[SCSI] scsi_transport_sas: don't scan a non-existent end device

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / scsi / scsi_transport_sas.c

/*
 * Copyright (C) 2005-2006 Dell Inc.
 *      Released under GPL v2.
 *
 * Serial Attached SCSI (SAS) transport class.
 *
 * The SAS transport class contains common code to deal with SAS HBAs,
 * an aproximated representation of SAS topologies in the driver model,
 * and various sysfs attributes to expose these topologies and managment
 * interfaces to userspace.
 *
 * In addition to the basic SCSI core objects this transport class
 * introduces two additional intermediate objects:  The SAS PHY
 * as represented by struct sas_phy defines an "outgoing" PHY on
 * a SAS HBA or Expander, and the SAS remote PHY represented by
 * struct sas_rphy defines an "incoming" PHY on a SAS Expander or
 * end device.  Note that this is purely a software concept, the
 * underlying hardware for a PHY and a remote PHY is the exactly
 * the same.
 *
 * There is no concept of a SAS port in this code, users can see
 * what PHYs form a wide port based on the port_identifier attribute,
 * which is the same for all PHYs in a port.
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>

#include <scsi/scsi.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>

#include "scsi_sas_internal.h"
struct sas_host_attrs {
        struct list_head rphy_list;
        struct mutex lock;
        u32 next_target_id;
        u32 next_expander_id;
};
#define to_sas_host_attrs(host) ((struct sas_host_attrs *)(host)->shost_data)


/*
 * Hack to allow attributes of the same name in different objects.
 */
#define SAS_CLASS_DEVICE_ATTR(_prefix,_name,_mode,_show,_store) \
        struct class_device_attribute class_device_attr_##_prefix##_##_name = \
        __ATTR(_name,_mode,_show,_store)


/*
 * Pretty printing helpers
 */

#define sas_bitfield_name_match(title, table)                   \
static ssize_t                                                  \
get_sas_##title##_names(u32 table_key, char *buf)               \
{                                                               \
        char *prefix = "";                                      \
        ssize_t len = 0;                                        \
        int i;                                                  \
                                                                \
        for (i = 0; i < sizeof(table)/sizeof(table[0]); i++) {  \
                if (table[i].value & table_key) {               \
                        len += sprintf(buf + len, "%s%s",       \
                                prefix, table[i].name);         \
                        prefix = ", ";                          \
                }                                               \
        }                                                       \
        len += sprintf(buf + len, "\n");                        \
        return len;                                             \
}

#define sas_bitfield_name_search(title, table)                  \
static ssize_t                                                  \
get_sas_##title##_names(u32 table_key, char *buf)               \
{                                                               \
        ssize_t len = 0;                                        \
        int i;                                                  \
                                                                \
        for (i = 0; i < sizeof(table)/sizeof(table[0]); i++) {  \
                if (table[i].value == table_key) {              \
                        len += sprintf(buf + len, "%s",         \
                                table[i].name);                 \
                        break;                                  \
                }                                               \
        }                                                       \
        len += sprintf(buf + len, "\n");                        \
        return len;                                             \
}

static struct {
        u32             value;
        char            *name;
} sas_device_type_names[] = {
        { SAS_PHY_UNUSED,               "unused" },
        { SAS_END_DEVICE,               "end device" },
        { SAS_EDGE_EXPANDER_DEVICE,     "edge expander" },
        { SAS_FANOUT_EXPANDER_DEVICE,   "fanout expander" },
};
sas_bitfield_name_search(device_type, sas_device_type_names)


static struct {
        u32             value;
        char            *name;
} sas_protocol_names[] = {
        { SAS_PROTOCOL_SATA,            "sata" },
        { SAS_PROTOCOL_SMP,             "smp" },
        { SAS_PROTOCOL_STP,             "stp" },
        { SAS_PROTOCOL_SSP,             "ssp" },
};
sas_bitfield_name_match(protocol, sas_protocol_names)

static struct {
        u32             value;
        char            *name;
} sas_linkspeed_names[] = {
        { SAS_LINK_RATE_UNKNOWN,        "Unknown" },
        { SAS_PHY_DISABLED,             "Phy disabled" },
        { SAS_LINK_RATE_FAILED,         "Link Rate failed" },
        { SAS_SATA_SPINUP_HOLD,         "Spin-up hold" },
        { SAS_LINK_RATE_1_5_GBPS,       "1.5 Gbit" },
        { SAS_LINK_RATE_3_0_GBPS,       "3.0 Gbit" },
        { SAS_LINK_RATE_6_0_GBPS,       "6.0 Gbit" },
};
sas_bitfield_name_search(linkspeed, sas_linkspeed_names)


/*
 * SAS host attributes
 */

static int sas_host_setup(struct transport_container *tc, struct device *dev,
                          struct class_device *cdev)
{
        struct Scsi_Host *shost = dev_to_shost(dev);
        struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);

