| Message ID | 1515516013-16604-1-git-send-email-jianjay.zhou@huawei.com |
|---|---|
| State | New |
| Headers | show |
| Series | vhost: two fixes and used_memslots refactoring | expand |
Sorry about missing to cc Jason.
Close the fd of the tap unconditionally when netdev_add tap,id=net0,vhost=on failed
in net_init_tap_one() will make the followed up device_add virtio-net-pci,netdev=net0
failed too, which prints:
TUNSETOFFLOAD ioctl() failed: Bad file descriptor TUNSETOFFLOAD
ioctl() failed: Bad file descriptor
This patch makes the followed up device_add be able to fall back to userspace virtio
when netdev_add failed with vhost turning on but vhost force flag does not set.
Here is the original discussion:
https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg05205.html
This is a RFC version, if I'm wrong, please let me know, thanks!
PS: there're two places updated, see below.
> -----Original Message-----
> From: Zhoujian (jay)
> Sent: Wednesday, January 10, 2018 12:40 AM
> To: qemu-devel@nongnu.org
> Cc: mst@redhat.com; imammedo@redhat.com; Huangweidong (C)
> <weidong.huang@huawei.com>; wangxin (U) <wangxinxin.wang@huawei.com>; Gonglei
> (Arei) <arei.gonglei@huawei.com>; Liuzhe (Ahriy, Euler) <liuzhe13@huawei.com>;
> Zhoujian (jay) <jianjay.zhou@huawei.com>
> Subject: [PATCH v5 2/4][RFC] tap: do not close fd if only vhost failed to
> initialize
>
> Making the followed up device_add to fall back to userspace virtio when
> netdev_add fails if vhost force flag does not set.
>
> Suggested-by: Michael S. Tsirkin <mst@redhat.com>
> Suggested-by: Igor Mammedov <imammedo@redhat.com>
> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
> ---
> net/tap.c | 25 ++++++++++++++++++-------
> 1 file changed, 18 insertions(+), 7 deletions(-)
>
> diff --git a/net/tap.c b/net/tap.c
> index 979e622..03f226f 100644
> --- a/net/tap.c
> +++ b/net/tap.c
> @@ -642,7 +642,8 @@ static void net_init_tap_one(const NetdevTapOptions *tap,
> NetClientState *peer,
> const char *model, const char *name,
> const char *ifname, const char *script,
> const char *downscript, const char *vhostfdname,
> - int vnet_hdr, int fd, Error **errp)
> + int vnet_hdr, int fd, Error **errp,
> + bool *vhost_init_failed)
> {
> Error *err = NULL;
> TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); @@ -
> 687,6 +688,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap,
> NetClientState *peer,
> vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err);
> if (vhostfd == -1) {
> error_propagate(errp, err);
> + *vhost_init_failed = true;
> return;
> }
> } else {
> @@ -694,6 +696,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap,
> NetClientState *peer,
> if (vhostfd < 0) {
> error_setg_errno(errp, errno,
> "tap: open vhost char device failed");
> + *vhost_init_failed = true;
> return;
> }
> fcntl(vhostfd, F_SETFL, O_NONBLOCK); @@ -704,6 +707,7 @@ static
> void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
> if (!s->vhost_net) {
> error_setg(errp,
> "vhost-net requested but could not be initialized");
> + *vhost_init_failed = true;
> return;
> }
> } else if (vhostfdname) {
> @@ -748,6 +752,7 @@ int net_init_tap(const Netdev *netdev, const char *name,
> Error *err = NULL;
> const char *vhostfdname;
> char ifname[128];
> + bool vhost_init_failed = false;
>
> assert(netdev->type == NET_CLIENT_DRIVER_TAP);
> tap = &netdev->u.tap;
> @@ -783,7 +788,7 @@ int net_init_tap(const Netdev *netdev, const char *name,
>
> net_init_tap_one(tap, peer, "tap", name, NULL,
> script, downscript,
> - vhostfdname, vnet_hdr, fd, &err);
> + vhostfdname, vnet_hdr, fd, &err,
> + &vhost_init_failed);
> if (err) {
> error_propagate(errp, err);
> return -1;
> @@ -835,7 +840,7 @@ int net_init_tap(const Netdev *netdev, const char *name,
> net_init_tap_one(tap, peer, "tap", name, ifname,
> script, downscript,
> tap->has_vhostfds ? vhost_fds[i] : NULL,
> - vnet_hdr, fd, &err);
> + vnet_hdr, fd, &err, &vhost_init_failed);
> if (err) {
> error_propagate(errp, err);
> goto free_fail;
> @@ -874,10 +879,12 @@ free_fail:
>
> net_init_tap_one(tap, peer, "bridge", name, ifname,
> script, downscript, vhostfdname,
> - vnet_hdr, fd, &err);
