// SPDX-License-Identifier: GPL-2.0 /* * scsi_scan.c * * Copyright (C) 2000 Eric Youngdale, * Copyright (C) 2002 Patrick Mansfield * * The general scanning/probing algorithm is as follows, exceptions are * made to it depending on device specific flags, compilation options, and * global variable (boot or module load time) settings. * * A specific LUN is scanned via an INQUIRY command; if the LUN has a * device attached, a scsi_device is allocated and setup for it. * * For every id of every channel on the given host: * * Scan LUN 0; if the target responds to LUN 0 (even if there is no * device or storage attached to LUN 0): * * If LUN 0 has a device attached, allocate and setup a * scsi_device for it. * * If target is SCSI-3 or up, issue a REPORT LUN, and scan * all of the LUNs returned by the REPORT LUN; else, * sequentially scan LUNs up until some maximum is reached, * or a LUN is seen that cannot have a device attached to it. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "scsi_priv.h" #include "scsi_logging.h" #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \ " SCSI scanning, some SCSI devices might not be configured\n" /* * Default timeout */ #define SCSI_TIMEOUT (2*HZ) #define SCSI_REPORT_LUNS_TIMEOUT (30*HZ) /* * Prefix values for the SCSI id's (stored in sysfs name field) */ #define SCSI_UID_SER_NUM 'S' #define SCSI_UID_UNKNOWN 'Z' /* * Return values of some of the scanning functions. * * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this * includes allocation or general failures preventing IO from being sent. * * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available * on the given LUN. * * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a * given LUN. */ #define SCSI_SCAN_NO_RESPONSE 0 #define SCSI_SCAN_TARGET_PRESENT 1 #define SCSI_SCAN_LUN_PRESENT 2 static const char *scsi_null_device_strs = "nullnullnullnull"; #define MAX_SCSI_LUNS 512 static u64 max_scsi_luns = MAX_SCSI_LUNS; module_param_named(max_luns, max_scsi_luns, ullong, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(max_luns, "last scsi LUN (should be between 1 and 2^64-1)"); #ifdef CONFIG_SCSI_SCAN_ASYNC #define SCSI_SCAN_TYPE_DEFAULT "async" #else #define SCSI_SCAN_TYPE_DEFAULT "sync" #endif char scsi_scan_type[7] = SCSI_SCAN_TYPE_DEFAULT; module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO|S_IWUSR); MODULE_PARM_DESC(scan, "sync, async, manual, or none. " "Setting to 'manual' disables automatic scanning, but allows " "for manual device scan via the 'scan' sysfs attribute."); static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18; module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(inq_timeout, "Timeout (in seconds) waiting for devices to answer INQUIRY." " Default is 20. Some devices may need more; most need less."); /* This lock protects only this list */ static DEFINE_SPINLOCK(async_scan_lock); static LIST_HEAD(scanning_hosts); struct async_scan_data { struct list_head list; struct Scsi_Host *shost; struct completion prev_finished; }; /** * scsi_complete_async_scans - Wait for asynchronous scans to complete * * When this function returns, any host which started scanning before * this function was called will have finished its scan. Hosts which * started scanning after this function was called may or may not have * finished. */ int scsi_complete_async_scans(void) { struct async_scan_data *data; do { if (list_empty(&scanning_hosts)) return 0; /* If we can't get memory immediately, that's OK. Just * sleep a little. Even if we never get memory, the async * scans will finish eventually. */ data = kmalloc(sizeof(*data), GFP_KERNEL); if (!data) msleep(1); } while (!data); data->shost = NULL; init_completion(&data->prev_finished); spin_lock(&async_scan_lock); /* Check that there's still somebody else on the list */ if (list_empty(&scanning_hosts)) goto done; list_add_tail(&data->list, &scanning_hosts); spin_unlock(&async_scan_lock); printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); wait_for_completion(&data->prev_finished); spin_lock(&async_scan_lock); list_del(&data->list); if (!list_empty(&scanning_hosts)) { struct async_scan_data *next = list_entry(scanning_hosts.next, struct async_scan_data, list); complete(&next->prev_finished); } done: spin_unlock(&async_scan_lock); kfree(data); return 0; } /** * scsi_unlock_floptical - unlock device via a special MODE SENSE command * @sdev: scsi device to send command to * @result: area to store the result of the MODE SENSE * * Description: * Send a vendor specific MODE SENSE (not a MODE SELECT) command. * Called for BLIST_KEY devices. **/ static void scsi_unlock_floptical(struct scsi_device *sdev, unsigned char *result) { unsigned char scsi_cmd[MAX_COMMAND_SIZE]; sdev_printk(KERN_NOTICE, sdev, "unlocking floptical drive\n"); scsi_cmd[0] = MODE_SENSE; scsi_cmd[1] = 0; scsi_cmd[2] = 0x2e; scsi_cmd[3] = 0; scsi_cmd[4] = 0x2a; /* size */ scsi_cmd[5] = 0; scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, SCSI_TIMEOUT, 3, NULL); } static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev, unsigned int depth) { int new_shift = sbitmap_calculate_shift(depth); bool need_alloc = !sdev->budget_map.map; bool need_free = false; int ret; struct sbitmap sb_backup; depth = min_t(unsigned int, depth, scsi_device_max_queue_depth(sdev)); /* * realloc if new shift is calculated, which is caused by setting * up one new default queue depth after calling ->slave_configure */ if (!need_alloc && new_shift != sdev->budget_map.shift) need_alloc = need_free = true; if (!need_alloc) return 0; /* * Request queue has to be frozen for reallocating budget map, * and here disk isn't added yet, so freezing is pretty fast */ if (need_free) { blk_mq_freeze_queue(sdev->request_queue); sb_backup = sdev->budget_map; } ret = sbitmap_init_node(&sdev->budget_map, scsi_device_max_queue_depth(sdev), new_shift, GFP_KERNEL, sdev->request_queue->node, false, true); if (!ret) sbitmap_resize(&sdev->budget_map, depth); if (need_free) { if (ret) sdev->budget_map = sb_backup; else sbitmap_free(&sb_backup); ret = 0; blk_mq_unfreeze_queue(sdev->request_queue); } return ret; } /** * scsi_alloc_sdev - allocate and setup a scsi_Device * @starget: which target to allocate a &scsi_device for * @lun: which lun * @hostdata: usually NULL and set by ->slave_alloc instead * * Description: * Allocate, initialize for io, and return a pointer to a scsi_Device. * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and * adds scsi_Device to the appropriate list. * * Return value: * scsi_Device pointer, or NULL on failure. **/ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, u64 