L4Re – L4 Runtime Environment
L4Re::Rm Class Reference

Region map. More...

#include <l4/re/rm>

+ Inheritance diagram for L4Re::Rm:
+ Collaboration diagram for L4Re::Rm:

Data Structures

struct  F
 Rm flags definitions. More...
 
struct  Range
 A range of virtual addresses. More...
 

Public Types

enum  Detach_result { Detached_ds = 0 , Kept_ds = 1 , Split_ds = 2 , Detach_result_mask = 3 , Detach_again = 4 }
 Result values for detach operation. More...
 
enum  Region_flag_shifts { Caching_shift = Dataspace::F::Caching_shift }
 
enum  Detach_flags { Detach_exact = 1 , Detach_overlap = 2 , Detach_keep = 4 }
 Flags for detach operation. More...
 
using Region = Range
 A region is a range of virtual addresses which is backed by a dataspace. More...
 
using Area = Range
 An area is a range of virtual addresses which is reserved, see L4Re::Rm::reserve_area(). More...
 

Public Member Functions

long reserve_area (l4_addr_t *start, unsigned long size, Flags flags=Flags(0), unsigned char align=L4_PAGESHIFT) const noexcept
 Reserve the given area in the region map. More...
 
template<typename T >
long reserve_area (T **start, unsigned long size, Flags flags=Flags(0), unsigned char align=L4_PAGESHIFT) const noexcept
 Reserve the given area in the region map. More...
 
long free_area (l4_addr_t addr)
 Free an area from the region map. More...
 
long attach (l4_addr_t *start, unsigned long size, Flags flags, L4::Ipc::Cap< Dataspace > mem, Offset offs=0, unsigned char align=L4_PAGESHIFT) const noexcept
 Attach a data space to a region. More...
 
template<typename T >
long attach (T **start, unsigned long size, Flags flags, L4::Ipc::Cap< Dataspace > mem, Offset offs=0, unsigned char align=L4_PAGESHIFT) const noexcept
 Attach a data space to a region. More...
 
int detach (l4_addr_t addr, L4::Cap< Dataspace > *mem, L4::Cap< L4::Task > const &task=This_task) const noexcept
 Detach a region from the address space. More...
 
int detach (void *addr, L4::Cap< Dataspace > *mem, L4::Cap< L4::Task > const &task=This_task) const noexcept
 Detach a region from the address space. More...
 
int detach (l4_addr_t start, unsigned long size, L4::Cap< Dataspace > *mem, L4::Cap< L4::Task > const &task) const noexcept
 Detach all regions of the specified interval. More...
 
int find (l4_addr_t *addr, unsigned long *size, Offset *offset, L4Re::Rm::Flags *flags, L4::Cap< Dataspace > *m) noexcept
 Find a region given an address and size. More...
 
long get_regions (l4_addr_t start, L4::Ipc::Ret_array< Range > regions)
 Return the list of regions whose starting addresses are higher or equal to start in the address space managed by this region map. More...
 
long get_areas (l4_addr_t start, L4::Ipc::Ret_array< Range > areas)
 Return the list of areas whose starting addresses are higher or equal to start in the address space managed by this region map. More...
 
- Public Member Functions inherited from L4::Pager
l4_msgtag_t page_fault (l4_umword_t pfa, l4_umword_t pc, L4::Ipc::Rcv_fpage rwin, L4::Ipc::Opt< L4::Ipc::Snd_fpage & > fp)
 Page-fault protocol message. More...
 
- Public Member Functions inherited from L4::Io_pager
l4_msgtag_t io_page_fault (l4_fpage_t io_pfa, l4_umword_t pc, L4::Ipc::Rcv_fpage rwin, L4::Ipc::Opt< L4::Ipc::Snd_fpage & > fp)
 IO page fault protocol message. More...
 

Additional Inherited Members

- Protected Types inherited from L4::Kobject_t< Rm, L4::Pager, L4RE_PROTO_RM, L4::Type_info::Demand_t< 1 > >
typedef Rm Class
 The target interface type (inheriting from Kobject_t)
 
typedef Typeid::Iface< PROTO, Rm > __Iface
 The interface description for the derived class.
 
typedef Typeid::Merge_list< Typeid::Iface_list< __Iface >, typename Base::__Iface_list > __Iface_list
 The list of all RPC interfaces provided directly or through inheritance.
 
