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- // SPDX-License-Identifier: GPL-2.0-or-later
- /*
- * Virtio SCSI HBA driver
- *
- * Copyright IBM Corp. 2010
- * Copyright Red Hat, Inc. 2011
- *
- * Authors:
- * Stefan Hajnoczi <[email protected]>
- * Paolo Bonzini <[email protected]>
- */
- #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
- #include <linux/module.h>
- #include <linux/slab.h>
- #include <linux/mempool.h>
- #include <linux/interrupt.h>
- #include <linux/virtio.h>
- #include <linux/virtio_ids.h>
- #include <linux/virtio_config.h>
- #include <linux/virtio_scsi.h>
- #include <linux/cpu.h>
- #include <linux/blkdev.h>
- #include <linux/blk-integrity.h>
- #include <scsi/scsi_host.h>
- #include <scsi/scsi_device.h>
- #include <scsi/scsi_cmnd.h>
- #include <scsi/scsi_tcq.h>
- #include <scsi/scsi_devinfo.h>
- #include <linux/seqlock.h>
- #include <linux/blk-mq-virtio.h>
- #include "sd.h"
- #define VIRTIO_SCSI_MEMPOOL_SZ 64
- #define VIRTIO_SCSI_EVENT_LEN 8
- #define VIRTIO_SCSI_VQ_BASE 2
- /* Command queue element */
- struct virtio_scsi_cmd {
- struct scsi_cmnd *sc;
- struct completion *comp;
- union {
- struct virtio_scsi_cmd_req cmd;
- struct virtio_scsi_cmd_req_pi cmd_pi;
- struct virtio_scsi_ctrl_tmf_req tmf;
- struct virtio_scsi_ctrl_an_req an;
- } req;
- union {
- struct virtio_scsi_cmd_resp cmd;
- struct virtio_scsi_ctrl_tmf_resp tmf;
- struct virtio_scsi_ctrl_an_resp an;
- struct virtio_scsi_event evt;
- } resp;
- } ____cacheline_aligned_in_smp;
- struct virtio_scsi_event_node {
- struct virtio_scsi *vscsi;
- struct virtio_scsi_event event;
- struct work_struct work;
- };
- struct virtio_scsi_vq {
- /* Protects vq */
- spinlock_t vq_lock;
- struct virtqueue *vq;
- };
- /* Driver instance state */
- struct virtio_scsi {
- struct virtio_device *vdev;
- /* Get some buffers ready for event vq */
- struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
- u32 num_queues;
- struct hlist_node node;
- /* Protected by event_vq lock */
- bool stop_events;
- struct virtio_scsi_vq ctrl_vq;
- struct virtio_scsi_vq event_vq;
- struct virtio_scsi_vq req_vqs[];
- };
- static struct kmem_cache *virtscsi_cmd_cache;
- static mempool_t *virtscsi_cmd_pool;
- static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev)
- {
- return vdev->priv;
- }
- static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
- {
- if (resid)
- scsi_set_resid(sc, min(resid, scsi_bufflen(sc)));
- }
- /*
- * virtscsi_complete_cmd - finish a scsi_cmd and invoke scsi_done
- *
- * Called with vq_lock held.
