patch-2.4.25 linux-2.4.25/fs/xfs/xfs_extfree_item.c

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diff -urN linux-2.4.24/fs/xfs/xfs_extfree_item.c linux-2.4.25/fs/xfs/xfs_extfree_item.c
@@ -0,0 +1,668 @@
+/*
+ * Copyright (c) 2000-2001 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+
+/*
+ * This file contains the implementation of the xfs_efi_log_item
+ * and xfs_efd_log_item items.
+ */
+
+#include "xfs.h"
+
+#include "xfs_macros.h"
+#include "xfs_types.h"
+#include "xfs_inum.h"
+#include "xfs_log.h"
+#include "xfs_trans.h"
+#include "xfs_buf_item.h"
+#include "xfs_sb.h"
+#include "xfs_dir.h"
+#include "xfs_dmapi.h"
+#include "xfs_mount.h"
+#include "xfs_trans_priv.h"
+#include "xfs_extfree_item.h"
+
+
+kmem_zone_t	*xfs_efi_zone;
+kmem_zone_t	*xfs_efd_zone;
+
+STATIC void	xfs_efi_item_unlock(xfs_efi_log_item_t *);
+STATIC void	xfs_efi_item_abort(xfs_efi_log_item_t *);
+STATIC void	xfs_efd_item_abort(xfs_efd_log_item_t *);
+
+
+
+/*
+ * This returns the number of iovecs needed to log the given efi item.
+ * We only need 1 iovec for an efi item.  It just logs the efi_log_format
+ * structure.
+ */
+/*ARGSUSED*/
+STATIC uint
+xfs_efi_item_size(xfs_efi_log_item_t *efip)
+{
+	return 1;
+}
+
+/*
+ * This is called to fill in the vector of log iovecs for the
+ * given efi log item. We use only 1 iovec, and we point that
+ * at the efi_log_format structure embedded in the efi item.
+ * It is at this point that we assert that all of the extent
+ * slots in the efi item have been filled.
+ */
+STATIC void
+xfs_efi_item_format(xfs_efi_log_item_t	*efip,
+		    xfs_log_iovec_t	*log_vector)
+{
+	uint	size;
+
+	ASSERT(efip->efi_next_extent == efip->efi_format.efi_nextents);
+
+	efip->efi_format.efi_type = XFS_LI_EFI;
+
+	size = sizeof(xfs_efi_log_format_t);
+	size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
+	efip->efi_format.efi_size = 1;
+
+	log_vector->i_addr = (xfs_caddr_t)&(efip->efi_format);
+	log_vector->i_len = size;
+	ASSERT(size >= sizeof(xfs_efi_log_format_t));
+}
+
+
+/*
+ * Pinning has no meaning for an efi item, so just return.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efi_item_pin(xfs_efi_log_item_t *efip)
+{
+	return;
+}
+
+
+/*
+ * While EFIs cannot really be pinned, the unpin operation is the
+ * last place at which the EFI is manipulated during a transaction.
+ * Here we coordinate with xfs_efi_cancel() to determine who gets to
+ * free the EFI.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efi_item_unpin(xfs_efi_log_item_t *efip, int stale)
+{
+	int		nexts;
+	int		size;
+	xfs_mount_t	*mp;
+	SPLDECL(s);
+
+	mp = efip->efi_item.li_mountp;
+	AIL_LOCK(mp, s);
+	if (efip->efi_flags & XFS_EFI_CANCELED) {
+		/*
+		 * xfs_trans_delete_ail() drops the AIL lock.
+		 */
+		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
+
+		nexts = efip->efi_format.efi_nextents;
+		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
+			size = sizeof(xfs_efi_log_item_t);
+			size += (nexts - 1) * sizeof(xfs_extent_t);
+			kmem_free(efip, size);
+		} else {
+			kmem_zone_free(xfs_efi_zone, efip);
+		}
+	} else {
+		efip->efi_flags |= XFS_EFI_COMMITTED;
+		AIL_UNLOCK(mp, s);
+	}
+
+	return;
+}
+
+/*
+ * like unpin only we have to also clear the xaction descriptor
+ * pointing the log item if we free the item.  This routine duplicates
+ * unpin because efi_flags is protected by the AIL lock.  Freeing
+ * the descriptor and then calling unpin would force us to drop the AIL
+ * lock which would open up a race condition.