        INIT_LIST_HEAD(&sas_host->rphy_list);
        mutex_init(&sas_host->lock);
        sas_host->next_target_id = 0;
        sas_host->next_expander_id = 0;
        return 0;
}

static DECLARE_TRANSPORT_CLASS(sas_host_class,
                "sas_host", sas_host_setup, NULL, NULL);

static int sas_host_match(struct attribute_container *cont,
                            struct device *dev)
{
        struct Scsi_Host *shost;
        struct sas_internal *i;

        if (!scsi_is_host_device(dev))
                return 0;
        shost = dev_to_shost(dev);

        if (!shost->transportt)
                return 0;
        if (shost->transportt->host_attrs.ac.class !=
                        &sas_host_class.class)
                return 0;

        i = to_sas_internal(shost->transportt);
        return &i->t.host_attrs.ac == cont;
}

static int do_sas_phy_delete(struct device *dev, void *data)
{
        if (scsi_is_sas_phy(dev))
                sas_phy_delete(dev_to_phy(dev));
        return 0;
}

/**
 * sas_remove_host  --  tear down a Scsi_Host's SAS data structures
 * @shost:      Scsi Host that is torn down
 *
 * Removes all SAS PHYs and remote PHYs for a given Scsi_Host.
 * Must be called just before scsi_remove_host for SAS HBAs.
 */
void sas_remove_host(struct Scsi_Host *shost)
{
        device_for_each_child(&shost->shost_gendev, NULL, do_sas_phy_delete);
}
EXPORT_SYMBOL(sas_remove_host);


/*
 * SAS Port attributes
 */

#define sas_phy_show_simple(field, name, format_string, cast)           \
static ssize_t                                                          \
show_sas_phy_##name(struct class_device *cdev, char *buf)               \
{                                                                       \
        struct sas_phy *phy = transport_class_to_phy(cdev);             \
                                                                        \
        return snprintf(buf, 20, format_string, cast phy->field);       \
}

#define sas_phy_simple_attr(field, name, format_string, type)           \
        sas_phy_show_simple(field, name, format_string, (type)) \
static CLASS_DEVICE_ATTR(name, S_IRUGO, show_sas_phy_##name, NULL)

#define sas_phy_show_protocol(field, name)                              \
static ssize_t                                                          \
show_sas_phy_##name(struct class_device *cdev, char *buf)               \
{                                                                       \
        struct sas_phy *phy = transport_class_to_phy(cdev);             \
                                                                        \
        if (!phy->field)                                                \
                return snprintf(buf, 20, "none\n");                     \
        return get_sas_protocol_names(phy->field, buf);         \
}

#define sas_phy_protocol_attr(field, name)                              \
        sas_phy_show_protocol(field, name)                              \
static CLASS_DEVICE_ATTR(name, S_IRUGO, show_sas_phy_##name, NULL)

#define sas_phy_show_linkspeed(field)                                   \
static ssize_t                                                          \
show_sas_phy_##field(struct class_device *cdev, char *buf)              \
{                                                                       \
        struct sas_phy *phy = transport_class_to_phy(cdev);             \
                                                                        \
        return get_sas_linkspeed_names(phy->field, buf);                \
}

#define sas_phy_linkspeed_attr(field)                                   \
        sas_phy_show_linkspeed(field)                                   \
static CLASS_DEVICE_ATTR(field, S_IRUGO, show_sas_phy_##field, NULL)

#define sas_phy_show_linkerror(field)                                   \
static ssize_t                                                          \
show_sas_phy_##field(struct class_device *cdev, char *buf)              \
{                                                                       \
        struct sas_phy *phy = transport_class_to_phy(cdev);             \
        struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);        \
        struct sas_internal *i = to_sas_internal(shost->transportt);    \
        int error;                                                      \
                                                                        \
        if (!phy->local_attached)                                       \
                return -EINVAL;                                         \
                                                                        \
        error = i->f->get_linkerrors ? i->f->get_linkerrors(phy) : 0;   \
        if (error)                                                      \
                return error;                                           \
        return snprintf(buf, 20, "%u\n", phy->field);                   \
}

#define sas_phy_linkerror_attr(field)                                   \
        sas_phy_show_linkerror(field)                                   \
static CLASS_DEVICE_ATTR(field, S_IRUGO, show_sas_phy_##field, NULL)


static ssize_t
show_sas_device_type(struct class_device *cdev, char *buf)
{
        struct sas_phy *phy = transport_class_to_phy(cdev);

        if (!phy->identify.device_type)
                return snprintf(buf, 20, "none\n");
        return get_sas_device_type_names(phy->identify.device_type, buf);
}
static CLASS_DEVICE_ATTR(device_type, S_IRUGO, show_sas_device_type, NULL);

static ssize_t do_sas_phy_reset(struct class_device *cdev,
                size_t count, int hard_reset)
{
        struct sas_phy *phy = transport_class_to_phy(cdev);
        struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
        struct sas_internal *i = to_sas_internal(shost->transportt);
        int error;

        if (!phy->local_attached)
                return -EINVAL;

        error = i->f->phy_reset(phy, hard_reset);
        if (error)
                return error;
        return count;
};

static ssize_t store_sas_link_reset(struct class_device *cdev,
                const char *buf, size_t count)
{
        return do_sas_phy_reset(cdev, count, 0);
}
static CLASS_DEVICE_ATTR(link_reset, S_IWUSR, NULL, store_sas_link_reset);

static ssize_t store_sas_hard_reset(struct class_device *cdev,
                const char *buf, size_t count)
{
        return do_sas_phy_reset(cdev, count, 1);
}
static CLASS_DEVICE_ATTR(hard_reset, S_IWUSR, NULL, store_sas_hard_reset);

