userspace-api/ioctl/hdio.rst

5 - Edward A. Falk <efalk@google.com>
9 This document attempts to describe the ioctl(2) calls supported by
10 the HD/IDE layer.  These are by-and-large implemented (as of Linux 5.11)
11 drivers/ata/libata-scsi.c.
27     ioctls that pass non-pointer values:
37 ------------------------------------------------------------------------------
41 	Unless otherwise specified, all ioctl calls return 0 on success
42 	and -1 with errno set to an appropriate value on error.
44 	Unless otherwise specified, all ioctl calls return -1 and set
48 	Unless otherwise specified, all data structures and constants
51 ------------------------------------------------------------------------------
64 	inputs:
82 	  - EINVAL
94 		are the "bios" values -- presumably the values the drive had
117 	inputs:
128 	  - EINVAL	Called on a partition instead of the whole disk device
129 	  - ENOMSG	IDENTIFY DEVICE information not available
134 		this ioctl does not re-probe the drive to update the
151 	inputs:
162 		0=16-bit, 1=32-bit, 2,3 = 32bit+sync
174 	- Execute an ATA disk command directly by writing the "taskfile"
193 	inputs:
199 	  hob_ports[8]	high-order bytes, for extended commands.
213 	  hob_ports[]	high-order bytes, for extended commands.
214 	  out_flags	flags indicating which registers are valid (see [2])
221 	  - EACCES	CAP_SYS_ADMIN or CAP_SYS_RAWIO privilege not set.
222 	  - ENOMSG	Device is not a disk drive.
223 	  - ENOMEM	Unable to allocate memory for task
224 	  - EFAULT	req_cmd == TASKFILE_IN_OUT (not implemented as of 2.6.8)
225 	  - EPERM
228 			multi-count not yet set.
229 	  - EIO		Drive failed the command.
238 	  [2] Both the input and output buffers are copied from the
242 	  zero, the following values are used for in_flags.all and
250 	  The association between in_flags.all and each enable
252 	  only uses inflags.b.data bit and ignores all other bits.
272 	    hob_ports[8]	high-order bytes, for extended commands
282 	    out_size		output (user->drive) buffer size, bytes
283 	    in_size		input (drive->user) buffer size, bytes
308 				travel on DD8-DD15 on little endian machines
309 				and on DD0-DD7 on big endian machines.
311 				travel on DD0-DD7 on little endian machines
312 				and on DD8-DD15 on big endian machines.
332 	    2. One or more than one bits are set in out_flags.
337 				DD8-DD15 on little endian machines and
338 				DD0-DD7 on big endian machines.
340 				DD0-DD7 on little endian machines and
341 				DD8-DD15 on big endian machines.
385 	  [6] Do not access {in|out}_flags->all except for resetting
386 	  all the bits.  Always access individual bit fields.  ->all
407 	inputs:
413 	    args[2]	FEATURE
422 	    args[2]	FEATURE
435 	    args[2]	NSECTOR
441 	  - EACCES	Access denied:  requires CAP_SYS_RAWIO
442 	  - ENOMEM	Unable to allocate memory for task
443 	  - EIO		Drive reports error
454 	  [2] If NSECTOR value is greater than zero and the drive sets
482 	inputs:
488 	    args[2]	NSECTOR
502 	    args[2]	NSECTOR
510 	  - EACCES	Access denied:  requires CAP_SYS_RAWIO
511 	  - ENOMEM	Unable to allocate memory for task
512 	  - ENOMSG	Device is not a disk drive.
513 	  - EIO		Drive failed the command.
518 	  appropriate value for the drive is used.  All other bits
533 	inputs:
544 	  - EINVAL	Called on a partition instead of the whole disk device
545 	  - EACCES	Access denied:  requires CAP_SYS_ADMIN
546 	  - EINVAL	value out of range [0 3]
547 	  - EBUSY	Controller busy