- */
- static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf)
- {
- struct virtio_scsi_cmd *cmd = buf;
- struct scsi_cmnd *sc = cmd->sc;
- struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd;
- dev_dbg(&sc->device->sdev_gendev,
- "cmd %p response %u status %#02x sense_len %u\n",
- sc, resp->response, resp->status, resp->sense_len);
- sc->result = resp->status;
- virtscsi_compute_resid(sc, virtio32_to_cpu(vscsi->vdev, resp->resid));
- switch (resp->response) {
- case VIRTIO_SCSI_S_OK:
- set_host_byte(sc, DID_OK);
- break;
- case VIRTIO_SCSI_S_OVERRUN:
- set_host_byte(sc, DID_ERROR);
- break;
- case VIRTIO_SCSI_S_ABORTED:
- set_host_byte(sc, DID_ABORT);
- break;
- case VIRTIO_SCSI_S_BAD_TARGET:
- set_host_byte(sc, DID_BAD_TARGET);
- break;
- case VIRTIO_SCSI_S_RESET:
- set_host_byte(sc, DID_RESET);
- break;
- case VIRTIO_SCSI_S_BUSY:
- set_host_byte(sc, DID_BUS_BUSY);
- break;
- case VIRTIO_SCSI_S_TRANSPORT_FAILURE:
- set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
- break;
- case VIRTIO_SCSI_S_TARGET_FAILURE:
- set_host_byte(sc, DID_BAD_TARGET);
- break;
- case VIRTIO_SCSI_S_NEXUS_FAILURE:
- set_status_byte(sc, SAM_STAT_RESERVATION_CONFLICT);
- break;
- default:
- scmd_printk(KERN_WARNING, sc, "Unknown response %d",
- resp->response);
- fallthrough;
- case VIRTIO_SCSI_S_FAILURE:
- set_host_byte(sc, DID_ERROR);
- break;
- }
- WARN_ON(virtio32_to_cpu(vscsi->vdev, resp->sense_len) >
- VIRTIO_SCSI_SENSE_SIZE);
- if (resp->sense_len) {
- memcpy(sc->sense_buffer, resp->sense,
- min_t(u32,
- virtio32_to_cpu(vscsi->vdev, resp->sense_len),
- VIRTIO_SCSI_SENSE_SIZE));
- }
- scsi_done(sc);
- }
- static void virtscsi_vq_done(struct virtio_scsi *vscsi,
- struct virtio_scsi_vq *virtscsi_vq,
- void (*fn)(struct virtio_scsi *vscsi, void *buf))
- {
- void *buf;
- unsigned int len;
- unsigned long flags;
- struct virtqueue *vq = virtscsi_vq->vq;
- spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
- do {
- virtqueue_disable_cb(vq);
- while ((buf = virtqueue_get_buf(vq, &len)) != NULL)
- fn(vscsi, buf);
- if (unlikely(virtqueue_is_broken(vq)))
- break;
- } while (!virtqueue_enable_cb(vq));
- spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
- }
- static void virtscsi_req_done(struct virtqueue *vq)
- {
- struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
- struct virtio_scsi *vscsi = shost_priv(sh);
- int index = vq->index - VIRTIO_SCSI_VQ_BASE;
- struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index];
- virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd);
- };
- static void virtscsi_poll_requests(struct virtio_scsi *vscsi)
- {
- int i, num_vqs;
- num_vqs = vscsi->num_queues;
- for (i = 0; i < num_vqs; i++)
- virtscsi_vq_done(vscsi, &vscsi->req_vqs[i],
- virtscsi_complete_cmd);
- }
- static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf)
- {
- struct virtio_scsi_cmd *cmd = buf;
- if (cmd->comp)
- complete(cmd->comp);
- }
- static void virtscsi_ctrl_done(struct virtqueue *vq)
- {
- struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
- struct virtio_scsi *vscsi = shost_priv(sh);
- virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
- };
- static void virtscsi_handle_event(struct work_struct *work);
- static int virtscsi_kick_event(struct virtio_scsi *vscsi,
- struct virtio_scsi_event_node *event_node)
- {
- int err;
- struct scatterlist sg;
- unsigned long flags;
- INIT_WORK(&event_node->work, virtscsi_handle_event);
- sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
- spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
