[RFC PATCH 12/13] drm/nouveau: HMM area creation helpers for nouveau client
jglisse at redhat.com
jglisse at redhat.com
Sat Mar 10 03:21:40 UTC 2018
From: Jérôme Glisse <jglisse at redhat.com>
Helpers to create area of virtual address under HMM control for a nouveau
client. GPU access to HMM area are valid as long as the hole vma exist in
the process virtual address space.
Signed-off-by: Jérôme Glisse <jglisse at redhat.com>
Cc: Ben Skeggs <bskeggs at redhat.com>
---
drivers/gpu/drm/nouveau/nouveau_hmm.c | 28 ++++++++++++
drivers/gpu/drm/nouveau/nouveau_hmm.h | 1 +
drivers/gpu/drm/nouveau/nouveau_vmm.c | 83 +++++++++++++++++++++++++++++++++++
drivers/gpu/drm/nouveau/nouveau_vmm.h | 12 +++++
4 files changed, 124 insertions(+)
diff --git a/drivers/gpu/drm/nouveau/nouveau_hmm.c b/drivers/gpu/drm/nouveau/nouveau_hmm.c
index a4c6f687f6a8..680e29bbf367 100644
--- a/drivers/gpu/drm/nouveau/nouveau_hmm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_hmm.c
@@ -245,6 +245,31 @@ nouveau_vmm_sync_pagetables(struct hmm_mirror *mirror,
unsigned long start,
unsigned long end)
{
+ struct nouveau_hmm *hmm;
+ struct nouveau_cli *cli;
+
+ hmm = container_of(mirror, struct nouveau_hmm, mirror);
+ if (!hmm->hole.vma || hmm->hole.start == hmm->hole.end)
+ return;
+
+ /* Ignore area inside hole */
+ end = min(end, TASK_SIZE);
+ if (start >= hmm->hole.start && end <= hmm->hole.end)
+ return;
+ if (start < hmm->hole.start && end > hmm->hole.start) {
+ nouveau_vmm_sync_pagetables(mirror, update, start,
+ hmm->hole.start);
+ start = hmm->hole.end;
+ } else if (start < hmm->hole.end && start >= hmm->hole.start) {
+ start = hmm->hole.end;
+ }
+ if (end <= start)
+ return;
+
+ cli = container_of(hmm, struct nouveau_cli, hmm);
+ mutex_lock(&hmm->mutex);
+ nvif_vmm_hmm_unmap(&cli->vmm.vmm, start, (end - start) >> PAGE_SHIFT);
+ mutex_unlock(&hmm->mutex);
}
static const struct hmm_mirror_ops nouveau_hmm_mirror_ops = {
@@ -254,6 +279,8 @@ static const struct hmm_mirror_ops nouveau_hmm_mirror_ops = {
void
nouveau_hmm_fini(struct nouveau_cli *cli)
{
+ struct nouveau_hmm *hmm = &cli->hmm;
+
if (!cli->hmm.enabled)
return;
@@ -262,6 +289,7 @@ nouveau_hmm_fini(struct nouveau_cli *cli)
nvif_object_fini(&cli->hmm.rpfb);
hmm_mirror_unregister(&cli->hmm.mirror);
+ nvif_vmm_hmm_fini(&cli->vmm.vmm, hmm->hole.start, hmm->hole.end);
nouveau_vmm_sync_pagetables(&cli->hmm.mirror, HMM_UPDATE_INVALIDATE,
PAGE_SIZE, TASK_SIZE);
}
diff --git a/drivers/gpu/drm/nouveau/nouveau_hmm.h b/drivers/gpu/drm/nouveau/nouveau_hmm.h
index 47f31cf8ac56..bc68dcf0748b 100644
--- a/drivers/gpu/drm/nouveau/nouveau_hmm.h
+++ b/drivers/gpu/drm/nouveau/nouveau_hmm.h
@@ -33,6 +33,7 @@
#if defined(CONFIG_HMM_MIRROR) && defined(CONFIG_DEVICE_PRIVATE)
struct nouveau_hmm {
+ struct nouveau_vmm_hole hole;
struct nvif_object rpfb;
struct nvif_notify pending;
struct task_struct *task;
diff --git a/drivers/gpu/drm/nouveau/nouveau_vmm.c b/drivers/gpu/drm/nouveau/nouveau_vmm.c
index f5371d96b003..8e6c47a99edb 100644
--- a/drivers/gpu/drm/nouveau/nouveau_vmm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_vmm.c
@@ -115,6 +115,89 @@ nouveau_vma_new(struct nouveau_bo *nvbo, struct nouveau_vmm *vmm,
return ret;
}
+static int
+vmm_hole_fault(struct vm_fault *vmf)
+{
+ return VM_FAULT_SIGBUS;
+}
+
+static void
+vmm_hole_open(struct vm_area_struct *vma)
+{
+ struct nouveau_cli *cli = vma->vm_private_data;
+ struct nouveau_vmm_hole *hole = &cli->hmm.hole;
+
+ /*
+ * No need for atomic this happen under mmap_sem write lock. Make sure
+ * this assumption holds with a BUG_ON()
+ */
+ BUG_ON(down_read_trylock(&vma->vm_mm->mmap_sem));
+ hole->count++;
+}
+
+static void
+vmm_hole_close(struct vm_area_struct *vma)
+{
+ struct nouveau_cli *cli = vma->vm_private_data;
+ struct nouveau_vmm_hole *hole = &cli->hmm.hole;
+
+ /*
+ * No need for atomic this happen under mmap_sem write lock with one
+ * exception when a process is being kill (from do_exit()). For that
+ * reasons we don't test with BUG_ON().
