4.9-stable updates for XFS

4.9-stable updates for XFS

[Christoph Hellwig]

Hi all,

below are backports up to 4.14-rc1 for XFS.  I've selected all
clear bugfixes for reported bugs, and a few harmless prep patches
that allow us to carry late bug fixes as-is instead of providing
special versions for -stable, which in the past have caused more
harm than good.

In addition to the patches for 4.13-stable there also are various
patches that are in 4.13 but not in 4.9-stable yet.

[PATCH 01/47] xfs: Move handling of missing page into one place in xfs_find_get_desired_pgoff()

[Christoph Hellwig]

From: Jan Kara <jack@suse.cz>

commit a54fba8f5a0dc36161cacdf2aa90f007f702ec1a upstream.

Currently several places in xfs_find_get_desired_pgoff() handle the case
of a missing page. Make them all handled in one place after the loop has
terminated.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_file.c | 38 ++++++++------------------------------
 1 file changed, 8 insertions(+), 30 deletions(-)

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index df206cfc21f7..2e04b1cdb0d2 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1139,29 +1139,8 @@ xfs_find_get_desired_pgoff(
 		want = min_t(pgoff_t, end - index, PAGEVEC_SIZE - 1) + 1;
 		nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
 					  want);
-		/*
-		 * No page mapped into given range.  If we are searching holes
-		 * and if this is the first time we got into the loop, it means
-		 * that the given offset is landed in a hole, return it.
-		 *
-		 * If we have already stepped through some block buffers to find
-		 * holes but they all contains data.  In this case, the last
-		 * offset is already updated and pointed to the end of the last
-		 * mapped page, if it does not reach the endpoint to search,
-		 * that means there should be a hole between them.
-		 */
-		if (nr_pages == 0) {
-			/* Data search found nothing */
-			if (type == DATA_OFF)
-				break;
-
-			ASSERT(type == HOLE_OFF);
-			if (lastoff == startoff || lastoff < endoff) {
-				found = true;
-				*offset = lastoff;
-			}
+		if (nr_pages == 0)
 			break;
-		}
 
 		for (i = 0; i < nr_pages; i++) {
 			struct page	*page = pvec.pages[i];
@@ -1227,21 +1206,20 @@ xfs_find_get_desired_pgoff(
 
 		/*
 		 * The number of returned pages less than our desired, search
-		 * done.  In this case, nothing was found for searching data,
-		 * but we found a hole behind the last offset.
+		 * done.
 		 */
-		if (nr_pages < want) {
-			if (type == HOLE_OFF) {
-				*offset = lastoff;
-				found = true;
-			}
+		if (nr_pages < want)
 			break;
-		}
 
 		index = pvec.pages[i - 1]->index + 1;
 		pagevec_release(&pvec);
 	} while (index <= end);
 
+	/* No page at lastoff and we are not done - we found a hole. */
+	if (type == HOLE_OFF && lastoff < endoff) {
+		*offset = lastoff;
+		found = true;
+	}
 out:
 	pagevec_release(&pvec);
 	return found;
-- 
2.14.1

[PATCH 02/47] xfs: fix spurious spin_is_locked() assert failures on non-smp kernels

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 95989c46d2a156365867b1d795fdefce71bce378 upstream.

The 0-day kernel test robot reports assertion failures on
!CONFIG_SMP kernels due to failed spin_is_locked() checks. As it
turns out, spin_is_locked() is hardcoded to return zero on
!CONFIG_SMP kernels and so this function cannot be relied on to
verify spinlock state in this configuration.

To avoid this problem, replace the associated asserts with lockdep
variants that do the right thing regardless of kernel configuration.
Drop the one assert that checks for an unlocked lock as there is no
suitable lockdep variant for that case. This moves the spinlock
checks from XFS debug code to lockdep, but generally provides the
same level of protection.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf.c    | 2 +-
 fs/xfs/xfs_icache.c | 5 ++---
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 16269271ebd6..24940dd3baa8 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -116,7 +116,7 @@ static inline void
 __xfs_buf_ioacct_dec(
 	struct xfs_buf	*bp)
 {
-	ASSERT(spin_is_locked(&bp->b_lock));
+	lockdep_assert_held(&bp->b_lock);
 
 	if (bp->b_state & XFS_BSTATE_IN_FLIGHT) {
 		bp->b_state &= ~XFS_BSTATE_IN_FLIGHT;
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 74304b6ce84b..e279882de427 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -66,7 +66,6 @@ xfs_inode_alloc(
 
 	XFS_STATS_INC(mp, vn_active);
 	ASSERT(atomic_read(&ip->i_pincount) == 0);
-	ASSERT(!spin_is_locked(&ip->i_flags_lock));
 	ASSERT(!xfs_isiflocked(ip));
 	ASSERT(ip->i_ino == 0);
 
@@ -192,7 +191,7 @@ xfs_perag_set_reclaim_tag(
 {
 	struct xfs_mount	*mp = pag->pag_mount;
 
-	ASSERT(spin_is_locked(&pag->pag_ici_lock));
+	lockdep_assert_held(&pag->pag_ici_lock);
 	if (pag->pag_ici_reclaimable++)
 		return;
 
@@ -214,7 +213,7 @@ xfs_perag_clear_reclaim_tag(
 {
 	struct xfs_mount	*mp = pag->pag_mount;
 
-	ASSERT(spin_is_locked(&pag->pag_ici_lock));
+	lockdep_assert_held(&pag->pag_ici_lock);
 	if (--pag->pag_ici_reclaimable)
 		return;
 
-- 
2.14.1

[PATCH 03/47] xfs: push buffer of flush locked dquot to avoid quotacheck deadlock

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 7912e7fef2aebe577f0b46d3cba261f2783c5695 upstream.

Reclaim during quotacheck can lead to deadlocks on the dquot flush
lock:

 - Quotacheck populates a local delwri queue with the physical dquot
   buffers.
 - Quotacheck performs the xfs_qm_dqusage_adjust() bulkstat and
   dirties all of the dquots.
 - Reclaim kicks in and attempts to flush a dquot whose buffer is
   already queud on the quotacheck queue. The flush succeeds but
   queueing to the reclaim delwri queue fails as the backing buffer is
   already queued. The flush unlock is now deferred to I/O completion
   of the buffer from the quotacheck queue.
 - The dqadjust bulkstat continues and dirties the recently flushed
   dquot once again.
 - Quotacheck proceeds to the xfs_qm_flush_one() walk which requires
   the flush lock to update the backing buffers with the in-core
   recalculated values. It deadlocks on the redirtied dquot as the
   flush lock was already acquired by reclaim, but the buffer resides
   on the local delwri queue which isn't submitted until the end of
   quotacheck.

This is reproduced by running quotacheck on a filesystem with a
couple million inodes in low memory (512MB-1GB) situations. This is
a regression as of commit 43ff2122e6 ("xfs: on-stack delayed write
buffer lists"), which removed a trylock and buffer I/O submission
from the quotacheck dquot flush sequence.

Quotacheck first resets and collects the physical dquot buffers in a
delwri queue. Then, it traverses the filesystem inodes via bulkstat,
updates the in-core dquots, flushes the corrected dquots to the
backing buffers and finally submits the delwri queue for I/O. Since
the backing buffers are queued across the entire quotacheck
operation, dquot reclaim cannot possibly complete a dquot flush
before quotacheck completes.

Therefore, quotacheck must submit the buffer for I/O in order to
cycle the flush lock and flush the dirty in-core dquot to the
buffer. Add a delwri queue buffer push mechanism to submit an
individual buffer for I/O without losing the delwri queue status and
use it from quotacheck to avoid the deadlock. This restores
quotacheck behavior to as before the regression was introduced.

Reported-by: Martin Svec <martin.svec@zoner.cz>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf.c   | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 fs/xfs/xfs_buf.h   |  1 +
 fs/xfs/xfs_qm.c    | 28 ++++++++++++++++++++++++-
 fs/xfs/xfs_trace.h |  1 +
 4 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 24940dd3baa8..eca7baecc9f0 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -2022,6 +2022,66 @@ xfs_buf_delwri_submit(
 	return error;
 }
 
+/*
+ * Push a single buffer on a delwri queue.
+ *
+ * The purpose of this function is to submit a single buffer of a delwri queue
+ * and return with the buffer still on the original queue. The waiting delwri
+ * buffer submission infrastructure guarantees transfer of the delwri queue
+ * buffer reference to a temporary wait list. We reuse this infrastructure to
+ * transfer the buffer back to the original queue.
+ *
+ * Note the buffer transitions from the queued state, to the submitted and wait
+ * listed state and back to the queued state during this call. The buffer
+ * locking and queue management logic between _delwri_pushbuf() and
+ * _delwri_queue() guarantee that the buffer cannot be queued to another list
+ * before returning.
+ */
+int
+xfs_buf_delwri_pushbuf(
+	struct xfs_buf		*bp,
+	struct list_head	*buffer_list)
+{
+	LIST_HEAD		(submit_list);
+	int			error;
+
+	ASSERT(bp->b_flags & _XBF_DELWRI_Q);
+
+	trace_xfs_buf_delwri_pushbuf(bp, _RET_IP_);
+
+	/*
+	 * Isolate the buffer to a new local list so we can submit it for I/O
+	 * independently from the rest of the original list.
+	 */
+	xfs_buf_lock(bp);
+	list_move(&bp->b_list, &submit_list);
+	xfs_buf_unlock(bp);
+
+	/*
+	 * Delwri submission clears the DELWRI_Q buffer flag and returns with
+	 * the buffer on the wait list with an associated reference. Rather than
+	 * bounce the buffer from a local wait list back to the original list
+	 * after I/O completion, reuse the original list as the wait list.
+	 */
+	xfs_buf_delwri_submit_buffers(&submit_list, buffer_list);
+
+	/*
+	 * The buffer is now under I/O and wait listed as during typical delwri
+	 * submission. Lock the buffer to wait for I/O completion. Rather than
+	 * remove the buffer from the wait list and release the reference, we
+	 * want to return with the buffer queued to the original list. The
+	 * buffer already sits on the original list with a wait list reference,
+	 * however. If we let the queue inherit that wait list reference, all we
+	 * need to do is reset the DELWRI_Q flag.
+	 */
+	xfs_buf_lock(bp);
+	error = bp->b_error;
+	bp->b_flags |= _XBF_DELWRI_Q;
+	xfs_buf_unlock(bp);
+
+	return error;
+}
+
 int __init
 xfs_buf_init(void)
 {
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index ad514a8025dd..f961b19b9cc2 100644
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -333,6 +333,7 @@ extern void xfs_buf_delwri_cancel(struct list_head *);
 extern bool xfs_buf_delwri_queue(struct xfs_buf *, struct list_head *);
 extern int xfs_buf_delwri_submit(struct list_head *);
 extern int xfs_buf_delwri_submit_nowait(struct list_head *);
+extern int xfs_buf_delwri_pushbuf(struct xfs_buf *, struct list_head *);
 
 /* Buffer Daemon Setup Routines */
 extern int xfs_buf_init(void);
diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index 8b9a9f15f022..8068867a8183 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -1247,6 +1247,7 @@ xfs_qm_flush_one(
 	struct xfs_dquot	*dqp,
 	void			*data)
 {
+	struct xfs_mount	*mp = dqp->q_mount;
 	struct list_head	*buffer_list = data;
 	struct xfs_buf		*bp = NULL;
 	int			error = 0;
@@ -1257,7 +1258,32 @@ xfs_qm_flush_one(
 	if (!XFS_DQ_IS_DIRTY(dqp))
 		goto out_unlock;
 
-	xfs_dqflock(dqp);
+	/*
+	 * The only way the dquot is already flush locked by the time quotacheck
+	 * gets here is if reclaim flushed it before the dqadjust walk dirtied
+	 * it for the final time. Quotacheck collects all dquot bufs in the
+	 * local delwri queue before dquots are dirtied, so reclaim can't have
+	 * possibly queued it for I/O. The only way out is to push the buffer to
+	 * cycle the flush lock.
+	 */
+	if (!xfs_dqflock_nowait(dqp)) {
+		/* buf is pinned in-core by delwri list */
+		DEFINE_SINGLE_BUF_MAP(map, dqp->q_blkno,
+				      mp->m_quotainfo->qi_dqchunklen);
+		bp = _xfs_buf_find(mp->m_ddev_targp, &map, 1, 0, NULL);
+		if (!bp) {
+			error = -EINVAL;
+			goto out_unlock;
+		}
+		xfs_buf_unlock(bp);
+
+		xfs_buf_delwri_pushbuf(bp, buffer_list);
+		xfs_buf_rele(bp);
+
+		error = -EAGAIN;
+		goto out_unlock;
+	}
+
 	error = xfs_qm_dqflush(dqp, &bp);
 	if (error)
 		goto out_unlock;
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 828f383df121..2df73f3a73c1 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -366,6 +366,7 @@ DEFINE_BUF_EVENT(xfs_buf_iowait_done);
 DEFINE_BUF_EVENT(xfs_buf_delwri_queue);
 DEFINE_BUF_EVENT(xfs_buf_delwri_queued);
 DEFINE_BUF_EVENT(xfs_buf_delwri_split);
+DEFINE_BUF_EVENT(xfs_buf_delwri_pushbuf);
 DEFINE_BUF_EVENT(xfs_buf_get_uncached);
 DEFINE_BUF_EVENT(xfs_bdstrat_shut);
 DEFINE_BUF_EVENT(xfs_buf_item_relse);
-- 
2.14.1

[PATCH 04/47] xfs: try to avoid blowing out the transaction reservation when bunmaping a shared extent

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit e1a4e37cc7b665b6804fba812aca2f4d7402c249 upstream.

In a pathological scenario where we are trying to bunmapi a single
extent in which every other block is shared, it's possible that trying
to unmap the entire large extent in a single transaction can generate so
many EFIs that we overflow the transaction reservation.

Therefore, use a heuristic to guess at the number of blocks we can
safely unmap from a reflink file's data fork in an single transaction.
This should prevent problems such as the log head slamming into the tail
and ASSERTs that trigger because we've exceeded the transaction
reservation.

Note that since bunmapi can fail to unmap the entire range, we must also
teach the deferred unmap code to roll into a new transaction whenever we
get low on reservation.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[hch: random edits, all bugs are my fault]
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/libxfs/xfs_bmap.c     | 37 ++++++++++++++++++++++++++++---------
 fs/xfs/libxfs/xfs_bmap.h     |  2 +-
 fs/xfs/libxfs/xfs_refcount.c | 10 +---------
 fs/xfs/libxfs/xfs_refcount.h | 16 ++++++++++++++++
 fs/xfs/xfs_bmap_item.c       | 17 +++++++++++++++--
 fs/xfs/xfs_trans.h           |  2 +-
 fs/xfs/xfs_trans_bmap.c      | 11 +++++++++--
 7 files changed, 71 insertions(+), 24 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 2a8cbd15d5d1..b79719a87638 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -5555,6 +5555,7 @@ __xfs_bunmapi(
 	int			whichfork;	/* data or attribute fork */
 	xfs_fsblock_t		sum;
 	xfs_filblks_t		len = *rlen;	/* length to unmap in file */
+	xfs_fileoff_t		max_len;
 
 	trace_xfs_bunmap(ip, bno, len, flags, _RET_IP_);
 
@@ -5576,6 +5577,16 @@ __xfs_bunmapi(
 	ASSERT(len > 0);
 	ASSERT(nexts >= 0);
 
+	/*
+	 * Guesstimate how many blocks we can unmap without running the risk of
+	 * blowing out the transaction with a mix of EFIs and reflink
+	 * adjustments.
+	 */
+	if (xfs_is_reflink_inode(ip) && whichfork == XFS_DATA_FORK)
+		max_len = min(len, xfs_refcount_max_unmap(tp->t_log_res));
+	else
+		max_len = len;
+
 	if (!(ifp->if_flags & XFS_IFEXTENTS) &&
 	    (error = xfs_iread_extents(tp, ip, whichfork)))
 		return error;
@@ -5621,7 +5632,7 @@ __xfs_bunmapi(
 
 	extno = 0;
 	while (bno != (xfs_fileoff_t)-1 && bno >= start && lastx >= 0 &&
-	       (nexts == 0 || extno < nexts)) {
+	       (nexts == 0 || extno < nexts) && max_len > 0) {
 		/*
 		 * Is the found extent after a hole in which bno lives?
 		 * Just back up to the previous extent, if so.
@@ -5655,6 +5666,15 @@ __xfs_bunmapi(
 		}
 		if (del.br_startoff + del.br_blockcount > bno + 1)
 			del.br_blockcount = bno + 1 - del.br_startoff;
+
+		/* How much can we safely unmap? */
+		if (max_len < del.br_blockcount) {
+			del.br_startoff += del.br_blockcount - max_len;
+			if (!wasdel)
+				del.br_startblock += del.br_blockcount - max_len;
+			del.br_blockcount = max_len;
+		}
+
 		sum = del.br_startblock + del.br_blockcount;
 		if (isrt &&
 		    (mod = do_mod(sum, mp->m_sb.sb_rextsize))) {
@@ -5835,6 +5855,7 @@ __xfs_bunmapi(
 		if (!isrt && wasdel)
 			xfs_mod_fdblocks(mp, (int64_t)del.br_blockcount, false);
 
+		max_len -= del.br_blockcount;
 		bno = del.br_startoff - 1;
 nodelete:
 		/*
@@ -6604,25 +6625,24 @@ xfs_bmap_finish_one(
 	int				whichfork,
 	xfs_fileoff_t			startoff,
 	xfs_fsblock_t			startblock,
-	xfs_filblks_t			blockcount,
+	xfs_filblks_t			*blockcount,
 	xfs_exntst_t			state)
 {
 	struct xfs_bmbt_irec		bmap;
 	int				nimaps = 1;
 	xfs_fsblock_t			firstfsb;
 	int				flags = XFS_BMAPI_REMAP;
-	int				done;
 	int				error = 0;
 
 	bmap.br_startblock = startblock;
 	bmap.br_startoff = startoff;
-	bmap.br_blockcount = blockcount;
+	bmap.br_blockcount = *blockcount;
 	bmap.br_state = state;
 
 	trace_xfs_bmap_deferred(tp->t_mountp,
 			XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
 			XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
-			ip->i_ino, whichfork, startoff, blockcount, state);
+			ip->i_ino, whichfork, startoff, *blockcount, state);
 
 	if (whichfork != XFS_DATA_FORK && whichfork != XFS_ATTR_FORK)
 		return -EFSCORRUPTED;
@@ -6641,12 +6661,11 @@ xfs_bmap_finish_one(
 					bmap.br_blockcount, flags, &firstfsb,
 					bmap.br_blockcount, &bmap, &nimaps,
 					dfops);
+		*blockcount = 0;
 		break;
 	case XFS_BMAP_UNMAP:
-		error = xfs_bunmapi(tp, ip, bmap.br_startoff,
-				bmap.br_blockcount, flags, 1, &firstfsb,
-				dfops, &done);
-		ASSERT(done);
+		error = __xfs_bunmapi(tp, ip, startoff, blockcount,
+				XFS_BMAPI_REMAP, 1, &firstfsb, dfops);
 		break;
 	default:
 		ASSERT(0);
diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h
index e7d40b39f18f..db53ac7ff6df 100644
--- a/fs/xfs/libxfs/xfs_bmap.h
+++ b/fs/xfs/libxfs/xfs_bmap.h
@@ -265,7 +265,7 @@ struct xfs_bmap_intent {
 int	xfs_bmap_finish_one(struct xfs_trans *tp, struct xfs_defer_ops *dfops,
 		struct xfs_inode *ip, enum xfs_bmap_intent_type type,
 		int whichfork, xfs_fileoff_t startoff, xfs_fsblock_t startblock,
-		xfs_filblks_t blockcount, xfs_exntst_t state);
+		xfs_filblks_t *blockcount, xfs_exntst_t state);
 int	xfs_bmap_map_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
 		struct xfs_inode *ip, struct xfs_bmbt_irec *imap);
 int	xfs_bmap_unmap_extent(struct xfs_mount *mp, struct xfs_defer_ops *dfops,
diff --git a/fs/xfs/libxfs/xfs_refcount.c b/fs/xfs/libxfs/xfs_refcount.c
index 82a38d86ebad..e17016163542 100644
--- a/fs/xfs/libxfs/xfs_refcount.c
+++ b/fs/xfs/libxfs/xfs_refcount.c
@@ -784,14 +784,6 @@ xfs_refcount_merge_extents(
 }
 
 /*
- * While we're adjusting the refcounts records of an extent, we have
- * to keep an eye on the number of extents we're dirtying -- run too
- * many in a single transaction and we'll exceed the transaction's
- * reservation and crash the fs.  Each record adds 12 bytes to the
- * log (plus any key updates) so we'll conservatively assume 24 bytes
- * per record.  We must also leave space for btree splits on both ends
- * of the range and space for the CUD and a new CUI.
- *
  * XXX: This is a pretty hand-wavy estimate.  The penalty for guessing
  * true incorrectly is a shutdown FS; the penalty for guessing false
  * incorrectly is more transaction rolls than might be necessary.
@@ -822,7 +814,7 @@ xfs_refcount_still_have_space(
 	else if (overhead > cur->bc_tp->t_log_res)
 		return false;
 	return  cur->bc_tp->t_log_res - overhead >
-		cur->bc_private.a.priv.refc.nr_ops * 32;
+		cur->bc_private.a.priv.refc.nr_ops * XFS_REFCOUNT_ITEM_OVERHEAD;
 }
 
