OMAP: iommu: create new api to set valid da range

Some IOMMUs cannot use the whole 0x0 - 0xFFFFFFFF range.
With this new API the valid range can be set.

Signed-off-by: Fernando Guzman Lugo <x0095840@ti.com>
Acked-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>

1 files changed, 8 insertions, 7 deletions

diff --git a/arch/arm/plat-omap/iovmm.c b/arch/arm/plat-omap/iovmm.c
index fa6e64332a9e..6dc1296c8c77 100644
--- a/arch/arm/plat-omap/iovmm.c
+++ b/arch/arm/plat-omap/iovmm.c
@@ -280,13 +280,14 @@ static struct iovm_struct *alloc_iovm_area(struct iommu *obj, u32 da,
         alignement = PAGE_SIZE;
 
         if (flags & IOVMF_DA_ANON) {
-                /*
-                 * Reserve the first page for NULL
-                 */
-                start = PAGE_SIZE;
+                start = obj->da_start;
+
                 if (flags & IOVMF_LINEAR)
                         alignement = iopgsz_max(bytes);
                 start = roundup(start, alignement);
+        } else if (start < obj->da_start || start > obj->da_end ||
+                                        obj->da_end - start < bytes) {
+                return ERR_PTR(-EINVAL);
         }
 
         tmp = NULL;
@@ -299,16 +300,16 @@ static struct iovm_struct *alloc_iovm_area(struct iommu *obj, u32 da,
                 if (prev_end > start)
                         break;
 
-                if (start + bytes <= tmp->da_start)
+                if (tmp->da_start > start && (tmp->da_start - start) >= bytes)
                         goto found;
 
-                if (flags & IOVMF_DA_ANON)
+                if (tmp->da_end >= start && flags & IOVMF_DA_ANON)
                         start = roundup(tmp->da_end + 1, alignement);
 
                 prev_end = tmp->da_end;
         }
 
-        if ((start >= prev_end) && (ULONG_MAX - start + 1 >= bytes))
+        if ((start >= prev_end) && (obj->da_end - start >= bytes))
                 goto found;
 
         dev_dbg(obj->dev, "%s: no space to fit %08x(%x) flags: %08x\n",