1 files changed, 627 insertions, 0 deletions

diff --git a/fs/ufs/dir.c b/fs/ufs/dir.c
new file mode 100644
index 0000000..d0915fb
--- /dev/null
+++ b/fs/ufs/dir.c
@@ -0,0 +1,627 @@
+/*
+ *  linux/fs/ufs/ufs_dir.c
+ *
+ * Copyright (C) 1996
+ * Adrian Rodriguez (adrian@franklins-tower.rutgers.edu)
+ * Laboratory for Computer Science Research Computing Facility
+ * Rutgers, The State University of New Jersey
+ *
+ * swab support by Francois-Rene Rideau <fare@tunes.org> 19970406
+ *
+ * 4.4BSD (FreeBSD) support added on February 1st 1998 by
+ * Niels Kristian Bech Jensen <nkbj@image.dk> partially based
+ * on code by Martin von Loewis <martin@mira.isdn.cs.tu-berlin.de>.
+ */
+
+#include <linux/time.h>
+#include <linux/fs.h>
+#include <linux/ufs_fs.h>
+#include <linux/smp_lock.h>
+#include <linux/buffer_head.h>
+#include <linux/sched.h>
+
+#include "swab.h"
+#include "util.h"
+
+#undef UFS_DIR_DEBUG
+
+#ifdef UFS_DIR_DEBUG
+#define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
+#else
+#define UFSD(x)
+#endif
+
+static int
+ufs_check_dir_entry (const char *, struct inode *, struct ufs_dir_entry *,
+		     struct buffer_head *, unsigned long);
+
+
+/*
+ * NOTE! unlike strncmp, ufs_match returns 1 for success, 0 for failure.
+ *
+ * len <= UFS_MAXNAMLEN and de != NULL are guaranteed by caller.
+ */
+static inline int ufs_match(struct super_block *sb, int len,
+		const char * const name, struct ufs_dir_entry * de)
+{
+	if (len != ufs_get_de_namlen(sb, de))
+		return 0;
+	if (!de->d_ino)
+		return 0;
+	return !memcmp(name, de->d_name, len);
+}
+
+/*
+ * This is blatantly stolen from ext2fs
+ */
+static int
+ufs_readdir (struct file * filp, void * dirent, filldir_t filldir)
+{
+	struct inode *inode = filp->f_dentry->d_inode;
+	int error = 0;
+	unsigned long offset, lblk;
+	int i, stored;
+	struct buffer_head * bh;
+	struct ufs_dir_entry * de;
+	struct super_block * sb;
+	int de_reclen;
+	unsigned flags;
+	u64     blk= 0L;
+
+	lock_kernel();
+
+	sb = inode->i_sb;
+	flags = UFS_SB(sb)->s_flags;
+
+	UFSD(("ENTER, ino %lu  f_pos %lu\n", inode->i_ino, (unsigned long) filp->f_pos))
+
+	stored = 0;
+	bh = NULL;
+	offset = filp->f_pos & (sb->s_blocksize - 1);
+
+	while (!error && !stored && filp->f_pos < inode->i_size) {
+		lblk = (filp->f_pos) >> sb->s_blocksize_bits;
+		blk = ufs_frag_map(inode, lblk);
+		if (!blk || !(bh = sb_bread(sb, blk))) {
+			/* XXX - error - skip to the next block */
+			printk("ufs_readdir: "
+			       "dir inode %lu has a hole at offset %lu\n",
+			       inode->i_ino, (unsigned long int)filp->f_pos);
+			filp->f_pos += sb->s_blocksize - offset;
+			continue;
+		}
+
+revalidate:
+		/* If the dir block has changed since the last call to
+		 * readdir(2), then we might be pointing to an invalid
+		 * dirent right now.  Scan from the start of the block
+		 * to make sure. */
+		if (filp->f_version != inode->i_version) {
+			for (i = 0; i < sb->s_blocksize && i < offset; ) {
+				de = (struct ufs_dir_entry *)(bh->b_data + i);
+				/* It's too expensive to do a full
+				 * dirent test each time round this
+				 * loop, but we do have to test at
+				 * least that it is non-zero.  A
+				 * failure will be detected in the
+				 * dirent test below. */
+				de_reclen = fs16_to_cpu(sb, de->d_reclen);
+				if (de_reclen < 1)
+					break;
+				i += de_reclen;
+			}
+			offset = i;
+			filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
+				| offset;
+			filp->f_version = inode->i_version;
+		}
+
+		while (!error && filp->f_pos < inode->i_size
+		       && offset < sb->s_blocksize) {
+			de = (struct ufs_dir_entry *) (bh->b_data + offset);
+			/* XXX - put in a real ufs_check_dir_entry() */
+			if ((de->d_reclen == 0) || (ufs_get_de_namlen(sb, de) == 0)) {
+				filp->f_pos = (filp->f_pos &
+				              (sb->s_blocksize - 1)) +
+				               sb->s_blocksize;
