From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754819Ab2JVNq5 (ORCPT ); Mon, 22 Oct 2012 09:46:57 -0400 Received: from smtp.ctxuk.citrix.com ([62.200.22.115]:20062 "EHLO SMTP.EU.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754432Ab2JVNqd (ORCPT ); Mon, 22 Oct 2012 09:46:33 -0400 X-IronPort-AV: E=Sophos;i="4.80,629,1344211200"; d="scan'208";a="15310669" Date: Mon, 22 Oct 2012 14:46:04 +0100 From: Stefano Stabellini X-X-Sender: sstabellini@kaball.uk.xensource.com To: Konrad Rzeszutek Wilk CC: "linux-kernel@vger.kernel.org" , "xen-devel@lists.xensource.com" , "mukesh.rathor@oracle.com" , Ian Campbell , Stefano Stabellini Subject: Re: [PATCH 3/6] xen/pvh: Implements mmu changes for PVH. In-Reply-To: <1350695882-12820-4-git-send-email-konrad.wilk@oracle.com> Message-ID: References: <1350695882-12820-1-git-send-email-konrad.wilk@oracle.com> <1350695882-12820-4-git-send-email-konrad.wilk@oracle.com> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 20 Oct 2012, Konrad Rzeszutek Wilk wrote: > From: Mukesh Rathor > > First the set/clear mmio pte function makes a hypercall to update the > P2M in Xen with 1:1 mapping. Since PVH uses mostly native mmu ops, we > leave the generic (native_*) for the rest. > > Two local functions are introduced to add to xen physmap for xen remap > interface. Xen unmap interface is introduced so the privcmd pte entries > can be cleared in Xen p2m table. > > Signed-off-by: Mukesh Rathor > Signed-off-by: Konrad Rzeszutek Wilk this patch looks all right, but I would like to read Ian's feedback too > arch/x86/xen/mmu.c | 162 +++++++++++++++++++++++++++++++++++++++++++++++-- > arch/x86/xen/mmu.h | 2 + > drivers/xen/privcmd.c | 5 +- > include/xen/xen-ops.h | 5 +- > 4 files changed, 165 insertions(+), 9 deletions(-) > > diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c > index 6226c99..5747a41 100644 > --- a/arch/x86/xen/mmu.c > +++ b/arch/x86/xen/mmu.c > @@ -74,6 +74,7 @@ > #include > #include > #include > +#include > > #include "multicalls.h" > #include "mmu.h" > @@ -332,6 +333,20 @@ static void xen_set_pte(pte_t *ptep, pte_t pteval) > __xen_set_pte(ptep, pteval); > } > > +void xen_set_clr_mmio_pvh_pte(unsigned long pfn, unsigned long mfn, > + int nr_mfns, int add_mapping) > +{ > + struct physdev_map_iomem iomem; > + > + iomem.first_gfn = pfn; > + iomem.first_mfn = mfn; > + iomem.nr_mfns = nr_mfns; > + iomem.add_mapping = add_mapping; > + > + if (HYPERVISOR_physdev_op(PHYSDEVOP_map_iomem, &iomem)) > + BUG(); > +} > + > static void xen_set_pte_at(struct mm_struct *mm, unsigned long addr, > pte_t *ptep, pte_t pteval) > { > @@ -1221,6 +1236,8 @@ static void __init xen_pagetable_init(void) > #endif > paging_init(); > xen_setup_shared_info(); > + if (xen_feature(XENFEAT_auto_translated_physmap)) > + return; > #ifdef CONFIG_X86_64 > if (!xen_feature(XENFEAT_auto_translated_physmap)) { > unsigned long new_mfn_list; > @@ -1528,6 +1545,10 @@ static void __init xen_set_pte_init(pte_t *ptep, pte_t pte) > static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn) > { > struct mmuext_op op; > + > + if (xen_feature(XENFEAT_writable_page_tables)) > + return; > + > op.cmd = cmd; > op.arg1.mfn = pfn_to_mfn(pfn); > if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF)) > @@ -1725,6 +1746,10 @@ static void set_page_prot(void *addr, pgprot_t prot) > unsigned long pfn = __pa(addr) >> PAGE_SHIFT; > pte_t pte = pfn_pte(pfn, prot); > > + /* recall for PVH, page tables are native. */ > + if (xen_feature(XENFEAT_auto_translated_physmap)) > + return; > + > if (HYPERVISOR_update_va_mapping((unsigned long)addr, pte, 0)) > BUG(); > } > @@ -1802,6 +1827,9 @@ static void convert_pfn_mfn(void *v) > pte_t *pte = v; > int i; > > + if (xen_feature(XENFEAT_auto_translated_physmap)) > + return; > + > /* All levels are converted the same way, so just treat them > as ptes. */ > for (i = 0; i < PTRS_PER_PTE; i++) > @@ -1821,6 +1849,7 @@ static void __init check_pt_base(unsigned long *pt_base, unsigned long *pt_end, > (*pt_end)--; > } > } > + > /* > * Set up the initial kernel pagetable. > * > @@ -1831,6 +1860,7 @@ static void __init check_pt_base(unsigned long *pt_base, unsigned long *pt_end, > * but that's enough to get __va working. We need to fill in the rest > * of the physical mapping once some sort of allocator has been set > * up. > + * NOTE: for PVH, the page tables are native. > */ > void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) > { > @@ -1908,10 +1938,13 @@ void __init xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn) > * structure to attach it to, so make sure we just set kernel > * pgd. > */ > - xen_mc_batch(); > - __xen_write_cr3(true, __pa(init_level4_pgt)); > - xen_mc_issue(PARAVIRT_LAZY_CPU); > - > + if (xen_feature(XENFEAT_writable_page_tables)) { > + native_write_cr3(__pa(init_level4_pgt)); > + } else { > + xen_mc_batch(); > + __xen_write_cr3(true, __pa(init_level4_pgt)); > + xen_mc_issue(PARAVIRT_LAZY_CPU); > + } > /* We can't that easily rip out L3 and L2, as the Xen pagetables are > * set out this way: [L4], [L1], [L2], [L3], [L1], [L1] ... for > * the initial domain. For guests using the toolstack, they are in: > @@ -2178,8 +2211,13 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = { > > void __init xen_init_mmu_ops(void) > { > - x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve; > x86_init.paging.pagetable_init = xen_pagetable_init; > + > + if (xen_feature(XENFEAT_auto_translated_physmap)) { > + pv_mmu_ops.flush_tlb_others = xen_flush_tlb_others; > + return; > + } > + x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve; > pv_mmu_ops = xen_mmu_ops; > > memset(dummy_mapping, 0xff, PAGE_SIZE); > @@ -2455,6 +2493,89 @@ void __init xen_hvm_init_mmu_ops(void) > } > #endif > > +/* Map foreign gmfn, fgmfn, to local pfn, lpfn. This for the user space > + * creating new guest on PVH dom0 and needs to map domU pages. > + */ > +static int pvh_add_to_xen_p2m(unsigned long lpfn, unsigned long fgmfn, > + unsigned int domid) > +{ > + int rc; > + struct xen_add_to_physmap xatp = { .foreign_domid = domid }; > + > + xatp.gpfn = lpfn; > + xatp.idx = fgmfn; > + xatp.domid = DOMID_SELF; > + xatp.space = XENMAPSPACE_gmfn_foreign; > + rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp); > + if (rc) > + pr_warn("d0: Failed to map pfn (0x%lx) to mfn (0x%lx) rc:%d\n", > + lpfn, fgmfn, rc); > + return rc; > +} > + > +static int pvh_rem_xen_p2m(unsigned long spfn, int count) > +{ > + struct xen_remove_from_physmap xrp; > + int i, rc; > + > + for (i = 0; i < count; i++) { > + xrp.domid = DOMID_SELF; > + xrp.gpfn = spfn+i; > + rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp); > + if (rc) { > + pr_warn("Failed to unmap pfn:%lx rc:%d done:%d\n", > + spfn+i, rc, i); > + return 1; > + } > + } > + return 0; > +} > + > +struct pvh_remap_data { > + unsigned long fgmfn; /* foreign domain's gmfn */ > + pgprot_t prot; > + domid_t domid; > + int index; > + struct page **pages; > +}; > + > +static int pvh_map_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr, > + void *data) > +{ > + int rc; > + struct pvh_remap_data *remap = data; > + unsigned long pfn = page_to_pfn(remap->pages[remap->index++]); > + pte_t pteval = pte_mkspecial(pfn_pte(pfn, remap->prot)); > + > + rc = pvh_add_to_xen_p2m(pfn, remap->fgmfn, remap->domid); > + if (rc) > + return rc; > + native_set_pte(ptep, pteval); > + > + return 0; > +} > + > +static int pvh_remap_gmfn_range(struct vm_area_struct *vma, > + unsigned long addr, unsigned long mfn, int nr, > + pgprot_t prot, unsigned domid, > + struct page **pages) > +{ > + int err; > + struct pvh_remap_data pvhdata; > + > + BUG_ON(!pages); > + > + pvhdata.fgmfn = mfn; > + pvhdata.prot = prot; > + pvhdata.domid = domid; > + pvhdata.index = 0; > + pvhdata.pages = pages; > + err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT, > + pvh_map_pte_fn, &pvhdata); > + flush_tlb_all(); > + return err; > +} > + > #define REMAP_BATCH_SIZE 16 > > struct remap_data { > @@ -2479,7 +2600,9 @@ static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token, > int xen_remap_domain_mfn_range(struct vm_area_struct *vma, > unsigned long addr, > unsigned long mfn, int nr, > - pgprot_t prot, unsigned domid) > + pgprot_t prot, unsigned domid, > + struct page **pages) > + > { > struct remap_data rmd; > struct mmu_update mmu_update[REMAP_BATCH_SIZE]; > @@ -2494,6 +2617,10 @@ int xen_remap_domain_mfn_range(struct vm_area_struct *vma, > > BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); > > + if (xen_feature(XENFEAT_auto_translated_physmap)) { > + /* We need to update the local page tables and the xen HAP */ > + return pvh_remap_gmfn_range(vma, addr, mfn, nr, prot, domid, pages); > + } > rmd.mfn = mfn; > rmd.prot = prot; > > @@ -2523,3 +2650,26 @@ out: > return err; > } > EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range); > + > +/* Returns: 0 success */ > +int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, > + int numpgs, struct page **pages) > +{ > + if (!pages || !xen_feature(XENFEAT_auto_translated_physmap)) > + return 0; > + > + while (numpgs--) { > + > + /* the mmu has already cleaned up the process mmu resources at > + * this point (lookup_address will return NULL). */ > + unsigned long pfn = page_to_pfn(pages[numpgs]); > + > + pvh_rem_xen_p2m(pfn, 1); > + } > + /* We don't need to flush tlbs because as part of pvh_rem_xen_p2m(), > + * the hypervisor will do tlb flushes after removing the p2m entries > + * from the EPT/NPT */ > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range); > diff --git a/arch/x86/xen/mmu.h b/arch/x86/xen/mmu.h > index 73809bb..6d0bb56 100644 > --- a/arch/x86/xen/mmu.h > +++ b/arch/x86/xen/mmu.h > @@ -23,4 +23,6 @@ unsigned long xen_read_cr2_direct(void); > > extern void xen_init_mmu_ops(void); > extern void xen_hvm_init_mmu_ops(void); > +extern void xen_set_clr_mmio_pvh_pte(unsigned long pfn, unsigned long mfn, > + int nr_mfns, int add_mapping); > #endif /* _XEN_MMU_H */ > diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c > index 8adb9cc..b612267 100644 > --- a/drivers/xen/privcmd.c > +++ b/drivers/xen/privcmd.c > @@ -178,7 +178,7 @@ static int mmap_mfn_range(void *data, void *state) > msg->va & PAGE_MASK, > msg->mfn, msg->npages, > vma->vm_page_prot, > - st->domain); > + st->domain, NULL); > if (rc < 0) > return rc; > > @@ -267,7 +267,8 @@ static int mmap_batch_fn(void *data, void *state) > int ret; > > ret = xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1, > - st->vma->vm_page_prot, st->domain); > + st->vma->vm_page_prot, st->domain, > + NULL); > > /* Store error code for second pass. */ > *(st->err++) = ret; > diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h > index 6a198e4..990b43e 100644 > --- a/include/xen/xen-ops.h > +++ b/include/xen/xen-ops.h > @@ -27,6 +27,9 @@ struct vm_area_struct; > int xen_remap_domain_mfn_range(struct vm_area_struct *vma, > unsigned long addr, > unsigned long mfn, int nr, > - pgprot_t prot, unsigned domid); > + pgprot_t prot, unsigned domid, > + struct page **pages); > +int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, > + int numpgs, struct page **pages); > > #endif /* INCLUDE_XEN_OPS_H */ > -- > 1.7.7.6 >