- err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node,
- GFP_ATOMIC);
- if (!err)
- virtqueue_kick(vscsi->event_vq.vq);
- spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
- return err;
- }
- static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
- {
- int i;
- for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
- vscsi->event_list[i].vscsi = vscsi;
- virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
- }
- return 0;
- }
- static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
- {
- int i;
- /* Stop scheduling work before calling cancel_work_sync. */
- spin_lock_irq(&vscsi->event_vq.vq_lock);
- vscsi->stop_events = true;
- spin_unlock_irq(&vscsi->event_vq.vq_lock);
- for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++)
- cancel_work_sync(&vscsi->event_list[i].work);
- }
- static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
- struct virtio_scsi_event *event)
- {
- struct scsi_device *sdev;
- struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
- unsigned int target = event->lun[1];
- unsigned int lun = (event->lun[2] << 8) | event->lun[3];
- switch (virtio32_to_cpu(vscsi->vdev, event->reason)) {
- case VIRTIO_SCSI_EVT_RESET_RESCAN:
- if (lun == 0) {
- scsi_scan_target(&shost->shost_gendev, 0, target,
- SCAN_WILD_CARD, SCSI_SCAN_INITIAL);
- } else {
- scsi_add_device(shost, 0, target, lun);
- }
- break;
- case VIRTIO_SCSI_EVT_RESET_REMOVED:
- sdev = scsi_device_lookup(shost, 0, target, lun);
- if (sdev) {
- scsi_remove_device(sdev);
- scsi_device_put(sdev);
- } else {
- pr_err("SCSI device %d 0 %d %d not found\n",
- shost->host_no, target, lun);
- }
- break;
- default:
- pr_info("Unsupported virtio scsi event reason %x\n", event->reason);
- }
- }
- static void virtscsi_handle_param_change(struct virtio_scsi *vscsi,
- struct virtio_scsi_event *event)
- {
- struct scsi_device *sdev;
- struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
- unsigned int target = event->lun[1];
- unsigned int lun = (event->lun[2] << 8) | event->lun[3];
- u8 asc = virtio32_to_cpu(vscsi->vdev, event->reason) & 255;
- u8 ascq = virtio32_to_cpu(vscsi->vdev, event->reason) >> 8;
- sdev = scsi_device_lookup(shost, 0, target, lun);
- if (!sdev) {
- pr_err("SCSI device %d 0 %d %d not found\n",
- shost->host_no, target, lun);
- return;
- }
- /* Handle "Parameters changed", "Mode parameters changed", and
- "Capacity data has changed". */
- if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09))
- scsi_rescan_device(sdev);
- scsi_device_put(sdev);
- }
- static void virtscsi_rescan_hotunplug(struct virtio_scsi *vscsi)
- {
- struct scsi_device *sdev;
- struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
- unsigned char scsi_cmd[MAX_COMMAND_SIZE];
- int result, inquiry_len, inq_result_len = 256;
- char *inq_result = kmalloc(inq_result_len, GFP_KERNEL);
- shost_for_each_device(sdev, shost) {
- inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
- memset(scsi_cmd, 0, sizeof(scsi_cmd));
- scsi_cmd[0] = INQUIRY;
- scsi_cmd[4] = (unsigned char) inquiry_len;
- memset(inq_result, 0, inq_result_len);
- result = scsi_execute_cmd(sdev, scsi_cmd, REQ_OP_DRV_IN,
- inq_result, inquiry_len,
- SD_TIMEOUT, SD_MAX_RETRIES, NULL);
- if (result == 0 && inq_result[0] >> 5) {
- /* PQ indicates the LUN is not attached */
- scsi_remove_device(sdev);
- } else if (result > 0 && host_byte(result) == DID_BAD_TARGET) {
- /*
- * If all LUNs of a virtio-scsi device are unplugged
- * it will respond with BAD TARGET on any INQUIRY
- * command.
- * Remove the device in this case as well.