 /*
diff --git a/fs/xfs/libxfs/xfs_refcount.h b/fs/xfs/libxfs/xfs_refcount.h
index 098dc668ab2c..eafb9d1f3b37 100644
--- a/fs/xfs/libxfs/xfs_refcount.h
+++ b/fs/xfs/libxfs/xfs_refcount.h
@@ -67,4 +67,20 @@ extern int xfs_refcount_free_cow_extent(struct xfs_mount *mp,
 extern int xfs_refcount_recover_cow_leftovers(struct xfs_mount *mp,
 		xfs_agnumber_t agno);
 
+/*
+ * While we're adjusting the refcounts records of an extent, we have
+ * to keep an eye on the number of extents we're dirtying -- run too
+ * many in a single transaction and we'll exceed the transaction's
+ * reservation and crash the fs.  Each record adds 12 bytes to the
+ * log (plus any key updates) so we'll conservatively assume 32 bytes
+ * per record.  We must also leave space for btree splits on both ends
+ * of the range and space for the CUD and a new CUI.
+ */
+#define XFS_REFCOUNT_ITEM_OVERHEAD	32
+
+static inline xfs_fileoff_t xfs_refcount_max_unmap(int log_res)
+{
+	return (log_res * 3 / 4) / XFS_REFCOUNT_ITEM_OVERHEAD;
+}
+
 #endif	/* __XFS_REFCOUNT_H__ */
diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c
index c4b90e794e41..5a54dcd7e7b1 100644
--- a/fs/xfs/xfs_bmap_item.c
+++ b/fs/xfs/xfs_bmap_item.c
@@ -395,6 +395,7 @@ xfs_bui_recover(
 	struct xfs_map_extent		*bmap;
 	xfs_fsblock_t			startblock_fsb;
 	xfs_fsblock_t			inode_fsb;
+	xfs_filblks_t			count;
 	bool				op_ok;
 	struct xfs_bud_log_item		*budp;
 	enum xfs_bmap_intent_type	type;
@@ -403,6 +404,7 @@ xfs_bui_recover(
 	struct xfs_trans		*tp;
 	struct xfs_inode		*ip = NULL;
 	struct xfs_defer_ops		dfops;
+	struct xfs_bmbt_irec		irec;
 	xfs_fsblock_t			firstfsb;
 
 	ASSERT(!test_bit(XFS_BUI_RECOVERED, &buip->bui_flags));
@@ -480,13 +482,24 @@ xfs_bui_recover(
 	}
 	xfs_trans_ijoin(tp, ip, 0);
 
+	count = bmap->me_len;
 	error = xfs_trans_log_finish_bmap_update(tp, budp, &dfops, type,
 			ip, whichfork, bmap->me_startoff,
-			bmap->me_startblock, bmap->me_len,
-			state);
+			bmap->me_startblock, &count, state);
 	if (error)
 		goto err_dfops;
 
+	if (count > 0) {
+		ASSERT(type == XFS_BMAP_UNMAP);
+		irec.br_startblock = bmap->me_startblock;
+		irec.br_blockcount = count;
+		irec.br_startoff = bmap->me_startoff;
+		irec.br_state = state;
+		error = xfs_bmap_unmap_extent(tp->t_mountp, &dfops, ip, &irec);
+		if (error)
+			goto err_dfops;
+	}
+
 	/* Finish transaction, free inodes. */
 	error = xfs_defer_finish(&tp, &dfops, NULL);
 	if (error)
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 98024cb933ef..c0e72ab57741 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -277,6 +277,6 @@ int xfs_trans_log_finish_bmap_update(struct xfs_trans *tp,
 		struct xfs_bud_log_item *rudp, struct xfs_defer_ops *dfops,
 		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);
+		xfs_filblks_t *blockcount, xfs_exntst_t state);
 
 #endif	/* __XFS_TRANS_H__ */
diff --git a/fs/xfs/xfs_trans_bmap.c b/fs/xfs/xfs_trans_bmap.c
index 6408e7d7c08c..14543d93cd4b 100644
--- a/fs/xfs/xfs_trans_bmap.c
+++ b/fs/xfs/xfs_trans_bmap.c
@@ -63,7 +63,7 @@ xfs_trans_log_finish_bmap_update(
 	int				whichfork,
 	xfs_fileoff_t			startoff,
 	xfs_fsblock_t			startblock,
-	xfs_filblks_t			blockcount,
+	xfs_filblks_t			*blockcount,
 	xfs_exntst_t			state)
 {
 	int				error;
@@ -196,16 +196,23 @@ xfs_bmap_update_finish_item(
 	void				**state)
 {
 	struct xfs_bmap_intent		*bmap;
+	xfs_filblks_t			count;
 	int				error;
 
 	bmap = container_of(item, struct xfs_bmap_intent, bi_list);
+	count = bmap->bi_bmap.br_blockcount;
 	error = xfs_trans_log_finish_bmap_update(tp, done_item, dop,
 			bmap->bi_type,
 			bmap->bi_owner, bmap->bi_whichfork,
 			bmap->bi_bmap.br_startoff,
 			bmap->bi_bmap.br_startblock,
-			bmap->bi_bmap.br_blockcount,
+			&count,
 			bmap->bi_bmap.br_state);
+	if (!error && count > 0) {
+		ASSERT(bmap->bi_type == XFS_BMAP_UNMAP);
+		bmap->bi_bmap.br_blockcount = count;
+		return -EAGAIN;
+	}
 	kmem_free(bmap);
 	return error;
 }
-- 
2.14.1

[PATCH 05/47] xfs: release bli from transaction properly on fs shutdown

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 79e641ce29cfae5b8fc55fb77ac62d11d2d849c0 upstream.

If a filesystem shutdown occurs with a buffer log item in the CIL
and a log force occurs, the ->iop_unpin() handler is generally
expected to tear down the bli properly. This entails freeing the bli
memory and releasing the associated hold on the buffer so it can be
released and the filesystem unmounted.

If this sequence occurs while ->bli_refcount is elevated (i.e.,
another transaction is open and attempting to modify the buffer),
however, ->iop_unpin() may not be responsible for releasing the bli.
Instead, the transaction may release the final ->bli_refcount
reference and thus xfs_trans_brelse() is responsible for tearing
down the bli.

While xfs_trans_brelse() does drop the reference count, it only
attempts to release the bli if it is clean (i.e., not in the
CIL/AIL). If the filesystem is shutdown and the bli is sitting dirty
in the CIL as noted above, this ends up skipping the last
opportunity to release the bli. In turn, this leaves the hold on the
buffer and causes an unmount hang. This can be reproduced by running
generic/388 in repetition.

Update xfs_trans_brelse() to handle this shutdown corner case
correctly. If the final bli reference is dropped and the filesystem
is shutdown, remove the bli from the AIL (if necessary) and release
the bli to drop the buffer hold and ensure an unmount does not hang.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_trans_buf.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index 8ee29ca132dc..86987d823d76 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -356,6 +356,7 @@ xfs_trans_brelse(xfs_trans_t	*tp,
 		 xfs_buf_t	*bp)
 {
 	xfs_buf_log_item_t	*bip;
+	int			freed;
 
 	/*
 	 * Default to a normal brelse() call if the tp is NULL.
@@ -419,16 +420,22 @@ xfs_trans_brelse(xfs_trans_t	*tp,
 	/*
 	 * Drop our reference to the buf log item.
 	 */
-	atomic_dec(&bip->bli_refcount);
+	freed = atomic_dec_and_test(&bip->bli_refcount);
 
 	/*
-	 * If the buf item is not tracking data in the log, then
-	 * we must free it before releasing the buffer back to the
-	 * free pool.  Before releasing the buffer to the free pool,
-	 * clear the transaction pointer in b_fsprivate2 to dissolve
-	 * its relation to this transaction.
+	 * If the buf item is not tracking data in the log, then we must free it
+	 * before releasing the buffer back to the free pool.
+	 *
+	 * If the fs has shutdown and we dropped the last reference, it may fall
+	 * on us to release a (possibly dirty) bli if it never made it to the
+	 * AIL (e.g., the aborted unpin already happened and didn't release it
+	 * due to our reference). Since we're already shutdown and need xa_lock,
+	 * just force remove from the AIL and release the bli here.
 	 */
-	if (!xfs_buf_item_dirty(bip)) {
+	if (XFS_FORCED_SHUTDOWN(tp->t_mountp) && freed) {
+		xfs_trans_ail_remove(&bip->bli_item, SHUTDOWN_LOG_IO_ERROR);
+		xfs_buf_item_relse(bp);
+	} else if (!xfs_buf_item_dirty(bip)) {
 /***
 		ASSERT(bp->b_pincount == 0);
 ***/
-- 
2.14.1

[PATCH 06/47] xfs: remove bli from AIL before release on transaction abort

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 3d4b4a3e30ae7a949c31e1e10268a3da4723d290 upstream.

When a buffer is modified, logged and committed, it ultimately ends
up sitting on the AIL with a dirty bli waiting for metadata
writeback. If another transaction locks and invalidates the buffer
(freeing an inode chunk, for example) in the meantime, the bli is
flagged as stale, the dirty state is cleared and the bli remains in
the AIL.

If a shutdown occurs before the transaction that has invalidated the
buffer is committed, the transaction is ultimately aborted. The log
items are flagged as such and ->iop_unlock() handles the aborted
items. Because the bli is clean (due to the invalidation),
->iop_unlock() unconditionally releases it. The log item may still
reside in the AIL, however, which means the I/O completion handler
may still run and attempt to access it. This results in assert
failure due to the release of the bli while still present in the AIL
and a subsequent NULL dereference and panic in the buffer I/O
completion handling. This can be reproduced by running generic/388
in repetition.

To avoid this problem, update xfs_buf_item_unlock() to first check
whether the bli is aborted and if so, remove it from the AIL before
it is released. This ensures that the bli is no longer accessed
during the shutdown sequence after it has been freed.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf_item.c | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 0306168af332..f6a8422e9562 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -636,20 +636,23 @@ xfs_buf_item_unlock(
 
 	/*
 	 * Clean buffers, by definition, cannot be in the AIL. However, aborted
-	 * buffers may be dirty and hence in the AIL. Therefore if we are
-	 * aborting a buffer and we've just taken the last refernce away, we
-	 * have to check if it is in the AIL before freeing it. We need to free
-	 * it in this case, because an aborted transaction has already shut the
-	 * filesystem down and this is the last chance we will have to do so.
+	 * buffers may be in the AIL regardless of dirty state. An aborted
+	 * transaction that invalidates a buffer already in the AIL may have
+	 * marked it stale and cleared the dirty state, for example.
+	 *
+	 * Therefore if we are aborting a buffer and we've just taken the last
+	 * reference away, we have to check if it is in the AIL before freeing
+	 * it. We need to free it in this case, because an aborted transaction
+	 * has already shut the filesystem down and this is the last chance we
+	 * will have to do so.
 	 */
 	if (atomic_dec_and_test(&bip->bli_refcount)) {
-		if (clean)
-			xfs_buf_item_relse(bp);
-		else if (aborted) {
+		if (aborted) {
 			ASSERT(XFS_FORCED_SHUTDOWN(lip->li_mountp));
 			xfs_trans_ail_remove(lip, SHUTDOWN_LOG_IO_ERROR);
 			xfs_buf_item_relse(bp);
-		}
+		} else if (clean)
+			xfs_buf_item_relse(bp);
 	}
 
 	if (!(flags & XFS_BLI_HOLD))
-- 
2.14.1

[PATCH 07/47] xfs: don't allow bmap on rt files

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit 61d819e7bcb7f33da710bf3f5dcb2bcf1e48203c upstream.

bmap returns a dumb LBA address but not the block device that goes with
that LBA.  Swapfiles don't care about this and will blindly assume that
the data volume is the correct blockdev, which is totally bogus for
files on the rt subvolume.  This results in the swap code doing IOs to
arbitrary locations on the data device(!) if the passed in mapping is a
realtime file, so just turn off bmap for rt files.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_aops.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 578981412615..f750d888bd17 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -1566,9 +1566,12 @@ xfs_vm_bmap(
 	 * The swap code (ab-)uses ->bmap to get a block mapping and then
 	 * bypasseѕ the file system for actual I/O.  We really can't allow
 	 * that on reflinks inodes, so we have to skip out here.  And yes,
-	 * 0 is the magic code for a bmap error..
+	 * 0 is the magic code for a bmap error.
+	 *
+	 * Since we don't pass back blockdev info, we can't return bmap
+	 * information for rt files either.
 	 */
-	if (xfs_is_reflink_inode(ip)) {
+	if (xfs_is_reflink_inode(ip) || XFS_IS_REALTIME_INODE(ip)) {
 		xfs_iunlock(ip, XFS_IOLOCK_SHARED);
 		return 0;
 	}
-- 
2.14.1

[PATCH 08/47] xfs: free uncommitted transactions during log recovery

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 39775431f82f890f4aaa08860a30883d081bffc7 upstream.

Log recovery allocates in-core transaction and member item data
structures on-demand as it processes the on-disk log. Transactions
are allocated on first encounter on-disk and stored in a hash table
structure where they are easily accessible for subsequent lookups.
Transaction items are also allocated on demand and are attached to
the associated transactions.

When a commit record is encountered in the log, the transaction is
committed to the fs and the in-core structures are freed. If a
filesystem crashes or shuts down before all in-core log buffers are
flushed to the log, however, not all transactions may have commit
records in the log. As expected, the modifications in such an
incomplete transaction are not replayed to the fs. The in-core data
structures for the partial transaction are never freed, however,
resulting in a memory leak.

Update xlog_do_recovery_pass() to first correctly initialize the
hash table array so empty lists can be distinguished from populated
lists on function exit. Update xlog_recover_free_trans() to always
remove the transaction from the list prior to freeing the associated
memory. Finally, walk the hash table of transaction lists as the
last step before it goes out of scope and free any transactions that
may remain on the lists. This prevents a memory leak of partial
transactions in the log.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log_recover.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 9b3d7c76915d..e06aa2827ecb 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -4152,7 +4152,7 @@ xlog_recover_commit_trans(
 
 	#define XLOG_RECOVER_COMMIT_QUEUE_MAX 100
 
-	hlist_del(&trans->r_list);
+	hlist_del_init(&trans->r_list);
 
 	error = xlog_recover_reorder_trans(log, trans, pass);
 	if (error)
@@ -4354,6 +4354,8 @@ xlog_recover_free_trans(
 	xlog_recover_item_t	*item, *n;
 	int			i;
 
+	hlist_del_init(&trans->r_list);
+
 	list_for_each_entry_safe(item, n, &trans->r_itemq, ri_list) {
 		/* Free the regions in the item. */
 		list_del(&item->ri_list);
@@ -5222,12 +5224,16 @@ xlog_do_recovery_pass(
 	int			error2 = 0;
 	int			bblks, split_bblks;
 	int			hblks, split_hblks, wrapped_hblks;
+	int			i;
 	struct hlist_head	rhash[XLOG_RHASH_SIZE];
 	LIST_HEAD		(buffer_list);
 
 	ASSERT(head_blk != tail_blk);
 	rhead_blk = 0;
 
+	for (i = 0; i < XLOG_RHASH_SIZE; i++)
+		INIT_HLIST_HEAD(&rhash[i]);
+
 	/*
 	 * Read the header of the tail block and get the iclog buffer size from
 	 * h_size.  Use this to tell how many sectors make up the log header.
@@ -5464,6 +5470,19 @@ xlog_do_recovery_pass(
 	if (error && first_bad)
 		*first_bad = rhead_blk;
 
+	/*
+	 * Transactions are freed at commit time but transactions without commit
+	 * records on disk are never committed. Free any that may be left in the
+	 * hash table.
+	 */
+	for (i = 0; i < XLOG_RHASH_SIZE; i++) {
+		struct hlist_node	*tmp;
+		struct xlog_recover	*trans;
+
+		hlist_for_each_entry_safe(trans, tmp, &rhash[i], r_list)
+			xlog_recover_free_trans(trans);
+	}
+
 	return error ? error : error2;
 }
 
-- 
2.14.1

[PATCH 09/47] xfs: free cowblocks and retry on buffered write ENOSPC

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit cf2cb7845d6e101cb17bd62f8aa08cd514fc8988 upstream.

XFS runs an eofblocks reclaim scan before returning an ENOSPC error to
userspace for buffered writes. This facilitates aggressive speculative
preallocation without causing user visible side effects such as
premature ENOSPC.

Run a cowblocks scan in the same situation to reclaim lingering COW fork
preallocation throughout the filesystem.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_file.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 2e04b1cdb0d2..586b398f268d 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -729,6 +729,7 @@ xfs_file_buffered_aio_write(
 		xfs_rw_iunlock(ip, iolock);
 		eofb.eof_flags = XFS_EOF_FLAGS_SYNC;
 		xfs_icache_free_eofblocks(ip->i_mount, &eofb);
+		xfs_icache_free_cowblocks(ip->i_mount, &eofb);
 		goto write_retry;
 	}
 
-- 
2.14.1

[PATCH 10/47] xfs: don't crash on unexpected holes in dir/attr btrees

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit cd87d867920155911d0d2e6485b769d853547750 upstream.

In quite a few places we call xfs_da_read_buf with a mappedbno that we
don't control, then assume that the function passes back either an error
code or a buffer pointer.  Unfortunately, if mappedbno == -2 and bno
maps to a hole, we get a return code of zero and a NULL buffer, which
means that we crash if we actually try to use that buffer pointer.  This
happens immediately when we set the buffer type for transaction context.

Therefore, check that we have no error code and a non-NULL bp before
trying to use bp.  This patch is a follow-up to an incomplete fix in
96a3aefb8ffde231 ("xfs: don't crash if reading a directory results in an
unexpected hole").

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_attr_leaf.c  | 2 +-
 fs/xfs/libxfs/xfs_da_btree.c   | 2 +-
 fs/xfs/libxfs/xfs_dir2_block.c | 2 +-
 fs/xfs/libxfs/xfs_dir2_leaf.c  | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 2852521fc8ec..c6c15e5717e4 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -351,7 +351,7 @@ xfs_attr3_leaf_read(
 
 	err = xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
 				XFS_ATTR_FORK, &xfs_attr3_leaf_buf_ops);
-	if (!err && tp)
+	if (!err && tp && *bpp)
 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_ATTR_LEAF_BUF);
 	return err;
 }
diff --git a/fs/xfs/libxfs/xfs_da_btree.c b/fs/xfs/libxfs/xfs_da_btree.c
index 1bdf2888295b..b305dbfd81c4 100644
--- a/fs/xfs/libxfs/xfs_da_btree.c
+++ b/fs/xfs/libxfs/xfs_da_btree.c
@@ -263,7 +263,7 @@ xfs_da3_node_read(
 
 	err = xfs_da_read_buf(tp, dp, bno, mappedbno, bpp,
 					which_fork, &xfs_da3_node_buf_ops);
-	if (!err && tp) {
+	if (!err && tp && *bpp) {
 		struct xfs_da_blkinfo	*info = (*bpp)->b_addr;
 		int			type;
 
diff --git a/fs/xfs/libxfs/xfs_dir2_block.c b/fs/xfs/libxfs/xfs_dir2_block.c
index aa17cb788946..43c902f7a68d 100644
--- a/fs/xfs/libxfs/xfs_dir2_block.c
+++ b/fs/xfs/libxfs/xfs_dir2_block.c
@@ -139,7 +139,7 @@ xfs_dir3_block_read(
 
 	err = xfs_da_read_buf(tp, dp, mp->m_dir_geo->datablk, -1, bpp,
 				XFS_DATA_FORK, &xfs_dir3_block_buf_ops);
-	if (!err && tp)
+	if (!err && tp && *bpp)
 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_BLOCK_BUF);
 	return err;
 }
diff --git a/fs/xfs/libxfs/xfs_dir2_leaf.c b/fs/xfs/libxfs/xfs_dir2_leaf.c
index b887fb2a2bcf..f2e342e05365 100644
--- a/fs/xfs/libxfs/xfs_dir2_leaf.c
+++ b/fs/xfs/libxfs/xfs_dir2_leaf.c
@@ -268,7 +268,7 @@ xfs_dir3_leaf_read(
 
 	err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 				XFS_DATA_FORK, &xfs_dir3_leaf1_buf_ops);
-	if (!err && tp)
+	if (!err && tp && *bpp)
 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
 	return err;
 }
@@ -285,7 +285,7 @@ xfs_dir3_leafn_read(
 
 	err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
 				XFS_DATA_FORK, &xfs_dir3_leafn_buf_ops);
-	if (!err && tp)
+	if (!err && tp && *bpp)
 		xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
 	return err;
 }
-- 
2.14.1

[PATCH 11/47] xfs: check _btree_check_block value

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit 1e86eabe73b73c82e1110c746ed3ec6d5e1c0a0d upstream.

Check the _btree_check_block return value for the firstrec and lastrec
functions, since we have the ability to signal that the repositioning
did not succeed.

