From: Hyesoo Yu <hyesoo...@samsung.com> This patch supports chunk heap that allocates the buffers that arranged into a list a fixed size chunks taken from CMA.
The chunk heap driver is bound directly to a reserved_memory node by following Rob Herring's suggestion in [1]. [1] https://lore.kernel.org/lkml/20191025225009.50305-2-john.stu...@linaro.org/T/#m3dc63acd33fea269a584f43bb799a876f0b2b45d Signed-off-by: Hyesoo Yu <hyesoo...@samsung.com> Signed-off-by: Hridya Valsaraju <hri...@google.com> Signed-off-by: Minchan Kim <minc...@kernel.org> --- drivers/dma-buf/heaps/Kconfig | 8 + drivers/dma-buf/heaps/Makefile | 1 + drivers/dma-buf/heaps/chunk_heap.c | 477 +++++++++++++++++++++++++++++ 3 files changed, 486 insertions(+) create mode 100644 drivers/dma-buf/heaps/chunk_heap.c diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig index a5eef06c4226..6527233f52a8 100644 --- a/drivers/dma-buf/heaps/Kconfig +++ b/drivers/dma-buf/heaps/Kconfig @@ -12,3 +12,11 @@ config DMABUF_HEAPS_CMA 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. + +config DMABUF_HEAPS_CHUNK + bool "DMA-BUF CHUNK Heap" + depends on DMABUF_HEAPS && DMA_CMA + help + Choose this option to enable dma-buf CHUNK heap. This heap is backed + by the Contiguous Memory Allocator (CMA) and allocates the buffers that + arranged into a list of fixed size chunks taken from CMA. diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile index 974467791032..8faa6cfdc0c5 100644 --- a/drivers/dma-buf/heaps/Makefile +++ b/drivers/dma-buf/heaps/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o obj-$(CONFIG_DMABUF_HEAPS_CMA) += cma_heap.o +obj-$(CONFIG_DMABUF_HEAPS_CHUNK) += chunk_heap.o diff --git a/drivers/dma-buf/heaps/chunk_heap.c b/drivers/dma-buf/heaps/chunk_heap.c new file mode 100644 index 000000000000..64f748c81e1f --- /dev/null +++ b/drivers/dma-buf/heaps/chunk_heap.c @@ -0,0 +1,477 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMA-BUF chunk heap exporter + * + * Copyright (c) 2020 Samsung Electronics Co., Ltd. + * Author: <hyesoo...@samsung.com> for Samsung Electronics. + */ + +#include <linux/cma.h> +#include <linux/device.h> +#include <linux/dma-buf.h> +#include <linux/dma-heap.h> +#include <linux/dma-mapping.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/of.h> +#include <linux/of_fdt.h> +#include <linux/of_reserved_mem.h> +#include <linux/scatterlist.h> +#include <linux/sched/signal.h> +#include <linux/slab.h> + +struct chunk_heap { + struct dma_heap *heap; + uint32_t order; + struct cma *cma; +}; + +struct chunk_heap_buffer { + struct chunk_heap *heap; + struct list_head attachments; + struct mutex lock; + struct sg_table sg_table; + unsigned long len; + int vmap_cnt; + void *vaddr; +}; + +struct chunk_heap_attachment { + struct device *dev; + struct sg_table *table; + struct list_head list; + bool mapped; +}; + +struct chunk_heap chunk_heaps[MAX_CMA_AREAS]; +unsigned int chunk_heap_count; + +static struct sg_table *dup_sg_table(struct sg_table *table) +{ + struct sg_table *new_table; + int ret, i; + struct scatterlist *sg, *new_sg; + + new_table = kzalloc(sizeof(*new_table), GFP_KERNEL); + if (!new_table) + return ERR_PTR(-ENOMEM); + + ret = sg_alloc_table(new_table, table->orig_nents, GFP_KERNEL); + if (ret) { + kfree(new_table); + return ERR_PTR(-ENOMEM); + } + + new_sg = new_table->sgl; + for_each_sgtable_sg(table, sg, i) { + sg_set_page(new_sg, sg_page(sg), sg->length, sg->offset); + new_sg = sg_next(new_sg); + } + + return new_table; +} + +static int chunk_heap_attach(struct dma_buf *dmabuf, struct dma_buf_attachment *attachment) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + struct chunk_heap_attachment *a; + struct sg_table *table; + + a = kzalloc(sizeof(*a), GFP_KERNEL); + if (!a) + return -ENOMEM; + + table = dup_sg_table(&buffer->sg_table); + if (IS_ERR(table)) { + kfree(a); + return -ENOMEM; + } + + a->table = table; + a->dev = attachment->dev; + + attachment->priv = a; + + mutex_lock(&buffer->lock); + list_add(&a->list, &buffer->attachments); + mutex_unlock(&buffer->lock); + + return 0; +} + +static void chunk_heap_detach(struct dma_buf *dmabuf, struct dma_buf_attachment *attachment) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + struct chunk_heap_attachment *a = attachment->priv; + + mutex_lock(&buffer->lock); + list_del(&a->list); + mutex_unlock(&buffer->lock); + + sg_free_table(a->table); + kfree(a->table); + kfree(a); +} + +static struct sg_table *chunk_heap_map_dma_buf(struct dma_buf_attachment *attachment, + enum dma_data_direction direction) +{ + struct chunk_heap_attachment *a = attachment->priv; + struct sg_table *table = a->table; + int ret; + + if (a->mapped) + return table; + + ret = dma_map_sgtable(attachment->dev, table, direction, 0); + if (ret) + return ERR_PTR(ret); + + a->mapped = true; + return table; +} + +static void chunk_heap_unmap_dma_buf(struct dma_buf_attachment *attachment, + struct sg_table *table, + enum dma_data_direction direction) +{ + struct chunk_heap_attachment *a = attachment->priv; + + a->mapped = false; + dma_unmap_sgtable(attachment->dev, table, direction, 0); +} + +static int chunk_heap_dma_buf_begin_cpu_access(struct dma_buf *dmabuf, + enum dma_data_direction direction) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + struct chunk_heap_attachment *a; + + mutex_lock(&buffer->lock); + + if (buffer->vmap_cnt) + invalidate_kernel_vmap_range(buffer->vaddr, buffer->len); + + list_for_each_entry(a, &buffer->attachments, list) { + if (!a->mapped) + continue; + dma_sync_sgtable_for_cpu(a->dev, a->table, direction); + } + mutex_unlock(&buffer->lock); + + return 0; +} + +static int chunk_heap_dma_buf_end_cpu_access(struct dma_buf *dmabuf, + enum dma_data_direction direction) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + struct chunk_heap_attachment *a; + + mutex_lock(&buffer->lock); + + if (buffer->vmap_cnt) + flush_kernel_vmap_range(buffer->vaddr, buffer->len); + + list_for_each_entry(a, &buffer->attachments, list) { + if (!a->mapped) + continue; + dma_sync_sgtable_for_device(a->dev, a->table, direction); + } + mutex_unlock(&buffer->lock); + + return 0; +} + +static int chunk_heap_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + struct sg_table *table = &buffer->sg_table; + unsigned long addr = vma->vm_start; + struct sg_page_iter piter; + int ret; + + for_each_sgtable_page(table, &piter, vma->vm_pgoff) { + struct page *page = sg_page_iter_page(&piter); + + ret = remap_pfn_range(vma, addr, page_to_pfn(page), PAGE_SIZE, + vma->vm_page_prot); + if (ret) + return ret; + addr += PAGE_SIZE; + if (addr >= vma->vm_end) + return 0; + } + return 0; +} + +static void *chunk_heap_do_vmap(struct chunk_heap_buffer *buffer) +{ + struct sg_table *table = &buffer->sg_table; + int npages = PAGE_ALIGN(buffer->len) / PAGE_SIZE; + struct page **pages = vmalloc(sizeof(struct page *) * npages); + struct page **tmp = pages; + struct sg_page_iter piter; + void *vaddr; + + if (!pages) + return ERR_PTR(-ENOMEM); + + for_each_sgtable_page(table, &piter, 0) { + WARN_ON(tmp - pages >= npages); + *tmp++ = sg_page_iter_page(&piter); + } + + vaddr = vmap(pages, npages, VM_MAP, PAGE_KERNEL); + vfree(pages); + + if (!vaddr) + return ERR_PTR(-ENOMEM); + + return vaddr; +} + +static int chunk_heap_vmap(struct dma_buf *dmabuf, struct dma_buf_map *map) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + void *vaddr; + + mutex_lock(&buffer->lock); + if (buffer->vmap_cnt) { + vaddr = buffer->vaddr; + } else { + vaddr = chunk_heap_do_vmap(buffer); + if (IS_ERR(vaddr)) { + mutex_unlock(&buffer->lock); + + return PTR_ERR(vaddr); + } + buffer->vaddr = vaddr; + } + buffer->vmap_cnt++; + dma_buf_map_set_vaddr(map, vaddr); + + mutex_unlock(&buffer->lock); + + return 0; +} + +static void chunk_heap_vunmap(struct dma_buf *dmabuf, struct dma_buf_map *map) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + + mutex_lock(&buffer->lock); + if (!--buffer->vmap_cnt) { + vunmap(buffer->vaddr); + buffer->vaddr = NULL; + } + mutex_unlock(&buffer->lock); +} + +static void chunk_heap_dma_buf_release(struct dma_buf *dmabuf) +{ + struct chunk_heap_buffer *buffer = dmabuf->priv; + struct chunk_heap *chunk_heap = buffer->heap; + struct sg_table *table; + struct scatterlist *sg; + int i; + + table = &buffer->sg_table; + for_each_sgtable_sg(table, sg, i) + cma_release(chunk_heap->cma, sg_page(sg), 1 << chunk_heap->order); + sg_free_table(table); + kfree(buffer); +} + +static const struct dma_buf_ops chunk_heap_buf_ops = { + .attach = chunk_heap_attach, + .detach = chunk_heap_detach, + .map_dma_buf = chunk_heap_map_dma_buf, + .unmap_dma_buf = chunk_heap_unmap_dma_buf, + .begin_cpu_access = chunk_heap_dma_buf_begin_cpu_access, + .end_cpu_access = chunk_heap_dma_buf_end_cpu_access, + .mmap = chunk_heap_mmap, + .vmap = chunk_heap_vmap, + .vunmap = chunk_heap_vunmap, + .release = chunk_heap_dma_buf_release, +}; + +static int chunk_heap_allocate(struct dma_heap *heap, unsigned long len, + unsigned long fd_flags, unsigned long heap_flags) +{ + struct chunk_heap *chunk_heap = dma_heap_get_drvdata(heap); + struct chunk_heap_buffer *buffer; + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); + struct dma_buf *dmabuf; + struct sg_table *table; + struct scatterlist *sg; + struct page **pages; + unsigned int chunk_size = PAGE_SIZE << chunk_heap->order; + unsigned int count, alloced = 0; + unsigned int alloc_order = max_t(unsigned int, pageblock_order, chunk_heap->order); + unsigned int nr_chunks_per_alloc = 1 << (alloc_order - chunk_heap->order); + gfp_t gfp_flags = GFP_KERNEL|__GFP_NORETRY; + int ret = -ENOMEM; + pgoff_t pg; + + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); + if (!buffer) + return ret; + + INIT_LIST_HEAD(&buffer->attachments); + mutex_init(&buffer->lock); + buffer->heap = chunk_heap; + buffer->len = ALIGN(len, chunk_size); + count = buffer->len / chunk_size; + + pages = kvmalloc_array(count, sizeof(*pages), GFP_KERNEL); + if (!pages) + goto err_pages; + + while (alloced < count) { + struct page *page; + int i; + + while (count - alloced < nr_chunks_per_alloc) { + alloc_order--; + nr_chunks_per_alloc >>= 1; + } + + page = cma_alloc(chunk_heap->cma, 1 << alloc_order, + alloc_order, gfp_flags); + if (!page) { + if (gfp_flags & __GFP_NORETRY) { + gfp_flags &= ~__GFP_NORETRY; + continue; + } + break; + } + + for (i = 0; i < nr_chunks_per_alloc; i++, alloced++) { + pages[alloced] = page; + page += 1 << chunk_heap->order; + } + } + + if (alloced < count) + goto err_alloc; + + table = &buffer->sg_table; + if (sg_alloc_table(table, count, GFP_KERNEL)) + goto err_alloc; + + sg = table->sgl; + for (pg = 0; pg < count; pg++) { + sg_set_page(sg, pages[pg], chunk_size, 0); + sg = sg_next(sg); + } + + exp_info.ops = &chunk_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 err_export; + } + kvfree(pages); + + ret = dma_buf_fd(dmabuf, fd_flags); + if (ret < 0) { + dma_buf_put(dmabuf); + return ret; + } + + return 0; +err_export: + sg_free_table(table); +err_alloc: + for (pg = 0; pg < alloced; pg++) + cma_release(chunk_heap->cma, pages[pg], 1 << chunk_heap->order); + kvfree(pages); +err_pages: + kfree(buffer); + + return ret; +} + +static const struct dma_heap_ops chunk_heap_ops = { + .allocate = chunk_heap_allocate, +}; + +static int register_chunk_heap(struct chunk_heap *chunk_heap_info) +{ + struct dma_heap_export_info exp_info; + + exp_info.name = cma_get_name(chunk_heap_info->cma); + exp_info.ops = &chunk_heap_ops; + exp_info.priv = chunk_heap_info; + + chunk_heap_info->heap = dma_heap_add(&exp_info); + if (IS_ERR(chunk_heap_info->heap)) + return PTR_ERR(chunk_heap_info->heap); + + return 0; +} + +static int __init chunk_heap_init(void) +{ + unsigned int i; + + for (i = 0; i < chunk_heap_count; i++) + register_chunk_heap(&chunk_heaps[i]); + + return 0; +} +module_init(chunk_heap_init); + +#ifdef CONFIG_OF_EARLY_FLATTREE + +static int __init dmabuf_chunk_heap_area_init(struct reserved_mem *rmem) +{ + int ret; + struct cma *cma; + struct chunk_heap *chunk_heap_info; + const __be32 *chunk_order; + + phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); + phys_addr_t mask = align - 1; + + if ((rmem->base & mask) || (rmem->size & mask)) { + pr_err("Incorrect alignment for CMA region\n"); + return -EINVAL; + } + + ret = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name, &cma); + if (ret) { + pr_err("Reserved memory: unable to setup CMA region\n"); + return ret; + } + + /* Architecture specific contiguous memory fixup. */ + dma_contiguous_early_fixup(rmem->base, rmem->size); + + chunk_heap_info = &chunk_heaps[chunk_heap_count]; + chunk_heap_info->cma = cma; + + chunk_order = of_get_flat_dt_prop(rmem->fdt_node, "chunk-order", NULL); + + if (chunk_order) + chunk_heap_info->order = be32_to_cpu(*chunk_order); + else + chunk_heap_info->order = 4; + + chunk_heap_count++; + + return 0; +} +RESERVEDMEM_OF_DECLARE(dmabuf_chunk_heap, "dma_heap,chunk", + dmabuf_chunk_heap_area_init); +#endif + +MODULE_DESCRIPTION("DMA-BUF Chunk Heap"); +MODULE_LICENSE("GPL v2"); -- 2.30.0.284.gd98b1dd5eaa7-goog
