C++ dtSearch函数代码示例

static struct dentry *jfs_lookup(struct inode *dip, struct dentry *dentry, struct nameidata *nd)
{
	struct btstack btstack;
	ino_t inum;
	struct inode *ip;
	struct component_name key;
	const char *name = dentry->d_name.name;
	int len = dentry->d_name.len;
	int rc;

	jfs_info("jfs_lookup: name = %s", name);


	if ((name[0] == '.') && (len == 1))
		inum = dip->i_ino;
	else if (strcmp(name, "..") == 0)
		inum = PARENT(dip);
	else {
		if ((rc = get_UCSname(&key, dentry)))
			return ERR_PTR(rc);
		rc = dtSearch(dip, &key, &inum, &btstack, JFS_LOOKUP);
		free_UCSname(&key);
		if (rc == -ENOENT) {
			d_add(dentry, NULL);
			return ERR_PTR(0);
		} else if (rc) {
			jfs_err("jfs_lookup: dtSearch returned %d", rc);
			return ERR_PTR(rc);
		}
	}

	ip = iget(dip->i_sb, inum);
	if (ip == NULL || is_bad_inode(ip)) {
		jfs_err("jfs_lookup: iget failed on inum %d", (uint) inum);
		if (ip)
			iput(ip);
		return ERR_PTR(-EACCES);
	}

	if (JFS_SBI(dip->i_sb)->mntflag & JFS_OS2)
		dentry->d_op = &jfs_ci_dentry_operations;

	dentry = d_splice_alias(ip, dentry);

	if (dentry && (JFS_SBI(dip->i_sb)->mntflag & JFS_OS2))
		dentry->d_op = &jfs_ci_dentry_operations;

	return dentry;
}

static struct dentry *jfs_lookup(struct inode *dip, struct dentry *dentry, struct nameidata *nd)
{
    struct btstack btstack;
    ino_t inum;
    struct inode *ip;
    struct component_name key;
    const char *name = dentry->d_name.name;
    int len = dentry->d_name.len;
    int rc;

    jfs_info("jfs_lookup: name = %s", name);

    if ((name[0] == '.') && (len == 1))
        inum = dip->i_ino;
    else if (strcmp(name, "..") == 0)
        inum = PARENT(dip);
    else {
        if ((rc = get_UCSname(&key, dentry)))
            return ERR_PTR(rc);
        rc = dtSearch(dip, &key, &inum, &btstack, JFS_LOOKUP);
        free_UCSname(&key);
        if (rc == -ENOENT) {
            d_add(dentry, NULL);
            return NULL;
        } else if (rc) {
            jfs_err("jfs_lookup: dtSearch returned %d", rc);
            return ERR_PTR(rc);
        }
    }

    ip = jfs_iget(dip->i_sb, inum);
    if (IS_ERR(ip)) {
        jfs_err("jfs_lookup: iget failed on inum %d", (uint) inum);
        return ERR_CAST(ip);
    }

    return d_splice_alias(ip, dentry);
}

/*
 * NAME:	jfs_mknod
 *
 * FUNCTION:	Create a special file (device)
 */
static int jfs_mknod(struct inode *dir, struct dentry *dentry,
                     int mode, dev_t rdev)
{
    struct jfs_inode_info *jfs_ip;
    struct btstack btstack;
    struct component_name dname;
    ino_t ino;
    struct inode *ip;
    struct inode *iplist[2];
    int rc;
    tid_t tid;
    struct tblock *tblk;

    if (!new_valid_dev(rdev))
        return -EINVAL;

    jfs_info("jfs_mknod: %s", dentry->d_name.name);

    dquot_initialize(dir);

    if ((rc = get_UCSname(&dname, dentry)))
        goto out;

    ip = ialloc(dir, mode);
    if (IS_ERR(ip)) {
        rc = PTR_ERR(ip);
        goto out1;
    }
    jfs_ip = JFS_IP(ip);

    tid = txBegin(dir->i_sb, 0);

    mutex_lock_nested(&JFS_IP(dir)->commit_mutex, COMMIT_MUTEX_PARENT);
    mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);

    rc = jfs_init_acl(tid, ip, dir);
    if (rc)
        goto out3;

    rc = jfs_init_security(tid, ip, dir, &dentry->d_name);
    if (rc) {
        txAbort(tid, 0);
        goto out3;
    }

    if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE))) {
        txAbort(tid, 0);
        goto out3;
    }

    tblk = tid_to_tblock(tid);
    tblk->xflag |= COMMIT_CREATE;
    tblk->ino = ip->i_ino;
    tblk->u.ixpxd = JFS_IP(ip)->ixpxd;

