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diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
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+#ifndef _SCSI_SCSI_HOST_H
+#define _SCSI_SCSI_HOST_H
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/types.h>
+#include <linux/workqueue.h>
+
+struct block_device;
+struct module;
+struct scsi_cmnd;
+struct scsi_device;
+struct Scsi_Host;
+struct scsi_host_cmd_pool;
+struct scsi_transport_template;
+
+
+/*
+ * The various choices mean:
+ * NONE: Self evident. Host adapter is not capable of scatter-gather.
+ * ALL: Means that the host adapter module can do scatter-gather,
+ * and that there is no limit to the size of the table to which
+ * we scatter/gather data.
+ * Anything else: Indicates the maximum number of chains that can be
+ * used in one scatter-gather request.
+ */
+#define SG_NONE 0
+#define SG_ALL 0xff
+
+
+#define DISABLE_CLUSTERING 0
+#define ENABLE_CLUSTERING 1
+
+enum scsi_eh_timer_return {
+ EH_NOT_HANDLED,
+ EH_HANDLED,
+ EH_RESET_TIMER,
+};
+
+
+struct scsi_host_template {
+ struct module *module;
+ const char *name;
+
+ /*
+ * Used to initialize old-style drivers. For new-style drivers
+ * just perform all work in your module initialization function.
+ *
+ * Status: OBSOLETE
+ */
+ int (* detect)(struct scsi_host_template *);
+
+ /*
+ * Used as unload callback for hosts with old-style drivers.
+ *
+ * Status: OBSOLETE
+ */
+ int (* release)(struct Scsi_Host *);
+
+ /*
+ * The info function will return whatever useful information the
+ * developer sees fit. If not provided, then the name field will
+ * be used instead.
+ *
+ * Status: OPTIONAL
+ */
+ const char *(* info)(struct Scsi_Host *);
+
+ /*
+ * Ioctl interface
+ *
+ * Status: OPTIONAL
+ */
+ int (* ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
+
+
+#ifdef CONFIG_COMPAT
+ /*
+ * Compat handler. Handle 32bit ABI.
+ * When unknown ioctl is passed return -ENOIOCTLCMD.
+ *
+ * Status: OPTIONAL
+ */
+ int (* compat_ioctl)(struct scsi_device *dev, int cmd, void __user *arg);
+#endif
+
+ /*
+ * The queuecommand function is used to queue up a scsi
+ * command block to the LLDD. When the driver finished
+ * processing the command the done callback is invoked.
+ *
+ * If queuecommand returns 0, then the HBA has accepted the
+ * command. The done() function must be called on the command
+ * when the driver has finished with it. (you may call done on the
+ * command before queuecommand returns, but in this case you
+ * *must* return 0 from queuecommand).
+ *
+ * Queuecommand may also reject the command, in which case it may
+ * not touch the command and must not call done() for it.
+ *
+ * There are two possible rejection returns:
+ *
+ * SCSI_MLQUEUE_DEVICE_BUSY: Block this device temporarily, but
+ * allow commands to other devices serviced by this host.
+ *
+ * SCSI_MLQUEUE_HOST_BUSY: Block all devices served by this
+ * host temporarily.
+ *
+ * For compatibility, any other non-zero return is treated the
+ * same as SCSI_MLQUEUE_HOST_BUSY.
+ *
+ * NOTE: "temporarily" means either until the next command for#
+ * this device/host completes, or a period of time determined by
+ * I/O pressure in the system if there are no other outstanding
+ * commands.
+ *
+ * STATUS: REQUIRED
+ */
+ int (* queuecommand)(struct scsi_cmnd *,
+ void (*done)(struct scsi_cmnd *));
+
+ /*
+ * This is an error handling strategy routine. You don't need to
+ * define one of these if you don't want to - there is a default
+ * routine that is present that should work in most cases. For those
+ * driver authors that have the inclination and ability to write their
+ * own strategy routine, this is where it is specified. Note - the
+ * strategy routine is *ALWAYS* run in the context of the kernel eh
+ * thread. Thus you are guaranteed to *NOT* be in an interrupt
+ * handler when you execute this, and you are also guaranteed to
+ * *NOT* have any other commands being queued while you are in the
+ * strategy routine. When you return from this function, operations
+ * return to normal.
+ *
+ * See scsi_error.c scsi_unjam_host for additional comments about
+ * what this function should and should not be attempting to do.
