예제 #1
0
STATIC loff_t
xfs_seek_hole(
	struct file		*file,
	loff_t			start,
	u32			type)
{
	struct inode		*inode = file->f_mapping->host;
	struct xfs_inode	*ip = XFS_I(inode);
	struct xfs_mount	*mp = ip->i_mount;
	loff_t			uninitialized_var(offset);
	loff_t			holeoff;
	xfs_fsize_t		isize;
	xfs_fileoff_t		fsbno;
	uint			lock;
	int			error;

	if (XFS_FORCED_SHUTDOWN(mp))
		return -XFS_ERROR(EIO);

	lock = xfs_ilock_map_shared(ip);

	isize = i_size_read(inode);
	if (start >= isize) {
		error = ENXIO;
		goto out_unlock;
	}

	fsbno = XFS_B_TO_FSBT(mp, start);
	error = xfs_bmap_first_unused(NULL, ip, 1, &fsbno, XFS_DATA_FORK);
	if (error)
		goto out_unlock;

	holeoff = XFS_FSB_TO_B(mp, fsbno);
	if (holeoff <= start)
		offset = start;
	else {
		/*
		 * xfs_bmap_first_unused() could return a value bigger than
		 * isize if there are no more holes past the supplied offset.
		 */
		offset = min_t(loff_t, holeoff, isize);
	}

	if (offset != file->f_pos)
		file->f_pos = offset;

out_unlock:
	xfs_iunlock_map_shared(ip, lock);

	if (error)
		return -error;
	return offset;
}
예제 #2
0
파일: xfs_ioctl.c 프로젝트: AiWinters/linux
/*
 * xfs_find_handle maps from userspace xfs_fsop_handlereq structure to
 * a file or fs handle.
 *
 * XFS_IOC_PATH_TO_FSHANDLE
 *    returns fs handle for a mount point or path within that mount point
 * XFS_IOC_FD_TO_HANDLE
 *    returns full handle for a FD opened in user space
 * XFS_IOC_PATH_TO_HANDLE
 *    returns full handle for a path
 */
int
xfs_find_handle(
	unsigned int		cmd,
	xfs_fsop_handlereq_t	*hreq)
{
	int			hsize;
	xfs_handle_t		handle;
	struct inode		*inode;
	struct fd		f = {0};
	struct path		path;
	int			error;
	struct xfs_inode	*ip;

	if (cmd == XFS_IOC_FD_TO_HANDLE) {
		f = fdget(hreq->fd);
		if (!f.file)
			return -EBADF;
		inode = file_inode(f.file);
	} else {
		error = user_lpath((const char __user *)hreq->path, &path);
		if (error)
			return error;
		inode = path.dentry->d_inode;
	}
	ip = XFS_I(inode);

	/*
	 * We can only generate handles for inodes residing on a XFS filesystem,
	 * and only for regular files, directories or symbolic links.
	 */
	error = -EINVAL;
	if (inode->i_sb->s_magic != XFS_SB_MAGIC)
		goto out_put;

	error = -EBADF;
	if (!S_ISREG(inode->i_mode) &&
	    !S_ISDIR(inode->i_mode) &&
	    !S_ISLNK(inode->i_mode))
		goto out_put;


	memcpy(&handle.ha_fsid, ip->i_mount->m_fixedfsid, sizeof(xfs_fsid_t));

	if (cmd == XFS_IOC_PATH_TO_FSHANDLE) {
		/*
		 * This handle only contains an fsid, zero the rest.
		 */
		memset(&handle.ha_fid, 0, sizeof(handle.ha_fid));
		hsize = sizeof(xfs_fsid_t);
	} else {
		int		lock_mode;

		lock_mode = xfs_ilock_map_shared(ip);
		handle.ha_fid.fid_len = sizeof(xfs_fid_t) -
					sizeof(handle.ha_fid.fid_len);
		handle.ha_fid.fid_pad = 0;
		handle.ha_fid.fid_gen = ip->i_d.di_gen;
		handle.ha_fid.fid_ino = ip->i_ino;
		xfs_iunlock_map_shared(ip, lock_mode);

