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-rw-r--r--drivers/infiniband/hw/ipath/ipath_driver.c60
-rw-r--r--drivers/infiniband/hw/ipath/ipath_file_ops.c55
-rw-r--r--drivers/infiniband/hw/ipath/ipath_iba6120.c2
-rw-r--r--drivers/infiniband/hw/ipath/ipath_init_chip.c56
-rw-r--r--drivers/infiniband/hw/ipath/ipath_intr.c2
-rw-r--r--drivers/infiniband/hw/ipath/ipath_kernel.h20
-rw-r--r--drivers/infiniband/hw/ipath/ipath_user_pages.c56
-rw-r--r--drivers/infiniband/hw/ipath/ipath_wc_ppc64.c20
8 files changed, 198 insertions, 73 deletions
diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c
index 467816043d1..68fc9b5a4ad 100644
--- a/drivers/infiniband/hw/ipath/ipath_driver.c
+++ b/drivers/infiniband/hw/ipath/ipath_driver.c
@@ -755,8 +755,8 @@ static void get_rhf_errstring(u32 err, char *msg, size_t len)
static inline void *ipath_get_egrbuf(struct ipath_devdata *dd, u32 bufnum,
int err)
{
- return dd->ipath_port0_skbs ?
- (void *)dd->ipath_port0_skbs[bufnum]->data : NULL;
+ return dd->ipath_port0_skbinfo ?
+ (void *) dd->ipath_port0_skbinfo[bufnum].skb->data : NULL;
}
/**
@@ -778,31 +778,34 @@ struct sk_buff *ipath_alloc_skb(struct ipath_devdata *dd,
*/
/*
- * We need 4 extra bytes for unaligned transfer copying
+ * We need 2 extra bytes for ipath_ether data sent in the
+ * key header. In order to keep everything dword aligned,
+ * we'll reserve 4 bytes.
*/
+ len = dd->ipath_ibmaxlen + 4;
+
if (dd->ipath_flags & IPATH_4BYTE_TID) {
- /* we need a 4KB multiple alignment, and there is no way
+ /* We need a 2KB multiple alignment, and there is no way
* to do it except to allocate extra and then skb_reserve
* enough to bring it up to the right alignment.
*/
- len = dd->ipath_ibmaxlen + 4 + (1 << 11) - 1;
+ len += 2047;
}
- else
- len = dd->ipath_ibmaxlen + 4;
+
skb = __dev_alloc_skb(len, gfp_mask);
if (!skb) {
ipath_dev_err(dd, "Failed to allocate skbuff, length %u\n",
len);
goto bail;
}
+
+ skb_reserve(skb, 4);
+
if (dd->ipath_flags & IPATH_4BYTE_TID) {
- u32 una = ((1 << 11) - 1) & (unsigned long)(skb->data + 4);
+ u32 una = (unsigned long)skb->data & 2047;
if (una)
- skb_reserve(skb, 4 + (1 << 11) - una);
- else
- skb_reserve(skb, 4);
- } else
- skb_reserve(skb, 4);
+ skb_reserve(skb, 2048 - una);
+ }
bail:
return skb;
@@ -1345,8 +1348,9 @@ int ipath_create_rcvhdrq(struct ipath_devdata *dd,
ipath_cdbg(VERBOSE, "reuse port %d rcvhdrq @%p %llx phys; "
"hdrtailaddr@%p %llx physical\n",
pd->port_port, pd->port_rcvhdrq,
- pd->port_rcvhdrq_phys, pd->port_rcvhdrtail_kvaddr,
- (unsigned long long)pd->port_rcvhdrqtailaddr_phys);
+ (unsigned long long) pd->port_rcvhdrq_phys,
+ pd->port_rcvhdrtail_kvaddr, (unsigned long long)
+ pd->port_rcvhdrqtailaddr_phys);
/* clear for security and sanity on each use */
memset(pd->port_rcvhdrq, 0, pd->port_rcvhdrq_size);
