add directory kernel

kernel/0.95/linux-0.95/fs/minix/Makefile

@@ -0,0 +1,69 @@
+AR	=ar
+AS	=as
+CC	=gcc
+LD	=ld
+CFLAGS	=-Wall -O -fstrength-reduce -fomit-frame-pointer \
+	-nostdinc -I../../include
+CPP	=gcc -E -nostdinc -I../../include
+
+.c.s:
+	$(CC) $(CFLAGS) \
+	-S -o $*.s $<
+.c.o:
+	$(CC) $(CFLAGS) \
+	-c -o $*.o $<
+.s.o:
+	$(AS) -o $*.o $<
+
+OBJS=	minix_op.o bitmap.o truncate.o namei.o inode.o file_dev.o
+
+minix.o: $(OBJS)
+	$(LD) -r -o minix.o $(OBJS)
+
+clean:
+	rm -f core *.o *.a tmp_make
+	for i in *.c;do rm -f `basename $$i .c`.s;done
+
+dep:
+	sed '/\#\#\# Dependencies/q' < Makefile > tmp_make
+	(for i in *.c;do $(CPP) -M $$i;done) >> tmp_make
+	cp tmp_make Makefile
+
+### Dependencies:
+bitmap.o : bitmap.c ../../include/string.h ../../include/linux/sched.h \
+  ../../include/linux/head.h ../../include/linux/fs.h \
+  ../../include/sys/types.h ../../include/linux/mm.h \
+  ../../include/linux/kernel.h ../../include/signal.h \
+  ../../include/sys/param.h ../../include/sys/time.h ../../include/time.h \
+  ../../include/sys/resource.h ../../include/linux/minix_fs.h 
+file_dev.o : file_dev.c ../../include/errno.h ../../include/fcntl.h \
+  ../../include/sys/types.h ../../include/linux/sched.h \
+  ../../include/linux/head.h ../../include/linux/fs.h \
+  ../../include/linux/mm.h ../../include/linux/kernel.h \
+  ../../include/signal.h ../../include/sys/param.h ../../include/sys/time.h \
+  ../../include/time.h ../../include/sys/resource.h \
+  ../../include/linux/minix_fs.h ../../include/asm/segment.h 
+inode.o : inode.c ../../include/string.h ../../include/sys/stat.h \
+  ../../include/sys/types.h ../../include/linux/sched.h \
+  ../../include/linux/head.h ../../include/linux/fs.h \
+  ../../include/linux/mm.h ../../include/linux/kernel.h \
+  ../../include/signal.h ../../include/sys/param.h ../../include/sys/time.h \
+  ../../include/time.h ../../include/sys/resource.h \
+  ../../include/linux/minix_fs.h ../../include/asm/system.h 
+minix_op.o : minix_op.c ../../include/linux/fs.h ../../include/sys/types.h \
+  ../../include/linux/minix_fs.h 
+namei.o : namei.c ../../include/linux/sched.h ../../include/linux/head.h \
+  ../../include/linux/fs.h ../../include/sys/types.h ../../include/linux/mm.h \
+  ../../include/linux/kernel.h ../../include/signal.h \
+  ../../include/sys/param.h ../../include/sys/time.h ../../include/time.h \
+  ../../include/sys/resource.h ../../include/linux/minix_fs.h \
+  ../../include/asm/segment.h ../../include/string.h ../../include/fcntl.h \
+  ../../include/errno.h ../../include/const.h ../../include/sys/stat.h 
+truncate.o : truncate.c ../../include/linux/sched.h \
+  ../../include/linux/head.h ../../include/linux/fs.h \
+  ../../include/sys/types.h ../../include/linux/mm.h \
+  ../../include/linux/kernel.h ../../include/signal.h \
+  ../../include/sys/param.h ../../include/sys/time.h ../../include/time.h \
+  ../../include/sys/resource.h ../../include/linux/minix_fs.h \
+  ../../include/linux/tty.h ../../include/termios.h ../../include/errno.h \
+  ../../include/fcntl.h ../../include/sys/stat.h 

kernel/0.95/linux-0.95/fs/minix/bitmap.c

@@ -0,0 +1,184 @@
+/*
+ *  linux/fs/bitmap.c
+ *
+ *  (C) 1991  Linus Torvalds
+ */
+
+/* bitmap.c contains the code that handles the inode and block bitmaps */
+#include <string.h>
+
+#include <linux/sched.h>
+#include <linux/minix_fs.h>
+#include <linux/kernel.h>
+
+#define clear_block(addr) \
+__asm__("cld\n\t" \
+	"rep\n\t" \
+	"stosl" \
+	::"a" (0),"c" (BLOCK_SIZE/4),"D" ((long) (addr)):"cx","di")
+
+#define set_bit(nr,addr) ({\
+char res; \
+__asm__ __volatile__("btsl %1,%2\n\tsetb %0": \
+"=q" (res):"r" (nr),"m" (*(addr))); \
+res;})
+
+#define clear_bit(nr,addr) ({\
+char res; \
+__asm__ __volatile__("btrl %1,%2\n\tsetnb %0": \
+"=q" (res):"r" (nr),"m" (*(addr))); \
+res;})
+
+#define find_first_zero(addr) ({ \
+int __res; \
+__asm__("cld\n" \
+	"1:\tlodsl\n\t" \
+	"notl %%eax\n\t" \
+	"bsfl %%eax,%%edx\n\t" \
+	"jne 2f\n\t" \
+	"addl $32,%%ecx\n\t" \
+	"cmpl $8192,%%ecx\n\t" \
+	"jl 1b\n\t" \
+	"xorl %%edx,%%edx\n" \
+	"2:\taddl %%edx,%%ecx" \
+	:"=c" (__res):"0" (0),"S" (addr):"ax","dx","si"); \
+__res;})
+
+int minix_free_block(int dev, int block)
+{
+	struct super_block * sb;
+	struct buffer_head * bh;
+	unsigned int bit,zone;
+
+	if (!(sb = get_super(dev)))
+		panic("trying to free block on nonexistent device");
+	if (block < sb->s_firstdatazone || block >= sb->s_nzones)
+		panic("trying to free block not in datazone");
