/* * 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 "scsi.h" #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" /* * Prefix values for the SCSI id's (stored in driverfs 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 char *scsi_null_device_strs = "nullnullnullnull"; #define MAX_SCSI_LUNS 512 #ifdef CONFIG_SCSI_MULTI_LUN static unsigned int max_scsi_luns = MAX_SCSI_LUNS; #else static unsigned int max_scsi_luns = 1; #endif module_param_named(max_luns, max_scsi_luns, int, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(max_luns, "last scsi LUN (should be between 1 and 2^32-1)"); #ifdef CONFIG_SCSI_REPORT_LUNS /* * max_scsi_report_luns: the maximum number of LUNS that will be * returned from the REPORT LUNS command. 8 times this value must * be allocated. In theory this could be up to an 8 byte value, but * in practice, the maximum number of LUNs suppored by any device * is about 16k. */ static unsigned int max_scsi_report_luns = 128; module_param_named(max_report_luns, max_scsi_report_luns, int, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(max_report_luns, "REPORT LUNS maximum number of LUNS received (should be" " between 1 and 16384)"); #endif /** * scsi_unlock_floptical - unlock device via a special MODE SENSE command * @sreq: used to send the command * @result: area to store the result of the MODE SENSE * * Description: * Send a vendor specific MODE SENSE (not a MODE SELECT) command using * @sreq to unlock a device, storing the (unused) results into result. * Called for BLIST_KEY devices. **/ static void scsi_unlock_floptical(struct scsi_request *sreq, unsigned char *result) { unsigned char scsi_cmd[MAX_COMMAND_SIZE]; printk(KERN_NOTICE "scsi: 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; sreq->sr_cmd_len = 0; sreq->sr_data_direction = DMA_FROM_DEVICE; scsi_wait_req(sreq, scsi_cmd, result, 0x2a /* size */, SCSI_TIMEOUT, 3); } /** * print_inquiry - printk the inquiry information * @inq_result: printk this SCSI INQUIRY * * Description: * printk the vendor, model, and other information found in the * INQUIRY data in @inq_result. * * Notes: * Remove this, and replace with a hotplug event that logs any * relevant information. **/ static void print_inquiry(unsigned char *inq_result) { int i; printk(KERN_NOTICE " Vendor: "); for (i = 8; i < 16; i++) if (inq_result[i] >= 0x20 && i < inq_result[4] + 5) printk("%c", inq_result[i]); else printk(" "); printk(" Model: "); for (i = 16; i < 32; i++) if (inq_result[i] >= 0x20 && i < inq_result[4] + 5) printk("%c", inq_result[i]); else printk(" "); printk(" Rev: "); for (i = 32; i < 36; i++) if (inq_result[i] >= 0x20 && i < inq_result[4] + 5) printk("%c", inq_result[i]); else printk(" "); printk("\n"); i = inq_result[0] & 0x1f; printk(KERN_NOTICE " Type: %s ", i < MAX_SCSI_DEVICE_CODE ? scsi_device_types[i] : "Unknown "); printk(" ANSI SCSI revision: %02x", inq_result[2] & 0x07); if ((inq_result[2] & 0x07) == 1 && (inq_result[3] & 0x0f) == 1) printk(" CCS\n"); else printk("\n"); } /** * scsi_alloc_sdev - allocate and setup a scsi_Device * * 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_Host *shost, uint channel, uint id, uint lun) { struct scsi_device *sdev, *device; unsigned long flags; sdev = kmalloc(sizeof(*sdev) + shost->transportt->size, GFP_ATOMIC); if (!sdev) goto out; memset(sdev, 0, sizeof(*sdev)); sdev->vendor = scsi_null_device_strs; sdev->model = scsi_null_device_strs; sdev->rev = scsi_null_device_strs; sdev->host = shost; sdev->id = id; sdev->lun = lun; sdev->channel = channel; sdev->sdev_state = SDEV_CREATED; INIT_LIST_HEAD(&sdev->siblings); INIT_LIST_HEAD(&sdev->same_target_siblings); INIT_LIST_HEAD(&sdev->cmd_list); INIT_LIST_HEAD(&sdev->starved_entry); spin_lock_init(&sdev->list_lock); /* * 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; spin_lock_init(&sdev->sdev_lock); sdev->request_queue = scsi_alloc_queue(sdev); if (!sdev->request_queue) goto