--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2023-2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@kernel.org>
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_log_format.h"
+#include "xfs_trans.h"
+#include "xfs_inode.h"
+#include "xfs_icache.h"
+#include "xfs_dir2.h"
+#include "xfs_dir2_priv.h"
+#include "xfs_attr.h"
+#include "xfs_parent.h"
+#include "scrub/scrub.h"
+#include "scrub/common.h"
+#include "scrub/bitmap.h"
+#include "scrub/ino_bitmap.h"
+#include "scrub/xfile.h"
+#include "scrub/xfarray.h"
+#include "scrub/xfblob.h"
+#include "scrub/listxattr.h"
+#include "scrub/trace.h"
+#include "scrub/dirtree.h"
+
+/*
+ * Directory Tree Structure Validation
+ * ===================================
+ *
+ * Validating the tree qualities of the directory tree structure can be
+ * difficult. If the tree is frozen, running a depth (or breadth) first search
+ * and marking a bitmap suffices to determine if there is a cycle. XORing the
+ * mark bitmap with the inode bitmap afterwards tells us if there are
+ * disconnected cycles. If the tree is not frozen, directory updates can move
+ * subtrees across the scanner wavefront, which complicates the design greatly.
+ *
+ * Directory parent pointers change that by enabling an incremental approach to
+ * validation of the tree structure. Instead of using one thread to scan the
+ * entire filesystem, we instead can have multiple threads walking individual
+ * subdirectories upwards to the root. In a perfect world, the IOLOCK would
+ * suffice to stabilize two directories in a parent -> child relationship.
+ * Unfortunately, the VFS does not take the IOLOCK when moving a child
+ * subdirectory, so we instead synchronize on ILOCK and use dirent update hooks
+ * to detect a race. If a race occurs in a path, we restart the scan.
+ *
+ * If the walk terminates without reaching the root, we know the path is
+ * disconnected and ought to be attached to the lost and found. If on the walk
+ * we find the same subdir that we're scanning, we know this is a cycle and
+ * should delete an incoming edge. If we find multiple paths to the root, we
+ * know to delete an incoming edge.
+ *
+ * There are two big hitches with this approach: first, all file link counts
+ * must be correct to prevent other writers from doing the wrong thing with the
+ * directory tree structure. Second, because we're walking upwards in a tree
+ * of arbitrary depth, we cannot hold all the ILOCKs. Instead, we will use a
+ * directory update hook to invalidate the scan results if one of the paths
+ * we've scanned has changed.
+ */
+
+/* Clean up the dirtree checking resources. */
+STATIC void
+xchk_dirtree_buf_cleanup(
+ void *buf)
+{
+ struct xchk_dirtree *dl = buf;
+ struct xchk_dirpath *path, *n;
+
+ xchk_dirtree_for_each_path_safe(dl, path, n) {
+ list_del_init(&path->list);
+ xino_bitmap_destroy(&path->seen_inodes);
+ kfree(path);
+ }
+
+ xfblob_destroy(dl->path_names);
+ xfarray_destroy(dl->path_steps);
+ mutex_destroy(&dl->lock);
+}
+
+/* Set us up to look for directory loops. */
+int
+xchk_setup_dirtree(
+ struct xfs_scrub *sc)
+{
+ struct xchk_dirtree *dl;
+ char *descr;
+ int error;
+
+ dl = kvzalloc(sizeof(struct xchk_dirtree), XCHK_GFP_FLAGS);
+ if (!dl)
+ return -ENOMEM;
+ dl->sc = sc;
+ dl->xname.name = dl->namebuf;
+ INIT_LIST_HEAD(&dl->path_list);
+ dl->root_ino = NULLFSINO;
+
+ mutex_init(&dl->lock);
+
+ descr = xchk_xfile_ino_descr(sc, "dirtree path steps");
+ error = xfarray_create(descr, 0, sizeof(struct xchk_dirpath_step),
+ &dl->path_steps);
+ kfree(descr);
+ if (error)
+ goto out_dl;
+
+ descr = xchk_xfile_ino_descr(sc, "dirtree path names");
+ error = xfblob_create(descr, &dl->path_names);
+ kfree(descr);
+ if (error)
+ goto out_steps;
+
+ error = xchk_setup_inode_contents(sc, 0);
+ if (error)
+ goto out_names;
+
+ sc->buf = dl;
+ sc->buf_cleanup = xchk_dirtree_buf_cleanup;
+ return 0;
+
+out_names:
+ xfblob_destroy(dl->path_names);
+out_steps:
+ xfarray_destroy(dl->path_steps);
+out_dl:
+ mutex_destroy(&dl->lock);
+ kvfree(dl);
+ return error;
+}
+
+/*
+ * Add the parent pointer described by @dl->pptr to the given path as a new
+ * step. Returns -ELNRNG if the path is too deep.
