Add tee_shm_alloc_dma_mem() to allocate DMA memory. The memory is
represented by a tee_shm object using the new flag TEE_SHM_DMA_MEM to
identify it as DMA memory. The allocated memory will later be lent to
the TEE to be used as protected memory.
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
---
drivers/tee/tee_shm.c | 85 +++++++++++++++++++++++++++++++++++++++-
include/linux/tee_core.h | 5 +++
2 files changed, 88 insertions(+), 2 deletions(-)
diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
index e63095e84644..60b0f3932cee 100644
--- a/drivers/tee/tee_shm.c
+++ b/drivers/tee/tee_shm.c
@@ -5,6 +5,8 @@
#include <linux/anon_inodes.h>
#include <linux/device.h>
#include <linux/dma-buf.h>
+#include <linux/dma-mapping.h>
+#include <linux/highmem.h>
#include <linux/idr.h>
#include <linux/io.h>
#include <linux/mm.h>
@@ -13,9 +15,14 @@
#include <linux/tee_core.h>
#include <linux/uaccess.h>
#include <linux/uio.h>
-#include <linux/highmem.h>
#include "tee_private.h"
+struct tee_shm_dma_mem {
+ struct tee_shm shm;
+ dma_addr_t dma_addr;
+ struct page *page;
+};
+
static void shm_put_kernel_pages(struct page **pages, size_t page_count)
{
size_t n;
@@ -48,7 +55,16 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm)
{
void *p = shm;
- if (shm->flags & TEE_SHM_DMA_BUF) {
+ if (shm->flags & TEE_SHM_DMA_MEM) {
+#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
+ struct tee_shm_dma_mem *dma_mem;
+
+ dma_mem = container_of(shm, struct tee_shm_dma_mem, shm);
+ p = dma_mem;
+ dma_free_pages(&teedev->dev, shm->size, dma_mem->page,
+ dma_mem->dma_addr, DMA_BIDIRECTIONAL);
+#endif
+ } else if (shm->flags & TEE_SHM_DMA_BUF) {
struct tee_shm_dmabuf_ref *ref;
ref = container_of(shm, struct tee_shm_dmabuf_ref, shm);
@@ -303,6 +319,71 @@ struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size)
}
EXPORT_SYMBOL_GPL(tee_shm_alloc_priv_buf);
+#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
+/**
+ * tee_shm_alloc_dma_mem() - Allocate DMA memory as shared memory object
+ * @ctx: Context that allocates the shared memory
+ * @page_count: Number of pages
+ *
+ * The allocated memory is expected to be lent (made inaccessible to the
+ * kernel) to the TEE while it's used and returned (accessible to the
+ * kernel again) before it's freed.
+ *
+ * This function should normally only be used internally in the TEE
+ * drivers.
+ *
+ * @returns a pointer to 'struct tee_shm'
+ */
+struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
+ size_t page_count)
+{
+ struct tee_device *teedev = ctx->teedev;
+ struct tee_shm_dma_mem *dma_mem;
+ dma_addr_t dma_addr;
+ struct page *page;
+
+ if (!tee_device_get(teedev))
+ return ERR_PTR(-EINVAL);
+
+ page = dma_alloc_pages(&teedev->dev, page_count * PAGE_SIZE,
+ &dma_addr, DMA_BIDIRECTIONAL, GFP_KERNEL);
+ if (!page)
+ goto err_put_teedev;
+
+ dma_mem = kzalloc(sizeof(*dma_mem), GFP_KERNEL);
+ if (!dma_mem)
+ goto err_free_pages;
+
+ refcount_set(&dma_mem->shm.refcount, 1);
+ dma_mem->shm.ctx = ctx;
+ dma_mem->shm.paddr = page_to_phys(page);
+ dma_mem->dma_addr = dma_addr;
+ dma_mem->page = page;
+ dma_mem->shm.size = page_count * PAGE_SIZE;
+ dma_mem->shm.flags = TEE_SHM_DMA_MEM;
+
+ teedev_ctx_get(ctx);
+
+ return &dma_mem->shm;
+
+err_free_pages:
+ dma_free_pages(&teedev->dev, page_count * PAGE_SIZE, page, dma_addr,
+ DMA_BIDIRECTIONAL);
+err_put_teedev:
+ tee_device_put(teedev);
+
+ return ERR_PTR(-ENOMEM);
+}
+EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
+#else
+struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
+ size_t page_count)
+{
+ return ERR_PTR(-EINVAL);
+}
+EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
+#endif
+
int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
