| Message ID | 1455501309-47200-3-git-send-email-aik@ozlabs.ru |
|---|---|
| State | Accepted |
| Headers | show |
On Mon, Feb 15, 2016 at 12:55:04PM +1100, Alexey Kardashevskiy wrote: > This reworks the existing H_PUT_TCE/H_GET_TCE handlers to have following > patches applied nicer. > > This moves the ioba boundaries check to a helper and adds a check for > least bits which have to be zeros. > > The patch is pretty mechanical (only check for least ioba bits is added) > so no change in behaviour is expected. > > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> > --- > Changelog: > v3: > * moved list_for_each_entry_lockless() to the next patch > * added overflow check in kvmppc_ioba_validate() as H_STUFF_TCE handles > more than just 512 TCEs at once > > v2: > * compare @ret with H_SUCCESS instead of assuming H_SUCCESS is zero > * made error reporting cleaner > --- > arch/powerpc/kvm/book3s_64_vio_hv.c | 109 +++++++++++++++++++++++------------- > 1 file changed, 71 insertions(+), 38 deletions(-) > > diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c > index 89e96b3..f29ba2c 100644 > --- a/arch/powerpc/kvm/book3s_64_vio_hv.c > +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c > @@ -35,71 +35,104 @@ > #include <asm/ppc-opcode.h> > #include <asm/kvm_host.h> > #include <asm/udbg.h> > +#include <asm/iommu.h> > > #define TCES_PER_PAGE (PAGE_SIZE / sizeof(u64)) > > +/* > + * Finds a TCE table descriptor by LIOBN. > + * > + * WARNING: This will be called in real or virtual mode on HV KVM and virtual > + * mode on PR KVM > + */ > +static struct kvmppc_spapr_tce_table *kvmppc_find_table(struct kvm_vcpu *vcpu, > + unsigned long liobn) > +{ > + struct kvm *kvm = vcpu->kvm; > + struct kvmppc_spapr_tce_table *stt; > + > + list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) > + if (stt->liobn == liobn) > + return stt; > + > + return NULL; > +} > + > +/* > + * Validates IO address. > + * > + * WARNING: This will be called in real-mode on HV KVM and virtual > + * mode on PR KVM > + */ > +static long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt, > + unsigned long ioba, unsigned long npages) > +{ > + unsigned long mask = (1ULL << IOMMU_PAGE_SHIFT_4K) - 1; > + unsigned long idx = ioba >> IOMMU_PAGE_SHIFT_4K; > + unsigned long size = stt->window_size >> IOMMU_PAGE_SHIFT_4K; > + > + if ((ioba & mask) || (idx + npages > size) || (idx + npages < idx)) > + return H_PARAMETER; > + > + return H_SUCCESS; > +} > + > /* WARNING: This will be called in real-mode on HV KVM and virtual > * mode on PR KVM > */ > long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, > unsigned long ioba, unsigned long tce) > { > - struct kvm *kvm = vcpu->kvm; > - struct kvmppc_spapr_tce_table *stt; > + struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn); > + long ret; > + unsigned long idx; > + struct page *page; > + u64 *tbl; > > /* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */ > /* liobn, ioba, tce); */ > > - list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) { > - if (stt->liobn == liobn) { > - unsigned long idx = ioba >> SPAPR_TCE_SHIFT; > - struct page *page; > - u64 *tbl; > + if (!stt) > + return H_TOO_HARD; > > - /* udbg_printf("H_PUT_TCE: liobn 0x%lx => stt=%p window_size=0x%x\n", */ > - /* liobn, stt, stt->window_size); */ > - if (ioba >= stt->window_size) > - return H_PARAMETER; > + ret = kvmppc_ioba_validate(stt, ioba, 1); > + if (ret != H_SUCCESS) > + return ret; > > - page = stt->pages[idx / TCES_PER_PAGE]; > - tbl = (u64 *)page_address(page); > + idx = ioba >> SPAPR_TCE_SHIFT; > + page = stt->pages[idx / TCES_PER_PAGE]; > + tbl = (u64 *)page_address(page); > > - /* FIXME: Need to validate the TCE itself */ > - /* udbg_printf("tce @ %p\n", &tbl[idx % TCES_PER_PAGE]); */ > - tbl[idx % TCES_PER_PAGE] = tce; > - return H_SUCCESS; > - } > - } > + /* FIXME: Need to validate the TCE itself */ > + /* udbg_printf("tce @ %p\n", &tbl[idx % TCES_PER_PAGE]); */ > + tbl[idx % TCES_PER_PAGE] = tce; > > - /* Didn't find the liobn, punt it to userspace */ > - return H_TOO_HARD; > + return H_SUCCESS; > } > EXPORT_SYMBOL_GPL(kvmppc_h_put_tce); > > long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn, > unsigned long ioba) > { > - struct kvm *kvm = vcpu->kvm; > - struct kvmppc_spapr_tce_table *stt; > + struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn); > + long ret; > + unsigned long idx; > + struct page *page; > + u64 *tbl; > > - list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) { > - if (stt->liobn == liobn) { > - unsigned long idx = ioba >> SPAPR_TCE_SHIFT; > - struct page *page; > - u64 *tbl; > + if (!stt) > + return H_TOO_HARD; > > - if (ioba >= stt->window_size) > - return H_PARAMETER; > + ret = kvmppc_ioba_validate(stt, ioba, 1); > + if (ret != H_SUCCESS) > + return ret; > > - page = stt->pages[idx / TCES_PER_PAGE]; > - tbl = (u64 *)page_address(page); > + idx = ioba >> SPAPR_TCE_SHIFT; > + page = stt->pages[idx / TCES_PER_PAGE]; > + tbl = (u64 *)page_address(page); > > - vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; > - return H_SUCCESS; > - } > - } > + vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; > > - /* Didn't find the liobn, punt it to userspace */ > - return H_TOO_HARD; > + return H_SUCCESS; > } > EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);
diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c index 89e96b3..f29ba2c 100644 --- a/arch/powerpc/kvm/book3s_64_vio_hv.c +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c @@ -35,71 +35,104 @@ #include <asm/ppc-opcode.h> #include <asm/kvm_host.h> #include <asm/udbg.h> +#include <asm/iommu.h> #define TCES_PER_PAGE (PAGE_SIZE / sizeof(u64)) +/* + * Finds a TCE table descriptor by LIOBN. + * + * WARNING: This will be called in real or virtual mode on HV KVM and virtual + * mode on PR KVM + */ +static struct kvmppc_spapr_tce_table *kvmppc_find_table(struct kvm_vcpu *vcpu, + unsigned long liobn) +{ + struct kvm *kvm = vcpu->kvm; + struct kvmppc_spapr_tce_table *stt; + + list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) + if (stt->liobn == liobn) + return stt; + + return NULL; +} + +/* + * Validates IO address. + * + * WARNING: This will be called in real-mode on HV KVM and virtual + * mode on PR KVM + */ +static long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt, + unsigned long ioba, unsigned long npages) +{ + unsigned long mask = (1ULL << IOMMU_PAGE_SHIFT_4K) - 1; + unsigned long idx = ioba >> IOMMU_PAGE_SHIFT_4K; + unsigned long size = stt->window_size >> IOMMU_PAGE_SHIFT_4K; + + if ((ioba & mask) || (idx + npages > size) || (idx + npages < idx)) + return H_PARAMETER; + + return H_SUCCESS; +} + /* WARNING: This will be called in real-mode on HV KVM and virtual * mode on PR KVM */ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, unsigned long ioba, unsigned long tce) { - struct kvm *kvm = vcpu->kvm; - struct kvmppc_spapr_tce_table *stt; + struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn); + long ret; + unsigned long idx; + struct page *page; + u64 *tbl; /* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */ /* liobn, ioba, tce); */ - list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) { - if (stt->liobn == liobn) { - unsigned long idx = ioba >> SPAPR_TCE_SHIFT; - struct page *page; - u64 *tbl; + if (!stt) + return H_TOO_HARD; - /* udbg_printf("H_PUT_TCE: liobn 0x%lx => stt=%p window_size=0x%x\n", */ - /* liobn, stt, stt->window_size); */ - if (ioba >= stt->window_size) - return H_PARAMETER; + ret = kvmppc_ioba_validate(stt, ioba, 1); + if (ret != H_SUCCESS) + return ret; - page = stt->pages[idx / TCES_PER_PAGE]; - tbl = (u64 *)page_address(page); + idx = ioba >> SPAPR_TCE_SHIFT; + page = stt->pages[idx / TCES_PER_PAGE]; + tbl = (u64 *)page_address(page); - /* FIXME: Need to validate the TCE itself */ - /* udbg_printf("tce @ %p\n", &tbl[idx % TCES_PER_PAGE]); */ - tbl[idx % TCES_PER_PAGE] = tce; - return H_SUCCESS; - } - } + /* FIXME: Need to validate the TCE itself */ + /* udbg_printf("tce @ %p\n", &tbl[idx % TCES_PER_PAGE]); */ + tbl[idx % TCES_PER_PAGE] = tce; - /* Didn't find the liobn, punt it to userspace */ - return H_TOO_HARD; + return H_SUCCESS; } EXPORT_SYMBOL_GPL(kvmppc_h_put_tce); long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn, unsigned long ioba) { - struct kvm *kvm = vcpu->kvm; - struct kvmppc_spapr_tce_table *stt; + struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn); + long ret; + unsigned long idx; + struct page *page; + u64 *tbl; - list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) { - if (stt->liobn == liobn) { - unsigned long idx = ioba >> SPAPR_TCE_SHIFT; - struct page *page; - u64 *tbl; + if (!stt) + return H_TOO_HARD; - if (ioba >= stt->window_size) - return H_PARAMETER; + ret = kvmppc_ioba_validate(stt, ioba, 1); + if (ret != H_SUCCESS) + return ret; - page = stt->pages[idx / TCES_PER_PAGE]; - tbl = (u64 *)page_address(page); + idx = ioba >> SPAPR_TCE_SHIFT; + page = stt->pages[idx / TCES_PER_PAGE]; + tbl = (u64 *)page_address(page); - vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; - return H_SUCCESS; - } - } + vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; - /* Didn't find the liobn, punt it to userspace */ - return H_TOO_HARD; + return H_SUCCESS; } EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);
This reworks the existing H_PUT_TCE/H_GET_TCE handlers to have following patches applied nicer. This moves the ioba boundaries check to a helper and adds a check for least bits which have to be zeros. The patch is pretty mechanical (only check for least ioba bits is added) so no change in behaviour is expected. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> --- Changelog: v3: * moved list_for_each_entry_lockless() to the next patch * added overflow check in kvmppc_ioba_validate() as H_STUFF_TCE handles more than just 512 TCEs at once v2: * compare @ret with H_SUCCESS instead of assuming H_SUCCESS is zero * made error reporting cleaner --- arch/powerpc/kvm/book3s_64_vio_hv.c | 109 +++++++++++++++++++++++------------- 1 file changed, 71 insertions(+), 38 deletions(-)