hmm_vma_fault is marked as a legacy API to get rid of, but quite suites
the current nouvea flow. Move it to the only user in preparation for
fixing a locking bug involving caller and callee.
Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/gpu/drm/nouveau/nouveau_svm.c | 54 ++++++++++++++++++++++++++-
include/linux/hmm.h | 54 ---------------------------
2 files changed, 53 insertions(+), 55 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c
index 9d40114d7949..e831f4184a17 100644
--- a/drivers/gpu/drm/nouveau/nouveau_svm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
@@ -36,6 +36,13 @@
#include <linux/sort.h>
#include <linux/hmm.h>
+/*
+ * When waiting for mmu notifiers we need some kind of time out otherwise we
+ * could potentialy wait for ever, 1000ms ie 1s sounds like a long time to
+ * wait already.
+ */
+#define NOUVEAU_RANGE_FAULT_TIMEOUT 1000
+
struct nouveau_svm {
struct nouveau_drm *drm;
struct mutex mutex;
@@ -475,6 +482,51 @@ nouveau_svm_fault_cache(struct nouveau_svm *svm,
fault->inst, fault->addr, fault->access);
}
+static int
+nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range,
+ bool block)
+{
+ long ret;
+
+ /*
+ * With the old API the driver must set each individual entries with
+ * the requested flags (valid, write, ...). So here we set the mask to
+ * keep intact the entries provided by the driver and zero out the
+ * default_flags.
+ */
+ range->default_flags = 0;
+ range->pfn_flags_mask = -1UL;
+
+ ret = hmm_range_register(range, mirror,
+ range->start, range->end,
+ PAGE_SHIFT);
+ if (ret)
+ return (int)ret;
+
+ if (!hmm_range_wait_until_valid(range, NOUVEAU_RANGE_FAULT_TIMEOUT)) {
+ /*
+ * The mmap_sem was taken by driver we release it here and
+ * returns -EAGAIN which correspond to mmap_sem have been
+ * drop in the old API.
+ */
+ up_read(&range->vma->vm_mm->mmap_sem);
+ return -EAGAIN;
+ }
+
+ ret = hmm_range_fault(range, block);
+ if (ret <= 0) {
+ if (ret == -EBUSY || !ret) {
+ /* Same as above, drop mmap_sem to match old API. */
+ up_read(&range->vma->vm_mm->mmap_sem);
+ ret = -EBUSY;
+ } else if (ret == -EAGAIN)
+ ret = -EBUSY;
+ hmm_range_unregister(range);
+ return ret;
+ }
+ return 0;
+}
+
static int
nouveau_svm_fault(struct nvif_notify *notify)
{
@@ -649,7 +701,7 @@ nouveau_svm_fault(struct nvif_notify *notify)
range.values = nouveau_svm_pfn_values;
range.pfn_shift = NVIF_VMM_PFNMAP_V0_ADDR_SHIFT;
again:
- ret = hmm_vma_fault(&svmm->mirror, &range, true);
+ ret = nouveau_range_fault(&svmm->mirror, &range, true);
if (ret == 0) {
mutex_lock(&svmm->mutex);
if (!hmm_range_unregister(&range)) {
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index 4b185d286c3b..3457cf9182e5 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -478,60 +478,6 @@ long hmm_range_dma_unmap(struct hmm_range *range,
dma_addr_t *daddrs,
bool dirty);
-/*
- * HMM_RANGE_DEFAULT_TIMEOUT - default timeout (ms) when waiting for a range
- *
- * When waiting for mmu notifiers we need some kind of time out otherwise we
- * could potentialy wait for ever, 1000ms ie 1s sounds like a long time to
- * wait already.
- */
-#define HMM_RANGE_DEFAULT_TIMEOUT 1000
-
-/* This is a temporary helper to avoid merge conflict between trees. */
-static inline int hmm_vma_fault(struct hmm_mirror *mirror,
- struct hmm_range *range, bool block)
-{
- long ret;
-
- /*
- * With the old API the driver must set each individual entries with
- * the requested flags (valid, write, ...). So here we set the mask to
- * keep intact the entries provided by the driver and zero out the
- * default_flags.
- */
- range->default_flags = 0;
- range->pfn_flags_mask = -1UL;
-
- ret = hmm_range_register(range, mirror,
- range->start, range->end,
- PAGE_SHIFT);
- if (ret)
- return (int)ret;
-
- if (!hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT)) {
- /*
- * The mmap_sem was taken by driver we release it here and
- * returns -EAGAIN which correspond to mmap_sem have been
- * drop in the old API.
