diff options
Diffstat (limited to 'drivers/vhost/scsi.c')
| -rw-r--r-- | drivers/vhost/scsi.c | 2046 |
1 files changed, 2046 insertions, 0 deletions
diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c new file mode 100644 index 000000000000..19ca021bf88c --- /dev/null +++ b/drivers/vhost/scsi.c @@ -0,0 +1,2046 @@ +/******************************************************************************* + * Vhost kernel TCM fabric driver for virtio SCSI initiators + * + * (C) Copyright 2010-2012 RisingTide Systems LLC. + * (C) Copyright 2010-2012 IBM Corp. + * + * Licensed to the Linux Foundation under the General Public License (GPL) version 2. + * + * Authors: Nicholas A. Bellinger <nab@risingtidesystems.com> + * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + ****************************************************************************/ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <generated/utsrelease.h> +#include <linux/utsname.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/kthread.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/configfs.h> +#include <linux/ctype.h> +#include <linux/compat.h> +#include <linux/eventfd.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <asm/unaligned.h> +#include <scsi/scsi.h> +#include <scsi/scsi_tcq.h> +#include <target/target_core_base.h> +#include <target/target_core_fabric.h> +#include <target/target_core_fabric_configfs.h> +#include <target/target_core_configfs.h> +#include <target/configfs_macros.h> +#include <linux/vhost.h> +#include <linux/virtio_scsi.h> +#include <linux/llist.h> +#include <linux/bitmap.h> + +#include "vhost.c" +#include "vhost.h" +#include "tcm_vhost.h" + +enum { + VHOST_SCSI_VQ_CTL = 0, + VHOST_SCSI_VQ_EVT = 1, + VHOST_SCSI_VQ_IO = 2, +}; + +/* + * VIRTIO_RING_F_EVENT_IDX seems broken. Not sure the bug is in + * kernel but disabling it helps. + * TODO: debug and remove the workaround. + */ +enum { + VHOST_SCSI_FEATURES = (VHOST_FEATURES & (~VIRTIO_RING_F_EVENT_IDX)) | + (1ULL << VIRTIO_SCSI_F_HOTPLUG) +}; + +#define VHOST_SCSI_MAX_TARGET 256 +#define VHOST_SCSI_MAX_VQ 128 +#define VHOST_SCSI_MAX_EVENT 128 + +struct vhost_scsi_inflight { + /* Wait for the flush operation to finish */ + struct completion comp; + /* Refcount for the inflight reqs */ + struct kref kref; +}; + +struct vhost_scsi_virtqueue { + struct vhost_virtqueue vq; + /* + * Reference counting for inflight reqs, used for flush operation. At + * each time, one reference tracks new commands submitted, while we + * wait for another one to reach 0. + */ + struct vhost_scsi_inflight inflights[2]; + /* + * Indicate current inflight in use, protected by vq->mutex. + * Writers must also take dev mutex and flush under it. + */ + int inflight_idx; +}; + +struct vhost_scsi { + /* Protected by vhost_scsi->dev.mutex */ + struct tcm_vhost_tpg **vs_tpg; + char vs_vhost_wwpn[TRANSPORT_IQN_LEN]; + + struct vhost_dev dev; + struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ]; + + 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 */ +static struct target_fabric_configfs *tcm_vhost_fabric_configfs; + +static struct workqueue_struct *tcm_vhost_workqueue; + +/* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */ +static DEFINE_MUTEX(tcm_vhost_mutex); +static LIST_HEAD(tcm_vhost_list); + +static int iov_num_pages(struct iovec *iov) +{ + return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) - + ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT; +} + +void tcm_vhost_done_inflight(struct kref *kref) +{ + struct vhost_scsi_inflight *inflight; + + inflight = container_of(kref, struct vhost_scsi_inflight, kref); + complete(&inflight->comp); +} + +static void tcm_vhost_init_inflight(struct vhost_scsi *vs, + struct vhost_scsi_inflight *old_inflight[]) +{ + struct vhost_scsi_inflight *new_inflight; + struct vhost_virtqueue *vq; + int idx, i; + + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) { + vq = &vs->vqs[i].vq; + + mutex_lock(&vq->mutex); + + /* store old infight */ + idx = vs->vqs[i].inflight_idx; + if (old_inflight) + old_inflight[i] = &vs->vqs[i].inflights[idx]; + + /* setup new infight */ + vs->vqs[i].inflight_idx = idx ^ 1; + new_inflight = &vs->vqs[i].inflights[idx ^ 1]; + kref_init(&new_inflight->kref); + init_completion(&new_inflight->comp); + + mutex_unlock(&vq->mutex); + } +} + +static struct vhost_scsi_inflight * +tcm_vhost_get_inflight(struct vhost_virtqueue *vq) +{ + struct vhost_scsi_inflight *inflight; + struct vhost_scsi_virtqueue *svq; + + svq = container_of(vq, struct vhost_scsi_virtqueue, vq); + inflight = &svq->inflights[svq->inflight_idx]; + kref_get(&inflight->kref); + + return inflight; +} + +static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight) +{ + kref_put(&inflight->kref, tcm_vhost_done_inflight); +} + +static int tcm_vhost_check_true(struct se_portal_group *se_tpg) +{ + return 1; +} + +static int tcm_vhost_check_false(struct se_portal_group *se_tpg) +{ + return 0; +} + +static char *tcm_vhost_get_fabric_name(void) +{ + return "vhost"; +} + +static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_get_fabric_proto_ident(se_tpg); + case SCSI_PROTOCOL_FCP: + return fc_get_fabric_proto_ident(se_tpg); + case SCSI_PROTOCOL_ISCSI: + return iscsi_get_fabric_proto_ident(se_tpg); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_get_fabric_proto_ident(se_tpg); +} + +static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + return &tport->tport_name[0]; +} + +static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + return tpg->tport_tpgt; +} + +static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg) +{ + return 