+				brelse(bh);
+				unlock_kernel();
+				return stored;
+			}
+			if (!ufs_check_dir_entry ("ufs_readdir", inode, de,
+						   bh, offset)) {
+				/* On error, skip the f_pos to the
+				   next block. */
+				filp->f_pos = (filp->f_pos |
+				              (sb->s_blocksize - 1)) +
+					       1;
+				brelse (bh);
+				unlock_kernel();
+				return stored;
+			}
+			offset += fs16_to_cpu(sb, de->d_reclen);
+			if (de->d_ino) {
+				/* We might block in the next section
+				 * if the data destination is
+				 * currently swapped out.  So, use a
+				 * version stamp to detect whether or
+				 * not the directory has been modified
+				 * during the copy operation. */
+				unsigned long version = filp->f_version;
+				unsigned char d_type = DT_UNKNOWN;
+
+				UFSD(("filldir(%s,%u)\n", de->d_name,
+							fs32_to_cpu(sb, de->d_ino)))
+				UFSD(("namlen %u\n", ufs_get_de_namlen(sb, de)))
+
+				if ((flags & UFS_DE_MASK) == UFS_DE_44BSD)
+					d_type = de->d_u.d_44.d_type;
+				error = filldir(dirent, de->d_name,
+						ufs_get_de_namlen(sb, de), filp->f_pos,
+						fs32_to_cpu(sb, de->d_ino), d_type);
+				if (error)
+					break;
+				if (version != filp->f_version)
+					goto revalidate;
+				stored ++;
+			}
+			filp->f_pos += fs16_to_cpu(sb, de->d_reclen);
+		}
+		offset = 0;
+		brelse (bh);
+	}
+	unlock_kernel();
+	return 0;
+}
+
+/*
+ * 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))
+
+/*
+ *	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_bh). It does NOT read the inode of the
+ * entry - you'll have to do that yourself if you want to.
+ */
+struct ufs_dir_entry * ufs_find_entry (struct dentry *dentry,
+	struct buffer_head ** res_bh)
+{
+	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;
+	struct inode *dir = dentry->d_parent->d_inode;
+	const char *name = dentry->d_name.name;
+	int namelen = dentry->d_name.len;
+
+	UFSD(("ENTER, dir_ino %lu, name %s, namlen %u\n", dir->i_ino, name, namelen))
+	
+	*res_bh = NULL;
+	
+	sb = dir->i_sb;
+	
+	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) {
+			/* this code is executed quadratically often */
+			/* do minimal checking by hand */
+			int de_len;
+
+			if ((char *) de + namelen <= dlimit &&
+			    ufs_match(sb, namelen, name, de)) {
+				/* found a match -
+				just to be sure, do a full check */
+				if (!ufs_check_dir_entry("ufs_find_entry",
+				    dir, de, bh, offset))
+					goto failed;
+				for (i = 0; i < NAMEI_RA_SIZE; ++i) {
+					if (bh_use[i] != bh)
+						brelse (bh_use[i]);
+				}
+				*res_bh = bh;
+				return de;
+			}
+                        /* prevent looping on a bad block */
+			de_len = fs16_to_cpu(sb, de->d_reclen);
+			if (de_len <= 0)
+				goto failed;
+			offset += de_len;
+			de = (struct ufs_dir_entry *) ((char *) de + de_len);
+		}
+
+		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\n"))
+	return NULL;
+}
+
+static int
+ufs_check_dir_entry (const char *function, struct inode *dir,
+		     struct ufs_dir_entry *de, struct buffer_head *bh,
+		     unsigned long offset)
+{
+	struct super_block *sb = dir->i_sb;
+	const char *error_msg = NULL;
+	int rlen = fs16_to_cpu(sb, de->d_reclen);
+
+	if (rlen < UFS_DIR_REC_LEN(1))
+		error_msg = "reclen is smaller than minimal";
+	else if (rlen % 4 != 0)
+		error_msg = "reclen % 4 != 0";
+	else if (rlen < UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)))
+		error_msg = "reclen is too small for namlen";
+	else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize)
+		error_msg = "directory entry across blocks";
+	else if (fs32_to_cpu(sb, de->d_ino) > (UFS_SB(sb)->s_uspi->s_ipg *
+				      UFS_SB(sb)->s_uspi->s_ncg))
+		error_msg = "inode out of bounds";
+
+	if (error_msg != NULL)
+		ufs_error (sb, function, "bad entry in directory #%lu, size %Lu: %s - "
+			    "offset=%lu, inode=%lu, reclen=%d, namlen=%d",
