tee: optee: add page list manipulation functions (3bb48ba5) · Commits · 戴 / test

drivers/tee/optee/call.c

+91 −0

Original line number	Diff line number	Diff line
		@@ -11,6 +11,7 @@
		* GNU General Public License for more details.
		*
		*/
		#include <asm/pgtable.h>
		#include <linux/arm-smccc.h>
		#include <linux/device.h>
		#include <linux/err.h>
		@@ -442,3 +443,93 @@ void optee_disable_shm_cache(struct optee *optee)
		}
		optee_cq_wait_final(&optee->call_queue, &w);
		}

		#define PAGELIST_ENTRIES_PER_PAGE \
		((OPTEE_MSG_NONCONTIG_PAGE_SIZE / sizeof(u64)) - 1)

		/**
		* optee_fill_pages_list() - write list of user pages to given shared
		* buffer.
		*
		* @dst: page-aligned buffer where list of pages will be stored
		* @pages: array of pages that represents shared buffer
		* @num_pages: number of entries in @pages
		* @page_offset: offset of user buffer from page start
		*
		* @dst should be big enough to hold list of user page addresses and
		* links to the next pages of buffer
		*/
		void optee_fill_pages_list(u64 dst, struct page *pages, int num_pages,
		size_t page_offset)
		{
		int n = 0;
		phys_addr_t optee_page;
		/*
		* Refer to OPTEE_MSG_ATTR_NONCONTIG description in optee_msg.h
		* for details.
		*/
		struct {
		u64 pages_list[PAGELIST_ENTRIES_PER_PAGE];
		u64 next_page_data;
		} *pages_data;

		/*
		* Currently OP-TEE uses 4k page size and it does not looks
		* like this will change in the future. On other hand, there are
		* no know ARM architectures with page size < 4k.
		* Thus the next built assert looks redundant. But the following
		* code heavily relies on this assumption, so it is better be
		* safe than sorry.
		*/
		BUILD_BUG_ON(PAGE_SIZE < OPTEE_MSG_NONCONTIG_PAGE_SIZE);

		pages_data = (void *)dst;
		/*
		* If linux page is bigger than 4k, and user buffer offset is
		* larger than 4k/8k/12k/etc this will skip first 4k pages,
		* because they bear no value data for OP-TEE.
		*/
		optee_page = page_to_phys(*pages) +
		round_down(page_offset, OPTEE_MSG_NONCONTIG_PAGE_SIZE);

		while (true) {
		pages_data->pages_list[n++] = optee_page;

		if (n == PAGELIST_ENTRIES_PER_PAGE) {
		pages_data->next_page_data =
		virt_to_phys(pages_data + 1);
		pages_data++;
		n = 0;
		}

		optee_page += OPTEE_MSG_NONCONTIG_PAGE_SIZE;
		if (!(optee_page & ~PAGE_MASK)) {
		if (!--num_pages)
		break;
		pages++;
		optee_page = page_to_phys(*pages);
		}
		}
		}

		/*
		* The final entry in each pagelist page is a pointer to the next
		* pagelist page.
		*/
		static size_t get_pages_list_size(size_t num_entries)
		{
		int pages = DIV_ROUND_UP(num_entries, PAGELIST_ENTRIES_PER_PAGE);

		return pages * OPTEE_MSG_NONCONTIG_PAGE_SIZE;
		}

		u64 *optee_allocate_pages_list(size_t num_entries)
		{
		return alloc_pages_exact(get_pages_list_size(num_entries), GFP_KERNEL);
		}

		void optee_free_pages_list(void *list, size_t num_entries)
		{
		free_pages_exact(list, get_pages_list_size(num_entries));
		}

drivers/tee/optee/optee_private.h

+5 −0

Original line number	Diff line number	Diff line
		@@ -165,6 +165,11 @@ int optee_from_msg_param(struct tee_param *params, size_t num_params,
		int optee_to_msg_param(struct optee_msg_param *msg_params, size_t num_params,
		const struct tee_param *params);

		u64 *optee_allocate_pages_list(size_t num_entries);
		void optee_free_pages_list(void *array, size_t num_entries);
		void optee_fill_pages_list(u64 dst, struct page *pages, int num_pages,
		size_t page_offset);

		/*
		* Small helpers
		*/

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