1; +} + +static u32 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl, + struct t10_pr_registration *pr_reg, + int *format_code, + unsigned char *buf) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); + case SCSI_PROTOCOL_FCP: + return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); + case SCSI_PROTOCOL_ISCSI: + return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg, + format_code, buf); +} + +static u32 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl, + struct t10_pr_registration *pr_reg, + int *format_code) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); + case SCSI_PROTOCOL_FCP: + return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); + case SCSI_PROTOCOL_ISCSI: + return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg, + format_code); +} + +static char *tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg, + const char *buf, + u32 *out_tid_len, + char **port_nexus_ptr) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport = tpg->tport; + + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); + case SCSI_PROTOCOL_FCP: + return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); + case SCSI_PROTOCOL_ISCSI: + return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); + default: + pr_err("Unknown tport_proto_id: 0x%02x, using" + " SAS emulation\n", tport->tport_proto_id); + break; + } + + return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len, + port_nexus_ptr); +} + +static struct se_node_acl *tcm_vhost_alloc_fabric_acl( + struct se_portal_group *se_tpg) +{ + struct tcm_vhost_nacl *nacl; + + nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL); + if (!nacl) { + pr_err("Unable to allocate struct tcm_vhost_nacl\n"); + return NULL; + } + + return &nacl->se_node_acl; +} + +static void tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg, + struct se_node_acl *se_nacl) +{ + struct tcm_vhost_nacl *nacl = container_of(se_nacl, + struct tcm_vhost_nacl, se_node_acl); + kfree(nacl); +} + +static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg) +{ + return 1; +} + +static void tcm_vhost_release_cmd(struct se_cmd *se_cmd) +{ + return; +} + +static int tcm_vhost_shutdown_session(struct se_session *se_sess) +{ + return 0; +} + +static void tcm_vhost_close_session(struct se_session *se_sess) +{ + return; +} + +static u32 tcm_vhost_sess_get_index(struct se_session *se_sess) +{ + return 0; +} + +static int tcm_vhost_write_pending(struct se_cmd *se_cmd) +{ + /* Go ahead and process the write immediately */ + target_execute_cmd(se_cmd); + return 0; +} + +static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd) +{ + return 0; +} + +static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl) +{ + return; +} + +static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd) +{ + return 0; +} + +static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd) +{ + return 0; +} + +static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *tv_cmd) +{ + struct vhost_scsi *vs = tv_cmd->tvc_vhost; + + llist_add(&tv_cmd->tvc_completion_list, &vs->vs_completion_list); + + vhost_work_queue(&vs->dev, &vs->vs_completion_work); +} + +static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd) +{ + struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd, + struct tcm_vhost_cmd, tvc_se_cmd); + vhost_scsi_complete_cmd(tv_cmd); + return 0; +} + +static int tcm_vhost_queue_status(struct se_cmd *se_cmd) +{ + struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd, + struct tcm_vhost_cmd, tvc_se_cmd); + vhost_scsi_complete_cmd(tv_cmd); + return 0; +} + +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].vq; + 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; + + /* TODO locking against target/backend threads? */ + transport_generic_free_cmd(se_cmd, 1); + + if (tv_cmd->tvc_sgl_count) { + u32 i; + for (i = 0; i < tv_cmd->tvc_sgl_count; i++) + put_page(sg_page(&tv_cmd->tvc_sgl[i])); + + kfree(tv_cmd->tvc_sgl); + } + + tcm_vhost_put_inflight(tv_cmd->inflight); + + 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].vq; + 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].vq; + 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 + * process mm and can access the vring. + */ +static void vhost_scsi_complete_cmd_work(struct vhost_work *work) +{ + struct vhost_scsi *vs = container_of(work, struct vhost_scsi, + vs_completion_work); + DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ); + struct virtio_scsi_cmd_resp v_rsp; + struct tcm_vhost_cmd *tv_cmd; + struct llist_node *llnode; + struct se_cmd *se_cmd; + int ret, vq; + + bitmap_zero(signal, VHOST_SCSI_MAX_VQ); + llnode = llist_del_all(&vs->vs_completion_list); + while (llnode) { + tv_cmd = llist_entry(llnode, struct tcm_vhost_cmd, + tvc_completion_list); + llnode = llist_next(llnode); + se_cmd = &tv_cmd->tvc_se_cmd; + + pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__, + tv_cmd, se_cmd->residual_count, se_cmd->scsi_status); + + memset(&v_rsp, 0, sizeof(v_rsp)); + v_rsp.resid = se_cmd->residual_count; + /* TODO is status_qualifier field needed? */ + v_rsp.status = se_cmd->scsi_status; + v_rsp.sense_len = se_cmd->scsi_sense_length; + memcpy(v_rsp.sense, tv_cmd->tvc_sense_buf, + v_rsp.sense_len); + ret = copy_to_user(tv_cmd->tvc_resp, &v_rsp, sizeof(v_rsp)); + if (likely(ret == 0)) { + struct vhost_scsi_virtqueue *q; + vhost_add_used(tv_cmd->tvc_vq, tv_cmd->tvc_vq_desc, 0); + q = container_of(tv_cmd->tvc_vq, struct vhost_scsi_virtqueue, vq); + vq = q - vs->vqs; + __set_bit(vq, signal); + } else + pr_err("Faulted on virtio_scsi_cmd_resp\n"); + + vhost_scsi_free_cmd(tv_cmd); + } + + vq = -1; + while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1)) + < VHOST_SCSI_MAX_VQ) + vhost_signal(&vs->dev, &vs->vqs[vq].vq); +} + +static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd( + struct vhost_virtqueue *vq, + struct tcm_vhost_tpg *tv_tpg, + struct virtio_scsi_cmd_req *v_req, + u32 exp_data_len, + int data_direction) +{ + struct tcm_vhost_cmd *tv_cmd; + struct tcm_vhost_nexus *tv_nexus; + + tv_nexus = tv_tpg->tpg_nexus; + if (!tv_nexus) { + pr_err("Unable to locate active struct tcm_vhost_nexus\n"); + return ERR_PTR(-EIO); + } + + tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC); + if (!tv_cmd) { + pr_err("Unable to allocate struct tcm_vhost_cmd\n"); + return ERR_PTR(-ENOMEM); + } + tv_cmd->tvc_tag = v_req->tag; + tv_cmd->tvc_task_attr = v_req->task_attr; + tv_cmd->tvc_exp_data_len = exp_data_len; + tv_cmd->tvc_data_direction = data_direction; + tv_cmd->tvc_nexus = tv_nexus; + tv_cmd->inflight = tcm_vhost_get_inflight(vq); + + return tv_cmd; +} + +/* + * Map a user memory range into a scatterlist + * + * Returns the number of scatterlist entries used or -errno on error. + */ +static int vhost_scsi_map_to_sgl(struct scatterlist *sgl, + unsigned int sgl_count, struct iovec *iov, int write) +{ + unsigned int npages = 0, pages_nr, offset, nbytes; + struct scatterlist *sg = sgl; + void __user *ptr = iov->iov_base; + size_t len = iov->iov_len; + struct page **pages; + int ret, i; + + pages_nr = iov_num_pages(iov); + if (pages_nr > sgl_count) + return -ENOBUFS; + + pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL); + if (!pages) + return -ENOMEM; + + ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages); + /* No pages were pinned */ + if (ret < 0) + goto out; + /* Less pages pinned than wanted */ + if (ret != pages_nr) { + for (i = 0; i < ret; i++) + put_page(pages[i]); + ret = -EFAULT; + goto out; + } + + while (len > 0) { + offset = (uintptr_t)ptr & ~PAGE_MASK; + nbytes = min_t(unsigned int, PAGE_SIZE - offset, len); + sg_set_page(sg, pages[npages], nbytes, offset); + ptr += nbytes; + len -= nbytes; + sg++; + npages++; + } + +out: + kfree(pages); + return ret; +} + +static int vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd, + struct iovec *iov, unsigned int niov, int write) +{ + int ret; + unsigned int i; + u32 sgl_count; + struct scatterlist *sg; + + /* + * Find out how long sglist needs to be + */ + sgl_count = 0; + for (i = 0; i < niov; i++) + sgl_count += iov_num_pages(&iov[i]); + + /* TODO overflow checking */ + + sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC); + if (!sg) + return -ENOMEM; + pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__, + sg, sgl_count, !sg); + sg_init_table(sg, sgl_count); + + tv_cmd->tvc_sgl = sg; + tv_cmd->tvc_sgl_count = sgl_count; + + pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count); + for (i = 0; i < niov; i++) { + ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write); + if (ret < 0) { + for (i = 0; i < tv_cmd->tvc_sgl_count; i++) + put_page(sg_page(&tv_cmd->tvc_sgl[i])); + kfree(tv_cmd->tvc_sgl); + tv_cmd->tvc_sgl = NULL; + tv_cmd->tvc_sgl_count = 0; + return ret; + } + + sg += ret; + sgl_count -= ret; + } + return 0; +} + +static void tcm_vhost_submission_work(struct work_struct *work) +{ + struct tcm_vhost_cmd *tv_cmd = + container_of(work, struct tcm_vhost_cmd, work); + struct tcm_vhost_nexus *tv_nexus; + struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd; + struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL; + int rc, sg_no_bidi = 0; + + if (tv_cmd->tvc_sgl_count) { + sg_ptr = tv_cmd->tvc_sgl; +/* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */ +#if 0 + if (se_cmd->se_cmd_flags & SCF_BIDI) { + sg_bidi_ptr = NULL; + sg_no_bidi = 0; + } +#endif + } else { + sg_ptr = NULL; + } + tv_nexus = tv_cmd->tvc_nexus; + + rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess, + tv_cmd->tvc_cdb, &tv_cmd->tvc_sense_buf[0], + tv_cmd->tvc_lun, tv_cmd->tvc_exp_data_len, + tv_cmd->tvc_task_attr, tv_cmd->tvc_data_direction, + 0, sg_ptr, tv_cmd->tvc_sgl_count, + sg_bidi_ptr, sg_no_bidi); + if (rc < 0) { + transport_send_check_condition_and_sense(se_cmd, + TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); + transport_generic_free_cmd(se_cmd, 0); + } +} + +static void vhost_scsi_send_bad_target(struct vhost_scsi *vs, + struct vhost_virtqueue *vq, int head, unsigned out) +{ + struct virtio_scsi_cmd_resp __user *resp; + struct virtio_scsi_cmd_resp rsp; + int ret; + + memset(&rsp, 0, sizeof(rsp)); + rsp.response = VIRTIO_SCSI_S_BAD_TARGET; + resp = vq->iov[out].iov_base; + ret = __copy_to_user(resp, &rsp, sizeof(rsp)); + if (!ret) + vhost_add_used_and_signal(&vs->dev, vq, head, 0); + else + pr_err("Faulted on virtio_scsi_cmd_resp\n"); +} + +static void vhost_scsi_handle_vq(struct vhost_scsi *vs, + struct vhost_virtqueue *vq) +{ + struct tcm_vhost_tpg **vs_tpg; + struct virtio_scsi_cmd_req v_req; + struct tcm_vhost_tpg *tv_tpg; + struct tcm_vhost_cmd *tv_cmd; + u32 exp_data_len, data_first, data_num, data_direction; + unsigned out, in, i; + int head, ret; + u8 target; + + /* + * We can handle the vq only after the endpoint is setup by calling the + * VHOST_SCSI_SET_ENDPOINT ioctl. + * + * TODO: Check that we are running from vhost_worker which acts + * as read-side critical section for vhost kind of RCU. + * See the comments in struct vhost_virtqueue in drivers/vhost/vhost.h + */ + vs_tpg = rcu_dereference_check(vq->private_data, 1); + if (!vs_tpg) + return; + + mutex_lock(&vq->mutex); + vhost_disable_notify(&vs->dev, vq); + + for (;;) { + head = vhost_get_vq_desc(&vs->dev, vq, vq->iov, + ARRAY_SIZE(vq->iov), &out, &in, + NULL, NULL); + pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n", + head, out, in); + /* On error, stop handling until the next kick. */ + if (unlikely(head < 0)) + break; + /* Nothing new? Wait for eventfd to tell us they refilled. */ + if (head == vq->num) { + if (unlikely(vhost_enable_notify(&vs->dev, vq))) { + vhost_disable_notify(&vs->dev, vq); + continue; + } + break; + } + +/* FIXME: BIDI operation */ + if (out == 1 && in == 1) { + data_direction = DMA_NONE; + data_first = 0; + data_num = 0; + } else if (out == 1 && in > 1) { + data_direction = DMA_FROM_DEVICE; + data_first = out + 1; + data_num = in - 1; + } else if (out > 1 && in == 1) { + data_direction = DMA_TO_DEVICE; + data_first = 1; + data_num = out - 1; + } else { + vq_err(vq, "Invalid buffer layout out: %u in: %u\n", + out, in); + break; + } + + /* + * Check for a sane resp buffer so we can report errors to + * the guest. + */ + if (unlikely(vq->iov[out].iov_len != + sizeof(struct virtio_scsi_cmd_resp))) { + vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu" + " bytes\n", vq->iov[out].iov_len); + break; + } + + if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) { + vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu" + " bytes\n", vq->iov[0].iov_len); + break; + } + pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p," + " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req)); + ret = __copy_from_user(&v_req, vq->iov[0].iov_base, + sizeof(v_req)); + if (unlikely(ret)) { + vq_err(vq, "Faulted on virtio_scsi_cmd_req\n"); + break; + } + + /* Extract the tpgt */ + target = v_req.lun[1]; + tv_tpg = ACCESS_ONCE(vs_tpg[target]); + + /* Target does not exist, fail the request */ + if (unlikely(!tv_tpg)) { + vhost_scsi_send_bad_target(vs, vq, head, out); + continue; + } + + exp_data_len = 0; + for (i = 0; i < data_num; i++) + exp_data_len += vq->iov[data_first + i].iov_len; + + tv_cmd = vhost_scsi_allocate_cmd(vq, tv_tpg, &v_req, + exp_data_len, data_direction); + if (IS_ERR(tv_cmd)) { + vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n", + PTR_ERR(tv_cmd)); + goto err_cmd; + } + pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction" + ": %d\n", tv_cmd, exp_data_len, data_direction); + + tv_cmd->tvc_vhost = vs; + tv_cmd->tvc_vq = vq; + tv_cmd->tvc_resp = vq->iov[out].iov_base; + + /* + * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb + * that will be used by tcm_vhost_new_cmd_map() and down into + * target_setup_cmd_from_cdb() + */ + memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE); + /* + * Check that the recieved CDB size does not exceeded our + * hardcoded max for tcm_vhost + */ + /* TODO what if cdb was too small for varlen cdb header? */ + if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) > + TCM_VHOST_MAX_CDB_SIZE)) { + vq_err(vq, "Received SCSI CDB with command_size: %d that" + " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n", + scsi_command_size(tv_cmd->tvc_cdb), + TCM_VHOST_MAX_CDB_SIZE); + goto err_free; + } + tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF; + + pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n", + tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun); + + if (data_direction != DMA_NONE) { + ret = vhost_scsi_map_iov_to_sgl(tv_cmd, + &vq->iov[data_first], data_num, + data_direction == DMA_TO_DEVICE); + if (unlikely(ret)) { + vq_err(vq, "Failed to map iov to sgl\n"); + goto err_free; + } + } + + /* + * Save the descriptor from vhost_get_vq_desc() to be used to + * complete the virtio-scsi request in TCM callback context via + * tcm_vhost_queue_data_in() and tcm_vhost_queue_status() + */ + tv_cmd->tvc_vq_desc = head; + /* + * Dispatch tv_cmd descriptor for cmwq execution in process + * context provided by tcm_vhost_workqueue. This also ensures + * tv_cmd is executed on the same kworker CPU as this vhost + * thread to gain positive L2 cache locality effects.. + */ + INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work); + queue_work(tcm_vhost_workqueue, &tv_cmd->work); + } + + mutex_unlock(&vq->mutex); + return; + +err_free: + vhost_scsi_free_cmd(tv_cmd); +err_cmd: + vhost_scsi_send_bad_target(vs, vq, head, out); + mutex_unlock(&vq->mutex); +} + +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) +{ + 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) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev); + + vhost_scsi_handle_vq(vs, vq); +} + +static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index) +{ + vhost_poll_flush(&vs->vqs[index].vq.poll); +} + +/* Callers must hold dev mutex */ +static void vhost_scsi_flush(struct vhost_scsi *vs) +{ + struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ]; + int i; + + /* Init new inflight and remember the old inflight */ + tcm_vhost_init_inflight(vs, old_inflight); + + /* + * The inflight->kref was initialized to 1. We decrement it here to + * indicate the start of the flush operation so that it will reach 0 + * when all the reqs are finished. + */ + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) + kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight); + + /* Flush both the vhost poll and vhost work */ + 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); + + /* Wait for all reqs issued before the flush to be finished */ + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) + wait_for_completion(&old_inflight[i]->comp); +} + +/* + * 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, + struct vhost_scsi_target *t) +{ + struct tcm_vhost_tport *tv_tport; + struct tcm_vhost_tpg *tv_tpg; + struct tcm_vhost_tpg **vs_tpg; + struct