From 455716fa941ec7a03c04bd54e1b906698171b15c Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Mon, 1 Mar 2010 15:34:35 +0100 Subject: [PATCH] KVM: SVM: Move msrpm offset calculation to seperate function 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 Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/svm.c | 53 ++++++++++++++++++++++++++++++++-------------- 1 file changed, 37 insertions(+), 16 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 07437ca12787..429a24435c6d 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -117,6 +117,8 @@ struct vcpu_svm { unsigned long int3_rip; }; +#define MSR_INVALID 0xffffffffU + /* enable NPT for AMD64 and X86 with PAE */ #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE) static bool npt_enabled = true; @@ -200,6 +202,27 @@ static u32 msrpm_ranges[] = {0, 0xc0000000, 0xc0010000}; #define MSRS_RANGE_SIZE 2048 #define MSRS_IN_RANGE (MSRS_RANGE_SIZE * 8 / 2) +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 static inline u32 svm_has(u32 feat) @@ -418,23 +441,21 @@ 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; + tmp = msrpm[offset]; + + BUG_ON(offset == MSR_INVALID); + + 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) -- 2.39.5