| Message ID | 20191213084537.27306-4-aik@ozlabs.ru (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | Enable IOMMU support for pseries Secure VMs | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (42159d2de18ffa66c2714d988a8c162db8b03956) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | warning | total: 0 errors, 0 warnings, 3 checks, 18 lines checked |
Alexey Kardashevskiy <aik@ozlabs.ru> writes: > H_PUT_TCE_INDIRECT uses a 4K page with TCEs to allow handling up to 512 > TCEs per hypercall. While it is a decent optimization, we rather share > less of secure VM memory so let's avoid sharing. > > This only allows H_PUT_TCE_INDIRECT for normal (not secure) VMs. > > This keeps using H_STUFF_TCE as it does not require sharing. > > Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> > --- > > Possible alternatives are: > > 1. define FW_FEATURE_STUFFTCE (to allow H_STUFF_TCE) in addition to > FW_FEATURE_MULTITCE (make it only enable H_PUT_TCE_INDIRECT) and enable > only FW_FEATURE_STUFFTCE for SVM; pro = no SVM mention in iommu.c, > con = a FW feature bit with very limited use Yes let's do that please. Actually let's rename FW_FEATURE_MULTITCE to FW_FEATURE_PUT_TCE_IND (?) to make it clear that's what it controls now. You should just be able to add two entries to hypertas_fw_features_table that both look for "hcall-multi-tce". And then the SVM code disables the PUT_TCE_IND feature at some point. cheers > > 2. disable FW_FEATURE_MULTITCE and loose H_STUFF_TCE which adds a delay > in booting process > --- > arch/powerpc/platforms/pseries/iommu.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c > index f6e9b87c82fc..2334a67c7614 100644 > --- a/arch/powerpc/platforms/pseries/iommu.c > +++ b/arch/powerpc/platforms/pseries/iommu.c > @@ -192,7 +192,8 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum, > int ret = 0; > unsigned long flags; > > - if ((npages == 1) || !firmware_has_feature(FW_FEATURE_MULTITCE)) { > + if ((npages == 1) || !firmware_has_feature(FW_FEATURE_MULTITCE) || > + is_secure_guest()) { > return tce_build_pSeriesLP(tbl->it_index, tcenum, > tbl->it_page_shift, npages, uaddr, > direction, attrs); > @@ -402,7 +403,8 @@ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn, > u64 rc = 0; > long l, limit; > > - if (!firmware_has_feature(FW_FEATURE_MULTITCE)) { > + if (!firmware_has_feature(FW_FEATURE_MULTITCE) || > + is_secure_guest()) { > unsigned long tceshift = be32_to_cpu(maprange->tce_shift); > unsigned long dmastart = (start_pfn << PAGE_SHIFT) + > be64_to_cpu(maprange->dma_base); > -- > 2.17.1
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index f6e9b87c82fc..2334a67c7614 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -192,7 +192,8 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum, int ret = 0; unsigned long flags; - if ((npages == 1) || !firmware_has_feature(FW_FEATURE_MULTITCE)) { + if ((npages == 1) || !firmware_has_feature(FW_FEATURE_MULTITCE) || + is_secure_guest()) { return tce_build_pSeriesLP(tbl->it_index, tcenum, tbl->it_page_shift, npages, uaddr, direction, attrs); @@ -402,7 +403,8 @@ static int tce_setrange_multi_pSeriesLP(unsigned long start_pfn, u64 rc = 0; long l, limit; - if (!firmware_has_feature(FW_FEATURE_MULTITCE)) { + if (!firmware_has_feature(FW_FEATURE_MULTITCE) || + is_secure_guest()) { unsigned long tceshift = be32_to_cpu(maprange->tce_shift); unsigned long dmastart = (start_pfn << PAGE_SHIFT) + be64_to_cpu(maprange->dma_base);
H_PUT_TCE_INDIRECT uses a 4K page with TCEs to allow handling up to 512 TCEs per hypercall. While it is a decent optimization, we rather share less of secure VM memory so let's avoid sharing. This only allows H_PUT_TCE_INDIRECT for normal (not secure) VMs. This keeps using H_STUFF_TCE as it does not require sharing. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> --- Possible alternatives are: 1. define FW_FEATURE_STUFFTCE (to allow H_STUFF_TCE) in addition to FW_FEATURE_MULTITCE (make it only enable H_PUT_TCE_INDIRECT) and enable only FW_FEATURE_STUFFTCE for SVM; pro = no SVM mention in iommu.c, con = a FW feature bit with very limited use 2. disable FW_FEATURE_MULTITCE and loose H_STUFF_TCE which adds a delay in booting process --- arch/powerpc/platforms/pseries/iommu.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)