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authorSushmita Susheelendra <ssusheel@codeaurora.org>2017-06-13 16:52:54 -0600
committerRob Clark <robdclark@gmail.com>2017-06-17 08:03:07 -0400
commit0e08270a1f01bceae17d32a0d75aad2388bd1ba2 (patch)
tree31f17b04f1a459ca5ab26772626c8ece4c54158a /drivers
parent816fa34c051492c7f115ad2fd91c9e723d7fc298 (diff)
downloadlwn-0e08270a1f01bceae17d32a0d75aad2388bd1ba2.tar.gz
lwn-0e08270a1f01bceae17d32a0d75aad2388bd1ba2.zip
drm/msm: Separate locking of buffer resources from struct_mutex
Buffer object specific resources like pages, domains, sg list need not be protected with struct_mutex. They can be protected with a buffer object level lock. This simplifies locking and makes it easier to avoid potential recursive locking scenarios for SVM involving mmap_sem and struct_mutex. This also removes unnecessary serialization when creating buffer objects, and also between buffer object creation and GPU command submission. Signed-off-by: Sushmita Susheelendra <ssusheel@codeaurora.org> [robclark: squash in handling new locking for shrinker] Signed-off-by: Rob Clark <robdclark@gmail.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/gpu/drm/msm/adreno/a5xx_gpu.c8
-rw-r--r--drivers/gpu/drm/msm/adreno/a5xx_power.c8
-rw-r--r--drivers/gpu/drm/msm/adreno/adreno_gpu.c4
-rw-r--r--drivers/gpu/drm/msm/dsi/dsi_host.c4
-rw-r--r--drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c2
-rw-r--r--drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c2
-rw-r--r--drivers/gpu/drm/msm/msm_drv.c1
-rw-r--r--drivers/gpu/drm/msm/msm_drv.h9
-rw-r--r--drivers/gpu/drm/msm/msm_fbdev.c6
-rw-r--r--drivers/gpu/drm/msm/msm_gem.c274
-rw-r--r--drivers/gpu/drm/msm/msm_gem.h22
-rw-r--r--drivers/gpu/drm/msm/msm_gem_shrinker.c16
-rw-r--r--drivers/gpu/drm/msm/msm_gem_submit.c6
-rw-r--r--drivers/gpu/drm/msm/msm_gem_vma.c10
-rw-r--r--drivers/gpu/drm/msm/msm_gpu.c4
-rw-r--r--drivers/gpu/drm/msm/msm_rd.c4
-rw-r--r--drivers/gpu/drm/msm/msm_ringbuffer.c2
17 files changed, 238 insertions, 144 deletions
diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
index f6a9eec71fec..b4b54f1c24bc 100644
--- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
@@ -297,18 +297,18 @@ static struct drm_gem_object *a5xx_ucode_load_bo(struct msm_gpu *gpu,
struct drm_gem_object *bo;
void *ptr;
- bo = msm_gem_new(drm, fw->size - 4, MSM_BO_UNCACHED);
+ bo = msm_gem_new_locked(drm, fw->size - 4, MSM_BO_UNCACHED);
if (IS_ERR(bo))
return bo;
- ptr = msm_gem_get_vaddr_locked(bo);
+ ptr = msm_gem_get_vaddr(bo);
if (!ptr) {
drm_gem_object_unreference(bo);
return ERR_PTR(-ENOMEM);
}
if (iova) {
- int ret = msm_gem_get_iova_locked(bo, gpu->aspace, iova);
+ int ret = msm_gem_get_iova(bo, gpu->aspace, iova);
if (ret) {
drm_gem_object_unreference(bo);
@@ -318,7 +318,7 @@ static struct drm_gem_object *a5xx_ucode_load_bo(struct msm_gpu *gpu,
memcpy(ptr, &fw->data[4], fw->size - 4);
- msm_gem_put_vaddr_locked(bo);
+ msm_gem_put_vaddr(bo);
return bo;
}
diff --git a/drivers/gpu/drm/msm/adreno/a5xx_power.c b/drivers/gpu/drm/msm/adreno/a5xx_power.c
index feb7f4fd42fb..87af6eea0483 100644
--- a/drivers/gpu/drm/msm/adreno/a5xx_power.c
+++ b/drivers/gpu/drm/msm/adreno/a5xx_power.c
@@ -294,15 +294,15 @@ void a5xx_gpmu_ucode_init(struct msm_gpu *gpu)
*/
bosize = (cmds_size + (cmds_size / TYPE4_MAX_PAYLOAD) + 1) << 2;
- a5xx_gpu->gpmu_bo = msm_gem_new(drm, bosize, MSM_BO_UNCACHED);
+ a5xx_gpu->gpmu_bo = msm_gem_new_locked(drm, bosize, MSM_BO_UNCACHED);
if (IS_ERR(a5xx_gpu->gpmu_bo))
goto err;
- if (msm_gem_get_iova_locked(a5xx_gpu->gpmu_bo, gpu->aspace,
+ if (msm_gem_get_iova(a5xx_gpu->gpmu_bo, gpu->aspace,
&a5xx_gpu->gpmu_iova))
goto err;
- ptr = msm_gem_get_vaddr_locked(a5xx_gpu->gpmu_bo);
+ ptr = msm_gem_get_vaddr(a5xx_gpu->gpmu_bo);
if (!ptr)
goto err;
@@ -321,7 +321,7 @@ void a5xx_gpmu_ucode_init(struct msm_gpu *gpu)
cmds_size -= _size;
}
- msm_gem_put_vaddr_locked(a5xx_gpu->gpmu_bo);
+ msm_gem_put_vaddr(a5xx_gpu->gpmu_bo);
a5xx_gpu->gpmu_dwords = dwords;
goto out;
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index 6fa694e6ae8c..f1ab2703674a 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -64,7 +64,7 @@ int adreno_hw_init(struct msm_gpu *gpu)
DBG("%s", gpu->name);
- ret = msm_gem_get_iova_locked(gpu->rb->bo, gpu->aspace, &gpu->rb_iova);
+ ret = msm_gem_get_iova(gpu->rb->bo, gpu->aspace, &gpu->rb_iova);
if (ret) {
gpu->rb_iova = 0;
dev_err(gpu->dev->dev, "could not map ringbuffer: %d\n", ret);
@@ -397,10 +397,8 @@ int adreno_gpu_init(struct drm_device *drm, struct platform_device *pdev,
return ret;
