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-rw-r--r--init/do_mounts_rd.c429
1 files changed, 429 insertions, 0 deletions
diff --git a/init/do_mounts_rd.c b/init/do_mounts_rd.c
new file mode 100644
index 00000000000..c10b08a8098
--- /dev/null
+++ b/init/do_mounts_rd.c
@@ -0,0 +1,429 @@
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/minix_fs.h>
+#include <linux/ext2_fs.h>
+#include <linux/romfs_fs.h>
+#include <linux/cramfs_fs.h>
+#include <linux/initrd.h>
+#include <linux/string.h>
+
+#include "do_mounts.h"
+
+#define BUILD_CRAMDISK
+
+int __initdata rd_prompt = 1;/* 1 = prompt for RAM disk, 0 = don't prompt */
+
+static int __init prompt_ramdisk(char *str)
+{
+ rd_prompt = simple_strtol(str,NULL,0) & 1;
+ return 1;
+}
+__setup("prompt_ramdisk=", prompt_ramdisk);
+
+int __initdata rd_image_start; /* starting block # of image */
+
+static int __init ramdisk_start_setup(char *str)
+{
+ rd_image_start = simple_strtol(str,NULL,0);
+ return 1;
+}
+__setup("ramdisk_start=", ramdisk_start_setup);
+
+static int __init crd_load(int in_fd, int out_fd);
+
+/*
+ * This routine tries to find a RAM disk image to load, and returns the
+ * number of blocks to read for a non-compressed image, 0 if the image
+ * is a compressed image, and -1 if an image with the right magic
+ * numbers could not be found.
+ *
+ * We currently check for the following magic numbers:
+ * minix
+ * ext2
+ * romfs
+ * cramfs
+ * gzip
+ */
+static int __init
+identify_ramdisk_image(int fd, int start_block)
+{
+ const int size = 512;
+ struct minix_super_block *minixsb;
+ struct ext2_super_block *ext2sb;
+ struct romfs_super_block *romfsb;
+ struct cramfs_super *cramfsb;
+ int nblocks = -1;
+ unsigned char *buf;
+
+ buf = kmalloc(size, GFP_KERNEL);
+ if (buf == 0)
+ return -1;
+
+ minixsb = (struct minix_super_block *) buf;
+ ext2sb = (struct ext2_super_block *) buf;
+ romfsb = (struct romfs_super_block *) buf;
+ cramfsb = (struct cramfs_super *) buf;
+ memset(buf, 0xe5, size);
+
+ /*
+ * Read block 0 to test for gzipped kernel
+ */
+ sys_lseek(fd, start_block * BLOCK_SIZE, 0);
+ sys_read(fd, buf, size);
+
+ /*
+ * If it matches the gzip magic numbers, return -1
+ */
+ if (buf[0] == 037 && ((buf[1] == 0213) || (buf[1] == 0236))) {
+ printk(KERN_NOTICE
+ "RAMDISK: Compressed image found at block %d\n",
+ start_block);
+ nblocks = 0;
+ goto done;
+ }
+
+ /* romfs is at block zero too */
+ if (romfsb->word0 == ROMSB_WORD0 &&
+ romfsb->word1 == ROMSB_WORD1) {
+ printk(KERN_NOTICE
+ "RAMDISK: romfs filesystem found at block %d\n",
+ start_block);
+ nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
+ goto done;
+ }
+
+ if (cramfsb->magic == CRAMFS_MAGIC) {
+ printk(KERN_NOTICE
+ "RAMDISK: cramfs filesystem found at block %d\n",
+ start_block);
+ nblocks = (cramfsb->size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
+ goto done;
+ }
+
+ /*
+ * Read block 1 to test for minix and ext2 superblock
+ */
+ sys_lseek(fd, (start_block+1) * BLOCK_SIZE, 0);
+ sys_read(fd, buf, size);
+
+ /* Try minix */
+ if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
+ minixsb->s_magic == MINIX_SUPER_MAGIC2) {
+ printk(KERN_NOTICE
+ "RAMDISK: Minix filesystem found at block %d\n",
+ start_block);
+ nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
+ goto done;
+ }
+
+ /* Try ext2 */
+ if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) {
+ printk(KERN_NOTICE
+ "RAMDISK: ext2 filesystem found at block %d\n",
+ start_block);
+ nblocks = le32_to_cpu(ext2sb->s_blocks_count) <<
+ le32_to_cpu(ext2sb->s_log_block_size);
+ goto done;
+ }
+
+ printk(KERN_NOTICE
+ "RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
+ start_block);
+
+done:
+ sys_lseek(fd, start_block * BLOCK_SIZE, 0);
+ kfree(buf);
+ return nblocks;
+}
+
+int __init rd_load_image(char *from)
+{
+ int res = 0;
+ int in_fd, out_fd;
+ unsigned long rd_blocks, devblocks;
+ int nblocks, i, disk;
+ char *buf = NULL;
+ unsigned short rotate = 0;
+#if !defined(CONFIG_ARCH_S390) && !defined(CONFIG_PPC_ISERIES)
+ char rotator[4] = { '|' , '/' , '-' , '\\' };
+#endif
+
+ out_fd = sys_open("/dev/ram", O_RDWR, 0);
+ if (out_fd < 0)
+ goto out;
+
+ in_fd = sys_open(from, O_RDONLY, 0);
+ if (in_fd < 0)
+ goto noclose_input;
+
+ nblocks = identify_ramdisk_image(in_fd, rd_image_start);
+ if (nblocks < 0)
+ goto done;
+
+ if (nblocks == 0) {
+#ifdef BUILD_CRAMDISK
+ if (crd_load(in_fd, out_fd) == 0)
+ goto successful_load;
+#else
+ printk(KERN_NOTICE
+ "RAMDISK: Kernel does not support compressed "
+ "RAM disk images\n");
+#endif
+ goto done;
+ }
+
+ /*
+ * NOTE NOTE: nblocks is not actually blocks but
+ * the number of kibibytes of data to load into a ramdisk.
+ * So any ramdisk block size that is a multiple of 1KiB should
+ * work when the appropriate ramdisk_blocksize is specified
+ * on the command line.
+ *
+ * The default ramdisk_blocksize is 1KiB and it is generally
+ * silly to use anything else, so make sure to use 1KiB
+ * blocksize while generating ext2fs ramdisk-images.
+ */
+ if (sys_ioctl(out_fd, BLKGETSIZE, (unsigned long)&rd_blocks) < 0)
+ rd_blocks = 0;
+ else
+ rd_blocks >>= 1;
+
+ if (nblocks > rd_blocks) {
+ printk("RAMDISK: image too big! (%dKiB/%ldKiB)\n",
+ nblocks, rd_blocks);
+ goto done;
+ }
+
+ /*
+ * OK, time to copy in the data
+ */
+ if (sys_ioctl(in_fd, BLKGETSIZE, (unsigned long)&devblocks) < 0)
+ devblocks = 0;
+ else
+ devblocks >>= 1;
+
+ if (strcmp(from, "/initrd.image") == 0)
+ devblocks = nblocks;
+
+ if (devblocks == 0) {
+ printk(KERN_ERR "RAMDISK: could not determine device size\n");
+ goto done;
+ }
+
+ buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
+ if (buf == 0) {
+ printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
+ goto done;
+ }
+
+ printk(KERN_NOTICE "RAMDISK: Loading %dKiB [%ld disk%s] into ram disk... ",
+ nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
+ for (i = 0, disk = 1; i < nblocks; i++) {
+ if (i && (i % devblocks == 0)) {
+ printk("done disk #%d.\n", disk++);
+ rotate = 0;
+ if (sys_close(in_fd)) {
+ printk("Error closing the disk.\n");
+ goto noclose_input;
+ }
+ change_floppy("disk #%d", disk);
+ in_fd = sys_open(from, O_RDONLY, 0);
+ if (in_fd < 0) {
+ printk("Error opening disk.\n");
+ goto noclose_input;
+ }
+ printk("Loading disk #%d... ", disk);
+ }
+ sys_read(in_fd, buf, BLOCK_SIZE);
+ sys_write(out_fd, buf, BLOCK_SIZE);
+#if !defined(CONFIG_ARCH_S390) && !defined(CONFIG_PPC_ISERIES)
+ if (!(i % 16)) {
+ printk("%c\b", rotator[rotate & 0x3]);
+ rotate++;
+ }
+#endif
+ }
+ printk("done.\n");
+
+successful_load:
+ res = 1;
+done:
+ sys_close(in_fd);
+noclose_input:
+ sys_close(out_fd);
+out:
+ kfree(buf);
+ sys_unlink("/dev/ram");
+ return res;
+}
+
+int __init rd_load_disk(int n)
+{
+ if (rd_prompt)
+ change_floppy("root floppy disk to be loaded into RAM disk");
+ create_dev("/dev/root", ROOT_DEV, root_device_name);
+ create_dev("/dev/ram", MKDEV(RAMDISK_MAJOR, n), NULL);
+ return rd_load_image("/dev/root");
+}
+
+#ifdef BUILD_CRAMDISK
+
+/*
+ * gzip declarations
+ */
+
+#define OF(args) args
+
+#ifndef memzero
+#define memzero(s, n) memset ((s), 0, (n))
+#endif
+
+typedef unsigned char uch;
