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v3.1
 
 
 
 
 
 
 
 
 
 
  1
  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>
 10#include <linux/slab.h>
 11
 12#include "do_mounts.h"
 13#include "../fs/squashfs/squashfs_fs.h"
 14
 15#include <linux/decompress/generic.h>
 16
 17
 18int __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
 36static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);
 37
 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:
 45 *	minix
 46 *	ext2
 47 *	romfs
 48 *	cramfs
 49 *	squashfs
 50 *	gzip
 
 
 
 
 
 51 */
 52static int __init
 53identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)
 54{
 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;
 60	struct squashfs_super_block *squashfsb;
 61	int nblocks = -1;
 62	unsigned char *buf;
 63	const char *compress_name;
 
 64
 65	buf = kmalloc(size, GFP_KERNEL);
 66	if (!buf)
 67		return -ENOMEM;
 68
 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;
 73	squashfsb = (struct squashfs_super_block *) buf;
 74	memset(buf, 0xe5, size);
 75
 76	/*
 77	 * Read block 0 to test for compressed kernel
 78	 */
 79	sys_lseek(fd, start_block * BLOCK_SIZE, 0);
 80	sys_read(fd, buf, size);
 81
 82	*decompressor = decompress_method(buf, size, &compress_name);
 83	if (compress_name) {
 84		printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
 85		       compress_name, start_block);
 86		if (!*decompressor)
 87			printk(KERN_EMERG
 88			       "RAMDISK: %s decompressor not configured!\n",
 89			       compress_name);
 90		nblocks = 0;
 91		goto done;
 92	}
 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
112	/* 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
122	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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);
151
152done:
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;
166	decompress_fn decompressor = NULL;
167#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
168	char rotator[4] = { '|' , '/' , '-' , '\\' };
169#endif
170
171	out_fd = sys_open((const char __user __force *) "/dev/ram", O_RDWR, 0);
172	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
179	nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
180	if (nblocks < 0)
181		goto done;
182
183	if (nblocks == 0) {
184		if (crd_load(in_fd, out_fd, decompressor) == 0)
185			goto successful_load;
186		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	}
210
211	/*
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);
228	if (!buf) {
229		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);
253#if !defined(CONFIG_S390) && !defined(CONFIG_PPC_ISERIES)
254		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);
270	sys_unlink((const char __user __force *) "/dev/ram");
271	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");
278	create_dev("/dev/root", ROOT_DEV);
279	create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
280	return rd_load_image("/dev/root");
281}
282
283static int exit_code;
284static int decompress_error;
285static int crd_infd, crd_outfd;
286
287static int __init compr_fill(void *buf, unsigned int len)
288{
289	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;
295}
296
297static int __init compr_flush(void *window, unsigned int outcnt)
298{
299	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;
309}
310
311static void __init error(char *x)
312{
313	printk(KERN_ERR "%s\n", x);
314	exit_code = 1;
315	decompress_error = 1;
316}
317
318static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
319{
320	int result;
321	crd_infd = in_fd;
322	crd_outfd = out_fd;
 
 
 
 
 
 
 
323	result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
324	if (decompress_error)
325		result = 1;
326	return result;
327}
v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Many of the syscalls used in this file expect some of the arguments
  4 * to be __user pointers not __kernel pointers.  To limit the sparse
  5 * noise, turn off sparse checking for this file.
  6 */
  7#ifdef __CHECKER__
  8#undef __CHECKER__
  9#warning "Sparse checking disabled for this file"
 10#endif
 11
 12#include <linux/kernel.h>
 13#include <linux/fs.h>
 14#include <linux/minix_fs.h>
 15#include <linux/ext2_fs.h>
 16#include <linux/romfs_fs.h>
 17#include <uapi/linux/cramfs_fs.h>
 18#include <linux/initrd.h>
 19#include <linux/string.h>
 20#include <linux/slab.h>
 21
 22#include "do_mounts.h"
 23#include "../fs/squashfs/squashfs_fs.h"
 24
 25#include <linux/decompress/generic.h>
 26
 27
 28int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */
 29
 30static int __init prompt_ramdisk(char *str)
 31{
 32	rd_prompt = simple_strtol(str,NULL,0) & 1;
 33	return 1;
 34}
 35__setup("prompt_ramdisk=", prompt_ramdisk);
 36
 37int __initdata rd_image_start;		/* starting block # of image */
 38
 39static int __init ramdisk_start_setup(char *str)
 40{
 41	rd_image_start = simple_strtol(str,NULL,0);
 42	return 1;
 43}
 44__setup("ramdisk_start=", ramdisk_start_setup);
 45
 46static int __init crd_load(int in_fd, int out_fd, decompress_fn deco);
 47
 48/*
 49 * This routine tries to find a RAM disk image to load, and returns the
 50 * number of blocks to read for a non-compressed image, 0 if the image
 51 * is a compressed image, and -1 if an image with the right magic
 52 * numbers could not be found.
 53 *
 54 * We currently check for the following magic numbers:
 55 *	minix
 56 *	ext2
 57 *	romfs
 58 *	cramfs
 59 *	squashfs
 60 *	gzip
 61 *	bzip2
 62 *	lzma
 63 *	xz
 64 *	lzo
 65 *	lz4
 66 */
 67static int __init
 68identify_ramdisk_image(int fd, int start_block, decompress_fn *decompressor)
 69{
 70	const int size = 512;
 71	struct minix_super_block *minixsb;
 