		hsize = XFS_HSIZE(handle);
	}

	error = -EFAULT;
	if (copy_to_user(hreq->ohandle, &handle, hsize) ||
	    copy_to_user(hreq->ohandlen, &hsize, sizeof(__s32)))
		goto out_put;

	error = 0;

 out_put:
	if (cmd == XFS_IOC_FD_TO_HANDLE)
		fdput(f);
	else
		path_put(&path);
	return error;
}
예제 #3
0
/*
 * xfs_find_handle maps from userspace xfs_fsop_handlereq structure to
 * a file or fs handle.
 *
 * XFS_IOC_PATH_TO_FSHANDLE
 *    returns fs handle for a mount point or path within that mount point
 * XFS_IOC_FD_TO_HANDLE
 *    returns full handle for a FD opened in user space
 * XFS_IOC_PATH_TO_HANDLE
 *    returns full handle for a path
 */
STATIC int
xfs_find_handle(
	unsigned int		cmd,
	unsigned long		arg)
{
	int			hsize;
	xfs_handle_t		handle;
	xfs_fsop_handlereq_t	hreq;
	struct inode		*inode;
	struct vnode		*vp;

	if (copy_from_user(&hreq, (xfs_fsop_handlereq_t *)arg, sizeof(hreq)))
		return -XFS_ERROR(EFAULT);

	memset((char *)&handle, 0, sizeof(handle));

	switch (cmd) {
	case XFS_IOC_PATH_TO_FSHANDLE:
	case XFS_IOC_PATH_TO_HANDLE: {
		struct nameidata	nd;
		int			error;

		error = user_path_walk_link(hreq.path, &nd);
		if (error)
			return error;

		ASSERT(nd.dentry);
		ASSERT(nd.dentry->d_inode);
		inode = igrab(nd.dentry->d_inode);
		path_release(&nd);
		break;
	}

	case XFS_IOC_FD_TO_HANDLE: {
		struct file	*file;

		file = fget(hreq.fd);
		if (!file)
		    return -EBADF;

		ASSERT(file->f_dentry);
		ASSERT(file->f_dentry->d_inode);
		inode = igrab(file->f_dentry->d_inode);
		fput(file);
		break;
	}

	default:
		ASSERT(0);
		return -XFS_ERROR(EINVAL);
	}

	if (inode->i_sb->s_magic != XFS_SB_MAGIC) {
		/* we're not in XFS anymore, Toto */
		iput(inode);
		return -XFS_ERROR(EINVAL);
	}

	/* we need the vnode */
	vp = LINVFS_GET_VP(inode);
	if (vp->v_type != VREG && vp->v_type != VDIR && vp->v_type != VLNK) {
		iput(inode);
		return -XFS_ERROR(EBADF);
	}

	/* now we can grab the fsid */
	memcpy(&handle.ha_fsid, vp->v_vfsp->vfs_altfsid, sizeof(xfs_fsid_t));
	hsize = sizeof(xfs_fsid_t);

	if (cmd != XFS_IOC_PATH_TO_FSHANDLE) {
		xfs_inode_t	*ip;
		bhv_desc_t	*bhv;
		int		lock_mode;

		/* need to get access to the xfs_inode to read the generation */
		bhv = vn_bhv_lookup_unlocked(VN_BHV_HEAD(vp), &xfs_vnodeops);
		ASSERT(bhv);
		ip = XFS_BHVTOI(bhv);
		ASSERT(ip);
		lock_mode = xfs_ilock_map_shared(ip);

		/* fill in fid section of handle from inode */
		handle.ha_fid.xfs_fid_len = sizeof(xfs_fid_t) -
					    sizeof(handle.ha_fid.xfs_fid_len);
		handle.ha_fid.xfs_fid_pad = 0;
		handle.ha_fid.xfs_fid_gen = ip->i_d.di_gen;
		handle.ha_fid.xfs_fid_ino = ip->i_ino;

		xfs_iunlock_map_shared(ip, lock_mode);