int (*shm_register)(struct tee_context *ctx,
struct tee_shm *shm,
diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h
index f17710196c4c..e46a53e753af 100644
--- a/include/linux/tee_core.h
+++ b/include/linux/tee_core.h
@@ -29,6 +29,8 @@
#define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */
#define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */
#define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */
+#define TEE_SHM_DMA_MEM BIT(5) /* Memory allocated with */
+ /* dma_alloc_pages() */
#define TEE_DEVICE_FLAG_REGISTERED 0x1
#define TEE_MAX_DEV_NAME_LEN 32
@@ -310,6 +312,9 @@ void *tee_get_drvdata(struct tee_device *teedev);
*/
struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size);
+struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
+ size_t page_count);
+
int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
int (*shm_register)(struct tee_context *ctx,
struct tee_shm *shm,
--
2.43.0On Tue, Jun 10, 2025 at 03:13:50PM +0200, Jens Wiklander wrote:
> Add tee_shm_alloc_dma_mem() to allocate DMA memory. The memory is
> represented by a tee_shm object using the new flag TEE_SHM_DMA_MEM to
> identify it as DMA memory. The allocated memory will later be lent to
> the TEE to be used as protected memory.
>
> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> ---
> drivers/tee/tee_shm.c | 85 +++++++++++++++++++++++++++++++++++++++-
> include/linux/tee_core.h | 5 +++
> 2 files changed, 88 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
> index e63095e84644..60b0f3932cee 100644
> --- a/drivers/tee/tee_shm.c
> +++ b/drivers/tee/tee_shm.c
> @@ -5,6 +5,8 @@
> #include <linux/anon_inodes.h>
> #include <linux/device.h>
> #include <linux/dma-buf.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/highmem.h>
> #include <linux/idr.h>
> #include <linux/io.h>
> #include <linux/mm.h>
> @@ -13,9 +15,14 @@
> #include <linux/tee_core.h>
> #include <linux/uaccess.h>
> #include <linux/uio.h>
> -#include <linux/highmem.h>
> #include "tee_private.h"
>
> +struct tee_shm_dma_mem {
> + struct tee_shm shm;
> + dma_addr_t dma_addr;
> + struct page *page;
> +};
> +
> static void shm_put_kernel_pages(struct page **pages, size_t page_count)
> {
> size_t n;
> @@ -48,7 +55,16 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm)
> {
> void *p = shm;
>
> - if (shm->flags & TEE_SHM_DMA_BUF) {
> + if (shm->flags & TEE_SHM_DMA_MEM) {
> +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
nit: this config check can be merged into the above if check.
> + struct tee_shm_dma_mem *dma_mem;
> +
> + dma_mem = container_of(shm, struct tee_shm_dma_mem, shm);
> + p = dma_mem;
> + dma_free_pages(&teedev->dev, shm->size, dma_mem->page,
> + dma_mem->dma_addr, DMA_BIDIRECTIONAL);
> +#endif
> + } else if (shm->flags & TEE_SHM_DMA_BUF) {
Do we need a similar config check for this flag too?
With these addressed, feel free to add:
Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
-Sumit
> struct tee_shm_dmabuf_ref *ref;
>
> ref = container_of(shm, struct tee_shm_dmabuf_ref, shm);
> @@ -303,6 +319,71 @@ struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size)
> }
> EXPORT_SYMBOL_GPL(tee_shm_alloc_priv_buf);
>
> +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
> +/**
> + * tee_shm_alloc_dma_mem() - Allocate DMA memory as shared memory object
> + * @ctx: Context that allocates the shared memory
> + * @page_count: Number of pages
> + *
> + * The allocated memory is expected to be lent (made inaccessible to the
> + * kernel) to the TEE while it's used and returned (accessible to the
> + * kernel again) before it's freed.
> + *
> + * This function should normally only be used internally in the TEE
> + * drivers.
