os/kernelhwsrv/kernel/eka/memmodel/epoc/flexible/mmu/maddressspace.h
changeset 0 bde4ae8d615e
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/os/kernelhwsrv/kernel/eka/memmodel/epoc/flexible/mmu/maddressspace.h	Fri Jun 15 03:10:57 2012 +0200
     1.3 @@ -0,0 +1,311 @@
     1.4 +// Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.5 +// All rights reserved.
     1.6 +// This component and the accompanying materials are made available
     1.7 +// under the terms of the License "Eclipse Public License v1.0"
     1.8 +// which accompanies this distribution, and is available
     1.9 +// at the URL "http://www.eclipse.org/legal/epl-v10.html".
    1.10 +//
    1.11 +// Initial Contributors:
    1.12 +// Nokia Corporation - initial contribution.
    1.13 +//
    1.14 +// Contributors:
    1.15 +//
    1.16 +// Description:
    1.17 +//
    1.18 +
    1.19 +/**
    1.20 +@file
    1.21 +@internalComponent
    1.22 +*/
    1.23 +
    1.24 +#ifndef MADDRESSSPACE_H
    1.25 +#define MADDRESSSPACE_H
    1.26 +
    1.27 +#include "mrefcntobj.h"
    1.28 +#include "maddrcont.h"
    1.29 +#include "mvalloc.h"
    1.30 +
    1.31 +
    1.32 +
    1.33 +//
    1.34 +// DAddressSpace
    1.35 +//
    1.36 +
    1.37 +/**
    1.38 +Class representing the virtual address space used by a single process.
    1.39 +
    1.40 +Each address space has:
    1.41 +- An MMU page directory.
    1.42 +- An allocator for virtual addresses.
    1.43 +- A list of memory mappings currently mapped into it.
    1.44 +
    1.45 +Most other APIs in the kernel which make use of address spaces don't use pointers to
    1.46 +the address space object itself, instead they use an OS Address Space ID (OS ASID).
    1.47 +This is an integer less than KNumOsAsids and can be used to index into the array of
    1.48 +address space objects - #AddressSpace.
    1.49 +*/
    1.50 +class DAddressSpace : public DReferenceCountedObject
    1.51 +	{
    1.52 +public:
    1.53 +	/**
    1.54 +	Initialiser called during stage 2 of system boot.
    1.55 +	This includes initialisation of the kernel's address space object.
    1.56 +	*/
    1.57 +	static void Init2();
    1.58 +
    1.59 +	/**
    1.60 +	Create a new address space.
    1.61 +
    1.62 +	This creates a DAddressSpace address space object and adds it to the array
    1.63 +	of all address space objects - #AddressSpace. The function returns the objects
    1.64 +	index into this array, this value is used as OS Address Space ID (OS ASID)
    1.65 +	in most kernel APIs which refer to address spaces.
    1.66 +
    1.67 +	@param[out] aPageDirectory	Returns the physical address of the MMU page directory
    1.68 +								which was created for the new address space.
    1.69 +
    1.70 +	@return On success, the OS ASID value for the new address space;
    1.71 +			otherwise one of the system wide error codes
    1.72 +	*/
    1.73 +	static TInt New(TPhysAddr& aPageDirectory);
    1.74 +public:
    1.75 +	DAddressSpace();
    1.76 +	~DAddressSpace();
    1.77 +
    1.78 +	/**
    1.79 +	Allocate a region of virtual addresses within this address space.
    1.80 +
    1.81 +	The returned region may have a start address and/or size which is different to
    1.82 +	those requested due to various alignment requirements in the implementation.
    1.83 +	However the returned region will always include all addresses requested.
    1.84 +
    1.85 +	The range of virtual addresses available to a user-side address space is
    1.86 +	#KUserLocalDataBase through to #KUserLocalDataEnd.
    1.87 +
    1.88 +	The range of virtual addresses available to the kernel's address space (#KKernelOsAsid)
    1.89 +	is #KKernelSectionBase though to #KKernelSectionEnd.