- Protected Types inherited from L4::Kobject_t< Pager, Io_pager, L4_PROTO_PAGE_FAULT >
typedef Pager Class
 The target interface type (inheriting from Kobject_t)
 
typedef Typeid::Iface< PROTO, Pager__Iface
 The interface description for the derived class.
 
typedef Typeid::Merge_list< Typeid::Iface_list< __Iface >, typename Base::__Iface_list > __Iface_list
 The list of all RPC interfaces provided directly or through inheritance.
 
- Protected Member Functions inherited from L4::Kobject_t< Rm, L4::Pager, L4RE_PROTO_RM, L4::Type_info::Demand_t< 1 > >
L4::Cap< Classc () const noexcept
 Get the capability to ourselves.
 
- Protected Member Functions inherited from L4::Kobject_t< Pager, Io_pager, L4_PROTO_PAGE_FAULT >
L4::Cap< Classc () const noexcept
 Get the capability to ourselves.
 
- Static Protected Member Functions inherited from L4::Kobject_t< Rm, L4::Pager, L4RE_PROTO_RM, L4::Type_info::Demand_t< 1 > >
static void __check_protocols__ () noexcept
 Helper to check for protocol conflicts.
 
- Static Protected Member Functions inherited from L4::Kobject_t< Pager, Io_pager, L4_PROTO_PAGE_FAULT >
static void __check_protocols__ () noexcept
 Helper to check for protocol conflicts.
 

Detailed Description

Region map.

See also
Region map API .

Definition at line 73 of file rm.

Member Typedef Documentation

◆ Area

An area is a range of virtual addresses which is reserved, see L4Re::Rm::reserve_area().

See also
Region map API

Definition at line 592 of file rm.

◆ Region

A region is a range of virtual addresses which is backed by a dataspace.

See also
Region map API

Definition at line 584 of file rm.

Member Enumeration Documentation

◆ Detach_flags

Flags for detach operation.

Enumerator
Detach_exact 

Do an unmap of the exact region given.

Detach_overlap 

Do an unmap of all overlapping regions.

Detach_keep 

Do not free the detached data space, ignore the F::Detach_free.

Definition at line 200 of file rm.

◆ Detach_result

Result values for detach operation.

Enumerator
Detached_ds 

Detached data sapce.

Kept_ds 

Kept data space.

Split_ds 

Splitted data space, and done.

Detach_again 

Detached data space, more to do.

Definition at line 81 of file rm.

◆ Region_flag_shifts

Enumerator
Caching_shift 

Start of Rm cache bits.

Definition at line 92 of file rm.

Member Function Documentation

◆ attach() [1/2]

long L4Re::Rm::attach ( l4_addr_t start,
unsigned long  size,
Rm::Flags  flags,
L4::Ipc::Cap< Dataspace mem,
Rm::Offset  offs = 0,
unsigned char  align = L4_PAGESHIFT 
) const
noexcept

Attach a data space to a region.

Parameters
[in,out]startVirtual start address where the region manager shall attach the data space. If L4Re::Rm::F::Search_addr is given this value is used as the start address to search for a free virtual memory region and the resulting address is returned here. If L4Re::Rm::F::In_area is given the value is used as a selector for the area (see L4Re::Rm::reserve_area) to attach the data space to.
sizeSize of the data space to attach (in bytes)
flagsThe flags control how and with which rights the dataspace is attached to the region. See L4Re::Rm::F::Attach_flags and L4Re::Rm::F::Region_flags. The caller must specify the desired rights of the attached region explicitly. The default set of rights is empty. If the F::Eager_map flag is set this function may also return L4Re::Dataspace::map error codes if the mapping fails.
memData space
offsOffset into the data space to use
alignAlignment of the virtual region, log2-size, default: a page (L4_PAGESHIFT). This is only meaningful if the L4Re::Rm::F::Search_addr flag is used.
Return values
0Success
-L4_ENOENTNo area could be found (see L4Re::Rm::F::In_area)
-L4_EPERMOperation not allowed.
-L4_EINVAL
-L4_EADDRNOTAVAILThe given address is not available.
<0IPC errors

Makes the whole or parts of a data space visible in the virtual memory of the corresponding task. The corresponding region in the virtual address space is backed with the contents of the dataspace.

Note
When searching for a free place in the virtual address space, the space between start and the end of the virtual address space is searched.
There is no region object created, instead the region is defined by a virtual address within this range (see L4Re::Rm::find).

Definition at line 43 of file rm_impl.h.

