From: Dave Airlie Date: Mon, 27 Sep 2010 06:17:17 +0000 (+1000) Subject: drm/gem: handlecount isn't really a kref so don't make it one. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=29d08b3efddca628b0360411ab2b85f7b1723f48;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git drm/gem: handlecount isn't really a kref so don't make it one. There were lots of places being inconsistent since handle count looked like a kref but it really wasn't. Fix this my just making handle count an atomic on the object, and have it increase the normal object kref. Now i915/radeon/nouveau drivers can drop the normal reference on userspace object creation, and have the handle hold it. This patch fixes a memory leak or corruption on unload, because the driver had no way of knowing if a handle had been actually added for this object, and the fbcon object needed to know this to clean itself up properly. Reviewed-by: Chris Wilson Signed-off-by: Dave Airlie --- diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 6fe2cd298c12..f7e61be8430a 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -148,7 +148,7 @@ int drm_gem_object_init(struct drm_device *dev, return -ENOMEM; kref_init(&obj->refcount); - kref_init(&obj->handlecount); + atomic_set(&obj->handle_count, 0); obj->size = size; atomic_inc(&dev->object_count); @@ -496,12 +496,8 @@ static void drm_gem_object_ref_bug(struct kref *list_kref) * called before drm_gem_object_free or we'll be touching * freed memory */ -void -drm_gem_object_handle_free(struct kref *kref) +void drm_gem_object_handle_free(struct drm_gem_object *obj) { - struct drm_gem_object *obj = container_of(kref, - struct drm_gem_object, - handlecount); struct drm_device *dev = obj->dev; /* Remove any name for this object */ diff --git a/drivers/gpu/drm/drm_info.c b/drivers/gpu/drm/drm_info.c index 2ef2c7827243..974e970ce3f8 100644 --- a/drivers/gpu/drm/drm_info.c +++ b/drivers/gpu/drm/drm_info.c @@ -255,7 +255,7 @@ int drm_gem_one_name_info(int id, void *ptr, void *data) seq_printf(m, "%6d %8zd %7d %8d\n", obj->name, obj->size, - atomic_read(&obj->handlecount.refcount), + atomic_read(&obj->handle_count), atomic_read(&obj->refcount.refcount)); return 0; } diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index cf4ffbee1c00..4cdf74264ee8 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -136,14 +136,12 @@ i915_gem_create_ioctl(struct drm_device *dev, void *data, return -ENOMEM; ret = drm_gem_handle_create(file_priv, obj, &handle); + /* drop reference from allocate - handle holds it now */ + drm_gem_object_unreference_unlocked(obj); if (ret) { - drm_gem_object_unreference_unlocked(obj); return ret; } - /* Sink the floating reference from kref_init(handlecount) */ - drm_gem_object_handle_unreference_unlocked(obj); - args->handle = handle; return 0; } diff --git a/drivers/gpu/drm/i915/intel_fb.c b/drivers/gpu/drm/i915/intel_fb.c index 7bdc96256bf5..56ad9df2ccb5 100644 --- a/drivers/gpu/drm/i915/intel_fb.c +++ b/drivers/gpu/drm/i915/intel_fb.c @@ -237,8 +237,10 @@ int intel_fbdev_destroy(struct drm_device *dev, drm_fb_helper_fini(&ifbdev->helper); drm_framebuffer_cleanup(&ifb->base); - if (ifb->obj) + if (ifb->obj) { + drm_gem_object_handle_unreference(ifb->obj); drm_gem_object_unreference(ifb->obj); + } return 0; } diff --git a/drivers/gpu/drm/nouveau/nouveau_fbcon.c b/drivers/gpu/drm/nouveau/nouveau_fbcon.c index dbd30b2e43fd..d2047713dc59 100644 --- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c +++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c @@ -352,6 +352,7 @@ nouveau_fbcon_destroy(struct drm_device *dev, struct nouveau_fbdev *nfbdev) if (nouveau_fb->nvbo) { nouveau_bo_unmap(nouveau_fb->nvbo); + drm_gem_object_handle_unreference_unlocked(nouveau_fb->nvbo->gem); drm_gem_object_unreference_unlocked(nouveau_fb->nvbo->gem); nouveau_fb->nvbo = NULL; } diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c index ead7b8fc53fc..19620a6709f5 100644 --- a/drivers/gpu/drm/nouveau/nouveau_gem.c +++ b/drivers/gpu/drm/nouveau/nouveau_gem.c @@ -167,11 +167,9 @@ nouveau_gem_ioctl_new(struct drm_device *dev, void *data, goto out; ret = drm_gem_handle_create(file_priv, nvbo->gem, &req->info.handle); + /* drop reference from allocate - handle holds it now */ + drm_gem_object_unreference_unlocked(nvbo->gem); out: - drm_gem_object_handle_unreference_unlocked(nvbo->gem); - - if (ret) - drm_gem_object_unreference_unlocked(nvbo->gem); return ret; } diff --git a/drivers/gpu/drm/nouveau/nouveau_notifier.c b/drivers/gpu/drm/nouveau/nouveau_notifier.c index 3ec181ff50ce..3c9964a8fbad 100644 --- a/drivers/gpu/drm/nouveau/nouveau_notifier.c +++ b/drivers/gpu/drm/nouveau/nouveau_notifier.c @@ -79,6 +79,7 @@ nouveau_notifier_takedown_channel(struct