vhost_virtqueue *vq; + 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].vq)) { + ret = -EFAULT; + goto out; + } + } + + len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET; + vs_tpg = kzalloc(len, GFP_KERNEL); + if (!vs_tpg) { + ret = -ENOMEM; + goto out; + } + if (vs->vs_tpg) + memcpy(vs_tpg, vs->vs_tpg, len); + + list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) { + mutex_lock(&tv_tpg->tv_tpg_mutex); + if (!tv_tpg->tpg_nexus) { + mutex_unlock(&tv_tpg->tv_tpg_mutex); + continue; + } + if (tv_tpg->tv_tpg_vhost_count != 0) { + mutex_unlock(&tv_tpg->tv_tpg_mutex); + continue; + } + tv_tport = tv_tpg->tport; + + if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) { + if (vs->vs_tpg && vs->vs_tpg[tv_tpg->tport_tpgt]) { + kfree(vs_tpg); + mutex_unlock(&tv_tpg->tv_tpg_mutex); + ret = -EEXIST; + 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; + } + mutex_unlock(&tv_tpg->tv_tpg_mutex); + } + + if (match) { + memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn, + sizeof(vs->vs_vhost_wwpn)); + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) { + vq = &vs->vqs[i].vq; + /* Flushing the vhost_work acts as synchronize_rcu */ + mutex_lock(&vq->mutex); + rcu_assign_pointer(vq->private_data, vs_tpg); + vhost_init_used(vq); + mutex_unlock(&vq->mutex); + } + ret = 0; + } else { + ret = -EEXIST; + } + + /* + * Act as synchronize_rcu to make sure access to + * old vs->vs_tpg is finished. + */ + vhost_scsi_flush(vs); + kfree(vs->vs_tpg); + vs->vs_tpg = vs_tpg; + +out: + mutex_unlock(&vs->dev.mutex); + mutex_unlock(&tcm_vhost_mutex); + return ret; +} + +static int vhost_scsi_clear_endpoint( + struct vhost_scsi *vs, + struct vhost_scsi_target *t) +{ + struct tcm_vhost_tport *tv_tport; + struct tcm_vhost_tpg *tv_tpg; + struct vhost_virtqueue *vq; + bool match = false; + 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) { + if (!vhost_vq_access_ok(&vs->vqs[index].vq)) { + ret = -EFAULT; + goto err_dev; + } + } + + if (!vs->vs_tpg) { + ret = 0; + goto err_dev; + } + + for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) { + target = i; + tv_tpg = vs->vs_tpg[target]; + if (!tv_tpg) + continue; + + mutex_lock(&tv_tpg->tv_tpg_mutex); + tv_tport = tv_tpg->tport; + if (!tv_tport) { + ret = -ENODEV; + goto err_tpg; + } + + if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) { + pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu" + " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n", + tv_tport->tport_name, tv_tpg->tport_tpgt, + t->vhost_wwpn, t->vhost_tpgt); + ret = -EINVAL; + 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); + } + if (match) { + for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) { + vq = &vs->vqs[i].vq; + /* Flushing the vhost_work acts as synchronize_rcu */ + mutex_lock(&vq->mutex); + rcu_assign_pointer(vq->private_data, NULL); + mutex_unlock(&vq->mutex); + } + } + /* + * Act as synchronize_rcu to make sure access to + * old vs->vs_tpg is finished. + */ + 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; + +err_tpg: + mutex_unlock(&tv_tpg->tv_tpg_mutex); +err_dev: + mutex_unlock(&vs->dev.mutex); + mutex_unlock(&tcm_vhost_mutex); + return ret; +} + +static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features) +{ + if (features & ~VHOST_SCSI_FEATURES) + return -EOPNOTSUPP; + + mutex_lock(&vs->dev.mutex); + if ((features & (1 << VHOST_F_LOG_ALL)) && + !vhost_log_access_ok(&vs->dev)) { + mutex_unlock(&vs->dev.mutex); + return -EFAULT; + } + vs->dev.acked_features = features; + smp_wmb(); + vhost_scsi_flush(vs); + mutex_unlock(&vs->dev.mutex); + return 0; +} + +static int vhost_scsi_open(struct inode *inode, struct file *f) +{ + struct vhost_scsi *s; + struct vhost_virtqueue **vqs; + int r, i; + + s = kzalloc(sizeof(*s), GFP_KERNEL); + if (!s) + return -ENOMEM; + + vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL); + if (!vqs) { + kfree(s); + 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; + + vqs[VHOST_SCSI_VQ_CTL] = &s->vqs[VHOST_SCSI_VQ_CTL].vq; + vqs[VHOST_SCSI_VQ_EVT] = &s->vqs[VHOST_SCSI_VQ_EVT].vq; + s->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick; + s->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick; + for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) { + vqs[i] = &s->vqs[i].vq; + s->vqs[i].vq.handle_kick = vhost_scsi_handle_kick; + } + r = vhost_dev_init(&s->dev, vqs, VHOST_SCSI_MAX_VQ); + + tcm_vhost_init_inflight(s, NULL); + + if (r < 0) { + kfree(vqs); + kfree(s); + return r; + } + + f->private_data = s; + return 0; +} + +static int vhost_scsi_release(struct inode *inode, struct file *f) +{ + struct vhost_scsi *s = f->private_data; + struct vhost_scsi_target t; + + mutex_lock(&s->dev.mutex); + memcpy(t.vhost_wwpn, s->vs_vhost_wwpn, sizeof(t.vhost_wwpn)); + mutex_unlock(&s->dev.mutex); + 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->dev.vqs); + kfree(s); + return 0; +} + +static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + struct vhost_scsi *vs = f->private_data; + 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].vq; + + switch (ioctl) { + case VHOST_SCSI_SET_ENDPOINT: + if (copy_from_user(&backend, argp, sizeof backend)) + return -EFAULT; + if (backend.reserved != 0) + return -EOPNOTSUPP; + + return vhost_scsi_set_endpoint(vs, &backend); + case VHOST_SCSI_CLEAR_ENDPOINT: + if (copy_from_user(&backend, argp, sizeof backend)) + return -EFAULT; + if (backend.reserved != 0) + return -EOPNOTSUPP; + + return vhost_scsi_clear_endpoint(vs, &backend); + case VHOST_SCSI_GET_ABI_VERSION: + 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)) + return -EFAULT; + return 