[PATCH] fadvise volatile fixes from Dmitry

[John Stultz <john.stultz@linaro.org>]

On 03/16/2012 03:51 PM, John Stultz wrote:
> This patch provides new fadvise flags that can be used to mark
> file pages as volatile, which will allow it to be discarded if the
> kernel wants to reclaim memory.
Right after sending this I realized I had forgotten to include
some fixes for issues Dmitry pointed out. So I've included them
here.

Signed-off-by: John Stultz<john.stultz@linaro.org>
---
  mm/volatile.c |    5 +++--
  1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/volatile.c b/mm/volatile.c
index e412a8b..f40c02e 100644
--- a/mm/volatile.c
+++ b/mm/volatile.c
@@ -220,11 +220,12 @@ long mapping_range_nonvolatile(struct address_space *mapping,
  			new->mapping = mapping;
  			new->range_node.start = end + 1;
  			new->range_node.end = node->end;
-			volatile_range_resize(vrange, node->start, start-1);
+			new->purged = vrange->purged;
  			range_tree_add(&mapping->volatile_root,
  						&new->range_node);
  			if (range_on_lru(new))
  				lru_add(new);
+			volatile_range_resize(vrange, node->start, start-1);

  			break;
  		}
@@ -263,7 +264,7 @@ void mapping_clear_volatile_ranges(struct address_space *mapping)
  static int volatile_shrink(struct shrinker *ignored, struct shrink_control *sc)
  {
  	struct volatile_range *range, *next;
-	unsigned long nr_to_scan = sc->nr_to_scan;
+	s64 nr_to_scan = sc->nr_to_scan;
  	const gfp_t gfp_mask = sc->gfp_mask;

  	if (nr_to_scan&&  !(gfp_mask&  __GFP_FS))
-- 
1.7.3.2.146.gca209