+ */
+STATIC int
+xchk_dirpath_append(
+ struct xchk_dirtree *dl,
+ struct xfs_inode *ip,
+ struct xchk_dirpath *path,
+ const struct xfs_name *name,
+ const struct xfs_parent_rec *pptr)
+{
+ struct xchk_dirpath_step step = {
+ .pptr_rec = *pptr, /* struct copy */
+ .name_len = name->len,
+ };
+ int error;
+
+ /*
+ * If this path is more than 2 billion steps long, this directory tree
+ * is too far gone to fix.
+ */
+ if (path->nr_steps >= XFS_MAXLINK)
+ return -ELNRNG;
+
+ error = xfblob_storename(dl->path_names, &step.name_cookie, name);
+ if (error)
+ return error;
+
+ error = xino_bitmap_set(&path->seen_inodes, ip->i_ino);
+ if (error)
+ return error;
+
+ error = xfarray_append(dl->path_steps, &step);
+ if (error)
+ return error;
+
+ path->nr_steps++;
+ return 0;
+}
+
+/*
+ * Create an xchk_path for each parent pointer of the directory that we're
+ * scanning. For each path created, we will eventually try to walk towards the
+ * root with the goal of deleting all parents except for one that leads to the
+ * root.
+ *
+ * Returns -EFSCORRUPTED to signal that the inode being scanned has a corrupt
+ * parent pointer and hence there's no point in continuing; or -ENOSR if there
+ * are too many parent pointers for this directory.
+ */
+STATIC int
+xchk_dirtree_create_path(
+ struct xfs_scrub *sc,
+ struct xfs_inode *ip,
+ unsigned int attr_flags,
+ const unsigned char *name,
+ unsigned int namelen,
+ const void *value,
+ unsigned int valuelen,
+ void *priv)
+{
+ struct xfs_name xname = {
+ .name = name,
+ .len = namelen,
+ };
+ struct xchk_dirtree *dl = priv;
+ struct xchk_dirpath *path;
+ const struct xfs_parent_rec *rec = value;
+ int error;
+
+ if (!(attr_flags & XFS_ATTR_PARENT))
+ return 0;
+
+ error = xfs_parent_from_attr(sc->mp, attr_flags, name, namelen, value,
+ valuelen, NULL, NULL);
+ if (error)
+ return error;
+
+ /*
+ * If there are more than 2 billion actual parent pointers for this
+ * subdirectory, this fs is too far gone to fix.
+ */
+ if (dl->nr_paths >= XFS_MAXLINK)
+ return -ENOSR;
+
+ trace_xchk_dirtree_create_path(sc, ip, dl->nr_paths, &xname, rec);
+
+ /*
+ * Create a new xchk_path structure to remember this parent pointer
+ * and record the first name step.
+ */
+ path = kmalloc(sizeof(struct xchk_dirpath), XCHK_GFP_FLAGS);
+ if (!path)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&path->list);
+ xino_bitmap_init(&path->seen_inodes);
+ path->nr_steps = 0;
+ path->outcome = XCHK_DIRPATH_SCANNING;
+
+ error = xchk_dirpath_append(dl, sc->ip, path, &xname, rec);
+ if (error)
+ goto out_path;
+
+ path->first_step = xfarray_length(dl->path_steps) - 1;
+ path->second_step = XFARRAY_NULLIDX;
+ path->path_nr = dl->nr_paths;
+
+ list_add_tail(&path->list, &dl->path_list);
+ dl->nr_paths++;
+ return 0;
+out_path:
+ kfree(path);
+ return error;
+}
+
+/*
+ * Validate that the first step of this path still has a corresponding
+ * parent pointer in @sc->ip. We probably dropped @sc->ip's ILOCK while
+ * walking towards the roots, which is why this is necessary.
+ *
+ * This function has a side effect of loading the first parent pointer of this
+ * path into the parent pointer scratch pad. This prepares us to walk up the
+ * directory tree towards the root. Returns -ESTALE if the scan data is now
+ * out of date.
+ */
+STATIC int
+xchk_dirpath_revalidate(
+ struct xchk_dirtree *dl,
+ struct xchk_dirpath *path)
+{
+ struct xfs_scrub *sc = dl->sc;
+ int error;
+
+ /*
+ * Look up the parent pointer that corresponds to the start of this
+ * path. If the parent pointer has disappeared on us, dump all the
+ * scan results and try again.
+ */
+ error = xfs_parent_lookup(sc->tp, sc->ip, &dl->xname, &dl->pptr_rec,
+ &dl->pptr_args);
+ if (error == -ENOATTR) {
+ trace_xchk_dirpath_disappeared(dl->sc, sc->ip, path->path_nr,
+ path->first_step, &dl->xname, &dl->pptr_rec);
+ dl->stale = true;
+ return -ESTALE;
+ }
+
+ return error;
+}
+
+/*
+ * Walk the parent pointers of a directory at the end of a path and record
+ * the parent that we find in @dl->xname/pptr_rec.