Fixes-coverity-id: 114067
Fixes-coverity-id: 114068
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
 fs/xfs/libxfs/xfs_btree.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 91c68913d495..e9f26a09a0be 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -714,7 +714,8 @@ xfs_btree_firstrec(
 	 * Get the block pointer for this level.
 	 */
 	block = xfs_btree_get_block(cur, level, &bp);
-	xfs_btree_check_block(cur, block, level, bp);
+	if (xfs_btree_check_block(cur, block, level, bp))
+		return 0;
 	/*
 	 * It's empty, there is no such record.
 	 */
@@ -743,7 +744,8 @@ xfs_btree_lastrec(
 	 * Get the block pointer for this level.
 	 */
 	block = xfs_btree_get_block(cur, level, &bp);
-	xfs_btree_check_block(cur, block, level, bp);
+	if (xfs_btree_check_block(cur, block, level, bp))
+		return 0;
 	/*
 	 * It's empty, there is no such record.
 	 */
-- 
2.14.1

[PATCH 12/47] xfs: set firstfsb to NULLFSBLOCK before feeding it to _bmapi_write

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit 4c1a67bd3606540b9b42caff34a1d5cd94b1cf65 upstream.

We must initialize the firstfsb parameter to _bmapi_write so that it
doesn't incorrectly treat stack garbage as a restriction on which AGs
it can search for free space.

Fixes-coverity-id: 1402025
Fixes-coverity-id: 1415167
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
 fs/xfs/libxfs/xfs_bmap.c | 9 +++++++++
 fs/xfs/xfs_reflink.c     | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index b79719a87638..73571fb4dfed 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -6639,6 +6639,15 @@ xfs_bmap_finish_one(
 	bmap.br_blockcount = *blockcount;
 	bmap.br_state = state;
 
+	/*
+	 * firstfsb is tied to the transaction lifetime and is used to
+	 * ensure correct AG locking order and schedule work item
+	 * continuations.  XFS_BUI_MAX_FAST_EXTENTS (== 1) restricts us
+	 * to only making one bmap call per transaction, so it should
+	 * be safe to have it as a local variable here.
+	 */
+	firstfsb = NULLFSBLOCK;
+
 	trace_xfs_bmap_deferred(tp->t_mountp,
 			XFS_FSB_TO_AGNO(tp->t_mountp, startblock), type,
 			XFS_FSB_TO_AGBNO(tp->t_mountp, startblock),
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 29a75ecb2425..350fc64441b1 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -333,7 +333,7 @@ xfs_reflink_convert_cow_extent(
 	struct xfs_defer_ops		*dfops)
 {
 	struct xfs_bmbt_irec		irec = *imap;
-	xfs_fsblock_t			first_block;
+	xfs_fsblock_t			first_block = NULLFSBLOCK;
 	int				nimaps = 1;
 
 	if (imap->br_state == XFS_EXT_NORM)
-- 
2.14.1

[PATCH 13/47] xfs: check _alloc_read_agf buffer pointer before using

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit 10479e2dea83d4c421ad05dfc55d918aa8dfc0cd upstream.

In some circumstances, _alloc_read_agf can return an error code of zero
but also a null AGF buffer pointer.  Check for this and jump out.

Fixes-coverity-id: 1415250
Fixes-coverity-id: 1415320
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
 fs/xfs/libxfs/xfs_refcount.c | 4 ++++
 fs/xfs/xfs_reflink.c         | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/fs/xfs/libxfs/xfs_refcount.c b/fs/xfs/libxfs/xfs_refcount.c
index e17016163542..d71cb63cdea3 100644
--- a/fs/xfs/libxfs/xfs_refcount.c
+++ b/fs/xfs/libxfs/xfs_refcount.c
@@ -1640,6 +1640,10 @@ xfs_refcount_recover_cow_leftovers(
 	error = xfs_alloc_read_agf(mp, tp, agno, 0, &agbp);
 	if (error)
 		goto out_trans;
+	if (!agbp) {
+		error = -ENOMEM;
+		goto out_trans;
+	}
 	cur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno, NULL);
 
 	/* Find all the leftover CoW staging extents. */
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 350fc64441b1..0015c19c7455 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -169,6 +169,8 @@ xfs_reflink_find_shared(
 	error = xfs_alloc_read_agf(mp, NULL, agno, 0, &agbp);
 	if (error)
 		return error;
+	if (!agbp)
+		return -ENOMEM;
 
 	cur = xfs_refcountbt_init_cursor(mp, NULL, agbp, agno, NULL);
 
-- 
2.14.1

[PATCH 14/47] xfs: fix quotacheck dquot id overflow infinite loop

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit cfaf2d034360166e569a4929dd83ae9698bed856 upstream.

If a dquot has an id of U32_MAX, the next lookup index increment
overflows the uint32_t back to 0. This starts the lookup sequence
over from the beginning, repeats indefinitely and results in a
livelock.

Update xfs_qm_dquot_walk() to explicitly check for the lookup
overflow and exit the loop.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_qm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index 8068867a8183..1fdd3face2d9 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -111,6 +111,9 @@ xfs_qm_dquot_walk(
 			skipped = 0;
 			break;
 		}
+		/* we're done if id overflows back to zero */
+		if (!next_index)
+			break;
 	}
 
 	if (skipped) {
-- 
2.14.1

[PATCH 15/47] xfs: fix multi-AG deadlock in xfs_bunmapi

[Christoph Hellwig]

commit 5b094d6dac0451ad89b1dc088395c7b399b7e9e8 upstream.

Just like in the allocator we must avoid touching multiple AGs out of
order when freeing blocks, as freeing still locks the AGF and can cause
the same AB-BA deadlocks as in the allocation path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Nikolay Borisov <n.borisov.lkml@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_bmap.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 73571fb4dfed..2ab50caca14c 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -5556,6 +5556,7 @@ __xfs_bunmapi(
 	xfs_fsblock_t		sum;
 	xfs_filblks_t		len = *rlen;	/* length to unmap in file */
 	xfs_fileoff_t		max_len;
+	xfs_agnumber_t		prev_agno = NULLAGNUMBER, agno;
 
 	trace_xfs_bunmap(ip, bno, len, flags, _RET_IP_);
 
@@ -5658,6 +5659,17 @@ __xfs_bunmapi(
 		ASSERT(ep != NULL);
 		del = got;
 		wasdel = isnullstartblock(del.br_startblock);
+
+		/*
+		 * Make sure we don't touch multiple AGF headers out of order
+		 * in a single transaction, as that could cause AB-BA deadlocks.
+		 */
+		if (!wasdel) {
+			agno = XFS_FSB_TO_AGNO(mp, del.br_startblock);
+			if (prev_agno != NULLAGNUMBER && prev_agno > agno)
+				break;
+			prev_agno = agno;
+		}
 		if (got.br_startoff < start) {
 			del.br_startoff = start;
 			del.br_blockcount -= start - got.br_startoff;
-- 
2.14.1

[PATCH 16/47] xfs: Fix per-inode DAX flag inheritance

[Christoph Hellwig]

From: Lukas Czerner <lczerner@redhat.com>

commit 56bdf855e676f1f2ed7033f288f57dfd315725ba upstream.

According to the commit that implemented per-inode DAX flag:
commit 58f88ca2df72 ("xfs: introduce per-inode DAX enablement")
the flag is supposed to act as "inherit flag".

Currently this only works in the situations where parent directory
already has a flag in di_flags set, otherwise inheritance does not
work. This is because setting the XFS_DIFLAG2_DAX flag is done in a
wrong branch designated for di_flags, not di_flags2.

Fix this by moving the code to branch designated for setting di_flags2,
which does test for flags in di_flags2.

Fixes: 58f88ca2df72 ("xfs: introduce per-inode DAX enablement")
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_inode.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 7a0b4eeb99e4..98cd905eadca 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -881,7 +881,6 @@ xfs_ialloc(
 	case S_IFREG:
 	case S_IFDIR:
 		if (pip && (pip->i_d.di_flags & XFS_DIFLAG_ANY)) {
-			uint64_t	di_flags2 = 0;
 			uint		di_flags = 0;
 
 			if (S_ISDIR(mode)) {
@@ -918,20 +917,23 @@ xfs_ialloc(
 				di_flags |= XFS_DIFLAG_NODEFRAG;
 			if (pip->i_d.di_flags & XFS_DIFLAG_FILESTREAM)
 				di_flags |= XFS_DIFLAG_FILESTREAM;
-			if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
-				di_flags2 |= XFS_DIFLAG2_DAX;
 
 			ip->i_d.di_flags |= di_flags;
-			ip->i_d.di_flags2 |= di_flags2;
 		}
 		if (pip &&
 		    (pip->i_d.di_flags2 & XFS_DIFLAG2_ANY) &&
 		    pip->i_d.di_version == 3 &&
 		    ip->i_d.di_version == 3) {
+			uint64_t	di_flags2 = 0;
+
 			if (pip->i_d.di_flags2 & XFS_DIFLAG2_COWEXTSIZE) {
-				ip->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
+				di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
 				ip->i_d.di_cowextsize = pip->i_d.di_cowextsize;
 			}
+			if (pip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
+				di_flags2 |= XFS_DIFLAG2_DAX;
+
+			ip->i_d.di_flags2 |= di_flags2;
 		}
 		/* FALLTHROUGH */
 	case S_IFLNK:
-- 
2.14.1

[PATCH 17/47] xfs: fix inobt inode allocation search optimization

[Christoph Hellwig]

From: Omar Sandoval <osandov@fb.com>

commit c44245b3d5435f533ca8346ece65918f84c057f9 upstream.

When we try to allocate a free inode by searching the inobt, we try to
find the inode nearest the parent inode by searching chunks both left
and right of the chunk containing the parent. As an optimization, we
cache the leftmost and rightmost records that we previously searched; if
we do another allocation with the same parent inode, we'll pick up the
search where it last left off.

There's a bug in the case where we found a free inode to the left of the
parent's chunk: we need to update the cached left and right records, but
because we already reassigned the right record to point to the left, we
end up assigning the left record to both the cached left and right
records.

This isn't a correctness problem strictly, but it can result in the next
allocation rechecking chunks unnecessarily or allocating inodes further
away from the parent than it needs to. Fix it by swapping the record
pointer after we update the cached left and right records.

Fixes: bd169565993b ("xfs: speed up free inode search")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_ialloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index a2818f6e8598..af6acd5f276c 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -1236,13 +1236,13 @@ xfs_dialloc_ag_inobt(
 
 			/* free inodes to the left? */
 			if (useleft && trec.ir_freecount) {
-				rec = trec;
 				xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
 				cur = tcur;
 
 				pag->pagl_leftrec = trec.ir_startino;
 				pag->pagl_rightrec = rec.ir_startino;
 				pag->pagl_pagino = pagino;
+				rec = trec;
 				goto alloc_inode;
 			}
 
-- 
2.14.1

[PATCH 18/47] xfs: clear MS_ACTIVE after finishing log recovery

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit 8204f8ddaafafcae074746fcf2a05a45e6827603 upstream.

Way back when we established inode block-map redo log items, it was
discovered that we needed to prevent the VFS from evicting inodes during
log recovery because any given inode might be have bmap redo items to
replay even if the inode has no link count and is ultimately deleted,
and any eviction of an unlinked inode causes the inode to be truncated
and freed too early.

To make this possible, we set MS_ACTIVE so that inodes would not be torn
down immediately upon release.  Unfortunately, this also results in the
quota inodes not being released at all if a later part of the mount
process should fail, because we never reclaim the inodes.  So, set
MS_ACTIVE right before we do the last part of log recovery and clear it
immediately after we finish the log recovery so that everything
will be torn down properly if we abort the mount.

Fixes: 17c12bcd30 ("xfs: when replaying bmap operations, don't let unlinked inodes get reaped")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
 fs/xfs/xfs_log.c   | 11 +++++++++++
 fs/xfs/xfs_mount.c | 10 ----------
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index b57ab34fbf3c..c235170f3a07 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -749,9 +749,20 @@ xfs_log_mount_finish(
 		return 0;
 	}
 
+	/*
+	 * During the second phase of log recovery, we need iget and
+	 * iput to behave like they do for an active filesystem.
+	 * xfs_fs_drop_inode needs to be able to prevent the deletion
+	 * of inodes before we're done replaying log items on those
+	 * inodes.  Turn it off immediately after recovery finishes
+	 * so that we don't leak the quota inodes if subsequent mount
+	 * activities fail.
+	 */
+	mp->m_super->s_flags |= MS_ACTIVE;
 	error = xlog_recover_finish(mp->m_log);
 	if (!error)
 		xfs_log_work_queue(mp);
+	mp->m_super->s_flags &= ~MS_ACTIVE;
 
 	return error;
 }
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 13796f212f98..ab058c7dc598 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -924,15 +924,6 @@ xfs_mountfs(
 		}
 	}
 
-	/*
-	 * During the second phase of log recovery, we need iget and
-	 * iput to behave like they do for an active filesystem.
-	 * xfs_fs_drop_inode needs to be able to prevent the deletion
-	 * of inodes before we're done replaying log items on those
-	 * inodes.
-	 */
-	mp->m_super->s_flags |= MS_ACTIVE;
-
 	/*
 	 * Finish recovering the file system.  This part needed to be delayed
 	 * until after the root and real-time bitmap inodes were consistently
@@ -1008,7 +999,6 @@ xfs_mountfs(
  out_quota:
 	xfs_qm_unmount_quotas(mp);
  out_rtunmount:
-	mp->m_super->s_flags &= ~MS_ACTIVE;
 	xfs_rtunmount_inodes(mp);
  out_rele_rip:
 	IRELE(rip);
-- 
2.14.1

[PATCH 19/47] xfs: don't leak quotacheck dquots when cow recovery

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit 77aff8c76425c8f49b50d0b9009915066739e7d2 upstream.

If we fail a mount on account of cow recovery errors, it's possible that
a previous quotacheck left some dquots in memory.  The bailout clause of
xfs_mountfs forgets to purge these, and so we leak them.  Fix that.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
 fs/xfs/xfs_mount.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index ab058c7dc598..d4ce8d277992 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -1004,6 +1004,8 @@ xfs_mountfs(
 	IRELE(rip);
 	cancel_delayed_work_sync(&mp->m_reclaim_work);
 	xfs_reclaim_inodes(mp, SYNC_WAIT);
+	/* Clean out dquots that might be in memory after quotacheck. */
+	xfs_qm_unmount(mp);
  out_log_dealloc:
 	mp->m_flags |= XFS_MOUNT_UNMOUNTING;
 	xfs_log_mount_cancel(mp);
-- 
2.14.1

[PATCH 20/47] iomap: fix integer truncation issues in the zeroing and dirtying helpers

[Christoph Hellwig]

commit e28ae8e428fefe2facd72cea9f29906ecb9c861d upstream.

Fix the min_t calls in the zeroing and dirtying helpers to perform the
comparisms on 64-bit types, which prevents them from incorrectly
being truncated, and larger zeroing operations being stuck in a never
ending loop.

Special thanks to Markus Stockhausen for spotting the bug.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/iomap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/iomap.c b/fs/iomap.c
index 798c291cbc75..a49db8806a3a 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -281,7 +281,7 @@ iomap_dirty_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
 		unsigned long bytes;	/* Bytes to write to page */
 
 		offset = (pos & (PAGE_SIZE - 1));
-		bytes = min_t(unsigned long, PAGE_SIZE - offset, length);
+		bytes = min_t(loff_t, PAGE_SIZE - offset, length);
 
 		rpage = __iomap_read_page(inode, pos);
 		if (IS_ERR(rpage))
@@ -376,7 +376,7 @@ iomap_zero_range_actor(struct inode *inode, loff_t pos, loff_t count,
 		unsigned offset, bytes;
 
 		offset = pos & (PAGE_SIZE - 1); /* Within page */
-		bytes = min_t(unsigned, PAGE_SIZE - offset, count);
+		bytes = min_t(loff_t, PAGE_SIZE - offset, count);
 
 		if (IS_DAX(inode))
 			status = iomap_dax_zero(pos, offset, bytes, iomap);
-- 
2.14.1

[PATCH 21/47] xfs: write unmount record for ro mounts

[Christoph Hellwig]

From: Eric Sandeen <sandeen@sandeen.net>

commit 757a69ef6cf2bf839bd4088e5609ddddd663b0c4 upstream.

There are dueling comments in the xfs code about intent
for log writes when unmounting a readonly filesystem.

In xfs_mountfs, we see the intent:

/*
 * Now the log is fully replayed, we can transition to full read-only
 * mode for read-only mounts. This will sync all the metadata and clean
 * the log so that the recovery we just performed does not have to be
 * replayed again on the next mount.
 */

and it calls xfs_quiesce_attr(), but by the time we get to
xfs_log_unmount_write(), it returns early for a RDONLY mount:

 * Don't write out unmount record on read-only mounts.

Because of this, sequential ro mounts of a filesystem with
a dirty log will replay the log each time, which seems odd.

Fix this by writing an unmount record even for RO mounts, as long
as norecovery wasn't specified (don't write a clean log record
if a dirty log may still be there!) and the log device is
writable.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index c235170f3a07..4f59cbc0b185 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -812,11 +812,14 @@ xfs_log_unmount_write(xfs_mount_t *mp)
 	int		 error;
 
 	/*
-	 * Don't write out unmount record on read-only mounts.
+	 * Don't write out unmount record on norecovery mounts or ro devices.
 	 * Or, if we are doing a forced umount (typically because of IO errors).
 	 */
-	if (mp->m_flags & XFS_MOUNT_RDONLY)
+	if (mp->m_flags & XFS_MOUNT_NORECOVERY ||
+	    xfs_readonly_buftarg(log->l_mp->m_logdev_targp)) {
+		ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
 		return 0;
+	}
 
 	error = _xfs_log_force(mp, XFS_LOG_SYNC, NULL);
 	ASSERT(error || !(XLOG_FORCED_SHUTDOWN(log)));
-- 
2.14.1

[PATCH 22/47] xfs: toggle readonly state around xfs_log_mount_finish

[Christoph Hellwig]

From: Eric Sandeen <sandeen@sandeen.net>

commit 6f4a1eefdd0ad4561543270a7fceadabcca075dd upstream.

When we do log recovery on a readonly mount, unlinked inode
processing does not happen due to the readonly checks in
xfs_inactive(), which are trying to prevent any I/O on a
readonly mount.

This is misguided - we do I/O on readonly mounts all the time,
for consistency; for example, log recovery.  So do the same
RDONLY flag twiddling around xfs_log_mount_finish() as we
do around xfs_log_mount(), for the same reason.

