lkml.org 
[lkml]   [2010]   [Oct]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [PATCHv2 2/3] iovmm: add superpages support to fixed da address
    From
    On Tue, Oct 5, 2010 at 12:02 AM, Fernando Guzman Lugo <x0095840@ti.com> wrote:
    > This patch adds superpages support to fixed ad address
    > inside iommu_kmap function.
    >
    > Signed-off-by: Fernando Guzman Lugo <x0095840@ti.com>
    > ---
    >  arch/arm/plat-omap/iovmm.c |   61 ++++++++++++++++++++++++++-----------------
    >  1 files changed, 37 insertions(+), 24 deletions(-)
    >
    > diff --git a/arch/arm/plat-omap/iovmm.c b/arch/arm/plat-omap/iovmm.c
    > index 34f0012..8006a19 100644
    > --- a/arch/arm/plat-omap/iovmm.c
    > +++ b/arch/arm/plat-omap/iovmm.c
    > @@ -87,27 +87,37 @@ static size_t sgtable_len(const struct sg_table *sgt)
    >  }
    >  #define sgtable_ok(x)  (!!sgtable_len(x))
    >
    > +
    > +static unsigned max_alignment(u32 addr)
    > +{
    > +       int i;
    > +       unsigned pagesize[] = { SZ_16M, SZ_1M, SZ_64K, SZ_4K, };
    > +       for (i = 0; i < ARRAY_SIZE(pagesize) && addr & (pagesize[i] - 1); i++)
    > +               ;
    > +       return (i < ARRAY_SIZE(pagesize)) ? pagesize[i] : 0;
    > +}
    > +
    > +

    I don't think those extra spaces make sense.

    >  /*
    >  * calculate the optimal number sg elements from total bytes based on
    >  * iommu superpages
    >  */
    > -static unsigned int sgtable_nents(size_t bytes)
    > +static unsigned int sgtable_nents(size_t bytes, u32 da, u32 pa)
    >  {
    > -       int i;
    > -       unsigned int nr_entries;
    > -       const unsigned long pagesize[] = { SZ_16M, SZ_1M, SZ_64K, SZ_4K, };
    > +       unsigned int nr_entries = 0, ent_sz;

    How about s/unsigned int/unsigned/?

    >
    >        if (!IS_ALIGNED(bytes, PAGE_SIZE)) {
    >                pr_err("%s: wrong size %08x\n", __func__, bytes);
    >                return 0;
    >        }
    >
    > -       nr_entries = 0;
    > -       for (i = 0; i < ARRAY_SIZE(pagesize); i++) {
    > -               if (bytes >= pagesize[i]) {
    > -                       nr_entries += (bytes / pagesize[i]);
    > -                       bytes %= pagesize[i];
    > -               }
    > +       while (bytes) {
    > +               ent_sz = max_alignment(da | pa);
    > +               ent_sz = min(ent_sz, (unsigned)iopgsz_max(bytes));
    > +               nr_entries++;
    > +               da += ent_sz;
    > +               pa += ent_sz;
    > +               bytes -= ent_sz;
    >        }
    >        BUG_ON(bytes);
    >
    > @@ -115,7 +125,8 @@ static unsigned int sgtable_nents(size_t bytes)
    >  }
    >
    >  /* allocate and initialize sg_table header(a kind of 'superblock') */
    > -static struct sg_table *sgtable_alloc(const size_t bytes, u32 flags)
    > +static struct sg_table *sgtable_alloc(const size_t bytes, u32 flags,
    > +                                                       u32 da, u32 pa)
    >  {
    >        unsigned int nr_entries;
    >        int err;
    > @@ -127,9 +138,8 @@ static struct sg_table *sgtable_alloc(const size_t bytes, u32 flags)
    >        if (!IS_ALIGNED(bytes, PAGE_SIZE))
    >                return ERR_PTR(-EINVAL);
    >
    > -       /* FIXME: IOVMF_DA_FIXED should support 'superpages' */
    > -       if ((flags & IOVMF_LINEAR) && (flags & IOVMF_DA_ANON)) {
    > -               nr_entries = sgtable_nents(bytes);
    > +       if (flags & IOVMF_LINEAR) {
    > +               nr_entries = sgtable_nents(bytes, da, pa);
    >                if (!nr_entries)
    >                        return ERR_PTR(-EINVAL);
    >        } else
    > @@ -409,7 +419,8 @@ static inline void sgtable_drain_vmalloc(struct sg_table *sgt)
    >        BUG_ON(!sgt);
    >  }
    >
    > -static void sgtable_fill_kmalloc(struct sg_table *sgt, u32 pa, size_t len)
    > +static void sgtable_fill_kmalloc(struct sg_table *sgt, u32 pa, u32 da,
    > +                                                               size_t len)
    >  {
    >        unsigned int i;
    >        struct scatterlist *sg;
    > @@ -420,7 +431,8 @@ static void sgtable_fill_kmalloc(struct sg_table *sgt, u32 pa, size_t len)
    >        for_each_sg(sgt->sgl, sg, sgt->nents, i) {
    >                size_t bytes;
    >
    > -               bytes = iopgsz_max(len);
    > +               bytes = max_alignment(da | pa);
    > +               bytes = min(bytes, (size_t)iopgsz_max(len));

    Why the size_t casting?

    Otherwise:
    Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>

    --
    Felipe Contreras
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2010-10-10 17:25    [W:0.028 / U:1.288 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site