[src/trunk]: src/sys/uvm don't mess with vnode holds or buffer lists for swap...

[chs <chs%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/423d71a977da
branches:  trunk
changeset: 514214:423d71a977da
user:      chs <chs%NetBSD.org@localhost>
date:      Sun Aug 26 00:43:53 2001 +0000

description:
don't mess with vnode holds or buffer lists for swap i/os.
fixes problems with leaked vnode holds.

diffstat:

 sys/uvm/uvm_swap.c |  33 ++++++---------------------------
 1 files changed, 6 insertions(+), 27 deletions(-)

diffs (90 lines):

diff -r 1ac338c23eb9 -r 423d71a977da sys/uvm/uvm_swap.c
--- a/sys/uvm/uvm_swap.c        Sun Aug 26 00:02:46 2001 +0000
+++ b/sys/uvm/uvm_swap.c        Sun Aug 26 00:43:53 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uvm_swap.c,v 1.52 2001/05/26 16:32:47 chs Exp $        */
+/*     $NetBSD: uvm_swap.c,v 1.53 2001/08/26 00:43:53 chs Exp $        */
 
 /*
  * Copyright (c) 1995, 1996, 1997 Matthew R. Green
@@ -1118,7 +1118,6 @@
                bp->b_blkno = bn;               /* swapdev block number */
                vp = sdp->swd_vp;               /* swapdev vnode pointer */
                bp->b_dev = sdp->swd_dev;       /* swapdev dev_t */
-               VHOLD(vp);                      /* "hold" swapdev vp for i/o */
 
                /*
                 * if we are doing a write, we have to redirect the i/o on
@@ -1130,13 +1129,6 @@
                }
 
                /*
-                * dissassocate buffer with /dev/drum vnode
-                * [could be null if buf was from physio]
-                */
-               if (bp->b_vp != NULL)
-                       brelvp(bp);
-
-               /*
                 * finally plug in swapdev vnode and start I/O
                 */
                bp->b_vp = vp;
@@ -1260,7 +1252,10 @@
                nbp->vb_buf.b_blkno    = nbn + btodb(off);
                nbp->vb_buf.b_rawblkno = nbp->vb_buf.b_blkno;
                nbp->vb_buf.b_iodone   = sw_reg_iodone;
-               nbp->vb_buf.b_vp       = NULL;
+               nbp->vb_buf.b_vp       = vp;
+               if (vp->v_type == VBLK) {
+                       nbp->vb_buf.b_dev = vp->v_rdev;
+               }
                LIST_INIT(&nbp->vb_buf.b_dep);
 
                nbp->vb_xfer = vnx;     /* patch it back in to vnx */
@@ -1275,9 +1270,6 @@
                }
                vnx->vx_pending++;
 
-               /* assoc new buffer with underlying vnode */
-               bgetvp(vp, &nbp->vb_buf);
-
                /* sort it in and start I/O if we are not over our limit */
                disksort_blkno(&sdp->swd_tab, &nbp->vb_buf);
                sw_reg_start(sdp);
@@ -1380,11 +1372,6 @@
        }
 
        /*
-        * disassociate this buffer from the vnode.
-        */
-       brelvp(&vbp->vb_buf);
-
-       /*
         * kill vbp structure
         */
        putvndbuf(vbp);
@@ -1697,14 +1684,8 @@
        bp->b_vnbufs.le_next = NOLIST;
        bp->b_data = (caddr_t)kva;
        bp->b_blkno = startblk;
-       s = splbio();
-       VHOLD(swapdev_vp);
        bp->b_vp = swapdev_vp;
-       splx(s);
-       /* XXXCDC: isn't swapdev_vp always a VCHR? */
-       /* XXXMRG: probably -- this is obviously something inherited... */
-       if (swapdev_vp->v_type == VBLK)
-               bp->b_dev = swapdev_vp->v_rdev;
+       bp->b_dev = swapdev_vp->v_rdev;
        bp->b_bufsize = bp->b_bcount = npages << PAGE_SHIFT;
        LIST_INIT(&bp->b_dep);
 
@@ -1752,8 +1733,6 @@
         * now dispose of the buf
         */
        s = splbio();
-       if (bp->b_vp)
-               brelvp(bp);
        if (write)
                vwakeup(bp);
        pool_put(&bufpool, bp);