[SPARC64]: Eliminate PCI IOMMU dma mapping size limit.

The hairy fast allocator in the sparc64 PCI IOMMU code
has a hard limit of 256 pages.  Certain devices can
exceed this when performing very large I/Os.

So replace with a more simple allocator, based largely
upon the arch/ppc64/kernel/iommu.c code.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 20 deletions

diff --git a/include/asm-sparc64/pbm.h b/include/asm-sparc64/pbm.h
index c067407de0b0..dd35a2c7798a 100644
--- a/include/asm-sparc64/pbm.h
+++ b/include/asm-sparc64/pbm.h
@@ -27,23 +27,27 @@
  * PCI bus.
  */
 
-#define PBM_LOGCLUSTERS 3
-#define PBM_NCLUSTERS (1 << PBM_LOGCLUSTERS)
-
 struct pci_controller_info;
 
 /* This contains the software state necessary to drive a PCI
  * controller's IOMMU.
  */
+struct pci_iommu_arena {
+        unsigned long   *map;
+        unsigned int    hint;
+        unsigned int    limit;
+};
+
 struct pci_iommu {
         /* This protects the controller's IOMMU and all
          * streaming buffers underneath.
          */
         spinlock_t      lock;
 
+        struct pci_iommu_arena arena;
+
         /* IOMMU page table, a linear array of ioptes. */
         iopte_t         *page_table;            /* The page table itself. */
-        int             page_table_sz_bits;     /* log2 of ow many pages does it map? */
 
         /* Base PCI memory space address where IOMMU mappings
          * begin.
@@ -62,12 +66,6 @@ struct pci_iommu {
          */
         unsigned long   write_complete_reg;
 
-        /* The lowest used consistent mapping entry.  Since
-         * we allocate consistent maps out of cluster 0 this
-         * is relative to the beginning of closter 0.
-         */
-        u32             lowest_consistent_map;
-
         /* In order to deal with some buggy third-party PCI bridges that
          * do wrong prefetching, we never mark valid mappings as invalid.
          * Instead we point them at this dummy page.
@@ -75,16 +73,6 @@ struct pci_iommu {
         unsigned long   dummy_page;
         unsigned long   dummy_page_pa;
 
-        /* If PBM_NCLUSTERS is ever decreased to 4 or lower,
-         * or if largest supported page_table_sz * 8K goes above
-         * 2GB, you must increase the size of the type of
-         * these counters.  You have been duly warned. -DaveM
-         */
-        struct {
-                u16     next;
-                u16     flush;
-        } alloc_info[PBM_NCLUSTERS];
-
         /* CTX allocation. */
         unsigned long ctx_lowest_free;
         unsigned long ctx_bitmap[IOMMU_NUM_CTXS / (sizeof(unsigned long) * 8)];