/* * 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 <linux/config.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/init.h> #include <linux/blkdev.h> #include <asm/semaphore.h> #include <scsi/scsi.h> #include <scsi/scsi_device.h> #include <scsi/scsi_driver.h> #include <scsi/scsi_devinfo.h> #include <scsi/scsi_host.h> #include <scsi/scsi_request.h> #include <scsi/scsi_transport.h> #include <scsi/scsi_eh.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" /* * Default timeout */ #define SCSI_TIMEOUT (2*HZ) /* * 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)"); /* * 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 = 511; 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)"); static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ+3; module_param_named(inq_timeout, scsi_inq_timeout, int, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(inq_timeout, "Timeout (in seconds) waiting for devices to answer INQUIRY." " Default is 5. Some non-compliant devices need more."); /** * 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]; 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; scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL, 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_target *starget, unsigned int lun, void *hostdata) { struct scsi_device *sdev; int display_failure_msg = 1, ret; struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); sdev = kmalloc(sizeof(*sdev) + shost->transportt->device_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 = starget->id; sdev->lun = lun; sdev->channel = starget->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); 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->request_queue = scsi_alloc_queue(sdev); if (!sdev->request_queue) { /* release fn is set up in scsi_sysfs_device_initialise, so * have to free and put manually here */ put_device(&starget->dev); goto out; } sdev->request_queue->queuedata = sdev; scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); 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: transport_destroy_device(&sdev->sdev_gendev); scsi_free_queue(sdev->request_queue); put_device(&sdev->sdev_gendev); out: if (display_failure_msg) printk(ALLOC_FAILURE_MSG, __FUNCTION__); return NULL; } static void scsi_target_dev_release(struct device *dev) { struct device *parent = dev->parent; struct scsi_target *starget = to_scsi_target(dev); struct Scsi_Host *shost = dev_to_shost(parent); if (shost->hostt->target_destroy) shost->hostt->target_destroy(starget); kfree(starget); put_device(parent); } int scsi_is_target_device(const struct device *dev) { return dev->release == scsi_target_dev_release; } 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; } 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; /* * Obtain the real parent from the transport. The transport * is allowed to fail (no error) if there is nothing at that * target id. */ if (shost->transportt->target_parent) { spin_lock_irqsave(shost->host_lock, flags); parent = shost->transportt->target_parent(shost, channel, id); spin_unlock_irqrestore(shost->host_lock, flags); if (!parent) return NULL; } starget = kmalloc(size, GFP_KERNEL); if (!starget) { printk(KERN_ERR "%s: allocation failure\n", __FUNCTION__); return NULL; } memset(starget, 0, size); dev = &starget->dev; device_initialize(dev); starget->reap_ref = 1; dev->parent = get_device(parent); dev->release = scsi_target_dev_release; sprintf(dev->bus_id, "target%d:%d:%d", shost->host_no, channel, id); starget->id = id; starget->channel = channel; INIT_LIST_HEAD(&starget->siblings); INIT_LIST_HEAD(&starget->devices); 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); device_add(dev); transport_add_device(dev); if (shost->hostt->target_alloc) { int error = shost->hostt->target_alloc(starget); if(error) { dev_printk(KERN_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 */ get_device(dev); scsi_target_reap(starget); put_device(dev); return NULL; } } return starget; found: found_target->reap_ref++; spin_unlock_irqrestore(shost->host_lock, flags); put_device(parent); kfree(starget); return found_target; } /** * 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) { struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); unsigned long flags; spin_lock_irqsave(shost->host_lock, flags); if (--starget->reap_ref == 0 && list_empty(&starget->devices)) { list_del_init(&starget->siblings); spin_unlock_irqrestore(shost->host_lock, flags); device_del(&starget->dev); transport_unregister_device(&starget->dev); put_device(&starget->dev); return; } spin_unlock_irqrestore(shost->host_lock, flags); } /** * 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, char *inq_result, int result_len, int *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, printk(KERN_INFO "scsi scan: INQUIRY pass %d " "to host %d channel %d id %d lun %d, length %d\n", pass, sdev->host->host_no, sdev->channel, sdev->id, sdev->lun, try_inquiry_len)); /* Each pass gets up to three chances to ignore Unit Attention */ for (count = 0; count < 3; ++count) { 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); SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s " "with code 0x%x\n", result ? "failed" : "successful", result)); if (result) { /* * 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 ((driver_byte(result) & DRIVER_SENSE) && scsi_sense_valid(&sshdr)) { if ((sshdr.sense_key == UNIT_ATTENTION) && ((sshdr.asc == 0x28) || (sshdr.asc == 0x29)) && (sshdr.ascq == 0)) continue; } } break; } if (result == 0) { response_len = (unsigned char) 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 (BLIST_INQUIRY_58 & *bflags) next_inquiry_len = 58; 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) { printk(KERN_INFO "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. * * 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; return 0; } /** * 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) { /* * 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 */ } else if (*bflags & BLIST_NO_ULD_ATTACH) sdev->no_uld_attach = 1; 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: case TYPE_RBC: 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 * * 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->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; /* * 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; /* * 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) sdev->single_lun = 1; 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 (*bflags & BLIST_NOT_LOCKABLE) sdev->lockable = 0; if (*bflags & BLIST_RETRY_HWERROR) sdev->retry_hwerror = 1; transport_configure_device(&sdev->sdev_gendev); 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. */ if (scsi_sysfs_add_sdev(sdev) != 