patch-1.3.60 linux/fs/msdos/inode.c

• Lines: 576
• Date: Thu Jan 1 02:00:00 1970
• Orig file: v1.3.59/linux/fs/msdos/inode.c
• Orig date: Tue Jan 23 21:15:50 1996

diff -u --recursive --new-file v1.3.59/linux/fs/msdos/inode.c linux/fs/msdos/inode.c
@@ -1,575 +0,0 @@
-/*
- *  linux/fs/msdos/inode.c
- *
- *  Written 1992,1993 by Werner Almesberger
- */
-
-#include <linux/module.h>
-
-#include <linux/msdos_fs.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/ctype.h>
-#include <linux/major.h>
-#include <linux/blkdev.h>
-#include <linux/fs.h>
-#include <linux/stat.h>
-#include <linux/locks.h>
-
-#include "msbuffer.h"
-
-#include <asm/segment.h>
-
-void msdos_put_inode(struct inode *inode)
-{
-	struct inode *depend;
-	struct super_block *sb;
-
-	if (inode->i_nlink) {
-		if (MSDOS_I(inode)->i_busy) cache_inval_inode(inode);
-		return;
-	}
-	inode->i_size = 0;
-	msdos_truncate(inode);
-	depend = MSDOS_I(inode)->i_depend;
-	sb = inode->i_sb;
-	clear_inode(inode);
-	if (depend) {
-		if (MSDOS_I(depend)->i_old != inode) {
-			printk("Invalid link (0x%p): expected 0x%p, got 0x%p\n",
-			    depend, inode, MSDOS_I(depend)->i_old);
-			fs_panic(sb,"...");
-			return;
-		}
-		MSDOS_I(depend)->i_old = NULL;
-		iput(depend);
-	}
-}
-
-
-void msdos_put_super(struct super_block *sb)
-{
-	cache_inval_dev(sb->s_dev);
-	set_blocksize (sb->s_dev,BLOCK_SIZE);
-	lock_super(sb);
-	sb->s_dev = 0;
-	unlock_super(sb);
-	MOD_DEC_USE_COUNT;
-	return;
-}
-
-
-static struct super_operations msdos_sops = { 
-	msdos_read_inode,
-	msdos_notify_change,
-	msdos_write_inode,
-	msdos_put_inode,
-	msdos_put_super,
-	NULL, /* added in 0.96c */
-	msdos_statfs,
-	NULL
-};
-
-
-static int parse_options(char *options,char *check,char *conversion,uid_t *uid,
-    gid_t *gid,int *umask,int *debug,int *fat,int *quiet,
-	int *blksize, char *dotsOK)
-{
-	char *this_char,*value;
-
-	*check = 'n';
-	*conversion = 'b';
-	*dotsOK = 0;
-	*uid = current->uid;
-	*gid = current->gid;
-	*umask = current->fs->umask;
-	*debug = *fat = *quiet = 0;
-	if (!options) return 1;
-	for (this_char = strtok(options,","); this_char; this_char = strtok(NULL,",")) {
-		if ((value = strchr(this_char,'=')) != NULL)
-			*value++ = 0;
-		if (!strcmp(this_char,"check") && value) {
-			if (value[0] && !value[1] && strchr("rns",*value))
-				*check = *value;
-			else if (!strcmp(value,"relaxed")) *check = 'r';
-			else if (!strcmp(value,"normal")) *check = 'n';
-			else if (!strcmp(value,"strict")) *check = 's';
-			else return 0;
-		}
-		else if (!strcmp(this_char,"conv") && value) {
-			if (value[0] && !value[1] && strchr("bta",*value))
-				*conversion = *value;
-			else if (!strcmp(value,"binary")) *conversion = 'b';
-			else if (!strcmp(value,"text")) *conversion = 't';
-			else if (!strcmp(value,"auto")) *conversion = 'a';
-			else return 0;
-		}
-		else if (!strcmp(this_char,"dots")) {
-		  *dotsOK = 1;
-		}
-		else if (!strcmp(this_char,"nodots")) {
-		  *dotsOK = 0;
-		}
-		else if (!strcmp(this_char,"dotsOK") && value) {
