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Commit 0870b455 authored by Patrick Daly's avatar Patrick Daly Committed by Liam Mark
Browse files

secure_buffer: Remove all-in-one buffer usage 



Allocate objects via kzalloc() when possible. For the case where a large
chunk (512 Kb) of physically contiguous memory is required, continue to use
a special purpose buffer reserved at boot. Since this special purpose
buffer is no longer used for random metadata, the associated code is
simpler to understand.

Change-Id: I85078f351293b556a501e9aca075ef87e2e86afd
Signed-off-by: default avatarPatrick Daly <pdaly@codeaurora.org>
parent 57117681

drivers/soc/qcom/secure_buffer.c

+72 −67
Original line number Diff line number Diff line
@@ -43,11 +43,6 @@ struct mem_prot_info { 
	u64 size;

};



struct info_list {

	struct mem_prot_info *list_head;

	u64 list_size;

};



#define MEM_PROT_ASSIGN_ID		0x16

#define MEM_PROTECT_LOCK_ID2		0x0A

#define MEM_PROTECT_LOCK_ID2_FLAT	0x11
@@ -61,14 +56,8 @@ struct dest_vm_and_perm_info { 
	u32 ctx_size;

};



struct dest_info_list {

	struct dest_vm_and_perm_info *dest_info;

	u64 list_size;

};



static void *qcom_secure_mem;

#define QCOM_SECURE_MEM_SIZE (512*1024)

#define PADDING 32



static int secure_buffer_change_chunk(u32 chunks,

				u32 nchunks,
@@ -201,14 +190,22 @@ int msm_unsecure_table(struct sg_table *table) 


}



static void populate_dest_info(int *dest_vmids, int nelements,

			int *dest_perms, struct dest_info_list **list,

			void *current_qcom_secure_mem)

static struct dest_vm_and_perm_info *

populate_dest_info(int *dest_vmids, int nelements, int *dest_perms,

		   size_t *size_in_bytes)

{

	struct dest_vm_and_perm_info *dest_info;

	int i;

	size_t size;



	dest_info = (struct dest_vm_and_perm_info *)current_qcom_secure_mem;

	/* Ensure allocated size is less than PAGE_ALLOC_COSTLY_ORDER */

	size = nelements * sizeof(*dest_info);

	if (size > PAGE_SIZE)

		return NULL;



	dest_info = kzalloc(size, GFP_KERNEL);

	if (!dest_info)

		return NULL;



	for (i = 0; i < nelements; i++) {

		dest_info[i].vm = dest_vmids[i];
@@ -217,30 +214,43 @@ static void populate_dest_info(int *dest_vmids, int nelements, 
		dest_info[i].ctx_size = 0;

	}



	*list = (struct dest_info_list *)&dest_info[i];



	(*list)->dest_info = dest_info;

	(*list)->list_size = nelements * sizeof(struct dest_vm_and_perm_info);

	*size_in_bytes = size;

	return dest_info;

}



static void get_info_list_from_table(struct sg_table *table,

					struct info_list **list)

/* Must hold secure_buffer_mutex while allocated buffer is in use */

static struct mem_prot_info *get_info_list_from_table(struct sg_table *table,

						      size_t *size_in_bytes)

{

	int i;

	struct scatterlist *sg;

	struct mem_prot_info *info;

	size_t size;



	info = (struct mem_prot_info *)qcom_secure_mem;

	size = table->nents * sizeof(*info);



	if (size >= QCOM_SECURE_MEM_SIZE) {

		pr_err("%s: Not enough memory allocated. Required size %zd\n",

				__func__, size);

		return NULL;

	}



	if (!qcom_secure_mem) {

		pr_err("%s is not functional as qcom_secure_mem is not allocated.\n",

				__func__);

		return NULL;

	}



	/* "Allocate" it */

	info = qcom_secure_mem;



	for_each_sg(table->sgl, sg, table->nents, i) {

		info[i].addr = page_to_phys(sg_page(sg));

		info[i].size = sg->length;

	}



	*list = (struct info_list *)&(info[i]);



	(*list)->list_head = info;

	(*list)->list_size = table->nents * sizeof(struct mem_prot_info);

	*size_in_bytes = size;

	return info;

}



int hyp_assign_table(struct sg_table *table,
@@ -249,66 +259,58 @@ int hyp_assign_table(struct sg_table *table, 
			int dest_nelems)

