1 files changed, 816 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
new file mode 100644
index 000000000000..134d3a3e4222
--- /dev/null
+++ b/drivers/scsi/scsi_sysfs.c
@@ -0,0 +1,816 @@
+/*
+ * scsi_sysfs.c
+ *
+ * SCSI sysfs interface routines.
+ *
+ * Created to pull SCSI mid layer sysfs routines into one file.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <linux/device.h>
+
+#include <scsi/scsi.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_tcq.h>
+#include <scsi/scsi_transport.h>
+
+#include "scsi_priv.h"
+#include "scsi_logging.h"
+
+static struct {
+        enum scsi_device_state  value;
+        char                    *name;
+} sdev_states[] = {
+        { SDEV_CREATED, "created" },
+        { SDEV_RUNNING, "running" },
+        { SDEV_CANCEL, "cancel" },
+        { SDEV_DEL, "deleted" },
+        { SDEV_QUIESCE, "quiesce" },
+        { SDEV_OFFLINE, "offline" },
+        { SDEV_BLOCK,   "blocked" },
+};
+
+const char *scsi_device_state_name(enum scsi_device_state state)
+{
+        int i;
+        char *name = NULL;
+
+        for (i = 0; i < sizeof(sdev_states)/sizeof(sdev_states[0]); i++) {
+                if (sdev_states[i].value == state) {
+                        name = sdev_states[i].name;
+                        break;
+                }
+        }
+        return name;
+}
+
+static int check_set(unsigned int *val, char *src)
+{
+        char *last;
+
+        if (strncmp(src, "-", 20) == 0) {
+                *val = SCAN_WILD_CARD;
+        } else {
+                /*
+                 * Doesn't check for int overflow
+                 */
+                *val = simple_strtoul(src, &last, 0);
+                if (*last != '\0')
+                        return 1;
+        }
+        return 0;
+}
+
+static int scsi_scan(struct Scsi_Host *shost, const char *str)
+{
+        char s1[15], s2[15], s3[15], junk;
+        unsigned int channel, id, lun;
+        int res;
+
+        res = sscanf(str, "%10s %10s %10s %c", s1, s2, s3, &junk);
+        if (res != 3)
+                return -EINVAL;
+        if (check_set(&channel, s1))
+                return -EINVAL;
+        if (check_set(&id, s2))
+                return -EINVAL;
+        if (check_set(&lun, s3))
+                return -EINVAL;
+        res = scsi_scan_host_selected(shost, channel, id, lun, 1);
+        return res;
+}
+
+/*
+ * shost_show_function: macro to create an attr function that can be used to
+ * show a non-bit field.
+ */
+#define shost_show_function(name, field, format_string)                 \
+static ssize_t                                                          \
+show_##name (struct class_device *class_dev, char *buf)                 \
+{                                                                       \
+        struct Scsi_Host *shost = class_to_shost(class_dev);            \
+        return snprintf (buf, 20, format_string, shost->field);         \
+}
+
+/*
+ * shost_rd_attr: macro to create a function and attribute variable for a
+ * read only field.
+ */
+#define shost_rd_attr2(name, field, format_string)                      \
+        shost_show_function(name, field, format_string)                 \
+static CLASS_DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
+
+#define shost_rd_attr(field, format_string) \
+shost_rd_attr2(field, field, format_string)
+
+/*
+ * Create the actual show/store functions and data structures.
