drm/nouveau: add per-channel mutex, use to lock access to drm's channel
This fixes a race condition between fbcon acceleration and TTM buffer
moves. To reproduce:
- start X
- switch to vt and "while (true); do dmesg; done"
- switch to another vt and "sleep 2 && cat /path/to/debugfs/dri/0/evict_vram"
- switch back to vt running dmesg
We don't make use of this on any other channel yet, they're currently
protected by drm_global_mutex. This will change in the near future.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index c41e1c2..d8817b4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -683,17 +683,24 @@
int ret;
chan = nvbo->channel;
- if (!chan || nvbo->no_vm)
+ if (!chan || nvbo->no_vm) {
chan = dev_priv->channel;
+ mutex_lock(&chan->mutex);
+ }
if (dev_priv->card_type < NV_50)
ret = nv04_bo_move_m2mf(chan, bo, &bo->mem, new_mem);
else
ret = nv50_bo_move_m2mf(chan, bo, &bo->mem, new_mem);
- if (ret)
- return ret;
+ if (ret == 0) {
+ ret = nouveau_bo_move_accel_cleanup(chan, nvbo, evict,
+ no_wait_reserve,
+ no_wait_gpu, new_mem);
+ }
- return nouveau_bo_move_accel_cleanup(chan, nvbo, evict, no_wait_reserve, no_wait_gpu, new_mem);
+ if (chan == dev_priv->channel)
+ mutex_unlock(&chan->mutex);
+ return ret;
}
static int
diff --git a/drivers/gpu/drm/nouveau/nouveau_channel.c b/drivers/gpu/drm/nouveau/nouveau_channel.c
index 373950e..8636478 100644
--- a/drivers/gpu/drm/nouveau/nouveau_channel.c
+++ b/drivers/gpu/drm/nouveau/nouveau_channel.c
@@ -145,6 +145,7 @@
chan->file_priv = file_priv;
chan->vram_handle = vram_handle;
chan->gart_handle = tt_handle;
+ mutex_init(&chan->mutex);
NV_INFO(dev, "Allocating FIFO number %d\n", channel);
diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h
index 1c7db64..04bc56c 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drv.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drv.h
@@ -166,6 +166,8 @@
struct drm_device *dev;
int id;
+ struct mutex mutex;
+
/* owner of this fifo */
struct drm_file *file_priv;
/* mapping of the fifo itself */
diff --git a/drivers/gpu/drm/nouveau/nouveau_fbcon.c b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
index 22e83ad..bc30dbe 100644
--- a/drivers/gpu/drm/nouveau/nouveau_fbcon.c
+++ b/drivers/gpu/drm/nouveau/nouveau_fbcon.c
@@ -62,11 +62,13 @@
ret = -ENODEV;
if (!in_interrupt() && !(info->flags & FBINFO_HWACCEL_DISABLED)) {
+ mutex_lock(&dev_priv->channel->mutex);
if (dev_priv->card_type < NV_50)
ret = nv04_fbcon_fillrect(info, rect);
else
if (dev_priv->card_type < NV_C0)
ret = nv50_fbcon_fillrect(info, rect);
+ mutex_unlock(&dev_priv->channel->mutex);
}
if (ret == 0)
@@ -90,11 +92,13 @@
ret = -ENODEV;
if (!in_interrupt() && !(info->flags & FBINFO_HWACCEL_DISABLED)) {
+ mutex_lock(&dev_priv->channel->mutex);
if (dev_priv->card_type < NV_50)
ret = nv04_fbcon_copyarea(info, image);
else
if (dev_priv->card_type < NV_C0)
ret = nv50_fbcon_copyarea(info, image);
+ mutex_unlock(&dev_priv->channel->mutex);
}
if (ret == 0)
@@ -118,11 +122,13 @@
ret = -ENODEV;
if (!in_interrupt() && !(info->flags & FBINFO_HWACCEL_DISABLED)) {
+ mutex_lock(&dev_priv->channel->mutex);
if (dev_priv->card_type < NV_50)
ret = nv04_fbcon_imageblit(info, image);
else
if (dev_priv->card_type < NV_C0)
ret = nv50_fbcon_imageblit(info, image);
+ mutex_unlock(&dev_priv->channel->mutex);
}
if (ret == 0)
@@ -142,12 +148,15 @@
struct nouveau_channel *chan = dev_priv->channel;
int ret, i;
- if (!chan || !chan->accel_done ||
+ if (!chan || !chan->accel_done || in_interrupt() ||
info->state != FBINFO_STATE_RUNNING ||
info->flags & FBINFO_HWACCEL_DISABLED)
return 0;
- if (RING_SPACE(chan, 4)) {
+ mutex_lock(&chan->mutex);
+ ret = RING_SPACE(chan, 4);
+ if (ret) {
+ mutex_unlock(&chan->mutex);
nouveau_fbcon_gpu_lockup(info);
return 0;
}
@@ -158,6 +167,7 @@
OUT_RING(chan, 0);
nouveau_bo_wr32(chan->notifier_bo, chan->m2mf_ntfy + 3, 0xffffffff);
FIRE_RING(chan);
+ mutex_unlock(&chan->mutex);
ret = -EBUSY;
for (i = 0; i < 100000; i++) {
@@ -353,6 +363,8 @@
info->pixmap.flags = FB_PIXMAP_SYSTEM;
info->pixmap.scan_align = 1;
+ mutex_unlock(&dev->struct_mutex);
+
if (dev_priv->channel && !nouveau_nofbaccel) {
ret = -ENODEV;
if (dev_priv->card_type < NV_50)
@@ -373,7 +385,6 @@
nouveau_fb->base.height,
nvbo->bo.offset, nvbo);
- mutex_unlock(&dev->struct_mutex);
vga_switcheroo_client_fb_set(dev->pdev, info);
return 0;
