1 files changed, 508 insertions, 0 deletions
diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c
new file mode 100644
index 0000000..9bf57c7
--- /dev/null
+++ b/fs/xfs/xfs_bmap_item.c
@@ -0,0 +1,508 @@
+/*
+ * Copyright (C) 2016 Oracle.  All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * 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.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+#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_mount.h"
+#include "xfs_defer.h"
+#include "xfs_inode.h"
+#include "xfs_trans.h"
+#include "xfs_trans_priv.h"
+#include "xfs_buf_item.h"
+#include "xfs_bmap_item.h"
+#include "xfs_log.h"
+#include "xfs_bmap.h"
+#include "xfs_icache.h"
+#include "xfs_trace.h"
+
+
+kmem_zone_t	*xfs_bui_zone;
+kmem_zone_t	*xfs_bud_zone;
+
+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);
+}
+
+void
+xfs_bui_item_free(
+	struct xfs_bui_log_item	*buip)
+{
+	kmem_zone_free(xfs_bui_zone, 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));
+}
+
+/*
+ * Pinning has no meaning for an bui item, so just return.
+ */
+STATIC void
+xfs_bui_item_pin(
+	struct xfs_log_item	*lip)
+{
+}
+
+/*
+ * 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);
+}
+
+/*
+ * BUI items have no locking or pushing.  However, since BUIs are pulled from
+ * the AIL when their corresponding BUDs 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 BUI out of
+ * the AIL.
+ */
+STATIC uint
+xfs_bui_item_push(
+	struct xfs_log_item	*lip,
+	struct list_head	*buffer_list)
+{
+	return XFS_ITEM_PINNED;
+}
+
+/*
+ * 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_unlock(
+	struct xfs_log_item	*lip)
+{
+	if (lip->li_flags & XFS_LI_ABORTED)
+		xfs_bui_item_free(BUI_ITEM(lip));
+}
+
+/*
+ * The BUI is logged only once and cannot be moved in the log, so simply return
+ * the lsn at which it's been logged.
+ */
+STATIC xfs_lsn_t
+xfs_bui_item_committed(
+	struct xfs_log_item	*lip,
+	xfs_lsn_t		lsn)
+{
+	return lsn;
+}
+
+/*
+ * The BUI 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.
+ */
+STATIC void
+xfs_bui_item_committing(
+	struct xfs_log_item	*lip,
+	xfs_lsn_t		lsn)
+{
+}
+
+/*
+ * This is the ops vector shared by all bui log items.
+ */
+static const struct xfs_item_ops xfs_bui_item_ops = {
+	.iop_size	= xfs_bui_item_size,
+	.iop_format	= xfs_bui_item_format,
+	.iop_pin	= xfs_bui_item_pin,
+	.iop_unpin	= xfs_bui_item_unpin,
+	.iop_unlock	= xfs_bui_item_unlock,
+	.iop_committed	= xfs_bui_item_committed,
+	.iop_push	= xfs_bui_item_push,
+	.iop_committing = xfs_bui_item_committing,
+};
+
+/*
+ * Allocate and initialize an bui item with the given number of extents.
+ */
+struct xfs_bui_log_item *
+xfs_bui_init(
+	struct xfs_mount		*mp)
+
+{
+	struct xfs_bui_log_item		*buip;
+
+	buip = kmem_zone_zalloc(xfs_bui_zone, KM_SLEEP);
+
+	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;
+}
+
+/*
+ * 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.
+ */
+void
+xfs_bui_release(
+	struct xfs_bui_log_item	*buip)
+{
+	if (atomic_dec_and_test(&buip->bui_refcount)) {
+		xfs_trans_ail_remove(&buip->bui_item, SHUTDOWN_LOG_IO_ERROR);
+		xfs_bui_item_free(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));
+}
+
+/*
+ * Pinning has no meaning for an bud item, so just return.
+ */
+STATIC void
+xfs_bud_item_pin(
+	struct xfs_log_item	*lip)
+{
+}
+
+/*
+ * Since pinning has no meaning for an bud item, unpinning does
+ * not either.
