drm/amdgpu: move get_user_pages out of amdgpu_ttm_tt_pin_userptr v6
That avoids lock inversion between the BO reservation lock
and the anon_vma lock.
v2:
* Changed amdgpu_bo_list_entry.user_pages to an array of pointers
* Lock mmap_sem only for get_user_pages
* Added invalidation of unbound userpointer BOs
* Fixed memory leak and page reference leak
v3 (chk):
* Revert locking mmap_sem only for_get user_pages
* Revert adding invalidation of unbound userpointer BOs
* Sanitize and fix error handling
v4 (chk):
* Init userpages pointer everywhere.
* Fix error handling when get_user_pages() fails.
* Add invalidation of unbound userpointer BOs again.
v5 (chk):
* Add maximum number of tries.
v6 (chk):
* Fix error handling when we run out of tries.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com> (v4)
Acked-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 7833dfb..4f5ef41 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -111,6 +111,7 @@
p->uf_entry.priority = 0;
p->uf_entry.tv.bo = &p->uf_entry.robj->tbo;
p->uf_entry.tv.shared = true;
+ p->uf_entry.user_pages = NULL;
drm_gem_object_unreference_unlocked(gobj);
return 0;
@@ -297,6 +298,7 @@
list_for_each_entry(lobj, validated, tv.head) {
struct amdgpu_bo *bo = lobj->robj;
+ bool binding_userptr = false;
struct mm_struct *usermm;
uint32_t domain;
@@ -304,6 +306,15 @@
if (usermm && usermm != current->mm)
return -EPERM;
+ /* Check if we have user pages and nobody bound the BO already */
+ if (lobj->user_pages && bo->tbo.ttm->state != tt_bound) {
+ size_t size = sizeof(struct page *);
+
+ size *= bo->tbo.ttm->num_pages;
+ memcpy(bo->tbo.ttm->pages, lobj->user_pages, size);
+ binding_userptr = true;
+ }
+
if (bo->pin_count)
continue;
@@ -334,6 +345,11 @@
}
return r;
}
+
+ if (binding_userptr) {
+ drm_free_large(lobj->user_pages);
+ lobj->user_pages = NULL;
+ }
}
return 0;
}
@@ -342,8 +358,10 @@
union drm_amdgpu_cs *cs)
{
struct amdgpu_fpriv *fpriv = p->filp->driver_priv;
+ struct amdgpu_bo_list_entry *e;
struct list_head duplicates;
bool need_mmap_lock = false;
+ unsigned i, tries = 10;
int r;
INIT_LIST_HEAD(&p->validated);
@@ -364,9 +382,81 @@
if (need_mmap_lock)
down_read(¤t->mm->mmap_sem);
- r = ttm_eu_reserve_buffers(&p->ticket, &p->validated, true, &duplicates);
- if (unlikely(r != 0))
- goto error_reserve;
+ while (1) {
+ struct list_head need_pages;
+ unsigned i;
+
+ r = ttm_eu_reserve_buffers(&p->ticket, &p->validated, true,
+ &duplicates);
+ if (unlikely(r != 0))
+ goto error_free_pages;
+
+ /* Without a BO list we don't have userptr BOs */
+ if (!p->bo_list)
+ break;
+
+ INIT_LIST_HEAD(&need_pages);
+ for (i = p->bo_list->first_userptr;
+ i < p->bo_list->num_entries; ++i) {
+
+ e = &p->bo_list->array[i];
+
+ if (amdgpu_ttm_tt_userptr_invalidated(e->robj->tbo.ttm,
+ &e->user_invalidated) && e->user_pages) {
+
+ /* We acquired a page array, but somebody
+ * invalidated it. Free it an try again
+ */
+ release_pages(e->user_pages,
+ e->robj->tbo.ttm->num_pages,
+ false);
+ drm_free_large(e->user_pages);
+ e->user_pages = NULL;
+ }
+
+ if (e->robj->tbo.ttm->state != tt_bound &&
+ !e->user_pages) {
+ list_del(&e->tv.head);
+ list_add(&e->tv.head, &need_pages);
+
+ amdgpu_bo_unreserve(e->robj);
+ }
+ }
+
+ if (list_empty(&need_pages))
+ break;
+
+ /* Unreserve everything again. */
+ ttm_eu_backoff_reservation(&p->ticket, &p->validated);
+
+ /* We tried to often, just abort */
+ if (!--tries) {
+ r = -EDEADLK;
+ goto error_free_pages;
+ }
+
+ /* Fill the page arrays for all useptrs. */
+ list_for_each_entry(e, &need_pages, tv.head) {
+ struct ttm_tt *ttm = e->robj->tbo.ttm;
+
+ e->user_pages = drm_calloc_large(ttm->num_pages,
+ sizeof(struct page*));
+ if (!e->user_pages) {
+ r = -ENOMEM;
+ goto error_free_pages;
+ }
+
+ r = amdgpu_ttm_tt_get_user_pages(ttm, e->user_pages);
+ if (r) {
+ drm_free_large(e->user_pages);
+ e->user_pages = NULL;
+ goto error_free_pages;
+ }
+ }
+
+ /* And try again. */
+ list_splice(&need_pages, &p->validated);
+ }
amdgpu_vm_get_pt_bos(&fpriv->vm, &duplicates);
@@ -398,10 +488,26 @@
ttm_eu_backoff_reservation(&p->ticket, &p->validated);
}
-error_reserve:
+error_free_pages:
+
if (need_mmap_lock)
up_read(¤t->mm->mmap_sem);
+ if (p->bo_list) {
+ for (i = p->bo_list->first_userptr;
+ i < p->bo_list->num_entries; ++i) {
+ e = &p->bo_list->array[i];
+
+ if (!e->user_pages)
+ continue;
+
+ release_pages(e->user_pages,
+ e->robj->tbo.ttm->num_pages,
+ false);
+ drm_free_large(e->user_pages);
+ }
+ }
+
return r;
}