+ *
+ * Status: REQUIRED (at least one of them)
+ */
+ int (* eh_strategy_handler)(struct Scsi_Host *);
+ int (* eh_abort_handler)(struct scsi_cmnd *);
+ int (* eh_device_reset_handler)(struct scsi_cmnd *);
+ int (* eh_bus_reset_handler)(struct scsi_cmnd *);
+ int (* eh_host_reset_handler)(struct scsi_cmnd *);
+
+ /*
+ * This is an optional routine to notify the host that the scsi
+ * timer just fired. The returns tell the timer routine what to
+ * do about this:
+ *
+ * EH_HANDLED: I fixed the error, please complete the command
+ * EH_RESET_TIMER: I need more time, reset the timer and
+ * begin counting again
+ * EH_NOT_HANDLED Begin normal error recovery
+ *
+ * Status: OPTIONAL
+ */
+ enum scsi_eh_timer_return (* eh_timed_out)(struct scsi_cmnd *);
+
+ /*
+ * Before the mid layer attempts to scan for a new device where none
+ * currently exists, it will call this entry in your driver. Should
+ * your driver need to allocate any structs or perform any other init
+ * items in order to send commands to a currently unused target/lun
+ * combo, then this is where you can perform those allocations. This
+ * is specifically so that drivers won't have to perform any kind of
+ * "is this a new device" checks in their queuecommand routine,
+ * thereby making the hot path a bit quicker.
+ *
+ * Return values: 0 on success, non-0 on failure
+ *
+ * Deallocation: If we didn't find any devices at this ID, you will
+ * get an immediate call to slave_destroy(). If we find something
+ * here then you will get a call to slave_configure(), then the
+ * device will be used for however long it is kept around, then when
+ * the device is removed from the system (or * possibly at reboot
+ * time), you will then get a call to slave_destroy(). This is
+ * assuming you implement slave_configure and slave_destroy.
+ * However, if you allocate memory and hang it off the device struct,
+ * then you must implement the slave_destroy() routine at a minimum
+ * in order to avoid leaking memory
+ * each time a device is tore down.
+ *
+ * Status: OPTIONAL
+ */
+ int (* slave_alloc)(struct scsi_device *);
+
+ /*
+ * Once the device has responded to an INQUIRY and we know the
+ * device is online, we call into the low level driver with the
+ * struct scsi_device *. If the low level device driver implements
+ * this function, it *must* perform the task of setting the queue
+ * depth on the device. All other tasks are optional and depend
+ * on what the driver supports and various implementation details.
+ *
+ * Things currently recommended to be handled at this time include:
+ *
+ * 1. Setting the device queue depth. Proper setting of this is
+ * described in the comments for scsi_adjust_queue_depth.
+ * 2. Determining if the device supports the various synchronous
+ * negotiation protocols. The device struct will already have
+ * responded to INQUIRY and the results of the standard items
+ * will have been shoved into the various device flag bits, eg.
+ * device->sdtr will be true if the device supports SDTR messages.
+ * 3. Allocating command structs that the device will need.
+ * 4. Setting the default timeout on this device (if needed).
+ * 5. Anything else the low level driver might want to do on a device
+ * specific setup basis...
+ * 6. Return 0 on success, non-0 on error. The device will be marked
+ * as offline on error so that no access will occur. If you return
+ * non-0, your slave_destroy routine will never get called for this
+ * device, so don't leave any loose memory hanging around, clean
+ * up after yourself before returning non-0
+ *
+ * Status: OPTIONAL
+ */
+ int (* slave_configure)(struct scsi_device *);
+
+ /*
+ * Immediately prior to deallocating the device and after all activity
+ * has ceased the mid layer calls this point so that the low level
+ * driver may completely detach itself from the scsi device and vice
+ * versa. The low level driver is responsible for freeing any memory
+ * it allocated in the slave_alloc or slave_configure calls.
+ *
+ * Status: OPTIONAL
+ */
+ void (* slave_destroy)(struct scsi_device *);
+
+ /*
+ * fill in this function to allow the queue depth of this host
+ * to be changeable (on a per device basis). returns either
+ * the current queue depth setting (may be different from what
+ * was passed in) or an error. An error should only be
+ * returned if the requested depth is legal but the driver was
+ * unable to set it. If the requested depth is illegal, the
+ * driver should set and return the closest legal queue depth.
