/* * include/linux/ion.h * * Copyright (C) 2011 Google, Inc. * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * */ #ifndef _UAPI_ION_H #define _UAPI_ION_H #include #include typedef int ion_user_handle_t; /** * enum ion_heap_types - list of all possible types of heaps * @ION_HEAP_TYPE_SYSTEM: memory allocated via vmalloc * @ION_HEAP_TYPE_SYSTEM_CONTIG: memory allocated via kmalloc * @ION_HEAP_TYPE_CARVEOUT: memory allocated from a prereserved * carveout heap, allocations are physically * contiguous * @ION_HEAP_TYPE_DMA: memory allocated via DMA API * @ION_NUM_HEAPS: helper for iterating over heaps, a bit mask * is used to identify the heaps, so only 32 * total heap types are supported */ enum ion_heap_type { ION_HEAP_TYPE_SYSTEM, ION_HEAP_TYPE_SYSTEM_CONTIG, ION_HEAP_TYPE_CARVEOUT, ION_HEAP_TYPE_CHUNK, ION_HEAP_TYPE_DMA, ION_HEAP_TYPE_CUSTOM, /* must be last so device specific heaps always are at the end of this enum */ ION_NUM_HEAPS = 16, }; #define ION_HEAP_SYSTEM_MASK (1 << ION_HEAP_TYPE_SYSTEM) #define ION_HEAP_SYSTEM_CONTIG_MASK (1 << ION_HEAP_TYPE_SYSTEM_CONTIG) #define ION_HEAP_CARVEOUT_MASK (1 << ION_HEAP_TYPE_CARVEOUT) #define ION_HEAP_TYPE_DMA_MASK (1 << ION_HEAP_TYPE_DMA) #define ION_NUM_HEAP_IDS sizeof(unsigned int) * 8 /** * allocation flags - the lower 16 bits are used by core ion, the upper 16 * bits are reserved for use by the heaps themselves. */ #define ION_FLAG_CACHED 1 /* mappings of this buffer should be cached, ion will do cache maintenance when the buffer is mapped for dma */ #define ION_FLAG_CACHED_NEEDS_SYNC 2 /* mappings of this buffer will created at mmap time, if this is set caches must be managed manually */ /** * DOC: Ion Userspace API * * create a client by opening /dev/ion * most operations handled via following ioctls * */ /** * struct ion_allocation_data - metadata passed from userspace for allocations * @len: size of the allocation * @align: required alignment of the allocation * @heap_id_mask: mask of heap ids to allocate from * @flags: flags passed to heap * @handle: pointer that will be populated with a cookie to use to * refer to this allocation * * Provided by userspace as an argument to the ioctl */ struct ion_allocation_data { size_t len; size_t align; unsigned int heap_id_mask; unsigned int flags; ion_user_handle_t handle; }; /** * struct ion_fd_data - metadata passed to/from userspace for a handle/fd pair * @handle: a handle * @fd: a file descriptor representing that handle * * For ION_IOC_SHARE or ION_IOC_MAP userspace populates the handle field with * the handle returned from ion alloc, and the kernel returns the file * descriptor to share or map in the fd field. For ION_IOC_IMPORT, userspace * provides the file descriptor and the kernel returns the handle. */ struct ion_fd_data { ion_user_handle_t handle; int fd; }; /** * struct ion_handle_data - a handle passed to/from the kernel * @handle: a handle */ struct ion_handle_data { ion_user_handle_t handle; }; /** * struct ion_custom_data - metadata passed to/from userspace for a custom ioctl * @cmd: the custom ioctl function to call * @arg: additional data to pass to the custom ioctl, typically a user * pointer to a predefined structure * * This works just like the regular cmd and arg fields of an ioctl. */ struct ion_custom_data { unsigned int cmd; unsigned long arg; }; #define ION_IOC_MAGIC 'I' /** * DOC: ION_IOC_ALLOC - allocate memory * * Takes an ion_allocation_data struct and returns it with the handle field * populated with the opaque handle for the allocation. */ #define ION_IOC_ALLOC _IOWR(ION_IOC_MAGIC, 0, \ struct ion_allocation_data) /** * DOC: ION_IOC_FREE - free memory * * Takes an ion_handle_data struct and frees the handle. */ #define ION_IOC_FREE _IOWR(ION_IOC_MAGIC, 1, struct ion_handle_data) /** * DOC: ION_IOC_MAP - get a file descriptor to mmap * * Takes an ion_fd_data struct with the handle field populated with a valid * opaque handle. Returns the struct with the fd field set to a file * descriptor open in the current address space. This file descriptor * can then be used as an argument to mmap. */ #define ION_IOC_MAP _IOWR(ION_IOC_MAGIC, 2, struct ion_fd_data) /** * DOC: ION_IOC_SHARE - creates a file descriptor to use to share an allocation * * Takes an ion_fd_data struct with the handle field populated with a valid * opaque handle. Returns the struct with the fd field set to a file * descriptor open in the current address space. This file descriptor * can then be passed to another process. The corresponding opaque handle can * be retrieved via ION_IOC_IMPORT. */ #define ION_IOC_SHARE _IOWR(ION_IOC_MAGIC, 4, struct ion_fd_data) /** * DOC: ION_IOC_IMPORT - imports a shared file descriptor * * Takes an ion_fd_data struct with the fd field populated with a valid file * descriptor obtained from ION_IOC_SHARE and returns the struct with the handle * filed set to the corresponding opaque handle. */ #define ION_IOC_IMPORT _IOWR(ION_IOC_MAGIC, 5, struct ion_fd_data) /** * DOC: ION_IOC_SYNC - syncs a shared file descriptors to memory * * Deprecated in favor of using the dma_buf api's correctly (syncing * will happend automatically when the buffer is mapped to a device). * If necessary should be used after touching a cached buffer from the cpu, * this will make the buffer in memory coherent. */ #define ION_IOC_SYNC _IOWR(ION_IOC_MAGIC, 7, struct ion_fd_data) /** * DOC: ION_IOC_CUSTOM - call architecture specific ion ioctl * * Takes the argument of the architecture specific ioctl to call and * passes appropriate userdata for that ioctl */ #define ION_IOC_CUSTOM _IOWR(ION_IOC_MAGIC, 6, struct ion_custom_data) #endif /* _UAPI_ION_H */