out_free_dev; sdev->request_queue->queuedata = sdev; scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); if (shost->hostt->slave_alloc) { if (shost->hostt->slave_alloc(sdev)) goto out_free_queue; } if (shost->transportt->setup) { if (shost->transportt->setup(sdev)) goto out_cleanup_slave; } if (get_device(&sdev->host->shost_gendev)) { device_initialize(&sdev->sdev_gendev); sdev->sdev_gendev.parent = &sdev->host->shost_gendev; sdev->sdev_gendev.bus = &scsi_bus_type; sdev->sdev_gendev.release = scsi_device_dev_release; sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d", sdev->host->host_no, sdev->channel, sdev->id, sdev->lun); class_device_initialize(&sdev->sdev_classdev); sdev->sdev_classdev.dev = &sdev->sdev_gendev; sdev->sdev_classdev.class = &sdev_class; snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE, "%d:%d:%d:%d", sdev->host->host_no, sdev->channel, sdev->id, sdev->lun); class_device_initialize(&sdev->transport_classdev); sdev->transport_classdev.dev = &sdev->sdev_gendev; sdev->transport_classdev.class = sdev->host->transportt->class; snprintf(sdev->transport_classdev.class_id, BUS_ID_SIZE, "%d:%d:%d:%d", sdev->host->host_no, sdev->channel, sdev->id, sdev->lun); } else goto out_cleanup_transport; /* * If there are any same target siblings, add this to the * sibling list */ spin_lock_irqsave(shost->host_lock, flags); list_for_each_entry(device, &shost->__devices, siblings) { if (device->id == sdev->id && device->channel == sdev->channel) { list_add_tail(&sdev->same_target_siblings, &device->same_target_siblings); sdev->scsi_level = device->scsi_level; break; } } /* * If there wasn't another lun already configured at this * target, then default this device to SCSI_2 until we * know better */ if (!sdev->scsi_level) sdev->scsi_level = SCSI_2; list_add_tail(&sdev->siblings, &shost->__devices); spin_unlock_irqrestore(shost->host_lock, flags); return sdev; out_cleanup_transport: if (shost->transportt->cleanup) shost->transportt->cleanup(sdev); out_cleanup_slave: if (shost->hostt->slave_destroy) shost->hostt->slave_destroy(sdev); out_free_queue: scsi_free_queue(sdev->request_queue); out_free_dev: kfree(sdev); out: printk(ALLOC_FAILURE_MSG, __FUNCTION__); return NULL; } /** * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY * @sreq: used to send the INQUIRY * @inq_result: area to store the INQUIRY result * @bflags: store any bflags found here * * Description: * Probe the lun associated with @sreq using a standard SCSI INQUIRY; * * If the INQUIRY is successful, sreq->sr_result is zero and: the * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length * are copied to the Scsi_Device at @sreq->sr_device (sdev); * any flags value is stored in *@bflags. **/ static void scsi_probe_lun(struct scsi_request *sreq, char *inq_result, int *bflags) { struct scsi_device *sdev = sreq->sr_device; /* a bit ugly */ unsigned char scsi_cmd[MAX_COMMAND_SIZE]; int possible_inq_resp_len; *bflags = 0; repeat_inquiry: SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY to host %d" " channel %d id %d lun %d\n", sdev->host->host_no, sdev->channel, sdev->id, sdev->lun)); memset(scsi_cmd, 0, 6); scsi_cmd[0] = INQUIRY; scsi_cmd[4] = 36; /* issue conservative alloc_length */ sreq->sr_cmd_len = 0; sreq->sr_data_direction = DMA_FROM_DEVICE; memset(inq_result, 0, 36); scsi_wait_req(sreq, (void *) scsi_cmd, (void *) inq_result, 36, SCSI_TIMEOUT + 4 * HZ, 3); SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: 1st INQUIRY %s with" " code 0x%x\n", sreq->sr_result ? "failed" : "successful", sreq->sr_result)); if (sreq->sr_result) { if ((driver_byte(sreq->sr_result) & DRIVER_SENSE) != 0 && (sreq->sr_sense_buffer[2] & 0xf) == UNIT_ATTENTION && sreq->sr_sense_buffer[12] == 0x28 && sreq->sr_sense_buffer[13] == 0) { /* not-ready to ready transition - good */ /* dpg: bogus? INQUIRY never returns UNIT_ATTENTION */ } else /* * assume no peripheral if any other sort of error */ return; } /* * 