+ */
+STATIC int
+xchk_dirpath_find_next_step(
+ struct xfs_scrub *sc,
+ struct xfs_inode *ip,
+ unsigned int attr_flags,
+ const unsigned char *name,
+ unsigned int namelen,
+ const void *value,
+ unsigned int valuelen,
+ void *priv)
+{
+ struct xchk_dirtree *dl = priv;
+ const struct xfs_parent_rec *rec = value;
+ int error;
+
+ if (!(attr_flags & XFS_ATTR_PARENT))
+ return 0;
+
+ error = xfs_parent_from_attr(sc->mp, attr_flags, name, namelen, value,
+ valuelen, NULL, NULL);
+ if (error)
+ return error;
+
+ /*
+ * If we've already set @dl->pptr_rec, then this directory has multiple
+ * parents. Signal this back to the caller via -EMLINK.
+ */
+ if (dl->parents_found > 0)
+ return -EMLINK;
+
+ dl->parents_found++;
+ memcpy(dl->namebuf, name, namelen);
+ dl->xname.len = namelen;
+ dl->pptr_rec = *rec; /* struct copy */
+ return 0;
+}
+
+/* Set and log the outcome of a path walk. */
+static inline void
+xchk_dirpath_set_outcome(
+ struct xchk_dirtree *dl,
+ struct xchk_dirpath *path,
+ enum xchk_dirpath_outcome outcome)
+{
+ trace_xchk_dirpath_set_outcome(dl->sc, path->path_nr, path->nr_steps,
+ outcome);
+
+ path->outcome = outcome;
+}
+
+/*
+ * Scan the directory at the end of this path for its parent directory link.
+ * If we find one, extend the path. Returns -ESTALE if the scan data out of
+ * date. Returns -EFSCORRUPTED if the parent pointer is bad; or -ELNRNG if
+ * the path got too deep.
+ */
+STATIC int
+xchk_dirpath_step_up(
+ struct xchk_dirtree *dl,
+ struct xchk_dirpath *path)
+{
+ struct xfs_scrub *sc = dl->sc;
+ struct xfs_inode *dp;
+ xfs_ino_t parent_ino = be64_to_cpu(dl->pptr_rec.p_ino);
+ unsigned int lock_mode;
+ int error;
+
+ /* Grab and lock the parent directory. */
+ error = xchk_iget(sc, parent_ino, &dp);
+ if (error)
+ return error;
+
+ lock_mode = xfs_ilock_attr_map_shared(dp);
+ mutex_lock(&dl->lock);
+
+ if (dl->stale) {
+ error = -ESTALE;
+ goto out_scanlock;
+ }
+
+ /* We've reached the root directory; the path is ok. */
+ if (parent_ino == dl->root_ino) {
+ xchk_dirpath_set_outcome(dl, path, XCHK_DIRPATH_OK);
+ error = 0;
+ goto out_scanlock;
+ }
+
+ /*
+ * The inode being scanned is its own distant ancestor! Get rid of
+ * this path.
+ */
+ if (parent_ino == sc->ip->i_ino) {
+ xchk_dirpath_set_outcome(dl, path, XCHK_DIRPATH_DELETE);
+ error = 0;
+ goto out_scanlock;
+ }
+
+ /*
+ * We've seen this inode before during the path walk. There's a loop
+ * above us in the directory tree. This probably means that we cannot
+ * continue, but let's keep walking paths to get a full picture.
+ */
+ if (xino_bitmap_test(&path->seen_inodes, parent_ino)) {
+ xchk_dirpath_set_outcome(dl, path, XCHK_DIRPATH_LOOP);
+ error = 0;
+ goto out_scanlock;
+ }
+
+ /* The handle encoded in the parent pointer must match. */
+ if (VFS_I(dp)->i_generation != be32_to_cpu(dl->pptr_rec.p_gen)) {
+ trace_xchk_dirpath_badgen(dl->sc, dp, path->path_nr,
+ path->nr_steps, &dl->xname, &dl->pptr_rec);
+ error = -EFSCORRUPTED;
+ goto out_scanlock;
+ }
+
+ /* Parent pointer must point up to a directory. */
+ if (!S_ISDIR(VFS_I(dp)->i_mode)) {
+ trace_xchk_dirpath_nondir_parent(dl->sc, dp, path->path_nr,
+ path->nr_steps, &dl->xname, &dl->pptr_rec);
+ error = -EFSCORRUPTED;
+ goto out_scanlock;
+ }
+
+ /* Parent cannot be an unlinked directory. */
+ if (VFS_I(dp)->i_nlink == 0) {
+ trace_xchk_dirpath_unlinked_parent(dl->sc, dp, path->path_nr,
+ path->nr_steps, &dl->xname, &dl->pptr_rec);
+ error = -EFSCORRUPTED;
+ goto out_scanlock;
+ }
+
+ /*
+ * If the extended attributes look as though they has been zapped by
+ * the inode record repair code, we cannot scan for parent pointers.
