Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit fcbb2ce6 authored by Alexey Kardashevskiy's avatar Alexey Kardashevskiy Committed by Paul Mackerras
Browse files

KVM: PPC: Rework H_PUT_TCE/H_GET_TCE handlers 



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: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent e9ab1a1c

arch/powerpc/kvm/book3s_64_vio_hv.c

+75 −42
Original line number Diff line number Diff line
@@ -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;



	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;

		}

	}



	/* 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;



	list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) {

		if (stt->liobn == liobn) {

			unsigned long idx = ioba >> SPAPR_TCE_SHIFT;

	struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn);

	long ret;

	unsigned long idx;

	struct page *page;

	u64 *tbl;



			if (ioba >= stt->window_size)

				return H_PARAMETER;

	if (!stt)

		return H_TOO_HARD;



	ret = kvmppc_ioba_validate(stt, ioba, 1);

	if (ret != H_SUCCESS)

		return ret;



	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;

		}

	}



	/* Didn't find the liobn, punt it to userspace */

	return H_TOO_HARD;

	return H_SUCCESS;

}

EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);