[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>

diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index bd9aba1f23538a3c2af01ceaac28def63d8db6f6..b55cb7f02e886e5f23cd7d7ef7e5467e2ce63478 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -139,7 +139,7 @@ linvfs_unwritten_convert(
        XFS_BUF_SET_FSPRIVATE(bp, NULL);
        XFS_BUF_CLR_IODONE_FUNC(bp);
        XFS_BUF_UNDATAIO(bp);
-       iput(LINVFS_GET_IP(vp));
+       vn_iowake(vp);
        pagebuf_iodone(bp, 0, 0);
 }
 
@@ -448,14 +448,7 @@ xfs_map_unwritten(
        if (!pb)
                return -EAGAIN;
 
-       /* Take a reference to the inode to prevent it from
-        * being reclaimed while we have outstanding unwritten
-        * extent IO on it.
-        */
-       if ((igrab(inode)) != inode) {
-               pagebuf_free(pb);
-               return -EAGAIN;
-       }
+       atomic_inc(&LINVFS_GET_VP(inode)->v_iocount);
 
        /* Set the count to 1 initially, this will stop an I/O
         * completion callout which happens before we have started

diff --git a/fs/xfs/linux-2.6/xfs_vnode.c b/fs/xfs/linux-2.6/xfs_vnode.c
index 654da98de2a5c20d905b0473f27d7b3e84b5bf7d..46afc86a286210b58f4b57c405a0f0cce17fdd60 100644 (file)
--- 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 */

diff --git a/fs/xfs/linux-2.6/xfs_vnode.h b/fs/xfs/linux-2.6/xfs_vnode.h
index 4a74569a569099943a5f84ddbdf5f0fe90a77710..9977afa38900e08ed712a25466c483b5940626d9 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_vnode.h
+++ b/fs/xfs/linux-2.6/xfs_vnode.h
@@ -80,6 +80,7 @@ typedef struct vnode {
        vnumber_t       v_number;               /* in-core vnode number */
        vn_bhv_head_t   v_bh;                   /* behavior head */
        spinlock_t      v_lock;                 /* VN_LOCK/VN_UNLOCK */
+       atomic_t        v_iocount;              /* outstanding I/O count */
 #ifdef XFS_VNODE_TRACE
        struct ktrace   *v_trace;               /* trace header structure    */
 #endif
@@ -506,6 +507,9 @@ extern int  vn_revalidate(struct vnode *);
 extern void    vn_revalidate_core(struct vnode *, vattr_t *);
 extern void    vn_remove(struct vnode *);
 
+extern void    vn_iowait(struct vnode *vp);
+extern void    vn_iowake(struct vnode *vp);
+
 static inline int vn_count(struct vnode *vp)
 {
        return atomic_read(&LINVFS_GET_IP(vp)->i_count);

diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index c4aa24ff85a2610e6f402cb5b64402a5a418bf27..58bfe629b93316168b5c2ded720b6ea9cf0b6a7a 100644 (file)
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -3846,51 +3846,10 @@ xfs_reclaim(
                return 0;
        }
 
-       if ((ip->i_d.di_mode & S_IFMT) == S_IFREG) {
-               if (ip->i_d.di_size > 0) {
-                       /*
-                        * Flush and invalidate any data left around that is
-                        * a part of this file.
-                        *
-                        * Get the inode's i/o lock so that buffers are pushed
-                        * out while holding the proper lock.  We can't hold
-                        * the inode lock here since flushing out buffers may
-                        * cause us to try to get the lock in xfs_strategy().
-                        *
-                        * We don't have to call remapf() here, because there
-                        * cannot be any mapped file references to this vnode
-                        * since it is being reclaimed.
-                        */
-                       xfs_ilock(ip, XFS_IOLOCK_EXCL);
-
-                       /*
-                        * If we hit an IO error, we need to make sure that the
-                        * buffer and page caches of file data for
-                        * the file are tossed away. We don't want to use
-                        * VOP_FLUSHINVAL_PAGES here because we don't want dirty
-                        * pages to stay attached to the vnode, but be
-                        * marked P_BAD. pdflush/vnode_pagebad
-                        * hates that.
-                        */
-                       if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
-                               VOP_FLUSHINVAL_PAGES(vp, 0, -1, FI_NONE);
-                       } else {
-                               VOP_TOSS_PAGES(vp, 0, -1, FI_NONE);
-                       }
+       vn_iowait(vp);
 
-                       ASSERT(VN_CACHED(vp) == 0);
-                       ASSERT(XFS_FORCED_SHUTDOWN(ip->i_mount) ||
-                              ip->i_delayed_blks == 0);
-                       xfs_iunlock(ip, XFS_IOLOCK_EXCL);
-               } else if (XFS_FORCED_SHUTDOWN(ip->i_mount)) {
-                       /*
-                        * di_size field may not be quite accurate if we're
-                        * shutting down.
-                        */
-                       VOP_TOSS_PAGES(vp, 0, -1, FI_NONE);
-                       ASSERT(VN_CACHED(vp) == 0);
-               }
-       }
+       ASSERT(XFS_FORCED_SHUTDOWN(ip->i_mount) || ip->i_delayed_blks == 0);
+       ASSERT(VN_CACHED(vp) == 0);
 
        /* If we have nothing to flush with this inode then complete the
         * teardown now, otherwise break the link between the xfs inode