[PATCH] ntb: perf test: fix address space confusion

From: Arnd Bergmann
Date: Tue Jan 26 2016 - 04:33:06 EST


The ntb driver assigns between pointers an __iomem tokens, and
also casts them to 64-bit integers, which results in compiler
warnings on 32-bit systems:

drivers/ntb/test/ntb_perf.c: In function 'perf_copy':
drivers/ntb/test/ntb_perf.c:213:10: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
vbase = (u64)(u64 *)mw->vbase;
^
drivers/ntb/test/ntb_perf.c:214:14: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
dst_vaddr = (u64)(u64 *)dst;
^

This adds __iomem annotations where needed and changes the temporary
variables to iomem pointers to avoid casting them to u64. I did not
see the problem in linux-next earlier, but it show showed up in
4.5-rc1.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Fixes: 8a7b6a778a85 ("ntb: ntb perf tool")
---
drivers/ntb/test/ntb_perf.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/ntb/test/ntb_perf.c b/drivers/ntb/test/ntb_perf.c
index c8a37ba4b4f9..6bdc1e7b7503 100644
--- a/drivers/ntb/test/ntb_perf.c
+++ b/drivers/ntb/test/ntb_perf.c
@@ -178,7 +178,7 @@ static void perf_copy_callback(void *data)
atomic_dec(&pctx->dma_sync);
}

-static ssize_t perf_copy(struct pthr_ctx *pctx, char *dst,
+static ssize_t perf_copy(struct pthr_ctx *pctx, char __iomem *dst,
char *src, size_t size)
{
struct perf_ctx *perf = pctx->perf;
@@ -189,7 +189,8 @@ static ssize_t perf_copy(struct pthr_ctx *pctx, char *dst,
dma_cookie_t cookie;
size_t src_off, dst_off;
struct perf_mw *mw = &perf->mw;
- u64 vbase, dst_vaddr;
+ void __iomem *vbase;
+ void __iomem *dst_vaddr;
dma_addr_t dst_phys;
int retries = 0;

@@ -204,14 +205,14 @@ static ssize_t perf_copy(struct pthr_ctx *pctx, char *dst,
}

device = chan->device;
- src_off = (size_t)src & ~PAGE_MASK;
- dst_off = (size_t)dst & ~PAGE_MASK;
+ src_off = (uintptr_t)src & ~PAGE_MASK;
+ dst_off = (uintptr_t __force)dst & ~PAGE_MASK;

if (!is_dma_copy_aligned(device, src_off, dst_off, size))
return -ENODEV;

- vbase = (u64)(u64 *)mw->vbase;
- dst_vaddr = (u64)(u64 *)dst;
+ vbase = mw->vbase;
+ dst_vaddr = dst;
dst_phys = mw->phys_addr + (dst_vaddr - vbase);

unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOWAIT);
@@ -261,13 +262,13 @@ err_get_unmap:
return 0;
}

-static int perf_move_data(struct pthr_ctx *pctx, char *dst, char *src,
+static int perf_move_data(struct pthr_ctx *pctx, char __iomem *dst, char *src,
u64 buf_size, u64 win_size, u64 total)
{
int chunks, total_chunks, i;
int copied_chunks = 0;
u64 copied = 0, result;
- char *tmp = dst;
+ char __iomem *tmp = dst;
u64 perf, diff_us;
ktime_t kstart, kstop, kdiff;

@@ -324,7 +325,7 @@ static int ntb_perf_thread(void *data)
struct perf_ctx *perf = pctx->perf;
struct pci_dev *pdev = perf->ntb->pdev;
struct perf_mw *mw = &perf->mw;
- char *dst;
+ char __iomem *dst;
u64 win_size, buf_size, total;
void *src;
int rc, node, i;
@@ -364,7 +365,7 @@ static int ntb_perf_thread(void *data)
if (buf_size > MAX_TEST_SIZE)
buf_size = MAX_TEST_SIZE;

- dst = (char *)mw->vbase;
+ dst = (char __iomem *)mw->vbase;

atomic_inc(&perf->tsync);
while (atomic_read(&perf->tsync) != perf->perf_threads)
--
2.7.0