iokit/Kernel/IOBufferMemoryDescriptor.cpp

100                                vm_size_t    capacity,
105     return (initWithPhysicalMask(inTask, options, capacity, alignment, physicalMask));
112 				mach_vm_size_t    capacity,
124     if (!capacity) return false;
127     _capacity         = capacity;
163 	capacity = round_page(capacity);
220                 capacity = round_page(capacity);
223             				capacity, highestMask, alignment, contig);
226 		  && ((capacity + alignment) <= (page_size - gIOPageAllocChunkBytes)))
230             _buffer         = (void *) iopa_alloc(&gIOBMDPageAllocator, &IOBMDPageProc, capacity, alignment);
233 		IOStatisticsAlloc(kIOStatisticsMallocAligned, capacity);
235 		debug_iomalloc_size += capacity;
241             _buffer = IOMallocAligned(capacity, alignment);
245             _buffer = IOMalloc(capacity);
251 	if (needZero) bzero(_buffer, capacity);
255 	vm_size_t	size = round_page(capacity);
272 	    volatile UInt8 *	endAddr   = (UInt8 *)_buffer + capacity;
326                                             vm_size_t    capacity,
331     if (me && !me->initWithPhysicalMask(inTask, options, capacity, alignment, 0)) {
341                                             mach_vm_size_t    capacity,
346     if (me && !me->initWithPhysicalMask(inTask, options, capacity, 1, physicalMask))
357                                vm_size_t    capacity,
360     return (initWithPhysicalMask(kernel_task, options, capacity, alignment, (mach_vm_address_t)0));
366                                             vm_size_t    capacity,
371     if (me && !me->initWithPhysicalMask(kernel_task, options, capacity, alignment, 0)) {
383  * hold capacity bytes.  The descriptor's length is initially set to the capacity.
401  * The descriptor's length and capacity are set to the input buffer's size.
427  * The descriptor's length and capacity are set to the input buffer's size.
535  * Get the buffer capacity
547  * the capacity.  The length can be adjusted via setLength for a shorter
550  * that the specified length must not exceed the capacity of the buffer.
580  * will not copy past the end of the memory descriptor's current capacity.