On Tue, May 22, 2018 at 11:43 PM, 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() returns err which driver mapped into VM_FAULT_* type. Also return value of vm_insert_mixed() not handled correctly and 0 was returned inside fault_2d() as default. The new function vmf_insert_mixed() will replace this inefficiency by returning correct VM_FAULT_* type.
vmf_error() is the newly introduce inline function in 4.17-rc6.
Signed-off-by: Souptick Joarder jrdr.linux@gmail.com Reviewed-by: Matthew Wilcox mawilcox@microsoft.com
v2: Fixed kbuild error by initialized ret in fault_2d().
drivers/gpu/drm/omapdrm/omap_gem.c | 51 +++++++++++++++++--------------------- drivers/gpu/drm/omapdrm/omap_gem.h | 3 ++- 2 files changed, 25 insertions(+), 29 deletions(-)
diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c index 0faf042..99e4300 100644 --- a/drivers/gpu/drm/omapdrm/omap_gem.c +++ b/drivers/gpu/drm/omapdrm/omap_gem.c @@ -371,7 +371,7 @@ size_t omap_gem_mmap_size(struct drm_gem_object *obj) */
/* Normal handling for the case of faulting in non-tiled buffers */ -static int fault_1d(struct drm_gem_object *obj, +static vm_fault_t fault_1d(struct drm_gem_object *obj, struct vm_area_struct *vma, struct vm_fault *vmf) { struct omap_gem_object *omap_obj = to_omap_bo(obj); @@ -392,11 +392,12 @@ static int fault_1d(struct drm_gem_object *obj, VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address, pfn, pfn << PAGE_SHIFT);
return vm_insert_mixed(vma, vmf->address, __pfn_to_pfn_t(pfn, PFN_DEV));
return vmf_insert_mixed(vma, vmf->address,__pfn_to_pfn_t(pfn, PFN_DEV));}
/* Special handling for the case of faulting in 2d tiled buffers */ -static int fault_2d(struct drm_gem_object *obj, +static vm_fault_t fault_2d(struct drm_gem_object *obj, struct vm_area_struct *vma, struct vm_fault *vmf) { struct omap_gem_object *omap_obj = to_omap_bo(obj); @@ -407,7 +408,8 @@ static int fault_2d(struct drm_gem_object *obj, unsigned long pfn; pgoff_t pgoff, base_pgoff; unsigned long vaddr;
int i, ret, slots;
int i, err, slots;vm_fault_t ret = VM_FAULT_NOPAGE; /* * Note the height of the slot is also equal to the number of pages@@ -473,9 +475,10 @@ static int fault_2d(struct drm_gem_object *obj, memset(pages + slots, 0, sizeof(struct page *) * (n - slots));
ret = tiler_pin(entry->block, pages, ARRAY_SIZE(pages), 0, true);if (ret) {dev_err(obj->dev->dev, "failed to pin: %d\n", ret);
err = tiler_pin(entry->block, pages, ARRAY_SIZE(pages), 0, true);if (err) {ret = vmf_error(err);dev_err(obj->dev->dev, "failed to pin: %d\n", err); return ret; }@@ -485,7 +488,10 @@ static int fault_2d(struct drm_gem_object *obj, pfn, pfn << PAGE_SHIFT);
for (i = n; i > 0; i--) {
vm_insert_mixed(vma, vaddr, __pfn_to_pfn_t(pfn, PFN_DEV));
ret = vmf_insert_mixed(vma,vaddr, __pfn_to_pfn_t(pfn, PFN_DEV));if (ret & VM_FAULT_ERROR)break; pfn += priv->usergart[fmt].stride_pfn; vaddr += PAGE_SIZE * m; }@@ -494,7 +500,7 @@ static int fault_2d(struct drm_gem_object *obj, priv->usergart[fmt].last = (priv->usergart[fmt].last + 1) % NUM_USERGART_ENTRIES;
return 0;
return ret;}
/** @@ -509,14 +515,15 @@ static int fault_2d(struct drm_gem_object *obj,
- vma->vm_private_data points to the GEM object that is backing this
- mapping.
*/ -int omap_gem_fault(struct vm_fault *vmf) +vm_fault_t omap_gem_fault(struct vm_fault *vmf) { struct vm_area_struct *vma = vmf->vma; struct drm_gem_object *obj = vma->vm_private_data; struct omap_gem_object *omap_obj = to_omap_bo(obj); struct drm_device *dev = obj->dev; struct page **pages;
int ret;
int err;vm_fault_t ret; /* Make sure we don't parallel update on a fault, nor move or remove * something from beneath our feet@@ -524,9 +531,11 @@ int omap_gem_fault(struct vm_fault *vmf) mutex_lock(&dev->struct_mutex);
/* if a shmem backed object, make sure we have pages attached now */
ret = get_pages(obj, &pages);if (ret)
err = get_pages(obj, &pages);if (err) {ret = vmf_error(err); goto fail;} /* where should we do corresponding put_pages().. we are mapping * the original page, rather than thru a GART, so we can't rely@@ -542,21 +551,7 @@ int omap_gem_fault(struct vm_fault *vmf)
fail: mutex_unlock(&dev->struct_mutex);
switch (ret) {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 ret;}
/** We override mainly to fix up some of the vm mapping flags.. */ diff --git a/drivers/gpu/drm/omapdrm/omap_gem.h b/drivers/gpu/drm/omapdrm/omap_gem.h index a78bde0..c1c45fb 100644 --- a/drivers/gpu/drm/omapdrm/omap_gem.h +++ b/drivers/gpu/drm/omapdrm/omap_gem.h @@ -21,6 +21,7 @@ #define __OMAPDRM_GEM_H__
#include <linux/types.h> +#include <linux/mm_types.h>
enum dma_data_direction;
@@ -80,7 +81,7 @@ struct dma_buf *omap_gem_prime_export(struct drm_device *dev, struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev, struct dma_buf *buffer);
-int omap_gem_fault(struct vm_fault *vmf); +vm_fault_t omap_gem_fault(struct vm_fault *vmf); int omap_gem_roll(struct drm_gem_object *obj, u32 roll); void omap_gem_cpu_sync_page(struct drm_gem_object *obj, int pgoff); void omap_gem_dma_sync_buffer(struct drm_gem_object *obj, -- 1.9.1
Any comment for this patch ? We would like to get this patch in queue for 4.18.