| /* |
| * hosts.h Copyright (C) 1992 Drew Eckhardt |
| * Copyright (C) 1993, 1994, 1995, 1998, 1999 Eric Youngdale |
| * |
| * mid to low-level SCSI driver interface header |
| * Initial versions: Drew Eckhardt |
| * Subsequent revisions: Eric Youngdale |
| * |
| * <drew@colorado.edu> |
| * |
| * Modified by Eric Youngdale eric@andante.org to |
| * add scatter-gather, multiple outstanding request, and other |
| * enhancements. |
| * |
| * Further modified by Eric Youngdale to support multiple host adapters |
| * of the same type. |
| * |
| * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli |
| */ |
| |
| #ifndef _HOSTS_H |
| #define _HOSTS_H |
| |
| /* |
| $Header: /vger/u4/cvs/linux/drivers/scsi/hosts.h,v 1.6 1997/01/19 23:07:13 davem Exp $ |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/proc_fs.h> |
| #include <linux/pci.h> |
| |
| /* It is senseless to set SG_ALL any higher than this - the performance |
| * does not get any better, and it wastes memory |
| */ |
| #define SG_NONE 0 |
| #define SG_ALL 0xff |
| |
| #define DISABLE_CLUSTERING 0 |
| #define ENABLE_CLUSTERING 1 |
| |
| /* 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. |
| */ |
| |
| /* |
| * The Scsi_Host_Template type has all that is needed to interface with a SCSI |
| * host in a device independent matter. There is one entry for each different |
| * type of host adapter that is supported on the system. |
| */ |
| |
| typedef struct scsi_disk Disk; |
| |
| typedef struct SHT |
| { |
| |
| /* Used with loadable modules so we can construct a linked list. */ |
| struct SHT * next; |
| |
| /* Used with loadable modules so that we know when it is safe to unload */ |
| struct module * module; |
| |
| /* The pointer to the /proc/scsi directory entry */ |
| struct proc_dir_entry *proc_dir; |
| |
| /* proc-fs info function. |
| * 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. Check eata_dma_proc.c for reference |
| */ |
| int (*proc_info)(char *, char **, off_t, int, int, int); |
| |
| /* |
| * The name pointer is a pointer to the name of the SCSI |
| * device detected. |
| */ |
| const char *name; |
| |
| /* |
| * The detect function shall return non zero on detection, |
| * indicating the number of host adapters of this particular |
| * type were found. It should also |
| * initialize all data necessary for this particular |
| * SCSI driver. It is passed the host number, so this host |
| * knows where the first entry is in the scsi_hosts[] array. |
| * |
| * Note that the detect routine MUST not call any of the mid level |
| * functions to queue commands because things are not guaranteed |
| * to be set up yet. The detect routine can send commands to |
| * the host adapter as long as the program control will not be |
| * passed to scsi.c in the processing of the command. Note |
| * especially that scsi_malloc/scsi_free must not be called. |
| */ |
| int (* detect)(struct SHT *); |
| |
| int (*revoke)(Scsi_Device *); |
| |
| /* Used with loadable modules to unload the host structures. Note: |
| * there is a default action built into the modules code which may |
| * be sufficient for most host adapters. Thus you may not have to supply |
| * this at all. |
| */ |
| 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. |
| */ |
| const char *(* info)(struct Scsi_Host *); |
| |
| /* |
| * ioctl interface |
| */ |
| int (*ioctl)(Scsi_Device *dev, int cmd, void *arg); |
| |
| /* |
| * The command function takes a target, a command (this is a SCSI |
| * command formatted as per the SCSI spec, nothing strange), a |
| * data buffer pointer, and data buffer length pointer. The return |
| * is a status int, bit fielded as follows : |
| * Byte What |
| * 0 SCSI status code |
| * 1 SCSI 1 byte message |
| * 2 host error return. |
| * 3 mid level error return |
| */ |
| int (* command)(Scsi_Cmnd *); |
| |
| /* |
| * The QueueCommand function works in a similar manner |
| * to the command function. It takes an additional parameter, |
| * void (* done)(int host, int code) which is passed the host |
| * # and exit result when the command is complete. |
| * Host number is the POSITION IN THE hosts array of THIS |
| * host adapter. |
| * |
| * The done() function must only be called after QueueCommand() |
| * has returned. |
| */ |
| int (* queuecommand)(Scsi_Cmnd *, void (*done)(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. |
| */ |
| int (*eh_strategy_handler)(struct Scsi_Host *); |
| int (*eh_abort_handler)(Scsi_Cmnd *); |
| int (*eh_device_reset_handler)(Scsi_Cmnd *); |
| int (*eh_bus_reset_handler)(Scsi_Cmnd *); |
| int (*eh_host_reset_handler)(Scsi_Cmnd *); |
| |
| /* |
| * Since the mid level driver handles time outs, etc, we want to |
| * be able to abort the current command. Abort returns 0 if the |
| * abortion was successful. The field SCpnt->abort reason |