+ *
+ */
+ int (* change_queue_depth)(struct scsi_device *, int);
+
+ /*
+ * fill in this function to allow the changing of tag types
+ * (this also allows the enabling/disabling of tag command
+ * queueing). An error should only be returned if something
+ * went wrong in the driver while trying to set the tag type.
+ * If the driver doesn't support the requested tag type, then
+ * it should set the closest type it does support without
+ * returning an error. Returns the actual tag type set.
+ */
+ int (* change_queue_type)(struct scsi_device *, int);
+
+ /*
+ * This function determines the bios parameters for a given
+ * harddisk. These tend to be numbers that are made up by
+ * the host adapter. Parameters:
+ * size, device, list (heads, sectors, cylinders)
+ *
+ * Status: OPTIONAL */
+ int (* bios_param)(struct scsi_device *, struct block_device *,
+ sector_t, int []);
+
+ /*
+ * Can be used to export driver statistics and other infos to the
+ * world outside the kernel ie. userspace and it also provides an
+ * interface to feed the driver with information.
+ *
+ * Status: OBSOLETE
+ */
+ int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int);
+
+ /*
+ * Name of proc directory
+ */
+ char *proc_name;
+
+ /*
+ * Used to store the procfs directory if a driver implements the
+ * proc_info method.
+ */
+ struct proc_dir_entry *proc_dir;
+
+ /*
+ * This determines if we will use a non-interrupt driven
+ * or an interrupt driven scheme, It is set to the maximum number
+ * of simultaneous commands a given host adapter will accept.
+ */
+ int can_queue;
+
+ /*
+ * In many instances, especially where disconnect / reconnect are
+ * supported, our host also has an ID on the SCSI bus. If this is
+ * the case, then it must be reserved. Please set this_id to -1 if
+ * your setup is in single initiator mode, and the host lacks an
+ * ID.
+ */
+ int this_id;
+
+ /*
+ * This determines the degree to which the host adapter is capable
+ * of scatter-gather.
+ */
+ unsigned short sg_tablesize;
+
+ /*
+ * If the host adapter has limitations beside segment count
+ */
+ unsigned short max_sectors;
+
+ /*
+ * dma scatter gather segment boundary limit. a segment crossing this
+ * boundary will be split in two.
+ */
+ unsigned long dma_boundary;
+
+ /*
+ * This specifies "machine infinity" for host templates which don't
+ * limit the transfer size. Note this limit represents an absolute
+ * maximum, and may be over the transfer limits allowed for
+ * individual devices (e.g. 256 for SCSI-1)
+ */
+#define SCSI_DEFAULT_MAX_SECTORS 1024
+
+ /*
+ * True if this host adapter can make good use of linked commands.
+ * This will allow more than one command to be queued to a given
+ * unit on a given host. Set this to the maximum number of command
+ * blocks to be provided for each device. Set this to 1 for one
+ * command block per lun, 2 for two, etc. Do not set this to 0.
+ * You should make sure that the host adapter will do the right thing
+ * before you try setting this above 1.
+ */
+ short cmd_per_lun;
+
+ /*
+ * present contains counter indicating how many boards of this
+ * type were found when we did the scan.
+ */
+ unsigned char present;
+
+ /*
+ * true if this host adapter uses unchecked DMA onto an ISA bus.
+ */
+ unsigned unchecked_isa_dma:1;
+
+ /*
+ * true if this host adapter can make good use of clustering.
+ * I originally thought that if the tablesize was large that it
+ * was a waste of CPU cycles to prepare a cluster list, but
+ * it works out that the Buslogic is faster if you use a smaller
+ * number of segments (i.e. use clustering). I guess it is
+ * inefficient.
+ */
+ unsigned use_clustering:1;
+
+ /*
+ * True for emulated SCSI host adapters (e.g. ATAPI)
+ */
+ unsigned emulated:1;
+
+ /*
+ * True if the low-level driver performs its own reset-settle delays.
+ */
+ unsigned skip_settle_delay:1;
+
+ /*
+ * ordered write support
+ */
+ unsigned ordered_flush:1;
+ unsigned ordered_tag:1;
+
+ /*
+ * Countdown for host blocking with no commands outstanding
+ */
+ unsigned int max_host_blocked;
+
+ /*
+ * Default value for the blocking. If the queue is empty,
+ * host_blocked counts down in the request_fn until it restarts
+ * host operations as zero is reached.
+ *
+ * FIXME: This should probably be a value in the template
+ */
+#define SCSI_DEFAULT_HOST_BLOCKED 7
+
+ /*
+ * Pointer to the sysfs class properties for this host, NULL terminated.
+ */
+ struct class_device_attribute **shost_attrs;
+
+ /*
+ * Pointer to the SCSI device properties for this host, NULL terminated.
+ */
+ struct device_attribute **sdev_attrs;
+
+ /*
+ * List of hosts per template.
+ *
+ * This is only for use by scsi_module.c for legacy templates.
+ * For these access to it is synchronized implicitly by
+ * module_init/module_exit.
+ */
+ struct list_head legacy_hosts;
+};
+
+/*
+ * shost states
+ */
+enum {
+ SHOST_ADD,
+ SHOST_DEL,
+ SHOST_CANCEL,
+ SHOST_RECOVERY,
+};
+
+struct Scsi_Host {
+ /*
+ * __devices is protected by the host_lock, but you should
+ * usually use scsi_device_lookup / shost_for_each_device
+ * to access it and don't care about locking yourself.
+ * In the rare case of beeing in irq context you can use
+ * their __ prefixed variants with the lock held. NEVER
+ * access this list directly from a driver.
+ */
+ struct list_head __devices;
+ struct list_head __targets;
+
+ struct scsi_host_cmd_pool *cmd_pool;
+ spinlock_t free_list_lock;
+ struct list_head free_list; /* backup store of cmd structs */
+ struct list_head starved_list;
+
+ spinlock_t default_lock;
+ spinlock_t *host_lock;
+
+ struct semaphore scan_mutex;/* serialize scanning activity */
+
+ struct list_head eh_cmd_q;
+ struct task_struct * ehandler; /* Error recovery thread. */
+ struct semaphore * eh_wait; /* The error recovery thread waits
+ on this. */
+ struct completion * eh_notify; /* wait for eh to begin or end */
+ struct semaphore * eh_action; /* Wait for specific actions on the
+ host. */
+ unsigned int eh_active:1; /* Indicates the eh thread is awake and active if
+ this is true. */
+ unsigned int eh_kill:1; /* set when killing the eh thread */
+ wait_queue_head_t host_wait;
+ struct scsi_host_template *hostt;
+ struct scsi_transport_template *transportt;
+ volatile unsigned short host_busy; /* commands actually active on low-level */
+ volatile unsigned short host_failed; /* commands that failed. */
+
+ unsigned short host_no; /* Used for IOCTL_GET_IDLUN, /proc/scsi et al. */
+ int resetting; /* if set, it means that last_reset is a valid value */
+ unsigned long last_reset;
+
+ /*
+ * These three parameters can be used to allow for wide scsi,
+ * and for host adapters that support multiple busses
+ * The first two should be set to 1 more than the actual max id
+ * or lun (i.e. 8 for normal systems).
+ */
+ unsigned int max_id;
+ unsigned int max_lun;
+ unsigned int max_channel;
+
+ /*
+ * This is a unique identifier that must be assigned so that we
+ * have some way of identifying each detected host adapter properly
+ * and uniquely. For hosts that do not support more than one card
+ * in the system at one time, this does not need to be set. It is
+ * initialized to 0 in scsi_register.
+ */
+ unsigned int unique_id;
+
+ /*
+ * The maximum length of SCSI commands that this host can accept.
+ * Probably 12 for most host adapters, but could be 16 for others.
+ * For drivers that don't set this field, a value of 12 is
+ * assumed. I am leaving this as a number rather than a bit
+ * because you never know what subsequent SCSI standards might do
+ * (i.e. could there be a 20 byte or a 24-byte command a few years
+ * down the road?).
+ */
+ unsigned char max_cmd_len;
+
+ int this_id;
+ int can_queue;
+ short cmd_per_lun;
+ short unsigned int sg_tablesize;
+ short unsigned int max_sectors;
+ unsigned long dma_boundary;
+ /*
+ * Used to assign serial numbers to the cmds.
+ * Protected by the host lock.
+ */
+ unsigned long cmd_serial_number, cmd_pid;
+
+ unsigned unchecked_isa_dma:1;
+ unsigned use_clustering:1;
+ unsigned use_blk_tcq:1;
+
+ /*
+ * Host has requested that no further requests come through for the
+ * time being.