@@ -1827,17 +1831,22 @@ void ipath_free_pddata(struct ipath_devdata *dd, struct ipath_portdata *pd)
kfree(pd->port_rcvegrbuf_phys);
pd->port_rcvegrbuf_phys = NULL;
pd->port_rcvegrbuf_chunks = 0;
- } else if (pd->port_port == 0 && dd->ipath_port0_skbs) {
+ } else if (pd->port_port == 0 && dd->ipath_port0_skbinfo) {
unsigned e;
- struct sk_buff **skbs = dd->ipath_port0_skbs;
+ struct ipath_skbinfo *skbinfo = dd->ipath_port0_skbinfo;
- dd->ipath_port0_skbs = NULL;
- ipath_cdbg(VERBOSE, "free closed port %d ipath_port0_skbs "
- "@ %p\n", pd->port_port, skbs);
+ dd->ipath_port0_skbinfo = NULL;
+ ipath_cdbg(VERBOSE, "free closed port %d "
+ "ipath_port0_skbinfo @ %p\n", pd->port_port,
+ skbinfo);
for (e = 0; e < dd->ipath_rcvegrcnt; e++)
- if (skbs[e])
- dev_kfree_skb(skbs[e]);
- vfree(skbs);
+ if (skbinfo[e].skb) {
+ pci_unmap_single(dd->pcidev, skbinfo[e].phys,
+ dd->ipath_ibmaxlen,
+ PCI_DMA_FROMDEVICE);
+ dev_kfree_skb(skbinfo[e].skb);
+ }
+ vfree(skbinfo);
}
kfree(pd->port_tid_pg_list);
vfree(pd->subport_uregbase);
@@ -1934,7 +1943,7 @@ static void cleanup_device(struct ipath_devdata *dd)
if (dd->ipath_pioavailregs_dma) {
dma_free_coherent(&dd->pcidev->dev, PAGE_SIZE,
- dd->ipath_pioavailregs_dma,
+ (void *) dd->ipath_pioavailregs_dma,
dd->ipath_pioavailregs_phys);
dd->ipath_pioavailregs_dma = NULL;
}
@@ -1947,6 +1956,7 @@ static void cleanup_device(struct ipath_devdata *dd)
if (dd->ipath_pageshadow) {
struct page **tmpp = dd->ipath_pageshadow;
+ dma_addr_t *tmpd = dd->ipath_physshadow;
int i, cnt = 0;
ipath_cdbg(VERBOSE, "Unlocking any expTID pages still "
@@ -1957,6 +1967,8 @@ static void cleanup_device(struct ipath_devdata *dd)
for (i = port_tidbase; i < maxtid; i++) {
if (!tmpp[i])
continue;
+ pci_unmap_page(dd->pcidev, tmpd[i],
+ PAGE_SIZE, PCI_DMA_FROMDEVICE);
ipath_release_user_pages(&tmpp[i], 1);
tmpp[i] = NULL;
cnt++;
diff --git a/drivers/infiniband/hw/ipath/ipath_file_ops.c b/drivers/infiniband/hw/ipath/ipath_file_ops.c
index d4fc4118ddd..64221b93776 100644
--- a/drivers/infiniband/hw/ipath/ipath_file_ops.c
+++ b/drivers/infiniband/hw/ipath/ipath_file_ops.c
@@ -364,11 +364,14 @@ static int ipath_tid_update(struct ipath_portdata *pd, struct file *fp,
"vaddr %lx\n", i, tid + tidoff, vaddr);
/* we "know" system pages and TID pages are same size */
dd->ipath_pageshadow[porttid + tid] = pagep[i];
+ dd->ipath_physshadow[porttid + tid] = ipath_map_page(
+ dd->pcidev, pagep[i], 0, PAGE_SIZE,
+ PCI_DMA_FROMDEVICE);
/*
* don't need atomic or it's overhead
*/
__set_bit(tid, tidmap);
- physaddr = page_to_phys(pagep[i]);
+ physaddr = dd->ipath_physshadow[porttid + tid];
ipath_stats.sps_pagelocks++;
ipath_cdbg(VERBOSE,
"TID %u, vaddr %lx, physaddr %llx pgp %p\n",
@@ -402,6 +405,9 @@ static int ipath_tid_update(struct ipath_portdata *pd, struct file *fp,
