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Subject[PATCH 2/2] arm:kvm remove len 8 for mmio read write buf
Date
For arm 32 bit architecture, 8 bytes load/store operation in one instruction
will not be generated by compiler.

And before invoke mmio_read_buf, there is a piece of code:
"
len = run->mmio.len;
if (len > sizeof(unsigned long))
return -EINVAL;

data = mmio_read_buf(run->mmio.data, len);
"

This piece code also tells that len variable does not exceeds 4 bytes.
So, remove 8 bytes assign in mmio_read_buf and mmio_write_buf.

Signed-off-by: Peng Fan <van.freenix@gmail.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Christoffer Dall <christoffer.dall@linaro.org>
CC: Marc Zyngier <marc.zyngier@arm.com>
CC: Russell King <linux@arm.linux.org.uk>
---
arch/arm/kvm/mmio.c | 10 ----------
1 file changed, 10 deletions(-)

diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c
index 4cb5a93..953a819 100644
--- a/arch/arm/kvm/mmio.c
+++ b/arch/arm/kvm/mmio.c
@@ -30,7 +30,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data)
u8 byte;
u16 hword;
u32 word;
- u64 dword;
} tmp;

switch (len) {
@@ -46,10 +45,6 @@ static void mmio_write_buf(char *buf, unsigned int len, unsigned long data)
tmp.word = data;
datap = &tmp.word;
break;
- case 8:
- tmp.dword = data;
- datap = &tmp.dword;
- break;
}

memcpy(buf, datap, len);
@@ -61,7 +56,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len)
union {
u16 hword;
u32 word;
- u64 dword;
} tmp;

switch (len) {
@@ -76,10 +70,6 @@ static unsigned long mmio_read_buf(char *buf, unsigned int len)
memcpy(&tmp.word, buf, len);
data = tmp.word;
break;
- case 8:
- memcpy(&tmp.dword, buf, len);
- data = tmp.dword;
- break;
}

return data;
--
1.8.4


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