 72	struct romfs_super_block *romfsb;
 73	struct cramfs_super *cramfsb;
 74	struct squashfs_super_block *squashfsb;
 75	int nblocks = -1;
 76	unsigned char *buf;
 77	const char *compress_name;
 78	unsigned long n;
 79
 80	buf = kmalloc(size, GFP_KERNEL);
 81	if (!buf)
 82		return -ENOMEM;
 83
 84	minixsb = (struct minix_super_block *) buf;
 
 85	romfsb = (struct romfs_super_block *) buf;
 86	cramfsb = (struct cramfs_super *) buf;
 87	squashfsb = (struct squashfs_super_block *) buf;
 88	memset(buf, 0xe5, size);
 89
 90	/*
 91	 * Read block 0 to test for compressed kernel
 92	 */
 93	ksys_lseek(fd, start_block * BLOCK_SIZE, 0);
 94	ksys_read(fd, buf, size);
 95
 96	*decompressor = decompress_method(buf, size, &compress_name);
 97	if (compress_name) {
 98		printk(KERN_NOTICE "RAMDISK: %s image found at block %d\n",
 99		       compress_name, start_block);
100		if (!*decompressor)
101			printk(KERN_EMERG
102			       "RAMDISK: %s decompressor not configured!\n",
103			       compress_name);
104		nblocks = 0;
105		goto done;
106	}
107
108	/* romfs is at block zero too */
109	if (romfsb->word0 == ROMSB_WORD0 &&
110	    romfsb->word1 == ROMSB_WORD1) {
111		printk(KERN_NOTICE
112		       "RAMDISK: romfs filesystem found at block %d\n",
113		       start_block);
114		nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
115		goto done;
116	}
117
118	if (cramfsb->magic == CRAMFS_MAGIC) {
119		printk(KERN_NOTICE
120		       "RAMDISK: cramfs filesystem found at block %d\n",
121		       start_block);
122		nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
123		goto done;
124	}
125
126	/* squashfs is at block zero too */
127	if (le32_to_cpu(squashfsb->s_magic) == SQUASHFS_MAGIC) {
128		printk(KERN_NOTICE
129		       "RAMDISK: squashfs filesystem found at block %d\n",
130		       start_block);
131		nblocks = (le64_to_cpu(squashfsb->bytes_used) + BLOCK_SIZE - 1)
132			 >> BLOCK_SIZE_BITS;
133		goto done;
134	}
135
136	/*
137	 * Read 512 bytes further to check if cramfs is padded
138	 */
139	ksys_lseek(fd, start_block * BLOCK_SIZE + 0x200, 0);
140	ksys_read(fd, buf, size);
141
142	if (cramfsb->magic == CRAMFS_MAGIC) {
143		printk(KERN_NOTICE
144		       "RAMDISK: cramfs filesystem found at block %d\n",
145		       start_block);
146		nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
147		goto done;
148	}
149
150	/*
151	 * Read block 1 to test for minix and ext2 superblock
152	 */
153	ksys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
154	ksys_read(fd, buf, size);
155
156	/* Try minix */
157	if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
158	    minixsb->s_magic == MINIX_SUPER_MAGIC2) {
159		printk(KERN_NOTICE
160		       "RAMDISK: Minix filesystem found at block %d\n",
161		       start_block);
162		nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
163		goto done;
164	}
165
166	/* Try ext2 */
167	n = ext2_image_size(buf);
168	if (n) {
169		printk(KERN_NOTICE
170		       "RAMDISK: ext2 filesystem found at block %d\n",
171		       start_block);
172		nblocks = n;
 