sas_phy_protocol_attr(identify.initiator_port_protocols,
                initiator_port_protocols);
sas_phy_protocol_attr(identify.target_port_protocols,
                target_port_protocols);
sas_phy_simple_attr(identify.sas_address, sas_address, "0x%016llx\n",
                unsigned long long);
sas_phy_simple_attr(identify.phy_identifier, phy_identifier, "%d\n", u8);
sas_phy_simple_attr(port_identifier, port_identifier, "%d\n", u8);
sas_phy_linkspeed_attr(negotiated_linkrate);
sas_phy_linkspeed_attr(minimum_linkrate_hw);
sas_phy_linkspeed_attr(minimum_linkrate);
sas_phy_linkspeed_attr(maximum_linkrate_hw);
sas_phy_linkspeed_attr(maximum_linkrate);
sas_phy_linkerror_attr(invalid_dword_count);
sas_phy_linkerror_attr(running_disparity_error_count);
sas_phy_linkerror_attr(loss_of_dword_sync_count);
sas_phy_linkerror_attr(phy_reset_problem_count);


static DECLARE_TRANSPORT_CLASS(sas_phy_class,
                "sas_phy", NULL, NULL, NULL);

static int sas_phy_match(struct attribute_container *cont, struct device *dev)
{
        struct Scsi_Host *shost;
        struct sas_internal *i;

        if (!scsi_is_sas_phy(dev))
                return 0;
        shost = dev_to_shost(dev->parent);

        if (!shost->transportt)
                return 0;
        if (shost->transportt->host_attrs.ac.class !=
                        &sas_host_class.class)
                return 0;

        i = to_sas_internal(shost->transportt);
        return &i->phy_attr_cont.ac == cont;
}

static void sas_phy_release(struct device *dev)
{
        struct sas_phy *phy = dev_to_phy(dev);

        put_device(dev->parent);
        kfree(phy);
}

/**
 * sas_phy_alloc  --  allocates and initialize a SAS PHY structure
 * @parent:     Parent device
 * @number:     Phy index
 *
 * Allocates an SAS PHY structure.  It will be added in the device tree
 * below the device specified by @parent, which has to be either a Scsi_Host
 * or sas_rphy.
 *
 * Returns:
 *      SAS PHY allocated or %NULL if the allocation failed.
 */
struct sas_phy *sas_phy_alloc(struct device *parent, int number)
{
        struct Scsi_Host *shost = dev_to_shost(parent);
        struct sas_phy *phy;

        phy = kzalloc(sizeof(*phy), GFP_KERNEL);
        if (!phy)
                return NULL;

        phy->number = number;

        device_initialize(&phy->dev);
        phy->dev.parent = get_device(parent);
        phy->dev.release = sas_phy_release;
        if (scsi_is_sas_expander_device(parent)) {
                struct sas_rphy *rphy = dev_to_rphy(parent);
                sprintf(phy->dev.bus_id, "phy-%d-%d:%d", shost->host_no,
                        rphy->scsi_target_id, number);
        } else
                sprintf(phy->dev.bus_id, "phy-%d:%d", shost->host_no, number);

        transport_setup_device(&phy->dev);

        return phy;
}
EXPORT_SYMBOL(sas_phy_alloc);

/**
 * sas_phy_add  --  add a SAS PHY to the device hierachy
 * @phy:        The PHY to be added
 *
 * Publishes a SAS PHY to the rest of the system.
 */
int sas_phy_add(struct sas_phy *phy)
{
        int error;

        error = device_add(&phy->dev);
        if (!error) {
                transport_add_device(&phy->dev);
                transport_configure_device(&phy->dev);
        }

        return error;
}
EXPORT_SYMBOL(sas_phy_add);

/**
 * sas_phy_free  --  free a SAS PHY
 * @phy:        SAS PHY to free
 *
 * Frees the specified SAS PHY.
 *
 * Note:
 *   This function must only be called on a PHY that has not
 *   sucessfully been added using sas_phy_add().
 */
void sas_phy_free(struct sas_phy *phy)
{
        transport_destroy_device(&phy->dev);
        put_device(&phy->dev);
}
EXPORT_SYMBOL(sas_phy_free);

/**
 * sas_phy_delete  --  remove SAS PHY
 * @phy:        SAS PHY to remove
 *
 * Removes the specified SAS PHY.  If the SAS PHY has an
 * associated remote PHY it is removed before.
 */
void
sas_phy_delete(struct sas_phy *phy)
{
        struct device *dev = &phy->dev;

        if (phy->rphy)
                sas_rphy_delete(phy->rphy);

        transport_remove_device(dev);
        device_del(dev);
        transport_destroy_device(dev);
        put_device(dev);
}
EXPORT_SYMBOL(sas_phy_delete);

/**
 * scsi_is_sas_phy  --  check if a struct device represents a SAS PHY
 * @dev:        device to check
 *
 * Returns:
 *      %1 if the device represents a SAS PHY, %0 else
 */
int scsi_is_sas_phy(const struct device *dev)
{
        return dev->release == sas_phy_release;
}
EXPORT_SYMBOL(scsi_is_sas_phy);

/*
 * SAS remote PHY attributes.
 */

#define sas_rphy_show_simple(field, name, format_string, cast)          \
static ssize_t                                                          \
show_sas_rphy_##name(struct class_device *cdev, char *buf)              \
{                                                                       \
        struct sas_rphy *rphy = transport_class_to_rphy(cdev);  \
                                                                        \
        return snprintf(buf, 20, format_string, cast rphy->field);      \
}