    ino = ip->i_ino;
    if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack))) {
        txAbort(tid, 0);
        goto out3;
    }

    ip->i_op = &jfs_file_inode_operations;
    jfs_ip->dev = new_encode_dev(rdev);
    init_special_inode(ip, ip->i_mode, rdev);

    mark_inode_dirty(ip);

    dir->i_ctime = dir->i_mtime = CURRENT_TIME;

    mark_inode_dirty(dir);

    iplist[0] = dir;
    iplist[1] = ip;
    rc = txCommit(tid, 2, iplist, 0);

out3:
    txEnd(tid);
    mutex_unlock(&JFS_IP(ip)->commit_mutex);
    mutex_unlock(&JFS_IP(dir)->commit_mutex);
    if (rc) {
        free_ea_wmap(ip);
        ip->i_nlink = 0;
        unlock_new_inode(ip);
        iput(ip);
    } else {
        d_instantiate(dentry, ip);
        unlock_new_inode(ip);
    }

out1:
    free_UCSname(&dname);

out:
    jfs_info("jfs_mknod: returning %d", rc);
    return rc;
//.........这里部分代码省略.........

int jfs_symlink(struct inode *dip, struct dentry *dentry, const char *name)
{
	int rc;
	tid_t tid;
	ino_t ino = 0;
	struct component_name dname;
	int ssize;		/* source pathname size */
	struct btstack btstack;
	struct inode *ip = dentry->d_inode;
	unchar *i_fastsymlink;
	s64 xlen = 0;
	int bmask = 0, xsize;
	s64 xaddr;
	struct metapage *mp;
	struct super_block *sb;
	struct tblock *tblk;

	struct inode *iplist[2];

	jFYI(1, ("jfs_symlink: dip:0x%p name:%s\n", dip, name));

	ssize = strlen(name) + 1;

	/*
	 * search parent directory for entry/freespace
	 * (dtSearch() returns parent directory page pinned)
	 */

	if ((rc = get_UCSname(&dname, dentry, JFS_SBI(dip->i_sb)->nls_tab)))
		goto out1;

	/*
	 * allocate on-disk/in-memory inode for symbolic link:
	 * (iAlloc() returns new, locked inode)
	 */
	ip = ialloc(dip, S_IFLNK | 0777);
	if (ip == NULL) {
		rc = ENOSPC;
		goto out2;
	}

	tid = txBegin(dip->i_sb, 0);

	down(&JFS_IP(dip)->commit_sem);
	down(&JFS_IP(ip)->commit_sem);

	if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE)))
		goto out3;

	tblk = tid_to_tblock(tid);
	tblk->xflag |= COMMIT_CREATE;
	tblk->ip = ip;

	/*
	 * create entry for symbolic link in parent directory
	 */

	ino = ip->i_ino;



	if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
		jERROR(1, ("jfs_symlink: dtInsert returned %d\n", rc));
		/* discard ne inode */
		goto out3;

	}

	/* fix symlink access permission
	 * (dir_create() ANDs in the u.u_cmask, 
	 * but symlinks really need to be 777 access)
	 */
	ip->i_mode |= 0777;

	/*
	   *       write symbolic link target path name
	 */
	xtInitRoot(tid, ip);

	/*
	 * write source path name inline in on-disk inode (fast symbolic link)
	 */

	if (ssize <= IDATASIZE) {
		ip->i_op = &jfs_symlink_inode_operations;

		i_fastsymlink = JFS_IP(ip)->i_inline;
		memcpy(i_fastsymlink, name, ssize);
		ip->i_size = ssize - 1;

		/*
		 * if symlink is > 128 bytes, we don't have the space to
		 * store inline extended attributes
		 */
		if (ssize > sizeof (JFS_IP(ip)->i_inline))
			JFS_IP(ip)->mode2 &= ~INLINEEA;

		jFYI(1,
		     ("jfs_symlink: fast symlink added  ssize:%d name:%s \n",
		      ssize, name));
//.........这里部分代码省略.........