    1.90 +
    1.91 +	@param[out] aAddr			Returns the start address of the region which was allocated.
    1.92 +								This will always be aligned to a multiple of the page colouring
    1.93 +								size: #KPageColourCount*#KPageSize.
    1.94 +	@param[out] aSize			Returns the size, in bytes, of the region which was allocated.
    1.95 +	@param		aRequestedAddr	The requested start address of the region to allocate,
    1.96 +								or zero if no specific address is required.
    1.97 +	@param		aRequestedSize	The requested size, in bytes, of the region to allocate.
    1.98 +	@param		aPdeType		A value from #TPdeType ORed with flags from #TVirtualSlabType.
    1.99 +								This is used to prevent incompatible memory uses (different
   1.100 +								\a aPdeType values) from being allocated virtual addresses
   1.101 +								which would share the same MMU page table.
   1.102 +
   1.103 +	@return KErrNone if successful, otherwise one of the system wide error codes.
   1.104 +	*/
   1.105 +	TInt AllocateVirtualMemory(TLinAddr& aAddr, TUint& aSize, TLinAddr aRequestedAddr, TUint aRequestedSize, TUint aPdeType);
   1.106 +
   1.107 +	/**
   1.108 +	Allocate a region of virtual addresses within the global address region, for use by
   1.109 +	user-side code. These global addresses are outside the range of addresses used
   1.110 +	by any individual address space, and so are globally unique. They lie in the range
   1.111 +	from #KGlobalMemoryBase through to #KUserMemoryLimit.
   1.112 +
   1.113 +	The arguments for this function are of the same type and use as #AllocateVirtualMemory.
   1.114 +	*/
   1.115 +	static TInt AllocateUserGlobalVirtualMemory(TLinAddr& aAddr, TUint& aSize, TLinAddr aRequestedAddr, TUint aRequestedSize, TUint aPdeType);
   1.116 +
   1.117 +	/**
   1.118 +	Free a virtual addresses region which was allocated with #AllocateVirtualMemory
   1.119 +	or #AllocateUserGlobalVirtualMemory. The region supplied to this function
   1.120 +	must either be one supplied to a previous call to AllocateVirtualMemory or
   1.121 +	be one returned by that function.
   1.122 +
   1.123 +	@param aAddr	Start address of the region to be freed.
   1.124 +	@param aSize	Size, in bytes, of the region to be freed.
   1.125 +	*/
   1.126 +	void FreeVirtualMemory(TLinAddr aAddr, TUint aSize);
   1.127 +
   1.128 +	/**
   1.129 +	Allocate a region of virtual addresses for use by memory which should appear at
   1.130 +	the same address in all user-side processes which map it. E.g. for position dependant
   1.131 +	memory like executable code.
   1.132 +
   1.133 +	The region allocated lies in the range used by normal user-side address spaces
   1.134 +	but there is no guarantee that the addresses are not already in use by any of them,
   1.135 +	and there is nothing to prevent the allocated addresses from being returned by any
   1.136 +	future call to #AllocateVirtualMemory.
   1.137 +
   1.138 +	However, as the 'common' addresses are allocated from the top of memory downwards
   1.139 +	and #AllocateVirtualMemory allocates upwards from the bottom of memory it XXX TODO
   1.140 +
   1.141 +	The arguments for this function are of the same type and use as #AllocateVirtualMemory.
   1.142 +	*/
   1.143 +	static TInt AllocateUserCommonVirtualMemory(TLinAddr& aAddr, TUint& aSize, TLinAddr aRequestedAddr, TUint aRequestedSize, TUint aPdeType);
   1.144 +
   1.145 +	/**
   1.146 +	Free a virtual addresses region which was allocated with #AllocateUserCommonVirtualMemory.
   1.147 +	The region supplied to this function must either be one supplied to a previous
   1.148 +	call to AllocateVirtualMemory or be one returned by that function.
