linux/fs/xfs/libxfs/xfs_trans_inode.c
Darrick J. Wong 83193e5ebb xfs: correct the narrative around misaligned rtinherit/extszinherit dirs
While auditing the realtime growfs code, I realized that the GROWFSRT
ioctl (and by extension xfs_growfs) has always allowed sysadmins to
change the realtime extent size when adding a realtime section to the
filesystem.  Since we also have always allowed sysadmins to set
RTINHERIT and EXTSZINHERIT on directories even if there is no realtime
device, this invalidates the premise laid out in the comments added in
commit 603f000b15.

In other words, this is not a case of inadequate metadata validation.
This is a case of nearly forgotten (and apparently untested) but
supported functionality.  Update the comments to reflect what we've
learned, and remove the log message about correcting the misalignment.

Fixes: 603f000b15 ("xfs: validate extsz hints against rt extent size when rtinherit is set")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2021-07-15 09:58:42 -07:00

226 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_inode_item.h"
#include <linux/iversion.h>
/*
* Add a locked inode to the transaction.
*
* The inode must be locked, and it cannot be associated with any transaction.
* If lock_flags is non-zero the inode will be unlocked on transaction commit.
*/
void
xfs_trans_ijoin(
struct xfs_trans *tp,
struct xfs_inode *ip,
uint lock_flags)
{
struct xfs_inode_log_item *iip;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
if (ip->i_itemp == NULL)
xfs_inode_item_init(ip, ip->i_mount);
iip = ip->i_itemp;
ASSERT(iip->ili_lock_flags == 0);
iip->ili_lock_flags = lock_flags;
ASSERT(!xfs_iflags_test(ip, XFS_ISTALE));
/*
* Get a log_item_desc to point at the new item.
*/
xfs_trans_add_item(tp, &iip->ili_item);
}
/*
* Transactional inode timestamp update. Requires the inode to be locked and
* joined to the transaction supplied. Relies on the transaction subsystem to
* track dirty state and update/writeback the inode accordingly.
*/
void
xfs_trans_ichgtime(
struct xfs_trans *tp,
struct xfs_inode *ip,
int flags)
{
struct inode *inode = VFS_I(ip);
struct timespec64 tv;
ASSERT(tp);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
tv = current_time(inode);
if (flags & XFS_ICHGTIME_MOD)
inode->i_mtime = tv;
if (flags & XFS_ICHGTIME_CHG)
inode->i_ctime = tv;
if (flags & XFS_ICHGTIME_CREATE)
ip->i_crtime = tv;
}
/*
* This is called to mark the fields indicated in fieldmask as needing to be
* logged when the transaction is committed. The inode must already be
* associated with the given transaction.
*
* The values for fieldmask are defined in xfs_inode_item.h. We always log all
* of the core inode if any of it has changed, and we always log all of the
* inline data/extents/b-tree root if any of them has changed.
*
* Grab and pin the cluster buffer associated with this inode to avoid RMW
* cycles at inode writeback time. Avoid the need to add error handling to every
* xfs_trans_log_inode() call by shutting down on read error. This will cause
* transactions to fail and everything to error out, just like if we return a
* read error in a dirty transaction and cancel it.
*/
void
xfs_trans_log_inode(
struct xfs_trans *tp,
struct xfs_inode *ip,
uint flags)
{
struct xfs_inode_log_item *iip = ip->i_itemp;
struct inode *inode = VFS_I(ip);
uint iversion_flags = 0;
ASSERT(iip);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(!xfs_iflags_test(ip, XFS_ISTALE));
tp->t_flags |= XFS_TRANS_DIRTY;
/*
* Don't bother with i_lock for the I_DIRTY_TIME check here, as races
