KVM: PPC: Create a virtual-mode only TCE table handlers

Upcoming in-kernel VFIO acceleration needs different handling in real and virtual modes which makes it hard to support both modes in the same handler.

This creates a copy of kvmppc_rm_h_stuff_tce and kvmppc_rm_h_put_tce in addition to the existing kvmppc_rm_h_put_tce_indirect.

This also fixes linker breakage when only PR KVM was selected (leaving HV KVM off): the kvmppc_h_put_tce/kvmppc_h_stuff_tce functions would not compile at all and the linked would fail.

Signed-off-by Alexey Kardashevskiy <[email protected]>

---
  arch/powerpc/kvm/book3s_64_vio.c        | 52 +++++++++++++++++++++++++++++++++
  arch/powerpc/kvm/book3s_64_vio_hv.c     |  8 ++---
  arch/powerpc/kvm/book3s_hv_rmhandlers.S |  4 +--
  3 files changed, 57 insertions(+), 7 deletions(-)

arch/powerpc/kvm/book3s_64_vio.c +52 -0

index 2c2d103..75469f6 100644
@@ -209,6 +209,32 @@ fail:
  	return ret;
  }
 
+long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
+		      unsigned long ioba, unsigned long tce)
+{
+	struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn);
+	long ret;
+
+	/* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
+	/* 	    liobn, ioba, tce); */
+
+	if (!stt)
+		return H_TOO_HARD;
+
+	ret = kvmppc_ioba_validate(stt, ioba, 1);
+	if (ret != H_SUCCESS)
+		return ret;
+
+	ret = kvmppc_tce_validate(stt, tce);
+	if (ret != H_SUCCESS)
+		return ret;
+
+	kvmppc_tce_put(stt, ioba >> stt->page_shift, tce);
+
+	return H_SUCCESS;
+}
+EXPORT_SYMBOL_GPL(kvmppc_h_put_tce);
+
  long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu,
  		unsigned long liobn, unsigned long ioba,
  		unsigned long tce_list, unsigned long npages)

@@ -264,3 +290,29 @@ unlock_exit:
  	return ret;
  }
  EXPORT_SYMBOL_GPL(kvmppc_h_put_tce_indirect);
+
+long kvmppc_h_stuff_tce(struct kvm_vcpu *vcpu,
+		unsigned long liobn, unsigned long ioba,
+		unsigned long tce_value, unsigned long npages)
+{
+	struct kvmppc_spapr_tce_table *stt;
+	long i, ret;
+
+	stt = kvmppc_find_table(vcpu, liobn);
+	if (!stt)
+		return H_TOO_HARD;
+
+	ret = kvmppc_ioba_validate(stt, ioba, npages);
+	if (ret != H_SUCCESS)
+		return ret;
+
+	/* Check permission bits only to allow userspace poison TCE for debug */
+	if (tce_value & (TCE_PCI_WRITE | TCE_PCI_READ))
+		return H_PARAMETER;
+
+	for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift))
+		kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value);
+
+	return H_SUCCESS;
+}
+EXPORT_SYMBOL_GPL(kvmppc_h_stuff_tce);

arch/powerpc/kvm/book3s_64_vio_hv.c +3 -5

index 44be73e..18f0227 100644
@@ -180,8 +180,8 @@ long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa,
  EXPORT_SYMBOL_GPL(kvmppc_gpa_to_ua);
 
  #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
-		      unsigned long ioba, unsigned long tce)
+long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
+		unsigned long ioba, unsigned long tce)
  {
  	struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn);
  	long ret;

@@ -204,7 +204,6 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
 
  	return H_SUCCESS;
  }
-EXPORT_SYMBOL_GPL(kvmppc_h_put_tce);
 
  static long kvmppc_rm_ua_to_hpa(struct kvm_vcpu *vcpu,
  		unsigned long ua, unsigned long *phpa)

@@ -296,7 +295,7 @@ unlock_exit:
  	return ret;
  }
 
-long kvmppc_h_stuff_tce(struct kvm_vcpu *vcpu,
+long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
  		unsigned long liobn, unsigned long ioba,
  		unsigned long tce_value, unsigned long npages)
  {

@@ -320,7 +319,6 @@ long kvmppc_h_stuff_tce(struct kvm_vcpu *vcpu,
 
  	return H_SUCCESS;
  }
-EXPORT_SYMBOL_GPL(kvmppc_h_stuff_tce);
 
  long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
  		      unsigned long ioba)

arch/powerpc/kvm/book3s_hv_rmhandlers.S +2 -2

index 85b32f1..81b0b51 100644
@@ -1942,7 +1942,7 @@ hcall_real_table:
  	.long	DOTSYM(kvmppc_h_clear_ref) - hcall_real_table
  	.long	DOTSYM(kvmppc_h_protect) - hcall_real_table
  	.long	DOTSYM(kvmppc_h_get_tce) - hcall_real_table
-	.long	DOTSYM(kvmppc_h_put_tce) - hcall_real_table
+	.long	DOTSYM(kvmppc_rm_h_put_tce) - hcall_real_table
  	.long	0		/* 0x24 - H_SET_SPRG0 */
  	.long	DOTSYM(kvmppc_h_set_dabr) - hcall_real_table
  	.long	0		/* 0x2c */

@@ -2020,7 +2020,7 @@ hcall_real_table:
  	.long	0		/* 0x12c */
  	.long	0		/* 0x130 */
  	.long	DOTSYM(kvmppc_h_set_xdabr) - hcall_real_table
-	.long	DOTSYM(kvmppc_h_stuff_tce) - hcall_real_table
+	.long	DOTSYM(kvmppc_rm_h_stuff_tce) - hcall_real_table
  	.long	DOTSYM(kvmppc_rm_h_put_tce_indirect) - hcall_real_table
  	.long	0		/* 0x140 */
  	.long	0		/* 0x144 */

Upcoming in-kernel VFIO acceleration needs different handling in real and virtual modes which makes it hard to support both modes in the same handler.

This creates a copy of kvmppc_rm_h_stuff_tce and kvmppc_rm_h_put_tce in addition to the existing kvmppc_rm_h_put_tce_indirect.

This also fixes linker breakage when only PR KVM was selected (leaving HV KVM off): the kvmppc_h_put_tce/kvmppc_h_stuff_tce functions would not compile at all and the linked would fail.

Signed-off-by Alexey Kardashevskiy <[email protected]>

Quoted 11 lines · Alexey Kardashevskiy

Upcoming in-kernel VFIO acceleration needs different handling in real and virtual modes which makes it hard to support both modes in the same handler.

This creates a copy of kvmppc_rm_h_stuff_tce and kvmppc_rm_h_put_tce in addition to the existing kvmppc_rm_h_put_tce_indirect.

This also fixes linker breakage when only PR KVM was selected (leaving HV KVM off): the kvmppc_h_put_tce/kvmppc_h_stuff_tce functions would not compile at all and the linked would fail.

Quoted 1 line

Signed-off-by Alexey Kardashevskiy <[email protected]>

Acked-by Paul Mackerras <[email protected]>

Paolo, will you take this directly, or do you want me to generate a pull request?