On Tue, Jul 23, 2024 at 09:59:41AM -0500, Eric Sandeen wrote: > We got a report from the podman folks that selinux relabels that happen > as part of their process were returning ENOSPC when the filesystem is > completely full. This is because xattr changes reserve about 15 blocks > for the worst case, but the common case is for selinux contexts to be > the sole, in-inode xattr and consume no blocks. > > We already allow reserved space consumption for XFS_ATTR_ROOT for things > such as ACLs, and SECURE namespace attributes are not so very different, > so allow them to use the reserved space as well. > > Code-comment-by: Dave Chinner <dchinner@xxxxxxxxxx> > Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx> > --- > > V2: Remove local variable, add comment. > V3: Add Dave's preferred comment > > diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c > index ab3d22f662f2..85e7be094943 100644 > --- a/fs/xfs/xfs_xattr.c > +++ b/fs/xfs/xfs_xattr.c > @@ -110,7 +110,26 @@ xfs_attr_change( > args->whichfork = XFS_ATTR_FORK; > xfs_attr_sethash(args); > > - return xfs_attr_set(args, op, args->attr_filter & XFS_ATTR_ROOT); > + /* > + * Some xattrs must be resistent to allocation failure at Nit: resistant > + * ENOSPC. e.g. creating an inode with ACLs or security > + * attributes requires the allocation of the xattr holding > + * that information to succeed. Hence we allow xattrs in the > + * VFS TRUSTED, SYSTEM, POSIX_ACL and SECURITY (LSM xattr) > + * namespaces to dip into the reserve block pool to allow > + * manipulation of these xattrs when at ENOSPC. These VFS > + * xattr namespaces translate to the XFS_ATTR_ROOT and > + * XFS_ATTR_SECURE on-disk namespaces. > + * > + * For most of these cases, these special xattrs will fit in > + * the inode itself and so consume no extra space or only > + * require temporary extra space while an overwrite is being > + * made. Hence the use of the reserved pool is largely to > + * avoid the worst case reservation from preventing the > + * xattr from being created at ENOSPC. > + */ > + return xfs_attr_set(args, op, > + args->attr_filter & (XFS_ATTR_ROOT | XFS_ATTR_SECURE)); With that fixed, Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx> --D > } > > > > >