tid);
dd->ipath_f_put_tid(dd, &tidbase[tid], 1,
dd->ipath_tidinvalid);
+ pci_unmap_page(dd->pcidev,
+ dd->ipath_physshadow[porttid + tid],
+ PAGE_SIZE, PCI_DMA_FROMDEVICE);
dd->ipath_pageshadow[porttid + tid] = NULL;
ipath_stats.sps_pageunlocks++;
}
@@ -515,6 +521,9 @@ static int ipath_tid_free(struct ipath_portdata *pd, unsigned subport,
pd->port_pid, tid);
dd->ipath_f_put_tid(dd, &tidbase[tid], 1,
dd->ipath_tidinvalid);
+ pci_unmap_page(dd->pcidev,
+ dd->ipath_physshadow[porttid + tid],
+ PAGE_SIZE, PCI_DMA_FROMDEVICE);
ipath_release_user_pages(
&dd->ipath_pageshadow[porttid + tid], 1);
dd->ipath_pageshadow[porttid + tid] = NULL;
@@ -711,7 +720,7 @@ static int ipath_manage_rcvq(struct ipath_portdata *pd, unsigned subport,
* updated and correct itself, even in the face of software
* bugs.
*/
- *pd->port_rcvhdrtail_kvaddr = 0;
+ *(volatile u64 *)pd->port_rcvhdrtail_kvaddr = 0;
set_bit(INFINIPATH_R_PORTENABLE_SHIFT + pd->port_port,
&dd->ipath_rcvctrl);
} else
@@ -923,11 +932,11 @@ bail:
/* common code for the mappings on dma_alloc_coherent mem */
static int ipath_mmap_mem(struct vm_area_struct *vma,
- struct ipath_portdata *pd, unsigned len,
- int write_ok, dma_addr_t addr, char *what)
+ struct ipath_portdata *pd, unsigned len, int write_ok,
+ void *kvaddr, char *what)
{
struct ipath_devdata *dd = pd->port_dd;
- unsigned pfn = (unsigned long)addr >> PAGE_SHIFT;
+ unsigned long pfn;
int ret;
if ((vma->vm_end - vma->vm_start) > len) {
@@ -950,17 +959,17 @@ static int ipath_mmap_mem(struct vm_area_struct *vma,
vma->vm_flags &= ~VM_MAYWRITE;
}
+ pfn = virt_to_phys(kvaddr) >> PAGE_SHIFT;
ret = remap_pfn_range(vma, vma->vm_start, pfn,
len, vma->vm_page_prot);
if (ret)
- dev_info(&dd->pcidev->dev,
- "%s port%u mmap of %lx, %x bytes r%c failed: %d\n",
- what, pd->port_port, (unsigned long)addr, len,
- write_ok?'w':'o', ret);
+ dev_info(&dd->pcidev->dev, "%s port%u mmap of %lx, %x "
+ "bytes r%c failed: %d\n", what, pd->port_port,
+ pfn, len, write_ok?'w':'o', ret);
else
- ipath_cdbg(VERBOSE, "%s port%u mmaped %lx, %x bytes r%c\n",
- what, pd->port_port, (unsigned long)addr, len,
- write_ok?'w':'o');
+ ipath_cdbg(VERBOSE, "%s port%u mmaped %lx, %x bytes "
+ "r%c\n", what, pd->port_port, pfn, len,
+ write_ok?'w':'o');
bail:
return ret;
}
@@ -1049,7 +1058,7 @@ static int mmap_rcvegrbufs(struct vm_area_struct *vma,
struct ipath_devdata *dd = pd->port_dd;
unsigned long start, size;
size_t total_size, i;
- dma_addr_t *phys;
+ unsigned long pfn;
int ret;
size = pd->port_rcvegrbuf_size;
@@ -1073,11 +1082,11 @@ static int mmap_rcvegrbufs(struct vm_area_struct *vma,
vma->vm_flags &= ~VM_MAYWRITE;
start = vma->vm_start;
- phys = pd->port_rcvegrbuf_phys;
for (i = 0; i < pd->port_rcvegrbuf_chunks; i++, start += size) {
