diff options
| author | Dhaval Patel <pdhaval@codeaurora.org> | 2015-11-04 14:01:09 -0800 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-23 20:47:34 -0700 |
| commit | 75af757c1b7ba687c81003b6bf8b424d983447bf (patch) | |
| tree | 3abfb6d926934cef2c2988db51aac49b4e3d0970 /include | |
| parent | e56fc3b5b0bf0e1a1ef39ab5d0a238e5cb3bd3d8 (diff) | |
msm: mdss: pass file pointer as argument to fb_ioctl api
MDSS driver uses file pointer to track the client
and associates the resources based on it. There can
be a race condition between to clients ioctl call
and it can lead to track resources with wrong
caller. This can leads to release/reallocate
resources prematurely to other client which may
show blank screen on display.
One good example client call flow is:
<-step:1-> fb_open by client-X
<-step:2-> fb_open by client-Y
<-step:3-> fb_ioctl by client-X
<-step:4-> fb_ioctl by client-Y
<-step:5-> fb_ioctl by client-X
<-step:6-> fb_close by client-Y
If step-5 and step-6 both are running on two different
CPUs at same time then it may overwrite the file node
unintentionally.
This change tries to pass the file pointer as one of
the argument to IOCTL call. It avoids usage of mutex
lock to support the concurrent calls.
Change-Id: I0bfd76358c80892c8e4f56298bce6c33b4132550
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/fb.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/fb.h b/include/linux/fb.h index 32d82ae5b55f..87942d80a465 100644 --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -288,10 +288,18 @@ struct fb_ops { int (*fb_ioctl)(struct fb_info *info, unsigned int cmd, unsigned long arg); + /* perform fb specific ioctl v2 (optional) - provides file param */ + int (*fb_ioctl_v2)(struct fb_info *info, unsigned int cmd, + unsigned long arg, struct file *file); + /* Handle 32bit compat ioctl (optional) */ int (*fb_compat_ioctl)(struct fb_info *info, unsigned cmd, unsigned long arg); + /* Handle 32bit compat ioctl (optional) */ + int (*fb_compat_ioctl_v2)(struct fb_info *info, unsigned cmd, + unsigned long arg, struct file *file); + /* perform fb specific mmap */ int (*fb_mmap)(struct fb_info *info, struct vm_area_struct *vma); |