IOBufferMemoryDescriptor.h
1 /* 2 * Copyright (c) 1998-2016 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 #ifndef _IOBUFFERMEMORYDESCRIPTOR_H 29 #define _IOBUFFERMEMORYDESCRIPTOR_H 30 31 #include <libkern/c++/OSPtr.h> 32 #include <IOKit/IOMemoryDescriptor.h> 33 #include <DriverKit/IOBufferMemoryDescriptor.h> 34 35 enum { 36 kIOMemoryPhysicallyContiguous = 0x00000010, 37 kIOMemoryPageable = 0x00000020, 38 kIOMemoryPurgeable = 0x00000040, 39 kIOMemoryHostPhysicallyContiguous = 0x00000080, 40 kIOMemorySharingTypeMask = 0x000f0000, 41 kIOMemoryUnshared = 0x00000000, 42 kIOMemoryKernelUserShared = 0x00010000, 43 // shared IOMemoryDescriptor options for IOBufferMemoryDescriptor: 44 kIOBufferDescriptorMemoryFlags = kIOMemoryDirectionMask 45 #ifdef XNU_KERNEL_PRIVATE 46 | kIOMemoryAutoPrepare 47 #endif 48 | kIOMemoryThreadSafe 49 | kIOMemoryClearEncrypt 50 | kIOMemoryMapperNone 51 | kIOMemoryUseReserve 52 }; 53 54 #define _IOBUFFERMEMORYDESCRIPTOR_INTASKWITHOPTIONS_ 1 55 #define _IOBUFFERMEMORYDESCRIPTOR_HOSTPHYSICALLYCONTIGUOUS_ 1 56 #define IOBUFFERMEMORYDESCRIPTOR_SUPPORTS_INTASKWITHOPTIONS_TAGS 1 57 /*! 58 * @class IOBufferMemoryDescriptor 59 * @abstract Provides a simple memory descriptor that allocates its own buffer memory. 60 */ 61 62 class IOBufferMemoryDescriptor : public IOGeneralMemoryDescriptor 63 { 64 OSDeclareDefaultStructorsWithDispatch(IOBufferMemoryDescriptor); 65 66 private: 67 /*! @struct ExpansionData 68 * @discussion This structure will be used to expand the capablilties of this class in the future. 69 */ 70 struct ExpansionData { 71 IOMemoryMap * map; 72 }; 73 74 /*! @var reserved 75 * Reserved for future use. (Internal use only) */ 76 APPLE_KEXT_WSHADOW_PUSH; 77 ExpansionData * reserved; 78 79 protected: 80 void * _buffer; 81 vm_size_t _capacity; 82 vm_offset_t _alignment; 83 IOOptionBits _options; 84 private: 85 uintptr_t _internalReserved; 86 unsigned _internalFlags; 87 APPLE_KEXT_WSHADOW_POP; 88 89 private: 90 #ifndef __LP64__ 91 virtual bool initWithOptions( 92 IOOptionBits options, 93 vm_size_t capacity, 94 vm_offset_t alignment, 95 task_t inTask) APPLE_KEXT_DEPRECATED; /* use withOptions() instead */ 96 #endif /* !__LP64__ */ 97 98 public: 99 virtual bool initWithPhysicalMask( 100 task_t inTask, 101 IOOptionBits options, 102 mach_vm_size_t capacity, 103 mach_vm_address_t alignment, 104 mach_vm_address_t physicalMask); 105 106 #ifdef __LP64__ 107 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 0); 108 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 1); 109 #else /* !__LP64__ */ 110 OSMetaClassDeclareReservedUsedX86(IOBufferMemoryDescriptor, 0); 111 OSMetaClassDeclareReservedUsedX86(IOBufferMemoryDescriptor, 1); 112 #endif /* !__LP64__ */ 113 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 2); 114 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 3); 115 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 4); 116 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 5); 117 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 6); 118 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 7); 119 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 8); 120 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 9); 121 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 10); 122 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 11); 123 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 12); 124 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 13); 125 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 14); 126 OSMetaClassDeclareReservedUnused(IOBufferMemoryDescriptor, 15); 127 128 protected: 129 virtual void free() APPLE_KEXT_OVERRIDE; 130 131 public: 132 133 /* 134 * withOptions: 135 * 136 * Returns a new IOBufferMemoryDescriptor with a buffer large enough to 137 * hold capacity bytes. The descriptor's length is initially set to the 138 * capacity. 139 */ 140 #ifndef __LP64__ 141 virtual bool initWithOptions( IOOptionBits options, 142 vm_size_t capacity, 143 vm_offset_t alignment) APPLE_KEXT_DEPRECATED; /* use withOptions() instead */ 144 #endif /* !__LP64__ */ 145 146 static OSPtr<IOBufferMemoryDescriptor> withCopy( 147 task_t inTask, 148 IOOptionBits options, 149 vm_map_t sourceMap, 150 mach_vm_address_t source, 151 mach_vm_size_t size); 152 153 static OSPtr<IOBufferMemoryDescriptor> withOptions( IOOptionBits options, 154 vm_size_t capacity, 155 vm_offset_t alignment = 1); 156 157 /*! @function inTaskWithOptions 158 * @abstract Creates a memory buffer with memory descriptor for that buffer. 