patch-2.1.112 linux/fs/ufs/namei.c

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diff -u --recursive --new-file v2.1.111/linux/fs/ufs/namei.c linux/fs/ufs/namei.c
@@ -0,0 +1,1147 @@
+/*
+ * linux/fs/ufs/namei.c
+ *
+ * Copyright (C) 1998
+ * Daniel Pirkl <daniel.pirkl@email.cz>
+ * Charles University, Faculty of Mathematics and Physics
+ *
+ *  from
+ *
+ *  linux/fs/ext2/namei.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ *  from
+ *
+ *  linux/fs/minix/namei.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  Big-endian to little-endian byte-swapping/bitmaps by
+ *        David S. Miller (davem@caip.rutgers.edu), 1995
+ */
+
+#include <asm/uaccess.h>
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/ufs_fs.h>
+#include <linux/fcntl.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/locks.h>
+
+#include "swab.h"
+#include "util.h"
+
+#undef UFS_NAMEI_DEBUG
+
+#ifdef UFS_NAMEI_DEBUG
+#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
+#else
+#define UFSD(x)
+#endif
+
+/*
+ * define how far ahead to read directories while searching them.
+ */
+#define NAMEI_RA_CHUNKS  2
+#define NAMEI_RA_BLOCKS  4
+#define NAMEI_RA_SIZE        (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
+#define NAMEI_RA_INDEX(c,b)  (((c) * NAMEI_RA_BLOCKS) + (b))
+
+/*
+ * NOTE! unlike strncmp, ufs_match returns 1 for success, 0 for failure.
+ */
+static int ufs_match (int len, const char * const name,
+	struct ufs_dir_entry * de, unsigned flags, unsigned swab)
+{
+	if (!de || !SWAB32(de->d_ino) || len > UFS_MAXNAMLEN)
+		return 0;
+	/*
+	 * "" means "." ---> so paths like "/usr/lib//libc.a" work
+	 */
+	if (!len && ufs_namlen(de) == 1 && (de->d_name[0] == '.') &&
+	   (de->d_name[1] == '\0'))
+		return 1;
+	if (len != ufs_namlen(de))
+		return 0;
+	return !memcmp(name, de->d_name, len);
+}
+
+/*
+ *	ufs_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 * ufs_find_entry (struct inode * dir,
+	const char * const name, int namelen, struct ufs_dir_entry ** res_dir)
+{
+	struct super_block * sb;
+	struct buffer_head * bh_use[NAMEI_RA_SIZE];
+	struct buffer_head * bh_read[NAMEI_RA_SIZE];
+	unsigned long offset;
+	int block, toread, i, err;
+	unsigned flags, swab;
+
+	UFSD(("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen))
+	
+	*res_dir = NULL;
+	if (!dir) 
+		return NULL;
+	
+	sb = dir->i_sb;
+	flags = sb->u.ufs_sb.s_flags;
+	swab = sb->u.ufs_sb.s_swab;
+	
+	if (namelen > UFS_MAXNAMLEN)
+		return NULL;
+
+	memset (bh_use, 0, sizeof (bh_use));
+	toread = 0;
+	for (block = 0; block < NAMEI_RA_SIZE; ++block) {
+		struct buffer_head * bh;
+
+		if ((block << sb->s_blocksize_bits) >= dir->i_size)
+			break;
+		bh = ufs_getfrag (dir, block, 0, &err);
+		bh_use[block] = bh;
+		if (bh && !buffer_uptodate(bh))
+			bh_read[toread++] = bh;
+	}
+
+	for (block = 0, offset = 0; offset < dir->i_size; block++) {
+		struct buffer_head * bh;
+		struct ufs_dir_entry * de;
+		char * dlimit;
+
+		if ((block % NAMEI_RA_BLOCKS) == 0 && toread) {
+			ll_rw_block (READ, toread, bh_read);
+			toread = 0;
+		}
+		bh = bh_use[block % NAMEI_RA_SIZE];
+		if (!bh) {
+			ufs_error (sb, "ufs_find_entry",
+				"directory #%lu contains a hole at offset %lu", dir->i_ino, offset);
+			offset += sb->s_blocksize;
+			continue;
+		}
+		wait_on_buffer (bh);
+		if (!buffer_uptodate(bh)) {
+			/*
+			 * read error: all bets are off
+			 */
+			break;
+		}
+
+		de = (struct ufs_dir_entry *) bh->b_data;
+		dlimit = bh->b_data + sb->s_blocksize;
+		while ((char *) de < dlimit && offset < dir->i_size) {
+			if (!ufs_check_dir_entry ("ufs_find_entry", dir, de, bh, offset))
+				goto failed;
+			if (SWAB32(de->d_ino) != 0 && ufs_match (namelen, name, de, flags, swab)) {
+				for (i = 0; i < NAMEI_RA_SIZE; ++i) {
+					if (bh_use[i] != bh)
+						brelse (bh_use[i]);
+				}
+				*res_dir = de;
+				UFSD(("EXIT\n"))
+				return bh;
+			}
+			offset += SWAB16(de->d_reclen);
+			de = (struct ufs_dir_entry *)
+				((char *) de + SWAB16(de->d_reclen));
+		}
+
+		brelse (bh);