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]); possible_inq_resp_len = (unsigned char) inq_result[4] + 5; if (BLIST_INQUIRY_36 & *bflags) possible_inq_resp_len = 36; else if (BLIST_INQUIRY_58 & *bflags) possible_inq_resp_len = 58; else if (possible_inq_resp_len > 255) possible_inq_resp_len = 36; /* sanity */ if (possible_inq_resp_len > 36) { /* do additional INQUIRY */ memset(scsi_cmd, 0, 6); scsi_cmd[0] = INQUIRY; scsi_cmd[4] = (unsigned char) possible_inq_resp_len; sreq->sr_cmd_len = 0; sreq->sr_data_direction = DMA_FROM_DEVICE; /* * re-zero inq_result just to be safe. */ memset(inq_result, 0, possible_inq_resp_len); scsi_wait_req(sreq, (void *) scsi_cmd, (void *) inq_result, possible_inq_resp_len, SCSI_TIMEOUT + 4 * HZ, 3); SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: 2nd INQUIRY" " %s with code 0x%x\n", sreq->sr_result ? "failed" : "successful", sreq->sr_result)); if (sreq->sr_result) { /* if the longer inquiry has failed, flag the device * as only accepting 36 byte inquiries and retry the * 36 byte inquiry */ printk(KERN_INFO "scsi scan: %d byte inquiry failed" " with code %d. Consider BLIST_INQUIRY_36 for" " this device\n", possible_inq_resp_len, sreq->sr_result); *bflags = BLIST_INQUIRY_36; goto repeat_inquiry; } /* * The INQUIRY can change, this means the length can change. */ possible_inq_resp_len = (unsigned char) inq_result[4] + 5; if (BLIST_INQUIRY_58 & *bflags) possible_inq_resp_len = 58; else if (possible_inq_resp_len > 255) possible_inq_resp_len = 36; /* sanity */ } sdev->inquiry_len = possible_inq_resp_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. * * 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++; return; } /** * scsi_add_lun - allocate and fully initialze a Scsi_Device * @sdevscan: holds information to be stored in the new Scsi_Device * @sdevnew: store the address of the newly allocated Scsi_Device * @inq_result: holds the result of a previous INQUIRY to the LUN * @bflags: black/white list flag * * Description: * Allocate and initialize a Scsi_Device matching sdevscan. Optionally * set fields based on values in *@bflags. If @sdevnew is not * NULL, store the address of the new Scsi_Device in *@sdevnew (needed * when scanning a particular LUN). * * 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, char *inq_result, int *bflags) { struct scsi_device *sdev_sibling; struct scsi_target *starget; unsigned long flags; /* * 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. */ sdev->inquiry = kmalloc(sdev->inquiry_len, GFP_ATOMIC); if (sdev->inquiry == NULL) { return SCSI_SCAN_NO_RESPONSE; } memcpy(sdev->inquiry, inq_result, sdev->inquiry_len); sdev->vendor = (char *) (sdev->inquiry + 8); sdev->model = (char *) (sdev->inquiry + 16); sdev->rev = (char *) (sdev->inquiry + 32); if (*bflags & BLIST_ISROM) { /* * It would be better to modify sdev->type, and set * sdev->removable, but then the print_inquiry() output * would not show TYPE_ROM; if print_inquiry() is removed * the issue goes away. */ inq_result[0] = TYPE_ROM; inq_result[1] |= 0x80; /* removable */ } switch (sdev->type = (inq_result[0] & 0x1f)) { case TYPE_TAPE: case TYPE_DISK: case TYPE_PRINTER: case TYPE_MOD: case TYPE_PROCESSOR: case TYPE_SCANNER: case TYPE_MEDIUM_CHANGER: case TYPE_ENCLOSURE: case TYPE_COMM: sdev->writeable = 1; break; case TYPE_WORM: case TYPE_ROM: sdev->writeable = 0; break; default: printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type); } print_inquiry(inq_result); /* * 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 * * XXX Save the PQ field let the upper layers figure out if they * want to attach or not to this device, do not set online FALSE; * otherwise, offline devices still get an sd allocated, and they * use up an sd slot. */ if (((inq_result[0] >> 5) & 7) == 1) { SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: peripheral" " qualifier of 1, device offlined\n")); scsi_device_set_state(sdev, SDEV_OFFLINE); } sdev->removable = (0x80 & inq_result[1]) >> 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; sprintf(sdev->devfs_name, "scsi/host%d/bus%d/target%d/lun%d", sdev->host->host_no, sdev->channel, sdev->id, sdev->lun); /* * End driverfs/devfs code. */ if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) && !