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-rw-r--r--arch/sparc64/kernel/iommu.c125
1 files changed, 81 insertions, 44 deletions
diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
index 5623a4d59df..90a5907080a 100644
--- a/arch/sparc64/kernel/iommu.c
+++ b/arch/sparc64/kernel/iommu.c
@@ -1,6 +1,6 @@
/* iommu.c: Generic sparc64 IOMMU support.
*
- * Copyright (C) 1999, 2007 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1999, 2007, 2008 David S. Miller (davem@davemloft.net)
* Copyright (C) 1999, 2000 Jakub Jelinek (jakub@redhat.com)
*/
@@ -10,6 +10,7 @@
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/errno.h>
+#include <linux/iommu-helper.h>
#ifdef CONFIG_PCI
#include <linux/pci.h>
@@ -41,7 +42,7 @@
"i" (ASI_PHYS_BYPASS_EC_E))
/* Must be invoked under the IOMMU lock. */
-static void __iommu_flushall(struct iommu *iommu)
+static void iommu_flushall(struct iommu *iommu)
{
if (iommu->iommu_flushinv) {
iommu_write(iommu->iommu_flushinv, ~(u64)0);
@@ -83,54 +84,91 @@ static inline void iopte_make_dummy(struct iommu *iommu, iopte_t *iopte)
iopte_val(*iopte) = val;
}
-/* Based largely upon the ppc64 iommu allocator. */
-static long arena_alloc(struct iommu *iommu, unsigned long npages)
+/* Based almost entirely upon the ppc64 iommu allocator. If you use the 'handle'
+ * facility it must all be done in one pass while under the iommu lock.
+ *
+ * On sun4u platforms, we only flush the IOMMU once every time we've passed
+ * over the entire page table doing allocations. Therefore we only ever advance
+ * the hint and cannot backtrack it.
+ */
+unsigned long iommu_range_alloc(struct device *dev,
+ struct iommu *iommu,
+ unsigned long npages,
+ unsigned long *handle)
{
+ unsigned long n, end, start, limit, boundary_size;
struct iommu_arena *arena = &iommu->arena;
- unsigned long n, i, start, end, limit;
- int pass;
+ int pass = 0;
+
+ /* This allocator was derived from x86_64's bit string search */
+
+ /* Sanity check */
+ if (unlikely(npages == 0)) {
+ if (printk_ratelimit())
+ WARN_ON(1);
+ return DMA_ERROR_CODE;
+ }
+
+ if (handle && *handle)
+ start = *handle;
+ else
+ start = arena->hint;
limit = arena->limit;
- start = arena->hint;
- pass = 0;
-again:
- n = find_next_zero_bit(arena->map, limit, start);
- end = n + npages;
- if (unlikely(end >= limit)) {
+ /* The case below can happen if we have a small segment appended
+ * to a large, or when the previous alloc was at the very end of
+ * the available space. If so, go back to the beginning and flush.
+ */
+ if (start >= limit) {
+ start = 0;
+ if (iommu->flush_all)
+ iommu->flush_all(iommu);
+ }
+
+ again:
+
+ if (dev)
+ boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
+ 1 << IO_PAGE_SHIFT);
+ else
+ boundary_size = ALIGN(1UL << 32, 1 << IO_PAGE_SHIFT);
+
+ n = iommu_area_alloc(arena->map, limit, start, npages, 0,
+ boundary_size >> IO_PAGE_SHIFT, 0);
+ if (n == -1) {
if (likely(pass < 1)) {
- limit = start;
+ /* First failure, rescan from the beginning. */
start = 0;
- __iommu_flushall(iommu);
+ if (iommu->flush_all)
+ iommu->flush_all(iommu);
pass++;
goto again;
} else {
- /* Scanned the whole thing, give up. */
- return -1;
+ /* Second failure, give up */
+ return DMA_ERROR_CODE;
}
}
- for (i = n; i < end; i++) {
- if (test_bit(i, arena->map)) {
- start = i + 1;
- goto again;
- }
- }
-
- for (i = n; i < end; i++)
- __set_bit(i, arena->map);
+ end = n + npages;
arena->hint = end;
+ /* Update handle for SG allocations */
+ if (handle)
+ *handle = end;
+
return n;
}
-static void arena_free(struct iommu_arena *arena, unsigned long base, unsigned long npages)
+void iommu_range_free(struct iommu *iommu, dma_addr_t dma_addr, unsigned long npages)
{
- unsigned long i;
+ struct iommu_arena *arena = &iommu->arena;
+ unsigned long entry;
- for (i = base; i < (base + npages); i++)
- __clear_bit(i, arena->map);
+ entry = (dma_addr - iommu->page_table_map_base) >> IO_PAGE_SHIFT;
+
+ iommu_area_free(arena->map, entry, npages);
}
int iommu_table_init(struct iommu *iommu, int tsbsize,
@@ -156,6 +194,9 @@ int iommu_table_init(struct iommu *iommu, int tsbsize,
}
iommu->arena.limit = num_tsb_entries;
+ if (tlb_type != hypervisor)
+ iommu->flush_all = iommu_flushall;
+
/* Allocate and initialize the dummy page which we
* set inactive IO PTEs to point to.