> + *
> + * @returns a pointer to 'struct tee_shm'
> + */
> +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> + size_t page_count)
> +{
> + struct tee_device *teedev = ctx->teedev;
> + struct tee_shm_dma_mem *dma_mem;
> + dma_addr_t dma_addr;
> + struct page *page;
> +
> + if (!tee_device_get(teedev))
> + return ERR_PTR(-EINVAL);
> +
> + page = dma_alloc_pages(&teedev->dev, page_count * PAGE_SIZE,
> + &dma_addr, DMA_BIDIRECTIONAL, GFP_KERNEL);
> + if (!page)
> + goto err_put_teedev;
> +
> + dma_mem = kzalloc(sizeof(*dma_mem), GFP_KERNEL);
> + if (!dma_mem)
> + goto err_free_pages;
> +
> + refcount_set(&dma_mem->shm.refcount, 1);
> + dma_mem->shm.ctx = ctx;
> + dma_mem->shm.paddr = page_to_phys(page);
> + dma_mem->dma_addr = dma_addr;
> + dma_mem->page = page;
> + dma_mem->shm.size = page_count * PAGE_SIZE;
> + dma_mem->shm.flags = TEE_SHM_DMA_MEM;
> +
> + teedev_ctx_get(ctx);
> +
> + return &dma_mem->shm;
> +
> +err_free_pages:
> + dma_free_pages(&teedev->dev, page_count * PAGE_SIZE, page, dma_addr,
> + DMA_BIDIRECTIONAL);
> +err_put_teedev:
> + tee_device_put(teedev);
> +
> + return ERR_PTR(-ENOMEM);
> +}
> +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> +#else
> +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> + size_t page_count)
> +{
> + return ERR_PTR(-EINVAL);
> +}
> +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> +#endif
> +
> int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> int (*shm_register)(struct tee_context *ctx,
> struct tee_shm *shm,
> diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h
> index f17710196c4c..e46a53e753af 100644
> --- a/include/linux/tee_core.h
> +++ b/include/linux/tee_core.h
> @@ -29,6 +29,8 @@
> #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */
> #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */
> #define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */
> +#define TEE_SHM_DMA_MEM BIT(5) /* Memory allocated with */
> + /* dma_alloc_pages() */
>
> #define TEE_DEVICE_FLAG_REGISTERED 0x1
> #define TEE_MAX_DEV_NAME_LEN 32
> @@ -310,6 +312,9 @@ void *tee_get_drvdata(struct tee_device *teedev);
> */
> struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size);
>
> +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> + size_t page_count);
> +
> int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> int (*shm_register)(struct tee_context *ctx,
> struct tee_shm *shm,
> --
> 2.43.0
>
On Tue, Jun 17, 2025 at 1:32 PM Sumit Garg <sumit.garg@kernel.org> wrote:
>
> On Tue, Jun 10, 2025 at 03:13:50PM +0200, Jens Wiklander wrote:
> > Add tee_shm_alloc_dma_mem() to allocate DMA memory. The memory is
> > represented by a tee_shm object using the new flag TEE_SHM_DMA_MEM to
> > identify it as DMA memory. The allocated memory will later be lent to
> > the TEE to be used as protected memory.
> >
> > Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> > ---
> > drivers/tee/tee_shm.c | 85 +++++++++++++++++++++++++++++++++++++++-
> > include/linux/tee_core.h | 5 +++
> > 2 files changed, 88 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
> > index e63095e84644..60b0f3932cee 100644
> > --- a/drivers/tee/tee_shm.c
> > +++ b/drivers/tee/tee_shm.c
> > @@ -5,6 +5,8 @@
> > #include <linux/anon_inodes.h>
> > #include <linux/device.h>
> > #include <linux/dma-buf.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/highmem.h>
> > #include <linux/idr.h>
> > #include <linux/io.h>
> > #include <linux/mm.h>
> > @@ -13,9 +15,14 @@
> > #include <linux/tee_core.h>
> > #include <linux/uaccess.h>
> > #include <linux/uio.h>
> > -#include <linux/highmem.h>
> > #include "tee_private.h"
> >
> > +struct tee_shm_dma_mem {
> > + struct tee_shm shm;
> > + dma_addr_t dma_addr;
> > + struct page *page;
> > +};
> > +
> > static void shm_put_kernel_pages(struct page **pages, size_t page_count)
> > {
> > size_t n;
> > @@ -48,7 +55,16 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm)
> > {
> > void *p = shm;
> >
> > - if (shm->flags & TEE_SHM_DMA_BUF) {
> > + if (shm->flags & TEE_SHM_DMA_MEM) {
> > +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
>
> nit: this config check can be merged into the above if check.
