fs/overlayfs/super.c

33 	struct dentry *upper, *lower;
49 	upper = ovl_dentry_upper(dentry);
50 	if (upper && (type == D_REAL_METADATA ||
52 		return upper;
110 	struct dentry *upper;
120 	upper = ovl_i_dentry_upper(inode);
121 	if (upper)
122 		ret = ovl_revalidate_real(upper, flags, weak);
197 /* Sync real dirty inodes in upper filesystem (if it exists) */
243  * Get the filesystem statistics.  As writes always target the upper layer
244  * filesystem pass the statfs to the upper filesystem (if it exists)
337 		 * allowed as upper are limited to "normal" ones, where checking
488 		pr_err("upper fs is r/o, try multi-lower layers mount\n");
669 	 * workdir and upper are on same fs, we can do iterate_dir() on
679 		pr_warn("upper fs needs to support d_type.\n");
681 	/* Check if upper/work fs supports O_TMPFILE */
687 		pr_warn("upper fs does not support tmpfile.\n");
690 	/* Check if upper/work fs supports RENAME_WHITEOUT */
697 		pr_warn("upper fs does not support RENAME_WHITEOUT.\n");
700 	 * Check if upper/work fs supports (trusted|user).overlay.* xattr
704 		pr_warn("failed to set xattr on upper\n");
738 	 * We allowed sub-optimal upper fs configuration and don't want to break
739 	 * users over kernel upgrade, but we never allowed remote upper fs, so
740 	 * we can enforce strict requirements for remote upper fs.
744 		pr_err("upper fs missing required features.\n");
761 	/* Check if upper/work fs supports file handles */
765 		pr_warn("upper fs does not support file handles, falling back to index=off.\n");
769 	/* Check if upper fs has 32bit inode numbers */
834 	/* Verify lower root is upper root origin */
837 		pr_err("failed to verify upper root origin\n");
857 		 * Verify upper root is exclusively associated with index dir.
858 		 * Older kernels stored upper fh in ".overlay.origin"
860 		 * upper dir file handle. In any case, verify or set xattr
861 		 * ".overlay.upper" to indicate that index may have
874 			pr_err("failed to verify index dir 'upper' xattr\n");
903 	 * lower inode of non-dir upper.
994 	 * idx/fsid 0 are reserved for upper fs even with lower only overlay
1000 	 * All lower layers that share the same fs as upper layer, use the same
1001 	 * pseudo_dev as upper layer.  Allocate fs[0].pseudo_dev even for lower
1003 	 * is_lower will be set if upper fs is shared with a lower layer.
1007 		pr_err("failed to get anonymous bdev for upper fs\n");
1093 		 * fsid, where fsid 0 is reserved for upper fs (even with
1103 		pr_info("\"xino\" feature enabled using %d upper inode bits.\n",
1169  * - upper/work dir of any overlayfs instance
1258 		/* Root inode uses upper st_ino/i_ino */
1336 	 * Layer 0 is reserved for upper even if there's no upper.
1368 		err = ovl_get_upper(sb, ofs, &layers[0], &ctx->upper);
1382 		err = ovl_get_workdir(sb, ofs, &ctx->upper, &ctx->work);
1397 	/* If the upper fs is nonexistent, we mark overlayfs r/o too */
1402 		pr_warn("The uuid=off requires a single fs for lower and upper, falling back to uuid=null.\n");
1406 		ovl_init_uuid_xattr(sb, ofs, &ctx->upper);
1410 		err = ovl_get_indexdir(sb, ofs, oe, &ctx->upper);
1459 	 * for the the upper layer instead of overlayfs as that would
1466 	root_dentry = ovl_get_root(sb, ctx->upper.dentry, oe);