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2005-06-17 Joel Sherrill <joel@OARcorp.com>

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* user/region.t: Add documentation on region_resize_segment.
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Joel Sherrill
2005-06-17 14:29:13 +00:00
parent df8ba46d8e
commit a9d5d449a1
2 changed files with 71 additions and 0 deletions
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doc/ChangeLog
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@@ -1,3 +1,7 @@
2005-06-17 Joel Sherrill <joel@OARcorp.com>
* user/region.t: Add documentation on region_resize_segment.
2005-04-28 Joel Sherrill <joel@OARcorp.com>
* bsp_howto/rtc.t: Rewritten to account for removal of dmv177.

67
doc/user/region.t
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@@ -24,6 +24,7 @@ provided by the region manager are:
@item @code{@value{DIRPREFIX}region_get_segment} - Get segment from a region
@item @code{@value{DIRPREFIX}region_return_segment} - Return segment to a region
@item @code{@value{DIRPREFIX}region_get_segment_size} - Obtain size of a segment
@item @code{@value{DIRPREFIX}region_resize_segment} - Change size of a segment
@end itemize
@section Background
@@ -202,6 +203,15 @@ size in bytes of the specified segment. The size returned
includes any "extra" memory included in the segment because of
rounding up to a page size boundary.
@subsection Changing the Size of a Segment
The @code{@value{DIRPREFIX}region_resize_segment} directive
is used to change the size in bytes of the specified segment. The
size may be increased or decreased. When increasing the
size of a segment, it is possible that the request cannot be
satisfied. This directive is used to support the @code{realloc()}
function in the Standard C Library.
@subsection Deleting a Region
A region can be removed from the system and returned
@@ -663,3 +673,60 @@ The actual length of the allocated segment may be
larger than the requested size because a segment size is always
a multiple of the region's page size.
@c
@c
@c
@page
@subsection REGION_RESIZE_SEGMENT - Change size of a segment
@cindex resize segment
@subheading CALLING SEQUENCE:
@ifset is-C
@findex rtems_region_resize_segment
@example
rtems_status_code rtems_region_resize_segment(
rtems_id id,
void *segment,
size_t size,
size_t *old_size
);
@end example
@end ifset
@ifset is-Ada
@example
procedure Region_Resize_Segment (
ID : in RTEMS.ID;
Segment : in RTEMS.Address;
Size : in RTEMS.Unsigned32;
Old_Size : out RTEMS.Unsigned32;
Result : out RTEMS.Status_Codes
);
@end example
@end ifset
@subheading DIRECTIVE STATUS CODES:
@code{@value{RPREFIX}SUCCESSFUL} - segment obtained successfully@*
@code{@value{RPREFIX}INVALID_ADDRESS} - @code{segment} is NULL@*
@code{@value{RPREFIX}INVALID_ADDRESS} - @code{old_size} is NULL@*
@code{@value{RPREFIX}INVALID_ID} - invalid region id@*
@code{@value{RPREFIX}INVALID_ADDRESS} - segment address not in region
@code{@value{RPREFIX}UNSATISFIED} - unable to make segment larger
@subheading DESCRIPTION:
This directive is used to increase or decrease the size of
a @a{segment}. When increasing the size of a segment, it
is possible that there is not memory available contiguous
to the segment. In this case, the request is unsatisfied.
@subheading NOTES:
If an attempt to increase the size of a @a{segment} fails, then
the application may want to allocate a new segment of the desired
size, copy the contents of the original segment to the new, larger
segment and then return the original segment.