Re: [PATCH] dma-buf: support 32bit DMA_BUF_SET_NAME ioctl

From: Sumit Semwal
Date: Tue Apr 07 2020 - 09:26:40 EST


Hello,

Daniel, your comments here, please?

On Mon, 24 Feb 2020 at 09:09, Martin Liu <liumartin@xxxxxxxxxx> wrote:
>
> On Tue, Jan 14, 2020 at 09:41:01PM +0800, Martin Liu wrote:
>
> CC more MLs for winder review.
>
> > This commit adds SET_NAME ioctl coversion to
> > support 32 bit ioctl.
> >
> > Signed-off-by: Martin Liu <liumartin@xxxxxxxxxx>
> > ---
> > drivers/dma-buf/dma-buf.c | 22 +++++++++++++++++++++-
> > 1 file changed, 21 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
> > index ce41cd9b758a..a73048b34843 100644
> > --- a/drivers/dma-buf/dma-buf.c
> > +++ b/drivers/dma-buf/dma-buf.c
> > @@ -25,6 +25,7 @@
> > #include <linux/mm.h>
> > #include <linux/mount.h>
> > #include <linux/pseudo_fs.h>
> > +#include <linux/compat.h>
> >
> > #include <uapi/linux/dma-buf.h>
> > #include <uapi/linux/magic.h>
> > @@ -409,13 +410,32 @@ static void dma_buf_show_fdinfo(struct seq_file *m, struct file *file)
> > dma_resv_unlock(dmabuf->resv);
> > }
> >
> > +#ifdef CONFIG_COMPAT
> > +static long dma_buf_ioctl_compat(struct file *file, unsigned int cmd,
> > + unsigned long arg)
> > +{
> > + switch (_IOC_NR(cmd)) {
> > + case _IOC_NR(DMA_BUF_SET_NAME):
> > + /* Fix up pointer size*/
> > + if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) {
> > + cmd &= ~IOCSIZE_MASK;
> > + cmd |= sizeof(void *) << IOCSIZE_SHIFT;
> > + }
> > + break;
> > + }
> > + return dma_buf_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
> > +}
> > +#endif
> > +
> > static const struct file_operations dma_buf_fops = {
> > .release = dma_buf_release,
> > .mmap = dma_buf_mmap_internal,
> > .llseek = dma_buf_llseek,
> > .poll = dma_buf_poll,
> > .unlocked_ioctl = dma_buf_ioctl,
> > - .compat_ioctl = compat_ptr_ioctl,
> > +#ifdef CONFIG_COMPAT
> > + .compat_ioctl = dma_buf_ioctl_compat,
> > +#endif
> > .show_fdinfo = dma_buf_show_fdinfo,
> > };
> >
> > --
> > 2.25.0.rc1.283.g88dfdc4193-goog
> >



--
Thanks and regards,

Sumit Semwal
Linaro Consumer Group - Kernel Team Lead
Linaro.org â Open source software for ARM SoCs