+			    dir->i_ino, dir->i_size, error_msg, offset,
+			    (unsigned long)fs32_to_cpu(sb, de->d_ino),
+			    rlen, ufs_get_de_namlen(sb, de));
+	
+	return (error_msg == NULL ? 1 : 0);
+}
+
+struct ufs_dir_entry *ufs_dotdot(struct inode *dir, struct buffer_head **p)
+{
+	int err;
+	struct buffer_head *bh = ufs_bread (dir, 0, 0, &err);
+	struct ufs_dir_entry *res = NULL;
+
+	if (bh) {
+		res = (struct ufs_dir_entry *) bh->b_data;
+		res = (struct ufs_dir_entry *)((char *)res +
+			fs16_to_cpu(dir->i_sb, res->d_reclen));
+	}
+	*p = bh;
+	return res;
+}
+ino_t ufs_inode_by_name(struct inode * dir, struct dentry *dentry)
+{
+	ino_t res = 0;
+	struct ufs_dir_entry * de;
+	struct buffer_head *bh;
+
+	de = ufs_find_entry (dentry, &bh);
+	if (de) {
+		res = fs32_to_cpu(dir->i_sb, de->d_ino);
+		brelse(bh);
+	}
+	return res;
+}
+
+void ufs_set_link(struct inode *dir, struct ufs_dir_entry *de,
+		struct buffer_head *bh, struct inode *inode)
+{
+	dir->i_version++;
+	de->d_ino = cpu_to_fs32(dir->i_sb, inode->i_ino);
+	mark_buffer_dirty(bh);
+	if (IS_DIRSYNC(dir))
+		sync_dirty_buffer(bh);
+	brelse (bh);
+}
+
+/*
+ *	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.
+ */
+int ufs_add_link(struct dentry *dentry, struct inode *inode)
+{
+	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;
+	struct inode *dir = dentry->d_parent->d_inode;
+	const char *name = dentry->d_name.name;
+	int namelen = dentry->d_name.len;
+	int err;
+
+	UFSD(("ENTER, name %s, namelen %u\n", name, namelen))
+	
+	sb = dir->i_sb;
+	uspi = UFS_SB(sb)->s_uspi;
+
+	if (!namelen)
+		return -EINVAL;
+	bh = ufs_bread (dir, 0, 0, &err);
+	if (!bh)
+		return err;
+	rec_len = UFS_DIR_REC_LEN(namelen);
+	offset = 0;
+	de = (struct ufs_dir_entry *) bh->b_data;
+	while (1) {
+		if ((char *)de >= UFS_SECTOR_SIZE + bh->b_data) {
+			fragoff = offset & ~uspi->s_fmask;
+			if (fragoff != 0 && fragoff != UFS_SECTOR_SIZE)
+				ufs_error (sb, "ufs_add_entry", "internal error"
+					" fragoff %u", fragoff);
+			if (!fragoff) {
+				brelse (bh);
+				bh = ufs_bread (dir, offset >> sb->s_blocksize_bits, 1, &err);
+				if (!bh)
+					return err;
+			}
+			if (dir->i_size <= offset) {
+				if (dir->i_size == 0) {
+					brelse(bh);
+					return -ENOENT;
+				}
+				de = (struct ufs_dir_entry *) (bh->b_data + fragoff);
+				de->d_ino = 0;
+				de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE);
+				ufs_set_de_namlen(sb, de, 0);
+				dir->i_size = offset + UFS_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)) {
+			brelse (bh);
+			return -ENOENT;
+		}
+		if (ufs_match(sb, namelen, name, de)) {
+			brelse (bh);
+			return -EEXIST;
+		}
+		if (de->d_ino == 0 && fs16_to_cpu(sb, de->d_reclen) >= rec_len)
+			break;
+			
+		if (fs16_to_cpu(sb, de->d_reclen) >=
+		     UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)) + rec_len)
+			break;
+		offset += fs16_to_cpu(sb, de->d_reclen);
+		de = (struct ufs_dir_entry *) ((char *) de + fs16_to_cpu(sb, de->d_reclen));
+	}
+
+	if (de->d_ino) {
+		de1 = (struct ufs_dir_entry *) ((char *) de +
+			UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
+		de1->d_reclen =
+			cpu_to_fs16(sb, fs16_to_cpu(sb, de->d_reclen) -
+				UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
+		de->d_reclen =
+			cpu_to_fs16(sb, UFS_DIR_REC_LEN(ufs_get_de_namlen(sb, de)));
+		de = de1;
+	}
+	de->d_ino = 0;
+	ufs_set_de_namlen(sb, de, namelen);
+	memcpy (de->d_name, name, namelen + 1);
+	de->d_ino = cpu_to_fs32(sb, inode->i_ino);
+	ufs_set_de_type(sb, de, inode->i_mode);
+	mark_buffer_dirty(bh);
+	if (IS_DIRSYNC(dir))
+		sync_dirty_buffer(bh);
+	brelse (bh);
+	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
+	dir->i_version++;
+	mark_inode_dirty(dir);
+
+	UFSD(("EXIT\n"))
+	return 0;
+}
+
+/*
+ * ufs_delete_entry deletes a directory entry by merging it with the
+ * previous entry.