> + vnet_hdr, fd, &err, &vhost_init_failed);
> if (err) {
> error_propagate(errp, err);
> - close(fd);
> + if (tap->has_vhostforce && tap->vhostforce && vhost_init_failed)
> {
> + close(fd);
> + }
This should be:
if (!vhost_init_failed || (tap->has_vhostforce && tap->vhostforce)) {
close(fd);
}
> return -1;
> }
> } else {
> @@ -913,10 +920,14 @@ free_fail:
> net_init_tap_one(tap, peer, "tap", name, ifname,
> i >= 1 ? "no" : script,
> i >= 1 ? "no" : downscript,
> - vhostfdname, vnet_hdr, fd, &err);
> + vhostfdname, vnet_hdr, fd, &err,
> + &vhost_init_failed);
> if (err) {
> error_propagate(errp, err);
> - close(fd);
> + if (tap->has_vhostforce && tap->vhostforce &&
> + vhost_init_failed) {
> + close(fd);
> + }
Same here, this should be:
if (!vhost_init_failed || (tap->has_vhostforce && tap->vhostforce)) {
close(fd);
}
> return -1;
> }
> }
> --
> 1.8.3.1
>
On 2018年01月10日 12:18, Zhoujian (jay) wrote: > Sorry about missing to cc Jason. > > > Close the fd of the tap unconditionally when netdev_add tap,id=net0,vhost=on failed > in net_init_tap_one() will make the followed up device_add virtio-net-pci,netdev=net0 > failed too, which prints: > > TUNSETOFFLOAD ioctl() failed: Bad file descriptor TUNSETOFFLOAD > ioctl() failed: Bad file descriptor > > This patch makes the followed up device_add be able to fall back to userspace virtio > when netdev_add failed with vhost turning on but vhost force flag does not set. > > Here is the original discussion: > https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg05205.html > > > This is a RFC version, if I'm wrong, please let me know, thanks! > > PS: there're two places updated, see below. > > >> -----Original Message----- >> From: Zhoujian (jay) >> Sent: Wednesday, January 10, 2018 12:40 AM >> To: qemu-devel@nongnu.org >> Cc: mst@redhat.com; imammedo@redhat.com; Huangweidong (C) >> <weidong.huang@huawei.com>; wangxin (U) <wangxinxin.wang@huawei.com>; Gonglei >> (Arei) <arei.gonglei@huawei.com>; Liuzhe (Ahriy, Euler) <liuzhe13@huawei.com>; >> Zhoujian (jay) <jianjay.zhou@huawei.com> >> Subject: [PATCH v5 2/4][RFC] tap: do not close fd if only vhost failed to >> initialize >> >> Making the followed up device_add to fall back to userspace virtio when >> netdev_add fails if vhost force flag does not set. >> >> Suggested-by: Michael S. Tsirkin <mst@redhat.com> >> Suggested-by: Igor Mammedov <imammedo@redhat.com> >> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com> >> --- >> net/tap.c | 25 ++++++++++++++++++------- >> 1 file changed, 18 insertions(+), 7 deletions(-) >> >> diff --git a/net/tap.c b/net/tap.c >> index 979e622..03f226f 100644 >> --- a/net/tap.c >> +++ b/net/tap.c >> @@ -642,7 +642,8 @@ static void net_init_tap_one(const NetdevTapOptions *tap, >> NetClientState *peer, >> const char *model, const char *name, >> const char *ifname, const char *script, >> const char *downscript, const char *vhostfdname, >> - int vnet_hdr, int fd, Error **errp) >> + int vnet_hdr, int fd, Error **errp, >> + bool *vhost_init_failed) >> { >> Error *err = NULL; >> TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); @@ - >> 687,6 +688,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, >> NetClientState *peer, >> vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err); >> if (vhostfd == -1) { >> error_propagate(errp, err); >> + *vhost_init_failed = true; >> return; >> } >> } else { >> @@ -694,6 +696,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, >> NetClientState *peer, >> if (vhostfd < 0) { >> error_setg_errno(errp, errno, >> "tap: open vhost char device failed"); >> + *vhost_init_failed = true; >> return; >> } >> fcntl(vhostfd, F_SETFL, O_NONBLOCK); @@ -704,6 +707,7 @@ static >> void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, >> if (!s->vhost_net) { >> error_setg(errp, >> "vhost-net requested but could not be initialized"); >> + *vhost_init_failed = true; Why not simply check s->vhost_net after call net_init_tap_one()? Thanks >> return; >> } >> } else if (vhostfdname) { >> @@ -748,6 +752,7 @@ int net_init_tap(const Netdev *netdev, const char *name, >> Error *err = NULL; >> const char *vhostfdname; >> char ifname[128]; >> + bool