Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Copyright (C) 2017 Oracle.  All Rights Reserved.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  * Author: Darrick J. Wong <darrick.wong@oracle.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) #include "xfs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) #include "xfs_fs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include "xfs_shared.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include "xfs_format.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include "xfs_trans_resv.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include "xfs_mount.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include "xfs_log_format.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include "xfs_inode.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include "xfs_icache.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include "xfs_dir2.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include "xfs_dir2_priv.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include "scrub/scrub.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include "scrub/common.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) /* Set us up to scrub parents. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) xchk_setup_parent(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	struct xfs_scrub	*sc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 	struct xfs_inode	*ip)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	return xchk_setup_inode_contents(sc, ip, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) /* Parent pointers */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) /* Look for an entry in a parent pointing to this inode. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) struct xchk_parent_ctx {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	struct dir_context	dc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 	struct xfs_scrub	*sc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	xfs_ino_t		ino;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 	xfs_nlink_t		nlink;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	bool			cancelled;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) /* Look for a single entry in a directory pointing to an inode. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) STATIC int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) xchk_parent_actor(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	struct dir_context	*dc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	const char		*name,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	int			namelen,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	loff_t			pos,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	u64			ino,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	unsigned		type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	struct xchk_parent_ctx	*spc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	int			error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	spc = container_of(dc, struct xchk_parent_ctx, dc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 	if (spc->ino == ino)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 		spc->nlink++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	 * If we're facing a fatal signal, bail out.  Store the cancellation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	 * status separately because the VFS readdir code squashes error codes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	 * into short directory reads.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 	if (xchk_should_terminate(spc->sc, &error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 		spc->cancelled = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) /* Count the number of dentries in the parent dir that point to this inode. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) STATIC int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) xchk_parent_count_parent_dentries(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	struct xfs_scrub	*sc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 	struct xfs_inode	*parent,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	xfs_nlink_t		*nlink)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 	struct xchk_parent_ctx	spc = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 		.dc.actor	= xchk_parent_actor,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		.ino		= sc->ip->i_ino,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 		.sc		= sc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	size_t			bufsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	loff_t			oldpos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	uint			lock_mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 	int			error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	 * If there are any blocks, read-ahead block 0 as we're almost
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	 * certain to have the next operation be a read there.  This is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	 * how we guarantee that the parent's extent map has been loaded,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 	 * if there is one.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	lock_mode = xfs_ilock_data_map_shared(parent);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	if (parent->i_df.if_nextents > 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 		error = xfs_dir3_data_readahead(parent, 0, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	xfs_iunlock(parent, lock_mode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 		return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	 * Iterate the parent dir to confirm that there is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	 * exactly one entry pointing back to the inode being
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	 * scanned.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	bufsize = (size_t)min_t(loff_t, XFS_READDIR_BUFSIZE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 			parent->i_d.di_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	oldpos = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	while (true) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 		error = xfs_readdir(sc->tp, parent, &spc.dc, bufsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 		if (spc.cancelled) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 			error = -EAGAIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 		if (oldpos == spc.dc.pos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 		oldpos = spc.dc.pos;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	*nlink = spc.nlink;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)  * Given the inode number of the alleged parent of the inode being
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)  * scrubbed, try to validate that the parent has exactly one directory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)  * entry pointing back to the inode being scrubbed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) STATIC int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) xchk_parent_validate(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	struct xfs_scrub	*sc,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	xfs_ino_t		dnum,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	bool			*try_again)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	struct xfs_mount	*mp = sc->mp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	struct xfs_inode	*dp = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 	xfs_nlink_t		expected_nlink;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 	xfs_nlink_t		nlink;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	int			error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	*try_again = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	/* '..' must not point to ourselves. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	if (sc->ip->i_ino == dnum) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 	 * If we're an unlinked directory, the parent /won't/ have a link
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 	 * to us.  Otherwise, it should have one link.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	expected_nlink = VFS_I(sc->ip)->i_nlink == 0 ? 0 : 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	 * Grab this parent inode.  We release the inode before we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	 * cancel the scrub transaction.  Since we're don't know a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	 * priori that releasing the inode won't trigger eofblocks
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	 * cleanup (which allocates what would be a nested transaction)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	 * if the parent pointer erroneously points to a file, we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	 * can't use DONTCACHE here because DONTCACHE inodes can trigger
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	 * immediate inactive cleanup of the inode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	 * If _iget returns -EINVAL then the parent inode number is garbage
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	 * and the directory is corrupt.  If the _iget returns -EFSCORRUPTED
