[PATCH -mm 3/3] parisc: make the IOMMUs respect the segment boundary limits

From: FUJITA Tomonori
Date: Sun Mar 02 2008 - 01:21:16 EST

This patch makes PARISC's two IOMMU implementations not allocate a
memory area spanning LLD's segment boundary.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx>
Cc: Kyle McMartin <kyle@xxxxxxxxxxxxxxxx>
Cc: Matthew Wilcox <matthew@xxxxxx>
Cc: Grant Grundler <grundler@xxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/parisc/Kconfig | 5 ++++
drivers/parisc/ccio-dma.c | 13 ++++++++++-
drivers/parisc/sba_iommu.c | 48 +++++++++++++++++++++++++++++++++----------
3 files changed, 53 insertions(+), 13 deletions(-)

diff --git a/drivers/parisc/Kconfig b/drivers/parisc/Kconfig
index 1d3b84b..553a990 100644
--- a/drivers/parisc/Kconfig
+++ b/drivers/parisc/Kconfig
@@ -103,6 +103,11 @@ config IOMMU_SBA
depends on PCI_LBA
default PCI_LBA

+config IOMMU_HELPER
+ bool
+ depends on IOMMU_SBA || IOMMU_CCIO
+ default y
+
#config PCI_EPIC
# bool "EPIC/SAGA PCI support"
# depends on PCI
diff --git a/drivers/parisc/ccio-dma.c b/drivers/parisc/ccio-dma.c
index 1695fac..2f3b364 100644
--- a/drivers/parisc/ccio-dma.c
+++ b/drivers/parisc/ccio-dma.c
@@ -43,6 +43,7 @@
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/scatterlist.h>
+#include <linux/iommu-helper.h>

#include <asm/byteorder.h>
#include <asm/cache.h> /* for L1_CACHE_BYTES */
@@ -302,9 +303,13 @@ static int ioc_count;
*/
#define CCIO_SEARCH_LOOP(ioc, res_idx, mask, size) \
for(; res_ptr < res_end; ++res_ptr) { \
- if(0 == (*res_ptr & mask)) { \
+ int ret;\
+ unsigned int idx;\
+ idx = (unsigned int)((unsigned long)res_ptr - (unsigned long)ioc->res_map); \
+ ret = iommu_is_span_boundary(idx << 3, pages_needed, 0, boundary_size);\
+ if((0 == (*res_ptr & mask)) && !ret) { \
*res_ptr |= mask; \
- res_idx = (unsigned int)((unsigned long)res_ptr - (unsigned long)ioc->res_map); \
+ res_idx = idx;\
ioc->res_hint = res_idx + (size >> 3); \
goto resource_found; \
} \
@@ -345,6 +350,7 @@ ccio_alloc_range(struct ioc *ioc, struct device *dev, size_t size)
{
unsigned int pages_needed = size >> IOVP_SHIFT;
unsigned int res_idx;
+ unsigned long boundary_size;
#ifdef CCIO_SEARCH_TIME
unsigned long cr_start = mfctl(16);
#endif
@@ -360,6 +366,9 @@ ccio_alloc_range(struct ioc *ioc, struct device *dev, size_t size)
** ggg sacrifices another 710 to the computer gods.
*/

+ boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1, 1 << IOVP_SHIFT);
+ boundary_size >>= IOVP_SHIFT;
+
if (pages_needed <= 8) {
/*
* LAN traffic will not thrash the TLB IFF the same NIC
diff --git a/drivers/parisc/sba_iommu.c b/drivers/parisc/sba_iommu.c
index 7d58bd2..e834127 100644
--- a/drivers/parisc/sba_iommu.c
+++ b/drivers/parisc/sba_iommu.c
@@ -29,6 +29,7 @@
#include <linux/string.h>
#include <linux/pci.h>
#include <linux/scatterlist.h>
+#include <linux/iommu-helper.h>

