nouveau: move more abi16-specific logic into abi16.c

v2.
- add a comment about the (ab)use of nouveau_object::length
- add a comment about abi16_object() return values
v3.
- handle new client + old kernel for sw classes

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Tested-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>

3 files changed, 93 insertions, 58 deletions

diff --git a/nouveau/abi16.c b/nouveau/abi16.c
index 59bc4360..44fda645 100644
--- a/nouveau/abi16.c
+++ b/nouveau/abi16.c
@@ -32,8 +32,10 @@
 
 #include "private.h"
 
+#include "nvif/class.h"
 
-drm_private int
+
+static int
 abi16_chan_nv04(struct nouveau_object *obj)
 {
         struct nouveau_device *dev = (struct nouveau_device *)obj->parent;
@@ -57,7 +59,7 @@ abi16_chan_nv04(struct nouveau_object *obj)
         return 0;
 }
 
-drm_private int
+static int
 abi16_chan_nvc0(struct nouveau_object *obj)
 {
         struct nouveau_device *dev = (struct nouveau_device *)obj->parent;
@@ -78,7 +80,7 @@ abi16_chan_nvc0(struct nouveau_object *obj)
         return 0;
 }
 
-drm_private int
+static int
 abi16_chan_nve0(struct nouveau_object *obj)
 {
         struct nouveau_device *dev = (struct nouveau_device *)obj->parent;
@@ -104,7 +106,7 @@ abi16_chan_nve0(struct nouveau_object *obj)
         return 0;
 }
 
-drm_private int
+static int
 abi16_engobj(struct nouveau_object *obj)
 {
         struct drm_nouveau_grobj_alloc req = {
@@ -115,6 +117,27 @@ abi16_engobj(struct nouveau_object *obj)
         struct nouveau_device *dev;
         int ret;
 
+        /* Older kernel versions did not have the concept of nouveau-
+         * specific classes and abused some NVIDIA-assigned ones for
+         * a SW class.  The ABI16 layer has compatibility in place to
+         * translate these older identifiers to the newer ones.
+         *
+         * Clients that have been updated to use NVIF are required to
+         * use the newer class identifiers, which means that they'll
+         * break if running on an older kernel.
+         *
+         * To handle this case, when using ABI16, we translate to the
+         * older values which work on any kernel.
+         */
+        switch (req.class) {
+        case NVIF_CLASS_SW_NV04 : req.class = 0x006e; break;
+        case NVIF_CLASS_SW_NV10 : req.class = 0x016e; break;
+        case NVIF_CLASS_SW_NV50 : req.class = 0x506e; break;
+        case NVIF_CLASS_SW_GF100: req.class = 0x906e; break;
+        default:
+                break;
+        }
+
         dev = nouveau_object_find(obj, NOUVEAU_DEVICE_CLASS);
         ret = drmCommandWrite(dev->fd, DRM_NOUVEAU_GROBJ_ALLOC,
                               &req, sizeof(req));
@@ -125,7 +148,7 @@ abi16_engobj(struct nouveau_object *obj)
         return 0;
 }
 
-drm_private int
+static int
 abi16_ntfy(struct nouveau_object *obj)
 {
         struct nv04_notify *ntfy = obj->data;
@@ -149,6 +172,61 @@ abi16_ntfy(struct nouveau_object *obj)
 }
 
 drm_private void
+abi16_delete(struct nouveau_object *obj)
+{
+        struct nouveau_device *dev =
+                nouveau_object_find(obj, NOUVEAU_DEVICE_CLASS);
+        if (obj->oclass == NOUVEAU_FIFO_CHANNEL_CLASS) {
+                struct drm_nouveau_channel_free req;
+                req.channel = obj->handle;
+                drmCommandWrite(dev->fd, DRM_NOUVEAU_CHANNEL_FREE,
+                                &req, sizeof(req));
+        } else {
+                struct drm_nouveau_gpuobj_free req;
+                req.channel = obj->parent->handle;
+                req.handle  = obj->handle;
+                drmCommandWrite(dev->fd, DRM_NOUVEAU_GPUOBJ_FREE,
+                                &req, sizeof(req));
+        }
+}
+
+drm_private bool
+abi16_object(struct nouveau_object *obj, int (**func)(struct nouveau_object *))
+{
+        struct nouveau_object *parent = obj->parent;
+
+        /* nouveau_object::length is (ab)used to determine whether the
+         * object is a legacy object (!=0), or a real NVIF object.
+         */
+        if ((parent->length != 0 && parent->oclass == NOUVEAU_DEVICE_CLASS)) {
+                if (obj->oclass == NOUVEAU_FIFO_CHANNEL_CLASS) {
+                        struct nouveau_device *dev = (void *)parent;
+                        if (dev->chipset < 0xc0)
+                                *func = abi16_chan_nv04;
+                        else
+                        if (dev->chipset < 0xe0)
+                                *func = abi16_chan_nvc0;
+                        else
+                                *func = abi16_chan_nve0;
+                        return true;
+                }
+        } else
+        if ((parent->length != 0 &&
+             parent->oclass == NOUVEAU_FIFO_CHANNEL_CLASS)) {
+                if (obj->oclass == NOUVEAU_NOTIFIER_CLASS) {
+                        *func = abi16_ntfy;
+                        return true;
+                }
+
+                *func = abi16_engobj;
+                return false; /* try NVIF, if supported, before calling func */
+        }
+
+        *func = NULL;
+        return false;
+}
+
+drm_private void
 abi16_bo_info(struct nouveau_bo *bo, struct drm_nouveau_gem_info *info)
 {
         struct nouveau_bo_priv *nvbo = nouveau_bo(bo);
diff --git a/nouveau/nouveau.c b/nouveau/nouveau.c
index 97fd77b9..8a0be2fa 100644
--- a/nouveau/nouveau.c
+++ b/nouveau/nouveau.c
@@ -135,6 +135,7 @@ nouveau_device_wrap(int fd, int close, struct nouveau_device **pdev)
                 nvdev->gart_limit_percent = 80;
         DRMINITLISTHEAD(&nvdev->bo_list);
         nvdev->base.object.oclass = NOUVEAU_DEVICE_CLASS;
+        nvdev->base.object.length = ~0;
         nvdev->base.lib_version = 0x01000000;
         nvdev->base.chipset = chipset;
         nvdev->base.vram_size = vram;
@@ -251,8 +252,8 @@ nouveau_object_new(struct nouveau_object *parent, uint64_t handle,
                    uint32_t oclass, void *data, uint32_t length,
                    struct nouveau_object **pobj)
 {
-        struct nouveau_device *dev;
         struct nouveau_object *obj;
+        int (*func)(struct nouveau_object *);
         int ret = -EINVAL;
 
