1 files changed, 36 insertions, 17 deletions

diff --git a/arch/powerpc/kvm/44x_tlb.c b/arch/powerpc/kvm/44x_tlb.c
index 5a5602da5091..2e227a412bc2 100644
--- a/arch/powerpc/kvm/44x_tlb.c
+++ b/arch/powerpc/kvm/44x_tlb.c
@@ -19,6 +19,7 @@
 
 #include <linux/types.h>
 #include <linux/string.h>
+#include <linux/kvm.h>
 #include <linux/kvm_host.h>
 #include <linux/highmem.h>
 #include <asm/mmu-44x.h>
@@ -109,7 +110,6 @@ static int kvmppc_44x_tlbe_is_writable(struct tlbe *tlbe)
         return tlbe->word2 & (PPC44x_TLB_SW|PPC44x_TLB_UW);
 }
 
-/* Must be called with mmap_sem locked for writing. */
 static void kvmppc_44x_shadow_release(struct kvm_vcpu *vcpu,
                                       unsigned int index)
 {
@@ -124,6 +124,11 @@ static void kvmppc_44x_shadow_release(struct kvm_vcpu *vcpu,
         }
 }
 
+void kvmppc_tlbe_set_modified(struct kvm_vcpu *vcpu, unsigned int i)
+{
+    vcpu->arch.shadow_tlb_mod[i] = 1;
+}
+
 /* Caller must ensure that the specified guest TLB entry is safe to insert into
  * the shadow TLB. */
 void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid,
@@ -142,19 +147,16 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid,
         stlbe = &vcpu->arch.shadow_tlb[victim];
 
         /* Get reference to new page. */
-        down_read(&current->mm->mmap_sem);
         new_page = gfn_to_page(vcpu->kvm, gfn);
         if (is_error_page(new_page)) {
                 printk(KERN_ERR "Couldn't get guest page for gfn %lx!\n", gfn);
                 kvm_release_page_clean(new_page);
-                up_read(&current->mm->mmap_sem);
                 return;
         }
         hpaddr = page_to_phys(new_page);
 
         /* Drop reference to old page. */
         kvmppc_44x_shadow_release(vcpu, victim);
-        up_read(&current->mm->mmap_sem);
 
         vcpu->arch.shadow_pages[victim] = new_page;
 
@@ -164,27 +166,30 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid,
 
         /* XXX what about AS? */
 
-        stlbe->tid = asid & 0xff;
+        stlbe->tid = !(asid & 0xff);
 
         /* Force TS=1 for all guest mappings. */
         /* For now we hardcode 4KB mappings, but it will be important to
          * use host large pages in the future. */
         stlbe->word0 = (gvaddr & PAGE_MASK) | PPC44x_TLB_VALID | PPC44x_TLB_TS
                        | PPC44x_TLB_4K;
-
         stlbe->word1 = (hpaddr & 0xfffffc00) | ((hpaddr >> 32) & 0xf);
         stlbe->word2 = kvmppc_44x_tlb_shadow_attrib(flags,
                                                     vcpu->arch.msr & MSR_PR);
+        kvmppc_tlbe_set_modified(vcpu, victim);
+
+        KVMTRACE_5D(STLB_WRITE, vcpu, victim,
+                        stlbe->tid, stlbe->word0, stlbe->word1, stlbe->word2,
+                        handler);
 }
 
 void kvmppc_mmu_invalidate(struct kvm_vcpu *vcpu, gva_t eaddr,
                            gva_t eend, u32 asid)
 {
-        unsigned int pid = asid & 0xff;
+        unsigned int pid = !(asid & 0xff);
         int i;
 
         /* XXX Replace loop with fancy data structures. */
-        down_write(&current->mm->mmap_sem);
         for (i = 0; i <= tlb_44x_hwater; i++) {
                 struct tlbe *stlbe = &vcpu->arch.shadow_tlb[i];
                 unsigned int tid;
@@ -204,21 +209,35 @@ void kvmppc_mmu_invalidate(struct kvm_vcpu *vcpu, gva_t eaddr,
 
                 kvmppc_44x_shadow_release(vcpu, i);
                 stlbe->word0 = 0;
+                kvmppc_tlbe_set_modified(vcpu, i);
+                KVMTRACE_5D(STLB_INVAL, vcpu, i,
+                                stlbe->tid, stlbe->word0, stlbe->word1,
+                                stlbe->word2, handler);
         }
-        up_write(&current->mm->mmap_sem);
 }
 
-/* Invalidate all mappings, so that when they fault back in they will get the
- * proper permission bits. */
+/* Invalidate all mappings on the privilege switch after PID has been changed.
+ * The guest always runs with PID=1, so we must clear the entire TLB when
+ * switching address spaces. */
 void kvmppc_mmu_priv_switch(struct kvm_vcpu *vcpu, int usermode)
 {
         int i;
 
-        /* XXX Replace loop with fancy data structures. */
-        down_write(&current->mm->mmap_sem);
-        for (i = 0; i <= tlb_44x_hwater; i++) {
-                kvmppc_44x_shadow_release(vcpu, i);
-                vcpu->arch.shadow_tlb[i].word0 = 0;
+        if (vcpu->arch.swap_pid) {
+                /* XXX Replace loop with fancy data structures. */
+                for (i = 0; i <= tlb_44x_hwater; i++) {
+                        struct tlbe *stlbe = &vcpu->arch.shadow_tlb[i];
+
+                        /* Future optimization: clear only userspace mappings. */
+                        kvmppc_44x_shadow_release(vcpu, i);
+                        stlbe->word0 = 0;
+                        kvmppc_tlbe_set_modified(vcpu, i);
+                        KVMTRACE_5D(STLB_INVAL, vcpu, i,
+                                    stlbe->tid, stlbe->word0, stlbe->word1,
+                                    stlbe->word2, handler);
+                }
+                vcpu->arch.swap_pid = 0;
         }
-        up_write(&current->mm->mmap_sem);
+
+        vcpu->arch.shadow_pid = !usermode;
 }