		hsize = XFS_HSIZE(handle);
	}

	/* now copy our handle into the user buffer & write out the size */
	if (copy_to_user((xfs_handle_t *)hreq.ohandle, &handle, hsize) ||
	    copy_to_user(hreq.ohandlen, &hsize, sizeof(__s32))) {
		iput(inode);
		return -XFS_ERROR(EFAULT);
	}

	iput(inode);
	return 0;
}
예제 #4
0
STATIC loff_t
xfs_seek_data(
	struct file		*file,
	loff_t			start,
	u32			type)
{
	struct inode		*inode = file->f_mapping->host;
	struct xfs_inode	*ip = XFS_I(inode);
	struct xfs_mount	*mp = ip->i_mount;
	struct xfs_bmbt_irec	map[2];
	int			nmap = 2;
	loff_t			uninitialized_var(offset);
	xfs_fsize_t		isize;
	xfs_fileoff_t		fsbno;
	xfs_filblks_t		end;
	uint			lock;
	int			error;

	lock = xfs_ilock_map_shared(ip);

	isize = i_size_read(inode);
	if (start >= isize) {
		error = ENXIO;
		goto out_unlock;
	}

	fsbno = XFS_B_TO_FSBT(mp, start);

	/*
	 * Try to read extents from the first block indicated
	 * by fsbno to the end block of the file.
	 */
	end = XFS_B_TO_FSB(mp, isize);

	error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap,
			       XFS_BMAPI_ENTIRE);
	if (error)
		goto out_unlock;

	/*
	 * Treat unwritten extent as data extent since it might
	 * contains dirty data in page cache.
	 */
	if (map[0].br_startblock != HOLESTARTBLOCK) {
		offset = max_t(loff_t, start,
			       XFS_FSB_TO_B(mp, map[0].br_startoff));
	} else {
		if (nmap == 1) {
			error = ENXIO;
			goto out_unlock;
		}

		offset = max_t(loff_t, start,
			       XFS_FSB_TO_B(mp, map[1].br_startoff));
	}

	if (offset != file->f_pos)
		file->f_pos = offset;

out_unlock:
	xfs_iunlock_map_shared(ip, lock);

	if (error)
		return -error;
	return offset;
}
예제 #5
0
/*
 * The following routine will acquire the locks required for a rename
 * operation. The code understands the semantics of renames and will
 * validate that name1 exists under dp1 & that name2 may or may not
 * exist under dp2.
 *
 * We are renaming dp1/name1 to dp2/name2.
 *
 * Return ENOENT if dp1 does not exist, other lookup errors, or 0 for success.
 */
STATIC int
xfs_lock_for_rename(
	xfs_inode_t	*dp1,	/* old (source) directory inode */
	xfs_inode_t	*dp2,	/* new (target) directory inode */
	bhv_vname_t	*vname1,/* old entry name */
	bhv_vname_t	*vname2,/* new entry name */
	xfs_inode_t	**ipp1,	/* inode of old entry */
	xfs_inode_t	**ipp2,	/* inode of new entry, if it
				   already exists, NULL otherwise. */
	xfs_inode_t	**i_tab,/* array of inode returned, sorted */
	int		*num_inodes)  /* number of inodes in array */
{
	xfs_inode_t		*ip1, *ip2, *temp;
	xfs_ino_t		inum1, inum2;
	int			error;
	int			i, j;
	uint			lock_mode;
	int			diff_dirs = (dp1 != dp2);

	ip2 = NULL;

	/*
	 * First, find out the current inums of the entries so that we
	 * can determine the initial locking order.  We'll have to
	 * sanity check stuff after all the locks have been acquired
	 * to see if we still have the right inodes, directories, etc.
	 */
	lock_mode = xfs_ilock_map_shared(dp1);
	error = xfs_get_dir_entry(vname1, &ip1);
	if (error) {
		xfs_iunlock_map_shared(dp1, lock_mode);
		return error;
	}

	inum1 = ip1->i_ino;

	ASSERT(ip1);
	ITRACE(ip1);

