Merge tag 'xfs-rmap-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull more xfs updates from Dave Chinner:
 "This is the second part of the XFS updates for this merge cycle, and
  contains the new reverse block mapping feature for XFS.

  Reverse mapping allows us to track the owner of a specific block on
  disk precisely.  It is implemented as a set of btrees (one per
  allocation group) that track the owners of allocated extents.
  Effectively it is a "used space tree" that is updated when we allocate
  or free extents.  i.e. it is coherent with the free space btrees we
  already maintain and never overlaps with them.

  This reverse mapping infrastructure is the building block of several
  upcoming features - reflink, copy-on-write data, dedupe, online
  metadata and data scrubbing, highly accurate bad sector/data loss
  reporting to users, and significantly improved reconstruction of
  damaged and corrupted filesystems.  There's a lot of new stuff coming
  along in the next couple of cycles,a nd it all builds in the rmap
  infrastructure.

  As such, it's a huge chunk of new code with new on-disk format
  features and internal infrastructure.  It warns at mount time as an
  experimental feature and that it may eat data (as we do with all new
  on-disk features until they stabilise).  We have not released
  userspace suport for it yet - userspace support currently requires
  download from Darrick's xfsprogs repo and build from source, so the
  access to this feature is really developer/tester only at this point.
  Initial userspace support will be released at the same time kernel
  with this code in it is released.

  The new rmap enabled code regresses 3 xfstests - all are ENOSPC
  related corner cases, one of which Darrick posted a fix for a few
  hours ago.  The other two are fixed by infrastructure that is part of
  the upcoming reflink patchset.  This new ENOSPC infrastructure
  requires a on-disk format tweak required to keep mount times in
  check - we need to keep an on-disk count of allocated rmapbt blocks so
  we don't have to scan the entire btrees at mount time to count them.

  This is currently being tested and will be part of the fixes sent in
  the next week or two so users will not be exposed to this change"

* tag 'xfs-rmap-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (52 commits)
  xfs: move (and rename) the deferred bmap-free tracepoints
  xfs: collapse single use static functions
  xfs: remove unnecessary parentheses from log redo item recovery functions
  xfs: remove the extents array from the rmap update done log item
  xfs: in btree_lshift, only allocate temporary cursor when needed
  xfs: remove unnecesary lshift/rshift key initialization
  xfs: remove the get*keys and update_keys btree ops pointers
  xfs: enable the rmap btree functionality
  xfs: don't update rmapbt when fixing agfl
  xfs: disable XFS_IOC_SWAPEXT when rmap btree is enabled
  xfs: add rmap btree block detection to log recovery
  xfs: add rmap btree geometry feature flag
  xfs: propagate bmap updates to rmapbt
  xfs: enable the xfs_defer mechanism to process rmaps to update
  xfs: log rmap intent items
  xfs: create rmap update intent log items
  xfs: add rmap btree insert and delete helpers
  xfs: convert unwritten status of reverse mappings
  xfs: remove an extent from the rmap btree
  xfs: add an extent to the rmap btree
  ...

