On Fri, Oct 09, 2020 at 06:16:06PM +0200, Daniel Vetter wrote:

On Fri, Oct 9, 2020 at 12:21 PM Chris Wilson chris@chris-wilson.co.uk wrote:

...

vgem is a minimalistic driver that provides shmemfs objects to userspace that may then be used as an in-memory surface and transported across dma-buf to other drivers. Since it's introduction, drm_gem_shmem_helper now provides the same shmemfs facilities and so we can trim vgem to wrap the helper.

Signed-off-by: Chris Wilson chris@chris-wilson.co.uk

drivers/gpu/drm/Kconfig | 1 + drivers/gpu/drm/vgem/vgem_drv.c | 281 ++------------------------------ drivers/gpu/drm/vgem/vgem_drv.h | 11 -- 3 files changed, 13 insertions(+), 280 deletions(-)

Nice diffstat :-)

Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch

Just noticed, but I think with

.dumb_create = drm_gem_shmem_dumb_create,

you can delete a bunhc more :-) -Daniel

...

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index 147d61b9674e..db2ff76638cd 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -278,6 +278,7 @@ source "drivers/gpu/drm/i915/Kconfig" config DRM_VGEM tristate "Virtual GEM provider" depends on DRM

•   select DRM_GEM_SHMEM_HELPER
    help
      Choose this option to get a virtual graphics memory manager,
      as used by Mesa's software renderer for enhanced performance.
  

diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index fa54a6d1403d..73cb17c4f7a8 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -38,6 +38,7 @@

#include <drm/drm_drv.h> #include <drm/drm_file.h> +#include <drm/drm_gem_shmem_helper.h> #include <drm/drm_ioctl.h> #include <drm/drm_managed.h> #include <drm/drm_prime.h> @@ -50,87 +51,11 @@ #define DRIVER_MAJOR 1 #define DRIVER_MINOR 0

-static const struct drm_gem_object_funcs vgem_gem_object_funcs;

static struct vgem_device { struct drm_device drm; struct platform_device *platform; } *vgem_device;

-static void vgem_gem_free_object(struct drm_gem_object *obj) -{

•   struct drm_vgem_gem_object *vgem_obj = to_vgem_bo(obj);
  

•   kvfree(vgem_obj->pages);
  

•   mutex_destroy(&vgem_obj->pages_lock);
  

•   if (obj->import_attach)
  

•           drm_prime_gem_destroy(obj, vgem_obj->table);
  

•   drm_gem_object_release(obj);
  

•   kfree(vgem_obj);
  

-}

-static vm_fault_t vgem_gem_fault(struct vm_fault *vmf) -{

•   struct vm_area_struct *vma = vmf->vma;
  

•   struct drm_vgem_gem_object *obj = vma->vm_private_data;
  

•   /* We don't use vmf->pgoff since that has the fake offset */
  

•   unsigned long vaddr = vmf->address;
  

•   vm_fault_t ret = VM_FAULT_SIGBUS;
  

•   loff_t num_pages;
  

•   pgoff_t page_offset;
  

•   page_offset = (vaddr - vma->vm_start) >> PAGE_SHIFT;
  

•   num_pages = DIV_ROUND_UP(obj->base.size, PAGE_SIZE);
  

•   if (page_offset >= num_pages)
  

•           return VM_FAULT_SIGBUS;
  

•   mutex_lock(&obj->pages_lock);
  

•   if (obj->pages) {
  

•           get_page(obj->pages[page_offset]);
  

•           vmf->page = obj->pages[page_offset];
  

•           ret = 0;
  

•   }
  

•   mutex_unlock(&obj->pages_lock);
  

•   if (ret) {
  

•           struct page *page;
  

•           page = shmem_read_mapping_page(
  

•                                   file_inode(obj->base.filp)->i_mapping,
  

•                                   page_offset);
  

•           if (!IS_ERR(page)) {
  

•                   vmf->page = page;
  

•                   ret = 0;
  

•           } else switch (PTR_ERR(page)) {
  

•                   case -ENOSPC:
  

•                   case -ENOMEM:
  

•                           ret = VM_FAULT_OOM;
  

•                           break;
  

•                   case -EBUSY:
  

•                           ret = VM_FAULT_RETRY;
  

•                           break;
  

•                   case -EFAULT:
  

•                   case -EINVAL:
  

•                           ret = VM_FAULT_SIGBUS;
  

•                           break;
  

•                   default:
  

•                           WARN_ON(PTR_ERR(page));
  

•                           ret = VM_FAULT_SIGBUS;
  

•                           break;
  

•           }
  

•   }
  

•   return ret;
  

-}

-static const struct vm_operations_struct vgem_gem_vm_ops = {

•   .fault = vgem_gem_fault,
  

•   .open = drm_gem_vm_open,
  

•   .close = drm_gem_vm_close,
  

-};

static int vgem_open(struct drm_device *dev, struct drm_file *file) { struct vgem_file *vfile; @@ -159,41 +84,25 @@ static void vgem_postclose(struct drm_device *dev, struct drm_file *file) kfree(vfile); }

-static struct drm_vgem_gem_object *__vgem_gem_create(struct drm_device *dev, +static struct drm_gem_shmem_object *__vgem_gem_create(struct drm_device *dev, unsigned long size) {

•   struct drm_vgem_gem_object *obj;
  

•   int ret;
  

•   obj = kzalloc(sizeof(*obj), GFP_KERNEL);
  

•   if (!obj)
  

•           return ERR_PTR(-ENOMEM);
  

•   struct drm_gem_shmem_object *obj;
  
  

•   obj->base.funcs = &vgem_gem_object_funcs;
  

•   ret = drm_gem_object_init(dev, &obj->base, roundup(size, PAGE_SIZE));
  

•   if (ret) {
  

•           kfree(obj);
  

•           return ERR_PTR(ret);
  

•   }
  

•   mutex_init(&obj->pages_lock);
  

•   obj = drm_gem_shmem_create(dev, round_up(size, PAGE_SIZE));
  

•   if (IS_ERR(obj))
  

•           return obj;
  
  

•   obj->map_cached = true;
    return obj;
  

}

-static void __vgem_gem_destroy(struct drm_vgem_gem_object *obj) -{

•   drm_gem_object_release(&obj->base);
  

•   kfree(obj);
  

-}

static struct drm_gem_object *vgem_gem_create(struct drm_device *dev, struct drm_file *file, unsigned int *handle, unsigned long size) {

•   struct drm_vgem_gem_object *obj;
  

•   struct drm_gem_shmem_object *obj;
    int ret;
  
    obj = __vgem_gem_create(dev, size);
  

@@ -239,96 +148,9 @@ static struct drm_ioctl_desc vgem_ioctls[] = { DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_RENDER_ALLOW), };

-static int vgem_mmap(struct file *filp, struct vm_area_struct *vma) -{

•   unsigned long flags = vma->vm_flags;
  

•   int ret;
  

•   ret = drm_gem_mmap(filp, vma);
  

•   if (ret)
  

•           return ret;
  

•   /* Keep the WC mmaping set by drm_gem_mmap() but our pages
  

•    * are ordinary and not special.
  

•    */
  

•   vma->vm_flags = flags | VM_DONTEXPAND | VM_DONTDUMP;
  

•   return 0;
  

-}

-static const struct file_operations vgem_driver_fops = {

•   .owner          = THIS_MODULE,
  

•   .open           = drm_open,
  

•   .mmap           = vgem_mmap,
  

•   .poll           = drm_poll,
  

•   .read           = drm_read,
  

•   .unlocked_ioctl = drm_ioctl,
  

•   .compat_ioctl   = drm_compat_ioctl,
  

•   .release        = drm_release,
  

-};

-static struct page **vgem_pin_pages(struct drm_vgem_gem_object *bo) -{

•   mutex_lock(&bo->pages_lock);
  

•   if (bo->pages_pin_count++ == 0) {
  

•           struct page **pages;
  

•           pages = drm_gem_get_pages(&bo->base);
  

•           if (IS_ERR(pages)) {
  

•                   bo->pages_pin_count--;
  

•                   mutex_unlock(&bo->pages_lock);
  

•                   return pages;
  

•           }
  

•           bo->pages = pages;
  

•   }
  

•   mutex_unlock(&bo->pages_lock);
  

•   return bo->pages;
  

-}

-static void vgem_unpin_pages(struct drm_vgem_gem_object *bo) -{

•   mutex_lock(&bo->pages_lock);
  

•   if (--bo->pages_pin_count == 0) {
  

•           drm_gem_put_pages(&bo->base, bo->pages, true, true);
  

•           bo->pages = NULL;
  

•   }
  

•   mutex_unlock(&bo->pages_lock);
  

-}

-static int vgem_prime_pin(struct drm_gem_object *obj) -{

•   struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
  

•   long n_pages = obj->size >> PAGE_SHIFT;
  

•   struct page **pages;
  

+DEFINE_DRM_GEM_FOPS(vgem_driver_fops);

•   pages = vgem_pin_pages(bo);
  

•   if (IS_ERR(pages))
  

•           return PTR_ERR(pages);
  

•   /* Flush the object from the CPU cache so that importers can rely
  

•    * on coherent indirect access via the exported dma-address.
  