+	bh = get_hash_table(dev,block);
+	if (bh) {
+		if (bh->b_count > 1) {
+			brelse(bh);
+			return 0;
+		}
+		bh->b_dirt=0;
+		bh->b_uptodate=0;
+		if (bh->b_count)
+			brelse(bh);
+	}
+	zone = block - sb->s_firstdatazone + 1;
+	bit = zone & 8191;
+	zone >>= 13;
+	bh = sb->s_zmap[zone];
+	if (clear_bit(bit,bh->b_data))
+		printk("free_block (%04x:%d): bit already cleared\n",dev,block);
+	bh->b_dirt = 1;
+	return 1;
+}
+
+int minix_new_block(int dev)
+{
+	struct buffer_head * bh;
+	struct super_block * sb;
+	int i,j;
+
+	if (!(sb = get_super(dev)))
+		panic("trying to get new block from nonexistant device");
+	j = 8192;
+	for (i=0 ; i<8 ; i++)
+		if (bh=sb->s_zmap[i])
+			if ((j=find_first_zero(bh->b_data))<8192)
+				break;
+	if (i>=8 || !bh || j>=8192)
+		return 0;
+	if (set_bit(j,bh->b_data))
+		panic("new_block: bit already set");
+	bh->b_dirt = 1;
+	j += i*8192 + sb->s_firstdatazone-1;
+	if (j >= sb->s_nzones)
+		return 0;
+	if (!(bh=getblk(dev,j)))
+		panic("new_block: cannot get block");
+	if (bh->b_count != 1)
+		panic("new block: count is != 1");
+	clear_block(bh->b_data);
+	bh->b_uptodate = 1;
+	bh->b_dirt = 1;
+	brelse(bh);
+	return j;
+}
+
+void minix_free_inode(struct inode * inode)
+{
+	struct buffer_head * bh;
+
+	if (!inode)
+		return;
+	if (!inode->i_dev) {
+		memset(inode,0,sizeof(*inode));
+		return;
+	}
+	if (inode->i_count>1) {
+		printk("free_inode: inode has count=%d\n",inode->i_count);
+		return;
+	}
+	if (inode->i_nlink) {
+		printk("free_inode: inode has nlink=%d\n",inode->i_nlink);
+		return;
+	}
+	if (!inode->i_sb) {
+		printk("free_inode: inode on nonexistent device\n");
+		return;
+	}
+	if (inode->i_ino < 1 || inode->i_ino > inode->i_sb->s_ninodes) {
+		printk("free_inode: inode 0 or nonexistent inode\n");
+		return;
+	}
+	if (!(bh=inode->i_sb->s_imap[inode->i_ino>>13])) {
+		printk("free_inode: nonexistent imap in superblock\n");
+		return;
+	}
+	if (clear_bit(inode->i_ino&8191,bh->b_data))
+		printk("free_inode: bit already cleared.\n\r");
+	bh->b_dirt = 1;
+	memset(inode,0,sizeof(*inode));
+}
+
+struct inode * minix_new_inode(int dev)
+{
+	struct inode * inode;
+	struct buffer_head * bh;
+	int i,j;
+
+	if (!(inode=get_empty_inode()))
+		return NULL;
+	if (!(inode->i_sb = get_super(dev))) {
+		printk("new_inode: unknown device\n");
+		iput(inode);
+		return NULL;
+	}
+	j = 8192;
+	for (i=0 ; i<8 ; i++)
+		if (bh=inode->i_sb->s_imap[i])
+			if ((j=find_first_zero(bh->b_data))<8192)
+				break;
+	if (!bh || j >= 8192 || j+i*8192 > inode->i_sb->s_ninodes) {
+		iput(inode);
+		return NULL;
+	}
+	if (set_bit(j,bh->b_data)) {	/* shouldn't happen */
+		printk("new_inode: bit already set");
+		iput(inode);
+		return NULL;
+	}
+	bh->b_dirt = 1;
+	inode->i_count = 1;
+	inode->i_nlink = 1;
+	inode->i_dev = dev;
+	inode->i_uid = current->euid;
+	inode->i_gid = current->egid;
+	inode->i_dirt = 1;
+	inode->i_ino = j + i*8192;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+	inode->i_op = &minix_inode_operations;
+	return inode;
+}

kernel/0.95/linux-0.95/fs/minix/file_dev.c

@@ -0,0 +1,105 @@
+/*
+ *  linux/fs/file_dev.c
+ *
+ *  (C) 1991  Linus Torvalds
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+
+#include <linux/sched.h>
+#include <linux/minix_fs.h>
+#include <linux/kernel.h>
+#include <asm/segment.h>
+
+#define MIN(a,b) (((a)<(b))?(a):(b))
+#define MAX(a,b) (((a)>(b))?(a):(b))
+
+int minix_file_read(struct inode * inode, struct file * filp, char * buf, int count)
+{
+	int read,left,chars,nr;
+	struct buffer_head * bh;
+
+	if (filp->f_pos > inode->i_size)
+		left = 0;
+	else
+		left = inode->i_size - filp->f_pos;
+	if (left > count)
+		left = count;
+	read = 0;
+	while (left > 0) {
+		if (nr = bmap(inode,(filp->f_pos)>>BLOCK_SIZE_BITS)) {
+			if (!(bh=bread(inode->i_dev,nr)))
+				return read?read:-EIO;
+		} else
+			bh = NULL;
+		nr = filp->f_pos & (BLOCK_SIZE-1);
+		chars = MIN( BLOCK_SIZE-nr , left );
+		filp->f_pos += chars;
+		left -= chars;
+		read += chars;
+		if (bh) {
+			char * p = nr + bh->b_data;
+			while (chars-->0)
+				put_fs_byte(*(p++),buf++);
+			brelse(bh);
+		} else {
+			while (chars-->0)
+				put_fs_byte(0,buf++);
+		}
+	}
+	inode->i_atime = CURRENT_TIME;
+	return read;
+}
+
+int minix_file_write(struct inode * inode, struct file * filp, char * buf, int count)
+{
+	off_t pos;
+	int written,block,c;
+	struct buffer_head * bh;
+	char * p;
+
+/*
+ * ok, append may not work when many processes are writing at the same time
+ * but so what. That way leads to madness anyway.
