rtfsinit.c

ertfs文件系统里面既有完整ucos程序

/******************************************************************************
    PC_ERTFS_INIT() - Configure ERTFS drive letter/device mapping and initialize 
    device drivers.
    

    The user must modify this code to assign parameters and bind device 
    driver entry points to ERTFS drive structures. The source code contains 
    examples for configuring each of the stock device drivers.

    This routine initializes ERTFS resources and binds device drivers to drive 
    letters so it must must be called before any other calls to the ERTFS 
    API are made. 


    Device driver configuration block. 

    The ERTFS drive structure (struct ddrive) contains a section that must be
    initialized by the user. 
    
    The following fields must be initialized -

    register_file_address   - IO address pointer that may be used by the 
    device driver to access the controller. For the stock set of drivers
    only the IDE/ATAPI driver use this parameter.
    interrupt_number        - Interrupt vector number that the controller 
    will interrupt on.
    drive_flags             - The user sets bits in this field to tell ERTFS
    and the device driver about the drive's properties. The device driver
    uses this field to keep track of the device status.

    These two bits may be set by the user in the main body of the 
    the pc_ertfs_init routine.

    DRIVE_FLAGS_PARTITIONED - Set this bit if the device is a partitioned
    device.
    DRIVE_FLAGS_PCMCIA      - Set this bit if the device is a pcmcia device.
    ERTFS does not look at this bit. It is used ony by the device drivers.

    These bits are set by device driver.

    DRIVE_FLAGS_VALID -  Set by the driver in the WARMSTART IO Control
    call if  initialization succeeded. If this flags is not set then ERTFS
    will not call the driver again.

    DRIVE_FLAGS_REMOVABLE - Set by the device driver init routine if the 
    device is removable. If this bit is set then the driver must implement
    the DEVCTL_CHECKSTATUS ioctrl function.

    DRIVE_FLAGS_INSERTED - This bit is used by the device driver to maintain 
    state information. This bit is used by the PCMCIA drivers in the 
    following way. The default value is ZERO. If this value is zero when the
    check status IOCTRL call is made then the driver attempts to map the
    device through the pcmcia controller. The pcmcia management interrupt 
    routine clears this bit when a card removal occurs.

    partition_number    - If DRIVE_FLAGS_PARTITIONED is set in the 
    drive_flags field then this must be initialized with the partition
    number. 0,1,2 etc.
    lock_unit           - ERTFS maintains a set of lock semaphores to protect
    controller code from code re-entrancy. This value must be initialized by
    the user with the semaphore number to lock before accessing this device, 
    (0 to (NDRIVES-1)).  If two device drivers must share the same resource and
    access to that resource is not re-entrant then they should use the same
    lock unit.
    pcmcia_slot_number  - If DRIVE_FLAGS_PCMCIA is set then this tells which
    pcmcia slot. Must be (0 or 1) for the supplied PCMCIA subsystem.
    pcmcia_controller_number - If DRIVE_FLAGS_PCMCIA is set then this tells 
    which controller.  Must be (0) for the supplied PCMCIA subsystem.
    pcmcia_cfg_opt_value - This is the value to be place in the card's 
    configuration option register by the pcmcia driver after power up.
    controller_number   - This is set by the user in init and used by
    driver to access controller specific information. For example the ide
    device driver supports two controllers. This value is used by the driver
    to store controller specific data and calculate controller specific
    addresses and values.
    logical_unit_number - This is a logical unit number that is used only 
    by the device driver. For example the IDE driver uses logical unit 
    number 1 to access the slave drive. The floppy disk uses logical 
    unit 1 to access the secondary floppy.
    driveno - This is the drive number that the user wishes ERTFS to access 
    this device as. 0 = A:, 1 = B: etc. 


    dev_table_drive_io  - This is the io function for the device. The 
    function must perform the requested read or write operation and 
    return the correct status (TRUE for success, FALSE for failure).

    By example here is the ide drive io function.
    
        BOOLEAN ide_io(driveno, sector, buffer, count, BOOLEAN reading)
        int driveno - 0 to NDRIVES == A:,B:,.. the driver calls
        pc_drno_to_drive_struct(driveno) to access the drive structure.
        dword sector- Starting sector number to read or write
        void *buffer- Buffer to read to write from.
        word count  - Number of sectors to transfer
        reading     - True for a read request, False for a write request.

    dev_table_perform_device_ioctl - This is the control interface to the 
    device driver.

    By example here is the ide drive io control function.

    int ide_perform_device_ioctl(driveno, opcode, pargs)
        int driveno - 0 to NDRIVES == A:,B:,.. the driver calls
        pc_drno_to_drive_struct(driveno) to access the drive structure.
        int opcode - One of the following:
            DEVCTL_CHECKSTATUS
            DEVCTL_WARMSTART
            DEVCTL_POWER_RESTORE
            DEVCTL_POWER_LOSS
            DEVCTL_GET_GEOMETRY
            DEVCTL_FORMAT
            DEVCTL_REPORT_REMOVE
        PFVOID pargs - void pointer to arguments. See details below.

            Here are detailed descriptions of each OPCODE and its relation
            to pargs.

            DEVCTL_CHECKSTATUS  - Return the status of device. ERTFS calls
            the driver with this opcode before it performs IO.

            Note: For the CHECKSTATUS call. ERTFS will pass a BOOLEAN value
            to the driver to indicate if the volume in question has unwritten
            cached data that will be lost if the driver returns anything but
            DEVTEST_NOCHANGE. If this value is true then the driver may 
            make more aggresive efforts to correct media changes. For example
            by asking the user to re-insert the correct diskette or card.

            The driver must return one of the following values:
            DEVTEST_NOCHANGE - The device is available and no media change
            has been detected since the previous CHECKSTATUS call.
            DEVTEST_NOMEDIA  - The device contains no media.
            DEVTEST_UNKMEDIA - The device contains media but the driver
            can not read or write to it.
            DEVTEST_CHANGED  - The device is available to but a media change
            has been detected since the previous CHECKSTATUS call. ERTFS will 
            close out the current logical volume and re-mount the device.

            DEVCTL_WARMSTART - The device driver is called with this opcode
            once at startup. For non removable media the device should verify
            that the device is accessable and if so set the DRIVE_FLAGS_VALID
            bit. For removable media the device should verify that the device
            controller is accessable and if so set the DRIVE_FLAGS_VALID and
            DRIVE_FLAGS_REMOVABLE bits. pargs is not used.

            DEVCTL_POWER_RESTORE - Tell the device driver that system power 
            has been restored. The driver should attempt to restore the 
            device to the "UP" state. ERTFS never calls the driver with this 
            opcode. System integrators may call it to inform the driver of
            power restore. pargs is not used.

            DEVCTL_POWER_LOSS - Tell the device driver that system power 
            has been lost or will soon be lost. The driver should attempt to
            go into low power mode. ERTFS never calls the driver with this 
            opcode. System integrators may call it to inform the driver of
            power loss. pargs is not used.

            DEVCTL_GET_GEOMETRY  - ERTFS calls this routine to get the values
            it will use to partition and format volumes.
            pargs points to a structure of type DEV_GEOMETRY. The driver 
            should fill in the values as defined below.
            typedef struct dev_geometry {
            -  Geometry in HCN format
            int dev_geometry_heads;      - Must be < 256
            int dev_geometry_cylinders;  - Must be < 1024
            int dev_geometry_secptrack;  - Must be < 64
            BOOLEAN fmt_parms_valid;   If the device io control call sets 
                                       this TRUE then it it telling the 
                                       the format parameters are valid
                                       and should be used. This is a way to
                                       format floppy disks exactly as they
                                       are formatted by dos.
            FMTPARMS fmt;
            } DEV_GEOMETRY;
            
            DEVCTL_FORMAT       - ERTFS calls this routine to physically 
            format the device. pargs points to the DEV_GEOMETRY structure
            that was returned from the GET_GEOMETRY call. The device driver
            should physically format the device if needed.

            DEVCTL_REPORT_REMOVE - This can be called by an external 
            interrupt to tell the driver that the device has been removed.
            The pcmcia management interrupt calls this and the pcmcia aware
            drivers, PCMSRAM.C and IDE_DRV.C, clear the DRIVE_FLAGS_INSERTED
            bit in the drive structure. They later query this from the 
            CHECKSTATUS code. pargs is not used.

*/
#include "pcdisk.h"




/* This is used only in this file set it to 0 if you don't want to 
   print the names of the drivers as they are mounted */  
#define PRINT_DEVNAMES 1

#if (PRINT_DEVNAMES)
char *dev_name[NDRIVES];
#define SAVE_NAME(LOGIGAL_DRIVE_NUMBER,STRING)  dev_name[LOGIGAL_DRIVE_NUMBER] = STRING;
#endif

BOOLEAN pc_ertfs_init(void)
{
int j;
DDRIVE *pdr;
int lock_unit = 0;
word logical_drive_number;

    if (!pc_memory_init())
        return(FALSE);

#if (PRINT_DEVNAMES)
    for (j = 0; j < NDRIVES; j++, pdr++)
        dev_name[j] = 0;
#endif

    pdr = mem_drives_structures;
    
    /* User initialization section */