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Subject[PATCH 1/5] KVM: SVM: Move msrpm offset calculation to seperate function
Date
The algorithm to find the offset in the msrpm for a given
msr is needed at other places too. Move that logic to its
own function.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
arch/x86/kvm/svm.c | 53 ++++++++++++++++++++++++++++++++++++---------------
1 files changed, 37 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index df6f491..d8d4e35 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -198,6 +198,28 @@ static u32 msrpm_ranges[] = {0, 0xc0000000, 0xc0010000};
#define NUM_MSR_MAPS ARRAY_SIZE(msrpm_ranges)
#define MSRS_RANGE_SIZE 2048
#define MSRS_IN_RANGE (MSRS_RANGE_SIZE * 8 / 2)
+#define MSR_INVALID 0xffffffff
+
+static u32 svm_msrpm_offset(u32 msr)
+{
+ u32 offset;
+ int i;
+
+ for (i = 0; i < NUM_MSR_MAPS; i++) {
+ if (msr < msrpm_ranges[i] ||
+ msr >= msrpm_ranges[i] + MSRS_IN_RANGE)
+ continue;
+
+ offset = (msr - msrpm_ranges[i]) / 4; /* 4 msrs per u8 */
+ offset += (i * MSRS_RANGE_SIZE); /* add range offset */
+
+ /* Now we have the u8 offset - but need the u32 offset */
+ return offset / 4;
+ }
+
+ /* MSR not in any range */
+ return MSR_INVALID;
+}

#define MAX_INST_SIZE 15

@@ -417,23 +439,22 @@ err_1:
static void set_msr_interception(u32 *msrpm, unsigned msr,
int read, int write)
{
- int i;
+ u8 bit_read, bit_write;
+ unsigned long tmp;
+ u32 offset;

- for (i = 0; i < NUM_MSR_MAPS; i++) {
- if (msr >= msrpm_ranges[i] &&
- msr < msrpm_ranges[i] + MSRS_IN_RANGE) {
- u32 msr_offset = (i * MSRS_IN_RANGE + msr -
- msrpm_ranges[i]) * 2;
-
- u32 *base = msrpm + (msr_offset / 32);
- u32 msr_shift = msr_offset % 32;
- u32 mask = ((write) ? 0 : 2) | ((read) ? 0 : 1);
- *base = (*base & ~(0x3 << msr_shift)) |
- (mask << msr_shift);
- return;
- }
- }
- BUG();
+ offset = svm_msrpm_offset(msr);
+ bit_read = 2 * (msr & 0x0f);
+ bit_write = 2 * (msr & 0x0f) + 1;
+
+ BUG_ON(offset == MSR_INVALID);
+
+ tmp = msrpm[offset];
+
+ read ? clear_bit(bit_read, &tmp) : set_bit(bit_read, &tmp);
+ write ? clear_bit(bit_write, &tmp) : set_bit(bit_write, &tmp);
+
+ msrpm[offset] = tmp;
}

static void svm_vcpu_init_msrpm(u32 *msrpm)
--
1.7.0



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