* don't matter - we either will need an extra transaction in 24 hours
* to log the timestamps, or will clear already cleared fields in the
* worst case.
*/
if (inode->i_state & I_DIRTY_TIME) {
spin_lock(&inode->i_lock);
inode->i_state &= ~I_DIRTY_TIME;
spin_unlock(&inode->i_lock);
}
/*
* First time we log the inode in a transaction, bump the inode change
* counter if it is configured for this to occur. While we have the
* inode locked exclusively for metadata modification, we can usually
* avoid setting XFS_ILOG_CORE if no one has queried the value since
* the last time it was incremented. If we have XFS_ILOG_CORE already
* set however, then go ahead and bump the i_version counter
* unconditionally.
*/
if (!test_and_set_bit(XFS_LI_DIRTY, &iip->ili_item.li_flags)) {
if (IS_I_VERSION(inode) &&
inode_maybe_inc_iversion(inode, flags & XFS_ILOG_CORE))
iversion_flags = XFS_ILOG_CORE;
}
/*
* If we're updating the inode core or the timestamps and it's possible
* to upgrade this inode to bigtime format, do so now.
*/
if ((flags & (XFS_ILOG_CORE | XFS_ILOG_TIMESTAMP)) &&
xfs_sb_version_hasbigtime(&ip->i_mount->m_sb) &&
!xfs_inode_has_bigtime(ip)) {
ip->i_diflags2 |= XFS_DIFLAG2_BIGTIME;
flags |= XFS_ILOG_CORE;
}
/*
* Inode verifiers do not check that the extent size hint is an integer
* multiple of the rt extent size on a directory with both rtinherit
* and extszinherit flags set. If we're logging a directory that is
* misconfigured in this way, clear the hint.
*/
if ((ip->i_diflags & XFS_DIFLAG_RTINHERIT) &&
(ip->i_diflags & XFS_DIFLAG_EXTSZINHERIT) &&
(ip->i_extsize % ip->i_mount->m_sb.sb_rextsize) > 0) {
ip->i_diflags &= ~(XFS_DIFLAG_EXTSIZE |
XFS_DIFLAG_EXTSZINHERIT);
ip->i_extsize = 0;
flags |= XFS_ILOG_CORE;
}
/*
* Record the specific change for fdatasync optimisation. This allows
* fdatasync to skip log forces for inodes that are only timestamp
* dirty.
*/
spin_lock(&iip->ili_lock);
iip->ili_fsync_fields |= flags;
if (!iip->ili_item.li_buf) {
struct xfs_buf *bp;
int error;
/*
* We hold the ILOCK here, so this inode is not going to be
* flushed while we are here. Further, because there is no
* buffer attached to the item, we know that there is no IO in
* progress, so nothing will clear the ili_fields while we read
* in the buffer. Hence we can safely drop the spin lock and
* read the buffer knowing that the state will not change from
* here.
*/
spin_unlock(&iip->ili_lock);
error = xfs_imap_to_bp(ip->i_mount, tp, &ip->i_imap, &bp);
if (error) {
xfs_force_shutdown(ip->i_mount, SHUTDOWN_META_IO_ERROR);
return;
}
/*
* We need an explicit buffer reference for the log item but
* don't want the buffer to remain attached to the transaction.
* Hold the buffer but release the transaction reference once
* we've attached the inode log item to the buffer log item
* list.
*/
xfs_buf_hold(bp);
spin_lock(&iip->ili_lock);
iip->ili_item.li_buf = bp;
bp->b_flags |= _XBF_INODES;
list_add_tail(&iip->ili_item.li_bio_list, &bp->b_li_list);
xfs_trans_brelse(tp, bp);
}
/*
* Always OR in the bits from the ili_last_fields field. This is to
* coordinate with the xfs_iflush() and xfs_buf_inode_iodone() routines
* in the eventual clearing of the ili_fields bits. See the big comment
* in xfs_iflush() for an explanation of this coordination mechanism.
*/
iip->ili_fields |= (flags | iip->ili_last_fields | iversion_flags);
spin_unlock(&iip->ili_lock);
}
int
xfs_trans_roll_inode(
struct xfs_trans **tpp,
struct xfs_inode *ip)
{
int error;
xfs_trans_log_inode(*tpp, ip, XFS_ILOG_CORE);
error = xfs_trans_roll(tpp);
if (!error)
xfs_trans_ijoin(*tpp, ip, 0);
return error;
}