6 files changed, 87 insertions, 45 deletions

diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index 93f4d059fc89..1e1cb245fca7 100644
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -20,7 +20,6 @@ config DRM_I915
 	select INPUT if ACPI
 	select ACPI_VIDEO if ACPI
 	select ACPI_BUTTON if ACPI
-	select IO_MAPPING
 	select SYNC_FILE
 	select IOSF_MBI
 	select CRC32
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index 02a003fd48fb..50cae0198a3d 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -128,49 +128,13 @@ intel_dp_set_lttpr_transparent_mode(struct intel_dp *intel_dp, bool enable)
 	return drm_dp_dpcd_write(&intel_dp->aux, DP_PHY_REPEATER_MODE, &val, 1) == 1;
 }
 
-/**
- * intel_dp_init_lttpr_and_dprx_caps - detect LTTPR and DPRX caps, init the LTTPR link training mode
- * @intel_dp: Intel DP struct
- *
- * Read the LTTPR common and DPRX capabilities and switch to non-transparent
- * link training mode if any is detected and read the PHY capabilities for all
- * detected LTTPRs. In case of an LTTPR detection error or if the number of
- * LTTPRs is more than is supported (8), fall back to the no-LTTPR,
- * transparent mode link training mode.
- *
- * Returns:
- *   >0  if LTTPRs were detected and the non-transparent LT mode was set. The
- *       DPRX capabilities are read out.
- *    0  if no LTTPRs or more than 8 LTTPRs were detected or in case of a
- *       detection failure and the transparent LT mode was set. The DPRX
- *       capabilities are read out.
- *   <0  Reading out the DPRX capabilities failed.
- */
-int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp)
+static int intel_dp_init_lttpr(struct intel_dp *intel_dp)
 {
 	int lttpr_count;
-	bool ret;
 	int i;
 
-	ret = intel_dp_read_lttpr_common_caps(intel_dp);
-
-	/* The DPTX shall read the DPRX caps after LTTPR detection. */
-	if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd)) {
-		intel_dp_reset_lttpr_common_caps(intel_dp);
-		return -EIO;
-	}
-
-	if (!ret)
-		return 0;
-
-	/*
-	 * The 0xF0000-0xF02FF range is only valid if the DPCD revision is
-	 * at least 1.4.
-	 */
-	if (intel_dp->dpcd[DP_DPCD_REV] < 0x14) {
-		intel_dp_reset_lttpr_common_caps(intel_dp);
+	if (!intel_dp_read_lttpr_common_caps(intel_dp))
 		return 0;
-	}
 
 	lttpr_count = drm_dp_lttpr_count(intel_dp->lttpr_common_caps);
 	/*
@@ -211,6 +175,37 @@ int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp)
 
 	return lttpr_count;
 }
+
+/**
+ * intel_dp_init_lttpr_and_dprx_caps - detect LTTPR and DPRX caps, init the LTTPR link training mode
+ * @intel_dp: Intel DP struct
+ *
+ * Read the LTTPR common and DPRX capabilities and switch to non-transparent
+ * link training mode if any is detected and read the PHY capabilities for all
+ * detected LTTPRs. In case of an LTTPR detection error or if the number of
+ * LTTPRs is more than is supported (8), fall back to the no-LTTPR,
+ * transparent mode link training mode.
+ *
+ * Returns:
+ *   >0  if LTTPRs were detected and the non-transparent LT mode was set. The
+ *       DPRX capabilities are read out.
+ *    0  if no LTTPRs or more than 8 LTTPRs were detected or in case of a
+ *       detection failure and the transparent LT mode was set. The DPRX
+ *       capabilities are read out.
+ *   <0  Reading out the DPRX capabilities failed.
+ */
+int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp)
+{
+	int lttpr_count = intel_dp_init_lttpr(intel_dp);
+
+	/* The DPTX shall read the DPRX caps after LTTPR detection. */
+	if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd)) {
+		intel_dp_reset_lttpr_common_caps(intel_dp);
+		return -EIO;
+	}
+
+	return lttpr_count;
+}
 EXPORT_SYMBOL(intel_dp_init_lttpr_and_dprx_caps);
 
 static u8 dp_voltage_max(u8 preemph)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index f6fe5cb01438..8598a1c78a4c 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -367,10 +367,11 @@ retry:
 		goto err_unpin;
 
