Am 31.05.2018 um 07:07 schrieb Souptick Joarder:

On Thu, May 24, 2018 at 12:25 AM, Souptick Joarder jrdr.linux@gmail.com wrote:

...

Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type.

Ref-> commit 1c8f422059ae ("mm: change return type to vm_fault_t")

Previously vm_insert_{mixed,pfn} returns err which driver mapped into VM_FAULT_* type. The new function vmf_insert_{mixed,pfn} will replace this inefficiency by returning VM_FAULT_* type.

Signed-off-by: Souptick Joarder jrdr.linux@gmail.com

drivers/gpu/drm/ttm/ttm_bo_vm.c | 45 ++++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c index 8eba95b..2d13f03 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c @@ -43,10 +43,11 @@

#define TTM_BO_VM_NUM_PREFAULT 16

-static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo, +static vm_fault_t ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo, struct vm_fault *vmf) {

•   int ret = 0;
  

•   int err = 0;
  

•   vm_fault_t ret = 0;
  

Please keep reverse xmas tree order for variable declarations.

Except for that it looks good to me, Christian.

...

     if (likely(!bo->moving))
             goto out_unlock;

@@ -77,9 +78,9 @@ static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo, /* * Ordinary wait. */

•   ret = dma_fence_wait(bo->moving, true);
  

•   if (unlikely(ret != 0)) {
  

•           ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
  

•   err = dma_fence_wait(bo->moving, true);
  

•   if (unlikely(err != 0)) {
  

•           ret = (err != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
                     VM_FAULT_NOPAGE;
             goto out_unlock;
     }
  

@@ -104,7 +105,7 @@ static unsigned long ttm_bo_io_mem_pfn(struct ttm_buffer_object *bo, + page_offset; }

-static int ttm_bo_vm_fault(struct vm_fault *vmf) +static vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct ttm_buffer_object *bo = (struct ttm_buffer_object *) @@ -115,8 +116,9 @@ static int ttm_bo_vm_fault(struct vm_fault *vmf) unsigned long pfn; struct ttm_tt *ttm = NULL; struct page *page;

•   int ret;
  

•   int err;
     int i;
  

•   vm_fault_t ret = VM_FAULT_NOPAGE;
     unsigned long address = vmf->address;
     struct ttm_mem_type_manager *man =
             &bdev->man[bo->mem.mem_type];
  

@@ -128,9 +130,9 @@ static int ttm_bo_vm_fault(struct vm_fault *vmf) * for reserve, and if it fails, retry the fault after waiting * for the buffer to become unreserved. */

•   ret = ttm_bo_reserve(bo, true, true, NULL);
  

•   if (unlikely(ret != 0)) {
  

•           if (ret != -EBUSY)
  

•   err = ttm_bo_reserve(bo, true, true, NULL);
  

•   if (unlikely(err != 0)) {
  

•           if (err != -EBUSY)
                     return VM_FAULT_NOPAGE;
  
             if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
  

@@ -162,8 +164,8 @@ static int ttm_bo_vm_fault(struct vm_fault *vmf) }

     if (bdev->driver->fault_reserve_notify) {

•           ret = bdev->driver->fault_reserve_notify(bo);
  

•           switch (ret) {
  

•           err = bdev->driver->fault_reserve_notify(bo);
  

•           switch (err) {
             case 0:
                     break;
             case -EBUSY:
  

@@ -191,13 +193,13 @@ static int ttm_bo_vm_fault(struct vm_fault *vmf) goto out_unlock; }

•   ret = ttm_mem_io_lock(man, true);
  

•   if (unlikely(ret != 0)) {
  

•   err = ttm_mem_io_lock(man, true);
  

•   if (unlikely(err != 0)) {
             ret = VM_FAULT_NOPAGE;
             goto out_unlock;
     }
  

•   ret = ttm_mem_io_reserve_vm(bo);
  

•   if (unlikely(ret != 0)) {
  

•   err = ttm_mem_io_reserve_vm(bo);
  

•   if (unlikely(err != 0)) {
             ret = VM_FAULT_SIGBUS;
             goto out_io_unlock;
     }
  

@@ -265,23 +267,20 @@ static int ttm_bo_vm_fault(struct vm_fault *vmf) }

             if (vma->vm_flags & VM_MIXEDMAP)

•                   ret = vm_insert_mixed(&cvma, address,
  

•                   ret = vmf_insert_mixed(&cvma, address,
                                     __pfn_to_pfn_t(pfn, PFN_DEV));
             else
  

•                   ret = vm_insert_pfn(&cvma, address, pfn);
  

•                   ret = vmf_insert_pfn(&cvma, address, pfn);
  
             /*
              * Somebody beat us to this PTE or prefaulting to
              * an already populated PTE, or prefaulting error.
              */
  
  

•           if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
  

•           if (unlikely((ret == VM_FAULT_NOPAGE && i > 0)))
                     break;
  

•           else if (unlikely(ret != 0)) {
  

•                   ret =
  

•                       (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
  

•           else if (unlikely(ret & VM_FAULT_ERROR))
                     goto out_io_unlock;
  

•           }
  
             address += PAGE_SIZE;
             if (unlikely(++page_offset >= page_last))
  

-- 1.9.1

Any comment for this patch ?