Changes in v11 - Drop change log histroy in commit log Changes in v10 - Drop comments about lun - Add Enable VIRTIO_SCSI_F_HOTPLUG to this series Changes in v9 - Drop tcm_vhost_check_feature - Add Refactor the lock nesting rule to this sereis Asias He (4): tcm_vhost: Refactor the lock nesting rule tcm_vhost: Add hotplug/hotunplug support tcm_vhost: Add ioctl to get and set events missed flag tcm_vhost: Enable VIRTIO_SCSI_F_HOTPLUG drivers/vhost/tcm_vhost.c | 262 +++++++++++++++++++++++++++++++++++++++++++--- drivers/vhost/tcm_vhost.h | 13 +++ 2 files changed, 259 insertions(+), 16 deletions(-) -- 1.8.1.4
We want to use tcm_vhost_mutex to make sure hotplug/hotunplug will not happen when set_endpoint/clear_endpoint is in process. Signed-off-by: Asias He <asias at redhat.com> --- drivers/vhost/tcm_vhost.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-) diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c index 957a0b9..822cd1f 100644 --- a/drivers/vhost/tcm_vhost.c +++ b/drivers/vhost/tcm_vhost.c @@ -808,6 +808,9 @@ static void vhost_scsi_flush(struct vhost_scsi *vs) /* * Called from vhost_scsi_ioctl() context to walk the list of available * tcm_vhost_tpg with an active struct tcm_vhost_nexus + * + * The lock nesting rule is: + * tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex */ static int vhost_scsi_set_endpoint( struct vhost_scsi *vs, @@ -820,26 +823,27 @@ static int vhost_scsi_set_endpoint( int index, ret, i, len; bool match = false; + mutex_lock(&tcm_vhost_mutex); mutex_lock(&vs->dev.mutex); + /* Verify that ring has been setup correctly. */ for (index = 0; index < vs->dev.nvqs; ++index) { /* Verify that ring has been setup correctly. */ if (!vhost_vq_access_ok(&vs->vqs[index])) { - mutex_unlock(&vs->dev.mutex); - return -EFAULT; + ret = -EFAULT; + goto out; } } len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET; vs_tpg = kzalloc(len, GFP_KERNEL); if (!vs_tpg) { - mutex_unlock(&vs->dev.mutex); - return -ENOMEM; + ret = -ENOMEM; + goto out; } if (vs->vs_tpg) memcpy(vs_tpg, vs->vs_tpg, len); - mutex_lock(&tcm_vhost_mutex); list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) { mutex_lock(&tv_tpg->tv_tpg_mutex); if (!tv_tpg->tpg_nexus) { @@ -854,11 +858,10 @@ static int vhost_scsi_set_endpoint( if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) { if (vs->vs_tpg && vs->vs_tpg[tv_tpg->tport_tpgt]) { - mutex_unlock(&tv_tpg->tv_tpg_mutex); - mutex_unlock(&tcm_vhost_mutex); - mutex_unlock(&vs->dev.mutex); kfree(vs_tpg); - return -EEXIST; + mutex_unlock(&tv_tpg->tv_tpg_mutex); + ret = -EEXIST; + goto out; } tv_tpg->tv_tpg_vhost_count++; vs_tpg[tv_tpg->tport_tpgt] = tv_tpg; @@ -867,7 +870,6 @@ static int vhost_scsi_set_endpoint( } mutex_unlock(&tv_tpg->tv_tpg_mutex); } - mutex_unlock(&tcm_vhost_mutex); if (match) { memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn, @@ -893,7 +895,9 @@ static int vhost_scsi_set_endpoint( kfree(vs->vs_tpg); vs->vs_tpg = vs_tpg; +out: mutex_unlock(&vs->dev.mutex); + mutex_unlock(&tcm_vhost_mutex); return ret; } @@ -908,6 +912,7 @@ static int vhost_scsi_clear_endpoint( int index, ret, i; u8 target; + mutex_lock(&tcm_vhost_mutex); mutex_lock(&vs->dev.mutex); /* Verify that ring has been setup correctly. */ for (index = 0; index < vs->dev.nvqs; ++index) { @@ -918,8 +923,8 @@ static int vhost_scsi_clear_endpoint( } if (!vs->vs_tpg) { - mutex_unlock(&vs->dev.mutex); - return 0; + ret = 0; + goto err_dev; } for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) { @@ -965,13 +970,14 @@ static int vhost_scsi_clear_endpoint( kfree(vs->vs_tpg); vs->vs_tpg = NULL; mutex_unlock(&vs->dev.mutex); - + mutex_unlock(&tcm_vhost_mutex); return 0; err_tpg: mutex_unlock(&tv_tpg->tv_tpg_mutex); err_dev: mutex_unlock(&vs->dev.mutex); + mutex_unlock(&tcm_vhost_mutex); return ret; } -- 1.8.1.4