/*
 * NAME:	jfs_rename
 *
 * FUNCTION:	rename a file or directory
 */
static int jfs_rename(struct inode *old_dir, struct dentry *old_dentry,
                      struct inode *new_dir, struct dentry *new_dentry)
{
    struct btstack btstack;
    ino_t ino;
    struct component_name new_dname;
    struct inode *new_ip;
    struct component_name old_dname;
    struct inode *old_ip;
    int rc;
    tid_t tid;
    struct tlock *tlck;
    struct dt_lock *dtlck;
    struct lv *lv;
    int ipcount;
    struct inode *iplist[4];
    struct tblock *tblk;
    s64 new_size = 0;
    int commit_flag;


    jfs_info("jfs_rename: %s %s", old_dentry->d_name.name,
             new_dentry->d_name.name);

    dquot_initialize(old_dir);
    dquot_initialize(new_dir);

    old_ip = old_dentry->d_inode;
    new_ip = new_dentry->d_inode;

    if ((rc = get_UCSname(&old_dname, old_dentry)))
        goto out1;

    if ((rc = get_UCSname(&new_dname, new_dentry)))
        goto out2;

    /*
     * Make sure source inode number is what we think it is
     */
    rc = dtSearch(old_dir, &old_dname, &ino, &btstack, JFS_LOOKUP);
    if (rc || (ino != old_ip->i_ino)) {
        rc = -ENOENT;
        goto out3;
    }

    /*
     * Make sure dest inode number (if any) is what we think it is
     */
    rc = dtSearch(new_dir, &new_dname, &ino, &btstack, JFS_LOOKUP);
    if (!rc) {
        if ((!new_ip) || (ino != new_ip->i_ino)) {
            rc = -ESTALE;
            goto out3;
        }
    } else if (rc != -ENOENT)
        goto out3;
    else if (new_ip) {
        /* no entry exists, but one was expected */
        rc = -ESTALE;
        goto out3;
    }

    if (S_ISDIR(old_ip->i_mode)) {
        if (new_ip) {
            if (!dtEmpty(new_ip)) {
                rc = -ENOTEMPTY;
                goto out3;
            }
        } else if ((new_dir != old_dir) &&
                   (new_dir->i_nlink == JFS_LINK_MAX)) {
            rc = -EMLINK;
            goto out3;
        }
    } else if (new_ip) {
        IWRITE_LOCK(new_ip, RDWRLOCK_NORMAL);
        /* Init inode for quota operations. */
        dquot_initialize(new_ip);
    }

    /*
     * The real work starts here
     */
    tid = txBegin(new_dir->i_sb, 0);

    /*
     * How do we know the locking is safe from deadlocks?
     * The vfs does the hard part for us.  Any time we are taking nested
     * commit_mutexes, the vfs already has i_mutex held on the parent.
     * Here, the vfs has already taken i_mutex on both old_dir and new_dir.
     */
    mutex_lock_nested(&JFS_IP(new_dir)->commit_mutex, COMMIT_MUTEX_PARENT);
    mutex_lock_nested(&JFS_IP(old_ip)->commit_mutex, COMMIT_MUTEX_CHILD);
    if (old_dir != new_dir)
        mutex_lock_nested(&JFS_IP(old_dir)->commit_mutex,
                          COMMIT_MUTEX_SECOND_PARENT);
//.........这里部分代码省略.........

//.........这里部分代码省略.........
        if (ssize > sizeof (JFS_IP(ip)->i_inline))
            JFS_IP(ip)->mode2 &= ~INLINEEA;

        jfs_info("jfs_symlink: fast symlink added  ssize:%d name:%s ",
                 ssize, name);
    }
    /*
     * write source path name in a single extent
     */
    else {
        jfs_info("jfs_symlink: allocate extent ip:0x%p", ip);

        ip->i_op = &jfs_symlink_inode_operations;
        ip->i_mapping->a_ops = &jfs_aops;

        /*
         * even though the data of symlink object (source
         * path name) is treated as non-journaled user data,
         * it is read/written thru buffer cache for performance.
         */
        sb = ip->i_sb;
        bmask = JFS_SBI(sb)->bsize - 1;
        xsize = (ssize + bmask) & ~bmask;
        xaddr = 0;
        xlen = xsize >> JFS_SBI(sb)->l2bsize;
        if ((rc = xtInsert(tid, ip, 0, 0, xlen, &xaddr, 0))) {
            txAbort(tid, 0);
            goto out3;
        }
        extent = xaddr;
        ip->i_size = ssize - 1;
        while (ssize) {
            /* This is kind of silly since PATH_MAX == 4K */
            int copy_size = min(ssize, PSIZE);

            mp = get_metapage(ip, xaddr, PSIZE, 1);

            if (mp == NULL) {
                xtTruncate(tid, ip, 0, COMMIT_PWMAP);
                rc = -EIO;
                txAbort(tid, 0);
                goto out3;
            }
            memcpy(mp->data, name, copy_size);
            flush_metapage(mp);
            ssize -= copy_size;
            name += copy_size;
            xaddr += JFS_SBI(sb)->nbperpage;
        }
    }