-			if (!strcmp(value,"yes")) *dotsOK = 1;
-			else if (!strcmp(value,"no")) *dotsOK = 0;
-			else return 0;
-		}
-		else if (!strcmp(this_char,"uid")) {
-			if (!value || !*value)
-				return 0;
-			*uid = simple_strtoul(value,&value,0);
-			if (*value)
-				return 0;
-		}
-		else if (!strcmp(this_char,"gid")) {
-			if (!value || !*value)
-				return 0;
-			*gid = simple_strtoul(value,&value,0);
-			if (*value)
-				return 0;
-		}
-		else if (!strcmp(this_char,"umask")) {
-			if (!value || !*value)
-				return 0;
-			*umask = simple_strtoul(value,&value,8);
-			if (*value)
-				return 0;
-		}
-		else if (!strcmp(this_char,"debug")) {
-			if (value) return 0;
-			*debug = 1;
-		}
-		else if (!strcmp(this_char,"fat")) {
-			if (!value || !*value)
-				return 0;
-			*fat = simple_strtoul(value,&value,0);
-			if (*value || (*fat != 12 && *fat != 16))
-				return 0;
-		}
-		else if (!strcmp(this_char,"quiet")) {
-			if (value) return 0;
-			*quiet = 1;
-		}
-		else if (!strcmp(this_char,"blocksize")) {
-			*blksize = simple_strtoul(value,&value,0);
-			if (*value)
-				return 0;
-			if (*blksize != 512 && *blksize != 1024){
-				printk ("MSDOS FS: Invalid blocksize (512 or 1024)\n");
-			}
-		}
-		else return 1;
-	}
-	return 1;
-}
-
-
-/* Read the super block of an MS-DOS FS. */
-
-struct super_block *msdos_read_super(struct super_block *sb,void *data,
-				     int silent)
-{
-	struct buffer_head *bh;
-	struct msdos_boot_sector *b;
-	int data_sectors,logical_sector_size,sector_mult,fat_clusters=0;
-	int debug,error,fat,quiet;
-	char check,conversion,dotsOK;
-	uid_t uid;
-	gid_t gid;
-	int umask;
-	int blksize = 512;
-
-	MOD_INC_USE_COUNT;
-	if (hardsect_size[MAJOR(sb->s_dev)] != NULL){
-		blksize = hardsect_size[MAJOR(sb->s_dev)][MINOR(sb->s_dev)];
-		if (blksize != 512){
-			printk ("MSDOS: Hardware sector size is %d\n",blksize);
-		}
-	}
-	if (!parse_options((char *) data,&check,&conversion,&uid,&gid,&umask,
-	    &debug,&fat,&quiet,&blksize,&dotsOK)
-		|| (blksize != 512 && blksize != 1024)) {
-		sb->s_dev = 0;
-		MOD_DEC_USE_COUNT;
-		return NULL;
-	}
-	cache_init();
-	lock_super(sb);
-	/* The first read is always 1024 bytes */
-	sb->s_blocksize = 1024;
-	set_blocksize(sb->s_dev, 1024);
-	bh = bread(sb->s_dev, 0, 1024);
-	unlock_super(sb);
-	if (bh == NULL || !msdos_is_uptodate(sb,bh)) {
-		brelse (bh);
-		sb->s_dev = 0;
-		printk("MSDOS bread failed\n");
-		MOD_DEC_USE_COUNT;
-		return NULL;
-	}
-	b = (struct msdos_boot_sector *) bh->b_data;
-	set_blocksize(sb->s_dev, blksize);
-/*
- * The DOS3 partition size limit is *not* 32M as many people think.  
- * Instead, it is 64K sectors (with the usual sector size being
- * 512 bytes, leading to a 32M limit).
- * 
- * DOS 3 partition managers got around this problem by faking a 
- * larger sector size, ie treating multiple physical sectors as 
- * a single logical sector.
- * 
- * We can accommodate this scheme by adjusting our cluster size,
- * fat_start, and data_start by an appropriate value.
