diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/dma-buf/heaps/Kconfig | 14 | ||||
| -rw-r--r-- | drivers/dma-buf/heaps/Makefile | 4 | ||||
| -rw-r--r-- | drivers/dma-buf/heaps/cma_heap.c | 177 | ||||
| -rw-r--r-- | drivers/dma-buf/heaps/heap-helpers.c | 270 | ||||
| -rw-r--r-- | drivers/dma-buf/heaps/heap-helpers.h | 53 | ||||
| -rw-r--r-- | drivers/dma-buf/heaps/system_heap.c | 123 |
6 files changed, 641 insertions, 0 deletions
diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig new file mode 100644 index 000000000..a5eef06c4 --- /dev/null +++ b/drivers/dma-buf/heaps/Kconfig @@ -0,0 +1,14 @@ +config DMABUF_HEAPS_SYSTEM + bool "DMA-BUF System Heap" + depends on DMABUF_HEAPS + help + Choose this option to enable the system dmabuf heap. The system heap + is backed by pages from the buddy allocator. If in doubt, say Y. + +config DMABUF_HEAPS_CMA + bool "DMA-BUF CMA Heap" + depends on DMABUF_HEAPS && DMA_CMA + help + Choose this option to enable dma-buf CMA heap. This heap is backed + by the Contiguous Memory Allocator (CMA). If your system has these + regions, you should say Y here. diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile new file mode 100644 index 000000000..6e54cdec3 --- /dev/null +++ b/drivers/dma-buf/heaps/Makefile @@ -0,0 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-y += heap-helpers.o +obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o +obj-$(CONFIG_DMABUF_HEAPS_CMA) += cma_heap.o diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c new file mode 100644 index 000000000..e55384dc1 --- /dev/null +++ b/drivers/dma-buf/heaps/cma_heap.c @@ -0,0 +1,177 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMABUF CMA heap exporter + * + * Copyright (C) 2012, 2019 Linaro Ltd. + * Author: <benjamin.gaignard@linaro.org> for ST-Ericsson. + */ + +#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/module.h> +#include <linux/slab.h> +#include <linux/scatterlist.h> +#include <linux/sched/signal.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 *cma_heap = dma_heap_get_drvdata(buffer->heap); + unsigned long nr_pages = buffer->pagecount; + struct page *cma_pages = buffer->priv_virt; + + /* free page list */ + kfree(buffer->pages); + /* release memory */ + cma_release(cma_heap->cma, cma_pages, nr_pages); + kfree(buffer); +} + +/* dmabuf heap CMA operations functions */ +static int cma_heap_allocate(struct dma_heap *heap, + 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; + size_t size = PAGE_ALIGN(len); + unsigned long nr_pages = size >> PAGE_SHIFT; + unsigned long align = get_order(size); + 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) + return -ENOMEM; + + init_heap_helper_buffer(helper_buffer, cma_heap_free); + helper_buffer->heap = heap; + helper_buffer->size = len; + + cma_pages = cma_alloc(cma_heap->cma, nr_pages, align, false); + if (!cma_pages) + goto free_buf; + + if (PageHighMem(cma_pages)) { + unsigned long nr_clear_pages = nr_pages; + struct page *page = cma_pages; + + while (nr_clear_pages > 0) { + void *vaddr = kmap_atomic(page); + + memset(vaddr, 0, PAGE_SIZE); + kunmap_atomic(vaddr); + /* + * Avoid wasting time zeroing memory if the process + * has been killed by by SIGKILL + */ + if (fatal_signal_pending(current)) + goto free_cma; + + page++; + nr_clear_pages--; + } + } else { + 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) { + ret = -ENOMEM; + goto free_cma; + } + + for (pg = 0; pg < helper_buffer->pagecount; pg++) + helper_buffer->pages[pg] = &cma_pages[pg]; + + /* create the dmabuf */ + dmabuf = heap_helper_export_dmabuf(helper_buffer, fd_flags); + 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); + /* just return, as put will call release and that will