dad(7D) (man pages section 7: Device and Network Interfaces)

man pages section 7: Device and Network Interfaces

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 transmitted. 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.

DIAGNOSTICS

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 5.9 Last Revised 15 Mar 1999