#define sas_rphy_simple_attr(field, name, format_string, type)          \
        sas_rphy_show_simple(field, name, format_string, (type))        \
static SAS_CLASS_DEVICE_ATTR(rphy, name, S_IRUGO,                       \
                show_sas_rphy_##name, NULL)

#define sas_rphy_show_protocol(field, name)                             \
static ssize_t                                                          \
show_sas_rphy_##name(struct class_device *cdev, char *buf)              \
{                                                                       \
        struct sas_rphy *rphy = transport_class_to_rphy(cdev);  \
                                                                        \
        if (!rphy->field)                                       \
                return snprintf(buf, 20, "none\n");                     \
        return get_sas_protocol_names(rphy->field, buf);        \
}

#define sas_rphy_protocol_attr(field, name)                             \
        sas_rphy_show_protocol(field, name)                             \
static SAS_CLASS_DEVICE_ATTR(rphy, name, S_IRUGO,                       \
                show_sas_rphy_##name, NULL)

static ssize_t
show_sas_rphy_device_type(struct class_device *cdev, char *buf)
{
        struct sas_rphy *rphy = transport_class_to_rphy(cdev);

        if (!rphy->identify.device_type)
                return snprintf(buf, 20, "none\n");
        return get_sas_device_type_names(
                        rphy->identify.device_type, buf);
}

static SAS_CLASS_DEVICE_ATTR(rphy, device_type, S_IRUGO,
                show_sas_rphy_device_type, NULL);

static ssize_t
show_sas_rphy_enclosure_identifier(struct class_device *cdev, char *buf)
{
        struct sas_rphy *rphy = transport_class_to_rphy(cdev);
        struct sas_phy *phy = dev_to_phy(rphy->dev.parent);
        struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
        struct sas_internal *i = to_sas_internal(shost->transportt);
        u64 identifier;
        int error;

        /*
         * Only devices behind an expander are supported, because the
         * enclosure identifier is a SMP feature.
         */
        if (phy->local_attached)
                return -EINVAL;

        error = i->f->get_enclosure_identifier(rphy, &identifier);
        if (error)
                return error;
        return sprintf(buf, "0x%llx\n", (unsigned long long)identifier);
}

static SAS_CLASS_DEVICE_ATTR(rphy, enclosure_identifier, S_IRUGO,
                show_sas_rphy_enclosure_identifier, NULL);

static ssize_t
show_sas_rphy_bay_identifier(struct class_device *cdev, char *buf)
{
        struct sas_rphy *rphy = transport_class_to_rphy(cdev);
        struct sas_phy *phy = dev_to_phy(rphy->dev.parent);
        struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
        struct sas_internal *i = to_sas_internal(shost->transportt);
        int val;

        if (phy->local_attached)
                return -EINVAL;

        val = i->f->get_bay_identifier(rphy);
        if (val < 0)
                return val;
        return sprintf(buf, "%d\n", val);
}

static SAS_CLASS_DEVICE_ATTR(rphy, bay_identifier, S_IRUGO,
                show_sas_rphy_bay_identifier, NULL);

sas_rphy_protocol_attr(identify.initiator_port_protocols,
                initiator_port_protocols);
sas_rphy_protocol_attr(identify.target_port_protocols, target_port_protocols);
sas_rphy_simple_attr(identify.sas_address, sas_address, "0x%016llx\n",
                unsigned long long);
sas_rphy_simple_attr(identify.phy_identifier, phy_identifier, "%d\n", u8);

/* only need 8 bytes of data plus header (4 or 8) */
#define BUF_SIZE 64

int sas_read_port_mode_page(struct scsi_device *sdev)
{
        char *buffer = kzalloc(BUF_SIZE, GFP_KERNEL), *msdata;
        struct sas_rphy *rphy = target_to_rphy(sdev->sdev_target);
        struct sas_end_device *rdev;
        struct scsi_mode_data mode_data;
        int res, error;

        BUG_ON(rphy->identify.device_type != SAS_END_DEVICE);

        rdev = rphy_to_end_device(rphy);

        if (!buffer)
                return -ENOMEM;

        res = scsi_mode_sense(sdev, 1, 0x19, buffer, BUF_SIZE, 30*HZ, 3,
                              &mode_data, NULL);

        error = -EINVAL;
        if (!scsi_status_is_good(res))
                goto out;

        msdata = buffer +  mode_data.header_length +
                mode_data.block_descriptor_length;

        if (msdata - buffer > BUF_SIZE - 8)
                goto out;

        error = 0;

        rdev->ready_led_meaning = msdata[2] & 0x10 ? 1 : 0;
        rdev->I_T_nexus_loss_timeout = (msdata[4] << 8) + msdata[5];
        rdev->initiator_response_timeout = (msdata[6] << 8) + msdata[7];

 out:
        kfree(buffer);
        return error;
}
EXPORT_SYMBOL(sas_read_port_mode_page);

static DECLARE_TRANSPORT_CLASS(sas_end_dev_class,
                               "sas_end_device", NULL, NULL, NULL);