vhost_init_failed = false; >> >> assert(netdev->type == NET_CLIENT_DRIVER_TAP); >> tap = &netdev->u.tap; >> @@ -783,7 +788,7 @@ int net_init_tap(const Netdev *netdev, const char *name, >> >> net_init_tap_one(tap, peer, "tap", name, NULL, >> script, downscript, >> - vhostfdname, vnet_hdr, fd, &err); >> + vhostfdname, vnet_hdr, fd, &err, >> + &vhost_init_failed); >> if (err) { >> error_propagate(errp, err); >> return -1; >> @@ -835,7 +840,7 @@ int net_init_tap(const Netdev *netdev, const char *name, >> net_init_tap_one(tap, peer, "tap", name, ifname, >> script, downscript, >> tap->has_vhostfds ? vhost_fds[i] : NULL, >> - vnet_hdr, fd, &err); >> + vnet_hdr, fd, &err, &vhost_init_failed); >> if (err) { >> error_propagate(errp, err); >> goto free_fail; >> @@ -874,10 +879,12 @@ free_fail: >> >> net_init_tap_one(tap, peer, "bridge", name, ifname, >> script, downscript, vhostfdname, >> - vnet_hdr, fd, &err); >> + vnet_hdr, fd, &err, &vhost_init_failed); >> if (err) { >> error_propagate(errp, err); >> - close(fd); >> + if (tap->has_vhostforce && tap->vhostforce && vhost_init_failed) >> { >> + close(fd); >> + } > This should be: > > if (!vhost_init_failed || (tap->has_vhostforce && tap->vhostforce)) { > close(fd); > } > >> return -1; >> } >> } else { >> @@ -913,10 +920,14 @@ free_fail: >> net_init_tap_one(tap, peer, "tap", name, ifname, >> i >= 1 ? "no" : script, >> i >= 1 ? "no" : downscript, >> - vhostfdname, vnet_hdr, fd, &err); >> + vhostfdname, vnet_hdr, fd, &err, >> + &vhost_init_failed); >> if (err) { >> error_propagate(errp, err); >> - close(fd); >> + if (tap->has_vhostforce && tap->vhostforce && >> + vhost_init_failed) { >> + close(fd); >> + } > Same here, this should be: > > if (!vhost_init_failed || (tap->has_vhostforce && tap->vhostforce)) { > close(fd); > } > >> return -1; >> } >> } >> -- >> 1.8.3.1 >> >
> -----Original Message----- > From: Jason Wang [mailto:jasowang@redhat.com] > Sent: Wednesday, January 10, 2018 2:02 PM > To: Zhoujian (jay) <jianjay.zhou@huawei.com>; qemu-devel@nongnu.org > Cc: Huangweidong (C) <weidong.huang@huawei.com>; mst@redhat.com; wangxin (U) > <wangxinxin.wang@huawei.com>; Gonglei (Arei) <arei.gonglei@huawei.com>; > imammedo@redhat.com; Liuzhe (Ahriy, Euler) <liuzhe13@huawei.com> > Subject: Re: [Qemu-devel] [PATCH v5 2/4][RFC] tap: do not close fd if only > vhost failed to initialize > > > > On 2018年01月10日 12:18, Zhoujian (jay) wrote: > > Sorry about missing to cc Jason. > > > > > > Close the fd of the tap unconditionally when netdev_add > > tap,id=net0,vhost=on failed in net_init_tap_one() will make the > > followed up device_add virtio-net-pci,netdev=net0 failed too, which prints: > > > > TUNSETOFFLOAD ioctl() failed: Bad file descriptor TUNSETOFFLOAD > > ioctl() failed: Bad file descriptor > > > > This patch makes the followed up device_add be able to fall back to > > userspace virtio when netdev_add failed with vhost turning on but vhost > force flag does not set. > > > > Here is the original discussion: > > https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg05205.html > > > > > > This is a RFC version, if I'm wrong, please let me know, thanks! > > > > PS: there're two places updated, see below. > > > > > >> -----Original Message----- > >> From: Zhoujian (jay) > >> Sent: Wednesday, January 10, 2018 12:40 AM > >> To: qemu-devel@nongnu.org > >> Cc: mst@redhat.com; imammedo@redhat.com; Huangweidong (C) > >> <weidong.huang@huawei.com>; wangxin (U) <wangxinxin.wang@huawei.com>; > >> Gonglei > >> (Arei) <arei.gonglei@huawei.com>; Liuzhe (Ahriy, Euler) > >> <liuzhe13@huawei.com>; Zhoujian (jay) <jianjay.zhou@huawei.com> > >> Subject: [PATCH v5 2/4][RFC] tap: do not close fd if only vhost > >> failed to initialize > >> > >> Making the followed up device_add to fall back to userspace virtio > >> when netdev_add fails if vhost force flag does not set. > >> > >> Suggested-by: Michael S. Tsirkin <mst@redhat.com> > >> Suggested-by: Igor Mammedov <imammedo@redhat.com> > >> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com> > >> --- > >> net/tap.c | 25 ++++++++++++++++++------- > >> 1 file changed, 18 insertions(+), 7 deletions(-) > >> > >> diff --git a/net/tap.c b/net/tap.c > >> index 979e622..03f226f 100644 > >> --- a/net/tap.c > >> +++ b/net/tap.c > >> @@ -642,7 +642,8 @@ static void net_init_tap_one(const > >> NetdevTapOptions *tap, NetClientState *peer, > >> const char *model, const char *name, > >> const char *ifname, const char *script, > >> const char *downscript, const char > *vhostfdname, > >> - int vnet_hdr, int fd, Error **errp) > >> + int vnet_hdr, int fd, Error **errp, > >> + bool *vhost_init_failed) > >> { > >> Error *err = NULL; > >> TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); > >> @@ - > >> 687,6 +688,7 @@ static void net_init_tap_one(const NetdevTapOptions > >> *tap, NetClientState *peer, > >> vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err); > >> if (vhostfd == -1) { > >> error_propagate(errp, err); > >> + *vhost_init_failed = true; > >> return; > >> } > >> } else { > >> @@ -694,6 +696,7 @@ static void net_init_tap_one(const > >> NetdevTapOptions *tap, NetClientState *peer, > >> if (vhostfd < 0) { > >> error_setg_errno(errp, errno, > >> "tap: open vhost char device > >> failed"); > >> + *vhost_init_failed = true; > >> return; > >> } > >> fcntl(vhostfd, F_SETFL, O_NONBLOCK); @@ -704,6 +707,7 > >> @@ static void net_init_tap_one(const NetdevTapOptions *tap, > NetClientState *peer, > >> if (!s->vhost_net) { > >> error_setg(errp, > >> "vhost-net requested but could not be > >> initialized"); > >> + *vhost_init_failed = true; > > Why not simply check s->vhost_net after call net_init_tap_one()? s->vhost_net is always NULL if net_init_tap_one() failed, it can't distinguish failure reasons. fd should be closed in these two cases: (1) tap_set_sndbuf() failed, regardless of whether having vhost or vhostforce flag (2) with vhostforce flag fd should not be closed if tap_set_sndbuf() succeeded and vhost init failed without vhostforce flag. Regards, Jay > > Thanks > > >> return; > >> } > >> } else if (vhostfdname) { > >> @@ -748,6 +752,7 @@ int net_init_tap(const Netdev *netdev, const char > *name, > >> Error *err = NULL; > >> const char *vhostfdname; > >> char ifname[128]; > >> + bool vhost_init_failed = false; > >> > >> assert(netdev->type == NET_CLIENT_DRIVER_TAP); > >> tap = &netdev->u.tap; > >> @@ -783,7 +788,7 @@ int net_init_tap(const Netdev *netdev, const char > >> *name, > >> > >> net_init_tap_one(tap, peer, "tap", name, NULL, > >> script, downscript, > >> - vhostfdname, vnet_hdr, fd, &err); > >> + vhostfdname, vnet_hdr, fd, &err, > >> + &vhost_init_failed); > >> if (err) { > >> error_propagate(errp, err); > >> return -1; > >> @@ -835,7 +840,7 @@ int net_init_tap(const Netdev *netdev, const char > *name, > >> net_init_tap_one(tap, peer, "tap", name, ifname, > >> script, downscript, > >> tap->has_vhostfds ? vhost_fds[i] : NULL, > >> - vnet_hdr, fd, &err); > >> + vnet_hdr, fd, &err, > >> + &vhost_init_failed); > >> if (err) { > >> error_propagate(errp, err); > >> goto free_fail; > >> @@ -874,10 +879,12 @@ free_fail: > >> > >> net_init_tap_one(tap, peer, "bridge", name, ifname, > >> script, downscript, vhostfdname, > >> - vnet_hdr, fd, &err); > >> + vnet_hdr, fd, &err, &vhost_init_failed); > >> if (err) { > >> error_propagate(errp, err); > >> - close(fd); > >> + if (tap->has_vhostforce && tap->vhostforce && > >> + vhost_init_failed) > >> { > >> + close(fd); > >> + } > > This should be: > > > > if (!vhost_init_failed || (tap->has_vhostforce && tap->vhostforce)) > { > > close(fd); > > } > > > >> return -1; > >> } > >> } else { > >> @@ -913,10 +920,14 @@ free_fail: > >> net_init_tap_one(tap, peer, "tap", name, ifname, > >> i >= 1 ? "no" : script, > >> i >= 1 ? "no" : downscript, > >> - vhostfdname, vnet_hdr, fd, &err); > >> + vhostfdname, vnet_hdr, fd, &err, > >> + &vhost_init_failed); > >> if (err) { > >> error_propagate(errp, err); > >> - close(fd); > >> + if (tap->has_vhostforce && tap->vhostforce && > >> + vhost_init_failed) { > >> + close(fd); > >> + } > > Same here, this should be: > > > > if (!vhost_init_failed || (tap->has_vhostforce && tap- > >vhostforce)) { > > close(fd); > > } > > > >> return -1; > >> } > >> } > >> -- > >> 1.8.3.1 > >> > >