This all cries out for a big rework but for now this is a
simple fix to an obvious problem.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 4f59cbc0b185..ebe20f1591f1 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -743,10 +743,14 @@ xfs_log_mount_finish(
 	struct xfs_mount	*mp)
 {
 	int	error = 0;
+	bool	readonly = (mp->m_flags & XFS_MOUNT_RDONLY);
 
 	if (mp->m_flags & XFS_MOUNT_NORECOVERY) {
 		ASSERT(mp->m_flags & XFS_MOUNT_RDONLY);
 		return 0;
+	} else if (readonly) {
+		/* Allow unlinked processing to proceed */
+		mp->m_flags &= ~XFS_MOUNT_RDONLY;
 	}
 
 	/*
@@ -764,6 +768,9 @@ xfs_log_mount_finish(
 		xfs_log_work_queue(mp);
 	mp->m_super->s_flags &= ~MS_ACTIVE;
 
+	if (readonly)
+		mp->m_flags |= XFS_MOUNT_RDONLY;
+
 	return error;
 }
 
-- 
2.14.1

[PATCH 23/47] xfs: remove xfs_trans_ail_delete_bulk

[Christoph Hellwig]

commit 27af1bbf524459962d1477a38ac6e0b7f79aaecc upstream.

xfs_iflush_done uses an on-stack variable length array to pass the log
items to be deleted to xfs_trans_ail_delete_bulk.  On-stack VLAs are a
nasty gcc extension that can lead to unbounded stack allocations, but
fortunately we can easily avoid them by simply open coding
xfs_trans_ail_delete_bulk in xfs_iflush_done, which is the only caller
of it except for the single-item xfs_trans_ail_delete.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_inode_item.c | 29 +++++++++++---------
 fs/xfs/xfs_trans_ail.c  | 71 ++++++++++++++++++++++++-------------------------
 fs/xfs/xfs_trans_priv.h | 15 +++--------
 3 files changed, 55 insertions(+), 60 deletions(-)

diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
index d90e7811ccdd..08cb7d1a4a3a 100644
--- a/fs/xfs/xfs_inode_item.c
+++ b/fs/xfs/xfs_inode_item.c
@@ -731,22 +731,27 @@ xfs_iflush_done(
 	 * holding the lock before removing the inode from the AIL.
 	 */
 	if (need_ail) {
-		struct xfs_log_item *log_items[need_ail];
-		int i = 0;
+		bool			mlip_changed = false;
+
+		/* this is an opencoded batch version of xfs_trans_ail_delete */
 		spin_lock(&ailp->xa_lock);
 		for (blip = lip; blip; blip = blip->li_bio_list) {
-			iip = INODE_ITEM(blip);
-			if (iip->ili_logged &&
-			    blip->li_lsn == iip->ili_flush_lsn) {
-				log_items[i++] = blip;
-			}
-			ASSERT(i <= need_ail);
+			if (INODE_ITEM(blip)->ili_logged &&
+			    blip->li_lsn == INODE_ITEM(blip)->ili_flush_lsn)
+				mlip_changed |= xfs_ail_delete_one(ailp, blip);
 		}
-		/* xfs_trans_ail_delete_bulk() drops the AIL lock. */
-		xfs_trans_ail_delete_bulk(ailp, log_items, i,
-					  SHUTDOWN_CORRUPT_INCORE);
-	}
 
+		if (mlip_changed) {
+			if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount))
+				xlog_assign_tail_lsn_locked(ailp->xa_mount);
+			if (list_empty(&ailp->xa_ail))
+				wake_up_all(&ailp->xa_empty);
+		}
+		spin_unlock(&ailp->xa_lock);
+
+		if (mlip_changed)
+			xfs_log_space_wake(ailp->xa_mount);
+	}
 
 	/*
 	 * clean up and unlock the flush lock now we are done. We can clear the
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index d6c9c3e9e02b..9056c0f34a3c 100644
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -684,8 +684,23 @@ xfs_trans_ail_update_bulk(
 	}
 }
 
-/*
- * xfs_trans_ail_delete_bulk - remove multiple log items from the AIL
+bool
+xfs_ail_delete_one(
+	struct xfs_ail		*ailp,
+	struct xfs_log_item 	*lip)
+{
+	struct xfs_log_item	*mlip = xfs_ail_min(ailp);
+
+	trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
+	xfs_ail_delete(ailp, lip);
+	lip->li_flags &= ~XFS_LI_IN_AIL;
+	lip->li_lsn = 0;
+
+	return mlip == lip;
+}
+
+/**
+ * Remove a log items from the AIL
  *
  * @xfs_trans_ail_delete_bulk takes an array of log items that all need to
  * removed from the AIL. The caller is already holding the AIL lock, and done
@@ -706,52 +721,36 @@ xfs_trans_ail_update_bulk(
  * before returning.
  */
 void
-xfs_trans_ail_delete_bulk(
+xfs_trans_ail_delete(
 	struct xfs_ail		*ailp,
-	struct xfs_log_item	**log_items,
-	int			nr_items,
+	struct xfs_log_item	*lip,
 	int			shutdown_type) __releases(ailp->xa_lock)
 {
-	xfs_log_item_t		*mlip;
-	int			mlip_changed = 0;
-	int			i;
+	struct xfs_mount	*mp = ailp->xa_mount;
+	bool			mlip_changed;
 
-	mlip = xfs_ail_min(ailp);
-
-	for (i = 0; i < nr_items; i++) {
-		struct xfs_log_item *lip = log_items[i];
-		if (!(lip->li_flags & XFS_LI_IN_AIL)) {
-			struct xfs_mount	*mp = ailp->xa_mount;
-
-			spin_unlock(&ailp->xa_lock);
-			if (!XFS_FORCED_SHUTDOWN(mp)) {
-				xfs_alert_tag(mp, XFS_PTAG_AILDELETE,
-		"%s: attempting to delete a log item that is not in the AIL",
-						__func__);
-				xfs_force_shutdown(mp, shutdown_type);
-			}
-			return;
+	if (!(lip->li_flags & XFS_LI_IN_AIL)) {
+		spin_unlock(&ailp->xa_lock);
+		if (!XFS_FORCED_SHUTDOWN(mp)) {
+			xfs_alert_tag(mp, XFS_PTAG_AILDELETE,
+	"%s: attempting to delete a log item that is not in the AIL",
+					__func__);
+			xfs_force_shutdown(mp, shutdown_type);
 		}
-
-		trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
-		xfs_ail_delete(ailp, lip);
-		lip->li_flags &= ~XFS_LI_IN_AIL;
-		lip->li_lsn = 0;
-		if (mlip == lip)
-			mlip_changed = 1;
+		return;
 	}
 
+	mlip_changed = xfs_ail_delete_one(ailp, lip);
 	if (mlip_changed) {
-		if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount))
-			xlog_assign_tail_lsn_locked(ailp->xa_mount);
+		if (!XFS_FORCED_SHUTDOWN(mp))
+			xlog_assign_tail_lsn_locked(mp);
 		if (list_empty(&ailp->xa_ail))
 			wake_up_all(&ailp->xa_empty);
-		spin_unlock(&ailp->xa_lock);
+	}
 
+	spin_unlock(&ailp->xa_lock);
+	if (mlip_changed)
 		xfs_log_space_wake(ailp->xa_mount);
-	} else {
-		spin_unlock(&ailp->xa_lock);
-	}
 }
 
 int
diff --git a/fs/xfs/xfs_trans_priv.h b/fs/xfs/xfs_trans_priv.h
index 49931b72da8a..d91706c56c63 100644
--- a/fs/xfs/xfs_trans_priv.h
+++ b/fs/xfs/xfs_trans_priv.h
@@ -106,18 +106,9 @@ xfs_trans_ail_update(
 	xfs_trans_ail_update_bulk(ailp, NULL, &lip, 1, lsn);
 }
 
-void	xfs_trans_ail_delete_bulk(struct xfs_ail *ailp,
-				struct xfs_log_item **log_items, int nr_items,
-				int shutdown_type)
-				__releases(ailp->xa_lock);
-static inline void
-xfs_trans_ail_delete(
-	struct xfs_ail	*ailp,
-	xfs_log_item_t	*lip,
-	int		shutdown_type) __releases(ailp->xa_lock)
-{
-	xfs_trans_ail_delete_bulk(ailp, &lip, 1, shutdown_type);
-}
+bool xfs_ail_delete_one(struct xfs_ail *ailp, struct xfs_log_item *lip);
+void xfs_trans_ail_delete(struct xfs_ail *ailp, struct xfs_log_item *lip,
+		int shutdown_type) __releases(ailp->xa_lock);
 
 static inline void
 xfs_trans_ail_remove(
-- 
2.14.1

[PATCH 24/47] xfs: Add infrastructure needed for error propagation during buffer IO failure

[Christoph Hellwig]

From: Carlos Maiolino <cmaiolino@redhat.com>

commit 0b80ae6ed13169bd3a244e71169f2cc020b0c57a upstream.

With the current code, XFS never re-submit a failed buffer for IO,
because the failed item in the buffer is kept in the flush locked state
forever.

To be able to resubmit an log item for IO, we need a way to mark an item
as failed, if, for any reason the buffer which the item belonged to
failed during writeback.

Add a new log item callback to be used after an IO completion failure
and make the needed clean ups.

Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf_item.c | 32 +++++++++++++++++++++++++++++++-
 fs/xfs/xfs_trans.h    |  7 +++++--
 2 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index f6a8422e9562..7573a1f0bc9a 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -29,6 +29,7 @@
 #include "xfs_error.h"
 #include "xfs_trace.h"
 #include "xfs_log.h"
+#include "xfs_inode.h"
 
 
 kmem_zone_t	*xfs_buf_item_zone;
@@ -1054,6 +1055,31 @@ xfs_buf_do_callbacks(
 	}
 }
 
+/*
+ * Invoke the error state callback for each log item affected by the failed I/O.
+ *
+ * If a metadata buffer write fails with a non-permanent error, the buffer is
+ * eventually resubmitted and so the completion callbacks are not run. The error
+ * state may need to be propagated to the log items attached to the buffer,
+ * however, so the next AIL push of the item knows hot to handle it correctly.
+ */
+STATIC void
+xfs_buf_do_callbacks_fail(
+	struct xfs_buf		*bp)
+{
+	struct xfs_log_item	*next;
+	struct xfs_log_item	*lip = bp->b_fspriv;
+	struct xfs_ail		*ailp = lip->li_ailp;
+
+	spin_lock(&ailp->xa_lock);
+	for (; lip; lip = next) {
+		next = lip->li_bio_list;
+		if (lip->li_ops->iop_error)
+			lip->li_ops->iop_error(lip, bp);
+	}
+	spin_unlock(&ailp->xa_lock);
+}
+
 static bool
 xfs_buf_iodone_callback_error(
 	struct xfs_buf		*bp)
@@ -1123,7 +1149,11 @@ xfs_buf_iodone_callback_error(
 	if ((mp->m_flags & XFS_MOUNT_UNMOUNTING) && mp->m_fail_unmount)
 		goto permanent_error;
 
-	/* still a transient error, higher layers will retry */
+	/*
+	 * Still a transient error, run IO completion failure callbacks and let
+	 * the higher layers retry the buffer.
+	 */
+	xfs_buf_do_callbacks_fail(bp);
 	xfs_buf_ioerror(bp, 0);
 	xfs_buf_relse(bp);
 	return true;
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index c0e72ab57741..22fddad9fe11 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -65,11 +65,13 @@ typedef struct xfs_log_item {
 } xfs_log_item_t;
 
 #define	XFS_LI_IN_AIL	0x1
-#define XFS_LI_ABORTED	0x2
+#define	XFS_LI_ABORTED	0x2
+#define	XFS_LI_FAILED	0x4
 
 #define XFS_LI_FLAGS \
 	{ XFS_LI_IN_AIL,	"IN_AIL" }, \
-	{ XFS_LI_ABORTED,	"ABORTED" }
+	{ XFS_LI_ABORTED,	"ABORTED" }, \
+	{ XFS_LI_FAILED,	"FAILED" }
 
 struct xfs_item_ops {
 	void (*iop_size)(xfs_log_item_t *, int *, int *);
@@ -80,6 +82,7 @@ struct xfs_item_ops {
 	void (*iop_unlock)(xfs_log_item_t *);
 	xfs_lsn_t (*iop_committed)(xfs_log_item_t *, xfs_lsn_t);
 	void (*iop_committing)(xfs_log_item_t *, xfs_lsn_t);
+	void (*iop_error)(xfs_log_item_t *, xfs_buf_t *);
 };
 
 void	xfs_log_item_init(struct xfs_mount *mp, struct xfs_log_item *item,
-- 
2.14.1

[PATCH 25/47] xfs: Properly retry failed inode items in case of error during buffer writeback

[Christoph Hellwig]

From: Carlos Maiolino <cmaiolino@redhat.com>

commit d3a304b6292168b83b45d624784f973fdc1ca674 upstream.

When a buffer has been failed during writeback, the inode items into it
are kept flush locked, and are never resubmitted due the flush lock, so,
if any buffer fails to be written, the items in AIL are never written to
disk and never unlocked.

This causes unmount operation to hang due these items flush locked in AIL,
but this also causes the items in AIL to never be written back, even when
the IO device comes back to normal.

I've been testing this patch with a DM-thin device, creating a
filesystem larger than the real device.

When writing enough data to fill the DM-thin device, XFS receives ENOSPC
errors from the device, and keep spinning on xfsaild (when 'retry
forever' configuration is set).

At this point, the filesystem can not be unmounted because of the flush locked
items in AIL, but worse, the items in AIL are never retried at all
(once xfs_inode_item_push() will skip the items that are flush locked),
even if the underlying DM-thin device is expanded to the proper size.

This patch fixes both cases, retrying any item that has been failed
previously, using the infra-structure provided by the previous patch.

Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf_item.c   | 28 ++++++++++++++++++++++++++++
 fs/xfs/xfs_buf_item.h   |  3 +++
 fs/xfs/xfs_inode_item.c | 47 +++++++++++++++++++++++++++++++++++++++++++----
 fs/xfs/xfs_trans.h      |  1 +
 fs/xfs/xfs_trans_ail.c  |  3 ++-
 fs/xfs/xfs_trans_priv.h | 31 +++++++++++++++++++++++++++++++
 6 files changed, 108 insertions(+), 5 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 7573a1f0bc9a..573fc72c3f23 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -1234,3 +1234,31 @@ xfs_buf_iodone(
 	xfs_trans_ail_delete(ailp, lip, SHUTDOWN_CORRUPT_INCORE);
 	xfs_buf_item_free(BUF_ITEM(lip));
 }
+
+/*
+ * Requeue a failed buffer for writeback
+ *
+ * Return true if the buffer has been re-queued properly, false otherwise
+ */
+bool
+xfs_buf_resubmit_failed_buffers(
+	struct xfs_buf		*bp,
+	struct xfs_log_item	*lip,
+	struct list_head	*buffer_list)
+{
+	struct xfs_log_item	*next;
+
+	/*
+	 * Clear XFS_LI_FAILED flag from all items before resubmit
+	 *
+	 * XFS_LI_FAILED set/clear is protected by xa_lock, caller  this
+	 * function already have it acquired
+	 */
+	for (; lip; lip = next) {
+		next = lip->li_bio_list;
+		xfs_clear_li_failed(lip);
+	}
+
+	/* Add this buffer back to the delayed write list */
+	return xfs_buf_delwri_queue(bp, buffer_list);
+}
diff --git a/fs/xfs/xfs_buf_item.h b/fs/xfs/xfs_buf_item.h
index f7eba99d19dd..530686e1afb9 100644
--- a/fs/xfs/xfs_buf_item.h
+++ b/fs/xfs/xfs_buf_item.h
@@ -70,6 +70,9 @@ void	xfs_buf_attach_iodone(struct xfs_buf *,
 			      xfs_log_item_t *);
 void	xfs_buf_iodone_callbacks(struct xfs_buf *);
 void	xfs_buf_iodone(struct xfs_buf *, struct xfs_log_item *);
+bool	xfs_buf_resubmit_failed_buffers(struct xfs_buf *,
+					struct xfs_log_item *,
+					struct list_head *);
 
 extern kmem_zone_t	*xfs_buf_item_zone;
 
diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
index 08cb7d1a4a3a..94915747042c 100644
--- a/fs/xfs/xfs_inode_item.c
+++ b/fs/xfs/xfs_inode_item.c
@@ -27,6 +27,7 @@
 #include "xfs_error.h"
 #include "xfs_trace.h"
 #include "xfs_trans_priv.h"
+#include "xfs_buf_item.h"
 #include "xfs_log.h"
 
 
@@ -475,6 +476,23 @@ xfs_inode_item_unpin(
 		wake_up_bit(&ip->i_flags, __XFS_IPINNED_BIT);
 }
 
+/*
+ * Callback used to mark a buffer with XFS_LI_FAILED when items in the buffer
+ * have been failed during writeback
+ *
+ * This informs the AIL that the inode is already flush locked on the next push,
+ * and acquires a hold on the buffer to ensure that it isn't reclaimed before
+ * dirty data makes it to disk.
+ */
+STATIC void
+xfs_inode_item_error(
+	struct xfs_log_item	*lip,
+	struct xfs_buf		*bp)
+{
+	ASSERT(xfs_isiflocked(INODE_ITEM(lip)->ili_inode));
+	xfs_set_li_failed(lip, bp);
+}
+
 STATIC uint
 xfs_inode_item_push(
 	struct xfs_log_item	*lip,
@@ -484,13 +502,28 @@ xfs_inode_item_push(
 {
 	struct xfs_inode_log_item *iip = INODE_ITEM(lip);
 	struct xfs_inode	*ip = iip->ili_inode;
-	struct xfs_buf		*bp = NULL;
+	struct xfs_buf		*bp = lip->li_buf;
 	uint			rval = XFS_ITEM_SUCCESS;
 	int			error;
 
 	if (xfs_ipincount(ip) > 0)
 		return XFS_ITEM_PINNED;
 
+	/*
+	 * The buffer containing this item failed to be written back
+	 * previously. Resubmit the buffer for IO.
+	 */
+	if (lip->li_flags & XFS_LI_FAILED) {
+		if (!xfs_buf_trylock(bp))
+			return XFS_ITEM_LOCKED;
+
+		if (!xfs_buf_resubmit_failed_buffers(bp, lip, buffer_list))
+			rval = XFS_ITEM_FLUSHING;
+
+		xfs_buf_unlock(bp);
+		return rval;
+	}
+
 	if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED))
 		return XFS_ITEM_LOCKED;
 
@@ -622,7 +655,8 @@ static const struct xfs_item_ops xfs_inode_item_ops = {
 	.iop_unlock	= xfs_inode_item_unlock,
 	.iop_committed	= xfs_inode_item_committed,
 	.iop_push	= xfs_inode_item_push,
-	.iop_committing = xfs_inode_item_committing
+	.iop_committing = xfs_inode_item_committing,
+	.iop_error	= xfs_inode_item_error
 };
 
 
@@ -710,7 +744,8 @@ xfs_iflush_done(
 		 * the AIL lock.
 		 */
 		iip = INODE_ITEM(blip);
-		if (iip->ili_logged && blip->li_lsn == iip->ili_flush_lsn)
+		if ((iip->ili_logged && blip->li_lsn == iip->ili_flush_lsn) ||
+		    lip->li_flags & XFS_LI_FAILED)
 			need_ail++;
 
 		blip = next;
@@ -718,7 +753,8 @@ xfs_iflush_done(
 
 	/* make sure we capture the state of the initial inode. */
 	iip = INODE_ITEM(lip);
-	if (iip->ili_logged && lip->li_lsn == iip->ili_flush_lsn)
+	if ((iip->ili_logged && lip->li_lsn == iip->ili_flush_lsn) ||
+	    lip->li_flags & XFS_LI_FAILED)
 		need_ail++;
 
 	/*
@@ -739,6 +775,9 @@ xfs_iflush_done(
 			if (INODE_ITEM(blip)->ili_logged &&
 			    blip->li_lsn == INODE_ITEM(blip)->ili_flush_lsn)
 				mlip_changed |= xfs_ail_delete_one(ailp, blip);
+			else {
+				xfs_clear_li_failed(blip);
+			}
 		}
 
 		if (mlip_changed) {
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 22fddad9fe11..0318e92aed66 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -50,6 +50,7 @@ typedef struct xfs_log_item {
 	struct xfs_ail			*li_ailp;	/* ptr to AIL */
 	uint				li_type;	/* item type */
 	uint				li_flags;	/* misc flags */
+	struct xfs_buf			*li_buf;	/* real buffer pointer */
 	struct xfs_log_item		*li_bio_list;	/* buffer item list */
 	void				(*li_cb)(struct xfs_buf *,
 						 struct xfs_log_item *);
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index 9056c0f34a3c..70f5ab017323 100644
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -687,12 +687,13 @@ xfs_trans_ail_update_bulk(
 bool
 xfs_ail_delete_one(
 	struct xfs_ail		*ailp,
-	struct xfs_log_item 	*lip)
+	struct xfs_log_item	*lip)
 {
 	struct xfs_log_item	*mlip = xfs_ail_min(ailp);
 
 	trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
 	xfs_ail_delete(ailp, lip);
+	xfs_clear_li_failed(lip);
 	lip->li_flags &= ~XFS_LI_IN_AIL;
 	lip->li_lsn = 0;
 
diff --git a/fs/xfs/xfs_trans_priv.h b/fs/xfs/xfs_trans_priv.h
index d91706c56c63..b317a3644c00 100644
--- a/fs/xfs/xfs_trans_priv.h
+++ b/fs/xfs/xfs_trans_priv.h
@@ -164,4 +164,35 @@ xfs_trans_ail_copy_lsn(
 	*dst = *src;
 }
 #endif
+
+static inline void
+xfs_clear_li_failed(
+	struct xfs_log_item	*lip)
+{
+	struct xfs_buf	*bp = lip->li_buf;
+
+	ASSERT(lip->li_flags & XFS_LI_IN_AIL);
+	lockdep_assert_held(&lip->li_ailp->xa_lock);
+
+	if (lip->li_flags & XFS_LI_FAILED) {
+		lip->li_flags &= ~XFS_LI_FAILED;
+		lip->li_buf = NULL;
+		xfs_buf_rele(bp);
+	}
+}
+
+static inline void
+xfs_set_li_failed(
+	struct xfs_log_item	*lip,
+	struct xfs_buf		*bp)
+{
+	lockdep_assert_held(&lip->li_ailp->xa_lock);
+
+	if (!(lip->li_flags & XFS_LI_FAILED)) {
+		xfs_buf_hold(bp);
+		lip->li_flags |= XFS_LI_FAILED;
+		lip->li_buf = bp;
+	}
+}
+
 #endif	/* __XFS_TRANS_PRIV_H__ */
-- 
2.14.1

[PATCH 26/47] xfs: fix recovery failure when log record header wraps log end

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 284f1c2c9bebf871861184b0e2c40fa921dd380b upstream.

The high-level log recovery algorithm consists of two loops that
walk the physical log and process log records from the tail to the
head. The first loop handles the case where the tail is beyond the
head and processes records up to the end of the physical log. The
subsequent loop processes records from the beginning of the physical
log to the head.

Because log records can wrap around the end of the physical log, the
first loop mentioned above must handle this case appropriately.
Records are processed from in-core buffers, which means that this
algorithm must split the reads of such records into two partial
I/Os: 1.) from the beginning of the record to the end of the log and
2.) from the beginning of the log to the end of the record. This is
further complicated by the fact that the log record header and log
record data are read into independent buffers.

The current handling of each buffer correctly splits the reads when
either the header or data starts before the end of the log and wraps
around the end. The data read does not correctly handle the case
where the prior header read wrapped or ends on the physical log end
boundary. blk_no is incremented to or beyond the log end after the
header read to point to the record data, but the split data read
logic triggers, attempts to read from an invalid log block and
ultimately causes log recovery to fail. This can be reproduced
fairly reliably via xfstests tests generic/047 and generic/388 with
large iclog sizes (256k) and small (10M) logs.