+		if (((block + NAMEI_RA_SIZE) << sb->s_blocksize_bits ) >=
+		    dir->i_size)
+			bh = NULL;
+		else
+			bh = ufs_getfrag (dir, block + NAMEI_RA_SIZE, 0, &err);
+		bh_use[block % NAMEI_RA_SIZE] = bh;
+		if (bh && !buffer_uptodate(bh))
+			bh_read[toread++] = bh;
+	}
+
+failed:
+	for (i = 0; i < NAMEI_RA_SIZE; ++i) brelse (bh_use[i]);
+	UFSD(("EXIT (FAILED)\n"))
+	return NULL;
+}
+
+int ufs_lookup(struct inode * dir, struct dentry *dentry)
+{
+	struct super_block * sb;
+	struct inode * inode;
+	struct ufs_dir_entry * de;
+	struct buffer_head * bh;
+	unsigned swab;
+	
+	UFSD(("ENTER\n"))
+	
+	sb = dir->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+	
+	if (dentry->d_name.len > UFS_MAXNAMLEN)
+		return -ENAMETOOLONG;
+
+	bh = ufs_find_entry (dir, dentry->d_name.name, dentry->d_name.len, &de);
+	inode = NULL;
+	if (bh) {
+		unsigned long ino = SWAB32(de->d_ino);
+		brelse (bh);
+		inode = iget(sb, ino);
+		if (!inode) 
+			return -EACCES;
+	}
+	d_add(dentry, inode);
+	UFSD(("EXIT\n"))
+	return 0;
+}
+
+/*
+ *	ufs_add_entry()
+ *
+ * adds a file entry to the specified directory, using the same
+ * semantics as ufs_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 * ufs_add_entry (struct inode * dir,
+	const char * name, int namelen, struct ufs_dir_entry ** res_dir, 
+	int *err )
+{
+	struct super_block * sb;
+	struct ufs_sb_private_info * uspi;
+	unsigned long offset;
+	unsigned fragoff;
+	unsigned short rec_len;
+	struct buffer_head * bh;
+	struct ufs_dir_entry * de, * de1;
+	unsigned flags, swab;
+
+	UFSD(("ENTER, name %s, namelen %u\n", name, namelen))
+	
+	*err = -EINVAL;
+	*res_dir = NULL;
+	if (!dir || !dir->i_nlink)
+		return NULL;
+		
+	sb = dir->i_sb;
+	flags = sb->u.ufs_sb.s_flags;
+	swab = sb->u.ufs_sb.s_swab;
+	uspi = sb->u.ufs_sb.s_uspi;
+
+	if (namelen > UFS_MAXNAMLEN)
+	{
+		*err = -ENAMETOOLONG;
+		return NULL;
+	}
+
+	if (!namelen)
+		return NULL;
+	/*
+	 * Is this a busy deleted directory?  Can't create new files if so
+	 */
+	if (dir->i_size == 0)
+	{
+		*err = -ENOENT;
+		return NULL;
+	}
+	bh = ufs_bread (dir, 0, 0, err);
+	if (!bh)
+		return NULL;
+	rec_len = UFS_DIR_REC_LEN(namelen);
+	offset = 0;
+	de = (struct ufs_dir_entry *) bh->b_data;
+	*err = -ENOSPC;
+	while (1) {
+		if ((char *)de >= SECTOR_SIZE + bh->b_data) {
+			fragoff = offset & ~uspi->s_fmask;
+			if (fragoff != 0 && fragoff != SECTOR_SIZE)
+				ufs_error (sb, "ufs_add_entry", "internal error"
+					" fragoff %u", fragoff);
+			if (!fragoff) {
+				brelse (bh);
+				bh = NULL;
+				bh = ufs_bread (dir, offset >> sb->s_blocksize_bits, 1, err);
+			}
+			if (!bh)
+				return NULL;
+			if (dir->i_size <= offset) {
+				if (dir->i_size == 0) {
+					*err = -ENOENT;
+					return NULL;
+				}
+				de = (struct ufs_dir_entry *) (bh->b_data + fragoff);
+				de->d_ino = SWAB32(0);
+				de->d_reclen = SWAB16(SECTOR_SIZE);
+				de->d_u.d_namlen = SWAB16(0);
+				dir->i_size = offset + SECTOR_SIZE;
+				mark_inode_dirty(dir);
+			} else {
+				de = (struct ufs_dir_entry *) bh->b_data;
+			}
+		}
+		if (!ufs_check_dir_entry ("ufs_add_entry", dir, de, bh, offset)) {
+			*err = -ENOENT;
+			brelse (bh);
+			return NULL;
+		}
+		if (SWAB32(de->d_ino) != 0 && ufs_match (namelen, name, de, flags, swab)) {
+				*err = -EEXIST;
+				brelse (bh);
+				return NULL;
+		}
+		if ((SWAB32(de->d_ino) == 0 && SWAB16(de->d_reclen) >= rec_len) ||
+		    (SWAB16(de->d_reclen) >= UFS_DIR_REC_LEN(SWAB16(de->d_u.d_namlen)) + rec_len)) {
+			offset += SWAB16(de->d_reclen);
+			if (SWAB32(de->d_ino)) {
+				de1 = (struct ufs_dir_entry *) ((char *) de +
+					UFS_DIR_REC_LEN(SWAB16(de->d_u.d_namlen)));
+				de1->d_reclen = SWAB16(SWAB16(de->d_reclen) -
+					UFS_DIR_REC_LEN(SWAB16(de->d_u.d_namlen)));
+				de->d_reclen = SWAB16(UFS_DIR_REC_LEN(SWAB16(de->d_u.d_namlen)));
+				de = de1;
+			}
+			de->d_ino = SWAB32(0);
+			de->d_u.d_namlen = SWAB16(namelen);
+			memcpy (de->d_name, name, namelen + 1);
+			/*
+			 * XXX shouldn't update any times until successful
+			 * completion of syscall, but too many callers depend
+			 * on this.
