Message ID | 20140221153110.8190.6271.stgit@nimbus (mailing list archive) |
---|---|
State | Not Applicable |
Headers | show |
On 21.02.2014, at 16:31, Laurent Dufour <ldufour@linux.vnet.ibm.com> wrote: > This fix introduces the H_GET_TCE hypervisor call which is basically the > reverse of H_PUT_TCE, as defined in the Power Architecture Platform > Requirements (PAPR). > > The hcall H_GET_TCE is required by the kdump kernel which is calling it to > retrieve the TCE set up by the panicing kernel. > > Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Thanks, applied to kvm-ppc-queue. Btw, why exactly are we using struct page pointers and alloc_page rather than __get_free_page() and simple page start pointers? Alex
On Fri, 2014-02-21 at 16:31 +0100, Laurent Dufour wrote: > This fix introduces the H_GET_TCE hypervisor call which is basically the > reverse of H_PUT_TCE, as defined in the Power Architecture Platform > Requirements (PAPR). > > The hcall H_GET_TCE is required by the kdump kernel which is calling it to > retrieve the TCE set up by the panicing kernel. Alexey, will that work for VFIO ? Or are those patches *still* not upstream ? > Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> > --- > arch/powerpc/include/asm/kvm_ppc.h | 2 ++ > arch/powerpc/kvm/book3s_64_vio_hv.c | 28 ++++++++++++++++++++++++++++ > arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 +- > 3 files changed, 31 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h > index fcd53f0..4096f16 100644 > --- a/arch/powerpc/include/asm/kvm_ppc.h > +++ b/arch/powerpc/include/asm/kvm_ppc.h > @@ -129,6 +129,8 @@ extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, > struct kvm_create_spapr_tce *args); > extern long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, > unsigned long ioba, unsigned long tce); > +extern long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn, > + unsigned long ioba); > extern struct kvm_rma_info *kvm_alloc_rma(void); > extern void kvm_release_rma(struct kvm_rma_info *ri); > extern struct page *kvm_alloc_hpt(unsigned long nr_pages); > diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c > index 2c25f54..89e96b3 100644 > --- a/arch/powerpc/kvm/book3s_64_vio_hv.c > +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c > @@ -75,3 +75,31 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, > return H_TOO_HARD; > } > 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; > + > + 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 (ioba >= stt->window_size) > + return H_PARAMETER; > + > + page = stt->pages[idx / TCES_PER_PAGE]; > + tbl = (u64 *)page_address(page); > + > + vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; > + return H_SUCCESS; > + } > + } > + > + /* Didn't find the liobn, punt it to userspace */ > + return H_TOO_HARD; > +} > +EXPORT_SYMBOL_GPL(kvmppc_h_get_tce); > diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S > index e66d4ec..7d4fe2a 100644 > --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S > +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S > @@ -1758,7 +1758,7 @@ hcall_real_table: > .long 0 /* 0x10 - H_CLEAR_MOD */ > .long 0 /* 0x14 - H_CLEAR_REF */ > .long .kvmppc_h_protect - hcall_real_table > - .long 0 /* 0x1c - H_GET_TCE */ > + .long .kvmppc_h_get_tce - hcall_real_table > .long .kvmppc_h_put_tce - hcall_real_table > .long 0 /* 0x24 - H_SET_SPRG0 */ > .long .kvmppc_h_set_dabr - hcall_real_table
On 02/22/2014 06:23 AM, Benjamin Herrenschmidt wrote: > On Fri, 2014-02-21 at 16:31 +0100, Laurent Dufour wrote: >> This fix introduces the H_GET_TCE hypervisor call which is basically the >> reverse of H_PUT_TCE, as defined in the Power Architecture Platform >> Requirements (PAPR). >> >> The hcall H_GET_TCE is required by the kdump kernel which is calling it to >> retrieve the TCE set up by the panicing kernel. > > Alexey, will that work for VFIO ? Yes. > Or are those patches *still* not > upstream ? Yes. > >> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> >> --- >> arch/powerpc/include/asm/kvm_ppc.h | 2 ++ >> arch/powerpc/kvm/book3s_64_vio_hv.c | 28 ++++++++++++++++++++++++++++ >> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 +- >> 3 files changed, 31 insertions(+), 1 deletion(-) >> >> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h >> index fcd53f0..4096f16 100644 >> --- a/arch/powerpc/include/asm/kvm_ppc.h >> +++ b/arch/powerpc/include/asm/kvm_ppc.h >> @@ -129,6 +129,8 @@ extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, >> struct kvm_create_spapr_tce *args); >> extern long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, >> unsigned long ioba, unsigned long tce); >> +extern long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn, >> + unsigned long ioba); >> extern struct kvm_rma_info *kvm_alloc_rma(void); >> extern void kvm_release_rma(struct kvm_rma_info *ri); >> extern struct page *kvm_alloc_hpt(unsigned long nr_pages); >> diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c >> index 2c25f54..89e96b3 100644 >> --- a/arch/powerpc/kvm/book3s_64_vio_hv.c >> +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c >> @@ -75,3 +75,31 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, >> return H_TOO_HARD; >> } >> 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; >> + >> + 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 (ioba >= stt->window_size) >> + return H_PARAMETER; >> + >> + page = stt->pages[idx / TCES_PER_PAGE]; >> + tbl = (u64 *)page_address(page); >> + >> + vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; >> + return H_SUCCESS; >> + } >> + } >> + >> + /* Didn't find the liobn, punt it to userspace */ >> + return H_TOO_HARD; >> +} >> +EXPORT_SYMBOL_GPL(kvmppc_h_get_tce); >> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S >> index e66d4ec..7d4fe2a 100644 >> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S >> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S >> @@ -1758,7 +1758,7 @@ hcall_real_table: >> .long 0 /* 0x10 - H_CLEAR_MOD */ >> .long 0 /* 0x14 - H_CLEAR_REF */ >> .long .kvmppc_h_protect - hcall_real_table >> - .long 0 /* 0x1c - H_GET_TCE */ >> + .long .kvmppc_h_get_tce - hcall_real_table >> .long .kvmppc_h_put_tce - hcall_real_table >> .long 0 /* 0x24 - H_SET_SPRG0 */ >> .long .kvmppc_h_set_dabr - hcall_real_table > > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev >
On 02/22/2014 11:28 AM, Alexey Kardashevskiy wrote: > On 02/22/2014 06:23 AM, Benjamin Herrenschmidt wrote: >> On Fri, 2014-02-21 at 16:31 +0100, Laurent Dufour wrote: >>> This fix introduces the H_GET_TCE hypervisor call which is basically the >>> reverse of H_PUT_TCE, as defined in the Power Architecture Platform >>> Requirements (PAPR). >>> >>> The hcall H_GET_TCE is required by the kdump kernel which is calling it to >>> retrieve the TCE set up by the panicing kernel. >> >> Alexey, will that work for VFIO ? > > Yes. Oh! My bad, this is _G_et. Not, this won't support VFIO but this should not break the current "slow" VFIO support in upstream. >> Or are those patches *still* not >> upstream ? > > Yes. This part is still true. I cannot get Alex Graf attention even on much simpler things for several months. > > >> >>> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> >>> --- >>> arch/powerpc/include/asm/kvm_ppc.h | 2 ++ >>> arch/powerpc/kvm/book3s_64_vio_hv.c | 28 ++++++++++++++++++++++++++++ >>> arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 +- >>> 3 files changed, 31 insertions(+), 1 deletion(-) >>> >>> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h >>> index fcd53f0..4096f16 100644 >>> --- a/arch/powerpc/include/asm/kvm_ppc.h >>> +++ b/arch/powerpc/include/asm/kvm_ppc.h >>> @@ -129,6 +129,8 @@ extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, >>> struct kvm_create_spapr_tce *args); >>> extern long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, >>> unsigned long ioba, unsigned long tce); >>> +extern long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn, >>> + unsigned long ioba); >>> extern struct kvm_rma_info *kvm_alloc_rma(void); >>> extern void kvm_release_rma(struct kvm_rma_info *ri); >>> extern struct page *kvm_alloc_hpt(unsigned long nr_pages); >>> diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c >>> index 2c25f54..89e96b3 100644 >>> --- a/arch/powerpc/kvm/book3s_64_vio_hv.c >>> +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c >>> @@ -75,3 +75,31 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, >>> return H_TOO_HARD; >>> } >>> 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; >>> + >>> + 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 (ioba >= stt->window_size) >>> + return H_PARAMETER; >>> + >>> + page = stt->pages[idx / TCES_PER_PAGE]; >>> + tbl = (u64 *)page_address(page); >>> + >>> + vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; >>> + return H_SUCCESS; >>> + } >>> + } >>> + >>> + /* Didn't find the liobn, punt it to userspace */ >>> + return H_TOO_HARD; >>> +} >>> +EXPORT_SYMBOL_GPL(kvmppc_h_get_tce); >>> diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S >>> index e66d4ec..7d4fe2a 100644 >>> --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S >>> +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S >>> @@ -1758,7 +1758,7 @@ hcall_real_table: >>> .long 0 /* 0x10 - H_CLEAR_MOD */ >>> .long 0 /* 0x14 - H_CLEAR_REF */ >>> .long .kvmppc_h_protect - hcall_real_table >>> - .long 0 /* 0x1c - H_GET_TCE */ >>> + .long .kvmppc_h_get_tce - hcall_real_table >>> .long .kvmppc_h_put_tce - hcall_real_table >>> .long 0 /* 0x24 - H_SET_SPRG0 */ >>> .long .kvmppc_h_set_dabr - hcall_real_table >> >> >> _______________________________________________ >> Linuxppc-dev mailing list >> Linuxppc-dev@lists.ozlabs.org >> https://lists.ozlabs.org/listinfo/linuxppc-dev >> > >
On 21/02/2014 16:57, Alexander Graf wrote: > > On 21.02.2014, at 16:31, Laurent Dufour <ldufour@linux.vnet.ibm.com> wrote: > >> This fix introduces the H_GET_TCE hypervisor call which is basically the >> reverse of H_PUT_TCE, as defined in the Power Architecture Platform >> Requirements (PAPR). >> >> The hcall H_GET_TCE is required by the kdump kernel which is calling it to >> retrieve the TCE set up by the panicing kernel. >> >> Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> > > Thanks, applied to kvm-ppc-queue. Btw, why exactly are we using struct page pointers and alloc_page rather than __get_free_page() and simple page start pointers? FWIW, I'm not so familiar with that part of code, it seems that this is due to the page fault handler (kvm_spapr_tce_fault) which is part of the mmap file operation handlers associated to the fd returned by kvm_vm_ioctl_create_spapr_tce. Underlying vma's operation requires the page fault handler to return a struct page value in the vm_fault structure. Cheers, Laurent.
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index fcd53f0..4096f16 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -129,6 +129,8 @@ extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, struct kvm_create_spapr_tce *args); extern long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, unsigned long ioba, unsigned long tce); +extern long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn, + unsigned long ioba); extern struct kvm_rma_info *kvm_alloc_rma(void); extern void kvm_release_rma(struct kvm_rma_info *ri); extern struct page *kvm_alloc_hpt(unsigned long nr_pages); diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c index 2c25f54..89e96b3 100644 --- a/arch/powerpc/kvm/book3s_64_vio_hv.c +++ b/arch/powerpc/kvm/book3s_64_vio_hv.c @@ -75,3 +75,31 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn, return H_TOO_HARD; } 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; + + 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 (ioba >= stt->window_size) + return H_PARAMETER; + + page = stt->pages[idx / TCES_PER_PAGE]; + tbl = (u64 *)page_address(page); + + vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE]; + return H_SUCCESS; + } + } + + /* Didn't find the liobn, punt it to userspace */ + return H_TOO_HARD; +} +EXPORT_SYMBOL_GPL(kvmppc_h_get_tce); diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index e66d4ec..7d4fe2a 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1758,7 +1758,7 @@ hcall_real_table: .long 0 /* 0x10 - H_CLEAR_MOD */ .long 0 /* 0x14 - H_CLEAR_REF */ .long .kvmppc_h_protect - hcall_real_table - .long 0 /* 0x1c - H_GET_TCE */ + .long .kvmppc_h_get_tce - hcall_real_table .long .kvmppc_h_put_tce - hcall_real_table .long 0 /* 0x24 - H_SET_SPRG0 */ .long .kvmppc_h_set_dabr - hcall_real_table
This fix introduces the H_GET_TCE hypervisor call which is basically the reverse of H_PUT_TCE, as defined in the Power Architecture Platform Requirements (PAPR). The hcall H_GET_TCE is required by the kdump kernel which is calling it to retrieve the TCE set up by the panicing kernel. Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> --- arch/powerpc/include/asm/kvm_ppc.h | 2 ++ arch/powerpc/kvm/book3s_64_vio_hv.c | 28 ++++++++++++++++++++++++++++ arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 +- 3 files changed, 31 insertions(+), 1 deletion(-)