iokit/DriverKit/IOMemoryDescriptor.iig

   1 /*
   2  * Copyright (c) 2019-2019 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #if !__IIG
  30 #if KERNEL
  31 #include <IOKit/IOMemoryDescriptor.h>
  32 #endif
  33 #endif
  34
  35 #ifndef _IOKIT_UIOMEMORYDESCRIPTOR_H
  36 #define _IOKIT_UIOMEMORYDESCRIPTOR_H
  37
  38 #include <DriverKit/OSObject.iig>
  39
  40 class IOService;
  41 class IOMemoryMap;
  42
  43
  44 // IOMemoryDescriptor Create options
  45 enum {
  46         kIOMemoryDirectionIn    = 0x00000001,
  47         kIOMemoryDirectionOut   = 0x00000002,
  48         kIOMemoryDirectionOutIn = kIOMemoryDirectionIn | kIOMemoryDirectionOut,
  49         kIOMemoryDirectionInOut = kIOMemoryDirectionOutIn,
  50 };
  51
  52 // IOMemoryDescriptor CreateMapping options
  53 enum {
  54         kIOMemoryMapFixedAddress          = 0x00000001,
  55         kIOMemoryMapReadOnly              = 0x00000002,
  56         kIOMemoryMapCacheModeDefault      = 0x00000000,
  57         kIOMemoryMapCacheModeInhibit      = 0x00000100,
  58         kIOMemoryMapCacheModeCopyback     = 0x00000200,
  59         kIOMemoryMapCacheModeWriteThrough = 0x00000400,
  60 };
  61
  62 struct IOAddressSegment {
  63         uint64_t address;
  64         uint64_t length;
  65 };
  66
  67 struct IOMDPrivateState {
  68         uint64_t length;
  69         uint64_t options;
  70 };
  71
  72 /*!
  73  * @class IOMemoryDescriptor
  74  *
  75  * @abstract
  76  * IOMemoryDescriptor describes a memory buffer.
  77  *
  78  * @discussion
  79  * To allocate memory for I/O or sharing, use IOBufferMemoryDescriptor::Create()
  80  * Methods in this class are used for memory that was supplied as a parameter.
  81  *
  82
  83 @iig implementation
  84 #include <DriverKit/IOService.h>
  85 @iig end
  86 */
  87
  88 class KERNEL IOMemoryDescriptor : public OSObject
  89 {
  90 public:
  91
  92
  93         virtual bool
  94         init() override;
  95
  96         virtual void
  97         free() override;
  98
  99     /*!
 100      * @brief       Obtain the length of the memory described.
 101      * @param       returnLength Returned length.
 102      * @return      kIOReturnSuccess on success. See IOReturn.h for error codes.
 103      */
 104         kern_return_t
 105         GetLength(
 106                 uint64_t * returnLength) LOCALONLY;
 107
 108     /*!
 109      * @brief       Create a mapping of the memory in the callers address space.
 110      * @param       options
 111          *              kIOMemoryMapFixedAddress map at the address requested
 112          *              kIOMemoryMapReadOnly create a read only mapping
 113          *              kIOMemoryMapCacheModeDefault default cache mode
 114          *              kIOMemoryMapCacheModeInhibit inhibited cache mode
 115          *              kIOMemoryMapCacheModeCopyback copyback cache mode
 116          *              kIOMemoryMapCacheModeWriteThrough write through cache mode
 117          * @param       address Requested address if kIOMemoryMapFixedAddress was passed
 118          * @param       offset Start offset of the mapping in the descriptor.
 119          * @param       length Pass zero to map the entire memory, or a value <= the length of the descriptor.
 120          * @param       alignment of the memory virtual mapping. Only zero for no alignment is supported.
 121          * @param       map Returned IOMemoryMap object with +1 retain count.
 122          *              It should be retained until the map is no longer required.
 123      * @return      kIOReturnSuccess on success. See IOReturn.h for error codes.
 124      */
 125         virtual kern_return_t
 126         CreateMapping(
 127                 uint64_t options,
 128                 uint64_t address,
 129                 uint64_t offset,
 130                 uint64_t length,
 131                 uint64_t alignment,
 132                 IOMemoryMap ** map);
 133
 134 private:
 135         virtual kern_return_t
 136         PrepareForDMA(
 137                 uint64_t options,
 138                 IOService * device,
 139                 uint64_t offset,
 140                 uint64_t length,
 141
 142                 uint64_t * flags,
 143                 uint64_t * returnLength,
 144                 uint32_t * segmentsCount,
 145                 IOAddressSegment segments[32]);
 146
 147         kern_return_t
 148         Map(
 149                 uint64_t options,
 150                 uint64_t address,
 151                 uint64_t length,
 152                 uint64_t alignment,
 153
 154                 uint64_t * returnAddress,
 155                 uint64_t * returnLength) LOCALONLY;
 156 };
 157
 158 class EXTENDS (IOMemoryDescriptor) IOMemoryDescriptorPrivate
 159 {
 160         virtual kern_return_t
 161         _CopyState(
 162                 IOMDPrivateState * state);
 163 };
 164
 165
 166
 167 #endif /* ! _IOKIT_UIOMEMORYDESCRIPTOR_H */