   1.149 +
   1.150 +	@param aAddr	Start address of the region to be freed.
   1.151 +	@param aSize	Size, in bytes, of the region to be freed.
   1.152 +	*/
   1.153 +	static void FreeUserCommonVirtualMemory(TLinAddr aAddr, TUint aSize);
   1.154 +
   1.155 +	/**
   1.156 +	Add a memory mapping to this address space's list of mappings.
   1.157 +
   1.158 +	This is intended only for use by #DMemoryMapping.
   1.159 +
   1.160 +	@param aAddr	The address which is allocated to the mapping
   1.161 +					(DMemoryMapping::iAllocatedLinAddrAndOsAsid&~KPageMask).
   1.162 +	@param aMapping	The mapping to add.
   1.163 +
   1.164 +	@return KErrNone if successful, otherwise one of the system wide error codes.
   1.165 +	*/
   1.166 +	TInt AddMapping(TLinAddr aAddr, DMemoryMapping* aMapping);
   1.167 +
   1.168 +	/**
   1.169 +	Remove a memory mapping from this address space's list of mappings.
   1.170 +
   1.171 +	This is intended only for use by #DMemoryMapping.
   1.172 +
   1.173 +	@param aAddr	The address which was used to add the mapping with AddMapping.
   1.174 +
   1.175 +	@return Pointer to the removed mapping or the null pointer if no mapping
   1.176 +			was found to match the specified address.
   1.177 +	*/
   1.178 +	DMemoryMapping* RemoveMapping(TLinAddr aAddr);
   1.179 +
   1.180 +	/**
   1.181 +	Get a pointer to a memory mapping which was previously added to this
   1.182 +	address space's list of mappings. This function does not perform any additional
   1.183 +	reference counting or locking to prevent the returned pointer becoming invalid,
   1.184 +	therefore the caller must ensure that it is not possible for another thread to
   1.185 +	destroy the mapping.
   1.186 +
   1.187 +	The typical use case for this function is where the owner of the mapping has
   1.188 +	not saved the pointer to the mapping object but has instead kept track of the
   1.189 +	virtual address it uses. This function can then be used to retrieve the pointer
   1.190 +	to the object again.
   1.191 +
   1.192 +	If no mapping exists for the specified address the results are unpredictable.
   1.193 +
   1.194 +	@param aAddr	The address which was used to add the mapping with AddMapping.
   1.195 +
   1.196 +	@return Pointer to the mapping.
   1.197 +	*/
   1.198 +	DMemoryMapping* GetMapping(TLinAddr aAddr);
   1.199 +
   1.200 +	/**
   1.201 +	Find the mapping within this address space which maps a specified region of
   1.202 +	addresses. A mapping is only found if all of the bytes in the specified region
   1.203 +	lie within it and it is current mapping a memory object (#DMemoryMapping::IsAttached
   1.204 +	returns true).
   1.205 +
   1.206 +	The returned mapping will have had its reference count incremented and it is
   1.207 +	the callers responsibility to balance this with a #Close or #AsyncClose.
   1.208 +
   1.209 +	@param		aAddr				The start address of the region.
   1.210 +	@param		aSize				The size, in bytes, of the region.
   1.211 +	@param[out] aOffsetInMapping	Returns the byte address offset within the found
   1.212 +									mapping which corresponds to \a aAddr.
   1.213 +	@param[out] aInstanceCount		The instance count of the found mapping.
   1.214 +
   1.215 +	@return Pointer to the mapping which contains the specified region
   1.216 +			or the null pointer if no mapping was found.
   1.217 +
   1.218 +	@post The returned mapping will have had its reference count incremented.
   1.219 +	*/
   1.220 +	DMemoryMapping* FindMapping(TLinAddr aAddr, TUint aSize, TUint& aOffsetInMapping, TUint& aInstanceCount);
   1.221 +
   1.222 +	/**
   1.223 +	Check that the virtual addresses previously allocated with #AllocateVirtualMemory
   1.224 +	or #AllocateUserGlobalVirtualMemory are compatible with the specified 'pde type'.
