/* * 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 _LINUX_ION_H #define _LINUX_ION_H #include <linux/types.h> struct ion_handle; /** * 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_END: helper for iterating over heaps */ enum ion_heap_type { ION_HEAP_TYPE_SYSTEM, ION_HEAP_TYPE_SYSTEM_CONTIG, ION_HEAP_TYPE_CARVEOUT, ION_HEAP_TYPE_CUSTOM, /* must be last so device specific heaps always are at the end of this enum */ ION_NUM_HEAPS, }; #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) #ifdef __KERNEL__ struct ion_device; struct ion_heap; struct ion_mapper; struct ion_client; struct ion_buffer; /* This should be removed some day when phys_addr_t's are fully plumbed in the kernel, and all instances of ion_phys_addr_t should be converted to phys_addr_t. For the time being many kernel interfaces do not accept phys_addr_t's that would have to */ #define ion_phys_addr_t unsigned long /** * struct ion_platform_heap - defines a heap in the given platform * @type: type of the heap from ion_heap_type enum * @id: unique identifier for heap. When allocating (lower numbers * will be allocated from first) * @name: used for debug purposes * @base: base address of heap in physical memory if applicable * @size: size of the heap in bytes if applicable * * Provided by the board file. */ struct ion_platform_heap { enum ion_heap_type type; unsigned int id; const char *name; ion_phys_addr_t base; size_t size; }; /** * struct ion_platform_data - array of platform heaps passed from board file * @nr: number of structures in the array * @heaps: array of platform_heap structions * * Provided by the board file in the form of platform data to a platform device. */ struct ion_platform_data { int nr; struct ion_platform_heap heaps[]; }; /** * ion_client_create() - allocate a client and returns it * @dev: the global ion device * @heap_mask: mask of heaps this client can allocate from * @name: used for debugging */ struct ion_client *ion_client_create(struct ion_device *dev, unsigned int heap_mask, const char *name); /** * ion_client_destroy() - free's a client and all it's handles * @client: the client * * Free the provided client and all it's resources including * any handles it is holding. */ void ion_client_destroy(struct ion_client *client); /** * ion_alloc - allocate ion memory * @client: the client * @len: size of the allocation * @align: requested allocation alignment, lots of hardware blocks have * alignment requirements of some kind * @flags: mask of heaps to allocate from, if multiple bits are set * heaps will be tried in order from lowest to highest order bit * * Allocate memory in one of the heaps provided in heap mask and return * an opaque handle to it. */ struct ion_handle *ion_alloc(struct ion_client *client, size_t len, size_t align, unsigned int flags); /** * ion_free - free a handle * @client: the client * @handle: the handle to free * * Free the provided handle. */ void ion_free(struct ion_client *client, struct ion_handle *handle); /** * ion_phys - returns the physical address and len of a handle * @client: the client * @handle: the handle * @addr: a pointer to put the address in * @len: a pointer to put the length in * * This function queries the heap for a particular handle to get the * handle's physical address. It't output is only correct if * a heap returns physically contiguous memory -- in other cases * this api should not be implemented -- ion_map_dma should be used * instead. Returns -EINVAL if the handle is invalid. This has * no implications on the reference counting of the handle -- * the returned value may not be valid if the caller is not * holding a reference. */ int ion_phys(struct ion_client *client, struct ion_handle *handle, ion_phys_addr_t *addr, size_t *len); /** * ion_map_kernel - create mapping for the given handle * @client: the client * @handle: handle to map * * Map the given handle into the kernel and return a kernel address that * can be used to access this address. */ void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle); /** * ion_unmap_kernel() - destroy a kernel mapping for a handle * @client: the client * @handle: handle to unmap */ void ion_unmap_kernel(struct ion_client *client, struct ion_handle *handle); /** * ion_map_dma - create a dma mapping for a given handle * @client: the client * @handle: handle to map * * Return an sglist describing the given handle */ struct scatterlist *ion_map_dma(struct ion_client *client, struct ion_handle *handle); /** * ion_unmap_dma() - destroy a dma mapping for a handle * @client: the client * @handle: handle to unmap */ void ion_unmap_dma(struct ion_client *client, struct ion_handle *handle); /** * ion_share() - given a handle, obtain a buffer to pass to other clients * @client: the client * @handle: the handle to share * * Given a handle, return a buffer, which exists in a global name * space, and can be passed to other clients. Should be passed into ion_import * to obtain a new handle for this buffer. * * NOTE: This function does do not an extra reference. The burden is on the * caller to make sure the buffer doesn't go away while it's being passed to * another client. That is, ion_free should not be called on this handle until * the buffer has been imported into the other client. */ struct ion_buffer *ion_share(struct ion_client *client, struct ion_handle *handle); /** * ion_import() - given an buffer in another client, import it * @client: this blocks client * @buffer: the buffer to import (as obtained from ion_share) * * Given a buffer, add it to the client and return the handle to use to refer * to it further. This is called to share a handle from one kernel client to * another. */ struct ion_handle *ion_import(struct ion_client *client, struct ion_buffer *buffer); /** * ion_import_fd() - given an fd obtained via ION_IOC_SHARE ioctl, import it * @client: this blocks client * @fd: the fd * * A helper function for drivers that will be recieving ion buffers shared * with them from userspace. These buffers are represented by a file * descriptor obtained as the return from the ION_IOC_SHARE ioctl. * This function coverts that fd into the underlying buffer, and returns * the handle to use to refer to it further. */ struct ion_handle *ion_import_fd(struct ion_client *client, int fd); #endif /* __KERNEL__ */ /** * 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 * @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 flags; struct ion_handle *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 { struct ion_handle *handle; int fd; }; /** * struct ion_handle_data - a handle passed to/from the kernel * @handle: a handle */ struct ion_handle_data { struct ion_handle *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, int) /** * 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 /* _LINUX_ION_H */