+ */
+	if (filp->f_flags & O_APPEND)
+		pos = inode->i_size;
+	else
+		pos = filp->f_pos;
+	written = 0;
+	while (written<count) {
+		if (!(block = minix_create_block(inode,pos/BLOCK_SIZE))) {
+			if (!written)
+				written = -ENOSPC;
+			break;
+		}
+		if (!(bh=bread(inode->i_dev,block))) {
+			if (!written)
+				written = -EIO;
+			break;
+		}
+		c = pos % BLOCK_SIZE;
+		p = c + bh->b_data;
+		bh->b_dirt = 1;
+		c = BLOCK_SIZE-c;
+		if (c > count-written)
+			c = count-written;
+		pos += c;
+		if (pos > inode->i_size) {
+			inode->i_size = pos;
+			inode->i_dirt = 1;
+		}
+		written += c;
+		while (c-->0)
+			*(p++) = get_fs_byte(buf++);
+		brelse(bh);
+	}
+	inode->i_mtime = CURRENT_TIME;
+	if (!(filp->f_flags & O_APPEND)) {
+		filp->f_pos = pos;
+		inode->i_ctime = CURRENT_TIME;
+		inode->i_dirt = 1;
+	}
+	return written;
+}

kernel/0.95/linux-0.95/fs/minix/inode.c

@@ -0,0 +1,145 @@
+/*
+ *  linux/fs/minix/inode.c
+ *
+ *  (C) 1991  Linus Torvalds
+ */
+
+#include <string.h>
+#include <sys/stat.h>
+
+#include <linux/sched.h>
+#include <linux/minix_fs.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <asm/system.h>
+
+static int _bmap(struct inode * inode,int block,int create)
+{
+	struct buffer_head * bh;
+	int i;
+
+	if (block<0)
+		panic("_bmap: block<0");
+	if (block >= 7+512+512*512)
+		panic("_bmap: block>big");
+	if (block<7) {
+		if (create && !inode->i_data[block])
+			if (inode->i_data[block]=minix_new_block(inode->i_dev)) {
+				inode->i_ctime=CURRENT_TIME;
+				inode->i_dirt=1;
+			}
+		return inode->i_data[block];
+	}
+	block -= 7;
+	if (block<512) {
+		if (create && !inode->i_data[7])
+			if (inode->i_data[7]=minix_new_block(inode->i_dev)) {
+				inode->i_dirt=1;
+				inode->i_ctime=CURRENT_TIME;
+			}
+		if (!inode->i_data[7])
+			return 0;
+		if (!(bh = bread(inode->i_dev,inode->i_data[7])))
+			return 0;
+		i = ((unsigned short *) (bh->b_data))[block];
+		if (create && !i)
+			if (i=minix_new_block(inode->i_dev)) {
+				((unsigned short *) (bh->b_data))[block]=i;
+				bh->b_dirt=1;
+			}
+		brelse(bh);
+		return i;
+	}
+	block -= 512;
+	if (create && !inode->i_data[8])
+		if (inode->i_data[8]=minix_new_block(inode->i_dev)) {
+			inode->i_dirt=1;
+			inode->i_ctime=CURRENT_TIME;
+		}
+	if (!inode->i_data[8])
+		return 0;
+	if (!(bh=bread(inode->i_dev,inode->i_data[8])))
+		return 0;
+	i = ((unsigned short *)bh->b_data)[block>>9];
+	if (create && !i)
+		if (i=minix_new_block(inode->i_dev)) {
+			((unsigned short *) (bh->b_data))[block>>9]=i;
+			bh->b_dirt=1;
+		}
+	brelse(bh);
+	if (!i)
+		return 0;
+	if (!(bh=bread(inode->i_dev,i)))
+		return 0;
+	i = ((unsigned short *)bh->b_data)[block&511];
+	if (create && !i)
+		if (i=minix_new_block(inode->i_dev)) {
+			((unsigned short *) (bh->b_data))[block&511]=i;
+			bh->b_dirt=1;
+		}
+	brelse(bh);
+	return i;
+}
+
+int minix_bmap(struct inode * inode,int block)
+{
+	return _bmap(inode,block,0);
+}
+
+int minix_create_block(struct inode * inode, int block)
+{
+	return _bmap(inode,block,1);
+}
+
+void minix_read_inode(struct inode * inode)
+{
+	struct buffer_head * bh;
+	struct minix_inode * raw_inode;
+	int block;
+
+	block = 2 + inode->i_sb->s_imap_blocks + inode->i_sb->s_zmap_blocks +
+		(inode->i_ino-1)/MINIX_INODES_PER_BLOCK;
+	if (!(bh=bread(inode->i_dev,block)))
+		panic("unable to read i-node block");
+	raw_inode = ((struct minix_inode *) bh->b_data) +
+		(inode->i_ino-1)%MINIX_INODES_PER_BLOCK;
+	inode->i_mode = raw_inode->i_mode;
+	inode->i_uid = raw_inode->i_uid;
+	inode->i_gid = raw_inode->i_gid;
+	inode->i_nlink = raw_inode->i_nlinks;
+	inode->i_size = raw_inode->i_size;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = raw_inode->i_time;
+	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
+		inode->i_rdev = raw_inode->i_zone[0];
+	else for (block = 0; block < 9; block++)
+		inode->i_data[block] = raw_inode->i_zone[block];
+	brelse(bh);
+	inode->i_op = &minix_inode_operations;
+}
+
+void minix_write_inode(struct inode * inode)
+{
+	struct buffer_head * bh;
+	struct minix_inode * raw_inode;
+	int block;
+
+	block = 2 + inode->i_sb->s_imap_blocks + inode->i_sb->s_zmap_blocks +
+		(inode->i_ino-1)/MINIX_INODES_PER_BLOCK;
+	if (!(bh=bread(inode->i_dev,block)))
+		panic("unable to read i-node block");
+	raw_inode = ((struct minix_inode *)bh->b_data) +
+		(inode->i_ino-1)%MINIX_INODES_PER_BLOCK;
+	raw_inode->i_mode = inode->i_mode;
+	raw_inode->i_uid = inode->i_uid;
+	raw_inode->i_gid = inode->i_gid;
+	raw_inode->i_nlinks = inode->i_nlink;
+	raw_inode->i_size = inode->i_size;
+	raw_inode->i_time = inode->i_mtime;
+	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
+		raw_inode->i_zone[0] = inode->i_rdev;
+	else for (block = 0; block < 9; block++)
+		raw_inode->i_zone[block] = inode->i_data[block];
+	bh->b_dirt=1;
+	inode->i_dirt=0;
+	brelse(bh);
+}

kernel/0.95/linux-0.95/fs/minix/minix_op.c

@@ -0,0 +1,38 @@
+/*
+ * linux/fs/minix/minix_op.c
+ *
+ * structures for the minix super_block/inode/file-operations
+ */
+
+#include <linux/fs.h>
+#include <linux/minix_fs.h>
+
+/*
+ * These are the low-level inode operations for minix filesystem inodes.
