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+/*
+ * 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_phys_data - passed to/from userspace for a handle/phys addr pair
+ * @handle: a handle
+ * @phys: a return physcial address
+ *
+ * For ION_IOC_PHYS ioctl
+ * the phys return the ion phys address
+ */
+struct ion_phys_data {
+ struct ion_handle *handle;
+ unsigned long phys;
+};
+
+/**
+ * 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)
+
+/**
+ * DOC: ION_IOC_PHYS - get allocated memory physical address
+ *
+ * Takes an ion_fd_data struct with the handle field populated with a valid
+ * opaque handle. Returns the address
+ */
+#define ION_IOC_PHYS _IOWR(ION_IOC_MAGIC, 7, struct ion_phys_data)
+
+#endif /* _LINUX_ION_H */