If the record header read has pushed beyond the end of the physical
log, the subsequent data read is actually contiguous. Update the
data read logic to detect the case where blk_no has wrapped, mod it
against the log size to read from the correct address and issue one
contiguous read for the log data buffer. The log record is processed
as normal from the buffer(s), the loop exits after the current
iteration and the subsequent loop picks up with the first new record
after the start of the log.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log_recover.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index e06aa2827ecb..9cef8916314a 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -5216,7 +5216,7 @@ xlog_do_recovery_pass(
 	xfs_daddr_t		*first_bad)	/* out: first bad log rec */
 {
 	xlog_rec_header_t	*rhead;
-	xfs_daddr_t		blk_no;
+	xfs_daddr_t		blk_no, rblk_no;
 	xfs_daddr_t		rhead_blk;
 	char			*offset;
 	xfs_buf_t		*hbp, *dbp;
@@ -5369,9 +5369,19 @@ xlog_do_recovery_pass(
 			bblks = (int)BTOBB(be32_to_cpu(rhead->h_len));
 			blk_no += hblks;
 
-			/* Read in data for log record */
-			if (blk_no + bblks <= log->l_logBBsize) {
-				error = xlog_bread(log, blk_no, bblks, dbp,
+			/*
+			 * Read the log record data in multiple reads if it
+			 * wraps around the end of the log. Note that if the
+			 * header already wrapped, blk_no could point past the
+			 * end of the log. The record data is contiguous in
+			 * that case.
+			 */
+			if (blk_no + bblks <= log->l_logBBsize ||
+			    blk_no >= log->l_logBBsize) {
+				/* mod blk_no in case the header wrapped and
+				 * pushed it beyond the end of the log */
+				rblk_no = do_mod(blk_no, log->l_logBBsize);
+				error = xlog_bread(log, rblk_no, bblks, dbp,
 						   &offset);
 				if (error)
 					goto bread_err2;
-- 
2.14.1

[PATCH 27/47] xfs: always verify the log tail during recovery

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 5297ac1f6d7cbf45464a49b9558831f271dfc559 upstream.

Log tail verification currently only occurs when torn writes are
detected at the head of the log. This was introduced because a
change in the head block due to torn writes can lead to a change in
the tail block (each log record header references the current tail)
and the tail block should be verified before log recovery proceeds.

Tail corruption is possible outside of torn write scenarios,
however. For example, partial log writes can be detected and cleared
during the initial head/tail block discovery process. If the partial
write coincides with a tail overwrite, the log tail is corrupted and
recovery fails.

To facilitate correct handling of log tail overwites, update log
recovery to always perform tail verification. This is necessary to
detect potential tail overwrite conditions when torn writes may not
have occurred. This changes normal (i.e., no torn writes) recovery
behavior slightly to detect and return CRC related errors near the
tail before actual recovery starts.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log_recover.c | 26 +++-----------------------
 1 file changed, 3 insertions(+), 23 deletions(-)

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 9cef8916314a..1457fa0f8637 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -1183,31 +1183,11 @@ xlog_verify_head(
 			ASSERT(0);
 			return 0;
 		}
-
-		/*
-		 * Now verify the tail based on the updated head. This is
-		 * required because the torn writes trimmed from the head could
-		 * have been written over the tail of a previous record. Return
-		 * any errors since recovery cannot proceed if the tail is
-		 * corrupt.
-		 *
-		 * XXX: This leaves a gap in truly robust protection from torn
-		 * writes in the log. If the head is behind the tail, the tail
-		 * pushes forward to create some space and then a crash occurs
-		 * causing the writes into the previous record's tail region to
-		 * tear, log recovery isn't able to recover.
-		 *
-		 * How likely is this to occur? If possible, can we do something
-		 * more intelligent here? Is it safe to push the tail forward if
-		 * we can determine that the tail is within the range of the
-		 * torn write (e.g., the kernel can only overwrite the tail if
-		 * it has actually been pushed forward)? Alternatively, could we
-		 * somehow prevent this condition at runtime?
-		 */
-		error = xlog_verify_tail(log, *head_blk, *tail_blk);
 	}
+	if (error)
+		return error;
 
-	return error;
+	return xlog_verify_tail(log, *head_blk, *tail_blk);
 }
 
 /*
-- 
2.14.1

[PATCH 28/47] xfs: fix log recovery corruption error due to tail overwrite

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 4a4f66eac4681378996a1837ad1ffec3a2e2981f upstream.

If we consider the case where the tail (T) of the log is pinned long
enough for the head (H) to push and block behind the tail, we can
end up blocked in the following state without enough free space (f)
in the log to satisfy a transaction reservation:

	0	phys. log	N
	[-------HffT---H'--T'---]

The last good record in the log (before H) refers to T. The tail
eventually pushes forward (T') leaving more free space in the log
for writes to H. At this point, suppose space frees up in the log
for the maximum of 8 in-core log buffers to start flushing out to
the log. If this pushes the head from H to H', these next writes
overwrite the previous tail T. This is safe because the items logged
from T to T' have been written back and removed from the AIL.

If the next log writes (H -> H') happen to fail and result in
partial records in the log, the filesystem shuts down having
overwritten T with invalid data. Log recovery correctly locates H on
the subsequent mount, but H still refers to the now corrupted tail
T. This results in log corruption errors and recovery failure.

Since the tail overwrite results from otherwise correct runtime
behavior, it is up to log recovery to try and deal with this
situation. Update log recovery tail verification to run a CRC pass
from the first record past the tail to the head. This facilitates
error detection at T and moves the recovery tail to the first good
record past H' (similar to truncating the head on torn write
detection). If corruption is detected beyond the range possibly
affected by the max number of iclogs, the log is legitimately
corrupted and log recovery failure is expected.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log_recover.c | 108 +++++++++++++++++++++++++++++++++--------------
 1 file changed, 77 insertions(+), 31 deletions(-)

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 1457fa0f8637..fdad8c9ecbb3 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -1029,61 +1029,106 @@ xlog_seek_logrec_hdr(
 }
 
 /*
- * Check the log tail for torn writes. This is required when torn writes are
- * detected at the head and the head had to be walked back to a previous record.
- * The tail of the previous record must now be verified to ensure the torn
- * writes didn't corrupt the previous tail.
+ * Calculate distance from head to tail (i.e., unused space in the log).
+ */
+static inline int
+xlog_tail_distance(
+	struct xlog	*log,
+	xfs_daddr_t	head_blk,
+	xfs_daddr_t	tail_blk)
+{
+	if (head_blk < tail_blk)
+		return tail_blk - head_blk;
+
+	return tail_blk + (log->l_logBBsize - head_blk);
+}
+
+/*
+ * Verify the log tail. This is particularly important when torn or incomplete
+ * writes have been detected near the front of the log and the head has been
+ * walked back accordingly.
+ *
+ * We also have to handle the case where the tail was pinned and the head
+ * blocked behind the tail right before a crash. If the tail had been pushed
+ * immediately prior to the crash and the subsequent checkpoint was only
+ * partially written, it's possible it overwrote the last referenced tail in the
+ * log with garbage. This is not a coherency problem because the tail must have
+ * been pushed before it can be overwritten, but appears as log corruption to
+ * recovery because we have no way to know the tail was updated if the
+ * subsequent checkpoint didn't write successfully.
  *
- * Return an error if CRC verification fails as recovery cannot proceed.
+ * Therefore, CRC check the log from tail to head. If a failure occurs and the
+ * offending record is within max iclog bufs from the head, walk the tail
+ * forward and retry until a valid tail is found or corruption is detected out
+ * of the range of a possible overwrite.
  */
 STATIC int
 xlog_verify_tail(
 	struct xlog		*log,
 	xfs_daddr_t		head_blk,
-	xfs_daddr_t		tail_blk)
+	xfs_daddr_t		*tail_blk,
+	int			hsize)
 {
 	struct xlog_rec_header	*thead;
 	struct xfs_buf		*bp;
 	xfs_daddr_t		first_bad;
-	int			count;
 	int			error = 0;
 	bool			wrapped;
-	xfs_daddr_t		tmp_head;
+	xfs_daddr_t		tmp_tail;
+	xfs_daddr_t		orig_tail = *tail_blk;
 
 	bp = xlog_get_bp(log, 1);
 	if (!bp)
 		return -ENOMEM;
 
 	/*
-	 * Seek XLOG_MAX_ICLOGS + 1 records past the current tail record to get
-	 * a temporary head block that points after the last possible
-	 * concurrently written record of the tail.
+	 * Make sure the tail points to a record (returns positive count on
+	 * success).
 	 */
-	count = xlog_seek_logrec_hdr(log, head_blk, tail_blk,
-				     XLOG_MAX_ICLOGS + 1, bp, &tmp_head, &thead,
-				     &wrapped);
-	if (count < 0) {
-		error = count;
+	error = xlog_seek_logrec_hdr(log, head_blk, *tail_blk, 1, bp,
+			&tmp_tail, &thead, &wrapped);
+	if (error < 0)
 		goto out;
-	}
+	if (*tail_blk != tmp_tail)
+		*tail_blk = tmp_tail;
 
 	/*
-	 * If the call above didn't find XLOG_MAX_ICLOGS + 1 records, we ran
-	 * into the actual log head. tmp_head points to the start of the record
-	 * so update it to the actual head block.
+	 * Run a CRC check from the tail to the head. We can't just check
+	 * MAX_ICLOGS records past the tail because the tail may point to stale
+	 * blocks cleared during the search for the head/tail. These blocks are
+	 * overwritten with zero-length records and thus record count is not a
+	 * reliable indicator of the iclog state before a crash.
 	 */
-	if (count < XLOG_MAX_ICLOGS + 1)
-		tmp_head = head_blk;
-
-	/*
-	 * We now have a tail and temporary head block that covers at least
-	 * XLOG_MAX_ICLOGS records from the tail. We need to verify that these
-	 * records were completely written. Run a CRC verification pass from
-	 * tail to head and return the result.
-	 */
-	error = xlog_do_recovery_pass(log, tmp_head, tail_blk,
+	first_bad = 0;
+	error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
 				      XLOG_RECOVER_CRCPASS, &first_bad);
+	while (error == -EFSBADCRC && first_bad) {
+		int	tail_distance;
+
+		/*
+		 * Is corruption within range of the head? If so, retry from
+		 * the next record. Otherwise return an error.
+		 */
+		tail_distance = xlog_tail_distance(log, head_blk, first_bad);
+		if (tail_distance > BTOBB(XLOG_MAX_ICLOGS * hsize))
+			break;
 
+		/* skip to the next record; returns positive count on success */
+		error = xlog_seek_logrec_hdr(log, head_blk, first_bad, 2, bp,
+				&tmp_tail, &thead, &wrapped);
+		if (error < 0)
+			goto out;
+
+		*tail_blk = tmp_tail;
+		first_bad = 0;
+		error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
+					      XLOG_RECOVER_CRCPASS, &first_bad);
+	}
+
+	if (!error && *tail_blk != orig_tail)
+		xfs_warn(log->l_mp,
+		"Tail block (0x%llx) overwrite detected. Updated to 0x%llx",
+			 orig_tail, *tail_blk);
 out:
 	xlog_put_bp(bp);
 	return error;
@@ -1187,7 +1232,8 @@ xlog_verify_head(
 	if (error)
 		return error;
 
-	return xlog_verify_tail(log, *head_blk, *tail_blk);
+	return xlog_verify_tail(log, *head_blk, tail_blk,
+				be32_to_cpu((*rhead)->h_size));
 }
 
 /*
-- 
2.14.1

[PATCH 29/47] xfs: handle -EFSCORRUPTED during head/tail verification

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit a4c9b34d6a17081005ec459b57b8effc08f4c731 upstream.

Torn write and tail overwrite detection both trigger only on
-EFSBADCRC errors. While this is the most likely failure scenario
for each condition, -EFSCORRUPTED is still possible in certain cases
depending on what ends up on disk when a torn write or partial tail
overwrite occurs. For example, an invalid log record h_len can lead
to an -EFSCORRUPTED error when running the log recovery CRC pass.

Therefore, update log head and tail verification to trigger the
associated head/tail fixups in the event of -EFSCORRUPTED errors
along with -EFSBADCRC. Also, -EFSCORRUPTED can currently be returned
from xlog_do_recovery_pass() before rhead_blk is initialized if the
first record encountered happens to be corrupted. This leads to an
incorrect 'first_bad' return value. Initialize rhead_blk earlier in
the function to address that problem as well.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log_recover.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index fdad8c9ecbb3..83e90bf1899f 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -1102,7 +1102,7 @@ xlog_verify_tail(
 	first_bad = 0;
 	error = xlog_do_recovery_pass(log, head_blk, *tail_blk,
 				      XLOG_RECOVER_CRCPASS, &first_bad);
-	while (error == -EFSBADCRC && first_bad) {
+	while ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
 		int	tail_distance;
 
 		/*
@@ -1188,7 +1188,7 @@ xlog_verify_head(
 	 */
 	error = xlog_do_recovery_pass(log, *head_blk, tmp_rhead_blk,
 				      XLOG_RECOVER_CRCPASS, &first_bad);
-	if (error == -EFSBADCRC) {
+	if ((error == -EFSBADCRC || error == -EFSCORRUPTED) && first_bad) {
 		/*
 		 * We've hit a potential torn write. Reset the error and warn
 		 * about it.
@@ -5255,7 +5255,7 @@ xlog_do_recovery_pass(
 	LIST_HEAD		(buffer_list);
 
 	ASSERT(head_blk != tail_blk);
-	rhead_blk = 0;
+	blk_no = rhead_blk = tail_blk;
 
 	for (i = 0; i < XLOG_RHASH_SIZE; i++)
 		INIT_HLIST_HEAD(&rhash[i]);
@@ -5333,7 +5333,6 @@ xlog_do_recovery_pass(
 	}
 
 	memset(rhash, 0, sizeof(rhash));
-	blk_no = rhead_blk = tail_blk;
 	if (tail_blk > head_blk) {
 		/*
 		 * Perform recovery around the end of the physical log.
-- 
2.14.1

[PATCH 30/47] xfs: add log recovery tracepoint for head/tail

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit e67d3d4246e5fbb0c7c700426d11241ca9c6f473 upstream.

Torn write detection and tail overwrite detection can shift the log
head and tail respectively in the event of CRC mismatch or
corruption errors. Add a high-level log recovery tracepoint to dump
the final log head/tail and make those values easily attainable in
debug/diagnostic situations.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log_recover.c |  2 ++
 fs/xfs/xfs_trace.h       | 18 ++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 83e90bf1899f..edd849b8f14d 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -5596,6 +5596,8 @@ xlog_do_recover(
 	xfs_buf_t	*bp;
 	xfs_sb_t	*sbp;
 
+	trace_xfs_log_recover(log, head_blk, tail_blk);
+
 	/*
 	 * First replay the images in the log.
 	 */
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 2df73f3a73c1..6221c3818c6e 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -1991,6 +1991,24 @@ DEFINE_EVENT(xfs_swap_extent_class, name, \
 DEFINE_SWAPEXT_EVENT(xfs_swap_extent_before);
 DEFINE_SWAPEXT_EVENT(xfs_swap_extent_after);
 
+TRACE_EVENT(xfs_log_recover,
+	TP_PROTO(struct xlog *log, xfs_daddr_t headblk, xfs_daddr_t tailblk),
+	TP_ARGS(log, headblk, tailblk),
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(xfs_daddr_t, headblk)
+		__field(xfs_daddr_t, tailblk)
+	),
+	TP_fast_assign(
+		__entry->dev = log->l_mp->m_super->s_dev;
+		__entry->headblk = headblk;
+		__entry->tailblk = tailblk;
+	),
+	TP_printk("dev %d:%d headblk 0x%llx tailblk 0x%llx",
+		  MAJOR(__entry->dev), MINOR(__entry->dev), __entry->headblk,
+		  __entry->tailblk)
+)
+
 TRACE_EVENT(xfs_log_recover_record,
 	TP_PROTO(struct xlog *log, struct xlog_rec_header *rhead, int pass),
 	TP_ARGS(log, rhead, pass),
-- 
2.14.1

[PATCH 31/47] xfs: stop searching for free slots in an inode chunk when there are none

[Christoph Hellwig]

From: Carlos Maiolino <cmaiolino@redhat.com>

commit 2d32311cf19bfb8c1d2b4601974ddd951f9cfd0b upstream.

In a filesystem without finobt, the Space manager selects an AG to alloc a new
inode, where xfs_dialloc_ag_inobt() will search the AG for the free slot chunk.

When the new inode is in the same AG as its parent, the btree will be searched
starting on the parent's record, and then retried from the top if no slot is
available beyond the parent's record.

To exit this loop though, xfs_dialloc_ag_inobt() relies on the fact that the
btree must have a free slot available, once its callers relied on the
agi->freecount when deciding how/where to allocate this new inode.

In the case when the agi->freecount is corrupted, showing available inodes in an
AG, when in fact there is none, this becomes an infinite loop.

Add a way to stop the loop when a free slot is not found in the btree, making
the function to fall into the whole AG scan which will then, be able to detect
the corruption and shut the filesystem down.

As pointed by Brian, this might impact performance, giving the fact we
don't reset the search distance anymore when we reach the end of the
tree, giving it fewer tries before falling back to the whole AG search, but
it will only affect searches that start within 10 records to the end of the tree.

Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_ialloc.c | 55 +++++++++++++++++++++++-----------------------
 1 file changed, 27 insertions(+), 28 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index af6acd5f276c..4536ac588fa3 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -1123,6 +1123,7 @@ xfs_dialloc_ag_inobt(
 	int			error;
 	int			offset;
 	int			i, j;
+	int			searchdistance = 10;
 
 	pag = xfs_perag_get(mp, agno);
 
@@ -1149,7 +1150,6 @@ xfs_dialloc_ag_inobt(
 	if (pagno == agno) {
 		int		doneleft;	/* done, to the left */
 		int		doneright;	/* done, to the right */
-		int		searchdistance = 10;
 
 		error = xfs_inobt_lookup(cur, pagino, XFS_LOOKUP_LE, &i);
 		if (error)
@@ -1210,21 +1210,9 @@ xfs_dialloc_ag_inobt(
 		/*
 		 * Loop until we find an inode chunk with a free inode.
 		 */
-		while (!doneleft || !doneright) {
+		while (--searchdistance > 0 && (!doneleft || !doneright)) {
 			int	useleft;  /* using left inode chunk this time */
 
-			if (!--searchdistance) {
-				/*
-				 * Not in range - save last search
-				 * location and allocate a new inode
-				 */
-				xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
-				pag->pagl_leftrec = trec.ir_startino;
-				pag->pagl_rightrec = rec.ir_startino;
-				pag->pagl_pagino = pagino;
-				goto newino;
-			}
-
 			/* figure out the closer block if both are valid. */
 			if (!doneleft && !doneright) {
 				useleft = pagino -
@@ -1268,26 +1256,37 @@ xfs_dialloc_ag_inobt(
 				goto error1;
 		}
 
-		/*
-		 * We've reached the end of the btree. because
-		 * we are only searching a small chunk of the
-		 * btree each search, there is obviously free
-		 * inodes closer to the parent inode than we
-		 * are now. restart the search again.
-		 */
-		pag->pagl_pagino = NULLAGINO;
-		pag->pagl_leftrec = NULLAGINO;
-		pag->pagl_rightrec = NULLAGINO;
-		xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
-		xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
-		goto restart_pagno;
+		if (searchdistance <= 0) {
+			/*
+			 * Not in range - save last search
+			 * location and allocate a new inode
+			 */
+			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
+			pag->pagl_leftrec = trec.ir_startino;
+			pag->pagl_rightrec = rec.ir_startino;
+			pag->pagl_pagino = pagino;
+
+		} else {
+			/*
+			 * We've reached the end of the btree. because
+			 * we are only searching a small chunk of the
+			 * btree each search, there is obviously free
+			 * inodes closer to the parent inode than we
+			 * are now. restart the search again.
+			 */
+			pag->pagl_pagino = NULLAGINO;
+			pag->pagl_leftrec = NULLAGINO;
+			pag->pagl_rightrec = NULLAGINO;
+			xfs_btree_del_cursor(tcur, XFS_BTREE_NOERROR);
+			xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+			goto restart_pagno;
+		}
 	}
 
 	/*
 	 * In a different AG from the parent.
 	 * See if the most recently allocated block has any free.
 	 */
-newino:
 	if (agi->agi_newino != cpu_to_be32(NULLAGINO)) {
 		error = xfs_inobt_lookup(cur, be32_to_cpu(agi->agi_newino),
 					 XFS_LOOKUP_EQ, &i);
-- 
2.14.1

[PATCH 32/47] xfs: evict all inodes involved with log redo item

[Christoph Hellwig]

From: "Darrick J. Wong" <darrick.wong@oracle.com>

commit 799ea9e9c59949008770aab4e1da87f10e99dbe4 upstream.

When we introduced the bmap redo log items, we set MS_ACTIVE on the
mountpoint and XFS_IRECOVERY on the inode to prevent unlinked inodes
from being truncated prematurely during log recovery.  This also had the
effect of putting linked inodes on the lru instead of evicting them.

Unfortunately, we neglected to find all those unreferenced lru inodes
and evict them after finishing log recovery, which means that we leak
them if anything goes wrong in the rest of xfs_mountfs, because the lru
is only cleaned out on unmount.

Therefore, evict unreferenced inodes in the lru list immediately
after clearing MS_ACTIVE.