+ */
+STATIC void
+xfs_efi_item_unpin_remove(xfs_efi_log_item_t *efip, xfs_trans_t *tp)
+{
+	int		nexts;
+	int		size;
+	xfs_mount_t	*mp;
+	xfs_log_item_desc_t	*lidp;
+	SPLDECL(s);
+
+	mp = efip->efi_item.li_mountp;
+	AIL_LOCK(mp, s);
+	if (efip->efi_flags & XFS_EFI_CANCELED) {
+		/*
+		 * free the xaction descriptor pointing to this item
+		 */
+		lidp = xfs_trans_find_item(tp, (xfs_log_item_t *) efip);
+		xfs_trans_free_item(tp, lidp);
+		/*
+		 * pull the item off the AIL.
+		 * xfs_trans_delete_ail() drops the AIL lock.
+		 */
+		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
+		/*
+		 * now free the item itself
+		 */
+		nexts = efip->efi_format.efi_nextents;
+		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
+			size = sizeof(xfs_efi_log_item_t);
+			size += (nexts - 1) * sizeof(xfs_extent_t);
+			kmem_free(efip, size);
+		} else {
+			kmem_zone_free(xfs_efi_zone, efip);
+		}
+	} else {
+		efip->efi_flags |= XFS_EFI_COMMITTED;
+		AIL_UNLOCK(mp, s);
+	}
+
+	return;
+}
+
+/*
+ * Efi items have no locking or pushing.  However, since EFIs are
+ * pulled from the AIL when their corresponding EFDs are committed
+ * to disk, their situation is very similar to being pinned.  Return
+ * XFS_ITEM_PINNED so that the caller will eventually flush the log.
+ * This should help in getting the EFI out of the AIL.
+ */
+/*ARGSUSED*/
+STATIC uint
+xfs_efi_item_trylock(xfs_efi_log_item_t *efip)
+{
+	return XFS_ITEM_PINNED;
+}
+
+/*
+ * Efi items have no locking, so just return.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efi_item_unlock(xfs_efi_log_item_t *efip)
+{
+	if (efip->efi_item.li_flags & XFS_LI_ABORTED)
+		xfs_efi_item_abort(efip);
+	return;
+}
+
+/*
+ * The EFI is logged only once and cannot be moved in the log, so
+ * simply return the lsn at which it's been logged.  The canceled
+ * flag is not paid any attention here.  Checking for that is delayed
+ * until the EFI is unpinned.
+ */
+/*ARGSUSED*/
+STATIC xfs_lsn_t
+xfs_efi_item_committed(xfs_efi_log_item_t *efip, xfs_lsn_t lsn)
+{
+	return lsn;
+}
+
+/*
+ * This is called when the transaction logging the EFI is aborted.
+ * Free up the EFI and return.  No need to clean up the slot for
+ * the item in the transaction.  That was done by the unpin code
+ * which is called prior to this routine in the abort/fs-shutdown path.
+ */
+STATIC void
+xfs_efi_item_abort(xfs_efi_log_item_t *efip)
+{
+	int	nexts;
+	int	size;
+
+	nexts = efip->efi_format.efi_nextents;
+	if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
+		size = sizeof(xfs_efi_log_item_t);
+		size += (nexts - 1) * sizeof(xfs_extent_t);
+		kmem_free(efip, size);
+	} else {
+		kmem_zone_free(xfs_efi_zone, efip);
+	}
+	return;
+}
+
+/*
+ * There isn't much you can do to push on an efi item.  It is simply
+ * stuck waiting for all of its corresponding efd items to be
+ * committed to disk.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efi_item_push(xfs_efi_log_item_t *efip)
+{
+	return;
+}
+
+/*
+ * The EFI dependency tracking op doesn't do squat.  It can't because
+ * it doesn't know where the free extent is coming from.  The dependency
+ * tracking has to be handled by the "enclosing" metadata object.  For
+ * example, for inodes, the inode is locked throughout the extent freeing
+ * so the dependency should be recorded there.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efi_item_committing(xfs_efi_log_item_t *efip, xfs_lsn_t lsn)
+{
+	return;
+}
+
+/*
+ * This is the ops vector shared by all efi log items.