(*bflags & BLIST_NOTQ)) sdev->tagged_supported = 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; /* * 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 we need to allow I/O to only one of the luns attached to * this target id at a time set single_lun, and allocate or modify * sdev_target. */ if (*bflags & BLIST_SINGLELUN) { sdev->single_lun = 1; spin_lock_irqsave(sdev->host->host_lock, flags); starget = NULL; /* * Search for an existing target for this sdev. */ list_for_each_entry(sdev_sibling, &sdev->same_target_siblings, same_target_siblings) { if (sdev_sibling->sdev_target != NULL) { starget = sdev_sibling->sdev_target; break; } } if (!starget) { starget = kmalloc(sizeof(*starget), GFP_ATOMIC); if (!starget) { printk(ALLOC_FAILURE_MSG, __FUNCTION__); spin_unlock_irqrestore(sdev->host->host_lock, flags); return SCSI_SCAN_NO_RESPONSE; } starget->starget_refcnt = 0; starget->starget_sdev_user = NULL; } starget->starget_refcnt++; sdev->sdev_target = starget; spin_unlock_irqrestore(sdev->host->host_lock, flags); } /* if the device needs this changing, it may do so in the detect * function */ sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED; sdev->use_10_for_rw = 1; if (*bflags & BLIST_MS_SKIP_PAGE_08) sdev->skip_ms_page_8 = 1; if (*bflags & BLIST_MS_SKIP_PAGE_3F) sdev->skip_ms_page_3f = 1; if (*bflags & BLIST_USE_10_BYTE_MS) sdev->use_10_for_ms = 1; /* set the device running here so that slave configure * may do I/O */ scsi_device_set_state(sdev, SDEV_RUNNING); if (*bflags & BLIST_MS_192_BYTES_FOR_3F) sdev->use_192_bytes_for_3f = 1; if(sdev->host->hostt->slave_configure) sdev->host->hostt->slave_configure(sdev); /* * Ok, the device is now all set up, we can * register it and tell the rest of the kernel * about it. */ scsi_sysfs_add_sdev(sdev); return SCSI_SCAN_LUN_PRESENT; } /** * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it * @sdevscan: probe the LUN corresponding to this Scsi_Device * @sdevnew: store the value of any new Scsi_Device allocated * @bflagsp: store bflags here if not NULL * * 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_Host *host, uint channel, uint id, uint lun, int *bflagsp, struct scsi_device **sdevp, int rescan) { struct scsi_device *sdev; struct scsi_request *sreq; unsigned char *result; int bflags, res = SCSI_SCAN_NO_RESPONSE; /* * The rescan flag is used as an optimization, the first scan of a * host adapter calls into here with rescan == 0. */ if (rescan) { sdev = scsi_device_lookup(host, channel, id, lun); if (sdev) { SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: device exists on <%d:%d:%d:%d>\n", host->host_no, channel, id, lun)); if (sdevp) *sdevp = sdev; if (bflagsp) *bflagsp = scsi_get_device_flags(sdev, sdev->vendor, sdev->model); /* XXX: bandaid until callers do refcounting */ scsi_device_put(sdev); return SCSI_SCAN_LUN_PRESENT; } } sdev = scsi_alloc_sdev(host, channel, id, lun); if (!sdev) goto out; sreq = scsi_allocate_request(sdev, GFP_ATOMIC); if (!sreq) goto out_free_sdev; result = kmalloc(256, GFP_ATOMIC | (host->unchecked_isa_dma) ? __GFP_DMA : 0); if (!result) goto out_free_sreq; scsi_probe_lun(sreq, result, &bflags); if (sreq->sr_result) goto out_free_result; /* * 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(3, printk(KERN_INFO "scsi scan: peripheral qualifier of 3," " no device added\n")); res = SCSI_SCAN_TARGET_PRESENT; goto out_free_result; } res = scsi_add_lun(sdev, result, &bflags); if (res == SCSI_SCAN_LUN_PRESENT) { if (bflags & BLIST_KEY) { sdev->lockable = 0; scsi_unlock_floptical(sreq, result); } if (bflagsp) *bflagsp = bflags; } out_free_result: kfree(result); out_free_sreq: scsi_release_request(sreq); out_free_sdev: if (res == SCSI_SCAN_LUN_PRESENT) { if (sdevp) *sdevp = sdev; } else { if (sdev->host->hostt->slave_destroy) sdev->host->hostt->slave_destroy(sdev); if (sdev->host->transportt->cleanup) sdev->host->transportt->cleanup(sdev); put_device(&sdev->sdev_gendev); } out: return res; } /** * scsi_sequential_lun_scan - sequentially scan a SCSI target * @sdevscan: scan the host, channel, and id of this Scsi_Device * @bflags: black/white list flag for LUN 0 * @lun0_res: result of scanning LUN 0 * * 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_Host *shost, uint channel, uint id, int bflags, int lun0_res, int scsi_level, int rescan) { unsigned int sparse_lun, lun, max_dev_lun; SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of" " host %d channel %d id %d\n", shost->host_no, channel, id)); 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 not sparse lun and no device attached at LUN 0 do not scan * any further. */ if (!sparse_lun && (lun0_res != SCSI_SCAN_LUN_PRESENT)) return; /* * If less than SCSI_1_CSS, and no special lun scaning, stop * scanning; this matches 2.4 behaviour, but could just be a bug * (to continue scanning a SCSI_1_CSS 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); /* * 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(shost, channel, id, lun, NULL, NULL, rescan) != SCSI_SCAN_LUN_PRESENT) && !sparse_lun) return; } #ifdef CONFIG_SCSI_REPORT_LUNS /** * scsilun_to_int: convert a scsi_lun to an int * @scsilun: struct scsi_lun to be converted. * * Description: * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered * integer, and return the result. The caller must check for * truncation before using this function. * * Notes: * The struct scsi_lun is assumed to be four levels, with each level * effectively containing a SCSI byte-ordered (big endian) short; the * addressing bits of each level are ignored (the highest two bits). * For a description of the LUN format, post SCSI-3 see the SCSI * Architecture Model, for SCSI-3 see the SCSI Controller Commands. * * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns * the integer: 0x0b030a04 **/ static int scsilun_to_int(struct scsi_lun *scsilun) { int i; unsigned int lun; lun = 0; for (i = 0; i < sizeof(lun); i += 2) lun = lun | (((scsilun->scsi_lun[i] << 8) | scsilun->scsi_lun[i + 1]) << (i * 8)); return lun; } /** * scsi_report_lun_scan - Scan using SCSI REPORT LUN results * @sdevscan: scan the host, channel, and id of this Scsi_Device * * Description: * If @sdevscan is for a SCSI-3 or up device, send a REPORT LUN * command, and scan the resulting list of LUNs by calling * scsi_probe_and_add_lun. * * Modifies sdevscan->lun. * * Return: * 0: scan completed (or no memory, so further scanning is futile) * 1: no report lun scan, or not configured **/ static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags, int rescan) { char devname[64]; unsigned char scsi_cmd[MAX_COMMAND_SIZE]; unsigned int length; unsigned int lun; unsigned int num_luns; unsigned int retries; struct scsi_lun *lunp, *lun_data; struct scsi_request *sreq; u8 *data; /* * Only support SCSI-3 and up devices. */ if (sdev->scsi_level < SCSI_3) return 1; if (bflags & BLIST_NOLUN) return 0; sreq = scsi_allocate_request(sdev, GFP_ATOMIC); if (!sreq) goto out; sprintf(devname, "host %d channel %d id %d", sdev->host->host_no, sdev->channel, sdev->id); /* * Allocate enough to hold the header (the same size as one scsi_lun) * plus the max number of luns we are requesting. * * Reallocating and trying again (with the exact amount we need) * would be nice, but then we need to somehow limit the size * allocated based on the available memory and the limits of * kmalloc - we don't want a kmalloc() failure of a huge value to * prevent us from finding any LUNs on this target. */ length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun); lun_data = kmalloc(length, GFP_ATOMIC | (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0)); if (!lun_data) goto out_release_request; 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. */ scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff; scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff; scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff; scsi_cmd[9] = (unsigned char) length & 0xff; scsi_cmd[10] = 0; /* reserved */ scsi_cmd[11] = 0; /* control */ sreq->sr_cmd_len = 0; sreq->sr_data_direction = DMA_FROM_DEVICE; /* * 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, printk (KERN_INFO "scsi scan: Sending" " REPORT LUNS to %s (try %d)\n", devname, retries)); scsi_wait_req(sreq, scsi_cmd, lun_data, length, SCSI_TIMEOUT + 4*HZ, 3); SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS" " %s (try %d) result 0x%x\n", sreq->sr_result ? "failed" : "successful", retries, sreq->sr_result)); if (sreq->sr_result == 0 || sreq->sr_sense_buffer[2] != UNIT_ATTENTION) break; } if (sreq->sr_result) { /* * The device probably does not support a REPORT LUN command */ kfree(lun_data); scsi_release_request(sreq); return 1; } scsi_release_request(sreq); /* * Get the length from the first four bytes of lun_data. */ data = (u8 *) lun_data->scsi_lun; length = ((data[0] << 24) | (data[1] << 16) | (data[2] << 8) | (data[3] << 0)); num_luns = (length / sizeof(struct scsi_lun)); if (num_luns > max_scsi_report_luns) { printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)" " of %d luns reported, try increasing" " max_scsi_report_luns.\n", devname, max_scsi_report_luns, num_luns); num_luns = max_scsi_report_luns; } SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUN scan of" " host %d channel %d id %d\n", sdev->host->host_no, sdev->channel, sdev->id)); /* * 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); /* * Check if the unused part of lunp is non-zero, and so * does not fit in lun. */ if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) { int i; /* * Output an error displaying the LUN in byte order, * this differs from what linux would print for the * integer LUN value. */ printk(KERN_WARNING "scsi: %s lun 0x", devname); data = (char *)lunp->scsi_lun; for (i = 0; i < sizeof(struct scsi_lun); i++) printk("%02x", data[i]); printk(" has a LUN larger than currently supported.\n"); } else if (lun == 0) { /* * LUN 0 has already been scanned. */ } else if (lun > sdev->host->max_lun) { printk(KERN_WARNING "scsi: %s lun%d has a LUN larger" " than allowed by the host adapter\n", devname, lun); } else { int res; res = scsi_probe_and_add_lun(sdev->host, sdev->channel, sdev->id, lun, NULL, NULL, rescan); if (res == SCSI_SCAN_NO_RESPONSE) { /* * Got some results, but now none, abort. */ printk(KERN_ERR "scsi: Unexpected response" " from %s lun %d while scanning, scan" " aborted\n", devname, lun); break; } } } kfree(lun_data); return 0; out_release_request: scsi_release_request(sreq); out: /* * We are out of memory, don't try scanning any further. */ printk(ALLOC_FAILURE_MSG, __FUNCTION__); return 0; } #else # define scsi_report_lun_scan(sdev, blags, rescan) (1) #endif /* CONFIG_SCSI_REPORT_LUNS */ struct scsi_device *scsi_add_device(struct Scsi_Host *shost, uint channel, uint id, uint lun) { struct scsi_device *sdev; int res; down(&shost->scan_mutex); res = scsi_probe_and_add_lun(shost, channel, id, lun, NULL, &sdev, 1); if (res != SCSI_SCAN_LUN_PRESENT) sdev = ERR_PTR(-ENODEV); up(&shost->scan_mutex); return sdev; } void scsi_rescan_device(struct device *dev) { struct scsi_driver *drv; if (!dev->driver) return; drv = to_scsi_driver(dev->driver); if (try_module_get(drv->owner)) { if (drv->rescan) drv->rescan(dev); module_put(drv->owner); } } /** * scsi_scan_target - scan a target id, possibly including all LUNs on the * target. * @sdevsca: Scsi_Device handle for scanning * @shost: host to scan * @channel: channel to scan * @id: target id to scan * * Description: * Scan the target id on @shost, @channel, and @id. Scan at least LUN * 0, and possibly all LUNs on the target id. * * Use the pre-allocated @sdevscan as a handle for the scanning. This * function sets sdevscan->host, sdevscan->id and sdevscan->lun; the * scanning functions modify sdevscan->lun. * * First try a REPORT LUN scan, if that does not scan the target, do a * sequential scan of LUNs on the target id. **/ static void scsi_scan_target(struct Scsi_Host *shost, unsigned int channel, unsigned int id, unsigned int lun, int rescan) { int bflags = 0; int res; struct scsi_device *sdev; if (shost->this_id == id) /* * Don't scan the host adapter */ return; if (lun != SCAN_WILD_CARD) { /* * Scan for a specific host/chan/id/lun. */ scsi_probe_and_add_lun(shost, channel, id, lun, NULL, NULL, rescan); return; } /* * 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(shost, channel, id, 0, &bflags, &sdev, rescan); if (res == SCSI_SCAN_LUN_PRESENT) { if (scsi_report_lun_scan(sdev, bflags, rescan) != 0) /* * The REPORT LUN did not scan the target, * do a sequential scan. */ scsi_sequential_lun_scan(shost, channel, id, bflags, res, sdev->scsi_level, rescan); } else if (res == SCSI_SCAN_TARGET_PRESENT) { /* * There's a target here, but lun 0 is offline so we * can't use the report_lun scan. Fall back to a * sequential lun scan with a bflags of SPARSELUN and * a default scsi level of SCSI_2 */ scsi_sequential_lun_scan(shost, channel, id, BLIST_SPARSELUN, SCSI_SCAN_TARGET_PRESENT, SCSI_2, rescan); } } static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel, unsigned int id, unsigned int lun, int 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, channel, order_id, lun, rescan); } else scsi_scan_target(shost, channel, id, lun, rescan); } int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, unsigned int id, unsigned int lun, int rescan) { SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "%s: <%u:%u:%u:%u>\n", __FUNCTION__, shost->host_no, 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; down(&shost->scan_mutex); 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); up(&shost->scan_mutex); return 0; } /** * scsi_scan_host - scan the given adapter * @shost: adapter to scan **/ void scsi_scan_host(struct Scsi_Host *shost) { scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, SCAN_WILD_CARD, 0); } void scsi_forget_host(struct Scsi_Host *shost) { struct scsi_device *sdev, *tmp; unsigned long flags; /* * Ok, this look a bit strange. We always look for the first device * on the list as scsi_remove_device removes them from it - thus we * also have to release the lock. * We don't need to get another reference to the device before * releasing the lock as we already own the reference from * scsi_register_device that's release in scsi_remove_device. And * after that we don't look at sdev anymore. */ spin_lock_irqsave(shost->host_lock, flags); list_for_each_entry_safe(sdev, tmp, &shost->__devices, siblings) { spin_unlock_irqrestore(shost->host_lock, flags); scsi_remove_device(sdev); spin_lock_irqsave(shost->host_lock, flags); } spin_unlock_irqrestore(shost->host_lock, flags); } /* * Function: scsi_get_host_dev() * * Purpose: Create a Scsi_Device that points to the host adapter itself. * * Arguments: SHpnt - 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; sdev = scsi_alloc_sdev(shost, 0, shost->this_id, 0); if (sdev) { sdev->borken = 0; } return sdev; } /* * Function: scsi_free_host_dev() * * Purpose: Free a scsi_device that points to the host adapter itself. * * Arguments: SHpnt - Host that needs a Scsi_Device * * Lock status: None assumed. * * Returns: Nothing * * Notes: */ void scsi_free_host_dev(struct scsi_device *sdev) { BUG_ON(sdev->id != sdev->host->this_id); if (sdev->host->hostt->slave_destroy) sdev->host->hostt->slave_destroy(sdev); if (sdev->host->transportt->cleanup) sdev->host->transportt->cleanup(sdev); put_device(&sdev->sdev_gendev); }