Fixes: 17c12bcd30 ("xfs: when replaying bmap operations, don't let unlinked inodes get reaped")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: viro@ZenIV.linux.org.uk
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
 fs/inode.c         |  1 +
 fs/internal.h      |  1 -
 fs/xfs/xfs_log.c   | 12 ++++++++++++
 include/linux/fs.h |  1 +
 4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/fs/inode.c b/fs/inode.c
index 88110fd0b282..920aa0b1c6b0 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -637,6 +637,7 @@ void evict_inodes(struct super_block *sb)
 
 	dispose_list(&dispose);
 }
+EXPORT_SYMBOL_GPL(evict_inodes);
 
 /**
  * invalidate_inodes	- attempt to free all inodes on a superblock
diff --git a/fs/internal.h b/fs/internal.h
index f4da3341b4a3..8b7143b0211c 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -136,7 +136,6 @@ extern bool atime_needs_update_rcu(const struct path *, struct inode *);
 extern void inode_io_list_del(struct inode *inode);
 
 extern long get_nr_dirty_inodes(void);
-extern void evict_inodes(struct super_block *);
 extern int invalidate_inodes(struct super_block *, bool);
 
 /*
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index ebe20f1591f1..fe5f3df8b253 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -761,12 +761,24 @@ xfs_log_mount_finish(
 	 * inodes.  Turn it off immediately after recovery finishes
 	 * so that we don't leak the quota inodes if subsequent mount
 	 * activities fail.
+	 *
+	 * We let all inodes involved in redo item processing end up on
+	 * the LRU instead of being evicted immediately so that if we do
+	 * something to an unlinked inode, the irele won't cause
+	 * premature truncation and freeing of the inode, which results
+	 * in log recovery failure.  We have to evict the unreferenced
+	 * lru inodes after clearing MS_ACTIVE because we don't
+	 * otherwise clean up the lru if there's a subsequent failure in
+	 * xfs_mountfs, which leads to us leaking the inodes if nothing
+	 * else (e.g. quotacheck) references the inodes before the
+	 * mount failure occurs.
 	 */
 	mp->m_super->s_flags |= MS_ACTIVE;
 	error = xlog_recover_finish(mp->m_log);
 	if (!error)
 		xfs_log_work_queue(mp);
 	mp->m_super->s_flags &= ~MS_ACTIVE;
+	evict_inodes(mp->m_super);
 
 	if (readonly)
 		mp->m_flags |= XFS_MOUNT_RDONLY;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index dd88ded27fc8..d705ae084edd 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2760,6 +2760,7 @@ static inline void lockdep_annotate_inode_mutex_key(struct inode *inode) { };
 #endif
 extern void unlock_new_inode(struct inode *);
 extern unsigned int get_next_ino(void);
+extern void evict_inodes(struct super_block *sb);
 
 extern void __iget(struct inode * inode);
 extern void iget_failed(struct inode *);
-- 
2.14.1

[PATCH 33/47] xfs: check for race with xfs_reclaim_inode() in xfs_ifree_cluster()

[Christoph Hellwig]

From: Omar Sandoval <osandov@fb.com>

commit f2e9ad212def50bcf4c098c6288779dd97fff0f0 upstream.

After xfs_ifree_cluster() finds an inode in the radix tree and verifies
that the inode number is what it expected, xfs_reclaim_inode() can swoop
in and free it. xfs_ifree_cluster() will then happily continue working
on the freed inode. Most importantly, it will mark the inode stale,
which will probably be overwritten when the inode slab object is
reallocated, but if it has already been reallocated then we can end up
with an inode spuriously marked stale.

In 8a17d7ddedb4 ("xfs: mark reclaimed inodes invalid earlier") we added
a second check to xfs_iflush_cluster() to detect this race, but the
similar RCU lookup in xfs_ifree_cluster() needs the same treatment.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_icache.c | 10 +++++-----
 fs/xfs/xfs_inode.c  | 23 ++++++++++++++++++-----
 2 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index e279882de427..86a4911520cc 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -1078,11 +1078,11 @@ xfs_reclaim_inode(
 	 * Because we use RCU freeing we need to ensure the inode always appears
 	 * to be reclaimed with an invalid inode number when in the free state.
 	 * We do this as early as possible under the ILOCK so that
-	 * xfs_iflush_cluster() can be guaranteed to detect races with us here.
-	 * By doing this, we guarantee that once xfs_iflush_cluster has locked
-	 * XFS_ILOCK that it will see either a valid, flushable inode that will
-	 * serialise correctly, or it will see a clean (and invalid) inode that
-	 * it can skip.
+	 * xfs_iflush_cluster() and xfs_ifree_cluster() can be guaranteed to
+	 * detect races with us here. By doing this, we guarantee that once
+	 * xfs_iflush_cluster() or xfs_ifree_cluster() has locked XFS_ILOCK that
+	 * it will see either a valid inode that will serialise correctly, or it
+	 * will see an invalid inode that it can skip.
 	 */
 	spin_lock(&ip->i_flags_lock);
 	ip->i_flags = XFS_IRECLAIM;
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 98cd905eadca..9e795ab08a53 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -2368,11 +2368,24 @@ xfs_ifree_cluster(
 			 * already marked stale. If we can't lock it, back off
 			 * and retry.
 			 */
-			if (ip != free_ip &&
-			    !xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
-				rcu_read_unlock();
-				delay(1);
-				goto retry;
+			if (ip != free_ip) {
+				if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
+					rcu_read_unlock();
+					delay(1);
+					goto retry;
+				}
+
+				/*
+				 * Check the inode number again in case we're
+				 * racing with freeing in xfs_reclaim_inode().
+				 * See the comments in that function for more
+				 * information as to why the initial check is
+				 * not sufficient.
+				 */
+				if (ip->i_ino != inum + i) {
+					xfs_iunlock(ip, XFS_ILOCK_EXCL);
+					continue;
+				}
 			}
 			rcu_read_unlock();
 
-- 
2.14.1

[PATCH 34/47] xfs: open-code xfs_buf_item_dirty()

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit a4f6cf6b2b6b60ec2a05a33a32e65caa4149aa2b upstream.

It checks a single flag and has one caller. It probably isn't worth
its own function.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf_item.c  | 11 -----------
 fs/xfs/xfs_buf_item.h  |  1 -
 fs/xfs/xfs_trans_buf.c |  2 +-
 3 files changed, 1 insertion(+), 13 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index 573fc72c3f23..cdae0ad5e0a5 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -945,17 +945,6 @@ xfs_buf_item_log(
 }
 
 
-/*
- * Return 1 if the buffer has been logged or ordered in a transaction (at any
- * point, not just the current transaction) and 0 if not.
- */
-uint
-xfs_buf_item_dirty(
-	xfs_buf_log_item_t	*bip)
-{
-	return (bip->bli_flags & XFS_BLI_DIRTY);
-}
-
 STATIC void
 xfs_buf_item_free(
 	xfs_buf_log_item_t	*bip)
diff --git a/fs/xfs/xfs_buf_item.h b/fs/xfs/xfs_buf_item.h
index 530686e1afb9..e0e744aefaa8 100644
--- a/fs/xfs/xfs_buf_item.h
+++ b/fs/xfs/xfs_buf_item.h
@@ -64,7 +64,6 @@ typedef struct xfs_buf_log_item {
 int	xfs_buf_item_init(struct xfs_buf *, struct xfs_mount *);
 void	xfs_buf_item_relse(struct xfs_buf *);
 void	xfs_buf_item_log(xfs_buf_log_item_t *, uint, uint);
-uint	xfs_buf_item_dirty(xfs_buf_log_item_t *);
 void	xfs_buf_attach_iodone(struct xfs_buf *,
 			      void(*)(struct xfs_buf *, xfs_log_item_t *),
 			      xfs_log_item_t *);
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index 86987d823d76..cac8abbeca3f 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -435,7 +435,7 @@ xfs_trans_brelse(xfs_trans_t	*tp,
 	if (XFS_FORCED_SHUTDOWN(tp->t_mountp) && freed) {
 		xfs_trans_ail_remove(&bip->bli_item, SHUTDOWN_LOG_IO_ERROR);
 		xfs_buf_item_relse(bp);
-	} else if (!xfs_buf_item_dirty(bip)) {
+	} else if (!(bip->bli_flags & XFS_BLI_DIRTY)) {
 /***
 		ASSERT(bp->b_pincount == 0);
 ***/
-- 
2.14.1

[PATCH 35/47] xfs: remove unnecessary dirty bli format check for ordered bufs

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 6453c65d3576bc3e602abb5add15f112755c08ca upstream.

xfs_buf_item_unlock() historically checked the dirty state of the
buffer by manually checking the buffer log formats for dirty
segments. The introduction of ordered buffers invalidated this check
because ordered buffers have dirty bli's but no dirty (logged)
segments. The check was updated to accommodate ordered buffers by
looking at the bli state first and considering the blf only if the
bli is clean.

This logic is safe but unnecessary. There is no valid case where the
bli is clean yet the blf has dirty segments. The bli is set dirty
whenever the blf is logged (via xfs_trans_log_buf()) and the blf is
cleared in the only place BLI_DIRTY is cleared (xfs_trans_binval()).

Remove the conditional blf dirty checks and replace with an assert
that should catch any discrepencies between bli and blf dirty
states. Refactor the old blf dirty check into a helper function to
be used by the assert.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf_item.c | 62 ++++++++++++++++++++++++++-------------------------
 fs/xfs/xfs_buf_item.h |  1 +
 2 files changed, 33 insertions(+), 30 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index cdae0ad5e0a5..ff076d11804a 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -575,26 +575,18 @@ xfs_buf_item_unlock(
 {
 	struct xfs_buf_log_item	*bip = BUF_ITEM(lip);
 	struct xfs_buf		*bp = bip->bli_buf;
-	bool			clean;
-	bool			aborted;
-	int			flags;
+	bool			aborted = !!(lip->li_flags & XFS_LI_ABORTED);
+	bool			hold = !!(bip->bli_flags & XFS_BLI_HOLD);
+	bool			dirty = !!(bip->bli_flags & XFS_BLI_DIRTY);
+	bool			ordered = !!(bip->bli_flags & XFS_BLI_ORDERED);
 
 	/* Clear the buffer's association with this transaction. */
 	bp->b_transp = NULL;
 
 	/*
-	 * If this is a transaction abort, don't return early.  Instead, allow
-	 * the brelse to happen.  Normally it would be done for stale
-	 * (cancelled) buffers at unpin time, but we'll never go through the
-	 * pin/unpin cycle if we abort inside commit.
+	 * The per-transaction state has been copied above so clear it from the
+	 * bli.
 	 */
-	aborted = (lip->li_flags & XFS_LI_ABORTED) ? true : false;
-	/*
-	 * Before possibly freeing the buf item, copy the per-transaction state
-	 * so we can reference it safely later after clearing it from the
-	 * buffer log item.
-	 */
-	flags = bip->bli_flags;
 	bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_HOLD | XFS_BLI_ORDERED);
 
 	/*
@@ -602,7 +594,7 @@ xfs_buf_item_unlock(
 	 * unlock the buffer and free the buf item when the buffer is unpinned
 	 * for the last time.
 	 */
-	if (flags & XFS_BLI_STALE) {
+	if (bip->bli_flags & XFS_BLI_STALE) {
 		trace_xfs_buf_item_unlock_stale(bip);
 		ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL);
 		if (!aborted) {
@@ -620,20 +612,11 @@ xfs_buf_item_unlock(
 	 * regardless of whether it is dirty or not. A dirty abort implies a
 	 * shutdown, anyway.
 	 *
-	 * Ordered buffers are dirty but may have no recorded changes, so ensure
-	 * we only release clean items here.
+	 * The bli dirty state should match whether the blf has logged segments
+	 * except for ordered buffers, where only the bli should be dirty.
 	 */
-	clean = (flags & XFS_BLI_DIRTY) ? false : true;
-	if (clean) {
-		int i;
-		for (i = 0; i < bip->bli_format_count; i++) {
-			if (!xfs_bitmap_empty(bip->bli_formats[i].blf_data_map,
-				     bip->bli_formats[i].blf_map_size)) {
-				clean = false;
-				break;
-			}
-		}
-	}
+	ASSERT((!ordered && dirty == xfs_buf_item_dirty_format(bip)) ||
+	       (ordered && dirty && !xfs_buf_item_dirty_format(bip)));
 
 	/*
 	 * Clean buffers, by definition, cannot be in the AIL. However, aborted
@@ -652,11 +635,11 @@ xfs_buf_item_unlock(
 			ASSERT(XFS_FORCED_SHUTDOWN(lip->li_mountp));
 			xfs_trans_ail_remove(lip, SHUTDOWN_LOG_IO_ERROR);
 			xfs_buf_item_relse(bp);
-		} else if (clean)
+		} else if (!dirty)
 			xfs_buf_item_relse(bp);
 	}
 
-	if (!(flags & XFS_BLI_HOLD))
+	if (!hold)
 		xfs_buf_relse(bp);
 }
 
@@ -945,6 +928,25 @@ xfs_buf_item_log(
 }
 
 
+/*
+ * Return true if the buffer has any ranges logged/dirtied by a transaction,
+ * false otherwise.
+ */
+bool
+xfs_buf_item_dirty_format(
+	struct xfs_buf_log_item	*bip)
+{
+	int			i;
+
+	for (i = 0; i < bip->bli_format_count; i++) {
+		if (!xfs_bitmap_empty(bip->bli_formats[i].blf_data_map,
+			     bip->bli_formats[i].blf_map_size))
+			return true;
+	}
+
+	return false;
+}
+
 STATIC void
 xfs_buf_item_free(
 	xfs_buf_log_item_t	*bip)
diff --git a/fs/xfs/xfs_buf_item.h b/fs/xfs/xfs_buf_item.h
index e0e744aefaa8..9690ce62c9a7 100644
--- a/fs/xfs/xfs_buf_item.h
+++ b/fs/xfs/xfs_buf_item.h
@@ -64,6 +64,7 @@ typedef struct xfs_buf_log_item {
 int	xfs_buf_item_init(struct xfs_buf *, struct xfs_mount *);
 void	xfs_buf_item_relse(struct xfs_buf *);
 void	xfs_buf_item_log(xfs_buf_log_item_t *, uint, uint);
+bool	xfs_buf_item_dirty_format(struct xfs_buf_log_item *);
 void	xfs_buf_attach_iodone(struct xfs_buf *,
 			      void(*)(struct xfs_buf *, xfs_log_item_t *),
 			      xfs_log_item_t *);
-- 
2.14.1

[PATCH 36/47] xfs: ordered buffer log items are never formatted

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit e9385cc6fb7edf23702de33a2dc82965d92d9392 upstream.

Ordered buffers pass through the logging infrastructure without ever
being written to the log. The way this works is that the ordered
buffer status is transferred to the log vector at commit time via
the ->iop_size() callback. In xlog_cil_insert_format_items(),
ordered log vectors bypass ->iop_format() processing altogether.

Therefore it is unnecessary for xfs_buf_item_format() to handle
ordered buffers. Remove the unnecessary logic and assert that an
ordered buffer never reaches this point.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_buf_item.c | 12 ++----------
 fs/xfs/xfs_trace.h    |  1 -
 2 files changed, 2 insertions(+), 11 deletions(-)

diff --git a/fs/xfs/xfs_buf_item.c b/fs/xfs/xfs_buf_item.c
index ff076d11804a..ef2c1375f092 100644
--- a/fs/xfs/xfs_buf_item.c
+++ b/fs/xfs/xfs_buf_item.c
@@ -323,6 +323,8 @@ xfs_buf_item_format(
 	ASSERT((bip->bli_flags & XFS_BLI_STALE) ||
 	       (xfs_blft_from_flags(&bip->__bli_format) > XFS_BLFT_UNKNOWN_BUF
 	        && xfs_blft_from_flags(&bip->__bli_format) < XFS_BLFT_MAX_BUF));
+	ASSERT(!(bip->bli_flags & XFS_BLI_ORDERED) ||
+	       (bip->bli_flags & XFS_BLI_STALE));
 
 
 	/*
@@ -347,16 +349,6 @@ xfs_buf_item_format(
 		bip->bli_flags &= ~XFS_BLI_INODE_BUF;
 	}
 
-	if ((bip->bli_flags & (XFS_BLI_ORDERED|XFS_BLI_STALE)) ==
-							XFS_BLI_ORDERED) {
-		/*
-		 * The buffer has been logged just to order it.  It is not being
-		 * included in the transaction commit, so don't format it.
-		 */
-		trace_xfs_buf_item_format_ordered(bip);
-		return;
-	}
-
 	for (i = 0; i < bip->bli_format_count; i++) {
 		xfs_buf_item_format_segment(bip, lv, &vecp, offset,
 					    &bip->bli_formats[i]);
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 6221c3818c6e..bdf69e1c7410 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -520,7 +520,6 @@ DEFINE_BUF_ITEM_EVENT(xfs_buf_item_size);
 DEFINE_BUF_ITEM_EVENT(xfs_buf_item_size_ordered);
 DEFINE_BUF_ITEM_EVENT(xfs_buf_item_size_stale);
 DEFINE_BUF_ITEM_EVENT(xfs_buf_item_format);
-DEFINE_BUF_ITEM_EVENT(xfs_buf_item_format_ordered);
 DEFINE_BUF_ITEM_EVENT(xfs_buf_item_format_stale);
 DEFINE_BUF_ITEM_EVENT(xfs_buf_item_ordered);
 DEFINE_BUF_ITEM_EVENT(xfs_buf_item_pin);
-- 
2.14.1

[PATCH 37/47] xfs: refactor buffer logging into buffer dirtying helper

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 9684010d38eccda733b61106765e9357cf436f65 upstream.

xfs_trans_log_buf() is responsible for logging the dirty segments of
a buffer along with setting all of the necessary state on the
transaction, buffer, bli, etc., to ensure that the associated items
are marked as dirty and prepared for I/O. We have a couple use cases
that need to to dirty a buffer in a transaction without actually
logging dirty ranges of the buffer.  One existing use case is
ordered buffers, which are currently logged with arbitrary ranges to
accomplish this even though the content of ordered buffers is never
written to the log. Another pending use case is to relog an already
dirty buffer across rolled transactions within the deferred
operations infrastructure. This is required to prevent a held
(XFS_BLI_HOLD) buffer from pinning the tail of the log.

Refactor xfs_trans_log_buf() into a new function that contains all
of the logic responsible to dirty the transaction, lidp, buffer and
bli. This new function can be used in the future for the use cases
outlined above. This patch does not introduce functional changes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_trans.h     |  4 +++-
 fs/xfs/xfs_trans_buf.c | 46 ++++++++++++++++++++++++++++++----------------
 2 files changed, 33 insertions(+), 17 deletions(-)

diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 0318e92aed66..40555bcaa277 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -222,7 +222,9 @@ void		xfs_trans_dquot_buf(xfs_trans_t *, struct xfs_buf *, uint);
 void		xfs_trans_inode_alloc_buf(xfs_trans_t *, struct xfs_buf *);
 void		xfs_trans_ichgtime(struct xfs_trans *, struct xfs_inode *, int);
 void		xfs_trans_ijoin(struct xfs_trans *, struct xfs_inode *, uint);
-void		xfs_trans_log_buf(xfs_trans_t *, struct xfs_buf *, uint, uint);
+void		xfs_trans_log_buf(struct xfs_trans *, struct xfs_buf *, uint,
+				  uint);
+void		xfs_trans_dirty_buf(struct xfs_trans *, struct xfs_buf *);
 void		xfs_trans_log_inode(xfs_trans_t *, struct xfs_inode *, uint);
 
 void		xfs_extent_free_init_defer_op(void);
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index cac8abbeca3f..8c99813e5377 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -493,25 +493,17 @@ xfs_trans_bhold_release(xfs_trans_t	*tp,
 }
 
 /*
- * This is called to mark bytes first through last inclusive of the given
- * buffer as needing to be logged when the transaction is committed.
- * The buffer must already be associated with the given transaction.
- *
- * First and last are numbers relative to the beginning of this buffer,
- * so the first byte in the buffer is numbered 0 regardless of the
- * value of b_blkno.
+ * Mark a buffer dirty in the transaction.
  */
 void
-xfs_trans_log_buf(xfs_trans_t	*tp,
-		  xfs_buf_t	*bp,
-		  uint		first,
-		  uint		last)
+xfs_trans_dirty_buf(
+	struct xfs_trans	*tp,
+	struct xfs_buf		*bp)
 {
-	xfs_buf_log_item_t	*bip = bp->b_fspriv;
+	struct xfs_buf_log_item	*bip = bp->b_fspriv;
 
 	ASSERT(bp->b_transp == tp);
 	ASSERT(bip != NULL);
-	ASSERT(first <= last && last < BBTOB(bp->b_length));
 	ASSERT(bp->b_iodone == NULL ||
 	       bp->b_iodone == xfs_buf_iodone_callbacks);
 
@@ -531,8 +523,6 @@ xfs_trans_log_buf(xfs_trans_t	*tp,
 	bp->b_iodone = xfs_buf_iodone_callbacks;
 	bip->bli_item.li_cb = xfs_buf_iodone;
 
-	trace_xfs_trans_log_buf(bip);
-
 	/*
 	 * If we invalidated the buffer within this transaction, then
 	 * cancel the invalidation now that we're dirtying the buffer
@@ -545,15 +535,39 @@ xfs_trans_log_buf(xfs_trans_t	*tp,
 		bp->b_flags &= ~XBF_STALE;
 		bip->__bli_format.blf_flags &= ~XFS_BLF_CANCEL;
 	}
+	bip->bli_flags |= XFS_BLI_DIRTY | XFS_BLI_LOGGED;
 
 	tp->t_flags |= XFS_TRANS_DIRTY;
 	bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
+}
+
+/*
+ * This is called to mark bytes first through last inclusive of the given
+ * buffer as needing to be logged when the transaction is committed.
+ * The buffer must already be associated with the given transaction.
+ *
+ * First and last are numbers relative to the beginning of this buffer,
+ * so the first byte in the buffer is numbered 0 regardless of the
+ * value of b_blkno.
+ */
+void
+xfs_trans_log_buf(
+	struct xfs_trans	*tp,
+	struct xfs_buf		*bp,
+	uint			first,
+	uint			last)
+{
+	struct xfs_buf_log_item	*bip = bp->b_fspriv;
+
+	ASSERT(first <= last && last < BBTOB(bp->b_length));
+
+	xfs_trans_dirty_buf(tp, bp);
 
 	/*
 	 * If we have an ordered buffer we are not logging any dirty range but
 	 * it still needs to be marked dirty and that it has been logged.
 	 */
-	bip->bli_flags |= XFS_BLI_DIRTY | XFS_BLI_LOGGED;
+	trace_xfs_trans_log_buf(bip);
 	if (!(bip->bli_flags & XFS_BLI_ORDERED))
 		xfs_buf_item_log(bip, first, last);
 }
-- 
2.14.1

[PATCH 38/47] xfs: don't log dirty ranges for ordered buffers

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 8dc518dfa7dbd079581269e51074b3c55a65a880 upstream.

