namei.c

jfs-2.4-1.1.7.tar.gz jfs 2.4－1.1.7 源码

				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;
		}
		ip->i_blocks = LBLK2PBLK(sb, xlen);
	}

	/*
	 * 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)
			dbFree(ip, extent, xlen);
		txAbort(tid, 0);
		/* discard new inode */
		goto out3;
	}

	insert_inode_hash(ip);
	mark_inode_dirty(ip);

	/*
	 * commit update of parent directory and link object
	 */

	iplist[0] = dip;
	iplist[1] = ip;
	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;
		iput(ip);
	} else
		d_instantiate(dentry, ip);

      out2:
	free_UCSname(&dname);

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


/*
 * 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);

	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)
			goto out4;
		new_ip->i_nlink--;
		if (S_ISDIR(new_ip->i_mode)) {
			new_ip->i_nlink--;
			if (new_ip->i_nlink) {
				up(&JFS_IP(new_dir)->commit_sem);
				up(&JFS_IP(old_ip)->commit_sem);
				if (old_dir != new_dir)
					up(&JFS_IP(old_dir)->commit_sem);
				if (!S_ISDIR(old_ip->i_mode) && new_ip)
					IWRITE_UNLOCK(new_ip);
				jfs_error(new_ip->i_sb,
					  "jfs_rename: new_ip->i_nlink != 0");
				return -EIO;
			}
			tblk = tid_to_tblock(tid);
			tblk->xflag |= COMMIT_DELETE;
			tblk->ip = new_ip;
		} else if (new_ip->i_nlink == 0) {
			assert(!test_cflag(COMMIT_Nolink, new_ip));
			/* free block resources */
			if ((new_size = commitZeroLink(tid, new_ip)) < 0) {
				txAbort(tid, 1);	/* Marks FS Dirty */
				rc = new_size;		
				goto out4;
			}
			tblk = tid_to_tblock(tid);
			tblk->xflag |= COMMIT_DELETE;
			tblk->ip = new_ip;
		} else {
			new_ip->i_ctime = CURRENT_TIME;
			mark_inode_dirty(new_ip);
		}
	} else {
		/*
		 * Add new directory entry
		 */
		rc = dtSearch(new_dir, &new_dname, &ino, &btstack,
			      JFS_CREATE);
		if (rc) {
			jfs_err("jfs_rename didn't expect dtSearch to fail "
				"w/rc = %d", rc);
			goto out4;
		}

		ino = old_ip->i_ino;
		rc = dtInsert(tid, new_dir, &new_dname, &ino, &btstack);
		if (rc) {
			jfs_err("jfs_rename: dtInsert failed w/rc = %d",
				rc);
			goto out4;
		}
		if (S_ISDIR(old_ip->i_mode))
			new_dir->i_nlink++;
	}
	/*
	 * Remove old directory entry
	 */

	ino = old_ip->i_ino;
	rc = dtDelete(tid, old_dir, &old_dname, &ino, JFS_REMOVE);
	if (rc) {
		jfs_err("jfs_rename did not expect dtDelete to return rc = %d",
			rc);
		txAbort(tid, 1);	/* Marks Filesystem dirty */
		goto out4;
	}
	if (S_ISDIR(old_ip->i_mode)) {
		old_dir->i_nlink--;
		if (old_dir != new_dir) {
			/*
			 * Change inode number of parent for moved directory
			 */

			JFS_IP(old_ip)->i_dtroot.header.idotdot =
				cpu_to_le32(new_dir->i_ino);

			/* Linelock header of dtree */
			tlck = txLock(tid, old_ip,
				    (struct metapage *) &JFS_IP(old_ip)->bxflag,
				      tlckDTREE | tlckBTROOT | tlckRELINK);
			dtlck = (struct dt_lock *) & tlck->lock;
			ASSERT(dtlck->index == 0);
			lv = & dtlck->lv[0];
			lv->offset = 0;
			lv->length = 1;
			dtlck->index++;
		}
	}