159 * @discussion Added in Mac OS X 10.2, this method allocates a memory buffer with a given size and alignment in the task's address space specified, and returns a memory descriptor instance representing the memory. It is recommended that memory allocated for I/O or sharing via mapping be created via IOBufferMemoryDescriptor. Options passed with the request specify the kind of memory to be allocated - pageablity and sharing are specified with option bits. This function may block and so should not be called from interrupt level or while a simple lock is held. 160 * @param inTask The task the buffer will be allocated in. 161 * @param options Options for the allocation:<br> 162 * kIODirectionOut, kIODirectionIn - set the direction of the I/O transfer.<br> 163 * kIOMemoryPhysicallyContiguous - pass to request memory be physically contiguous. This option is heavily discouraged. The request may fail if memory is fragmented, may cause large amounts of paging activity, and may take a very long time to execute.<br> 164 * kIOMemoryPageable - pass to request memory be non-wired - the default for kernel allocated memory is wired.<br> 165 * kIOMemoryPurgeable - pass to request memory that may later have its purgeable state set with IOMemoryDescriptor::setPurgeable. Only supported for kIOMemoryPageable allocations.<br> 166 * kIOMemoryKernelUserShared - pass to request memory that will be mapped into both the kernel and client applications.<br> 167 * kIOMapInhibitCache - allocate memory with inhibited cache setting. <br> 168 * kIOMapWriteThruCache - allocate memory with writethru cache setting. <br> 169 * kIOMapCopybackCache - allocate memory with copyback cache setting. <br> 170 * kIOMapWriteCombineCache - allocate memory with writecombined cache setting. 171 * @param capacity The number of bytes to allocate. 172 * @param alignment The minimum required alignment of the buffer in bytes - 1 is the default for no required alignment. For example, pass 256 to get memory allocated at an address with bits 0-7 zero. 173 * @result Returns an instance of class IOBufferMemoryDescriptor to be released by the caller, which will free the memory desriptor and associated buffer. */ 174 175 static OSPtr<IOBufferMemoryDescriptor> inTaskWithOptions( 176 task_t inTask, 177 IOOptionBits options, 178 vm_size_t capacity, 179 vm_offset_t alignment = 1); 180 181 /*! @function inTaskWithOptions 182 * @abstract Creates a memory buffer with memory descriptor for that buffer. 183 * @discussion Added in Mac OS X 10.2, this method allocates a memory buffer with a given size and alignment in the task's address space specified, and returns a memory descriptor instance representing the memory. It is recommended that memory allocated for I/O or sharing via mapping be created via IOBufferMemoryDescriptor. Options passed with the request specify the kind of memory to be allocated - pageablity and sharing are specified with option bits. This function may block and so should not be called from interrupt level or while a simple lock is held. 184 * @param inTask The task the buffer will be allocated in. 185 * @param options Options for the allocation:<br> 186 * kIODirectionOut, kIODirectionIn - set the direction of the I/O transfer.<br> 187 * kIOMemoryPhysicallyContiguous - pass to request memory be physically contiguous. This option is heavily discouraged. The request may fail if memory is fragmented, may cause large amounts of paging activity, and may take a very long time to execute.<br> 188 * kIOMemoryPageable - pass to request memory be non-wired - the default for kernel allocated memory is wired.<br> 189 * kIOMemoryPurgeable - pass to request memory that may later have its purgeable state set with IOMemoryDescriptor::setPurgeable. Only supported for kIOMemoryPageable allocations.<br> 190 * kIOMemoryKernelUserShared - pass to request memory that will be mapped into both the kernel and client applications.<br> 191 * kIOMapInhibitCache - allocate memory with inhibited cache setting. <br> 192 * kIOMapWriteThruCache - allocate memory with writethru cache setting. <br> 193 * kIOMapCopybackCache - allocate memory with copyback cache setting. <br> 194 * kIOMapWriteCombineCache - allocate memory with writecombined cache setting. 195 * @param capacity The number of bytes to allocate. 196 * @param alignment The minimum required alignment of the buffer in bytes - 1 is the default for no required alignment. For example, pass 256 to get memory allocated at an address with bits 0-7 zero. 197 * @param kernTag The kernel memory tag 198 * @param userTag The user memory tag 199 * @result Returns an instance of class IOBufferMemoryDescriptor to be released by the caller, which will free the memory desriptor and associated buffer. */ 200 201 static OSPtr<IOBufferMemoryDescriptor> inTaskWithOptions( 202 task_t inTask, 203 IOOptionBits options, 204 vm_size_t capacity, 205 vm_offset_t alignment, 206 uint32_t kernTag, 207 uint32_t userTag); 208 209 /*! @function inTaskWithPhysicalMask 210 * @abstract Creates a memory buffer with memory descriptor for that buffer. 