    /*
     * create entry for symbolic link in parent directory
     */
    rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE);
    if (rc == 0) {
        ino = ip->i_ino;
        rc = dtInsert(tid, dip, &dname, &ino, &btstack);
    }
    if (rc) {
        if (xlen)
            xtTruncate(tid, ip, 0, COMMIT_PWMAP);
        txAbort(tid, 0);
        /* discard new inode */
        goto out3;
    }

    mark_inode_dirty(ip);

    dip->i_ctime = dip->i_mtime = CURRENT_TIME;
    mark_inode_dirty(dip);
    /*
     * commit update of parent directory and link object
     */

    iplist[0] = dip;
    iplist[1] = ip;
    rc = txCommit(tid, 2, &iplist[0], 0);

out3:
    txEnd(tid);
    mutex_unlock(&JFS_IP(ip)->commit_mutex);
    mutex_unlock(&JFS_IP(dip)->commit_mutex);
    if (rc) {
        free_ea_wmap(ip);
        ip->i_nlink = 0;
        unlock_new_inode(ip);
        iput(ip);
    } else {
        d_instantiate(dentry, ip);
        unlock_new_inode(ip);
    }

out2:
    free_UCSname(&dname);

out1:
    jfs_info("jfs_symlink: rc:%d", rc);
    return rc;
}

/*
 * NAME:        jfs_mknod
 *
 * FUNCTION:    Create a special file (device)
 */
static int jfs_mknod(struct inode *dir, struct dentry *dentry,
		int mode, dev_t rdev)
{
	struct jfs_inode_info *jfs_ip;
	struct btstack btstack;
	struct component_name dname;
	ino_t ino;
	struct inode *ip;
	struct inode *iplist[2];
	int rc;
	tid_t tid;
	struct tblock *tblk;

	if (!new_valid_dev(rdev))
		return -EINVAL;

	jfs_info("jfs_mknod: %s", dentry->d_name.name);

	if ((rc = get_UCSname(&dname, dentry)))
		goto out;

	ip = ialloc(dir, mode);
	if (ip == NULL) {
		rc = -ENOSPC;
		goto out1;
	}
	jfs_ip = JFS_IP(ip);

	tid = txBegin(dir->i_sb, 0);

	down(&JFS_IP(dir)->commit_sem);
	down(&JFS_IP(ip)->commit_sem);

	if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE)))
		goto out3;

	tblk = tid_to_tblock(tid);
	tblk->xflag |= COMMIT_CREATE;
	tblk->ino = ip->i_ino;
	tblk->u.ixpxd = JFS_IP(ip)->ixpxd;

	ino = ip->i_ino;
	if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack)))
		goto out3;

	ip->i_op = &jfs_file_inode_operations;
	jfs_ip->dev = new_encode_dev(rdev);
	init_special_inode(ip, ip->i_mode, rdev);

	insert_inode_hash(ip);
	mark_inode_dirty(ip);

	dir->i_ctime = dir->i_mtime = CURRENT_TIME;

	mark_inode_dirty(dir);

	iplist[0] = dir;
	iplist[1] = ip;
	rc = txCommit(tid, 2, iplist, 0);

      out3:
	txEnd(tid);
	up(&JFS_IP(ip)->commit_sem);
	up(&JFS_IP(dir)->commit_sem);
	if (rc) {
		ip->i_nlink = 0;
		iput(ip);
	} else
		d_instantiate(dentry, ip);

      out1:
	free_UCSname(&dname);

#ifdef CONFIG_JFS_POSIX_ACL
	if (rc == 0)
		jfs_init_acl(ip, dir);
#endif

      out:
	jfs_info("jfs_mknod: returning %d", rc);
	return rc;
}

/*
 * NAME:	jfs_create(dip, dentry, mode)
 *
 * FUNCTION:	create a regular file in the parent directory <dip>
 *		with name = <from dentry> and mode = <mode>
 *
 * PARAMETER:	dip	- parent directory vnode
 *		dentry	- dentry of new file
 *		mode	- create mode (rwxrwxrwx).
 *		nd- nd struct
 *
 * RETURN:	Errors from subroutines
 *
 */
static int jfs_create(struct inode *dip, struct dentry *dentry, int mode,
                      struct nameidata *nd)
{
    int rc = 0;
    tid_t tid;		/* transaction id */
    struct inode *ip = NULL;	/* child directory inode */
    ino_t ino;
    struct component_name dname;	/* child directory name */
    struct btstack btstack;
    struct inode *iplist[2];
    struct tblock *tblk;

    jfs_info("jfs_create: dip:0x%p name:%s", dip, dentry->d_name.name);

    dquot_initialize(dip);

    /*
     * search parent directory for entry/freespace
     * (dtSearch() returns parent directory page pinned)
     */
    if ((rc = get_UCSname(&dname, dentry)))
        goto out1;