0) return SCSI_SCAN_NO_RESPONSE; return SCSI_SCAN_LUN_PRESENT; } static inline void scsi_destroy_sdev(struct scsi_device *sdev) { if (sdev->host->hostt->slave_destroy) sdev->host->hostt->slave_destroy(sdev); transport_destroy_device(&sdev->sdev_gendev); put_device(&sdev->sdev_gendev); } /** * 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 * @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_target *starget, uint lun, int *bflagsp, struct scsi_device **sdevp, int rescan, void *hostdata) { struct scsi_device *sdev; unsigned char *result; int bflags, 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 || sdev->sdev_state != SDEV_CREATED) { SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: device exists on %s\n", sdev->sdev_gendev.bus_id)); 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_ATOMIC | ((shost->unchecked_isa_dma) ? __GFP_DMA : 0)); if (!result) goto out_free_sdev; if (scsi_probe_lun(sdev, result, result_len, &bflags)) 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(sdev, result); } if (bflagsp) *bflagsp = bflags; } 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_destroy_sdev(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 * @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_target *starget, int bflags, int lun0_res, int scsi_level, int rescan) { unsigned int sparse_lun, lun, max_dev_lun; struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of" "%s\n", starget->dev.bus_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(starget, lun, NULL, NULL, rescan, NULL) != SCSI_SCAN_LUN_PRESENT) && !sparse_lun) return; } /** * 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; } /** * int_to_scsilun: reverts an int into a scsi_lun * @int: integer to be reverted * @scsilun: struct scsi_lun to be set. * * Description: * Reverts the functionality of the scsilun_to_int, which packed * an 8-byte lun value into an int. This routine unpacks the int * back into the lun value. * Note: the scsilun_to_int() routine does not truly handle all * 8bytes of the lun value. This functions restores only as much * as was set by the routine. * * Notes: * Given an integer : 0x0b030a04, this function returns a * scsi_lun of : struct scsi_lun of: 0a 04 0b 03 00 00 00 00 * **/ void int_to_scsilun(unsigned int lun, struct scsi_lun *scsilun) { int i; memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun)); for (i = 0; i < sizeof(lun); i += 2) { scsilun->scsi_lun[i] = (lun >> 8) & 0xFF; scsilun->scsi_lun[i+1] = lun & 0xFF; lun = lun >> 16; } } EXPORT_SYMBOL(int_to_scsilun); /** * 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_target *starget, 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; int result; struct scsi_lun *lunp, *lun_data; u8 *data; struct scsi_sense_hdr sshdr; struct scsi_device *sdev; struct Scsi_Host *shost = dev_to_shost(&starget->dev); /* * 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. */ if ((bflags & BLIST_NOREPORTLUN) || starget->scsi_level < SCSI_2 || (starget->scsi_level < SCSI_3 && (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) ) return 1; if (bflags & BLIST_NOLUN) return 0; 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)) return 0; } sprintf(devname, "host %d channel %d id %d", shost->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) { printk(ALLOC_FAILURE_MSG, __FUNCTION__); 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. */ 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 */ /* * 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)); result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, lun_data, length, &sshdr, SCSI_TIMEOUT + 4 * HZ, 3); SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "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 */ kfree(lun_data); return 1; } /* * 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 > 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(starget, lun, NULL, NULL, rescan, NULL); 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); out: scsi_device_put(sdev); if (sdev->sdev_state == SDEV_CREATED) /* * the sdev we used didn't appear in the report luns scan */ scsi_destroy_sdev(sdev); return 0; } struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, uint id, uint lun, void *hostdata) { struct scsi_device *sdev; struct device *parent = &shost->shost_gendev; int res; struct scsi_target *starget = scsi_alloc_target(parent, channel, id); if (!starget) return ERR_PTR(-ENOMEM); get_device(&starget->dev); down(&shost->scan_mutex); if (scsi_host_scan_allowed(shost)) { res = scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); if (res != SCSI_SCAN_LUN_PRESENT) sdev = ERR_PTR(-ENODEV); } up(&shost->scan_mutex); 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, uint 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_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); } } EXPORT_SYMBOL(scsi_rescan_device); static void __scsi_scan_target(struct device *parent, unsigned int channel, unsigned int id, unsigned int lun, int rescan) { struct Scsi_Host *shost = dev_to_shost(parent); int 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; get_device(&starget->dev); 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, res, starget->scsi_level, rescan); } out_reap: /* now 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 * * 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, unsigned int lun, int rescan) { struct Scsi_Host *shost = dev_to_shost(parent); down(&shost->scan_mutex); if (scsi_host_scan_allowed(shost)) __scsi_scan_target(parent, channel, id, lun, rescan); up(&shost->scan_mutex); } EXPORT_SYMBOL(scsi_scan_target); 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->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, 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 (scsi_host_scan_allowed(shost)) { 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); } EXPORT_SYMBOL(scsi_scan_host); /** * scsi_scan_single_target - scan the given SCSI target * @shost: adapter to scan * @chan: channel to scan * @id: target id to scan **/ void scsi_scan_single_target(struct Scsi_Host *shost, unsigned int chan, unsigned int id) { scsi_scan_host_selected(shost, chan, id, SCAN_WILD_CARD, 1); } EXPORT_SYMBOL(scsi_scan_single_target); 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); } /* * 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 = NULL; struct scsi_target *starget; down(&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->sdev_gendev.parent = get_device(&starget->dev); sdev->borken = 0; } put_device(&starget->dev); out: up(&shost->scan_mutex); return sdev; } EXPORT_SYMBOL(scsi_get_host_dev); /* * 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); scsi_destroy_sdev(sdev); } EXPORT_SYMBOL(scsi_free_host_dev);