173		goto done;
174	}
175
176	printk(KERN_NOTICE
177	       "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
178	       start_block);
179
180done:
181	ksys_lseek(fd, start_block * BLOCK_SIZE, 0);
182	kfree(buf);
183	return nblocks;
184}
185
186int __init rd_load_image(char *from)
187{
188	int res = 0;
189	int in_fd, out_fd;
190	unsigned long rd_blocks, devblocks;
191	int nblocks, i, disk;
192	char *buf = NULL;
193	unsigned short rotate = 0;
194	decompress_fn decompressor = NULL;
195#if !defined(CONFIG_S390)
196	char rotator[4] = { '|' , '/' , '-' , '\\' };
197#endif
198
199	out_fd = ksys_open("/dev/ram", O_RDWR, 0);
200	if (out_fd < 0)
201		goto out;
202
203	in_fd = ksys_open(from, O_RDONLY, 0);
204	if (in_fd < 0)
205		goto noclose_input;
206
207	nblocks = identify_ramdisk_image(in_fd, rd_image_start, &decompressor);
208	if (nblocks < 0)
209		goto done;
210
211	if (nblocks == 0) {
212		if (crd_load(in_fd, out_fd, decompressor) == 0)
213			goto successful_load;
214		goto done;
215	}
216
217	/*
218	 * NOTE NOTE: nblocks is not actually blocks but
219	 * the number of kibibytes of data to load into a ramdisk.
 
 
 
 
 
 
 
220	 */
221	if (ksys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
222		rd_blocks = 0;
223	else
224		rd_blocks >>= 1;
225
226	if (nblocks > rd_blocks) {
227		printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
228		       nblocks, rd_blocks);
229		goto done;
230	}
231
232	/*
233	 * OK, time to copy in the data
234	 */
235	if (ksys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
236		devblocks = 0;
237	else
238		devblocks >>= 1;
239
240	if (strcmp(from, "/initrd.image") == 0)
241		devblocks = nblocks;
242
243	if (devblocks == 0) {
244		printk(KERN_ERR "RAMDISK: could not determine device size\n");
245		goto done;
246	}
247
248	buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
249	if (!buf) {
250		printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
251		goto done;
252	}
253
254	printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
255		nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
256	for (i = 0, disk = 1; i < nblocks; i++) {
257		if (i && (i % devblocks == 0)) {
258			pr_cont("done disk #%d.\n", disk++);
259			rotate = 0;
260			if (ksys_close(in_fd)) {
261				printk("Error closing the disk.\n");
262				goto noclose_input;
263			}
264			change_floppy("disk #%d", disk);
265			in_fd = ksys_open(from, O_RDONLY, 0);
266			if (in_fd < 0)  {
267				printk("Error opening disk.\n");
268				goto noclose_input;
269			}
270			printk("Loading disk #%d... ", disk);
271		}
272		ksys_read(in_fd, buf, BLOCK_SIZE);
273		ksys_write(out_fd, buf, BLOCK_SIZE);
274#if !defined(CONFIG_S390)
275		if (!(i % 16)) {
276			pr_cont("%c\b", rotator[rotate & 0x3]);
277			rotate++;
278		}
279#endif
280	}
281	pr_cont("done.\n");
282
283successful_load:
284	res = 1;
285done:
286	ksys_close(in_fd);
287noclose_input:
288	ksys_close(out_fd);
289out:
290	kfree(buf);
291	ksys_unlink("/dev/ram");
292	return res;
293}
294
295int __init rd_load_disk(int n)
296{
297	if (rd_prompt)
298		change_floppy("root floppy disk to be loaded into RAM disk");
299	create_dev("/dev/root", ROOT_DEV);
300	create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n));
301	return rd_load_image("/dev/root");
302}
303
304static int exit_code;
305static int decompress_error;
306static int crd_infd, crd_outfd;
307
308static long __init compr_fill(void *buf, unsigned long len)
309{
310	long r = ksys_read(crd_infd, buf, len);
311	if (r < 0)
312		printk(KERN_ERR "RAMDISK: error while reading compressed data");
313	else if (r == 0)
314		printk(KERN_ERR "RAMDISK: EOF while reading compressed data");
315	return r;
316}
317
318static long __init compr_flush(void *window, unsigned long outcnt)
319{
320	long written = ksys_write(crd_outfd, window, outcnt);
321	if (written != outcnt) {
322		if (decompress_error == 0)
323			printk(KERN_ERR
324			       "RAMDISK: incomplete write (%ld != %ld)\n",
325			       written, outcnt);
326		decompress_error = 1;
327		return -1;
328	}
329	return outcnt;
330}
331
332static void __init error(char *x)
333{
334	printk(KERN_ERR "%s\n", x);
335	exit_code = 1;
336	decompress_error = 1;
337}
338
339static int __init crd_load(int in_fd, int out_fd, decompress_fn deco)
340{
341	int result;
342	crd_infd = in_fd;
343	crd_outfd = out_fd;
344
345	if (!deco) {
346		pr_emerg("Invalid ramdisk decompression routine.  "
347			 "Select appropriate config option.\n");
348		panic("Could not decompress initial ramdisk image.");
349	}
350
351	result = deco(NULL, 0, compr_fill, compr_flush, NULL, NULL, error);
352	if (decompress_error)
353		result = 1;
354	return result;
355}