DRM drivers share a common address_space across all character-devices of a single DRM device. This allows simple buffer eviction and mapping-control. However, DRM core currently waits for the first ->open() on any char-dev to mark the underlying inode as backing inode of the device. This delayed initialization causes ugly conditions all over the place: if (dev->dev_mapping) do_sth();
To avoid delayed initialization and to stop reusing the inode of the char-dev, we allocate an anonymous inode for each DRM device and reset filp->f_mapping to it on ->open().
Signed-off-by: David Herrmann dh.herrmann@gmail.com --- drivers/gpu/drm/ast/ast_ttm.c | 2 +- drivers/gpu/drm/cirrus/cirrus_ttm.c | 2 +- drivers/gpu/drm/drm_fops.c | 25 +++---------------------- drivers/gpu/drm/drm_stub.c | 12 +++++++++++- drivers/gpu/drm/i915/i915_gem.c | 3 ++- drivers/gpu/drm/mgag200/mgag200_ttm.c | 2 +- drivers/gpu/drm/nouveau/nouveau_gem.c | 2 +- drivers/gpu/drm/omapdrm/omap_gem.c | 34 +++++++++++++++++----------------- drivers/gpu/drm/qxl/qxl_object.c | 3 +-- drivers/gpu/drm/qxl/qxl_ttm.c | 3 +-- drivers/gpu/drm/radeon/radeon_object.c | 2 +- drivers/gpu/drm/radeon/radeon_ttm.c | 2 +- drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 2 +- include/drm/drmP.h | 2 +- 14 files changed, 43 insertions(+), 53 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_ttm.c b/drivers/gpu/drm/ast/ast_ttm.c index 4ea9b17..2b49153 100644 --- a/drivers/gpu/drm/ast/ast_ttm.c +++ b/drivers/gpu/drm/ast/ast_ttm.c @@ -324,7 +324,7 @@ int ast_bo_create(struct drm_device *dev, int size, int align, }
astbo->bo.bdev = &ast->ttm.bdev; - astbo->bo.bdev->dev_mapping = dev->dev_mapping; + astbo->bo.bdev->dev_mapping = dev->anon_inode->i_mapping;
ast_ttm_placement(astbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);
diff --git a/drivers/gpu/drm/cirrus/cirrus_ttm.c b/drivers/gpu/drm/cirrus/cirrus_ttm.c index 8b37c25..efcbd70 100644 --- a/drivers/gpu/drm/cirrus/cirrus_ttm.c +++ b/drivers/gpu/drm/cirrus/cirrus_ttm.c @@ -329,7 +329,7 @@ int cirrus_bo_create(struct drm_device *dev, int size, int align, }
cirrusbo->bo.bdev = &cirrus->ttm.bdev; - cirrusbo->bo.bdev->dev_mapping = dev->dev_mapping; + cirrusbo->bo.bdev->dev_mapping = dev->anon_inode->i_mapping;
cirrus_ttm_placement(cirrusbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index 7f2af9a..147a84d 100644 --- a/drivers/gpu/drm/drm_fops.c +++ b/drivers/gpu/drm/drm_fops.c @@ -84,8 +84,6 @@ int drm_open(struct inode *inode, struct file *filp) struct drm_minor *minor; int retcode = 0; int need_setup = 0; - struct address_space *old_mapping; - struct address_space *old_imapping;
minor = idr_find(&drm_minors_idr, minor_id); if (!minor) @@ -99,16 +97,9 @@ int drm_open(struct inode *inode, struct file *filp)
if (!dev->open_count++) need_setup = 1; - mutex_lock(&dev->struct_mutex); - old_imapping = inode->i_mapping; - old_mapping = dev->dev_mapping; - if (old_mapping == NULL) - dev->dev_mapping = &inode->i_data; - /* ihold ensures nobody can remove inode with our i_data */ - ihold(container_of(dev->dev_mapping, struct inode, i_data)); - inode->i_mapping = dev->dev_mapping; - filp->f_mapping = dev->dev_mapping; - mutex_unlock(&dev->struct_mutex); + + /* share address_space across all char-devs of a single device */ + filp->f_mapping = dev->anon_inode->i_mapping;
retcode = drm_open_helper(inode, filp, dev); if (retcode) @@ -121,12 +112,6 @@ int drm_open(struct inode *inode, struct file *filp) return 0;
err_undo: - mutex_lock(&dev->struct_mutex); - filp->f_mapping = old_imapping; - inode->i_mapping = old_imapping; - iput(container_of(dev->dev_mapping, struct inode, i_data)); - dev->dev_mapping = old_mapping; - mutex_unlock(&dev->struct_mutex); dev->open_count--; return retcode; } @@ -434,7 +419,6 @@ int drm_lastclose(struct drm_device * dev)
