Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 642 insertions, 0 deletions

diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
new file mode 100644
index 00000000000..27f2c4e8943
--- /dev/null
+++ b/include/scsi/scsi_host.h
@@ -0,0 +1,642 @@
+#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+	 * Status:  OBSOLETE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+	 * Status: OBSOLETE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 */