In commit 365a7150094 ([SCSI] virtio-scsi: hotplug support for virtio-scsi), hotplug support is added to virtio-scsi. This patch adds hotplug and hotunplug support to tcm_vhost. You can create or delete a LUN in targetcli to hotplug or hotunplug a LUN in guest. Signed-off-by: Asias He <asias at redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha at redhat.com> --- drivers/vhost/tcm_vhost.c | 210 +++++++++++++++++++++++++++++++++++++++++++++- drivers/vhost/tcm_vhost.h | 10 +++ 2 files changed, 218 insertions(+), 2 deletions(-) diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c index 822cd1f..5340fd7 100644 --- a/drivers/vhost/tcm_vhost.c +++ b/drivers/vhost/tcm_vhost.c @@ -71,6 +71,7 @@ enum { #define VHOST_SCSI_MAX_TARGET 256 #define VHOST_SCSI_MAX_VQ 128 +#define VHOST_SCSI_MAX_EVENT 128 struct vhost_scsi { /* Protected by vhost_scsi->dev.mutex */ @@ -82,6 +83,12 @@ struct vhost_scsi { struct vhost_work vs_completion_work; /* cmd completion work item */ struct llist_head vs_completion_list; /* cmd completion queue */ + + struct vhost_work vs_event_work; /* evt injection work item */ + struct llist_head vs_event_list; /* evt injection queue */ + + bool vs_events_missed; /* any missed events, protected by vq->mutex */ + int vs_events_nr; /* num of pending events, protected by vq->mutex */ }; /* Local pointer to allocated TCM configfs fabric module */ @@ -349,6 +356,37 @@ static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd) return 0; } +static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt) +{ + vs->vs_events_nr--; + kfree(evt); +} + +static struct tcm_vhost_evt *tcm_vhost_allocate_evt(struct vhost_scsi *vs, + u32 event, u32 reason) +{ + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + struct tcm_vhost_evt *evt; + + if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) { + vs->vs_events_missed = true; + return NULL; + } + + evt = kzalloc(sizeof(*evt), GFP_KERNEL); + if (!evt) { + vq_err(vq, "Failed to allocate tcm_vhost_evt\n"); + vs->vs_events_missed = true; + return NULL; + } + + evt->event.event = event; + evt->event.reason = reason; + vs->vs_events_nr++; + + return evt; +} + static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd) { struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd; @@ -367,6 +405,75 @@ static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd) kfree(tv_cmd); } +static void tcm_vhost_do_evt_work(struct vhost_scsi *vs, + struct tcm_vhost_evt *evt) +{ + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + struct virtio_scsi_event *event = &evt->event; + struct virtio_scsi_event __user *eventp; + unsigned out, in; + int head, ret; + + if (!vq->private_data) { + vs->vs_events_missed = true; + return; + } + +again: + vhost_disable_notify(&vs->dev, vq); + head = vhost_get_vq_desc(&vs->dev, vq, vq->iov, + ARRAY_SIZE(vq->iov), &out, &in, + NULL, NULL); + if (head < 0) { + vs->vs_events_missed = true; + return; + } + if (head == vq->num) { + if (vhost_enable_notify(&vs->dev, vq)) + goto again; + vs->vs_events_missed = true; + return; + } + + if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) { + vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n", + vq->iov[out].iov_len); + vs->vs_events_missed = true; + return; + } + + if (vs->vs_events_missed) { + event->event |= VIRTIO_SCSI_T_EVENTS_MISSED; + vs->vs_events_missed = false; + } + + eventp = vq->iov[out].iov_base; + ret = __copy_to_user(eventp, event, sizeof(*event)); + if (!ret) + vhost_add_used_and_signal(&vs->dev, vq, head, 0); + else + vq_err(vq, "Faulted on tcm_vhost_send_event\n"); +} + +static void tcm_vhost_evt_work(struct vhost_work *work) +{ + struct vhost_scsi *vs = container_of(work, struct vhost_scsi, + vs_event_work); + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + struct tcm_vhost_evt *evt; + struct llist_node *llnode; + + mutex_lock(&vq->mutex); + llnode = llist_del_all(&vs->vs_event_list); + while (llnode) { + evt = llist_entry(llnode, struct tcm_vhost_evt, list); + llnode = llist_next(llnode); + tcm_vhost_do_evt_work(vs, evt); + tcm_vhost_free_evt(vs, evt); + } + mutex_unlock(&vq->mutex); +} + /* Fill in status and signal that we are done processing this command * * This is scheduled in the vhost work queue so we are called with the owner @@ -777,9 +884,46 @@ static void vhost_scsi_ctl_handle_kick(struct vhost_work *work) pr_debug("%s: The handling func for control queue.\n", __func__); } +static void tcm_vhost_send_evt(struct vhost_scsi *vs, struct tcm_vhost_tpg *tpg, + struct se_lun *lun, u32 event, u32 reason) +{ + struct tcm_vhost_evt *evt; + + evt = tcm_vhost_allocate_evt(vs, event, reason); + if (!evt) + return; + + if (tpg && lun) { + /* TODO: share lun setup code with virtio-scsi.ko */ + /* + * Note: evt->event is zeroed when we allocate it and + * lun[4-7] need to be zero according to virtio-scsi spec. + */ + evt->event.lun[0] = 0x01; + evt->event.lun[1] = tpg->tport_tpgt & 0xFF; + if (lun->unpacked_lun >= 256) + evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ; + evt->event.lun[3] = lun->unpacked_lun & 0xFF; + } + + llist_add(&evt->list, &vs->vs_event_list); + vhost_work_queue(&vs->dev, &vs->vs_event_work); +} + static void vhost_scsi_evt_handle_kick(struct vhost_work *work) { - pr_debug("%s: The handling func for event queue.