#define sas_end_dev_show_simple(field, name, format_string, cast)       \
static ssize_t                                                          \
show_sas_end_dev_##name(struct class_device *cdev, char *buf)           \
{                                                                       \
        struct sas_rphy *rphy = transport_class_to_rphy(cdev);          \
        struct sas_end_device *rdev = rphy_to_end_device(rphy);         \
                                                                        \
        return snprintf(buf, 20, format_string, cast rdev->field);      \
}

#define sas_end_dev_simple_attr(field, name, format_string, type)       \
        sas_end_dev_show_simple(field, name, format_string, (type))     \
static SAS_CLASS_DEVICE_ATTR(end_dev, name, S_IRUGO,                    \
                show_sas_end_dev_##name, NULL)

sas_end_dev_simple_attr(ready_led_meaning, ready_led_meaning, "%d\n", int);
sas_end_dev_simple_attr(I_T_nexus_loss_timeout, I_T_nexus_loss_timeout,
                        "%d\n", int);
sas_end_dev_simple_attr(initiator_response_timeout, initiator_response_timeout,
                        "%d\n", int);

static DECLARE_TRANSPORT_CLASS(sas_expander_class,
                               "sas_expander", NULL, NULL, NULL);

#define sas_expander_show_simple(field, name, format_string, cast)      \
static ssize_t                                                          \
show_sas_expander_##name(struct class_device *cdev, char *buf)          \
{                                                                       \
        struct sas_rphy *rphy = transport_class_to_rphy(cdev);          \
        struct sas_expander_device *edev = rphy_to_expander_device(rphy); \
                                                                        \
        return snprintf(buf, 20, format_string, cast edev->field);      \
}

#define sas_expander_simple_attr(field, name, format_string, type)      \
        sas_expander_show_simple(field, name, format_string, (type))    \
static SAS_CLASS_DEVICE_ATTR(expander, name, S_IRUGO,                   \
                show_sas_expander_##name, NULL)

sas_expander_simple_attr(vendor_id, vendor_id, "%s\n", char *);
sas_expander_simple_attr(product_id, product_id, "%s\n", char *);
sas_expander_simple_attr(product_rev, product_rev, "%s\n", char *);
sas_expander_simple_attr(component_vendor_id, component_vendor_id,
                         "%s\n", char *);
sas_expander_simple_attr(component_id, component_id, "%u\n", unsigned int);
sas_expander_simple_attr(component_revision_id, component_revision_id, "%u\n",
                         unsigned int);
sas_expander_simple_attr(level, level, "%d\n", int);

static DECLARE_TRANSPORT_CLASS(sas_rphy_class,
                "sas_device", NULL, NULL, NULL);

static int sas_rphy_match(struct attribute_container *cont, struct device *dev)
{
        struct Scsi_Host *shost;
        struct sas_internal *i;

        if (!scsi_is_sas_rphy(dev))
                return 0;
        shost = dev_to_shost(dev->parent->parent);

        if (!shost->transportt)
                return 0;
        if (shost->transportt->host_attrs.ac.class !=
                        &sas_host_class.class)
                return 0;

        i = to_sas_internal(shost->transportt);
        return &i->rphy_attr_cont.ac == cont;
}

static int sas_end_dev_match(struct attribute_container *cont,
                             struct device *dev)
{
        struct Scsi_Host *shost;
        struct sas_internal *i;
        struct sas_rphy *rphy;

        if (!scsi_is_sas_rphy(dev))
                return 0;
        shost = dev_to_shost(dev->parent->parent);
        rphy = dev_to_rphy(dev);

        if (!shost->transportt)
                return 0;
        if (shost->transportt->host_attrs.ac.class !=
                        &sas_host_class.class)
                return 0;

        i = to_sas_internal(shost->transportt);
        return &i->end_dev_attr_cont.ac == cont &&
                rphy->identify.device_type == SAS_END_DEVICE;
}

static int sas_expander_match(struct attribute_container *cont,
                              struct device *dev)
{
        struct Scsi_Host *shost;
        struct sas_internal *i;
        struct sas_rphy *rphy;

        if (!scsi_is_sas_rphy(dev))
                return 0;
        shost = dev_to_shost(dev->parent->parent);
        rphy = dev_to_rphy(dev);

        if (!shost->transportt)
                return 0;
        if (shost->transportt->host_attrs.ac.class !=
                        &sas_host_class.class)
                return 0;

        i = to_sas_internal(shost->transportt);
        return &i->expander_attr_cont.ac == cont &&
                (rphy->identify.device_type == SAS_EDGE_EXPANDER_DEVICE ||
                 rphy->identify.device_type == SAS_FANOUT_EXPANDER_DEVICE);
}

static void sas_expander_release(struct device *dev)
{
        struct sas_rphy *rphy = dev_to_rphy(dev);
        struct sas_expander_device *edev = rphy_to_expander_device(rphy);

        put_device(dev->parent);
        kfree(edev);
}

static void sas_end_device_release(struct device *dev)
{
        struct sas_rphy *rphy = dev_to_rphy(dev);
        struct sas_end_device *edev = rphy_to_end_device(rphy);

        put_device(dev->parent);
        kfree(edev);
}

/**
 * sas_end_device_alloc - allocate an rphy for an end device
 *
 * Allocates an SAS remote PHY structure, connected to @parent.
 *
 * Returns:
 *      SAS PHY allocated or %NULL if the allocation failed.
 */
struct sas_rphy *sas_end_device_alloc(struct sas_phy *parent)
{
        struct Scsi_Host *shost = dev_to_shost(&parent->dev);
        struct sas_end_device *rdev;

        rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
        if (!rdev) {
                return NULL;
        }

        device_initialize(&rdev->rphy.dev);
        rdev->rphy.dev.parent = get_device(&parent->dev);
        rdev->rphy.dev.release = sas_end_device_release;
        sprintf(rdev->rphy.dev.bus_id, "end_device-%d:%d-%d",
                shost->host_no, parent->port_identifier, parent->number);
        rdev->rphy.identify.device_type = SAS_END_DEVICE;
        transport_setup_device(&rdev->rphy.dev);

        return &rdev->rphy;
}
EXPORT_SYMBOL(sas_end_device_alloc);

/**
 * sas_expander_alloc - allocate an rphy for an end device
 *
 * Allocates an SAS remote PHY structure, connected to @parent.
 *
 * Returns:
 *      SAS PHY allocated or %NULL if the allocation failed.
 */
struct sas_rphy *sas_expander_alloc(struct sas_phy *parent,
                                    enum sas_device_type type)
{
        struct Scsi_Host *shost = dev_to_shost(&parent->dev);
        struct sas_expander_device *rdev;
        struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);

        BUG_ON(type != SAS_EDGE_EXPANDER_DEVICE &&
               type != SAS_FANOUT_EXPANDER_DEVICE);

        rdev = kzalloc(sizeof(*rdev), GFP_KERNEL);
        if (!rdev) {
                return NULL;
        }

        device_initialize(&rdev->rphy.dev);
        rdev->rphy.dev.parent = get_device(&parent->dev);
        rdev->rphy.dev.release = sas_expander_release;
        mutex_lock(&sas_host->lock);
        rdev->rphy.scsi_target_id = sas_host->next_expander_id++;
        mutex_unlock(&sas_host->lock);
        sprintf(rdev->rphy.dev.bus_id, "expander-%d:%d",
                shost->host_no, rdev->rphy.scsi_target_id);
        rdev->rphy.identify.device_type = type;
        transport_setup_device(&rdev->rphy.dev);

        return &rdev->rphy;
}
EXPORT_SYMBOL(sas_expander_alloc);

/**
 * sas_rphy_add  --  add a SAS remote PHY to the device hierachy
 * @rphy:       The remote PHY to be added
 *
 * Publishes a SAS remote PHY to the rest of the system.
 */
int sas_rphy_add(struct sas_rphy *rphy)
{
        struct sas_phy *parent = dev_to_phy(rphy->dev.parent);
        struct Scsi_Host *shost = dev_to_shost(parent->dev.parent);
        struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);
        struct sas_identify *identify = &rphy->identify;
        int error;

        if (parent->rphy)
                return -ENXIO;
        parent->rphy = rphy;

        error = device_add(&rphy->dev);
        if (error)
                return error;
        transport_add_device(&rphy->dev);
        transport_configure_device(&rphy->dev);

        mutex_lock(&sas_host->lock);
        list_add_tail(&rphy->list, &sas_host->rphy_list);
        if (identify->device_type == SAS_END_DEVICE &&
            (identify->target_port_protocols &
             (SAS_PROTOCOL_SSP|SAS_PROTOCOL_STP|SAS_PROTOCOL_SATA)))
                rphy->scsi_target_id = sas_host->next_target_id++;
        else if (identify->device_type == SAS_END_DEVICE)
                rphy->scsi_target_id = -1;
        mutex_unlock(&sas_host->lock);

        if (identify->device_type == SAS_END_DEVICE &&
            rphy->scsi_target_id != -1) {
                scsi_scan_target(&rphy->dev, parent->port_identifier,
                                rphy->scsi_target_id, ~0, 0);
        }

        return 0;
}
EXPORT_SYMBOL(sas_rphy_add);

/**
 * sas_rphy_free  --  free a SAS remote PHY
 * @rphy        SAS remote PHY to free
 *
 * Frees the specified SAS remote PHY.
 *
 * Note:
 *   This function must only be called on a remote
 *   PHY that has not sucessfully been added using
 *   sas_rphy_add().
 */
void sas_rphy_free(struct sas_rphy *rphy)
{
        struct device *dev = &rphy->dev;
        struct Scsi_Host *shost = dev_to_shost(rphy->dev.parent->parent);
        struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);

        mutex_lock(&sas_host->lock);
        list_del(&rphy->list);
        mutex_unlock(&sas_host->lock);

        transport_destroy_device(dev);

        put_device(dev);
}
EXPORT_SYMBOL(sas_rphy_free);

/**
 * sas_rphy_delete  --  remove SAS remote PHY
 * @rphy:       SAS remote PHY to remove
 *
 * Removes the specified SAS remote PHY.
 */
void
sas_rphy_delete(struct sas_rphy *rphy)
{
        struct device *dev = &rphy->dev;
        struct sas_phy *parent = dev_to_phy(dev->parent);
        struct Scsi_Host *shost = dev_to_shost(parent->dev.parent);
        struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);

        switch (rphy->identify.device_type) {
        case SAS_END_DEVICE:
                scsi_remove_target(dev);
                break;
        case SAS_EDGE_EXPANDER_DEVICE:
        case SAS_FANOUT_EXPANDER_DEVICE:
                device_for_each_child(dev, NULL, do_sas_phy_delete);
                break;
        default:
                break;
        }

        transport_remove_device(dev);
        device_del(dev);
        transport_destroy_device(dev);

        mutex_lock(&sas_host->lock);
        list_del(&rphy->list);
        mutex_unlock(&sas_host->lock);

        parent->rphy = NULL;

        put_device(dev);
}
EXPORT_SYMBOL(sas_rphy_delete);