}
- mutex_lock(&drm->struct_mutex);
adreno_gpu->memptrs_bo = msm_gem_new(drm, sizeof(*adreno_gpu->memptrs),
MSM_BO_UNCACHED);
- mutex_unlock(&drm->struct_mutex);
if (IS_ERR(adreno_gpu->memptrs_bo)) {
ret = PTR_ERR(adreno_gpu->memptrs_bo);
adreno_gpu->memptrs_bo = NULL;
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 2e7077194b21..9e9c5696bc03 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -982,18 +982,16 @@ static int dsi_tx_buf_alloc(struct msm_dsi_host *msm_host, int size)
uint64_t iova;
if (cfg_hnd->major == MSM_DSI_VER_MAJOR_6G) {
- mutex_lock(&dev->struct_mutex);
msm_host->tx_gem_obj = msm_gem_new(dev, size, MSM_BO_UNCACHED);
if (IS_ERR(msm_host->tx_gem_obj)) {
ret = PTR_ERR(msm_host->tx_gem_obj);
pr_err("%s: failed to allocate gem, %d\n",
__func__, ret);
msm_host->tx_gem_obj = NULL;
- mutex_unlock(&dev->struct_mutex);
return ret;
}
- ret = msm_gem_get_iova_locked(msm_host->tx_gem_obj,
+ ret = msm_gem_get_iova(msm_host->tx_gem_obj,
priv->kms->aspace, &iova);
mutex_unlock(&dev->struct_mutex);
if (ret) {
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c
index 59153a4ebd18..615e1def64d9 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_crtc.c
@@ -374,7 +374,7 @@ static void update_cursor(struct drm_crtc *crtc)
if (next_bo) {
/* take a obj ref + iova ref when we start scanning out: */
drm_gem_object_reference(next_bo);
- msm_gem_get_iova_locked(next_bo, kms->aspace, &iova);
+ msm_gem_get_iova(next_bo, kms->aspace, &iova);
/* enable cursor: */
mdp4_write(mdp4_kms, REG_MDP4_DMA_CURSOR_SIZE(dma),
diff --git a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
index 3d96687a1b39..bcd1f5cac72c 100644
--- a/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
+++ b/drivers/gpu/drm/msm/mdp/mdp4/mdp4_kms.c
@@ -528,9 +528,7 @@ struct msm_kms *mdp4_kms_init(struct drm_device *dev)
goto fail;
}
- mutex_lock(&dev->struct_mutex);
mdp4_kms->blank_cursor_bo = msm_gem_new(dev, SZ_16K, MSM_BO_WC);
- mutex_unlock(&dev->struct_mutex);
if (IS_ERR(mdp4_kms->blank_cursor_bo)) {
ret = PTR_ERR(mdp4_kms->blank_cursor_bo);
dev_err(dev->dev, "could not allocate blank-cursor bo: %d\n", ret);
diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 506de3862c18..f49f6ac5585c 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -336,6 +336,7 @@ static int msm_init_vram(struct drm_device *dev)
priv->vram.size = size;
drm_mm_init(&priv->vram.mm, 0, (size >> PAGE_SHIFT) - 1);
+ spin_lock_init(&priv->vram.lock);
attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
attrs |= DMA_ATTR_WRITE_COMBINE;
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 1d47ec467ded..fc8d24f7c084 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -149,6 +149,7 @@ struct msm_drm_private {
* and position mm_node->start is in # of pages:
*/
struct drm_mm mm;
+ spinlock_t lock; /* Protects drm_mm node allocation/removal */
} vram;
struct notifier_block vmap_notifier;
@@ -198,8 +199,6 @@ int msm_gem_mmap_obj(struct drm_gem_object *obj,
int msm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
int msm_gem_fault(struct vm_fault *vmf);
uint64_t msm_gem_mmap_offset(struct drm_gem_object *obj);
-int msm_gem_get_iova_locked(struct drm_gem_object *obj,
- struct msm_gem_address_space *aspace, uint64_t *iova);
int msm_gem_get_iova(struct drm_gem_object *obj,
struct msm_gem_address_space *aspace, uint64_t *iova);
uint64_t msm_gem_iova(struct drm_gem_object *obj,
@@ -221,13 +220,9 @@ struct drm_gem_object *msm_gem_prime_import_sg_table(struct drm_device *dev,
struct dma_buf_attachment *attach, struct sg_table *sg);
int msm_gem_prime_pin(struct drm_gem_object *obj);
void msm_gem_prime_unpin(struct drm_gem_object *obj);
-void *msm_gem_get_vaddr_locked(struct drm_gem_object *obj);
void *msm_gem_get_vaddr(struct drm_gem_object *obj);
-void msm_gem_put_vaddr_locked(struct drm_gem_object *obj);
void msm_gem_put_vaddr(struct drm_gem_object *obj);
int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv);
-void msm_gem_purge(struct drm_gem_object *obj);
-void msm_gem_vunmap(struct drm_gem_object *obj);
int msm_gem_sync_object(struct drm_gem_object *obj,
struct msm_fence_context *fctx, bool exclusive);
void msm_gem_move_to_active(struct drm_gem_object *obj,
@@ -240,6 +235,8 @@ int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file,
uint32_t size, uint32_t flags, uint32_t *handle);
struct drm_gem_object *msm_gem_new(struct drm_device *dev,
uint32_t size, uint32_t flags);
+struct drm_gem_object *msm_gem_new_locked(struct drm_device *dev,
+ uint32_t size, uint32_t flags);
struct drm_gem_object *msm_gem_import(struct drm_device *dev,