1 files changed, 271 insertions, 0 deletions

diff --git a/fs/xfs/xfs_trans_rmap.c b/fs/xfs/xfs_trans_rmap.c
new file mode 100644
index 000000000000..5a50ef881568
--- /dev/null
+++ b/fs/xfs/xfs_trans_rmap.c
@@ -0,0 +1,271 @@
+/*
+ * 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_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_trans.h"
+#include "xfs_trans_priv.h"
+#include "xfs_rmap_item.h"
+#include "xfs_alloc.h"
+#include "xfs_rmap.h"
+
+/* Set the map extent flags for this reverse mapping. */
+static void
+xfs_trans_set_rmap_flags(
+	struct xfs_map_extent		*rmap,
+	enum xfs_rmap_intent_type	type,
+	int				whichfork,
+	xfs_exntst_t			state)
+{
+	rmap->me_flags = 0;
+	if (state == XFS_EXT_UNWRITTEN)
+		rmap->me_flags |= XFS_RMAP_EXTENT_UNWRITTEN;
+	if (whichfork == XFS_ATTR_FORK)
+		rmap->me_flags |= XFS_RMAP_EXTENT_ATTR_FORK;
+	switch (type) {
+	case XFS_RMAP_MAP:
+		rmap->me_flags |= XFS_RMAP_EXTENT_MAP;
+		break;
+	case XFS_RMAP_UNMAP:
+		rmap->me_flags |= XFS_RMAP_EXTENT_UNMAP;
+		break;
+	case XFS_RMAP_CONVERT:
+		rmap->me_flags |= XFS_RMAP_EXTENT_CONVERT;
+		break;
+	case XFS_RMAP_ALLOC:
+		rmap->me_flags |= XFS_RMAP_EXTENT_ALLOC;
+		break;
+	case XFS_RMAP_FREE:
+		rmap->me_flags |= XFS_RMAP_EXTENT_FREE;
+		break;
+	default:
+		ASSERT(0);
+	}
+}
+
+struct xfs_rud_log_item *
+xfs_trans_get_rud(
+	struct xfs_trans		*tp,
+	struct xfs_rui_log_item		*ruip)
+{
+	struct xfs_rud_log_item		*rudp;
+
+	rudp = xfs_rud_init(tp->t_mountp, ruip);
+	xfs_trans_add_item(tp, &rudp->rud_item);
+	return rudp;
+}
+
+/*
+ * Finish an rmap update and log it to the RUD. Note that the transaction is
+ * marked dirty regardless of whether the rmap update succeeds or fails to
+ * support the RUI/RUD lifecycle rules.
+ */
+int
+xfs_trans_log_finish_rmap_update(
+	struct xfs_trans		*tp,
+	struct xfs_rud_log_item		*rudp,
+	enum xfs_rmap_intent_type	type,
+	__uint64_t			owner,
+	int				whichfork,
+	xfs_fileoff_t			startoff,
+	xfs_fsblock_t			startblock,
+	xfs_filblks_t			blockcount,
+	xfs_exntst_t			state,
+	struct xfs_btree_cur		**pcur)
+{
+	int				error;
+
+	error = xfs_rmap_finish_one(tp, type, owner, whichfork, startoff,
+			startblock, blockcount, state, pcur);
+
+	/*
+	 * Mark the transaction dirty, even on error. This ensures the
+	 * transaction is aborted, which:
+	 *
+	 * 1.) releases the RUI and frees the RUD
+	 * 2.) shuts down the filesystem
+	 */
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	rudp->rud_item.li_desc->lid_flags |= XFS_LID_DIRTY;
+
+	return error;
+}
+
+/* Sort rmap intents by AG. */
+static int
+xfs_rmap_update_diff_items(
+	void				*priv,
+	struct list_head		*a,
+	struct list_head		*b)
+{
+	struct xfs_mount		*mp = priv;
+	struct xfs_rmap_intent		*ra;
+	struct xfs_rmap_intent		*rb;
+
+	ra = container_of(a, struct xfs_rmap_intent, ri_list);
+	rb = container_of(b, struct xfs_rmap_intent, ri_list);
+	return  XFS_FSB_TO_AGNO(mp, ra->ri_bmap.br_startblock) -
+		XFS_FSB_TO_AGNO(mp, rb->ri_bmap.br_startblock);
+}
+
+/* Get an RUI. */
+STATIC void *
+xfs_rmap_update_create_intent(
+	struct xfs_trans		*tp,
+	unsigned int			count)
+{
+	struct xfs_rui_log_item		*ruip;
+
+	ASSERT(tp != NULL);
+	ASSERT(count > 0);
+
+	ruip = xfs_rui_init(tp->t_mountp, count);
+	ASSERT(ruip != NULL);
+
+	/*
+	 * Get a log_item_desc to point at the new item.
