IBM Advanced SerialRAID Adapters SA33-3285-02, User Manual

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ENOMEM
The system does not have enough real memory or enough paging space to
complete the operation.
ENOLCK
An attempt was made to open a device in Service mode, and the device is in
an SSA network that is not a loop.
Special Files
The ssadisk device driver uses raw and block special files to perform its functions.
Attention: Corruption of data, loss of data, or loss of system integrity (system crash)
occurs if block special files are used to access devices that provide support for paging,
logical volumes, or mounted file systems. Block special files are provided for logical
volumes and for disk devices. They must be used only by the using system for
managing file systems, for paging devices, and for logical volumes. These files should
not be used for other purposes.
The special files that the ssadisk device driver uses include the following (listed by type
of device):
v
SSA logical disk drives:
/dev/hdisk0, /dev/hdisk1,..., /dev/hdiskn
Provide an interface that allows SSA device drivers to have block I/O access
to logical SSA disk drives.
/dev/rhdisk0, /dev/rhdisk1,..., /dev/rhdiskn
Provide an interface that allows SSA device drivers to have character
access (raw I/O access and control functions) to logical SSA disk drives.
v
SSA physical disk drives:
/dev/pdisk0, /dev/pdisk1, ..., /dev/pdiskn
Provide an interface that allows SSA device drivers to have character
access (control functions only) to physical SSA disk drives.
Note: The prefix r on a special file name indicates that the drive is accessed as a raw
device rather than as a block device. To perform raw I/O with an SSA logical
disk, all data transfers must be in multiples of the device block size. Also, all
lseek subroutines that are made to the raw device driver must result in a file
pointer value that is a multiple of the device block size.
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