ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 20:51:03 +02:00
Code Issues Packages Projects Releases Wiki Activity

media: v4l2: prepare compat-ioctl rework

Browse Source 
The v4l2-compat-ioctl32() currently takes an extra round trip through user
space pointers when converting the data structure formats. In particular,
this involves using the compat_alloc_user_space() and copy_in_user()
helpers that often lead to worse compat handlers compared to using
in_compat_syscall() checks when copying the data.

The native implementation already gained a simpler method to deal with
the conversion for the time32 conversion.  Hook into the same places to
provide a location for reading and writing user space data from inside
of the generic video_usercopy() helper.

Hans Verkuil rewrote the video_get_user() function here to simplify
the zeroing of the extra input fields and fixed a couple of bugs in
the original implementation.

[hverkuil: fix: CHECK: Please don't use multiple blank lines]

Co-developed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Arnd Bergmann
2020-10-30 17:55:22 +01:00
committed by Mauro Carvalho Chehab
parent 3650b228f8
commit 8dbcc3fa38
3 changed files with 154 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
include/media/v4l2-ioctl.h
View File

@@ -686,6 +686,16 @@ long int v4l2_compat_ioctl32(struct file *file, unsigned int cmd,
unsigned long arg);
#endif
unsigned int v4l2_compat_translate_cmd(unsigned int cmd);
int v4l2_compat_get_user(void __user *arg, void *parg, unsigned int cmd);
int v4l2_compat_put_user(void __user *arg, void *parg, unsigned int cmd);
int v4l2_compat_get_array_args(struct file *file, void *mbuf,
void __user *user_ptr, size_t array_size,
unsigned int cmd, void *arg);
int v4l2_compat_put_array_args(struct file *file, void __user *user_ptr,
void *mbuf, size_t array_size,
unsigned int cmd, void *arg);
/**
* typedef v4l2_kioctl - Typedef used to pass an ioctl handler.
*