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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /init/initramfs.c
downloadlinux-linaro-stable-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'init/initramfs.c')
-rw-r--r--init/initramfs.c500
1 files changed, 500 insertions, 0 deletions
diff --git a/init/initramfs.c b/init/initramfs.c
new file mode 100644
index 000000000000..02c5ce64990d
--- /dev/null
+++ b/init/initramfs.c
@@ -0,0 +1,500 @@
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/syscalls.h>
+
+static __initdata char *message;
+static void __init error(char *x)
+{
+ if (!message)
+ message = x;
+}
+
+static void __init *malloc(size_t size)
+{
+ return kmalloc(size, GFP_KERNEL);
+}
+
+static void __init free(void *where)
+{
+ kfree(where);
+}
+
+/* link hash */
+
+static __initdata struct hash {
+ int ino, minor, major;
+ struct hash *next;
+ char *name;
+} *head[32];
+
+static inline int hash(int major, int minor, int ino)
+{
+ unsigned long tmp = ino + minor + (major << 3);
+ tmp += tmp >> 5;
+ return tmp & 31;
+}
+
+static char __init *find_link(int major, int minor, int ino, char *name)
+{
+ struct hash **p, *q;
+ for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
+ if ((*p)->ino != ino)
+ continue;
+ if ((*p)->minor != minor)
+ continue;
+ if ((*p)->major != major)
+ continue;
+ return (*p)->name;
+ }
+ q = (struct hash *)malloc(sizeof(struct hash));
+ if (!q)
+ panic("can't allocate link hash entry");
+ q->ino = ino;
+ q->minor = minor;
+ q->major = major;
+ q->name = name;
+ q->next = NULL;
+ *p = q;
+ return NULL;
+}
+
+static void __init free_hash(void)
+{
+ struct hash **p, *q;
+ for (p = head; p < head + 32; p++) {
+ while (*p) {
+ q = *p;
+ *p = q->next;
+ free(q);
+ }
+ }
+}
+
+/* cpio header parsing */
+
+static __initdata unsigned long ino, major, minor, nlink;
+static __initdata mode_t mode;
+static __initdata unsigned long body_len, name_len;
+static __initdata uid_t uid;
+static __initdata gid_t gid;
+static __initdata unsigned rdev;
+
+static void __init parse_header(char *s)
+{
+ unsigned long parsed[12];
+ char buf[9];
+ int i;
+
+ buf[8] = '\0';
+ for (i = 0, s += 6; i < 12; i++, s += 8) {
+ memcpy(buf, s, 8);
+ parsed[i] = simple_strtoul(buf, NULL, 16);
+ }
+ ino = parsed[0];
+ mode = parsed[1];
+ uid = parsed[2];
+ gid = parsed[3];
+ nlink = parsed[4];
+ body_len = parsed[6];
+ major = parsed[7];
+ minor = parsed[8];
+ rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
+ name_len = parsed[11];
+}
+
+/* FSM */
+
+static __initdata enum state {
+ Start,
+ Collect,
+ GotHeader,
+ SkipIt,
+ GotName,
+ CopyFile,
+ GotSymlink,
+ Reset
+} state, next_state;
+
+static __initdata char *victim;
+static __initdata unsigned count;
+static __initdata loff_t this_header, next_header;
+
+static __initdata int dry_run;
+
+static inline void eat(unsigned n)
+{
+ victim += n;
+ this_header += n;
+ count -= n;
+}
+
+#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
+
+static __initdata char *collected;
+static __initdata int remains;
+static __initdata char *collect;
+
+static void __init read_into(char *buf, unsigned size, enum state next)
+{
+ if (count >= size) {
+ collected = victim;
+ eat(size);
+ state = next;
+ } else {
+ collect = collected = buf;
+ remains = size;
+ next_state = next;
+ state = Collect;
+ }
+}
+
+static __initdata char *header_buf, *symlink_buf, *name_buf;
+
+static int __init do_start(void)
+{
+ read_into(header_buf, 110, GotHeader);
+ return 0;
+}
+
+static int __init do_collect(void)
+{
+ unsigned n = remains;
+ if (count < n)
+ n = count;
+ memcpy(collect, victim, n);
+ eat(n);
+ collect += n;
+ if ((remains -= n) != 0)
+ return 1;
+ state = next_state;
+ return 0;
+}
+
+static int __init do_header(void)
+{
+ if (memcmp(collected, "070701", 6)) {
+ error("no cpio magic");
+ return 1;
+ }
+ parse_header(collected);
+ next_header = this_header + N_ALIGN(name_len) + body_len;
+ next_header = (next_header + 3) & ~3;
+ if (dry_run) {
+ read_into(name_buf, N_ALIGN(name_len), GotName);
+ return 0;
+ }
+ state = SkipIt;
+ if (name_len <= 0 || name_len > PATH_MAX)
+ return 0;
+ if (S_ISLNK(mode)) {
+ if (body_len > PATH_MAX)
+ return 0;
+ collect = collected = symlink_buf;
+ remains = N_ALIGN(name_len) + body_len;
+ next_state = GotSymlink;
+ state = Collect;
+ return 0;
+ }
+ if (S_ISREG(mode) || !body_len)
+ read_into(name_buf, N_ALIGN(name_len), GotName);
+ return 0;
+}
+
+static int __init do_skip(void)
+{
+ if (this_header + count < next_header) {
+ eat(count);
+ return 1;
+ } else {
+ eat(next_header - this_header);
+ state = next_state;
+ return 0;
+ }
+}
+
+static int __init do_reset(void)
+{
+ while(count && *victim == '\0')
+ eat(1);
+ if (count && (this_header & 3))
+ error("broken padding");
+ return 1;
+}
+
+static int __init maybe_link(void)
+{
+ if (nlink >= 2) {
+ char *old = find_link(major, minor, ino, collected);
+ if (old)
+ return (sys_link(old, collected) < 0) ? -1 : 1;
+ }
+ return 0;
+}
+
+static __initdata int wfd;
+
+static int __init do_name(void)
+{
+ state = SkipIt;
+ next_state = Reset;
+ if (strcmp(collected, "TRAILER!!!") == 0) {
+ free_hash();
+ return 0;
+ }
+ if (dry_run)
+ return 0;
+ if (S_ISREG(mode)) {
+ if (maybe_link() >= 0) {
+ wfd = sys_open(collected, O_WRONLY|O_CREAT, mode);
+ if (wfd >= 0) {
+ sys_fchown(wfd, uid, gid);
+ sys_fchmod(wfd, mode);
+ state = CopyFile;
+ }
+ }
+ } else if (S_ISDIR(mode)) {
+ sys_mkdir(collected, mode);
+ sys_chown(collected, uid, gid);
+ sys_chmod(collected, mode);
+ } else if (S_ISBLK(mode) || S_ISCHR(mode) ||
+ S_ISFIFO(mode) || S_ISSOCK(mode)) {
+ if (maybe_link() == 0) {
+ sys_mknod(collected, mode, rdev);
+ sys_chown(collected, uid, gid);
+ sys_chmod(collected, mode);
+ }
+ }
+ return 0;
+}
+
+static int __init do_copy(void)
+{
+ if (count >= body_len) {
+ sys_write(wfd, victim, body_len);
+ sys_close(wfd);
+ eat(body_len);
+ state = SkipIt;
+ return 0;
+ } else {
+ sys_write(wfd, victim, count);
+ body_len -= count;
+ eat(count);
+ return 1;
+ }
+}
+
+static int __init do_symlink(void)
+{
+ collected[N_ALIGN(name_len) + body_len] = '\0';
+ sys_symlink(collected + N_ALIGN(name_len), collected);
+ sys_lchown(collected, uid, gid);
+ state = SkipIt;
+ next_state = Reset;
+ return 0;
+}
+
+static __initdata int (*actions[])(void) = {
+ [Start] = do_start,
+ [Collect] = do_collect,
+ [GotHeader] = do_header,
+ [SkipIt] = do_skip,
+ [GotName] = do_name,
+ [CopyFile] = do_copy,
+ [GotSymlink] = do_symlink,
+ [Reset] = do_reset,
+};
+