	/*
	 * Unlock dp1 and lock dp2 if they are different.
	 */

	if (diff_dirs) {
		xfs_iunlock_map_shared(dp1, lock_mode);
		lock_mode = xfs_ilock_map_shared(dp2);
	}

	error = xfs_dir_lookup_int(XFS_ITOBHV(dp2), lock_mode,
				   vname2, &inum2, &ip2);
	if (error == ENOENT) {		/* target does not need to exist. */
		inum2 = 0;
	} else if (error) {
		/*
		 * If dp2 and dp1 are the same, the next line unlocks dp1.
		 * Got it?
		 */
		xfs_iunlock_map_shared(dp2, lock_mode);
		IRELE (ip1);
		return error;
	} else {
		ITRACE(ip2);
	}

	/*
	 * i_tab contains a list of pointers to inodes.  We initialize
	 * the table here & we'll sort it.  We will then use it to
	 * order the acquisition of the inode locks.
	 *
	 * Note that the table may contain duplicates.  e.g., dp1 == dp2.
	 */
	i_tab[0] = dp1;
	i_tab[1] = dp2;
	i_tab[2] = ip1;
	if (inum2 == 0) {
		*num_inodes = 3;
		i_tab[3] = NULL;
	} else {
		*num_inodes = 4;
		i_tab[3] = ip2;
	}

	/*
	 * Sort the elements via bubble sort.  (Remember, there are at
	 * most 4 elements to sort, so this is adequate.)
	 */
	for (i=0; i < *num_inodes; i++) {
		for (j=1; j < *num_inodes; j++) {
			if (i_tab[j]->i_ino < i_tab[j-1]->i_ino) {
				temp = i_tab[j];
				i_tab[j] = i_tab[j-1];
				i_tab[j-1] = temp;
			}
		}
	}

	/*
	 * We have dp2 locked. If it isn't first, unlock it.
	 * If it is first, tell xfs_lock_inodes so it can skip it
	 * when locking. if dp1 == dp2, xfs_lock_inodes will skip both
	 * since they are equal. xfs_lock_inodes needs all these inodes
	 * so that it can unlock and retry if there might be a dead-lock
	 * potential with the log.
	 */

	if (i_tab[0] == dp2 && lock_mode == XFS_ILOCK_SHARED) {
#ifdef DEBUG
		xfs_rename_skip++;
#endif
		xfs_lock_inodes(i_tab, *num_inodes, 1, XFS_ILOCK_SHARED);
	} else {
#ifdef DEBUG
		xfs_rename_nskip++;
#endif
		xfs_iunlock_map_shared(dp2, lock_mode);
		xfs_lock_inodes(i_tab, *num_inodes, 0, XFS_ILOCK_SHARED);
	}

	/*
	 * Set the return value. Null out any unused entries in i_tab.
	 */
	*ipp1 = *ipp2 = NULL;
	for (i=0; i < *num_inodes; i++) {
		if (i_tab[i]->i_ino == inum1) {
			*ipp1 = i_tab[i];
		}
		if (i_tab[i]->i_ino == inum2) {
			*ipp2 = i_tab[i];
		}
	}
	for (;i < 4; i++) {
		i_tab[i] = NULL;
	}
	return 0;
}
예제 #6
0
파일: xfs_ioctl.c 프로젝트: Mr-Aloof/wl500g
/*
 * xfs_find_handle maps from userspace xfs_fsop_handlereq structure to
 * a file or fs handle.
 *
 * XFS_IOC_PATH_TO_FSHANDLE
 *    returns fs handle for a mount point or path within that mount point
 * XFS_IOC_FD_TO_HANDLE
 *    returns full handle for a FD opened in user space
 * XFS_IOC_PATH_TO_HANDLE
 *    returns full handle for a path
 */
STATIC int
xfs_find_handle(
	unsigned int		cmd,
	void			__user *arg)
{
	int			hsize;
	xfs_handle_t		handle;
	xfs_fsop_handlereq_t	hreq;
	struct inode		*inode;

	if (copy_from_user(&hreq, arg, sizeof(hreq)))
		return -XFS_ERROR(EFAULT);

	memset((char *)&handle, 0, sizeof(handle));

	switch (cmd) {
	case XFS_IOC_PATH_TO_FSHANDLE:
	case XFS_IOC_PATH_TO_HANDLE: {
		struct nameidata	nd;
		int			error;

		error = user_path_walk_link((const char __user *)hreq.path, &nd);
		if (error)
			return error;