+ */
+struct inode_operations minix_inode_operations = {
+	minix_create,
+	minix_lookup,
+	minix_link,
+	minix_unlink,
+	minix_symlink,
+	minix_mkdir,
+	minix_rmdir,
+	minix_mknod,
+	minix_rename,
+	minix_readlink,
+	minix_open,
+	minix_release,
+	minix_follow_link
+};
+
+/*
+ * We have just NULL's here: the current defaults are ok for
+ * the minix filesystem.
+ */
+struct file_operations minix_file_operations = {
+	NULL,	/* lseek */
+	NULL,	/* read */
+	NULL	/* write */
+};
+	

kernel/0.95/linux-0.95/fs/minix/namei.c

@@ -0,0 +1,795 @@
+/*
+ *  linux/fs/minix/namei.c
+ *
+ *  (C) 1991  Linus Torvalds
+ */
+
+#include <linux/sched.h>
+#include <linux/minix_fs.h>
+#include <linux/kernel.h>
+#include <asm/segment.h>
+
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <const.h>
+#include <sys/stat.h>
+
+extern int permission(struct inode * inode,int mask);
+extern struct inode * _namei(const char * filename, struct inode * base,
+	int follow_links);
+
+/*
+ * comment out this line if you want names > MINIX_NAME_LEN chars to be
+ * truncated. Else they will be disallowed.
+ */
+/* #define NO_TRUNCATE */
+
+/*
+ * ok, we cannot use strncmp, as the name is not in our data space.
+ * Thus we'll have to use minix_match. No big problem. Match also makes
+ * some sanity tests.
+ *
+ * NOTE! unlike strncmp, minix_match returns 1 for success, 0 for failure.
+ */
+static int minix_match(int len,const char * name,struct minix_dir_entry * de)
+{
+	register int same __asm__("ax");
+
+	if (!de || !de->inode || len > MINIX_NAME_LEN)
+		return 0;
+	/* "" means "." ---> so paths like "/usr/lib//libc.a" work */
+	if (!len && (de->name[0]=='.') && (de->name[1]=='\0'))
+		return 1;
+	if (len < MINIX_NAME_LEN && de->name[len])
+		return 0;
+	__asm__("cld\n\t"
+		"fs ; repe ; cmpsb\n\t"
+		"setz %%al"
+		:"=a" (same)
+		:"0" (0),"S" ((long) name),"D" ((long) de->name),"c" (len)
+		:"cx","di","si");
+	return same;
+}
+
+/*
+ *	minix_find_entry()
+ *
+ * finds an entry in the specified directory with the wanted name. It
+ * returns the cache buffer in which the entry was found, and the entry
+ * itself (as a parameter - res_dir). It does NOT read the inode of the
+ * entry - you'll have to do that yourself if you want to.
+ */
+static struct buffer_head * minix_find_entry(struct inode * dir,
+	const char * name, int namelen, struct minix_dir_entry ** res_dir)
+{
+	int entries;
+	int block,i;
+	struct buffer_head * bh;
+	struct minix_dir_entry * de;
+
+	*res_dir = NULL;
+	if (!dir)
+		return NULL;
+#ifdef NO_TRUNCATE
+	if (namelen > MINIX_NAME_LEN)
+		return NULL;
+#else
+	if (namelen > MINIX_NAME_LEN)
+		namelen = MINIX_NAME_LEN;
+#endif
+	entries = dir->i_size / (sizeof (struct minix_dir_entry));
+	if (!(block = dir->i_data[0]))
+		return NULL;
+	if (!(bh = bread(dir->i_dev,block)))
+		return NULL;
+	i = 0;
+	de = (struct minix_dir_entry *) bh->b_data;
+	while (i < entries) {
+		if ((char *)de >= BLOCK_SIZE+bh->b_data) {
+			brelse(bh);
+			bh = NULL;
+			if (!(block = bmap(dir,i/MINIX_DIR_ENTRIES_PER_BLOCK)) ||
+			    !(bh = bread(dir->i_dev,block))) {
+				i += MINIX_DIR_ENTRIES_PER_BLOCK;
+				continue;
+			}
+			de = (struct minix_dir_entry *) bh->b_data;
+		}
+		if (minix_match(namelen,name,de)) {
+			*res_dir = de;
+			return bh;
+		}
+		de++;
+		i++;
+	}
+	brelse(bh);
+	return NULL;
+}
+
+struct inode * minix_follow_link(struct inode * dir, struct inode * inode)
+{
+	unsigned short fs;
+	struct buffer_head * bh;
+
+	if (!dir) {
+		dir = current->root;
+		dir->i_count++;
+	}
+	if (!inode) {
+		iput(dir);
+		return NULL;
+	}
+	if (!S_ISLNK(inode->i_mode)) {
+		iput(dir);
+		return inode;
+	}
+	__asm__("mov %%fs,%0":"=r" (fs));
+	if ((current->link_count > 5) || !inode->i_data[0] ||
+	   !(bh = bread(inode->i_dev, inode->i_data[0]))) {
+		iput(dir);
+		iput(inode);
+		return NULL;
+	}
+	iput(inode);
+	__asm__("mov %0,%%fs"::"r" ((unsigned short) 0x10));
+	current->link_count++;
+	inode = _namei(bh->b_data,dir,1);
+	current->link_count--;
+	__asm__("mov %0,%%fs"::"r" (fs));
+	brelse(bh);
+	return inode;
+}
+
+int minix_lookup(struct inode * dir,const char * name, int len,
+	struct inode ** result)
+{
+	int ino;
+	struct minix_dir_entry * de;
+	struct buffer_head * bh;
+
+	*result = NULL;
+	if (!dir)
+		return -ENOENT;
+	if (!S_ISDIR(dir->i_mode)) {
+		iput(dir);
+		return -ENOENT;
+	}
+	if (!(bh = minix_find_entry(dir,name,len,&de))) {
+		iput(dir);
+		return -ENOENT;
+	}
+	ino = de->inode;
+	brelse(bh);
+	if (!(*result = iget(dir->i_dev,ino))) {
+		iput(dir);
+		return -EACCES;
+	}
+	iput(dir);
+	return 0;
+}
+
+/*
+ *	minix_add_entry()
+ *
+ * adds a file entry to the specified directory, using the same
+ * semantics as minix_find_entry(). It returns NULL if it failed.