+			 *
+			 * XXX similarly, too many callers depend on
+			 * ufs_new_inode() setting the times, but error
+			 * recovery deletes the inode, so the worst that can
+			 * happen is that the times are slightly out of date
+			 * and/or different from the directory change time.
+			 */
+			dir->i_mtime = dir->i_ctime = CURRENT_TIME;
+			mark_inode_dirty(dir);
+			dir->i_version = ++event;
+			mark_buffer_dirty(bh, 1);
+			*res_dir = de;
+			*err = 0;
+			
+			UFSD(("EXIT\n"))
+			return bh;
+		}
+		offset += SWAB16(de->d_reclen);
+		de = (struct ufs_dir_entry *) ((char *) de + SWAB16(de->d_reclen));
+	}
+	brelse (bh);
+	UFSD(("EXIT (FAILED)\n"))
+	return NULL;
+}
+
+/*
+ * ufs_delete_entry deletes a directory entry by merging it with the
+ * previous entry.
+ */
+static int ufs_delete_entry (struct inode * inode, struct ufs_dir_entry * dir,
+	struct buffer_head * bh )
+	
+{
+	struct super_block * sb;
+	struct ufs_dir_entry * de, * pde;
+	unsigned i;
+	unsigned flags, swab;
+	
+	UFSD(("ENTER\n"))
+
+	sb = inode->i_sb;
+	flags = sb->u.ufs_sb.s_flags;
+	swab = sb->u.ufs_sb.s_swab;
+	i = 0;
+	pde = NULL;
+	de = (struct ufs_dir_entry *) bh->b_data;
+	
+	UFSD(("ino %u, reclen %u, namlen %u, name %s\n", SWAB32(de->d_ino),
+		SWAB16(de->d_reclen), ufs_namlen(de), de->d_name))
+
+	while (i < bh->b_size) {
+		if (!ufs_check_dir_entry ("ufs_delete_entry", inode, de, bh, i))
+			return -EIO;
+		if (de == dir)  {
+			if (pde)
+				pde->d_reclen =
+				    SWAB16(SWAB16(pde->d_reclen) +
+				    SWAB16(dir->d_reclen));
+			dir->d_ino = SWAB32(0);
+			UFSD(("EXIT\n"))
+			return 0;
+		}
+		i += SWAB16(de->d_reclen);
+		if (i == SECTOR_SIZE) pde = NULL;
+		else pde = de;
+		de = (struct ufs_dir_entry *)
+		    ((char *) de + SWAB16(de->d_reclen));
+		if (i == SECTOR_SIZE && SWAB16(de->d_reclen) == 0)
+			break;
+	}
+	UFSD(("EXIT\n"))
+	return -ENOENT;
+}
+
+/*
+ * By the time this is called, we already have created
+ * the directory cache entry for the new file, but it
+ * is so far negative - it has no inode.
+ *
+ * If the create succeeds, we fill in the inode information
+ * with d_instantiate(). 
+ */
+int ufs_create (struct inode * dir, struct dentry * dentry, int mode)
+{
+	struct super_block * sb;
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct ufs_dir_entry * de;
+	int err = -EIO;
+	unsigned swab;
+	
+	sb = dir->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+
+	/*
+	 * N.B. Several error exits in ufs_new_inode don't set err.
