DMABUF是一种在Linux中用于在不同进程或设备之间共享内存缓冲区的机制。它允许不同的驱动程序或应用程序高效地访问和操作同一块内存区域,而无需进行额外的数据复制。DMABUF的使用可以显著减少内存带宽的占用,提高系统性能。 dmabuf与anon_inode的关系在于,DMABUF通常通过匿名inode来表示。也就是说,当内核创建一个DMA...
* Unlike drm_gem_prime_handle_to_fd(), it returns the struct dma_buf it * has created, without attaching it to any file descriptors. The difference * between those two is similar to that between anon_inode_getfile() and * anon_inode_getfd(); insertion into descriptor table is something...
int buflen) { struct dma_buf *dmabuf; char name[DMA_BUF_NAME_LEN]; ssize_t ret = 0; dmabuf = dentry->d_fsdata; spin_lock(&dmabuf->name_lock); if (dmabuf->name) ret = strscpy(name, dmabuf->name, sizeof(name)); spin_unlock(&dmabuf->name_lock); return dynamic_dname(bu...
dma_buf_unmap_attachment(test_dev.attach, test_dev.sg, DMA_TO_DEVICE);dma_buf_detach(test_dev.dma_buf, test_dev.attach);dma_buf_put(test_dev.dma_buf); /* for cpu access */dma_buf_vmap(test_dev.dma_buf, &test_dev.map);printk("<%s: %d>addr = 0x%px, str = %s\n",__FUNC...
struct dma_buf *dma_buf; struct file *file; ... dmabuf = kzalloc(alloc_size, GFP_KERNEL); if(!dmabuf){ module_put(exp_info->owner); returnERR_PTR(-ENOMEM); } ... dmabuf->ops = exp_info->ops;//[0] ... file = anon_inode_getfile("dmabuf", &dma_buf_fops, dmabuf, exp...
45 size_t ret = 0; 46 47 dmabuf = dentry->d_fsdata; 48 spin_lock(&dmabuf->name_lock); 49 if (dmabuf->name) 50 ret = strlcpy(name, dmabuf->name, DMA_BUF_NAME_LEN); 51 spin_unlock(&dmabuf->name_lock); 52 53 return dynamic_dname(dentry, buffer, buflen, "/%s:%s", 54...