+ */
+ if ((--hole->count) <= 0) {
+ nouveau_hmm_fini(cli);
+ hole->vma = NULL;
+ }
+}
+
+static int
+vmm_hole_access(struct vm_area_struct *vma, unsigned long addr,
+ void *buf, int len, int write)
+{
+ return -EIO;
+}
+
+static const struct vm_operations_struct vmm_hole_vm_ops = {
+ .access = vmm_hole_access,
+ .close = vmm_hole_close,
+ .fault = vmm_hole_fault,
+ .open = vmm_hole_open,
+};
+
+int
+nouveau_vmm_hmm(struct nouveau_cli *cli, struct file *file,
+ struct vm_area_struct *vma)
+{
+ struct nouveau_vmm_hole *hole = &cli->hmm.hole;
+ unsigned long size = vma->vm_end - vma->vm_start;
+ unsigned long pgsize = size >> PAGE_SHIFT;
+ int ret;
+
+ if ((vma->vm_pgoff + pgsize) > (DRM_FILE_PAGE_OFFSET + (4UL << 30)))
+ return -EINVAL;
+
+ if (!cli->hmm.enabled)
+ return -EINVAL;
+
+ hole->vma = vma;
+ hole->cli = cli;
+ hole->file = file;
+ hole->start = vma->vm_start;
+ hole->end = vma->vm_end;
+ hole->count = 1;
+
+ ret = nvif_vmm_hmm_init(&cli->vmm.vmm, vma->vm_start, vma->vm_end);
+ if (ret)
+ return ret;
+
+ vma->vm_private_data = cli;
+ vma->vm_ops = &vmm_hole_vm_ops;
+ vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
+ return 0;
+}
+
void
nouveau_vmm_fini(struct nouveau_vmm *vmm)
{
diff --git a/drivers/gpu/drm/nouveau/nouveau_vmm.h b/drivers/gpu/drm/nouveau/nouveau_vmm.h
index 5c31f43678d3..43d30feb3057 100644
--- a/drivers/gpu/drm/nouveau/nouveau_vmm.h
+++ b/drivers/gpu/drm/nouveau/nouveau_vmm.h
@@ -13,6 +13,15 @@ struct nouveau_vma {
struct nouveau_mem *mem;
};
+struct nouveau_vmm_hole {
+ struct vm_area_struct *vma;
+ struct nouveau_cli *cli;
+ struct file *file;
+ unsigned long start;
+ unsigned long end;
+ int count;
+};
+
struct nouveau_vma *nouveau_vma_find(struct nouveau_bo *, struct nouveau_vmm *);
int nouveau_vma_new(struct nouveau_bo *, struct nouveau_vmm *,
struct nouveau_vma **);
@@ -26,6 +35,9 @@ struct nouveau_vmm {
struct nvkm_vm *vm;
};
+int nouveau_vmm_hmm(struct nouveau_cli *cli, struct file *file,
+ struct vm_area_struct *vma);
+
int nouveau_vmm_init(struct nouveau_cli *, s32 oclass, struct nouveau_vmm *);
void nouveau_vmm_fini(struct nouveau_vmm *);
#endif
--
2.14.3
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