+ */
+struct xfs_item_ops xfs_efi_item_ops = {
+	.iop_size	= (uint(*)(xfs_log_item_t*))xfs_efi_item_size,
+	.iop_format	= (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
+					xfs_efi_item_format,
+	.iop_pin	= (void(*)(xfs_log_item_t*))xfs_efi_item_pin,
+	.iop_unpin	= (void(*)(xfs_log_item_t*, int))xfs_efi_item_unpin,
+	.iop_unpin_remove = (void(*)(xfs_log_item_t*, xfs_trans_t *))
+					xfs_efi_item_unpin_remove,
+	.iop_trylock	= (uint(*)(xfs_log_item_t*))xfs_efi_item_trylock,
+	.iop_unlock	= (void(*)(xfs_log_item_t*))xfs_efi_item_unlock,
+	.iop_committed	= (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
+					xfs_efi_item_committed,
+	.iop_push	= (void(*)(xfs_log_item_t*))xfs_efi_item_push,
+	.iop_abort	= (void(*)(xfs_log_item_t*))xfs_efi_item_abort,
+	.iop_pushbuf	= NULL,
+	.iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
+					xfs_efi_item_committing
+};
+
+
+/*
+ * Allocate and initialize an efi item with the given number of extents.
+ */
+xfs_efi_log_item_t *
+xfs_efi_init(xfs_mount_t	*mp,
+	     uint		nextents)
+
+{
+	xfs_efi_log_item_t	*efip;
+	uint			size;
+
+	ASSERT(nextents > 0);
+	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
+		size = (uint)(sizeof(xfs_efi_log_item_t) +
+			((nextents - 1) * sizeof(xfs_extent_t)));
+		efip = (xfs_efi_log_item_t*)kmem_zalloc(size, KM_SLEEP);
+	} else {
+		efip = (xfs_efi_log_item_t*)kmem_zone_zalloc(xfs_efi_zone,
+							     KM_SLEEP);
+	}
+
+	efip->efi_item.li_type = XFS_LI_EFI;
+	efip->efi_item.li_ops = &xfs_efi_item_ops;
+	efip->efi_item.li_mountp = mp;
+	efip->efi_format.efi_nextents = nextents;
+	efip->efi_format.efi_id = (__psint_t)(void*)efip;
+
+	return (efip);
+}
+
+/*
+ * This is called by the efd item code below to release references to
+ * the given efi item.  Each efd calls this with the number of
+ * extents that it has logged, and when the sum of these reaches
+ * the total number of extents logged by this efi item we can free
+ * the efi item.
+ *
+ * Freeing the efi item requires that we remove it from the AIL.
+ * We'll use the AIL lock to protect our counters as well as
+ * the removal from the AIL.
+ */
+void
+xfs_efi_release(xfs_efi_log_item_t	*efip,
+		uint			nextents)
+{
+	xfs_mount_t	*mp;
+	int		extents_left;
+	uint		size;
+	int		nexts;
+	SPLDECL(s);
+
+	mp = efip->efi_item.li_mountp;
+	ASSERT(efip->efi_next_extent > 0);
+	ASSERT(efip->efi_flags & XFS_EFI_COMMITTED);
+
+	AIL_LOCK(mp, s);
+	ASSERT(efip->efi_next_extent >= nextents);
+	efip->efi_next_extent -= nextents;
+	extents_left = efip->efi_next_extent;
+	if (extents_left == 0) {
+		/*
+		 * xfs_trans_delete_ail() drops the AIL lock.
+		 */
+		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
+	} else {
+		AIL_UNLOCK(mp, s);
+	}
+
+	if (extents_left == 0) {
+		nexts = efip->efi_format.efi_nextents;
+		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
+			size = sizeof(xfs_efi_log_item_t);
+			size += (nexts - 1) * sizeof(xfs_extent_t);
+			kmem_free(efip, size);
+		} else {
+			kmem_zone_free(xfs_efi_zone, efip);
+		}
+	}
+}
+
+/*
+ * This is called when the transaction that should be committing the
+ * EFD corresponding to the given EFI is aborted.  The committed and
+ * canceled flags are used to coordinate the freeing of the EFI and
+ * the references by the transaction that committed it.
+ */
+STATIC void
+xfs_efi_cancel(
+	xfs_efi_log_item_t	*efip)
+{
+	int		nexts;
+	int		size;
+	xfs_mount_t	*mp;
+	SPLDECL(s);
+
+	mp = efip->efi_item.li_mountp;
+	AIL_LOCK(mp, s);
+	if (efip->efi_flags & XFS_EFI_COMMITTED) {
+		/*
+		 * xfs_trans_delete_ail() drops the AIL lock.