On 2018年01月10日 15:39, Zhoujian (jay) wrote: >>>> + *vhost_init_failed = true; >> Why not simply check s->vhost_net after call net_init_tap_one()? > s->vhost_net is always NULL if net_init_tap_one() failed, it can't distinguish > failure reasons. On which condition net_init_tap_one() fail but s->vhost_net is set? Thanks
Hi Jason, > -----Original Message----- > From: Jason Wang [mailto:jasowang@redhat.com] > Sent: Thursday, January 11, 2018 11:35 AM > To: Zhoujian (jay) <jianjay.zhou@huawei.com>; qemu-devel@nongnu.org > Cc: Huangweidong (C) <weidong.huang@huawei.com>; mst@redhat.com; wangxin (U) > <wangxinxin.wang@huawei.com>; Gonglei (Arei) <arei.gonglei@huawei.com>; > imammedo@redhat.com; Liuzhe (Ahriy, Euler) <liuzhe13@huawei.com> > Subject: Re: [Qemu-devel] [PATCH v5 2/4][RFC] tap: do not close fd if only > vhost failed to initialize > > > > On 2018年01月10日 15:39, Zhoujian (jay) wrote: > >>>> + *vhost_init_failed = true; > >> Why not simply check s->vhost_net after call net_init_tap_one()? > > s->vhost_net is always NULL if net_init_tap_one() failed, it can't > distinguish > > failure reasons. > > On which condition net_init_tap_one() fail but s->vhost_net is set? No, it does not exist, so we could not use s->vhost_net to decide whether close the fd of tap when error occurred. Maybe the patch below will be much better to understand, please have a look. diff --git a/net/tap.c b/net/tap.c index 979e622..a5c5111 100644 --- a/net/tap.c +++ b/net/tap.c @@ -642,7 +642,8 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, const char *model, const char *name, const char *ifname, const char *script, const char *downscript, const char *vhostfdname, - int vnet_hdr, int fd, Error **errp) + int vnet_hdr, int fd, Error **errp, + bool *error_is_set_sndbuf) { Error *err = NULL; TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); @@ -651,6 +652,9 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, tap_set_sndbuf(s->fd, tap, &err); if (err) { error_propagate(errp, err); + if (error_is_set_sndbuf) { + *error_is_set_sndbuf = true; + } return; } @@ -748,6 +752,7 @@ int net_init_tap(const Netdev *netdev, const char *name, Error *err = NULL; const char *vhostfdname; char ifname[128]; + bool error_is_set_sndbuf = false; assert(netdev->type == NET_CLIENT_DRIVER_TAP); tap = &netdev->u.tap; @@ -783,7 +788,7 @@ int net_init_tap(const Netdev *netdev, const char *name, net_init_tap_one(tap, peer, "tap", name, NULL, script, downscript, - vhostfdname, vnet_hdr, fd, &err); + vhostfdname, vnet_hdr, fd, &err, NULL); if (err) { error_propagate(errp, err); return -1; @@ -835,7 +840,7 @@ int net_init_tap(const Netdev *netdev, const char *name, net_init_tap_one(tap, peer, "tap", name, ifname, script, downscript, tap->has_vhostfds ? vhost_fds[i] : NULL, - vnet_hdr, fd, &err); + vnet_hdr, fd, &err, NULL); if (err) { error_propagate(errp, err); goto free_fail; @@ -874,10 +879,13 @@ free_fail: net_init_tap_one(tap, peer, "bridge", name, ifname, script, downscript, vhostfdname, - vnet_hdr, fd, &err); + vnet_hdr, fd, &err, &error_is_set_sndbuf); if (err) { error_propagate(errp, err); - close(fd); + if (error_is_set_sndbuf || (tap->has_vhostforce && + tap->vhostforce)) { + close(fd); + } return -1; } } else { @@ -913,10 +921,14 @@ free_fail: net_init_tap_one(tap, peer, "tap", name, ifname, i >= 1 ? "no" : script, i >= 1 ? "no" : downscript, - vhostfdname, vnet_hdr, fd, &err); + vhostfdname, vnet_hdr, fd, &err, + &error_is_set_sndbuf); if (err) { error_propagate(errp, err); - close(fd); + if (error_is_set_sndbuf || (tap->has_vhostforce && + tap->vhostforce)) { + close(fd); + } return -1; } } PS: I think I do not express the meaning clearly... I can express it in Chinese in private if necessary Regards, Jay