+ *
+ * NOTE!! The inode part of 'de' is left at 0 - which means you
+ * may not sleep between calling this and putting something into
+ * the entry, as someone else might have used it while you slept.
+ */
+static struct buffer_head * minix_add_entry(struct inode * dir,
+	const char * name, int namelen, struct minix_dir_entry ** res_dir)
+{
+	int block,i;
+	struct buffer_head * bh;
+	struct minix_dir_entry * de;
+
+	*res_dir = NULL;
+	if (!dir)
+		return NULL;
+#ifdef NO_TRUNCATE
+	if (namelen > MINIX_NAME_LEN)
+		return NULL;
+#else
+	if (namelen > MINIX_NAME_LEN)
+		namelen = MINIX_NAME_LEN;
+#endif
+	if (!namelen)
+		return NULL;
+	if (!(block = dir->i_data[0]))
+		return NULL;
+	if (!(bh = bread(dir->i_dev,block)))
+		return NULL;
+	i = 0;
+	de = (struct minix_dir_entry *) bh->b_data;
+	while (1) {
+		if ((char *)de >= BLOCK_SIZE+bh->b_data) {
+			brelse(bh);
+			bh = NULL;
+			block = minix_create_block(dir,i/MINIX_DIR_ENTRIES_PER_BLOCK);
+			if (!block)
+				return NULL;
+			if (!(bh = bread(dir->i_dev,block))) {
+				i += MINIX_DIR_ENTRIES_PER_BLOCK;
+				continue;
+			}
+			de = (struct minix_dir_entry *) bh->b_data;
+		}
+		if (i*sizeof(struct minix_dir_entry) >= dir->i_size) {
+			de->inode=0;
+			dir->i_size = (i+1)*sizeof(struct minix_dir_entry);
+			dir->i_dirt = 1;
+			dir->i_ctime = CURRENT_TIME;
+		}
+		if (!de->inode) {
+			dir->i_mtime = CURRENT_TIME;
+			for (i=0; i < MINIX_NAME_LEN ; i++)
+				de->name[i]=(i<namelen)?get_fs_byte(name+i):0;
+			bh->b_dirt = 1;
+			*res_dir = de;
+			return bh;
+		}
+		de++;
+		i++;
+	}
+	brelse(bh);
+	return NULL;
+}
+
+int minix_create(struct inode * dir,const char * name, int len, int mode,
+	struct inode ** result)
+{
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct minix_dir_entry * de;
+
+	*result = NULL;
+	if (!dir)
+		return -ENOENT;
+	inode = minix_new_inode(dir->i_dev);
+	if (!inode) {
+		iput(dir);
+		return -ENOSPC;
+	}
+	inode->i_mode = mode;
+	inode->i_dirt = 1;
+	bh = minix_add_entry(dir,name,len,&de);
+	if (!bh) {
+		inode->i_nlink--;
+		iput(inode);
+		iput(dir);
+		return -ENOSPC;
+	}
+	de->inode = inode->i_ino;
+	bh->b_dirt = 1;
+	brelse(bh);
+	iput(dir);
+	*result = inode;
+	return 0;
+}
+
+int minix_mknod(struct inode * dir, const char * name, int len, int mode, int rdev)
+{
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct minix_dir_entry * de;
+
+	if (!dir)
+		return -ENOENT;
+	bh = minix_find_entry(dir,name,len,&de);
+	if (bh) {
+		brelse(bh);
+		iput(dir);
+		return -EEXIST;
+	}
+	inode = minix_new_inode(dir->i_dev);
+	if (!inode) {
+		iput(dir);
+		return -ENOSPC;
+	}
+	inode->i_uid = current->euid;
+	inode->i_mode = mode;
+	if (S_ISBLK(mode) || S_ISCHR(mode))
+		inode->i_rdev = rdev;
+	inode->i_mtime = inode->i_atime = CURRENT_TIME;
+	inode->i_dirt = 1;
+	bh = minix_add_entry(dir,name,len,&de);
+	if (!bh) {
+		inode->i_nlink--;
+		iput(inode);
+		iput(dir);
+		return -ENOSPC;
+	}
+	de->inode = inode->i_ino;
+	bh->b_dirt = 1;
+	brelse(bh);
+	iput(dir);
+	iput(inode);
+	return 0;
+}
+
+int minix_mkdir(struct inode * dir, const char * name, int len, int mode)
+{
+	struct inode * inode;
+	struct buffer_head * bh, *dir_block;
+	struct minix_dir_entry * de;
+	
+	bh = minix_find_entry(dir,name,len,&de);
+	if (bh) {
+		brelse(bh);
+		iput(dir);
+		return -EEXIST;
+	}
+	inode = minix_new_inode(dir->i_dev);
+	if (!inode) {
+		iput(dir);
+		return -ENOSPC;
+	}
+	inode->i_size = 32;
+	inode->i_dirt = 1;
+	inode->i_mtime = inode->i_atime = CURRENT_TIME;
+	if (!(inode->i_data[0] = minix_new_block(inode->i_dev))) {
+		iput(dir);
+		inode->i_nlink--;
+		iput(inode);
+		return -ENOSPC;
+	}
+	inode->i_dirt = 1;
+	if (!(dir_block = bread(inode->i_dev,inode->i_data[0]))) {
+		iput(dir);
+		inode->i_nlink--;
+		iput(inode);
+		return -ERROR;
+	}
+	de = (struct minix_dir_entry *) dir_block->b_data;
+	de->inode=inode->i_ino;
+	strcpy(de->name,".");
+	de++;
+	de->inode = dir->i_ino;
+	strcpy(de->name,"..");
+	inode->i_nlink = 2;
+	dir_block->b_dirt = 1;
+	brelse(dir_block);
+	inode->i_mode = I_DIRECTORY | (mode & 0777 & ~current->umask);
+	inode->i_dirt = 1;
+	bh = minix_add_entry(dir,name,len,&de);
+	if (!bh) {
+		iput(dir);
+		inode->i_nlink=0;
+		iput(inode);
+		return -ENOSPC;
+	}
+	de->inode = inode->i_ino;
+	bh->b_dirt = 1;
+	dir->i_nlink++;
+	dir->i_dirt = 1;
+	iput(dir);
+	iput(inode);
+	brelse(bh);
+	return 0;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ */
+static int empty_dir(struct inode * inode)
+{
+	int nr,block;
+	int len;
+	struct buffer_head * bh;
+	struct minix_dir_entry * de;
+
+	len = inode->i_size / sizeof (struct minix_dir_entry);
+	if (len<2 || !inode->i_data[0] ||
+	    !(bh=bread(inode->i_dev,inode->i_data[0]))) {
+	    	printk("warning - bad directory on dev %04x\n",inode->i_dev);
+		return 0;
+	}
+	de = (struct minix_dir_entry *) bh->b_data;
+	if (de[0].inode != inode->i_ino || !de[1].inode || 
+	    strcmp(".",de[0].name) || strcmp("..",de[1].name)) {
+	    	printk("warning - bad directory on dev %04x\n",inode->i_dev);
+		return 0;
+	}
+	nr = 2;
+	de += 2;
+	while (nr<len) {
+		if ((void *) de >= (void *) (bh->b_data+BLOCK_SIZE)) {
+			brelse(bh);
+			block=bmap(inode,nr/MINIX_DIR_ENTRIES_PER_BLOCK);
+			if (!block) {
+				nr += MINIX_DIR_ENTRIES_PER_BLOCK;
+				continue;
+			}
+			if (!(bh=bread(inode->i_dev,block)))
+				return 0;
+			de = (struct minix_dir_entry *) bh->b_data;
+		}
+		if (de->inode) {
+			brelse(bh);
+			return 0;
+		}
+		de++;
+		nr++;
+	}
+	brelse(bh);
+	return 1;
+}
+
+int minix_rmdir(struct inode * dir, const char * name, int len)
+{
+	int retval;
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct minix_dir_entry * de;
+
+	inode = NULL;
+	bh = minix_find_entry(dir,name,len,&de);
+	retval = -ENOENT;
+	if (!bh)
+		goto end_rmdir;
+	retval = -EPERM;
+	if (!(inode = iget(dir->i_dev, de->inode)))
+		goto end_rmdir;
+	if ((dir->i_mode & S_ISVTX) && current->euid &&
+	   inode->i_uid != current->euid)
+		goto end_rmdir;
+	if (inode->i_dev != dir->i_dev)
+		goto end_rmdir;
+	if (inode == dir)	/* we may not delete ".", but "../dir" is ok */
+		goto end_rmdir;
+	if (!S_ISDIR(inode->i_mode)) {
+		retval = -ENOTDIR;
+		goto end_rmdir;
+	}
+	if (!empty_dir(inode)) {
+		retval = -ENOTEMPTY;
+		goto end_rmdir;
+	}
+	if (inode->i_count > 1) {
+		retval = -EBUSY;
+		goto end_rmdir;
+	}
+	if (inode->i_nlink != 2)
+		printk("empty directory has nlink!=2 (%d)\n",inode->i_nlink);
+	de->inode = 0;
+	bh->b_dirt = 1;
+	inode->i_nlink=0;
+	inode->i_dirt=1;
+	dir->i_nlink--;
+	dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+	dir->i_dirt=1;
+	retval = 0;
+end_rmdir:
+	iput(dir);
+	iput(inode);
+	brelse(bh);
+	return retval;
+}
+
+int minix_unlink(struct inode * dir, const char * name, int len)
+{
+	int retval;
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct minix_dir_entry * de;
+
+	retval = -ENOENT;
+	inode = NULL;
+	bh = minix_find_entry(dir,name,len,&de);
+	if (!bh)
+		goto end_unlink;
+	if (!(inode = iget(dir->i_dev, de->inode)))
+		goto end_unlink;
+	retval = -EPERM;
+	if ((dir->i_mode & S_ISVTX) && !suser() &&
+	    current->euid != inode->i_uid &&
+	    current->euid != dir->i_uid)
+		goto end_unlink;
+	if (S_ISDIR(inode->i_mode))
+		goto end_unlink;
+	if (!inode->i_nlink) {
+		printk("Deleting nonexistent file (%04x:%d), %d\n",
+			inode->i_dev,inode->i_ino,inode->i_nlink);
+		inode->i_nlink=1;
+	}
+	de->inode = 0;
+	bh->b_dirt = 1;
+	inode->i_nlink--;
+	inode->i_dirt = 1;
+	inode->i_ctime = CURRENT_TIME;
+	retval = 0;
+end_unlink:
+	brelse(bh);
+	iput(inode);
+	iput(dir);
+	return retval;
+}
+
+int minix_symlink(struct inode * dir, const char * name, int len, const char * symname)
+{
+	struct minix_dir_entry * de;
+	struct inode * inode = NULL;
+	struct buffer_head * bh = NULL, * name_block = NULL;
+	int i;
+	char c;
+
+	if (!(inode = minix_new_inode(dir->i_dev))) {
+		iput(dir);
+		return -ENOSPC;
+	}
+	inode->i_mode = S_IFLNK | 0777;
+	inode->i_dirt = 1;
+	if (!(inode->i_data[0] = minix_new_block(inode->i_dev))) {
+		iput(dir);
+		inode->i_nlink--;
+		iput(inode);
+		return -ENOSPC;
+	}
+	inode->i_dirt = 1;
+	if (!(name_block = bread(inode->i_dev,inode->i_data[0]))) {
+		iput(dir);
+		inode->i_nlink--;
+		iput(inode);
+		return -ERROR;
+	}
+	i = 0;
+	while (i < 1023 && (c=get_fs_byte(symname++)))
+		name_block->b_data[i++] = c;
+	name_block->b_data[i] = 0;
+	name_block->b_dirt = 1;
+	brelse(name_block);
+	inode->i_size = i;
+	inode->i_dirt = 1;
+	bh = minix_find_entry(dir,name,len,&de);
+	if (bh) {
+		inode->i_nlink--;
+		iput(inode);
+		brelse(bh);
+		iput(dir);
+		return -EEXIST;
+	}
+	bh = minix_add_entry(dir,name,len,&de);
+	if (!bh) {
+		inode->i_nlink--;
+		iput(inode);
+		iput(dir);
+		return -ENOSPC;
+	}
+	de->inode = inode->i_ino;
+	bh->b_dirt = 1;
+	brelse(bh);
+	iput(dir);
+	iput(inode);
+	return 0;
+}
+
+int minix_link(struct inode * oldinode, struct inode * dir, const char * name, int len)
