drm/amdgpu: Implement mmap as GEM object function
authorThomas Zimmermann <tzimmermann@suse.de>
Tue, 25 May 2021 15:10:50 +0000 (17:10 +0200)
committerThomas Zimmermann <tzimmermann@suse.de>
Wed, 26 May 2021 18:56:23 +0000 (20:56 +0200)
Moving the driver-specific mmap code into a GEM object function allows
for using DRM helpers for various mmap callbacks.

This change resolves several inconsistencies between regular mmap and
prime-based mmap. The vm_ops field in vma is now set for all mmap'ed
areas. Previously it way only set for regular mmap calls, prime-based
mmap used TTM's default vm_ops. The function amdgpu_verify_access() is
no longer being called and therefore removed by this patch.

As a side effect, amdgpu_ttm_vm_ops and amdgpu_ttm_fault() are now
implemented in amdgpu's GEM code.

v4:
* rebased
v3:
* rename mmap function to amdgpu_gem_object_mmap() (Christian)
* remove unnecessary checks from mmap (Christian)
v2:
* rename amdgpu_ttm_vm_ops and amdgpu_ttm_fault() to
  amdgpu_gem_vm_ops and amdgpu_gem_fault() (Christian)
* the check for kfd_bo has meanwhile been removed

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210525151055.8174-3-tzimmermann@suse.de
drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h

index baa980a..6ec1312 100644 (file)
 #include <linux/pci-p2pdma.h>
 #include <linux/pm_runtime.h>
 
-/**
- * amdgpu_gem_prime_mmap - &drm_driver.gem_prime_mmap implementation
- * @obj: GEM BO
- * @vma: Virtual memory area
- *
- * Sets up a userspace mapping of the BO's memory in the given
- * virtual memory area.
- *
- * Returns:
- * 0 on success or a negative error code on failure.
- */
-int amdgpu_gem_prime_mmap(struct drm_gem_object *obj,
-                         struct vm_area_struct *vma)
-{
-       struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
-       struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
-       unsigned asize = amdgpu_bo_size(bo);
-       int ret;
-
-       if (!vma->vm_file)
-               return -ENODEV;
-
-       if (adev == NULL)
-               return -ENODEV;
-
-       /* Check for valid size. */
-       if (asize < vma->vm_end - vma->vm_start)
-               return -EINVAL;
-
-       if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm) ||
-           (bo->flags & AMDGPU_GEM_CREATE_NO_CPU_ACCESS)) {
-               return -EPERM;
-       }
-       vma->vm_pgoff += amdgpu_bo_mmap_offset(bo) >> PAGE_SHIFT;
-
-       /* prime mmap does not need to check access, so allow here */
-       ret = drm_vma_node_allow(&obj->vma_node, vma->vm_file->private_data);
-       if (ret)
-               return ret;
-
-       ret = ttm_bo_mmap(vma->vm_file, vma, &adev->mman.bdev);
-       drm_vma_node_revoke(&obj->vma_node, vma->vm_file->private_data);
-
-       return ret;
-}
-
 static int
 __dma_resv_make_exclusive(struct dma_resv *obj)
 {
index 39b5b96..3e93b9b 100644 (file)
@@ -31,8 +31,6 @@ struct drm_gem_object *amdgpu_gem_prime_import(struct drm_device *dev,
                                            struct dma_buf *dma_buf);
 bool amdgpu_dmabuf_is_xgmi_accessible(struct amdgpu_device *adev,
                                      struct amdgpu_bo *bo);
-int amdgpu_gem_prime_mmap(struct drm_gem_object *obj,
-                         struct vm_area_struct *vma);
 
 extern const struct dma_buf_ops amdgpu_dmabuf_ops;
 
index e8bbcde..0d7017a 100644 (file)
@@ -1695,7 +1695,7 @@ static const struct file_operations amdgpu_driver_kms_fops = {
        .flush = amdgpu_flush,
        .release = drm_release,
        .unlocked_ioctl = amdgpu_drm_ioctl,
-       .mmap = amdgpu_mmap,
+       .mmap = drm_gem_mmap,
        .poll = drm_poll,
        .read = drm_read,
 #ifdef CONFIG_COMPAT
@@ -1762,7 +1762,7 @@ static const struct drm_driver amdgpu_kms_driver = {
        .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
        .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
        .gem_prime_import = amdgpu_gem_prime_import,
-       .gem_prime_mmap = amdgpu_gem_prime_mmap,
+       .gem_prime_mmap = drm_gem_prime_mmap,
 
