path: root/fs/xfs/xfs_bmap_item.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2016 Oracle.  All Rights Reserved.
 * Author: Darrick J. Wong <darrick.wong@oracle.com>
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_bit.h"
#include "xfs_shared.h"
#include "xfs_mount.h"
#include "xfs_defer.h"
#include "xfs_inode.h"
#include "xfs_trans.h"
#include "xfs_trans_priv.h"
#include "xfs_bmap_item.h"
#include "xfs_log.h"
#include "xfs_bmap.h"
#include "xfs_icache.h"
#include "xfs_bmap_btree.h"
#include "xfs_trans_space.h"
#include "xfs_error.h"
#include "xfs_log_priv.h"
#include "xfs_log_recover.h"
#include "xfs_quota.h"

kmem_zone_t	*xfs_bui_zone;
kmem_zone_t	*xfs_bud_zone;

static const struct xfs_item_ops xfs_bui_item_ops;

static inline struct xfs_bui_log_item *BUI_ITEM(struct xfs_log_item *lip)
{
	return container_of(lip, struct xfs_bui_log_item, bui_item);
}

STATIC void
xfs_bui_item_free(
	struct xfs_bui_log_item	*buip)
{
	kmem_cache_free(xfs_bui_zone, buip);
}

/*
 * Freeing the BUI requires that we remove it from the AIL if it has already
 * been placed there. However, the BUI may not yet have been placed in the AIL
 * when called by xfs_bui_release() from BUD processing due to the ordering of
 * committed vs unpin operations in bulk insert operations. Hence the reference
 * count to ensure only the last caller frees the BUI.
 */
STATIC void
xfs_bui_release(
	struct xfs_bui_log_item	*buip)
{
	ASSERT(atomic_read(&buip->bui_refcount) > 0);
	if (atomic_dec_and_test(&buip->bui_refcount)) {
		xfs_trans_ail_delete(&buip->bui_item, SHUTDOWN_LOG_IO_ERROR);
		xfs_bui_item_free(buip);
	}
}


STATIC void
xfs_bui_item_size(
	struct xfs_log_item	*lip,
	int			*nvecs,
	int			*nbytes)
{
	struct xfs_bui_log_item	*buip = BUI_ITEM(lip);

	*nvecs += 1;
	*nbytes += xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents);
}

/*
 * This is called to fill in the vector of log iovecs for the
 * given bui log item. We use only 1 iovec, and we point that
 * at the bui_log_format structure embedded in the bui item.
 * It is at this point that we assert that all of the extent
 * slots in the bui item have been filled.
 */
STATIC void
xfs_bui_item_format(
	struct xfs_log_item	*lip,
	struct xfs_log_vec	*lv)
{
	struct xfs_bui_log_item	*buip = BUI_ITEM(lip);
	struct xfs_log_iovec	*vecp = NULL;

	ASSERT(atomic_read(&buip->bui_next_extent) ==
			buip->bui_format.bui_nextents);

	buip->bui_format.bui_type = XFS_LI_BUI;
	buip->bui_format.bui_size = 1;

	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUI_FORMAT, &buip->bui_format,
			xfs_bui_log_format_sizeof(buip->bui_format.bui_nextents));
}

/*
 * The unpin operation is the last place an BUI is manipulated in the log. It is
 * either inserted in the AIL or aborted in the event of a log I/O error. In
 * either case, the BUI transaction has been successfully committed to make it
 * this far. Therefore, we expect whoever committed the BUI to either construct
 * and commit the BUD or drop the BUD's reference in the event of error. Simply
 * drop the log's BUI reference now that the log is done with it.
 */
STATIC void
xfs_bui_item_unpin(
	struct xfs_log_item	*lip,
	int			remove)
{
	struct xfs_bui_log_item	*buip = BUI_ITEM(lip);

	xfs_bui_release(buip);
}

/*
 * The BUI has been either committed or aborted if the transaction has been
 * cancelled. If the transaction was cancelled, an BUD isn't going to be
 * constructed and thus we free the BUI here directly.
 */
STATIC void
xfs_bui_item_release(
	struct xfs_log_item	*lip)
{
	xfs_bui_release(BUI_ITEM(lip));
}

/*
 * Allocate and initialize an bui item with the given number of extents.
 */
STATIC struct xfs_bui_log_item *
xfs_bui_init(
	struct xfs_mount		*mp)