+ */
+ if (xchk_pptr_looks_zapped(dp)) {
+ error = -EBUSY;
+ xchk_set_incomplete(sc);
+ goto out_scanlock;
+ }
+
+ /*
+ * Walk the parent pointers of @dp to find the parent of this directory
+ * to find the next step in our walk. If we find that @dp has exactly
+ * one parent, the parent pointer information will be stored in
+ * @dl->pptr_rec. This prepares us for the next step of the walk.
+ */
+ mutex_unlock(&dl->lock);
+ dl->parents_found = 0;
+ error = xchk_xattr_walk(sc, dp, xchk_dirpath_find_next_step, NULL, dl);
+ mutex_lock(&dl->lock);
+ if (error == -EFSCORRUPTED || error == -EMLINK ||
+ (!error && dl->parents_found == 0)) {
+ /*
+ * Further up the directory tree from @sc->ip, we found a
+ * corrupt parent pointer, multiple parent pointers while
+ * finding this directory's parent, or zero parents despite
+ * having a nonzero link count. Keep looking for other paths.
+ */
+ xchk_dirpath_set_outcome(dl, path, XCHK_DIRPATH_CORRUPT);
+ error = 0;
+ goto out_scanlock;
+ }
+ if (error)
+ goto out_scanlock;
+
+ if (dl->stale) {
+ error = -ESTALE;
+ goto out_scanlock;
+ }
+
+ trace_xchk_dirpath_found_next_step(sc, dp, path->path_nr,
+ path->nr_steps, &dl->xname, &dl->pptr_rec);
+
+ /* Append to the path steps */
+ error = xchk_dirpath_append(dl, dp, path, &dl->xname, &dl->pptr_rec);
+ if (error)
+ goto out_scanlock;
+
+ if (path->second_step == XFARRAY_NULLIDX)
+ path->second_step = xfarray_length(dl->path_steps) - 1;
+
+out_scanlock:
+ mutex_unlock(&dl->lock);
+ xfs_iunlock(dp, lock_mode);
+ xchk_irele(sc, dp);
+ return error;
+}
+
+/*
+ * Walk the directory tree upwards towards what is hopefully the root
+ * directory, recording path steps as we go. The current path components are
+ * stored in dl->pptr_rec and dl->xname.
+ *
+ * Returns -ESTALE if the scan data are out of date. Returns -EFSCORRUPTED
+ * only if the direct parent pointer of @sc->ip associated with this path is
+ * corrupt.
+ */
+STATIC int
+xchk_dirpath_walk_upwards(
+ struct xchk_dirtree *dl,
+ struct xchk_dirpath *path)
+{
+ struct xfs_scrub *sc = dl->sc;
+ int error;
+
+ ASSERT(sc->ilock_flags & XFS_ILOCK_EXCL);
+
+ /* Reload the start of this path and make sure it's still there. */
+ error = xchk_dirpath_revalidate(dl, path);
+ if (error)
+ return error;
+
+ trace_xchk_dirpath_walk_upwards(sc, sc->ip, path->path_nr, &dl->xname,
+ &dl->pptr_rec);
+
+ /*
+ * The inode being scanned is its own direct ancestor!
+ * Get rid of this path.
+ */
+ if (be64_to_cpu(dl->pptr_rec.p_ino) == sc->ip->i_ino) {
+ xchk_dirpath_set_outcome(dl, path, XCHK_DIRPATH_DELETE);
+ return 0;
+ }
+
+ /*
+ * Drop ILOCK_EXCL on the inode being scanned. We still hold
+ * IOLOCK_EXCL on it, so it cannot move around or be renamed.
+ *
+ * Beyond this point we're walking up the directory tree, which means
+ * that we can acquire and drop the ILOCK on an alias of sc->ip. The
+ * ILOCK state is no longer tracked in the scrub context. Hence we
+ * must drop @sc->ip's ILOCK during the walk.
+ */
+ mutex_unlock(&dl->lock);
+ xchk_iunlock(sc, XFS_ILOCK_EXCL);
+
+ /*
+ * Take the first step in the walk towards the root by checking the
+ * start of this path, which is a direct parent pointer of @sc->ip.
+ * If we see any kind of error here (including corruptions), the parent
+ * pointer of @sc->ip is corrupt. Stop the whole scan.
+ */
+ error = xchk_dirpath_step_up(dl, path);
+ if (error) {
+ xchk_ilock(sc, XFS_ILOCK_EXCL);
+ mutex_lock(&dl->lock);
+ return error;
+ }
+
+ /*
+ * Take steps upward from the second step in this path towards the
+ * root. If we hit corruption errors here, there's a problem
+ * *somewhere* in the path, but we don't need to stop scanning.