 	/* Finally, remap it using the new GTT offset */
-	ret = io_mapping_map_user(&ggtt->iomap, area, area->vm_start +
-			(vma->ggtt_view.partial.offset << PAGE_SHIFT),
-			(ggtt->gmadr.start + vma->node.start) >> PAGE_SHIFT,
-			min_t(u64, vma->size, area->vm_end - area->vm_start));
+	ret = remap_io_mapping(area,
+			       area->vm_start + (vma->ggtt_view.partial.offset << PAGE_SHIFT),
+			       (ggtt->gmadr.start + vma->node.start) >> PAGE_SHIFT,
+			       min_t(u64, vma->size, area->vm_end - area->vm_start),
+			       &ggtt->iomap);
 	if (ret)
 		goto err_fence;
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 9ec9277539ec..69e43bf91a15 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1905,6 +1905,9 @@ int i915_reg_read_ioctl(struct drm_device *dev, void *data,
 			struct drm_file *file);
 
 /* i915_mm.c */
+int remap_io_mapping(struct vm_area_struct *vma,
+		     unsigned long addr, unsigned long pfn, unsigned long size,
+		     struct io_mapping *iomap);
 int remap_io_sg(struct vm_area_struct *vma,
 		unsigned long addr, unsigned long size,
 		struct scatterlist *sgl, resource_size_t iobase);
diff --git a/drivers/gpu/drm/i915/i915_mm.c b/drivers/gpu/drm/i915/i915_mm.c
index 9a777b0ff59b..666808cb3a32 100644
--- a/drivers/gpu/drm/i915/i915_mm.c
+++ b/drivers/gpu/drm/i915/i915_mm.c
@@ -37,6 +37,17 @@ struct remap_pfn {
 	resource_size_t iobase;
 };
 
+static int remap_pfn(pte_t *pte, unsigned long addr, void *data)
+{
+	struct remap_pfn *r = data;
+
+	/* Special PTE are not associated with any struct page */
+	set_pte_at(r->mm, addr, pte, pte_mkspecial(pfn_pte(r->pfn, r->prot)));
+	r->pfn++;
+
+	return 0;
+}
+
 #define use_dma(io) ((io) != -1)
 
 static inline unsigned long sgt_pfn(const struct remap_pfn *r)
@@ -66,7 +77,40 @@ static int remap_sg(pte_t *pte, unsigned long addr, void *data)
 	return 0;
 }
 
+/**
+ * remap_io_mapping - remap an IO mapping to userspace
+ * @vma: user vma to map to
+ * @addr: target user address to start at
+ * @pfn: physical address of kernel memory
+ * @size: size of map area
+ * @iomap: the source io_mapping
+ *
+ *  Note: this is only safe if the mm semaphore is held when called.
+ */
+int remap_io_mapping(struct vm_area_struct *vma,
+		     unsigned long addr, unsigned long pfn, unsigned long size,
+		     struct io_mapping *iomap)
+{
+	struct remap_pfn r;
+	int err;
+
 #define EXPECTED_FLAGS (VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP)
+	GEM_BUG_ON((vma->vm_flags & EXPECTED_FLAGS) != EXPECTED_FLAGS);
+
+	/* We rely on prevalidation of the io-mapping to skip track_pfn(). */
+	r.mm = vma->vm_mm;
+	r.pfn = pfn;
+	r.prot = __pgprot((pgprot_val(iomap->prot) & _PAGE_CACHE_MASK) |
+			  (pgprot_val(vma->vm_page_prot) & ~_PAGE_CACHE_MASK));
+
+	err = apply_to_page_range(r.mm, addr, size, remap_pfn, &r);
+	if (unlikely(err)) {
+		zap_vma_ptes(vma, addr, (r.pfn - pfn) << PAGE_SHIFT);
+		return err;
+	}
+
+	return 0;
+}
 
 /**
  * remap_io_sg - remap an IO mapping to userspace
diff --git a/drivers/gpu/drm/i915/selftests/i915_request.c b/drivers/gpu/drm/i915/selftests/i915_request.c
index ee8e753d98ce..eae0abd614cb 100644
--- a/drivers/gpu/drm/i915/selftests/i915_request.c
+++ b/drivers/gpu/drm/i915/selftests/i915_request.c
@@ -1592,8 +1592,8 @@ static int live_breadcrumbs_smoketest(void *arg)
 
 	for (n = 0; n < smoke[0].ncontexts; n++) {
 		smoke[0].contexts[n] = live_context(i915, file);
-		if (!smoke[0].contexts[n]) {
-			ret = -ENOMEM;
+		if (IS_ERR(smoke[0].contexts[n])) {
+			ret = PTR_ERR(smoke[0].contexts[n]);
 			goto out_contexts;
 		}
 	}