/**
 * scsi_is_sas_rphy  --  check if a struct device represents a SAS remote PHY
 * @dev:        device to check
 *
 * Returns:
 *      %1 if the device represents a SAS remote PHY, %0 else
 */
int scsi_is_sas_rphy(const struct device *dev)
{
        return dev->release == sas_end_device_release ||
                dev->release == sas_expander_release;
}
EXPORT_SYMBOL(scsi_is_sas_rphy);


/*
 * SCSI scan helper
 */

static int sas_user_scan(struct Scsi_Host *shost, uint channel,
                uint id, uint lun)
{
        struct sas_host_attrs *sas_host = to_sas_host_attrs(shost);
        struct sas_rphy *rphy;

        mutex_lock(&sas_host->lock);
        list_for_each_entry(rphy, &sas_host->rphy_list, list) {
                struct sas_phy *parent = dev_to_phy(rphy->dev.parent);

                if (rphy->scsi_target_id == -1)
                        continue;

                if ((channel == SCAN_WILD_CARD || channel == parent->port_identifier) &&
                    (id == SCAN_WILD_CARD || id == rphy->scsi_target_id)) {
                        scsi_scan_target(&rphy->dev, parent->port_identifier,
                                         rphy->scsi_target_id, lun, 1);
                }
        }
        mutex_unlock(&sas_host->lock);

        return 0;
}


/*
 * Setup / Teardown code
 */

#define SETUP_TEMPLATE(attrb, field, perm, test)                                \
        i->private_##attrb[count] = class_device_attr_##field;          \
        i->private_##attrb[count].attr.mode = perm;                     \
        i->private_##attrb[count].store = NULL;                         \
        i->attrb[count] = &i->private_##attrb[count];                   \
        if (test)                                                       \
                count++


#define SETUP_RPORT_ATTRIBUTE(field)                                    \
        SETUP_TEMPLATE(rphy_attrs, field, S_IRUGO, 1)

#define SETUP_OPTIONAL_RPORT_ATTRIBUTE(field, func)                     \
        SETUP_TEMPLATE(rphy_attrs, field, S_IRUGO, i->f->func)

#define SETUP_PORT_ATTRIBUTE(field)                                     \
        SETUP_TEMPLATE(phy_attrs, field, S_IRUGO, 1)

#define SETUP_OPTIONAL_PORT_ATTRIBUTE(field, func)                      \
        SETUP_TEMPLATE(phy_attrs, field, S_IRUGO, i->f->func)

#define SETUP_PORT_ATTRIBUTE_WRONLY(field)                              \
        SETUP_TEMPLATE(phy_attrs, field, S_IWUGO, 1)

#define SETUP_OPTIONAL_PORT_ATTRIBUTE_WRONLY(field, func)               \
        SETUP_TEMPLATE(phy_attrs, field, S_IWUGO, i->f->func)

#define SETUP_END_DEV_ATTRIBUTE(field)                                  \
        SETUP_TEMPLATE(end_dev_attrs, field, S_IRUGO, 1)

#define SETUP_EXPANDER_ATTRIBUTE(field)                                 \
        SETUP_TEMPLATE(expander_attrs, expander_##field, S_IRUGO, 1)

/**
 * sas_attach_transport  --  instantiate SAS transport template
 * @ft:         SAS transport class function template
 */
struct scsi_transport_template *
sas_attach_transport(struct sas_function_template *ft)
{
        struct sas_internal *i;
        int count;

        i = kzalloc(sizeof(struct sas_internal), GFP_KERNEL);
        if (!i)
                return NULL;

        i->t.user_scan = sas_user_scan;

        i->t.host_attrs.ac.attrs = &i->host_attrs[0];
        i->t.host_attrs.ac.class = &sas_host_class.class;
        i->t.host_attrs.ac.match = sas_host_match;
        transport_container_register(&i->t.host_attrs);
        i->t.host_size = sizeof(struct sas_host_attrs);

        i->phy_attr_cont.ac.class = &sas_phy_class.class;
        i->phy_attr_cont.ac.attrs = &i->phy_attrs[0];
        i->phy_attr_cont.ac.match = sas_phy_match;
        transport_container_register(&i->phy_attr_cont);

        i->rphy_attr_cont.ac.class = &sas_rphy_class.class;
        i->rphy_attr_cont.ac.attrs = &i->rphy_attrs[0];
        i->rphy_attr_cont.ac.match = sas_rphy_match;
        transport_container_register(&i->rphy_attr_cont);

        i->end_dev_attr_cont.ac.class = &sas_end_dev_class.class;
        i->end_dev_attr_cont.ac.attrs = &i->end_dev_attrs[0];
        i->end_dev_attr_cont.ac.match = sas_end_dev_match;
        transport_container_register(&i->end_dev_attr_cont);

        i->expander_attr_cont.ac.class = &sas_expander_class.class;
        i->expander_attr_cont.ac.attrs = &i->expander_attrs[0];
        i->expander_attr_cont.ac.match = sas_expander_match;
        transport_container_register(&i->expander_attr_cont);

