diff --git a/arch/x86_64/kernel/pci-gart.c b/arch/x86_64/kernel/pci-gart.c index 8bc2ed7..48ce635 100644 --- a/arch/x86_64/kernel/pci-gart.c +++ b/arch/x86_64/kernel/pci-gart.c @@ -319,27 +319,23 @@ static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg, } /* Map multiple scatterlist entries continuous into the first. */ -static int __dma_map_cont(struct scatterlist *sg, int start, int stopat, +static int __dma_map_cont(struct scatterlist *start, int nelems, struct scatterlist *sout, unsigned long pages) { unsigned long iommu_start = alloc_iommu(pages); unsigned long iommu_page = iommu_start; struct scatterlist *s; - int i, nelems; + int i; if (iommu_start == -1) return -1; - nelems = stopat - start; - while (start--) - sg = sg_next(sg); - - for_each_sg(sg, s, nelems, i) { + for_each_sg(start, s, nelems, i) { unsigned long pages, addr; unsigned long phys_addr = s->dma_address; - BUG_ON(i > start && s->offset); - if (i == start) { + BUG_ON(s != start && s->offset); + if (s == start) { *sout = *s; sout->dma_address = iommu_bus_base; sout->dma_address += iommu_page*PAGE_SIZE + s->offset; @@ -361,19 +357,17 @@ static int __dma_map_cont(struct scatterlist *sg, int start, int stopat, return 0; } -static inline int dma_map_cont(struct scatterlist *sg, int start, int stopat, +static inline int dma_map_cont(struct scatterlist *start, int nelems, struct scatterlist *sout, unsigned long pages, int need) { if (!need) { - BUG_ON(stopat - start != 1); - while (--start) - sg = sg_next(sg); - *sout = *sg; - sout->dma_length = sg->length; + BUG_ON(nelems != 1); + *sout = *start; + sout->dma_length = start->length; return 0; } - return __dma_map_cont(sg, start, stopat, sout, pages); + return __dma_map_cont(start, nelems, sout, pages); } /* @@ -387,7 +381,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir) int start; unsigned long pages = 0; int need = 0, nextneed; - struct scatterlist *s, *ps; + struct scatterlist *s, *ps, *start_sg; if (nents == 0) return 0; @@ -397,6 +391,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir) out = 0; start = 0; + start_sg = sg; ps = NULL; /* shut up gcc */ for_each_sg(sg, s, nents, i) { dma_addr_t addr = page_to_phys(s->page) + s->offset; @@ -411,12 +406,13 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir) boundary and the new one doesn't have an offset. */ if (!iommu_merge || !nextneed || !need || s->offset || (ps->offset + ps->length) % PAGE_SIZE) { - if (dma_map_cont(sg, start, i, sg+out, pages, - need) < 0) + if (dma_map_cont(start_sg, i - start, sg+out, + pages, need) < 0) goto error; out++; pages = 0; - start = i; + start = i; + start_sg = s; } } @@ -424,7 +420,7 @@ int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir) pages += to_pages(s->offset, s->length); ps = s; } - if (dma_map_cont(sg, start, i, sg+out, pages, need) < 0) + if (dma_map_cont(start_sg, i - start, sg+out, pages, need) < 0) goto error; out++; flush_gart();