lun, void *hostdata) { unsigned int depth; struct scsi_device *sdev; struct request_queue *q; int display_failure_msg = 1, ret; struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, GFP_KERNEL); if (!sdev) goto out; sdev->vendor = scsi_null_device_strs; sdev->model = scsi_null_device_strs; sdev->rev = scsi_null_device_strs; sdev->host = shost; sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD; sdev->id = starget->id; sdev->lun = lun; sdev->channel = starget->channel; mutex_init(&sdev->state_mutex); sdev->sdev_state = SDEV_CREATED; INIT_LIST_HEAD(&sdev->siblings); INIT_LIST_HEAD(&sdev->same_target_siblings); INIT_LIST_HEAD(&sdev->starved_entry); INIT_LIST_HEAD(&sdev->event_list); spin_lock_init(&sdev->list_lock); mutex_init(&sdev->inquiry_mutex); INIT_WORK(&sdev->event_work, scsi_evt_thread); INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue); sdev->sdev_gendev.parent = get_device(&starget->dev); sdev->sdev_target = starget; /* usually NULL and set by ->slave_alloc instead */ sdev->hostdata = hostdata; /* if the device needs this changing, it may do so in the * slave_configure function */ sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; /* * Some low level driver could use device->type */ sdev->type = -1; /* * Assume that the device will have handshaking problems, * and then fix this field later if it turns out it * doesn't */ sdev->borken = 1; sdev->sg_reserved_size = INT_MAX; q = blk_mq_init_queue(&sdev->host->tag_set); if (IS_ERR(q)) { /* release fn is set up in scsi_sysfs_device_initialise, so * have to free and put manually here */ put_device(&starget->dev); kfree(sdev); goto out; } sdev->request_queue = q; q->queuedata = sdev; __scsi_init_queue(sdev->host, q); blk_queue_flag_set(QUEUE_FLAG_SCSI_PASSTHROUGH, q); WARN_ON_ONCE(!blk_get_queue(q)); depth = sdev->host->cmd_per_lun ?: 1; /* * Use .can_queue as budget map's depth because we have to * support adjusting queue depth from sysfs. Meantime use * default device queue depth to figure out sbitmap shift * since we use this queue depth most of times. */ if (scsi_realloc_sdev_budget_map(sdev, depth)) { put_device(&starget->dev); kfree(sdev); goto out; } scsi_change_queue_depth(sdev, depth); scsi_sysfs_device_initialize(sdev); if (shost->hostt->slave_alloc) { ret = shost->hostt->slave_alloc(sdev); if (ret) { /* * if LLDD reports slave not present, don't clutter * console with alloc failure messages */ if (ret == -ENXIO) display_failure_msg = 0; goto out_device_destroy; } } return sdev; out_device_destroy: __scsi_remove_device(sdev); out: if (display_failure_msg) printk(ALLOC_FAILURE_MSG, __func__); return NULL; } static void scsi_target_destroy(struct scsi_target *starget) { struct device *dev = &starget->dev; struct Scsi_Host *shost = dev_to_shost(dev->parent); unsigned long flags; BUG_ON(starget->state == STARGET_DEL); starget->state = STARGET_DEL; transport_destroy_device(dev); spin_lock_irqsave(shost->host_lock, flags); if (shost->hostt->target_destroy) shost->hostt->target_destroy(starget); list_del_init(&starget->siblings); spin_unlock_irqrestore(shost->host_lock, flags); put_device(dev); } static void scsi_target_dev_release(struct device *dev) { struct device *parent = dev->parent; struct scsi_target *starget = to_scsi_target(dev); kfree(starget); put_device(parent); } static struct device_type scsi_target_type = { .name = "scsi_target", .release = scsi_target_dev_release, }; int scsi_is_target_device(const struct device *dev) { return dev->type == &scsi_target_type; } EXPORT_SYMBOL(scsi_is_target_device); static struct scsi_target *__scsi_find_target(struct device *parent, int channel, uint id) { struct scsi_target *starget, *found_starget = NULL; struct Scsi_Host *shost = dev_to_shost(parent); /* * Search for an existing target for this sdev. */ list_for_each_entry(starget, &shost->__targets, siblings) { if (starget->id == id && starget->channel == channel) { found_starget = starget; break; } } if (found_starget) get_device(&found_starget->dev); return found_starget; } /** * scsi_target_reap_ref_release - remove target from visibility * @kref: the reap_ref in the target being released * * Called on last put of reap_ref, which is the indication that no device * under this target is visible anymore, so render the target invisible in * sysfs. Note: we have to be in user context here because the target reaps * should be done in places where the scsi device visibility is being removed. */ static void scsi_target_reap_ref_release(struct kref *kref) { struct scsi_target *starget = container_of(kref, struct scsi_target, reap_ref); /* * if we get here and the target is still in a CREATED state that * means it was allocated but never made visible (because a scan * turned up no LUNs), so don't call device_del() on it. */ if ((starget->state != STARGET_CREATED) && (starget->state != STARGET_CREATED_REMOVE)) { transport_remove_device(&starget->dev); device_del(&starget->dev); } scsi_target_destroy(starget); } static void scsi_target_reap_ref_put(struct scsi_target *starget) { kref_put(&starget->reap_ref, scsi_target_reap_ref_release); } /** * scsi_alloc_target - allocate a new or find an existing target * @parent: parent of the target (need not be a scsi host) * @channel: target channel number (zero if no channels) * @id: target id number * * Return an existing target if one exists, provided it hasn't already * gone into STARGET_DEL state, otherwise allocate a new target. * * The target is returned with an incremented reference, so the caller * is responsible for both reaping and doing a last put */ static struct scsi_target *scsi_alloc_target(struct device *parent, int channel, uint id) { struct Scsi_Host *shost = dev_to_shost(parent); struct device *dev = NULL; unsigned long flags; const int size = sizeof(struct scsi_target) + shost->transportt->target_size; struct scsi_target *starget; struct scsi_target *found_target; int error, ref_got; starget = kzalloc(size, GFP_KERNEL); if (!starget) { printk(KERN_ERR "%s: allocation failure\n", __func__); return NULL; } dev = &starget->dev; device_initialize(dev); kref_init(&starget->reap_ref); dev->parent = get_device(parent); dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id); dev->bus = &scsi_bus_type; dev->type = &scsi_target_type; starget->id = id; starget->channel = channel; starget->can_queue = 0; INIT_LIST_HEAD(&starget->siblings); INIT_LIST_HEAD(&starget->devices); starget->state = STARGET_CREATED; starget->scsi_level = SCSI_2; starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED; retry: spin_lock_irqsave(shost->host_lock, flags); found_target = __scsi_find_target(parent, channel, id); if (found_target) goto found; list_add_tail(&starget->siblings, &shost->__targets); spin_unlock_irqrestore(shost->host_lock, flags); /* allocate and add */ transport_setup_device(dev); if (shost->hostt->target_alloc) { error = shost->hostt->target_alloc(starget); if(error) { if (error != -ENXIO) dev_err(dev, "target allocation failed, error %d\n", error); /* don't want scsi_target_reap to do the final * put because it will be under the host lock */ scsi_target_destroy(starget); return NULL; } } get_device(dev); return starget; found: /* * release routine already fired if kref is zero, so if we can still * take the reference, the target must be alive. If we can't, it must * be dying and we need to wait for a new target */ ref_got = kref_get_unless_zero(&found_target->reap_ref); spin_unlock_irqrestore(shost->host_lock, flags); if (ref_got) { put_device(dev); return found_target; } /* * Unfortunately, we found a dying target; need to wait until it's * dead before we can get a new one. There is an anomaly here. We * *should* call scsi_target_reap() to balance the kref_get() of the * reap_ref above. However, since the target being released, it's * already invisible and the reap_ref is irrelevant. If we call * scsi_target_reap() we might spuriously do another device_del() on * an already invisible target. */ put_device(&found_target->dev); /* * length of time is irrelevant here, we just want to yield the CPU * for a tick to avoid busy waiting for the target to die. */ msleep(1); goto retry; } /** * scsi_target_reap - check to see if target is in use and destroy if not * @starget: target to be checked * * This is used after removing a LUN or doing a last put of the target * it checks atomically that nothing is using the target and removes * it if so. */ void scsi_target_reap(struct scsi_target *starget) { /* * serious problem if this triggers: STARGET_DEL is only set in the if * the reap_ref drops to zero, so we're trying to do another final put * on an already released kref */ BUG_ON(starget->state == STARGET_DEL); scsi_target_reap_ref_put(starget); } /** * scsi_sanitize_inquiry_string - remove non-graphical chars from an * INQUIRY result string * @s: INQUIRY result string to sanitize * @len: length of the string * * Description: * The SCSI spec says that INQUIRY vendor, product, and revision * strings must consist entirely of graphic ASCII characters, * padded on the right with spaces. Since not all devices obey * this rule, we will replace non-graphic or non-ASCII characters * with spaces. Exception: a NUL character is interpreted as a * string terminator, so all the following characters are set to * spaces. **/ void scsi_sanitize_inquiry_string(unsigned char *s, int len) { int terminated = 0; for (; len > 0; (--len, ++s)) { if (*s == 0) terminated = 1; if (terminated || *s < 0x20 || *s > 0x7e) *s = ' '; } } EXPORT_SYMBOL(scsi_sanitize_inquiry_string); /** * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY * @sdev: scsi_device to probe * @inq_result: area to store the INQUIRY result * @result_len: len of inq_result * @bflags: store any bflags found here * * Description: * Probe the lun associated with @req using a standard SCSI INQUIRY; * * If the INQUIRY is successful, zero is returned and the * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length * are copied to the scsi_device any flags value is stored in *@bflags. **/ static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, int result_len, blist_flags_t *bflags) { unsigned char scsi_cmd[MAX_COMMAND_SIZE]; int first_inquiry_len, try_inquiry_len, next_inquiry_len; int response_len = 0; int pass, count, result; struct scsi_sense_hdr sshdr; *bflags = 0; /* Perform up to 3 passes. The first pass uses a conservative * transfer length of 36 unless sdev->inquiry_len specifies a * different value. */ first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36; try_inquiry_len = first_inquiry_len; pass = 1; next_pass: SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, "scsi scan: INQUIRY pass %d length %d\n", pass, try_inquiry_len)); /* Each pass gets up to three chances to ignore Unit Attention */ for (count = 0; count < 3; ++count) { int resid; memset(scsi_cmd, 0, 6); scsi_cmd[0] = INQUIRY; scsi_cmd[4] = (unsigned char) try_inquiry_len; memset(inq_result, 0, try_inquiry_len); result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, inq_result, try_inquiry_len, &sshdr, HZ / 2 + HZ * scsi_inq_timeout, 3, &resid); SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, "scsi scan: INQUIRY %s with code 0x%x\n", result ? "failed" : "successful", result)); if (result > 0) { /* * not-ready to ready transition [asc/ascq=0x28/0x0] * or power-on, reset [asc/ascq=0x29/0x0], continue. * INQUIRY should not yield UNIT_ATTENTION * but many buggy devices do so anyway. */ if (scsi_status_is_check_condition(result) && scsi_sense_valid(&sshdr)) { if ((sshdr.sense_key == UNIT_ATTENTION) && ((sshdr.asc == 0x28) || (sshdr.asc == 0x29)) && (sshdr.ascq == 0)) continue; } } else if (result == 0) { /* * if nothing was transferred, we try * again. It's a workaround for some USB * devices. */ if (resid == try_inquiry_len) continue; } break; } if (result == 0) { scsi_sanitize_inquiry_string(&inq_result[8], 8); scsi_sanitize_inquiry_string(&inq_result[16], 16); scsi_sanitize_inquiry_string(&inq_result[32], 4); response_len = inq_result[4] + 5; if (response_len > 255) response_len = first_inquiry_len; /* sanity */ /* * Get any flags for this device. * * XXX add a bflags to scsi_device, and replace the * corresponding bit fields in scsi_device, so bflags * need not be passed as an argument. */ *bflags = scsi_get_device_flags(sdev, &inq_result[8], &inq_result[16]); /* When the first pass succeeds we gain information about * what larger transfer lengths might work. */ if (pass == 1) { if (BLIST_INQUIRY_36 & *bflags) next_inquiry_len = 36; else if (sdev->inquiry_len) next_inquiry_len = sdev->inquiry_len; else next_inquiry_len = response_len; /* If more data is available perform the second pass */ if (next_inquiry_len > try_inquiry_len) { try_inquiry_len = next_inquiry_len; pass = 2; goto next_pass; } } } else if (pass == 2) { sdev_printk(KERN_INFO, sdev, "scsi scan: %d byte inquiry failed. " "Consider BLIST_INQUIRY_36 for this device\n", try_inquiry_len); /* If this pass failed, the third pass goes back and transfers * the same amount as we successfully got in the first pass. */ try_inquiry_len = first_inquiry_len; pass = 3; goto next_pass; } /* If