		ASSERT(nd.path.dentry);
		ASSERT(nd.path.dentry->d_inode);
		inode = igrab(nd.path.dentry->d_inode);
		path_put(&nd.path);
		break;
	}

	case XFS_IOC_FD_TO_HANDLE: {
		struct file	*file;

		file = fget(hreq.fd);
		if (!file)
		    return -EBADF;

		ASSERT(file->f_path.dentry);
		ASSERT(file->f_path.dentry->d_inode);
		inode = igrab(file->f_path.dentry->d_inode);
		fput(file);
		break;
	}

	default:
		ASSERT(0);
		return -XFS_ERROR(EINVAL);
	}

	if (inode->i_sb->s_magic != XFS_SB_MAGIC) {
		/* we're not in XFS anymore, Toto */
		iput(inode);
		return -XFS_ERROR(EINVAL);
	}

	switch (inode->i_mode & S_IFMT) {
	case S_IFREG:
	case S_IFDIR:
	case S_IFLNK:
		break;
	default:
		iput(inode);
		return -XFS_ERROR(EBADF);
	}

	/* now we can grab the fsid */
	memcpy(&handle.ha_fsid, XFS_I(inode)->i_mount->m_fixedfsid,
			sizeof(xfs_fsid_t));
	hsize = sizeof(xfs_fsid_t);

	if (cmd != XFS_IOC_PATH_TO_FSHANDLE) {
		xfs_inode_t	*ip = XFS_I(inode);
		int		lock_mode;

		/* need to get access to the xfs_inode to read the generation */
		lock_mode = xfs_ilock_map_shared(ip);

		/* fill in fid section of handle from inode */
		handle.ha_fid.fid_len = sizeof(xfs_fid_t) -
					sizeof(handle.ha_fid.fid_len);
		handle.ha_fid.fid_pad = 0;
		handle.ha_fid.fid_gen = ip->i_d.di_gen;
		handle.ha_fid.fid_ino = ip->i_ino;

		xfs_iunlock_map_shared(ip, lock_mode);

		hsize = XFS_HSIZE(handle);
	}

	/* now copy our handle into the user buffer & write out the size */
	if (copy_to_user(hreq.ohandle, &handle, hsize) ||
	    copy_to_user(hreq.ohandlen, &hsize, sizeof(__s32))) {
		iput(inode);
		return -XFS_ERROR(EFAULT);
	}

	iput(inode);
	return 0;
}
예제 #7
0
STATIC loff_t
xfs_seek_hole(
	struct file		*file,
	loff_t			start)
{
	struct inode		*inode = file->f_mapping->host;
	struct xfs_inode	*ip = XFS_I(inode);
	struct xfs_mount	*mp = ip->i_mount;
	loff_t			uninitialized_var(offset);
	xfs_fsize_t		isize;
	xfs_fileoff_t		fsbno;
	xfs_filblks_t		end;
	uint			lock;
	int			error;

	if (XFS_FORCED_SHUTDOWN(mp))
		return -XFS_ERROR(EIO);

	lock = xfs_ilock_map_shared(ip);

	isize = i_size_read(inode);
	if (start >= isize) {
		error = ENXIO;
		goto out_unlock;
	}

	fsbno = XFS_B_TO_FSBT(mp, start);
	end = XFS_B_TO_FSB(mp, isize);

	for (;;) {
		struct xfs_bmbt_irec	map[2];
		int			nmap = 2;
		unsigned int		i;

		error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap,
				       XFS_BMAPI_ENTIRE);
		if (error)
			goto out_unlock;

		/* No extents at given offset, must be beyond EOF */
		if (nmap == 0) {
			error = ENXIO;
			goto out_unlock;
		}

		for (i = 0; i < nmap; i++) {
			offset = max_t(loff_t, start,
				       XFS_FSB_TO_B(mp, map[i].br_startoff));

			/* Landed in a hole */
			if (map[i].br_startblock == HOLESTARTBLOCK)
				goto out;