+		 */
+		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
+
+		nexts = efip->efi_format.efi_nextents;
+		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
+			size = sizeof(xfs_efi_log_item_t);
+			size += (nexts - 1) * sizeof(xfs_extent_t);
+			kmem_free(efip, size);
+		} else {
+			kmem_zone_free(xfs_efi_zone, efip);
+		}
+	} else {
+		efip->efi_flags |= XFS_EFI_CANCELED;
+		AIL_UNLOCK(mp, s);
+	}
+
+	return;
+}
+
+
+
+
+
+/*
+ * This returns the number of iovecs needed to log the given efd item.
+ * We only need 1 iovec for an efd item.  It just logs the efd_log_format
+ * structure.
+ */
+/*ARGSUSED*/
+STATIC uint
+xfs_efd_item_size(xfs_efd_log_item_t *efdp)
+{
+	return 1;
+}
+
+/*
+ * This is called to fill in the vector of log iovecs for the
+ * given efd log item. We use only 1 iovec, and we point that
+ * at the efd_log_format structure embedded in the efd item.
+ * It is at this point that we assert that all of the extent
+ * slots in the efd item have been filled.
+ */
+STATIC void
+xfs_efd_item_format(xfs_efd_log_item_t	*efdp,
+		    xfs_log_iovec_t	*log_vector)
+{
+	uint	size;
+
+	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
+
+	efdp->efd_format.efd_type = XFS_LI_EFD;
+
+	size = sizeof(xfs_efd_log_format_t);
+	size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
+	efdp->efd_format.efd_size = 1;
+
+	log_vector->i_addr = (xfs_caddr_t)&(efdp->efd_format);
+	log_vector->i_len = size;
+	ASSERT(size >= sizeof(xfs_efd_log_format_t));
+}
+
+
+/*
+ * Pinning has no meaning for an efd item, so just return.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efd_item_pin(xfs_efd_log_item_t *efdp)
+{
+	return;
+}
+
+
+/*
+ * Since pinning has no meaning for an efd item, unpinning does
+ * not either.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efd_item_unpin(xfs_efd_log_item_t *efdp, int stale)
+{
+	return;
+}
+
+/*ARGSUSED*/
+STATIC void
+xfs_efd_item_unpin_remove(xfs_efd_log_item_t *efdp, xfs_trans_t *tp)
+{
+	return;
+}
+
+/*
+ * Efd items have no locking, so just return success.
+ */
+/*ARGSUSED*/
+STATIC uint
+xfs_efd_item_trylock(xfs_efd_log_item_t *efdp)
+{
+	return XFS_ITEM_LOCKED;
+}
+
+/*
+ * Efd items have no locking or pushing, so return failure
+ * so that the caller doesn't bother with us.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efd_item_unlock(xfs_efd_log_item_t *efdp)
+{
+	if (efdp->efd_item.li_flags & XFS_LI_ABORTED)
+		xfs_efd_item_abort(efdp);
+	return;
+}
+
+/*
+ * When the efd item is committed to disk, all we need to do
+ * is delete our reference to our partner efi item and then
+ * free ourselves.  Since we're freeing ourselves we must
+ * return -1 to keep the transaction code from further referencing
+ * this item.
+ */
+/*ARGSUSED*/
+STATIC xfs_lsn_t
+xfs_efd_item_committed(xfs_efd_log_item_t *efdp, xfs_lsn_t lsn)
+{
+	uint	size;
+	int	nexts;
+
+	/*
+	 * If we got a log I/O error, it's always the case that the LR with the
+	 * EFI got unpinned and freed before the EFD got aborted.
+	 */
+	if ((efdp->efd_item.li_flags & XFS_LI_ABORTED) == 0)
+		xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
+
+	nexts = efdp->efd_format.efd_nextents;
+	if (nexts > XFS_EFD_MAX_FAST_EXTENTS) {
+		size = sizeof(xfs_efd_log_item_t);
+		size += (nexts - 1) * sizeof(xfs_extent_t);
+		kmem_free(efdp, size);
+	} else {
+		kmem_zone_free(xfs_efd_zone, efdp);
+	}
+
+	return (xfs_lsn_t)-1;
+}
+
+/*
+ * The transaction of which this EFD is a part has been aborted.