the last transfer attempt got an error, assume the * peripheral doesn't exist or is dead. */ if (result) return -EIO; /* Don't report any more data than the device says is valid */ sdev->inquiry_len = min(try_inquiry_len, response_len); /* * XXX Abort if the response length is less than 36? If less than * 32, the lookup of the device flags (above) could be invalid, * and it would be possible to take an incorrect action - we do * not want to hang because of a short INQUIRY. On the flip side, * if the device is spun down or becoming ready (and so it gives a * short INQUIRY), an abort here prevents any further use of the * device, including spin up. * * On the whole, the best approach seems to be to assume the first * 36 bytes are valid no matter what the device says. That's * better than copying < 36 bytes to the inquiry-result buffer * and displaying garbage for the Vendor, Product, or Revision * strings. */ if (sdev->inquiry_len < 36) { if (!sdev->host->short_inquiry) { shost_printk(KERN_INFO, sdev->host, "scsi scan: INQUIRY result too short (%d)," " using 36\n", sdev->inquiry_len); sdev->host->short_inquiry = 1; } sdev->inquiry_len = 36; } /* * Related to the above issue: * * XXX Devices (disk or all?) should be sent a TEST UNIT READY, * and if not ready, sent a START_STOP to start (maybe spin up) and * then send the INQUIRY again, since the INQUIRY can change after * a device is initialized. * * Ideally, start a device if explicitly asked to do so. This * assumes that a device is spun up on power on, spun down on * request, and then spun up on request. */ /* * The scanning code needs to know the scsi_level, even if no * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so * non-zero LUNs can be scanned. */ sdev->scsi_level = inq_result[2] & 0x07; if (sdev->scsi_level >= 2 || (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1)) sdev->scsi_level++; sdev->sdev_target->scsi_level = sdev->scsi_level; /* * If SCSI-2 or lower, and if the transport requires it, * store the LUN value in CDB[1]. */ sdev->lun_in_cdb = 0; if (sdev->scsi_level <= SCSI_2 && sdev->scsi_level != SCSI_UNKNOWN && !sdev->host->no_scsi2_lun_in_cdb) sdev->lun_in_cdb = 1; return 0; } /** * scsi_add_lun - allocate and fully initialze a scsi_device * @sdev: holds information to be stored in the new scsi_device * @inq_result: holds the result of a previous INQUIRY to the LUN * @bflags: black/white list flag * @async: 1 if this device is being scanned asynchronously * * Description: * Initialize the scsi_device @sdev. Optionally set fields based * on values in *@bflags. * * Return: * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized **/ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, blist_flags_t *bflags, int async) { int ret; /* * XXX do not save the inquiry, since it can change underneath us, * save just vendor/model/rev. * * Rather than save it and have an ioctl that retrieves the saved * value, have an ioctl that executes the same INQUIRY code used * in scsi_probe_lun, let user level programs doing INQUIRY * scanning run at their own risk, or supply a user level program * that can correctly scan. */ /* * Copy at least 36 bytes of INQUIRY data, so that we don't * dereference unallocated memory when accessing the Vendor, * Product, and Revision strings. Badly behaved devices may set * the INQUIRY Additional Length byte to a small value, indicating * these strings are invalid, but often they contain plausible data * nonetheless. It doesn't matter if the device sent < 36 bytes * total, since scsi_probe_lun() initializes inq_result with 0s. */ sdev->inquiry = kmemdup(inq_result, max_t(size_t, sdev->inquiry_len, 36), GFP_KERNEL); if (sdev->inquiry == NULL) return SCSI_SCAN_NO_RESPONSE; sdev->vendor = (char *) (sdev->inquiry + 8); sdev->model = (char *) (sdev->inquiry + 16); sdev->rev = (char *) (sdev->inquiry + 32); if (strncmp(sdev->vendor, "ATA ", 8) == 0) { /* * sata emulation layer device. This is a hack to work around * the SATL power management specifications which state that * when the SATL detects the device has gone into standby * mode, it shall respond with NOT READY. */ sdev->allow_restart = 1; } if (*bflags & BLIST_ISROM) { sdev->type = TYPE_ROM; sdev->removable = 1; } else { sdev->type = (inq_result[0] & 0x1f); sdev->removable = (inq_result[1] & 0x80) >> 7; /* * some devices may respond with wrong type for * well-known logical units. Force well-known type * to enumerate them correctly. */ if (scsi_is_wlun(sdev->lun) && sdev->type != TYPE_WLUN) { sdev_printk(KERN_WARNING, sdev, "%s: correcting incorrect peripheral device type 0x%x for W-LUN 0x%16xhN\n", __func__, sdev->type, (unsigned int)sdev->lun); sdev->type = TYPE_WLUN; } } if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { /* RBC and MMC devices can return SCSI-3 compliance and yet * still not support REPORT LUNS, so make them act as * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is * specifically set */ if ((*bflags & BLIST_REPORTLUN2) == 0) *bflags |= BLIST_NOREPORTLUN; } /* * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI * spec says: The device server is capable of supporting the * specified peripheral device type on this logical unit. However, * the physical device is not currently connected to this logical * unit. * * The above is vague, as it implies that we could treat 001 and * 011 the same. Stay compatible with previous code, and create a * scsi_device for a PQ of 1 * * Don't set the device offline here; rather let the upper * level drivers eval the PQ to decide whether they should * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check. */ sdev->inq_periph_qual = (inq_result[0] >> 5) & 7; sdev->lockable = sdev->removable; sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2); if (sdev->scsi_level >= SCSI_3 || (sdev->inquiry_len > 56 && inq_result[56] & 0x04)) sdev->ppr = 1; if (inq_result[7] & 0x60) sdev->wdtr = 1; if (inq_result[7] & 0x10) sdev->sdtr = 1; sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d " "ANSI: %d%s\n", scsi_device_type(sdev->type), sdev->vendor, sdev->model, sdev->rev, sdev->inq_periph_qual, inq_result[2] & 0x07, (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && !(*bflags & BLIST_NOTQ)) { sdev->tagged_supported = 1; sdev->simple_tags = 1; } /* * Some devices (Texel CD ROM drives) have handshaking problems * when used with the Seagate controllers. borken is initialized * to 1, and then set it to 0 here. */ if ((*bflags & BLIST_BORKEN) == 0) sdev->borken = 0; if (*bflags & BLIST_NO_ULD_ATTACH) sdev->no_uld_attach = 1; /* * Apparently some really broken devices (contrary to the SCSI * standards) need to be selected without asserting ATN */ if (*bflags & BLIST_SELECT_NO_ATN) sdev->select_no_atn = 1; /* * Maximum 512 sector transfer length * broken RA4x00 Compaq Disk Array */ if (*bflags & BLIST_MAX_512) blk_queue_max_hw_sectors(sdev->request_queue, 512); /* * Max 1024 sector transfer length for targets that report incorrect * max/optimal lengths and relied on the old block layer safe default */ else if (*bflags & BLIST_MAX_1024) blk_queue_max_hw_sectors(sdev->request_queue, 1024); /* * Some devices may not want to have a start command automatically * issued when a device is added. */ if (*bflags & BLIST_NOSTARTONADD) sdev->no_start_on_add = 1; if (*bflags & BLIST_SINGLELUN) scsi_target(sdev)->single_lun = 1; sdev->use_10_for_rw = 1; /* some devices don't like REPORT SUPPORTED OPERATION CODES * and will simply timeout causing sd_mod init to take a very * very long time */ if (*bflags & BLIST_NO_RSOC) sdev->no_report_opcodes = 1; /* set the device running here so that slave configure * may do I/O */ mutex_lock(&sdev->state_mutex); ret = scsi_device_set_state(sdev, SDEV_RUNNING); if (ret) ret = scsi_device_set_state(sdev, SDEV_BLOCK); mutex_unlock(&sdev->state_mutex); if (ret) { sdev_printk(KERN_ERR, sdev, "in wrong state %s to complete scan\n", scsi_device_state_name(sdev->sdev_state)); return SCSI_SCAN_NO_RESPONSE; } if (*bflags & BLIST_NOT_LOCKABLE) sdev->lockable = 0; if (*bflags & BLIST_RETRY_HWERROR) sdev->retry_hwerror = 1; if (*bflags & BLIST_NO_DIF) sdev->no_dif = 1; if (*bflags & BLIST_UNMAP_LIMIT_WS) sdev->unmap_limit_for_ws = 1; if (*bflags & BLIST_IGN_MEDIA_CHANGE) sdev->ignore_media_change = 1; sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT; if (*bflags & BLIST_TRY_VPD_PAGES) sdev->try_vpd_pages = 1; else if (*bflags & BLIST_SKIP_VPD_PAGES) sdev->skip_vpd_pages = 1; transport_configure_device(&sdev->sdev_gendev); if (sdev->host->hostt->slave_configure) { ret = sdev->host->hostt->slave_configure(sdev); if (ret) { /* * if LLDD reports slave not present, don't clutter * console with alloc failure messages */ if (ret != -ENXIO) { sdev_printk(KERN_ERR, sdev, "failed to configure device\n"); } return SCSI_SCAN_NO_RESPONSE; } /* * The queue_depth is often changed in ->slave_configure. * Set up budget map again since memory consumption of * the map depends on actual queue depth. */ scsi_realloc_sdev_budget_map(sdev, sdev->queue_depth); } if (sdev->scsi_level >= SCSI_3) scsi_attach_vpd(sdev); sdev->max_queue_depth = sdev->queue_depth; WARN_ON_ONCE(sdev->max_queue_depth > sdev->budget_map.depth); sdev->sdev_bflags = *bflags; /* * Ok, the device is now all set up, we can * register it and tell the rest of the kernel * about it. */ if (!async && scsi_sysfs_add_sdev(sdev) != 0) return SCSI_SCAN_NO_RESPONSE; return SCSI_SCAN_LUN_PRESENT; } #ifdef CONFIG_SCSI_LOGGING /** * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace * @buf: Output buffer with at least end-first+1 bytes of space * @inq: Inquiry buffer (input) * @first: Offset of string into inq * @end: Index after last character in inq */ static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq, unsigned first, unsigned end) { unsigned term = 0, idx; for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) { if (inq[idx+first] > ' ') { buf[idx] = inq[idx+first]; term = idx+1; } else { buf[idx] = ' '; } } buf[term] = 0; return buf; } #endif /** * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it * @starget: pointer to target device structure * @lun: LUN of target device * @bflagsp: store bflags here if not NULL * @sdevp: probe the LUN corresponding to this scsi_device * @rescan: if not equal to SCSI_SCAN_INITIAL skip some code only * needed on first scan * @hostdata: passed to scsi_alloc_sdev() * * Description: * Call scsi_probe_lun, if a LUN with an attached device is found, * allocate and set it up by calling scsi_add_lun. * * Return: * * - SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device * - SCSI_SCAN_TARGET_PRESENT: target responded, but no device is * attached at the LUN * - SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized **/ static int scsi_probe_and_add_lun(struct scsi_target *starget, u64 lun, blist_flags_t *bflagsp, struct scsi_device **sdevp, enum scsi_scan_mode rescan, void *hostdata) { struct scsi_device *sdev; unsigned char *result; blist_flags_t bflags; int res = SCSI_SCAN_NO_RESPONSE, result_len = 256; struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); /* * The rescan flag is used as an optimization, the first scan of a * host adapter calls into here with rescan == 0. */ sdev = scsi_device_lookup_by_target(starget, lun); if (sdev) { if (rescan != SCSI_SCAN_INITIAL || !scsi_device_created(sdev)) { SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, "scsi scan: device exists on %s\n", dev_name(&sdev->sdev_gendev))); if (sdevp) *sdevp = sdev; else scsi_device_put(sdev); if (bflagsp) *bflagsp = scsi_get_device_flags(sdev, sdev->vendor, sdev->model); return SCSI_SCAN_LUN_PRESENT; } scsi_device_put(sdev); } else sdev = scsi_alloc_sdev(starget, lun, hostdata); if (!sdev) goto out; result = kmalloc(result_len, GFP_KERNEL); if (!result) goto out_free_sdev; if (scsi_probe_lun(sdev, result, result_len, &bflags)) goto out_free_result; if (bflagsp) *bflagsp = bflags; /* * result contains valid SCSI INQUIRY data. */ if ((result[0] >> 5) == 3) { /* * For a Peripheral qualifier 3 (011b), the SCSI * spec says: The device server is not capable of * supporting a physical device on this logical * unit. * * For disks, this implies that there is no * logical disk configured at sdev->lun, but there * is a target id responding. */ SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:" " peripheral qualifier of 3, device not" " added\n")) if (lun == 0) { SCSI_LOG_SCAN_BUS(1, { unsigned char vend[9]; unsigned char mod[17]; sdev_printk(KERN_INFO, sdev, "scsi scan: consider passing scsi_mod." "dev_flags=%s:%s:0x240 or 0x1000240\n", scsi_inq_str(vend, result, 8, 16), scsi_inq_str(mod, result, 16, 32)); }); } res = SCSI_SCAN_TARGET_PRESENT; goto out_free_result; } /* * Some targets may set slight variations of PQ and PDT to signal * that no LUN is present, so don't add sdev in these cases. * Two specific examples are: * 1) NetApp targets: return PQ=1, PDT=0x1f * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved" * in the UFI 1.0 spec (we cannot rely on reserved bits). * * References: * 1) SCSI SPC-3, pp. 145-146 * PQ=1: "A peripheral device having the specified peripheral * device type is not connected to this