| * can be filled in with the appropriate reason why we wanted |
| * the abort in the first place, and this will be used |
| * in the mid-level code instead of the host_byte(). |
| * If non-zero, the code passed to it |
| * will be used as the return code, otherwise |
| * DID_ABORT should be returned. |
| * |
| * Note that the scsi driver should "clean up" after itself, |
| * resetting the bus, etc. if necessary. |
| * |
| * NOTE - this interface is depreciated, and will go away. Use |
| * the eh_ routines instead. |
| */ |
| int (* abort)(Scsi_Cmnd *); |
| |
| /* |
| * The reset function will reset the SCSI bus. Any executing |
| * commands should fail with a DID_RESET in the host byte. |
| * The Scsi_Cmnd is passed so that the reset routine can figure |
| * out which host adapter should be reset, and also which command |
| * within the command block was responsible for the reset in |
| * the first place. Some hosts do not implement a reset function, |
| * and these hosts must call scsi_request_sense(SCpnt) to keep |
| * the command alive. |
| * |
| * NOTE - this interface is depreciated, and will go away. Use |
| * the eh_ routines instead. |
| */ |
| int (* reset)(Scsi_Cmnd *, unsigned int); |
| |
| /* |
| * This function is used to select synchronous communications, |
| * which will result in a higher data throughput. Not implemented |
| * yet. |
| */ |
| int (* slave_attach)(int, 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 number, list (heads, sectors, cylinders) |
| */ |
| int (* bios_param)(Disk *, kdev_t, int []); |
| |
| |
| /* |
| * Used to set the queue depth for a specific device. |
| */ |
| void (*select_queue_depths)(struct Scsi_Host *, Scsi_Device *); |
| |
| /* |
| * 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. |
| */ |
| short unsigned int sg_tablesize; |
| |
| /* |
| * if the host adapter has limitations beside segment count |
| */ |
| short unsigned int max_sectors; |
| |
| /* |
| * 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; |
| |
| unsigned highmem_io:1; |
| |
| /* |
| * Name of proc directory |
| */ |
| char *proc_name; |
| |
| } Scsi_Host_Template; |
| |
| /* |
| * The scsi_hosts array is the array containing the data for all |
| * possible <supported> scsi hosts. This is similar to the |
| * Scsi_Host_Template, except that we have one entry for each |
| * actual physical host adapter on the system, stored as a linked |
| * list. Note that if there are 2 aha1542 boards, then there will |
| * be two Scsi_Host entries, but only 1 Scsi_Host_Template entry. |
| */ |
| |
| struct Scsi_Host |
| { |
| /* private: */ |
| /* |
| * This information is private to the scsi mid-layer. Wrapping it in a |
| * struct private is a way of marking it in a sort of C++ type of way. |
| */ |
| struct Scsi_Host * next; |
| Scsi_Device * host_queue; |
| |
| spinlock_t default_lock; |
| spinlock_t *host_lock; |
| |
| struct task_struct * ehandler; /* Error recovery thread. */ |
| struct semaphore * eh_wait; /* The error recovery thread waits on |
| this. */ |
| struct semaphore * eh_notify; /* wait for eh to begin */ |
| 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. */ |
| wait_queue_head_t host_wait; |
| Scsi_Host_Template * hostt; |
| atomic_t host_active; /* commands checked out */ |
| volatile unsigned short host_busy; /* commands actually active on low-level */ |
| volatile unsigned short host_failed; /* commands that failed. */ |
| |
| /* public: */ |
| 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; |
| |
| /* These parameters should be set by the detect routine */ |
| unsigned long base; |
| unsigned long io_port; |
| unsigned char n_io_port; |
| unsigned char dma_channel; |
| unsigned int irq; |
| |
| /* |
| * 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 rest can be copied from the template, or specifically |
| * initialized, as required. |
| */ |
| |
| /* |
| * 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 in_recovery:1; |
| unsigned unchecked_isa_dma:1; |
| unsigned use_clustering:1; |
| unsigned highmem_io:1; |
| |
| /* |
| * Host has rejected a command because it was busy. |
| */ |
| unsigned host_blocked: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; |
| |
| /* |
| * Indicates that one or more devices on this host were starved, and |
| * when the device becomes less busy that we need to feed them. |
| */ |
| unsigned some_device_starved:1; |
| |
| void (*select_queue_depths)(struct Scsi_Host *, Scsi_Device *); |
| |
| /* |
| * For SCSI hosts which are PCI devices, set pci_dev so that |
| * we can do BIOS EDD 3.0 mappings |
| */ |
| struct pci_dev *pci_dev; |
| |
| /* |
| * 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)))); |
| }; |
| |
| /* |
| * 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(Scsi_Device * SDpnt); |
| extern Scsi_Device * scsi_get_host_dev(struct Scsi_Host * SHpnt); |