- *
- * (by Drew Eckhardt)
- */
-
-#define ROUND_TO_MULTIPLE(n,m) ((n) && (m) ? (n)+(m)-1-((n)-1)%(m) : 0)
-    /* don't divide by zero */
-
-	logical_sector_size = CF_LE_W(*(unsigned short *) &b->sector_size);
-	sector_mult = logical_sector_size >> SECTOR_BITS;
-	MSDOS_SB(sb)->cluster_size = b->cluster_size*sector_mult;
-	MSDOS_SB(sb)->fats = b->fats;
-	MSDOS_SB(sb)->fat_start = CF_LE_W(b->reserved)*sector_mult;
-	MSDOS_SB(sb)->fat_length = CF_LE_W(b->fat_length)*sector_mult;
-	MSDOS_SB(sb)->dir_start = (CF_LE_W(b->reserved)+b->fats*CF_LE_W(
-	    b->fat_length))*sector_mult;
-	MSDOS_SB(sb)->dir_entries = CF_LE_W(*((unsigned short *) &b->dir_entries
-	    ));
-	MSDOS_SB(sb)->data_start = MSDOS_SB(sb)->dir_start+ROUND_TO_MULTIPLE((
-	    MSDOS_SB(sb)->dir_entries << MSDOS_DIR_BITS) >> SECTOR_BITS,
-	    sector_mult);
-	data_sectors = (CF_LE_W(*((unsigned short *) &b->sectors)) ?
-	    CF_LE_W(*((unsigned short *) &b->sectors)) :
-	    CF_LE_L(b->total_sect))*sector_mult-MSDOS_SB(sb)->data_start;
-	error = !b->cluster_size || !sector_mult;
-	if (!error) {
-		MSDOS_SB(sb)->clusters = b->cluster_size ? data_sectors/
-		    b->cluster_size/sector_mult : 0;
-		MSDOS_SB(sb)->fat_bits = fat ? fat : MSDOS_SB(sb)->clusters >
-		    MSDOS_FAT12 ? 16 : 12;
-		fat_clusters = MSDOS_SB(sb)->fat_length*SECTOR_SIZE*8/
-		    MSDOS_SB(sb)->fat_bits;
-		error = !MSDOS_SB(sb)->fats || (MSDOS_SB(sb)->dir_entries &
-		    (MSDOS_DPS-1)) || MSDOS_SB(sb)->clusters+2 > fat_clusters+
-		    MSDOS_MAX_EXTRA || (logical_sector_size & (SECTOR_SIZE-1))
-		    || !b->secs_track || !b->heads;
-	}
-	brelse(bh);
-	/*
-		This must be done after the brelse because the bh is a dummy
-		allocated by msdos_bread (see buffer.c)
-	*/
-	sb->s_blocksize = blksize;	/* Using this small block size solve the */
-				/* the misfit with buffer cache and cluster */
-				/* because cluster (DOS) are often aligned */
-				/* on odd sector */
-	sb->s_blocksize_bits = blksize == 512 ? 9 : 10;
-	if (error || debug) {
-		/* The MSDOS_CAN_BMAP is obsolete, but left just to remember */
-		printk("[MS-DOS FS Rel. 12,FAT %d,check=%c,conv=%c,"
-		    "uid=%d,gid=%d,umask=%03o%s]\n",MSDOS_SB(sb)->fat_bits,check,
-		    conversion,uid,gid,umask,MSDOS_CAN_BMAP(MSDOS_SB(sb)) ?