+ */
+
+static ssize_t store_scan(struct class_device *class_dev, const char *buf,
+                          size_t count)
+{
+        struct Scsi_Host *shost = class_to_shost(class_dev);
+        int res;
+
+        res = scsi_scan(shost, buf);
+        if (res == 0)
+                res = count;
+        return res;
+};
+static CLASS_DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
+
+shost_rd_attr(unique_id, "%u\n");
+shost_rd_attr(host_busy, "%hu\n");
+shost_rd_attr(cmd_per_lun, "%hd\n");
+shost_rd_attr(sg_tablesize, "%hu\n");
+shost_rd_attr(unchecked_isa_dma, "%d\n");
+shost_rd_attr2(proc_name, hostt->proc_name, "%s\n");
+
+static struct class_device_attribute *scsi_sysfs_shost_attrs[] = {
+        &class_device_attr_unique_id,
+        &class_device_attr_host_busy,
+        &class_device_attr_cmd_per_lun,
+        &class_device_attr_sg_tablesize,
+        &class_device_attr_unchecked_isa_dma,
+        &class_device_attr_proc_name,
+        &class_device_attr_scan,
+        NULL
+};
+
+static void scsi_device_cls_release(struct class_device *class_dev)
+{
+        struct scsi_device *sdev;
+
+        sdev = class_to_sdev(class_dev);
+        put_device(&sdev->sdev_gendev);
+}
+
+void scsi_device_dev_release(struct device *dev)
+{
+        struct scsi_device *sdev;
+        struct device *parent;
+        struct scsi_target *starget;
+        unsigned long flags;
+
+        parent = dev->parent;
+        sdev = to_scsi_device(dev);
+        starget = to_scsi_target(parent);
+
+        spin_lock_irqsave(sdev->host->host_lock, flags);
+        starget->reap_ref++;
+        list_del(&sdev->siblings);
+        list_del(&sdev->same_target_siblings);
+        list_del(&sdev->starved_entry);
+        spin_unlock_irqrestore(sdev->host->host_lock, flags);
+
+        if (sdev->request_queue) {
+                sdev->request_queue->queuedata = NULL;
+                scsi_free_queue(sdev->request_queue);
+        }
+
+        scsi_target_reap(scsi_target(sdev));
+
+        kfree(sdev->inquiry);
+        kfree(sdev);
+
+        if (parent)
+                put_device(parent);
+}
+
+struct class sdev_class = {
+        .name           = "scsi_device",
+        .release        = scsi_device_cls_release,
+};
+
+/* all probing is done in the individual ->probe routines */
+static int scsi_bus_match(struct device *dev, struct device_driver *gendrv)
+{
+        struct scsi_device *sdp = to_scsi_device(dev);
+        if (sdp->no_uld_attach)
+                return 0;
+        return (sdp->inq_periph_qual == SCSI_INQ_PQ_CON)? 1: 0;
+}
+
+struct bus_type scsi_bus_type = {
+        .name           = "scsi",
+        .match          = scsi_bus_match,
+};
+
+int scsi_sysfs_register(void)
+{
+        int error;
+
+        error = bus_register(&scsi_bus_type);
+        if (!error) {
+                error = class_register(&sdev_class);
+                if (error)
+                        bus_unregister(&scsi_bus_type);
+        }
+
+        return error;
+}
+
+void scsi_sysfs_unregister(void)
+{
+        class_unregister(&sdev_class);
+        bus_unregister(&scsi_bus_type);
+}
+
+/*
+ * sdev_show_function: macro to create an attr function that can be used to
+ * show a non-bit field.
+ */
+#define sdev_show_function(field, format_string)                                \
+static ssize_t                                                          \
+sdev_show_##field (struct device *dev, char *buf)                               \
+{                                                                       \
+        struct scsi_device *sdev;                                       \
+        sdev = to_scsi_device(dev);                                     \
+        return snprintf (buf, 20, format_string, sdev->field);          \
+}                                                                       \
+
+/*
+ * sdev_rd_attr: macro to create a function and attribute variable for a
+ * read only field.
+ */
+#define sdev_rd_attr(field, format_string)                              \
+        sdev_show_function(field, format_string)                        \
+static DEVICE_ATTR(field, S_IRUGO, sdev_show_##field, NULL);
+
+
+/*
+ * sdev_rd_attr: create a function and attribute variable for a
+ * read/write field.