Ordered buffers are attached to transactions and pushed through the
logging infrastructure just like normal buffers with the exception
that they are not actually written to the log. Therefore, we don't
need to log dirty ranges of ordered buffers. xfs_trans_log_buf() is
called on ordered buffers to set up all of the dirty state on the
transaction, buffer and log item and prepare the buffer for I/O.

Now that xfs_trans_dirty_buf() is available, call it from
xfs_trans_ordered_buf() so the latter is now mutually exclusive with
xfs_trans_log_buf(). This reflects the implementation of ordered
buffers and helps eliminate confusion over the need to log ranges of
ordered buffers just to set up internal log state.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_btree.c  |  6 ++----
 fs/xfs/libxfs/xfs_ialloc.c |  2 --
 fs/xfs/xfs_trans_buf.c     | 26 ++++++++++++++------------
 3 files changed, 16 insertions(+), 18 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index e9f26a09a0be..69c3f428b582 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -4447,12 +4447,10 @@ xfs_btree_block_change_owner(
 	 * though, so everything is consistent in memory.
 	 */
 	if (bp) {
-		if (cur->bc_tp) {
+		if (cur->bc_tp)
 			xfs_trans_ordered_buf(cur->bc_tp, bp);
-			xfs_btree_log_block(cur, bp, XFS_BB_OWNER);
-		} else {
+		else
 			xfs_buf_delwri_queue(bp, bbcoi->buffer_list);
-		}
 	} else {
 		ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
 		ASSERT(level == cur->bc_nlevels - 1);
diff --git a/fs/xfs/libxfs/xfs_ialloc.c b/fs/xfs/libxfs/xfs_ialloc.c
index 4536ac588fa3..42fef0731e2a 100644
--- a/fs/xfs/libxfs/xfs_ialloc.c
+++ b/fs/xfs/libxfs/xfs_ialloc.c
@@ -368,8 +368,6 @@ xfs_ialloc_inode_init(
 				 * transaction and pin the log appropriately.
 				 */
 				xfs_trans_ordered_buf(tp, fbuf);
-				xfs_trans_log_buf(tp, fbuf, 0,
-						  BBTOB(fbuf->b_length) - 1);
 			}
 		} else {
 			fbuf->b_flags |= XBF_DONE;
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index 8c99813e5377..3089e8015369 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -560,16 +560,12 @@ xfs_trans_log_buf(
 	struct xfs_buf_log_item	*bip = bp->b_fspriv;
 
 	ASSERT(first <= last && last < BBTOB(bp->b_length));
+	ASSERT(!(bip->bli_flags & XFS_BLI_ORDERED));
 
 	xfs_trans_dirty_buf(tp, bp);
 
-	/*
-	 * If we have an ordered buffer we are not logging any dirty range but
-	 * it still needs to be marked dirty and that it has been logged.
-	 */
 	trace_xfs_trans_log_buf(bip);
-	if (!(bip->bli_flags & XFS_BLI_ORDERED))
-		xfs_buf_item_log(bip, first, last);
+	xfs_buf_item_log(bip, first, last);
 }
 
 
@@ -722,12 +718,11 @@ xfs_trans_inode_alloc_buf(
 }
 
 /*
- * Mark the buffer as ordered for this transaction. This means
- * that the contents of the buffer are not recorded in the transaction
- * but it is tracked in the AIL as though it was. This allows us
- * to record logical changes in transactions rather than the physical
- * changes we make to the buffer without changing writeback ordering
- * constraints of metadata buffers.
+ * Mark the buffer as ordered for this transaction. This means that the contents
+ * of the buffer are not recorded in the transaction but it is tracked in the
+ * AIL as though it was. This allows us to record logical changes in
+ * transactions rather than the physical changes we make to the buffer without
+ * changing writeback ordering constraints of metadata buffers.
  */
 void
 xfs_trans_ordered_buf(
@@ -739,9 +734,16 @@ xfs_trans_ordered_buf(
 	ASSERT(bp->b_transp == tp);
 	ASSERT(bip != NULL);
 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
+	ASSERT(!xfs_buf_item_dirty_format(bip));
 
 	bip->bli_flags |= XFS_BLI_ORDERED;
 	trace_xfs_buf_item_ordered(bip);
+
+	/*
+	 * We don't log a dirty range of an ordered buffer but it still needs
+	 * to be marked dirty and that it has been logged.
+	 */
+	xfs_trans_dirty_buf(tp, bp);
 }
 
 /*
-- 
2.14.1

[PATCH 39/47] xfs: skip bmbt block ino validation during owner change

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 99c794c639a65cc7b74f30a674048fd100fe9ac8 upstream.

Extent swap uses xfs_btree_visit_blocks() to fix up bmbt block
owners on v5 (!rmapbt) filesystems. The bmbt scan uses
xfs_btree_lookup_get_block() to read bmbt blocks which verifies the
current owner of the block against the parent inode of the bmbt.
This works during extent swap because the bmbt owners are updated to
the opposite inode number before the inode extent forks are swapped.

The modified bmbt blocks are marked as ordered buffers which allows
everything to commit in a single transaction. If the transaction
commits to the log and the system crashes such that recovery of the
extent swap is required, log recovery restarts the bmbt scan to fix
up any bmbt blocks that may have not been written back before the
crash. The log recovery bmbt scan occurs after the inode forks have
been swapped, however. This causes the bmbt block owner verification
to fail, leads to log recovery failure and requires xfs_repair to
zap the log to recover.

Define a new invalid inode owner flag to inform the btree block
lookup mechanism that the current inode may be invalid with respect
to the current owner of the bmbt block. Set this flag on the cursor
used for change owner scans to allow this operation to work at
runtime and during log recovery.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Fixes: bb3be7e7c ("xfs: check for bogus values in btree block headers")
Cc: stable@vger.kernel.org
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_bmap_btree.c | 1 +
 fs/xfs/libxfs/xfs_btree.c      | 1 +
 fs/xfs/libxfs/xfs_btree.h      | 3 ++-
 3 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/libxfs/xfs_bmap_btree.c b/fs/xfs/libxfs/xfs_bmap_btree.c
index 5c3918678bb6..9968a746c649 100644
--- a/fs/xfs/libxfs/xfs_bmap_btree.c
+++ b/fs/xfs/libxfs/xfs_bmap_btree.c
@@ -888,6 +888,7 @@ xfs_bmbt_change_owner(
 	cur = xfs_bmbt_init_cursor(ip->i_mount, tp, ip, whichfork);
 	if (!cur)
 		return -ENOMEM;
+	cur->bc_private.b.flags |= XFS_BTCUR_BPRV_INVALID_OWNER;
 
 	error = xfs_btree_change_owner(cur, new_owner, buffer_list);
 	xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 69c3f428b582..1df747fadc3a 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -1774,6 +1774,7 @@ xfs_btree_lookup_get_block(
 
 	/* Check the inode owner since the verifiers don't. */
 	if (xfs_sb_version_hascrc(&cur->bc_mp->m_sb) &&
+	    !(cur->bc_private.b.flags & XFS_BTCUR_BPRV_INVALID_OWNER) &&
 	    (cur->bc_flags & XFS_BTREE_LONG_PTRS) &&
 	    be64_to_cpu((*blkp)->bb_u.l.bb_owner) !=
 			cur->bc_private.b.ip->i_ino)
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index 3b0fc1afada5..33c7be2357b9 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -268,7 +268,8 @@ typedef struct xfs_btree_cur
 			short		forksize;	/* fork's inode space */
 			char		whichfork;	/* data or attr fork */
 			char		flags;		/* flags */
-#define	XFS_BTCUR_BPRV_WASDEL	1			/* was delayed */
+#define	XFS_BTCUR_BPRV_WASDEL		(1<<0)		/* was delayed */
+#define	XFS_BTCUR_BPRV_INVALID_OWNER	(1<<1)		/* for ext swap */
 		} b;
 	}		bc_private;	/* per-btree type data */
 } xfs_btree_cur_t;
-- 
2.14.1

[PATCH 40/47] xfs: move bmbt owner change to last step of extent swap

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 6fb10d6d22094bc4062f92b9ccbcee2f54033d04 upstream.

The extent swap operation currently resets bmbt block owners before
the inode forks are swapped. The bmbt buffers are marked as ordered
so they do not have to be physically logged in the transaction.

This use of ordered buffers is not safe as bmbt buffers may have
been previously physically logged. The bmbt owner change algorithm
needs to be updated to physically log buffers that are already dirty
when/if they are encountered. This means that an extent swap will
eventually require multiple rolling transactions to handle large
btrees. In addition, all inode related changes must be logged before
the bmbt owner change scan begins and can roll the transaction for
the first time to preserve fs consistency via log recovery.

In preparation for such fixes to the bmbt owner change algorithm,
refactor the bmbt scan out of the extent fork swap code to the last
operation before the transaction is committed. Update
xfs_swap_extent_forks() to only set the inode log flags when an
owner change scan is necessary. Update xfs_swap_extents() to trigger
the owner change based on the inode log flags. Note that since the
owner change now occurs after the extent fork swap, the inode btrees
must be fixed up with the inode number of the current inode (similar
to log recovery).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_bmap_util.c | 44 ++++++++++++++++++++++++++------------------
 1 file changed, 26 insertions(+), 18 deletions(-)

diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 87b495e2f15a..15cd36f29fc4 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1825,29 +1825,18 @@ xfs_swap_extent_forks(
 	}
 
 	/*
-	 * Before we've swapped the forks, lets set the owners of the forks
-	 * appropriately. We have to do this as we are demand paging the btree
-	 * buffers, and so the validation done on read will expect the owner
-	 * field to be correctly set. Once we change the owners, we can swap the
-	 * inode forks.
+	 * Btree format (v3) inodes have the inode number stamped in the bmbt
+	 * block headers. We can't start changing the bmbt blocks until the
+	 * inode owner change is logged so recovery does the right thing in the
+	 * event of a crash. Set the owner change log flags now and leave the
+	 * bmbt scan as the last step.
 	 */
 	if (ip->i_d.di_version == 3 &&
-	    ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
+	    ip->i_d.di_format == XFS_DINODE_FMT_BTREE)
 		(*target_log_flags) |= XFS_ILOG_DOWNER;
-		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK,
-					      tip->i_ino, NULL);
-		if (error)
-			return error;
-	}
-
 	if (tip->i_d.di_version == 3 &&
-	    tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
+	    tip->i_d.di_format == XFS_DINODE_FMT_BTREE)
 		(*src_log_flags) |= XFS_ILOG_DOWNER;
-		error = xfs_bmbt_change_owner(tp, tip, XFS_DATA_FORK,
-					      ip->i_ino, NULL);
-		if (error)
-			return error;
-	}
 
 	/*
 	 * Swap the data forks of the inodes
@@ -2076,6 +2065,25 @@ xfs_swap_extents(
 	xfs_trans_log_inode(tp, ip,  src_log_flags);
 	xfs_trans_log_inode(tp, tip, target_log_flags);
 
+	/*
+	 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems
+	 * have inode number owner values in the bmbt blocks that still refer to
+	 * the old inode. Scan each bmbt to fix up the owner values with the
+	 * inode number of the current inode.
+	 */
+	if (src_log_flags & XFS_ILOG_DOWNER) {
+		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK,
+					      ip->i_ino, NULL);
+		if (error)
+			goto out_trans_cancel;
+	}
+	if (target_log_flags & XFS_ILOG_DOWNER) {
+		error = xfs_bmbt_change_owner(tp, tip, XFS_DATA_FORK,
+					      tip->i_ino, NULL);
+		if (error)
+			goto out_trans_cancel;
+	}
+
 	/*
 	 * If this is a synchronous mount, make sure that the
 	 * transaction goes to disk before returning to the user.
-- 
2.14.1

[PATCH 41/47] xfs: disallow marking previously dirty buffers as ordered

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit a5814bceea48ee1c57c4db2bd54b0c0246daf54a upstream.

Ordered buffers are used in situations where the buffer is not
physically logged but must pass through the transaction/logging
pipeline for a particular transaction. As a result, ordered buffers
are not unpinned and written back until the transaction commits to
the log. Ordered buffers have a strict requirement that the target
buffer must not be currently dirty and resident in the log pipeline
at the time it is marked ordered. If a dirty+ordered buffer is
committed, the buffer is reinserted to the AIL but not physically
relogged at the LSN of the associated checkpoint. The buffer log
item is assigned the LSN of the latest checkpoint and the AIL
effectively releases the previously logged buffer content from the
active log before the buffer has been written back. If the tail
pushes forward and a filesystem crash occurs while in this state, an
inconsistent filesystem could result.

It is currently the caller responsibility to ensure an ordered
buffer is not already dirty from a previous modification. This is
unclear and error prone when not used in situations where it is
guaranteed a buffer has not been previously modified (such as new
metadata allocations).

To facilitate general purpose use of ordered buffers, update
xfs_trans_ordered_buf() to conditionally order the buffer based on
state of the log item and return the status of the result. If the
bli is dirty, do not order the buffer and return false. The caller
must either physically log the buffer (having acquired the
appropriate log reservation) or push it from the AIL to clean it
before it can be marked ordered in the current transaction.

Note that ordered buffers are currently only used in two situations:
1.) inode chunk allocation where previously logged buffers are not
possible and 2.) extent swap which will be updated to handle ordered
buffer failures in a separate patch.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_trans.h     | 2 +-
 fs/xfs/xfs_trans_buf.c | 7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 40555bcaa277..5669cf00bae0 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -217,7 +217,7 @@ void		xfs_trans_bhold_release(xfs_trans_t *, struct xfs_buf *);
 void		xfs_trans_binval(xfs_trans_t *, struct xfs_buf *);
 void		xfs_trans_inode_buf(xfs_trans_t *, struct xfs_buf *);
 void		xfs_trans_stale_inode_buf(xfs_trans_t *, struct xfs_buf *);
-void		xfs_trans_ordered_buf(xfs_trans_t *, struct xfs_buf *);
+bool		xfs_trans_ordered_buf(xfs_trans_t *, struct xfs_buf *);
 void		xfs_trans_dquot_buf(xfs_trans_t *, struct xfs_buf *, uint);
 void		xfs_trans_inode_alloc_buf(xfs_trans_t *, struct xfs_buf *);
 void		xfs_trans_ichgtime(struct xfs_trans *, struct xfs_inode *, int);
diff --git a/fs/xfs/xfs_trans_buf.c b/fs/xfs/xfs_trans_buf.c
index 3089e8015369..3ba7a96a8abd 100644
--- a/fs/xfs/xfs_trans_buf.c
+++ b/fs/xfs/xfs_trans_buf.c
@@ -724,7 +724,7 @@ xfs_trans_inode_alloc_buf(
  * transactions rather than the physical changes we make to the buffer without
  * changing writeback ordering constraints of metadata buffers.
  */
-void
+bool
 xfs_trans_ordered_buf(
 	struct xfs_trans	*tp,
 	struct xfs_buf		*bp)
@@ -734,7 +734,9 @@ xfs_trans_ordered_buf(
 	ASSERT(bp->b_transp == tp);
 	ASSERT(bip != NULL);
 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
-	ASSERT(!xfs_buf_item_dirty_format(bip));
+
+	if (xfs_buf_item_dirty_format(bip))
+		return false;
 
 	bip->bli_flags |= XFS_BLI_ORDERED;
 	trace_xfs_buf_item_ordered(bip);
@@ -744,6 +746,7 @@ xfs_trans_ordered_buf(
 	 * to be marked dirty and that it has been logged.
 	 */
 	xfs_trans_dirty_buf(tp, bp);
+	return true;
 }
 
 /*
-- 
2.14.1

[PATCH 42/47] xfs: relog dirty buffers during swapext bmbt owner change

[Christoph Hellwig]

From: Brian Foster <bfoster@redhat.com>

commit 2dd3d709fc4338681a3aa61658122fa8faa5a437 upstream.

The owner change bmbt scan that occurs during extent swap operations
does not handle ordered buffer failures. Buffers that cannot be
marked ordered must be physically logged so previously dirty ranges
of the buffer can be relogged in the transaction.

Since the bmbt scan may need to process and potentially log a large
number of blocks, we can't expect to complete this operation in a
single transaction. Update extent swap to use a permanent
transaction with enough log reservation to physically log a buffer.
Update the bmbt scan to physically log any buffers that cannot be
ordered and to terminate the scan with -EAGAIN. On -EAGAIN, the
caller rolls the transaction and restarts the scan. Finally, update
the bmbt scan helper function to skip bmbt blocks that already match
the expected owner so they are not reprocessed after scan restarts.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[darrick: fix the xfs_trans_roll call]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_btree.c | 26 ++++++++++++++-------
 fs/xfs/xfs_bmap_util.c    | 59 ++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 66 insertions(+), 19 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 1df747fadc3a..4ad1e214b1b2 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -4435,10 +4435,15 @@ xfs_btree_block_change_owner(
 
 	/* modify the owner */
 	block = xfs_btree_get_block(cur, level, &bp);
-	if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+	if (cur->bc_flags & XFS_BTREE_LONG_PTRS) {
+		if (block->bb_u.l.bb_owner == cpu_to_be64(bbcoi->new_owner))
+			return 0;
 		block->bb_u.l.bb_owner = cpu_to_be64(bbcoi->new_owner);
-	else
+	} else {
+		if (block->bb_u.s.bb_owner == cpu_to_be32(bbcoi->new_owner))
+			return 0;
 		block->bb_u.s.bb_owner = cpu_to_be32(bbcoi->new_owner);
+	}
 
 	/*
 	 * If the block is a root block hosted in an inode, we might not have a
@@ -4447,14 +4452,19 @@ xfs_btree_block_change_owner(
 	 * block is formatted into the on-disk inode fork. We still change it,
 	 * though, so everything is consistent in memory.
 	 */
-	if (bp) {
-		if (cur->bc_tp)
-			xfs_trans_ordered_buf(cur->bc_tp, bp);
-		else
-			xfs_buf_delwri_queue(bp, bbcoi->buffer_list);
-	} else {
+	if (!bp) {
 		ASSERT(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE);
 		ASSERT(level == cur->bc_nlevels - 1);
+		return 0;
+	}
+
+	if (cur->bc_tp) {
+		if (!xfs_trans_ordered_buf(cur->bc_tp, bp)) {
+			xfs_btree_log_block(cur, bp, XFS_BB_OWNER);
+			return -EAGAIN;
+		}
+	} else {
+		xfs_buf_delwri_queue(bp, bbcoi->buffer_list);
 	}
 
 	return 0;
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index 15cd36f29fc4..5ffefac081f7 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1914,6 +1914,48 @@ xfs_swap_extent_forks(
 	return 0;
 }
 
+/*
+ * Fix up the owners of the bmbt blocks to refer to the current inode. The
+ * change owner scan attempts to order all modified buffers in the current
+ * transaction. In the event of ordered buffer failure, the offending buffer is
+ * physically logged as a fallback and the scan returns -EAGAIN. We must roll
+ * the transaction in this case to replenish the fallback log reservation and
+ * restart the scan. This process repeats until the scan completes.
+ */
+static int
+xfs_swap_change_owner(
+	struct xfs_trans	**tpp,
+	struct xfs_inode	*ip,
+	struct xfs_inode	*tmpip)
+{
+	int			error;
+	struct xfs_trans	*tp = *tpp;
+
+	do {
+		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino,
+					      NULL);
+		/* success or fatal error */
+		if (error != -EAGAIN)
+			break;
+
+		error = xfs_trans_roll(tpp, NULL);
+		if (error)
+			break;
+		tp = *tpp;
+
+		/*
+		 * Redirty both inodes so they can relog and keep the log tail
+		 * moving forward.
+		 */
+		xfs_trans_ijoin(tp, ip, 0);
+		xfs_trans_ijoin(tp, tmpip, 0);
+		xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+		xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE);
+	} while (true);
+
+	return error;
+}
+
 int
 xfs_swap_extents(
 	struct xfs_inode	*ip,	/* target inode */
@@ -1927,8 +1969,8 @@ xfs_swap_extents(
 	int			error = 0;
 	int			lock_flags;
 	struct xfs_ifork	*cowfp;
-	__uint64_t		f;
-	int			resblks;
+	uint64_t		f;
+	int			resblks = 0;
 
 	/*
 	 * Lock the inodes against other IO, page faults and truncate to
@@ -1976,11 +2018,8 @@ xfs_swap_extents(
 			  XFS_SWAP_RMAP_SPACE_RES(mp,
 				XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK),
 				XFS_DATA_FORK);
-		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks,
-				0, 0, &tp);
-	} else
-		error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0,
-				0, 0, &tp);
+	}
+	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
 	if (error)
 		goto out_unlock;
 
@@ -2072,14 +2111,12 @@ xfs_swap_extents(
 	 * inode number of the current inode.
 	 */
 	if (src_log_flags & XFS_ILOG_DOWNER) {
-		error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK,
-					      ip->i_ino, NULL);
+		error = xfs_swap_change_owner(&tp, ip, tip);
 		if (error)
 			goto out_trans_cancel;
 	}
 	if (target_log_flags & XFS_ILOG_DOWNER) {
-		error = xfs_bmbt_change_owner(tp, tip, XFS_DATA_FORK,
-					      tip->i_ino, NULL);
+		error = xfs_swap_change_owner(&tp, tip, ip);
 		if (error)
 			goto out_trans_cancel;
 	}
-- 
2.14.1

[PATCH 43/47] xfs: disable per-inode DAX flag

[Christoph Hellwig]

commit 742d84290739ae908f1b61b7d17ea382c8c0073a upstream.

