From 6f2479c67432f764bfc4e248689f1737c1935237 Mon Sep 17 00:00:00 2001
From: Robert Noland <rnoland@2hip.net>
Date: Sat, 6 Sep 2008 18:37:06 -0400
Subject: [PATCH] [FreeBSD] Ensure that drm_pci_alloc is never called while
 locks are held.

---
 bsd-core/ati_pcigart.c   | 13 +++++++++----
 bsd-core/drm_bufs.c      |  2 ++
 bsd-core/drm_pci.c       | 13 +++++++++----
 shared-core/i915_dma.c   | 20 ++++++++++++++------
 shared-core/mach64_dma.c |  6 ++++++
 5 files changed, 40 insertions(+), 14 deletions(-)

diff --git a/bsd-core/ati_pcigart.c b/bsd-core/ati_pcigart.c
index f8d3f18..c4453ed 100644
--- a/bsd-core/ati_pcigart.c
+++ b/bsd-core/ati_pcigart.c
@@ -42,12 +42,17 @@
 static int drm_ati_alloc_pcigart_table(struct drm_device *dev,
 				       struct drm_ati_pcigart_info *gart_info)
 {
-	dev->sg->dmah = drm_pci_alloc(dev, gart_info->table_size,
-						PAGE_SIZE,
-						gart_info->table_mask);
-	if (dev->sg->dmah == NULL)
+	drm_dma_handle_t *dmah;
+
+	DRM_UNLOCK();
+	dmah = drm_pci_alloc(dev, gart_info->table_size, PAGE_SIZE,
+	    gart_info->table_mask);
+	DRM_LOCK();
+	if (dmah == NULL)
 		return ENOMEM;
 
+	dev->sg->dmah = dmah;
+
 	return 0;
 }
 
diff --git a/bsd-core/drm_bufs.c b/bsd-core/drm_bufs.c
index 45e0147..94f5138 100644
--- a/bsd-core/drm_bufs.c
+++ b/bsd-core/drm_bufs.c
@@ -595,8 +595,10 @@ static int drm_do_addbufs_pci(struct drm_device *dev, struct drm_buf_desc *reque
 	page_count = 0;
 
 	while (entry->buf_count < count) {
+		DRM_SPINUNLOCK(&dev->dma_lock);
 		drm_dma_handle_t *dmah = drm_pci_alloc(dev, size, alignment,
 		    0xfffffffful);
+		DRM_SPINLOCK(&dev->dma_lock);
 		if (dmah == NULL) {
 			/* Set count correctly so we free the proper amount. */
 			entry->buf_count = count;
diff --git a/bsd-core/drm_pci.c b/bsd-core/drm_pci.c
index f23b2a5..16c830e 100644
--- a/bsd-core/drm_pci.c
+++ b/bsd-core/drm_pci.c
@@ -71,7 +71,14 @@ drm_pci_alloc(struct drm_device *dev, size_t size,
 		return NULL;
 
 #ifdef __FreeBSD__
-	DRM_UNLOCK();
+	/* Make sure we aren't holding locks here */
+	mtx_assert(&dev->dev_lock, MA_NOTOWNED);
+	if (mtx_owned(&dev->dev_lock))
+	    DRM_ERROR("called while holding dev_lock\n");
+	mtx_assert(&dev->dma_lock, MA_NOTOWNED);
+	if (mtx_owned(&dev->dma_lock))
+	    DRM_ERROR("called while holding dma_lock\n");
+
 	ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */
 	    maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */
 	    NULL, NULL, /* filtfunc, filtfuncargs */
@@ -80,7 +87,6 @@ drm_pci_alloc(struct drm_device *dev, size_t size,
 	    &dmah->tag);
 	if (ret != 0) {
 		free(dmah, M_DRM);
-		DRM_LOCK();
 		return NULL;
 	}
 
@@ -89,10 +95,9 @@ drm_pci_alloc(struct drm_device *dev, size_t size,
 	if (ret != 0) {
 		bus_dma_tag_destroy(dmah->tag);
 		free(dmah, M_DRM);
-		DRM_LOCK();
 		return NULL;
 	}
-	DRM_LOCK();
+
 	ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size,
 	    drm_pci_busdma_callback, dmah, 0);
 	if (ret != 0) {
diff --git a/shared-core/i915_dma.c b/shared-core/i915_dma.c
index c874ce2..619e6ac 100644
--- a/shared-core/i915_dma.c
+++ b/shared-core/i915_dma.c
@@ -72,16 +72,24 @@ int i915_wait_ring(struct drm_device * dev, int n, const char *caller)
 int i915_init_hardware_status(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = dev->dev_private;
-	/* Program Hardware Status Page */
-	dev_priv->status_page_dmah =
-		drm_pci_alloc(dev, PAGE_SIZE, PAGE_SIZE, 0xffffffff);
+	drm_dma_handle_t *dmah;
 
-	if (!dev_priv->status_page_dmah) {
+	/* Program Hardware Status Page */
+#ifdef __FreeBSD__
+	DRM_UNLOCK();
+#endif
+	dmah = drm_pci_alloc(dev, PAGE_SIZE, PAGE_SIZE, 0xffffffff);
+#ifdef __FreeBSD__
+	DRM_LOCK();
+#endif
+	if (!dmah) {
 		DRM_ERROR("Can not allocate hardware status page\n");
 		return -ENOMEM;
 	}
-	dev_priv->hw_status_page = dev_priv->status_page_dmah->vaddr;
-	dev_priv->dma_status_page = dev_priv->status_page_dmah->busaddr;
+
+	dev_priv->status_page_dmah = dmah;
+	dev_priv->hw_status_page = dmah->vaddr;
+	dev_priv->dma_status_page = dmah->busaddr;
 
 	memset(dev_priv->hw_status_page, 0, PAGE_SIZE);
 
diff --git a/shared-core/mach64_dma.c b/shared-core/mach64_dma.c
index 339234f..3f2367b 100644
--- a/shared-core/mach64_dma.c
+++ b/shared-core/mach64_dma.c
@@ -834,8 +834,14 @@ static int mach64_bm_dma_test(struct drm_device * dev)
 
 	/* FIXME: get a dma buffer from the freelist here */
 	DRM_DEBUG("Allocating data memory ...\n");
+#ifdef __FreeBSD__
+	DRM_UNLOCK();
+#endif
 	cpu_addr_dmah =
 	    drm_pci_alloc(dev, 0x1000, 0x1000, 0xfffffffful);
+#ifdef __FreeBSD__
+	DRM_LOCK();
+#endif
 	if (!cpu_addr_dmah) {
 		DRM_INFO("data-memory allocation failed!\n");
 		return -ENOMEM;
-- 
2.7.4