+ */
+#define sdev_rw_attr(field, format_string)                              \
+        sdev_show_function(field, format_string)                                \
+                                                                        \
+static ssize_t                                                          \
+sdev_store_##field (struct device *dev, const char *buf, size_t count)  \
+{                                                                       \
+        struct scsi_device *sdev;                                       \
+        sdev = to_scsi_device(dev);                                     \
+        snscanf (buf, 20, format_string, &sdev->field);                 \
+        return count;                                                   \
+}                                                                       \
+static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
+
+/* Currently we don't export bit fields, but we might in future,
+ * so leave this code in */
+#if 0
+/*
+ * sdev_rd_attr: create a function and attribute variable for a
+ * read/write bit field.
+ */
+#define sdev_rw_attr_bit(field)                                         \
+        sdev_show_function(field, "%d\n")                                       \
+                                                                        \
+static ssize_t                                                          \
+sdev_store_##field (struct device *dev, const char *buf, size_t count)  \
+{                                                                       \
+        int ret;                                                        \
+        struct scsi_device *sdev;                                       \
+        ret = scsi_sdev_check_buf_bit(buf);                             \
+        if (ret >= 0)   {                                               \
+                sdev = to_scsi_device(dev);                             \
+                sdev->field = ret;                                      \
+                ret = count;                                            \
+        }                                                               \
+        return ret;                                                     \
+}                                                                       \
+static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field);
+
+/*
+ * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1",
+ * else return -EINVAL.
+ */
+static int scsi_sdev_check_buf_bit(const char *buf)
+{
+        if ((buf[1] == '\0') || ((buf[1] == '\n') && (buf[2] == '\0'))) {
+                if (buf[0] == '1')
+                        return 1;
+                else if (buf[0] == '0')
+                        return 0;
+                else 
+                        return -EINVAL;
+        } else
+                return -EINVAL;
+}
+#endif
+/*
+ * Create the actual show/store functions and data structures.
+ */
+sdev_rd_attr (device_blocked, "%d\n");
+sdev_rd_attr (queue_depth, "%d\n");
+sdev_rd_attr (type, "%d\n");
+sdev_rd_attr (scsi_level, "%d\n");
+sdev_rd_attr (vendor, "%.8s\n");
+sdev_rd_attr (model, "%.16s\n");
+sdev_rd_attr (rev, "%.4s\n");
+
+static ssize_t
+sdev_show_timeout (struct device *dev, char *buf)
+{
+        struct scsi_device *sdev;
+        sdev = to_scsi_device(dev);
+        return snprintf (buf, 20, "%d\n", sdev->timeout / HZ);
+}
+
+static ssize_t
+sdev_store_timeout (struct device *dev, const char *buf, size_t count)
+{
+        struct scsi_device *sdev;
+        int timeout;
+        sdev = to_scsi_device(dev);
+        sscanf (buf, "%d\n", &timeout);
+        sdev->timeout = timeout * HZ;
+        return count;
+}
+static DEVICE_ATTR(timeout, S_IRUGO | S_IWUSR, sdev_show_timeout, sdev_store_timeout);
+
+static ssize_t
+store_rescan_field (struct device *dev, const char *buf, size_t count) 
+{
+        scsi_rescan_device(dev);
+        return count;
+}
+static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
+
+static ssize_t sdev_store_delete(struct device *dev, const char *buf,
+                                 size_t count)
+{
+        scsi_remove_device(to_scsi_device(dev));
+        return count;