*/
@@ -192,22 +233,18 @@ out_free_map:
return -ENOMEM;
}
-static inline iopte_t *alloc_npages(struct iommu *iommu, unsigned long npages)
+static inline iopte_t *alloc_npages(struct device *dev, struct iommu *iommu,
+ unsigned long npages)
{
- long entry;
+ unsigned long entry;
- entry = arena_alloc(iommu, npages);
- if (unlikely(entry < 0))
+ entry = iommu_range_alloc(dev, iommu, npages, NULL);
+ if (unlikely(entry == DMA_ERROR_CODE))
return NULL;
return iommu->page_table + entry;
}
-static inline void free_npages(struct iommu *iommu, dma_addr_t base, unsigned long npages)
-{
- arena_free(&iommu->arena, base >> IO_PAGE_SHIFT, npages);
-}
-
static int iommu_alloc_ctx(struct iommu *iommu)
{
int lowest = iommu->ctx_lowest_free;
@@ -258,7 +295,7 @@ static void *dma_4u_alloc_coherent(struct device *dev, size_t size,
iommu = dev->archdata.iommu;
spin_lock_irqsave(&iommu->lock, flags);
- iopte = alloc_npages(iommu, size >> IO_PAGE_SHIFT);
+ iopte = alloc_npages(dev, iommu, size >> IO_PAGE_SHIFT);
spin_unlock_irqrestore(&iommu->lock, flags);
if (unlikely(iopte == NULL)) {
@@ -296,7 +333,7 @@ static void dma_4u_free_coherent(struct device *dev, size_t size,
spin_lock_irqsave(&iommu->lock, flags);
- free_npages(iommu, dvma - iommu->page_table_map_base, npages);
+ iommu_range_free(iommu, dvma, npages);
spin_unlock_irqrestore(&iommu->lock, flags);
@@ -327,7 +364,7 @@ static dma_addr_t dma_4u_map_single(struct device *dev, void *ptr, size_t sz,
npages >>= IO_PAGE_SHIFT;
spin_lock_irqsave(&iommu->lock, flags);
- base = alloc_npages(iommu, npages);
+ base = alloc_npages(dev, iommu, npages);
ctx = 0;
if (iommu->iommu_ctxflush)
ctx = iommu_alloc_ctx(iommu);
@@ -465,7 +502,7 @@ static void dma_4u_unmap_single(struct device *dev, dma_addr_t bus_addr,
for (i = 0; i < npages; i++)
iopte_make_dummy(iommu, base + i);
- free_npages(iommu, bus_addr - iommu->page_table_map_base, npages);
+ iommu_range_free(iommu, bus_addr, npages);
iommu_free_ctx(iommu, ctx);
@@ -503,7 +540,7 @@ static int dma_4u_map_sg(struct device *dev, struct scatterlist *sglist,
spin_lock_irqsave(&iommu->lock, flags);
- base = alloc_npages(iommu, npages);
+ base = alloc_npages(dev, iommu, npages);
ctx = 0;
if (iommu->iommu_ctxflush)
ctx = iommu_alloc_ctx(iommu);
@@ -592,7 +629,7 @@ static void dma_4u_unmap_sg(struct device *dev, struct scatterlist *sglist,
for (i = 0; i < npages; i++)
iopte_make_dummy(iommu, base + i);
- free_npages(iommu, bus_addr - iommu->page_table_map_base, npages);
+ iommu_range_free(iommu, bus_addr, npages);
iommu_free_ctx(iommu, ctx);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-28 23:09:45 +0000