+	 */
+	UFSD(("ENTER\n"))
+	
+	inode = ufs_new_inode (dir, mode, &err);
+	if (!inode)
+		return err;
+	inode->i_op = &ufs_file_inode_operations;
+	inode->i_mode = mode;
+	mark_inode_dirty(inode);
+	bh = ufs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
+	if (!bh) {
+		inode->i_nlink--;
+		mark_inode_dirty(inode);
+		iput (inode);
+		return err;
+	}
+	de->d_ino = SWAB32(inode->i_ino);
+	dir->i_version = ++event;
+	mark_buffer_dirty(bh, 1);
+	if (IS_SYNC(dir)) {
+		ll_rw_block (WRITE, 1, &bh);
+		wait_on_buffer (bh);
+	}
+	brelse (bh);
+	d_instantiate(dentry, inode);
+	
+	UFSD(("EXIT\n"))
+	
+	return 0;
+}
+
+int ufs_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
+{
+	struct super_block * sb;
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct ufs_dir_entry * de;
+	int err = -EIO;
+	unsigned swab;
+	
+	sb = dir->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+	
+	err = -ENAMETOOLONG;
+	if (dentry->d_name.len > UFS_MAXNAMLEN)
+		goto out;
+
+	inode = ufs_new_inode (dir, mode, &err);
+	if (!inode)
+		goto out;
+
+	inode->i_uid = current->fsuid;
+	inode->i_mode = mode;
+	inode->i_op = NULL;
+	if (S_ISREG(inode->i_mode))
+		inode->i_op = &ufs_file_inode_operations;
+	else if (S_ISDIR(inode->i_mode)) {
+		inode->i_op = &ufs_dir_inode_operations;
+		if (dir->i_mode & S_ISGID)
+			inode->i_mode |= S_ISGID;
+	}
+	else if (S_ISLNK(inode->i_mode))
+		inode->i_op = &ufs_symlink_inode_operations;
+	else if (S_ISCHR(inode->i_mode))
+		inode->i_op = &chrdev_inode_operations;
+	else if (S_ISBLK(inode->i_mode))
+		inode->i_op = &blkdev_inode_operations;
+	else if (S_ISFIFO(inode->i_mode)) 
+		init_fifo(inode);
+	if (S_ISBLK(mode) || S_ISCHR(mode))
+		inode->i_rdev = to_kdev_t(rdev);
+	mark_inode_dirty(inode);
+	bh = ufs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
+	if (!bh)
+		goto out_no_entry;
+	de->d_ino = SWAB32(inode->i_ino);
+	dir->i_version = ++event;
+	mark_buffer_dirty(bh, 1);
+	if (IS_SYNC(dir)) {
+		ll_rw_block (WRITE, 1, &bh);
+		wait_on_buffer (bh);
+	}
+	d_instantiate(dentry, inode);
+	brelse(bh);
+	err = 0;
+out:
+	return err;
+
+out_no_entry:
+	inode->i_nlink--;
+	mark_inode_dirty(inode);
+	iput(inode);
+	goto out;
+}
+
+int ufs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
+{
+	struct super_block * sb;
+	struct inode * inode;
+	struct buffer_head * bh, * dir_block;
+	struct ufs_dir_entry * de;
+	int err;
+	unsigned swab;
+	
+	sb = dir->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+	
+	err = -ENAMETOOLONG;
+	if (dentry->d_name.len > UFS_MAXNAMLEN)
+		goto out;
+
+	err = -EMLINK;
+	if (dir->i_nlink >= UFS_LINK_MAX)
+		goto out;
+	err = -EIO;
+	inode = ufs_new_inode (dir, S_IFDIR, &err);
+	if (!inode)
+		goto out;
+
+	inode->i_op = &ufs_dir_inode_operations;
+	inode->i_size = SECTOR_SIZE;
+	dir_block = ufs_bread (inode, 0, 1, &err);
+	if (!dir_block) {
+		inode->i_nlink--; /* is this nlink == 0? */
+		mark_inode_dirty(inode);
+		iput (inode);
+		return err;
+	}
+	inode->i_blocks = sb->s_blocksize / SECTOR_SIZE;
+	de = (struct ufs_dir_entry *) dir_block->b_data;
+	de->d_ino = SWAB32(inode->i_ino);
+	de->d_u.d_namlen = SWAB16(1);
+	de->d_reclen = SWAB16(UFS_DIR_REC_LEN(1));
+	strcpy (de->d_name, ".");
+	de = (struct ufs_dir_entry *) ((char *) de + SWAB16(de->d_reclen));
+	de->d_ino = SWAB32(dir->i_ino);
+	de->d_reclen = SWAB16(SECTOR_SIZE - UFS_DIR_REC_LEN(1));
+	de->d_u.d_namlen = SWAB16(2);
+	strcpy (de->d_name, "..");
+	inode->i_nlink = 2;
+	mark_buffer_dirty(dir_block, 1);
+	brelse (dir_block);
+	inode->i_mode = S_IFDIR | (mode & (S_IRWXUGO|S_ISVTX) & ~current->fs->umask);
+	if (dir->i_mode & S_ISGID)
+		inode->i_mode |= S_ISGID;
+	mark_inode_dirty(inode);
+	bh = ufs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
+	if (!bh)
+		goto out_no_entry;
+	de->d_ino = SWAB32(inode->i_ino);
+	dir->i_version = ++event;
+	mark_buffer_dirty(bh, 1);
+	if (IS_SYNC(dir)) {
+		ll_rw_block (WRITE, 1, &bh);
+		wait_on_buffer (bh);
+	}
+	dir->i_nlink++;
+	mark_inode_dirty(dir);
+	d_instantiate(dentry, inode);
+	brelse (bh);
+	err = 0;
+out:
+	return err;
+
+out_no_entry:
+	inode->i_nlink = 0;
+	mark_inode_dirty(inode);
+	iput (inode);
+	goto out;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ */
+static int ufs_empty_dir (struct inode * inode)
+{
+	struct super_block * sb;
+	unsigned long offset;
+	struct buffer_head * bh;
+	struct ufs_dir_entry * de, * de1;
+	int err;
+	unsigned swab;	
+	
+	sb = inode->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+
+	if (inode->i_size < UFS_DIR_REC_LEN(1) + UFS_DIR_REC_LEN(2) ||
+	    !(bh = ufs_bread (inode, 0, 0, &err))) {
+	    	ufs_warning (inode->i_sb, "empty_dir",
+			      "bad directory (dir #%lu) - no data block",
+			      inode->i_ino);
+		return 1;
+	}
+	de = (struct ufs_dir_entry *) bh->b_data;
+	de1 = (struct ufs_dir_entry *) ((char *) de + SWAB16(de->d_reclen));
+	if (SWAB32(de->d_ino) != inode->i_ino || !SWAB32(de1->d_ino) || 
+	    strcmp (".", de->d_name) || strcmp ("..", de1->d_name)) {
+	    	ufs_warning (inode->i_sb, "empty_dir",
+			      "bad directory (dir #%lu) - no `.' or `..'",
+			      inode->i_ino);
+		return 1;
+	}
+	offset = SWAB16(de->d_reclen) + SWAB16(de1->d_reclen);
+	de = (struct ufs_dir_entry *) ((char *) de1 + SWAB16(de1->d_reclen));
+	while (offset < inode->i_size ) {
+		if (!bh || (void *) de >= (void *) (bh->b_data + sb->s_blocksize)) {
+			brelse (bh);
+			bh = ufs_bread (inode, offset >> sb->s_blocksize_bits, 1, &err);
+	 		if (!bh) {
+				ufs_error (sb, "empty_dir",
+					    "directory #%lu contains a hole at offset %lu",
+					    inode->i_ino, offset);
+				offset += sb->s_blocksize;
+				continue;
+			}
+			de = (struct ufs_dir_entry *) bh->b_data;
+		}
+		if (!ufs_check_dir_entry ("empty_dir", inode, de, bh, offset)) {
+			brelse (bh);
+			return 1;
+		}
+		if (SWAB32(de->d_ino)) {
+			brelse (bh);
+			return 0;
+		}
+		offset += SWAB16(de->d_reclen);
+		de = (struct ufs_dir_entry *) ((char *) de + SWAB16(de->d_reclen));
+	}
+	brelse (bh);
+	return 1;
+}
+
+int ufs_rmdir (struct inode * dir, struct dentry *dentry)
+{
+	struct super_block *sb;
+	int retval;
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct ufs_dir_entry * de;
+	unsigned swab;
+	
+	sb = dir->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+		
+	UFSD(("ENTER\n"))
+	
+	retval = -ENAMETOOLONG;
+	if (dentry->d_name.len > UFS_MAXNAMLEN)
+		goto out;
+
+	retval = -ENOENT;
+	bh = ufs_find_entry (dir, dentry->d_name.name, dentry->d_name.len, &de);
+	if (!bh)
+		goto end_rmdir;
+
+	inode = dentry->d_inode;
+	if (inode->i_sb->dq_op)
+		inode->i_sb->dq_op->initialize (inode, -1);
+
+	retval = -EPERM;
+	if ((dir->i_mode & S_ISVTX) && 
+	    current->fsuid != inode->i_uid &&
+	    current->fsuid != dir->i_uid && !fsuser())
+		goto end_rmdir;
+	if (inode == dir)	/* we may not delete ".", but "../dir" is ok */
+		goto end_rmdir;
+
+	retval = -ENOTDIR;
+	if (!S_ISDIR(inode->i_mode))
+		goto end_rmdir;
+
+	retval = -EIO;
+	if (inode->i_dev != dir->i_dev)
+		goto end_rmdir;
+	if (SWAB32(de->d_ino) != inode->i_ino)
+		goto end_rmdir;
+
+	down(&inode->i_sem);
+	/*
+	 * Prune any child dentries so that this dentry becomes negative.
+	 */
+	if (dentry->d_count > 1) {
+		ufs_warning (sb, "ufs_rmdir", "d_count=%d, pruning\n", dentry->d_count);
+		shrink_dcache_parent(dentry);
+	}
+	if (!ufs_empty_dir (inode))
+		retval = -ENOTEMPTY;
+	else if (SWAB32(de->d_ino) != inode->i_ino)
+		retval = -ENOENT;
+	else {
+		if (dentry->d_count > 1) {
+		/*
+		 * Are we deleting the last instance of a busy directory?