- ret = remap_pfn_range(vma, start, phys[i] >> PAGE_SHIFT,
- size, vma->vm_page_prot);
+ pfn = virt_to_phys(pd->port_rcvegrbuf[i]) >> PAGE_SHIFT;
+ ret = remap_pfn_range(vma, start, pfn, size,
+ vma->vm_page_prot);
if (ret < 0)
goto bail;
}
@@ -1290,7 +1299,7 @@ static int ipath_mmap(struct file *fp, struct vm_area_struct *vma)
else if (pgaddr == dd->ipath_pioavailregs_phys)
/* in-memory copy of pioavail registers */
ret = ipath_mmap_mem(vma, pd, PAGE_SIZE, 0,
- dd->ipath_pioavailregs_phys,
+ (void *) dd->ipath_pioavailregs_dma,
"pioavail registers");
else if (subport_fp(fp))
/* Subports don't mmap the physical receive buffers */
@@ -1304,12 +1313,12 @@ static int ipath_mmap(struct file *fp, struct vm_area_struct *vma)
* from an i/o perspective.
*/
ret = ipath_mmap_mem(vma, pd, pd->port_rcvhdrq_size, 1,
- pd->port_rcvhdrq_phys,
+ pd->port_rcvhdrq,
"rcvhdrq");
else if (pgaddr == (u64) pd->port_rcvhdrqtailaddr_phys)
/* in-memory copy of rcvhdrq tail register */
ret = ipath_mmap_mem(vma, pd, PAGE_SIZE, 0,
- pd->port_rcvhdrqtailaddr_phys,
+ pd->port_rcvhdrtail_kvaddr,
"rcvhdrq tail");
else
ret = -EINVAL;
@@ -1802,7 +1811,7 @@ static int ipath_do_user_init(struct file *fp,
* We explictly set the in-memory copy to 0 beforehand, so we don't
* have to wait to be sure the DMA update has happened.
*/
- *pd->port_rcvhdrtail_kvaddr = 0ULL;
+ *(volatile u64 *)pd->port_rcvhdrtail_kvaddr = 0ULL;
set_bit(INFINIPATH_R_PORTENABLE_SHIFT + pd->port_port,
&dd->ipath_rcvctrl);
ipath_write_kreg(dd, dd->ipath_kregs->kr_rcvctrl,
@@ -1832,6 +1841,8 @@ static void unlock_expected_tids(struct ipath_portdata *pd)
if (!dd->ipath_pageshadow[i])
continue;
+ pci_unmap_page(dd->pcidev, dd->ipath_physshadow[i],
+ PAGE_SIZE, PCI_DMA_FROMDEVICE);
ipath_release_user_pages_on_close(&dd->ipath_pageshadow[i],
1);
dd->ipath_pageshadow[i] = NULL;
@@ -1936,14 +1947,14 @@ static int ipath_close(struct inode *in, struct file *fp)
i = dd->ipath_pbufsport * (port - 1);
ipath_disarm_piobufs(dd, i, dd->ipath_pbufsport);
+ dd->ipath_f_clear_tids(dd, pd->port_port);
+
if (dd->ipath_pageshadow)
unlock_expected_tids(pd);
ipath_stats.sps_ports--;
ipath_cdbg(PROC, "%s[%u] closed port %u:%u\n",
pd->port_comm, pd->port_pid,
dd->ipath_unit, port);
-
- dd->ipath_f_clear_tids(dd, pd->port_port);
}
pd->port_pid = 0;
diff --git a/drivers/infiniband/hw/ipath/ipath_iba6120.c b/drivers/infiniband/hw/ipath/ipath_iba6120.c
index ac5cbe27c06..08a44dd9ed6 100644
--- a/drivers/infiniband/hw/ipath/ipath_iba6120.c
+++ b/drivers/infiniband/hw/ipath/ipath_iba6120.c
@@ -1113,7 +1113,7 @@ static void ipath_pe_put_tid_2(struct ipath_devdata *dd, u64 __iomem *tidptr,
if (pa != dd->ipath_tidinvalid) {
if (pa & ((1U << 11) - 1)) {
dev_info(&dd->pcidev->dev, "BUG: physaddr %lx "
- "not 4KB aligned!\n", pa);
+ "not 2KB aligned!\n", pa);
return;
