iokit/IOKit/IOLib.h

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
  24  *
  25  * HISTORY
  26  *
  27  */
  28
  29 #ifndef __IOKIT_IOLIB_H
  30 #define __IOKIT_IOLIB_H
  31
  32 #ifndef KERNEL
  33 #error IOLib.h is for kernel use only
  34 #endif
  35
  36 #ifndef IOKIT_DEPRECATED
  37 #define IOKIT_DEPRECATED        1
  38 #endif
  39
  40 #include <IOKit/system.h>
  41
  42 #include <IOKit/IOReturn.h>
  43 #include <IOKit/IOTypes.h>
  44 #include <IOKit/IOLocks.h>
  45
  46 #include <libkern/OSAtomic.h>
  47
  48 #ifdef __cplusplus
  49 extern "C" {
  50 #endif
  51
  52 #include <kern/thread_call.h>
  53 #include <kern/clock.h>
  54
  55 /*
  56  * min/max macros.
  57  */
  58
  59 #define min(a,b) ((a) < (b) ? (a) : (b))
  60 #define max(a,b) ((a) > (b) ? (a) : (b))
  61
  62 /*
  63  * These are opaque to the user.
  64  */
  65 typedef thread_t IOThread;
  66 typedef void (*IOThreadFunc)(void *argument);
  67
  68 /*
  69  * Memory allocation functions.
  70  */
  71
  72 /*! @function IOMalloc
  73     @abstract Allocates general purpose, wired memory in the kernel map.
  74     @discussion This is a general purpose utility to allocate memory in the kernel. There are no alignment guarantees given on the returned memory, and alignment may vary depending on the kernel configuration. This function may block and so should not be called from interrupt level or while a simple lock is held.
  75     @param size Size of the memory requested.
  76     @result Pointer to the allocated memory, or zero on failure. */
  77
  78 void * IOMalloc(vm_size_t size);
  79
  80 /*! @function IOFree
  81     @abstract Frees memory allocated with IOMalloc.
  82     @discussion This function frees memory allocated with IOMalloc, it may block and so should not be called from interrupt level or while a simple lock is held.
  83     @param address Pointer to the allocated memory.
  84     @param size Size of the memory allocated. */
  85
  86 void   IOFree(void * address, vm_size_t size);
  87
  88 /*! @function IOMallocAligned
  89     @abstract Allocates wired memory in the kernel map, with an alignment restriction.
  90     @discussion This is a utility to allocate memory in the kernel, with an alignment restriction which is specified as a byte count. This function may block and so should not be called from interrupt level or while a simple lock is held.
  91     @param size Size of the memory requested.
  92     @param alignment Byte count of the alignment for the memory. For example, pass 256 to get memory allocated at an address with bit 0-7 zero.
  93     @result Pointer to the allocated memory, or zero on failure. */
  94
  95 void * IOMallocAligned(vm_size_t size, vm_offset_t alignment);
  96
  97 /*! @function IOFreeAligned
  98     @abstract Frees memory allocated with IOMallocAligned.
  99     @discussion This function frees memory allocated with IOMallocAligned, it may block and so should not be called from interrupt level or while a simple lock is held.
 100     @param address Pointer to the allocated memory.
 101     @param size Size of the memory allocated. */
 102
 103 void   IOFreeAligned(void * address, vm_size_t size);
 104
 105 /*! @function IOMallocContiguous
 106     @abstract Allocates wired memory in the kernel map, with an alignment restriction and physically contiguous.
 107     @discussion This is a utility to allocate memory in the kernel, with an alignment restriction which is specified as a byte count, and will allocate only physically contiguous memory. The request may fail if memory is fragmented, and may cause large amounts of paging activity. This function may block and so should not be called from interrupt level or while a simple lock is held.
 108     @param size Size of the memory requested.
 109     @param alignment Byte count of the alignment for the memory. For example, pass 256 to get memory allocated at an address with bits 0-7 zero.
 110     @param physicalAddress IOMallocContiguous returns the physical address of the allocated memory here, if physicalAddress is a non-zero pointer.
 111     @result Virtual address of the allocated memory, or zero on failure. */
 112
 113 void * IOMallocContiguous(vm_size_t size, vm_size_t alignment,
 114                            IOPhysicalAddress * physicalAddress);
 115
 116 /*! @function IOFreeContiguous
 117     @abstract Frees memory allocated with IOMallocContiguous.