+		 * Better clean up if so.
+		 *
+		 * Make directory empty (it will be truncated when finally
+		 * dereferenced).  This also inhibits ufs_add_entry.
+		 */
+			inode->i_size = 0;
+		}
+		retval = ufs_delete_entry (dir, de, bh);
+		dir->i_version = ++event;
+	}
+	up(&inode->i_sem);
+	if (retval)
+		goto end_rmdir;
+	mark_buffer_dirty(bh, 1);
+	if (IS_SYNC(dir)) {
+		ll_rw_block (WRITE, 1, &bh);
+		wait_on_buffer (bh);
+	}
+	if (inode->i_nlink != 2)
+		ufs_warning (inode->i_sb, "ufs_rmdir",
+			      "empty directory has nlink!=2 (%d)",
+			      inode->i_nlink);
+	inode->i_version = ++event;
+	inode->i_nlink = 0;
+	mark_inode_dirty(inode);
+	dir->i_nlink--;
+	inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+	mark_inode_dirty(dir);
+	d_delete(dentry);
+
+end_rmdir:
+	brelse (bh);
+out:
+	UFSD(("EXIT\n"))
+	
+	return retval;
+}
+
+int ufs_unlink(struct inode * dir, struct dentry *dentry)
+{
+	struct super_block * sb;
+	int retval;
+	struct inode * inode;
+	struct buffer_head * bh;
+	struct ufs_dir_entry * de;
+	unsigned flags, swab;
+
+	sb = dir->i_sb;
+	flags = sb->u.ufs_sb.s_flags;
+	swab = sb->u.ufs_sb.s_swab;
+		
+	retval = -ENAMETOOLONG;
+	if (dentry->d_name.len > UFS_MAXNAMLEN)
+		goto out;
+
+	retval = -ENOENT;
+	bh = ufs_find_entry (dir, dentry->d_name.name, dentry->d_name.len, &de);
+	UFSD(("de: ino %u, reclen %u, namelen %u, name %s\n", SWAB32(de->d_ino),
+		SWAB16(de->d_reclen), ufs_namlen(de), de->d_name))
+	if (!bh)
+		goto end_unlink;
+
+	inode = dentry->d_inode;
+	if (inode->i_sb->dq_op)
+		inode->i_sb->dq_op->initialize (inode, -1);
+
+	retval = -EPERM;
+	if (S_ISDIR(inode->i_mode))
+		goto end_unlink;
+	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+		goto end_unlink;
+	if ((dir->i_mode & S_ISVTX) &&
+	    current->fsuid != inode->i_uid &&
+	    current->fsuid != dir->i_uid && !fsuser())
+		goto end_unlink;
+
+	retval = -EIO;
+	if (SWAB32(de->d_ino) != inode->i_ino)
+		goto end_unlink;
+	
+	if (!inode->i_nlink) {
+		ufs_warning (inode->i_sb, "ufs_unlink",
+			      "Deleting nonexistent file (%lu), %d",
+			      inode->i_ino, inode->i_nlink);
+		inode->i_nlink = 1;
+	}
+	retval = ufs_delete_entry (dir, de, bh);
+	if (retval)
+		goto end_unlink;
+	dir->i_version = ++event;
+	mark_buffer_dirty(bh, 1);
+	if (IS_SYNC(dir)) {
+		ll_rw_block (WRITE, 1, &bh);
+		wait_on_buffer (bh);
+	}
+	dir->i_ctime = dir->i_mtime = CURRENT_TIME;
+	mark_inode_dirty(dir);
+	inode->i_nlink--;
+	mark_inode_dirty(inode);
+	inode->i_ctime = dir->i_ctime;
+	retval = 0;
+	d_delete(dentry);	/* This also frees the inode */
+
+end_unlink:
+	brelse (bh);
+out:
+	return retval;
+}
+
+
+int ufs_link (struct dentry * old_dentry, struct inode * dir,
+	struct dentry *dentry)
+{
+	struct super_block * sb;
+	struct inode *inode = old_dentry->d_inode;
+	struct ufs_dir_entry * de;
+	struct buffer_head * bh;
+	int err;
+	unsigned swab;
+
+	inode = old_dentry->d_inode;
+	sb = inode->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+	
+	if (S_ISDIR(inode->i_mode))
+		return -EPERM;
+
+	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+		return -EPERM;
+
+	if (inode->i_nlink >= UFS_LINK_MAX)
+		return -EMLINK;
+
+	bh = ufs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
+	if (!bh)
+		return err;
+
+	de->d_ino = SWAB32(inode->i_ino);
+	dir->i_version = ++event;
+	mark_buffer_dirty(bh, 1);
+	if (IS_SYNC(dir)) {
+		ll_rw_block (WRITE, 1, &bh);
+		wait_on_buffer (bh);
+	}
+	brelse (bh);
+	inode->i_nlink++;
+	inode->i_ctime = CURRENT_TIME;
+	mark_inode_dirty(inode);
+	inode->i_count++;
+	d_instantiate(dentry, inode);
+	return 0;
+}
+
+/*
+ * Create symbolic link. We use only slow symlinks at this time.
