git.maemo.org Git - kernel-power/blob - kernel-power-2.6.28/debian/patches/support-non-page-aligned-buffers-in-iommu_vmap.diff

   1 --- a/arch/arm/plat-omap/iovmm.c        2011-11-15 06:09:03.909034496 -0500
   2 +++ b/arch/arm/plat-omap/iovmm.c        2011-12-21 14:03:23.673780000 -0500
   3 @@ -59,6 +59,15 @@
   4
   5  static struct kmem_cache *iovm_area_cachep;
   6
   7 +/* return the offset of the first scatterlist entry in a sg table */
   8 +static unsigned int sgtable_offset(const struct sg_table *sgt)
   9 +{
  10 +       if (!sgt || !sgt->nents)
  11 +               return 0;
  12 +
  13 +       return sgt->sgl->offset;
  14 +}
  15 +
  16  /* return total bytes of sg buffers */
  17  static size_t sgtable_len(const struct sg_table *sgt)
  18  {
  19 @@ -71,11 +80,17 @@
  20         for_each_sg(sgt->sgl, sg, sgt->nents, i) {
  21                 size_t bytes;
  22
  23 -               bytes = sg_dma_len(sg);
  24 +               bytes = sg_dma_len(sg) + sg->offset;
  25
  26                 if (!iopgsz_ok(bytes)) {
  27 -                       pr_err("%s: sg[%d] not iommu pagesize(%x)\n",
  28 -                              __func__, i, bytes);
  29 +                       pr_err("%s: sg[%d] not iommu pagesize(%u %u)\n",
  30 +                              __func__, i, bytes, sg->offset);
  31 +                       return 0;
  32 +               }
  33 +
  34 +               if (i && sg->offset) {
  35 +                       pr_err("%s: sg[%d] offset not allowed in internal "
  36 +                              "entries\n", __func__, i);
  37                         return 0;
  38                 }
  39
  40 @@ -112,6 +127,16 @@
  41
  42         return nr_entries;
  43  }
  44 +static struct scatterlist *sg_alloc(unsigned int nents, gfp_t gfp_mask)
  45 +{
  46 +       return kmalloc(nents * sizeof(struct scatterlist), gfp_mask);
  47 +}
  48 +
  49 +static void sg_free(struct scatterlist *sg, unsigned int nents)
  50 +{
  51 +       kfree(sg);
  52 +}
  53 +
  54
  55  /* allocate and initialize sg_table header(a kind of 'superblock') */
  56  static struct sg_table *sgtable_alloc(const size_t bytes, u32 flags)
  57 @@ -138,7 +163,7 @@
  58         if (!sgt)
  59                 return ERR_PTR(-ENOMEM);
  60
  61 -       err = sg_alloc_table(sgt, nr_entries, GFP_KERNEL);
  62 +       err = __sg_alloc_table(sgt, nr_entries, -1, GFP_KERNEL, sg_alloc);
  63         if (err)
  64                 return ERR_PTR(err);
  65
  66 @@ -153,7 +178,7 @@
  67         if (!sgt)
  68                 return;
  69
  70 -       sg_free_table(sgt);
  71 +       __sg_free_table(sgt, -1, sg_free);
  72         kfree(sgt);
  73
  74         pr_debug("%s: sgt:%p\n", __func__, sgt);
  75 @@ -182,8 +207,8 @@
  76                 u32 pa;
  77                 int err;
  78
  79 -               pa = sg_phys(sg);
  80 -               bytes = sg_dma_len(sg);
  81 +               pa = sg_phys(sg) - sg->offset;
  82 +               bytes = sg_dma_len(sg) + sg->offset;
  83
  84                 BUG_ON(bytes != PAGE_SIZE);
  85
  86 @@ -450,8 +475,8 @@
  87                 size_t bytes;
  88                 struct iotlb_entry e;
  89
  90 -               pa = sg_phys(sg);
  91 -               bytes = sg_dma_len(sg);
  92 +               pa = sg_phys(sg) - sg->offset;
  93 +               bytes = sg_dma_len(sg) + sg->offset;
  94
  95                 flags &= ~IOVMF_PGSZ_MASK;
  96                 pgsz = bytes_to_iopgsz(bytes);
  97 @@ -632,7 +657,7 @@
  98         if (IS_ERR_VALUE(da))
  99                 vunmap_sg(va);
 100
 101 -       return da;
 102 +       return da + sgtable_offset(sgt);
 103  }
 104  EXPORT_SYMBOL_GPL(iommu_vmap);
 105
 106 @@ -651,6 +676,7 @@
 107          * 'sgt' is allocated before 'iommu_vmalloc()' is called.
 108          * Just returns 'sgt' to the caller to free
 109          */
 110 +       da &= PAGE_MASK;
 111         sgt = unmap_vm_area(obj, da, vunmap_sg, IOVMF_DISCONT | IOVMF_MMIO);
 112         if (!sgt)
 113                 dev_dbg(obj->dev, "%s: No sgt\n", __func__);