free */ + return ret; + } + + return ret; + +free_pages: + kfree(helper_buffer->pages); +free_cma: + cma_release(cma_heap->cma, cma_pages, nr_pages); +free_buf: + kfree(helper_buffer); + return ret; +} + +static const struct dma_heap_ops cma_heap_ops = { + .allocate = cma_heap_allocate, +}; + +static int __add_cma_heap(struct cma *cma, void *data) +{ + struct cma_heap *cma_heap; + struct dma_heap_export_info exp_info; + + cma_heap = kzalloc(sizeof(*cma_heap), GFP_KERNEL); + if (!cma_heap) + return -ENOMEM; + cma_heap->cma = cma; + + exp_info.name = cma_get_name(cma); + exp_info.ops = &cma_heap_ops; + exp_info.priv = cma_heap; + + cma_heap->heap = dma_heap_add(&exp_info); + if (IS_ERR(cma_heap->heap)) { + int ret = PTR_ERR(cma_heap->heap); + + kfree(cma_heap); + return ret; + } + + return 0; +} + +static int add_default_cma_heap(void) +{ + struct cma *default_cma = dev_get_cma_area(NULL); + int ret = 0; + + if (default_cma) + ret = __add_cma_heap(default_cma, NULL); + + return ret; +} +module_init(add_default_cma_heap); +MODULE_DESCRIPTION("DMA-BUF CMA Heap"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/dma-buf/heaps/heap-helpers.c b/drivers/dma-buf/heaps/heap-helpers.c new file mode 100644 index 000000000..d0696cf93 --- /dev/null +++ b/drivers/dma-buf/heaps/heap-helpers.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/device.h> +#include <linux/dma-buf.h> +#include <linux/err.h> +#include <linux/highmem.h> +#include <linux/idr.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <uapi/linux/dma-heap.h> + +#include "heap-helpers.h" + +void init_heap_helper_buffer(struct heap_helper_buffer *buffer, + void (*free)(struct heap_helper_buffer *)) +{ + buffer->priv_virt = NULL; + mutex_init(&buffer->lock); + buffer->vmap_cnt = 0; + buffer->vaddr = NULL; + buffer->pagecount = 0; + buffer->pages = NULL; + INIT_LIST_HEAD(&buffer->attachments); + buffer->free = free; +} + +struct dma_buf *heap_helper_export_dmabuf(struct heap_helper_buffer *buffer, + int fd_flags) +{ + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + + exp_info.ops = &heap_helper_ops; + exp_info.size = buffer->size; + exp_info.flags = fd_flags; + exp_info.priv = buffer; + + return dma_buf_export(&exp_info); +} + +static void *dma_heap_map_kernel(struct heap_helper_buffer *buffer) +{ + void *vaddr; + + vaddr = vmap(buffer->pages, buffer->pagecount, VM_MAP, PAGE_KERNEL); + if (!vaddr) + return ERR_PTR(-ENOMEM); + + return vaddr; +} + +static void dma_heap_buffer_destroy(struct heap_helper_buffer *buffer) +{ + if (buffer->vmap_cnt > 0) { + WARN(1, "%s: buffer still mapped in the kernel\n", __func__); + vunmap(buffer->vaddr); + } + + buffer->free(buffer); +} + +static void *dma_heap_buffer_vmap_get(struct heap_helper_buffer *buffer) +{ + void *vaddr; + + if (buffer->vmap_cnt) { + buffer->vmap_cnt++; + return buffer->vaddr; + } + vaddr = dma_heap_map_kernel(buffer); + if (IS_ERR(vaddr)) + return vaddr; + buffer->vaddr = vaddr; + buffer->vmap_cnt++; + return vaddr; +} + +static void dma_heap_buffer_vmap_put(struct heap_helper_buffer *buffer) +{ + if (!--buffer->vmap_cnt) { + vunmap(buffer->vaddr); + buffer->vaddr = NULL; + } +} + +struct dma_heaps_attachment { + struct device *dev; + struct sg_table table; + struct list_head list; +}; + +static int dma_heap_attach(struct dma_buf *dmabuf, + struct dma_buf_attachment *attachment) +{ + struct dma_heaps_attachment *a; + struct heap_helper_buffer *buffer = dmabuf->priv; + int ret; + + 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 dma_heap_detach(struct dma_buf *dmabuf, + struct dma_buf_attachment *attachment) +{ + struct dma_heaps_attachment *a = attachment->priv; + struct heap_helper_buffer *buffer = dmabuf->priv; + + mutex_lock(&buffer->lock); + list_del(&a->list); + mutex_unlock(&buffer->lock); + + sg_free_table(&a->table); + kfree(a); +} + +static +struct sg_table *dma_heap_map_dma_buf(struct dma_buf_attachment *attachment, + enum dma_data_direction direction) +{ + struct dma_heaps_attachment *a = attachment->priv; + struct sg_table *table = &a->table; + int ret; + + ret = dma_map_sgtable(attachment->dev, table, direction, 0); + if (ret) + table = ERR_PTR(ret); + return table; +} + +static void dma_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 vm_fault_t dma_heap_vm_fault(struct vm_fault *vmf) +{ + struct vm_area_struct *vma = vmf->vma; + struct heap_helper_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 = dma_heap_vm_fault, +}; + +static int dma_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) +{ + struct heap_helper_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 dma_heap_dma_buf_release(struct dma_buf *dmabuf) +{ + struct heap_helper_buffer *buffer = dmabuf->priv; + + dma_heap_buffer_destroy(buffer); +} + +static int dma_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf, + enum dma_data_direction direction) +{ + struct heap_helper_buffer *buffer = dmabuf->priv; + struct dma_heaps_attachment *a; + int ret = 0; + + mutex_lock(&buffer->lock); + + if (buffer->vmap_cnt) + invalidate_kernel_vmap_range(buffer->vaddr, buffer->size); + + list_for_each_entry(a, &buffer->attachments, list) { + dma_sync_sg_for_cpu(a->dev, a->table.sgl, a->table.nents, + direction); + } + mutex_unlock(&buffer->lock); + + return ret; +} + +static int dma_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf, + enum dma_data_direction direction) +{ + struct heap_helper_buffer *buffer = dmabuf->priv; + struct dma_heaps_attachment *a; + + mutex_lock(&buffer->lock); + + if (buffer->vmap_cnt) + flush_kernel_vmap_range(buffer->vaddr, buffer->size); + + list_for_each_entry(a, &buffer->attachments, list) { + dma_sync_sg_for_device(a->dev, a->table.sgl, a->table.nents, + direction); + } + mutex_unlock(&buffer->lock); + + return 0; +} + +static void *dma_heap_dma_buf_vmap(struct dma_buf *dmabuf) +{ + struct heap_helper_buffer *buffer = dmabuf->priv; + void *vaddr; + + mutex_lock(&buffer->lock); + vaddr = dma_heap_buffer_vmap_get(buffer); + mutex_unlock(&buffer->lock); + + return vaddr; +} + +static void dma_heap_dma_buf_vunmap(struct dma_buf *dmabuf, void *vaddr) +{ + struct heap_helper_buffer *buffer = dmabuf->priv; + + mutex_lock(&buffer->lock); + dma_heap_buffer_vmap_put(buffer); + mutex_unlock(&buffer->lock); +} + +const struct dma_buf_ops heap_helper_ops = { + .map_dma_buf = dma_heap_map_dma_buf, + .unmap_dma_buf = dma_heap_unmap_dma_buf, + .mmap = dma_heap_mmap, + .release = dma_heap_dma_buf_release, + .attach = dma_heap_attach, + .detach = dma_heap_detach, + .begin_cpu_access = dma_heap_dma_buf_begin_cpu_access, + .end_cpu_access = dma_heap_dma_buf_end_cpu_access, + .vmap = dma_heap_dma_buf_vmap, + .vunmap = dma_heap_dma_buf_vunmap, +}; diff --git a/drivers/dma-buf/heaps/heap-helpers.h b/drivers/dma-buf/heaps/heap-helpers.h new file mode 100644 index 000000000..805d2df88 --- /dev/null +++ b/drivers/dma-buf/heaps/heap-helpers.