+ */
+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;
+	
+	UFSD(("ENTER\n"))
+
+	sb = inode->i_sb;
+	i = 0;
+	pde = NULL;
+	de = (struct ufs_dir_entry *) bh->b_data;
+	
+	UFSD(("ino %u, reclen %u, namlen %u, name %s\n",
+		fs32_to_cpu(sb, de->d_ino),
+		fs16to_cpu(sb, de->d_reclen),
+		ufs_get_de_namlen(sb, de), de->d_name))
+
+	while (i < bh->b_size) {
+		if (!ufs_check_dir_entry ("ufs_delete_entry", inode, de, bh, i)) {
+			brelse(bh);
+			return -EIO;
+		}
+		if (de == dir)  {
+			if (pde)
+				fs16_add(sb, &pde->d_reclen,
+					fs16_to_cpu(sb, dir->d_reclen));
+			dir->d_ino = 0;
+			inode->i_version++;
+			inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
+			mark_inode_dirty(inode);
+			mark_buffer_dirty(bh);
+			if (IS_DIRSYNC(inode))
+				sync_dirty_buffer(bh);
+			brelse(bh);
+			UFSD(("EXIT\n"))
+			return 0;
+		}
+		i += fs16_to_cpu(sb, de->d_reclen);
+		if (i == UFS_SECTOR_SIZE) pde = NULL;
+		else pde = de;
+		de = (struct ufs_dir_entry *)
+		    ((char *) de + fs16_to_cpu(sb, de->d_reclen));
+		if (i == UFS_SECTOR_SIZE && de->d_reclen == 0)
+			break;
+	}
+	UFSD(("EXIT\n"))
+	brelse(bh);
+	return -ENOENT;
+}
+
+int ufs_make_empty(struct inode * inode, struct inode *dir)
+{
+	struct super_block * sb = dir->i_sb;
+	struct buffer_head * dir_block;
+	struct ufs_dir_entry * de;
+	int err;
+
+	dir_block = ufs_bread (inode, 0, 1, &err);
+	if (!dir_block)
+		return err;
+
+	inode->i_blocks = sb->s_blocksize / UFS_SECTOR_SIZE;
+	de = (struct ufs_dir_entry *) dir_block->b_data;
+	de->d_ino = cpu_to_fs32(sb, inode->i_ino);
+	ufs_set_de_type(sb, de, inode->i_mode);
+	ufs_set_de_namlen(sb, de, 1);
+	de->d_reclen = cpu_to_fs16(sb, UFS_DIR_REC_LEN(1));
+	strcpy (de->d_name, ".");
+	de = (struct ufs_dir_entry *)
+		((char *)de + fs16_to_cpu(sb, de->d_reclen));
+	de->d_ino = cpu_to_fs32(sb, dir->i_ino);
+	ufs_set_de_type(sb, de, dir->i_mode);
+	de->d_reclen = cpu_to_fs16(sb, UFS_SECTOR_SIZE - UFS_DIR_REC_LEN(1));
+	ufs_set_de_namlen(sb, de, 2);
+	strcpy (de->d_name, "..");
+	mark_buffer_dirty(dir_block);
+	brelse (dir_block);
+	mark_inode_dirty(inode);
+	return 0;
+}
+
+/*
+ * routine to check that the specified directory is empty (for rmdir)
+ */
+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;
+	
+	sb = inode->i_sb;
+
+	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 + fs16_to_cpu(sb, de->d_reclen));
+	if (fs32_to_cpu(sb, de->d_ino) != inode->i_ino || de1->d_ino == 0 ||
+	     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 = fs16_to_cpu(sb, de->d_reclen) + fs16_to_cpu(sb, de1->d_reclen);
+	de = (struct ufs_dir_entry *)
+		((char *)de1 + fs16_to_cpu(sb, 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 (de->d_ino) {
+			brelse (bh);
+			return 0;
+		}
+		offset += fs16_to_cpu(sb, de->d_reclen);
+		de = (struct ufs_dir_entry *)
+			((char *)de + fs16_to_cpu(sb, de->d_reclen));
+	}
+	brelse (bh);
+	return 1;
+}
+
+struct file_operations ufs_dir_operations = {
+	.read		= generic_read_dir,
+	.readdir	= ufs_readdir,
+	.fsync		= file_fsync,
+};