On Fri, Aug 30, 2024 at 12:04 AM Jens Wiklander <jens.wiklander@xxxxxxxxxx> wrote: > > Add a Linaro restricted heap using the linaro,restricted-heap bindings > implemented based on the generic restricted heap. > > The bindings defines a range of physical restricted memory. The heap > manages this address range using genalloc. The allocated dma-buf file > descriptor can later be registered with the TEE subsystem for later use > via Trusted Applications in the secure world. > > Co-developed-by: Olivier Masse <olivier.masse@xxxxxxx> > Signed-off-by: Olivier Masse <olivier.masse@xxxxxxx> > Signed-off-by: Jens Wiklander <jens.wiklander@xxxxxxxxxx> > --- > drivers/dma-buf/heaps/Kconfig | 10 ++ > drivers/dma-buf/heaps/Makefile | 1 + > .../dma-buf/heaps/restricted_heap_linaro.c | 165 ++++++++++++++++++ > 3 files changed, 176 insertions(+) > create mode 100644 drivers/dma-buf/heaps/restricted_heap_linaro.c > > diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig > index 58903bc62ac8..82e2c5d09242 100644 > --- a/drivers/dma-buf/heaps/Kconfig > +++ b/drivers/dma-buf/heaps/Kconfig > @@ -28,3 +28,13 @@ config DMABUF_HEAPS_RESTRICTED_MTK > help > Enable restricted dma-buf heaps for MediaTek platform. This heap is backed by > TEE client interfaces. If in doubt, say N. > + > +config DMABUF_HEAPS_RESTRICTED_LINARO > + bool "Linaro DMA-BUF Restricted Heap" > + depends on DMABUF_HEAPS_RESTRICTED > + help > + Choose this option to enable the Linaro restricted dma-buf heap. > + The restricted heap pools are defined according to the DT. Heaps > + are allocated in the pools using gen allocater. > + If in doubt, say N. > + > diff --git a/drivers/dma-buf/heaps/Makefile b/drivers/dma-buf/heaps/Makefile > index 0028aa9d875f..66b2f67c47b5 100644 > --- a/drivers/dma-buf/heaps/Makefile > +++ b/drivers/dma-buf/heaps/Makefile > @@ -2,4 +2,5 @@ > obj-$(CONFIG_DMABUF_HEAPS_CMA) += cma_heap.o > obj-$(CONFIG_DMABUF_HEAPS_RESTRICTED) += restricted_heap.o > obj-$(CONFIG_DMABUF_HEAPS_RESTRICTED_MTK) += restricted_heap_mtk.o > +obj-$(CONFIG_DMABUF_HEAPS_RESTRICTED_LINARO) += restricted_heap_linaro.o > obj-$(CONFIG_DMABUF_HEAPS_SYSTEM) += system_heap.o > diff --git a/drivers/dma-buf/heaps/restricted_heap_linaro.c b/drivers/dma-buf/heaps/restricted_heap_linaro.c > new file mode 100644 > index 000000000000..4b08ed514023 > --- /dev/null > +++ b/drivers/dma-buf/heaps/restricted_heap_linaro.c > @@ -0,0 +1,165 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * DMABUF secure heap exporter > + * > + * Copyright 2021 NXP. > + * Copyright 2024 Linaro Limited. > + */ > + > +#define pr_fmt(fmt) "rheap_linaro: " fmt > + > +#include <linux/dma-buf.h> > +#include <linux/err.h> > +#include <linux/genalloc.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 "restricted_heap.h" > + > +#define MAX_HEAP_COUNT 2 Are multiple supported because of what Cyrille mentioned here about permissions? https://lore.kernel.org/lkml/DBBPR04MB7514E006455AEA407041E4F788709@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ So this is just some arbitrary limit? I'd prefer to have some sort of documentation about this. > +#define HEAP_NAME_LEN 32 > + > +struct resmem_restricted { > + phys_addr_t base; > + phys_addr_t size; > + > + char name[HEAP_NAME_LEN]; > + > + bool no_map; > +}; > + > +static struct resmem_restricted restricted_data[MAX_HEAP_COUNT] = {0}; > +static