+ */
+ while (!error && path->outcome == XCHK_DIRPATH_SCANNING)
+ error = xchk_dirpath_step_up(dl, path);
+
+ /* Retake the locks we had, mark paths, etc. */
+ xchk_ilock(sc, XFS_ILOCK_EXCL);
+ mutex_lock(&dl->lock);
+ if (error == -EFSCORRUPTED) {
+ xchk_dirpath_set_outcome(dl, path, XCHK_DIRPATH_CORRUPT);
+ error = 0;
+ }
+ if (!error && dl->stale)
+ return -ESTALE;
+ return error;
+}
+
+/* Delete all the collected path information. */
+STATIC void
+xchk_dirtree_reset(
+ void *buf)
+{
+ struct xchk_dirtree *dl = buf;
+ struct xchk_dirpath *path, *n;
+
+ ASSERT(dl->sc->ilock_flags & XFS_ILOCK_EXCL);
+
+ xchk_dirtree_for_each_path_safe(dl, path, n) {
+ list_del_init(&path->list);
+ xino_bitmap_destroy(&path->seen_inodes);
+ kfree(path);
+ }
+ dl->nr_paths = 0;
+
+ xfarray_truncate(dl->path_steps);
+ xfblob_truncate(dl->path_names);
+
+ dl->stale = false;
+}
+
+/*
+ * Load the name/pptr from the first step in this path into @dl->pptr_rec and
+ * @dl->xname.
+ */
+STATIC int
+xchk_dirtree_load_path(
+ struct xchk_dirtree *dl,
+ struct xchk_dirpath *path)
+{
+ struct xchk_dirpath_step step;
+ int error;
+
+ error = xfarray_load(dl->path_steps, path->first_step, &step);
+ if (error)
+ return error;
+
+ error = xfblob_loadname(dl->path_names, step.name_cookie, &dl->xname,
+ step.name_len);
+ if (error)
+ return error;
+
+ dl->pptr_rec = step.pptr_rec; /* struct copy */
+ return 0;
+}
+
+/*
+ * For each parent pointer of this subdir, trace a path upwards towards the
+ * root directory and record what we find. Returns 0 for success;
+ * -EFSCORRUPTED if walking the parent pointers of @sc->ip failed, -ELNRNG if a
+ * path was too deep; -ENOSR if there were too many parent pointers; or
+ * a negative errno.
+ */
+STATIC int
+xchk_dirtree_find_paths_to_root(
+ struct xchk_dirtree *dl)
+{
+ struct xfs_scrub *sc = dl->sc;
+ struct xchk_dirpath *path;
+ int error = 0;
+
+ do {
+ if (xchk_should_terminate(sc, &error))
+ return error;
+
+ xchk_dirtree_reset(dl);
+
+ /*
+ * If the extended attributes look as though they has been
+ * zapped by the inode record repair code, we cannot scan for
+ * parent pointers.
+ */
+ if (xchk_pptr_looks_zapped(sc->ip)) {
+ xchk_set_incomplete(sc);
+ return -EBUSY;
+ }
+
+ /*
+ * Create path walk contexts for each parent of the directory
+ * that is being scanned. Directories are supposed to have
+ * only one parent, but this is how we detect multiple parents.
+ */
+ error = xchk_xattr_walk(sc, sc->ip, xchk_dirtree_create_path,
+ NULL, dl);
+ if (error)
+ return error;
+
+ xchk_dirtree_for_each_path(dl, path) {
+ /* Load path components into dl->pptr/xname */
+ error = xchk_dirtree_load_path(dl, path);
+ if (error)
+ return error;
+
+ /*
+ * Try to walk up each path to the root. This enables
+ * us to find directory loops in ancestors, and the
+ * like.
+ */
+ error = xchk_dirpath_walk_upwards(dl, path);
+ if (error == -EFSCORRUPTED) {
+ /*
+ * A parent pointer of @sc->ip is bad, don't
+ * bother continuing.
+ */
+ break;
+ }
+ if (error == -ESTALE) {
+ /* This had better be an invalidation. */
+ ASSERT(dl->stale);
+ break;
+ }
+ if (error)
+ return error;
+ }
+ } while (dl->stale);
+
+ return error;
+}
+
+/*
+ * Figure out what to do with the paths we tried to find. Do not call this
+ * if the scan results are stale.
