[2/6] x86/mm: p2m_add_foreign() is HVM-only

Message ID	cf4569c5-a9c5-7b4b-d576-d1521c369418@suse.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <SRS0=ELVT=FT=lists.xenproject.org=xen-devel-bounces@kernel.org> DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 690452078B Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" <xen-devel-bounces@lists.xenproject.org> Subject: [PATCH 2/6] x86/mm: p2m_add_foreign() is HVM-only From: Jan Beulich <jbeulich@suse.com> To: "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com>, Wei Liu <wl@xen.org>, =?utf-8?q?Roger_Pau_Monn=C3=A9?= <roger.pau@citrix.com>, George Dunlap <george.dunlap@citrix.com> References: <be9ce75e-9119-2b5a-9e7b-437beb7ee446@suse.com> Message-ID: <cf4569c5-a9c5-7b4b-d576-d1521c369418@suse.com> Date: Tue, 15 Dec 2020 17:26:08 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 In-Reply-To: <be9ce75e-9119-2b5a-9e7b-437beb7ee446@suse.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit
Series	x86/p2m: restrict more code to build just for HVM \| expand [0/6] x86/p2m: restrict more code to build just for HVM [1/6] x86/p2m: tidy p2m_add_foreign() a little [2/6] x86/mm: p2m_add_foreign() is HVM-only [3/6] x86/p2m: set_{foreign,mmio}_p2m_entry() are HVM-only [4/6] x86/p2m: {,un}map_mmio_regions() are HVM-only [5/6] x86/mm: the gva_to_gfn() hook is HVM-only [6/6] x86/p2m: set_shared_p2m_entry() is MEM_SHARING-only

--- a/xen/arch/x86/mm.c +++ b/xen/arch/x86/mm.c @@ -118,7 +118,6 @@ #include <xen/vmap.h> #include <xen/xmalloc.h> #include <xen/efi.h> -#include <xen/grant_table.h> #include <xen/hypercall.h> #include <xen/mm.h> #include <asm/paging.h> @@ -142,10 +141,7 @@ #include <asm/pci.h> #include <asm/guest.h> #include <asm/hvm/ioreq.h> - -#include <asm/hvm/grant_table.h> #include <asm/pv/domain.h> -#include <asm/pv/grant_table.h> #include <asm/pv/mm.h> #ifdef CONFIG_PV @@ -4591,114 +4587,6 @@ static int handle_iomem_range(unsigned l return err || s > e ? err : _handle_iomem_range(s, e, p); } -int xenmem_add_to_physmap_one( - struct domain *d, - unsigned int space, - union add_to_physmap_extra extra, - unsigned long idx, - gfn_t gpfn) -{ - struct page_info *page = NULL; - unsigned long gfn = 0 /* gcc ... */, old_gpfn; - mfn_t prev_mfn; - int rc = 0; - mfn_t mfn = INVALID_MFN; - p2m_type_t p2mt; - - switch ( space ) - { - case XENMAPSPACE_shared_info: - if ( idx == 0 ) - mfn = virt_to_mfn(d->shared_info); - break; - case XENMAPSPACE_grant_table: - rc = gnttab_map_frame(d, idx, gpfn, &mfn); - if ( rc ) - return rc; - break; - case XENMAPSPACE_gmfn: - { - p2m_type_t p2mt; - - gfn = idx; - mfn = get_gfn_unshare(d, gfn, &p2mt); - /* If the page is still shared, exit early */ - if ( p2m_is_shared(p2mt) ) - { - put_gfn(d, gfn); - return -ENOMEM; - } - page = get_page_from_mfn(mfn, d); - if ( unlikely(!page) ) - mfn = INVALID_MFN; - break; - } - case XENMAPSPACE_gmfn_foreign: - return p2m_add_foreign(d, idx, gfn_x(gpfn), extra.foreign_domid); - default: - break; - } - - if ( mfn_eq(mfn, INVALID_MFN) ) - { - rc = -EINVAL; - goto put_both; - } - - /* Remove previously mapped page if it was present. */ - prev_mfn = get_gfn(d, gfn_x(gpfn), &p2mt); - if ( mfn_valid(prev_mfn) ) - { - if ( is_special_page(mfn_to_page(prev_mfn)) ) - /* Special pages are simply unhooked from this phys slot. */ - rc = guest_physmap_remove_page(d, gpfn, prev_mfn, PAGE_ORDER_4K); - else if ( !mfn_eq(mfn, prev_mfn) ) - /* Normal domain memory is freed, to avoid leaking memory. */ - rc = guest_remove_page(d, gfn_x(gpfn)); - } - /* In the XENMAPSPACE_gmfn case we still hold a ref on the old page. */ - put_gfn(d, gfn_x(gpfn)); - - if ( rc ) - goto put_both; - - /* Unmap from old location, if any. */ - old_gpfn = get_gpfn_from_mfn(mfn_x(mfn)); - ASSERT(!SHARED_M2P(old_gpfn)); - if ( space == XENMAPSPACE_gmfn && old_gpfn != gfn ) - { - rc = -EXDEV; - goto put_both; - } - if ( old_gpfn != INVALID_M2P_ENTRY ) - rc = guest_physmap_remove_page(d, _gfn(old_gpfn), mfn, PAGE_ORDER_4K); - - /* Map at new location. */ - if ( !rc ) - rc = guest_physmap_add_page(d, gpfn, mfn, PAGE_ORDER_4K); - - put_both: - /* - * In the XENMAPSPACE_gmfn case, we took a ref of the gfn at the top. - * We also may need to transfer ownership of the page reference to our - * caller. - */ - if ( space == XENMAPSPACE_gmfn ) - { - put_gfn(d, gfn); - if ( !rc && extra.ppage ) - { - *extra.ppage = page; - page = NULL; - } - } - - if ( page ) - put_page(page); - - return rc; -} - int arch_acquire_resource(struct domain *d, unsigned int type, unsigned int id, unsigned long frame, unsigned int nr_frames, xen_pfn_t mfn_list[]) --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -27,6 +27,7 @@ #include <xen/mem_access.h> #include <xen/vm_event.h> #include <xen/event.h> +#include <xen/grant_table.h> #include <xen/param.h> #include <public/vm_event.h> #include <asm/domain.h> @@ -42,6 +43,10 @@ #include "mm-locks.h" +/* Override macro from asm/page.h to make work with mfn_t */ +#undef virt_to_mfn +#define virt_to_mfn(v) _mfn(__virt_to_mfn(v)) + /* Turn on/off host superpage page table support for hap, default on. */ bool_t __initdata opt_hap_1gb = 1, __initdata opt_hap_2mb = 1; boolean_param("hap_1gb", opt_hap_1gb); @@ -2535,6 +2540,8 @@ out_p2m_audit: } #endif /* P2M_AUDIT */ +#ifdef CONFIG_HVM + /* * Add frame from foreign domain to target domain's physmap. Similar to * XENMAPSPACE_gmfn but the frame is foreign being mapped into current, @@ -2551,8 +2558,8 @@ out_p2m_audit: * * Returns: 0 ==> success */ -int p2m_add_foreign(struct domain *tdom, unsigned long fgfn, - unsigned long gpfn, domid_t foreigndom) +static int p2m_add_foreign(struct domain *tdom, unsigned long fgfn, + unsigned long gpfn, domid_t foreigndom) { p2m_type_t p2mt, p2mt_prev; mfn_t prev_mfn, mfn; @@ -2639,7 +2646,114 @@ int p2m_add_foreign(struct domain *tdom, return rc; } -#ifdef CONFIG_HVM +int xenmem_add_to_physmap_one( + struct domain *d, + unsigned int space, + union add_to_physmap_extra extra, + unsigned long idx, + gfn_t gpfn) +{ + struct page_info *page = NULL; + unsigned long gfn = 0 /* gcc ... */, old_gpfn; + mfn_t prev_mfn; + int rc = 0; + mfn_t mfn = INVALID_MFN; + p2m_type_t p2mt; + + switch ( space ) + { + case XENMAPSPACE_shared_info: + if ( idx == 0 ) + mfn = virt_to_mfn(d->shared_info); + break; + case XENMAPSPACE_grant_table: + rc = gnttab_map_frame(d, idx, gpfn, &mfn); + if ( rc ) + return rc; + break; + case XENMAPSPACE_gmfn: + { + p2m_type_t p2mt; + + gfn = idx; + mfn = get_gfn_unshare(d, gfn, &p2mt); + /* If the page is still shared, exit early */ + if ( p2m_is_shared(p2mt) ) + { + put_gfn(d, gfn); + return -ENOMEM; + } + page = get_page_from_mfn(mfn, d); + if ( unlikely(!page) ) + mfn = INVALID_MFN; + break; + } + case XENMAPSPACE_gmfn_foreign: + return p2m_add_foreign(d, idx, gfn_x(gpfn), extra.foreign_domid); + default: + break; + } + + if ( mfn_eq(mfn, INVALID_MFN) ) + { + rc = -EINVAL; + goto put_both; + } + + /* Remove previously mapped page if it was present. */ + prev_mfn = get_gfn(d, gfn_x(gpfn), &p2mt); + if ( mfn_valid(prev_mfn) ) + { + if ( is_special_page(mfn_to_page(prev_mfn)) ) + /* Special pages are simply unhooked from this phys slot. */ + rc = guest_physmap_remove_page(d, gpfn, prev_mfn, PAGE_ORDER_4K); + else if ( !mfn_eq(mfn, prev_mfn) ) + /* Normal domain memory is freed, to avoid leaking memory. */ + rc = guest_remove_page(d, gfn_x(gpfn)); + } + /* In the XENMAPSPACE_gmfn case we still hold a ref on the old page. */ + put_gfn(d, gfn_x(gpfn)); + + if ( rc ) + goto put_both; + + /* Unmap from old location, if any. */ + old_gpfn = get_gpfn_from_mfn(mfn_x(mfn)); + ASSERT(!SHARED_M2P(old_gpfn)); + if ( space == XENMAPSPACE_gmfn && old_gpfn != gfn ) + { + rc = -EXDEV; + goto put_both; + } + if ( old_gpfn != INVALID_M2P_ENTRY ) + rc = guest_physmap_remove_page(d, _gfn(old_gpfn), mfn, PAGE_ORDER_4K); + + /* Map at new location. */ + if ( !rc ) + rc = guest_physmap_add_page(d, gpfn, mfn, PAGE_ORDER_4K); + + put_both: + /* + * In the XENMAPSPACE_gmfn case, we took a ref of the gfn at the top. + * We also may need to transfer ownership of the page reference to our + * caller. + */ + if ( space == XENMAPSPACE_gmfn ) + { + put_gfn(d, gfn); + if ( !rc && extra.ppage ) + { + *extra.ppage = page; + page = NULL; + } + } + + if ( page ) + put_page(page); + + return rc; +} + /* * Set/clear the #VE suppress bit for a page. Only available on VMX. */ @@ -2792,7 +2906,8 @@ int p2m_set_altp2m_view_visibility(struc return rc; } -#endif + +#endif /* CONFIG_HVM */ /* * Local variables: --- a/xen/include/asm-x86/p2m.h +++ b/xen/include/asm-x86/p2m.h @@ -661,10 +661,6 @@ int set_identity_p2m_entry(struct domain p2m_access_t p2ma, unsigned int flag); int clear_identity_p2m_entry(struct domain *d, unsigned long gfn); -/* Add foreign mapping to the guest's p2m table. */ -int p2m_add_foreign(struct domain *tdom, unsigned long fgfn, - unsigned long gpfn, domid_t foreign_domid); - /* * Populate-on-demand */

[2/6] x86/mm: p2m_add_foreign() is HVM-only

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