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Document the new generic memory range management ioctls.

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This commit is contained in:
msmith 1999-04-07 04:03:51 +00:00
parent 5fe70bcd61
commit bcea080ba2
2 changed files with 222 additions and 2 deletions
share/man/man4
man4.i386
mem.4
mem.4

112
share/man/man4/man4.i386/mem.4

@ -30,7 +30,7 @@
.\" SUCH DAMAGE.
.\"
.\" @(#)mem.4 5.3 (Berkeley) 5/2/91
.\" $Id$
.\" $Id: mem.4,v 1.3 1997/03/07 02:49:51 jmg Exp $
.\"
.Dd May 2, 1991
.Dt MEM 4 i386
@ -70,14 +70,124 @@ is
.Dv UPAGES
long, and ends at virtual
address 0xf0000000.
.Sh IOCTL INTERFACE
Several architectures allow attributes to be associated with ranges of physical
memory. These attributes can be manipulated via
.Fn ioctl
calls performed on
.Nm /dev/mem .
Declarations and data types are to be found in
.Pa <memrange.h>
.Pp
The specific attributes, and number of programmable ranges may vary between
architectures. The full set of supported attributes is:
.Bl -tag -width 10
.It MDF_UNCACHEABLE
The region is not cached.
.It MDF_WRITECOMBINE
Writes to the region may be combined or performed out of order.
.It MDF_WRITETHROUGH
Writes to the region are committed synchronously.
.It MDF_WRITEBACK
Writes to the region are committed asynchronously.
.It MDF_WRITEPROTECT
The region cannot be written to.
.El
.Pp
Memory ranges are described by
.Fa struct mem_range_desc :
.Bd -literal -offset indent
u_int64_t mr_base; /\(** physical base address \(**/
u_int64_t mr_len; /\(** physical length of region \(**/
int mr_flags; /\(** attributes of region \(**/
char mr_owner[8];
.Ed
.Pp
In addition to the region attributes listed above, the following flags
may also be set in the
.Fa mr_flags
field:
.Bl -tag -width 10
.It MDF_FIXBASE
The region's base address cannot be changed.
.It MDF_FIXLEN
The region's length cannot be changed.
.It MDF_FIRMWARE
The region is believed to have been established by the system firmare.
.It MDF_ACTIVE
The region is currently active.
.It MDF_BOGUS
We believe the region to be invalid or otherwise erroneous.
.It MDF_FIXACTIVE
The region cannot be disabled.
.It MDF_BUSY
The region is currently owned by another process and may not be
altered.
.El
.Pp
Operations are performed using
.Fa struct mem_range_op :
.Bd -literal -offset indent
struct mem_range_desc *mo_desc;
int mo_arg[2];
.Ed
.Pp
The
.Fa MEMRANGE_GET
ioctl is used to retrieve current memory range attributes. If
.Fa mo_arg[0]
is set to 0, it will be updated with the total number of memory range
descriptors. If greater than 0, the array at
.Fa mo_desc
will be filled with a corresponding number of descriptor structures,
or the maximum, whichever is less.
.Pp
The
.Fa MEMRANGE_SET
ioctl is used to add, alter and remove memory range attributes. A range
with the MDF_FIXACTIVE flag may not be removed; a range with the MDF_BUSY
flag may not be removed or updated.
.Pp
.Fa mo_arg[0]
should be set to MEMRANGE_SET_UPDATE to update an existing
or establish a new range, or to MEMRANGE_SET_REMOVE to remove a range.
.Pp
.Sh RETURN VALUES
.Bl -tag -width 10
.It EOPNOTSUPP
Memory range operations are not supported on this architecture.
.It ENXIO
No memory range descriptors are available (eg. firmware has not enabled
any).
.It EINVAL
The memory range supplied as an argument is invalid or overlaps another
range in a fashion not supported by this architecture.
.It EBUSY
An attempt to remove or update a range failed because the range is busy.
.It ENOSPC
An attempt to create a new range failed due to a shortage of hardware
resources (eg. descriptor slots).
.It ENOENT
An attempt to remove a range failed because no range matches the descriptor
base/length supplued.
.It EPERM
An attempt to remove a range failed because the range is permanently
enabled.
.El
.Sh BUGS
Busy range attributes are not yet managed correctly.
.Sh FILES
.Bl -tag -width Pa -compact
.It Pa /dev/mem
.It Pa /dev/kmem
.El
.Sh SEE ALSO
.Xr memcontrol 8
.Sh HISTORY
The
.Nm mem ,
.Nm kmem
files appeared in
.At v6 .
The ioctl interface for memory range attributes was added in
.Fx 3.2 .