+ */
+STATIC void
+xfs_bud_item_unpin(
+	struct xfs_log_item	*lip,
+	int			remove)
+{
+}
+
+/*
+ * There isn't much you can do to push on an bud item.  It is simply stuck
+ * waiting for the log to be flushed to disk.
+ */
+STATIC uint
+xfs_bud_item_push(
+	struct xfs_log_item	*lip,
+	struct list_head	*buffer_list)
+{
+	return XFS_ITEM_PINNED;
+}
+
+/*
+ * 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_unlock(
+	struct xfs_log_item	*lip)
+{
+	struct xfs_bud_log_item	*budp = BUD_ITEM(lip);
+
+	if (lip->li_flags & XFS_LI_ABORTED) {
+		xfs_bui_release(budp->bud_buip);
+		kmem_zone_free(xfs_bud_zone, budp);
+	}
+}
+
+/*
+ * When the bud item is committed to disk, all we need to do is delete our
+ * reference to our partner bui item and then free ourselves. Since we're
+ * freeing ourselves we must return -1 to keep the transaction code from
+ * further referencing this item.
+ */
+STATIC xfs_lsn_t
+xfs_bud_item_committed(
+	struct xfs_log_item	*lip,
+	xfs_lsn_t		lsn)
+{
+	struct xfs_bud_log_item	*budp = BUD_ITEM(lip);
+
+	/*
+	 * Drop the BUI reference regardless of whether the BUD has been
+	 * aborted. Once the BUD transaction is constructed, it is the sole
+	 * responsibility of the BUD to release the BUI (even if the BUI is
+	 * aborted due to log I/O error).
+	 */
+	xfs_bui_release(budp->bud_buip);
+	kmem_zone_free(xfs_bud_zone, budp);
+
+	return (xfs_lsn_t)-1;
+}
+
+/*
+ * The BUD 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.
+ */
+STATIC void
+xfs_bud_item_committing(
+	struct xfs_log_item	*lip,
+	xfs_lsn_t		lsn)
+{
+}
+
+/*
+ * This is the ops vector shared by all bud log items.
+ */
+static const struct xfs_item_ops xfs_bud_item_ops = {
+	.iop_size	= xfs_bud_item_size,
+	.iop_format	= xfs_bud_item_format,
+	.iop_pin	= xfs_bud_item_pin,
+	.iop_unpin	= xfs_bud_item_unpin,
+	.iop_unlock	= xfs_bud_item_unlock,
+	.iop_committed	= xfs_bud_item_committed,
+	.iop_push	= xfs_bud_item_push,
+	.iop_committing = xfs_bud_item_committing,
+};
+
+/*
+ * Allocate and initialize an bud item with the given number of extents.
+ */
+struct xfs_bud_log_item *
+xfs_bud_init(
+	struct xfs_mount		*mp,
+	struct xfs_bui_log_item		*buip)
+
+{
+	struct xfs_bud_log_item	*budp;
+
+	budp = kmem_zone_zalloc(xfs_bud_zone, KM_SLEEP);
+	xfs_log_item_init(mp, &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;
+
+	return budp;
+}
+
+/*
+ * Process a bmap update intent item that was recovered from the log.
+ * We need to update some inode's bmbt.
+ */
+int
+xfs_bui_recover(
+	struct xfs_mount		*mp,
+	struct xfs_bui_log_item		*buip)
+{
+	int				error = 0;
+	unsigned int			bui_type;
+	struct xfs_map_extent		*bmap;
+	xfs_fsblock_t			startblock_fsb;
+	xfs_fsblock_t			inode_fsb;
+	bool				op_ok;
+	struct xfs_bud_log_item		*budp;
+	enum xfs_bmap_intent_type	type;
+	int				whichfork;
+	xfs_exntst_t			state;
+	struct xfs_trans		*tp;
+	struct xfs_inode		*ip = NULL;
+	struct xfs_defer_ops		dfops;
+	xfs_fsblock_t			firstfsb;
+
+	ASSERT(!test_bit(XFS_BUI_RECOVERED, &buip->bui_flags));
+
+	/* Only one mapping operation per BUI... */
+	if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS) {
+		set_bit(XFS_BUI_RECOVERED, &buip->bui_flags);
+		xfs_bui_release(buip);
+		return -EIO;
+	}
+
+	/*
+	 * First check the validity of the extent described by the
+	 * BUI.  If anything is bad, then toss the BUI.