\n", __func__); + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev); + + mutex_lock(&vq->mutex); + if (!vq->private_data) + goto out; + + if (vs->vs_events_missed) + tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0); +out: + mutex_unlock(&vq->mutex); } static void vhost_scsi_handle_kick(struct vhost_work *work) @@ -803,6 +947,7 @@ static void vhost_scsi_flush(struct vhost_scsi *vs) for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) vhost_scsi_flush_vq(vs, i); vhost_work_flush(&vs->dev, &vs->vs_completion_work); + vhost_work_flush(&vs->dev, &vs->vs_event_work); } /* @@ -864,6 +1009,7 @@ static int vhost_scsi_set_endpoint( goto out; } tv_tpg->tv_tpg_vhost_count++; + tv_tpg->vhost_scsi = vs; vs_tpg[tv_tpg->tport_tpgt] = tv_tpg; smp_mb__after_atomic_inc(); match = true; @@ -949,6 +1095,7 @@ static int vhost_scsi_clear_endpoint( goto err_tpg; } tv_tpg->tv_tpg_vhost_count--; + tv_tpg->vhost_scsi = NULL; vs->vs_tpg[target] = NULL; match = true; mutex_unlock(&tv_tpg->tv_tpg_mutex); @@ -969,6 +1116,7 @@ static int vhost_scsi_clear_endpoint( vhost_scsi_flush(vs); kfree(vs->vs_tpg); vs->vs_tpg = NULL; + WARN_ON(vs->vs_events_nr); mutex_unlock(&vs->dev.mutex); mutex_unlock(&tcm_vhost_mutex); return 0; @@ -1009,6 +1157,10 @@ static int vhost_scsi_open(struct inode *inode, struct file *f) return -ENOMEM; vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work); + vhost_work_init(&s->vs_event_work, tcm_vhost_evt_work); + + s->vs_events_nr = 0; + s->vs_events_missed = false; s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick; s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick; @@ -1035,6 +1187,8 @@ static int vhost_scsi_release(struct inode *inode, struct file *f) vhost_scsi_clear_endpoint(s, &t); vhost_dev_stop(&s->dev); vhost_dev_cleanup(&s->dev, false); + /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */ + vhost_scsi_flush(s); kfree(s); return 0; } @@ -1139,28 +1293,80 @@ static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport) return "Unknown"; } +static void tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg, + struct se_lun *lun, bool plug) +{ + + struct vhost_scsi *vs = tpg->vhost_scsi; + struct vhost_virtqueue *vq; + u32 reason; + + if (!vs) + return; + + mutex_lock(&vs->dev.mutex); + if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) { + mutex_unlock(&vs->dev.mutex); + return; + } + + if (plug) + reason = VIRTIO_SCSI_EVT_RESET_RESCAN; + else + reason = VIRTIO_SCSI_EVT_RESET_REMOVED; + + vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + mutex_lock(&vq->mutex); + tcm_vhost_send_evt(vs, tpg, lun, + VIRTIO_SCSI_T_TRANSPORT_RESET, reason); + mutex_unlock(&vq->mutex); + mutex_unlock(&vs->dev.mutex); +} + +static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) +{ + tcm_vhost_do_plug(tpg, lun, true); +} + +static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) +{ + tcm_vhost_do_plug(tpg, lun, false); +} + static int tcm_vhost_port_link(struct se_portal_group *se_tpg, struct se_lun *lun) { struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, struct tcm_vhost_tpg, se_tpg); + mutex_lock(&tcm_vhost_mutex); + mutex_lock(&tv_tpg->tv_tpg_mutex); tv_tpg->tv_tpg_port_count++; mutex_unlock(&tv_tpg->tv_tpg_mutex); + tcm_vhost_hotplug(tv_tpg, lun); + + mutex_unlock(&tcm_vhost_mutex); + return 0; } static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg, - struct se_lun *se_lun) + struct se_lun *lun) { struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, struct tcm_vhost_tpg, se_tpg); + mutex_lock(&tcm_vhost_mutex); + mutex_lock(&tv_tpg->tv_tpg_mutex); tv_tpg->tv_tpg_port_count--; mutex_unlock(&tv_tpg->tv_tpg_mutex); + + tcm_vhost_hotunplug(tv_tpg, lun); + + mutex_unlock(&tcm_vhost_mutex); } static struct se_node_acl *tcm_vhost_make_nodeacl( diff --git a/drivers/vhost/tcm_vhost.h b/drivers/vhost/tcm_vhost.h index 1d2ae7a..a545a5b 100644 --- a/drivers/vhost/tcm_vhost.h +++ b/drivers/vhost/tcm_vhost.h @@ -53,6 +53,7 @@ struct tcm_vhost_nacl { struct se_node_acl se_node_acl; }; +struct vhost_scsi; struct tcm_vhost_tpg { /* Vhost port target portal group tag for TCM */ u16 tport_tpgt; @@ -70,6 +71,8 @@ struct tcm_vhost_tpg { struct tcm_vhost_tport *tport; /* Returned by tcm_vhost_make_tpg() */ struct se_portal_group se_tpg; + /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */ + struct vhost_scsi *vhost_scsi; }; struct tcm_vhost_tport { @@ -83,6 +86,13 @@ struct tcm_vhost_tport { struct se_wwn tport_wwn; }; +struct tcm_vhost_evt { + /* event to be sent to guest */ + struct virtio_scsi_event event; + /* event list, serviced from vhost worker thread */ + struct llist_node list; +}; + /* * As per request from MST, keep TCM_VHOST related ioctl defines out of * linux/vhost.h (user-space) for now.. -- 1.8.1.4