drm_legacy_dma_takedown(dev);
- dev->dev_mapping = NULL; mutex_unlock(&dev->struct_mutex);
drm_legacy_dev_reinit(dev); @@ -549,9 +533,6 @@ int drm_release(struct inode *inode, struct file *filp) } }
- BUG_ON(dev->dev_mapping == NULL); - iput(container_of(dev->dev_mapping, struct inode, i_data)); - /* drop the reference held my the file priv */ if (file_priv->master) drm_master_put(&file_priv->master); diff --git a/drivers/gpu/drm/drm_stub.c b/drivers/gpu/drm/drm_stub.c index f2903d7..04c25ce 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -526,8 +526,15 @@ struct drm_device *drm_dev_alloc(struct drm_driver *driver, mutex_init(&dev->struct_mutex); mutex_init(&dev->ctxlist_mutex);
- if (drm_ht_create(&dev->map_hash, 12)) + dev->anon_inode = drm_fs_inode_new(); + if (IS_ERR(dev->anon_inode)) { + ret = PTR_ERR(dev->anon_inode); + DRM_ERROR("Cannot allocate anonymous inode: %d\n", ret); goto err_free; + } + + if (drm_ht_create(&dev->map_hash, 12)) + goto err_inode;
ret = drm_ctxbitmap_init(dev); if (ret) { @@ -549,6 +556,8 @@ err_ctxbitmap: drm_ctxbitmap_cleanup(dev); err_ht: drm_ht_remove(&dev->map_hash); +err_inode: + drm_fs_inode_free(dev->anon_inode); err_free: kfree(dev); return NULL; @@ -576,6 +585,7 @@ void drm_dev_free(struct drm_device *dev)
drm_ctxbitmap_cleanup(dev); drm_ht_remove(&dev->map_hash); + drm_fs_inode_free(dev->anon_inode);
kfree(dev->devname); kfree(dev); diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 32636a4..365e248 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1501,7 +1501,8 @@ i915_gem_release_mmap(struct drm_i915_gem_object *obj) if (!obj->fault_mappable) return;
- drm_vma_node_unmap(&obj->base.vma_node, obj->base.dev->dev_mapping); + drm_vma_node_unmap(&obj->base.vma_node, + obj->base.dev->anon_inode->i_mapping); obj->fault_mappable = false; }
diff --git a/drivers/gpu/drm/mgag200/mgag200_ttm.c b/drivers/gpu/drm/mgag200/mgag200_ttm.c index adb5166..c1c2cb6 100644 --- a/drivers/gpu/drm/mgag200/mgag200_ttm.c +++ b/drivers/gpu/drm/mgag200/mgag200_ttm.c @@ -324,7 +324,7 @@ int mgag200_bo_create(struct drm_device *dev, int size, int align, }
mgabo->bo.bdev = &mdev->ttm.bdev; - mgabo->bo.bdev->dev_mapping = dev->dev_mapping; + mgabo->bo.bdev->dev_mapping = dev->anon_inode->i_mapping;
mgag200_ttm_placement(mgabo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);
diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c index 27c3fd8..5b193b8 100644 --- a/drivers/gpu/drm/nouveau/nouveau_gem.c +++ b/drivers/gpu/drm/nouveau/nouveau_gem.c @@ -228,7 +228,7 @@ nouveau_gem_ioctl_new(struct drm_device *dev, void *data, struct nouveau_bo *nvbo = NULL; int ret = 0;
- drm->ttm.bdev.dev_mapping = drm->dev->dev_mapping; + drm->ttm.bdev.dev_mapping = drm->dev->anon_inode->i_mapping;
if (!pfb->memtype_valid(pfb, req->info.tile_flags)) { NV_ERROR(cli, "bad page flags: 0x%08x\n", req->info.tile_flags); diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c index 5aec3e8..c8d9727 100644 --- a/drivers/gpu/drm/omapdrm/omap_gem.c +++ b/drivers/gpu/drm/omapdrm/omap_gem.c @@ -153,24 +153,24 @@ static struct { static void evict_entry(struct drm_gem_object *obj, enum tiler_fmt fmt, struct usergart_entry *entry) { - if (obj->dev->dev_mapping) { - struct omap_gem_object *omap_obj = to_omap_bo(obj); - int n = usergart[fmt].height; - size_t size = PAGE_SIZE * n; - loff_t off = mmap_offset(obj) + - (entry->obj_pgoff << PAGE_SHIFT); - const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE); - if (m > 1) { - int i; - /* if stride > than PAGE_SIZE then sparse mapping: */ - for (i = n; i > 0; i--) { - unmap_mapping_range(obj->dev->dev_mapping, - off, PAGE_SIZE, 