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	 * or -EFSBADCRC then the parent is corrupt which is a cross
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 	 * referencing error.  Any other error is an operational error.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 	error = xfs_iget(mp, sc->tp, dnum, XFS_IGET_UNTRUSTED, 0, &dp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 	if (error == -EINVAL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 		error = -EFSCORRUPTED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0, &error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	if (dp == sc->ip || !S_ISDIR(VFS_I(dp)->i_mode)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 		goto out_rele;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 	 * We prefer to keep the inode locked while we lock and search
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 	 * its alleged parent for a forward reference.  If we can grab
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 	 * the iolock, validate the pointers and we're done.  We must
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 	 * use nowait here to avoid an ABBA deadlock on the parent and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	 * the child inodes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	if (xfs_ilock_nowait(dp, XFS_IOLOCK_SHARED)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 		error = xchk_parent_count_parent_dentries(sc, dp, &nlink);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 		if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 				&error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 			goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 		if (nlink != expected_nlink)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 			xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 		goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 	 * The game changes if we get here.  We failed to lock the parent,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 	 * so we're going to try to verify both pointers while only holding
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 	 * one lock so as to avoid deadlocking with something that's actually
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 	 * trying to traverse down the directory tree.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 	xfs_iunlock(sc->ip, sc->ilock_flags);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 	sc->ilock_flags = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 	error = xchk_ilock_inverted(dp, XFS_IOLOCK_SHARED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 	if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 		goto out_rele;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 	/* Go looking for our dentry. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 	error = xchk_parent_count_parent_dentries(sc, dp, &nlink);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	if (!xchk_fblock_xref_process_error(sc, XFS_DATA_FORK, 0, &error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 		goto out_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 	/* Drop the parent lock, relock this inode. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 	xfs_iunlock(dp, XFS_IOLOCK_SHARED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 	error = xchk_ilock_inverted(sc->ip, XFS_IOLOCK_EXCL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 	if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 		goto out_rele;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 	sc->ilock_flags = XFS_IOLOCK_EXCL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 	 * If we're an unlinked directory, the parent /won't/ have a link
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 	 * to us.  Otherwise, it should have one link.  We have to re-set
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 	 * it here because we dropped the lock on sc->ip.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 	expected_nlink = VFS_I(sc->ip)->i_nlink == 0 ? 0 : 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 	/* Look up '..' to see if the inode changed. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 	error = xfs_dir_lookup(sc->tp, sc->ip, &xfs_name_dotdot, &dnum, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 		goto out_rele;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 	/* Drat, parent changed.  Try again! */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 	if (dnum != dp->i_ino) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 		xfs_irele(dp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 		*try_again = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 	xfs_irele(dp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 	 * '..' didn't change, so check that there was only one entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 	 * for us in the parent.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 	if (nlink != expected_nlink)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 	return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) out_unlock:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) 	xfs_iunlock(dp, XFS_IOLOCK_SHARED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) out_rele:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) 	xfs_irele(dp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) 	return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) /* Scrub a parent pointer. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) xchk_parent(
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 	struct xfs_scrub	*sc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 	struct xfs_mount	*mp = sc->mp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 	xfs_ino_t		dnum;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 	bool			try_again;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 	int			tries = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 	int			error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 	 * If we're a directory, check that the '..' link points up to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 	 * a directory that has one entry pointing to us.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 	if (!S_ISDIR(VFS_I(sc->ip)->i_mode))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 		return -ENOENT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 	/* We're not a special inode, are we? */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) 	if (!xfs_verify_dir_ino(mp, sc->ip->i_ino)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 	 * The VFS grabs a read or write lock via i_rwsem before it reads
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 	 * or writes to a directory.  If we've gotten this far we've
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 	 * already obtained IOLOCK_EXCL, which (since 4.10) is the same as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 	 * getting a write lock on i_rwsem.  Therefore, it is safe for us
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 	 * to drop the ILOCK here in order to do directory lookups.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 	sc->ilock_flags &= ~(XFS_ILOCK_EXCL | XFS_MMAPLOCK_EXCL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 	xfs_iunlock(sc->ip, XFS_ILOCK_EXCL | XFS_MMAPLOCK_EXCL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) 	/* Look up '..' */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) 	error = xfs_dir_lookup(sc->tp, sc->ip, &xfs_name_dotdot, &dnum, NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) 	if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) 	if (!xfs_verify_dir_ino(mp, dnum)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 	/* Is this the root dir?  Then '..' must point to itself. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 	if (sc->ip == mp->m_rootip) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) 		if (sc->ip->i_ino != mp->m_sb.sb_rootino ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 		    sc->ip->i_ino != dnum)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) 			xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 	do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 		error = xchk_parent_validate(sc, dnum, &try_again);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) 		if (error)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) 	} while (try_again && ++tries < 20);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) 	 * We gave it our best shot but failed, so mark this scrub
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 	 * incomplete.  Userspace can decide if it wants to try again.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 	if (try_again && tries == 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 		xchk_set_incomplete(sc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 	/*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 	 * If we failed to lock the parent inode even after a retry, just mark
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) 	 * this scrub incomplete and return.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) 	if ((sc->flags & XCHK_TRY_HARDER) && error == -EDEADLOCK) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 		error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) 		xchk_set_incomplete(sc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) 	return error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) }