diff options
Diffstat (limited to 'drivers/scsi/scsi_scan.c')
-rw-r--r-- | drivers/scsi/scsi_scan.c | 1473 |
1 files changed, 1473 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c new file mode 100644 index 000000000000..a8a37a338c02 --- /dev/null +++ b/drivers/scsi/scsi_scan.c @@ -0,0 +1,1473 @@ +/* + * 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 + * @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_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; + + spin_lock_init(&sdev->sdev_lock); + 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); + 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 = kmalloc(size, GFP_ATOMIC); + struct scsi_target *found_target; + + 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(&starget->dev); + device_add(&starget->dev); + transport_add_device(&starget->dev); + 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 + * @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 first_inquiry_len, try_inquiry_len, next_inquiry_len; + int response_len = 0; + int pass, count; + 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; + sreq->sr_cmd_len = 0; + sreq->sr_data_direction = DMA_FROM_DEVICE; + + memset(inq_result, 0, try_inquiry_len); + scsi_wait_req(sreq, (void *) scsi_cmd, (void *) inq_result, + try_inquiry_len, + HZ/2 + HZ*scsi_inq_timeout, 3); + + SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s " + "with code 0x%x\n", + sreq->sr_result ? "failed" : "successful", + sreq->sr_result)); + + if (sreq->sr_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(sreq->sr_result) & DRIVER_SENSE) && + scsi_request_normalize_sense(sreq, &sshdr)) { + if ((sshdr.sense_key == UNIT_ATTENTION) && + ((sshdr.asc == 0x28) || + (sshdr.asc == 0x29)) && + (sshdr.ascq == 0)) + continue; + } + } + break; + } + + if (sreq->sr_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 (sreq->sr_result) + return; + + /* 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++; + + 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) +{ + /* + * 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: + 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. + */ + 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 + * @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; + struct scsi_request *sreq; + unsigned char *result; + int bflags, res = SCSI_SCAN_NO_RESPONSE; + 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. + */ + if (rescan) { + sdev = scsi_device_lookup_by_target(starget, lun); + if (sdev) { + 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; + } + } + + sdev = scsi_alloc_sdev(starget, lun, hostdata); + if (!sdev) + goto out; + sreq = scsi_allocate_request(sdev, GFP_ATOMIC); + if (!sreq) + goto out_free_sdev; + result = kmalloc(256, GFP_ATOMIC | + (shost->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) { + scsi_device_get(sdev); + *sdevp = sdev; + } + } else { + if (sdev->host->hostt->slave_destroy) + sdev->host->hostt->slave_destroy(sdev); + transport_destroy_device(&sdev->sdev_gendev); + put_device(&sdev->sdev_gendev); + } + 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; +} + +/** + * 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; + struct scsi_sense_hdr sshdr; + struct scsi_target *starget = scsi_target(sdev); + + /* + * 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) || + sdev->scsi_level < SCSI_2 || + (sdev->scsi_level < SCSI_3 && + (!(bflags & BLIST_REPORTLUN2) || sdev->host->max_lun <= 8)) ) + 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) + break; + else if (scsi_request_normalize_sense(sreq, &sshdr)) { + if (sshdr.sense_key != 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(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); + 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; +} + +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); + + down(&shost->scan_mutex); + 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); + +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); + +/** + * 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. + **/ +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_device *sdev = NULL; + 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, &sdev, rescan, NULL); + 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(starget, 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(starget, BLIST_SPARSELUN, + SCSI_SCAN_TARGET_PRESENT, SCSI_2, rescan); + } + if (sdev) + scsi_device_put(sdev); + + 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); +} +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 (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_target *starget, *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(starget, tmp, &shost->__targets, siblings) { + spin_unlock_irqrestore(shost->host_lock, flags); + scsi_remove_target(&starget->dev); + 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; + struct scsi_target *starget; + + starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id); + if (!starget) + return NULL; + + sdev = scsi_alloc_sdev(starget, 0, NULL); + if (sdev) { + sdev->sdev_gendev.parent = get_device(&starget->dev); + sdev->borken = 0; + } + put_device(&starget->dev); + 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); + + if (sdev->host->hostt->slave_destroy) + sdev->host->hostt->slave_destroy(sdev); + transport_destroy_device(&sdev->sdev_gendev); + put_device(&sdev->sdev_gendev); +} +EXPORT_SYMBOL(scsi_free_host_dev); + |