}
pa >>= 11;
diff --git a/drivers/infiniband/hw/ipath/ipath_init_chip.c b/drivers/infiniband/hw/ipath/ipath_init_chip.c
index 44669dc2e22..d819cca524c 100644
--- a/drivers/infiniband/hw/ipath/ipath_init_chip.c
+++ b/drivers/infiniband/hw/ipath/ipath_init_chip.c
@@ -88,13 +88,13 @@ MODULE_PARM_DESC(kpiobufs, "Set number of PIO buffers for driver");
static int create_port0_egr(struct ipath_devdata *dd)
{
unsigned e, egrcnt;
- struct sk_buff **skbs;
+ struct ipath_skbinfo *skbinfo;
int ret;
egrcnt = dd->ipath_rcvegrcnt;
- skbs = vmalloc(sizeof(*dd->ipath_port0_skbs) * egrcnt);
- if (skbs == NULL) {
+ skbinfo = vmalloc(sizeof(*dd->ipath_port0_skbinfo) * egrcnt);
+ if (skbinfo == NULL) {
ipath_dev_err(dd, "allocation error for eager TID "
"skb array\n");
ret = -ENOMEM;
@@ -109,13 +109,13 @@ static int create_port0_egr(struct ipath_devdata *dd)
* 4 bytes so that the data buffer stays word aligned.
* See ipath_kreceive() for more details.
*/
- skbs[e] = ipath_alloc_skb(dd, GFP_KERNEL);
- if (!skbs[e]) {
+ skbinfo[e].skb = ipath_alloc_skb(dd, GFP_KERNEL);
+ if (!skbinfo[e].skb) {
ipath_dev_err(dd, "SKB allocation error for "
"eager TID %u\n", e);
while (e != 0)
- dev_kfree_skb(skbs[--e]);
- vfree(skbs);
+ dev_kfree_skb(skbinfo[--e].skb);
+ vfree(skbinfo);
ret = -ENOMEM;
goto bail;
}
@@ -124,14 +124,17 @@ static int create_port0_egr(struct ipath_devdata *dd)
* After loop above, so we can test non-NULL to see if ready
* to use at receive, etc.
*/
- dd->ipath_port0_skbs = skbs;
+ dd->ipath_port0_skbinfo = skbinfo;
for (e = 0; e < egrcnt; e++) {
- unsigned long phys =
- virt_to_phys(dd->ipath_port0_skbs[e]->data);
+ dd->ipath_port0_skbinfo[e].phys =
+ ipath_map_single(dd->pcidev,
+ dd->ipath_port0_skbinfo[e].skb->data,
+ dd->ipath_ibmaxlen, PCI_DMA_FROMDEVICE);
dd->ipath_f_put_tid(dd, e + (u64 __iomem *)
((char __iomem *) dd->ipath_kregbase +
- dd->ipath_rcvegrbase), 0, phys);
+ dd->ipath_rcvegrbase), 0,
+ dd->ipath_port0_skbinfo[e].phys);
}
ret = 0;
@@ -432,16 +435,33 @@ done:
*/
static void init_shadow_tids(struct ipath_devdata *dd)
{
- dd->ipath_pageshadow = (struct page **)
- vmalloc(dd->ipath_cfgports * dd->ipath_rcvtidcnt *
+ struct page **pages;
+ dma_addr_t *addrs;
+
+ pages = vmalloc(dd->ipath_cfgports * dd->ipath_rcvtidcnt *
sizeof(struct page *));
- if (!dd->ipath_pageshadow)
+ if (!pages) {
ipath_dev_err(dd, "failed to allocate shadow page * "
"array, no expected sends!\n");
- else
- memset(dd->ipath_pageshadow, 0,
- dd->ipath_cfgports * dd->ipath_rcvtidcnt *
- sizeof(struct page *));
+ dd->ipath_pageshadow = NULL;
+ return;
+ }
+
+ addrs = vmalloc(dd->ipath_cfgports * dd->ipath_rcvtidcnt *
+ sizeof(dma_addr_t));
+ if (!addrs) {
+ ipath_dev_err(dd, "failed to allocate shadow dma handle "
+ "array, no expected sends!\n");
+ vfree(dd->ipath_pageshadow);