logical unit. However, the * device server is capable of supporting the specified peripheral * device type on this logical unit." * PDT=0x1f: "Unknown or no device type" * 2) USB UFI 1.0, p. 20 * PDT=00h Direct-access device (floppy) * PDT=1Fh none (no FDD connected to the requested logical unit) */ if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) && (result[0] & 0x1f) == 0x1f && !scsi_is_wlun(lun)) { SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev, "scsi scan: peripheral device type" " of 31, no device added\n")); res = SCSI_SCAN_TARGET_PRESENT; goto out_free_result; } res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); if (res == SCSI_SCAN_LUN_PRESENT) { if (bflags & BLIST_KEY) { sdev->lockable = 0; scsi_unlock_floptical(sdev, result); } } out_free_result: kfree(result); out_free_sdev: if (res == SCSI_SCAN_LUN_PRESENT) { if (sdevp) { if (scsi_device_get(sdev) == 0) { *sdevp = sdev; } else { __scsi_remove_device(sdev); res = SCSI_SCAN_NO_RESPONSE; } } } else __scsi_remove_device(sdev); out: return res; } /** * scsi_sequential_lun_scan - sequentially scan a SCSI target * @starget: pointer to target structure to scan * @bflags: black/white list flag for LUN 0 * @scsi_level: Which version of the standard does this device adhere to * @rescan: passed to scsi_probe_add_lun() * * Description: * Generally, scan from LUN 1 (LUN 0 is assumed to already have been * scanned) to some maximum lun until a LUN is found with no device * attached. Use the bflags to figure out any oddities. * * Modifies sdevscan->lun. **/ static void scsi_sequential_lun_scan(struct scsi_target *starget, blist_flags_t bflags, int scsi_level, enum scsi_scan_mode rescan) { uint max_dev_lun; u64 sparse_lun, lun; struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); SCSI_LOG_SCAN_BUS(3, starget_printk(KERN_INFO, starget, "scsi scan: Sequential scan\n")); max_dev_lun = min(max_scsi_luns, shost->max_lun); /* * If this device is known to support sparse multiple units, * override the other settings, and scan all of them. Normally, * SCSI-3 devices should be scanned via the REPORT LUNS. */ if (bflags & BLIST_SPARSELUN) { max_dev_lun = shost->max_lun; sparse_lun = 1; } else sparse_lun = 0; /* * If less than SCSI_1_CCS, and no special lun scanning, stop * scanning; this matches 2.4 behaviour, but could just be a bug * (to continue scanning a SCSI_1_CCS device). * * This test is broken. We might not have any device on lun0 for * a sparselun device, and if that's the case then how would we * know the real scsi_level, eh? It might make sense to just not * scan any SCSI_1 device for non-0 luns, but that check would best * go into scsi_alloc_sdev() and just have it return null when asked * to alloc an sdev for lun > 0 on an already found SCSI_1 device. * if ((sdevscan->scsi_level < SCSI_1_CCS) && ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN)) == 0)) return; */ /* * If this device is known to support multiple units, override * the other settings, and scan all of them. */ if (bflags & BLIST_FORCELUN) max_dev_lun = shost->max_lun; /* * REGAL CDC-4X: avoid hang after LUN 4 */ if (bflags & BLIST_MAX5LUN) max_dev_lun = min(5U, max_dev_lun); /* * Do not scan SCSI-2 or lower device past LUN 7, unless * BLIST_LARGELUN. */ if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN)) max_dev_lun = min(8U, max_dev_lun); else max_dev_lun = min(256U, max_dev_lun); /* * We have already scanned LUN 0, so start at LUN 1. Keep scanning * until we reach the max, or no LUN is found and we are not * sparse_lun. */ for (lun = 1; lun < max_dev_lun; ++lun) if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL) != SCSI_SCAN_LUN_PRESENT) && !sparse_lun) return; } /** * scsi_report_lun_scan - Scan using SCSI REPORT LUN results * @starget: which target * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN * @rescan: nonzero if we can skip code only needed on first scan * * Description: * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command. * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun. * * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8 * LUNs even if it's older than SCSI-3. * If BLIST_NOREPORTLUN is set, return 1 always. * If BLIST_NOLUN is set, return 0 always. * If starget->no_report_luns is set, return 1 always. * * Return: * 0: scan completed (or no memory, so further scanning is futile) * 1: could not scan with REPORT LUN **/ static int scsi_report_lun_scan(struct scsi_target *starget, blist_flags_t bflags, enum scsi_scan_mode rescan) { unsigned char scsi_cmd[MAX_COMMAND_SIZE]; unsigned int length; u64 lun; unsigned int num_luns; unsigned int retries; int result; struct scsi_lun *lunp, *lun_data; struct scsi_sense_hdr sshdr; struct scsi_device *sdev; struct Scsi_Host *shost = dev_to_shost(&starget->dev); int ret = 0; /* * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set. * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does * support more than 8 LUNs. * Don't attempt if the target doesn't support REPORT LUNS. */ if (bflags & BLIST_NOREPORTLUN) return 1; if (starget->scsi_level < SCSI_2 && starget->scsi_level != SCSI_UNKNOWN) return 1; if (starget->scsi_level < SCSI_3 && (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) return 1; if (bflags & BLIST_NOLUN) return 0; if (starget->no_report_luns) return 1; if (!(sdev = scsi_device_lookup_by_target(starget, 0))) { sdev = scsi_alloc_sdev(starget, 0, NULL); if (!sdev) return 0; if (scsi_device_get(sdev)) { __scsi_remove_device(sdev); return 0; } } /* * Allocate enough to hold the header (the same size as one scsi_lun) * plus the number of luns we are requesting. 