+};
+static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
+
+static ssize_t
+store_state_field(struct device *dev, const char *buf, size_t count)
+{
+        int i;
+        struct scsi_device *sdev = to_scsi_device(dev);
+        enum scsi_device_state state = 0;
+
+        for (i = 0; i < sizeof(sdev_states)/sizeof(sdev_states[0]); i++) {
+                const int len = strlen(sdev_states[i].name);
+                if (strncmp(sdev_states[i].name, buf, len) == 0 &&
+                   buf[len] == '\n') {
+                        state = sdev_states[i].value;
+                        break;
+                }
+        }
+        if (!state)
+                return -EINVAL;
+
+        if (scsi_device_set_state(sdev, state))
+                return -EINVAL;
+        return count;
+}
+
+static ssize_t
+show_state_field(struct device *dev, char *buf)
+{
+        struct scsi_device *sdev = to_scsi_device(dev);
+        const char *name = scsi_device_state_name(sdev->sdev_state);
+
+        if (!name)
+                return -EINVAL;
+
+        return snprintf(buf, 20, "%s\n", name);
+}
+
+static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, show_state_field, store_state_field);
+
+static ssize_t
+show_queue_type_field(struct device *dev, char *buf)
+{
+        struct scsi_device *sdev = to_scsi_device(dev);
+        const char *name = "none";
+
+        if (sdev->ordered_tags)
+                name = "ordered";
+        else if (sdev->simple_tags)
+                name = "simple";
+
+        return snprintf(buf, 20, "%s\n", name);
+}
+
+static DEVICE_ATTR(queue_type, S_IRUGO, show_queue_type_field, NULL);
+
+static ssize_t
+show_iostat_counterbits(struct device *dev, char *buf)
+{
+        return snprintf(buf, 20, "%d\n", (int)sizeof(atomic_t) * 8);
+}
+
+static DEVICE_ATTR(iocounterbits, S_IRUGO, show_iostat_counterbits, NULL);
+
+#define show_sdev_iostat(field)                                         \
+static ssize_t                                                          \
+show_iostat_##field(struct device *dev, char *buf)                      \
+{                                                                       \
+        struct scsi_device *sdev = to_scsi_device(dev);                 \
+        unsigned long long count = atomic_read(&sdev->field);           \
+        return snprintf(buf, 20, "0x%llx\n", count);                    \
+}                                                                       \
+static DEVICE_ATTR(field, S_IRUGO, show_iostat_##field, NULL)
+
+show_sdev_iostat(iorequest_cnt);
+show_sdev_iostat(iodone_cnt);
+show_sdev_iostat(ioerr_cnt);
+
+
+/* Default template for device attributes.  May NOT be modified */
+static struct device_attribute *scsi_sysfs_sdev_attrs[] = {
+        &dev_attr_device_blocked,
+        &dev_attr_queue_depth,
+        &dev_attr_queue_type,
+        &dev_attr_type,
+        &dev_attr_scsi_level,
+        &dev_attr_vendor,
+        &dev_attr_model,
+        &dev_attr_rev,
+        &dev_attr_rescan,
+        &dev_attr_delete,
+        &dev_attr_state,
+        &dev_attr_timeout,
+        &dev_attr_iocounterbits,
+        &dev_attr_iorequest_cnt,
+        &dev_attr_iodone_cnt,
+        &dev_attr_ioerr_cnt,
+        NULL
+};
+
+static ssize_t sdev_store_queue_depth_rw(struct device *dev, const char *buf,
+                                         size_t count)
+{
+        int depth, retval;
+        struct scsi_device *sdev = to_scsi_device(dev);
+        struct scsi_host_template *sht = sdev->host->hostt;
+
+        if (!sht->change_queue_depth)
+                return -EINVAL;
+
+        depth = simple_strtoul(buf, NULL, 0);
+
+        if (depth < 1)
+                return -EINVAL;
+
+        retval = sht->change_queue_depth(sdev, depth);
+        if (retval < 0)
+                return retval;
+
+        return count;
+}
+
+static struct device_attribute sdev_attr_queue_depth_rw =
+        __ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth,
+               sdev_store_queue_depth_rw);
+
+static ssize_t sdev_store_queue_type_rw(struct device *dev, const char *buf,
+                                        size_t count)
+{