- */
- up_read(&range->vma->vm_mm->mmap_sem);
- return -EAGAIN;
- }
-
- ret = hmm_range_fault(range, block);
- if (ret <= 0) {
- if (ret == -EBUSY || !ret) {
- /* Same as above, drop mmap_sem to match old API. */
- up_read(&range->vma->vm_mm->mmap_sem);
- ret = -EBUSY;
- } else if (ret == -EAGAIN)
- ret = -EBUSY;
- hmm_range_unregister(range);
- return ret;
- }
- return 0;
-}
-
/* Below are for HMM internal use only! Not to be used by device driver! */
static inline void hmm_mm_init(struct mm_struct *mm)
{
--
2.20.1
On 6/30/19 11:20 PM, Christoph Hellwig wrote:
> hmm_vma_fault is marked as a legacy API to get rid of, but quite suites
> the current nouvea flow. Move it to the only user in preparation for
I didn't quite parse the phrase "quite suites the current nouvea flow."
s/nouvea/nouveau/
> fixing a locking bug involving caller and callee.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
I see where you are going with this and it
looks like straightforward code movement so,
Reviewed-by: Ralph Campbell <[email protected]>
> ---
> drivers/gpu/drm/nouveau/nouveau_svm.c | 54 ++++++++++++++++++++++++++-
> include/linux/hmm.h | 54 ---------------------------
> 2 files changed, 53 insertions(+), 55 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c
> index 9d40114d7949..e831f4184a17 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_svm.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
> @@ -36,6 +36,13 @@
> #include <linux/sort.h>
> #include <linux/hmm.h>
>
> +/*
> + * When waiting for mmu notifiers we need some kind of time out otherwise we
> + * could potentialy wait for ever, 1000ms ie 1s sounds like a long time to
> + * wait already.
> + */
> +#define NOUVEAU_RANGE_FAULT_TIMEOUT 1000
> +
> struct nouveau_svm {
> struct nouveau_drm *drm;
> struct mutex mutex;
> @@ -475,6 +482,51 @@ nouveau_svm_fault_cache(struct nouveau_svm *svm,
> fault->inst, fault->addr, fault->access);
> }
>
> +static int
> +nouveau_range_fault(struct hmm_mirror *mirror, struct hmm_range *range,
> + bool block)
> +{
> + long ret;
> +
> + /*
> + * With the old API the driver must set each individual entries with
> + * the requested flags (valid, write, ...). So here we set the mask to
> + * keep intact the entries provided by the driver and zero out the
> + * default_flags.
> + */
> + range->default_flags = 0;
> + range->pfn_flags_mask = -1UL;
> +
> + ret = hmm_range_register(range, mirror,
> + range->start, range->end,
> + PAGE_SHIFT);
> + if (ret)
> + return (int)ret;
> +
> + if (!hmm_range_wait_until_valid(range, NOUVEAU_RANGE_FAULT_TIMEOUT)) {
> + /*
> + * The mmap_sem was taken by driver we release it here and
> + * returns -EAGAIN which correspond to mmap_sem have been
> + * drop in the old API.
> + */
> + up_read(&range->vma->vm_mm->mmap_sem);
> + return -EAGAIN;
> + }
> +
> + ret = hmm_range_fault(range, block);
> + if (ret <= 0) {
> + if (ret == -EBUSY || !ret) {
> + /* Same as above, drop mmap_sem to match old API. */
> + up_read(&range->vma->vm_mm->mmap_sem);
> + ret = -EBUSY;
> + } else if (ret == -EAGAIN)
> + ret = -EBUSY;
> + hmm_range_unregister(range);
> + return ret;
> + }
> + return 0;
> +}
> +
> static int
> nouveau_svm_fault(struct nvif_notify *notify)
> {
> @@ -649,7 +701,7 @@ nouveau_svm_fault(struct nvif_notify *notify)
> range.values = nouveau_svm_pfn_values;
> range.pfn_shift = NVIF_VMM_PFNMAP_V0_ADDR_SHIFT;
> again:
> - ret = hmm_vma_fault(&svmm->mirror, &range, true);
> + ret = nouveau_range_fault(&svmm->mirror, &range, true);
> if (ret == 0) {
> mutex_lock(&svmm->mutex);
> if (!hmm_range_unregister(&range)) {
> diff --git a/include/linux/hmm.h b/include/linux/hmm.h
> index 4b185d286c3b..3457cf9182e5 100644
> --- a/include/linux/hmm.h
> +++ b/include/linux/hmm.h
> @@ -478,60 +478,6 @@ long hmm_range_dma_unmap(struct hmm_range *range,
> dma_addr_t *daddrs,
> bool dirty);
>
> -/*
> - * HMM_RANGE_DEFAULT_TIMEOUT - default timeout (ms) when waiting for a range
> - *
> - * When waiting for mmu notifiers we need some kind of time out otherwise we
> - * could potentialy wait for ever, 1000ms ie 1s sounds like a long time to
> - * wait already.
> - */
> -#define HMM_RANGE_DEFAULT_TIMEOUT 1000
> -
> -/* This is a temporary helper to avoid merge conflict between trees. */
> -static inline int hmm_vma_fault(struct hmm_mirror *mirror,
> - struct hmm_range *range, bool block)
> -{
> - long ret;
> -
> - /*
> - * With the old API the driver must set each individual entries with
> - * the requested flags (valid, write, ...). So here we set the mask to
> - * keep intact the entries provided by the driver and zero out the
> - * default_flags.
> - */
> - range->default_flags = 0;
> - range->pfn_flags_mask = -1UL;
> -
> - ret = hmm_range_register(range, mirror,
> - range->start, range->end,
> - PAGE_SHIFT);
> - if (ret)
> - return (int)ret;
> -
> - if (!hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT)) {
> - /*
> - * The mmap_sem was taken by driver we release it here and
> - * returns -EAGAIN which correspond to mmap_sem have been
> - * drop in the old API.
> - */
> - up_read(&range->vma->vm_mm->mmap_sem);
> - return -EAGAIN;
> - }
> -
> - ret = hmm_range_fault(range, block);
> - if (ret <= 0) {
> - if (ret == -EBUSY || !ret) {
> - /* Same as above, drop mmap_sem to match old API. */
> - up_read(&range->vma->vm_mm->mmap_sem);
> - ret = -EBUSY;
> - } else if (ret == -EAGAIN)
> - ret = -EBUSY;
> - hmm_range_unregister(range);
> - return ret;
> - }
> - return 0;
> -}
> -
> /* Below are for HMM internal use only! Not to be used by device driver! */
> static inline void hmm_mm_init(struct mm_struct *mm)
> {
>
On Wed, Jul 3, 2019 at 1:49 PM Ralph Campbell <[email protected]> wrote:
> On 6/30/19 11:20 PM, Christoph Hellwig wrote:
> > hmm_vma_fault is marked as a legacy API to get rid of, but quite suites
> > the current nouvea flow. Move it to the only user in preparation for
>
> I didn't quite parse the phrase "quite suites the current nouvea flow."
> s/nouvea/nouveau/
As long as you're fixing typos, suites -> suits.
On Mon, Jul 01, 2019 at 08:20:18AM +0200, Christoph Hellwig wrote:
> hmm_vma_fault is marked as a legacy API to get rid of, but quite suites
> the current nouvea flow. Move it to the only user in preparation for
> fixing a locking bug involving caller and callee.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> drivers/gpu/drm/nouveau/nouveau_svm.c | 54 ++++++++++++++++++++++++++-
> include/linux/hmm.h | 54 ---------------------------
> 2 files changed, 53 insertions(+), 55 deletions(-)
I was thinking about doing exactly this too, but amdgpu started using
this already obsolete API in their latest driver :(
So, we now need to get both drivers to move to the modern API.
Jason
On Wed, Jul 03, 2019 at 03:03:56PM -0300, Jason Gunthorpe wrote:
> I was thinking about doing exactly this too, but amdgpu started using
> this already obsolete API in their latest driver :(
>
> So, we now need to get both drivers to move to the modern API.
Actually the AMD folks fixed this up after we pointed it out to them,
so even in linux-next it just is nouveau that needs fixing.
On Wed, Jul 03, 2019 at 08:05:25PM +0200, Christoph Hellwig wrote:
> On Wed, Jul 03, 2019 at 03:03:56PM -0300, Jason Gunthorpe wrote:
> > I was thinking about doing exactly this too, but amdgpu started using
> > this already obsolete API in their latest driver :(
> >
> > So, we now need to get both drivers to move to the modern API.
>
> Actually the AMD folks fixed this up after we pointed it out to them,
> so even in linux-next it just is nouveau that needs fixing.
Oh, I looked at an older -next, my mistake. Lets do it then.
Jason