No, because dma_free_pages() is only defined if
CONFIG_TEE_DMABUF_HEAPS is enabled.
>
> > + struct tee_shm_dma_mem *dma_mem;
> > +
> > + dma_mem = container_of(shm, struct tee_shm_dma_mem, shm);
> > + p = dma_mem;
> > + dma_free_pages(&teedev->dev, shm->size, dma_mem->page,
> > + dma_mem->dma_addr, DMA_BIDIRECTIONAL);
> > +#endif
> > + } else if (shm->flags & TEE_SHM_DMA_BUF) {
>
> Do we need a similar config check for this flag too?
No, because DMA_SHARED_BUFFER is selected, so the dma_buf functions are defined.
Cheers,
Jens
>
> With these addressed, feel free to add:
>
> Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
>
> -Sumit
>
> > struct tee_shm_dmabuf_ref *ref;
> >
> > ref = container_of(shm, struct tee_shm_dmabuf_ref, shm);
> > @@ -303,6 +319,71 @@ struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size)
> > }
> > EXPORT_SYMBOL_GPL(tee_shm_alloc_priv_buf);
> >
> > +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
> > +/**
> > + * tee_shm_alloc_dma_mem() - Allocate DMA memory as shared memory object
> > + * @ctx: Context that allocates the shared memory
> > + * @page_count: Number of pages
> > + *
> > + * The allocated memory is expected to be lent (made inaccessible to the
> > + * kernel) to the TEE while it's used and returned (accessible to the
> > + * kernel again) before it's freed.
> > + *
> > + * This function should normally only be used internally in the TEE
> > + * drivers.
> > + *
> > + * @returns a pointer to 'struct tee_shm'
> > + */
> > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > + size_t page_count)
> > +{
> > + struct tee_device *teedev = ctx->teedev;
> > + struct tee_shm_dma_mem *dma_mem;
> > + dma_addr_t dma_addr;
> > + struct page *page;
> > +
> > + if (!tee_device_get(teedev))
> > + return ERR_PTR(-EINVAL);
> > +
> > + page = dma_alloc_pages(&teedev->dev, page_count * PAGE_SIZE,
> > + &dma_addr, DMA_BIDIRECTIONAL, GFP_KERNEL);
> > + if (!page)
> > + goto err_put_teedev;
> > +
> > + dma_mem = kzalloc(sizeof(*dma_mem), GFP_KERNEL);
> > + if (!dma_mem)
> > + goto err_free_pages;
> > +
> > + refcount_set(&dma_mem->shm.refcount, 1);
> > + dma_mem->shm.ctx = ctx;
> > + dma_mem->shm.paddr = page_to_phys(page);
> > + dma_mem->dma_addr = dma_addr;
> > + dma_mem->page = page;
> > + dma_mem->shm.size = page_count * PAGE_SIZE;
> > + dma_mem->shm.flags = TEE_SHM_DMA_MEM;
> > +
> > + teedev_ctx_get(ctx);
> > +
> > + return &dma_mem->shm;
> > +
> > +err_free_pages:
> > + dma_free_pages(&teedev->dev, page_count * PAGE_SIZE, page, dma_addr,
> > + DMA_BIDIRECTIONAL);
> > +err_put_teedev:
> > + tee_device_put(teedev);
> > +
> > + return ERR_PTR(-ENOMEM);
> > +}
> > +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> > +#else
> > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > + size_t page_count)
> > +{
> > + return ERR_PTR(-EINVAL);
> > +}
> > +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> > +#endif
> > +
> > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> > int (*shm_register)(struct tee_context *ctx,
> > struct tee_shm *shm,
> > diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h
> > index f17710196c4c..e46a53e753af 100644
> > --- a/include/linux/tee_core.h
> > +++ b/include/linux/tee_core.h
> > @@ -29,6 +29,8 @@
> > #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */
> > #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */
> > #define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */
> > +#define TEE_SHM_DMA_MEM BIT(5) /* Memory allocated with */
> > + /* dma_alloc_pages() */
> >
> > #define TEE_DEVICE_FLAG_REGISTERED 0x1
> > #define TEE_MAX_DEV_NAME_LEN 32
> > @@ -310,6 +312,9 @@ void *tee_get_drvdata(struct tee_device *teedev);
> > */
> > struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size);
> >
> > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > + size_t page_count);
> > +
> > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> > int (*shm_register)(struct tee_context *ctx,
> > struct tee_shm *shm,
> > --
> > 2.43.0
> >
On Wed, Jun 18, 2025 at 09:03:00AM +0200, Jens Wiklander wrote:
> On Tue, Jun 17, 2025 at 1:32 PM Sumit Garg <sumit.garg@kernel.org> wrote:
> >
> > On Tue, Jun 10, 2025 at 03:13:50PM +0200, Jens Wiklander wrote:
> > > Add tee_shm_alloc_dma_mem() to allocate DMA memory. The memory is
> > > represented by a tee_shm object using the new flag TEE_SHM_DMA_MEM to
> > > identify it as DMA memory. The allocated memory will later be lent to
> > > the TEE to be used as protected memory.
> > >
> > > Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> > > ---
> > > drivers/tee/tee_shm.c | 85 +++++++++++++++++++++++++++++++++++++++-
> > > include/linux/tee_core.h | 5 +++
> > > 2 files changed, 88 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
> > > index e63095e84644..60b0f3932cee 100644
> > > --- a/drivers/tee/tee_shm.c
> > > +++ b/drivers/tee/tee_shm.c
> > > @@ -5,6 +5,8 @@
> > > #include <linux/anon_inodes.h>
> > > #include <linux/device.h>
> > > #include <linux/dma-buf.h>
> > > +#include <linux/dma-mapping.h>
> > > +#include <linux/highmem.h>
> > > #include <linux/idr.h>
> > > #include <linux/io.h>
> > > #include <linux/mm.h>
> > > @@ -13,9 +15,14 @@
> > > #include <linux/tee_core.h>
> > > #include <linux/uaccess.h>
> > > #include <linux/uio.h>
> > > -#include <linux/highmem.h>
> > > #include "tee_private.h"
> > >
> > > +struct tee_shm_dma_mem {
> > > + struct tee_shm shm;
> > > + dma_addr_t dma_addr;
> > > + struct page *page;
> > > +};
> > > +
> > > static void shm_put_kernel_pages(struct page **pages, size_t page_count)
> > > {
> > > size_t n;
> > > @@ -48,7 +55,16 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm)
> > > {
> > > void *p = shm;
> > >
> > > - if (shm->flags & TEE_SHM_DMA_BUF) {
> > > + if (shm->flags & TEE_SHM_DMA_MEM) {
> > > +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
> >
> > nit: this config check can be merged into the above if check.
>
> No, because dma_free_pages() is only defined if
> CONFIG_TEE_DMABUF_HEAPS is enabled.
It looks like you misunderstood my above comment, I rather meant:
if (IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS) &&
(shm->flags & TEE_SHM_DMA_MEM))
-Sumit
>
> >
> > > + struct tee_shm_dma_mem *dma_mem;
> > > +
> > > + dma_mem = container_of(shm, struct tee_shm_dma_mem, shm);
> > > + p = dma_mem;
> > > + dma_free_pages(&teedev->dev, shm->size, dma_mem->page,
> > > + dma_mem->dma_addr, DMA_BIDIRECTIONAL);
> > > +#endif
> > > + } else if (shm->flags & TEE_SHM_DMA_BUF) {
> >
> > Do we need a similar config check for this flag too?
>
> No, because DMA_SHARED_BUFFER is selected, so the dma_buf functions are defined.