 118     @discussion This function frees memory allocated with IOMallocContiguous, it may block and so should not be called from interrupt level or while a simple lock is held.
 119     @param address Virtual address of the allocated memory.
 120     @param size Size of the memory allocated. */
 121
 122 void   IOFreeContiguous(void * address, vm_size_t size);
 123
 124
 125 /*! @function IOMallocPageable
 126     @abstract Allocates pageable memory in the kernel map.
 127     @discussion This is a utility to allocate pageable memory in the kernel. This function may block and so should not be called from interrupt level or while a simple lock is held.
 128     @param size Size of the memory requested.
 129     @param alignment Byte count of the alignment for the memory. For example, pass 256 to get memory allocated at an address with bits 0-7 zero.
 130     @result Pointer to the allocated memory, or zero on failure. */
 131
 132 void * IOMallocPageable(vm_size_t size, vm_size_t alignment);
 133
 134 /*! @function IOFreePageable
 135     @abstract Frees memory allocated with IOMallocPageable.
 136     @discussion This function frees memory allocated with IOMallocPageable, it may block and so should not be called from interrupt level or while a simple lock is held.
 137     @param address Virtual address of the allocated memory.
 138     @param size Size of the memory allocated. */
 139
 140 void IOFreePageable(void * address, vm_size_t size);
 141
 142 /*
 143  * Typed memory allocation macros. Both may block.
 144  */
 145 #define IONew(type,number)        (type*)IOMalloc(sizeof(type) * (number) )
 146 #define IODelete(ptr,type,number) IOFree( (ptr) , sizeof(type) * (number) )
 147
 148 /*! @function IOSetProcessorCacheMode
 149     @abstract Sets the processor cache mode for mapped memory.
 150     @discussion This function sets the cache mode of an already mapped & wired memory range. Note this may not be supported on I/O mappings or shared memory - it is far preferable to set the cache mode as mappings are created with the IOMemoryDescriptor::map method.
 151     @param task Task the memory is mapped into.
 152     @param address Virtual address of the memory.
 153     @param length Length of the range to set.
 154     @param cacheMode A constant from IOTypes.h, <br>
 155         kIOMapDefaultCache to inhibit the cache in I/O areas, kIOMapCopybackCache in general purpose RAM.<br>
 156         kIOMapInhibitCache, kIOMapWriteThruCache, kIOMapCopybackCache to set the appropriate caching.<br>
 157     @result An IOReturn code.*/
 158
 159 IOReturn IOSetProcessorCacheMode( task_t task, IOVirtualAddress address,
 160                                   IOByteCount length, IOOptionBits cacheMode );
 161
 162 /*! @function IOFlushProcessorCache
 163     @abstract Flushes the processor cache for mapped memory.
 164     @discussion This function flushes the processor cache of an already mapped memory range. Note in most cases it is preferable to use IOMemoryDescriptor::prepare and complete to manage cache coherency since they are aware of the architecture's requirements. Flushing the processor cache is not required for coherency in most situations.
 165     @param task Task the memory is mapped into.
 166     @param address Virtual address of the memory.
 167     @param length Length of the range to set.
 168     @result An IOReturn code. */
 169
 170 IOReturn IOFlushProcessorCache( task_t task, IOVirtualAddress address,
 171                                   IOByteCount length );
 172
 173 /*! @function IOThreadSelf
 174     @abstract Returns the osfmk identifier for the currently running thread.
 175     @discussion This function returns the current thread (a pointer to the currently active osfmk thread_shuttle). */
 176
 177 #define IOThreadSelf() (current_thread())
 178
 179 /*! @function IOCreateThread
 180     @abstract Create a kernel thread.
 181     @discussion This function creates a kernel thread, and passes the caller supplied argument to the new thread.
 182     @param function A C-function pointer where the thread will begin execution.
 183     @param argument Caller specified data to be passed to the new thread.
 184     @result An IOThread identifier for the new thread, equivalent to an osfmk thread_t. */
 185
 186 IOThread IOCreateThread(IOThreadFunc function, void *argument);
 187
 188 /*! @function IOExitThread
 189     @abstract Terminate exceution of current thread.
