drm/i915: add a context parameter to {en, dis}able zero address mapping

Export a new context parameter that can be set/queried through the
context_{get,set}param ioctls.  This parameter is passed as a context
flag and decides whether or not a GPU address mapping is allowed to
be made at address zero.  The default is to allow such mappings.

Signed-off-by: David Weinehall <david.weinehall@intel.com>
Acked-by: "Zou, Nanhai" <nanhai.zou@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 72f5a3f9dbf243c2da93a4151454eb33ff638274..d35b592c7378a438ba6c0536f3ee00e3611cf07a 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -805,11 +805,15 @@ struct i915_ctx_hang_stats {
 
 /* This must match up with the value previously used for execbuf2.rsvd1. */
 #define DEFAULT_CONTEXT_HANDLE 0
+
+#define CONTEXT_NO_ZEROMAP (1<<0)
 /**
  * struct intel_context - as the name implies, represents a context.
  * @ref: reference count.
  * @user_handle: userspace tracking identity for this context.
  * @remap_slice: l3 row remapping information.
+ * @flags: context specific flags:
+ *         CONTEXT_NO_ZEROMAP: do not allow mapping things to page 0.
  * @file_priv: filp associated with this context (NULL for global default
  *            context).
  * @hang_stats: information about the role of this context in possible GPU
@@ -826,6 +830,7 @@ struct intel_context {
        struct kref ref;
        int user_handle;
        uint8_t remap_slice;
+       int flags;
        struct drm_i915_file_private *file_priv;
        struct i915_ctx_hang_stats hang_stats;
        struct i915_hw_ppgtt *ppgtt;

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 8867818b140173fc3c107b299a7b553a6287f8f9..133afcf4d79e4d64777b8e694af5b42a861ac757 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -900,6 +900,9 @@ int i915_gem_context_getparam_ioctl(struct drm_device *dev, void *data,
        case I915_CONTEXT_PARAM_BAN_PERIOD:
                args->value = ctx->hang_stats.ban_period_seconds;
                break;
+       case I915_CONTEXT_PARAM_NO_ZEROMAP:
+               args->value = ctx->flags & CONTEXT_NO_ZEROMAP;
+               break;
        default:
                ret = -EINVAL;
                break;
@@ -937,6 +940,14 @@ int i915_gem_context_setparam_ioctl(struct drm_device *dev, void *data,
                else
                        ctx->hang_stats.ban_period_seconds = args->value;
                break;
+       case I915_CONTEXT_PARAM_NO_ZEROMAP:
+               if (args->size) {
+                       ret = -EINVAL;
+               } else {
+                       ctx->flags &= ~CONTEXT_NO_ZEROMAP;
+                       ctx->flags |= args->value ? CONTEXT_NO_ZEROMAP : 0;
+               }
+               break;
        default:
                ret = -EINVAL;
                break;

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index bd0e4bda2c649a54bb97a1b791ecb6d52e4438f1..3336e1c2c0a5e9c2e589a966fc4898662cf91ed2 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -676,6 +676,7 @@ eb_vma_misplaced(struct i915_vma *vma)
 static int
 i915_gem_execbuffer_reserve(struct intel_engine_cs *ring,
                            struct list_head *vmas,
+                           struct intel_context *ctx,
                            bool *need_relocs)
 {
        struct drm_i915_gem_object *obj;
@@ -698,6 +699,9 @@ i915_gem_execbuffer_reserve(struct intel_engine_cs *ring,
                obj = vma->obj;
                entry = vma->exec_entry;
 
+               if (ctx->flags & CONTEXT_NO_ZEROMAP)
+                       entry->flags |= __EXEC_OBJECT_NEEDS_BIAS;
+
                if (!has_fenced_gpu_access)
                        entry->flags &= ~EXEC_OBJECT_NEEDS_FENCE;
                need_fence =
@@ -775,7 +779,8 @@ i915_gem_execbuffer_relocate_slow(struct drm_device *dev,
                                  struct drm_file *file,
                                  struct intel_engine_cs *ring,
                                  struct eb_vmas *eb,
-                                 struct drm_i915_gem_exec_object2 *exec)
+                                 struct drm_i915_gem_exec_object2 *exec,
+                                 struct intel_context *ctx)
 {
        struct drm_i915_gem_relocation_entry *reloc;
        struct i915_address_space *vm;
@@ -861,7 +866,7 @@ i915_gem_execbuffer_relocate_slow(struct drm_device *dev,
                goto err;
 
        need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
-       ret = i915_gem_execbuffer_reserve(ring, &eb->vmas, &need_relocs);
+       ret = i915_gem_execbuffer_reserve(ring, &eb->vmas, ctx, &need_relocs);
        if (ret)
                goto err;
 
@@ -1519,7 +1524,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 
        /* Move the objects en-masse into the GTT, evicting if necessary. */
        need_relocs = (args->flags & I915_EXEC_NO_RELOC) == 0;
-       ret = i915_gem_execbuffer_reserve(ring, &eb->vmas, &need_relocs);
+       ret = i915_gem_execbuffer_reserve(ring, &eb->vmas, ctx, &need_relocs);
        if (ret)
                goto err;
 
@@ -1529,7 +1534,7 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
        if (ret) {
                if (ret == -EFAULT) {
                        ret = i915_gem_execbuffer_relocate_slow(dev, args, file, ring,
-                                                               eb, exec);
+                                                               eb, exec, ctx);
                        BUG_ON(!mutex_is_locked(&dev->struct_mutex));
                }
                if (ret)

diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 6e1a2ed116cb1410958f61631a7dc30839652738..92d61a7c942a905976ded3c30aa5066ab832f1fb 100644 (file)
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -1106,6 +1106,7 @@ struct drm_i915_gem_context_param {
        __u32 size;
        __u64 param;
 #define I915_CONTEXT_PARAM_BAN_PERIOD 0x1
+#define I915_CONTEXT_PARAM_NO_ZEROMAP 0x2
        __u64 value;
 };