{

	int ret;

	struct info_list *info_list = NULL;

	struct dest_info_list *dest_info_list = NULL;

	struct scm_desc desc = {0};

	u32 *source_vm_copy;

	void *current_qcom_secure_mem;



	size_t reqd_size = dest_nelems * sizeof(struct dest_vm_and_perm_info) +

			table->nents * sizeof(struct mem_prot_info) +

			sizeof(dest_info_list) + sizeof(info_list) + PADDING;



	if (!qcom_secure_mem) {

		pr_err("%s is not functional as qcom_secure_mem is not allocated.\n",

				__func__);

		return -ENOMEM;

	}



	if (reqd_size > QCOM_SECURE_MEM_SIZE) {

		pr_err("%s: Not enough memory allocated. Required size %zd\n",

				__func__, reqd_size);

		return -EINVAL;

	}

	size_t source_vm_copy_size;

	struct dest_vm_and_perm_info *dest_vm_copy;

	size_t dest_vm_copy_size;

	struct mem_prot_info *sg_table_copy;

	size_t sg_table_copy_size;



	/*

	 * We can only pass cache-aligned sizes to hypervisor, so we need

	 * to kmalloc and memcpy the source_vm_list here.

	 */

	source_vm_copy = kmalloc_array(

		source_nelems, sizeof(*source_vm_copy), GFP_KERNEL);

	if (!source_vm_copy) {

	source_vm_copy_size = sizeof(*source_vm_copy) * source_nelems;

	source_vm_copy = kzalloc(source_vm_copy_size, GFP_KERNEL);

	if (!source_vm_copy)

		return -ENOMEM;

	}



	memcpy(source_vm_copy, source_vm_list,

	       sizeof(*source_vm_list) * source_nelems);

	memcpy(source_vm_copy, source_vm_list, source_vm_copy_size);



	mutex_lock(&secure_buffer_mutex);



	get_info_list_from_table(table, &info_list);

	dest_vm_copy = populate_dest_info(dest_vmids, dest_nelems, dest_perms,

					  &dest_vm_copy_size);

	if (!dest_vm_copy) {

		ret = -ENOMEM;

		goto out_free;

	}



	mutex_lock(&secure_buffer_mutex);



	current_qcom_secure_mem = &(info_list[1]);

	populate_dest_info(dest_vmids, dest_nelems, dest_perms,

				&dest_info_list, current_qcom_secure_mem);

	sg_table_copy = get_info_list_from_table(table, &sg_table_copy_size);

	if (!sg_table_copy) {

		ret = -ENOMEM;

		goto out_unlock;

	}



	desc.args[0] = virt_to_phys(info_list->list_head);

	desc.args[1] = info_list->list_size;

	desc.args[0] = virt_to_phys(sg_table_copy);

	desc.args[1] = sg_table_copy_size;

	desc.args[2] = virt_to_phys(source_vm_copy);

	desc.args[3] = sizeof(*source_vm_copy) * source_nelems;

	desc.args[4] = virt_to_phys(dest_info_list->dest_info);

	desc.args[5] = dest_info_list->list_size;

	desc.args[3] = source_vm_copy_size;

	desc.args[4] = virt_to_phys(dest_vm_copy);

	desc.args[5] = dest_vm_copy_size;

	desc.args[6] = 0;



	desc.arginfo = SCM_ARGS(7, SCM_RO, SCM_VAL, SCM_RO, SCM_VAL, SCM_RO,

				SCM_VAL, SCM_VAL);



	dmac_flush_range(source_vm_copy, source_vm_copy + source_nelems);

	dmac_flush_range(info_list->list_head, info_list->list_head +

		(info_list->list_size / sizeof(*info_list->list_head)));

	dmac_flush_range(dest_info_list->dest_info, dest_info_list->dest_info +

		(dest_info_list->list_size /

				sizeof(*dest_info_list->dest_info)));

	dmac_flush_range(source_vm_copy,

			 (void *)source_vm_copy + source_vm_copy_size);

	dmac_flush_range(sg_table_copy,

			 (void *)sg_table_copy + sg_table_copy_size);

	dmac_flush_range(dest_vm_copy,

			 (void *)dest_vm_copy + dest_vm_copy_size);



	ret = scm_call2(SCM_SIP_FNID(SCM_SVC_MP,

			MEM_PROT_ASSIGN_ID), &desc);
@@ -316,7 +318,10 @@ int hyp_assign_table(struct sg_table *table, 
		pr_info("%s: Failed to assign memory protection, ret = %d\n",

			__func__, ret);



out_unlock:

	mutex_unlock(&secure_buffer_mutex);

	kfree(dest_vm_copy);

out_free:

	kfree(source_vm_copy);

	return ret;

}