    /*
     * Either iAlloc() or txBegin() may block.  Deadlock can occur if we
     * block there while holding dtree page, so we allocate the inode &
     * begin the transaction before we search the directory.
     */
    ip = ialloc(dip, mode);
    if (IS_ERR(ip)) {
        rc = PTR_ERR(ip);
        goto out2;
    }

    tid = txBegin(dip->i_sb, 0);

    mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
    mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);

    rc = jfs_init_acl(tid, ip, dip);
    if (rc)
        goto out3;

    rc = jfs_init_security(tid, ip, dip, &dentry->d_name);
    if (rc) {
        txAbort(tid, 0);
        goto out3;
    }

    if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE))) {
        jfs_err("jfs_create: dtSearch returned %d", rc);
        txAbort(tid, 0);
        goto out3;
    }

    tblk = tid_to_tblock(tid);
    tblk->xflag |= COMMIT_CREATE;
    tblk->ino = ip->i_ino;
    tblk->u.ixpxd = JFS_IP(ip)->ixpxd;

    iplist[0] = dip;
    iplist[1] = ip;

    /*
     * initialize the child XAD tree root in-line in inode
     */
    xtInitRoot(tid, ip);

    /*
     * create entry in parent directory for child directory
     * (dtInsert() releases parent directory page)
     */
    ino = ip->i_ino;
    if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
        if (rc == -EIO) {
            jfs_err("jfs_create: dtInsert returned -EIO");
            txAbort(tid, 1);	/* Marks Filesystem dirty */
        } else
            txAbort(tid, 0);	/* Filesystem full */
        goto out3;
    }

    ip->i_op = &jfs_file_inode_operations;
    ip->i_fop = &jfs_file_operations;
    ip->i_mapping->a_ops = &jfs_aops;

//.........这里部分代码省略.........

/*
 * NAME:	jfs_link(vp, dvp, name, crp)
 *
 * FUNCTION:	create a link to <vp> by the name = <name>
 *		in the parent directory <dvp>
 *
 * PARAMETER:	vp 	- target object
 *		dvp	- parent directory of new link
 *		name	- name of new link to target object
 *		crp	- credential
 *
 * RETURN:	Errors from subroutines
 *
 * note:
 * JFS does NOT support link() on directories (to prevent circular
 * path in the directory hierarchy);
 * EPERM: the target object is a directory, and either the caller
 * does not have appropriate privileges or the implementation prohibits
 * using link() on directories [XPG4.2].
 *
 * JFS does NOT support links between file systems:
 * EXDEV: target object and new link are on different file systems and
 * implementation does not support links between file systems [XPG4.2].
 */
int jfs_link(struct dentry *old_dentry,
	     struct inode *dir, struct dentry *dentry)
{
	int rc;
	tid_t tid;
	struct inode *ip = old_dentry->d_inode;
	ino_t ino;
	struct component_name dname;
	struct btstack btstack;
	struct inode *iplist[2];

	jFYI(1,
	     ("jfs_link: %s %s\n", old_dentry->d_name.name,
	      dentry->d_name.name));

	/* JFS does NOT support link() on directories */
	if (S_ISDIR(ip->i_mode))
		return -EPERM;

	tid = txBegin(ip->i_sb, 0);

	down(&JFS_IP(dir)->commit_sem);
	down(&JFS_IP(ip)->commit_sem);

	if (ip->i_nlink == JFS_LINK_MAX) {
		rc = EMLINK;
		goto out;
	}

	/*
	 * scan parent directory for entry/freespace
	 */
	if ((rc = get_UCSname(&dname, dentry, JFS_SBI(ip->i_sb)->nls_tab)))
		goto out;

	if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE)))
		goto out;

	/*
	 * create entry for new link in parent directory
	 */
	ino = ip->i_ino;
	if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack)))
		goto out;

	/* update object inode */
	ip->i_nlink++;		/* for new link */
	ip->i_ctime = CURRENT_TIME;
	mark_inode_dirty(dir);
	atomic_inc(&ip->i_count);
	d_instantiate(dentry, ip);

	iplist[0] = ip;
	iplist[1] = dir;
	rc = txCommit(tid, 2, &iplist[0], 0);

      out:
	txEnd(tid);

	up(&JFS_IP(dir)->commit_sem);
	up(&JFS_IP(ip)->commit_sem);