- */
- scsi_remove_device(sdev);
- }
- }
- kfree(inq_result);
- }
- static void virtscsi_handle_event(struct work_struct *work)
- {
- struct virtio_scsi_event_node *event_node =
- container_of(work, struct virtio_scsi_event_node, work);
- struct virtio_scsi *vscsi = event_node->vscsi;
- struct virtio_scsi_event *event = &event_node->event;
- if (event->event &
- cpu_to_virtio32(vscsi->vdev, VIRTIO_SCSI_T_EVENTS_MISSED)) {
- event->event &= ~cpu_to_virtio32(vscsi->vdev,
- VIRTIO_SCSI_T_EVENTS_MISSED);
- virtscsi_rescan_hotunplug(vscsi);
- scsi_scan_host(virtio_scsi_host(vscsi->vdev));
- }
- switch (virtio32_to_cpu(vscsi->vdev, event->event)) {
- case VIRTIO_SCSI_T_NO_EVENT:
- break;
- case VIRTIO_SCSI_T_TRANSPORT_RESET:
- virtscsi_handle_transport_reset(vscsi, event);
- break;
- case VIRTIO_SCSI_T_PARAM_CHANGE:
- virtscsi_handle_param_change(vscsi, event);
- break;
- default:
- pr_err("Unsupported virtio scsi event %x\n", event->event);
- }
- virtscsi_kick_event(vscsi, event_node);
- }
- static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
- {
- struct virtio_scsi_event_node *event_node = buf;
- if (!vscsi->stop_events)
- queue_work(system_freezable_wq, &event_node->work);
- }
- static void virtscsi_event_done(struct virtqueue *vq)
- {
- struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
- struct virtio_scsi *vscsi = shost_priv(sh);
- virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event);
- };
- static int __virtscsi_add_cmd(struct virtqueue *vq,
- struct virtio_scsi_cmd *cmd,
- size_t req_size, size_t resp_size)
- {
- struct scsi_cmnd *sc = cmd->sc;
- struct scatterlist *sgs[6], req, resp;
- struct sg_table *out, *in;
- unsigned out_num = 0, in_num = 0;
- out = in = NULL;
- if (sc && sc->sc_data_direction != DMA_NONE) {
- if (sc->sc_data_direction != DMA_FROM_DEVICE)
- out = &sc->sdb.table;
- if (sc->sc_data_direction != DMA_TO_DEVICE)
- in = &sc->sdb.table;
- }
- /* Request header. */
- sg_init_one(&req, &cmd->req, req_size);
- sgs[out_num++] = &req;
- /* Data-out buffer. */
- if (out) {
- /* Place WRITE protection SGLs before Data OUT payload */
- if (scsi_prot_sg_count(sc))
- sgs[out_num++] = scsi_prot_sglist(sc);
- sgs[out_num++] = out->sgl;
- }
- /* Response header. */
- sg_init_one(&resp, &cmd->resp, resp_size);
- sgs[out_num + in_num++] = &resp;
- /* Data-in buffer */
- if (in) {
- /* Place READ protection SGLs before Data IN payload */
- if (scsi_prot_sg_count(sc))
- sgs[out_num + in_num++] = scsi_prot_sglist(sc);
- sgs[out_num + in_num++] = in->sgl;
- }
- return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC);
- }
- static void virtscsi_kick_vq(struct virtio_scsi_vq *vq)
- {
- bool needs_kick;
- unsigned long flags;
- spin_lock_irqsave(&vq->vq_lock, flags);
- needs_kick = virtqueue_kick_prepare(vq->vq);
- spin_unlock_irqrestore(&vq->vq_lock, flags);
- if (needs_kick)
- virtqueue_notify(vq->vq);
- }
- /**
- * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue, optionally kick it
- * @vq : the struct virtqueue we're talking about
- * @cmd : command structure
- * @req_size : size of the request buffer
- * @resp_size : size of the response buffer
- * @kick : whether to kick the virtqueue immediately
- */
- static int virtscsi_add_cmd(struct virtio_scsi_vq *vq,
- struct virtio_scsi_cmd *cmd,
- size_t req_size, size_t resp_size,
- bool kick)
- {
- unsigned long flags;
- int err;
- bool needs_kick = false;
- spin_lock_irqsave(&vq->vq_lock, flags);
- err = __virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size);
- if (!err && kick)
- needs_kick = virtqueue_kick_prepare(vq->vq);
- spin_unlock_irqrestore(&vq->vq_lock, flags);
- if (needs_kick)