-		    ",bmap" : "");
-		printk("[me=0x%x,cs=%d,#f=%d,fs=%d,fl=%d,ds=%d,de=%d,data=%d,"
-		    "se=%d,ts=%ld,ls=%d]\n",b->media,MSDOS_SB(sb)->cluster_size,
-		    MSDOS_SB(sb)->fats,MSDOS_SB(sb)->fat_start,MSDOS_SB(sb)->
-		    fat_length,MSDOS_SB(sb)->dir_start,MSDOS_SB(sb)->dir_entries,
-		    MSDOS_SB(sb)->data_start,CF_LE_W(*(unsigned short *) &b->
-		    sectors),(unsigned long)b->total_sect,logical_sector_size);
-		printk ("Transaction block size = %d\n",blksize);
-	}
-	if (MSDOS_SB(sb)->clusters+2 > fat_clusters)
-		MSDOS_SB(sb)->clusters = fat_clusters-2;
-	if (error) {
-		if (!silent)
-			printk("VFS: Can't find a valid MSDOS filesystem on dev "
-			       "%s.\n", kdevname(sb->s_dev));
-		sb->s_dev = 0;
-		MOD_DEC_USE_COUNT;
-		return NULL;
-	}
-	sb->s_magic = MSDOS_SUPER_MAGIC;
-	MSDOS_SB(sb)->name_check = check;
-	MSDOS_SB(sb)->conversion = conversion;
-	/* set up enough so that it can read an inode */
-	sb->s_op = &msdos_sops;
-	MSDOS_SB(sb)->fs_uid = uid;
-	MSDOS_SB(sb)->fs_gid = gid;
-	MSDOS_SB(sb)->fs_umask = umask;
-	MSDOS_SB(sb)->quiet = quiet;
-	MSDOS_SB(sb)->dotsOK = dotsOK;
-	MSDOS_SB(sb)->free_clusters = -1; /* don't know yet */
-	MSDOS_SB(sb)->fat_wait = NULL;
-	MSDOS_SB(sb)->fat_lock = 0;
-	MSDOS_SB(sb)->prev_free = 0;
-	if (!(sb->s_mounted = iget(sb,MSDOS_ROOT_INO))) {
-		sb->s_dev = 0;
-		printk("get root inode failed\n");
-		MOD_DEC_USE_COUNT;
-		return NULL;
-	}
-	return sb;
-}
-
-
-void msdos_statfs(struct super_block *sb,struct statfs *buf, int bufsiz)
-{
-	int free,nr;
-	struct statfs tmp;
-
-	lock_fat(sb);
-	if (MSDOS_SB(sb)->free_clusters != -1)
-		free = MSDOS_SB(sb)->free_clusters;
-	else {
-		free = 0;
-		for (nr = 2; nr < MSDOS_SB(sb)->clusters+2; nr++)
-			if (!fat_access(sb,nr,-1)) free++;
-		MSDOS_SB(sb)->free_clusters = free;
-	}
-	unlock_fat(sb);
-	tmp.f_type = sb->s_magic;
-	tmp.f_bsize = MSDOS_SB(sb)->cluster_size*SECTOR_SIZE;
-	tmp.f_blocks = MSDOS_SB(sb)->clusters;
-	tmp.f_bfree = free;
-	tmp.f_bavail = free;
-	tmp.f_files = 0;
-	tmp.f_ffree = 0;
-	tmp.f_namelen = 12;
-	memcpy_tofs(buf, &tmp, bufsiz);
-}
-
-
-int msdos_bmap(struct inode *inode,int block)
-{
-	struct msdos_sb_info *sb;
-	int cluster,offset;
-
-	sb = MSDOS_SB(inode->i_sb);
-	if (inode->i_ino == MSDOS_ROOT_INO) {
-		return sb->dir_start + block;
-	}
-	cluster = block/sb->cluster_size;
-	offset = block % sb->cluster_size;
-	if (!(cluster = get_cluster(inode,cluster))) return 0;
-	return (cluster-2)*sb->cluster_size+sb->data_start+offset;
-}
-
-
-void msdos_read_inode(struct inode *inode)
-{
-	struct super_block *sb = inode->i_sb;
-	struct buffer_head *bh;
-	struct msdos_dir_entry *raw_entry;
-	int nr;
-
-/* printk("read inode %d\n",inode->i_ino); */
-	MSDOS_I(inode)->i_busy = 0;
-	MSDOS_I(inode)->i_depend = MSDOS_I(inode)->i_old = NULL;
-	MSDOS_I(inode)->i_binary = 1;
-	inode->i_uid = MSDOS_SB(inode->i_sb)->fs_uid;
-	inode->i_gid = MSDOS_SB(inode->i_sb)->fs_gid;
-	if (inode->i_ino == MSDOS_ROOT_INO) {