+static int __init write_buffer(char *buf, unsigned len)
+{
+ count = len;
+ victim = buf;
+
+ while (!actions[state]())
+ ;
+ return len - count;
+}
+
+static void __init flush_buffer(char *buf, unsigned len)
+{
+ int written;
+ if (message)
+ return;
+ while ((written = write_buffer(buf, len)) < len && !message) {
+ char c = buf[written];
+ if (c == '0') {
+ buf += written;
+ len -= written;
+ state = Start;
+ } else if (c == 0) {
+ buf += written;
+ len -= written;
+ state = Reset;
+ } else
+ error("junk in compressed archive");
+ }
+}
+
+/*
+ * 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 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 long bytes_out;
+
+#define get_byte() (inptr < insize ? inbuf[inptr++] : -1)
+
+/* 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 void __init flush_window(void);
+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 gzip_mark(void **ptr)
+{
+}
+
+static void __init gzip_release(void **ptr)
+{
+}
+
+/* ===========================================================================
+ * 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;
+ uch *in, ch;
+
+ flush_buffer(window, outcnt);
+ 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 char * __init unpack_to_rootfs(char *buf, unsigned len, int check_only)
+{
+ int written;
+ dry_run = check_only;
+ header_buf = malloc(110);
+ symlink_buf = malloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1);
+ name_buf = malloc(N_ALIGN(PATH_MAX));
+ window = malloc(WSIZE);
+ if (!window || !header_buf || !symlink_buf || !name_buf)
+ panic("can't allocate buffers");
+ state = Start;
+ this_header = 0;
+ message = NULL;
+ while (!message && len) {
+ loff_t saved_offset = this_header;
+ if (*buf == '0' && !(this_header & 3)) {
+ state = Start;
+ written = write_buffer(buf, len);
+ buf += written;
+ len -= written;
+ continue;
+ }
+ if (!*buf) {
+ buf++;
+ len--;
+ this_header++;
+ continue;
+ }
+ this_header = 0;
+ insize = len;
+ inbuf = buf;
+ inptr = 0;
+ outcnt = 0; /* bytes in output buffer */
+ bytes_out = 0;
+ crc = (ulg)0xffffffffL; /* shift register contents */
+ makecrc();
+ gunzip();
+ if (state != Reset)
+ error("junk in gzipped archive");
+ this_header = saved_offset + inptr;
+ buf += inptr;
+ len -= inptr;
+ }
+ free(window);
+ free(name_buf);
+ free(symlink_buf);
+ free(header_buf);
+ return message;
+}
+
+extern char __initramfs_start[], __initramfs_end[];
+#ifdef CONFIG_BLK_DEV_INITRD
+#include <linux/initrd.h>
+#endif
+
+void __init populate_rootfs(void)
+{
+ char *err = unpack_to_rootfs(__initramfs_start,
+ __initramfs_end - __initramfs_start, 0);
+ if (err)
+ panic(err);
+#ifdef CONFIG_BLK_DEV_INITRD
+ if (initrd_start) {
+ int fd;
+ printk(KERN_INFO "checking if image is initramfs...");
+ err = unpack_to_rootfs((char *)initrd_start,
+ initrd_end - initrd_start, 1);
+ if (!err) {
+ printk(" it is\n");
+ unpack_to_rootfs((char *)initrd_start,
+ initrd_end - initrd_start, 0);
+ free_initrd_mem(initrd_start, initrd_end);
+ return;
+ }
+ printk("it isn't (%s); looks like an initrd\n", err);
+ fd = sys_open("/initrd.image", O_WRONLY|O_CREAT, 700);
+ if (fd >= 0) {
+ sys_write(fd, (char *)initrd_start,
+ initrd_end - initrd_start);
+ sys_close(fd);
+ free_initrd_mem(initrd_start, initrd_end);
+ }
+ }
+#endif
+}