nouveau_channel *chan) mutex_lock(&dev->struct_mutex); nouveau_bo_unpin(chan->notifier_bo); mutex_unlock(&dev->struct_mutex); + drm_gem_object_handle_unreference_unlocked(chan->notifier_bo->gem); drm_gem_object_unreference_unlocked(chan->notifier_bo->gem); drm_mm_takedown(&chan->notifier_heap); } diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c index 7422f274615a..b92d2f2fcbed 100644 --- a/drivers/gpu/drm/radeon/radeon_display.c +++ b/drivers/gpu/drm/radeon/radeon_display.c @@ -843,8 +843,9 @@ static void radeon_user_framebuffer_destroy(struct drm_framebuffer *fb) { struct radeon_framebuffer *radeon_fb = to_radeon_framebuffer(fb); - if (radeon_fb->obj) + if (radeon_fb->obj) { drm_gem_object_unreference_unlocked(radeon_fb->obj); + } drm_framebuffer_cleanup(fb); kfree(radeon_fb); } diff --git a/drivers/gpu/drm/radeon/radeon_fb.c b/drivers/gpu/drm/radeon/radeon_fb.c index c74a8b20d941..9cdf6a35bc2c 100644 --- a/drivers/gpu/drm/radeon/radeon_fb.c +++ b/drivers/gpu/drm/radeon/radeon_fb.c @@ -94,8 +94,10 @@ static void radeonfb_destroy_pinned_object(struct drm_gem_object *gobj) ret = radeon_bo_reserve(rbo, false); if (likely(ret == 0)) { radeon_bo_kunmap(rbo); + radeon_bo_unpin(rbo); radeon_bo_unreserve(rbo); } + drm_gem_object_handle_unreference(gobj); drm_gem_object_unreference_unlocked(gobj); } @@ -325,8 +327,6 @@ static int radeon_fbdev_destroy(struct drm_device *dev, struct radeon_fbdev *rfb { struct fb_info *info; struct radeon_framebuffer *rfb = &rfbdev->rfb; - struct radeon_bo *rbo; - int r; if (rfbdev->helper.fbdev) { info = rfbdev->helper.fbdev; @@ -338,14 +338,8 @@ static int radeon_fbdev_destroy(struct drm_device *dev, struct radeon_fbdev *rfb } if (rfb->obj) { - rbo = rfb->obj->driver_private; - r = radeon_bo_reserve(rbo, false); - if (likely(r == 0)) { - radeon_bo_kunmap(rbo); - radeon_bo_unpin(rbo); - radeon_bo_unreserve(rbo); - } - drm_gem_object_unreference_unlocked(rfb->obj); + radeonfb_destroy_pinned_object(rfb->obj); + rfb->obj = NULL; } drm_fb_helper_fini(&rfbdev->helper); drm_framebuffer_cleanup(&rfb->base); diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c index c578f265b24c..d1e595d91723 100644 --- a/drivers/gpu/drm/radeon/radeon_gem.c +++ b/drivers/gpu/drm/radeon/radeon_gem.c @@ -201,11 +201,11 @@ int radeon_gem_create_ioctl(struct drm_device *dev, void *data, return r; } r = drm_gem_handle_create(filp, gobj, &handle); + /* drop reference from allocate - handle holds it now */ + drm_gem_object_unreference_unlocked(gobj); if (r) { - drm_gem_object_unreference_unlocked(gobj); return r; } - drm_gem_object_handle_unreference_unlocked(gobj); args->handle = handle; return 0; } diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 774e1d49509b..07e4726a4ee0 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -612,7 +612,7 @@ struct drm_gem_object { struct kref refcount; /** Handle count of this object. Each handle also holds a reference */ - struct kref handlecount; + atomic_t handle_count; /* number of handles on this object */ /** Related drm device */ struct drm_device *dev; @@ -1461,7 +1461,7 @@ struct drm_gem_object *drm_gem_object_alloc(struct drm_device *dev, size_t size); int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size); -void drm_gem_object_handle_free(struct kref *kref); +void drm_gem_object_handle_free(struct drm_gem_object *obj); void drm_gem_vm_open(struct vm_area_struct *vma); void drm_gem_vm_close(struct vm_area_struct *vma); int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma); @@ -1496,7 +1496,7 @@ static inline void drm_gem_object_handle_reference(struct drm_gem_object *obj) { drm_gem_object_reference(obj); - kref_get(&obj->handlecount); + atomic_inc(&obj->handle_count); } static inline void @@ -1505,12 +1505,15 @@ drm_gem_object_handle_unreference(struct drm_gem_object *obj) if (obj == NULL) return; + if (atomic_read(&obj->handle_count) == 0) + return; /* * Must bump handle count first as this may be the last * ref, in which case the object would disappear before we * checked for a name */ - kref_put(&obj->handlecount, drm_gem_object_handle_free); + if (atomic_dec_and_test(&obj->handle_count)) + drm_gem_object_handle_free(obj); drm_gem_object_unreference(obj); } @@ -1520,12 +1523,17 @@ drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj) if (obj == NULL) return; + if (atomic_read(&obj->handle_count) == 0) + return; + /* * Must bump handle count first as this may be the last * ref, in which case the object would disappear before we * checked for a name */ - kref_put(&obj->handlecount, drm_gem_object_handle_free); + + if (atomic_dec_and_test(&obj->handle_count)) + drm_gem_object_handle_free(obj); drm_gem_object_unreference_unlocked(obj); }