>
> Cheers,
> Jens
>
>
> >
> > With these addressed, feel free to add:
> >
> > Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
> >
> > -Sumit
> >
> > > struct tee_shm_dmabuf_ref *ref;
> > >
> > > ref = container_of(shm, struct tee_shm_dmabuf_ref, shm);
> > > @@ -303,6 +319,71 @@ struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size)
> > > }
> > > EXPORT_SYMBOL_GPL(tee_shm_alloc_priv_buf);
> > >
> > > +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
> > > +/**
> > > + * tee_shm_alloc_dma_mem() - Allocate DMA memory as shared memory object
> > > + * @ctx: Context that allocates the shared memory
> > > + * @page_count: Number of pages
> > > + *
> > > + * The allocated memory is expected to be lent (made inaccessible to the
> > > + * kernel) to the TEE while it's used and returned (accessible to the
> > > + * kernel again) before it's freed.
> > > + *
> > > + * This function should normally only be used internally in the TEE
> > > + * drivers.
> > > + *
> > > + * @returns a pointer to 'struct tee_shm'
> > > + */
> > > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > > + size_t page_count)
> > > +{
> > > + struct tee_device *teedev = ctx->teedev;
> > > + struct tee_shm_dma_mem *dma_mem;
> > > + dma_addr_t dma_addr;
> > > + struct page *page;
> > > +
> > > + if (!tee_device_get(teedev))
> > > + return ERR_PTR(-EINVAL);
> > > +
> > > + page = dma_alloc_pages(&teedev->dev, page_count * PAGE_SIZE,
> > > + &dma_addr, DMA_BIDIRECTIONAL, GFP_KERNEL);
> > > + if (!page)
> > > + goto err_put_teedev;
> > > +
> > > + dma_mem = kzalloc(sizeof(*dma_mem), GFP_KERNEL);
> > > + if (!dma_mem)
> > > + goto err_free_pages;
> > > +
> > > + refcount_set(&dma_mem->shm.refcount, 1);
> > > + dma_mem->shm.ctx = ctx;
> > > + dma_mem->shm.paddr = page_to_phys(page);
> > > + dma_mem->dma_addr = dma_addr;
> > > + dma_mem->page = page;
> > > + dma_mem->shm.size = page_count * PAGE_SIZE;
> > > + dma_mem->shm.flags = TEE_SHM_DMA_MEM;
> > > +
> > > + teedev_ctx_get(ctx);
> > > +
> > > + return &dma_mem->shm;
> > > +
> > > +err_free_pages:
> > > + dma_free_pages(&teedev->dev, page_count * PAGE_SIZE, page, dma_addr,
> > > + DMA_BIDIRECTIONAL);
> > > +err_put_teedev:
> > > + tee_device_put(teedev);
> > > +
> > > + return ERR_PTR(-ENOMEM);
> > > +}
> > > +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> > > +#else
> > > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > > + size_t page_count)
> > > +{
> > > + return ERR_PTR(-EINVAL);
> > > +}
> > > +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> > > +#endif
> > > +
> > > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> > > int (*shm_register)(struct tee_context *ctx,
> > > struct tee_shm *shm,
> > > diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h
> > > index f17710196c4c..e46a53e753af 100644
> > > --- a/include/linux/tee_core.h
> > > +++ b/include/linux/tee_core.h
> > > @@ -29,6 +29,8 @@
> > > #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */
> > > #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */
> > > #define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */
> > > +#define TEE_SHM_DMA_MEM BIT(5) /* Memory allocated with */
> > > + /* dma_alloc_pages() */
> > >
> > > #define TEE_DEVICE_FLAG_REGISTERED 0x1
> > > #define TEE_MAX_DEV_NAME_LEN 32
> > > @@ -310,6 +312,9 @@ void *tee_get_drvdata(struct tee_device *teedev);
> > > */
> > > struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size);
> > >
> > > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > > + size_t page_count);
> > > +
> > > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> > > int (*shm_register)(struct tee_context *ctx,
> > > struct tee_shm *shm,
> > > --
> > > 2.43.0
> > >
On Thu, Jul 3, 2025 at 8:28 AM Sumit Garg <sumit.garg@kernel.org> wrote:
>
> On Wed, Jun 18, 2025 at 09:03:00AM +0200, Jens Wiklander wrote:
> > On Tue, Jun 17, 2025 at 1:32 PM Sumit Garg <sumit.garg@kernel.org> wrote:
> > >
> > > On Tue, Jun 10, 2025 at 03:13:50PM +0200, Jens Wiklander wrote:
> > > > Add tee_shm_alloc_dma_mem() to allocate DMA memory. The memory is
> > > > represented by a tee_shm object using the new flag TEE_SHM_DMA_MEM to
> > > > identify it as DMA memory. The allocated memory will later be lent to
> > > > the TEE to be used as protected memory.
