[PATCH v2 03/12] tee: add tee_shm_alloc_user_buf()

From: Jens Wiklander
Date: Fri Jan 14 2022 - 10:08:55 EST


Adds a new function tee_shm_alloc_user_buf() or user mode allocations,
replacing passing the flags TEE_SHM_MAPPED | TEE_SHM_DMA_BUF to
tee_shm_alloc().

Signed-off-by: Jens Wiklander <jens.wiklander@xxxxxxxxxx>
---
drivers/tee/tee_core.c | 2 +-
drivers/tee/tee_shm.c | 18 ++++++++++++++++++
drivers/tee/tee_shm_pool.c | 2 +-
include/linux/tee_drv.h | 3 ++-
4 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index 3fc426dad2df..a15812baaeb1 100644
--- a/drivers/tee/tee_core.c
+++ b/drivers/tee/tee_core.c
@@ -297,7 +297,7 @@ static int tee_ioctl_shm_alloc(struct tee_context *ctx,
if (data.flags)
return -EINVAL;

- shm = tee_shm_alloc(ctx, data.size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
+ shm = tee_shm_alloc_user_buf(ctx, data.size);
if (IS_ERR(shm))
return PTR_ERR(shm);

diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
index 499fccba3d74..b43178986985 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -127,6 +127,24 @@ struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags)
}
EXPORT_SYMBOL_GPL(tee_shm_alloc);

+/**
+ * tee_shm_alloc_user_buf() - Allocate shared memory for user space
+ * @ctx: Context that allocates the shared memory
+ * @size: Requested size of shared memory
+ *
+ * Memory allocated as user space shared memory is automatically freed when
+ * the TEE file pointer is closed. The primary usage of this function is
+ * when the TEE driver doesn't support registering ordinary user space
+ * memory.
+ *
+ * @returns a pointer to 'struct tee_shm'
+ */
+struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size)
+{
+ return tee_shm_alloc(ctx, size, TEE_SHM_MAPPED | TEE_SHM_DMA_BUF);
+}
+EXPORT_SYMBOL_GPL(tee_shm_alloc_user_buf);
+
/**
* tee_shm_alloc_kernel_buf() - Allocate shared memory for kernel buffer
* @ctx: Context that allocates the shared memory
diff --git a/drivers/tee/tee_shm_pool.c b/drivers/tee/tee_shm_pool.c
index a9f9d50fd181..0e460347138a 100644
--- a/drivers/tee/tee_shm_pool.c
+++ b/drivers/tee/tee_shm_pool.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * Copyright (c) 2015, Linaro Limited
+ * Copyright (c) 2015, 2017, 2022 Linaro Limited
*/
#include <linux/device.h>
#include <linux/dma-buf.h>
diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index 6b0f0d01ebdf..26b450484ac1 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
- * Copyright (c) 2015-2016, Linaro Limited
+ * Copyright (c) 2015-2022 Linaro Limited
*/

#ifndef __TEE_DRV_H
@@ -308,6 +308,7 @@ void *tee_get_drvdata(struct tee_device *teedev);
* @returns a pointer to 'struct tee_shm'
*/
struct tee_shm *tee_shm_alloc(struct tee_context *ctx, size_t size, u32 flags);
+struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size);
struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size);

/**
--
2.31.1