lib/bitmap.c: quiet sparse noise about address space

From: H Hartley Sweeten
Date: Wed Aug 31 2011 - 21:14:09 EST


The functions __bitmap_parse and __bitmap_parselist both take a pointer
to a kernel buffer as a parameter and then cast it to a pointer to user
buffer for use in cases when the parameter is_user indicates that the
buffer is actually located in user space. This casting, and the casts
in the callers, results in sparse noise like the following:

warning: incorrect type in initializer (different address spaces)
expected char const [noderef] <asn:1>*ubuf
got char const *buf
warning: cast removes address space of expression

Since these casts are intentional, use __force to quiet the noise.

Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Len Brown <len.brown@xxxxxxxxx>
Cc: Huang Ying <ying.huang@xxxxxxxxx>
Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>

---

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 2f4412e..b7b71bd 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -419,7 +419,7 @@ int __bitmap_parse(const char *buf, unsigned int buflen,
{
int c, old_c, totaldigits, ndigits, nchunks, nbits;
u32 chunk;
- const char __user *ubuf = buf;
+ const char __user __force *ubuf = buf;

bitmap_zero(maskp, nmaskbits);

@@ -504,7 +504,9 @@ int bitmap_parse_user(const char __user *ubuf,
{
if (!access_ok(VERIFY_READ, ubuf, ulen))
return -EFAULT;
- return __bitmap_parse((const char *)ubuf, ulen, 1, maskp, nmaskbits);
+ return __bitmap_parse((const char __force *)ubuf,
+ ulen, 1, maskp, nmaskbits);
+
}
EXPORT_SYMBOL(bitmap_parse_user);

@@ -594,7 +596,7 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
{
unsigned a, b;
int c, old_c, totaldigits;
- const char __user *ubuf = buf;
+ const char __user __force *ubuf = buf;
int exp_digit, in_range;

totaldigits = c = 0;
@@ -694,7 +696,7 @@ int bitmap_parselist_user(const char __user *ubuf,
{
if (!access_ok(VERIFY_READ, ubuf, ulen))
return -EFAULT;
- return __bitmap_parselist((const char *)ubuf,
+ return __bitmap_parselist((const char __force *)ubuf,
ulen, 1, maskp, nmaskbits);
}
EXPORT_SYMBOL(bitmap_parselist_user);
--
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