Commit 8b85dc40 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: check if an open file is on the health monitored fs 



Create a new ioctl for the healthmon file that checks that a given fd
points to the same filesystem that the healthmon file is monitoring.
This allows xfs_healer to check that when it reopens a mountpoint to
perform repairs, the file that it gets matches the filesystem that
generated the corruption report.

(Note that xfs_healer doesn't maintain an open fd to a filesystem that
it's monitoring so that it doesn't pin the mount.)

Signed-off-by: default avatar"Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
parent c0e719cb

fs/xfs/libxfs/xfs_fs.h

+11 −1
Original line number Diff line number Diff line
@@ -1151,6 +1151,15 @@ struct xfs_health_monitor { 
/* Initial return format version */

#define XFS_HEALTH_MONITOR_FMT_V0	(0)



/*

 * Check that a given fd points to the same filesystem that the health monitor

 * is monitoring.

 */

struct xfs_health_file_on_monitored_fs {

	__s32		fd;

	__u32		flags;	/* zero for now */

};



/*

 * ioctl commands that are used by Linux filesystems

 */
@@ -1191,7 +1200,8 @@ struct xfs_health_monitor { 
#define XFS_IOC_SCRUBV_METADATA	_IOWR('X', 64, struct xfs_scrub_vec_head)

#define XFS_IOC_RTGROUP_GEOMETRY _IOWR('X', 65, struct xfs_rtgroup_geometry)

#define XFS_IOC_HEALTH_MONITOR	_IOW ('X', 68, struct xfs_health_monitor)



#define XFS_IOC_HEALTH_FD_ON_MONITORED_FS \

				_IOW ('X', 69, struct xfs_health_file_on_monitored_fs)

/*

 * ioctl commands that replace IRIX syssgi()'s

 */

fs/xfs/xfs_healthmon.c

+34 −0
Original line number Diff line number Diff line
@@ -1090,6 +1090,38 @@ xfs_healthmon_reconfigure( 
	return 0;

}



/* Does the fd point to the same filesystem as the one we're monitoring? */

STATIC long

xfs_healthmon_file_on_monitored_fs(

	struct file			*file,

	unsigned int			cmd,

	void __user			*arg)

{

	struct xfs_health_file_on_monitored_fs hms;

	struct xfs_healthmon		*hm = file->private_data;

	struct inode			*hms_inode;



	if (copy_from_user(&hms, arg, sizeof(hms)))

		return -EFAULT;



	if (hms.flags)

		return -EINVAL;



	CLASS(fd, hms_fd)(hms.fd);

	if (fd_empty(hms_fd))

		return -EBADF;



	hms_inode = file_inode(fd_file(hms_fd));

	mutex_lock(&hm->lock);

	if (hm->mount_cookie != (uintptr_t)hms_inode->i_sb) {

		mutex_unlock(&hm->lock);

		return -ESTALE;

	}



	mutex_unlock(&hm->lock);

	return 0;

}



/* Handle ioctls for the health monitoring thread. */

STATIC long

xfs_healthmon_ioctl(
@@ -1102,6 +1134,8 @@ xfs_healthmon_ioctl( 
	switch (cmd) {

	case XFS_IOC_HEALTH_MONITOR:

		return xfs_healthmon_reconfigure(file, cmd, arg);

	case XFS_IOC_HEALTH_FD_ON_MONITORED_FS:

		return xfs_healthmon_file_on_monitored_fs(file, cmd, arg);

	default:

		break;

	}