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Diffstat (limited to 'drivers/cenalloc/cenalloc.h')
| -rw-r--r-- | drivers/cenalloc/cenalloc.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/cenalloc/cenalloc.h b/drivers/cenalloc/cenalloc.h new file mode 100644 index 000000000000..91e07b246f1c --- /dev/null +++ b/drivers/cenalloc/cenalloc.h @@ -0,0 +1,99 @@ +/* + * Header file for allocator helper framework for constraints-aware + * dma-buf backing storage allocation. + * + * Copyright(C) 2014 Linaro Limited. All rights reserved. + * Author: Sumit Semwal <sumit.semwal@linaro.org> + * + * Structure for management of device, buffers etc heavily derived from + * Android's ION framework. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * 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. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#ifndef CENALLOC_H_ +#define CENALLOC_H_ + +#include <linux/types.h> +#include <linux/dma-buf.h> + +struct cenalloc_device; + +/** + * cenalloc_get_device: + * gets a reference to cenalloc_device; this should be used in the + * call to cenalloc_buffer_create. + * + * TODO: might need to have a better way of getting this device. + */ +const struct cenalloc_device *cenalloc_get_device(void); + +/** + * cenalloc_buffer_create: + * creates a cenalloc_buffer, associates a dma_buf buffer with it, + * and returns the dma_buf; other importers can then use references + * to this dma_buf and attach themselves to it. + * + * Note: Since this is delayed-allocation model, no actual allocation + * will happen at this call. + * + * @dev: cenalloc_device to create the buffer from + * @len: size of the buffer + * @align: alignment info, if any + * @flags: flags for the buffer, if any + * + */ +struct dma_buf *cenalloc_buffer_create(struct cenalloc_device *dev, + unsigned long len, + unsigned long align, + unsigned long flags); + +/** + * cenalloc_buffer_free: + * calls dma_buf_put(), which in turn may call allocator->free() + * if this was the last reference held. + * For dma-bufs created with cenalloc_buffer_create, this should be + * called instead of dma_buf_put() directly. + * + * @dma_buf: the dma_buf to free. + */ +void cenalloc_buffer_free(struct dma_buf *dmabuf); + +/** + * cenalloc_phys: + * returns the phys address and len associated with this buffer - this + * will get refined as the ION 'abuse' of phys_addr_t is corrected. + * This is valid only for buffers that are allocated from physically + * contiguous memory; its output is invalid otherwise. For such cases, + * cenalloc_sg_table() should be used instead. + * Will return -EINVAL if the buffer is invalid. + * + * @dmabuf: buffer for which phys address is needed + * @phys: pointer to the phys address + * @len: pointer to teh length of the buffer + * + */ +int cenalloc_phys(struct dma_buf *dmabuf, + phys_addr_t *addr, size_t *len); + +/** + * cenalloc_sg_table: + * returns the sg_table associated with the dma_buf. + * Will return -EINVAL in case of error. + * + * @dmabuf: handle to buffer who's sg_table is to be returned. + * + */ +struct sg_table *cenalloc_sg_table(struct dma_buf *dmabuf); + +#endif /* CENALLOC_H_ */ |