+ * Inform its companion EFI of this fact and then clean up after
+ * ourselves.  No need to clean up the slot for the item in the
+ * transaction.  That was done by the unpin code which is called
+ * prior to this routine in the abort/fs-shutdown path.
+ */
+STATIC void
+xfs_efd_item_abort(xfs_efd_log_item_t *efdp)
+{
+	int	nexts;
+	int	size;
+
+	/*
+	 * If we got a log I/O error, it's always the case that the LR with the
+	 * EFI got unpinned and freed before the EFD got aborted. So don't
+	 * reference the EFI at all in that case.
+	 */
+	if ((efdp->efd_item.li_flags & XFS_LI_ABORTED) == 0)
+		xfs_efi_cancel(efdp->efd_efip);
+
+	nexts = efdp->efd_format.efd_nextents;
+	if (nexts > XFS_EFD_MAX_FAST_EXTENTS) {
+		size = sizeof(xfs_efd_log_item_t);
+		size += (nexts - 1) * sizeof(xfs_extent_t);
+		kmem_free(efdp, size);
+	} else {
+		kmem_zone_free(xfs_efd_zone, efdp);
+	}
+	return;
+}
+
+/*
+ * There isn't much you can do to push on an efd item.  It is simply
+ * stuck waiting for the log to be flushed to disk.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efd_item_push(xfs_efd_log_item_t *efdp)
+{
+	return;
+}
+
+/*
+ * The EFD dependency tracking op doesn't do squat.  It can't because
+ * it doesn't know where the free extent is coming from.  The dependency
+ * tracking has to be handled by the "enclosing" metadata object.  For
+ * example, for inodes, the inode is locked throughout the extent freeing
+ * so the dependency should be recorded there.
+ */
+/*ARGSUSED*/
+STATIC void
+xfs_efd_item_committing(xfs_efd_log_item_t *efip, xfs_lsn_t lsn)
+{
+	return;
+}
+
+/*
+ * This is the ops vector shared by all efd log items.
+ */
+struct xfs_item_ops xfs_efd_item_ops = {
+	.iop_size	= (uint(*)(xfs_log_item_t*))xfs_efd_item_size,
+	.iop_format	= (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
+					xfs_efd_item_format,
+	.iop_pin	= (void(*)(xfs_log_item_t*))xfs_efd_item_pin,
+	.iop_unpin	= (void(*)(xfs_log_item_t*, int))xfs_efd_item_unpin,
+	.iop_unpin_remove = (void(*)(xfs_log_item_t*, xfs_trans_t*))
+					xfs_efd_item_unpin_remove,
+	.iop_trylock	= (uint(*)(xfs_log_item_t*))xfs_efd_item_trylock,
+	.iop_unlock	= (void(*)(xfs_log_item_t*))xfs_efd_item_unlock,
+	.iop_committed	= (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
+					xfs_efd_item_committed,
+	.iop_push	= (void(*)(xfs_log_item_t*))xfs_efd_item_push,
+	.iop_abort	= (void(*)(xfs_log_item_t*))xfs_efd_item_abort,
+	.iop_pushbuf	= NULL,
+	.iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
+					xfs_efd_item_committing
+};
+
+
+/*
+ * Allocate and initialize an efd item with the given number of extents.
+ */
+xfs_efd_log_item_t *
+xfs_efd_init(xfs_mount_t	*mp,
+	     xfs_efi_log_item_t	*efip,
+	     uint		nextents)
+
+{
+	xfs_efd_log_item_t	*efdp;
+	uint			size;
+
+	ASSERT(nextents > 0);
+	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
+		size = (uint)(sizeof(xfs_efd_log_item_t) +
+			((nextents - 1) * sizeof(xfs_extent_t)));
+		efdp = (xfs_efd_log_item_t*)kmem_zalloc(size, KM_SLEEP);
+	} else {
+		efdp = (xfs_efd_log_item_t*)kmem_zone_zalloc(xfs_efd_zone,
+							     KM_SLEEP);
+	}
+
+	efdp->efd_item.li_type = XFS_LI_EFD;
+	efdp->efd_item.li_ops = &xfs_efd_item_ops;
+	efdp->efd_item.li_mountp = mp;
+	efdp->efd_efip = efip;
+	efdp->efd_format.efd_nextents = nextents;
+	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
+
+	return (efdp);
+}
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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)