+        struct scsi_device *sdev = to_scsi_device(dev);
+        struct scsi_host_template *sht = sdev->host->hostt;
+        int tag_type = 0, retval;
+        int prev_tag_type = scsi_get_tag_type(sdev);
+
+        if (!sdev->tagged_supported || !sht->change_queue_type)
+                return -EINVAL;
+
+        if (strncmp(buf, "ordered", 7) == 0)
+                tag_type = MSG_ORDERED_TAG;
+        else if (strncmp(buf, "simple", 6) == 0)
+                tag_type = MSG_SIMPLE_TAG;
+        else if (strncmp(buf, "none", 4) != 0)
+                return -EINVAL;
+
+        if (tag_type == prev_tag_type)
+                return count;
+
+        retval = sht->change_queue_type(sdev, tag_type);
+        if (retval < 0)
+                return retval;
+
+        return count;
+}
+
+static struct device_attribute sdev_attr_queue_type_rw =
+        __ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field,
+               sdev_store_queue_type_rw);
+
+static struct device_attribute *attr_changed_internally(
+                struct Scsi_Host *shost,
+                struct device_attribute * attr)
+{
+        if (!strcmp("queue_depth", attr->attr.name)
+            && shost->hostt->change_queue_depth)
+                return &sdev_attr_queue_depth_rw;
+        else if (!strcmp("queue_type", attr->attr.name)
+            && shost->hostt->change_queue_type)
+                return &sdev_attr_queue_type_rw;
+        return attr;
+}
+
+
+static struct device_attribute *attr_overridden(
+                struct device_attribute **attrs,
+                struct device_attribute *attr)
+{
+        int i;
+
+        if (!attrs)
+                return NULL;
+        for (i = 0; attrs[i]; i++)
+                if (!strcmp(attrs[i]->attr.name, attr->attr.name))
+                        return attrs[i];
+        return NULL;
+}
+
+static int attr_add(struct device *dev, struct device_attribute *attr)
+{
+        struct device_attribute *base_attr;
+
+        /*
+         * Spare the caller from having to copy things it's not interested in.
+         */
+        base_attr = attr_overridden(scsi_sysfs_sdev_attrs, attr);
+        if (base_attr) {
+                /* extend permissions */
+                attr->attr.mode |= base_attr->attr.mode;
+
+                /* override null show/store with default */
+                if (!attr->show)
+                        attr->show = base_attr->show;
+                if (!attr->store)
+                        attr->store = base_attr->store;
+        }
+
+        return device_create_file(dev, attr);
+}
+
+/**
+ * scsi_sysfs_add_sdev - add scsi device to sysfs
+ * @sdev:       scsi_device to add
+ *
+ * Return value:
+ *      0 on Success / non-zero on Failure
+ **/
+int scsi_sysfs_add_sdev(struct scsi_device *sdev)
+{
+        int error, i;
+
+        if ((error = scsi_device_set_state(sdev, SDEV_RUNNING)) != 0)
+                return error;
+
+        error = device_add(&sdev->sdev_gendev);
+        if (error) {
+                put_device(sdev->sdev_gendev.parent);
+                printk(KERN_INFO "error 1\n");
+                return error;
+        }
+        error = class_device_add(&sdev->sdev_classdev);
+        if (error) {
+                printk(KERN_INFO "error 2\n");
+                goto clean_device;
+        }
+
+        /* take a reference for the sdev_classdev; this is
+         * released by the sdev_class .release */
+        get_device(&sdev->sdev_gendev);
+        if (sdev->host->hostt->sdev_attrs) {
+                for (i = 0; sdev->host->hostt->sdev_attrs[i]; i++) {
+                        error = attr_add(&sdev->sdev_gendev,
+                                        sdev->host->hostt->sdev_attrs[i]);
+                        if (error) {
+                                scsi_remove_device(sdev);
+                                goto out;
+                        }
+                }
+        }
+        
+        for (i = 0; scsi_sysfs_sdev_attrs[i]; i++) {
+                if (!attr_overridden(sdev->host->hostt->sdev_attrs,
+                                        scsi_sysfs_sdev_attrs[i])) {
+                        struct device_attribute * attr = 
