1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * Copyright (c) 2021-2024 Oracle.  All Rights Reserved.
35  * Live Inode Link Count Repair
38  * Use the live inode link count information that we collected to replace the
39  * nlink values of the incore inodes.  A scrub->repair cycle should have left
44 /* Set up to repair inode link counts. */
53  * Inodes that aren't the root directory or the orphanage, have a nonzero link
63 	struct xfs_mount	*mp = ip->i_mount;  in xrep_nlinks_is_orphaned()
65 	if (obs->parents != 0)  in xrep_nlinks_is_orphaned()
67 	if (ip == mp->m_rootip || ip == sc->orphanage)  in xrep_nlinks_is_orphaned()
80 	pag = xfs_perag_get(sc->mp, XFS_INO_TO_AGNO(sc->mp, sc->ip->i_ino));  in xrep_nlinks_iunlink_remove()
81 	error = xfs_iunlink_remove(sc->tp, pag, sc->ip);  in xrep_nlinks_iunlink_remove()
87  * Correct the link count of the given inode.  Because we have to grab locks
88  * and resources in a certain order, it's possible that this will be a no-op.
95 	struct xfs_scrub	*sc = xnc->sc;  in xrep_nlinks_repair_inode()
96 	struct xfs_mount	*mp = sc->mp;  in xrep_nlinks_repair_inode()
97 	struct xfs_inode	*ip = sc->ip;  in xrep_nlinks_repair_inode()
106 	 * they're correct for non-directories, and the directory repair code  in xrep_nlinks_repair_inode()
107 	 * doesn't bump the link counts for the children.  in xrep_nlinks_repair_inode()
114 	 * prepare for a link count repair that could involve @ip being adopted  in xrep_nlinks_repair_inode()
122 		error = xrep_adoption_trans_alloc(sc, &xnc->adoption);  in xrep_nlinks_repair_inode()
134 	 * need for a simple link count update, since that's much more common.  in xrep_nlinks_repair_inode()
139 		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_link, 0, 0, 0,  in xrep_nlinks_repair_inode()
140 				&sc->tp);  in xrep_nlinks_repair_inode()
147 		xfs_trans_ijoin(sc->tp, ip, 0);  in xrep_nlinks_repair_inode()
150 	mutex_lock(&xnc->lock);  in xrep_nlinks_repair_inode()
152 	if (xchk_iscan_aborted(&xnc->collect_iscan)) {  in xrep_nlinks_repair_inode()
153 		error = -ECANCELED;  in xrep_nlinks_repair_inode()
157 	error = xfarray_load_sparse(xnc->nlinks, ip->i_ino, &obs);  in xrep_nlinks_repair_inode()
163 	 * We still hold @ip's ILOCK, so its link count cannot change.  in xrep_nlinks_repair_inode()
165 	mutex_unlock(&xnc->lock);  in xrep_nlinks_repair_inode()
168 	actual_nlink = VFS_I(ip)->i_nlink;  in xrep_nlinks_repair_inode()
171 	 * Non-directories cannot have directories pointing up to them.  in xrep_nlinks_repair_inode()
177 	 * store.  This is a never-ending and stupid battle; both tools missed  in xrep_nlinks_repair_inode()
180 	if (!S_ISDIR(VFS_I(ip)->i_mode) && obs.children != 0) {  in xrep_nlinks_repair_inode()
188 	 * up the incore link counts if we are.  in xrep_nlinks_repair_inode()
193 		error = xrep_adoption_compute_name(&xnc->adoption, &xnc->xname);  in xrep_nlinks_repair_inode()
202 		error = xrep_adoption_move(&xnc->adoption);  in xrep_nlinks_repair_inode()
207 		 * Re-read the link counts since the reparenting will have  in xrep_nlinks_repair_inode()
210 		mutex_lock(&xnc->lock);  in xrep_nlinks_repair_inode()
211 		error = xfarray_load_sparse(xnc->nlinks, ip->i_ino, &obs);  in xrep_nlinks_repair_inode()
212 		mutex_unlock(&xnc->lock);  in xrep_nlinks_repair_inode()
217 		actual_nlink = VFS_I(ip)->i_nlink;  in xrep_nlinks_repair_inode()
237 		error = xfs_iunlink(sc->tp, ip);  in xrep_nlinks_repair_inode()
243 	/* Commit the new link count if it changed. */  in xrep_nlinks_repair_inode()
257 	xfs_trans_log_inode(sc->tp, ip, XFS_ILOG_CORE);  in xrep_nlinks_repair_inode()
263 	mutex_unlock(&xnc->lock);  in xrep_nlinks_repair_inode()
288 		error = xchk_iscan_iter(&xnc->compare_iscan, ipp);  in xrep_nlinks_iter()
289 	} while (error == -EBUSY);  in xrep_nlinks_iter()
294 /* Commit the new inode link counters. */
299 	struct xchk_nlink_ctrs	*xnc = sc->buf;  in xrep_nlinks()
304 	 * subdirectory links.  Child subdirectories with a back link (dotdot  in xrep_nlinks()
305 	 * entry) but no forward link are moved to the orphanage, so we cannot  in xrep_nlinks()
306 	 * repair the link count of the parent directory based on the back link  in xrep_nlinks()
310 	if (!xfs_has_ftype(sc->mp))  in xrep_nlinks()
311 		return -EOPNOTSUPP;  in xrep_nlinks()
315 	 * link counts.  Retry iget every tenth of a second for up to 30  in xrep_nlinks()
316 	 * seconds -- even if repair misses a few inodes, we still try to fix  in xrep_nlinks()
319 	xchk_iscan_start(sc, 30000, 100, &xnc->compare_iscan);  in xrep_nlinks()
320 	ASSERT(sc->ip == NULL);  in xrep_nlinks()
322 	while ((error = xrep_nlinks_iter(xnc, &sc->ip)) == 1) {  in xrep_nlinks()
330 		xchk_iscan_mark_visited(&xnc->compare_iscan, sc->ip);  in xrep_nlinks()
331 		xchk_irele(sc, sc->ip);  in xrep_nlinks()
332 		sc->ip = NULL;  in xrep_nlinks()
349 	xchk_iscan_iter_finish(&xnc->compare_iscan);  in xrep_nlinks()
350 	xchk_iscan_teardown(&xnc->compare_iscan);  in xrep_nlinks()