Module Name: src
Committed By: martin
Date: Tue Sep 8 12:02:33 UTC 2015
Modified Files:
src/sys/dev/dkwedge [netbsd-7]: dk.c
Log Message:
Pull up following revision(s) (requested by mlelstv in ticket #967):
sys/dev/dkwedge/dk.c: revision 1.82
No longer access the disk driver directly.
If there is an open wedge, temporarily reference its vnode.
Otherwise try to open the block device.
To generate a diff of this commit:
cvs rdiff -u -r1.72.2.3 -r1.72.2.4 src/sys/dev/dkwedge/dk.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/dkwedge/dk.c
diff -u src/sys/dev/dkwedge/dk.c:1.72.2.3 src/sys/dev/dkwedge/dk.c:1.72.2.4
--- src/sys/dev/dkwedge/dk.c:1.72.2.3 Tue Dec 9 20:17:16 2014
+++ src/sys/dev/dkwedge/dk.c Tue Sep 8 12:02:33 2015
@@ -1,4 +1,4 @@
-/* $NetBSD: dk.c,v 1.72.2.3 2014/12/09 20:17:16 martin Exp $ */
+/* $NetBSD: dk.c,v 1.72.2.4 2015/09/08 12:02:33 martin Exp $ */
/*-
* Copyright (c) 2004, 2005, 2006, 2007 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.72.2.3 2014/12/09 20:17:16 martin Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.72.2.4 2015/09/08 12:02:33 martin Exp $");
#ifdef _KERNEL_OPT
#include "opt_dkwedge.h"
@@ -102,6 +102,8 @@ static int dkwedge_cleanup_parent(struct
static int dkwedge_detach(device_t, int);
static void dkwedge_delall1(struct disk *, bool);
static int dkwedge_del1(struct dkwedge_info *, int);
+static struct vnode *dk_open_parent(dev_t, int);
+static int dk_close_parent(struct vnode *, int);
static dev_type_open(dkopen);
static dev_type_close(dkclose);
@@ -946,34 +948,58 @@ dkwedge_read(struct disk *pdk, struct vn
{
buf_t *bp;
int error;
+ bool isopen;
+ dev_t bdev;
+ struct vnode *bdevvp;
/*
* The kernel cannot read from a character device vnode
* as physio() only handles user memory.
*
- * Determine the corresponding block device and call into
- * the driver directly.
+ * If the block device has already been opened by a wedge
+ * use that vnode and temporarily bump the open counter.
+ *
+ * Otherwise try to open the block device.
*/
- bp = getiobuf(vp, true);
+ bdev = devsw_chr2blk(vp->v_rdev);
+
+ mutex_enter(&pdk->dk_rawlock);
+ if (pdk->dk_rawopens != 0) {
+ KASSERT(pdk->dk_rawvp != NULL);
+ isopen = true;
+ ++pdk->dk_rawopens;
+ bdevvp = pdk->dk_rawvp;
+ } else {
+ isopen = false;
+ bdevvp = dk_open_parent(bdev, FREAD);
+ }
+ mutex_exit(&pdk->dk_rawlock);
+
+ if (bdevvp == NULL)
+ return EBUSY;
+
+ bp = getiobuf(bdevvp, true);
bp->b_flags = B_READ;
bp->b_cflags = BC_BUSY;
- bp->b_dev = devsw_chr2blk(vp->v_rdev);
+ bp->b_dev = bdev;
bp->b_data = tbuf;
bp->b_bufsize = bp->b_bcount = len;
bp->b_blkno = blkno;
bp->b_cylinder = 0;
bp->b_error = 0;
- error = bdev_open(bp->b_dev, FREAD, S_IFBLK, curlwp);
- if (error)
- return error;
-
- bdev_strategy(bp);
+ VOP_STRATEGY(bdevvp, bp);
error = biowait(bp);
putiobuf(bp);
- bdev_close(bp->b_dev, FREAD, S_IFBLK, curlwp);
+ mutex_enter(&pdk->dk_rawlock);
+ if (isopen) {
+ --pdk->dk_rawopens;
+ } else {
+ dk_close_parent(bdevvp, FREAD);
+ }
+ mutex_exit(&pdk->dk_rawlock);
return error;
}
@@ -996,6 +1022,48 @@ dkwedge_lookup(dev_t dev)
return (dkwedges[unit]);
}
+static struct vnode *
+dk_open_parent(dev_t dev, int mode)
+{
+ struct vnode *vp;
+ int error;
+
+ error = bdevvp(dev, &vp);
+ if (error)
+ return NULL;
+
+ error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
+ if (error) {
+ vrele(vp);
+ return NULL;
+ }
+ error = VOP_OPEN(vp, mode, NOCRED);
+ if (error) {
+ vput(vp);
+ return NULL;
+ }
+
+ /* VOP_OPEN() doesn't do this for us. */
+ if (mode & FWRITE) {
+ mutex_enter(vp->v_interlock);
+ vp->v_writecount++;
+ mutex_exit(vp->v_interlock);
+ }
+
+ VOP_UNLOCK(vp);
+
+ return vp;
+}
+
+static int
+dk_close_parent(struct vnode *vp, int mode)
+{
+ int error;
+
+ error = vn_close(vp, mode, NOCRED);
+ return error;
+}
+
/*
* dkopen: [devsw entry point]
*
@@ -1024,24 +1092,9 @@ dkopen(dev_t dev, int flags, int fmt, st
if (sc->sc_dk.dk_openmask == 0) {
if (sc->sc_parent->dk_rawopens == 0) {
KASSERT(sc->sc_parent->dk_rawvp == NULL);
- error = bdevvp(sc->sc_pdev, &vp);
- if (error)
- goto popen_fail;
- error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
- if (error) {
- vrele(vp);
+ vp = dk_open_parent(sc->sc_pdev, FREAD | FWRITE);
+ if (vp == NULL)
goto popen_fail;
- }
- error = VOP_OPEN(vp, FREAD | FWRITE, NOCRED);
- if (error) {
- vput(vp);
- goto popen_fail;
- }
- /* VOP_OPEN() doesn't do this for us. */
- mutex_enter(vp->v_interlock);
- vp->v_writecount++;
- mutex_exit(vp->v_interlock);
- VOP_UNLOCK(vp);
sc->sc_parent->dk_rawvp = vp;
}
sc->sc_parent->dk_rawopens++;
@@ -1077,8 +1130,7 @@ dklastclose(struct dkwedge_softc *sc)
if (doclose) {
KASSERT(sc->sc_parent->dk_rawvp != NULL);
- error = vn_close(sc->sc_parent->dk_rawvp,
- FREAD | FWRITE, NOCRED);
+ dk_close_parent(sc->sc_parent->dk_rawvp, FREAD | FWRITE);
sc->sc_parent->dk_rawvp = NULL;
}