#include <asm/byteorder.h>
#include <asm/io.h>
@@ -313,6 +314,12 @@ sba_dump_sg( struct ioc *ioc, struct scatterlist *startsg, int nents)
#define RESMAP_MASK(n) (~0UL << (BITS_PER_LONG - (n)))
#define RESMAP_IDX_MASK (sizeof(unsigned long) - 1)

+unsigned long ptr_to_pide(struct ioc *ioc, unsigned long *res_ptr,
+ unsigned int bitshiftcnt)
+{
+ return (((unsigned long)res_ptr - (unsigned long)ioc->res_map) << 3)
+ + bitshiftcnt;
+}

/**
* sba_search_bitmap - find free space in IO PDIR resource bitmap
@@ -324,19 +331,36 @@ sba_dump_sg( struct ioc *ioc, struct scatterlist *startsg, int nents)
* Cool perf optimization: search for log2(size) bits at a time.
*/
static SBA_INLINE unsigned long
-sba_search_bitmap(struct ioc *ioc, unsigned long bits_wanted)
+sba_search_bitmap(struct ioc *ioc, struct device *dev,
+ unsigned long bits_wanted)
{
unsigned long *res_ptr = ioc->res_hint;
unsigned long *res_end = (unsigned long *) &(ioc->res_map[ioc->res_size]);
- unsigned long pide = ~0UL;
+ unsigned long pide = ~0UL, tpide;
+ unsigned long boundary_size;
+ unsigned long shift;
+ int ret;
+
+ boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1, 1 << IOVP_SHIFT);
+ boundary_size >>= IOVP_SHIFT;
+
+#if defined(ZX1_SUPPORT)
+ BUG_ON(ioc->ibase & ~IOVP_MASK);
+ shift = ioc->ibase >> IOVP_SHIFT;
+#else
+ shift = 0;
+#endif

if (bits_wanted > (BITS_PER_LONG/2)) {
/* Search word at a time - no mask needed */
for(; res_ptr < res_end; ++res_ptr) {
- if (*res_ptr == 0) {
+ tpide = ptr_to_pide(ioc, res_ptr, 0);
+ ret = iommu_is_span_boundary(tpide, bits_wanted,
+ shift,
+ boundary_size);
+ if ((*res_ptr == 0) && !ret) {
*res_ptr = RESMAP_MASK(bits_wanted);
- pide = ((unsigned long)res_ptr - (unsigned long)ioc->res_map);
- pide <<= 3; /* convert to bit address */
+ pide = tpide;
break;
}
}
@@ -365,11 +389,13 @@ sba_search_bitmap(struct ioc *ioc, unsigned long bits_wanted)
{
DBG_RES(" %p %lx %lx\n", res_ptr, mask, *res_ptr);
WARN_ON(mask == 0);
- if(((*res_ptr) & mask) == 0) {
+ tpide = ptr_to_pide(ioc, res_ptr, bitshiftcnt);
+ ret = iommu_is_span_boundary(tpide, bits_wanted,
+ shift,
+ boundary_size);
+ if ((((*res_ptr) & mask) == 0) && !ret) {
*res_ptr |= mask; /* mark resources busy! */
- pide = ((unsigned long)res_ptr - (unsigned long)ioc->res_map);
- pide <<= 3; /* convert to bit address */
- pide += bitshiftcnt;
+ pide = tpide;
break;
}
mask >>= o;
@@ -412,9 +438,9 @@ sba_alloc_range(struct ioc *ioc, struct device *dev, size_t size)
#endif
unsigned long pide;

- pide = sba_search_bitmap(ioc, pages_needed);
+ pide = sba_search_bitmap(ioc, dev, pages_needed);
if (pide >= (ioc->res_size << 3)) {
- pide = sba_search_bitmap(ioc, pages_needed);
+ pide = sba_search_bitmap(ioc, dev, pages_needed);
if (pide >= (ioc->res_size << 3))
panic("%s: I/O MMU @ %p is out of mapping resources\n",
__FILE__, ioc->ioc_hpa);
--
1.5.3.7

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