	jFYI(1, ("jfs_link: rc:%d\n", rc));
	return -rc;
}

/*
 * NAME:	jfs_create(dip, dentry, mode)
 *
 * FUNCTION:	create a regular file in the parent directory <dip>
 *		with name = <from dentry> and mode = <mode>
 *
 * PARAMETER:	dip 	- parent directory vnode
 *		dentry	- dentry of new file
 *		mode	- create mode (rwxrwxrwx).
 *
 * RETURN:	Errors from subroutines
 *
 */
int jfs_create(struct inode *dip, struct dentry *dentry, int mode)
{
	int rc = 0;
	tid_t tid;		/* transaction id */
	struct inode *ip = NULL;	/* child directory inode */
	ino_t ino;
	struct component_name dname;	/* child directory name */
	struct btstack btstack;
	struct inode *iplist[2];
	struct tblock *tblk;

	jFYI(1, ("jfs_create: dip:0x%p name:%s\n", dip, dentry->d_name.name));

	/*
	 * search parent directory for entry/freespace
	 * (dtSearch() returns parent directory page pinned)
	 */
	if ((rc = get_UCSname(&dname, dentry, JFS_SBI(dip->i_sb)->nls_tab)))
		goto out1;

	/*
	 * Either iAlloc() or txBegin() may block.  Deadlock can occur if we
	 * block there while holding dtree page, so we allocate the inode &
	 * begin the transaction before we search the directory.
	 */
	ip = ialloc(dip, mode);
	if (ip == NULL) {
		rc = ENOSPC;
		goto out2;
	}

	tid = txBegin(dip->i_sb, 0);

	down(&JFS_IP(dip)->commit_sem);
	down(&JFS_IP(ip)->commit_sem);

	if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE))) {
		jERROR(1, ("jfs_create: dtSearch returned %d\n", rc));
		goto out3;
	}

	tblk = tid_to_tblock(tid);
	tblk->xflag |= COMMIT_CREATE;
	tblk->ip = ip;

	iplist[0] = dip;
	iplist[1] = ip;

	/*
	 * initialize the child XAD tree root in-line in inode
	 */
	xtInitRoot(tid, ip);

	/*
	 * create entry in parent directory for child directory
	 * (dtInsert() releases parent directory page)
	 */
	ino = ip->i_ino;
	if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
		jERROR(1, ("jfs_create: dtInsert returned %d\n", rc));
		if (rc == EIO)
			txAbort(tid, 1);	/* Marks Filesystem dirty */
		else
			txAbort(tid, 0);	/* Filesystem full */
		goto out3;
	}

	ip->i_op = &jfs_file_inode_operations;
	ip->i_fop = &jfs_file_operations;
	ip->i_mapping->a_ops = &jfs_aops;

	insert_inode_hash(ip);
	mark_inode_dirty(ip);
	d_instantiate(dentry, ip);

	dip->i_ctime = dip->i_mtime = CURRENT_TIME;

	mark_inode_dirty(dip);

	rc = txCommit(tid, 2, &iplist[0], 0);

      out3:
	txEnd(tid);
	up(&JFS_IP(dip)->commit_sem);
	up(&JFS_IP(ip)->commit_sem);
	if (rc) {
		ip->i_nlink = 0;
//.........这里部分代码省略.........

/*
 * NAME:        jfs_mknod
 *
 * FUNCTION:    Create a special file (device)
 */
int jfs_mknod(struct inode *dir, struct dentry *dentry, int mode, int rdev)
{
	struct btstack btstack;
	struct component_name dname;
	ino_t ino;
	struct inode *ip;
	struct inode *iplist[2];
	int rc;
	tid_t tid;
	struct tblock *tblk;

	jFYI(1, ("jfs_mknod: %s\n", dentry->d_name.name));

	if ((rc = get_UCSname(&dname, dentry, JFS_SBI(dir->i_sb)->nls_tab)))
		goto out;

	ip = ialloc(dir, mode);
	if (ip == NULL) {
		rc = ENOSPC;
		goto out1;
	}

	tid = txBegin(dir->i_sb, 0);

	down(&JFS_IP(dir)->commit_sem);
	down(&JFS_IP(ip)->commit_sem);

	if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE)))
		goto out3;

	tblk = tid_to_tblock(tid);
	tblk->xflag |= COMMIT_CREATE;
	tblk->ip = ip;

	ino = ip->i_ino;
	if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack)))
		goto out3;

	ip->i_op = &jfs_file_inode_operations;
	init_special_inode(ip, ip->i_mode, rdev);

	insert_inode_hash(ip);
	mark_inode_dirty(ip);
	d_instantiate(dentry, ip);

	dir->i_ctime = dir->i_mtime = CURRENT_TIME;

	mark_inode_dirty(dir);

	iplist[0] = dir;
	iplist[1] = ip;
	rc = txCommit(tid, 2, iplist, 0);