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * DMABUF Heaps helper code + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ + +#ifndef _HEAP_HELPERS_H +#define _HEAP_HELPERS_H + +#include <linux/dma-heap.h> +#include <linux/list.h> + +/** + * struct heap_helper_buffer - helper buffer metadata + * @heap: back pointer to the heap the buffer came from + * @dmabuf: backing dma-buf for this buffer + * @size: size of the buffer + * @priv_virt pointer to heap specific private value + * @lock mutext to protect the data in this structure + * @vmap_cnt count of vmap references on the buffer + * @vaddr vmap'ed virtual address + * @pagecount number of pages in the buffer + * @pages list of page pointers + * @attachments list of device attachments + * + * @free heap callback to free the buffer + */ +struct heap_helper_buffer { + struct dma_heap *heap; + struct dma_buf *dmabuf; + size_t size; + + void *priv_virt; + struct mutex lock; + int vmap_cnt; + void *vaddr; + pgoff_t pagecount; + struct page **pages; + struct list_head attachments; + + void (*free)(struct heap_helper_buffer *buffer); +}; + +void init_heap_helper_buffer(struct heap_helper_buffer *buffer, + void (*free)(struct heap_helper_buffer *)); + +struct dma_buf *heap_helper_export_dmabuf(struct heap_helper_buffer *buffer, + int fd_flags); + +extern const struct dma_buf_ops heap_helper_ops; +#endif /* _HEAP_HELPERS_H */ diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c new file mode 100644 index 000000000..0bf688e3c --- /dev/null +++ b/drivers/dma-buf/heaps/system_heap.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMABUF System heap exporter + * + * Copyright (C) 2011 Google, Inc. + * Copyright (C) 2019 Linaro Ltd. + */ + +#include <linux/dma-buf.h> +#include <linux/dma-mapping.h> +#include <linux/dma-heap.h> +#include <linux/err.h> +#include <linux/highmem.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/scatterlist.h> +#include <linux/slab.h> +#include <linux/sched/signal.h> +#include <asm/page.h> + +#include "heap-helpers.h" + +struct dma_heap *sys_heap; + +static void system_heap_free(struct heap_helper_buffer *buffer) +{ + pgoff_t pg; + + for (pg = 0; pg < buffer->pagecount; pg++) + __free_page(buffer->pages[pg]); + kfree(buffer->pages); + kfree(buffer); +} + +static int system_heap_allocate(struct dma_heap *heap, + unsigned long len, + unsigned long fd_flags, + unsigned long heap_flags) +{ + struct heap_helper_buffer *helper_buffer; + struct dma_buf *dmabuf; + int ret = -ENOMEM; + pgoff_t pg; + + helper_buffer = kzalloc(sizeof(*helper_buffer), GFP_KERNEL); + if (!helper_buffer) + return -ENOMEM; + + init_heap_helper_buffer(helper_buffer, system_heap_free); + helper_buffer->heap = heap; + helper_buffer->size = len; + + helper_buffer->pagecount = len / PAGE_SIZE; + helper_buffer->pages = kmalloc_array(helper_buffer->pagecount, + sizeof(*helper_buffer->pages), + GFP_KERNEL); + if (!helper_buffer->pages) { + ret = -ENOMEM; + goto err0; + } + + for (pg = 0; pg < helper_buffer->pagecount; pg++) { + /* + * Avoid trying to allocate memory if the process + * has been killed by by SIGKILL + */ + if (fatal_signal_pending(current)) + goto err1; + + helper_buffer->pages[pg] = alloc_page(GFP_KERNEL | __GFP_ZERO); + if (!helper_buffer->pages[pg]) + goto err1; + } + + /* create the dmabuf */ + dmabuf = heap_helper_export_dmabuf(helper_buffer, fd_flags); + if (IS_ERR(dmabuf)) { + ret = PTR_ERR(dmabuf); + goto err1; + } + + helper_buffer->dmabuf = dmabuf; + + ret = dma_buf_fd(dmabuf, fd_flags); + if (ret < 0) { + dma_buf_put(dmabuf); + /* just return, as put will call release and that will free */ + return ret; + } + + return ret; + +err1: + while (pg > 0) + __free_page(helper_buffer->pages[--pg]); + kfree(helper_buffer->pages); +err0: + kfree(helper_buffer); + + return ret; +} + +static const struct dma_heap_ops system_heap_ops = { + .allocate = system_heap_allocate, +}; + +static int system_heap_create(void) +{ + struct dma_heap_export_info exp_info; + int ret = 0; + + exp_info.name = "system"; + exp_info.ops = &system_heap_ops; + exp_info.priv = NULL; + + sys_heap = dma_heap_add(&exp_info); + if (IS_ERR(sys_heap)) + ret = PTR_ERR(sys_heap); + + return ret; +} +module_init(system_heap_create); +MODULE_LICENSE("GPL v2"); |