Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-next

drm-intel-next-2014-01-10:
- final bits for runtime D3 on Haswell from Paul (now enabled fully)
- parse the backlight modulation freq information in the VBT from Jani
  (but not yet used)
- more watermark improvements from Ville for ilk-ivb and bdw
- bugfixes for fastboot from Jesse
- watermark fix for i830M (but not yet everything)
- vlv vga hotplug w/a (Imre)
- piles of other small improvements, cleanups and fixes all over

Note that the pull request includes a backmerge of the last drm-fixes
pulled into Linus' tree - things where getting a bit too messy. So the
shortlog also contains a bunch of patches from Linus tree. Please yell if
you want me to frob it for you a bit.

* 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel: (609 commits)
  drm/i915/bdw: make sure south port interrupts are enabled properly v2
  drm/i915: Include more information in disabled hotplug interrupt warning
  drm/i915: Only complain about a rogue hotplug IRQ after disabling
  drm/i915: Only WARN about a stuck hotplug irq ONCE
  drm/i915: s/hotplugt_status_gen4/hotplug_status_g4x/

1 files changed, 30 insertions, 0 deletions

diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index b7fc035a6943..73f3e4ee4037 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -986,6 +986,7 @@ static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
 {
 	struct file *file = iocb->ki_filp;
 	struct inode *inode = file->f_mapping->host;
+	struct address_space *mapping = inode->i_mapping;
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_holder gh;
 	int rv;
@@ -1006,6 +1007,35 @@ static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
 	if (rv != 1)
 		goto out; /* dio not valid, fall back to buffered i/o */
 
+	/*
+	 * Now since we are holding a deferred (CW) lock at this point, you
+	 * might be wondering why this is ever needed. There is a case however
+	 * where we've granted a deferred local lock against a cached exclusive
+	 * glock. That is ok provided all granted local locks are deferred, but
+	 * it also means that it is possible to encounter pages which are
+	 * cached and possibly also mapped. So here we check for that and sort
+	 * them out ahead of the dio. The glock state machine will take care of
+	 * everything else.
+	 *
+	 * If in fact the cached glock state (gl->gl_state) is deferred (CW) in
+	 * the first place, mapping->nr_pages will always be zero.
+	 */
+	if (mapping->nrpages) {
+		loff_t lstart = offset & (PAGE_CACHE_SIZE - 1);
+		loff_t len = iov_length(iov, nr_segs);
+		loff_t end = PAGE_ALIGN(offset + len) - 1;
+
+		rv = 0;
+		if (len == 0)
+			goto out;
+		if (test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
+			unmap_shared_mapping_range(ip->i_inode.i_mapping, offset, len);
+		rv = filemap_write_and_wait_range(mapping, lstart, end);
+		if (rv)
+			return rv;
+		truncate_inode_pages_range(mapping, lstart, end);
+	}
+
 	rv = __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 				  offset, nr_segs, gfs2_get_block_direct,
 				  NULL, NULL, 0);