diff options
| -rw-r--r-- | drivers/dma-buf/heaps/cma_heap.c | 319 |
1 files changed, 270 insertions, 49 deletions
diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c index e55384dc115b..05aaa4f29397 100644 --- a/drivers/dma-buf/heaps/cma_heap.c +++ b/drivers/dma-buf/heaps/cma_heap.c @@ -2,76 +2,295 @@ /* * DMABUF CMA heap exporter * - * Copyright (C) 2012, 2019 Linaro Ltd. + * Copyright (C) 2012, 2019, 2020 Linaro Ltd. * Author: <benjamin.gaignard@linaro.org> for ST-Ericsson. + * + * Also utilizing parts of Andrew Davis' SRAM heap: + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/ + * Andrew F. Davis <afd@ti.com> */ - #include <linux/cma.h> -#include <linux/device.h> #include <linux/dma-buf.h> #include <linux/dma-heap.h> #include <linux/dma-map-ops.h> #include <linux/err.h> -#include <linux/errno.h> #include <linux/highmem.h> +#include <linux/io.h> +#include <linux/mm.h> #include <linux/module.h> -#include <linux/slab.h> #include <linux/scatterlist.h> -#include <linux/sched/signal.h> +#include <linux/slab.h> -#include "heap-helpers.h" struct cma_heap { struct dma_heap *heap; struct cma *cma; }; -static void cma_heap_free(struct heap_helper_buffer *buffer) +struct cma_heap_buffer { + struct cma_heap *heap; + struct list_head attachments; + struct mutex lock; + unsigned long len; + struct page *cma_pages; + struct page **pages; + pgoff_t pagecount; + int vmap_cnt; + void *vaddr; +}; + +struct dma_heap_attachment { + struct device *dev; + struct sg_table table; + struct list_head list; +}; + +static int cma_heap_attach(struct dma_buf *dmabuf, + struct dma_buf_attachment *attachment) { - struct cma_heap *cma_heap = dma_heap_get_drvdata(buffer->heap); - unsigned long nr_pages = buffer->pagecount; - struct page *cma_pages = buffer->priv_virt; + struct cma_heap_buffer *buffer = dmabuf->priv; + struct dma_heap_attachment *a; + int ret; - /* free page list */ - kfree(buffer->pages); - /* release memory */ - cma_release(cma_heap->cma, cma_pages, nr_pages); + a = kzalloc(sizeof(*a), GFP_KERNEL); + if (!a) + return -ENOMEM; + + ret = sg_alloc_table_from_pages(&a->table, buffer->pages, + buffer->pagecount, 0, + buffer->pagecount << PAGE_SHIFT, + GFP_KERNEL); + if (ret) { + kfree(a); + return ret; + } + + a->dev = attachment->dev; + INIT_LIST_HEAD(&a->list); + + attachment->priv = a; + + mutex_lock(&buffer->lock); + list_add(&a->list, &buffer->attachments); + mutex_unlock(&buffer->lock); + + return 0; +} + +static void cma_heap_detach(struct dma_buf *dmabuf, + struct dma_buf_attachment *attachment) +{ + struct cma_heap_buffer *buffer = dmabuf->priv; + struct dma_heap_attachment *a = attachment->priv; + + mutex_lock(&buffer->lock); + list_del(&a->list); + mutex_unlock(&buffer->lock); + + sg_free_table(&a->table); + kfree(a); +} + +static struct sg_table *cma_heap_map_dma_buf(struct dma_buf_attachment *attachment, + enum dma_data_direction direction) +{ + struct dma_heap_attachment *a = attachment->priv; + struct sg_table *table = &a->table; + int ret; + + ret = dma_map_sgtable(attachment->dev, table, direction, 0); + if (ret) + return ERR_PTR(-ENOMEM); + return table; +} + +static void cma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment, + struct sg_table *table, + enum dma_data_direction direction) +{ + dma_unmap_sgtable(attachment->dev, table, direction, 0); +} + +static int cma_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf, + enum