1 /* 2 * Copyright (c) 2018-2020 François Tigeot <ftigeot@wolfpond.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #ifndef LINUX_DMA_BUF_H 28 #define LINUX_DMA_BUF_H 29 30 #include <linux/err.h> 31 #include <linux/scatterlist.h> 32 #include <linux/list.h> 33 #include <linux/dma-mapping.h> 34 #include <linux/fs.h> 35 #include <linux/dma-fence.h> 36 #include <linux/wait.h> 37 38 #include <linux/slab.h> 39 40 struct dma_buf; 41 struct dma_buf_attachment; 42 43 struct dma_buf_ops { 44 struct sg_table * (*map_dma_buf)(struct dma_buf_attachment *, 45 enum dma_data_direction); 46 void (*unmap_dma_buf)(struct dma_buf_attachment *, 47 struct sg_table *, 48 enum dma_data_direction); 49 void (*release)(struct dma_buf *); 50 void *(*map)(struct dma_buf *, unsigned long); 51 void *(*map_atomic)(struct dma_buf *, unsigned long); 52 void (*unmap)(struct dma_buf *, unsigned long, void *); 53 void (*unmap_atomic)(struct dma_buf *, unsigned long, void *); 54 int (*mmap)(struct dma_buf *, struct vm_area_struct *vma); 55 void *(*vmap)(struct dma_buf *); 56 void (*vunmap)(struct dma_buf *, void *vaddr); 57 int (*begin_cpu_access)(struct dma_buf *, enum dma_data_direction); 58 int (*end_cpu_access)(struct dma_buf *, enum dma_data_direction); 59 int (*attach)(struct dma_buf *, struct device *, struct dma_buf_attachment *); 60 void (*detach)(struct dma_buf *, struct dma_buf_attachment *); 61 }; 62 63 struct dma_buf { 64 struct reservation_object *resv; 65 void *priv; 66 const struct dma_buf_ops *ops; 67 size_t size; 68 struct file *file; 69 }; 70 71 struct dma_buf_attachment { 72 struct dma_buf *dmabuf; 73 struct device *dev; 74 void *priv; 75 }; 76 77 struct dma_buf_export_info { 78 const struct dma_buf_ops *ops; 79 size_t size; 80 int flags; 81 void *priv; 82 struct reservation_object *resv; 83 }; 84 85 struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info); 86 87 #define DEFINE_DMA_BUF_EXPORT_INFO(name) \ 88 struct dma_buf_export_info name = { \ 89 } 90 91 struct sg_table * dma_buf_map_attachment(struct dma_buf_attachment *, 92 enum dma_data_direction); 93 void dma_buf_unmap_attachment(struct dma_buf_attachment *, 94 struct sg_table *, enum dma_data_direction); 95 96 static inline struct dma_buf_attachment * 97 dma_buf_attach(struct dma_buf *dmabuf, struct device *dev) 98 { 99 /* XXX: this function is a stub */ 100 struct dma_buf_attachment *attach; 101 102 attach = kmalloc(sizeof(struct dma_buf_attachment), M_DRM, M_WAITOK | M_ZERO); 103 104 return attach; 105 } 106 107 static inline void 108 get_dma_buf(struct dma_buf *dmabuf) 109 { 110 fhold(dmabuf->file); 111 } 112 113 static inline void 114 dma_buf_put(struct dma_buf *dmabuf) 115 { 116 if (dmabuf == NULL) 117 return; 118 119 if (dmabuf->file == NULL) 120 return; 121 122 fdrop(dmabuf->file); 123 } 124 125 int dma_buf_fd(struct dma_buf *dmabuf, int flags); 126 127 struct dma_buf *dma_buf_get(int fd); 128 129 static inline void 130 dma_buf_detach(struct dma_buf *dmabuf, 131 struct dma_buf_attachment *dmabuf_attach) 132 { 133 kprintf("dma_buf_detach: Not implemented\n"); 134 } 135 136 #endif /* LINUX_DMA_BUF_H */ 137