◆ attach() [2/2]

template<typename T >
long L4Re::Rm::attach ( T **  start,
unsigned long  size,
Flags  flags,
L4::Ipc::Cap< Dataspace mem,
Offset  offs = 0,
unsigned char  align = L4_PAGESHIFT 
) const
inlinenoexcept

Attach a data space to a region.

Parameters
[in,out]startVirtual start address where the region manager shall attach the data space. If L4Re::Rm::F::Search_addr is given this value is used as the start address to search for a free virtual memory region and the resulting address is returned here. If L4Re::Rm::F::In_area is given the value is used as a selector for the area (see L4Re::Rm::reserve_area) to attach the data space to.
sizeSize of the data space to attach (in bytes)
flagsThe flags control how and with which rights the dataspace is attached to the region. See L4Re::Rm::F::Attach_flags and L4Re::Rm::F::Region_flags. The caller must specify the desired rights of the attached region explicitly. The default set of rights is empty. If the F::Eager_map flag is set this function may also return L4Re::Dataspace::map error codes if the mapping fails.
memData space
offsOffset into the data space to use
alignAlignment of the virtual region, log2-size, default: a page (L4_PAGESHIFT). This is only meaningful if the L4Re::Rm::F::Search_addr flag is used.
Return values
0Success
-L4_ENOENTNo area could be found (see L4Re::Rm::F::In_area)
-L4_EPERMOperation not allowed.
-L4_EINVAL
-L4_EADDRNOTAVAILThe given address is not available.
<0IPC errors

Makes the whole or parts of a data space visible in the virtual memory of the corresponding task. The corresponding region in the virtual address space is backed with the contents of the dataspace.

Note
When searching for a free place in the virtual address space, the space between start and the end of the virtual address space is searched.
There is no region object created, instead the region is defined by a virtual address within this range (see L4Re::Rm::find).

Definition at line 369 of file rm.

◆ detach() [1/3]

int L4Re::Rm::detach ( l4_addr_t  addr,
L4::Cap< Dataspace > *  mem,
L4::Cap< L4::Task > const &  task = This_task 
) const
inlinenoexcept

Detach a region from the address space.

Parameters
addrVirtual address of region, any address within the region is valid.
[out]memDataspace that is affected. Give 0 if not interested.
taskThis argument specifies the task where the pages are unmapped. Provide L4::Cap<L4::Task>::Invalid for none. The default is the current task.
Return values
Detach_resultOn success.
-L4_ENOENTNo region found.
<0IPC errors

Frees a region in the virtual address space given by addr (address type). The corresponding part of the address space is now available again.

Definition at line 637 of file rm.

◆ detach() [2/3]

int L4Re::Rm::detach ( l4_addr_t  start,
unsigned long  size,
L4::Cap< Dataspace > *  mem,
L4::Cap< L4::Task > const &  task 
) const
inlinenoexcept

Detach all regions of the specified interval.

Parameters
startStart of area to detach, must be within region.
sizeSize of of area to detach (in bytes).
[out]memDataspace that is affected. Give 0 if not interested.
taskThis argument specifies the task where the pages are unmapped. Provide L4::Cap<L4::Task>::Invalid for none. The default is the current task.
Return values
Detach_resultOn success.
-L4_ENOENTNo region found.
<0IPC errors

Frees all regions within the interval given by start and size. If a region overlaps the start or the end of the interval this region is only detached partly. If the interval is within one region the original region is split up into two separate regions.

Definition at line 647 of file rm.

◆ detach() [3/3]

int L4Re::Rm::detach ( void *  addr,
L4::Cap< Dataspace > *  mem,
L4::Cap< L4::Task > const &  task = This_task 
) const
inlinenoexcept

Detach a region from the address space.

Parameters
addrVirtual address of region, any address within the region is valid.
[out]memDataspace that is affected. Give 0 if not interested.
taskThis argument specifies the task where the pages are unmapped. Provide L4::Cap<L4::Task>::Invalid for none. The default is the current task.
Return values
Detach_resultOn success.
-L4_ENOENTNo region found.
<0IPC errors

Frees a region in the virtual address space given by addr (address type). The corresponding part of the address space is now available again.

Definition at line 642 of file rm.

◆ find()

int L4Re::Rm::find ( l4_addr_t addr,
unsigned long *  size,
Offset *  offset,
L4Re::Rm::Flags *  flags,
L4::Cap< Dataspace > *  m 
)
inlinenoexcept

Find a region given an address and size.