Currently flag switching can be used to easily crash the kernel.  Disable
the per-inode DAX flag until that is sorted out.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_ioctl.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 73cfc7179124..be54216027b6 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1005,11 +1005,12 @@ xfs_diflags_to_linux(
 		inode->i_flags |= S_NOATIME;
 	else
 		inode->i_flags &= ~S_NOATIME;
+#if 0	/* disabled until the flag switching races are sorted out */
 	if (xflags & FS_XFLAG_DAX)
 		inode->i_flags |= S_DAX;
 	else
 		inode->i_flags &= ~S_DAX;
-
+#endif
 }
 
 static int
-- 
2.14.1

[PATCH 44/47] xfs: fix incorrect log_flushed on fsync

[Christoph Hellwig]

From: Amir Goldstein <amir73il@gmail.com>

commit 47c7d0b19502583120c3f396c7559e7a77288a68 upstream.

When calling into _xfs_log_force{,_lsn}() with a pointer
to log_flushed variable, log_flushed will be set to 1 if:
1. xlog_sync() is called to flush the active log buffer
AND/OR
2. xlog_wait() is called to wait on a syncing log buffers

xfs_file_fsync() checks the value of log_flushed after
_xfs_log_force_lsn() call to optimize away an explicit
PREFLUSH request to the data block device after writing
out all the file's pages to disk.

This optimization is incorrect in the following sequence of events:

 Task A                    Task B
 -------------------------------------------------------
 xfs_file_fsync()
   _xfs_log_force_lsn()
     xlog_sync()
        [submit PREFLUSH]
                           xfs_file_fsync()
                             file_write_and_wait_range()
                               [submit WRITE X]
                               [endio  WRITE X]
                             _xfs_log_force_lsn()
                               xlog_wait()
        [endio  PREFLUSH]

The write X is not guarantied to be on persistent storage
when PREFLUSH request in completed, because write A was submitted
after the PREFLUSH request, but xfs_file_fsync() of task A will
be notified of log_flushed=1 and will skip explicit flush.

If the system crashes after fsync of task A, write X may not be
present on disk after reboot.

This bug was discovered and demonstrated using Josef Bacik's
dm-log-writes target, which can be used to record block io operations
and then replay a subset of these operations onto the target device.
The test goes something like this:
- Use fsx to execute ops of a file and record ops on log device
- Every now and then fsync the file, store md5 of file and mark
  the location in the log
- Then replay log onto device for each mark, mount fs and compare
  md5 of file to stored value

Cc: Christoph Hellwig <hch@lst.de>
Cc: Josef Bacik <jbacik@fb.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index fe5f3df8b253..33c9a3aae948 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -3337,8 +3337,6 @@ _xfs_log_force(
 		 */
 		if (iclog->ic_state & XLOG_STATE_IOERROR)
 			return -EIO;
-		if (log_flushed)
-			*log_flushed = 1;
 	} else {
 
 no_sleep:
@@ -3442,8 +3440,6 @@ _xfs_log_force_lsn(
 
 				xlog_wait(&iclog->ic_prev->ic_write_wait,
 							&log->l_icloglock);
-				if (log_flushed)
-					*log_flushed = 1;
 				already_slept = 1;
 				goto try_again;
 			}
@@ -3477,9 +3473,6 @@ _xfs_log_force_lsn(
 			 */
 			if (iclog->ic_state & XLOG_STATE_IOERROR)
 				return -EIO;
-
-			if (log_flushed)
-				*log_flushed = 1;
 		} else {		/* just return */
 			spin_unlock(&log->l_icloglock);
 		}
-- 
2.14.1

[PATCH 45/47] xfs: don't set v3 xflags for v2 inodes

[Christoph Hellwig]

commit dd60687ee541ca3f6df8758f38e6f22f57c42a37 upstream.

Reject attempts to set XFLAGS that correspond to di_flags2 inode flags
if the inode isn't a v3 inode, because di_flags2 only exists on v3.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_ioctl.c | 38 +++++++++++++++++++++++++-------------
 1 file changed, 25 insertions(+), 13 deletions(-)

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index be54216027b6..bce2e260f55e 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -928,16 +928,15 @@ xfs_ioc_fsgetxattr(
 	return 0;
 }
 
-STATIC void
-xfs_set_diflags(
+STATIC uint16_t
+xfs_flags2diflags(
 	struct xfs_inode	*ip,
 	unsigned int		xflags)
 {
-	unsigned int		di_flags;
-	uint64_t		di_flags2;
-
 	/* can't set PREALLOC this way, just preserve it */
-	di_flags = (ip->i_d.di_flags & XFS_DIFLAG_PREALLOC);
+	uint16_t		di_flags =
+		(ip->i_d.di_flags & XFS_DIFLAG_PREALLOC);
+
 	if (xflags & FS_XFLAG_IMMUTABLE)
 		di_flags |= XFS_DIFLAG_IMMUTABLE;
 	if (xflags & FS_XFLAG_APPEND)
@@ -967,19 +966,24 @@ xfs_set_diflags(
 		if (xflags & FS_XFLAG_EXTSIZE)
 			di_flags |= XFS_DIFLAG_EXTSIZE;
 	}
-	ip->i_d.di_flags = di_flags;
 
-	/* diflags2 only valid for v3 inodes. */
-	if (ip->i_d.di_version < 3)
-		return;
+	return di_flags;
+}
+
+STATIC uint64_t
+xfs_flags2diflags2(
+	struct xfs_inode	*ip,
+	unsigned int		xflags)
+{
+	uint64_t		di_flags2 =
+		(ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK);
 
-	di_flags2 = (ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK);
 	if (xflags & FS_XFLAG_DAX)
 		di_flags2 |= XFS_DIFLAG2_DAX;
 	if (xflags & FS_XFLAG_COWEXTSIZE)
 		di_flags2 |= XFS_DIFLAG2_COWEXTSIZE;
 
-	ip->i_d.di_flags2 = di_flags2;
+	return di_flags2;
 }
 
 STATIC void
@@ -1020,6 +1024,7 @@ xfs_ioctl_setattr_xflags(
 	struct fsxattr		*fa)
 {
 	struct xfs_mount	*mp = ip->i_mount;
+	uint64_t		di_flags2;
 
 	/* Can't change realtime flag if any extents are allocated. */
 	if ((ip->i_d.di_nextents || ip->i_delayed_blks) &&
@@ -1050,7 +1055,14 @@ xfs_ioctl_setattr_xflags(
 	    !capable(CAP_LINUX_IMMUTABLE))
 		return -EPERM;
 
-	xfs_set_diflags(ip, fa->fsx_xflags);
+	/* diflags2 only valid for v3 inodes. */
+	di_flags2 = xfs_flags2diflags2(ip, fa->fsx_xflags);
+	if (di_flags2 && ip->i_d.di_version < 3)
+		return -EINVAL;
+
+	ip->i_d.di_flags = xfs_flags2diflags(ip, fa->fsx_xflags);
+	ip->i_d.di_flags2 = di_flags2;
+
 	xfs_diflags_to_linux(ip);
 	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
-- 
2.14.1

[PATCH 46/47] xfs: open code end_buffer_async_write in xfs_finish_page_writeback

[Christoph Hellwig]

commit 8353a814f2518dcfa79a5bb77afd0e7dfa391bb1 upstream.

Our loop in xfs_finish_page_writeback, which iterates over all buffer
heads in a page and then calls end_buffer_async_write, which also
iterates over all buffers in the page to check if any I/O is in flight
is not only inefficient, but also potentially dangerous as
end_buffer_async_write can cause the page and all buffers to be freed.

Replace it with a single loop that does the work of end_buffer_async_write
on a per-page basis.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_aops.c | 72 ++++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 48 insertions(+), 24 deletions(-)

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index f750d888bd17..d23889e0bedc 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -90,11 +90,11 @@ xfs_find_bdev_for_inode(
  * associated buffer_heads, paying attention to the start and end offsets that
  * we need to process on the page.
  *
- * Landmine Warning: bh->b_end_io() will call end_page_writeback() on the last
- * buffer in the IO. Once it does this, it is unsafe to access the bufferhead or
- * the page at all, as we may be racing with memory reclaim and it can free both
- * the bufferhead chain and the page as it will see the page as clean and
- * unused.
+ * Note that we open code the action in end_buffer_async_write here so that we
+ * only have to iterate over the buffers attached to the page once.  This is not
+ * only more efficient, but also ensures that we only calls end_page_writeback
+ * at the end of the iteration, and thus avoids the pitfall of having the page
+ * and buffers potentially freed after every call to end_buffer_async_write.
  */
 static void
 xfs_finish_page_writeback(
@@ -102,29 +102,45 @@ xfs_finish_page_writeback(
 	struct bio_vec		*bvec,
 	int			error)
 {
-	unsigned int		end = bvec->bv_offset + bvec->bv_len - 1;
-	struct buffer_head	*head, *bh, *next;
+	struct buffer_head	*head = page_buffers(bvec->bv_page), *bh = head;
+	bool			busy = false;
 	unsigned int		off = 0;
-	unsigned int		bsize;
+	unsigned long		flags;
 
 	ASSERT(bvec->bv_offset < PAGE_SIZE);
 	ASSERT((bvec->bv_offset & (i_blocksize(inode) - 1)) == 0);
-	ASSERT(end < PAGE_SIZE);
+	ASSERT(bvec->bv_offset + bvec->bv_len <= PAGE_SIZE);
 	ASSERT((bvec->bv_len & (i_blocksize(inode) - 1)) == 0);
 
-	bh = head = page_buffers(bvec->bv_page);
-
-	bsize = bh->b_size;
+	local_irq_save(flags);
+	bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
 	do {
-		if (off > end)
-			break;
-		next = bh->b_this_page;
-		if (off < bvec->bv_offset)
-			goto next_bh;
-		bh->b_end_io(bh, !error);
-next_bh:
-		off += bsize;
-	} while ((bh = next) != head);
+		if (off >= bvec->bv_offset &&
+		    off < bvec->bv_offset + bvec->bv_len) {
+			ASSERT(buffer_async_write(bh));
+			ASSERT(bh->b_end_io == NULL);
+
+			if (error) {
+				mapping_set_error(bvec->bv_page->mapping, -EIO);
+				set_buffer_write_io_error(bh);
+				clear_buffer_uptodate(bh);
+				SetPageError(bvec->bv_page);
+			} else {
+				set_buffer_uptodate(bh);
+			}
+			clear_buffer_async_write(bh);
+			unlock_buffer(bh);
+		} else if (buffer_async_write(bh)) {
+			ASSERT(buffer_locked(bh));
+			busy = true;
+		}
+		off += bh->b_size;
+	} while ((bh = bh->b_this_page) != head);
+	bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
+	local_irq_restore(flags);
+
+	if (!busy)
+		end_page_writeback(bvec->bv_page);
 }
 
 /*
@@ -138,8 +154,10 @@ xfs_destroy_ioend(
 	int			error)
 {
 	struct inode		*inode = ioend->io_inode;
-	struct bio		*last = ioend->io_bio;
-	struct bio		*bio, *next;
+	struct bio		*bio = &ioend->io_inline_bio;
+	struct bio		*last = ioend->io_bio, *next;
+	u64			start = bio->bi_iter.bi_sector;
+	bool			quiet = bio_flagged(bio, BIO_QUIET);
 
 	for (bio = &ioend->io_inline_bio; bio; bio = next) {
 		struct bio_vec	*bvec;
@@ -160,6 +178,11 @@ xfs_destroy_ioend(
 
 		bio_put(bio);
 	}
+
+	if (unlikely(error && !quiet)) {
+		xfs_err_ratelimited(XFS_I(inode)->i_mount,
+			"writeback error on sector %llu", start);
+	}
 }
 
 /*
@@ -427,7 +450,8 @@ xfs_start_buffer_writeback(
 	ASSERT(!buffer_delay(bh));
 	ASSERT(!buffer_unwritten(bh));
 
-	mark_buffer_async_write(bh);
+	bh->b_end_io = NULL;
+	set_buffer_async_write(bh);
 	set_buffer_uptodate(bh);
 	clear_buffer_dirty(bh);
 }
-- 
2.14.1

[PATCH 47/47] xfs: use kmem_free to free return value of kmem_zalloc

[Christoph Hellwig]

From: Pan Bian <bianpan2016@163.com>

commit 6c370590cfe0c36bcd62d548148aa65c984540b7 upstream.

In function xfs_test_remount_options(), kfree() is used to free memory
allocated by kmem_zalloc(). But it is better to use kmem_free().

Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_super.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 882fb8524fcb..67d589e0a49f 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1214,7 +1214,7 @@ xfs_test_remount_options(
 	tmp_mp->m_super = sb;
 	error = xfs_parseargs(tmp_mp, options);
 	xfs_free_fsname(tmp_mp);
-	kfree(tmp_mp);
+	kmem_free(tmp_mp);
 
 	return error;
 }
-- 
2.14.1

Re: 4.9-stable updates for XFS

[Greg KH]

On Sun, Sep 17, 2017 at 02:06:25PM -0700, Christoph Hellwig wrote:
> Hi all,
> 
> below are backports up to 4.14-rc1 for XFS.  I've selected all
> clear bugfixes for reported bugs, and a few harmless prep patches
> that allow us to carry late bug fixes as-is instead of providing
> special versions for -stable, which in the past have caused more
> harm than good.
> 
> In addition to the patches for 4.13-stable there also are various
> patches that are in 4.13 but not in 4.9-stable yet.

Thanks for all of these, now queued up.

greg k-h

4.9-stable updates for XFS

[Christoph Hellwig]

Hi all,

below are backports up to 4.14-rc5 for XFS.

Re: 4.9-stable updates for XFS

[Greg KH]

On Thu, Oct 19, 2017 at 04:22:43PM +0200, Christoph Hellwig wrote:
> Hi all,
> 
> below are backports up to 4.14-rc5 for XFS.

All now applied, thanks.

greg k-h

4.9-stable updates for XFS

[Christoph Hellwig]

Hi all,

below are backports up to (almost) 4.12-rc4 for XFS.  I've selected all
clear bugfixes for reported bugs.  In addition to the patches in
4.11-stable there also are 3 patches that are in 4.11 but not in
4.9-stable yet at the beginning of the series.

4.9-stable updates for XFS

[Christoph Hellwig]

Hi all,

below are backports up to 4.11-rc4 for XFS.  I've selected all clear
bugfixes for reported bugs.  In addition to the patches in 4.10-stable
there also are 2 patches that are in 4.10 but not in 4.9-stable yet
at the beginning of the series.

Re: 4.9-stable updates for XFS

[Greg KH]

On Sat, Apr 01, 2017 at 08:39:59AM +0200, Christoph Hellwig wrote:
> Hi all,
> 
> below are backports up to 4.11-rc4 for XFS.  I've selected all clear
> bugfixes for reported bugs.  In addition to the patches in 4.10-stable
> there also are 2 patches that are in 4.10 but not in 4.9-stable yet
> at the beginning of the series.

All now applied, thanks for the series.

greg k-h

4.9-stable updates for XFS

[Christoph Hellwig]

Hi all,

below are backports up to 4.10-rc6 for XFS.  I've selected all clear
bugfixes for reported bugs.  I've skipped the finobt space reservation
patch for now - I think it is stable material, but I want it to settle
a bit more first.

Re: 4.9-stable updates for XFS

[Greg KH]

On Thu, Feb 02, 2017 at 08:55:52AM +0100, Christoph Hellwig wrote:
> Hi all,
> 
> below are backports up to 4.10-rc6 for XFS.  I've selected all clear
> bugfixes for reported bugs.  I've skipped the finobt space reservation
> patch for now - I think it is stable material, but I want it to settle
> a bit more first.

Thanks for all of these, now all applied.

greg k-h

Re: 4.9-stable updates for XFS

[Eric Sandeen]

On 2/2/17 1:55 AM, Christoph Hellwig wrote:
> Hi all,
> 
> below are backports up to 4.10-rc6 for XFS.  I've selected all clear
> bugfixes for reported bugs.  I've skipped the finobt space reservation
> patch for now - I think it is stable material, but I want it to settle
> a bit more first.

fwiw, the finobt space reservation thing also seems to be doing something
odd with allocation on striped storage, unless I'm missing something.

If I stick an xfs_bmap -v into generic/108 after we write the initial
file, we find that it's not stripe aligned with that patch in place,
which seems unexpected.  I haven't yet worked out why, was first trying
to sort out that lvm error propagation problem...

-Eric

Re: 4.9-stable updates for XFS

[Eric Sandeen]

On 2/2/17 10:00 AM, Eric Sandeen wrote:
> On 2/2/17 1:55 AM, Christoph Hellwig wrote:
>> Hi all,
>>
>> below are backports up to 4.10-rc6 for XFS.  I've selected all clear
>> bugfixes for reported bugs.  I've skipped the finobt space reservation
>> patch for now - I think it is stable material, but I want it to settle
>> a bit more first.
> 
> fwiw, the finobt space reservation thing also seems to be doing something
> odd with allocation on striped storage, unless I'm missing something.
> 
> If I stick an xfs_bmap -v into generic/108 after we write the initial
> file, we find that it's not stripe aligned with that patch in place,
> which seems unexpected.  I haven't yet worked out why, was first trying
> to sort out that lvm error propagation problem...

Ok, I guess this may not be a big deal.  Because this is a small filesystem
in the test, and striped, we end up with small AGs:

meta-data=/dev/mapper/vg_108-lv_108 isize=512    agcount=9, agsize=7168 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=0, rmapbt=0, reflink=0
data     =                       bsize=4096   blocks=63488, imaxpct=25
         =                       sunit=1024   swidth=2048 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =/dev/sdb3              bsize=4096   blocks=32768, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

each only 7168 blocks, or about 28M.

We try to do a 16M write, and xfs would like that to be stripe aligned.
I'm not quite sure why it's failing, but for a larger filesystem things
do come out aligned again.  I'll keep digging but I don't think there's
any fundamental problem here, this is a weird, small filesystem.

-Eric

4.9-stable updates for XFS

[Christoph Hellwig]

Hi all,

below are backports from 4.10-rc3 for XFS.  I've selected all clear
bugfixes for reported bugs, and added about a handful of small
infrastructure backports so that we can take the fixes as is instead of
having to redo them in a different way than upstream.

These have passed xfstests on top of Linux 4.9.2.  Even if some of the 
patches might apply to older stable trees please do not backport them 
unless someone volunteers to QA them first.

Re: 4.9-stable updates for XFS

[Darrick J. Wong]

On Mon, Jan 09, 2017 at 04:38:31PM +0100, Christoph Hellwig wrote:
> Hi all,
> 
> below are backports from 4.10-rc3 for XFS.  I've selected all clear
> bugfixes for reported bugs, and added about a handful of small
> infrastructure backports so that we can take the fixes as is instead of
> having to redo them in a different way than upstream.
> 
> These have passed xfstests on top of Linux 4.9.2.  Even if some of the 
> patches might apply to older stable trees please do not backport them 
> unless someone volunteers to QA them first.

FWIW the list looks reasonable to me.

--D

> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: 4.9-stable updates for XFS

[Greg KH]

On Mon, Jan 09, 2017 at 04:38:31PM +0100, Christoph Hellwig wrote:
> Hi all,
> 
> below are backports from 4.10-rc3 for XFS.  I've selected all clear
> bugfixes for reported bugs, and added about a handful of small
> infrastructure backports so that we can take the fixes as is instead of
> having to redo them in a different way than upstream.
> 
> These have passed xfstests on top of Linux 4.9.2.  Even if some of the 
> patches might apply to older stable trees please do not backport them 
> unless someone volunteers to QA them first.

Many thanks for these, all now queued up.

greg k-h