dma_data_direction direction) +{ + struct cma_heap_buffer *buffer = dmabuf->priv; + struct dma_heap_attachment *a; + + if (buffer->vmap_cnt) + invalidate_kernel_vmap_range(buffer->vaddr, buffer->len); + + mutex_lock(&buffer->lock); + list_for_each_entry(a, &buffer->attachments, list) { + dma_sync_sgtable_for_cpu(a->dev, &a->table, direction); + } + mutex_unlock(&buffer->lock); + + return 0; +} + +static int cma_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf, + enum dma_data_direction direction) +{ + struct cma_heap_buffer *buffer = dmabuf->priv; + struct dma_heap_attachment *a; + + if (buffer->vmap_cnt) + flush_kernel_vmap_range(buffer->vaddr, buffer->len); + + mutex_lock(&buffer->lock); + list_for_each_entry(a, &buffer->attachments, list) { + dma_sync_sgtable_for_device(a->dev, &a->table, direction); + } + mutex_unlock(&buffer->lock); + + return 0; +} + +static vm_fault_t cma_heap_vm_fault(struct vm_fault *vmf) +{ + struct vm_area_struct *vma = vmf->vma; + struct cma_heap_buffer *buffer = vma->vm_private_data; + + if (vmf->pgoff > buffer->pagecount) + return VM_FAULT_SIGBUS; + + vmf->page = buffer->pages[vmf->pgoff]; + get_page(vmf->page); + + return 0; +} + +static const struct vm_operations_struct dma_heap_vm_ops = { + .fault = cma_heap_vm_fault, +}; + +static int cma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) +{ + struct cma_heap_buffer *buffer = dmabuf->priv; + + if ((vma->vm_flags & (VM_SHARED | VM_MAYSHARE)) == 0) + return -EINVAL; + + vma->vm_ops = &dma_heap_vm_ops; + vma->vm_private_data = buffer; + + return 0; +} + +static void *cma_heap_do_vmap(struct cma_heap_buffer *buffer) +{ + void *vaddr; + + vaddr = vmap(buffer->pages, buffer->pagecount, VM_MAP, PAGE_KERNEL); + if (!vaddr) + return ERR_PTR(-ENOMEM); + + return vaddr; +} + +static int cma_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map) +{ + struct cma_heap_buffer *buffer = dmabuf->priv; + void *vaddr; + int ret = 0; + + mutex_lock(&buffer->lock); + if (buffer->vmap_cnt) { + buffer->vmap_cnt++; + dma_buf_map_set_vaddr(map, buffer->vaddr); + goto out; + } + + vaddr = cma_heap_do_vmap(buffer); + if (IS_ERR(vaddr)) { + ret = PTR_ERR(vaddr); + goto out; + } + buffer->vaddr = vaddr; + buffer->vmap_cnt++; + dma_buf_map_set_vaddr(map, buffer->vaddr); +out: + mutex_unlock(&buffer->lock); + + return ret; +} + +static void cma_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map) +{ + struct cma_heap_buffer *buffer = dmabuf->priv; + + mutex_lock(&buffer->lock); + if (!--buffer->vmap_cnt) { + vunmap(buffer->vaddr); + buffer->vaddr = NULL; + } + mutex_unlock(&buffer->lock); + dma_buf_map_clear(map); +} + +static void cma_heap_dma_buf_release(struct dma_buf *dmabuf) +{ + struct cma_heap_buffer *buffer = dmabuf->priv; + struct cma_heap *cma_heap = buffer->heap; + + if (buffer->vmap_cnt > 0) { + WARN(1, "%s: buffer still mapped in the kernel\n", __func__); + vunmap(buffer->vaddr); + buffer->vaddr = NULL; + } + + cma_release(cma_heap->cma, buffer->cma_pages, buffer->pagecount); kfree(buffer); } -/* dmabuf heap CMA operations functions */ +static const struct dma_buf_ops cma_heap_buf_ops = { + .attach = cma_heap_attach, + .detach = cma_heap_detach, + .map_dma_buf = cma_heap_map_dma_buf, + .unmap_dma_buf = cma_heap_unmap_dma_buf, + .begin_cpu_access = cma_heap_dma_buf_begin_cpu_access, + .end_cpu_access = cma_heap_dma_buf_end_cpu_access, + .mmap = cma_heap_mmap, + .vmap = cma_heap_vmap, + .vunmap = cma_heap_vunmap, + .release = cma_heap_dma_buf_release, +}; + static int cma_heap_allocate(struct dma_heap *heap, - unsigned long len, - unsigned long fd_flags, - unsigned long heap_flags) + unsigned long len, + unsigned long fd_flags, + unsigned long heap_flags) { struct cma_heap *cma_heap = dma_heap_get_drvdata(heap); - struct heap_helper_buffer *helper_buffer; - struct page *cma_pages; + struct cma_heap_buffer *buffer; + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); size_t size = PAGE_ALIGN(len); - unsigned long nr_pages = size >> PAGE_SHIFT; + pgoff_t pagecount = size >> PAGE_SHIFT; unsigned long align = get_order(size); + struct page *cma_pages; struct dma_buf *dmabuf; int ret = -ENOMEM; pgoff_t pg; - if (align > CONFIG_CMA_ALIGNMENT) - align = CONFIG_CMA_ALIGNMENT; - - helper_buffer = kzalloc(sizeof(*helper_buffer), GFP_KERNEL); - if (!helper_buffer) + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); + if (!buffer) return -ENOMEM; - init_heap_helper_buffer(helper_buffer, cma_heap_free); - helper_buffer->heap = heap; - helper_buffer->size = len; + INIT_LIST_HEAD(&buffer->attachments); + mutex_init(&buffer->lock); + buffer->len = size; + + if (align > CONFIG_CMA_ALIGNMENT) + align = CONFIG_CMA_ALIGNMENT; - cma_pages = cma_alloc(cma_heap->cma, nr_pages, align, false); + cma_pages = cma_alloc(cma_heap->cma, pagecount, align, false); if (!cma_pages) - goto free_buf; + goto free_buffer; + /* Clear the cma pages */ if (PageHighMem(cma_pages)) { - unsigned long nr_clear_pages = nr_pages; + unsigned long nr_clear_pages = pagecount; struct page *page = cma_pages; while (nr_clear_pages > 0) { @@ -85,7 +304,6 @@ static int cma_heap_allocate(struct dma_heap *heap, */ if (fatal_signal_pending(current)) goto free_cma; - page++; nr_clear_pages--; } @@ -93,28 +311,30 @@ static int cma_heap_allocate(struct dma_heap *heap, memset(page_address(cma_pages), 0, size); } - helper_buffer->pagecount = nr_pages; - helper_buffer->pages = kmalloc_array(helper_buffer->pagecount, - sizeof(*helper_buffer->pages), - GFP_KERNEL); - if (!helper_buffer->pages) { + buffer->pages = kmalloc_array(pagecount, sizeof(*buffer->pages), GFP_KERNEL); + if (!buffer->pages) { ret = -ENOMEM; goto free_cma; } - for (pg = 0; pg < helper_buffer->pagecount; pg++) - helper_buffer->pages[pg] = &cma_pages[pg]; + for (pg = 0; pg < pagecount; pg++) + buffer->pages[pg] = &cma_pages[pg]; + + buffer->cma_pages = cma_pages; + buffer->heap = cma_heap; + buffer->pagecount = pagecount; /* create the dmabuf */ - dmabuf = heap_helper_export_dmabuf(helper_buffer, fd_flags); + exp_info.ops = &cma_heap_buf_ops; + exp_info.size = buffer->len; + exp_info.flags = fd_flags; + exp_info.priv = buffer; + dmabuf = dma_buf_export(&exp_info); if (IS_ERR(dmabuf)) { ret = PTR_ERR(dmabuf); goto free_pages; } - helper_buffer->dmabuf = dmabuf; - helper_buffer->priv_virt = cma_pages; - ret = dma_buf_fd(dmabuf, fd_flags); if (ret < 0) { dma_buf_put(dmabuf); @@ -125,11 +345,12 @@ static int cma_heap_allocate(struct dma_heap *heap, return ret; free_pages: - kfree(helper_buffer->pages); + kfree(buffer->pages); free_cma: - cma_release(cma_heap->cma, cma_pages, nr_pages); -free_buf: - kfree(helper_buffer); + cma_release(cma_heap->cma, cma_pages, pagecount); +free_buffer: + kfree(buffer); + return ret; } |