+typedef unsigned short ush;
+typedef unsigned long ulg;
+
+#define INBUFSIZ 4096
+#define WSIZE 0x8000 /* window size--must be a power of two, and */
+ /* at least 32K for zip's deflate method */
+
+static uch *inbuf;
+static uch *window;
+
+static unsigned insize; /* valid bytes in inbuf */
+static unsigned inptr; /* index of next byte to be processed in inbuf */
+static unsigned outcnt; /* bytes in output buffer */
+static int exit_code;
+static int unzip_error;
+static long bytes_out;
+static int crd_infd, crd_outfd;
+
+#define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf())
+
+/* Diagnostic functions (stubbed out) */
+#define Assert(cond,msg)
+#define Trace(x)
+#define Tracev(x)
+#define Tracevv(x)
+#define Tracec(c,x)
+#define Tracecv(c,x)
+
+#define STATIC static
+#define INIT __init
+
+static int __init fill_inbuf(void);
+static void __init flush_window(void);
+static void __init *malloc(size_t size);
+static void __init free(void *where);
+static void __init error(char *m);
+static void __init gzip_mark(void **);
+static void __init gzip_release(void **);
+
+#include "../lib/inflate.c"
+
+static void __init *malloc(size_t size)
+{
+ return kmalloc(size, GFP_KERNEL);
+}
+
+static void __init free(void *where)
+{
+ kfree(where);
+}
+
+static void __init gzip_mark(void **ptr)
+{
+}
+
+static void __init gzip_release(void **ptr)
+{
+}
+
+
+/* ===========================================================================
+ * Fill the input buffer. This is called only when the buffer is empty
+ * and at least one byte is really needed.
+ * Returning -1 does not guarantee that gunzip() will ever return.
+ */
+static int __init fill_inbuf(void)
+{
+ if (exit_code) return -1;
+
+ insize = sys_read(crd_infd, inbuf, INBUFSIZ);
+ if (insize == 0) {
+ error("RAMDISK: ran out of compressed data");
+ return -1;
+ }
+
+ inptr = 1;
+
+ return inbuf[0];
+}
+
+/* ===========================================================================
+ * Write the output window window[0..outcnt-1] and update crc and bytes_out.
+ * (Used for the decompressed data only.)
+ */
+static void __init flush_window(void)
+{
+ ulg c = crc; /* temporary variable */
+ unsigned n, written;
+ uch *in, ch;
+
+ written = sys_write(crd_outfd, window, outcnt);
+ if (written != outcnt && unzip_error == 0) {
+ printk(KERN_ERR "RAMDISK: incomplete write (%d != %d) %ld\n",
+ written, outcnt, bytes_out);
+ unzip_error = 1;
+ }
+ in = window;
+ for (n = 0; n < outcnt; n++) {
+ ch = *in++;
+ c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
+ }
+ crc = c;
+ bytes_out += (ulg)outcnt;
+ outcnt = 0;
+}
+
+static void __init error(char *x)
+{
+ printk(KERN_ERR "%s\n", x);
+ exit_code = 1;
+ unzip_error = 1;
+}
+
+static int __init crd_load(int in_fd, int out_fd)
+{
+ int result;
+
+ insize = 0; /* valid bytes in inbuf */
+ inptr = 0; /* index of next byte to be processed in inbuf */
+ outcnt = 0; /* bytes in output buffer */
+ exit_code = 0;
+ bytes_out = 0;
+ crc = (ulg)0xffffffffL; /* shift register contents */
+
+ crd_infd = in_fd;
+ crd_outfd = out_fd;
+ inbuf = kmalloc(INBUFSIZ, GFP_KERNEL);
+ if (inbuf == 0) {
+ printk(KERN_ERR "RAMDISK: Couldn't allocate gzip buffer\n");
+ return -1;
+ }
+ window = kmalloc(WSIZE, GFP_KERNEL);
+ if (window == 0) {
+ printk(KERN_ERR "RAMDISK: Couldn't allocate gzip window\n");
+ kfree(inbuf);
+ return -1;
+ }
+ makecrc();
+ result = gunzip();
+ if (unzip_error)
+ result = 1;
+ kfree(inbuf);
+ kfree(window);
+ return result;
+}
+
+#endif /* BUILD_CRAMDISK */
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