	/*
	 * Update ctime on changed/moved inodes & mark dirty
	 */
	old_ip->i_ctime = CURRENT_TIME;
	mark_inode_dirty(old_ip);

	new_dir->i_ctime = new_dir->i_mtime = CURRENT_TIME;
	mark_inode_dirty(new_dir);

	/* Build list of inodes modified by this transaction */
	ipcount = 0;
	iplist[ipcount++] = old_ip;
	if (new_ip)
		iplist[ipcount++] = new_ip;
	iplist[ipcount++] = old_dir;

	if (old_dir != new_dir) {
		iplist[ipcount++] = new_dir;
		old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME;
		mark_inode_dirty(old_dir);
	}

	/*
	 * Incomplete truncate of file data can
	 * result in timing problems unless we synchronously commit the
	 * transaction.
	 */
	if (new_size)
		commit_flag = COMMIT_SYNC;
	else
		commit_flag = 0;

	rc = txCommit(tid, ipcount, iplist, commit_flag);

      out4:
	txEnd(tid);

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

	while (new_size && (rc == 0)) {
		tid = txBegin(new_ip->i_sb, 0);
		down(&JFS_IP(new_ip)->commit_sem);
		new_size = xtTruncate_pmap(tid, new_ip, new_size);
		if (new_size < 0) {
			txAbort(tid, 1);
			rc = new_size;		
		} else
			rc = txCommit(tid, 1, &new_ip, COMMIT_SYNC);
		txEnd(tid);
		up(&JFS_IP(new_ip)->commit_sem);
	}
	if (new_ip && (new_ip->i_nlink == 0))
		set_cflag(COMMIT_Nolink, new_ip);
      out3:
	free_UCSname(&new_dname);
      out2:
	free_UCSname(&old_dname);
      out1:
	if (new_ip && !S_ISDIR(new_ip->i_mode))
		IWRITE_UNLOCK(new_ip);
	/*
	 * Truncating the directory index table is not guaranteed.  It
	 * may need to be done iteratively
	 */
	if (test_cflag(COMMIT_Stale, old_dir)) {
		if (old_dir->i_size > 1)
			jfs_truncate_nolock(old_dir, 0);

		clear_cflag(COMMIT_Stale, old_dir);
	}

	jfs_info("jfs_rename: returning %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, 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;

	jfs_info("jfs_mknod: %s", 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_special_inode_operations;
	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);

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

static struct dentry *jfs_lookup(struct inode *dip, struct dentry *dentry)
{
	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, JFS_SBI(dip->i_sb)->nls_tab)))
			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) {
		jfs_err("jfs_lookup: iget failed on inum %d", (uint) inum);
		return ERR_PTR(-EACCES);
	}
	if (is_bad_inode(ip)) {
		jfs_err("jfs_lookup: iget returned bad inode, inum = %d",
			(uint) inum);
		iput(ip);
		return ERR_PTR(-EACCES);
	}

	d_add(dentry, ip);

	return ERR_PTR(0);
}

struct inode_operations jfs_dir_inode_operations = {
	.create		= jfs_create,
	.lookup		= jfs_lookup,
	.link		= jfs_link,
	.unlink		= jfs_unlink,
	.symlink	= jfs_symlink,
	.mkdir		= jfs_mkdir,
	.rmdir		= jfs_rmdir,
	.mknod		= jfs_mknod,
	.rename		= jfs_rename,
#ifdef JFS_XATTR
	.setxattr	= jfs_setxattr,
	.getxattr	= jfs_getxattr,
	.listxattr	= jfs_listxattr,
	.removexattr	= jfs_removexattr,
#endif
};

struct file_operations jfs_dir_operations = {
	.read		= generic_read_dir,
	.readdir	= jfs_readdir,
	.fsync		= jfs_fsync,
};