path: root/fs/xfs/xfs_trans_dquot.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000-2002 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_quota.h"
#include "xfs_qm.h"
#include "xfs_trace.h"
#include "xfs_error.h"
#include "xfs_health.h"

STATIC void	xfs_trans_alloc_dqinfo(xfs_trans_t *);

/*
 * Add the locked dquot to the transaction.
 * The dquot must be locked, and it cannot be associated with any
 * transaction.
 */
void
xfs_trans_dqjoin(
	struct xfs_trans	*tp,
	struct xfs_dquot	*dqp)
{
	ASSERT(XFS_DQ_IS_LOCKED(dqp));
	ASSERT(dqp->q_logitem.qli_dquot == dqp);

	/*
	 * Get a log_item_desc to point at the new item.
	 */
	xfs_trans_add_item(tp, &dqp->q_logitem.qli_item);
}

/*
 * This is called to mark the dquot as needing
 * to be logged when the transaction is committed.  The dquot must
 * already be associated with the given transaction.
 * Note that it marks the entire transaction as dirty. In the ordinary
 * case, this gets called via xfs_trans_commit, after the transaction
 * is already dirty. However, there's nothing stop this from getting
 * called directly, as done by xfs_qm_scall_setqlim. Hence, the TRANS_DIRTY
 * flag.
 */
void
xfs_trans_log_dquot(
	struct xfs_trans	*tp,
	struct xfs_dquot	*dqp)
{
	ASSERT(XFS_DQ_IS_LOCKED(dqp));

	/* Upgrade the dquot to bigtime format if possible. */
	if (dqp->q_id != 0 &&
	    xfs_has_bigtime(tp->t_mountp) &&
	    !(dqp->q_type & XFS_DQTYPE_BIGTIME))
		dqp->q_type |= XFS_DQTYPE_BIGTIME;

	tp->t_flags |= XFS_TRANS_DIRTY;
	set_bit(XFS_LI_DIRTY, &dqp->q_logitem.qli_item.li_flags);
}

/*
 * Carry forward whatever is left of the quota blk reservation to
 * the spanky new transaction
 */
void
xfs_trans_dup_dqinfo(
	struct xfs_trans	*otp,
	struct xfs_trans	*ntp)
{
	struct xfs_dqtrx	*oq, *nq;
	int			i, j;
	struct xfs_dqtrx	*oqa, *nqa;
	uint64_t		blk_res_used;

	if (!otp->t_dqinfo)
		return;

	xfs_trans_alloc_dqinfo(ntp);

	for (j = 0; j < XFS_QM_TRANS_DQTYPES; j++) {
		oqa = otp->t_dqinfo->dqs[j];
		nqa = ntp->t_dqinfo->dqs[j];
		for (i = 0; i < XFS_QM_TRANS_MAXDQS; i++) {
			blk_res_used = 0;

			if (oqa[i].qt_dquot == NULL)
				break;
			oq = &oqa[i];
			nq = &nqa[i];

			if (oq->qt_blk_res && oq->qt_bcount_delta > 0)
				blk_res_used = oq->qt_bcount_delta;

			nq->qt_dquot = oq->qt_dquot;
			nq->qt_bcount_delta = nq->qt_icount_delta = 0;
			nq->qt_rtbcount_delta = 0;

			/*
			 * Transfer whatever is left of the reservations.
			 */
			nq->qt_blk_res = oq->qt_blk_res - blk_res_used;
			oq->qt_blk_res = blk_res_used;

			nq->qt_rtblk_res = oq->qt_rtblk_res -
				oq->qt_rtblk_res_used;
			oq->qt_rtblk_res = oq->qt_rtblk_res_used;

			nq->qt_ino_res = oq->qt_ino_res - oq->qt_ino_res_used;
			oq->qt_ino_res = oq->qt_ino_res_used;

		}
	}
}

#ifdef CONFIG_XFS_LIVE_HOOKS
/*
 * Use a static key here to reduce the overhead of quota live updates.  If the
 * compiler supports jump labels, the static branch will be replaced by a nop
 * sled when there are no hook users.  Online fsck is currently the only
 * caller, so this is a reasonable tradeoff.
 *
 * Note: Patching the kernel code requires taking the cpu hotplug lock.  Other
 * parts of the kernel allocate memory with that lock held, which means that
 * XFS callers cannot hold any locks that might be used by memory reclaim or
 * writeback when calling the static_branch_{inc,dec} functions.
 */
DEFINE_STATIC_XFS_HOOK_SWITCH(xfs_dqtrx_hooks_switch);

void
xfs_dqtrx_hook_disable(void)
{
	xfs_hooks_switch_off(&xfs_dqtrx_hooks_switch);
}

void
xfs_dqtrx_hook_enable(void)
{
	xfs_hooks_switch_on(&xfs_dqtrx_hooks_switch);
}

/* Schedule a transactional dquot update on behalf of an inode. */
void
xfs_trans_mod_ino_dquot(
	struct xfs_trans		*tp,
	struct xfs_inode		*ip,
	struct xfs_dquot		*dqp,
	unsigned int			field,
	int64_t				delta)
{
	if (xfs_is_metadir_inode(ip))
		return;

	xfs_trans_mod_dquot(tp, dqp, field, delta);

	if (xfs_hooks_switched_on(&xfs_dqtrx_hooks_switch)) {
		struct xfs_mod_ino_dqtrx_params	p = {
			.tx_id		= (uintptr_t)tp,
			.ino		= ip->i_ino,
			.q_type		= xfs_dquot_type(dqp),
			.q_id		= dqp->q_id,
			.delta		= delta
		};
		struct xfs_quotainfo	*qi = tp->t_mountp->m_quotainfo;

		xfs_hooks_call(&qi->qi_mod_ino_dqtrx_hooks, field, &p);
	}
}

/* Call the specified functions during a dquot counter update. */
int
xfs_dqtrx_hook_add(
	struct xfs_quotainfo	*qi,
	struct xfs_dqtrx_hook	*hook)
{
	int			error;

	/*
	 * Transactional dquot updates first call the mod hook when changes
	 * are attached to the transaction and then call the apply hook when
	 * those changes are committed (or canceled).
	 *
	 * The apply hook must be installed before the mod hook so that we
	 * never fail to catch the end of a quota update sequence.
	 */
	error = xfs_hooks_add(&qi->qi_apply_dqtrx_hooks, &hook->apply_hook);
	if (error)
		goto out;

	error = xfs_hooks_add(&qi->qi_mod_ino_dqtrx_hooks, &hook->mod_hook);
	if (error