0; + case VHOST_SET_FEATURES: + if (copy_from_user(&features, featurep, sizeof features)) + return -EFAULT; + return vhost_scsi_set_features(vs, features); + default: + mutex_lock(&vs->dev.mutex); + r = vhost_dev_ioctl(&vs->dev, ioctl, argp); + /* TODO: flush backend after dev ioctl. */ + if (r == -ENOIOCTLCMD) + r = vhost_vring_ioctl(&vs->dev, ioctl, argp); + mutex_unlock(&vs->dev.mutex); + return r; + } +} + +#ifdef CONFIG_COMPAT +static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg)); +} +#endif + +static const struct file_operations vhost_scsi_fops = { + .owner = THIS_MODULE, + .release = vhost_scsi_release, + .unlocked_ioctl = vhost_scsi_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vhost_scsi_compat_ioctl, +#endif + .open = vhost_scsi_open, + .llseek = noop_llseek, +}; + +static struct miscdevice vhost_scsi_misc = { + MISC_DYNAMIC_MINOR, + "vhost-scsi", + &vhost_scsi_fops, +}; + +static int __init vhost_scsi_register(void) +{ + return misc_register(&vhost_scsi_misc); +} + +static int vhost_scsi_deregister(void) +{ + return misc_deregister(&vhost_scsi_misc); +} + +static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport) +{ + switch (tport->tport_proto_id) { + case SCSI_PROTOCOL_SAS: + return "SAS"; + case SCSI_PROTOCOL_FCP: + return "FCP"; + case SCSI_PROTOCOL_ISCSI: + return "iSCSI"; + default: + break; + } + + 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].vq; + 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 *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( + struct se_portal_group *se_tpg, + struct config_group *group, + const char *name) +{ + struct se_node_acl *se_nacl, *se_nacl_new; + struct tcm_vhost_nacl *nacl; + u64 wwpn = 0; + u32 nexus_depth; + + /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0) + return ERR_PTR(-EINVAL); */ + se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg); + if (!se_nacl_new) + return ERR_PTR(-ENOMEM); + + nexus_depth = 1; + /* + * se_nacl_new may be released by core_tpg_add_initiator_node_acl() + * when converting a NodeACL from demo mode -> explict + */ + se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new, + name, nexus_depth); + if (IS_ERR(se_nacl)) { + tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new); + return se_nacl; + } + /* + * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN + */ + nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl); + nacl->iport_wwpn = wwpn; + + return se_nacl; +} + +static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl) +{ + struct tcm_vhost_nacl *nacl = container_of(se_acl, + struct tcm_vhost_nacl, se_node_acl); + core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1); + kfree(nacl); +} + +static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg, + const char *name) +{ + struct se_portal_group *se_tpg; + struct tcm_vhost_nexus *tv_nexus; + + mutex_lock(&tv_tpg->tv_tpg_mutex); + if (tv_tpg->tpg_nexus) { + mutex_unlock(&tv_tpg->tv_tpg_mutex); + pr_debug("tv_tpg->tpg_nexus already exists\n"); + return -EEXIST; + } + se_tpg = &tv_tpg->se_tpg; + + tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL); + if (!tv_nexus) { + mutex_unlock(&tv_tpg->tv_tpg_mutex); + pr_err("Unable to allocate struct tcm_vhost_nexus\n"); + return -ENOMEM; + } + /* + * Initialize the struct se_session pointer + */ + tv_nexus->tvn_se_sess = transport_init_session(); + if (IS_ERR(tv_nexus->tvn_se_sess)) { + mutex_unlock(&tv_tpg->tv_tpg_mutex); + kfree(tv_nexus); + return -ENOMEM; + } + /* + * Since we are running in 'demo mode' this call with generate a + * struct se_node_acl for the tcm_vhost struct se_portal_group with + * the SCSI Initiator port name of the passed configfs group 'name'. + */ + tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl( + se_tpg, (unsigned char *)name); + if (!tv_nexus->tvn_se_sess->se_node_acl) { + mutex_unlock(&tv_tpg->tv_tpg_mutex); + pr_debug("core_tpg_check_initiator_node_acl() failed" + " for %s\n", name); + transport_free_session(tv_nexus->tvn_se_sess); + kfree(tv_nexus); + return -ENOMEM; + } + /* + * Now register the TCM vhost virtual I_T Nexus as active with the + * call to __transport_register_session() + */ + __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl, + tv_nexus->tvn_se_sess, tv_nexus); + tv_tpg->tpg_nexus = tv_nexus; + + mutex_unlock(&tv_tpg->tv_tpg_mutex); + return 0; +} + +static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg) +{ + struct se_session *se_sess; + struct tcm_vhost_nexus *tv_nexus; + + mutex_lock(&tpg->tv_tpg_mutex); + tv_nexus = tpg->tpg_nexus; + if (!tv_nexus) { + mutex_unlock(&tpg->tv_tpg_mutex); + return -ENODEV; + } + + se_sess = tv_nexus->tvn_se_sess; + if (!se_sess) { + mutex_unlock(&tpg->tv_tpg_mutex); + return -ENODEV; + } + + if (tpg->tv_tpg_port_count != 0) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_err("Unable to remove TCM_vhost I_T Nexus with" + " active TPG port count: %d\n", + tpg->tv_tpg_port_count); + return -EBUSY; + } + + if (tpg->tv_tpg_vhost_count != 0) { + mutex_unlock(&tpg->tv_tpg_mutex); + pr_err("Unable to remove TCM_vhost I_T Nexus with" + " active TPG vhost count: %d\n", + tpg->tv_tpg_vhost_count); + return -EBUSY; + } + + pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated" + " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport), + tv_nexus->tvn_se_sess->se_node_acl->initiatorname); + /* + * Release the SCSI I_T Nexus to the emulated vhost Target Port + */ + transport_deregister_session(tv_nexus->tvn_se_sess); + tpg->tpg_nexus = NULL; + mutex_unlock(&tpg->tv_tpg_mutex); + + kfree(tv_nexus); + return 0; +} + +static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg, + char *page) +{ + struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_nexus *tv_nexus; + ssize_t ret; + + mutex_lock(&tv_tpg->tv_tpg_mutex); + tv_nexus = tv_tpg->tpg_nexus; + if (!tv_nexus) { + mutex_unlock(&tv_tpg->tv_tpg_mutex); + return -ENODEV; + } + ret = snprintf(page, PAGE_SIZE, "%s\n", + tv_nexus->tvn_se_sess->se_node_acl->initiatorname); + mutex_unlock(&tv_tpg->tv_tpg_mutex); + + return ret; +} + +static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg, + const char *page, + size_t count) +{ + struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + struct tcm_vhost_tport *tport_wwn = tv_tpg->tport; + unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr; + int ret; + /* + * Shutdown the active I_T nexus if 'NULL' is passed.. + */ + if (!strncmp(page, "NULL", 4)) { + ret = tcm_vhost_drop_nexus(tv_tpg); + return (!ret) ? count : ret; + } + /* + * Otherwise make sure the passed virtual Initiator port WWN matches + * the fabric protocol_id set in tcm_vhost_make_tport(), and call + * tcm_vhost_make_nexus(). + */ + if (strlen(page) >= TCM_VHOST_NAMELEN) { + pr_err("Emulated NAA Sas Address: %s, exceeds" + " max: %d\n", page, TCM_VHOST_NAMELEN); + return -EINVAL; + } + snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page); + + ptr = strstr(i_port, "naa."); + if (ptr) { + if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) { + pr_err("Passed SAS Initiator Port %s does not" + " match target port protoid: %s\n", i_port, + tcm_vhost_dump_proto_id(tport_wwn)); + return -EINVAL; + } + port_ptr = &i_port[0]; + goto check_newline; + } + ptr = strstr(i_port, "fc."); + if (ptr) { + if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) { + pr_err("Passed FCP Initiator Port %s does not" + " match target port protoid: %s\n", i_port, + tcm_vhost_dump_proto_id(tport_wwn)); + return -EINVAL; + } + port_ptr = &i_port[3]; /* Skip over "fc." */ + goto check_newline; + } + ptr = strstr(i_port, "iqn."); + if (ptr) { + if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) { + pr_err("Passed iSCSI Initiator Port %s does not" + " match target port protoid: %s\n", i_port, + tcm_vhost_dump_proto_id(tport_wwn)); + return -EINVAL; + } + port_ptr = &i_port[0]; + goto check_newline; + } + pr_err("Unable to locate prefix for emulated Initiator Port:" + " %s\n", i_port); + return -EINVAL; + /* + * Clear any trailing newline for the NAA WWN + */ +check_newline: + if (i_port[strlen(i_port)-1] == '\n') + i_port[strlen(i_port)-1] = '\0'; + + ret = tcm_vhost_make_nexus(tv_tpg, port_ptr); + if (ret < 0) + return ret; + + return count; +} + +TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR); + +static struct configfs_attribute *tcm_vhost_tpg_attrs[] = { + &tcm_vhost_tpg_nexus.attr, + NULL, +}; + +static struct se_portal_group *tcm_vhost_make_tpg(struct se_wwn *wwn, + struct config_group *group, + const char *name) +{ + struct tcm_vhost_tport *tport = container_of(wwn, + struct tcm_vhost_tport, tport_wwn); + + struct tcm_vhost_tpg *tpg; + unsigned long tpgt; + int ret; + + if (strstr(name, "tpgt_") != name) + return ERR_PTR(-EINVAL); + if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX) + return ERR_PTR(-EINVAL); + + tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL); + if (!tpg) { + pr_err("Unable to allocate struct tcm_vhost_tpg"); + return ERR_PTR(-ENOMEM); + } + mutex_init(&tpg->tv_tpg_mutex); + INIT_LIST_HEAD(&tpg->tv_tpg_list); + tpg->tport = tport; + tpg->tport_tpgt = tpgt; + + ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn, + &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL); + if (ret < 0) { + kfree(tpg); + return NULL; + } + mutex_lock(&tcm_vhost_mutex); + list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list); + mutex_unlock(&tcm_vhost_mutex); + + return &tpg->se_tpg; +} + +static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg) +{ + struct tcm_vhost_tpg *tpg = container_of(se_tpg, + struct tcm_vhost_tpg, se_tpg); + + mutex_lock(&tcm_vhost_mutex); + list_del(&tpg->tv_tpg_list); + mutex_unlock(&tcm_vhost_mutex); + /* + * Release the virtual I_T Nexus for this vhost TPG + */ + tcm_vhost_drop_nexus(tpg); + /* + * Deregister the se_tpg from TCM.. + */ + core_tpg_deregister(se_tpg); + kfree(tpg); +} + +static struct se_wwn *tcm_vhost_make_tport(struct target_fabric_configfs *tf, + struct config_group *group, + const char *name) +{ + struct tcm_vhost_tport *tport; + char *ptr; + u64 wwpn = 0; + int off = 0; + + /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0) + return ERR_PTR(-EINVAL); */ + + tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL); + if (!tport) { + pr_err("Unable to allocate struct tcm_vhost_tport"); + return ERR_PTR(-ENOMEM); + } + tport->tport_wwpn = wwpn; + /* + * Determine the emulated Protocol Identifier and Target Port Name + * based on the incoming configfs directory name. + */ + ptr = strstr(name, "naa."); + if (ptr) { + tport->tport_proto_id = SCSI_PROTOCOL_SAS; + goto check_len; + } + ptr = strstr(name, "fc."); + if (ptr) { + tport->tport_proto_id = SCSI_PROTOCOL_FCP; + off = 3; /* Skip over "fc." */ + goto check_len; + } + ptr = strstr(name, "iqn."); + if (ptr) { + tport->tport_proto_id = SCSI_PROTOCOL_ISCSI; + goto check_len; + } + + pr_err("Unable to locate prefix for emulated Target Port:" + " %s\n", name); + kfree(tport); + return ERR_PTR(-EINVAL); + +check_len: + if (strlen(name) >= TCM_VHOST_NAMELEN) { + pr_err("Emulated %s Address: %s, exceeds" + " max: %d\n", name, tcm_vhost_dump_proto_id(tport), + TCM_VHOST_NAMELEN); + kfree(tport); + return