struct dma_buf *dmabuf, struct sg_table *sgt);
diff --git a/drivers/gpu/drm/msm/msm_fbdev.c b/drivers/gpu/drm/msm/msm_fbdev.c
index 803ed272dc6d..5ecf4ff9a059 100644
--- a/drivers/gpu/drm/msm/msm_fbdev.c
+++ b/drivers/gpu/drm/msm/msm_fbdev.c
@@ -97,10 +97,8 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
/* allocate backing bo */
size = mode_cmd.pitches[0] * mode_cmd.height;
DBG("allocating %d bytes for fb %d", size, dev->primary->index);
- mutex_lock(&dev->struct_mutex);
fbdev->bo = msm_gem_new(dev, size, MSM_BO_SCANOUT |
MSM_BO_WC | MSM_BO_STOLEN);
- mutex_unlock(&dev->struct_mutex);
if (IS_ERR(fbdev->bo)) {
ret = PTR_ERR(fbdev->bo);
fbdev->bo = NULL;
@@ -126,7 +124,7 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
* in panic (ie. lock-safe, etc) we could avoid pinning the
* buffer now:
*/
- ret = msm_gem_get_iova_locked(fbdev->bo, priv->kms->aspace, &paddr);
+ ret = msm_gem_get_iova(fbdev->bo, priv->kms->aspace, &paddr);
if (ret) {
dev_err(dev->dev, "failed to get buffer obj iova: %d\n", ret);
goto fail_unlock;
@@ -155,7 +153,7 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
dev->mode_config.fb_base = paddr;
- fbi->screen_base = msm_gem_get_vaddr_locked(fbdev->bo);
+ fbi->screen_base = msm_gem_get_vaddr(fbdev->bo);
if (IS_ERR(fbi->screen_base)) {
ret = PTR_ERR(fbi->screen_base);
goto fail_unlock;
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 9951c78ee215..65f35544c1ec 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -26,6 +26,9 @@
#include "msm_gpu.h"
#include "msm_mmu.h"
+static void msm_gem_vunmap_locked(struct drm_gem_object *obj);
+
+
static dma_addr_t physaddr(struct drm_gem_object *obj)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
@@ -41,8 +44,7 @@ static bool use_pages(struct drm_gem_object *obj)
}
/* allocate pages from VRAM carveout, used when no IOMMU: */
-static struct page **get_pages_vram(struct drm_gem_object *obj,
- int npages)
+static struct page **get_pages_vram(struct drm_gem_object *obj, int npages)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct msm_drm_private *priv = obj->dev->dev_private;
@@ -54,7 +56,9 @@ static struct page **get_pages_vram(struct drm_gem_object *obj,
if (!p)
return ERR_PTR(-ENOMEM);
+ spin_lock(&priv->vram.lock);
ret = drm_mm_insert_node(&priv->vram.mm, msm_obj->vram_node, npages);
+ spin_unlock(&priv->vram.lock);
if (ret) {
kvfree(p);
return ERR_PTR(ret);
@@ -69,7 +73,6 @@ static struct page **get_pages_vram(struct drm_gem_object *obj,
return p;
}
-/* called with dev->struct_mutex held */
static struct page **get_pages(struct drm_gem_object *obj)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
@@ -109,6 +112,18 @@ static struct page **get_pages(struct drm_gem_object *obj)
return msm_obj->pages;
}
+static void put_pages_vram(struct drm_gem_object *obj)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ struct msm_drm_private *priv = obj->dev->dev_private;
+
+ spin_lock(&priv->vram.lock);
+ drm_mm_remove_node(msm_obj->vram_node);
+ spin_unlock(&priv->vram.lock);
+
+ kvfree(msm_obj->pages);
+}
+
static void put_pages(struct drm_gem_object *obj)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
@@ -125,10 +140,8 @@ static void put_pages(struct drm_gem_object *obj)
if (use_pages(obj))
drm_gem_put_pages(obj, msm_obj->pages, true, false);
- else {
- drm_mm_remove_node(msm_obj->vram_node);
- kvfree(msm_obj->pages);
- }
+ else
+ put_pages_vram(obj);
msm_obj->pages = NULL;
}
@@ -136,11 +149,18 @@ static void put_pages(struct drm_gem_object *obj)
struct page **msm_gem_get_pages(struct drm_gem_object *obj)
{
- struct drm_device *dev = obj->dev;
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct page **p;
- mutex_lock(&dev->struct_mutex);
+
+ mutex_lock(&msm_obj->lock);
+
+ if (WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED)) {
+ mutex_unlock(&msm_obj->lock);
+ return ERR_PTR(-EBUSY);
+ }
+
p = get_pages(obj);
- mutex_unlock(&dev->struct_mutex);
+ mutex_unlock(&msm_obj->lock);
return p;
}
@@ -195,28 +215,25 @@ int msm_gem_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct drm_gem_object *obj = vma->vm_private_data;
- struct drm_device *dev = obj->dev;
- struct msm_drm_private *priv = dev->dev_private;
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct page **pages;
unsigned long pfn;
pgoff_t pgoff;
int ret;
- /* This should only happen if userspace tries to pass a mmap'd
- * but unfaulted gem bo vaddr into submit ioctl, triggering
- * a page fault while struct_mutex is already held. This is
- * not a valid use-case so just bail.