      out3:
	txEnd(tid);
	up(&JFS_IP(ip)->commit_sem);
	up(&JFS_IP(dir)->commit_sem);
	if (rc) {
		ip->i_nlink = 0;
		iput(ip);
	}

      out1:
	free_UCSname(&dname);

      out:
	jFYI(1, ("jfs_mknod: returning %d\n", rc));
	return -rc;
}

/*
 * NAME:        jfs_rename
 *
 * FUNCTION:    rename a file or directory
 */
int jfs_rename(struct inode *old_dir, struct dentry *old_dentry,
	       struct inode *new_dir, struct dentry *new_dentry)
{
	struct btstack btstack;
	ino_t ino;
	struct component_name new_dname;
	struct inode *new_ip;
	struct component_name old_dname;
	struct inode *old_ip;
	int rc;
	tid_t tid;
	struct tlock *tlck;
	struct dt_lock *dtlck;
	struct lv *lv;
	int ipcount;
	struct inode *iplist[4];
	struct tblock *tblk;
	s64 new_size = 0;
	int commit_flag;


	jFYI(1,
	     ("jfs_rename: %s %s\n", old_dentry->d_name.name,
	      new_dentry->d_name.name));

	old_ip = old_dentry->d_inode;
	new_ip = new_dentry->d_inode;

	if ((rc = get_UCSname(&old_dname, old_dentry,
			      JFS_SBI(old_dir->i_sb)->nls_tab)))
		goto out1;

	if ((rc = get_UCSname(&new_dname, new_dentry,
			      JFS_SBI(old_dir->i_sb)->nls_tab)))
		goto out2;

	/*
	 * Make sure source inode number is what we think it is
	 */
	rc = dtSearch(old_dir, &old_dname, &ino, &btstack, JFS_LOOKUP);
	if (rc || (ino != old_ip->i_ino)) {
		rc = ENOENT;
		goto out3;
	}

	/*
	 * Make sure dest inode number (if any) is what we think it is
	 */
	rc = dtSearch(new_dir, &new_dname, &ino, &btstack, JFS_LOOKUP);
	if (rc == 0) {
		if ((new_ip == 0) || (ino != new_ip->i_ino)) {
			rc = ESTALE;
			goto out3;
		}
	} else if (rc != ENOENT)
		goto out3;
	else if (new_ip) {
		/* no entry exists, but one was expected */
		rc = ESTALE;
		goto out3;
	}

	if (S_ISDIR(old_ip->i_mode)) {
		if (new_ip) {
			if (!dtEmpty(new_ip)) {
				rc = ENOTEMPTY;
				goto out3;
			}
		} else if ((new_dir != old_dir) &&
			   (new_dir->i_nlink == JFS_LINK_MAX)) {
			rc = EMLINK;
			goto out3;
		}
	} else if (new_ip)
		IWRITE_LOCK(new_ip);

	/*
	 * The real work starts here
	 */
	tid = txBegin(new_dir->i_sb, 0);

	down(&JFS_IP(new_dir)->commit_sem);
	down(&JFS_IP(old_ip)->commit_sem);
	if (old_dir != new_dir)
		down(&JFS_IP(old_dir)->commit_sem);

	if (new_ip) {
		down(&JFS_IP(new_ip)->commit_sem);
		/*
		 * Change existing directory entry to new inode number
		 */
		ino = new_ip->i_ino;
		rc = dtModify(tid, new_dir, &new_dname, &ino,
			      old_ip->i_ino, JFS_RENAME);
		if (rc)
//.........这里部分代码省略.........

/*
 * NAME:	jfs_link(vp, dvp, name, crp)
 *
 * FUNCTION:	create a link to <vp> by the name = <name>
 *		in the parent directory <dvp>
 *
 * PARAMETER:	vp	- target object
 *		dvp	- parent directory of new link
 *		name	- name of new link to target object
 *		crp	- credential
 *
 * RETURN:	Errors from subroutines
 *
 * note:
 * JFS does NOT support link() on directories (to prevent circular
 * path in the directory hierarchy);
 * EPERM: the target object is a directory, and either the caller
 * does not have appropriate privileges or the implementation prohibits
 * using link() on directories [XPG4.2].
 *
 * JFS does NOT support links between file systems:
 * EXDEV: target object and new link are on different file systems and
 * implementation does not support links between file systems [XPG4.2].
 */
static int jfs_link(struct dentry *old_dentry,
                    struct inode *dir, struct dentry *dentry)
{
    int rc;
    tid_t tid;
    struct inode *ip = old_dentry->d_inode;
    ino_t ino;
    struct component_name dname;
    struct btstack btstack;
    struct inode *iplist[2];

    jfs_info("jfs_link: %s %s", old_dentry->d_name.name,
             dentry->d_name.name);

    if (ip->i_nlink == JFS_LINK_MAX)
        return -EMLINK;

    dquot_initialize(dir);

    tid = txBegin(ip->i_sb, 0);

    mutex_lock_nested(&JFS_IP(dir)->commit_mutex, COMMIT_MUTEX_PARENT);
    mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);

