Having a limit of 64 DRM devices is not good enough for modern world
where we have multi-GPU servers, SR-IOV virtual functions and virtual
devices used for testing.
Let's utilize full minor range for DRM devices.
To avoid regressing the existing userspace, we're still maintaining the
numbering scheme where 0-63 is used for primary, 64-127 is reserved
(formerly for control) and 128-191 is used for render.
This is continued for minors >= 192 (192-255 for primary, 256-319
reserved, 320-383 for render, and so on).
Signed-off-by: Michał Winiarski <michal.winiarski@xxxxxxxxx>
---
drivers/gpu/drm/drm_drv.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index 8214a0b1ab7f..b64b5c45cd80 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -113,7 +113,7 @@ static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
{
struct drm_minor *minor;
unsigned long flags;
- int r;
+ int r, start, end;
minor = drmm_kzalloc(dev, sizeof(*minor), GFP_KERNEL);
if (!minor)
@@ -122,15 +122,19 @@ static int drm_minor_alloc(struct drm_device *dev, unsigned int type)
minor->type = type;
minor->dev = dev;
- idr_preload(GFP_KERNEL);
- spin_lock_irqsave(&drm_minor_lock, flags);
- r = idr_alloc(&drm_minors_idr,
- NULL,
- 64 * type,
- 64 * (type + 1),
- GFP_NOWAIT);
- spin_unlock_irqrestore(&drm_minor_lock, flags);
- idr_preload_end();
+ start = 64 * type;
+ end = 64 * (type + 1);
+
+ do {
+ idr_preload(GFP_KERNEL);
+ spin_lock_irqsave(&drm_minor_lock, flags);
+ r = idr_alloc(&drm_minors_idr, NULL, start, end, GFP_NOWAIT);
+ spin_unlock_irqrestore(&drm_minor_lock, flags);
+ idr_preload_end();
+
+ start += 192;
+ end += 192;
+ } while ((r == -ENOSPC) && end <= (1 << MINORBITS));
if (r < 0)
return r;
--
2.37.2
