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AIX Version 4.3 Kernel and Subsystems Technical Reference, Volume 2
idedisk IDE Device Driver
Purpose
Supports the Integrated Device Electronics (IDE) fixed disk devices.
Syntax
#include <sys/devinfo.h>
#include <sys/ide.h>
Device-Dependent Subroutines
Typical fixed disk operations are implemented using the open, close, read, write, and ioctl subroutines.
open and close Subroutines
The standard open and close operations are supported by the idedisk device driver. The openx operation is not supported.
The readx and writex subroutines provide additional parameters affecting the raw data transfer. These subroutines pass the ext parameter, which specifies request options. The options are constructed by logically ORing zero or more of the following values:
| WRITEV |
Indicates a request for write verification. |
ioctl Subroutine
ioctl subroutine operations that are used for the idedisk device driver are:
| IOCINFO |
Returns the devinfo structure defined in the /usr/include/sys/devinfo.h file. The IOCINFO operation is the only operation defined for all device drivers that use the ioctl subroutine. The remaining operations discussed in this article are all specific to IDE fixed disk devices. |
| DKFORMAT |
The IDE disk device driver does not support low level formatting of an IDE disk. IDE disks are preformatted at the factory and should not be reformatted. Attempting to format an IDE disk will result in a -1 return code and errno set to EINVAL. |
Device Requirements
IDE fixed disks must support the following ATA commands. The commands' hexadecimal opcodes are specified in the parenthesis:
- Identify Device (EC)
- Set Features (EF)
- Intialize Drive Parameters (91)
- Read Sector(s) without retry (21)
- Read Sector(s) with retry (20)
- Write Sector(s) with retry (30)
- Read DMA with retry (C8)
- Write DMA with retry (CA)
- Read Verify with retry (40)
- Idle Immediate (95)
- Standby Immediate (94)
Error Conditions
Possible errno values for ioctl, open, read, and write subroutines when using the idedisk device driver include:
| EFAULT |
Indicates an illegal user address. |
| EINVAL |
Indicates one of the following circumstances:
- The read or write subroutine supplied an nbyte parameter that is not an even multiple of the block size.
- An unsupported ioctl subroutine operation was attempted.
- An attempt was made to configure a device that is still open.
- An illegal configuration command was requested.
- The data buffer length exceeded the maximum defined for a strategy operation.
- The HWRELOC or UNSAFEREL bits of the writex ext parameter were set.
|
| EIO |
Indicates one of the following circumstances:
- The target device cannot be located or is not responding.
- The target device has indicated an unrecovered hardware error.
|
| ENFILE |
Indicates the system file table was full. |
| ENODEV |
The specified fixed disk was not configured or does not exist. |
| ENXIO |
Indicates one of the following circumstances:
- The specified fixed disk was not opened.
- The ioctl subroutine supplied an invalid parameter.
- A read or write operation was attempted beyond the end of the fixed disk.
|
| EPERM |
Indicates the attempted subroutine requires appropriate authority. |
| ETIMEDOUT |
Indicates an I/O operation exceeded the given time-out value. |
| EWRPROTECT |
Indicates one of the following circumstances:
- An open operation requesting read/write mode was attempted on read-only media.
- A write operation was attempted to read-only media.
|
Reliability and Serviceability Information
The following classes of errors are reported by the IDE disk device driver:
| SOFTWARE ACCESS ERROR |
Indicates that the fixed disk was not ready to receive a command or that an unsupported command was requested. |
| HARDWARE ERROR |
Indicates an unrecoverable hardware failure occurred during command execution. |
| MEDIA ERROR |
Indicates an unrecoverable media error was encountered during command execution. This class of error includes bad blocks, missing sector IDs, missing address marks, recalibration failures, and uncorrectable data errors. |
| RECOVERED ERROR |
Indicates the command succeeded due to fixed disk or disk device driver retries. |
Error Record Values for Media Errors
The fields defined in the error record template for fixed disk media errors are:
| Comment |
Indicates fixed disk media error. |
| Class |
Equals a value of H, which indicates a hardware error. |
| Report |
Equals a value of True, which indicates this error should be included when an error report is generated. |
| Log |
Equals a value of True, which indicates an error log entry should be created when this error occurs. |
| Alert |
Equals a value of False, which indicates this error is not alertable. |
| Err_Type |
Equals a value of Perm, which indicates a permanent failure. |
| Err_Desc |
Equals a value of 1312, which indicates a disk operation failure. |
| Prob_Causes |
Equals the following values:
- E855, which indicates a disk problem
- 6330, which indicates a disk drive electronics
|
| Fail_Causes |
Equals the following values:
- EA77, which indicates a bad block detected
- EA78, which indicates an uncorrectable data error
- EA79, which indicates a requested secotr's id or address mark not found
- EA7A, which indicates a track 0 not found
|
| Fail_Actions |
Equals the following values:
- EC1B, which indicates verify disk's master and slave jumpers are properly set
- 0301, which indicates check cables ant its connections
- 0000, which indicates problem-determination procedures should be performed
|
| Detail_Data |
Equals a value of 72, EC35, HEX. This value indicates hexadecimal format. |
Note: The Detail_Data
field in the err_rec structure contains the idedisk_error_rec structure. The err_rec structure is defined in the /usr/include/sys/errids.h file. The idedisk_error_rec structure is defined in the /usr/include/sys/ide.h file.