        .name = DRIVER_NAME,
        .desc = DRIVER_DESC,
index 18974bd..73c76a3 100644 (file)
@@ -32,6 +32,7 @@
 #include <linux/dma-buf.h>
 
 #include <drm/amdgpu_drm.h>
+#include <drm/drm_drv.h>
 #include <drm/drm_gem_ttm_helper.h>
 
 #include "amdgpu.h"
 
 static const struct drm_gem_object_funcs amdgpu_gem_object_funcs;
 
+static vm_fault_t amdgpu_gem_fault(struct vm_fault *vmf)
+{
+       struct ttm_buffer_object *bo = vmf->vma->vm_private_data;
+       struct drm_device *ddev = bo->base.dev;
+       vm_fault_t ret;
+       int idx;
+
+       ret = ttm_bo_vm_reserve(bo, vmf);
+       if (ret)
+               return ret;
+
+       if (drm_dev_enter(ddev, &idx)) {
+               ret = amdgpu_bo_fault_reserve_notify(bo);
+               if (ret) {
+                       drm_dev_exit(idx);
+                       goto unlock;
+               }
+
+                ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot,
+                                               TTM_BO_VM_NUM_PREFAULT, 1);
+
+                drm_dev_exit(idx);
+       } else {
+               ret = ttm_bo_vm_dummy_page(vmf, vmf->vma->vm_page_prot);
+       }
+       if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
+               return ret;
+
+unlock:
+       dma_resv_unlock(bo->base.resv);
+       return ret;
+}
+
+static const struct vm_operations_struct amdgpu_gem_vm_ops = {
+       .fault = amdgpu_gem_fault,
+       .open = ttm_bo_vm_open,
+       .close = ttm_bo_vm_close,
+       .access = ttm_bo_vm_access
+};
+
 static void amdgpu_gem_object_free(struct drm_gem_object *gobj)
 {
        struct amdgpu_bo *robj = gem_to_amdgpu_bo(gobj);
@@ -205,6 +246,18 @@ out_unlock:
        ttm_eu_backoff_reservation(&ticket, &list);
 }
 
+static int amdgpu_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
+{
+       struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
+
+       if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm))
+               return -EPERM;
+       if (bo->flags & AMDGPU_GEM_CREATE_NO_CPU_ACCESS)
+               return -EPERM;
+
+       return drm_gem_ttm_mmap(obj, vma);
+}
+
 static const struct drm_gem_object_funcs amdgpu_gem_object_funcs = {
        .free = amdgpu_gem_object_free,
        .open = amdgpu_gem_object_open,
@@ -212,6 +265,8 @@ static const struct drm_gem_object_funcs amdgpu_gem_object_funcs = {
        .export = amdgpu_gem_prime_export,
        .vmap = drm_gem_ttm_vmap,
        .vunmap = drm_gem_ttm_vunmap,
+       .mmap = amdgpu_gem_object_mmap,
+       .vm_ops = &amdgpu_gem_vm_ops,
 };
 
 /*
index 3bc3aeb..80437b6 100644 (file)
@@ -47,7 +47,6 @@
 #include <drm/ttm/ttm_placement.h>
 
 #include <drm/amdgpu_drm.h>
-#include <drm/drm_drv.h>
 
 #include "amdgpu.h"
 #include "amdgpu_object.h"
@@ -167,25 +166,6 @@ static void amdgpu_evict_flags(struct ttm_buffer_object *bo,
 }
 
 /**
- * amdgpu_verify_access - Verify access for a mmap call
- *
- * @bo:        The buffer object to map
- * @filp: The file pointer from the process performing the mmap
- *
- * This is called by ttm_bo_mmap() to verify whether a process
- * has the right to mmap a BO to their process space.
- */
-static int amdgpu_verify_access(struct ttm_buffer_object *bo, struct file *filp)
-{
-       struct amdgpu_bo *abo = ttm_to_amdgpu_bo(bo);
-
-       if (amdgpu_ttm_tt_get_usermm(bo->ttm))
-               return -EPERM;
-       return drm_vma_node_verify_access(&abo->tbo.base.vma_node,
-                                         filp->private_data);
-}
-
-/**
  * amdgpu_ttm_map_buffer - Map memory into the GART windows
  * @bo: buffer object to map
  * @mem: memory object to map
@@ -1476,7 +1456,6 @@ static struct ttm_device_funcs amdgpu_bo_driver = {
        .eviction_valuable = amdgpu_ttm_bo_eviction_valuable,
        .evict_flags = &amdgpu_evict_flags,
        .move = &amdgpu_bo_move,
-       .verify_access = &amdgpu_verify_access,
        .delete_mem_notify = &amdgpu_bo_delete_mem_notify,
        .release_notify = &amdgpu_bo_release_notify,
        .io_mem_reserve = &amdgpu_ttm_io_mem_reserve,
@@ -1844,60 +1823,6 @@ void amdgpu_ttm_set_buffer_funcs_status(struct amdgpu_device *adev, bool enable)
        adev->mman.buffer_funcs_enabled = enable;
 }
 
-static vm_fault_t amdgpu_ttm_fault(struct vm_fault *vmf)
-{
-       struct ttm_buffer_object *bo = vmf->vma->vm_private_data;
-       struct drm_device *ddev = bo->base.dev;
-       vm_fault_t ret;
-       int idx;
-
-       ret = ttm_bo_vm_reserve(bo, vmf);
-       if (ret)
-               return ret;
-
-       if (drm_dev_enter(ddev, &idx)) {
-               ret = amdgpu_bo_fault_reserve_notify(bo);
-               if (ret) {
-                       drm_dev_exit(idx);
-                       goto unlock;
-               }
-
-                ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot,
-                                               TTM_BO_VM_NUM_PREFAULT, 1);
-
-                drm_dev_exit(idx);
-       } else {
-               ret = ttm_bo_vm_dummy_page(vmf, vmf->vma->vm_page_prot);
-       }
-       if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
-               return ret;
-
-unlock:
-       dma_resv_unlock(bo->base.resv);
-       return ret;
-}
-
-static const struct vm_operations_struct amdgpu_ttm_vm_ops = {
-       .fault = amdgpu_ttm_fault,
-       .open = ttm_bo_vm_open,
-       .close = ttm_bo_vm_close,
-       .access = ttm_bo_vm_access
-};
-
-int amdgpu_mmap(struct file *filp, struct vm_area_struct *vma)
-{
-       struct drm_file *file_priv = filp->private_data;
-       struct amdgpu_device *adev = drm_to_adev(file_priv->minor->dev);
-       int r;
-
-       r = ttm_bo_mmap(filp, vma, &adev->mman.bdev);
-       if (unlikely(r != 0))
-               return r;
-
-       vma->vm_ops = &amdgpu_ttm_vm_ops;
-       return 0;
-}
-
 int amdgpu_copy_buffer(struct amdgpu_ring *ring, uint64_t src_offset,
                       uint64_t dst_offset, uint32_t byte_count,
                       struct dma_resv *resv,
index eb84a69..b2c97b1 100644 (file)
@@ -142,7 +142,6 @@ int amdgpu_fill_buffer(struct amdgpu_bo *bo,
                        struct dma_resv *resv,
                        struct dma_fence **fence);
 
-int amdgpu_mmap(struct file *filp, struct vm_area_struct *vma);
 int amdgpu_ttm_alloc_gart(struct ttm_buffer_object *bo);
 int amdgpu_ttm_recover_gart(struct ttm_buffer_object *tbo);
 uint64_t amdgpu_ttm_domain_start(struct amdgpu_device *adev, uint32_t type);