+ */
+STATIC void
+xchk_dirtree_evaluate(
+ struct xchk_dirtree *dl,
+ struct xchk_dirtree_outcomes *oc)
+{
+ struct xchk_dirpath *path;
+
+ ASSERT(!dl->stale);
+
+ /* Scan the paths we have to decide what to do. */
+ memset(oc, 0, sizeof(struct xchk_dirtree_outcomes));
+ xchk_dirtree_for_each_path(dl, path) {
+ trace_xchk_dirpath_evaluate_path(dl->sc, path->path_nr,
+ path->nr_steps, path->outcome);
+
+ switch (path->outcome) {
+ case XCHK_DIRPATH_SCANNING:
+ /* shouldn't get here */
+ ASSERT(0);
+ break;
+ case XCHK_DIRPATH_DELETE:
+ /* This one is already going away. */
+ oc->bad++;
+ break;
+ case XCHK_DIRPATH_CORRUPT:
+ case XCHK_DIRPATH_LOOP:
+ /* Couldn't find the end of this path. */
+ oc->suspect++;
+ break;
+ case XCHK_DIRPATH_STALE:
+ /* shouldn't get here either */
+ ASSERT(0);
+ break;
+ case XCHK_DIRPATH_OK:
+ /* This path got all the way to the root. */
+ oc->good++;
+ break;
+ }
+ }
+
+ trace_xchk_dirtree_evaluate(dl, oc);
+}
+
+/* Look for directory loops. */
+int
+xchk_dirtree(
+ struct xfs_scrub *sc)
+{
+ struct xchk_dirtree_outcomes oc;
+ struct xchk_dirtree *dl = sc->buf;
+ int error;
+
+ /*
+ * Nondirectories do not point downwards to other files, so they cannot
+ * cause a cycle in the directory tree.
+ */
+ if (!S_ISDIR(VFS_I(sc->ip)->i_mode))
+ return -ENOENT;
+
+ ASSERT(xfs_has_parent(sc->mp));
+
+ /* Find the root of the directory tree. */
+ dl->root_ino = sc->mp->m_rootip->i_ino;
+
+ trace_xchk_dirtree_start(sc->ip, sc->sm, 0);
+
+ mutex_lock(&dl->lock);
+
+ /* Trace each parent pointer's path to the root. */
+ error = xchk_dirtree_find_paths_to_root(dl);
+ if (error == -EFSCORRUPTED || error == -ELNRNG || error == -ENOSR) {
+ /*
+ * Don't bother walking the paths if the xattr structure or the
+ * parent pointers are corrupt; this scan cannot be completed
+ * without full information.
+ */
+ xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
+ error = 0;
+ goto out_scanlock;
+ }
+ if (error == -EBUSY) {
+ /*
+ * We couldn't scan some directory's parent pointers because
+ * the attr fork looked like it had been zapped. The
+ * scan was marked incomplete, so no further error code
+ * is necessary.
+ */
+ error = 0;
+ goto out_scanlock;
+ }
+ if (error)
+ goto out_scanlock;
+
+ /* Assess what we found in our path evaluation. */
+ xchk_dirtree_evaluate(dl, &oc);
+ if (xchk_dirtree_parentless(dl)) {
+ if (oc.good || oc.bad || oc.suspect)
+ xchk_ino_set_corrupt(sc, sc->ip->i_ino);
+ } else {
+ if (oc.bad || oc.good + oc.suspect != 1)
+ xchk_ino_set_corrupt(sc, sc->ip->i_ino);
+ if (oc.suspect)
+ xchk_ino_xref_set_corrupt(sc, sc->ip->i_ino);
+ }
+
+out_scanlock:
+ mutex_unlock(&dl->lock);
+ trace_xchk_dirtree_done(sc->ip, sc->sm, error);
+ return error;
+}
struct xchk_fscounters;
struct xfs_rmap_update_params;
struct xfs_parent_rec;
+enum xchk_dirpath_outcome;
+struct xchk_dirtree;
+struct xchk_dirtree_outcomes;
/*
* ftrace's __print_symbolic requires that all enum values be wrapped in the
TRACE_DEFINE_ENUM(XFS_SCRUB_TYPE_QUOTACHECK);
TRACE_DEFINE_ENUM(XFS_SCRUB_TYPE_NLINKS);
TRACE_DEFINE_ENUM(XFS_SCRUB_TYPE_HEALTHY);
+TRACE_DEFINE_ENUM(XFS_SCRUB_TYPE_DIRTREE);
#define XFS_SCRUB_TYPE_STRINGS \
{ XFS_SCRUB_TYPE_PROBE, "probe" }, \
{ XFS_SCRUB_TYPE_FSCOUNTERS, "fscounters" }, \
{ XFS_SCRUB_TYPE_QUOTACHECK, "quotacheck" }, \
{ XFS_SCRUB_TYPE_NLINKS, "nlinks" }, \
- { XFS_SCRUB_TYPE_HEALTHY, "healthy" }
+ { XFS_SCRUB_TYPE_HEALTHY, "healthy" }, \