- virtqueue_notify(vq->vq);
- return err;
- }
- static void virtio_scsi_init_hdr(struct virtio_device *vdev,
- struct virtio_scsi_cmd_req *cmd,
- struct scsi_cmnd *sc)
- {
- cmd->lun[0] = 1;
- cmd->lun[1] = sc->device->id;
- cmd->lun[2] = (sc->device->lun >> 8) | 0x40;
- cmd->lun[3] = sc->device->lun & 0xff;
- cmd->tag = cpu_to_virtio64(vdev, (unsigned long)sc);
- cmd->task_attr = VIRTIO_SCSI_S_SIMPLE;
- cmd->prio = 0;
- cmd->crn = 0;
- }
- #ifdef CONFIG_BLK_DEV_INTEGRITY
- static void virtio_scsi_init_hdr_pi(struct virtio_device *vdev,
- struct virtio_scsi_cmd_req_pi *cmd_pi,
- struct scsi_cmnd *sc)
- {
- struct request *rq = scsi_cmd_to_rq(sc);
- struct blk_integrity *bi;
- virtio_scsi_init_hdr(vdev, (struct virtio_scsi_cmd_req *)cmd_pi, sc);
- if (!rq || !scsi_prot_sg_count(sc))
- return;
- bi = blk_get_integrity(rq->q->disk);
- if (sc->sc_data_direction == DMA_TO_DEVICE)
- cmd_pi->pi_bytesout = cpu_to_virtio32(vdev,
- bio_integrity_bytes(bi,
- blk_rq_sectors(rq)));
- else if (sc->sc_data_direction == DMA_FROM_DEVICE)
- cmd_pi->pi_bytesin = cpu_to_virtio32(vdev,
- bio_integrity_bytes(bi,
- blk_rq_sectors(rq)));
- }
- #endif
- static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi,
- struct scsi_cmnd *sc)
- {
- u32 tag = blk_mq_unique_tag(scsi_cmd_to_rq(sc));
- u16 hwq = blk_mq_unique_tag_to_hwq(tag);
- return &vscsi->req_vqs[hwq];
- }
- static int virtscsi_queuecommand(struct Scsi_Host *shost,
- struct scsi_cmnd *sc)
- {
- struct virtio_scsi *vscsi = shost_priv(shost);
- struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc);
- struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc);
- bool kick;
- unsigned long flags;
- int req_size;
- int ret;
- BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize);
- /* TODO: check feature bit and fail if unsupported? */
- BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL);
- dev_dbg(&sc->device->sdev_gendev,
- "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]);
- cmd->sc = sc;
- BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE);
- #ifdef CONFIG_BLK_DEV_INTEGRITY
- if (virtio_has_feature(vscsi->vdev, VIRTIO_SCSI_F_T10_PI)) {
- virtio_scsi_init_hdr_pi(vscsi->vdev, &cmd->req.cmd_pi, sc);
- memcpy(cmd->req.cmd_pi.cdb, sc->cmnd, sc->cmd_len);
- req_size = sizeof(cmd->req.cmd_pi);
- } else
- #endif
- {
- virtio_scsi_init_hdr(vscsi->vdev, &cmd->req.cmd, sc);
- memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);
- req_size = sizeof(cmd->req.cmd);
- }
- kick = (sc->flags & SCMD_LAST) != 0;
- ret = virtscsi_add_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd), kick);
- if (ret == -EIO) {
- cmd->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
- spin_lock_irqsave(&req_vq->vq_lock, flags);
- virtscsi_complete_cmd(vscsi, cmd);
- spin_unlock_irqrestore(&req_vq->vq_lock, flags);
- } else if (ret != 0) {
- return SCSI_MLQUEUE_HOST_BUSY;
- }
- return 0;
- }
- static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
- {
- DECLARE_COMPLETION_ONSTACK(comp);
- int ret = FAILED;
- cmd->comp = ∁
- if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd,
- sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0)
- goto out;
- wait_for_completion(&comp);
- if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
- cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
- ret = SUCCESS;
- /*
- * The spec guarantees that all requests related to the TMF have
- * been completed, but the callback might not have run yet if
- * we're using independent interrupts (e.g. MSI). Poll the
- * virtqueues once.
- *
- * In the abort case, scsi_done() will do nothing, because the
- * command timed out and hence SCMD_STATE_COMPLETE has been set.