+{
+	struct minix_dir_entry * de;
+	struct buffer_head * bh;
+
+	if (S_ISDIR(oldinode->i_mode)) {
+		iput(oldinode);
+		iput(dir);
+		return -EPERM;
+	}
+	bh = minix_find_entry(dir,name,len,&de);
+	if (bh) {
+		brelse(bh);
+		iput(dir);
+		iput(oldinode);
+		return -EEXIST;
+	}
+	bh = minix_add_entry(dir,name,len,&de);
+	if (!bh) {
+		iput(dir);
+		iput(oldinode);
+		return -ENOSPC;
+	}
+	de->inode = oldinode->i_ino;
+	bh->b_dirt = 1;
+	brelse(bh);
+	iput(dir);
+	oldinode->i_nlink++;
+	oldinode->i_ctime = CURRENT_TIME;
+	oldinode->i_dirt = 1;
+	iput(oldinode);
+	return 0;
+}
+
+static int subdir(struct inode * new, struct inode * old)
+{
+	unsigned short fs;
+	int ino;
+	int result;
+
+	__asm__("mov %%fs,%0":"=r" (fs));
+	__asm__("mov %0,%%fs"::"r" ((unsigned short) 0x10));
+	new->i_count++;
+	result = 0;
+	for (;;) {
+		if (new == old) {
+			result = 1;
+			break;
+		}
+		if (new->i_dev != old->i_dev)
+			break;
+		ino = new->i_ino;
+		if (minix_lookup(new,"..",2,&new))
+			break;
+		if (new->i_ino == ino)
+			break;
+	}
+	iput(new);
+	__asm__("mov %0,%%fs"::"r" (fs));
+	return result;
+}
+
+#define PARENT_INO(buffer) \
+(((struct minix_dir_entry *) (buffer))[1].inode)
+
+#define PARENT_NAME(buffer) \
+(((struct minix_dir_entry *) (buffer))[1].name)
+
+/*
+ * rename uses retrying to avoid race-conditions: at least they should be minimal.
+ * it tries to allocate all the blocks, then sanity-checks, and if the sanity-
+ * checks fail, it tries to restart itself again. Very practical - no changes
+ * are done until we know everything works ok.. and then all the changes can be
+ * done in one fell swoop when we have claimed all the buffers needed.
+ *
+ * Anybody can rename anything with this: the permission checks are left to the
+ * higher-level routines.
+ */
+static int do_minix_rename(struct inode * old_dir, const char * old_name, int old_len,
+	struct inode * new_dir, const char * new_name, int new_len)
+{
+	struct inode * old_inode, * new_inode;
+	struct buffer_head * old_bh, * new_bh, * dir_bh;
+	struct minix_dir_entry * old_de, * new_de;
+	int retval;
+
+	goto start_up;
+try_again:
+	brelse(old_bh);
+	brelse(new_bh);
+	brelse(dir_bh);
+	iput(old_inode);
+	iput(new_inode);
+	current->counter = 0;
+	schedule();
+start_up:
+	old_inode = new_inode = NULL;
+	old_bh = new_bh = dir_bh = NULL;
+	old_bh = minix_find_entry(old_dir,old_name,old_len,&old_de);
+	retval = -ENOENT;
+	if (!old_bh)
+		goto end_rename;
+	old_inode = iget(old_dir->i_dev, old_de->inode);
+	if (!old_inode)
+		goto end_rename;
+	new_bh = minix_find_entry(new_dir,new_name,new_len,&new_de);
+	if (new_bh) {
+		new_inode = iget(new_dir->i_dev, new_de->inode);
+		if (!new_inode) {
+			brelse(new_bh);
+			new_bh = NULL;
+		}
+	}
+	if (new_inode == old_inode) {
+		retval = 0;
+		goto end_rename;
+	}
+	if (S_ISDIR(old_inode->i_mode)) {
+		retval = -EEXIST;
+		if (new_bh)
+			goto end_rename;
+		retval = -EACCES;
+		if (!permission(old_inode, MAY_WRITE))
+			goto end_rename;
+		retval = -EINVAL;
+		if (subdir(new_dir, old_inode))
+			goto end_rename;
+		retval = -EIO;
+		if (!old_inode->i_data[0])
+			goto end_rename;
+		if (!(dir_bh = bread(old_inode->i_dev, old_inode->i_data[0])))
+			goto end_rename;
+		if (PARENT_INO(dir_bh->b_data) != old_dir->i_ino)
+			goto end_rename;
+	}
+	if (!new_bh)
+		new_bh = minix_add_entry(new_dir,new_name,new_len,&new_de);
+	retval = -ENOSPC;
+	if (!new_bh)
+		goto end_rename;
+/* sanity checking before doing the rename - avoid races */
+	if (new_inode && (new_de->inode != new_inode->i_ino))
+		goto try_again;
+	if (new_de->inode && !new_inode)
+		goto try_again;
+	if (old_de->inode != old_inode->i_ino)
+		goto try_again;
+/* ok, that's it */
+	old_de->inode = 0;
+	new_de->inode = old_inode->i_ino;
+	if (new_inode)
+		new_inode->i_nlink--;
+	old_bh->b_dirt = 1;
+	new_bh->b_dirt = 1;
+	if (dir_bh) {
+		PARENT_INO(dir_bh->b_data) = new_dir->i_ino;
+		dir_bh->b_dirt = 1;
+		old_dir->i_nlink--;
+		new_dir->i_nlink++;
+		old_dir->i_dirt = 1;
+		new_dir->i_dirt = 1;
+	}
+	retval = 0;
+end_rename:
+	brelse(dir_bh);
+	brelse(old_bh);
+	brelse(new_bh);
+	iput(old_inode);
+	iput(new_inode);
+	iput(old_dir);
+	iput(new_dir);
+	return retval;
+}
+
+/*
+ * Ok, rename also locks out other renames, as they can change the parent of
+ * a directory, and we don't want any races. Other races are checked for by
+ * "do_rename()", which restarts if there are inconsistencies.
+ *
+ * Note that there is no race between different filesystems: it's only within
+ * the same device that races occur: many renames can happen at once, as long
+ * as they are on different partitions.
+ */
+int minix_rename(struct inode * old_dir, const char * old_name, int old_len,
+	struct inode * new_dir, const char * new_name, int new_len)
+{
+	static struct task_struct * wait = NULL;
+	static int lock = 0;
+	int result;
+
+	while (lock)
+		sleep_on(&wait);
+	lock = 1;
+	result = do_minix_rename(old_dir, old_name, old_len,
+		new_dir, new_name, new_len);
+	lock = 0;
+	wake_up(&wait);
+	return result;
+}
+
+int minix_readlink(struct inode * inode, char * buffer, int buflen)
+{
+	struct buffer_head * bh;
+	int i;
+	char c;
+
+	if (!S_ISLNK(inode->i_mode)) {
+		iput(inode);
+		return -EINVAL;
+	}
+	if (buflen > 1023)
+		buflen = 1023;
+	if (inode->i_data[0])
+		bh = bread(inode->i_dev, inode->i_data[0]);
+	else
+		bh = NULL;
+	iput(inode);
+	if (!bh)
+		return 0;
+	i = 0;
+	while (i<buflen && (c = bh->b_data[i])) {
+		i++;
+		put_fs_byte(c,buffer++);
+	}
+	brelse(bh);
+	return i;
+}

kernel/0.95/linux-0.95/fs/minix/truncate.c

@@ -0,0 +1,154 @@
+/*
+ *  linux/fs/truncate.c
+ *
+ *  (C) 1991  Linus Torvalds
+ */
+
+#include <linux/sched.h>
+#include <linux/minix_fs.h>
+#include <linux/tty.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+static int minix_free_ind(int dev,int block)
+{
+	struct buffer_head * bh;
+	unsigned short * p;
+	int i;
+	int block_busy;
+
+	if (!block)
+		return 1;
+	block_busy = 0;
+	if (bh=bread(dev,block)) {
+		p = (unsigned short *) bh->b_data;
+		for (i=0;i<512;i++,p++)
+			if (*p)
+				if (minix_free_block(dev,*p)) {
+					*p = 0;
+					bh->b_dirt = 1;
+				} else
+					block_busy = 1;
+		brelse(bh);
+	}
+	if (block_busy)
+		return 0;
+	else
+		return minix_free_block(dev,block);
+}
+
+static int minix_free_dind(int dev,int block)
+{
+	struct buffer_head * bh;
+	unsigned short * p;
+	int i;
+	int block_busy;
+
+	if (!block)
+		return 1;
+	block_busy = 0;
+	if (bh=bread(dev,block)) {
+		p = (unsigned short *) bh->b_data;
+		for (i=0;i<512;i++,p++)
+			if (*p)
+				if (minix_free_ind(dev,*p)) {
+					*p = 0;
+					bh->b_dirt = 1;
+				} else
+					block_busy = 1;
+		brelse(bh);
+	}
+	if (block_busy)
+		return 0;
+	else
+		return minix_free_block(dev,block);
+}
+
+void minix_truncate(struct inode * inode)
+{
+	int i;
+	int block_busy;
+
+	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+	     S_ISLNK(inode->i_mode)))
+		return;
+repeat:
+	block_busy = 0;
+	for (i=0;i<7;i++)
+		if (inode->i_data[i]) {
+			if (minix_free_block(inode->i_dev,inode->i_data[i]))
+				inode->i_data[i]=0;
+			else
+				block_busy = 1;
+		}
+	if (minix_free_ind(inode->i_dev,inode->i_data[7]))
+		inode->i_data[7] = 0;
+	else
+		block_busy = 1;
+	if (minix_free_dind(inode->i_dev,inode->i_data[8]))
+		inode->i_data[8] = 0;
+	else
+		block_busy = 1;
+	inode->i_dirt = 1;
+	if (block_busy) {
+		current->counter = 0;
+		schedule();
+		goto repeat;
+	}
+	inode->i_size = 0;
+	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+}
+
+/*
+ * Called when a inode is released. Note that this is different
+ * from minix_open: open gets called at every open, but release
+ * gets called only when /all/ the files are closed.
+ */
+void minix_release(struct inode * inode, struct file * filp)
+{
+	printk("minix_release not implemented\n");
+}
+
+static int check_char_dev(struct inode * inode, struct file * filp)
+{
+	struct tty_struct *tty;
+	int min, dev;
+
+	dev = inode->i_rdev;
+	if (MAJOR(dev) == 4 || MAJOR(dev) == 5) {
+		if (MAJOR(dev) == 5)
+			min = current->tty;
+		else
+			min = MINOR(dev);
+		if (min < 0)
+			return -1;
+		if ((IS_A_PTY_MASTER(min)) && (inode->i_count>1))
+			return -1;
+		tty = TTY_TABLE(min);
+		if (!(filp->f_flags & O_NOCTTY) &&
+		    current->leader &&
+		    current->tty<0 &&
+		    tty->session==0) {
+			current->tty = min;
+			tty->session= current->session;
+			tty->pgrp = current->pgrp;
+		}
+	}
+	return 0;
+}
+
+/*
+ * Called every time a minix-file is opened
+ */
+int minix_open(struct inode * inode, struct file * filp)
+{
+	if (S_ISCHR(inode->i_mode)) {
+		if (check_char_dev(inode,filp))
+			return -EAGAIN;
+	} else if (S_ISBLK(inode->i_mode))
+		check_disk_change(inode->i_rdev);
+	filp->f_op = &minix_file_operations;
+	return 0;
+}