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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/dma-buf/heaps/cma_heap.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/dma-buf/heaps/cma_heap.c')
-rw-r--r--drivers/dma-buf/heaps/cma_heap.c407
1 files changed, 407 insertions, 0 deletions
diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_heap.c
new file mode 100644
index 000000000..28fb04ecc
--- /dev/null
+++ b/drivers/dma-buf/heaps/cma_heap.c
@@ -0,0 +1,407 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DMABUF CMA heap exporter
+ *
+ * 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/dma-buf.h>
+#include <linux/dma-heap.h>
+#include <linux/dma-map-ops.h>
+#include <linux/err.h>
+#include <linux/highmem.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+
+struct cma_heap {
+ struct dma_heap *heap;
+ struct cma *cma;
+};
+
+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;
+ bool mapped;
+};
+
+static int cma_heap_attach(struct dma_buf *dmabuf,
+ struct dma_buf_attachment *attachment)
+{
+ struct cma_heap_buffer *buffer = dmabuf->priv;
+ struct dma_heap_attachment *a;
+ 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);
+ a->mapped = false;
+
+ 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);
+ a->mapped = true;
+ return table;
+}
+
+static void cma_heap_unmap_dma_buf(struct dma_buf_attachment *attachment,
+ struct sg_table *table,
+ enum dma_data_direction direction)
+{
+ struct dma_heap_attachment *a = attachment->priv;
+
+ a->mapped = false;
+ 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;
+
+ 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 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;
+
+ 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 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 iosys_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++;
+ iosys_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++;
+ iosys_map_set_vaddr(map, buffer->vaddr);
+out:
+ mutex_unlock(&buffer->lock);
+
+ return ret;
+}
+
+static void cma_heap_vunmap(struct dma_buf *dmabuf, struct iosys_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);
+ iosys_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;
+ }
+
+ /* free page list */
+ kfree(buffer->pages);
+ /* release memory */
+ cma_release(cma_heap->cma, buffer->cma_pages, buffer->pagecount);
+ kfree(buffer);
+}
+
+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 struct dma_buf *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 cma_heap_buffer *buffer;
+ DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+ size_t size = PAGE_ALIGN(len);
+ 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;
+
+ buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
+ if (!buffer)
+ return ERR_PTR(-ENOMEM);
+
+ 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, pagecount, align, false);
+ if (!cma_pages)
+ goto free_buffer;
+
+ /* Clear the cma pages */
+ if (PageHighMem(cma_pages)) {
+ unsigned long nr_clear_pages = pagecount;
+ 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);
+ }
+
+ buffer->pages = kmalloc_array(pagecount, sizeof(*buffer->pages), GFP_KERNEL);
+ if (!buffer->pages) {
+ ret = -ENOMEM;
+ goto free_cma;
+ }
+
+ 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 */
+ exp_info.exp_name = dma_heap_get_name(heap);
+ 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;
+ }
+ return dmabuf;
+
+free_pages:
+ kfree(buffer->pages);
+free_cma:
+ cma_release(cma_heap->cma, cma_pages, pagecount);
+free_buffer:
+ kfree(buffer);
+
+ return ERR_PTR(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");