- */
- if (priv->struct_mutex_task == current)
- return VM_FAULT_SIGBUS;
-
- /* Make sure we don't parallel update on a fault, nor move or remove
- * something from beneath our feet
+ /*
+ * vm_ops.open/drm_gem_mmap_obj and close get and put
+ * a reference on obj. So, we dont need to hold one here.
*/
- ret = mutex_lock_interruptible(&dev->struct_mutex);
+ ret = mutex_lock_interruptible(&msm_obj->lock);
if (ret)
goto out;
+ if (WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED)) {
+ mutex_unlock(&msm_obj->lock);
+ return VM_FAULT_SIGBUS;
+ }
+
/* make sure we have pages attached now */
pages = get_pages(obj);
if (IS_ERR(pages)) {
@@ -235,7 +252,7 @@ int msm_gem_fault(struct vm_fault *vmf)
ret = vm_insert_mixed(vma, vmf->address, __pfn_to_pfn_t(pfn, PFN_DEV));
out_unlock:
- mutex_unlock(&dev->struct_mutex);
+ mutex_unlock(&msm_obj->lock);
out:
switch (ret) {
case -EAGAIN:
@@ -259,9 +276,10 @@ out:
static uint64_t mmap_offset(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
int ret;
- WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+ WARN_ON(!mutex_is_locked(&msm_obj->lock));
/* Make it mmapable */
ret = drm_gem_create_mmap_offset(obj);
@@ -277,9 +295,11 @@ static uint64_t mmap_offset(struct drm_gem_object *obj)
uint64_t msm_gem_mmap_offset(struct drm_gem_object *obj)
{
uint64_t offset;
- mutex_lock(&obj->dev->struct_mutex);
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+
+ mutex_lock(&msm_obj->lock);
offset = mmap_offset(obj);
- mutex_unlock(&obj->dev->struct_mutex);
+ mutex_unlock(&msm_obj->lock);
return offset;
}
@@ -289,6 +309,8 @@ static struct msm_gem_vma *add_vma(struct drm_gem_object *obj,
struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct msm_gem_vma *vma;
+ WARN_ON(!mutex_is_locked(&msm_obj->lock));
+
vma = kzalloc(sizeof(*vma), GFP_KERNEL);
if (!vma)
return ERR_PTR(-ENOMEM);
@@ -306,7 +328,7 @@ static struct msm_gem_vma *lookup_vma(struct drm_gem_object *obj,
struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct msm_gem_vma *vma;
- WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+ WARN_ON(!mutex_is_locked(&msm_obj->lock));
list_for_each_entry(vma, &msm_obj->vmas, list) {
if (vma->aspace == aspace)
@@ -325,13 +347,14 @@ static void del_vma(struct msm_gem_vma *vma)
kfree(vma);
}
+/* Called with msm_obj->lock locked */
static void
put_iova(struct drm_gem_object *obj)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct msm_gem_vma *vma, *tmp;
- WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+ WARN_ON(!mutex_is_locked(&msm_obj->lock));
list_for_each_entry_safe(vma, tmp, &msm_obj->vmas, list) {
msm_gem_unmap_vma(vma->aspace, vma, msm_obj->sgt);
@@ -339,21 +362,20 @@ put_iova(struct drm_gem_object *obj)
}
}
-/* should be called under struct_mutex.. although it can be called
- * from atomic context without struct_mutex to acquire an extra
- * iova ref if you know one is already held.
- *
- * That means when I do eventually need to add support for unpinning
- * the refcnt counter needs to be atomic_t.