+ */
+int ufs_symlink (struct inode * dir, struct dentry * dentry,
+	const char * symname)
+{
+	struct super_block * sb;
+	struct ufs_dir_entry * de;
+	struct inode * inode;
+	struct buffer_head * bh, * name_block;
+	char * link;
+	unsigned i, l;
+	int err;
+	char c;
+	unsigned swab;
+	
+	UFSD(("ENTER\n"))
+	
+	sb = dir->i_sb;
+	swab = sb->u.ufs_sb.s_swab;
+	bh = name_block = NULL;
+	err = -EIO;
+	
+	if (!(inode = ufs_new_inode (dir, S_IFLNK, &err))) {
+		return err;
+	}
+	inode->i_mode = S_IFLNK | S_IRWXUGO;
+	inode->i_op = &ufs_symlink_inode_operations;
+	for (l = 0; l < sb->s_blocksize - 1 && symname [l]; l++);
+
+	/***if (l >= sizeof (inode->u.ufs_i.i_data)) {***/
+	if (1) {
+		/* slow symlink */
+		name_block = ufs_bread (inode, 0, 1, &err);
+		if (!name_block) {
+			inode->i_nlink--;
+			mark_inode_dirty(inode);
+			iput (inode);
+			return err;
+		}
+		link = name_block->b_data;
+		
+	} else {
+		/* fast symlink */
+		link = (char *) inode->u.ufs_i.i_u1.i_data;
+	}
+	i = 0;
+	while (i < sb->s_blocksize - 1 && (c = *(symname++)))
+		link[i++] = c;
+	link[i] = 0;
+	if (name_block) {
+		mark_buffer_dirty(name_block, 1);
+		brelse (name_block);
+	}
+	inode->i_size = i;
+	mark_inode_dirty(inode);
+
+	bh = ufs_add_entry (dir, dentry->d_name.name, dentry->d_name.len, &de, &err);
+	if (!bh)
+		goto out_no_entry;
+	de->d_ino = SWAB32(inode->i_ino);
+	dir->i_version = ++event;
+	mark_buffer_dirty(bh, 1);
+	if (IS_SYNC(dir)) {
+		ll_rw_block (WRITE, 1, &bh);
+		wait_on_buffer (bh);
+	}
+	brelse (bh);
+	d_instantiate(dentry, inode);
+	err = 0;
+out:
+	return err;
+
+out_no_entry:
+	inode->i_nlink--;
+	mark_inode_dirty(inode);
+	iput (inode);
+	goto out;
+}
+
+
+#define PARENT_INO(buffer) \
+	((struct ufs_dir_entry *) ((char *) buffer + \
+	SWAB16(((struct ufs_dir_entry *) buffer)->d_reclen)))->d_ino
+/*
+ * 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_ufs_rename (struct inode * old_dir, struct dentry * old_dentry,
+	struct inode * new_dir,	struct dentry * new_dentry )
+{
+	struct super_block * sb;
+	struct inode * old_inode, * new_inode;
+	struct buffer_head * old_bh, * new_bh, * dir_bh;
+	struct ufs_dir_entry * old_de, * new_de;
+	int retval;
+	unsigned flags, swab;
+	
+	sb = old_dir->i_sb;
+	flags = sb->u.ufs_sb.s_flags;
+	swab = sb->u.ufs_sb.s_swab;
+
+	UFSD(("ENTER\n"))
+	
+	old_inode = new_inode = NULL;
+	old_bh = new_bh = dir_bh = NULL;
+	new_de = NULL;
+	retval = -ENAMETOOLONG;
+	if (old_dentry->d_name.len > UFS_MAXNAMLEN)
+		goto end_rename;
+
+	UFSD(("name %s, len %u\n", old_dentry->d_name.name, old_dentry->d_name.len)) 
+	old_bh = ufs_find_entry (old_dir, old_dentry->d_name.name, old_dentry->d_name.len, &old_de);
+	UFSD(("ino %u, reclen %u, namlen %u, name %s\n", SWAB32(old_de->d_ino),
+		SWAB16(old_de->d_reclen), ufs_namlen(old_de), old_de->d_name))
+	    
+	retval = -ENOENT;
+	if (!old_bh)
+		goto end_rename;
+	old_inode = old_dentry->d_inode;
+
+	retval = -EPERM;
+	if ((old_dir->i_mode & S_ISVTX) && 
+	    current->fsuid != old_inode->i_uid &&
+	    current->fsuid != old_dir->i_uid && !fsuser())
+		goto end_rename;
+	if (IS_APPEND(old_inode) || IS_IMMUTABLE(old_inode))
+		goto end_rename;
+
+	new_inode = new_dentry->d_inode;
+	UFSD(("name %s, len %u\n", new_dentry->d_name.name, new_dentry->d_name.len)) 
+	new_bh = ufs_find_entry (new_dir, new_dentry->d_name.name, new_dentry->d_name.len, &new_de);
+	if (new_bh) {
+		if (!new_inode) {
+			brelse (new_bh);
+			new_bh = NULL;