+ */
+ unsigned host_self_blocked:1;
+
+ /*
+ * Host uses correct SCSI ordering not PC ordering. The bit is
+ * set for the minority of drivers whose authors actually read
+ * the spec ;)
+ */
+ unsigned reverse_ordering:1;
+
+ /*
+ * ordered write support
+ */
+ unsigned ordered_flush:1;
+ unsigned ordered_tag:1;
+
+ /*
+ * Optional work queue to be utilized by the transport
+ */
+ char work_q_name[KOBJ_NAME_LEN];
+ struct workqueue_struct *work_q;
+
+ /*
+ * Host has rejected a command because it was busy.
+ */
+ unsigned int host_blocked;
+
+ /*
+ * Value host_blocked counts down from
+ */
+ unsigned int max_host_blocked;
+
+ /* legacy crap */
+ unsigned long base;
+ unsigned long io_port;
+ unsigned char n_io_port;
+ unsigned char dma_channel;
+ unsigned int irq;
+
+
+ unsigned long shost_state;
+
+ /* ldm bits */
+ struct device shost_gendev;
+ struct class_device shost_classdev;
+
+ /*
+ * List of hosts per template.
+ *
+ * This is only for use by scsi_module.c for legacy templates.
+ * For these access to it is synchronized implicitly by
+ * module_init/module_exit.
+ */
+ struct list_head sht_legacy_list;
+
+ /*
+ * Points to the transport data (if any) which is allocated
+ * separately
+ */
+ void *shost_data;
+
+ /*
+ * We should ensure that this is aligned, both for better performance
+ * and also because some compilers (m68k) don't automatically force
+ * alignment to a long boundary.
+ */
+ unsigned long hostdata[0] /* Used for storage of host specific stuff */
+ __attribute__ ((aligned (sizeof(unsigned long))));
+};
+
+#define class_to_shost(d) \
+ container_of(d, struct Scsi_Host, shost_classdev)
+
+int scsi_is_host_device(const struct device *);
+
+static inline struct Scsi_Host *dev_to_shost(struct device *dev)
+{
+ while (!scsi_is_host_device(dev)) {
+ if (!dev->parent)
+ return NULL;
+ dev = dev->parent;
+ }
+ return container_of(dev, struct Scsi_Host, shost_gendev);
+}
+
+extern int scsi_queue_work(struct Scsi_Host *, struct work_struct *);
+extern void scsi_flush_work(struct Scsi_Host *);
+
+extern struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *, int);
+extern int __must_check scsi_add_host(struct Scsi_Host *, struct device *);
+extern void scsi_scan_host(struct Scsi_Host *);
+extern void scsi_scan_single_target(struct Scsi_Host *, unsigned int,
+ unsigned int);
+extern void scsi_rescan_device(struct device *);
+extern void scsi_remove_host(struct Scsi_Host *);
+extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);
+extern void scsi_host_put(struct Scsi_Host *t);
+extern struct Scsi_Host *scsi_host_lookup(unsigned short);
+
+extern u64 scsi_calculate_bounce_limit(struct Scsi_Host *);
+
+static inline void scsi_assign_lock(struct Scsi_Host *shost, spinlock_t *lock)
+{
+ shost->host_lock = lock;
+}
+
+static inline void scsi_set_device(struct Scsi_Host *shost,
+ struct device *dev)
+{
+ shost->shost_gendev.parent = dev;
+}
+
+static inline struct device *scsi_get_device(struct Scsi_Host *shost)
+{
+ return shost->shost_gendev.parent;
+}
+
+extern void scsi_unblock_requests(struct Scsi_Host *);
+extern void scsi_block_requests(struct Scsi_Host *);
+
+struct class_container;
+/*
+ * These two functions are used to allocate and free a pseudo device
+ * which will connect to the host adapter itself rather than any
+ * physical device. You must deallocate when you are done with the
+ * thing. This physical pseudo-device isn't real and won't be available
+ * from any high-level drivers.
+ */
+extern void scsi_free_host_dev(struct scsi_device *);
+extern struct scsi_device *scsi_get_host_dev(struct Scsi_Host *);
+
+/* legacy interfaces */
+extern struct Scsi_Host *scsi_register(struct scsi_host_template *, int);
+extern void scsi_unregister(struct Scsi_Host *);
+
+#endif /* _SCSI_SCSI_HOST_H */