diff --git a/drivers/gpu/drm/i915/i915_mm.c b/drivers/gpu/drm/i915/i915_mm.c index 4c8cd08c672d..9a777b0ff59b 100644 --- a/drivers/gpu/drm/i915/i915_mm.c +++ b/drivers/gpu/drm/i915/i915_mm.c @@ -28,10 +28,46 @@ #include "i915_drv.h" -#define EXPECTED_FLAGS (VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP) +struct remap_pfn { + struct mm_struct *mm; + unsigned long pfn; + pgprot_t prot; + + struct sgt_iter sgt; + resource_size_t iobase; +}; #define use_dma(io) ((io) != -1) +static inline unsigned long sgt_pfn(const struct remap_pfn *r) +{ + if (use_dma(r->iobase)) + return (r->sgt.dma + r->sgt.curr + r->iobase) >> PAGE_SHIFT; + else + return r->sgt.pfn + (r->sgt.curr >> PAGE_SHIFT); +} + +static int remap_sg(pte_t *pte, unsigned long addr, void *data) +{ + struct remap_pfn *r = data; + + if (GEM_WARN_ON(!r->sgt.sgp)) + return -EINVAL; + + /* Special PTE are not associated with any struct page */ + set_pte_at(r->mm, addr, pte, + pte_mkspecial(pfn_pte(sgt_pfn(r), r->prot))); + r->pfn++; /* track insertions in case we need to unwind later */ + + r->sgt.curr += PAGE_SIZE; + if (r->sgt.curr >= r->sgt.max) + r->sgt = __sgt_iter(__sg_next(r->sgt.sgp), use_dma(r->iobase)); + + return 0; +} + +#define EXPECTED_FLAGS (VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP) + /** * remap_io_sg - remap an IO mapping to userspace * @vma: user vma to map to @@ -46,7 +82,12 @@ int remap_io_sg(struct vm_area_struct *vma, unsigned long addr, unsigned long size, struct scatterlist *sgl, resource_size_t iobase) { - unsigned long pfn, len, remapped = 0; + struct remap_pfn r = { + .mm = vma->vm_mm, + .prot = vma->vm_page_prot, + .sgt = __sgt_iter(sgl, use_dma(iobase)), + .iobase = iobase, + }; int err; /* We rely on prevalidation of the io-mapping to skip track_pfn(). */ @@ -55,25 +96,11 @@ int remap_io_sg(struct vm_area_struct *vma, if (!use_dma(iobase)) flush_cache_range(vma, addr, size); - do { - if (use_dma(iobase)) { - if (!sg_dma_len(sgl)) - break; - pfn = (sg_dma_address(sgl) + iobase) >> PAGE_SHIFT; - len = sg_dma_len(sgl); - } else { - pfn = page_to_pfn(sg_page(sgl)); - len = sgl->length; - } + err = apply_to_page_range(r.mm, addr, size, remap_sg, &r); + if (unlikely(err)) { + zap_vma_ptes(vma, addr, r.pfn << PAGE_SHIFT); + return err; + } - err = remap_pfn_range(vma, addr + remapped, pfn, len, - vma->vm_page_prot); - if (err) - break; - remapped += len; - } while ((sgl = __sg_next(sgl))); - - if (err) - zap_vma_ptes(vma, addr, remapped); - return err; + return 0; }