        i->f = ft;

        count = 0;
        i->host_attrs[count] = NULL;

        count = 0;
        SETUP_PORT_ATTRIBUTE(initiator_port_protocols);
        SETUP_PORT_ATTRIBUTE(target_port_protocols);
        SETUP_PORT_ATTRIBUTE(device_type);
        SETUP_PORT_ATTRIBUTE(sas_address);
        SETUP_PORT_ATTRIBUTE(phy_identifier);
        SETUP_PORT_ATTRIBUTE(port_identifier);
        SETUP_PORT_ATTRIBUTE(negotiated_linkrate);
        SETUP_PORT_ATTRIBUTE(minimum_linkrate_hw);
        SETUP_PORT_ATTRIBUTE(minimum_linkrate);
        SETUP_PORT_ATTRIBUTE(maximum_linkrate_hw);
        SETUP_PORT_ATTRIBUTE(maximum_linkrate);

        SETUP_PORT_ATTRIBUTE(invalid_dword_count);
        SETUP_PORT_ATTRIBUTE(running_disparity_error_count);
        SETUP_PORT_ATTRIBUTE(loss_of_dword_sync_count);
        SETUP_PORT_ATTRIBUTE(phy_reset_problem_count);
        SETUP_OPTIONAL_PORT_ATTRIBUTE_WRONLY(link_reset, phy_reset);
        SETUP_OPTIONAL_PORT_ATTRIBUTE_WRONLY(hard_reset, phy_reset);
        i->phy_attrs[count] = NULL;

        count = 0;
        SETUP_RPORT_ATTRIBUTE(rphy_initiator_port_protocols);
        SETUP_RPORT_ATTRIBUTE(rphy_target_port_protocols);
        SETUP_RPORT_ATTRIBUTE(rphy_device_type);
        SETUP_RPORT_ATTRIBUTE(rphy_sas_address);
        SETUP_RPORT_ATTRIBUTE(rphy_phy_identifier);
        SETUP_OPTIONAL_RPORT_ATTRIBUTE(rphy_enclosure_identifier,
                                       get_enclosure_identifier);
        SETUP_OPTIONAL_RPORT_ATTRIBUTE(rphy_bay_identifier,
                                       get_bay_identifier);
        i->rphy_attrs[count] = NULL;

        count = 0;
        SETUP_END_DEV_ATTRIBUTE(end_dev_ready_led_meaning);
        SETUP_END_DEV_ATTRIBUTE(end_dev_I_T_nexus_loss_timeout);
        SETUP_END_DEV_ATTRIBUTE(end_dev_initiator_response_timeout);
        i->end_dev_attrs[count] = NULL;

        count = 0;
        SETUP_EXPANDER_ATTRIBUTE(vendor_id);
        SETUP_EXPANDER_ATTRIBUTE(product_id);
        SETUP_EXPANDER_ATTRIBUTE(product_rev);
        SETUP_EXPANDER_ATTRIBUTE(component_vendor_id);
        SETUP_EXPANDER_ATTRIBUTE(component_id);
        SETUP_EXPANDER_ATTRIBUTE(component_revision_id);
        SETUP_EXPANDER_ATTRIBUTE(level);
        i->expander_attrs[count] = NULL;

        return &i->t;
}
EXPORT_SYMBOL(sas_attach_transport);

/**
 * sas_release_transport  --  release SAS transport template instance
 * @t:          transport template instance
 */
void sas_release_transport(struct scsi_transport_template *t)
{
        struct sas_internal *i = to_sas_internal(t);

        transport_container_unregister(&i->t.host_attrs);
        transport_container_unregister(&i->phy_attr_cont);
        transport_container_unregister(&i->rphy_attr_cont);
        transport_container_unregister(&i->end_dev_attr_cont);
        transport_container_unregister(&i->expander_attr_cont);

        kfree(i);
}
EXPORT_SYMBOL(sas_release_transport);

static __init int sas_transport_init(void)
{
        int error;

        error = transport_class_register(&sas_host_class);
        if (error)
                goto out;
        error = transport_class_register(&sas_phy_class);
        if (error)
                goto out_unregister_transport;
        error = transport_class_register(&sas_rphy_class);
        if (error)
                goto out_unregister_phy;
        error = transport_class_register(&sas_end_dev_class);
        if (error)
                goto out_unregister_rphy;
        error = transport_class_register(&sas_expander_class);
        if (error)
                goto out_unregister_end_dev;

        return 0;

 out_unregister_end_dev:
        transport_class_unregister(&sas_end_dev_class);
 out_unregister_rphy:
        transport_class_unregister(&sas_rphy_class);
 out_unregister_phy:
        transport_class_unregister(&sas_phy_class);
 out_unregister_transport:
        transport_class_unregister(&sas_host_class);
 out:
        return error;

}

static void __exit sas_transport_exit(void)
{
        transport_class_unregister(&sas_host_class);
        transport_class_unregister(&sas_phy_class);
        transport_class_unregister(&sas_rphy_class);
        transport_class_unregister(&sas_end_dev_class);
        transport_class_unregister(&sas_expander_class);
}

MODULE_AUTHOR("Christoph Hellwig");
MODULE_DESCRIPTION("SAS Transphy Attributes");
MODULE_LICENSE("GPL");

module_init(sas_transport_init);
module_exit(sas_transport_exit);