 190     @discussion This function destroys the currently running thread, and does not return. */
 191
 192 volatile void IOExitThread();
 193
 194 /*! @function IOSleep
 195     @abstract Sleep the calling thread for a number of milliseconds.
 196     @discussion This function blocks the calling thread for at least the number of specified milliseconds, giving time to other processes.
 197     @param milliseconds The integer number of milliseconds to wait. */
 198
 199 void IOSleep(unsigned milliseconds);
 200
 201 /*! @function IODelay
 202     @abstract Spin delay for a number of microseconds.
 203     @discussion This function spins to delay for at least the number of specified microseconds. Since the CPU is busy spinning no time is made available to other processes; this method of delay should be used only for short periods. Also, the AbsoluteTime based APIs of kern/clock.h provide finer grained and lower cost delays.
 204     @param microseconds The integer number of microseconds to spin wait. */
 205
 206 void IODelay(unsigned microseconds);
 207
 208 /*! @function IOLog
 209     @abstract Log a message to console in text mode, and /var/log/system.log.
 210     @discussion This function allows a driver to log diagnostic information to the screen during verbose boots, and to a log file found at /var/log/system.log. IOLog should not be called from interrupt context.
 211     @param format A printf() style format string (see printf() documentation).
 212     @param other arguments described by the format string. */
 213
 214 void IOLog(const char *format, ...)
 215 __attribute__((format(printf, 1, 2)));
 216
 217 void kprintf(const char *format, ...);
 218
 219 /*
 220  * Convert a integer constant (typically a #define or enum) to a string
 221  * via an array of IONamedValue.
 222  */
 223 const char *IOFindNameForValue(int value,
 224         const IONamedValue *namedValueArray);
 225
 226 /*
 227  * Convert a string to an int via an array of IONamedValue. Returns
 228  * kIOReturnSuccess of string found, else returns kIOReturnBadArgument.
 229  */
 230 IOReturn IOFindValueForName(const char *string,
 231         const IONamedValue *regValueArray,
 232         int *value);                            /* RETURNED */
 233
 234 /*! @function Debugger
 235     @abstract Enter the kernel debugger.
 236     @discussion This function freezes the kernel and enters the builtin debugger. It may not be possible to exit the debugger without a second machine.
 237     @param reason A C-string to describe why the debugger is being entered. */
 238
 239 void Debugger(const char * reason);
 240
 241 struct OSDictionary * IOBSDNameMatching( const char * name );
 242 struct OSDictionary * IOOFPathMatching( const char * path, char * buf, int maxLen );
 243
 244 /*
 245  * Convert between size and a power-of-two alignment.
 246  */
 247 IOAlignment IOSizeToAlignment(unsigned int size);
 248 unsigned int IOAlignmentToSize(IOAlignment align);
 249
 250 /*
 251  * Multiply and divide routines for IOFixed datatype.
 252  */
 253
 254 static inline IOFixed IOFixedMultiply(IOFixed a, IOFixed b)
 255 {
 256     return (IOFixed)((((SInt64) a) * ((SInt64) b)) >> 16);
 257 }
 258
 259 static inline IOFixed IOFixedDivide(IOFixed a, IOFixed b)
 260 {
 261     return (IOFixed)((((SInt64) a) << 16) / ((SInt64) b));
 262 }
 263
 264 /*
 265  * IORound and IOTrunc convenience functions, in the spirit
 266  * of vm's round_page() and trunc_page().
 267  */
 268 #define IORound(value,multiple) \
 269         ((((value) + (multiple) - 1) / (multiple)) * (multiple))
 270
 271 #define IOTrunc(value,multiple) \
 272         (((value) / (multiple)) * (multiple));
 273
 274
 275 #if IOKIT_DEPRECATED
 276
 277 /* The following API is deprecated */
 278
 279 #undef eieio
 280 #define eieio() \
 281     OSSynchronizeIO()
 282
 283 void IOPanic(const char *reason);
 284
 285 /* The API exported by kern/clock.h
 286    should be used for high resolution timing. */
 287
 288 void IOGetTime( mach_timespec_t * clock_time);
 289
 290 extern mach_timespec_t IOZeroTvalspec;
 291
 292 #endif /* IOKIT_DEPRECATED */
 293
 294 #ifdef __cplusplus
 295 } /* extern "C" */
 296 #endif
 297
 298 #endif /* !__IOKIT_IOLIB_H */