Asias He
2013-Apr-25 07:35 UTC
[PATCH v11 3/4] tcm_vhost: Add ioctl to get and set events missed flag
Signed-off-by: Asias He <asias at redhat.com> --- drivers/vhost/tcm_vhost.c | 17 +++++++++++++++++ drivers/vhost/tcm_vhost.h | 3 +++ 2 files changed, 20 insertions(+) diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c index 5340fd7..07217d8 100644 --- a/drivers/vhost/tcm_vhost.c +++ b/drivers/vhost/tcm_vhost.c @@ -1200,8 +1200,11 @@ static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, struct vhost_scsi_target backend; void __user *argp = (void __user *)arg; u64 __user *featurep = argp; + u32 __user *eventsp = argp; + u32 events_missed; u64 features; int r, abi_version = VHOST_SCSI_ABI_VERSION; + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; switch (ioctl) { case VHOST_SCSI_SET_ENDPOINT: @@ -1222,6 +1225,20 @@ static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, if (copy_to_user(argp, &abi_version, sizeof abi_version)) return -EFAULT; return 0; + case VHOST_SCSI_SET_EVENTS_MISSED: + if (get_user(events_missed, eventsp)) + return -EFAULT; + mutex_lock(&vq->mutex); + vs->vs_events_missed = events_missed; + mutex_unlock(&vq->mutex); + return 0; + case VHOST_SCSI_GET_EVENTS_MISSED: + mutex_lock(&vq->mutex); + events_missed = vs->vs_events_missed; + mutex_unlock(&vq->mutex); + if (put_user(events_missed, eventsp)) + return -EFAULT; + return 0; case VHOST_GET_FEATURES: features = VHOST_SCSI_FEATURES; if (copy_to_user(featurep, &features, sizeof features)) diff --git a/drivers/vhost/tcm_vhost.h b/drivers/vhost/tcm_vhost.h index a545a5b..514b9fd 100644 --- a/drivers/vhost/tcm_vhost.h +++ b/drivers/vhost/tcm_vhost.h @@ -123,3 +123,6 @@ struct vhost_scsi_target { #define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target) /* Changing this breaks userspace. */ #define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int) +/* Set and get the events missed flag */ +#define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32) +#define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32) -- 1.8.1.4
Everything for hotplug is ready. Let's enable the feature bit. Signed-off-by: Asias He <asias at redhat.com> --- drivers/vhost/tcm_vhost.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c index 07217d8..1677238 100644 --- a/drivers/vhost/tcm_vhost.c +++ b/drivers/vhost/tcm_vhost.c @@ -66,7 +66,8 @@ enum { * TODO: debug and remove the workaround. */ enum { - VHOST_SCSI_FEATURES = VHOST_FEATURES & (~VIRTIO_RING_F_EVENT_IDX) + VHOST_SCSI_FEATURES = (VHOST_FEATURES & (~VIRTIO_RING_F_EVENT_IDX)) | + (1ULL << VIRTIO_SCSI_F_HOTPLUG) }; #define VHOST_SCSI_MAX_TARGET 256 -- 1.8.1.4
On Thu, Apr 25, 2013 at 03:35:19PM +0800, Asias He wrote:> Changes in v11 > - Drop change log histroy in commit log > > Changes in v10 > - Drop comments about lun > - Add Enable VIRTIO_SCSI_F_HOTPLUG to this series > > Changes in v9 > - Drop tcm_vhost_check_feature > - Add Refactor the lock nesting rule to this sereis > > Asias He (4): > tcm_vhost: Refactor the lock nesting rule > tcm_vhost: Add hotplug/hotunplug support > tcm_vhost: Add ioctl to get and set events missed flag > tcm_vhost: Enable VIRTIO_SCSI_F_HOTPLUG > > drivers/vhost/tcm_vhost.c | 262 +++++++++++++++++++++++++++++++++++++++++++--- > drivers/vhost/tcm_vhost.h | 13 +++ > 2 files changed, 259 insertions(+), 16 deletions(-)Acked-by: Michael S. Tsirkin <mst at redhat.com>> -- > 1.8.1.4
Michael S. Tsirkin
2013-Apr-25 07:39 UTC
[PATCH v11 1/4] tcm_vhost: Refactor the lock nesting rule
