dad(7D) 							      Devices								   dad(7D)

NAME

       dad - driver for IDE disk devices

SYNOPSIS

       dad@ target,lun:partition

DESCRIPTION

       This  driver handles the ide disk drives on SPARC platforms. The type of disk drive is determined using the ATA IDE identify device command
       and by reading the volume label stored on block 0 of the  drive. The volume label describes the disk geometry and partitioning; it must	be
       present or the disk cannot be mounted by the system.

       The  block-files  access  the  disk using the system's normal buffering mechanism and are read and written without  regard to physical disk
       records. There is also a "raw" interface that provides for direct transmission between the disk and the user's read  or	write  buffer.	 A
       single read or write call usually results in one I/O operation; raw I/O is therefore considerably more efficient when many bytes are trans-
       mitted.	The names of the block files are found in /dev/dsk; the names of the raw files are found in  /dev/rdsk.

       I/O requests to the raw device must be aligned on a 512-byte (DEV_BSIZE) boundary and must have a length that is a multiple of  512  bytes.
       Requests  which	do  not  meet  the restrictions will cause the driver to return an  EINVAL error. I/O requests to the block device have no
       alignment or length restrictions.

   Device Statistics Support
       Each device maintains I/O statistics both for the device and for each partition allocated on that device. For  each  device/partition,  the
       driver  accumulates reads, writes, bytes read, and bytes written.  The driver also takes  hi-resolution time stamps at queue entry and exit
       points, which facilitates monitoring the residence time and cumulative  residence-length product for each queue.

       Each device also has error statistics associated with it. These must include counters for hard errors, soft errors  and	transport  errors.
       Other data may be implemented as required.

FILES

       /dev/dsk/cntndnsn       block files

       /dev/rdsk/cntndnsn      raw files

       where:

       cn	controller  n

       tn	IDE target id  n (0-3)

       dn	Always 0.

       sn	partition  n (0-7)

       The target ide numbers are assigned as:

       0	Master disk on Primary channel.

       1	Slave disk on Primary channel.

       2	Master disk on Secondary channel

       3	Slave disk on Secondary channel.

IOCTLS

       Refer to  dkio(7I).

ERRORS

       EACCES	       Permission denied.

       EBUSY	       The partition was opened exclusively by another thread.

       EFAULT	       The argument was a bad address.

       EINVAL	       Invalid argument.

       EIO	       An I/O error occurred.

       ENOTTY	       This indicates that the device does not	support the requested ioctl function.

       ENXIO	       During opening, the device did not exist.

       EROFS	       The device is a read-only device.

SEE ALSO

       format(1M), mount(1M), lseek(2), read(2), write(2), driver.conf(4), vfstab(4), dkio(7I)

       X3T10 ATA-4 specifications.

DIAGNOSTICS

       Command:<number>, Error:<number>, Status:<number>

	   Indicates that the command failed with an error and provides status register contents. Where <number> is a hexadecimal value.

       offline

	   The driver has decided that the target disk is no longer there.

       disk ok

	   The target disk is now responding again.

       corrupt label - bad geometry

	   The disk label is corrupted.

       corrupt label - label checksum failed

	   The disk label is corrupted.

       corrupt label - wrong magic number

	   The disk label is corrupted.

       disk not responding to selection

	   The target disk is not responding.

       i/o to invalid geometry

	   The geometry of the drive could not be established.

       incomplete read/write - retrying/giving up

	   There was a residue after the command completed normally.

       no bp for disk label

	   A bp with consistent memory could not be allocated.

       no memory for disk label

	   Free memory pool exhausted.

       ATA transport failed: reason 'nnnn': {retrying|giving}

	   The	host  adapter  has failed to transport a command to the target for the reason stated. The driver will either retry the command or,
	   ultimately, give up.

       corrupt label - wrong magic number

	   The disk label is corrupted.

       corrupt label - label checksum failed

	   The disk label is corrupted.

       corrupt label - bad geometry

	   The disk label is corrupted.

       no mem for property

	   Free memory pool exhausted.

       transport rejected (<n>)

	   Host adapter driver was unable to accept a command.

       Device Fault

	   There has been a Device Fault - reason for such error is vendor specific.

SunOS 5.10							    15 Mar 2004 							   dad(7D)