X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Fscsi%2Fscsi_scan.c;h=20df7fe4f48fe05a694a780a2e2b218235841da9;hb=14e660e677ddd3574247495aae4ef63eb8899072;hp=fd9e281c3bfeed4fef893cb705e7c8331011c7bd;hpb=884d25cc4fda20908fd4ef93dbb41d817984b68b;p=safe%2Fjmp%2Flinux-2.6 diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index fd9e281..20df7fe 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -29,7 +29,9 @@ #include #include #include -#include +#include +#include +#include #include #include @@ -52,7 +54,7 @@ #define SCSI_TIMEOUT (2*HZ) /* - * Prefix values for the SCSI id's (stored in driverfs name field) + * Prefix values for the SCSI id's (stored in sysfs name field) */ #define SCSI_UID_SER_NUM 'S' #define SCSI_UID_UNKNOWN 'Z' @@ -83,10 +85,21 @@ static unsigned int max_scsi_luns = MAX_SCSI_LUNS; static unsigned int max_scsi_luns = 1; #endif -module_param_named(max_luns, max_scsi_luns, int, S_IRUGO|S_IWUSR); +module_param_named(max_luns, max_scsi_luns, uint, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(max_luns, "last scsi LUN (should be between 1 and 2^32-1)"); +#ifdef CONFIG_SCSI_SCAN_ASYNC +#define SCSI_SCAN_TYPE_DEFAULT "async" +#else +#define SCSI_SCAN_TYPE_DEFAULT "sync" +#endif + +static char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT; + +module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO); +MODULE_PARM_DESC(scan, "sync, async or none"); + /* * max_scsi_report_luns: the maximum number of LUNS that will be * returned from the REPORT LUNS command. 8 times this value must @@ -96,18 +109,91 @@ MODULE_PARM_DESC(max_luns, */ static unsigned int max_scsi_report_luns = 511; -module_param_named(max_report_luns, max_scsi_report_luns, int, S_IRUGO|S_IWUSR); +module_param_named(max_report_luns, max_scsi_report_luns, uint, 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_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(inq_timeout, "Timeout (in seconds) waiting for devices to answer INQUIRY." " Default is 5. Some non-compliant devices need more."); +/* This lock protects only this list */ +static DEFINE_SPINLOCK(async_scan_lock); +static LIST_HEAD(scanning_hosts); + +struct async_scan_data { + struct list_head list; + struct Scsi_Host *shost; + struct completion prev_finished; +}; + +/** + * scsi_complete_async_scans - Wait for asynchronous scans to complete + * + * When this function returns, any host which started scanning before + * this function was called will have finished its scan. Hosts which + * started scanning after this function was called may or may not have + * finished. + */ +int scsi_complete_async_scans(void) +{ + struct async_scan_data *data; + + do { + if (list_empty(&scanning_hosts)) + return 0; + /* If we can't get memory immediately, that's OK. Just + * sleep a little. Even if we never get memory, the async + * scans will finish eventually. + */ + data = kmalloc(sizeof(*data), GFP_KERNEL); + if (!data) + msleep(1); + } while (!data); + + data->shost = NULL; + init_completion(&data->prev_finished); + + spin_lock(&async_scan_lock); + /* Check that there's still somebody else on the list */ + if (list_empty(&scanning_hosts)) + goto done; + list_add_tail(&data->list, &scanning_hosts); + spin_unlock(&async_scan_lock); + + printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n"); + wait_for_completion(&data->prev_finished); + + spin_lock(&async_scan_lock); + list_del(&data->list); + if (!list_empty(&scanning_hosts)) { + struct async_scan_data *next = list_entry(scanning_hosts.next, + struct async_scan_data, list); + complete(&next->prev_finished); + } + done: + spin_unlock(&async_scan_lock); + + kfree(data); + return 0; +} + +/* Only exported for the benefit of scsi_wait_scan */ +EXPORT_SYMBOL_GPL(scsi_complete_async_scans); + +#ifndef MODULE +/* + * For async scanning we need to wait for all the scans to complete before + * trying to mount the root fs. Otherwise non-modular drivers may not be ready + * yet. + */ +late_initcall(scsi_complete_async_scans); +#endif + /** * scsi_unlock_floptical - unlock device via a special MODE SENSE command * @sdev: scsi device to send command to @@ -307,6 +393,7 @@ static struct scsi_target *scsi_alloc_target(struct device *parent, INIT_LIST_HEAD(&starget->siblings); INIT_LIST_HEAD(&starget->devices); starget->state = STARGET_RUNNING; + starget->scsi_level = SCSI_2; retry: spin_lock_irqsave(shost->host_lock, flags); @@ -362,9 +449,10 @@ static struct scsi_target *scsi_alloc_target(struct device *parent, goto retry; } -static void scsi_target_reap_usercontext(void *data) +static void scsi_target_reap_usercontext(struct work_struct *work) { - struct scsi_target *starget = data; + struct scsi_target *starget = + container_of(work, struct scsi_target, ew.work); struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); unsigned long flags; @@ -400,7 +488,7 @@ void scsi_target_reap(struct scsi_target *starget) starget->state = STARGET_DEL; spin_unlock_irqrestore(shost->host_lock, flags); execute_in_process_context(scsi_target_reap_usercontext, - starget, &starget->ew); + &starget->ew); return; } @@ -575,6 +663,19 @@ static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, * short INQUIRY), an abort here prevents any further use of the * device, including spin up. * + * On the whole, the best approach seems to be to assume the first + * 36 bytes are valid no matter what the device says. That's + * better than copying < 36 bytes to the inquiry-result buffer + * and displaying garbage for the Vendor, Product, or Revision + * strings. + */ + if (sdev->inquiry_len < 36) { + printk(KERN_INFO "scsi scan: INQUIRY result too short (%d)," + " using 36\n", sdev->inquiry_len); + sdev->inquiry_len = 36; + } + + /* * Related to the above issue: * * XXX Devices (disk or all?) should be sent a TEST UNIT READY, @@ -603,23 +704,21 @@ static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result, /** * 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 + * @sdev: holds information to be stored in the new scsi_device * @inq_result: holds the result of a previous INQUIRY to the LUN * @bflags: black/white list flag + * @async: 1 if this device is being scanned asynchronously * * Description: - * 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). + * Initialize the scsi_device @sdev. Optionally set fields based + * on values in *@bflags. * * Return: * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized **/ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, - int *bflags) + int *bflags, int async) { /* * XXX do not save the inquiry, since it can change underneath us, @@ -631,28 +730,36 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, * 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) { + + /* + * Copy at least 36 bytes of INQUIRY data, so that we don't + * dereference unallocated memory when accessing the Vendor, + * Product, and Revision strings. Badly behaved devices may set + * the INQUIRY Additional Length byte to a small value, indicating + * these strings are invalid, but often they contain plausible data + * nonetheless. It doesn't matter if the device sent < 36 bytes + * total, since scsi_probe_lun() initializes inq_result with 0s. + */ + sdev->inquiry = kmemdup(inq_result, + max_t(size_t, sdev->inquiry_len, 36), + GFP_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; this can now be done since - * print_inquiry has gone away. - */ - inq_result[0] = TYPE_ROM; - inq_result[1] |= 0x80; /* removable */ - } else if (*bflags & BLIST_NO_ULD_ATTACH) - sdev->no_uld_attach = 1; + sdev->type = TYPE_ROM; + sdev->removable = 1; + } else { + sdev->type = (inq_result[0] & 0x1f); + sdev->removable = (inq_result[1] & 0x80) >> 7; + } - switch (sdev->type = (inq_result[0] & 0x1f)) { + switch (sdev->type) { + case TYPE_RBC: case TYPE_TAPE: case TYPE_DISK: case TYPE_PRINTER: @@ -663,17 +770,25 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, case TYPE_ENCLOSURE: case TYPE_COMM: case TYPE_RAID: - case TYPE_RBC: sdev->writeable = 1; break; - case TYPE_WORM: case TYPE_ROM: + case TYPE_WORM: sdev->writeable = 0; break; default: printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type); } + if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) { + /* RBC and MMC devices can return SCSI-3 compliance and yet + * still not support REPORT LUNS, so make them act as + * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is + * specifically set */ + if ((*bflags & BLIST_REPORTLUN2) == 0) + *bflags |= BLIST_NOREPORTLUN; + } + /* * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI * spec says: The device server is capable of supporting the @@ -691,12 +806,11 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, */ 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)) + 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; @@ -709,13 +823,10 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, sdev->inq_periph_qual, inq_result[2] & 0x07, (inq_result[3] & 0x0f) == 1 ? " CCS" : ""); - /* - * End sysfs 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 @@ -724,6 +835,9 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, if ((*bflags & BLIST_BORKEN) == 0) sdev->borken = 0; + if (*bflags & BLIST_NO_ULD_ATTACH) + sdev->no_uld_attach = 1; + /* * Apparently some really broken devices (contrary to the SCSI * standards) need to be selected without asserting ATN @@ -748,7 +862,6 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, if (*bflags & BLIST_SINGLELUN) sdev->single_lun = 1; - sdev->use_10_for_rw = 1; if (*bflags & BLIST_MS_SKIP_PAGE_08) @@ -795,7 +908,7 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, * register it and tell the rest of the kernel * about it. */ - if (scsi_sysfs_add_sdev(sdev) != 0) + if (!async && scsi_sysfs_add_sdev(sdev) != 0) return SCSI_SCAN_NO_RESPONSE; return SCSI_SCAN_LUN_PRESENT; @@ -926,7 +1039,7 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget, sdev_printk(KERN_INFO, sdev, "scsi scan: consider passing scsi_mod." - "dev_flags=%s:%s:0x240 or 0x800240\n", + "dev_flags=%s:%s:0x240 or 0x1000240\n", scsi_inq_str(vend, result, 8, 16), scsi_inq_str(mod, result, 16, 32)); }); @@ -964,7 +1077,7 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget, goto out_free_result; } - res = scsi_add_lun(sdev, result, &bflags); + res = scsi_add_lun(sdev, result, &bflags, shost->async_scan); if (res == SCSI_SCAN_LUN_PRESENT) { if (bflags & BLIST_KEY) { sdev->lockable = 0; @@ -1089,7 +1202,7 @@ static void scsi_sequential_lun_scan(struct scsi_target *starget, * 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 scsilun_to_int(struct scsi_lun *scsilun) { int i; unsigned int lun; @@ -1100,6 +1213,7 @@ static int scsilun_to_int(struct scsi_lun *scsilun) scsilun->scsi_lun[i + 1]) << (i * 8)); return lun; } +EXPORT_SYMBOL(scsilun_to_int); /** * int_to_scsilun: reverts an int into a scsi_lun @@ -1350,11 +1464,17 @@ struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel, struct device *parent = &shost->shost_gendev; struct scsi_target *starget; + if (strncmp(scsi_scan_type, "none", 4) == 0) + return ERR_PTR(-ENODEV); + starget = scsi_alloc_target(parent, channel, id); if (!starget) return ERR_PTR(-ENOMEM); mutex_lock(&shost->scan_mutex); + if (!shost->async_scan) + scsi_complete_async_scans(); + if (scsi_host_scan_allowed(shost)) scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata); mutex_unlock(&shost->scan_mutex); @@ -1464,7 +1584,13 @@ void scsi_scan_target(struct device *parent, unsigned int channel, { struct Scsi_Host *shost = dev_to_shost(parent); + if (strncmp(scsi_scan_type, "none", 4) == 0) + return; + mutex_lock(&shost->scan_mutex); + if (!shost->async_scan) + scsi_complete_async_scans(); + if (scsi_host_scan_allowed(shost)) __scsi_scan_target(parent, channel, id, lun, rescan); mutex_unlock(&shost->scan_mutex); @@ -1515,6 +1641,9 @@ int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, return -EINVAL; mutex_lock(&shost->scan_mutex); + if (!shost->async_scan) + scsi_complete_async_scans(); + if (scsi_host_scan_allowed(shost)) { if (channel == SCAN_WILD_CARD) for (channel = 0; channel <= shost->max_channel; @@ -1529,14 +1658,159 @@ int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel, return 0; } +static void scsi_sysfs_add_devices(struct Scsi_Host *shost) +{ + struct scsi_device *sdev; + shost_for_each_device(sdev, shost) { + if (!scsi_host_scan_allowed(shost) || + scsi_sysfs_add_sdev(sdev) != 0) + scsi_destroy_sdev(sdev); + } +} + +/** + * scsi_prep_async_scan - prepare for an async scan + * @shost: the host which will be scanned + * Returns: a cookie to be passed to scsi_finish_async_scan() + * + * Tells the midlayer this host is going to do an asynchronous scan. + * It reserves the host's position in the scanning list and ensures + * that other asynchronous scans started after this one won't affect the + * ordering of the discovered devices. + */ +static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost) +{ + struct async_scan_data *data; + unsigned long flags; + + if (strncmp(scsi_scan_type, "sync", 4) == 0) + return NULL; + + if (shost->async_scan) { + printk("%s called twice for host %d", __FUNCTION__, + shost->host_no); + dump_stack(); + return NULL; + } + + data = kmalloc(sizeof(*data), GFP_KERNEL); + if (!data) + goto err; + data->shost = scsi_host_get(shost); + if (!data->shost) + goto err; + init_completion(&data->prev_finished); + + mutex_lock(&shost->scan_mutex); + spin_lock_irqsave(shost->host_lock, flags); + shost->async_scan = 1; + spin_unlock_irqrestore(shost->host_lock, flags); + mutex_unlock(&shost->scan_mutex); + + spin_lock(&async_scan_lock); + if (list_empty(&scanning_hosts)) + complete(&data->prev_finished); + list_add_tail(&data->list, &scanning_hosts); + spin_unlock(&async_scan_lock); + + return data; + + err: + kfree(data); + return NULL; +} + +/** + * scsi_finish_async_scan - asynchronous scan has finished + * @data: cookie returned from earlier call to scsi_prep_async_scan() + * + * All the devices currently attached to this host have been found. + * This function announces all the devices it has found to the rest + * of the system. + */ +static void scsi_finish_async_scan(struct async_scan_data *data) +{ + struct Scsi_Host *shost; + unsigned long flags; + + if (!data) + return; + + shost = data->shost; + + mutex_lock(&shost->scan_mutex); + + if (!shost->async_scan) { + printk("%s called twice for host %d", __FUNCTION__, + shost->host_no); + dump_stack(); + return; + } + + wait_for_completion(&data->prev_finished); + + scsi_sysfs_add_devices(shost); + + spin_lock_irqsave(shost->host_lock, flags); + shost->async_scan = 0; + spin_unlock_irqrestore(shost->host_lock, flags); + + mutex_unlock(&shost->scan_mutex); + + spin_lock(&async_scan_lock); + list_del(&data->list); + if (!list_empty(&scanning_hosts)) { + struct async_scan_data *next = list_entry(scanning_hosts.next, + struct async_scan_data, list); + complete(&next->prev_finished); + } + spin_unlock(&async_scan_lock); + + scsi_host_put(shost); + kfree(data); +} + +static void do_scsi_scan_host(struct Scsi_Host *shost) +{ + if (shost->hostt->scan_finished) { + unsigned long start = jiffies; + if (shost->hostt->scan_start) + shost->hostt->scan_start(shost); + + while (!shost->hostt->scan_finished(shost, jiffies - start)) + msleep(10); + } else { + scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD, + SCAN_WILD_CARD, 0); + } +} + +static int do_scan_async(void *_data) +{ + struct async_scan_data *data = _data; + do_scsi_scan_host(data->shost); + scsi_finish_async_scan(data); + 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); + struct async_scan_data *data; + + if (strncmp(scsi_scan_type, "none", 4) == 0) + return; + + data = scsi_prep_async_scan(shost); + if (!data) { + do_scsi_scan_host(shost); + return; + } + + kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no); } EXPORT_SYMBOL(scsi_scan_host);