On 17/10/18 09:19, Paul Durrant wrote:
> diff --git a/xen/arch/x86/mm/p2m-pt.c b/xen/arch/x86/mm/p2m-pt.c
> index 55df18501e..b264a97bd8 100644
> --- a/xen/arch/x86/mm/p2m-pt.c
> +++ b/xen/arch/x86/mm/p2m-pt.c
> @@ -683,41 +684,13 @@ p2m_pt_set_entry(struct p2m_domain *p2m, gfn_t gfn_,
> mfn_t mfn,
> {
> ASSERT(rc == 0);
>
> - if ( iommu_use_hap_pt(p2m->domain) )
> - {
> - if ( iommu_old_flags )
> - amd_iommu_flush_pages(p2m->domain, gfn, page_order);
> - }
> - else if ( need_iommu_pt_sync(p2m->domain) )
> - {
> - dfn_t dfn = _dfn(gfn);
> -
> - if ( iommu_pte_flags )
> - for ( i = 0; i < (1UL << page_order); i++ )
> - {
> - rc = iommu_map_page(p2m->domain, dfn_add(dfn, i),
> - mfn_add(mfn, i), iommu_pte_flags);
> - if ( unlikely(rc) )
> - {
> - while ( i-- )
> - /* If statement to satisfy __must_check. */
> - if ( iommu_unmap_page(p2m->domain,
> - dfn_add(dfn, i)) )
> - continue;
> -
> - break;
> - }
> - }
> - else
> - for ( i = 0; i < (1UL << page_order); i++ )
> - {
> - int ret = iommu_unmap_page(p2m->domain,
> - dfn_add(dfn, i));
> -
> - if ( !rc )
> - rc = ret;
> - }
> - }
> + if ( need_iommu_pt_sync(p2m->domain) )
> + rc = iommu_pte_flags ?
> + iommu_map_page(d, _dfn(gfn), mfn, page_order,
> + iommu_pte_flags) :
> + iommu_unmap_page(d, _dfn(gfn), page_order);
> + else if ( iommu_use_hap_pt(d) && iommu_old_flags )
> + amd_iommu_flush_pages(p2m->domain, gfn, page_order);
This logically reverses the
iommu_use_hap_pt(d)/need_iommu_pt_sync(p2m->domain) conditions.
I'd be tempted confine this change to the else if (
need_iommu_pt_sync(p2m->domain) ) block.
Tangentially related, calling amd_iommu_flush_pages() is a laying
violation here because this is supposedly common code. In reality, it
is the NPT code, so might perhaps be better named as p2m-npt.c. George?
> }
>
> /*
> diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
> index f1df1debc7..3fa559da01 100644
> --- a/xen/arch/x86/mm/p2m.c
> +++ b/xen/arch/x86/mm/p2m.c
> @@ -718,24 +718,8 @@ p2m_remove_page(struct p2m_domain *p2m, unsigned long
> gfn_l, unsigned long mfn,
> p2m_access_t a;
>
> if ( !paging_mode_translate(p2m->domain) )
> - {
> - int rc = 0;
> -
> - if ( need_iommu_pt_sync(p2m->domain) )
> - {
> - dfn_t dfn = _dfn(mfn);
> -
> - for ( i = 0; i < (1 << page_order); i++ )
> - {
> - int ret = iommu_unmap_page(p2m->domain, dfn_add(dfn, i));
> -
> - if ( !rc )
> - rc = ret;
> - }
> - }
> -
> - return rc;
> - }
> + return need_iommu_pt_sync(p2m->domain) ?
> + iommu_unmap_page(p2m->domain, _dfn(mfn), page_order) : 0;
TBH, I think this is harder to read than the non ternary alternative.
>
> ASSERT(gfn_locked_by_me(p2m, gfn));
> P2M_DEBUG("removing gfn=%#lx mfn=%#lx\n", gfn_l, mfn);
> diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
> index 8b438ae4bc..40db9e7849 100644
> --- a/xen/drivers/passthrough/iommu.c
> +++ b/xen/drivers/passthrough/iommu.c
> @@ -305,50 +305,71 @@ void iommu_domain_destroy(struct domain *d)
> }
>
> int iommu_map_page(struct domain *d, dfn_t dfn, mfn_t mfn,
> - unsigned int flags)
> + unsigned int page_order, unsigned int flags)
> {
> const struct domain_iommu *hd = dom_iommu(d);
> - int rc;
> + unsigned long i;
>
> if ( !iommu_enabled || !hd->platform_ops )
> return 0;
>
> - rc = hd->platform_ops->map_page(d, dfn, mfn, flags);
> - if ( unlikely(rc) )
> + for ( i = 0; i < (1ul << page_order); i++ )
> {
> - if ( !d->is_shutting_down && printk_ratelimit() )
> - printk(XENLOG_ERR
> - "d%d: IOMMU mapping dfn %"PRI_dfn" to mfn %"PRI_mfn"
> failed: %d\n",
> - d->domain_id, dfn_x(dfn), mfn_x(mfn), rc);
> + int ignored, rc = hd->platform_ops->map_page(d, dfn_add(dfn, i),
> + mfn_add(mfn, i),
> + flags);
>
> - if ( !is_hardware_domain(d) )
> - domain_crash(d);
> + if ( unlikely(rc) )
> + {
> + while (i--)
Spaces, but you're also off-by-one when cleaning up i = 0. Wouldn't it
be easier to reuse iommu_unmap_page() rather than opencode it?
~Andrew
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
