[PATCH] nvme: fix 32-bit build warning

From: Arnd Bergmann
Date: Tue Oct 06 2015 - 16:29:48 EST


Compiling the nvme driver on 32-bit warns about a cast from a __u64
variable to a pointer:

drivers/block/nvme-core.c: In function 'nvme_submit_io':
drivers/block/nvme-core.c:1847:4: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
(void __user *)io.addr, length, NULL, 0);

The cast here is intentional and safe, so we can shut up the
gcc warning by adding an intermediate cast to 'uintptr_t'.

I had previously submitted a patch to fix this problem in the
nvme driver, but it was accepted on the same day that two new
warnings got added.

For clarification, I also change the third instance of this cast
to use uintptr_t instead of unsigned long now.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Fixes: d29ec8241c10e ("nvme: submit internal commands through the block layer")
---
v2: use uintptr_t for intermediate cast

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index e917cf304ad0..e8ff16c63977 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -1804,7 +1804,7 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)

length = (io.nblocks + 1) << ns->lba_shift;
meta_len = (io.nblocks + 1) * ns->ms;
- metadata = (void __user *)(unsigned long)io.metadata;
+ metadata = (void __user *)(uintptr_t)io.metadata;
write = io.opcode & 1;

if (ns->ext) {
@@ -1844,7 +1844,7 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
c.rw.metadata = cpu_to_le64(meta_dma);

status = __nvme_submit_sync_cmd(ns->queue, &c, NULL,
- (void __user *)io.addr, length, NULL, 0);
+ (void __user *)(uintptr_t)io.addr, length, NULL, 0);
unmap:
if (meta) {
if (status == NVME_SC_SUCCESS && !write) {
@@ -1886,7 +1886,7 @@ static int nvme_user_cmd(struct nvme_dev *dev, struct nvme_ns *ns,
timeout = msecs_to_jiffies(cmd.timeout_ms);

status = __nvme_submit_sync_cmd(ns ? ns->queue : dev->admin_q, &c,
- NULL, (void __user *)cmd.addr, cmd.data_len,
+ NULL, (void __user *)(uintptr_t)cmd.addr, cmd.data_len,
&cmd.result, timeout);
if (status >= 0) {
if (put_user(cmd.result, &ucmd->result))

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