Re: [Linaro-mm-sig] [PATCHv4 05/12] staging: android: ion: Break the ABI in the name of forward progress

[Daniel Vetter <daniel@ffwll.ch>]

On Tue, Apr 18, 2017 at 11:27:07AM -0700, Laura Abbott wrote:
> Several of the Ion ioctls were designed in such a way that they
> necessitate compat ioctls. We're breaking a bunch of other ABIs and
> cleaning stuff up anyway so let's follow the ioctl guidelines and clean
> things up while everyone is busy converting things over anyway. As part
> of this, also remove the useless alignment field from the allocation
> structure.
> 
> Signed-off-by: Laura Abbott <labbott@redhat.com>

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

> ---
>  drivers/staging/android/ion/Makefile     |   3 -
>  drivers/staging/android/ion/compat_ion.c | 152 -------------------------------
>  drivers/staging/android/ion/compat_ion.h |  29 ------
>  drivers/staging/android/ion/ion-ioctl.c  |   1 -
>  drivers/staging/android/ion/ion.c        |   5 +-
>  drivers/staging/android/uapi/ion.h       |  19 ++--
>  6 files changed, 11 insertions(+), 198 deletions(-)
>  delete mode 100644 drivers/staging/android/ion/compat_ion.c
>  delete mode 100644 drivers/staging/android/ion/compat_ion.h
> 
> diff --git a/drivers/staging/android/ion/Makefile b/drivers/staging/android/ion/Makefile
> index 66d0c4a..a892afa 100644
> --- a/drivers/staging/android/ion/Makefile
> +++ b/drivers/staging/android/ion/Makefile
> @@ -2,6 +2,3 @@ obj-$(CONFIG_ION) +=	ion.o ion-ioctl.o ion_heap.o \
>  			ion_page_pool.o ion_system_heap.o \
>  			ion_carveout_heap.o ion_chunk_heap.o
>  obj-$(CONFIG_ION_CMA_HEAP) += ion_cma_heap.o
> -ifdef CONFIG_COMPAT
> -obj-$(CONFIG_ION) += compat_ion.o
> -endif
> diff --git a/drivers/staging/android/ion/compat_ion.c b/drivers/staging/android/ion/compat_ion.c
> deleted file mode 100644
> index 5037ddd..0000000
> --- a/drivers/staging/android/ion/compat_ion.c
> +++ /dev/null
> @@ -1,152 +0,0 @@
> -/*
> - * drivers/staging/android/ion/compat_ion.c
> - *
> - * Copyright (C) 2013 Google, Inc.
> - *
> - * This software is licensed under the terms of the GNU General Public
> - * License version 2, as published by the Free Software Foundation, and
> - * may be copied, distributed, and modified under those terms.
> - *
> - * This program is distributed in the hope that it will be useful,
> - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> - * GNU General Public License for more details.
> - *
> - */
> -
> -#include <linux/compat.h>
> -#include <linux/fs.h>
> -#include <linux/uaccess.h>
> -
> -#include "ion.h"
> -#include "compat_ion.h"
> -
> -/* See drivers/staging/android/uapi/ion.h for the definition of these structs */
> -struct compat_ion_allocation_data {
> -	compat_size_t len;
> -	compat_size_t align;
> -	compat_uint_t heap_id_mask;
> -	compat_uint_t flags;
> -	compat_int_t handle;
> -};
> -
> -struct compat_ion_handle_data {
> -	compat_int_t handle;
> -};
> -
> -#define COMPAT_ION_IOC_ALLOC	_IOWR(ION_IOC_MAGIC, 0, \
> -				      struct compat_ion_allocation_data)
> -#define COMPAT_ION_IOC_FREE	_IOWR(ION_IOC_MAGIC, 1, \
> -				      struct compat_ion_handle_data)
> -
> -static int compat_get_ion_allocation_data(
> -			struct compat_ion_allocation_data __user *data32,
> -			struct ion_allocation_data __user *data)
> -{
> -	compat_size_t s;
> -	compat_uint_t u;
> -	compat_int_t i;
> -	int err;
> -
> -	err = get_user(s, &data32->len);
> -	err |= put_user(s, &data->len);
> -	err |= get_user(s, &data32->align);
> -	err |= put_user(s, &data->align);
> -	err |= get_user(u, &data32->heap_id_mask);
> -	err |= put_user(u, &data->heap_id_mask);
> -	err |= get_user(u, &data32->flags);
> -	err |= put_user(u, &data->flags);
> -	err |= get_user(i, &data32->handle);
> -	err |= put_user(i, &data->handle);
> -
> -	return err;
> -}
> -
> -static int compat_get_ion_handle_data(
> -			struct compat_ion_handle_data __user *data32,
> -			struct ion_handle_data __user *data)
> -{
> -	compat_int_t i;
> -	int err;
> -
> -	err = get_user(i, &data32->handle);
> -	err |= put_user(i, &data->handle);
> -
> -	return err;
> -}
> -
> -static int compat_put_ion_allocation_data(
> -			struct compat_ion_allocation_data __user *data32,
> -			struct ion_allocation_data __user *data)
> -{
> -	compat_size_t s;
> -	compat_uint_t u;
> -	compat_int_t i;
> -	int err;
> -
> -	err = get_user(s, &data->len);
> -	err |= put_user(s, &data32->len);
> -	err |= get_user(s, &data->align);
> -	err |= put_user(s, &data32->align);
> -	err |= get_user(u, &data->heap_id_mask);
> -	err |= put_user(u, &data32->heap_id_mask);
> -	err |= get_user(u, &data->flags);
> -	err |= put_user(u, &data32->flags);
> -	err |= get_user(i, &data->handle);
> -	err |= put_user(i, &data32->handle);
> -
> -	return err;
> -}
> -
> -long compat_ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> -{
> -	long ret;
> -
> -	if (!filp->f_op->unlocked_ioctl)
> -		return -ENOTTY;
> -
> -	switch (cmd) {
> -	case COMPAT_ION_IOC_ALLOC:
> -	{
> -		struct compat_ion_allocation_data __user *data32;
> -		struct ion_allocation_data __user *data;
> -		int err;
> -
> -		data32 = compat_ptr(arg);
> -		data = compat_alloc_user_space(sizeof(*data));
> -		if (!data)
> -			return -EFAULT;
> -
> -		err = compat_get_ion_allocation_data(data32, data);
> -		if (err)
> -			return err;
> -		ret = filp->f_op->unlocked_ioctl(filp, ION_IOC_ALLOC,
> -							(unsigned long)data);
> -		err = compat_put_ion_allocation_data(data32, data);
> -		return ret ? ret : err;
> -	}
> -	case COMPAT_ION_IOC_FREE:
> -	{
> -		struct compat_ion_handle_data __user *data32;
> -		struct ion_handle_data __user *data;
> -		int err;
> -
> -		data32 = compat_ptr(arg);
> -		data = compat_alloc_user_space(sizeof(*data));
> -		if (!data)
> -			return -EFAULT;
> -
> -		err = compat_get_ion_handle_data(data32, data);
> -		if (err)
> -			return err;
> -
> -		return filp->f_op->unlocked_ioctl(filp, ION_IOC_FREE,
> -							(unsigned long)data);
> -	}
> -	case ION_IOC_SHARE:
> -		return filp->f_op->unlocked_ioctl(filp, cmd,
> -						(unsigned long)compat_ptr(arg));
> -	default:
> -		return -ENOIOCTLCMD;
> -	}
> -}
> diff --git a/drivers/staging/android/ion/compat_ion.h b/drivers/staging/android/ion/compat_ion.h
> deleted file mode 100644
> index 9da8f91..0000000
> --- a/drivers/staging/android/ion/compat_ion.h
> +++ /dev/null
> @@ -1,29 +0,0 @@
> -/*
> - * drivers/staging/android/ion/compat_ion.h
> - *
> - * Copyright (C) 2013 Google, Inc.
> - *
> - * This software is licensed under the terms of the GNU General Public
> - * License version 2, as published by the Free Software Foundation, and
> - * may be copied, distributed, and modified under those terms.
> - *
> - * This program is distributed in the hope that it will be useful,
> - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> - * GNU General Public License for more details.
> - *
> - */
> -
> -#ifndef _LINUX_COMPAT_ION_H
> -#define _LINUX_COMPAT_ION_H
> -
> -#if IS_ENABLED(CONFIG_COMPAT)
> -
> -long compat_ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
> -
> -#else
> -
> -#define compat_ion_ioctl  NULL
> -
> -#endif /* CONFIG_COMPAT */
> -#endif /* _LINUX_COMPAT_ION_H */
> diff --git a/drivers/staging/android/ion/ion-ioctl.c b/drivers/staging/android/ion/ion-ioctl.c
> index a361724..91b5c2b 100644
> --- a/drivers/staging/android/ion/ion-ioctl.c
> +++ b/drivers/staging/android/ion/ion-ioctl.c
> @@ -20,7 +20,6 @@
>  
>  #include "ion.h"
>  #include "ion_priv.h"
> -#include "compat_ion.h"
>  
>  union ion_ioctl_arg {
>  	struct ion_fd_data fd;
> diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
> index 65638f5..fbab1e3 100644
> --- a/drivers/staging/android/ion/ion.c
> +++ b/drivers/staging/android/ion/ion.c
> @@ -40,7 +40,6 @@
>  
>  #include "ion.h"
>  #include "ion_priv.h"
> -#include "compat_ion.h"
>  
>  bool ion_buffer_cached(struct ion_buffer *buffer)
>  {
> @@ -1065,7 +1064,9 @@ static const struct file_operations ion_fops = {
>  	.open           = ion_open,
>  	.release        = ion_release,
>  	.unlocked_ioctl = ion_ioctl,
> -	.compat_ioctl   = compat_ion_ioctl,
> +#ifdef CONFIG_COMPAT
> +	.compat_ioctl	= ion_ioctl,
> +#endif
>  };
>  
>  static size_t ion_debug_heap_total(struct ion_client *client,
> diff --git a/drivers/staging/android/uapi/ion.h b/drivers/staging/android/uapi/ion.h
> index abd72fd..bba1c47 100644
> --- a/drivers/staging/android/uapi/ion.h
> +++ b/drivers/staging/android/uapi/ion.h
> @@ -20,8 +20,6 @@
>  #include <linux/ioctl.h>
>  #include <linux/types.h>
>  
> -typedef int ion_user_handle_t;
> -
>  /**
>   * enum ion_heap_types - list of all possible types of heaps
>   * @ION_HEAP_TYPE_SYSTEM:	 memory allocated via vmalloc
> @@ -76,7 +74,6 @@ enum ion_heap_type {
>  /**
>   * struct ion_allocation_data - metadata passed from userspace for allocations
>   * @len:		size of the allocation
> - * @align:		required alignment of the allocation
>   * @heap_id_mask:	mask of heap ids to allocate from
>   * @flags:		flags passed to heap
>   * @handle:		pointer that will be populated with a cookie to use to
> @@ -85,11 +82,11 @@ enum ion_heap_type {
>   * Provided by userspace as an argument to the ioctl
>   */
>  struct ion_allocation_data {
> -	size_t len;
> -	size_t align;
> -	unsigned int heap_id_mask;
> -	unsigned int flags;
> -	ion_user_handle_t handle;
> +	__u64 len;
> +	__u32 heap_id_mask;
> +	__u32 flags;
> +	__u32 handle;
> +	__u32 unused;
>  };
>  
>  /**
> @@ -103,8 +100,8 @@ struct ion_allocation_data {
>   * provides the file descriptor and the kernel returns the handle.
>   */
>  struct ion_fd_data {
> -	ion_user_handle_t handle;
> -	int fd;
> +	__u32 handle;
> +	__u32 fd;
>  };
>  
>  /**
> @@ -112,7 +109,7 @@ struct ion_fd_data {
>   * @handle:	a handle
>   */
>  struct ion_handle_data {
> -	ion_user_handle_t handle;
> +	__u32 handle;
>  };
>  
>  #define MAX_HEAP_NAME			32
> -- 
> 2.7.4
> 
> _______________________________________________
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> Linaro-mm-sig@lists.linaro.org
> https://lists.linaro.org/mailman/listinfo/linaro-mm-sig

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

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