211 * @discussion Added in Mac OS X 10.5, this method allocates a memory buffer with a given size and alignment in the task's address space specified, and returns a memory descriptor instance representing the memory. It is recommended that memory allocated for I/O or sharing via mapping be created via IOBufferMemoryDescriptor. Options passed with the request specify the kind of memory to be allocated - pageablity and sharing are specified with option bits. This function may block and so should not be called from interrupt level or while a simple lock is held. 212 * @param inTask The task the buffer will be mapped in. Pass NULL to create memory unmapped in any task (eg. for use as a DMA buffer). 213 * @param options Options for the allocation:<br> 214 * kIODirectionOut, kIODirectionIn - set the direction of the I/O transfer.<br> 215 * kIOMemoryPhysicallyContiguous - pass to request memory be physically contiguous. This option is heavily discouraged. The request may fail if memory is fragmented, may cause large amounts of paging activity, and may take a very long time to execute.<br> 216 * kIOMemoryKernelUserShared - pass to request memory that will be mapped into both the kernel and client applications.<br> 217 * kIOMapInhibitCache - allocate memory with inhibited cache setting. <br> 218 * kIOMapWriteThruCache - allocate memory with writethru cache setting. <br> 219 * kIOMapCopybackCache - allocate memory with copyback cache setting. <br> 220 * kIOMapWriteCombineCache - allocate memory with writecombined cache setting. 221 * @param capacity The number of bytes to allocate. 222 * @param physicalMask The buffer will be allocated with pages such that physical addresses will only have bits set present in physicalMask. For example, pass 0x00000000FFFFFFFFULL for a buffer to be accessed by hardware that has 32 address bits. 223 * @result Returns an instance of class IOBufferMemoryDescriptor to be released by the caller, which will free the memory desriptor and associated buffer. */ 224 225 static OSPtr<IOBufferMemoryDescriptor> inTaskWithPhysicalMask( 226 task_t inTask, 227 IOOptionBits options, 228 mach_vm_size_t capacity, 229 mach_vm_address_t physicalMask); 230 231 /* 232 * withCapacity: 233 * 234 * Returns a new IOBufferMemoryDescriptor with a buffer large enough to 235 * hold capacity bytes. The descriptor's length is initially set to the 236 * capacity. 237 */ 238 static OSPtr<IOBufferMemoryDescriptor> withCapacity( 239 vm_size_t capacity, 240 IODirection withDirection, 241 bool withContiguousMemory = false); 242 #ifndef __LP64__ 243 virtual bool initWithBytes(const void * bytes, 244 vm_size_t withLength, 245 IODirection withDirection, 246 bool withContiguousMemory = false) APPLE_KEXT_DEPRECATED; /* use withBytes() instead */ 247 #endif /* !__LP64__ */ 248 249 /* 250 * withBytes: 251 * 252 * Returns a new IOBufferMemoryDescriptor preloaded with bytes (copied). 253 * The descriptor's length and capacity are set to the input buffer's size. 254 */ 255 static OSPtr<IOBufferMemoryDescriptor> withBytes( 256 const void * bytes, 257 vm_size_t withLength, 258 IODirection withDirection, 259 bool withContiguousMemory = false); 260 261 /* 262 * setLength: 263 * 264 * Change the buffer length of the memory descriptor. When a new buffer 265 * is created, the initial length of the buffer is set to be the same as 266 * the capacity. The length can be adjusted via setLength for a shorter 267 * transfer (there is no need to create more buffer descriptors when you 268 * can reuse an existing one, even for different transfer sizes). Note 269 * that the specified length must not exceed the capacity of the buffer. 270 */ 271 virtual void setLength(vm_size_t length); 272 273 /* 274 * setDirection: 275 * 276 * Change the direction of the transfer. This method allows one to redirect 277 * the descriptor's transfer direction. This eliminates the need to destroy 278 * and create new buffers when different transfer directions are needed. 279 */ 280 virtual void setDirection(IODirection direction); 281 282 /* 283 * getCapacity: 284 * 285 * Get the buffer capacity 286 */ 287 virtual vm_size_t getCapacity() const; 288 289 /* 290 * getBytesNoCopy: 291 * 292 * Return the virtual address of the beginning of the buffer 293 */ 294 virtual void *getBytesNoCopy(); 295 296 /* 297 * getBytesNoCopy: 298 * 299 * Return the virtual address of an offset from the beginning of the buffer 300 */ 301 virtual void *getBytesNoCopy(vm_size_t start, vm_size_t withLength); 302 303 /* 304 * appendBytes: 305 * 306 * Add some data to the end of the buffer. This method automatically 307 * maintains the memory descriptor buffer length. Note that appendBytes 308 * will not copy past the end of the memory descriptor's current capacity. 309 */ 310 virtual bool appendBytes(const void *bytes, vm_size_t withLength); 311 312 #ifndef __LP64__ 313 virtual void * getVirtualSegment(IOByteCount offset, 314 IOByteCount * length) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED; /* use getBytesNoCopy() instead */ 315 #endif /* !__LP64__ */ 316 }; 317 318 #endif /* !_IOBUFFERMEMORYDESCRIPTOR_H */