:
289 sys_close(out_fd);
290out:
291 kfree(buf);
H Hartley Sweetenc67e5382012-05-31 16:26:10 -0700292 sys_unlink("/dev/ram");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 return res;
294}
295
296int __init rd_load_disk(int n)
297{
298 if (rd_prompt)
299 change_floppy("root floppy disk to be loaded into RAM disk");
Greg Kroah-Hartmanbdaf8522005-06-20 21:15:16 -0700300 create_dev("/dev/root", ROOT_DEV);
301 create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 return rd_load_image("/dev/root");
303}
304
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305static int exit_code;
Alain Knaff30d65db2009-01-04 22:46:17 +0100306static int decompress_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307static int crd_infd, crd_outfd;
308
Alain Knaff30d65db2009-01-04 22:46:17 +0100309static int __init compr_fill(void *buf, unsigned int len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310{
Alain Knaff30d65db2009-01-04 22:46:17 +0100311 int r = sys_read(crd_infd, buf, len);
312 if (r < 0)
313 printk(KERN_ERR "RAMDISK: error while reading compressed data");
314 else if (r == 0)
315 printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
316 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317}
318
Alain Knaff30d65db2009-01-04 22:46:17 +0100319static int __init compr_flush(void *window, unsigned int outcnt)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320{
Alain Knaff30d65db2009-01-04 22:46:17 +0100321 int written = sys_write(crd_outfd, window, outcnt);
322 if (written != outcnt) {
323 if (decompress_error == 0)
324 printk(KERN_ERR
325 "RAMDISK: incomplete write (%d != %d)\n",
326 written, outcnt);
327 decompress_error = 1;
328 return -1;
329 }
330 return outcnt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331}
332
333static void __init error(char *x)
334{
335 printk(KERN_ERR "%s\n", x);
336 exit_code = 1;
Alain Knaff30d65db2009-01-04 22:46:17 +0100337 decompress_error = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338}
339
Alain Knaff30d65db2009-01-04 22:46:17 +0100340static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341{
342 int result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 crd_infd = in_fd;
344 crd_outfd = out_fd;
Alain Knaff30d65db2009-01-04 22:46:17 +0100345 result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
346 if (decompress_error)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700347 result = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 return result;
349}