On 2018年01月11日 11:54, Zhoujian (jay) wrote: > Hi Jason, > >> -----Original Message----- >> From: Jason Wang [mailto:jasowang@redhat.com] >> Sent: Thursday, January 11, 2018 11:35 AM >> To: Zhoujian (jay) <jianjay.zhou@huawei.com>; qemu-devel@nongnu.org >> Cc: Huangweidong (C) <weidong.huang@huawei.com>; mst@redhat.com; wangxin (U) >> <wangxinxin.wang@huawei.com>; Gonglei (Arei) <arei.gonglei@huawei.com>; >> imammedo@redhat.com; Liuzhe (Ahriy, Euler) <liuzhe13@huawei.com> >> Subject: Re: [Qemu-devel] [PATCH v5 2/4][RFC] tap: do not close fd if only >> vhost failed to initialize >> >> >> >> On 2018年01月10日 15:39, Zhoujian (jay) wrote: >>>>>> + *vhost_init_failed = true; >>>> Why not simply check s->vhost_net after call net_init_tap_one()? >>> s->vhost_net is always NULL if net_init_tap_one() failed, it can't >> distinguish >>> failure reasons. >> On which condition net_init_tap_one() fail but s->vhost_net is set? > No, it does not exist, so we could not use s->vhost_net to decide > whether close the fd of tap when error occurred. > > > Maybe the patch below will be much better to understand, please have a look. > > diff --git a/net/tap.c b/net/tap.c > index 979e622..a5c5111 100644 > --- a/net/tap.c > +++ b/net/tap.c > @@ -642,7 +642,8 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, > const char *model, const char *name, > const char *ifname, const char *script, > const char *downscript, const char *vhostfdname, > - int vnet_hdr, int fd, Error **errp) > + int vnet_hdr, int fd, Error **errp, > + bool *error_is_set_sndbuf) > { > Error *err = NULL; > TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); > @@ -651,6 +652,9 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, > tap_set_sndbuf(s->fd, tap, &err); > if (err) { > error_propagate(errp, err); > + if (error_is_set_sndbuf) { > + *error_is_set_sndbuf = true; > + } > return; > } > > @@ -748,6 +752,7 @@ int net_init_tap(const Netdev *netdev, const char *name, > Error *err = NULL; > const char *vhostfdname; > char ifname[128]; > + bool error_is_set_sndbuf = false; > > assert(netdev->type == NET_CLIENT_DRIVER_TAP); > tap = &netdev->u.tap; > @@ -783,7 +788,7 @@ int net_init_tap(const Netdev *netdev, const char *name, > > net_init_tap_one(tap, peer, "tap", name, NULL, > script, downscript, > - vhostfdname, vnet_hdr, fd, &err); > + vhostfdname, vnet_hdr, fd, &err, NULL); > if (err) { > error_propagate(errp, err); > return -1; > @@ -835,7 +840,7 @@ int net_init_tap(const Netdev *netdev, const char *name, > net_init_tap_one(tap, peer, "tap", name, ifname, > script, downscript, > tap->has_vhostfds ? vhost_fds[i] : NULL, > - vnet_hdr, fd, &err); > + vnet_hdr, fd, &err, NULL); > if (err) { > error_propagate(errp, err); > goto free_fail; > @@ -874,10 +879,13 @@ free_fail: > > net_init_tap_one(tap, peer, "bridge", name, ifname, > script, downscript, vhostfdname, > - vnet_hdr, fd, &err); > + vnet_hdr, fd, &err, &error_is_set_sndbuf); > if (err) { > error_propagate(errp, err); > - close(fd); > + if (error_is_set_sndbuf || (tap->has_vhostforce && > + tap->vhostforce)) { > + close(fd); > + } > return -1; > } > } else { > @@ -913,10 +921,14 @@ free_fail: > net_init_tap_one(tap, peer, "tap", name, ifname, > i >= 1 ? "no" : script, > i >= 1 ? "no" : downscript, > - vhostfdname, vnet_hdr, fd, &err); > + vhostfdname, vnet_hdr, fd, &err, > + &error_is_set_sndbuf); > if (err) { > error_propagate(errp, err); > - close(fd); > + if (error_is_set_sndbuf || (tap->has_vhostforce && > + tap->vhostforce)) { > + close(fd); > + } > return -1; > } > } > > > > PS: I think I do not express the meaning clearly... I can express it in > Chinese in private if necessary > > Regards, > Jay That's kind of ugly. I would suggest do all the correct thing in net_tap_init_one(). Thanks
> -----Original Message----- > From: Jason Wang [mailto:jasowang@redhat.com] > Sent: Thursday, January 11, 2018 6:30 PM > To: Zhoujian (jay) <jianjay.zhou@huawei.com>; qemu-devel@nongnu.org > Cc: Huangweidong (C) <weidong.huang@huawei.com>; mst@redhat.com; wangxin (U) > <wangxinxin.wang@huawei.com>; Gonglei (Arei) <arei.gonglei@huawei.com>; > imammedo@redhat.com; Liuzhe (Ahriy, Euler) <liuzhe13@huawei.com> > Subject: Re: [Qemu-devel] [PATCH v5 2/4][RFC] tap: do not close fd if only > vhost failed to initialize > > > > On 2018年01月11日 11:54, Zhoujian (jay) wrote: > > Hi Jason, > > > >> -----Original Message----- > >> From: Jason Wang [mailto:jasowang@redhat.com] > >> Sent: Thursday, January 11, 2018 11:35 AM > >> To: Zhoujian (jay) <jianjay.zhou@huawei.com>; qemu-devel@nongnu.org > >> Cc: Huangweidong (C) <weidong.huang@huawei.com>; mst@redhat.com; > >> wangxin (U) <wangxinxin.wang@huawei.com>; Gonglei (Arei) > >> <arei.gonglei@huawei.com>; imammedo@redhat.com; Liuzhe (Ahriy, Euler) > >> <liuzhe13@huawei.com> > >> Subject: Re: [Qemu-devel] [PATCH v5 2/4][RFC] tap: do not close fd if > >> only vhost failed to initialize > >> > >> > >> > >> On 2018年01月10日 15:39, Zhoujian (jay) wrote: > >>>>>> + *vhost_init_failed = true; > >>>> Why not simply check s->vhost_net after call net_init_tap_one()? > >>> s->vhost_net is always NULL if net_init_tap_one() failed, it can't > >> distinguish > >>> failure reasons. > >> On which condition net_init_tap_one() fail but s->vhost_net is set? > > No, it does not exist, so we could not use s->vhost_net to decide > > whether close the fd of tap when error occurred. > > > > > > Maybe the patch below will be much better to understand, please have a look. > > > > diff --git a/net/tap.c b/net/tap.c > > index 979e622..a5c5111 100644 > > --- a/net/tap.c > > +++ b/net/tap.c > > @@ -642,7 +642,8 @@ static void net_init_tap_one(const NetdevTapOptions > *tap, NetClientState *peer, > > const char *model, const char *name, > > const char *ifname, const char *script, > > const char *downscript, const char > *vhostfdname, > > - int vnet_hdr, int fd, Error **errp) > > + int vnet_hdr, int fd, Error **errp, > > + bool *error_is_set_sndbuf) > > { > > Error *err = NULL; > > TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); > > @@ -651,6 +652,9 @@ static void net_init_tap_one(const NetdevTapOptions > *tap, NetClientState *peer, > > tap_set_sndbuf(s->fd, tap, &err); > > if (err) { > > error_propagate(errp, err); > > + if (error_is_set_sndbuf) { > > + *error_is_set_sndbuf = true; > > + } > > return; > > } > > > > @@ -748,6 +752,7 @@ int net_init_tap(const Netdev *netdev, const char *name, > > Error *err = NULL; > > const char *vhostfdname; > > char ifname[128]; > > + bool error_is_set_sndbuf = false; > > > > assert(netdev->type == NET_CLIENT_DRIVER_TAP); > > tap = &netdev->u.tap; > > @@ -783,7 +788,7 @@ int net_init_tap(const Netdev *netdev, const char > > *name, > > > > net_init_tap_one(tap, peer, "tap", name, NULL, > > script, downscript, > > - vhostfdname, vnet_hdr, fd, &err); > > + vhostfdname, vnet_hdr, fd, &err, NULL); > > if (err) { > > error_propagate(errp, err); > > return -1; > > @@ -835,7 +840,7 @@ int net_init_tap(const Netdev *netdev, const char *name, > > net_init_tap_one(tap, peer, "tap", name, ifname, > > script, downscript, > > tap->has_vhostfds ? vhost_fds[i] : NULL, > > - vnet_hdr, fd, &err); > > + vnet_hdr, fd, &err, NULL); > > if (err) { > > error_propagate(errp, err); > > goto free_fail; > > @@ -874,10 +879,13 @@ free_fail: > > > > net_init_tap_one(tap, peer, "bridge", name, ifname, > > script, downscript, vhostfdname, > > - vnet_hdr, fd, &err); > > + vnet_hdr, fd, &err, &error_is_set_sndbuf); > > if (err) { > > error_propagate(errp, err); > > - close(fd); > > + if (error_is_set_sndbuf || (tap->has_vhostforce && > > + tap->vhostforce)) { > > + close(fd); > > + } > > return -1; > > } > > } else { > > @@ -913,10 +921,14 @@ free_fail: > > net_init_tap_one(tap, peer, "tap", name, ifname, > > i >= 1 ? "no" : script, > > i >= 1 ? "no" : downscript, > > - vhostfdname, vnet_hdr, fd, &err); > > + vhostfdname, vnet_hdr, fd, &err, > > + &error_is_set_sndbuf); > > if (err) { > > error_propagate(errp, err); > > - close(fd); > > + if (error_is_set_sndbuf || (tap->has_vhostforce && > > + tap->vhostforce)) { > > + close(fd); > > + } > > return -1; > > } > > } > > > > > > > > PS: I think I do not express the meaning clearly... I can express it > > in Chinese in private if necessary > > > > Regards, > > Jay > > That's kind of ugly. Oops... > > I would suggest do all the correct thing in net_tap_init_one(). Yes, you're right, we could do it better, :) How about this one(I have done some tests, it works): --- diff --git a/net/tap.c b/net/tap.c index 979e622..3ed72eb 100644 --- a/net/tap.c +++ b/net/tap.c @@ -651,6 +651,9 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, tap_set_sndbuf(s->fd, tap, &err); if (err) { error_propagate(errp, err); + if (!tap->has_fd && !tap->has_fds) { + close(fd); + } return; } @@ -687,14 +690,14 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err); if (vhostfd == -1) { error_propagate(errp, err); - return; + goto cleanup; } } else { vhostfd = open("/dev/vhost-net", O_RDWR); if (vhostfd < 0) { error_setg_errno(errp, errno, "tap: open vhost char device failed"); - return; + goto cleanup; } fcntl(vhostfd, F_SETFL, O_NONBLOCK); } @@ -704,11 +707,18 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, if (!s->vhost_net) { error_setg(errp, "vhost-net requested but could not be initialized"); - return; + goto cleanup; } } else if (vhostfdname) { error_setg(errp, "vhostfd(s)= is not valid without vhost"); } + +cleanup: + if (!tap->has_fd && !tap->has_fds && tap->has_vhostforce && + tap->vhostforce) { + close(fd); + } + return; } static int get_fds(char *str, char *fds[], int max) @@ -877,7 +887,6 @@ free_fail: vnet_hdr, fd, &err); if (err) { error_propagate(errp, err); - close(fd); return -1; } } else { @@ -916,7 +925,6 @@ free_fail: vhostfdname, vnet_hdr, fd, &err); if (err) { error_propagate(errp, err); - close(fd); return -1; } } --- > > Thanks
diff --git a/net/tap.c b/net/tap.c index 979e622..03f226f 100644 --- a/net/tap.c +++ b/net/tap.c @@ -642,7 +642,8 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, const char *model, const char *name, const char *ifname, const char *script, const char *downscript, const char *vhostfdname, - int vnet_hdr, int fd, Error **errp) + int vnet_hdr, int fd, Error **errp, + bool *vhost_init_failed) { Error *err = NULL; TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr); @@ -687,6 +688,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, vhostfd = monitor_fd_param(cur_mon, vhostfdname, &err); if (vhostfd == -1) { error_propagate(errp, err); + *vhost_init_failed = true; return; } } else { @@ -694,6 +696,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, if (vhostfd < 0) { error_setg_errno(errp, errno, "tap: open vhost char device failed"); + *vhost_init_failed = true; return; } fcntl(vhostfd, F_SETFL, O_NONBLOCK); @@ -704,6 +707,7 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer, if (!s->vhost_net) { error_setg(errp, "vhost-net requested but could not be initialized"); + *vhost_init_failed = true; return; } } else if (vhostfdname) { @@ -748,6 +752,7 @@ int net_init_tap(const Netdev *netdev, const char *name, Error *err = NULL; const char *vhostfdname; char ifname[128]; + bool vhost_init_failed = false; assert(netdev->type == NET_CLIENT_DRIVER_TAP); tap = &netdev->u.tap; @@ -783,7 +788,7 @@ int net_init_tap(const Netdev *netdev, const char *name, net_init_tap_one(tap, peer, "tap", name, NULL, script, downscript, - vhostfdname, vnet_hdr, fd, &err); + vhostfdname, vnet_hdr, fd, &err, &vhost_init_failed); if (err) { error_propagate(errp, err); return -1; @@ -835,7 +840,7 @@ int net_init_tap(const Netdev *netdev, const char *name, net_init_tap_one(tap, peer, "tap", name, ifname, script, downscript, tap->has_vhostfds ? vhost_fds[i] : NULL, - vnet_hdr, fd, &err); + vnet_hdr, fd, &err, &vhost_init_failed); if (err) { error_propagate(errp, err); goto free_fail; @@ -874,10 +879,12 @@ free_fail: net_init_tap_one(tap, peer, "bridge", name, ifname, script, downscript, vhostfdname, - vnet_hdr, fd, &err); + vnet_hdr, fd, &err, &vhost_init_failed); if (err) { error_propagate(errp, err); - close(fd); + if (tap->has_vhostforce && tap->vhostforce && vhost_init_failed) { + close(fd); + } return -1; } } else { @@ -913,10 +920,14 @@ free_fail: net_init_tap_one(tap, peer, "tap", name, ifname, i >= 1 ? "no" : script, i >= 1 ? "no" : downscript, - vhostfdname, vnet_hdr, fd, &err); + vhostfdname, vnet_hdr, fd, &err, + &vhost_init_failed); if (err) { error_propagate(errp, err); - close(fd); + if (tap->has_vhostforce && tap->vhostforce && + vhost_init_failed) { + close(fd); + } return -1; } }
Making the followed up device_add to fall back to userspace virtio when netdev_add fails if vhost force flag does not set. Suggested-by: Michael S. Tsirkin <mst@redhat.com> Suggested-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com> --- net/tap.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-)