{
	struct xfs_bui_log_item		*buip;

	buip = kmem_cache_zalloc(xfs_bui_zone, GFP_KERNEL | __GFP_NOFAIL);

	xfs_log_item_init(mp, &buip->bui_item, XFS_LI_BUI, &xfs_bui_item_ops);
	buip->bui_format.bui_nextents = XFS_BUI_MAX_FAST_EXTENTS;
	buip->bui_format.bui_id = (uintptr_t)(void *)buip;
	atomic_set(&buip->bui_next_extent, 0);
	atomic_set(&buip->bui_refcount, 2);

	return buip;
}

static inline struct xfs_bud_log_item *BUD_ITEM(struct xfs_log_item *lip)
{
	return container_of(lip, struct xfs_bud_log_item, bud_item);
}

STATIC void
xfs_bud_item_size(
	struct xfs_log_item	*lip,
	int			*nvecs,
	int			*nbytes)
{
	*nvecs += 1;
	*nbytes += sizeof(struct xfs_bud_log_format);
}

/*
 * This is called to fill in the vector of log iovecs for the
 * given bud log item. We use only 1 iovec, and we point that
 * at the bud_log_format structure embedded in the bud item.
 * It is at this point that we assert that all of the extent
 * slots in the bud item have been filled.
 */
STATIC void
xfs_bud_item_format(
	struct xfs_log_item	*lip,
	struct xfs_log_vec	*lv)
{
	struct xfs_bud_log_item	*budp = BUD_ITEM(lip);
	struct xfs_log_iovec	*vecp = NULL;

	budp->bud_format.bud_type = XFS_LI_BUD;
	budp->bud_format.bud_size = 1;

	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_BUD_FORMAT, &budp->bud_format,
			sizeof(struct xfs_bud_log_format));
}

/*
 * The BUD is either committed or aborted if the transaction is cancelled. If
 * the transaction is cancelled, drop our reference to the BUI and free the
 * BUD.
 */
STATIC void
xfs_bud_item_release(
	struct xfs_log_item	*lip)
{
	struct xfs_bud_log_item	*budp = BUD_ITEM(lip);

	xfs_bui_release(budp->bud_buip);
	kmem_cache_free(xfs_bud_zone, budp);
}

static const struct xfs_item_ops xfs_bud_item_ops = {
	.flags		= XFS_ITEM_RELEASE_WHEN_COMMITTED,
	.iop_size	= xfs_bud_item_size,
	.iop_format	= xfs_bud_item_format,
	.iop_release	= xfs_bud_item_release,
};

static struct xfs_bud_log_item *
xfs_trans_get_bud(
	struct xfs_trans		*tp,
	struct xfs_bui_log_item		*buip)
{
	struct xfs_bud_log_item		*budp;

	budp = kmem_cache_zalloc(xfs_bud_zone, GFP_KERNEL | __GFP_NOFAIL);
	xfs_log_item_init(tp->t_mountp, &budp->bud_item, XFS_LI_BUD,
			  &xfs_bud_item_ops);
	budp->bud_buip = buip;
	budp->bud_format.bud_bui_id = buip->bui_format.bui_id;

	xfs_trans_add_item(tp, &budp->bud_item);
	return budp;
}

/*
 * Finish an bmap update and log it to the BUD. Note that the
 * transaction is marked dirty regardless of whether the bmap update
 * succeeds or fails to support the BUI/BUD lifecycle rules.
 */
static int
xfs_trans_log_finish_bmap_update(
	struct xfs_trans		*tp,
	struct xfs_bud_log_item		*budp,
	enum xfs_bmap_intent_type	type,
	struct xfs_inode		*ip,
	int				whichfork,
	xfs_fileoff_t			startoff,
	xfs_fsblock_t			startblock,
	xfs_filblks_t			*blockcount,
	xfs_exntst_t			state)
{
	int				error;

	error = xfs_bmap_finish_one(tp, ip, type, whichfork, startoff,
			startblock, blockcount, state);

	/*
	 * Mark the transaction dirty, even on error. This ensures the
	 * transaction is aborted, which:
	 *
	 * 1.) releases the BUI and frees the BUD
	 * 2.) shuts down the filesystem
	 */
	tp->t_flags |= XFS_TRANS_DIRTY;
	set_bit(XFS_LI_DIRTY, &budp->bud_item.