On Thu, Apr 25, 2013 at 03:35:20PM +0800, Asias He wrote:> We want to use tcm_vhost_mutex to make sure hotplug/hotunplug will not > happen when set_endpoint/clear_endpoint is in process. > > Signed-off-by: Asias He <asias at redhat.com>Acked-by: Michael S. Tsirkin <mst at redhat.com>> --- > drivers/vhost/tcm_vhost.c | 32 +++++++++++++++++++------------- > 1 file changed, 19 insertions(+), 13 deletions(-) > > diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c > index 957a0b9..822cd1f 100644 > --- a/drivers/vhost/tcm_vhost.c > +++ b/drivers/vhost/tcm_vhost.c > @@ -808,6 +808,9 @@ static void vhost_scsi_flush(struct vhost_scsi *vs) > /* > * Called from vhost_scsi_ioctl() context to walk the list of available > * tcm_vhost_tpg with an active struct tcm_vhost_nexus > + * > + * The lock nesting rule is: > + * tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex > */ > static int vhost_scsi_set_endpoint( > struct vhost_scsi *vs, > @@ -820,26 +823,27 @@ static int vhost_scsi_set_endpoint( > int index, ret, i, len; > bool match = false; > > + mutex_lock(&tcm_vhost_mutex); > mutex_lock(&vs->dev.mutex); > + > /* Verify that ring has been setup correctly. */ > for (index = 0; index < vs->dev.nvqs; ++index) { > /* Verify that ring has been setup correctly. */ > if (!vhost_vq_access_ok(&vs->vqs[index])) { > - mutex_unlock(&vs->dev.mutex); > - return -EFAULT; > + ret = -EFAULT; > + goto out; > } > } > > len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET; > vs_tpg = kzalloc(len, GFP_KERNEL); > if (!vs_tpg) { > - mutex_unlock(&vs->dev.mutex); > - return -ENOMEM; > + ret = -ENOMEM; > + goto out; > } > if (vs->vs_tpg) > memcpy(vs_tpg, vs->vs_tpg, len); > > - mutex_lock(&tcm_vhost_mutex); > list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) { > mutex_lock(&tv_tpg->tv_tpg_mutex); > if (!tv_tpg->tpg_nexus) { > @@ -854,11 +858,10 @@ static int vhost_scsi_set_endpoint( > > if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) { > if (vs->vs_tpg && vs->vs_tpg[tv_tpg->tport_tpgt]) { > - mutex_unlock(&tv_tpg->tv_tpg_mutex); > - mutex_unlock(&tcm_vhost_mutex); > - mutex_unlock(&vs->dev.mutex); > kfree(vs_tpg); > - return -EEXIST; > + mutex_unlock(&tv_tpg->tv_tpg_mutex); > + ret = -EEXIST; > + goto out; > } > tv_tpg->tv_tpg_vhost_count++; > vs_tpg[tv_tpg->tport_tpgt] = tv_tpg; > @@ -867,7 +870,6 @@ static int vhost_scsi_set_endpoint( > } > mutex_unlock(&tv_tpg->tv_tpg_mutex); > } > - mutex_unlock(&tcm_vhost_mutex); > > if (match) { > memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn, > @@ -893,7 +895,9 @@ static int vhost_scsi_set_endpoint( > kfree(vs->vs_tpg); > vs->vs_tpg = vs_tpg; > > +out: > mutex_unlock(&vs->dev.mutex); > + mutex_unlock(&tcm_vhost_mutex); > return ret; > } > > @@ -908,6 +912,7 @@ static int vhost_scsi_clear_endpoint( > int index, ret, i; > u8 target; > > + mutex_lock(&tcm_vhost_mutex); > mutex_lock(&vs->dev.mutex); > /* Verify that ring has been setup correctly. */ > for (index = 0; index < vs->dev.nvqs; ++index) { > @@ -918,8 +923,8 @@ static int vhost_scsi_clear_endpoint( > } > > if (!vs->vs_tpg) { > - mutex_unlock(&vs->dev.mutex); > - return 0; > + ret = 0; > + goto err_dev; > } > > for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) { > @@ -965,13 +970,14 @@ static int vhost_scsi_clear_endpoint( > kfree(vs->vs_tpg); > vs->vs_tpg = NULL; > mutex_unlock(&vs->dev.mutex); > - > + mutex_unlock(&tcm_vhost_mutex); > return 0; > > err_tpg: > mutex_unlock(&tv_tpg->tv_tpg_mutex); > err_dev: > mutex_unlock(&vs->dev.mutex); > + mutex_unlock(&tcm_vhost_mutex); > return ret; > } > > -- > 1.8.1.4
Michael S. Tsirkin
2013-Apr-25 07:40 UTC
[PATCH v11 2/4] tcm_vhost: Add hotplug/hotunplug support
On Thu, Apr 25, 2013 at 03:35:21PM +0800, Asias He wrote:> In commit 365a7150094 ([SCSI] virtio-scsi: hotplug support for > virtio-scsi), hotplug support is added to virtio-scsi. > > This patch adds hotplug and hotunplug support to tcm_vhost. > > You can create or delete a LUN in targetcli to hotplug or hotunplug a > LUN in guest. > > Signed-off-by: Asias He <asias at redhat.com> > Reviewed-by: Stefan Hajnoczi <stefanha at redhat.com>Acked-by: Michael S. Tsirkin <mst at redhat.com>> --- > drivers/vhost/tcm_vhost.c | 210 +++++++++++++++++++++++++++++++++++++++++++++- > drivers/vhost/tcm_vhost.h | 10 +++ > 2 files changed, 218 insertions(+), 2 deletions(-) > > diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c > index 822cd1f..5340fd7 100644 > --- a/drivers/vhost/tcm_vhost.c > +++ b/drivers/vhost/tcm_vhost.c > @@ -71,6 +71,7 @@ enum { > > #define VHOST_SCSI_MAX_TARGET 256 > #define VHOST_SCSI_MAX_VQ 128 > +#define VHOST_SCSI_MAX_EVENT 128 > > struct vhost_scsi { > /* Protected by vhost_scsi->dev.mutex */ > @@ -82,6 +83,12 @@ struct vhost_scsi { > > struct vhost_work vs_completion_work; /* cmd completion work item */ > struct llist_head vs_completion_list; /* cmd completion queue */ > + > + struct vhost_work vs_event_work; /* evt injection work item */ > + struct llist_head vs_event_list; /* evt injection queue */ > + > + bool vs_events_missed; /* any missed events, protected by vq->mutex */ > + int vs_events_nr; /* num of pending events, protected by vq->mutex */ > }; > > /* Local pointer to allocated TCM configfs fabric module */ > @@ -349,6 +356,37 @@ static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd) > return 0; > } > > +static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt) > +{ > + vs->vs_events_nr--; > + kfree(evt); > +} > + > +static struct tcm_vhost_evt *tcm_vhost_allocate_evt(struct vhost_scsi *vs, > + u32 event, u32 reason) > +{ > + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; > + struct tcm_vhost_evt *evt; > + > + if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) { > + vs->vs_events_missed = true; > + return NULL; > + } > + > + evt = kzalloc(sizeof(*evt), GFP_KERNEL); > + if (!evt) { > + vq_err(vq, "Failed to allocate tcm_vhost_evt\n"); > + vs->vs_events_missed = true; > + return NULL; > + } > + > + evt->event.event = event; > + evt->event.reason = reason; > + vs->vs_events_nr++; > + > + return evt; > +} > + > static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd) > { > struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd; > @@ -367,6 +405,75 @@ static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd) > kfree(tv_cmd); > } > > +static void tcm_vhost_do_evt_work(struct vhost_scsi *vs, > + struct tcm_vhost_evt *evt) > +{ > + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; > + struct virtio_scsi_event *event = &evt->event; > + struct virtio_scsi_event __user *eventp; > + unsigned out, in; > + int head, ret; > + > + if (!vq->private_data) { > + vs->vs_events_missed = true; > + return; > + } > + > +again: > + vhost_disable_notify(&vs->dev, vq); > + head = vhost_get_vq_desc(&vs->dev, vq, vq->iov, > + ARRAY_SIZE(vq->iov), &out, &in, > + NULL, NULL); > + if (head < 0) { > + vs->vs_events_missed = true; > + return; > + } > + if (head == vq->num) { > + if (vhost_enable_notify(&vs->dev, vq)) > + goto again; > + vs->vs_events_missed = true; > + return; > + } > + > + if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) { > + vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n", > + vq->iov[out].iov_len); > + vs->vs_events_missed = true; > + return; > + } > + > + if (vs->vs_events_missed) { > + event->event |= VIRTIO_SCSI_T_EVENTS_MISSED; > + vs->vs_events_missed = false; > + } > + > + eventp = vq->iov[out].iov_base; > + ret = __copy_to_user(eventp, event, sizeof(*event)); > + if (!ret) > + vhost_add_used_and_signal(&vs->dev, vq, head, 0); > + else > + vq_err(vq, "Faulted on tcm_vhost_send_event\n"); > +} > + > +static void tcm_vhost_evt_work(struct vhost_work *work) > +{ > + struct vhost_scsi *vs = container_of(work, struct vhost_scsi, > + vs_event_work); > + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; > + struct tcm_vhost_evt *evt; > + struct llist_node *llnode; > + > + mutex_lock(&vq->mutex); > + llnode = llist_del_all(&vs->vs_event_list); > + while (llnode) { > + evt = llist_entry(llnode, struct tcm_vhost_evt, list); > + llnode = llist_next(llnode); > + tcm_vhost_do_evt_work(vs, evt); > + tcm_vhost_free_evt(vs, evt); > + } > + mutex_unlock(&vq->mutex); > +} > + > /* Fill in status and signal that we are done processing this command > * > * This is scheduled in the vhost work queue so we are called with the owner > @@ -777,9 +884,46 @@ static void vhost_scsi_ctl_handle_kick(struct vhost_work *work) > pr_debug("%s: The handling func for control queue.\n", __func__); > } > > +static void tcm_vhost_send_evt(struct vhost_scsi *vs, struct tcm_vhost_tpg *tpg, > + struct se_lun *lun, u32 event, u32 reason) > +{ > + struct tcm_vhost_evt *evt; > + > + evt = tcm_vhost_allocate_evt(vs, event, reason); > + if (!evt) > + return; > + > + if (tpg && lun) { > + /* TODO: share lun setup code with virtio-scsi.ko */ > + /* > + * Note: evt->event is zeroed when we allocate it and > + * lun[4-7] need to be zero according to virtio-scsi spec. > + */ > + evt->event.lun[0] = 0x01; > + evt->event.lun[1] = tpg->tport_tpgt & 0xFF; > + if (lun->unpacked_lun >= 256) > + evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ; > + evt->event.lun[3] = lun->unpacked_lun & 0xFF; > + } > + > + llist_add(&evt->list, &vs->vs_event_list); > + vhost_work_queue(&vs->dev, &vs->vs_event_work); > +} > + > static void vhost_scsi_evt_handle_kick(struct vhost_work *work) > { > - pr_debug("%s: The handling func for event queue.\n", __func__); > + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, > + poll.work); > + struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev); > + > + mutex_lock(&vq->mutex); > + if (!vq->private_data) > + goto out; > + > + if (vs->vs_events_missed) > + tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0); > +out: > + mutex_unlock(&vq->mutex); > } > > static void vhost_scsi_handle_kick(struct vhost_work *work) > @@ -803,6 +947,7 @@ static void vhost_scsi_flush(struct vhost_scsi *vs) > for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) > vhost_scsi_flush_vq(vs, i); > vhost_work_flush(&vs->dev, &vs->vs_completion_work); > + vhost_work_flush(&vs->dev, &vs->vs_event_work); > } > > /* > @@ -864,6 +1009,7 @@ static int vhost_scsi_set_endpoint( > goto out; > } > tv_tpg->tv_tpg_vhost_count++; > + tv_tpg->vhost_scsi = vs; > vs_tpg[tv_tpg->tport_tpgt] = tv_tpg; > smp_mb__after_atomic_inc(); > match = true; > @@ -949,6 +1095,7 @@ static int vhost_scsi_clear_endpoint( > goto err_tpg; > } > tv_tpg->tv_tpg_vhost_count--; > + tv_tpg->vhost_scsi = NULL; > vs->vs_tpg[target] = NULL; > match = true; > mutex_unlock(&tv_tpg->tv_tpg_mutex); > @@ -969,6 +1116,7 @@ static int vhost_scsi_clear_endpoint( > vhost_scsi_flush(vs); > kfree(vs->vs_tpg); > vs->vs_tpg = NULL; > + WARN_ON(vs->vs_events_nr); > mutex_unlock(&vs->dev.mutex); > mutex_unlock(&tcm_vhost_mutex); > return 0; > @@ -1009,6 +1157,10 @@ static int vhost_scsi_open(struct inode *inode, struct file *f) > return -ENOMEM; > > vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work); > + vhost_work_init(&s->vs_event_work, tcm_vhost_evt_work); > + > + s->vs_events_nr = 0; > + s->vs_events_missed = false; > > s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick; > s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick; > @@ -1035,6 +1187,8 @@ static int vhost_scsi_release(struct inode *inode, struct file *f) > vhost_scsi_clear_endpoint(s, &t); > vhost_dev_stop(&s->dev); > vhost_dev_cleanup(&s->dev, false); > + /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */ > + vhost_scsi_flush(s); > kfree(s); > return 0; > } > @@ -1139,28 +1293,80 @@ static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport) > return "Unknown"; > } > > +static void tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg, > + struct se_lun *lun, bool plug) > +{ > + > + struct vhost_scsi *vs = tpg->vhost_scsi; > + struct vhost_virtqueue *vq; > + u32 reason; > + > + if (!vs) > + return; > + > + mutex_lock(&vs->dev.mutex); > + if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) { > + mutex_unlock(&vs->dev.mutex); > + return; > + } > + > + if (plug) > + reason = VIRTIO_SCSI_EVT_RESET_RESCAN; > + else > + reason = VIRTIO_SCSI_EVT_RESET_REMOVED; > + > + vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; > + mutex_lock(&vq->mutex); > + tcm_vhost_send_evt(vs, tpg, lun, > + VIRTIO_SCSI_T_TRANSPORT_RESET, reason); > + mutex_unlock(&vq->mutex); > + mutex_unlock(&vs->dev.mutex); > +} > + > +static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) > +{ > + tcm_vhost_do_plug(tpg, lun, true); > +} > + > +static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) > +{ > + tcm_vhost_do_plug(tpg, lun, false); > +} > + > static int tcm_vhost_port_link(struct se_portal_group *se_tpg, > struct se_lun *lun) > { > struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, > struct tcm_vhost_tpg, se_tpg); > > + mutex_lock(&tcm_vhost_mutex); > + > mutex_lock(&tv_tpg->tv_tpg_mutex); > tv_tpg->tv_tpg_port_count++; > mutex_unlock(&tv_tpg->tv_tpg_mutex); > > + tcm_vhost_hotplug(tv_tpg, lun); > + > + mutex_unlock(&tcm_vhost_mutex); > + > return 0; > } > > static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg, > - struct se_lun *se_lun) > + struct se_lun *lun) > { > struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, > struct tcm_vhost_tpg, se_tpg); > > + mutex_lock(&tcm_vhost_mutex); > + > mutex_lock(&tv_tpg->tv_tpg_mutex); > tv_tpg->tv_tpg_port_count--; > mutex_unlock(&tv_tpg->tv_tpg_mutex); > + > + tcm_vhost_hotunplug(tv_tpg, lun); > + > + mutex_unlock(&tcm_vhost_mutex); > } > > static struct se_node_acl *tcm_vhost_make_nodeacl( > diff --git a/drivers/vhost/tcm_vhost.h b/drivers/vhost/tcm_vhost.h > index 1d2ae7a..a545a5b 100644 > --- a/drivers/vhost/tcm_vhost.h > +++ b/drivers/vhost/tcm_vhost.h > @@ -53,6 +53,7 @@ struct tcm_vhost_nacl { > struct se_node_acl se_node_acl; > }; > > +struct vhost_scsi; > struct tcm_vhost_tpg { > /* Vhost port target portal group tag for TCM */ > u16 tport_tpgt; > @@ -70,6 +71,8 @@ struct tcm_vhost_tpg { > struct tcm_vhost_tport *tport; > /* Returned by tcm_vhost_make_tpg() */ > struct se_portal_group se_tpg; > + /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */ > + struct vhost_scsi *vhost_scsi; > }; > > struct tcm_vhost_tport { > @@ -83,6 +86,13 @@ struct tcm_vhost_tport { > struct se_wwn tport_wwn; > }; > > +struct tcm_vhost_evt { > + /* event to be sent to guest */ > + struct virtio_scsi_event event; > + /* event list, serviced from vhost worker thread */ > + struct llist_node list; > +}; > + > /* > * As per request from MST, keep TCM_VHOST related ioctl defines out of > * linux/vhost.h (user-space) for now.. > -- > 1.8.1.4
Michael S. Tsirkin
2013-Apr-25 07:40 UTC
[PATCH v11 3/4] tcm_vhost: Add ioctl to get and set events missed flag
On Thu, Apr 25, 2013 at 03:35:22PM +0800, Asias He wrote:> Signed-off-by: Asias He <asias at redhat.com>Acked-by: Michael S. Tsirkin <mst at redhat.com>> --- > drivers/vhost/tcm_vhost.c | 17 +++++++++++++++++ > drivers/vhost/tcm_vhost.h | 3 +++ > 2 files changed, 20 insertions(+) > > diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c > index 5340fd7..07217d8 100644 > --- a/drivers/vhost/tcm_vhost.c > +++ b/drivers/vhost/tcm_vhost.c > @@ -1200,8 +1200,11 @@ static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, > struct vhost_scsi_target backend; > void __user *argp = (void __user *)arg; > u64 __user *featurep = argp; > + u32 __user *eventsp = argp; > + u32 events_missed; > u64 features; > int r, abi_version = VHOST_SCSI_ABI_VERSION; > + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; > > switch (ioctl) { > case VHOST_SCSI_SET_ENDPOINT: > @@ -1222,6 +1225,20 @@ static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, > if (copy_to_user(argp, &abi_version, sizeof abi_version)) > return -EFAULT; > return 0; > + case VHOST_SCSI_SET_EVENTS_MISSED: > + if (get_user(events_missed, eventsp)) > + return -EFAULT; > + mutex_lock(&vq->mutex); > + vs->vs_events_missed = events_missed; > + mutex_unlock(&vq->mutex); > + return 0; > + case VHOST_SCSI_GET_EVENTS_MISSED: > + mutex_lock(&vq->mutex); > + events_missed = vs->vs_events_missed; > + mutex_unlock(&vq->mutex); > + if (put_user(events_missed, eventsp)) > + return -EFAULT; > + return 0; > case VHOST_GET_FEATURES: > features = VHOST_SCSI_FEATURES; > if (copy_to_user(featurep, &features, sizeof features)) > diff --git a/drivers/vhost/tcm_vhost.h b/drivers/vhost/tcm_vhost.h > index a545a5b..514b9fd 100644 > --- a/drivers/vhost/tcm_vhost.h > +++ b/drivers/vhost/tcm_vhost.h > @@ -123,3 +123,6 @@ struct vhost_scsi_target { > #define VHOST_SCSI_CLEAR_ENDPOINT _IOW(VHOST_VIRTIO, 0x41, struct vhost_scsi_target) > /* Changing this breaks userspace. */ > #define VHOST_SCSI_GET_ABI_VERSION _IOW(VHOST_VIRTIO, 0x42, int) > +/* Set and get the events missed flag */ > +#define VHOST_SCSI_SET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x43, __u32) > +#define VHOST_SCSI_GET_EVENTS_MISSED _IOW(VHOST_VIRTIO, 0x44, __u32) > -- > 1.8.1.4
On Thu, 2013-04-25 at 10:39 +0300, Michael S. Tsirkin wrote:> On Thu, Apr 25, 2013 at 03:35:19PM +0800, Asias He wrote: > > Changes in v11 > > - Drop change log histroy in commit log > > > > Changes in v10 > > - Drop comments about lun > > - Add Enable VIRTIO_SCSI_F_HOTPLUG to this series > > > > Changes in v9 > > - Drop tcm_vhost_check_feature > > - Add Refactor the lock nesting rule to this sereis > > > > Asias He (4): > > tcm_vhost: Refactor the lock nesting rule > > tcm_vhost: Add hotplug/hotunplug support > > tcm_vhost: Add ioctl to get and set events missed flag > > tcm_vhost: Enable VIRTIO_SCSI_F_HOTPLUG > > > > drivers/vhost/tcm_vhost.c | 262 +++++++++++++++++++++++++++++++++++++++++++--- > > drivers/vhost/tcm_vhost.h | 13 +++ > > 2 files changed, 259 insertions(+), 16 deletions(-) > > > Acked-by: Michael S. Tsirkin <mst at redhat.com> >Applied to target-pending/for-next. Nice work Asias & MST ! --nab