+ dd->ipath_pageshadow = NULL;
+ return;
+ }
+
+ memset(pages, 0, dd->ipath_cfgports * dd->ipath_rcvtidcnt *
+ sizeof(struct page *));
+
+ dd->ipath_pageshadow = pages;
+ dd->ipath_physshadow = addrs;
}
static void enable_chip(struct ipath_devdata *dd,
diff --git a/drivers/infiniband/hw/ipath/ipath_intr.c b/drivers/infiniband/hw/ipath/ipath_intr.c
index 54b3dbc8195..f4d8aafc630 100644
--- a/drivers/infiniband/hw/ipath/ipath_intr.c
+++ b/drivers/infiniband/hw/ipath/ipath_intr.c
@@ -605,7 +605,7 @@ static int handle_errors(struct ipath_devdata *dd, ipath_err_t errs)
* don't report same point multiple times,
* except kernel
*/
- tl = (u32) * pd->port_rcvhdrtail_kvaddr;
+ tl = *(u64 *) pd->port_rcvhdrtail_kvaddr;
if (tl == dd->ipath_lastrcvhdrqtails[i])
continue;
hd = ipath_read_ureg32(dd, ur_rcvhdrhead,
diff --git a/drivers/infiniband/hw/ipath/ipath_kernel.h b/drivers/infiniband/hw/ipath/ipath_kernel.h
index 96e2bd8fb5f..2a0e9a43063 100644
--- a/drivers/infiniband/hw/ipath/ipath_kernel.h
+++ b/drivers/infiniband/hw/ipath/ipath_kernel.h
@@ -39,6 +39,8 @@
*/
#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/dma-mapping.h>
#include <asm/io.h>
#include "ipath_common.h"
@@ -62,7 +64,7 @@ struct ipath_portdata {
/* rcvhdrq base, needs mmap before useful */
void *port_rcvhdrq;
/* kernel virtual address where hdrqtail is updated */
- volatile __le64 *port_rcvhdrtail_kvaddr;
+ void *port_rcvhdrtail_kvaddr;
/*
* temp buffer for expected send setup, allocated at open, instead
* of each setup call
@@ -146,6 +148,11 @@ struct _ipath_layer {
void *l_arg;
};
+struct ipath_skbinfo {
+ struct sk_buff *skb;
+ dma_addr_t phys;
+};
+
struct ipath_devdata {
struct list_head ipath_list;
@@ -168,7 +175,7 @@ struct ipath_devdata {
/* ipath_cfgports pointers */
struct ipath_portdata **ipath_pd;
/* sk_buffs used by port 0 eager receive queue */
- struct sk_buff **ipath_port0_skbs;
+ struct ipath_skbinfo *ipath_port0_skbinfo;
/* kvirt address of 1st 2k pio buffer */
void __iomem *ipath_pio2kbase;
/* kvirt address of 1st 4k pio buffer */
@@ -335,6 +342,8 @@ struct ipath_devdata {
u64 *ipath_tidsimshadow;
/* shadow copy of struct page *'s for exp tid pages */
struct page **ipath_pageshadow;
+ /* shadow copy of dma handles for exp tid pages */
+ dma_addr_t *ipath_physshadow;
/* lock to workaround chip bug 9437 */
spinlock_t ipath_tid_lock;
@@ -865,6 +874,13 @@ int ipathfs_add_device(struct ipath_devdata *);
int ipathfs_remove_device(struct ipath_devdata *);
/*
+ * dma_addr wrappers - all 0's invalid for hw
+ */
+dma_addr_t ipath_map_page(struct pci_dev *, struct page *, unsigned long,
+ size_t, int);
+dma_addr_t ipath_map_single(struct pci_dev *, void *, size_t, int);
+
+/*
* Flush write combining store buffers (if present) and perform a write
* barrier.
