[XFS] add infrastructure for waiting on I/O completion at inode reclaim

time

SGI-PV: 934766
SGI-Modid: xfs-linux:xfs-kern:196854a

Signed-off-by: Christoph Hellwig <hch@sgi.com>
Signed-off-by: Nathan Scott <nathans@sgi.com>

1 files changed, 23 insertions, 5 deletions

diff --git a/fs/xfs/linux-2.6/xfs_vnode.c b/fs/xfs/linux-2.6/xfs_vnode.c
index 654da98de2a5..46afc86a2862 100644
--- a/fs/xfs/linux-2.6/xfs_vnode.c
+++ b/fs/xfs/linux-2.6/xfs_vnode.c
@@ -42,17 +42,33 @@ DEFINE_SPINLOCK(vnumber_lock);
  */
 #define NVSYNC                  37
 #define vptosync(v)             (&vsync[((unsigned long)v) % NVSYNC])
-sv_t vsync[NVSYNC];
+STATIC wait_queue_head_t vsync[NVSYNC];
 
 
 void
 vn_init(void)
 {
-        register sv_t *svp;
-        register int i;
+        int i;
 
-        for (svp = vsync, i = 0; i < NVSYNC; i++, svp++)
-                init_sv(svp, SV_DEFAULT, "vsy", i);
+        for (i = 0; i < NVSYNC; i++)
+                init_waitqueue_head(&vsync[i]);
+}
+
+void
+vn_iowait(
+        struct vnode    *vp)
+{
+        wait_queue_head_t *wq = vptosync(vp);
+
+        wait_event(*wq, (atomic_read(&vp->v_iocount) == 0));
+}
+
+void
+vn_iowake(
+        struct vnode    *vp)
+{
+        if (atomic_dec_and_test(&vp->v_iocount))
+                wake_up(vptosync(vp));
 }
 
 /*
@@ -111,6 +127,8 @@ vn_initialize(
         /* Initialize the first behavior and the behavior chain head. */
         vn_bhv_head_init(VN_BHV_HEAD(vp), "vnode");
 
+        atomic_set(&vp->v_iocount, 0);
+
 #ifdef  XFS_VNODE_TRACE
         vp->v_trace = ktrace_alloc(VNODE_TRACE_SIZE, KM_SLEEP);
 #endif  /* XFS_VNODE_TRACE */