The idedisk_error_rec structure contains the following fields:
| status_validity |
Contains bit flags indicating validity of status and error fields. |
| b_error |
Contains error value from buf structure. |
| b_flags |
Contains flag value from buf structure. |
| b_addr |
Contains buffer address from buf structure. |
| b_resid |
Contains residual byte count from buf structure. |
| ata |
Contains the IDE command that was sent to the IDE device. Also may contain command completion status. |
Error Record Values for Physical Volume Software Access
The fields defined in the error record template for fixed disk physical volume software access are:
| Comment |
Indicates fixed disk encountered a physical volume software error. |
| Class |
Equals a value of S, which indicates a software error. |
| Report |
Equals a value of True, which indicates this error should be included when an error report is generated. |
| Log |
Equals a value of True, which indicates an error log entry should be created when this error occurs. |
| Alert |
Equal to a value of FALSE, which indicates this error is notIDe alertable. |
| Err_Type |
Equals a value of Perm, which indicates a permanent failure. |
| Err_Desc |
Equals a value of 210F, which indicates a software error |
| Prob_Causes |
Equals the following:
- EA00, which indicates a software error
- 6330, which indicates a disk drive electronics failure
|
| Fail_Causes |
Equals the following values:
- 109B, which indicates an invalid memory request size
- EA7B, which indicates an ATA status error
|
| Fail_Actions |
Equals the following values:
- EC1B, which indicates verify disk's master and slave jumpers are properly set
- 0301, which indicates check cables and its connections
- 0000, which indicates problem-determination procedures should be performed
|
| Detail_Data |
Equals a value of 72, EC35, HEX. This value indicates hexadecimal format. |
Note: The Detail_Data
field in the err_rec structure contains the idedisk_error_rec structure. The err_rec structure is defined in the /usr/include/sys/errids.h file. The idedisk_error_rec structure is defined in the /usr/include/sys/ide.h file.
The idedisk_error_rec structure contains the following fields:
| status_validity |
Contains bit flags indicating validity of status and error fields. |
| b_error |
Contains error value from buf structure. |
| b_flags |
Contains flag value from buf structure. |
| b_addr |
Contains buffer address from buf structure. |
| b_resid |
Contains residual byte count from buf structure. |
| ata |
Contains the IDE command that was sent to the IDE device. Also may contain command completion status. |
Error Record Values for Physical Volume Hardware Error
The fields defined in the error record template for fixed disk physical volume hardware errors recovered errors are:
| Comment |
Indicates fixed disk physical volume hardware error |
| Class |
Equals a value of H, which indicates a hardware error. |
| Report |
Equals a value of True, which indicates this error should be included when an error report is generated. |
| Log |
Equals a value of True, which indicates an error log entry should be created when this error occurs. |
| Alert |
Equal to a value of FALSE, which indicates this error is not alertable. |
| Err_Type |
Equals a value of Perm, which indicates a permanent failure. |
| Err_Desc |
Equals a value of 1311, which indicates a physical volume operation failure |
| Prob_Causes |
Equals a value of 6330, which indicates a disk drive electronics failure |
| Fail_Causes |
Equals a value of EA7C, which indicates an invalide media-change status |
| Fail_Actions |
Equals the following values:
- EC1B, which indicates verify disk's master and slave jumpers are properly set
- 0301, which indicates check cables and its connections
- 0000, which indicates problem-determination procedures should be performed
- 1804, which indicates replace device
|
| Detail_Data |
Equals a value of 72, EC35, HEX. This value indicates hexadecimal format. |
Note: The Detail_Data
field in the err_rec structure contains the idedisk_error_rec structure. The err_rec structure is defined in the /usr/include/sys/errids.h file. The idedisk_error_rec structure is defined in the /usr/include/sys/ide.h file.
