[Intel-gfx] [PATCH 2/2] drm/vgem: Replace vgem_object_funcs with the common drm shmem helper
Chris Wilson
chris at chris-wilson.co.uk
Mon Oct 12 10:51:31 UTC 2020
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 vgem's introduction,
drm_gem_shmem_helper now provides the same shmemfs facilities and so we
can trim vgem to wrap the helper.
v2: The gem prime mmap helper does not handle exchanging the vma->file,
so skip the conversion to the common prime helper and leave the patch
only converting to the common shmem helper.
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch> #v1
---
drivers/gpu/drm/Kconfig | 1 +
drivers/gpu/drm/vgem/vgem_drv.c | 284 +++-----------------------------
drivers/gpu/drm/vgem/vgem_drv.h | 11 --
3 files changed, 25 insertions(+), 271 deletions(-)
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 f38dd590fa45..6811ac518509 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;
@@ -159,33 +84,15 @@ 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,
- unsigned long size)
+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);
-
- 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);
-
- return obj;
-}
-
-static void __vgem_gem_destroy(struct drm_vgem_gem_object *obj)
-{
- drm_gem_object_release(&obj->base);
- kfree(obj);
+ /*
+ * How should we use map_cached? prime vmaps should be write-combining
+ * so that device coherency can be assumed, but ordinary user mmaps
+ * would benefit from being write-back.
+ */
+ return drm_gem_shmem_create(dev, round_up(size, PAGE_SIZE));
}
static struct drm_gem_object *vgem_gem_create(struct drm_device *dev,
@@ -193,7 +100,7 @@ static struct drm_gem_object *vgem_gem_create(struct drm_device *dev,
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);
@@ -234,154 +141,6 @@ static int vgem_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
return 0;
}
-static struct drm_ioctl_desc vgem_ioctls[] = {
- DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_RENDER_ALLOW),
- 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, false);
- 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;
-
- 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,
- struct dma_buf *dma_buf)
-{
- struct vgem_device *vgem = container_of(dev, typeof(*vgem), drm);
-
- 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)
{
@@ -405,16 +164,21 @@ static int vgem_prime_mmap(struct drm_gem_object *obj,
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_ioctl_desc vgem_ioctls[] = {
+ DRM_IOCTL_DEF_DRV(VGEM_FENCE_ATTACH, vgem_fence_attach_ioctl, DRM_RENDER_ALLOW),
+ DRM_IOCTL_DEF_DRV(VGEM_FENCE_SIGNAL, vgem_fence_signal_ioctl, DRM_RENDER_ALLOW),
};
+DEFINE_DRM_GEM_FOPS(vgem_driver_fops);
+
+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);
+
+ return drm_gem_prime_import_dev(dev, dma_buf, &vgem->platform->dev);
+}
+
static struct drm_driver vgem_driver = {
.driver_features = DRIVER_GEM | DRIVER_RENDER,
.open = vgem_open,
@@ -428,7 +192,7 @@ 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_import_sg_table = drm_gem_shmem_prime_import_sg_table,
.gem_prime_mmap = vgem_prime_mmap,
.name = DRIVER_NAME,
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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