- */
-int msm_gem_get_iova_locked(struct drm_gem_object *obj,
+/* get iova, taking a reference. Should have a matching put */
+int msm_gem_get_iova(struct drm_gem_object *obj,
struct msm_gem_address_space *aspace, uint64_t *iova)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct msm_gem_vma *vma;
int ret = 0;
- WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+ mutex_lock(&msm_obj->lock);
+
+ if (WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED)) {
+ mutex_unlock(&msm_obj->lock);
+ return -EBUSY;
+ }
vma = lookup_vma(obj, aspace);
@@ -377,24 +399,14 @@ int msm_gem_get_iova_locked(struct drm_gem_object *obj,
}
*iova = vma->iova;
+
+ mutex_unlock(&msm_obj->lock);
return 0;
fail:
del_vma(vma);
- return ret;
-}
-
-/* get iova, taking a reference. Should have a matching put */
-int msm_gem_get_iova(struct drm_gem_object *obj,
- struct msm_gem_address_space *aspace, uint64_t *iova)
-{
- int ret;
-
- mutex_lock(&obj->dev->struct_mutex);
- ret = msm_gem_get_iova_locked(obj, aspace, iova);
- mutex_unlock(&obj->dev->struct_mutex);
-
+ mutex_unlock(&msm_obj->lock);
return ret;
}
@@ -404,11 +416,12 @@ int msm_gem_get_iova(struct drm_gem_object *obj,
uint64_t msm_gem_iova(struct drm_gem_object *obj,
struct msm_gem_address_space *aspace)
{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
struct msm_gem_vma *vma;
- mutex_lock(&obj->dev->struct_mutex);
+ mutex_lock(&msm_obj->lock);
vma = lookup_vma(obj, aspace);
- mutex_unlock(&obj->dev->struct_mutex);
+ mutex_unlock(&msm_obj->lock);
WARN_ON(!vma);
return vma ? vma->iova : 0;
@@ -455,45 +468,57 @@ fail:
return ret;
}
-void *msm_gem_get_vaddr_locked(struct drm_gem_object *obj)
+void *msm_gem_get_vaddr(struct drm_gem_object *obj)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
- WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+ int ret = 0;
+
+ mutex_lock(&msm_obj->lock);
+
+ if (WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED)) {
+ mutex_unlock(&msm_obj->lock);
+ return ERR_PTR(-EBUSY);
+ }
+
+ /* increment vmap_count *before* vmap() call, so shrinker can
+ * check vmap_count (is_vunmapable()) outside of msm_obj->lock.
+ * This guarantees that we won't try to msm_gem_vunmap() this
+ * same object from within the vmap() call (while we already
+ * hold msm_obj->lock)
+ */
+ msm_obj->vmap_count++;
+
if (!msm_obj->vaddr) {
struct page **pages = get_pages(obj);
- if (IS_ERR(pages))
- return ERR_CAST(pages);
+ if (IS_ERR(pages)) {
+ ret = PTR_ERR(pages);
+ goto fail;
+ }
msm_obj->vaddr = vmap(pages, obj->size >> PAGE_SHIFT,
VM_MAP, pgprot_writecombine(PAGE_KERNEL));
- if (msm_obj->vaddr == NULL)
- return ERR_PTR(-ENOMEM);
+ if (msm_obj->vaddr == NULL) {
+ ret = -ENOMEM;
+ goto fail;
+ }
}
- msm_obj->vmap_count++;
+
+ mutex_unlock(&msm_obj->lock);
return msm_obj->vaddr;
-}
-void *msm_gem_get_vaddr(struct drm_gem_object *obj)
-{
- void *ret;
- mutex_lock(&obj->dev->struct_mutex);
- ret = msm_gem_get_vaddr_locked(obj);
- mutex_unlock(&obj->dev->struct_mutex);
- return ret;
+fail:
+ msm_obj->vmap_count--;
+ mutex_unlock(&msm_obj->lock);
+ return ERR_PTR(ret);
}
-void msm_gem_put_vaddr_locked(struct drm_gem_object *obj)
+void msm_gem_put_vaddr(struct drm_gem_object *obj)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
- WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+
+ mutex_lock(&msm_obj->lock);
WARN_ON(msm_obj->vmap_count < 1);
msm_obj->vmap_count--;
-}
-
-void msm_gem_put_vaddr(struct drm_gem_object *obj)
-{
- mutex_lock(&obj->dev->struct_mutex);
- msm_gem_put_vaddr_locked(obj);
- mutex_unlock(&obj->dev->struct_mutex);
+ mutex_unlock(&msm_obj->lock);
}
/* Update madvise status, returns true if not purged, else
@@ -503,15 +528,21 @@ int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ mutex_lock(&msm_obj->lock);
+
WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
if (msm_obj->madv != __MSM_MADV_PURGED)
msm_obj->madv = madv;
- return (msm_obj->madv != __MSM_MADV_PURGED);
+ madv = msm_obj->madv;
+
+ mutex_unlock(&msm_obj->lock);
+
+ return (madv != __MSM_MADV_PURGED);
}
-void msm_gem_purge(struct drm_gem_object *obj)
+void msm_gem_purge(struct drm_gem_object *obj, enum msm_gem_lock subclass)
{
struct drm_device *dev = obj->dev;
struct msm_gem_object *msm_obj = to_msm_bo(obj);
@@ -520,9 +551,11 @@ void msm_gem_purge(struct drm_gem_object *obj)
WARN_ON(!is_purgeable(msm_obj));
WARN_ON(obj->import_attach);
+ mutex_lock_nested(&msm_obj->lock, subclass);
+
put_iova(obj);
- msm_gem_vunmap(obj);
+ msm_gem_vunmap_locked(obj);
put_pages(obj);
@@ -540,12 +573,16 @@ void msm_gem_purge(struct drm_gem_object *obj)
invalidate_mapping_pages(file_inode(obj->filp)->i_mapping,
0, (loff_t)-1);