511 was the default * value of the now removed max_report_luns parameter. */ length = (511 + 1) * sizeof(struct scsi_lun); retry: lun_data = kmalloc(length, GFP_KERNEL); if (!lun_data) { printk(ALLOC_FAILURE_MSG, __func__); goto out; } scsi_cmd[0] = REPORT_LUNS; /* * bytes 1 - 5: reserved, set to zero. */ memset(&scsi_cmd[1], 0, 5); /* * bytes 6 - 9: length of the command. */ put_unaligned_be32(length, &scsi_cmd[6]); scsi_cmd[10] = 0; /* reserved */ scsi_cmd[11] = 0; /* control */ /* * We can get a UNIT ATTENTION, for example a power on/reset, so * retry a few times (like sd.c does for TEST UNIT READY). * Experience shows some combinations of adapter/devices get at * least two power on/resets. * * Illegal requests (for devices that do not support REPORT LUNS) * should come through as a check condition, and will not generate * a retry. */ for (retries = 0; retries < 3; retries++) { SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, "scsi scan: Sending REPORT LUNS to (try %d)\n", retries)); result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, lun_data, length, &sshdr, SCSI_REPORT_LUNS_TIMEOUT, 3, NULL); SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, "scsi scan: REPORT LUNS" " %s (try %d) result 0x%x\n", result ? "failed" : "successful", retries, result)); if (result == 0) break; else if (scsi_sense_valid(&sshdr)) { if (sshdr.sense_key != UNIT_ATTENTION) break; } } if (result) { /* * The device probably does not support a REPORT LUN command */ ret = 1; goto out_err; } /* * Get the length from the first four bytes of lun_data. */ if (get_unaligned_be32(lun_data->scsi_lun) + sizeof(struct scsi_lun) > length) { length = get_unaligned_be32(lun_data->scsi_lun) + sizeof(struct scsi_lun); kfree(lun_data); goto retry; } length = get_unaligned_be32(lun_data->scsi_lun); num_luns = (length / sizeof(struct scsi_lun)); SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev, "scsi scan: REPORT LUN scan\n")); /* * Scan the luns in lun_data. The entry at offset 0 is really * the header, so start at 1 and go up to and including num_luns. */ for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) { lun = scsilun_to_int(lunp); if (lun > sdev->host->max_lun) { sdev_printk(KERN_WARNING, sdev, "lun%llu has a LUN larger than" " allowed by the host adapter\n", lun); } else { int res; res = scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); if (res == SCSI_SCAN_NO_RESPONSE) { /* * Got some results, but now none, abort. */ sdev_printk(KERN_ERR, sdev, "Unexpected response" " from lun %llu while scanning, scan" " aborted\n", (unsigned long long)lun); break; } } } out_err: kfree(lun_data); out: if (scsi_device_created(sdev)) /* * the sdev we used didn't appear in the report luns scan */ __scsi_remove_device(sdev); scsi_device_put(sdev); return ret; } struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, uint id, u64 lun, void *hostdata) { struct scsi_device *sdev = ERR_PTR(-ENODEV); struct device *parent = &shost->shost_gendev; struct scsi_target *starget; if (strncmp(scsi_scan_type, "none", 4) == 0) return ERR_PTR(-ENODEV); starget = scsi_alloc_target(parent, channel, id); if (!starget) return ERR_PTR(-ENOMEM); scsi_autopm_get_target(starget); mutex_lock(&shost->scan_mutex); if (!shost->async_scan) scsi_complete_async_scans(); if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); scsi_autopm_put_host(shost); } mutex_unlock(&shost->scan_mutex); scsi_autopm_put_target(starget); /* * paired with scsi_alloc_target(). Target will be destroyed unless * scsi_probe_and_add_lun made an underlying device visible */ scsi_target_reap(starget); put_device(&starget->dev); return sdev; } EXPORT_SYMBOL(__scsi_add_device); int scsi_add_device(struct Scsi_Host *host, uint channel, uint target, u64 lun) { struct scsi_device *sdev = __scsi_add_device(host, channel, target, lun, NULL); if (IS_ERR(sdev)) return PTR_ERR(sdev); scsi_device_put(sdev); return 0; } EXPORT_SYMBOL(scsi_add_device); void scsi_rescan_device(struct device *dev) { struct scsi_device *sdev = to_scsi_device(dev); device_lock(dev); scsi_attach_vpd(sdev); if (sdev->handler && sdev->handler->rescan) sdev->handler->rescan(sdev); if (dev->driver && try_module_get(dev->driver->owner)) { struct scsi_driver *drv = to_scsi_driver(dev->driver); if (drv->rescan) drv->rescan(dev); module_put(dev->driver->owner); } device_unlock(dev); } EXPORT_SYMBOL(scsi_rescan_device); static void __scsi_scan_target(struct device *parent, unsigned int channel, unsigned int id, u64 lun, enum scsi_scan_mode rescan) { struct Scsi_Host *shost = dev_to_shost(parent); blist_flags_t bflags = 0; int res; struct scsi_target *starget; if (shost->this_id == id) /* * Don't scan the host adapter */ return; starget = scsi_alloc_target(parent, channel, id); if (!starget) return; scsi_autopm_get_target(starget); if (lun != SCAN_WILD_CARD) { /* * Scan for a specific host/chan/id/lun. */ scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL); goto out_reap; } /* * Scan LUN 0, if there is some response, scan further. Ideally, we * would not configure LUN 0 until all LUNs are scanned. */ res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL); if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) { if (scsi_report_lun_scan(starget, bflags, rescan) != 0) /* * The REPORT LUN did not scan the target, * do a sequential scan. */ scsi_sequential_lun_scan(starget, bflags, starget->scsi_level, rescan); } out_reap: scsi_autopm_put_target(starget); /* * paired with scsi_alloc_target(): determine if the target has * any children at all and if not, nuke it */ scsi_target_reap(starget); put_device(&starget->dev); } /** * scsi_scan_target - scan a target id, possibly including all LUNs on the target. * @parent: host to scan * @channel: channel to scan * @id: target id to scan * @lun: Specific LUN to scan or SCAN_WILD_CARD * @rescan: passed to LUN scanning routines; SCSI_SCAN_INITIAL for * no rescan, SCSI_SCAN_RESCAN to rescan existing LUNs, * and SCSI_SCAN_MANUAL to force scanning even if * 'scan=manual' is set. * * Description: * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0, * and possibly all LUNs on the target id. * * First try a REPORT LUN scan, if that does not scan the target, do a * sequential scan of LUNs on the target id. **/ void scsi_scan_target(struct device *parent, unsigned int channel, unsigned int id, u64 lun, enum scsi_scan_mode rescan) { struct Scsi_Host *shost = dev_to_shost(parent); if (strncmp(scsi_scan_type, "none", 4) == 0) return; if (rescan != SCSI_SCAN_MANUAL && strncmp(scsi_scan_type, "manual", 6) == 0) return; mutex_lock(&shost->scan_mutex); if (!shost->async_scan) scsi_complete_async_scans(); if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { __scsi_scan_target(parent, channel, id, lun, rescan); scsi_autopm_put_host(shost); } mutex_unlock(&shost->scan_mutex); } EXPORT_SYMBOL(scsi_scan_target); static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, unsigned int id, u64 lun, enum scsi_scan_mode rescan) { uint order_id; if (id == SCAN_WILD_CARD) for (id = 0; id < shost->max_id; ++id) { /* * XXX adapter drivers when possible (FCP, iSCSI) * could modify max_id to match the current max, * not the absolute max. * * XXX add a shost id iterator, so for example, * the FC ID can be the same as a target id * without a huge overhead of sparse id's. */ if (shost->reverse_ordering) /* * Scan from high to low id. */ order_id = shost->max_id - id - 1; else order_id = id; __scsi_scan_target(&shost->shost_gendev, channel, order_id, lun, rescan); } else __scsi_scan_target(&shost->shost_gendev, channel, id, lun, rescan); } int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, unsigned int id, u64 lun, enum scsi_scan_mode rescan) { SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost, "%s: <%u:%u:%llu>\n", __func__, channel, id, lun)); if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) || ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) || ((lun != SCAN_WILD_CARD) && (lun >= shost->max_lun))) return -EINVAL; mutex_lock(&shost->scan_mutex); if (!shost->async_scan) scsi_complete_async_scans(); if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) { if (channel == SCAN_WILD_CARD) for (channel = 0; channel <= shost->max_channel; channel++) scsi_scan_channel(shost, channel, id, lun, rescan); else scsi_scan_channel(shost, channel, id, lun, rescan); scsi_autopm_put_host(shost); } mutex_unlock(&shost->scan_mutex); return 0; } static void scsi_sysfs_add_devices(struct Scsi_Host *shost) { struct scsi_device *sdev; shost_for_each_device(sdev, shost) { /* target removed before the device could be added */ if (sdev->sdev_state == SDEV_DEL) continue; /* If device is already visible, skip adding it to sysfs */ if (sdev->is_visible) continue; if (!scsi_host_scan_allowed(shost) || scsi_sysfs_add_sdev(sdev) != 0) __scsi_remove_device(sdev); } } /** * scsi_prep_async_scan - prepare for an async scan * @shost: the host which will be scanned * Returns: a cookie to be passed to scsi_finish_async_scan() * * Tells the midlayer this host is going to do an asynchronous scan. * It reserves the host's position in the scanning list and ensures * that other asynchronous scans started after this one won't affect the * ordering of the discovered devices. */ static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) { struct async_scan_data *data = NULL; unsigned long flags; if (strncmp(scsi_scan_type, "sync", 4) == 0) return NULL; mutex_lock(&shost->scan_mutex); if (shost->async_scan) { shost_printk(KERN_DEBUG, shost, "%s called twice\n", __func__); goto err; } data = kmalloc(sizeof(*data), GFP_KERNEL); if (!data) goto err; data->shost = scsi_host_get(shost); if (!data->shost) goto err; init_completion(&data->prev_finished); spin_lock_irqsave(shost->host_lock, flags); shost->async_scan = 1; spin_unlock_irqrestore(shost->host_lock, flags); mutex_unlock(&shost->scan_mutex); spin_lock(&async_scan_lock); if (list_empty(&scanning_hosts)) complete(&data->prev_finished); list_add_tail(&data->list, &scanning_hosts); spin_unlock(&async_scan_lock); return data; err: mutex_unlock(&shost->scan_mutex); kfree(data); return NULL; } /** * scsi_finish_async_scan - asynchronous scan has finished * @data: cookie returned from earlier call to scsi_prep_async_scan() * * All the devices currently attached to this host have been found. * This function announces all the devices it has found to the rest * of the system. */ static void scsi_finish_async_scan(struct async_scan_data *data) { struct Scsi_Host *shost; unsigned long flags; if (!data) return; shost = data->shost; mutex_lock(&shost->scan_mutex); if (!shost->async_scan) { shost_printk(KERN_INFO, shost, "%s called twice\n", __func__); dump_stack(); mutex_unlock(&shost->scan_mutex); return; } wait_for_completion(&data->prev_finished); scsi_sysfs_add_devices(shost); spin_lock_irqsave(shost->host_lock, flags); shost->async_scan = 0; spin_unlock_irqrestore(shost->host_lock, flags); mutex_unlock(&shost->scan_mutex); spin_lock(&async_scan_lock); list_del(&data->list); if (!list_empty(&scanning_hosts)) { struct async_scan_data *next = list_entry(scanning_hosts.next, struct async_scan_data, list); complete(&next->prev_finished); } spin_unlock(&async_scan_lock); scsi_autopm_put_host(shost); scsi_host_put(shost); kfree(data); } static void do_scsi_scan_host(struct Scsi_Host *shost) { if (shost->hostt->scan_finished) { unsigned long start = jiffies; if (shost->hostt->scan_start) shost->hostt->scan_start(shost); while (!shost->hostt->scan_finished(shost, jiffies - start)) msleep(10); } else { scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, SCAN_WILD_CARD, 0); } } static void do_scan_async(void *_data, async_cookie_t c) { struct async_scan_data *data = _data; struct Scsi_Host *shost = data->shost; do_scsi_scan_host(shost); scsi_finish_async_scan(data); } /** * scsi_scan_host - scan the given adapter * @shost: adapter to scan **/ void scsi_scan_host(struct Scsi_Host *shost) { struct async_scan_data *data; if (strncmp(scsi_scan_type, "none", 4) == 0 || strncmp(scsi_scan_type, "manual", 6) == 0) return; if (scsi_autopm_get_host(shost) < 0) return; data = scsi_prep_async_scan(shost); if (!data) { do_scsi_scan_host(shost); scsi_autopm_put_host(shost); return; } /* register with the async subsystem so wait_for_device_probe() * will flush this work */ async_schedule(do_scan_async, data); /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */ } EXPORT_SYMBOL(scsi_scan_host); void scsi_forget_host(struct Scsi_Host *shost) { struct scsi_device *sdev; unsigned long flags; restart: spin_lock_irqsave(shost->host_lock, flags); list_for_each_entry(sdev, &shost->__devices, siblings) { if (sdev->sdev_state == SDEV_DEL) continue; spin_unlock_irqrestore(shost->host_lock, flags); __scsi_remove_device(sdev); goto restart; } spin_unlock_irqrestore(shost->host_lock, flags); } /** * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself * @shost: Host that needs a scsi_device * * Lock status: None assumed. * * Returns: The scsi_device or NULL * * Notes: * Attach a single scsi_device to the Scsi_Host - this should * be made to look like a "pseudo-device" that points to the * HA itself. * * Note - this device is not accessible from any high-level * drivers (including generics), which is probably not * optimal. We can add hooks later to attach. */ struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost) { struct scsi_device *sdev = NULL; struct scsi_target *starget; mutex_lock(&shost->scan_mutex); if (!scsi_host_scan_allowed(shost)) goto out; starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); if (!starget) goto out; sdev = scsi_alloc_sdev(starget, 0, NULL); if (sdev) sdev->borken = 0; else scsi_target_reap(starget); put_device(&starget->dev); out: mutex_unlock(&shost->scan_mutex); return sdev; } EXPORT_SYMBOL(scsi_get_host_dev); /** * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself * @sdev: Host device to be freed * * Lock status: None assumed. * * Returns: Nothing */ void scsi_free_host_dev(struct scsi_device *sdev) { BUG_ON(sdev->id != sdev->host->this_id); __scsi_remove_device(sdev); } EXPORT_SYMBOL(scsi_free_host_dev);