| |
| extern void scsi_unblock_requests(struct Scsi_Host * SHpnt); |
| extern void scsi_block_requests(struct Scsi_Host * SHpnt); |
| extern void scsi_report_bus_reset(struct Scsi_Host * SHpnt, int channel); |
| |
| typedef struct SHN |
| { |
| struct SHN * next; |
| char * name; |
| unsigned short host_no; |
| unsigned short host_registered; |
| } Scsi_Host_Name; |
| |
| extern Scsi_Host_Name * scsi_host_no_list; |
| extern struct Scsi_Host * scsi_hostlist; |
| extern struct Scsi_Device_Template * scsi_devicelist; |
| |
| extern Scsi_Host_Template * scsi_hosts; |
| |
| extern void build_proc_dir_entries(Scsi_Host_Template *); |
| |
| /* |
| * scsi_init initializes the scsi hosts. |
| */ |
| |
| extern int next_scsi_host; |
| |
| unsigned int scsi_init(void); |
| extern struct Scsi_Host * scsi_register(Scsi_Host_Template *, int j); |
| extern void scsi_unregister(struct Scsi_Host * i); |
| extern void scsi_register_blocked_host(struct Scsi_Host * SHpnt); |
| extern void scsi_deregister_blocked_host(struct Scsi_Host * SHpnt); |
| |
| static inline void scsi_assign_lock(struct Scsi_Host *host, spinlock_t *lock) |
| { |
| host->host_lock = lock; |
| } |
| |
| static inline void scsi_set_pci_device(struct Scsi_Host *SHpnt, |
| struct pci_dev *pdev) |
| { |
| SHpnt->pci_dev = pdev; |
| } |
| |
| |
| /* |
| * Prototypes for functions/data in scsi_scan.c |
| */ |
| extern void scan_scsis(struct Scsi_Host *shpnt, |
| uint hardcoded, |
| uint hchannel, |
| uint hid, |
| uint hlun); |
| |
| extern void scsi_mark_host_reset(struct Scsi_Host *Host); |
| |
| #define BLANK_HOST {"", 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} |
| |
| struct Scsi_Device_Template |
| { |
| struct Scsi_Device_Template * next; |
| const char * name; |
| const char * tag; |
| struct module * module; /* Used for loadable modules */ |
| unsigned char scsi_type; |
| unsigned int major; |
| unsigned int min_major; /* Minimum major in range. */ |
| unsigned int max_major; /* Maximum major in range. */ |
| unsigned int nr_dev; /* Number currently attached */ |
| unsigned int dev_noticed; /* Number of devices detected. */ |
| unsigned int dev_max; /* Current size of arrays */ |
| unsigned blk:1; /* 0 if character device */ |
| int (*detect)(Scsi_Device *); /* Returns 1 if we can attach this device */ |
| int (*init)(void); /* Sizes arrays based upon number of devices |
| * detected */ |
| void (*finish)(void); /* Perform initialization after attachment */ |
| int (*attach)(Scsi_Device *); /* Attach devices to arrays */ |
| void (*detach)(Scsi_Device *); |
| int (*init_command)(Scsi_Cmnd *); /* Used by new queueing code. |
| Selects command for blkdevs */ |
| }; |
| |
| void scsi_initialize_queue(Scsi_Device * SDpnt, struct Scsi_Host * SHpnt); |
| |
| |
| /* |
| * Driver registration/unregistration. |
| */ |
| extern int scsi_register_device(struct Scsi_Device_Template *); |
| extern int scsi_unregister_device(struct Scsi_Device_Template *); |
| extern int scsi_register_host(Scsi_Host_Template *); |
| extern int scsi_unregister_host(Scsi_Host_Template *); |
| |
| |
| /* |
| * This is an ugly hack. If we expect to be able to load devices at run time, |
| * we need to leave extra room in some of the data structures. Doing a |
| * realloc to enlarge the structures would be riddled with race conditions, |
| * so until a better solution is discovered, we use this crude approach |
| * |
| * Even bigger hack for SparcSTORAGE arrays. Those are at least 6 disks, but |
| * usually up to 30 disks, so everyone would need to change this. -jj |
| * |
| * Note: These things are all evil and all need to go away. My plan is to |
| * tackle the character devices first, as there aren't any locking implications |
| * in the block device layer. The block devices will require more work. |
| * |
| * The generics driver has been updated to resize as required. So as the tape |
| * driver. Two down, two more to go. |
| */ |
| #ifndef CONFIG_SD_EXTRA_DEVS |
| #define CONFIG_SD_EXTRA_DEVS 2 |
| #endif |
| #ifndef CONFIG_SR_EXTRA_DEVS |
| #define CONFIG_SR_EXTRA_DEVS 2 |
| #endif |
| #define SD_EXTRA_DEVS CONFIG_SD_EXTRA_DEVS |
| #define SR_EXTRA_DEVS CONFIG_SR_EXTRA_DEVS |
| |
| #endif |
| /* |
| * Overrides for Emacs so that we follow Linus's tabbing style. |
| * Emacs will notice this stuff at the end of the file and automatically |
| * adjust the settings for this buffer only. This must remain at the end |
| * of the file. |
| * --------------------------------------------------------------------------- |
| * Local variables: |
| * c-indent-level: 4 |
| * c-brace-imaginary-offset: 0 |
| * c-brace-offset: -4 |
| * c-argdecl-indent: 4 |
| * c-label-offset: -4 |
| * c-continued-statement-offset: 4 |
| * c-continued-brace-offset: 0 |
| * indent-tabs-mode: nil |
| * tab-width: 8 |
| * End: |
| */ |