+ { XFS_SCRUB_TYPE_DIRTREE, "dirtree" }
#define XFS_SCRUB_FLAG_STRINGS \
{ XFS_SCRUB_IFLAG_REPAIR, "repair" }, \
DEFINE_SCRUB_EVENT(xchk_start);
DEFINE_SCRUB_EVENT(xchk_done);
DEFINE_SCRUB_EVENT(xchk_deadlock_retry);
+DEFINE_SCRUB_EVENT(xchk_dirtree_start);
+DEFINE_SCRUB_EVENT(xchk_dirtree_done);
DEFINE_SCRUB_EVENT(xrep_attempt);
DEFINE_SCRUB_EVENT(xrep_done);
DEFINE_XCHK_PPTR_EVENT(xchk_parent_slowpath);
DEFINE_XCHK_PPTR_EVENT(xchk_parent_ultraslowpath);
+DECLARE_EVENT_CLASS(xchk_dirtree_class,
+ TP_PROTO(struct xfs_scrub *sc, struct xfs_inode *ip,
+ unsigned int path_nr, const struct xfs_name *name,
+ const struct xfs_parent_rec *pptr),
+ TP_ARGS(sc, ip, path_nr, name, pptr),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(unsigned int, path_nr)
+ __field(xfs_ino_t, child_ino)
+ __field(unsigned int, child_gen)
+ __field(xfs_ino_t, parent_ino)
+ __field(unsigned int, parent_gen)
+ __field(unsigned int, namelen)
+ __dynamic_array(char, name, name->len)
+ ),
+ TP_fast_assign(
+ __entry->dev = sc->mp->m_super->s_dev;
+ __entry->path_nr = path_nr;
+ __entry->child_ino = ip->i_ino;
+ __entry->child_gen = VFS_I(ip)->i_generation;
+ __entry->parent_ino = be64_to_cpu(pptr->p_ino);
+ __entry->parent_gen = be32_to_cpu(pptr->p_gen);
+ __entry->namelen = name->len;
+ memcpy(__get_str(name), name->name, name->len);
+ ),
+ TP_printk("dev %d:%d path %u child_ino 0x%llx child_gen 0x%x parent_ino 0x%llx parent_gen 0x%x name '%.*s'",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->path_nr,
+ __entry->child_ino,
+ __entry->child_gen,
+ __entry->parent_ino,
+ __entry->parent_gen,
+ __entry->namelen,
+ __get_str(name))
+);
+#define DEFINE_XCHK_DIRTREE_EVENT(name) \
+DEFINE_EVENT(xchk_dirtree_class, name, \
+ TP_PROTO(struct xfs_scrub *sc, struct xfs_inode *ip, \
+ unsigned int path_nr, const struct xfs_name *name, \
+ const struct xfs_parent_rec *pptr), \
+ TP_ARGS(sc, ip, path_nr, name, pptr))
+DEFINE_XCHK_DIRTREE_EVENT(xchk_dirtree_create_path);
+DEFINE_XCHK_DIRTREE_EVENT(xchk_dirpath_walk_upwards);
+
+DECLARE_EVENT_CLASS(xchk_dirpath_class,
+ TP_PROTO(struct xfs_scrub *sc, struct xfs_inode *ip,
+ unsigned int path_nr, unsigned int step_nr,
+ const struct xfs_name *name,
+ const struct xfs_parent_rec *pptr),
+ TP_ARGS(sc, ip, path_nr, step_nr, name, pptr),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(unsigned int, path_nr)
+ __field(unsigned int, step_nr)
+ __field(xfs_ino_t, child_ino)
+ __field(unsigned int, child_gen)
+ __field(xfs_ino_t, parent_ino)
+ __field(unsigned int, parent_gen)
+ __field(unsigned int, namelen)
+ __dynamic_array(char, name, name->len)
+ ),
+ TP_fast_assign(
+ __entry->dev = sc->mp->m_super->s_dev;
+ __entry->path_nr = path_nr;
+ __entry->step_nr = step_nr;
+ __entry->child_ino = ip->i_ino;
+ __entry->child_gen = VFS_I(ip)->i_generation;
+ __entry->parent_ino = be64_to_cpu(pptr->p_ino);
+ __entry->parent_gen = be32_to_cpu(pptr->p_gen);
+ __entry->namelen = name->len;
+ memcpy(__get_str(name), name->name, name->len);
+ ),
+ TP_printk("dev %d:%d path %u step %u child_ino 0x%llx child_gen 0x%x parent_ino 0x%llx parent_gen 0x%x name '%.*s'",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->path_nr,
+ __entry->step_nr,
+ __entry->child_ino,
+ __entry->child_gen,
+ __entry->parent_ino,
+ __entry->parent_gen,
+ __entry->namelen,
+ __get_str(name))
+);
+#define DEFINE_XCHK_DIRPATH_EVENT(name) \
+DEFINE_EVENT(xchk_dirpath_class, name, \
