vmscan: change shrinker API by passing shrink_control struct

Change each shrinker's API by consolidating the existing parameters into
shrink_control struct.  This will simplify any further features added w/o
touching each file of shrinker.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: fix warning]
[kosaki.motohiro@jp.fujitsu.com: fix up new shrinker API]
[akpm@linux-foundation.org: fix xfs warning]
[akpm@linux-foundation.org: update gfs2]
Signed-off-by: Ying Han <yinghan@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 14 insertions, 7 deletions

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index a2a6abb..2792a79 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1346,11 +1346,14 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
 }
 
 
-static int gfs2_shrink_glock_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
+static int gfs2_shrink_glock_memory(struct shrinker *shrink,
+				    struct shrink_control *sc)
 {
 	struct gfs2_glock *gl;
 	int may_demote;
 	int nr_skipped = 0;
+	int nr = sc->nr_to_scan;
+	gfp_t gfp_mask = sc->gfp_mask;
 	LIST_HEAD(skipped);
 
 	if (nr == 0)
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index e23d986..42e8d23 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -38,6 +38,7 @@
 
 #include <linux/sched.h>
 #include <linux/slab.h>
+#include <linux/mm.h>
 #include <linux/spinlock.h>
 #include <linux/completion.h>
 #include <linux/buffer_head.h>
@@ -77,19 +78,20 @@ static LIST_HEAD(qd_lru_list);
 static atomic_t qd_lru_count = ATOMIC_INIT(0);
 static DEFINE_SPINLOCK(qd_lru_lock);
 
-int gfs2_shrink_qd_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
+int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
 {
 	struct gfs2_quota_data *qd;
 	struct gfs2_sbd *sdp;
+	int nr_to_scan = sc->nr_to_scan;
 
-	if (nr == 0)
+	if (nr_to_scan == 0)
 		goto out;
 
-	if (!(gfp_mask & __GFP_FS))
+	if (!(sc->gfp_mask & __GFP_FS))
 		return -1;
 
 	spin_lock(&qd_lru_lock);
-	while (nr && !list_empty(&qd_lru_list)) {
+	while (nr_to_scan && !list_empty(&qd_lru_list)) {
 		qd = list_entry(qd_lru_list.next,
 				struct gfs2_quota_data, qd_reclaim);
 		sdp = qd->qd_gl->gl_sbd;
@@ -110,7 +112,7 @@ int gfs2_shrink_qd_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask)
 		spin_unlock(&qd_lru_lock);
 		kmem_cache_free(gfs2_quotad_cachep, qd);
 		spin_lock(&qd_lru_lock);
-		nr--;
+		nr_to_scan--;
 	}
 	spin_unlock(&qd_lru_lock);
 
diff --git a/fs/gfs2/quota.h b/fs/gfs2/quota.h
index e7d236c..90bf1c3 100644
--- a/fs/gfs2/quota.h
+++ b/fs/gfs2/quota.h
@@ -12,6 +12,7 @@
 
 struct gfs2_inode;
 struct gfs2_sbd;
+struct shrink_control;
 
 #define NO_QUOTA_CHANGE ((u32)-1)
 
@@ -51,7 +52,8 @@ static inline int gfs2_quota_lock_check(struct gfs2_inode *ip)
 	return ret;
 }
 
-extern int gfs2_shrink_qd_memory(struct shrinker *shrink, int nr, gfp_t gfp_mask);
+extern int gfs2_shrink_qd_memory(struct shrinker *shrink,
+				 struct shrink_control *sc);
 extern const struct quotactl_ops gfs2_quotactl_ops;
 
 #endif /* __QUOTA_DOT_H__ */