+	 */
+	xfs_trans_add_item(tp, &ruip->rui_item);
+	return ruip;
+}
+
+/* Log rmap updates in the intent item. */
+STATIC void
+xfs_rmap_update_log_item(
+	struct xfs_trans		*tp,
+	void				*intent,
+	struct list_head		*item)
+{
+	struct xfs_rui_log_item		*ruip = intent;
+	struct xfs_rmap_intent		*rmap;
+	uint				next_extent;
+	struct xfs_map_extent		*map;
+
+	rmap = container_of(item, struct xfs_rmap_intent, ri_list);
+
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	ruip->rui_item.li_desc->lid_flags |= XFS_LID_DIRTY;
+
+	/*
+	 * atomic_inc_return gives us the value after the increment;
+	 * we want to use it as an array index so we need to subtract 1 from
+	 * it.
+	 */
+	next_extent = atomic_inc_return(&ruip->rui_next_extent) - 1;
+	ASSERT(next_extent < ruip->rui_format.rui_nextents);
+	map = &ruip->rui_format.rui_extents[next_extent];
+	map->me_owner = rmap->ri_owner;
+	map->me_startblock = rmap->ri_bmap.br_startblock;
+	map->me_startoff = rmap->ri_bmap.br_startoff;
+	map->me_len = rmap->ri_bmap.br_blockcount;
+	xfs_trans_set_rmap_flags(map, rmap->ri_type, rmap->ri_whichfork,
+			rmap->ri_bmap.br_state);
+}
+
+/* Get an RUD so we can process all the deferred rmap updates. */
+STATIC void *
+xfs_rmap_update_create_done(
+	struct xfs_trans		*tp,
+	void				*intent,
+	unsigned int			count)
+{
+	return xfs_trans_get_rud(tp, intent);
+}
+
+/* Process a deferred rmap update. */
+STATIC int
+xfs_rmap_update_finish_item(
+	struct xfs_trans		*tp,
+	struct xfs_defer_ops		*dop,
+	struct list_head		*item,
+	void				*done_item,
+	void				**state)
+{
+	struct xfs_rmap_intent		*rmap;
+	int				error;
+
+	rmap = container_of(item, struct xfs_rmap_intent, ri_list);
+	error = xfs_trans_log_finish_rmap_update(tp, done_item,
+			rmap->ri_type,
+			rmap->ri_owner, rmap->ri_whichfork,
+			rmap->ri_bmap.br_startoff,
+			rmap->ri_bmap.br_startblock,
+			rmap->ri_bmap.br_blockcount,
+			rmap->ri_bmap.br_state,
+			(struct xfs_btree_cur **)state);
+	kmem_free(rmap);
+	return error;
+}
+
+/* Clean up after processing deferred rmaps. */
+STATIC void
+xfs_rmap_update_finish_cleanup(
+	struct xfs_trans	*tp,
+	void			*state,
+	int			error)
+{
+	struct xfs_btree_cur	*rcur = state;
+
+	xfs_rmap_finish_one_cleanup(tp, rcur, error);
+}
+
+/* Abort all pending RUIs. */
+STATIC void
+xfs_rmap_update_abort_intent(
+	void				*intent)
+{
+	xfs_rui_release(intent);
+}
+
+/* Cancel a deferred rmap update. */
+STATIC void
+xfs_rmap_update_cancel_item(
+	struct list_head		*item)
+{
+	struct xfs_rmap_intent		*rmap;
+
+	rmap = container_of(item, struct xfs_rmap_intent, ri_list);
+	kmem_free(rmap);
+}
+
+static const struct xfs_defer_op_type xfs_rmap_update_defer_type = {
+	.type		= XFS_DEFER_OPS_TYPE_RMAP,
+	.max_items	= XFS_RUI_MAX_FAST_EXTENTS,
+	.diff_items	= xfs_rmap_update_diff_items,
+	.create_intent	= xfs_rmap_update_create_intent,
+	.abort_intent	= xfs_rmap_update_abort_intent,
+	.log_item	= xfs_rmap_update_log_item,
+	.create_done	= xfs_rmap_update_create_done,
+	.finish_item	= xfs_rmap_update_finish_item,
+	.finish_cleanup = xfs_rmap_update_finish_cleanup,
+	.cancel_item	= xfs_rmap_update_cancel_item,
+};
+
+/* Register the deferred op type. */
+void
+xfs_rmap_update_init_defer_op(void)
+{
+	xfs_defer_init_op_type(&xfs_rmap_update_defer_type);
+}