unsigned int restricted_data_count; > + > +static int linaro_restricted_memory_allocate(struct restricted_heap *heap, > + struct restricted_buffer *buf) > +{ > + struct gen_pool *pool = heap->priv_data; > + unsigned long pa; > + int ret; > + > + buf->size = ALIGN(buf->size, PAGE_SIZE); > + pa = gen_pool_alloc(pool, buf->size); > + if (!pa) > + return -ENOMEM; > + > + ret = sg_alloc_table(&buf->sg_table, 1, GFP_KERNEL); > + if (ret) { > + gen_pool_free(pool, pa, buf->size); > + return ret; > + } > + > + sg_set_page(buf->sg_table.sgl, phys_to_page(pa), buf->size, 0); > + > + return 0; > +} > + > +static void linaro_restricted_memory_free(struct restricted_heap *heap, > + struct restricted_buffer *buf) > +{ > + struct gen_pool *pool = heap->priv_data; > + struct scatterlist *sg; > + unsigned int i; > + > + for_each_sg(buf->sg_table.sgl, sg, buf->sg_table.nents, i) > + gen_pool_free(pool, page_to_phys(sg_page(sg)), sg->length); > + sg_free_table(&buf->sg_table); > +} > + > +static const struct restricted_heap_ops linaro_restricted_heap_ops = { > + .alloc = linaro_restricted_memory_allocate, > + .free = linaro_restricted_memory_free, > +}; > + > +static int add_heap(struct resmem_restricted *mem) > +{ > + struct restricted_heap *heap; > + struct gen_pool *pool; > + int ret; > + > + if (mem->base == 0 || mem->size == 0) { > + pr_err("restricted_data base or size is not correct\n"); > + return -EINVAL; > + } > + > + heap = kzalloc(sizeof(*heap), GFP_KERNEL); > + if (!heap) > + return -ENOMEM; > + > + pool = gen_pool_create(PAGE_SHIFT, -1); > + if (!pool) { > + ret = -ENOMEM; > + goto err_free_heap; > + } > + > + ret = gen_pool_add(pool, mem->base, mem->size, -1); > + if (ret) > + goto err_free_pool; > + > + heap->no_map = mem->no_map; > + heap->priv_data = pool; > + heap->name = mem->name; > + heap->ops = &linaro_restricted_heap_ops; > + > + ret = restricted_heap_add(heap); > + if (ret) > + goto err_free_pool; > + > + return 0; > + > +err_free_pool: > + gen_pool_destroy(pool); > +err_free_heap: > + kfree(heap); > + > + return ret; > +} > + > +static int __init rmem_restricted_heap_setup(struct reserved_mem *rmem) > +{ > + size_t len = HEAP_NAME_LEN; > + const char *s; > + bool no_map; > + > + if (WARN_ONCE(restricted_data_count >= MAX_HEAP_COUNT, > + "Cannot handle more than %u restricted heaps\n", > + MAX_HEAP_COUNT)) > + return -EINVAL; > + > + no_map = of_get_flat_dt_prop(rmem->fdt_node, "no-map", NULL); > + s = strchr(rmem->name, '@'); > + if (s) > + len = umin(s - rmem->name + 1, len); > + > + restricted_data[restricted_data_count].base = rmem->base; > + restricted_data[restricted_data_count].size = rmem->size; > + restricted_data[restricted_data_count].no_map = no_map; > + strscpy(restricted_data[restricted_data_count].name, rmem->name, len); > + > + restricted_data_count++; > + return 0; > +} > + > +RESERVEDMEM_OF_DECLARE(linaro_restricted_heap, "linaro,restricted-heap", > + rmem_restricted_heap_setup); > + > +static int linaro_restricted_heap_init(void) > +{ > + unsigned int i; > + int ret; > + > + for (i = 0; i < restricted_data_count; i++) { > + ret = add_heap(&restricted_data[i]); > + if (ret) > + return ret; > + } > + return 0; > +} > + > +module_init(linaro_restricted_heap_init); > +MODULE_DESCRIPTION("Linaro Restricted Heap Driver"); > +MODULE_LICENSE("GPL"); > -- > 2.34.1 >