+
+ mutex_unlock(&msm_obj->lock);
}
-void msm_gem_vunmap(struct drm_gem_object *obj)
+static void msm_gem_vunmap_locked(struct drm_gem_object *obj)
{
struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ WARN_ON(!mutex_is_locked(&msm_obj->lock));
+
if (!msm_obj->vaddr || WARN_ON(!is_vunmapable(msm_obj)))
return;
@@ -553,6 +590,15 @@ void msm_gem_vunmap(struct drm_gem_object *obj)
msm_obj->vaddr = NULL;
}
+void msm_gem_vunmap(struct drm_gem_object *obj, enum msm_gem_lock subclass)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+
+ mutex_lock_nested(&msm_obj->lock, subclass);
+ msm_gem_vunmap_locked(obj);
+ mutex_unlock(&msm_obj->lock);
+}
+
/* must be called before _move_to_active().. */
int msm_gem_sync_object(struct drm_gem_object *obj,
struct msm_fence_context *fctx, bool exclusive)
@@ -674,7 +720,7 @@ void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
uint64_t off = drm_vma_node_start(&obj->vma_node);
const char *madv;
- WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+ mutex_lock(&msm_obj->lock);
switch (msm_obj->madv) {
case __MSM_MADV_PURGED:
@@ -715,6 +761,8 @@ void msm_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
if (fence)
describe_fence(fence, "Exclusive", m);
rcu_read_unlock();
+
+ mutex_unlock(&msm_obj->lock);
}
void msm_gem_describe_objects(struct list_head *list, struct seq_file *m)
@@ -747,6 +795,8 @@ void msm_gem_free_object(struct drm_gem_object *obj)
list_del(&msm_obj->mm_list);
+ mutex_lock(&msm_obj->lock);
+
put_iova(obj);
if (obj->import_attach) {
@@ -761,7 +811,7 @@ void msm_gem_free_object(struct drm_gem_object *obj)
drm_prime_gem_destroy(obj, msm_obj->sgt);
} else {
- msm_gem_vunmap(obj);
+ msm_gem_vunmap_locked(obj);
put_pages(obj);
}
@@ -770,6 +820,7 @@ void msm_gem_free_object(struct drm_gem_object *obj)
drm_gem_object_release(obj);
+ mutex_unlock(&msm_obj->lock);
kfree(msm_obj);
}
@@ -780,14 +831,8 @@ int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file,
struct drm_gem_object *obj;
int ret;
- ret = mutex_lock_interruptible(&dev->struct_mutex);
- if (ret)
- return ret;
-
obj = msm_gem_new(dev, size, flags);
- mutex_unlock(&dev->struct_mutex);
-
if (IS_ERR(obj))
return PTR_ERR(obj);
@@ -802,13 +847,12 @@ int msm_gem_new_handle(struct drm_device *dev, struct drm_file *file,
static int msm_gem_new_impl(struct drm_device *dev,
uint32_t size, uint32_t flags,
struct reservation_object *resv,
- struct drm_gem_object **obj)
+ struct drm_gem_object **obj,
+ bool struct_mutex_locked)
{
struct msm_drm_private *priv = dev->dev_private;
struct msm_gem_object *msm_obj;
- WARN_ON(!mutex_is_locked(&dev->struct_mutex));
-
switch (flags & MSM_BO_CACHE_MASK) {
case MSM_BO_UNCACHED:
case MSM_BO_CACHED:
@@ -824,6 +868,8 @@ static int msm_gem_new_impl(struct drm_device *dev,
if (!msm_obj)
return -ENOMEM;
+ mutex_init(&msm_obj->lock);
+
msm_obj->flags = flags;
msm_obj->madv = MSM_MADV_WILLNEED;
@@ -837,23 +883,28 @@ static int msm_gem_new_impl(struct drm_device *dev,
INIT_LIST_HEAD(&msm_obj->submit_entry);
INIT_LIST_HEAD(&msm_obj->vmas);
- list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
+ if (struct_mutex_locked) {
+ WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+ list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
+ } else {
+ mutex_lock(&dev->struct_mutex);
+ list_add_tail(&msm_obj->mm_list, &priv->inactive_list);
+ mutex_unlock(&dev->struct_mutex);
+ }
*obj = &msm_obj->base;
return 0;
}
-struct drm_gem_object *msm_gem_new(struct drm_device *dev,
- uint32_t size, uint32_t flags)
+static struct drm_gem_object *_msm_gem_new(struct drm_device *dev,
+ uint32_t size, uint32_t flags, bool struct_mutex_locked)
{
struct msm_drm_private *priv = dev->dev_private;
struct drm_gem_object *obj = NULL;
bool use_vram = false;
int ret;
- WARN_ON(!mutex_is_locked(&dev->struct_mutex));
-
size = PAGE_ALIGN(size);
if (!iommu_present(&platform_bus_type))
@@ -870,7 +921,7 @@ struct drm_gem_object *msm_gem_new(struct drm_device *dev,
if (size == 0)
return ERR_PTR(-EINVAL);
- ret = msm_gem_new_impl(dev, size, flags, NULL, &obj);
+ ret = msm_gem_new_impl(dev, size, flags, NULL, &obj, struct_mutex_locked);
if (ret)
goto fail;
@@ -904,10 +955,22 @@ struct drm_gem_object *msm_gem_new(struct drm_device *dev,
return obj;
fail:
- drm_gem_object_unreference(obj);
+ drm_gem_object_unreference_unlocked(obj);
return ERR_PTR(ret);
}
+struct drm_gem_object *msm_gem_new_locked(struct drm_device *dev,
+ uint32_t size, uint32_t flags)
+{
+ return _msm_gem_new(dev, size, flags, true);
+}
+
+struct drm_gem_object *msm_gem_new(struct drm_device *dev,
+ uint32_t size, uint32_t flags)
+{
+ return _msm_gem_new(dev, size, flags, false);
+}
+
struct drm_gem_object *msm_gem_import(struct drm_device *dev,
struct dma_buf *dmabuf, struct sg_table *sgt)
{
@@ -924,11 +987,7 @@ struct drm_gem_object *msm_gem_import(struct drm_device *dev,
size = PAGE_ALIGN(dmabuf->size);
- /* Take mutex so we can modify the inactive list in msm_gem_new_impl */
- mutex_lock(&dev->struct_mutex);
- ret = msm_gem_new_impl(dev, size, MSM_BO_WC, dmabuf->resv, &obj);
- mutex_unlock(&dev->struct_mutex);
-
+ ret = msm_gem_new_impl(dev, size, MSM_BO_WC, dmabuf->resv, &obj, false);
if (ret)
goto fail;
@@ -937,17 +996,22 @@ struct drm_gem_object *msm_gem_import(struct drm_device *dev,
npages = size / PAGE_SIZE;
msm_obj = to_msm_bo(obj);
+ mutex_lock(&msm_obj->lock);
msm_obj->sgt = sgt;
msm_obj->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
if (!msm_obj->pages) {
+ mutex_unlock(&msm_obj->lock);
ret = -ENOMEM;
goto fail;
}
ret = drm_prime_sg_to_page_addr_arrays(sgt, msm_obj->pages, NULL, npages);
- if (ret)
+ if (ret) {
+ mutex_unlock(&msm_obj->lock);
goto fail;
+ }
+ mutex_unlock(&msm_obj->lock);
return obj;
fail:
diff --git a/drivers/gpu/drm/msm/msm_gem.h b/drivers/gpu/drm/msm/msm_gem.h
index 112eb63b5908..91c210d2359c 100644
--- a/drivers/gpu/drm/msm/msm_gem.h
+++ b/drivers/gpu/drm/msm/msm_gem.h
@@ -31,6 +31,7 @@ struct msm_gem_address_space {
* and position mm_node->start is in # of pages:
*/
struct drm_mm mm;
+ spinlock_t lock; /* Protects drm_mm node allocation/removal */
struct msm_mmu *mmu;
struct kref kref;
};
@@ -89,6 +90,7 @@ struct msm_gem_object {
* an IOMMU. Also used for stolen/splashscreen buffer.
*/
struct drm_mm_node *vram_node;
+ struct mutex lock; /* Protects resources associated with bo */
};
#define to_msm_bo(x) container_of(x, struct msm_gem_object, base)
@@ -99,6 +101,7 @@ static inline bool is_active(struct msm_gem_object *msm_obj)
static inline bool is_purgeable(struct msm_gem_object *msm_obj)
{
+ WARN_ON(!mutex_is_locked(&msm_obj->base.dev->struct_mutex));
return (msm_obj->madv == MSM_MADV_DONTNEED) && msm_obj->sgt &&
!msm_obj->base.dma_buf && !msm_obj->base.import_attach;
}
@@ -108,6 +111,25 @@ static inline bool is_vunmapable(struct msm_gem_object *msm_obj)
return (msm_obj->vmap_count == 0) && msm_obj->vaddr;
}
+/* The shrinker can be triggered while we hold objA->lock, and need
+ * to grab objB->lock to purge it. Lockdep just sees these as a single
+ * class of lock, so we use subclasses to teach it the difference.
+ *
+ * OBJ_LOCK_NORMAL is implicit (ie. normal mutex_lock() call), and
+ * OBJ_LOCK_SHRINKER is used by shrinker.
+ *
+ * It is *essential* that we never go down paths that could trigger the
+ * shrinker for a purgable object. This is ensured by checking that
+ * msm_obj->madv == MSM_MADV_WILLNEED.
+ */
+enum msm_gem_lock {
+ OBJ_LOCK_NORMAL,
+ OBJ_LOCK_SHRINKER,
+};
+
+void msm_gem_purge(struct drm_gem_object *obj, enum msm_gem_lock subclass);
+void msm_gem_vunmap(struct drm_gem_object *obj, enum msm_gem_lock subclass);
+
/* Created per submit-ioctl, to track bo's and cmdstream bufs, etc,
* associated with the cmdstream submission for synchronization (and
* make it easier to unwind when things go wrong, etc). This only
diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c
index ab1dd020eb04..b72d8e6cd51d 100644
--- a/drivers/gpu/drm/msm/msm_gem_shrinker.c
+++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c
@@ -20,6 +20,18 @@
static bool msm_gem_shrinker_lock(struct drm_device *dev, bool *unlock)
{
+ /* NOTE: we are *closer* to being able to get rid of
+ * mutex_trylock_recursive().. the msm_gem code itself does
+ * not need struct_mutex, although codepaths that can trigger
+ * shrinker are still called in code-paths that hold the
+ * struct_mutex.
+ *
+ * Also, msm_obj->madv is protected by struct_mutex.
+ *
+ * The next step is probably split out a seperate lock for
+ * protecting inactive_list, so that shrinker does not need
+ * struct_mutex.
+ */
switch (mutex_trylock_recursive(&dev->struct_mutex)) {
case MUTEX_TRYLOCK_FAILED:
return false;
@@ -77,7 +89,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc)
if (freed >= sc->nr_to_scan)
break;
if (is_purgeable(msm_obj)) {
- msm_gem_purge(&msm_obj->base);
+ msm_gem_purge(&msm_obj->base, OBJ_LOCK_SHRINKER);
freed += msm_obj->base.size >> PAGE_SHIFT;
}
}
@@ -106,7 +118,7 @@ msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr)
list_for_each_entry(msm_obj, &priv->inactive_list, mm_list) {
if (is_vunmapable(msm_obj)) {
- msm_gem_vunmap(&msm_obj->base);
+ msm_gem_vunmap(&msm_obj->base, OBJ_LOCK_SHRINKER);
/* since we don't know any better, lets bail after a few
* and if necessary the shrinker will be invoked again.