*/
diff --git a/drivers/infiniband/hw/ipath/ipath_user_pages.c b/drivers/infiniband/hw/ipath/ipath_user_pages.c
index e32fca9faf8..413754b1d8a 100644
--- a/drivers/infiniband/hw/ipath/ipath_user_pages.c
+++ b/drivers/infiniband/hw/ipath/ipath_user_pages.c
@@ -90,6 +90,62 @@ bail:
}
/**
+ * ipath_map_page - a safety wrapper around pci_map_page()
+ *
+ * A dma_addr of all 0's is interpreted by the chip as "disabled".
+ * Unfortunately, it can also be a valid dma_addr returned on some
+ * architectures.
+ *
+ * The powerpc iommu assigns dma_addrs in ascending order, so we don't
+ * have to bother with retries or mapping a dummy page to insure we
+ * don't just get the same mapping again.
+ *
+ * I'm sure we won't be so lucky with other iommu's, so FIXME.
+ */
+dma_addr_t ipath_map_page(struct pci_dev *hwdev, struct page *page,
+ unsigned long offset, size_t size, int direction)
+{
+ dma_addr_t phys;
+
+ phys = pci_map_page(hwdev, page, offset, size, direction);
+
+ if (phys == 0) {
+ pci_unmap_page(hwdev, phys, size, direction);
+ phys = pci_map_page(hwdev, page, offset, size, direction);
+ /*
+ * FIXME: If we get 0 again, we should keep this page,
+ * map another, then free the 0 page.
+ */
+ }
+
+ return phys;
+}
+
+/**
+ * ipath_map_single - a safety wrapper around pci_map_single()
+ *
+ * Same idea as ipath_map_page().
+ */
+dma_addr_t ipath_map_single(struct pci_dev *hwdev, void *ptr, size_t size,
+ int direction)
+{
+ dma_addr_t phys;
+
+ phys = pci_map_single(hwdev, ptr, size, direction);
+
+ if (phys == 0) {
+ pci_unmap_single(hwdev, phys, size, direction);
+ phys = pci_map_single(hwdev, ptr, size, direction);
+ /*
+ * FIXME: If we get 0 again, we should keep this page,
+ * map another, then free the 0 page.
+ */
+ }
+
+ return phys;
+}
+
+/**
* ipath_get_user_pages - lock user pages into memory
* @start_page: the start page
* @num_pages: the number of pages
diff --git a/drivers/infiniband/hw/ipath/ipath_wc_ppc64.c b/drivers/infiniband/hw/ipath/ipath_wc_ppc64.c
index 036fde662aa..0095bb70f34 100644
--- a/drivers/infiniband/hw/ipath/ipath_wc_ppc64.c
+++ b/drivers/infiniband/hw/ipath/ipath_wc_ppc64.c
@@ -38,13 +38,23 @@
#include "ipath_kernel.h"
/**
- * ipath_unordered_wc - indicate whether write combining is ordered
+ * ipath_enable_wc - enable write combining for MMIO writes to the device
+ * @dd: infinipath device
*
- * PowerPC systems (at least those in the 970 processor family)
- * write partially filled store buffers in address order, but will write
- * completely filled store buffers in "random" order, and therefore must
- * have serialization for correctness with current InfiniPath chips.
+ * Nothing to do on PowerPC, so just return without error.
+ */
+int ipath_enable_wc(struct ipath_devdata *dd)
+{
+ return 0;
+}
+
+/**
+ * ipath_unordered_wc - indicate whether write combining is unordered
*
+ * Because our performance depends on our ability to do write
+ * combining mmio writes in the most efficient way, we need to
+ * know if we are on a processor that may reorder stores when
+ * write combining.
*/
int ipath_unordered_wc(void)
{