- */
- virtscsi_poll_requests(vscsi);
- out:
- mempool_free(cmd, virtscsi_cmd_pool);
- return ret;
- }
- static int virtscsi_device_reset(struct scsi_cmnd *sc)
- {
- struct virtio_scsi *vscsi = shost_priv(sc->device->host);
- struct virtio_scsi_cmd *cmd;
- sdev_printk(KERN_INFO, sc->device, "device reset\n");
- cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
- if (!cmd)
- return FAILED;
- memset(cmd, 0, sizeof(*cmd));
- cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
- .type = VIRTIO_SCSI_T_TMF,
- .subtype = cpu_to_virtio32(vscsi->vdev,
- VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET),
- .lun[0] = 1,
- .lun[1] = sc->device->id,
- .lun[2] = (sc->device->lun >> 8) | 0x40,
- .lun[3] = sc->device->lun & 0xff,
- };
- return virtscsi_tmf(vscsi, cmd);
- }
- static int virtscsi_device_alloc(struct scsi_device *sdevice)
- {
- /*
- * Passed through SCSI targets (e.g. with qemu's 'scsi-block')
- * may have transfer limits which come from the host SCSI
- * controller or something on the host side other than the
- * target itself.
- *
- * To make this work properly, the hypervisor can adjust the
- * target's VPD information to advertise these limits. But
- * for that to work, the guest has to look at the VPD pages,
- * which we won't do by default if it is an SPC-2 device, even
- * if it does actually support it.
- *
- * So, set the blist to always try to read the VPD pages.
- */
- sdevice->sdev_bflags = BLIST_TRY_VPD_PAGES;
- return 0;
- }
- /**
- * virtscsi_change_queue_depth() - Change a virtscsi target's queue depth
- * @sdev: Virtscsi target whose queue depth to change
- * @qdepth: New queue depth
- */
- static int virtscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
- {
- struct Scsi_Host *shost = sdev->host;
- int max_depth = shost->cmd_per_lun;
- return scsi_change_queue_depth(sdev, min(max_depth, qdepth));
- }
- static int virtscsi_abort(struct scsi_cmnd *sc)
- {
- struct virtio_scsi *vscsi = shost_priv(sc->device->host);
- struct virtio_scsi_cmd *cmd;
- scmd_printk(KERN_INFO, sc, "abort\n");
- cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
- if (!cmd)
- return FAILED;
- memset(cmd, 0, sizeof(*cmd));
- cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
- .type = VIRTIO_SCSI_T_TMF,
- .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,
- .lun[0] = 1,
- .lun[1] = sc->device->id,
- .lun[2] = (sc->device->lun >> 8) | 0x40,
- .lun[3] = sc->device->lun & 0xff,
- .tag = cpu_to_virtio64(vscsi->vdev, (unsigned long)sc),
- };
- return virtscsi_tmf(vscsi, cmd);
- }
- static void virtscsi_map_queues(struct Scsi_Host *shost)
- {
- struct virtio_scsi *vscsi = shost_priv(shost);
- struct blk_mq_queue_map *qmap = &shost->tag_set.map[HCTX_TYPE_DEFAULT];
- blk_mq_virtio_map_queues(qmap, vscsi->vdev, 2);
- }
- static void virtscsi_commit_rqs(struct Scsi_Host *shost, u16 hwq)
- {
- struct virtio_scsi *vscsi = shost_priv(shost);
- virtscsi_kick_vq(&vscsi->req_vqs[hwq]);
- }
- /*
- * The host guarantees to respond to each command, although I/O
- * latencies might be higher than on bare metal. Reset the timer
- * unconditionally to give the host a chance to perform EH.