+	 */
+	bmap = &buip->bui_format.bui_extents[0];
+	startblock_fsb = XFS_BB_TO_FSB(mp,
+			   XFS_FSB_TO_DADDR(mp, bmap->me_startblock));
+	inode_fsb = XFS_BB_TO_FSB(mp, XFS_FSB_TO_DADDR(mp,
+			XFS_INO_TO_FSB(mp, bmap->me_owner)));
+	switch (bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK) {
+	case XFS_BMAP_MAP:
+	case XFS_BMAP_UNMAP:
+		op_ok = true;
+		break;
+	default:
+		op_ok = false;
+		break;
+	}
+	if (!op_ok || startblock_fsb == 0 ||
+	    bmap->me_len == 0 ||
+	    inode_fsb == 0 ||
+	    startblock_fsb >= mp->m_sb.sb_dblocks ||
+	    bmap->me_len >= mp->m_sb.sb_agblocks ||
+	    inode_fsb >= mp->m_sb.sb_dblocks ||
+	    (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS)) {
+		/*
+		 * This will pull the BUI from the AIL and
+		 * free the memory associated with it.
+		 */
+		set_bit(XFS_BUI_RECOVERED, &buip->bui_flags);
+		xfs_bui_release(buip);
+		return -EIO;
+	}
+
+	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
+	if (error)
+		return error;
+	budp = xfs_trans_get_bud(tp, buip);
+
+	/* Grab the inode. */
+	error = xfs_iget(mp, tp, bmap->me_owner, 0, XFS_ILOCK_EXCL, &ip);
+	if (error)
+		goto err_inode;
+
+	if (VFS_I(ip)->i_nlink == 0)
+		xfs_iflags_set(ip, XFS_IRECOVERY);
+	xfs_defer_init(&dfops, &firstfsb);
+
+	/* Process deferred bmap item. */
+	state = (bmap->me_flags & XFS_BMAP_EXTENT_UNWRITTEN) ?
+			XFS_EXT_UNWRITTEN : XFS_EXT_NORM;
+	whichfork = (bmap->me_flags & XFS_BMAP_EXTENT_ATTR_FORK) ?
+			XFS_ATTR_FORK : XFS_DATA_FORK;
+	bui_type = bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK;
+	switch (bui_type) {
+	case XFS_BMAP_MAP:
+	case XFS_BMAP_UNMAP:
+		type = bui_type;
+		break;
+	default:
+		error = -EFSCORRUPTED;
+		goto err_dfops;
+	}
+	xfs_trans_ijoin(tp, ip, 0);
+
+	error = xfs_trans_log_finish_bmap_update(tp, budp, &dfops, type,
+			ip, whichfork, bmap->me_startoff,
+			bmap->me_startblock, bmap->me_len,
+			state);
+	if (error)
+		goto err_dfops;
+
+	/* Finish transaction, free inodes. */
+	error = xfs_defer_finish(&tp, &dfops, NULL);
+	if (error)
+		goto err_dfops;
+
+	set_bit(XFS_BUI_RECOVERED, &buip->bui_flags);
+	error = xfs_trans_commit(tp);
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	IRELE(ip);
+
+	return error;
+
+err_dfops:
+	xfs_defer_cancel(&dfops);
+err_inode:
+	xfs_trans_cancel(tp);
+	if (ip) {
+		xfs_iunlock(ip, XFS_ILOCK_EXCL);
+		IRELE(ip);
+	}
+	return error;
+}