Merge branch 'generic-iommu-allocator'

Sowmini Varadhan says:

====================
Generic IOMMU pooled allocator

Investigation of network performance on Sparc shows a high
degree of locking contention in the IOMMU allocator, and it
was noticed that the PowerPC code has a better locking model.

This patch series tries to extract the generic parts of the
PowerPC code so that it can be shared across multiple PCI
devices and architectures.

v10: resend patchv9 without RFC tag, and a new mail Message-Id,
(previous non-RFC attempt did not show up on the patchwork queue?)

Full revision history below:
v2 changes:
  - incorporate David Miller editorial comments: sparc specific
    fields moved from iommu-common into sparc's iommu_64.h
  - make the npools value an input parameter, for the case when
    the iommu map size is not very large
  - cookie_to_index mapping, and optimizations for span-boundary
    check, for use case such as LDC.

v3: eliminate iommu_sparc, rearrange the ->demap indirection to
    be invoked under the pool lock.

v4: David Miller review changes:
  - s/IOMMU_ERROR_CODE/DMA_ERROR_CODE
  - page_table_map_base and page_table_shift are unsigned long, not u32.

v5: removed ->cookie_to_index and ->demap indirection from the
    iommu_tbl_ops The caller needs to call these functions as needed,
    before invoking the generic arena allocator functions.
    Added the "skip_span_boundary" argument to iommu_tbl_pool_init() for
    those callers like LDC which do no care about span boundary checks.

v6: removed iommu_tbl_ops, and instead pass the ->flush_all as
    an indirection to iommu_tbl_pool_init(); only invoke ->flush_all
    when there is no large_pool, based on the assumption that large-pool
    usage is infrequently encountered

v7: moved pool_hash initialization to lib/iommu-common.c and cleaned up
    code duplication from sun4v/sun4u/ldc.

v8: Addresses BenH comments with one exception: I've left the
    IOMMU_POOL_HASH as is, so that powerpc can tailor it to their
    convenience.  Discard trylock for simple spin_lock to acquire pool

v9: Addresses latest BenH comments: need_flush checks, add support
    for dma mask and align_order.

v10: resend without RFC tag, and new mail Message-Id.
====================

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

1 files changed, 3 insertions, 4 deletions

diff --git a/arch/sparc/include/asm/iommu_64.h b/arch/sparc/include/asm/iommu_64.h
index 2b9321ab064d..e3cd4493d81d 100644
--- a/arch/sparc/include/asm/iommu_64.h
+++ b/arch/sparc/include/asm/iommu_64.h
@@ -16,6 +16,7 @@
 #define IOPTE_WRITE   0x0000000000000002UL
 
 #define IOMMU_NUM_CTXS	4096
+#include <linux/iommu-common.h>
 
 struct iommu_arena {
 	unsigned long	*map;
@@ -24,11 +25,10 @@ struct iommu_arena {
 };
 
 struct iommu {
+	struct iommu_table	tbl;
 	spinlock_t		lock;
-	struct iommu_arena	arena;
-	void			(*flush_all)(struct iommu *);
+	u32			dma_addr_mask;
 	iopte_t			*page_table;
-	u32			page_table_map_base;
 	unsigned long		iommu_control;
 	unsigned long		iommu_tsbbase;
 	unsigned long		iommu_flush;
@@ -40,7 +40,6 @@ struct iommu {
 	unsigned long		dummy_page_pa;
 	unsigned long		ctx_lowest_free;
 	DECLARE_BITMAP(ctx_bitmap, IOMMU_NUM_CTXS);
-	u32			dma_addr_mask;
 };
 
 struct strbuf {