1); - off += PAGE_SIZE * m; - } - } else { - unmap_mapping_range(obj->dev->dev_mapping, off, size, 1); + struct omap_gem_object *omap_obj = to_omap_bo(obj); + int n = usergart[fmt].height; + size_t size = PAGE_SIZE * n; + loff_t off = mmap_offset(obj) + + (entry->obj_pgoff << PAGE_SHIFT); + const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE); + + if (m > 1) { + int i; + /* if stride > than PAGE_SIZE then sparse mapping: */ + for (i = n; i > 0; i--) { + unmap_mapping_range(obj->dev->anon_inode->i_mapping, + off, PAGE_SIZE, 1); + off += PAGE_SIZE * m; } + } else { + unmap_mapping_range(obj->dev->anon_inode->i_mapping, + off, size, 1); }
entry->obj = NULL; diff --git a/drivers/gpu/drm/qxl/qxl_object.c b/drivers/gpu/drm/qxl/qxl_object.c index 8691c76..7e20c21 100644 --- a/drivers/gpu/drm/qxl/qxl_object.c +++ b/drivers/gpu/drm/qxl/qxl_object.c @@ -82,8 +82,7 @@ int qxl_bo_create(struct qxl_device *qdev, enum ttm_bo_type type; int r;
- if (unlikely(qdev->mman.bdev.dev_mapping == NULL)) - qdev->mman.bdev.dev_mapping = qdev->ddev->dev_mapping; + qdev->mman.bdev.dev_mapping = qdev->ddev->anon_inode->i_mapping; if (kernel) type = ttm_bo_type_kernel; else diff --git a/drivers/gpu/drm/qxl/qxl_ttm.c b/drivers/gpu/drm/qxl/qxl_ttm.c index c7e7e65..78cbc40 100644 --- a/drivers/gpu/drm/qxl/qxl_ttm.c +++ b/drivers/gpu/drm/qxl/qxl_ttm.c @@ -518,8 +518,7 @@ int qxl_ttm_init(struct qxl_device *qdev) ((unsigned)num_io_pages * PAGE_SIZE) / (1024 * 1024)); DRM_INFO("qxl: %uM of Surface memory size\n", (unsigned)qdev->surfaceram_size / (1024 * 1024)); - if (unlikely(qdev->mman.bdev.dev_mapping == NULL)) - qdev->mman.bdev.dev_mapping = qdev->ddev->dev_mapping; + qdev->mman.bdev.dev_mapping = qdev->ddev->anon_inode->i_mapping; r = qxl_ttm_debugfs_init(qdev); if (r) { DRM_ERROR("Failed to init debugfs\n"); diff --git a/drivers/gpu/drm/radeon/radeon_object.c b/drivers/gpu/drm/radeon/radeon_object.c index 08595cf..92406ce 100644 --- a/drivers/gpu/drm/radeon/radeon_object.c +++ b/drivers/gpu/drm/radeon/radeon_object.c @@ -120,7 +120,7 @@ int radeon_bo_create(struct radeon_device *rdev,
size = ALIGN(size, PAGE_SIZE);
- rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping; + rdev->mman.bdev.dev_mapping = rdev->ddev->anon_inode->i_mapping; if (kernel) { type = ttm_bo_type_kernel; } else if (sg) { diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c index 77f5b0c..9409575 100644 --- a/drivers/gpu/drm/radeon/radeon_ttm.c +++ b/drivers/gpu/drm/radeon/radeon_ttm.c @@ -739,7 +739,7 @@ int radeon_ttm_init(struct radeon_device *rdev) } DRM_INFO("radeon: %uM of GTT memory ready.\n", (unsigned)(rdev->mc.gtt_size / (1024 * 1024))); - rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping; + rdev->mman.bdev.dev_mapping = rdev->ddev->anon_inode->i_mapping;
r = radeon_ttm_debugfs_init(rdev); if (r) { diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c index 9893328..417d542 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c @@ -961,7 +961,7 @@ static int vmw_driver_open(struct drm_device *dev, struct drm_file *file_priv) goto out_no_tfile;
file_priv->driver_priv = vmw_fp; - dev_priv->bdev.dev_mapping = dev->dev_mapping; + dev_priv->bdev.dev_mapping = dev->anon_inode->i_mapping;
return 0;
diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 04086c5..1aa312a 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1180,7 +1180,7 @@ struct drm_device { struct drm_sg_mem *sg; /**< Scatter gather memory */ unsigned int num_crtcs; /**< Number of CRTCs on this device */ void *dev_private; /**< device private data */ - struct address_space *dev_mapping; + struct inode *anon_inode; struct drm_sigdata sigdata; /**< For block_all_signals */ sigset_t sigmask;