From: Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx>
Superpage addresses should be aligned on mapping size of 4KB, 64KB,
1MB and 16MB respectively both for physical and device virtual
addresses.
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx>
---
arch/arm/plat-omap/iovmm.c | 122 +++++++++++++++++++++++++------------------
1 files changed, 71 insertions(+), 51 deletions(-)
diff --git a/arch/arm/plat-omap/iovmm.c b/arch/arm/plat-omap/iovmm.c
index 65c6d1f..111fbca 100644
--- a/arch/arm/plat-omap/iovmm.c
+++ b/arch/arm/plat-omap/iovmm.c
@@ -1,7 +1,7 @@
/*
* omap iommu: simple virtual address space management
*
- * Copyright (C) 2008-2009 Nokia Corporation
+ * Copyright (C) 2008-2010 Nokia Corporation
*
* Written by Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx>
*
@@ -87,33 +87,6 @@ static size_t sgtable_len(const struct sg_table *sgt)
}
#define sgtable_ok(x) (!!sgtable_len(x))
-/*
- * calculate the optimal number sg elements from total bytes based on
- * iommu superpages
- */
-static unsigned int sgtable_nents(size_t bytes)
-{
- int i;
- unsigned int nr_entries;
- const unsigned long pagesize[] = { SZ_16M, SZ_1M, SZ_64K, SZ_4K, };
-
- 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];
- }
- }
- BUG_ON(bytes);
-
- return nr_entries;
-}
-
/* allocate and initialize sg_table header(a kind of 'superblock') */
static struct sg_table *sgtable_alloc(const size_t bytes, u32 flags)
{
@@ -127,13 +100,8 @@ 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 (!nr_entries)
- return ERR_PTR(-EINVAL);
- } else
- nr_entries = bytes / PAGE_SIZE;
+ /* FIXME: Maximam number of entries are always prepared. */
+ nr_entries = bytes / PAGE_SIZE;
sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
if (!sgt)
@@ -270,7 +238,7 @@ static struct iovm_struct *alloc_iovm_area(struct iommu *obj, u32 da,
start = da;
alignement = PAGE_SIZE;
- if (flags & IOVMF_DA_ANON) {
+ if ((da == 0) && (flags & IOVMF_DA_ANON)) {
/*
* Reserve the first page for NULL
*/
@@ -404,29 +372,80 @@ 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 u32 __alloc_area_by_size(u32 start, u32 end, size_t unit,
+ struct scatterlist **_sg)
{
- unsigned int i;
+ u32 e;
struct scatterlist *sg;
- void *va;
- va = phys_to_virt(pa);
+ sg = *_sg;
+ while ((e = start + unit) <= end) {
- for_each_sg(sgt->sgl, sg, sgt->nents, i) {
- size_t bytes;
+ pr_debug("%s: %08x %8d KB\n",
+ __func__, start, (e - start) / SZ_1K);
- bytes = iopgsz_max(len);
+ sg_set_buf(sg++, (const void *)start, unit);
+ start += unit;
+ }
+ *_sg = sg;
- BUG_ON(!iopgsz_ok(bytes));
+ return start;
+}
- sg_set_buf(sg, phys_to_virt(pa), bytes);
- /*
- * 'pa' is cotinuous(linear).
- */
- pa += bytes;
- len -= bytes;
+static void alloc_area_by_size(u32 start, u32 end, u32 unit,
+ struct scatterlist **_sg)
+{
+ u32 addr;
+
+ if (unit == 0)
+ return;
+
+ if (start == end)
+ return;
+
+ addr = ALIGN(start, unit);
+ if (addr > end) {
+ /* retry with smaller granularity */
+ alloc_area_by_size(start, end, iopgsz_max(unit - 1), _sg);
+ return;
+ }
+ /* lower chuck with smaller granularity */
+ alloc_area_by_size(start, addr, iopgsz_max(unit - 1), _sg);
+
+ addr = __alloc_area_by_size(addr, end, unit, _sg);
+ if (addr < end)
+ /* higher chuck with smaller granularity */
+ alloc_area_by_size(addr, end, iopgsz_max(unit - 1), _sg);
+}
+
+#ifdef DEBUG
+static void sgtable_dump_entries(struct sg_table *sgt)
+{
+ unsigned int i;
+ struct scatterlist *sg;
+
+ for_each_sg(sgt->sgl, sg, sgt->nents, i) {
+ pr_debug("%s: %3d %p %6d KB\n",
+ __func__, i, sg_virt(sg), sg_dma_len(sg) / SZ_1K);
}
- BUG_ON(len);
+}
+#else
+static inline void sgtable_dump_entries(struct sg_table *sgt) { }
+#endif
+
+static void sgtable_fill_kmalloc(struct sg_table *sgt, u32 pa, size_t len)
+{
+ struct scatterlist *sg;
+ u32 va;
+
+ sg = sgt->sgl;
+ va = (u32)phys_to_virt(pa);
+
+ alloc_area_by_size(va, va + len, SZ_16M, &sg);
+ /* update actual nents */
+ sgt->nents = sg - sgt->sgl;
+
+ sgtable_dump_entries(sgt);
}
static inline void sgtable_drain_kmalloc(struct sg_table *sgt)
@@ -571,6 +590,7 @@ static u32 map_iommu_region(struct iommu *obj, u32 da,
mutex_lock(&obj->mmap_lock);
+ da = da ? da : sg_phys(sgt->sgl) & ~(SZ_64K - 1);
new = alloc_iovm_area(obj, da, bytes, flags);
if (IS_ERR(new)) {
err = PTR_ERR(new);
--
1.7.1.rc1
--
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