Instead of delaying inode initialization until first ->open(), we can use an anonymous inode. This avoids modifying FS internal inode fields and provides us a private address_space right during initialization. Delayed TTM dev_mapping initialization is currently left untouched to keep this simple. But we could now safely provide the address_space during ttm_bo_device_init() instead of delaying until first buffer ->mmap(). Note that this also fixes several bugs: - We currently call iput(container_of(..dev_mapping..)) before drm_lastclose(), but we reset dev_mapping to zero at the end of drm_lastclose(). This fails if dev_mapping points to an address_space other than the current inode and the char-dev got already removed. - We also drop dev_mapping during any drm_lastclose() call. So if user-space still has VMAs to our buffers, we will be unable to unmap them if the next ->firstopen() is on another inode. dev_mapping will then point to a new address_space and we leak mappings that we no longer control. - We ignore inode->i_mapping completely. It is unlikely that a FS uses it to overwrite inode->i_data for char-devs, but it definitely doesn't look very nice to ignore it silently. Tested with nouveau on x86_64. Signed-off-by: David Herrmann <dh.herrmann@xxxxxxxxx> Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> --- drivers/gpu/drm/ast/ast_ttm.c | 2 +- drivers/gpu/drm/cirrus/cirrus_ttm.c | 2 +- drivers/gpu/drm/drm_drv.c | 1 - drivers/gpu/drm/drm_fops.c | 24 +++--------------------- 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 | 7 ++++--- drivers/gpu/drm/qxl/qxl_object.c | 2 +- drivers/gpu/drm/qxl/qxl_ttm.c | 2 +- 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 +- 15 files changed, 30 insertions(+), 37 deletions(-) diff --git a/drivers/gpu/drm/ast/ast_ttm.c b/drivers/gpu/drm/ast/ast_ttm.c index 32aecb3..74eed74 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 75becde..abd401d 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_drv.c b/drivers/gpu/drm/drm_drv.c index e572dd2..7d91ddb 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -231,7 +231,6 @@ 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); diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c index 3f84277..41a57c8 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); + + /* set address_space for shared mappings */ + filp->f_mapping = dev->anon_inode->i_mapping; retcode = drm_open_helper(inode, filp, dev); if (retcode) @@ -122,12 +113,6 @@ 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; } @@ -492,9 +477,6 @@ 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 39d8645..0d9efa2 100644 --- a/drivers/gpu/drm/drm_stub.c +++ b/drivers/gpu/drm/drm_stub.c @@ -31,6 +31,7 @@ * DEALINGS IN THE SOFTWARE. */ +#include <linux/anon_inodes.h> #include <linux/module.h> #include <linux/moduleparam.h> #include <linux/slab.h> @@ -271,8 +272,14 @@ int drm_fill_in_dev(struct drm_device *dev, mutex_init(&dev->struct_mutex); mutex_init(&dev->ctxlist_mutex); + /* create private address_space on anon inode */ + dev->anon_inode = anon_inode_new(); + if (IS_ERR(dev->anon_inode)) + return PTR_ERR(dev->anon_inode); + if (drm_ht_create(&dev->map_hash, 12)) { - return -ENOMEM; + retcode = -ENOMEM; + goto err_inode; } /* the DRM has 6 basic counters */ @@ -313,6 +320,8 @@ int drm_fill_in_dev(struct drm_device *dev, error_out_unreg: drm_lastclose(dev); +err_inode: + iput(dev->anon_inode); return retcode; } EXPORT_SYMBOL(drm_fill_in_dev); @@ -465,6 +474,7 @@ void drm_put_dev(struct drm_device *dev) drm_put_minor(&dev->primary); + iput(dev->anon_inode); list_del(&dev->driver_item); kfree(dev->devname); kfree(dev); diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 36c4ad9..fc571cc 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1435,7 +1435,8 @@ 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 07b192f..bb2a1cb 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 f32b712..4572758 100644 --- a/drivers/gpu/drm/nouveau/nouveau_gem.c +++ b/drivers/gpu/drm/nouveau/nouveau_gem.c @@ -237,7 +237,7 @@ 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 533f6eb..7115c23 100644 --- a/drivers/gpu/drm/omapdrm/omap_gem.c +++ b/drivers/gpu/drm/omapdrm/omap_gem.c @@ -153,7 +153,7 @@ static struct { static void evict_entry(struct drm_gem_object *obj, enum tiler_fmt fmt, struct usergart_entry *entry) { - if (obj->dev->dev_mapping) { + if (obj->dev->anon_inode->i_mapping) { struct omap_gem_object *omap_obj = to_omap_bo(obj); int n = usergart[fmt].height; size_t size = PAGE_SIZE * n; @@ -164,12 +164,13 @@ static void evict_entry(struct drm_gem_object *obj, int i; /* if stride > than PAGE_SIZE then sparse mapping: */ for (i = n; i > 0; i--) { - unmap_mapping_range(obj->dev->dev_mapping, + unmap_mapping_range(obj->dev->anon_inode->i_mapping, off, PAGE_SIZE, 1); off += PAGE_SIZE * m; } } else { - unmap_mapping_range(obj->dev->dev_mapping, off, size, 1); + unmap_mapping_range(obj->dev->anon_inode->i_mapping, + off, size, 1); } } diff --git a/drivers/gpu/drm/qxl/qxl_object.c b/drivers/gpu/drm/qxl/qxl_object.c index 8691c76..f3204c9 100644 --- a/drivers/gpu/drm/qxl/qxl_object.c +++ b/drivers/gpu/drm/qxl/qxl_object.c @@ -83,7 +83,7 @@ int qxl_bo_create(struct qxl_device *qdev, 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 037786d..7d7ff7a 100644 --- a/drivers/gpu/drm/qxl/qxl_ttm.c +++ b/drivers/gpu/drm/qxl/qxl_ttm.c @@ -517,7 +517,7 @@ int qxl_ttm_init(struct qxl_device *qdev) DRM_INFO("qxl: %luM of IO pages memory ready (VRAM domain)\n", ((unsigned)num_io_pages * PAGE_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 c0fa4aa..0900b36 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 71245d6..ab1b8ff 100644 --- a/drivers/gpu/drm/radeon/radeon_ttm.c +++ b/drivers/gpu/drm/radeon/radeon_ttm.c @@ -737,7 +737,7 @@ 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 1a90f0a..d5a20c4 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c @@ -762,7 +762,7 @@ 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 b46fb45..073772a 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1197,7 +1197,7 @@ struct drm_device { unsigned int num_crtcs; /**< Number of CRTCs on this device */ void *dev_private; /**< device private data */ void *mm_private; - struct address_space *dev_mapping; + struct inode *anon_inode; struct drm_sigdata sigdata; /**< For block_all_signals */ sigset_t sigmask; -- 1.8.4 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel