diff options
author | Alexander Graf <agraf@suse.de> | 2011-12-09 14:44:13 +0100 |
---|---|---|
committer | Avi Kivity <avi@redhat.com> | 2012-03-05 14:52:30 +0200 |
commit | 468a12c2b53776721ff83517d4a195b85c5fce54 (patch) | |
tree | ba417210997c2e3119525641764303d97db32815 /arch/powerpc/kvm/book3s_64_mmu_host.c | |
parent | d33ad328c0025c45f4688a769aeebddc342222c1 (diff) | |
download | linux-468a12c2b53776721ff83517d4a195b85c5fce54.tar.bz2 |
KVM: PPC: Use get/set for to_svcpu to help preemption
When running the 64-bit Book3s PR code without CONFIG_PREEMPT_NONE, we were
doing a few things wrong, most notably access to PACA fields without making
sure that the pointers stay stable accross the access (preempt_disable()).
This patch moves to_svcpu towards a get/put model which allows us to disable
preemption while accessing the shadow vcpu fields in the PACA. That way we
can run preemptible and everyone's happy!
Reported-by: Jörg Sommer <joerg@alea.gnuu.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_host.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_host.c | 66 |
1 files changed, 43 insertions, 23 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c index fa2f08434ba5..6f87f39a1ac2 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_host.c +++ b/arch/powerpc/kvm/book3s_64_mmu_host.c @@ -88,12 +88,14 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte) int vflags = 0; int attempt = 0; struct kvmppc_sid_map *map; + int r = 0; /* Get host physical address for gpa */ hpaddr = kvmppc_gfn_to_pfn(vcpu, orig_pte->raddr >> PAGE_SHIFT); if (is_error_pfn(hpaddr)) { printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n", orig_pte->eaddr); - return -EINVAL; + r = -EINVAL; + goto out; } hpaddr <<= PAGE_SHIFT; hpaddr |= orig_pte->raddr & (~0xfffULL & ~PAGE_MASK); @@ -110,7 +112,8 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte) printk(KERN_ERR "KVM: Segment map for 0x%llx (0x%lx) failed\n", vsid, orig_pte->eaddr); WARN_ON(true); - return -EINVAL; + r = -EINVAL; + goto out; } vsid = map->host_vsid; @@ -131,8 +134,10 @@ map_again: /* In case we tried normal mapping already, let's nuke old entries */ if (attempt > 1) - if (ppc_md.hpte_remove(hpteg) < 0) - return -1; + if (ppc_md.hpte_remove(hpteg) < 0) { + r = -1; + goto out; + } ret = ppc_md.hpte_insert(hpteg, va, hpaddr, rflags, vflags, MMU_PAGE_4K, MMU_SEGSIZE_256M); @@ -162,7 +167,8 @@ map_again: kvmppc_mmu_hpte_cache_map(vcpu, pte); } - return 0; +out: + return r; } static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid) @@ -207,25 +213,30 @@ static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid) static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid) { + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); int i; int max_slb_size = 64; int found_inval = -1; int r; - if (!to_svcpu(vcpu)->slb_max) - to_svcpu(vcpu)->slb_max = 1; + if (!svcpu->slb_max) + svcpu->slb_max = 1; /* Are we overwriting? */ - for (i = 1; i < to_svcpu(vcpu)->slb_max; i++) { - if (!(to_svcpu(vcpu)->slb[i].esid & SLB_ESID_V)) + for (i = 1; i < svcpu->slb_max; i++) { + if (!(svcpu->slb[i].esid & SLB_ESID_V)) found_inval = i; - else if ((to_svcpu(vcpu)->slb[i].esid & ESID_MASK) == esid) - return i; + else if ((svcpu->slb[i].esid & ESID_MASK) == esid) { + r = i; + goto out; + } } /* Found a spare entry that was invalidated before */ - if (found_inval > 0) - return found_inval; + if (found_inval > 0) { + r = found_inval; + goto out; + } /* No spare invalid entry, so create one */ @@ -233,30 +244,35 @@ static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid) max_slb_size = mmu_slb_size; /* Overflowing -> purge */ - if ((to_svcpu(vcpu)->slb_max) == max_slb_size) + if ((svcpu->slb_max) == max_slb_size) kvmppc_mmu_flush_segments(vcpu); - r = to_svcpu(vcpu)->slb_max; - to_svcpu(vcpu)->slb_max++; + r = svcpu->slb_max; + svcpu->slb_max++; +out: + svcpu_put(svcpu); return r; } int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr) { + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); u64 esid = eaddr >> SID_SHIFT; u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V; u64 slb_vsid = SLB_VSID_USER; u64 gvsid; int slb_index; struct kvmppc_sid_map *map; + int r = 0; slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK); if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) { /* Invalidate an entry */ - to_svcpu(vcpu)->slb[slb_index].esid = 0; - return -ENOENT; + svcpu->slb[slb_index].esid = 0; + r = -ENOENT; + goto out; } map = find_sid_vsid(vcpu, gvsid); @@ -269,18 +285,22 @@ int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr) slb_vsid &= ~SLB_VSID_KP; slb_esid |= slb_index; - to_svcpu(vcpu)->slb[slb_index].esid = slb_esid; - to_svcpu(vcpu)->slb[slb_index].vsid = slb_vsid; + svcpu->slb[slb_index].esid = slb_esid; + svcpu->slb[slb_index].vsid = slb_vsid; trace_kvm_book3s_slbmte(slb_vsid, slb_esid); - return 0; +out: + svcpu_put(svcpu); + return r; } void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu) { - to_svcpu(vcpu)->slb_max = 1; - to_svcpu(vcpu)->slb[0].esid = 0; + struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu); + svcpu->slb_max = 1; + svcpu->slb[0].esid = 0; + svcpu_put(svcpu); } void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu) |