Hi Nicolas, Thanks for your comment, indeed these PR is linked to OPTEE OS. This one is using the same bindings to define the Secure Data Path reserved memory: https://github.com/OP-TEE/optee_os/commit/eb108a04369fbfaf60c03c0e00bbe9489a761c69 However, I'm not aware of another shared heap that could match our need. For information. it was previously done using ION heap: https://www.slideshare.net/linaroorg/bud17400-secure-data-path-with-optee Best regards, Olivier On mar., 2022-08-16 at 09:31 -0400, Nicolas Dufresne wrote: > Caution: EXT Email > > Hi, > > Le mardi 02 août 2022 à 11:58 +0200, Olivier Masse a écrit : > > add Linaro secure heap bindings: linaro,secure-heap > > Just a curiosity, how is this specific to Linaro OPTEE OS ? Shouldn't > it be "de- > linaro-ified" somehow ? > > regards, > Nicolas > > > use genalloc to allocate/free buffer from buffer pool. > > buffer pool info is from dts. > > use sg_table instore the allocated memory info, the length of > > sg_table is 1. > > implement secure_heap_buf_ops to implement buffer share in > > difference device: > > 1. Userspace passes this fd to all drivers it wants this buffer > > to share with: First the filedescriptor is converted to a &dma_buf > > using > > dma_buf_get(). Then the buffer is attached to the device using > > dma_buf_attach(). > > 2. Once the buffer is attached to all devices userspace can > > initiate DMA > > access to the shared buffer. In the kernel this is done by calling > > dma_buf_map_attachment() > > 3. get sg_table with dma_buf_map_attachment in difference device. > > > > Signed-off-by: Olivier Masse <olivier.masse@xxxxxxx> > > --- > > drivers/dma-buf/heaps/Kconfig | 21 +- > > drivers/dma-buf/heaps/Makefile | 1 + > > drivers/dma-buf/heaps/secure_heap.c | 588 > > ++++++++++++++++++++++++++++ > > 3 files changed, 606 insertions(+), 4 deletions(-) > > create mode 100644 drivers/dma-buf/heaps/secure_heap.c > > > > diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma- > > buf/heaps/Kconfig > > index 6a33193a7b3e..b2406932192e 100644 > > --- a/drivers/dma-buf/heaps/Kconfig > > +++ b/drivers/dma-buf/heaps/Kconfig > > @@ -1,8 +1,12 @@ > > -config DMABUF_HEAPS_DEFERRED_FREE > > - tristate > > +menuconfig DMABUF_HEAPS_DEFERRED_FREE > > + bool "DMA-BUF heaps deferred-free library" > > + help > > + Choose this option to enable the DMA-BUF heaps deferred- > > free library. > > > > -config DMABUF_HEAPS_PAGE_POOL > > - tristate > > +menuconfig DMABUF_HEAPS_PAGE_POOL > > + bool "DMA-BUF heaps page-pool library" > > + help > > + Choose this option to enable the DMA-BUF heaps page-pool > > library. > > > > config DMABUF_HEAPS_SYSTEM > > bool "DMA-BUF System Heap" > > @@ -26,3 +30,12 @@ config DMABUF_HEAPS_DSP > > Choose this option to enable the dsp dmabuf heap. The > > dsp heap > > is allocated by gen allocater. it's allocated according > > the dts. > > If in doubt, say Y. > > + > > +config DMABUF_HEAPS_SECURE > > + tristate "DMA-BUF Secure Heap" > > + depends on DMABUF_HEAPS && DMABUF_HEAPS_DEFERRED_FREE > > + help > > + Choose this option to enable the secure dmabuf heap. The > > secure heap > > + pools are defined according to the DT. Heaps are allocated > > + in the pools using gen allocater. > > + If in doubt, say Y. > > diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma- > > buf/heaps/Makefile > > index e70722ea615e..08f6aa5919d1 100644 > > --- a/drivers/dma-buf/heaps/Makefile > > +++ b/drivers/dma-buf/heaps/Makefile > > @@ -4,3 +4,4 @@ obj-$(CONFIG_DMABUF_HEAPS_PAGE_POOL) += > > page_pool.o > > obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o > > obj-$(CONFIG_DMABUF_HEAPS_CMA) += cma_heap.o > > obj-$(CONFIG_DMABUF_HEAPS_DSP) += dsp_heap.o > > +obj-$(CONFIG_DMABUF_HEAPS_SECURE) += secure_heap.o > > diff --git a/drivers/dma-buf/heaps/secure_heap.c b/drivers/dma- > > buf/heaps/secure_heap.c > > new file mode 100644 > > index 000000000000..31aac5d050b4 > > --- /dev/null > > +++ b/drivers/dma-buf/heaps/secure_heap.c > > @@ -0,0 +1,588 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * DMABUF secure heap exporter > > + * > > + * Copyright 2021 NXP. > > + */ > > + > > +#include <linux/dma-buf.h> > > +#include <linux/dma-heap.h> > > +#include <linux/dma-mapping.h> > > +#include <linux/err.h> > > +#include <linux/genalloc.h> > > +#include <linux/highmem.h> > > +#include <linux/mm.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/slab.h> > > +#include <linux/vmalloc.h> > > + > > +#include "deferred-free-helper.h" > > +#include "page_pool.h" > > + > > +#define MAX_SECURE_HEAP 2 > > +#define MAX_HEAP_NAME_LEN 32 > > + > > +struct secure_heap_buffer { > > + struct dma_heap *heap; > > + struct list_head attachments; > > + struct mutex lock; > > + unsigned long len; > > + struct sg_table sg_table; > > + int vmap_cnt; > > + struct deferred_freelist_item deferred_free; > > + void *vaddr; > > + bool uncached; > > +}; > > + > > +struct dma_heap_attachment { > > + struct device *dev; > > + struct sg_table *table; > > + struct list_head list; > > + bool no_map; > > + bool mapped; > > + bool uncached; > > +}; > > + > > +struct secure_heap_info { > > + struct gen_pool *pool; > > + > > + bool no_map; > > +}; > > + > > +struct rmem_secure { > > + phys_addr_t base; > > + phys_addr_t size; > > + > > + char name[MAX_HEAP_NAME_LEN]; > > + > > + bool no_map; > > +}; > > + > > +static struct rmem_secure secure_data[MAX_SECURE_HEAP] = {0}; > > +static unsigned int secure_data_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->dma_address = sg->dma_address; > > +#ifdef CONFIG_NEED_SG_DMA_LENGTH > > + new_sg->dma_length = sg->dma_length; > > +#endif > > + new_sg = sg_next(new_sg); > > + } > > + > > + return new_table; > > +} > > + > > +static int secure_heap_attach(struct dma_buf *dmabuf, > > + struct dma_buf_attachment *attachment) > > +{ > > + struct secure_heap_buffer *buffer = dmabuf->priv; > > + struct secure_heap_info *info = dma_heap_get_drvdata(buffer- > > >heap); > > + struct dma_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; > > + INIT_LIST_HEAD(&a->list); > > + a->no_map = info->no_map; > > + a->mapped = false; > > + a->uncached = buffer->uncached; > > + attachment->priv = a; > > + > > + mutex_lock(&buffer->lock); > > + list_add(&a->list, &buffer->attachments); > > + mutex_unlock(&buffer->lock); > > + > > + return 0; > > +} > > + > > +static void secure_heap_detach(struct dma_buf *dmabuf, > > + struct dma_buf_attachment *attachment) > > +{ > > + struct secure_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->table); > > + kfree(a); > > +} > > + > > +static struct sg_table *secure_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 attr = 0; > > + int ret; > > + > > + if (!a->no_map) { > > + if (a->uncached) > > + attr = DMA_ATTR_SKIP_CPU_SYNC; > > + > > + ret = dma_map_sgtable(attachment->dev, table, > > direction, attr); > > + if (ret) > > + return ERR_PTR(ret); > > + > > + a->mapped = true; > > + } > > + > > + return table; > > +} > > + > > +static void secure_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; > > + int attr = 0; > > + > > + if (!a->no_map) { > > + if (a->uncached) > > + attr = DMA_ATTR_SKIP_CPU_SYNC; > > + > > + a->mapped = false; > > + dma_unmap_sgtable(attachment->dev, table, direction, > > attr); > > + } > > +} > > + > > +static int secure_heap_dma_buf_begin_cpu_access(struct dma_buf > > *dmabuf, > > + enum > > dma_data_direction direction) > > +{ > > + struct secure_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); > > + > > + if (!buffer->uncached) { > > + 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 secure_heap_dma_buf_end_cpu_access(struct dma_buf > > *dmabuf, > > + enum dma_data_direction > > direction) > > +{ > > + struct secure_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); > > + > > + if (!buffer->uncached) { > > + 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 secure_heap_mmap(struct dma_buf *dmabuf, struct > > vm_area_struct *vma) > > +{ > > + struct secure_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; > > + > > + if (buffer->uncached) > > + vma->vm_page_prot = pgprot_writecombine(vma- > > >vm_page_prot); > > + > > + 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; > > + } > > + return 0; > > +} > > + > > +static void *secure_heap_do_vmap(struct secure_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; > > + pgprot_t pgprot = PAGE_KERNEL; > > + void *vaddr; > > + > > + if (!pages) > > + return ERR_PTR(-ENOMEM); > > + > > + if (buffer->uncached) > > + pgprot = pgprot_writecombine(PAGE_KERNEL); > > + > > + for_each_sgtable_page(table, &piter, 0) { > > + WARN_ON(tmp - pages >= npages); > > + *tmp++ = sg_page_iter_page(&piter); > > + } > > + > > + vaddr = vmap(pages, npages, VM_MAP, pgprot); > > + vfree(pages); > > + > > + if (!vaddr) > > + return ERR_PTR(-ENOMEM); > > + > > + return vaddr; > > +} > > + > > +static int secure_heap_vmap(struct dma_buf *dmabuf, struct > > dma_buf_map *map) > > +{ > > + struct secure_heap_buffer *buffer = dmabuf->priv; > > + void *vaddr; > > + int ret = 0; > > + > > + mutex_lock(&buffer->lock); > > + if (buffer->vmap_cnt) { > > + buffer->vmap_cnt++; > > + goto out; > > + } > > + > > + vaddr = secure_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 secure_heap_vunmap(struct dma_buf *dmabuf, struct > > dma_buf_map *map) > > +{ > > + struct secure_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 secure_heap_zero_buffer(struct secure_heap_buffer > > *buffer) > > +{ > > + struct sg_table *sgt = &buffer->sg_table; > > + struct sg_page_iter piter; > > + struct page *p; > > + void *vaddr; > > + > > + for_each_sgtable_page(sgt, &piter, 0) { > > + p = sg_page_iter_page(&piter); > > + vaddr = kmap_atomic(p); > > + memset(vaddr, 0, PAGE_SIZE); > > + kunmap_atomic(vaddr); > > + } > > +} > > + > > +static void secure_heap_buf_free(struct deferred_freelist_item > > *item, > > + enum df_reason reason) > > +{ > > + struct secure_heap_buffer *buffer; > > + struct secure_heap_info *info; > > + struct sg_table *table; > > + struct scatterlist *sg; > > + int i; > > + > > + buffer = container_of(item, struct secure_heap_buffer, > > deferred_free); > > + info = dma_heap_get_drvdata(buffer->heap); > > + > > + if (!info->no_map) { > > + // Zero the buffer pages before adding back to the > > pool > > + if (reason == DF_NORMAL) > > + secure_heap_zero_buffer(buffer); > > + } > > + > > + table = &buffer->sg_table; > > + for_each_sg(table->sgl, sg, table->nents, i) > > + gen_pool_free(info->pool, sg_dma_address(sg), > > sg_dma_len(sg)); > > + > > + sg_free_table(table); > > + kfree(buffer); > > +} > > + > > +static void secure_heap_dma_buf_release(struct dma_buf *dmabuf) > > +{ > > + struct secure_heap_buffer *buffer = dmabuf->priv; > > + int npages = PAGE_ALIGN(buffer->len) / PAGE_SIZE; > > + > > + deferred_free(&buffer->deferred_free, secure_heap_buf_free, > > npages); > > +} > > + > > +static const struct dma_buf_ops secure_heap_buf_ops = { > > + .attach = secure_heap_attach, > > + .detach = secure_heap_detach, > > + .map_dma_buf = secure_heap_map_dma_buf, > > + .unmap_dma_buf = secure_heap_unmap_dma_buf, > > + .begin_cpu_access = secure_heap_dma_buf_begin_cpu_access, > > + .end_cpu_access = secure_heap_dma_buf_end_cpu_access, > > + .mmap = secure_heap_mmap, > > + .vmap = secure_heap_vmap, > > + .vunmap = secure_heap_vunmap, > > + .release = secure_heap_dma_buf_release, > > +}; > > + > > +static struct dma_buf *secure_heap_do_allocate(struct dma_heap > > *heap, > > + unsigned long len, > > + unsigned long > > fd_flags, > > + unsigned long > > heap_flags, > > + bool uncached) > > +{ > > + struct secure_heap_buffer *buffer; > > + struct secure_heap_info *info = dma_heap_get_drvdata(heap); > > + DEFINE_DMA_BUF_EXPORT_INFO(exp_info); > > + unsigned long size = roundup(len, PAGE_SIZE); > > + struct dma_buf *dmabuf; > > + struct sg_table *table; > > + int ret = -ENOMEM; > > + unsigned long phy_addr; > > + > > + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); > > + if (!buffer) > > + return ERR_PTR(-ENOMEM); > > + > > + INIT_LIST_HEAD(&buffer->attachments); > > + mutex_init(&buffer->lock); > > + buffer->heap = heap; > > + buffer->len = size; > > + buffer->uncached = uncached; > > + > > + phy_addr = gen_pool_alloc(info->pool, size); > > + if (!phy_addr) > > + goto free_buffer; > > + > > + table = &buffer->sg_table; > > + if (sg_alloc_table(table, 1, GFP_KERNEL)) > > + goto free_pool; > > + > > + sg_set_page(table->sgl, phys_to_page(phy_addr), size, 0); > > + sg_dma_address(table->sgl) = phy_addr; > > + sg_dma_len(table->sgl) = size; > > + > > + /* create the dmabuf */ > > + exp_info.exp_name = dma_heap_get_name(heap); > > + exp_info.ops = &secure_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: > > + sg_free_table(table); > > + > > +free_pool: > > + gen_pool_free(info->pool, phy_addr, size); > > + > > +free_buffer: > > + mutex_destroy(&buffer->lock); > > + kfree(buffer); > > + > > + return ERR_PTR(ret); > > +} > > + > > +static struct dma_buf *secure_heap_allocate(struct dma_heap *heap, > > + unsigned long len, > > + unsigned long fd_flags, > > + unsigned long heap_flags) > > +{ > > + // use uncache buffer here by default > > + return secure_heap_do_allocate(heap, len, fd_flags, > > heap_flags, true); > > + // use cache buffer > > + // return secure_heap_do_allocate(heap, len, fd_flags, > > heap_flags, false); > > +} > > + > > +static const struct dma_heap_ops secure_heap_ops = { > > + .allocate = secure_heap_allocate, > > +}; > > + > > +static int secure_heap_add(struct rmem_secure *rmem) > > +{ > > + struct dma_heap *secure_heap; > > + struct dma_heap_export_info exp_info; > > + struct secure_heap_info *info = NULL; > > + struct gen_pool *pool = NULL; > > + int ret = -EINVAL; > > + > > + if (rmem->base == 0 || rmem->size == 0) { > > + pr_err("secure_data base or size is not correct\n"); > > + goto error; > > + } > > + > > + info = kzalloc(sizeof(*info), GFP_KERNEL); > > + if (!info) { > > + pr_err("dmabuf info allocation failed\n"); > > + ret = -ENOMEM; > > + goto error; > > + } > > + > > + pool = gen_pool_create(PAGE_SHIFT, -1); > > + if (!pool) { > > + pr_err("can't create gen pool\n"); > > + ret = -ENOMEM; > > + goto error; > > + } > > + > > + if (gen_pool_add(pool, rmem->base, rmem->size, -1) < 0) { > > + pr_err("failed to add memory into pool\n"); > > + ret = -ENOMEM; > > + goto error; > > + } > > + > > + info->pool = pool; > > + info->no_map = rmem->no_map; > > + > > + exp_info.name = rmem->name; > > + exp_info.ops = &secure_heap_ops; > > + exp_info.priv = info; > > + > > + secure_heap = dma_heap_add(&exp_info); > > + if (IS_ERR(secure_heap)) { > > + pr_err("dmabuf secure heap allocation failed\n"); > > + ret = PTR_ERR(secure_heap); > > + goto error; > > + } > > + > > + return 0; > > + > > +error: > > + kfree(info); > > + if (pool) > > + gen_pool_destroy(pool); > > + > > + return ret; > > +} > > + > > +static int secure_heap_create(void) > > +{ > > + unsigned int i; > > + int ret; > > + > > + for (i = 0; i < secure_data_count; i++) { > > + ret = secure_heap_add(&secure_data[i]); > > + if (ret) > > + return ret; > > + } > > + return 0; > > +} > > + > > +static int rmem_secure_heap_device_init(struct reserved_mem *rmem, > > + struct device *dev) > > +{ > > + dev_set_drvdata(dev, rmem); > > + return 0; > > +} > > + > > +static void rmem_secure_heap_device_release(struct reserved_mem > > *rmem, > > + struct device *dev) > > +{ > > + dev_set_drvdata(dev, NULL); > > +} > > + > > +static const struct reserved_mem_ops rmem_dma_ops = { > > + .device_init = rmem_secure_heap_device_init, > > + .device_release = rmem_secure_heap_device_release, > > +}; > > + > > +static int __init rmem_secure_heap_setup(struct reserved_mem > > *rmem) > > +{ > > + if (secure_data_count < MAX_SECURE_HEAP) { > > + int name_len = 0; > > + char *s = rmem->name; > > + > > + secure_data[secure_data_count].base = rmem->base; > > + secure_data[secure_data_count].size = rmem->size; > > + secure_data[secure_data_count].no_map = > > + (of_get_flat_dt_prop(rmem->fdt_node, "no- > > map", NULL) != NULL); > > + > > + while (name_len < MAX_HEAP_NAME_LEN) { > > + if ((*s == '@') || (*s == '\0')) > > + break; > > + name_len++; > > + s++; > > + } > > + if (name_len == MAX_HEAP_NAME_LEN) > > + name_len--; > > + > > + strncpy(secure_data[secure_data_count].name, rmem- > > >name, name_len); > > + > > + rmem->ops = &rmem_dma_ops; > > + pr_info("Reserved memory: DMA buf secure pool %s at > > %pa, size %ld MiB\n", > > + secure_data[secure_data_count].name, > > + &rmem->base, (unsigned long)rmem->size / > > SZ_1M); > > + > > + secure_data_count++; > > + return 0; > > + } > > + WARN_ONCE(1, "Cannot handle more than %u secure heaps\n", > > MAX_SECURE_HEAP); > > + return -EINVAL; > > +} > > + > > +RESERVEDMEM_OF_DECLARE(secure_heap, "linaro,secure-heap", > > rmem_secure_heap_setup); > > + > > +module_init(secure_heap_create); > > +MODULE_LICENSE("GPL v2"); > >
