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

[Arnd Bergmann]

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 <ar...@arndb.de>
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

[Jiang, Dave]

On Tue, 2016-01-26 at 10:31 +0100, Arnd Bergmann wrote:
> 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 <ar...@arndb.de>

Acked-by: Dave Jiang <dave....@intel.com>

[Jon Mason]

On Tue, Jan 26, 2016 at 1:20 PM, Jiang, Dave <dave....@intel.com> wrote:
> On Tue, 2016-01-26 at 10:31 +0100, Arnd Bergmann wrote:
>> 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 <ar...@arndb.de>
>
> Acked-by: Dave Jiang <dave....@intel.com>

Sorry for the delay. Applied.

Thanks,
Jon

> --
> You received this message because you are subscribed to the Google Groups "linux-ntb" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to linux-ntb+...@googlegroups.com.
> To post to this group, send email to linu...@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/linux-ntb/1453832409.3824.59.camel%40intel.com.
> For more options, visit https://groups.google.com/d/optout.