* Seems better than unmapping *everything*
diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
index c8d01df993da..179cfc60b6ca 100644
--- a/drivers/gpu/drm/msm/msm_gem_submit.c
+++ b/drivers/gpu/drm/msm/msm_gem_submit.c
@@ -245,7 +245,7 @@ static int submit_pin_objects(struct msm_gem_submit *submit)
uint64_t iova;
/* if locking succeeded, pin bo: */
- ret = msm_gem_get_iova_locked(&msm_obj->base,
+ ret = msm_gem_get_iova(&msm_obj->base,
submit->gpu->aspace, &iova);
if (ret)
@@ -301,7 +301,7 @@ static int submit_reloc(struct msm_gem_submit *submit, struct msm_gem_object *ob
/* For now, just map the entire thing. Eventually we probably
* to do it page-by-page, w/ kmap() if not vmap()d..
*/
- ptr = msm_gem_get_vaddr_locked(&obj->base);
+ ptr = msm_gem_get_vaddr(&obj->base);
if (IS_ERR(ptr)) {
ret = PTR_ERR(ptr);
@@ -359,7 +359,7 @@ static int submit_reloc(struct msm_gem_submit *submit, struct msm_gem_object *ob
}
out:
- msm_gem_put_vaddr_locked(&obj->base);
+ msm_gem_put_vaddr(&obj->base);
return ret;
}
diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c
index f285d7e210db..c36321bc8714 100644
--- a/drivers/gpu/drm/msm/msm_gem_vma.c
+++ b/drivers/gpu/drm/msm/msm_gem_vma.c
@@ -50,7 +50,9 @@ msm_gem_unmap_vma(struct msm_gem_address_space *aspace,
aspace->mmu->funcs->unmap(aspace->mmu, vma->iova, sgt, size);
}
+ spin_lock(&aspace->lock);
drm_mm_remove_node(&vma->node);
+ spin_unlock(&aspace->lock);
vma->iova = 0;
@@ -63,10 +65,15 @@ msm_gem_map_vma(struct msm_gem_address_space *aspace,
{
int ret;
- if (WARN_ON(drm_mm_node_allocated(&vma->node)))
+ spin_lock(&aspace->lock);
+ if (WARN_ON(drm_mm_node_allocated(&vma->node))) {
+ spin_unlock(&aspace->lock);
return 0;
+ }
ret = drm_mm_insert_node(&aspace->mm, &vma->node, npages);
+ spin_unlock(&aspace->lock);
+
if (ret)
return ret;
@@ -94,6 +101,7 @@ msm_gem_address_space_create(struct device *dev, struct iommu_domain *domain,
if (!aspace)
return ERR_PTR(-ENOMEM);
+ spin_lock_init(&aspace->lock);
aspace->name = name;
aspace->mmu = msm_iommu_new(dev, domain);
diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index 2d5c9afbcdbe..9f3dbc236ab3 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -497,7 +497,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit,
/* submit takes a reference to the bo and iova until retired: */
drm_gem_object_reference(&msm_obj->base);
- msm_gem_get_iova_locked(&msm_obj->base,
+ msm_gem_get_iova(&msm_obj->base,
submit->gpu->aspace, &iova);
if (submit->bos[i].flags & MSM_SUBMIT_BO_WRITE)
@@ -661,9 +661,7 @@ int msm_gpu_init(struct drm_device *drm, struct platform_device *pdev,
}
/* Create ringbuffer: */
- mutex_lock(&drm->struct_mutex);
gpu->rb = msm_ringbuffer_new(gpu, config->ringsz);
- mutex_unlock(&drm->struct_mutex);
if (IS_ERR(gpu->rb)) {
ret = PTR_ERR(gpu->rb);
gpu->rb = NULL;
diff --git a/drivers/gpu/drm/msm/msm_rd.c b/drivers/gpu/drm/msm/msm_rd.c
index 0e81faab2c50..0366b8092f97 100644
--- a/drivers/gpu/drm/msm/msm_rd.c
+++ b/drivers/gpu/drm/msm/msm_rd.c
@@ -268,7 +268,7 @@ static void snapshot_buf(struct msm_rd_state *rd,
struct msm_gem_object *obj = submit->bos[idx].obj;
const char *buf;
- buf = msm_gem_get_vaddr_locked(&obj->base);
+ buf = msm_gem_get_vaddr(&obj->base);
if (IS_ERR(buf))
return;
@@ -283,7 +283,7 @@ static void snapshot_buf(struct msm_rd_state *rd,
(uint32_t[3]){ iova, size, iova >> 32 }, 12);
rd_write_section(rd, RD_BUFFER_CONTENTS, buf, size);
- msm_gem_put_vaddr_locked(&obj->base);
+ msm_gem_put_vaddr(&obj->base);
}
/* called under struct_mutex */
diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c
index 67b34e069abf..791bca3c6a9c 100644
--- a/drivers/gpu/drm/msm/msm_ringbuffer.c
+++ b/drivers/gpu/drm/msm/msm_ringbuffer.c
@@ -40,7 +40,7 @@ struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int size)
goto fail;
}
- ring->start = msm_gem_get_vaddr_locked(ring->bo);
+ ring->start = msm_gem_get_vaddr(ring->bo);
if (IS_ERR(ring->start)) {
ret = PTR_ERR(ring->start);
goto fail;