+ TP_PROTO(struct xfs_scrub *sc, struct xfs_inode *ip, \
+ unsigned int path_nr, unsigned int step_nr, \
+ const struct xfs_name *name, \
+ const struct xfs_parent_rec *pptr), \
+ TP_ARGS(sc, ip, path_nr, step_nr, name, pptr))
+DEFINE_XCHK_DIRPATH_EVENT(xchk_dirpath_disappeared);
+DEFINE_XCHK_DIRPATH_EVENT(xchk_dirpath_badgen);
+DEFINE_XCHK_DIRPATH_EVENT(xchk_dirpath_nondir_parent);
+DEFINE_XCHK_DIRPATH_EVENT(xchk_dirpath_unlinked_parent);
+DEFINE_XCHK_DIRPATH_EVENT(xchk_dirpath_found_next_step);
+
+TRACE_DEFINE_ENUM(XCHK_DIRPATH_SCANNING);
+TRACE_DEFINE_ENUM(XCHK_DIRPATH_DELETE);
+TRACE_DEFINE_ENUM(XCHK_DIRPATH_CORRUPT);
+TRACE_DEFINE_ENUM(XCHK_DIRPATH_LOOP);
+TRACE_DEFINE_ENUM(XCHK_DIRPATH_STALE);
+TRACE_DEFINE_ENUM(XCHK_DIRPATH_OK);
+
+#define XCHK_DIRPATH_OUTCOME_STRINGS \
+ { XCHK_DIRPATH_SCANNING, "scanning" }, \
+ { XCHK_DIRPATH_DELETE, "delete" }, \
+ { XCHK_DIRPATH_CORRUPT, "corrupt" }, \
+ { XCHK_DIRPATH_LOOP, "loop" }, \
+ { XCHK_DIRPATH_STALE, "stale" }, \
+ { XCHK_DIRPATH_OK, "ok" }
+
+DECLARE_EVENT_CLASS(xchk_dirpath_outcome_class,
+ TP_PROTO(struct xfs_scrub *sc, unsigned long long path_nr,
+ unsigned int nr_steps, \
+ unsigned int outcome),
+ TP_ARGS(sc, path_nr, nr_steps, outcome),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(unsigned long long, path_nr)
+ __field(unsigned int, nr_steps)
+ __field(unsigned int, outcome)
+ ),
+ TP_fast_assign(
+ __entry->dev = sc->mp->m_super->s_dev;
+ __entry->path_nr = path_nr;
+ __entry->nr_steps = nr_steps;
+ __entry->outcome = outcome;
+ ),
+ TP_printk("dev %d:%d path %llu steps %u outcome %s",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->path_nr,
+ __entry->nr_steps,
+ __print_symbolic(__entry->outcome, XCHK_DIRPATH_OUTCOME_STRINGS))
+);
+#define DEFINE_XCHK_DIRPATH_OUTCOME_EVENT(name) \
+DEFINE_EVENT(xchk_dirpath_outcome_class, name, \
+ TP_PROTO(struct xfs_scrub *sc, unsigned long long path_nr, \
+ unsigned int nr_steps, \
+ unsigned int outcome), \
+ TP_ARGS(sc, path_nr, nr_steps, outcome))
+DEFINE_XCHK_DIRPATH_OUTCOME_EVENT(xchk_dirpath_set_outcome);
+DEFINE_XCHK_DIRPATH_OUTCOME_EVENT(xchk_dirpath_evaluate_path);
+
+DECLARE_EVENT_CLASS(xchk_dirtree_evaluate_class,
+ TP_PROTO(const struct xchk_dirtree *dl,
+ const struct xchk_dirtree_outcomes *oc),
+ TP_ARGS(dl, oc),
+ TP_STRUCT__entry(
+ __field(dev_t, dev)
+ __field(xfs_ino_t, ino)
+ __field(xfs_ino_t, rootino)
+ __field(unsigned int, nr_paths)
+ __field(unsigned int, bad)
+ __field(unsigned int, suspect)
+ __field(unsigned int, good)
+ ),
+ TP_fast_assign(
+ __entry->dev = dl->sc->mp->m_super->s_dev;
+ __entry->ino = dl->sc->ip->i_ino;
+ __entry->rootino = dl->root_ino;
+ __entry->nr_paths = dl->nr_paths;
+ __entry->bad = oc->bad;
+ __entry->suspect = oc->suspect;
+ __entry->good = oc->good;
+ ),
+ TP_printk("dev %d:%d ino 0x%llx rootino 0x%llx nr_paths %u bad %u suspect %u good %u",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ __entry->ino,
+ __entry->rootino,
+ __entry->nr_paths,
+ __entry->bad,
+ __entry->suspect,
+ __entry->good)
+);
+#define DEFINE_XCHK_DIRTREE_EVALUATE_EVENT(name) \
+DEFINE_EVENT(xchk_dirtree_evaluate_class, name, \
+ TP_PROTO(const struct xchk_dirtree *dl, \
+ const struct xchk_dirtree_outcomes *oc), \
+ TP_ARGS(dl, oc))
+DEFINE_XCHK_DIRTREE_EVALUATE_EVENT(xchk_dirtree_evaluate);
+
/* repair tracepoints */
#if IS_ENABLED(CONFIG_XFS_ONLINE_REPAIR)
projects / linux-2.6-block.git / commitdiff