- */
- static enum scsi_timeout_action virtscsi_eh_timed_out(struct scsi_cmnd *scmnd)
- {
- return SCSI_EH_RESET_TIMER;
- }
- static struct scsi_host_template virtscsi_host_template = {
- .module = THIS_MODULE,
- .name = "Virtio SCSI HBA",
- .proc_name = "virtio_scsi",
- .this_id = -1,
- .cmd_size = sizeof(struct virtio_scsi_cmd),
- .queuecommand = virtscsi_queuecommand,
- .commit_rqs = virtscsi_commit_rqs,
- .change_queue_depth = virtscsi_change_queue_depth,
- .eh_abort_handler = virtscsi_abort,
- .eh_device_reset_handler = virtscsi_device_reset,
- .eh_timed_out = virtscsi_eh_timed_out,
- .slave_alloc = virtscsi_device_alloc,
- .dma_boundary = UINT_MAX,
- .map_queues = virtscsi_map_queues,
- .track_queue_depth = 1,
- };
- #define virtscsi_config_get(vdev, fld) \
- ({ \
- __virtio_native_type(struct virtio_scsi_config, fld) __val; \
- virtio_cread(vdev, struct virtio_scsi_config, fld, &__val); \
- __val; \
- })
- #define virtscsi_config_set(vdev, fld, val) \
- do { \
- __virtio_native_type(struct virtio_scsi_config, fld) __val = (val); \
- virtio_cwrite(vdev, struct virtio_scsi_config, fld, &__val); \
- } while(0)
- static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
- struct virtqueue *vq)
- {
- spin_lock_init(&virtscsi_vq->vq_lock);
- virtscsi_vq->vq = vq;
- }
- static void virtscsi_remove_vqs(struct virtio_device *vdev)
- {
- /* Stop all the virtqueues. */
- virtio_reset_device(vdev);
- vdev->config->del_vqs(vdev);
- }
- static int virtscsi_init(struct virtio_device *vdev,
- struct virtio_scsi *vscsi)
- {
- int err;
- u32 i;
- u32 num_vqs;
- vq_callback_t **callbacks;
- const char **names;
- struct virtqueue **vqs;
- struct irq_affinity desc = { .pre_vectors = 2 };
- num_vqs = vscsi->num_queues + VIRTIO_SCSI_VQ_BASE;
- vqs = kmalloc_array(num_vqs, sizeof(struct virtqueue *), GFP_KERNEL);
- callbacks = kmalloc_array(num_vqs, sizeof(vq_callback_t *),
- GFP_KERNEL);
- names = kmalloc_array(num_vqs, sizeof(char *), GFP_KERNEL);
- if (!callbacks || !vqs || !names) {
- err = -ENOMEM;
- goto out;
- }
- callbacks[0] = virtscsi_ctrl_done;
- callbacks[1] = virtscsi_event_done;
- names[0] = "control";
- names[1] = "event";
- for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) {
- callbacks[i] = virtscsi_req_done;
- names[i] = "request";
- }
- /* Discover virtqueues and write information to configuration. */
- err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
- if (err)
- goto out;
- virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]);
- virtscsi_init_vq(&vscsi->event_vq, vqs[1]);
- for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++)
- virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE],
- vqs[i]);
- virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
- virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
- err = 0;
- out:
- kfree(names);
- kfree(callbacks);
- kfree(vqs);
- if (err)
- virtscsi_remove_vqs(vdev);
- return err;
- }
- static int virtscsi_probe(struct virtio_device *vdev)
- {
- struct Scsi_Host *shost;
- struct virtio_scsi *vscsi;
- int err;
- u32 sg_elems, num_targets;
- u32 cmd_per_lun;
- u32 num_queues;
- if (!vdev->config->get) {
- dev_err(&vdev->dev, "%s failure: config access disabled\n",
- __func__);
- return -EINVAL;
- }
- /* We need to know how many queues before we allocate. */
- num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;
- num_queues = min_t(unsigned int, nr_cpu_ids, num_queues);
- num_targets = virtscsi_config_get(vdev, max_target) + 1;
- shost = scsi_host_alloc(&virtscsi_host_template,
- struct_size(vscsi, req_vqs, num_queues));
- if (!shost)
- return -ENOMEM;
- sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
- shost->sg_tablesize = sg_elems;
- vscsi = shost_priv(shost);
- vscsi->vdev = vdev;
- vscsi->num_queues = num_queues;
- vdev->priv = shost;
- err = virtscsi_init(vdev, vscsi);
- if (err)
- goto virtscsi_init_failed;
- shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq);
- cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
- shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
- shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
- /* LUNs > 256 are reported with format 1, so they go in the range
- * 16640-32767.