ERR_PTR(-EINVAL); + } + snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]); + + pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target" + " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name); + + return &tport->tport_wwn; +} + +static void tcm_vhost_drop_tport(struct se_wwn *wwn) +{ + struct tcm_vhost_tport *tport = container_of(wwn, + struct tcm_vhost_tport, tport_wwn); + + pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target" + " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), + tport->tport_name); + + kfree(tport); +} + +static ssize_t tcm_vhost_wwn_show_attr_version( + struct target_fabric_configfs *tf, + char *page) +{ + return sprintf(page, "TCM_VHOST fabric module %s on %s/%s" + "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname, + utsname()->machine); +} + +TF_WWN_ATTR_RO(tcm_vhost, version); + +static struct configfs_attribute *tcm_vhost_wwn_attrs[] = { + &tcm_vhost_wwn_version.attr, + NULL, +}; + +static struct target_core_fabric_ops tcm_vhost_ops = { + .get_fabric_name = tcm_vhost_get_fabric_name, + .get_fabric_proto_ident = tcm_vhost_get_fabric_proto_ident, + .tpg_get_wwn = tcm_vhost_get_fabric_wwn, + .tpg_get_tag = tcm_vhost_get_tag, + .tpg_get_default_depth = tcm_vhost_get_default_depth, + .tpg_get_pr_transport_id = tcm_vhost_get_pr_transport_id, + .tpg_get_pr_transport_id_len = tcm_vhost_get_pr_transport_id_len, + .tpg_parse_pr_out_transport_id = tcm_vhost_parse_pr_out_transport_id, + .tpg_check_demo_mode = tcm_vhost_check_true, + .tpg_check_demo_mode_cache = tcm_vhost_check_true, + .tpg_check_demo_mode_write_protect = tcm_vhost_check_false, + .tpg_check_prod_mode_write_protect = tcm_vhost_check_false, + .tpg_alloc_fabric_acl = tcm_vhost_alloc_fabric_acl, + .tpg_release_fabric_acl = tcm_vhost_release_fabric_acl, + .tpg_get_inst_index = tcm_vhost_tpg_get_inst_index, + .release_cmd = tcm_vhost_release_cmd, + .shutdown_session = tcm_vhost_shutdown_session, + .close_session = tcm_vhost_close_session, + .sess_get_index = tcm_vhost_sess_get_index, + .sess_get_initiator_sid = NULL, + .write_pending = tcm_vhost_write_pending, + .write_pending_status = tcm_vhost_write_pending_status, + .set_default_node_attributes = tcm_vhost_set_default_node_attrs, + .get_task_tag = tcm_vhost_get_task_tag, + .get_cmd_state = tcm_vhost_get_cmd_state, + .queue_data_in = tcm_vhost_queue_data_in, + .queue_status = tcm_vhost_queue_status, + .queue_tm_rsp = tcm_vhost_queue_tm_rsp, + /* + * Setup callers for generic logic in target_core_fabric_configfs.c + */ + .fabric_make_wwn = tcm_vhost_make_tport, + .fabric_drop_wwn = tcm_vhost_drop_tport, + .fabric_make_tpg = tcm_vhost_make_tpg, + .fabric_drop_tpg = tcm_vhost_drop_tpg, + .fabric_post_link = tcm_vhost_port_link, + .fabric_pre_unlink = tcm_vhost_port_unlink, + .fabric_make_np = NULL, + .fabric_drop_np = NULL, + .fabric_make_nodeacl = tcm_vhost_make_nodeacl, + .fabric_drop_nodeacl = tcm_vhost_drop_nodeacl, +}; + +static int tcm_vhost_register_configfs(void) +{ + struct target_fabric_configfs *fabric; + int ret; + + pr_debug("TCM_VHOST fabric module %s on %s/%s" + " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname, + utsname()->machine); + /* + * Register the top level struct config_item_type with TCM core + */ + fabric = target_fabric_configfs_init(THIS_MODULE, "vhost"); + if (IS_ERR(fabric)) { + pr_err("target_fabric_configfs_init() failed\n"); + return PTR_ERR(fabric); + } + /* + * Setup fabric->tf_ops from our local tcm_vhost_ops + */ + fabric->tf_ops = tcm_vhost_ops; + /* + * Setup default attribute lists for various fabric->tf_cit_tmpl + */ + TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs; + TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs; + TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL; + TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL; + TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL; + TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL; + TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL; + TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL; + TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL; + /* + * Register the fabric for use within TCM + */ + ret = target_fabric_configfs_register(fabric); + if (ret < 0) { + pr_err("target_fabric_configfs_register() failed" + " for TCM_VHOST\n"); + return ret; + } + /* + * Setup our local pointer to *fabric + */ + tcm_vhost_fabric_configfs = fabric; + pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n"); + return 0; +}; + +static void tcm_vhost_deregister_configfs(void) +{ + if (!tcm_vhost_fabric_configfs) + return; + + target_fabric_configfs_deregister(tcm_vhost_fabric_configfs); + tcm_vhost_fabric_configfs = NULL; + pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n"); +}; + +static int __init tcm_vhost_init(void) +{ + int ret = -ENOMEM; + /* + * Use our own dedicated workqueue for submitting I/O into + * target core to avoid contention within system_wq. + */ + tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0); + if (!tcm_vhost_workqueue) + goto out; + + ret = vhost_scsi_register(); + if (ret < 0) + goto out_destroy_workqueue; + + ret = tcm_vhost_register_configfs(); + if (ret < 0) + goto out_vhost_scsi_deregister; + + return 0; + +out_vhost_scsi_deregister: + vhost_scsi_deregister(); +out_destroy_workqueue: + destroy_workqueue(tcm_vhost_workqueue); +out: + return ret; +}; + +static void tcm_vhost_exit(void) +{ + tcm_vhost_deregister_configfs(); + vhost_scsi_deregister(); + destroy_workqueue(tcm_vhost_workqueue); +}; + +MODULE_DESCRIPTION("TCM_VHOST series fabric driver"); +MODULE_LICENSE("GPL"); +module_init(tcm_vhost_init); +module_exit(tcm_vhost_exit); |