> > > >
> > > > Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> > > > ---
> > > > drivers/tee/tee_shm.c | 85 +++++++++++++++++++++++++++++++++++++++-
> > > > include/linux/tee_core.h | 5 +++
> > > > 2 files changed, 88 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
> > > > index e63095e84644..60b0f3932cee 100644
> > > > --- a/drivers/tee/tee_shm.c
> > > > +++ b/drivers/tee/tee_shm.c
> > > > @@ -5,6 +5,8 @@
> > > > #include <linux/anon_inodes.h>
> > > > #include <linux/device.h>
> > > > #include <linux/dma-buf.h>
> > > > +#include <linux/dma-mapping.h>
> > > > +#include <linux/highmem.h>
> > > > #include <linux/idr.h>
> > > > #include <linux/io.h>
> > > > #include <linux/mm.h>
> > > > @@ -13,9 +15,14 @@
> > > > #include <linux/tee_core.h>
> > > > #include <linux/uaccess.h>
> > > > #include <linux/uio.h>
> > > > -#include <linux/highmem.h>
> > > > #include "tee_private.h"
> > > >
> > > > +struct tee_shm_dma_mem {
> > > > + struct tee_shm shm;
> > > > + dma_addr_t dma_addr;
> > > > + struct page *page;
> > > > +};
> > > > +
> > > > static void shm_put_kernel_pages(struct page **pages, size_t page_count)
> > > > {
> > > > size_t n;
> > > > @@ -48,7 +55,16 @@ static void tee_shm_release(struct tee_device *teedev, struct tee_shm *shm)
> > > > {
> > > > void *p = shm;
> > > >
> > > > - if (shm->flags & TEE_SHM_DMA_BUF) {
> > > > + if (shm->flags & TEE_SHM_DMA_MEM) {
> > > > +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
> > >
> > > nit: this config check can be merged into the above if check.
> >
> > No, because dma_free_pages() is only defined if
> > CONFIG_TEE_DMABUF_HEAPS is enabled.
>
> It looks like you misunderstood my above comment, I rather meant:
>
> if (IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS) &&
> (shm->flags & TEE_SHM_DMA_MEM))
That depends on the compiler optimizing away the call to
dma_free_pages() if CONFIG_TEE_DMABUF_HEAPS isn't defined. This is
normally the case, but if you compile for debugging, you may get
unresolved symbols.
Cheers,
Jens
>
> -Sumit
>
> >
> > >
> > > > + struct tee_shm_dma_mem *dma_mem;
> > > > +
> > > > + dma_mem = container_of(shm, struct tee_shm_dma_mem, shm);
> > > > + p = dma_mem;
> > > > + dma_free_pages(&teedev->dev, shm->size, dma_mem->page,
> > > > + dma_mem->dma_addr, DMA_BIDIRECTIONAL);
> > > > +#endif
> > > > + } else if (shm->flags & TEE_SHM_DMA_BUF) {
> > >
> > > Do we need a similar config check for this flag too?
> >
> > No, because DMA_SHARED_BUFFER is selected, so the dma_buf functions are defined.
> >
> > Cheers,
> > Jens
> >
> >
> > >
> > > With these addressed, feel free to add:
> > >
> > > Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
> > >
> > > -Sumit
> > >
> > > > struct tee_shm_dmabuf_ref *ref;
> > > >
> > > > ref = container_of(shm, struct tee_shm_dmabuf_ref, shm);
> > > > @@ -303,6 +319,71 @@ struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size)
> > > > }
> > > > EXPORT_SYMBOL_GPL(tee_shm_alloc_priv_buf);
> > > >
> > > > +#if IS_ENABLED(CONFIG_TEE_DMABUF_HEAPS)
> > > > +/**
> > > > + * tee_shm_alloc_dma_mem() - Allocate DMA memory as shared memory object
> > > > + * @ctx: Context that allocates the shared memory
> > > > + * @page_count: Number of pages
> > > > + *
> > > > + * The allocated memory is expected to be lent (made inaccessible to the
> > > > + * kernel) to the TEE while it's used and returned (accessible to the
> > > > + * kernel again) before it's freed.
> > > > + *
> > > > + * This function should normally only be used internally in the TEE
> > > > + * drivers.
> > > > + *
> > > > + * @returns a pointer to 'struct tee_shm'
> > > > + */
> > > > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > > > + size_t page_count)
> > > > +{
> > > > + struct tee_device *teedev = ctx->teedev;
> > > > + struct tee_shm_dma_mem *dma_mem;
> > > > + dma_addr_t dma_addr;
> > > > + struct page *page;
> > > > +
> > > > + if (!tee_device_get(teedev))
> > > > + return ERR_PTR(-EINVAL);
> > > > +
> > > > + page = dma_alloc_pages(&teedev->dev, page_count * PAGE_SIZE,
> > > > + &dma_addr, DMA_BIDIRECTIONAL, GFP_KERNEL);
> > > > + if (!page)
> > > > + goto err_put_teedev;
> > > > +
> > > > + dma_mem = kzalloc(sizeof(*dma_mem), GFP_KERNEL);
> > > > + if (!dma_mem)
> > > > + goto err_free_pages;
> > > > +
> > > > + refcount_set(&dma_mem->shm.refcount, 1);
> > > > + dma_mem->shm.ctx = ctx;
> > > > + dma_mem->shm.paddr = page_to_phys(page);
> > > > + dma_mem->dma_addr = dma_addr;
> > > > + dma_mem->page = page;
> > > > + dma_mem->shm.size = page_count * PAGE_SIZE;
> > > > + dma_mem->shm.flags = TEE_SHM_DMA_MEM;
> > > > +
> > > > + teedev_ctx_get(ctx);
> > > > +
> > > > + return &dma_mem->shm;
> > > > +
> > > > +err_free_pages:
> > > > + dma_free_pages(&teedev->dev, page_count * PAGE_SIZE, page, dma_addr,
> > > > + DMA_BIDIRECTIONAL);
> > > > +err_put_teedev:
> > > > + tee_device_put(teedev);
> > > > +
> > > > + return ERR_PTR(-ENOMEM);
> > > > +}
> > > > +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> > > > +#else
> > > > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > > > + size_t page_count)
> > > > +{
> > > > + return ERR_PTR(-EINVAL);
> > > > +}
> > > > +EXPORT_SYMBOL_GPL(tee_shm_alloc_dma_mem);
> > > > +#endif
> > > > +
> > > > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> > > > int (*shm_register)(struct tee_context *ctx,
> > > > struct tee_shm *shm,
> > > > diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h
> > > > index f17710196c4c..e46a53e753af 100644
> > > > --- a/include/linux/tee_core.h
> > > > +++ b/include/linux/tee_core.h
> > > > @@ -29,6 +29,8 @@
> > > > #define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */
> > > > #define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */
> > > > #define TEE_SHM_DMA_BUF BIT(4) /* Memory with dma-buf handle */
> > > > +#define TEE_SHM_DMA_MEM BIT(5) /* Memory allocated with */
> > > > + /* dma_alloc_pages() */
> > > >
> > > > #define TEE_DEVICE_FLAG_REGISTERED 0x1
> > > > #define TEE_MAX_DEV_NAME_LEN 32
> > > > @@ -310,6 +312,9 @@ void *tee_get_drvdata(struct tee_device *teedev);
> > > > */
> > > > struct tee_shm *tee_shm_alloc_priv_buf(struct tee_context *ctx, size_t size);
> > > >
> > > > +struct tee_shm *tee_shm_alloc_dma_mem(struct tee_context *ctx,
> > > > + size_t page_count);
> > > > +
> > > > int tee_dyn_shm_alloc_helper(struct tee_shm *shm, size_t size, size_t align,
> > > > int (*shm_register)(struct tee_context *ctx,
> > > > struct tee_shm *shm,
> > > > --
> > > > 2.43.0
> > > >
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