Parameters
[in,out]addrAddress to look for. Returns the start address of the found region.
[in,out]sizeSize of the area to look for (in bytes). Returns the size of the found region (in bytes).
[out]offsetOffset at the beginning of the region within the associated dataspace.
[out]flagsRegion flags, see F::Region_flags (and F::In_area).
[out]mAssociated dataspace or paging service.
Return values
0Success
-L4_EPERMOperation not allowed.
-L4_ENOENTNo region found.
<0IPC errors

This function returns the properties of the region that contains the area described by the addr and size parameter. If no such region is found but a reserved area, the area is returned and F::In_area is set in `flags`. Note, in the case of an area the `offset` and `m` return values are invalid.

                size-out
              /           \
             /             \
         addr-out           \
            ^________________\
------------|----------------|------------------
|           | Region         |       Dataspace |
|           |_______|___|____|                 |
------------|-------|---|-----------------------
 \         /        |\ /
  \       /         | |> size-in
  offset-out        |
                    |> addr-in
Note
The value of the size input parameter should be 1 to assure that a region can be determined unambiguously.

Definition at line 559 of file rm.

◆ free_area()

long L4Re::Rm::free_area ( l4_addr_t  addr)

Free an area from the region map.

Parameters
addrAn address within the area to free.
Return values
0Success
-L4_ENOENTNo area found.
<0IPC errors
Note
The data spaces that are attached to that area are not detached by this operation.
See also
reserve_area() for more information about areas.

◆ get_areas()

long L4Re::Rm::get_areas ( l4_addr_t  start,
L4::Ipc::Ret_array< Range areas 
)

Return the list of areas whose starting addresses are higher or equal to start in the address space managed by this region map.

Parameters
startVirtual address from where to start searching.
[out]areasList of areas found in this region map.
Return values
>=0Number of returned areas in the areas array.
<0IPC errors
Note
The returned list of areas might not be complete and the caller shall use the function repeatedly with a start address one larger than the end address of the last area from the previous call.

◆ get_regions()

long L4Re::Rm::get_regions ( l4_addr_t  start,
L4::Ipc::Ret_array< Range regions 
)

Return the list of regions whose starting addresses are higher or equal to start in the address space managed by this region map.

Parameters
startVirtual address from where to start searching.
[out]regionsList of regions found in this region map.
Return values
>=0Number of returned regions in the regions array.
<0IPC errors
Note
The returned list of regions might not be complete and the caller shall use the function repeatedly with a start address one larger that the end address of the last region from the previous call.

◆ reserve_area() [1/2]

long L4Re::Rm::reserve_area ( l4_addr_t start,
unsigned long  size,
Flags  flags = Flags(0),
unsigned char  align = L4_PAGESHIFT 
) const
inlinenoexcept

Reserve the given area in the region map.

Parameters
[in,out]startThe virtual start address of the area to reserve. Returns the start address of the area.
sizeThe size of the area to reserve (in bytes).
flagsFlags for the reserved area (see L4Re::Rm::F::Region_flags and L4Re::Rm::F::Attach_flags).
alignAlignment of area if searched as bits (log2 value).
Return values
0Success
-L4_EADDRNOTAVAILThe given area cannot be reserved.
<0IPC errors

This function reserves an area within the virtual address space implemented by the region map. There are two kinds of areas available:

  • Reserved areas (flags = F::Reserved), where no data spaces can be attached
  • Special purpose areas (flags = 0), where data spaces can be attached to the area via the F::In_area flag and a start address within the area itself.
Note
When searching for a free place in the virtual address space (with flags = F::Search_addr), the space between start and the end of the virtual address space is searched.

Definition at line 258 of file rm.

◆ reserve_area() [2/2]

template<typename T >
long L4Re::Rm::reserve_area ( T **  start,
unsigned long  size,
Flags  flags = Flags(0),
unsigned char  align = L4_PAGESHIFT 
) const
inlinenoexcept

Reserve the given area in the region map.

Parameters
[in,out]startThe virtual start address of the area to reserve. Returns the start address of the area.
sizeThe size of the area to reserve (in bytes).
flagsFlags for the reserved area (see F::Region_flags and F::Attach_flags).
alignAlignment of area if searched as bits (log2 value).
Return values
0Success
-L4_EADDRNOTAVAILThe given area cannot be reserved.
<0IPC errors

For more information, please refer to the analogous function

See also
L4Re::Rm::reserve_area.

Definition at line 284 of file rm.


The documentation for this class was generated from the following files: