Linux-2.6.12-rc2v2.6.12-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 000000000000..27f2c4e8943a
--- /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+         * Status:  OBSOLETE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+         * Status: OBSOLETE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 */