diff options
Diffstat (limited to 'drivers/scsi/xen-scsifront.c')
| -rw-r--r-- | drivers/scsi/xen-scsifront.c | 217 |
1 files changed, 143 insertions, 74 deletions
diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c index 12c10a5e3d93..924025305753 100644 --- a/drivers/scsi/xen-scsifront.c +++ b/drivers/scsi/xen-scsifront.c @@ -58,9 +58,6 @@ #include <asm/xen/hypervisor.h> - -#define GRANT_INVALID_REF 0 - #define VSCSIFRONT_OP_ADD_LUN 1 #define VSCSIFRONT_OP_DEL_LUN 2 #define VSCSIFRONT_OP_READD_LUN 3 @@ -83,6 +80,8 @@ struct vscsifrnt_shadow { uint16_t rqid; uint16_t ref_rqid; + bool inflight; + unsigned int nr_grants; /* number of grants in gref[] */ struct scsiif_request_segment *sg; /* scatter/gather elements */ struct scsiif_request_segment seg[VSCSIIF_SG_TABLESIZE]; @@ -104,7 +103,11 @@ struct vscsifrnt_info { struct xenbus_device *dev; struct Scsi_Host *host; - int host_active; + enum { + STATE_INACTIVE, + STATE_ACTIVE, + STATE_ERROR + } host_active; unsigned int evtchn; unsigned int irq; @@ -217,6 +220,8 @@ static int scsifront_do_request(struct vscsifrnt_info *info, for (i = 0; i < (shadow->nr_segments & ~VSCSIIF_SG_GRANT); i++) ring_req->seg[i] = shadow->seg[i]; + shadow->inflight = true; + RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(ring, notify); if (notify) notify_remote_via_irq(info->irq); @@ -224,6 +229,13 @@ static int scsifront_do_request(struct vscsifrnt_info *info, return 0; } +static void scsifront_set_error(struct vscsifrnt_info *info, const char *msg) +{ + shost_printk(KERN_ERR, info->host, KBUILD_MODNAME "%s\n" + "Disabling device for further use\n", msg); + info->host_active = STATE_ERROR; +} + static void scsifront_gnttab_done(struct vscsifrnt_info *info, struct vscsifrnt_shadow *shadow) { @@ -233,17 +245,57 @@ static void scsifront_gnttab_done(struct vscsifrnt_info *info, return; for (i = 0; i < shadow->nr_grants; i++) { - if (unlikely(gnttab_query_foreign_access(shadow->gref[i]))) { - shost_printk(KERN_ALERT, info->host, KBUILD_MODNAME - "grant still in use by backend\n"); - BUG(); + if (unlikely(!gnttab_try_end_foreign_access(shadow->gref[i]))) { + scsifront_set_error(info, "grant still in use by backend"); + return; } - gnttab_end_foreign_access(shadow->gref[i], 0, 0UL); } kfree(shadow->sg); } +static unsigned int scsifront_host_byte(int32_t rslt) +{ + switch (XEN_VSCSIIF_RSLT_HOST(rslt)) { + case XEN_VSCSIIF_RSLT_HOST_OK: + return DID_OK; + case XEN_VSCSIIF_RSLT_HOST_NO_CONNECT: + return DID_NO_CONNECT; + case XEN_VSCSIIF_RSLT_HOST_BUS_BUSY: + return DID_BUS_BUSY; + case XEN_VSCSIIF_RSLT_HOST_TIME_OUT: + return DID_TIME_OUT; + case XEN_VSCSIIF_RSLT_HOST_BAD_TARGET: + return DID_BAD_TARGET; + case XEN_VSCSIIF_RSLT_HOST_ABORT: + return DID_ABORT; + case XEN_VSCSIIF_RSLT_HOST_PARITY: + return DID_PARITY; + case XEN_VSCSIIF_RSLT_HOST_ERROR: + return DID_ERROR; + case XEN_VSCSIIF_RSLT_HOST_RESET: + return DID_RESET; + case XEN_VSCSIIF_RSLT_HOST_BAD_INTR: + return DID_BAD_INTR; + case XEN_VSCSIIF_RSLT_HOST_PASSTHROUGH: + return DID_PASSTHROUGH; + case XEN_VSCSIIF_RSLT_HOST_SOFT_ERROR: + return DID_SOFT_ERROR; + case XEN_VSCSIIF_RSLT_HOST_IMM_RETRY: + return DID_IMM_RETRY; + case XEN_VSCSIIF_RSLT_HOST_REQUEUE: + return DID_REQUEUE; + case XEN_VSCSIIF_RSLT_HOST_TRANSPORT_DISRUPTED: + return DID_TRANSPORT_DISRUPTED; + case XEN_VSCSIIF_RSLT_HOST_TRANSPORT_FAILFAST: + return DID_TRANSPORT_FAILFAST; + case XEN_VSCSIIF_RSLT_HOST_TRANSPORT_MARGINAL: + return DID_TRANSPORT_MARGINAL; + default: + return DID_ERROR; + } +} + static void scsifront_cdb_cmd_done(struct vscsifrnt_info *info, struct vscsiif_response *ring_rsp) { @@ -251,7 +303,6 @@ static void scsifront_cdb_cmd_done(struct vscsifrnt_info *info, struct scsi_cmnd *sc; uint32_t id; uint8_t sense_len; - int result; id = ring_rsp->rqid; shadow = info->shadow[id]; @@ -260,14 +311,12 @@ static void scsifront_cdb_cmd_done(struct vscsifrnt_info *info, BUG_ON(sc == NULL); scsifront_gnttab_done(info, shadow); + if (info->host_active == STATE_ERROR) + return; scsifront_put_rqid(info, id); - result = ring_rsp->rslt; - if (result >> 24) - set_host_byte(sc, DID_ERROR); - else - set_host_byte(sc, host_byte(result)); - set_status_byte(sc, result & 0xff); + set_host_byte(sc, scsifront_host_byte(ring_rsp->rslt)); + set_status_byte(sc, XEN_VSCSIIF_RSLT_STATUS(ring_rsp->rslt)); scsi_set_resid(sc, ring_rsp->residual_len); sense_len = min_t(uint8_t, VSCSIIF_SENSE_BUFFERSIZE, @@ -291,7 +340,10 @@ static void scsifront_sync_cmd_done(struct vscsifrnt_info *info, shadow->wait_reset = 1; switch (shadow->rslt_reset) { case RSLT_RESET_WAITING: - shadow->rslt_reset = ring_rsp->rslt; + if (ring_rsp->rslt == XEN_VSCSIIF_RSLT_RESET_SUCCESS) + shadow->rslt_reset = SUCCESS; + else + shadow->rslt_reset = FAILED; break; case RSLT_RESET_ERR: kick = _scsifront_put_rqid(info, id); @@ -301,9 +353,7 @@ static void scsifront_sync_cmd_done(struct vscsifrnt_info *info, scsifront_wake_up(info); return; default: - shost_printk(KERN_ERR, info->host, KBUILD_MODNAME - "bad reset state %d, possibly leaking %u\n", - shadow->rslt_reset, id); + scsifront_set_error(info, "bad reset state"); break; } spin_unlock_irqrestore(&info->shadow_lock, flags); @@ -314,28 +364,41 @@ static void scsifront_sync_cmd_done(struct vscsifrnt_info *info, static void scsifront_do_response(struct vscsifrnt_info *info, struct vscsiif_response *ring_rsp) { - if (WARN(ring_rsp->rqid >= VSCSIIF_MAX_REQS || - test_bit(ring_rsp->rqid, info->shadow_free_bitmap), - "illegal rqid %u returned by backend!\n", ring_rsp->rqid)) + struct vscsifrnt_shadow *shadow; + + if (ring_rsp->rqid >= VSCSIIF_MAX_REQS || + !info->shadow[ring_rsp->rqid]->inflight) { + scsifront_set_error(info, "illegal rqid returned by backend!"); return; + } + shadow = info->shadow[ring_rsp->rqid]; + shadow->inflight = false; - if (info->shadow[ring_rsp->rqid]->act == VSCSIIF_ACT_SCSI_CDB) + if (shadow->act == VSCSIIF_ACT_SCSI_CDB) scsifront_cdb_cmd_done(info, ring_rsp); else scsifront_sync_cmd_done(info, ring_rsp); } -static int scsifront_ring_drain(struct vscsifrnt_info *info) +static int scsifront_ring_drain(struct vscsifrnt_info *info, + unsigned int *eoiflag) { - struct vscsiif_response *ring_rsp; + struct vscsiif_response ring_rsp; RING_IDX i, rp; int more_to_do = 0; - rp = info->ring.sring->rsp_prod; - rmb(); /* ordering required respective to dom0 */ + rp = READ_ONCE(info->ring.sring->rsp_prod); + virt_rmb(); /* ordering required respective to backend */ + if (RING_RESPONSE_PROD_OVERFLOW(&info->ring, rp)) { + scsifront_set_error(info, "illegal number of responses"); + return 0; + } for (i = info->ring.rsp_cons; i != rp; i++) { - ring_rsp = RING_GET_RESPONSE(&info->ring, i); - scsifront_do_response(info, ring_rsp); + RING_COPY_RESPONSE(&info->ring, i, &ring_rsp); + scsifront_do_response(info, &ring_rsp); + if (info->host_active == STATE_ERROR) + return 0; + *eoiflag &= ~XEN_EOI_FLAG_SPURIOUS; } info->ring.rsp_cons = i; @@ -348,14 +411,15 @@ static int scsifront_ring_drain(struct vscsifrnt_info *info) return more_to_do; } -static int scsifront_cmd_done(struct vscsifrnt_info *info) +static int scsifront_cmd_done(struct vscsifrnt_info *info, + unsigned int *eoiflag) { int more_to_do; unsigned long flags; spin_lock_irqsave(info->host->host_lock, flags); - more_to_do = scsifront_ring_drain(info); + more_to_do = scsifront_ring_drain(info, eoiflag); info->wait_ring_available = 0; @@ -369,20 +433,28 @@ static int scsifront_cmd_done(struct vscsifrnt_info *info) static irqreturn_t scsifront_irq_fn(int irq, void *dev_id) { struct vscsifrnt_info *info = dev_id; + unsigned int eoiflag = XEN_EOI_FLAG_SPURIOUS; + + if (info->host_active == STATE_ERROR) { + xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); + return IRQ_HANDLED; + } - while (scsifront_cmd_done(info)) + while (scsifront_cmd_done(info, &eoiflag)) /* Yield point for this unbounded loop. */ cond_resched(); + xen_irq_lateeoi(irq, eoiflag); + return IRQ_HANDLED; } static void scsifront_finish_all(struct vscsifrnt_info *info) { - unsigned i; + unsigned int i, dummy; struct vscsiif_response resp; - scsifront_ring_drain(info); + scsifront_ring_drain(info, &dummy); for (i = 0; i < VSCSIIF_MAX_REQS; i++) { if (test_bit(i, info->shadow_free_bitmap)) @@ -539,6 +611,9 @@ static int scsifront_queuecommand(struct Scsi_Host *shost, unsigned long flags; int err; + if (info->host_active == STATE_ERROR) + return SCSI_MLQUEUE_HOST_BUSY; + sc->result = 0; shadow->sc = sc; @@ -591,6 +666,9 @@ static int scsifront_action_handler(struct scsi_cmnd *sc, uint8_t act) struct vscsifrnt_shadow *shadow, *s = scsi_cmd_priv(sc); int err = 0; + if (info->host_active == STATE_ERROR) + return FAILED; + shadow = kzalloc(sizeof(*shadow), GFP_NOIO); if (!shadow) return FAILED; @@ -657,12 +735,16 @@ static int scsifront_dev_reset_handler(struct scsi_cmnd *sc) return scsifront_action_handler(sc, VSCSIIF_ACT_SCSI_RESET); } -static int scsifront_sdev_configure(struct scsi_device *sdev) +static int scsifront_sdev_configure(struct scsi_device *sdev, + struct queue_limits *lim) { struct vscsifrnt_info *info = shost_priv(sdev->host); int err; - if (info && current == info->curr) { + if (info->host_active == STATE_ERROR) + return -EIO; + + if (current == info->curr) { err = xenbus_printf(XBT_NIL, info->dev->nodename, info->dev_state_path, "%d", XenbusStateConnected); if (err) { @@ -680,7 +762,7 @@ static void scsifront_sdev_destroy(struct scsi_device *sdev) struct vscsifrnt_info *info = shost_priv(sdev->host); int err; - if (info && current == info->curr) { + if (current == info->curr) { err = xenbus_printf(XBT_NIL, info->dev->nodename, info->dev_state_path, "%d", XenbusStateClosed); if (err) @@ -689,14 +771,14 @@ static void scsifront_sdev_destroy(struct scsi_device *sdev) } } -static struct scsi_host_template scsifront_sht = { +static const struct scsi_host_template scsifront_sht = { .module = THIS_MODULE, .name = "Xen SCSI frontend driver", .queuecommand = scsifront_queuecommand, .eh_abort_handler = scsifront_eh_abort_handler, .eh_device_reset_handler = scsifront_dev_reset_handler, - .slave_configure = scsifront_sdev_configure, - .slave_destroy = scsifront_sdev_destroy, + .sdev_configure = scsifront_sdev_configure, + .sdev_destroy = scsifront_sdev_destroy, .cmd_per_lun = VSCSIIF_DEFAULT_CMD_PER_LUN, .can_queue = VSCSIIF_MAX_REQS, .this_id = -1, @@ -709,27 +791,15 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info) { struct xenbus_device *dev = info->dev; struct vscsiif_sring *sring; - grant_ref_t gref; - int err = -ENOMEM; + int err; /***** Frontend to Backend ring start *****/ - sring = (struct vscsiif_sring *)__get_free_page(GFP_KERNEL); - if (!sring) { - xenbus_dev_fatal(dev, err, - "fail to allocate shared ring (Front to Back)"); + err = xenbus_setup_ring(dev, GFP_KERNEL, (void **)&sring, 1, + &info->ring_ref); + if (err) return err; - } - SHARED_RING_INIT(sring); - FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE); - err = xenbus_grant_ring(dev, sring, 1, &gref); - if (err < 0) { - free_page((unsigned long)sring); - xenbus_dev_fatal(dev, err, - "fail to grant shared ring (Front to Back)"); - return err; - } - info->ring_ref = gref; + XEN_FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE); err = xenbus_alloc_evtchn(dev, &info->evtchn); if (err) { @@ -737,7 +807,7 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info) goto free_gnttab; } - err = bind_evtchn_to_irq(info->evtchn); + err = bind_evtchn_to_irq_lateeoi(info->evtchn); if (err <= 0) { xenbus_dev_fatal(dev, err, "bind_evtchn_to_irq"); goto free_gnttab; @@ -758,8 +828,7 @@ static int scsifront_alloc_ring(struct vscsifrnt_info *info) free_irq: unbind_from_irqhandler(info->irq, info); free_gnttab: - gnttab_end_foreign_access(info->ring_ref, 0, - (unsigned long)info->ring.sring); + xenbus_teardown_ring((void **)&sring, 1, &info->ring_ref); return err; } @@ -767,8 +836,7 @@ free_gnttab: static void scsifront_free_ring(struct vscsifrnt_info *info) { unbind_from_irqhandler(info->irq, info); - gnttab_end_foreign_access(info->ring_ref, 0, - (unsigned long)info->ring.sring); + xenbus_teardown_ring((void **)&info->ring.sring, 1, &info->ring_ref); } static int scsifront_init_ring(struct vscsifrnt_info *info) @@ -836,7 +904,7 @@ static int scsifront_probe(struct xenbus_device *dev, xenbus_dev_fatal(dev, err, "fail to allocate scsi host"); return err; } - info = (struct vscsifrnt_info *)host->hostdata; + info = shost_priv(host); dev_set_drvdata(&dev->dev, info); info->dev = dev; @@ -867,7 +935,7 @@ static int scsifront_probe(struct xenbus_device *dev, goto free_sring; } info->host = host; - info->host_active = 1; + info->host_active = STATE_ACTIVE; xenbus_switch_state(dev, XenbusStateInitialised); @@ -928,24 +996,22 @@ static int scsifront_suspend(struct xenbus_device *dev) return err; } -static int scsifront_remove(struct xenbus_device *dev) +static void scsifront_remove(struct xenbus_device *dev) { struct vscsifrnt_info *info = dev_get_drvdata(&dev->dev); pr_debug("%s: %s removed\n", __func__, dev->nodename); mutex_lock(&scsifront_mutex); - if (info->host_active) { + if (info->host_active != STATE_INACTIVE) { /* Scsi_host not yet removed */ scsi_remove_host(info->host); - info->host_active = 0; + info->host_active = STATE_INACTIVE; } mutex_unlock(&scsifront_mutex); scsifront_free_ring(info); scsi_host_put(info->host); - - return 0; } static void scsifront_disconnect(struct vscsifrnt_info *info) @@ -962,9 +1028,9 @@ static void scsifront_disconnect(struct vscsifrnt_info *info) */ mutex_lock(&scsifront_mutex); - if (info->host_active) { + if (info->host_active != STATE_INACTIVE) { scsi_remove_host(host); - info->host_active = 0; + info->host_active = STATE_INACTIVE; } mutex_unlock(&scsifront_mutex); @@ -982,6 +1048,9 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op) unsigned int hst, chn, tgt, lun; struct scsi_device *sdev; + if (info->host_active == STATE_ERROR) + return; + dir = xenbus_directory(XBT_NIL, dev->otherend, "vscsi-devs", &dir_n); if (IS_ERR(dir)) return; @@ -1006,8 +1075,8 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op) continue; /* - * Front device state path, used in slave_configure called - * on successfull scsi_add_device, and in slave_destroy called + * Front device state path, used in sdev_configure called + * on successfull scsi_add_device, and in sdev_destroy called * on remove of a device. */ snprintf(info->dev_state_path, sizeof(info->dev_state_path), |