			/*
			 * Landed in an unwritten extent, try to search hole
			 * from page cache.
			 */
			if (map[i].br_state == XFS_EXT_UNWRITTEN) {
				if (xfs_find_get_desired_pgoff(inode, &map[i],
							HOLE_OFF, &offset))
					goto out;
			}
		}

		/*
		 * map[0] contains data or its unwritten but contains
		 * data in page cache, probably means that we are
		 * reading after EOF.  We should fix offset to point
		 * to the end of the file(i.e., there is an implicit
		 * hole at the end of any file).
		 */
		if (nmap == 1) {
			offset = isize;
			break;
		}

		ASSERT(i > 1);

		/*
		 * Both mappings contains data, proceed to the next round of
		 * search if the current reading offset not beyond or hit EOF.
		 */
		fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
		start = XFS_FSB_TO_B(mp, fsbno);
		if (start >= isize) {
			offset = isize;
			break;
		}
	}

out:
	/*
	 * At this point, we must have found a hole.  However, the returned
	 * offset may be bigger than the file size as it may be aligned to
	 * page boundary for unwritten extents, we need to deal with this
	 * situation in particular.
	 */
	offset = min_t(loff_t, offset, isize);
	offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);

out_unlock:
	xfs_iunlock_map_shared(ip, lock);

	if (error)
		return -error;
	return offset;
}
예제 #8
0
STATIC loff_t
xfs_seek_data(
	struct file		*file,
	loff_t			start)
{
	struct inode		*inode = file->f_mapping->host;
	struct xfs_inode	*ip = XFS_I(inode);
	struct xfs_mount	*mp = ip->i_mount;
	loff_t			uninitialized_var(offset);
	xfs_fsize_t		isize;
	xfs_fileoff_t		fsbno;
	xfs_filblks_t		end;
	uint			lock;
	int			error;

	lock = xfs_ilock_map_shared(ip);

	isize = i_size_read(inode);
	if (start >= isize) {
		error = ENXIO;
		goto out_unlock;
	}

	/*
	 * Try to read extents from the first block indicated
	 * by fsbno to the end block of the file.
	 */
	fsbno = XFS_B_TO_FSBT(mp, start);
	end = XFS_B_TO_FSB(mp, isize);
	for (;;) {
		struct xfs_bmbt_irec	map[2];
		int			nmap = 2;
		unsigned int		i;

		error = xfs_bmapi_read(ip, fsbno, end - fsbno, map, &nmap,
				       XFS_BMAPI_ENTIRE);
		if (error)
			goto out_unlock;

		/* No extents at given offset, must be beyond EOF */
		if (nmap == 0) {
			error = ENXIO;
			goto out_unlock;
		}

		for (i = 0; i < nmap; i++) {
			offset = max_t(loff_t, start,
				       XFS_FSB_TO_B(mp, map[i].br_startoff));

			/* Landed in a data extent */
			if (map[i].br_startblock == DELAYSTARTBLOCK ||
			    (map[i].br_state == XFS_EXT_NORM &&
			     !isnullstartblock(map[i].br_startblock)))
				goto out;

			/*
			 * Landed in an unwritten extent, try to search data
			 * from page cache.
			 */
			if (map[i].br_state == XFS_EXT_UNWRITTEN) {
				if (xfs_find_get_desired_pgoff(inode, &map[i],
							DATA_OFF, &offset))
					goto out;
			}
		}

		/*
		 * map[0] is hole or its an unwritten extent but
		 * without data in page cache.  Probably means that
		 * we are reading after EOF if nothing in map[1].
		 */
		if (nmap == 1) {
			error = ENXIO;
			goto out_unlock;
		}

		ASSERT(i > 1);

		/*
		 * Nothing was found, proceed to the next round of search
		 * if reading offset not beyond or hit EOF.
		 */
		fsbno = map[i - 1].br_startoff + map[i - 1].br_blockcount;
		start = XFS_FSB_TO_B(mp, fsbno);
		if (start >= isize) {
			error = ENXIO;
			goto out_unlock;
		}
	}

out:
	offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes);

out_unlock:
	xfs_iunlock_map_shared(ip, lock);

	if (error)
		return -error;
	return offset;
}