Re: [PATCH v2 12/12] tee: refactor TEE_SHM_* flags
From: Jens Wiklander
Date: Fri Jan 21 2022 - 02:23:35 EST
On Thu, Jan 20, 2022 at 2:04 PM Sumit Garg <sumit.garg@xxxxxxxxxx> wrote:
>
> On Fri, 14 Jan 2022 at 20:38, Jens Wiklander <jens.wiklander@xxxxxxxxxx> wrote:
> >
> > Removes the redundant TEE_SHM_DMA_BUF, TEE_SHM_EXT_DMA_BUF,
> > TEE_SHM_MAPPED and TEE_SHM_KERNEL_MAPPED flags.
> >
> > Assigns new values to the remaining flags to void gaps.
> >
> > Signed-off-by: Jens Wiklander <jens.wiklander@xxxxxxxxxx>
> > ---
> > drivers/tee/tee_shm.c | 21 ++++++++++-----------
> > include/linux/tee_drv.h | 12 ++++--------
> > 2 files changed, 14 insertions(+), 19 deletions(-)
> >
> > diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c
> > index fe3e5977dd7c..9945bdec086b 100644
> > --- a/drivers/tee/tee_shm.c
> > +++ b/drivers/tee/tee_shm.c
> > @@ -139,8 +139,7 @@ static struct tee_shm *shm_alloc_helper(struct tee_context *ctx, size_t size,
> > */
> > struct tee_shm *tee_shm_alloc_user_buf(struct tee_context *ctx, size_t size)
> > {
> > - u32 flags = TEE_SHM_MAPPED | TEE_SHM_DMA_BUF | TEE_SHM_REGISTER |
> > - TEE_SHM_POOL;
> > + u32 flags = TEE_SHM_REGISTER | TEE_SHM_POOL;
> > struct tee_device *teedev = ctx->teedev;
> > struct tee_shm *shm;
> > void *ret;
> > @@ -186,7 +185,7 @@ EXPORT_SYMBOL_GPL(tee_shm_alloc_user_buf);
> > */
> > struct tee_shm *tee_shm_alloc_kernel_buf(struct tee_context *ctx, size_t size)
> > {
> > - u32 flags = TEE_SHM_MAPPED | TEE_SHM_REGISTER | TEE_SHM_POOL;
> > + u32 flags = TEE_SHM_REGISTER | TEE_SHM_POOL;
> >
> > return shm_alloc_helper(ctx, size, PAGE_SIZE, flags, -1);
> > }
> > @@ -211,7 +210,7 @@ EXPORT_SYMBOL_GPL(tee_shm_alloc_kernel_buf);
> > struct tee_shm *tee_shm_alloc_priv_kernel_buf(struct tee_context *ctx,
> > size_t size)
> > {
> > - u32 flags = TEE_SHM_MAPPED | TEE_SHM_PRIV | TEE_SHM_POOL;
> > + u32 flags = TEE_SHM_PRIV | TEE_SHM_POOL;
> >
> > return shm_alloc_helper(ctx, size, sizeof(long) * 2, flags, -1);
> > }
> > @@ -308,7 +307,7 @@ register_shm_helper(struct tee_context *ctx, unsigned long addr,
> > struct tee_shm *tee_shm_register_user_buf(struct tee_context *ctx,
> > unsigned long addr, size_t length)
> > {
> > - u32 f = TEE_SHM_DMA_BUF | TEE_SHM_USER_MAPPED | TEE_SHM_REGISTER;
> > + u32 f = TEE_SHM_USER_MAPPED | TEE_SHM_REGISTER;
> > struct tee_device *teedev = ctx->teedev;
> > struct tee_shm *shm;
> > void *ret;
> > @@ -354,7 +353,7 @@ EXPORT_SYMBOL_GPL(tee_shm_register_user_buf);
> > struct tee_shm *tee_shm_register_kernel_buf(struct tee_context *ctx,
> > void *addr, size_t length)
> > {
> > - u32 f = TEE_SHM_REGISTER | TEE_SHM_KERNEL_MAPPED;
> > + u32 f = TEE_SHM_REGISTER;
> >
> > return register_shm_helper(ctx, (unsigned long)addr, length, f, -1);
> > }
> > @@ -398,7 +397,7 @@ int tee_shm_get_fd(struct tee_shm *shm)
> > {
> > int fd;
> >
> > - if (!(shm->flags & TEE_SHM_DMA_BUF))
> > + if (shm->id < 0)
> > return -EINVAL;
> >
> > /* matched by tee_shm_put() in tee_shm_op_release() */
> > @@ -428,7 +427,7 @@ EXPORT_SYMBOL_GPL(tee_shm_free);
> > */
> > int tee_shm_va2pa(struct tee_shm *shm, void *va, phys_addr_t *pa)
> > {
> > - if (!(shm->flags & TEE_SHM_MAPPED))
> > + if (!shm->kaddr)
> > return -EINVAL;
> > /* Check that we're in the range of the shm */
> > if ((char *)va < (char *)shm->kaddr)
> > @@ -450,7 +449,7 @@ EXPORT_SYMBOL_GPL(tee_shm_va2pa);
> > */
> > int tee_shm_pa2va(struct tee_shm *shm, phys_addr_t pa, void **va)
> > {
> > - if (!(shm->flags & TEE_SHM_MAPPED))
> > + if (!shm->kaddr)
> > return -EINVAL;
> > /* Check that we're in the range of the shm */
> > if (pa < shm->paddr)
> > @@ -478,7 +477,7 @@ EXPORT_SYMBOL_GPL(tee_shm_pa2va);
> > */
> > void *tee_shm_get_va(struct tee_shm *shm, size_t offs)
> > {
> > - if (!(shm->flags & TEE_SHM_MAPPED))
> > + if (!shm->kaddr)
> > return ERR_PTR(-EINVAL);
> > if (offs >= shm->size)
> > return ERR_PTR(-EINVAL);
> > @@ -553,7 +552,7 @@ void tee_shm_put(struct tee_shm *shm)
> > * the refcount_inc() in tee_shm_get_from_id() never starts
> > * from 0.
> > */
> > - if (shm->flags & TEE_SHM_DMA_BUF)
> > + if (shm->id >= 0)
> > idr_remove(&teedev->idr, shm->id);
> > do_release = true;
> > }
> > diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
> > index e4f32885e273..dcc7a55e1128 100644
> > --- a/include/linux/tee_drv.h
> > +++ b/include/linux/tee_drv.h
> > @@ -20,14 +20,10 @@
> > * specific TEE driver.
> > */
> >
> > -#define TEE_SHM_MAPPED BIT(0) /* Memory mapped by the kernel */
> > -#define TEE_SHM_DMA_BUF BIT(1) /* Memory with dma-buf handle */
> > -#define TEE_SHM_EXT_DMA_BUF BIT(2) /* Memory with dma-buf handle */
> > -#define TEE_SHM_REGISTER BIT(3) /* Memory registered in secure world */
> > -#define TEE_SHM_USER_MAPPED BIT(4) /* Memory mapped in user space */
> > -#define TEE_SHM_POOL BIT(5) /* Memory allocated from pool */
> > -#define TEE_SHM_KERNEL_MAPPED BIT(6) /* Memory mapped in kernel space */
> > -#define TEE_SHM_PRIV BIT(7) /* Memory private to TEE driver */
> > +#define TEE_SHM_REGISTER BIT(0) /* Memory registered in secure world */
>
> TEE_SHM_REGISTER as a flag name seems ambiguous to me when it is being
> used by both types of APIs tee_shm_alloc_* and tee_shm_register_*. Can
> we rename it to TEE_SHM_DYNAMIC instead?
Sure, I'll fix that in v3.
Thanks,
Jens
>
> -Sumit
>
> > +#define TEE_SHM_USER_MAPPED BIT(1) /* Memory mapped in user space */
> > +#define TEE_SHM_POOL BIT(2) /* Memory allocated from pool */
> > +#define TEE_SHM_PRIV BIT(3) /* Memory private to TEE driver */
> >
> > struct device;
> > struct tee_device;
> > --
> > 2.31.1
> >