| Message ID | 157062067944.32346.8228418435930532076.stgit@fedora-28 (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | xfs: mount API patch series | expand |
On Wed, Oct 09, 2019 at 07:31:19PM +0800, Ian Kent wrote: > Add the fs_context_operations method .reconfigure that performs > remount validation as previously done by the super_operations > .remount_fs method. > > Signed-off-by: Ian Kent <raven@themaw.net> > --- Reviewed-by: Brian Foster <bfoster@redhat.com> > fs/xfs/xfs_super.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 62 insertions(+) > > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index 7e634706626b..230b0e2a184c 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -1544,6 +1544,67 @@ xfs_fs_remount( > return 0; > } > > +/* > + * Logically we would return an error here to prevent users > + * from believing they might have changed mount options using > + * remount which can't be changed. > + * > + * But unfortunately mount(8) adds all options from mtab and > + * fstab to the mount arguments in some cases so we can't > + * blindly reject options, but have to check for each specified > + * option if it actually differs from the currently set option > + * and only reject it if that's the case. > + * > + * Until that is implemented we return success for every remount > + * request, and silently ignore all options that we can't actually > + * change. > + */ > +STATIC int > +xfs_reconfigure( > + struct fs_context *fc) > +{ > + struct xfs_fs_context *ctx = fc->fs_private; > + struct xfs_mount *mp = XFS_M(fc->root->d_sb); > + struct xfs_mount *new_mp = fc->s_fs_info; > + xfs_sb_t *sbp = &mp->m_sb; > + int flags = fc->sb_flags; > + int error; > + > + error = xfs_validate_params(new_mp, ctx, false); > + if (error) > + return error; > + > + /* inode32 -> inode64 */ > + if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && > + !(new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) { > + mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS; > + mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount); > + } > + > + /* inode64 -> inode32 */ > + if (!(mp->m_flags & XFS_MOUNT_SMALL_INUMS) && > + (new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) { > + mp->m_flags |= XFS_MOUNT_SMALL_INUMS; > + mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount); > + } > + > + /* ro -> rw */ > + if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(flags & SB_RDONLY)) { > + error = xfs_remount_rw(mp); > + if (error) > + return error; > + } > + > + /* rw -> ro */ > + if (!(mp->m_flags & XFS_MOUNT_RDONLY) && (flags & SB_RDONLY)) { > + error = xfs_remount_ro(mp); > + if (error) > + return error; > + } > + > + return 0; > +} > + > /* > * Second stage of a freeze. The data is already frozen so we only > * need to take care of the metadata. Once that's done sync the superblock > @@ -2069,6 +2130,7 @@ static const struct super_operations xfs_super_operations = { > static const struct fs_context_operations xfs_context_ops = { > .parse_param = xfs_parse_param, > .get_tree = xfs_get_tree, > + .reconfigure = xfs_reconfigure, > }; > > static struct file_system_type xfs_fs_type = { >
> +/* > + * Logically we would return an error here to prevent users > + * from believing they might have changed mount options using > + * remount which can't be changed. > + * > + * But unfortunately mount(8) adds all options from mtab and > + * fstab to the mount arguments in some cases so we can't > + * blindly reject options, but have to check for each specified > + * option if it actually differs from the currently set option > + * and only reject it if that's the case. > + * > + * Until that is implemented we return success for every remount > + * request, and silently ignore all options that we can't actually > + * change. > + */ Please use up all 80 chars available for your comments.
On Wed, 2019-10-09 at 08:05 -0700, Christoph Hellwig wrote: > > +/* > > + * Logically we would return an error here to prevent users > > + * from believing they might have changed mount options using > > + * remount which can't be changed. > > + * > > + * But unfortunately mount(8) adds all options from mtab and > > + * fstab to the mount arguments in some cases so we can't > > + * blindly reject options, but have to check for each specified > > + * option if it actually differs from the currently set option > > + * and only reject it if that's the case. > > + * > > + * Until that is implemented we return success for every remount > > + * request, and silently ignore all options that we can't actually > > + * change. > > + */ > > Please use up all 80 chars available for your comments. Will do. Ian
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 7e634706626b..230b0e2a184c 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1544,6 +1544,67 @@ xfs_fs_remount( return 0; } +/* + * Logically we would return an error here to prevent users + * from believing they might have changed mount options using + * remount which can't be changed. + * + * But unfortunately mount(8) adds all options from mtab and + * fstab to the mount arguments in some cases so we can't + * blindly reject options, but have to check for each specified + * option if it actually differs from the currently set option + * and only reject it if that's the case. + * + * Until that is implemented we return success for every remount + * request, and silently ignore all options that we can't actually + * change. + */ +STATIC int +xfs_reconfigure( + struct fs_context *fc) +{ + struct xfs_fs_context *ctx = fc->fs_private; + struct xfs_mount *mp = XFS_M(fc->root->d_sb); + struct xfs_mount *new_mp = fc->s_fs_info; + xfs_sb_t *sbp = &mp->m_sb; + int flags = fc->sb_flags; + int error; + + error = xfs_validate_params(new_mp, ctx, false); + if (error) + return error; + + /* inode32 -> inode64 */ + if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && + !(new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) { + mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS; + mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount); + } + + /* inode64 -> inode32 */ + if (!(mp->m_flags & XFS_MOUNT_SMALL_INUMS) && + (new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) { + mp->m_flags |= XFS_MOUNT_SMALL_INUMS; + mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount); + } + + /* ro -> rw */ + if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(flags & SB_RDONLY)) { + error = xfs_remount_rw(mp); + if (error) + return error; + } + + /* rw -> ro */ + if (!(mp->m_flags & XFS_MOUNT_RDONLY) && (flags & SB_RDONLY)) { + error = xfs_remount_ro(mp); + if (error) + return error; + } + + return 0; +} + /* * Second stage of a freeze. The data is already frozen so we only * need to take care of the metadata. Once that's done sync the superblock @@ -2069,6 +2130,7 @@ static const struct super_operations xfs_super_operations = { static const struct fs_context_operations xfs_context_ops = { .parse_param = xfs_parse_param, .get_tree = xfs_get_tree, + .reconfigure = xfs_reconfigure, }; static struct file_system_type xfs_fs_type = {
Add the fs_context_operations method .reconfigure that performs remount validation as previously done by the super_operations .remount_fs method. Signed-off-by: Ian Kent <raven@themaw.net> --- fs/xfs/xfs_super.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+)