    /*
     * scan parent directory for entry/freespace
     */
    if ((rc = get_UCSname(&dname, dentry)))
        goto out;

    if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE)))
        goto free_dname;

    /*
     * create entry for new link in parent directory
     */
    ino = ip->i_ino;
    if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack)))
        goto free_dname;

    /* update object inode */
    inc_nlink(ip);		/* for new link */
    ip->i_ctime = CURRENT_TIME;
    dir->i_ctime = dir->i_mtime = CURRENT_TIME;
    mark_inode_dirty(dir);
    ihold(ip);

    iplist[0] = ip;
    iplist[1] = dir;
    rc = txCommit(tid, 2, &iplist[0], 0);

    if (rc) {
        ip->i_nlink--; /* never instantiated */
        iput(ip);
    } else
        d_instantiate(dentry, ip);

free_dname:
    free_UCSname(&dname);

out:
    txEnd(tid);

    mutex_unlock(&JFS_IP(ip)->commit_mutex);
    mutex_unlock(&JFS_IP(dir)->commit_mutex);

    jfs_info("jfs_link: rc:%d", rc);
    return rc;
}

/*
 * NAME:	jfs_mkdir(dip, dentry, mode)
 *
 * FUNCTION:	create a child directory in the parent directory <dip>
 *		with name = <from dentry> and mode = <mode>
 *
 * PARAMETER:	dip 	- parent directory vnode
 *		dentry	- dentry of child directory
 *		mode	- create mode (rwxrwxrwx).
 *
 * RETURN:	Errors from subroutines
 *
 * note:
 * EACCESS: user needs search+write permission on the parent directory
 */
static int jfs_mkdir(struct inode *dip, struct dentry *dentry, int mode)
{
	int rc = 0;
	tid_t tid;		/* transaction id */
	struct inode *ip = NULL;	/* child directory inode */
	ino_t ino;
	struct component_name dname;	/* child directory name */
	struct btstack btstack;
	struct inode *iplist[2];
	struct tblock *tblk;

	jfs_info("jfs_mkdir: dip:0x%p name:%s", dip, dentry->d_name.name);

	/* link count overflow on parent directory ? */
	if (dip->i_nlink == JFS_LINK_MAX) {
		rc = -EMLINK;
		goto out1;
	}

	/*
	 * search parent directory for entry/freespace
	 * (dtSearch() returns parent directory page pinned)
	 */
	if ((rc = get_UCSname(&dname, dentry)))
		goto out1;

	/*
	 * Either iAlloc() or txBegin() may block.  Deadlock can occur if we
	 * block there while holding dtree page, so we allocate the inode &
	 * begin the transaction before we search the directory.
	 */
	ip = ialloc(dip, S_IFDIR | mode);
	if (ip == NULL) {
		rc = -ENOSPC;
		goto out2;
	}

	tid = txBegin(dip->i_sb, 0);

	mutex_lock(&JFS_IP(dip)->commit_mutex);
	mutex_lock(&JFS_IP(ip)->commit_mutex);

	rc = jfs_init_acl(tid, ip, dip);
	if (rc)
		goto out3;

	rc = jfs_init_security(tid, ip, dip);
	if (rc) {
		txAbort(tid, 0);
		goto out3;
	}

	if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE))) {
		jfs_err("jfs_mkdir: dtSearch returned %d", rc);
		txAbort(tid, 0);
		goto out3;
	}

	tblk = tid_to_tblock(tid);
	tblk->xflag |= COMMIT_CREATE;
	tblk->ino = ip->i_ino;
	tblk->u.ixpxd = JFS_IP(ip)->ixpxd;

	iplist[0] = dip;
	iplist[1] = ip;

	/*
	 * initialize the child directory in-line in inode
	 */
	dtInitRoot(tid, ip, dip->i_ino);

	/*
	 * create entry in parent directory for child directory
	 * (dtInsert() releases parent directory page)
	 */
	ino = ip->i_ino;
	if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
		if (rc == -EIO) {
			jfs_err("jfs_mkdir: dtInsert returned -EIO");
			txAbort(tid, 1);	/* Marks Filesystem dirty */
		} else
			txAbort(tid, 0);	/* Filesystem full */
		goto out3;
	}

//.........这里部分代码省略.........