- */
- shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000;
- shost->max_id = num_targets;
- shost->max_channel = 0;
- shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE;
- shost->nr_hw_queues = num_queues;
- #ifdef CONFIG_BLK_DEV_INTEGRITY
- if (virtio_has_feature(vdev, VIRTIO_SCSI_F_T10_PI)) {
- int host_prot;
- host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
- SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
- SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
- scsi_host_set_prot(shost, host_prot);
- scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC);
- }
- #endif
- err = scsi_add_host(shost, &vdev->dev);
- if (err)
- goto scsi_add_host_failed;
- virtio_device_ready(vdev);
- if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
- virtscsi_kick_event_all(vscsi);
- scsi_scan_host(shost);
- return 0;
- scsi_add_host_failed:
- vdev->config->del_vqs(vdev);
- virtscsi_init_failed:
- scsi_host_put(shost);
- return err;
- }
- static void virtscsi_remove(struct virtio_device *vdev)
- {
- struct Scsi_Host *shost = virtio_scsi_host(vdev);
- struct virtio_scsi *vscsi = shost_priv(shost);
- if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
- virtscsi_cancel_event_work(vscsi);
- scsi_remove_host(shost);
- virtscsi_remove_vqs(vdev);
- scsi_host_put(shost);
- }
- #ifdef CONFIG_PM_SLEEP
- static int virtscsi_freeze(struct virtio_device *vdev)
- {
- virtscsi_remove_vqs(vdev);
- return 0;
- }
- static int virtscsi_restore(struct virtio_device *vdev)
- {
- struct Scsi_Host *sh = virtio_scsi_host(vdev);
- struct virtio_scsi *vscsi = shost_priv(sh);
- int err;
- err = virtscsi_init(vdev, vscsi);
- if (err)
- return err;
- virtio_device_ready(vdev);
- if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
- virtscsi_kick_event_all(vscsi);
- return err;
- }
- #endif
- static struct virtio_device_id id_table[] = {
- { VIRTIO_ID_SCSI, VIRTIO_DEV_ANY_ID },
- { 0 },
- };
- static unsigned int features[] = {
- VIRTIO_SCSI_F_HOTPLUG,
- VIRTIO_SCSI_F_CHANGE,
- #ifdef CONFIG_BLK_DEV_INTEGRITY
- VIRTIO_SCSI_F_T10_PI,
- #endif
- };
- static struct virtio_driver virtio_scsi_driver = {
- .feature_table = features,
- .feature_table_size = ARRAY_SIZE(features),
- .driver.name = KBUILD_MODNAME,
- .driver.owner = THIS_MODULE,
- .id_table = id_table,
- .probe = virtscsi_probe,
- #ifdef CONFIG_PM_SLEEP
- .freeze = virtscsi_freeze,
- .restore = virtscsi_restore,
- #endif
- .remove = virtscsi_remove,
- };
- static int __init virtio_scsi_init(void)
- {
- int ret = -ENOMEM;
- virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0);
- if (!virtscsi_cmd_cache) {
- pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
- goto error;
- }
- virtscsi_cmd_pool =
- mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ,
- virtscsi_cmd_cache);
- if (!virtscsi_cmd_pool) {
- pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
- goto error;
- }
- ret = register_virtio_driver(&virtio_scsi_driver);
- if (ret < 0)
- goto error;
- return 0;
- error:
- mempool_destroy(virtscsi_cmd_pool);
- virtscsi_cmd_pool = NULL;
- kmem_cache_destroy(virtscsi_cmd_cache);
- virtscsi_cmd_cache = NULL;
- return ret;
- }
- static void __exit virtio_scsi_fini(void)
- {
- unregister_virtio_driver(&virtio_scsi_driver);
- mempool_destroy(virtscsi_cmd_pool);
- kmem_cache_destroy(virtscsi_cmd_cache);
- }
- module_init(virtio_scsi_init);
- module_exit(virtio_scsi_fini);
- MODULE_DEVICE_TABLE(virtio, id_table);
- MODULE_DESCRIPTION("Virtio SCSI HBA driver");
- MODULE_LICENSE("GPL");
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