+		} else {
+			if (new_inode->i_sb->dq_op)
+				new_inode->i_sb->dq_op->initialize (new_inode, -1);
+		}
+	}
+	retval = 0;
+	if (new_inode == old_inode)
+		goto end_rename;
+	if (new_inode && S_ISDIR(new_inode->i_mode)) {
+		retval = -EISDIR;
+		if (!S_ISDIR(old_inode->i_mode))
+			goto end_rename;
+		retval = -EINVAL;
+		if (is_subdir(new_dentry, old_dentry))
+			goto end_rename;
+		retval = -ENOTEMPTY;
+		if (!ufs_empty_dir (new_inode))
+			goto end_rename;
+		retval = -EBUSY;
+		if (new_dentry->d_count > 1)
+			goto end_rename;
+	}
+	retval = -EPERM;
+	if (new_inode) {
+		if ((new_dir->i_mode & S_ISVTX) &&
+		    current->fsuid != new_inode->i_uid &&
+		    current->fsuid != new_dir->i_uid && !fsuser())
+			goto end_rename;
+		if (IS_APPEND(new_inode) || IS_IMMUTABLE(new_inode))
+			goto end_rename;
+	}
+	if (S_ISDIR(old_inode->i_mode)) {
+		retval = -ENOTDIR;
+		if (new_inode && !S_ISDIR(new_inode->i_mode))
+			goto end_rename;
+		retval = -EINVAL;
+		if (is_subdir(new_dentry, old_dentry))
+			goto end_rename;
+		dir_bh = ufs_bread (old_inode, 0, 0, &retval);
+		if (!dir_bh)
+			goto end_rename;
+		if (SWAB32(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
+			goto end_rename;
+		retval = -EMLINK;
+		if (!new_inode && new_dir->i_nlink >= UFS_LINK_MAX)
+			goto end_rename;
+	}
+
+	if (!new_bh)
+		new_bh = ufs_add_entry (new_dir, new_dentry->d_name.name, new_dentry->d_name.len, &new_de,
+					 &retval);
+	if (!new_bh)
+		goto end_rename;
+	new_dir->i_version = ++event;
+
+	/*
+	 * ok, that's it
+	 */
+	new_de->d_ino = SWAB32(old_inode->i_ino);
+	ufs_delete_entry (old_dir, old_de, old_bh);
+
+	old_dir->i_version = ++event;
+	if (new_inode) {
+		new_inode->i_nlink--;
+		new_inode->i_ctime = CURRENT_TIME;
+		mark_inode_dirty(new_inode);
+	}
+	old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME;
+	mark_inode_dirty(old_dir);
+	if (dir_bh) {
+		PARENT_INO(dir_bh->b_data) = SWAB32(new_dir->i_ino);
+		mark_buffer_dirty(dir_bh, 1);
+		old_dir->i_nlink--;
+		mark_inode_dirty(old_dir);
+		if (new_inode) {
+			new_inode->i_nlink--;
+			mark_inode_dirty(new_inode);
+		} else {
+			new_dir->i_nlink++;
+			mark_inode_dirty(new_dir);
+		}
+	}
+	mark_buffer_dirty(old_bh,  1);
+	if (IS_SYNC(old_dir)) {
+		ll_rw_block (WRITE, 1, &old_bh);
+		wait_on_buffer (old_bh);
+	}
+	
+	mark_buffer_dirty(new_bh, 1);
+	if (IS_SYNC(new_dir)) {
+		ll_rw_block (WRITE, 1, &new_bh);
+		wait_on_buffer (new_bh);
+	}
+
+	/* Update the dcache */
+	d_move(old_dentry, new_dentry);
+	retval = 0;
+end_rename:
+	brelse (dir_bh);
+	brelse (old_bh);
+	brelse (new_bh);
+	
+	UFSD(("EXIT\n"))
+	
+	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.
+ *
+ * In the second extended file system, we use a lock flag stored in the memory
+ * super-block.  This way, we really lock other renames only if they occur
+ * on the same file system
+ */
+int ufs_rename (struct inode * old_dir, struct dentry *old_dentry,
+	struct inode * new_dir,	struct dentry *new_dentry )
+{
+	int result;
+
+	UFSD(("ENTER\n"))
+	
+	while (old_dir->i_sb->u.ufs_sb.s_rename_lock)
+		sleep_on (&old_dir->i_sb->u.ufs_sb.s_rename_wait);
+	old_dir->i_sb->u.ufs_sb.s_rename_lock = 1;
+	result = do_ufs_rename (old_dir, old_dentry, new_dir, new_dentry);
+	old_dir->i_sb->u.ufs_sb.s_rename_lock = 0;
+	wake_up (&old_dir->i_sb->u.ufs_sb.s_rename_wait);
+	
+	UFSD(("EXIT\n"))
+	
+	return result;
+}
+
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov