Tue Apr 14 08:22:00 2020 UTC ()
if grant fails also revoke the grants for previous segments, fixes
grant leak on grant error


(jdolecek)
diff -r1.107 -r1.108 src/sys/arch/xen/xen/xbd_xenbus.c
cvs diff -r1.107 -r1.108 src/sys/arch/xen/xen/xbd_xenbus.c (expand / switch to unified diff)

--- src/sys/arch/xen/xen/xbd_xenbus.c 2020/04/13 20:09:13 1.107
+++ src/sys/arch/xen/xen/xbd_xenbus.c 2020/04/14 08:21:59 1.108
@@ -1,14 +1,14 @@ @@ -1,14 +1,14 @@
1/* $NetBSD: xbd_xenbus.c,v 1.107 2020/04/13 20:09:13 jdolecek Exp $ */ 1/* $NetBSD: xbd_xenbus.c,v 1.108 2020/04/14 08:21:59 jdolecek Exp $ */
2 2
3/* 3/*
4 * Copyright (c) 2006 Manuel Bouyer. 4 * Copyright (c) 2006 Manuel Bouyer.
5 * 5 *
6 * Redistribution and use in source and binary forms, with or without 6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions 7 * modification, are permitted provided that the following conditions
8 * are met: 8 * are met:
9 * 1. Redistributions of source code must retain the above copyright 9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer. 10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright 11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the 12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution. 13 * documentation and/or other materials provided with the distribution.
14 * 14 *
@@ -40,27 +40,27 @@ @@ -40,27 +40,27 @@
40 * - initiate request: xbdread/write/open/ioctl/.. 40 * - initiate request: xbdread/write/open/ioctl/..
41 * - depending on operation, it is handled directly by disk(9) subsystem or 41 * - depending on operation, it is handled directly by disk(9) subsystem or
42 * goes through physio(9) first. 42 * goes through physio(9) first.
43 * - the request is ultimately processed by xbd_diskstart() that prepares the 43 * - the request is ultimately processed by xbd_diskstart() that prepares the
44 * xbd requests, post them in the ring I/O queue, then signal the backend. 44 * xbd requests, post them in the ring I/O queue, then signal the backend.
45 * 45 *
46 * When a response is available in the queue, the backend signals the frontend 46 * When a response is available in the queue, the backend signals the frontend
47 * via its event channel. This triggers xbd_handler(), which will link back 47 * via its event channel. This triggers xbd_handler(), which will link back
48 * the response to its request through the request ID, and mark the I/O as 48 * the response to its request through the request ID, and mark the I/O as
49 * completed. 49 * completed.
50 */ 50 */
51 51
52#include <sys/cdefs.h> 52#include <sys/cdefs.h>
53__KERNEL_RCSID(0, "$NetBSD: xbd_xenbus.c,v 1.107 2020/04/13 20:09:13 jdolecek Exp $"); 53__KERNEL_RCSID(0, "$NetBSD: xbd_xenbus.c,v 1.108 2020/04/14 08:21:59 jdolecek Exp $");
54 54
55#include "opt_xen.h" 55#include "opt_xen.h"
56 56
57 57
58#include <sys/param.h> 58#include <sys/param.h>
59#include <sys/buf.h> 59#include <sys/buf.h>
60#include <sys/bufq.h> 60#include <sys/bufq.h>
61#include <sys/device.h> 61#include <sys/device.h>
62#include <sys/disk.h> 62#include <sys/disk.h>
63#include <sys/disklabel.h> 63#include <sys/disklabel.h>
64#include <sys/conf.h> 64#include <sys/conf.h>
65#include <sys/fcntl.h> 65#include <sys/fcntl.h>
66#include <sys/kernel.h> 66#include <sys/kernel.h>
@@ -1039,26 +1039,32 @@ xbd_diskstart(device_t self, struct buf  @@ -1039,26 +1039,32 @@ xbd_diskstart(device_t self, struct buf
1039 nsects = nbytes >> XEN_BSHIFT; 1039 nsects = nbytes >> XEN_BSHIFT;
1040 1040
1041 req->seg[seg].first_sect = off >> XEN_BSHIFT; 1041 req->seg[seg].first_sect = off >> XEN_BSHIFT;
1042 req->seg[seg].last_sect = (off >> XEN_BSHIFT) + nsects - 1; 1042 req->seg[seg].last_sect = (off >> XEN_BSHIFT) + nsects - 1;
1043 KASSERT(req->seg[seg].first_sect <= req->seg[seg].last_sect); 1043 KASSERT(req->seg[seg].first_sect <= req->seg[seg].last_sect);
1044 KASSERT(req->seg[seg].last_sect < (PAGE_SIZE / XEN_BSIZE)); 1044 KASSERT(req->seg[seg].last_sect < (PAGE_SIZE / XEN_BSIZE));
1045 1045
1046 if (__predict_false(xengnt_grant_access( 1046 if (__predict_false(xengnt_grant_access(
1047 sc->sc_xbusd->xbusd_otherend_id, 1047 sc->sc_xbusd->xbusd_otherend_id,
1048 (ma & ~PAGE_MASK), (bp->b_flags & B_READ) == 0, 1048 (ma & ~PAGE_MASK), (bp->b_flags & B_READ) == 0,
1049 &xbdreq->req_gntref[seg]))) { 1049 &xbdreq->req_gntref[seg]))) {
1050 printf("%s: %s: xengnt_grant_access failed", 1050 printf("%s: %s: xengnt_grant_access failed",
1051 device_xname(sc->sc_dksc.sc_dev), __func__); 1051 device_xname(sc->sc_dksc.sc_dev), __func__);
 1052 if (seg > 0) {
 1053 for (; --seg >= 0; ) {
 1054 xengnt_revoke_access(
 1055 xbdreq->req_gntref[seg]);
 1056 }
 1057 }
1052 bus_dmamap_unload(sc->sc_xbusd->xbusd_dmat, 1058 bus_dmamap_unload(sc->sc_xbusd->xbusd_dmat,
1053 xbdreq->req_dmamap); 1059 xbdreq->req_dmamap);
1054 SLIST_INSERT_HEAD(&sc->sc_xbdreq_head, xbdreq, 1060 SLIST_INSERT_HEAD(&sc->sc_xbdreq_head, xbdreq,
1055 req_next); 1061 req_next);
1056 error = EFAULT; 1062 error = EFAULT;
1057 goto out; 1063 goto out;
1058 } 1064 }
1059 1065
1060 req->seg[seg].gref = xbdreq->req_gntref[seg]; 1066 req->seg[seg].gref = xbdreq->req_gntref[seg];
1061 } 1067 }
1062 req->nr_segments = seg; 1068 req->nr_segments = seg;
1063 sc->sc_ring.req_prod_pvt++; 1069 sc->sc_ring.req_prod_pvt++;
1064 1070