[XFS] XFS should not be looking at filp reference counts

A check for file_count is always a bad idea. Linux has the ->release
method to deal with cleanups on last close and ->flush is only for the
very rare case where we want to perform an operation on every drop of a
reference to a file struct.

This patch gets rid of vop_close and surrounding code in favour of simply
doing the page flushing from ->release.

SGI-PV: 966562
SGI-Modid: xfs-linux-melb:xfs-kern:28952a

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>

3 files changed, 16 insertions, 47 deletions

diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c
index 8c43cd2e237a..cbcd40c8c2a0 100644
--- a/fs/xfs/linux-2.6/xfs_file.c
+++ b/fs/xfs/linux-2.6/xfs_file.c
@@ -184,15 +184,6 @@ xfs_file_open(
 }
 
 STATIC int
-xfs_file_close(
-        struct file     *filp,
-        fl_owner_t      id)
-{
-        return -bhv_vop_close(vn_from_inode(filp->f_path.dentry->d_inode), 0,
-                                file_count(filp) > 1 ? L_FALSE : L_TRUE, NULL);
-}
-
-STATIC int
 xfs_file_release(
         struct inode    *inode,
         struct file     *filp)
@@ -436,7 +427,6 @@ const struct file_operations xfs_file_operations = {
 #endif
         .mmap           = xfs_file_mmap,
         .open           = xfs_file_open,
-        .flush          = xfs_file_close,
         .release        = xfs_file_release,
         .fsync          = xfs_file_fsync,
 #ifdef HAVE_FOP_OPEN_EXEC
@@ -458,7 +448,6 @@ const struct file_operations xfs_invis_file_operations = {
 #endif
         .mmap           = xfs_file_mmap,
         .open           = xfs_file_open,
-        .flush          = xfs_file_close,
         .release        = xfs_file_release,
         .fsync          = xfs_file_fsync,
 };
diff --git a/fs/xfs/linux-2.6/xfs_vnode.h b/fs/xfs/linux-2.6/xfs_vnode.h
index 013048a92643..5742d65f0785 100644
--- a/fs/xfs/linux-2.6/xfs_vnode.h
+++ b/fs/xfs/linux-2.6/xfs_vnode.h
@@ -129,10 +129,7 @@ typedef enum bhv_vchange {
         VCHANGE_FLAGS_IOEXCL_COUNT      = 4
 } bhv_vchange_t;
 
-typedef enum { L_FALSE, L_TRUE } lastclose_t;
-
 typedef int     (*vop_open_t)(bhv_desc_t *, struct cred *);
-typedef int     (*vop_close_t)(bhv_desc_t *, int, lastclose_t, struct cred *);
 typedef ssize_t (*vop_read_t)(bhv_desc_t *, struct kiocb *,
                                 const struct iovec *, unsigned int,
                                 loff_t *, int, struct cred *);
@@ -200,7 +197,6 @@ typedef int	(*vop_iflush_t)(bhv_desc_t *, int);
 typedef struct bhv_vnodeops {
         bhv_position_t  vn_position;    /* position within behavior chain */
         vop_open_t              vop_open;
-        vop_close_t             vop_close;
         vop_read_t              vop_read;
         vop_write_t             vop_write;
         vop_splice_read_t       vop_splice_read;
@@ -245,7 +241,6 @@ typedef struct bhv_vnodeops {
 #define VNHEAD(vp)      ((vp)->v_bh.bh_first)
 #define VOP(op, vp)     (*((bhv_vnodeops_t *)VNHEAD(vp)->bd_ops)->op)
 #define bhv_vop_open(vp, cr)            VOP(vop_open, vp)(VNHEAD(vp),cr)
-#define bhv_vop_close(vp, f,last,cr)    VOP(vop_close, vp)(VNHEAD(vp),f,last,cr)
 #define bhv_vop_read(vp,file,iov,segs,offset,ioflags,cr)                \
                 VOP(vop_read, vp)(VNHEAD(vp),file,iov,segs,offset,ioflags,cr)
 #define bhv_vop_write(vp,file,iov,segs,offset,ioflags,cr)               \
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index 5dbca95598e0..2067d0b0a10e 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -77,36 +77,6 @@ xfs_open(
         return 0;
 }
 
-STATIC int
-xfs_close(
-        bhv_desc_t      *bdp,
-        int             flags,
-        lastclose_t     lastclose,
-        cred_t          *credp)
-{
-        bhv_vnode_t     *vp = BHV_TO_VNODE(bdp);
-        xfs_inode_t     *ip = XFS_BHVTOI(bdp);
-
-        if (XFS_FORCED_SHUTDOWN(ip->i_mount))
-                return XFS_ERROR(EIO);
-
-        if (lastclose != L_TRUE || !VN_ISREG(vp))
-                return 0;
-
-        /*
-         * If we previously truncated this file and removed old data in
-         * the process, we want to initiate "early" writeout on the last
-         * close.  This is an attempt to combat the notorious NULL files
-         * problem which is particularly noticable from a truncate down,
-         * buffered (re-)write (delalloc), followed by a crash.  What we
-         * are effectively doing here is significantly reducing the time
-         * window where we'd otherwise be exposed to that problem.
-         */
-        if (VUNTRUNCATE(vp) && VN_DIRTY(vp) && ip->i_delayed_blks > 0)
-                return bhv_vop_flush_pages(vp, 0, -1, XFS_B_ASYNC, FI_NONE);
-        return 0;
-}
-
 /*
  * xfs_getattr
  */
@@ -1566,6 +1536,22 @@ xfs_release(
         if (vp->v_vfsp->vfs_flag & VFS_RDONLY)
                 return 0;
 
+        if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
+                /*
+                 * If we previously truncated this file and removed old data
+                 * in the process, we want to initiate "early" writeout on
+                 * the last close.  This is an attempt to combat the notorious
+                 * NULL files problem which is particularly noticable from a
+                 * truncate down, buffered (re-)write (delalloc), followed by
+                 * a crash.  What we are effectively doing here is
+                 * significantly reducing the time window where we'd otherwise
+                 * be exposed to that problem.
+                 */
+                if (VUNTRUNCATE(vp) && VN_DIRTY(vp) && ip->i_delayed_blks > 0)
+                        bhv_vop_flush_pages(vp, 0, -1, XFS_B_ASYNC, FI_NONE);
+        }
+
+
 #ifdef HAVE_REFCACHE
         /* If we are in the NFS reference cache then don't do this now */
         if (ip->i_refcache)
@@ -4681,7 +4667,6 @@ xfs_change_file_space(
 bhv_vnodeops_t xfs_vnodeops = {
         BHV_IDENTITY_INIT(VN_BHV_XFS,VNODE_POSITION_XFS),
         .vop_open               = xfs_open,
-        .vop_close              = xfs_close,
         .vop_read               = xfs_read,
 #ifdef HAVE_SPLICE
         .vop_splice_read        = xfs_splice_read,