112
share/man/man4/mem.4

@ -30,7 +30,7 @@
.\" SUCH DAMAGE.
.\"
.\" @(#)mem.4 5.3 (Berkeley) 5/2/91
.\" $Id$
.\" $Id: mem.4,v 1.3 1997/03/07 02:49:51 jmg Exp $
.\"
.Dd May 2, 1991
.Dt MEM 4 i386
@ -70,14 +70,124 @@ is
.Dv UPAGES
long, and ends at virtual
address 0xf0000000.
.Sh IOCTL INTERFACE
Several architectures allow attributes to be associated with ranges of physical
memory. These attributes can be manipulated via
.Fn ioctl
calls performed on
.Nm /dev/mem .
Declarations and data types are to be found in
.Pa <memrange.h>
.Pp
The specific attributes, and number of programmable ranges may vary between
architectures. The full set of supported attributes is:
.Bl -tag -width 10
.It MDF_UNCACHEABLE
The region is not cached.
.It MDF_WRITECOMBINE
Writes to the region may be combined or performed out of order.
.It MDF_WRITETHROUGH
Writes to the region are committed synchronously.
.It MDF_WRITEBACK
Writes to the region are committed asynchronously.
.It MDF_WRITEPROTECT
The region cannot be written to.
.El
.Pp
Memory ranges are described by
.Fa struct mem_range_desc :
.Bd -literal -offset indent
u_int64_t mr_base; /\(** physical base address \(**/
u_int64_t mr_len; /\(** physical length of region \(**/
int mr_flags; /\(** attributes of region \(**/
char mr_owner[8];
.Ed
.Pp
In addition to the region attributes listed above, the following flags
may also be set in the
.Fa mr_flags
field:
.Bl -tag -width 10
.It MDF_FIXBASE
The region's base address cannot be changed.
.It MDF_FIXLEN
The region's length cannot be changed.
.It MDF_FIRMWARE
The region is believed to have been established by the system firmare.
.It MDF_ACTIVE
The region is currently active.
.It MDF_BOGUS
We believe the region to be invalid or otherwise erroneous.
.It MDF_FIXACTIVE
The region cannot be disabled.
.It MDF_BUSY
The region is currently owned by another process and may not be
altered.
.El
.Pp
Operations are performed using
.Fa struct mem_range_op :
.Bd -literal -offset indent
struct mem_range_desc *mo_desc;
int mo_arg[2];
.Ed
.Pp
The
.Fa MEMRANGE_GET
ioctl is used to retrieve current memory range attributes. If
.Fa mo_arg[0]
is set to 0, it will be updated with the total number of memory range
descriptors. If greater than 0, the array at
.Fa mo_desc
will be filled with a corresponding number of descriptor structures,
or the maximum, whichever is less.
.Pp
The
.Fa MEMRANGE_SET
ioctl is used to add, alter and remove memory range attributes. A range
with the MDF_FIXACTIVE flag may not be removed; a range with the MDF_BUSY
flag may not be removed or updated.
.Pp
.Fa mo_arg[0]
should be set to MEMRANGE_SET_UPDATE to update an existing
or establish a new range, or to MEMRANGE_SET_REMOVE to remove a range.
.Pp
.Sh RETURN VALUES
.Bl -tag -width 10
.It EOPNOTSUPP
Memory range operations are not supported on this architecture.
.It ENXIO
No memory range descriptors are available (eg. firmware has not enabled
any).
.It EINVAL
The memory range supplied as an argument is invalid or overlaps another
range in a fashion not supported by this architecture.
.It EBUSY
An attempt to remove or update a range failed because the range is busy.
.It ENOSPC
An attempt to create a new range failed due to a shortage of hardware
resources (eg. descriptor slots).
.It ENOENT
An attempt to remove a range failed because no range matches the descriptor
base/length supplued.
.It EPERM
An attempt to remove a range failed because the range is permanently
enabled.
.El
.Sh BUGS
Busy range attributes are not yet managed correctly.
.Sh FILES
.Bl -tag -width Pa -compact
.It Pa /dev/mem
.It Pa /dev/kmem
.El
.Sh SEE ALSO
.Xr memcontrol 8
.Sh HISTORY
The
.Nm mem ,
.Nm kmem
files appeared in
.At v6 .
The ioctl interface for memory range attributes was added in
.Fx 3.2 .