Merge tag 'v4.8-rc8' into drm-next

Linux 4.8-rc8

There was a lot of fallout in the imx/amdgpu/i915 drivers, so backmerge
it now to avoid troubles.

* tag 'v4.8-rc8': (1442 commits)
  Linux 4.8-rc8
  fault_in_multipages_readable() throws set-but-unused error
  mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing
  radix tree: fix sibling entry handling in radix_tree_descend()
  radix tree test suite: Test radix_tree_replace_slot() for multiorder entries
  fix memory leaks in tracing_buffers_splice_read()
  tracing: Move mutex to protect against resetting of seq data
  MIPS: Fix delay slot emulation count in debugfs
  MIPS: SMP: Fix possibility of deadlock when bringing CPUs online
  mm: delete unnecessary and unsafe init_tlb_ubc()
  huge tmpfs: fix Committed_AS leak
  shmem: fix tmpfs to handle the huge= option properly
  blk-mq: skip unmapped queues in blk_mq_alloc_request_hctx
  MIPS: Fix pre-r6 emulation FPU initialisation
  arm64: kgdb: handle read-only text / modules
  arm64: Call numa_store_cpu_info() earlier.
  locking/hung_task: Fix typo in CONFIG_DETECT_HUNG_TASK help text
  nvme-rdma: only clear queue flags after successful connect
  i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended
  perf/core: Limit matching exclusive events to one PMU
  ...

1 files changed, 24 insertions, 10 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 4e7b0dc22450..0b055bfb8e86 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1506,7 +1506,8 @@ static int ocfs2_zero_partial_clusters(struct inode *inode,
 				       u64 start, u64 len)
 {
 	int ret = 0;
-	u64 tmpend, end = start + len;
+	u64 tmpend = 0;
+	u64 end = start + len;
 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 	unsigned int csize = osb->s_clustersize;
 	handle_t *handle;
@@ -1538,18 +1539,31 @@ static int ocfs2_zero_partial_clusters(struct inode *inode,
 	}
 
 	/*
-	 * We want to get the byte offset of the end of the 1st cluster.
+	 * If start is on a cluster boundary and end is somewhere in another
+	 * cluster, we have not COWed the cluster starting at start, unless
+	 * end is also within the same cluster. So, in this case, we skip this
+	 * first call to ocfs2_zero_range_for_truncate() truncate and move on
+	 * to the next one.
 	 */
-	tmpend = (u64)osb->s_clustersize + (start & ~(osb->s_clustersize - 1));
-	if (tmpend > end)
-		tmpend = end;
+	if ((start & (csize - 1)) != 0) {
+		/*
+		 * We want to get the byte offset of the end of the 1st
+		 * cluster.
+		 */
+		tmpend = (u64)osb->s_clustersize +
+			(start & ~(osb->s_clustersize - 1));
+		if (tmpend > end)
+			tmpend = end;
 
-	trace_ocfs2_zero_partial_clusters_range1((unsigned long long)start,
-						 (unsigned long long)tmpend);
+		trace_ocfs2_zero_partial_clusters_range1(
+			(unsigned long long)start,
+			(unsigned long long)tmpend);
 
-	ret = ocfs2_zero_range_for_truncate(inode, handle, start, tmpend);
-	if (ret)
-		mlog_errno(ret);
+		ret = ocfs2_zero_range_for_truncate(inode, handle, start,
+						    tmpend);
+		if (ret)
+			mlog_errno(ret);
+	}
 
 	if (tmpend < end) {
 		/*