         if (length == 0)
@@ -267,37 +268,9 @@ nouveau_object_new(struct nouveau_object *parent, uint64_t handle,
                 memcpy(obj->data, data, length);
         *(struct nouveau_object **)obj->data = obj;
 
-        dev = nouveau_object_find(obj, NOUVEAU_DEVICE_CLASS);
-        switch (parent->oclass) {
-        case NOUVEAU_DEVICE_CLASS:
-                switch (obj->oclass) {
-                case NOUVEAU_FIFO_CHANNEL_CLASS:
-                {
-                        if (dev->chipset < 0xc0)
-                                ret = abi16_chan_nv04(obj);
-                        else
-                        if (dev->chipset < 0xe0)
-                                ret = abi16_chan_nvc0(obj);
-                        else
-                                ret = abi16_chan_nve0(obj);
-                }
-                        break;
-                default:
-                        break;
-                }
-                break;
-        case NOUVEAU_FIFO_CHANNEL_CLASS:
-                switch (obj->oclass) {
-                case NOUVEAU_NOTIFIER_CLASS:
-                        ret = abi16_ntfy(obj);
-                        break;
-                default:
-                        ret = abi16_engobj(obj);
-                        break;
-                }
-        default:
-                break;
-        }
+        abi16_object(obj, &func);
+        if (func)
+                ret = func(obj);
 
         if (ret) {
                 free(obj);
@@ -312,24 +285,11 @@ void
 nouveau_object_del(struct nouveau_object **pobj)
 {
         struct nouveau_object *obj = *pobj;
-        struct nouveau_device *dev;
         if (obj) {
-                dev = nouveau_object_find(obj, NOUVEAU_DEVICE_CLASS);
-                if (obj->oclass == NOUVEAU_FIFO_CHANNEL_CLASS) {
-                        struct drm_nouveau_channel_free req;
-                        req.channel = obj->handle;
-                        drmCommandWrite(dev->fd, DRM_NOUVEAU_CHANNEL_FREE,
-                                        &req, sizeof(req));
-                } else {
-                        struct drm_nouveau_gpuobj_free req;
-                        req.channel = obj->parent->handle;
-                        req.handle  = obj->handle;
-                        drmCommandWrite(dev->fd, DRM_NOUVEAU_GPUOBJ_FREE,
-                                        &req, sizeof(req));
-                }
+                abi16_delete(obj);
+                free(obj);
+                *pobj = NULL;
         }
-        free(obj);
-        *pobj = NULL;
 }
 
 void *
diff --git a/nouveau/private.h b/nouveau/private.h
index e9439f30..5f352a49 100644
--- a/nouveau/private.h
+++ b/nouveau/private.h
@@ -114,11 +114,8 @@ int
 nouveau_device_open_existing(struct nouveau_device **, int, int, drm_context_t);
 
 /* abi16.c */
-drm_private int  abi16_chan_nv04(struct nouveau_object *);
-drm_private int  abi16_chan_nvc0(struct nouveau_object *);
-drm_private int  abi16_chan_nve0(struct nouveau_object *);
-drm_private int  abi16_engobj(struct nouveau_object *);
-drm_private int  abi16_ntfy(struct nouveau_object *);
+drm_private bool abi16_object(struct nouveau_object *, int (**)(struct nouveau_object *));
+drm_private void abi16_delete(struct nouveau_object *);
 drm_private void abi16_bo_info(struct nouveau_bo *, struct drm_nouveau_gem_info *);
 drm_private int  abi16_bo_init(struct nouveau_bo *, uint32_t alignment,
                                union nouveau_bo_config *);