[xserver] prime: clean up slave bo properly. (v3)

[Hans de Goede]

Hi,

On 06-05-16 02:46, Dave Airlie wrote:
> This is an ABI break, in that we now pass NULL to a function
> that hasn't accepted it before.

s/NULL/-1/

> Alex Goins had a different patch for this but it wasn't symmetrical,
> it freed something in a very different place than it allocated it,
> this attempts to retain symmetry in the releasing of the backing bo.

I can confirm that this fixes a resource leak when using a slave-output,
with this fix + the gbm fix I send to the mesa-list I can actually
unload the udl kernel module after unplugging an usb-2 displaylink
device.

This patch is:

Tested-by: Hans de Goede <hdegoede at redhat.com>

And with the commit msg fixed it also is:

Reviewed-by: Hans de Goede <hdegoede at redhat.com>

Regards,

Hans


>
> v2: use a new toplevel API, though it still passes NULL to something
> that wasn't expecting it.
> v3: pass -1 instead of 0.
>
> Signed-off-by: Dave Airlie <airlied at redhat.com>
> ---
>  dix/pixmap.c                                     | 7 +++++++
>  hw/xfree86/dri2/dri2.c                           | 1 +
>  hw/xfree86/drivers/modesetting/driver.c          | 4 ++++
>  hw/xfree86/drivers/modesetting/drmmode_display.c | 6 ++++++
>  include/pixmap.h                                 | 3 +++
>  randr/rrcrtc.c                                   | 2 ++
>  6 files changed, 23 insertions(+)
>
> diff --git a/dix/pixmap.c b/dix/pixmap.c
> index 11d83fe..49267a1 100644
> --- a/dix/pixmap.c
> +++ b/dix/pixmap.c
> @@ -132,6 +132,13 @@ FreePixmap(PixmapPtr pPixmap)
>      free(pPixmap);
>  }
>
> +void PixmapUnshareSlavePixmap(PixmapPtr slave_pixmap)
> +{
> +     int ihandle = -1;
> +     ScreenPtr pScreen = slave_pixmap->drawable.pScreen;
> +     pScreen->SetSharedPixmapBacking(slave_pixmap, ((void *)(long)ihandle));
> +}
> +
>  PixmapPtr PixmapShareToSlave(PixmapPtr pixmap, ScreenPtr slave)
>  {
>      PixmapPtr spix;
> diff --git a/hw/xfree86/dri2/dri2.c b/hw/xfree86/dri2/dri2.c
> index d55be19..f80599f 100644
> --- a/hw/xfree86/dri2/dri2.c
> +++ b/hw/xfree86/dri2/dri2.c
> @@ -859,6 +859,7 @@ DrawablePtr DRI2UpdatePrime(DrawablePtr pDraw, DRI2BufferPtr pDest)
>          if (pPriv->prime_slave_pixmap->master_pixmap == mpix)
>              return &pPriv->prime_slave_pixmap->drawable;
>          else {
> +            PixmapUnshareSlavePixmap(pPriv->prime_slave_pixmap);
>              (*pPriv->prime_slave_pixmap->master_pixmap->drawable.pScreen->DestroyPixmap)(pPriv->prime_slave_pixmap->master_pixmap);
>              (*slave->DestroyPixmap)(pPriv->prime_slave_pixmap);
>              pPriv->prime_slave_pixmap = NULL;
> diff --git a/hw/xfree86/drivers/modesetting/driver.c b/hw/xfree86/drivers/modesetting/driver.c
> index cd59c06..1604044 100644
> --- a/hw/xfree86/drivers/modesetting/driver.c
> +++ b/hw/xfree86/drivers/modesetting/driver.c
> @@ -1074,6 +1074,10 @@ msSetSharedPixmapBacking(PixmapPtr ppix, void *fd_handle)
>      Bool ret;
>      int ihandle = (int) (long) fd_handle;
>
> +    if (ihandle == -1)
> +        if (!ms->drmmode.reverse_prime_offload_mode)
> +           return drmmode_SetSlaveBO(ppix, &ms->drmmode, ihandle, 0, 0);
> +
>      if (ms->drmmode.reverse_prime_offload_mode) {
>          ret = glamor_back_pixmap_from_fd(ppix, ihandle,
>                                           ppix->drawable.width,
> diff --git a/hw/xfree86/drivers/modesetting/drmmode_display.c b/hw/xfree86/drivers/modesetting/drmmode_display.c
> index 2cda523..5e104b8 100644
> --- a/hw/xfree86/drivers/modesetting/drmmode_display.c
> +++ b/hw/xfree86/drivers/modesetting/drmmode_display.c
> @@ -214,6 +214,12 @@ drmmode_SetSlaveBO(PixmapPtr ppix,
>  {
>      msPixmapPrivPtr ppriv = msGetPixmapPriv(drmmode, ppix);
>
> +    if (fd_handle == -1) {
> +        dumb_bo_destroy(drmmode->fd, ppriv->backing_bo);
> +        ppriv->backing_bo = NULL;
> +        return TRUE;
> +    }
> +
>      ppriv->backing_bo =
>          dumb_get_bo_from_fd(drmmode->fd, fd_handle, pitch, size);
>      if (!ppriv->backing_bo)
> diff --git a/include/pixmap.h b/include/pixmap.h
> index c6a7736..86b513d 100644
> --- a/include/pixmap.h
> +++ b/include/pixmap.h
> @@ -115,6 +115,9 @@ extern _X_EXPORT void FreePixmap(PixmapPtr /*pPixmap */ );
>  extern _X_EXPORT PixmapPtr
>  PixmapShareToSlave(PixmapPtr pixmap, ScreenPtr slave);
>
> +extern _X_EXPORT void
> +PixmapUnshareSlavePixmap(PixmapPtr slave_pixmap);
> +
>  #define HAS_DIRTYTRACKING_ROTATION 1
>  extern _X_EXPORT Bool
>  PixmapStartDirtyTracking(PixmapPtr src,
> diff --git a/randr/rrcrtc.c b/randr/rrcrtc.c
> index 566a3db..5447133 100644
> --- a/randr/rrcrtc.c
> +++ b/randr/rrcrtc.c
> @@ -373,6 +373,8 @@ rrDestroySharedPixmap(RRCrtcPtr crtc, PixmapPtr pPixmap) {
>           * Unref the pixmap twice: once for the original reference, and once
>           * for the reference implicitly added by PixmapShareToSlave.
>           */
> +        PixmapUnshareSlavePixmap(pPixmap);
> +
>          master->DestroyPixmap(pPixmap->master_pixmap);
>          master->DestroyPixmap(pPixmap->master_pixmap);
>      }
>