The idedisk_error_rec structure contains the following fields:
| b_error |
Contains error value from buf structure. |
| b_flags |
Contains flag value from buf structure. |
| b_addr |
Contains buffer address from buf structure. |
| b_resid |
Contains residual byte count from buf structure. |
| ata |
Contains the IDE command that was sent to the IDE device. Also may contain command completion status. |
Error Record Values for Physical Volume Recovered Error
The fields defined in the error record template for fixed disk physical volume recovered errors are:
| Comment |
Indicates fixed disk physical volume recovered error |
| Class |
Equals a value of H, which indicates a hardware error. |
| Report |
Equals a value of True, which indicates this error should be included when an error report is generated. |
| Log |
Equals a value of True, which indicates an error log entry should be created when this error occurs. |
| Alert |
Equal to a value of FALSE, which indicates this error is not alertable. |
| Err_Type |
Equals a value of Temp, which indicates the type of error is temporary. |
| Err_Desc |
Equals a value of EC64, which indicates a disk failure recovered during retry. |
| Prob_Causes |
Equals the following values:
- E855, which indicates an adapter failure
- 6330, which indicates a disk drive electronics failure
- EA00, which indicates a media failure
|
| Fail_Causes |
Equals the following values:
- 5000, which indicates a media failure
- EA7B, which indicates an IDE command error
- EA7C, which indicates an invalid media change
|
| Fail_Actions |
Equals a value of 0700, which indicates no action necessary |
| Detail_Data |
Equals a value of 72, EC35, HEX. This value indicates hexadecimal format. |
Note: The Detail_Data
field in the err_rec structure contains the idedisk_error_rec structure. The err_rec structure is defined in the /usr/include/sys/errids.h file. The idedisk_error_rec structure is defined in the /usr/include/sys/ide.h file.
The idedisk_error_rec structure contains the following fields:
| b_error |
Contains error value from buf structure. |
| b_flags |
Contains flag value from buf structure. |
| b_addr |
Contains buffer address from buf structure. |
| b_resid |
Contains residual byte count from buf structure. |
| ata |
Contains the IDE command that was sent to the IDE device. Also may contain command completion status. |
Special Files
The idedisk IDE device driver uses raw and block special files in performing its functions.
Attention: Data corruption, loss of data, or loss of system integrity (system crash) will occur if devices supporting paging, logical volumes, or mounted file systems are accessed using block special files. Block special files are provided for logical volumes and disk devices and are solely for system use in managing file systems, paging devices, and logical volumes. These files should not be used for other purposes.
The special files used to access the idedisk device driver include these fixed disk devices:
| /dev/rhdisk0, /dev/rhdisk1,..., /dev/rhdiskn |
Provide an interface to allow character access (raw I/O access and control functions) to IDE fixed disks. |
| /dev/hdisk0, /dev/hdisk1,..., /dev/hdiskn |
Provide an interface to allow block I/O access to IDE fixed disks. |
Note: The prefix r on a special file name indicates the drive is accessed as a raw device rather than a block device. Performing raw I/O with a fixed disk drive requires that all data transfers 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.
Related Information
Special Files Overview in AIX Version 4 Files Reference.
IDE Subsystem Overview in AIX Version 4.1 Kernel Extensions and Device Support Programming Concepts.
A Typical IDE Driver Transaction Sequence in AIX Version 4.1 Kernel Extensions and Device Support Programming Concepts.
Required IDE Adapter Device Driver ioctl Commands in AIX Version 4.1 Kernel Extensions and Device Support Programming Concepts.
Understanding the Execution of Initiator I/O Requests in AIX Version 4.1 Kernel Extensions and Device Support Programming Concepts.
IDE Error Recovery in AIX Version 4.1 Kernel Extensions and Device Support Programming Concepts.
ataide_buf Structure in AIX Version 4.1 Kernel Extensions and Device Support Programming Concepts.
IDE Adapter Device Driver.
The close subroutine, ioctl or ioctlx subroutine, open, openx, create subroutine, read, readx, readv, or readvx subroutine, write, writex, writev, or writevx subroutine.
rhdisk Special File.
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