+                                attr_changed_internally(sdev->host, 
+                                                        scsi_sysfs_sdev_attrs[i]);
+                        error = device_create_file(&sdev->sdev_gendev, attr);
+                        if (error) {
+                                scsi_remove_device(sdev);
+                                goto out;
+                        }
+                }
+        }
+
+        transport_add_device(&sdev->sdev_gendev);
+ out:
+        return error;
+
+ clean_device:
+        scsi_device_set_state(sdev, SDEV_CANCEL);
+
+        device_del(&sdev->sdev_gendev);
+        transport_destroy_device(&sdev->sdev_gendev);
+        put_device(&sdev->sdev_gendev);
+
+        return error;
+}
+
+/**
+ * scsi_remove_device - unregister a device from the scsi bus
+ * @sdev:       scsi_device to unregister
+ **/
+void scsi_remove_device(struct scsi_device *sdev)
+{
+        struct Scsi_Host *shost = sdev->host;
+
+        down(&shost->scan_mutex);
+        if (scsi_device_set_state(sdev, SDEV_CANCEL) != 0)
+                goto out;
+
+        class_device_unregister(&sdev->sdev_classdev);
+        device_del(&sdev->sdev_gendev);
+        scsi_device_set_state(sdev, SDEV_DEL);
+        if (sdev->host->hostt->slave_destroy)
+                sdev->host->hostt->slave_destroy(sdev);
+        transport_unregister_device(&sdev->sdev_gendev);
+        put_device(&sdev->sdev_gendev);
+out:
+        up(&shost->scan_mutex);
+}
+EXPORT_SYMBOL(scsi_remove_device);
+
+void __scsi_remove_target(struct scsi_target *starget)
+{
+        struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
+        unsigned long flags;
+        struct scsi_device *sdev, *tmp;
+
+        spin_lock_irqsave(shost->host_lock, flags);
+        starget->reap_ref++;
+        list_for_each_entry_safe(sdev, tmp, &shost->__devices, siblings) {
+                if (sdev->channel != starget->channel ||
+                    sdev->id != starget->id)
+                        continue;
+                spin_unlock_irqrestore(shost->host_lock, flags);
+                scsi_remove_device(sdev);
+                spin_lock_irqsave(shost->host_lock, flags);
+        }
+        spin_unlock_irqrestore(shost->host_lock, flags);
+        scsi_target_reap(starget);
+}
+
+/**
+ * scsi_remove_target - try to remove a target and all its devices
+ * @dev: generic starget or parent of generic stargets to be removed
+ *
+ * Note: This is slightly racy.  It is possible that if the user
+ * requests the addition of another device then the target won't be
+ * removed.
+ */
+void scsi_remove_target(struct device *dev)
+{
+        struct device *rdev, *idev, *next;
+
+        if (scsi_is_target_device(dev)) {
+                __scsi_remove_target(to_scsi_target(dev));
+                return;
+        }
+
+        rdev = get_device(dev);
+        list_for_each_entry_safe(idev, next, &dev->children, node) {
+                if (scsi_is_target_device(idev))
+                        __scsi_remove_target(to_scsi_target(idev));
+        }
+        put_device(rdev);
+}
+EXPORT_SYMBOL(scsi_remove_target);
+
+int scsi_register_driver(struct device_driver *drv)
+{
+        drv->bus = &scsi_bus_type;
+
+        return driver_register(drv);
+}
+EXPORT_SYMBOL(scsi_register_driver);
+
+int scsi_register_interface(struct class_interface *intf)
+{
+        intf->class = &sdev_class;
+
+        return class_interface_register(intf);
+}
+EXPORT_SYMBOL(scsi_register_interface);
+
+
+static struct class_device_attribute *class_attr_overridden(
+                struct class_device_attribute **attrs,
+                struct class_device_attribute *attr)
+{
+        int i;
+
+        if (!attrs)
+                return NULL;
+        for (i = 0; attrs[i]; i++)
+                if (!strcmp(attrs[i]->attr.name, attr->attr.name))
+                        return attrs[i];
+        return NULL;
+}
+
+static int class_attr_add(struct class_device *classdev,
+                struct class_device_attribute *attr)
+{
+        struct class_device_attribute *base_attr;
+
+        /*
+         * Spare the caller from having to copy things it's not interested in.
+         */
+        base_attr = class_attr_overridden(scsi_sysfs_shost_attrs, attr);
+        if (base_attr) {
+                /* extend permissions */
+                attr->attr.mode |= base_attr->attr.mode;
+
+                /* override null show/store with default */
+                if (!attr->show)
+                        attr->show = base_attr->show;
+                if (!attr->store)
+                        attr->store = base_attr->store;
+        }
+
+        return class_device_create_file(classdev, attr);
+}
+
+/**
+ * scsi_sysfs_add_host - add scsi host to subsystem
+ * @shost:     scsi host struct to add to subsystem
+ * @dev:       parent struct device pointer
+ **/
+int scsi_sysfs_add_host(struct Scsi_Host *shost)
+{
+        int error, i;
+
+        if (shost->hostt->shost_attrs) {
+                for (i = 0; shost->hostt->shost_attrs[i]; i++) {
+                        error = class_attr_add(&shost->shost_classdev,
+                                        shost->hostt->shost_attrs[i]);
+                        if (error)
+                                return error;
+                }
+        }
+
+        for (i = 0; scsi_sysfs_shost_attrs[i]; i++) {
+                if (!class_attr_overridden(shost->hostt->shost_attrs,
+                                        scsi_sysfs_shost_attrs[i])) {
+                        error = class_device_create_file(&shost->shost_classdev,
+                                        scsi_sysfs_shost_attrs[i]);
+                        if (error)
+                                return error;
+                }
+        }
+
+        transport_register_device(&shost->shost_gendev);
+        return 0;
+}
+
+void scsi_sysfs_device_initialize(struct scsi_device *sdev)
+{
+        unsigned long flags;
+        struct Scsi_Host *shost = sdev->host;
+        struct scsi_target  *starget = sdev->sdev_target;
+
+        device_initialize(&sdev->sdev_gendev);
+        sdev->sdev_gendev.bus = &scsi_bus_type;
+        sdev->sdev_gendev.release = scsi_device_dev_release;
+        sprintf(sdev->sdev_gendev.bus_id,"%d:%d:%d:%d",
+                sdev->host->host_no, sdev->channel, sdev->id,
+                sdev->lun);
+        
+        class_device_initialize(&sdev->sdev_classdev);
+        sdev->sdev_classdev.dev = &sdev->sdev_gendev;
+        sdev->sdev_classdev.class = &sdev_class;
+        snprintf(sdev->sdev_classdev.class_id, BUS_ID_SIZE,
+                 "%d:%d:%d:%d", sdev->host->host_no,
+                 sdev->channel, sdev->id, sdev->lun);
+        sdev->scsi_level = SCSI_2;
+        transport_setup_device(&sdev->sdev_gendev);
+        spin_lock_irqsave(shost->host_lock, flags);
+        list_add_tail(&sdev->same_target_siblings, &starget->devices);
+        list_add_tail(&sdev->siblings, &shost->__devices);
+        spin_unlock_irqrestore(shost->host_lock, flags);
+}
+
+int scsi_is_sdev_device(const struct device *dev)
+{
+        return dev->release == scsi_device_dev_release;
+}
+EXPORT_SYMBOL(scsi_is_sdev_device);
+
+/* A blank transport template that is used in drivers that don't
+ * yet implement Transport Attributes */
+struct scsi_transport_template blank_transport_template = { { { {NULL, }, }, }, };