   1.225 +
   1.226 +	This is only intended for used by error checking in debug builds.
   1.227 +
   1.228 +	@param aAddr	The start address of the region.
   1.229 +	@param aSize	The size, in bytes, of the region.
   1.230 +	@param aPdeType	See description in AllocateVirtualMemory.
   1.231 +	*/
   1.232 +	TBool CheckPdeType(TLinAddr aAddr, TUint aSize, TUint aPdeType);
   1.233 +
   1.234 +private:
   1.235 +	/**
   1.236 +	Second phase constructor.
   1.237 +
   1.238 +	@param aOsAsid	The OS ASID for the address space.
   1.239 +	@param aStart	The first virtual address available in the address space.
   1.240 +	@param aEnd		The last virtual address (plus one) available in the address space.
   1.241 +
   1.242 +	@return KErrNone if successful, otherwise one of the system wide error codes.
   1.243 +	*/
   1.244 +	TInt Construct(TInt aOsAsid, TLinAddr aStart, TLinAddr aEnd);
   1.245 +
   1.246 +	/**
   1.247 +	Wait on the mutex used to protect virtual address allocation and the
   1.248 +	addition/removal of memory mappings. This is only used internally by
   1.249 +	the DAddressSpace methods.
   1.250 +	*/
   1.251 +	void Lock();
   1.252 +
   1.253 +	/**
   1.254 +	Reverse the action of #Lock.
   1.255 +	*/
   1.256 +	void Unlock();
   1.257 +
   1.258 +	/**
   1.259 +	In debug builds, dump information about each mapping in the address to the
   1.260 +	kernel trace port.
   1.261 +	*/
   1.262 +	void Dump();
   1.263 +
   1.264 +private:
   1.265 +	/**
   1.266 +	The OS ASID value for this address space.
   1.267 +	This is its index in the array #AddressSpace.
   1.268 +	*/
   1.269 +	TInt iOsAsid;
   1.270 +
   1.271 +	/**
   1.272 +	Lock currently being used to protect virtual address allocation (#iVirtualAllocator)
   1.273 +	and changes to the mapping container (#iMappings).
   1.274 +	*/
   1.275 +	DMutex* iLock;
   1.276 +
   1.277 +	/**
   1.278 +	Container containing all mappings added to this address space.
   1.279 +	*/
   1.280 +	RAddressedContainer iMappings;
   1.281 +
   1.282 +	/**
   1.283 +	Allocator object for virtual addresses within the address space.
   1.284 +	*/
   1.285 +	RVirtualAllocator iVirtualAllocator;
   1.286 +
   1.287 +private:
   1.288 +	/**
   1.289 +	Allocator for virtual addresses within the global address region for use by user-side code.
   1.290 +
   1.291 +	This is used by #AllocateUserGlobalVirtualMemory and the lock mutex for the
   1.292 +	kernel's address space is used to protect access.
   1.293 +	*/
   1.294 +	static RVirtualAllocator UserGlobalVirtualAllocator;
   1.295 +
   1.296 +	/**
   1.297 +	Allocator for virtual addresses for use by memory which should appear at
   1.298 +	the same address in all user-side processes which map it.
   1.299 +
   1.300 +	This is used by AllocateUserCommonVirtualMemory and the lock mutex for the
   1.301 +	kernel's address space is used to protect access.
   1.302 +	*/
   1.303 +	static RBackwardsVirtualAllocator UserCommonVirtualAllocator;
   1.304 +	};
   1.305 +
   1.306 +
   1.307 +/**
   1.308 +Array of all address spaces. An OS Address Space ID (OS ASID) can be used to
   1.309 +index this array to find the corresponding DAddressSpace object.
   1.310 +*/
   1.311 +extern DAddressSpace* AddressSpace[];
   1.312 +
   1.313 +
   1.314 +#endif