-		inode->i_mode = (S_IRWXUGO & ~MSDOS_SB(inode->i_sb)->fs_umask) |
-		    S_IFDIR;
-		inode->i_op = &msdos_dir_inode_operations;
-		inode->i_nlink = msdos_subdirs(inode)+2;
-		    /* subdirs (neither . nor ..) plus . and "self" */
-		inode->i_size = MSDOS_SB(inode->i_sb)->dir_entries*
-		    sizeof(struct msdos_dir_entry);
-		inode->i_blksize = MSDOS_SB(inode->i_sb)->cluster_size*
-		    SECTOR_SIZE;
-		inode->i_blocks = (inode->i_size+inode->i_blksize-1)/
-		    inode->i_blksize*MSDOS_SB(inode->i_sb)->cluster_size;
-		MSDOS_I(inode)->i_start = 0;
-		MSDOS_I(inode)->i_attrs = 0;
-		inode->i_mtime = inode->i_atime = inode->i_ctime = 0;
-		return;
-	}
-	if (!(bh = bread(inode->i_dev,inode->i_ino >> MSDOS_DPB_BITS,
-	    SECTOR_SIZE))) {
-		printk("dev = %s, ino = %ld\n",
-		       kdevname(inode->i_dev), inode->i_ino);
-		panic("msdos_read_inode: unable to read i-node block");
-	}
-	raw_entry = &((struct msdos_dir_entry *) (bh->b_data))
-	    [inode->i_ino & (MSDOS_DPB-1)];
-	if ((raw_entry->attr & ATTR_DIR) && !IS_FREE(raw_entry->name)) {
-		inode->i_mode = MSDOS_MKMODE(raw_entry->attr,S_IRWXUGO &
-		    ~MSDOS_SB(inode->i_sb)->fs_umask) | S_IFDIR;
-		inode->i_op = &msdos_dir_inode_operations;
-		MSDOS_I(inode)->i_start = CF_LE_W(raw_entry->start);
-		inode->i_nlink = msdos_subdirs(inode);
-		    /* includes .., compensating for "self" */
-#ifdef DEBUG
-		if (!inode->i_nlink) {
-			printk("directory %d: i_nlink == 0\n",inode->i_ino);
-			inode->i_nlink = 1;
-		}
-#endif
-		inode->i_size = 0;
-		if ((nr = CF_LE_W(raw_entry->start)) != 0)
-			while (nr != -1) {
-				inode->i_size += SECTOR_SIZE*MSDOS_SB(inode->
-				    i_sb)->cluster_size;
-				if (!(nr = fat_access(inode->i_sb,nr,-1))) {
-					printk("Directory %ld: bad FAT\n",
-					    inode->i_ino);
-					break;
-				}
-			}
-	} else { /* not a directory */
-		inode->i_mode = MSDOS_MKMODE(raw_entry->attr,
-		    (IS_NOEXEC(inode) ? S_IRUGO|S_IWUGO : S_IRWXUGO)
-		    & ~MSDOS_SB(inode->i_sb)->fs_umask) | S_IFREG;
-		inode->i_op = sb->s_blocksize == 1024
-			? &msdos_file_inode_operations_1024
-			: &msdos_file_inode_operations;
-		MSDOS_I(inode)->i_start = CF_LE_W(raw_entry->start);
-		inode->i_nlink = 1;
-		inode->i_size = CF_LE_L(raw_entry->size);
-	}
-	if(raw_entry->attr & ATTR_SYS)
-		inode->i_flags |= S_IMMUTABLE;
-	MSDOS_I(inode)->i_binary = is_binary(MSDOS_SB(inode->i_sb)->conversion,
-	    raw_entry->ext);
-	MSDOS_I(inode)->i_attrs = raw_entry->attr & ATTR_UNUSED;
-	/* this is as close to the truth as we can get ... */
-	inode->i_blksize = MSDOS_SB(inode->i_sb)->cluster_size*SECTOR_SIZE;
-	inode->i_blocks = (inode->i_size+inode->i_blksize-1)/
-	    inode->i_blksize*MSDOS_SB(inode->i_sb)->cluster_size;
-	inode->i_mtime = inode->i_atime = inode->i_ctime =
-	    date_dos2unix(CF_LE_W(raw_entry->time),CF_LE_W(raw_entry->date));
-	brelse(bh);
-}
-
-
-void msdos_write_inode(struct inode *inode)
-{
-	struct super_block *sb = inode->i_sb;
-	struct buffer_head *bh;
-	struct msdos_dir_entry *raw_entry;
-
-	inode->i_dirt = 0;
-	if (inode->i_ino == MSDOS_ROOT_INO || !inode->i_nlink) return;
-	if (!(bh = bread(inode->i_dev,inode->i_ino >> MSDOS_DPB_BITS,
-	    SECTOR_SIZE))) {
-		printk("dev = %s, ino = %ld\n",
-		       kdevname(inode->i_dev), inode->i_ino);
-		panic("msdos_write_inode: unable to read i-node block");
-	}
-	raw_entry = &((struct msdos_dir_entry *) (bh->b_data))
-	    [inode->i_ino & (MSDOS_DPB-1)];
-	if (S_ISDIR(inode->i_mode)) {
-		raw_entry->attr = ATTR_DIR;
-		raw_entry->size = 0;
-	}
-	else {
-		raw_entry->attr = ATTR_NONE;
-		raw_entry->size = CT_LE_L(inode->i_size);
-	}
-	raw_entry->attr |= MSDOS_MKATTR(inode->i_mode) |
-	    MSDOS_I(inode)->i_attrs;
-	raw_entry->start = CT_LE_L(MSDOS_I(inode)->i_start);
-	date_unix2dos(inode->i_mtime,&raw_entry->time,&raw_entry->date);
-	raw_entry->time = CT_LE_W(raw_entry->time);
-	raw_entry->date = CT_LE_W(raw_entry->date);
-	mark_buffer_dirty(bh, 1);
-	brelse(bh);
-}
-
-
-int msdos_notify_change(struct inode * inode,struct iattr * attr)
-{
-	int error;
-
-	error = inode_change_ok(inode, attr);
-	if (error)
-		return error;
-
-	if (((attr->ia_valid & ATTR_UID) && 
-	     (attr->ia_uid != MSDOS_SB(inode->i_sb)->fs_uid)) ||
-	    ((attr->ia_valid & ATTR_GID) && 
-	     (attr->ia_gid != MSDOS_SB(inode->i_sb)->fs_gid)) ||
-	    ((attr->ia_valid & ATTR_MODE) &&
-	     (attr->ia_mode & ~MSDOS_VALID_MODE)))
-		error = -EPERM;
-
-	if (error)
-		return MSDOS_SB(inode->i_sb)->quiet ? 0 : error;
-
-	inode_setattr(inode, attr);
-
-	if (IS_NOEXEC(inode) && !S_ISDIR(inode->i_mode))
-		inode->i_mode &= S_IFMT | S_IRUGO | S_IWUGO;
-	else
-		inode->i_mode |= S_IXUGO;
-
-	inode->i_mode = ((inode->i_mode & S_IFMT) | ((((inode->i_mode & S_IRWXU
-	    & ~MSDOS_SB(inode->i_sb)->fs_umask) | S_IRUSR) >> 6)*S_IXUGO)) &
-	    ~MSDOS_SB(inode->i_sb)->fs_umask;
-	return 0;
-}
-
-static struct symbol_table msdos_syms = {
-/* Should this be surrounded with "#ifdef CONFIG_MODULES" ? */
-#include <linux/symtab_begin.h>
-	/*
-	 * Support for umsdos fs
-	 *
-	 * These symbols are _always_ exported, in case someone
-	 * wants to install the umsdos module later.
-	 */
-	X(msdos_bmap),
-	X(msdos_create),
-	X(msdos_file_read),
-	X(msdos_file_write),
-	X(msdos_lookup),
-	X(msdos_mkdir),
-	X(msdos_mmap),
-	X(msdos_put_inode),
-	X(msdos_put_super),
-	X(msdos_read_inode),
-	X(msdos_read_super),
-	X(msdos_readdir),
-	X(msdos_rename),
-	X(msdos_rmdir),
-	X(msdos_smap),
-	X(msdos_statfs),
-	X(msdos_truncate),
-	X(msdos_unlink),
-	X(msdos_unlink_umsdos),
-	X(msdos_write_inode),
-#include <linux/symtab_end.h>
-};
-
-static struct file_system_type msdos_fs_type = {
-	msdos_read_super, "msdos", 1, NULL
-};
-
-int init_msdos_fs(void)
-{
-	int status;
-
-	if ((status = register_filesystem(&msdos_fs_type)) == 0)
-		status = register_symtab(&msdos_syms);
-	return status;
-}
-
-#ifdef MODULE
-int init_module(void)
-{
-	return init_msdos_fs();
-}
-
-void cleanup_module(void)
-{
-	unregister_filesystem(&msdos_fs_type);
-}
-
-#endif
-