•    */
  

•   drm_clflush_pages(pages, n_pages);
  

•   return 0;
  

-}

-static void vgem_prime_unpin(struct drm_gem_object *obj) -{

•   struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
  

•   vgem_unpin_pages(bo);
  

-}

-static struct sg_table *vgem_prime_get_sg_table(struct drm_gem_object *obj) -{

•   struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
  

•   return drm_prime_pages_to_sg(obj->dev, bo->pages, bo->base.size >> PAGE_SHIFT);
  

-}

-static struct drm_gem_object* vgem_prime_import(struct drm_device *dev, +static struct drm_gem_object *vgem_prime_import(struct drm_device *dev, struct dma_buf *dma_buf) { struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm); @@ -336,85 +158,6 @@ static struct drm_gem_object* vgem_prime_import(struct drm_device *dev, return drm_gem_prime_import_dev(dev, dma_buf, &vgem->platform->dev); }

-static struct drm_gem_object *vgem_prime_import_sg_table(struct drm_device *dev,

•                   struct dma_buf_attachment *attach, struct sg_table *sg)
  

-{

•   struct drm_vgem_gem_object *obj;
  

•   int npages;
  

•   obj = __vgem_gem_create(dev, attach->dmabuf->size);
  

•   if (IS_ERR(obj))
  

•           return ERR_CAST(obj);
  

•   npages = PAGE_ALIGN(attach->dmabuf->size) / PAGE_SIZE;
  

•   obj->table = sg;
  

•   obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
  

•   if (!obj->pages) {
  

•           __vgem_gem_destroy(obj);
  

•           return ERR_PTR(-ENOMEM);
  

•   }
  

•   obj->pages_pin_count++; /* perma-pinned */
  

•   drm_prime_sg_to_page_addr_arrays(obj->table, obj->pages, NULL,
  

•                                   npages);
  

•   return &obj->base;
  

-}

-static void *vgem_prime_vmap(struct drm_gem_object *obj) -{

•   struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
  

•   long n_pages = obj->size >> PAGE_SHIFT;
  

•   struct page **pages;
  

•   pages = vgem_pin_pages(bo);
  

•   if (IS_ERR(pages))
  

•           return NULL;
  

•   return vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL));
  

-}

-static void vgem_prime_vunmap(struct drm_gem_object *obj, void *vaddr) -{

•   struct drm_vgem_gem_object *bo = to_vgem_bo(obj);
  

•   vunmap(vaddr);
  

•   vgem_unpin_pages(bo);
  

-}

-static int vgem_prime_mmap(struct drm_gem_object *obj,

•                      struct vm_area_struct *vma)
  

-{

•   int ret;
  

•   if (obj->size < vma->vm_end - vma->vm_start)
  

•           return -EINVAL;
  

•   if (!obj->filp)
  

•           return -ENODEV;
  

•   ret = call_mmap(obj->filp, vma);
  

•   if (ret)
  

•           return ret;
  

•   fput(vma->vm_file);
  

•   vma->vm_file = get_file(obj->filp);
  

•   vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
  

•   vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
  

•   return 0;
  

-}

-static const struct drm_gem_object_funcs vgem_gem_object_funcs = {

•   .free = vgem_gem_free_object,
  

•   .pin = vgem_prime_pin,
  

•   .unpin = vgem_prime_unpin,
  

•   .get_sg_table = vgem_prime_get_sg_table,
  

•   .vmap = vgem_prime_vmap,
  

•   .vunmap = vgem_prime_vunmap,
  

•   .vm_ops = &vgem_gem_vm_ops,
  

-};

static struct drm_driver vgem_driver = { .driver_features = DRIVER_GEM | DRIVER_RENDER, .open = vgem_open, @@ -428,8 +171,8 @@ static struct drm_driver vgem_driver = { .prime_handle_to_fd = drm_gem_prime_handle_to_fd, .prime_fd_to_handle = drm_gem_prime_fd_to_handle, .gem_prime_import = vgem_prime_import,

•   .gem_prime_import_sg_table = vgem_prime_import_sg_table,
  

•   .gem_prime_mmap = vgem_prime_mmap,
  

•   .gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table,
  

•   .gem_prime_mmap = drm_gem_prime_mmap,
  
    .name   = DRIVER_NAME,
    .desc   = DRIVER_DESC,
  

diff --git a/drivers/gpu/drm/vgem/vgem_drv.h b/drivers/gpu/drm/vgem/vgem_drv.h index 0ed300317f87..34cf63e6fb3d 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.h +++ b/drivers/gpu/drm/vgem/vgem_drv.h @@ -39,17 +39,6 @@ struct vgem_file { struct mutex fence_mutex; };

-#define to_vgem_bo(x) container_of(x, struct drm_vgem_gem_object, base) -struct drm_vgem_gem_object {

•   struct drm_gem_object base;
  

•   struct page **pages;
  

•   unsigned int pages_pin_count;
  

•   struct mutex pages_lock;
  

•   struct sg_table *table;
  

-};

int vgem_fence_open(struct vgem_file *file); int vgem_fence_attach_ioctl(struct drm_device *dev, void *data, -- 2.20.1

---

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-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch