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.
see commit 1c8f422059ae ("mm: change return type to vm_fault_t") for reference.
Previously vm_insert_mixed returns err which driver mapped into VM_FAULT_* type. The new function vmf_insert_mixed will replace this inefficiency by returning VM_FAULT_* type.
Signed-off-by: Souptick Joarder jrdr.linux@gmail.com --- drivers/gpu/drm/v3d/v3d_bo.c | 23 +++-------------------- drivers/gpu/drm/v3d/v3d_drv.h | 3 ++- 2 files changed, 5 insertions(+), 21 deletions(-)
diff --git a/drivers/gpu/drm/v3d/v3d_bo.c b/drivers/gpu/drm/v3d/v3d_bo.c index 7b1e2a5..f4e8de4 100644 --- a/drivers/gpu/drm/v3d/v3d_bo.c +++ b/drivers/gpu/drm/v3d/v3d_bo.c @@ -227,37 +227,20 @@ struct reservation_object *v3d_prime_res_obj(struct drm_gem_object *obj) vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); }
-int v3d_gem_fault(struct vm_fault *vmf) +vm_fault_t v3d_gem_fault(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct drm_gem_object *obj = vma->vm_private_data; struct v3d_bo *bo = to_v3d_bo(obj); unsigned long pfn; pgoff_t pgoff; - int ret;
/* We don't use vmf->pgoff since that has the fake offset: */ pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT; pfn = page_to_pfn(bo->pages[pgoff]);
- ret = vm_insert_mixed(vma, vmf->address, __pfn_to_pfn_t(pfn, PFN_DEV)); - - switch (ret) { - case -EAGAIN: - case 0: - case -ERESTARTSYS: - case -EINTR: - case -EBUSY: - /* - * EBUSY is ok: this just means that another thread - * already did the job. - */ - return VM_FAULT_NOPAGE; - case -ENOMEM: - return VM_FAULT_OOM; - default: - return VM_FAULT_SIGBUS; - } + return vmf_insert_mixed(vma, vmf->address, + __pfn_to_pfn_t(pfn, PFN_DEV)); }
int v3d_mmap(struct file *filp, struct vm_area_struct *vma) diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h index a043ac3..09aa634 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.h +++ b/drivers/gpu/drm/v3d/v3d_drv.h @@ -2,6 +2,7 @@ /* Copyright (C) 2015-2018 Broadcom */
#include <linux/reservation.h> +#include <linux/mm_types.h> #include <drm/drmP.h> #include <drm/drm_encoder.h> #include <drm/drm_gem.h> @@ -248,7 +249,7 @@ int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv); int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv); -int v3d_gem_fault(struct vm_fault *vmf); +vm_fault_t v3d_gem_fault(struct vm_fault *vmf); int v3d_mmap(struct file *filp, struct vm_area_struct *vma); struct reservation_object *v3d_prime_res_obj(struct drm_gem_object *obj); int v3d_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma);
On Tue, Jul 03, 2018 at 09:40:43PM +0530, Souptick Joarder 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.
see commit 1c8f422059ae ("mm: change return type to vm_fault_t") for reference.
Previously vm_insert_mixed returns err which driver mapped into VM_FAULT_* type. The new function vmf_insert_mixed will replace this inefficiency by returning VM_FAULT_* type.
I really think this changelog could do with more work. Specifically for this patch, I'd just say:
Convert v3d_gem_fault to return vm_fault_t
Instead of converting an errno into a vm_fault_t ourselves, use vmf_insert_mixed() which returns a vm_fault_t directly.
unsigned long pfn; pgoff_t pgoff;
int ret;
/* We don't use vmf->pgoff since that has the fake offset: */ pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT; pfn = page_to_pfn(bo->pages[pgoff]);
ret = vm_insert_mixed(vma, vmf->address, __pfn_to_pfn_t(pfn, PFN_DEV));
switch (ret) {
case -EAGAIN:
case 0:
case -ERESTARTSYS:
case -EINTR:
case -EBUSY:
/** EBUSY is ok: this just means that another thread* already did the job.*/return VM_FAULT_NOPAGE;case -ENOMEM:
return VM_FAULT_OOM;default:
return VM_FAULT_SIGBUS;}
- return vmf_insert_mixed(vma, vmf->address,
__pfn_to_pfn_t(pfn, PFN_DEV));}
The line-split here is kind of ugly. I'd do a little more extensive surgery:
- unsigned long pfn; + pfn_t pfn;
- pfn = page_to_pfn(bo->pages[pgoff]); + pfn = __pfn_to_pfn_t(page_to_pfn(bo->pages[pgoff]), PFN_DEV);
+ return vmf_insert_mixed(vma, vmf->address, pfn);
On 03-Jul-2018 11:12 PM, "Matthew Wilcox" willy@infradead.org wrote:
On Tue, Jul 03, 2018 at 09:40:43PM +0530, Souptick Joarder 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.
see commit 1c8f422059ae ("mm: change return type to vm_fault_t") for reference.
Previously vm_insert_mixed returns err which driver mapped into VM_FAULT_* type. The new function vmf_insert_mixed will replace this inefficiency by returning VM_FAULT_* type.
I really think this changelog could do with more work. Specifically for this patch, I'd just say:
Convert v3d_gem_fault to return vm_fault_t
Instead of converting an errno into a vm_fault_t ourselves, use vmf_insert_mixed() which returns a vm_fault_t directly.
unsigned long pfn; pgoff_t pgoff;
int ret; /* We don't use vmf->pgoff since that has the fake offset: */ pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT; pfn = page_to_pfn(bo->pages[pgoff]);ret = vm_insert_mixed(vma, vmf->address, __pfn_to_pfn_t(pfn,
PFN_DEV));
switch (ret) {case -EAGAIN:case 0:case -ERESTARTSYS:case -EINTR:case -EBUSY:/** EBUSY is ok: this just means that another thread* already did the job.*/return VM_FAULT_NOPAGE;case -ENOMEM:return VM_FAULT_OOM;default:return VM_FAULT_SIGBUS;}
return vmf_insert_mixed(vma, vmf->address,__pfn_to_pfn_t(pfn, PFN_DEV));}
The line-split here is kind of ugly. I'd do a little more extensive
surgery:
unsigned long pfn;
pfn_t pfn;
pfn = page_to_pfn(bo->pages[pgoff]);
pfn = __pfn_to_pfn_t(page_to_pfn(bo->pages[pgoff]), PFN_DEV);return vmf_insert_mixed(vma, vmf->address, pfn);
Ok, I will add the same and send v2.
dri-devel@lists.freedesktop.org
-
Matthew Wilcox -
Souptick Joarder