From: kfraser@ubuntu.eng.hq.xensource.com Date: Fri, 8 Sep 2006 23:45:39 +0000 (-0700) Subject: [XEN] Remove backpointer info from page type info. No longer used. X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~15663^2~4 X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=ff27f515689c50e591dd4fd6a5b47f82cf33d489;p=xen.git [XEN] Remove backpointer info from page type info. No longer used. Replace with a flag for PAE final L2, needed for detecting PAE L2's which contain Xen mappings. Signed-off-by: Keir Fraser --- diff --git a/xen/arch/ia64/xen/mm.c b/xen/arch/ia64/xen/mm.c index 326e66c8a3..356f383534 100644 --- a/xen/arch/ia64/xen/mm.c +++ b/xen/arch/ia64/xen/mm.c @@ -1624,13 +1624,6 @@ void put_page_type(struct page_info *page) nx &= ~PGT_validated; } } - else if ( unlikely(((nx & (PGT_pinned | PGT_count_mask)) == - (PGT_pinned | 1)) && - ((nx & PGT_type_mask) != PGT_writable_page)) ) - { - /* Page is now only pinned. Make the back pointer mutable again. */ - nx |= PGT_va_mutable; - } } while ( unlikely((y = cmpxchg_rel(&page->u.inuse.type_info, x, nx)) != x) ); } @@ -1640,6 +1633,8 @@ int get_page_type(struct page_info *page, u32 type) { u32 nx, x, y = page->u.inuse.type_info; + ASSERT(!(type & ~PGT_type_mask)); + again: do { x = y; @@ -1651,29 +1646,25 @@ int get_page_type(struct page_info *page, u32 type) } else if ( unlikely((x & PGT_count_mask) == 0) ) { - if ( (x & (PGT_type_mask|PGT_va_mask)) != type ) + if ( (x & PGT_type_mask) != type ) { - if ( (x & PGT_type_mask) != (type & PGT_type_mask) ) + /* + * On type change we check to flush stale TLB entries. This + * may be unnecessary (e.g., page was GDT/LDT) but those + * circumstances should be very rare. + */ + cpumask_t mask = + page_get_owner(page)->domain_dirty_cpumask; + tlbflush_filter(mask, page->tlbflush_timestamp); + + if ( unlikely(!cpus_empty(mask)) ) { - /* - * On type change we check to flush stale TLB - * entries. This may be unnecessary (e.g., page - * was GDT/LDT) but those circumstances should be - * very rare. - */ - cpumask_t mask = - page_get_owner(page)->domain_dirty_cpumask; - tlbflush_filter(mask, page->tlbflush_timestamp); - - if ( unlikely(!cpus_empty(mask)) ) - { - perfc_incrc(need_flush_tlb_flush); - flush_tlb_mask(mask); - } + perfc_incrc(need_flush_tlb_flush); + flush_tlb_mask(mask); } /* We lose existing type, back pointer, and validity. */ - nx &= ~(PGT_type_mask | PGT_va_mask | PGT_validated); + nx &= ~(PGT_type_mask | PGT_validated); nx |= type; /* No special validation needed for writable pages. */ @@ -1682,46 +1673,22 @@ int get_page_type(struct page_info *page, u32 type) nx |= PGT_validated; } } - else + else if ( unlikely((x & PGT_type_mask) != type) ) { - if ( unlikely((x & (PGT_type_mask|PGT_va_mask)) != type) ) - { - if ( unlikely((x & PGT_type_mask) != (type & PGT_type_mask) ) ) - { - if ( ((x & PGT_type_mask) != PGT_l2_page_table) || - ((type & PGT_type_mask) != PGT_l1_page_table) ) - MEM_LOG("Bad type (saw %08x != exp %08x) " - "for mfn %016lx (pfn %016lx)", - x, type, page_to_mfn(page), - get_gpfn_from_mfn(page_to_mfn(page))); - return 0; - } - else if ( (x & PGT_va_mask) == PGT_va_mutable ) - { - /* The va backpointer is mutable, hence we update it. */ - nx &= ~PGT_va_mask; - nx |= type; /* we know the actual type is correct */ - } - else if ( ((type & PGT_va_mask) != PGT_va_mutable) && - ((type & PGT_va_mask) != (x & PGT_va_mask)) ) - { -#ifdef CONFIG_X86_PAE - /* We use backptr as extra typing. Cannot be unknown. */ - if ( (type & PGT_type_mask) == PGT_l2_page_table ) - return 0; -#endif - /* This table is possibly mapped at multiple locations. */ - nx &= ~PGT_va_mask; - nx |= PGT_va_unknown; - } - } - if ( unlikely(!(x & PGT_validated)) ) - { - /* Someone else is updating validation of this page. Wait... */ - while ( (y = page->u.inuse.type_info) == x ) - cpu_relax(); - goto again; - } + if ( ((x & PGT_type_mask) != PGT_l2_page_table) || + (type != PGT_l1_page_table) ) + MEM_LOG("Bad type (saw %08x != exp %08x) " + "for mfn %016lx (pfn %016lx)", + x, type, page_to_mfn(page), + get_gpfn_from_mfn(page_to_mfn(page))); + return 0; + } + else if ( unlikely(!(x & PGT_validated)) ) + { + /* Someone else is updating validation of this page. Wait... */ + while ( (y = page->u.inuse.type_info) == x ) + cpu_relax(); + goto again; } } while ( unlikely((y = cmpxchg_acq(&page->u.inuse.type_info, x, nx)) != x) ); diff --git a/xen/arch/powerpc/mm.c b/xen/arch/powerpc/mm.c index 1ca8f9fda4..d6ed40bce8 100644 --- a/xen/arch/powerpc/mm.c +++ b/xen/arch/powerpc/mm.c @@ -87,12 +87,6 @@ void put_page_type(struct page_info *page) /* Record TLB information for flush later. */ page->tlbflush_timestamp = tlbflush_current_time(); } - else if ( unlikely((nx & (PGT_pinned|PGT_type_mask|PGT_count_mask)) == - (PGT_pinned | 1)) ) - { - /* Page is now only pinned. Make the back pointer mutable again. */ - nx |= PGT_va_mutable; - } } while ( unlikely((y = cmpxchg(&page->u.inuse.type_info, x, nx)) != x) ); } @@ -102,6 +96,8 @@ int get_page_type(struct page_info *page, unsigned long type) { unsigned long nx, x, y = page->u.inuse.type_info; + ASSERT(!(type & ~PGT_type_mask)); + again: do { x = y; @@ -113,29 +109,25 @@ int get_page_type(struct page_info *page, unsigned long type) } else if ( unlikely((x & PGT_count_mask) == 0) ) { - if ( (x & (PGT_type_mask|PGT_va_mask)) != type ) + if ( (x & PGT_type_mask) != type ) { - if ( (x & PGT_type_mask) != (type & PGT_type_mask) ) + /* + * On type change we check to flush stale TLB entries. This + * may be unnecessary (e.g., page was GDT/LDT) but those + * circumstances should be very rare. + */ + cpumask_t mask = + page_get_owner(page)->domain_dirty_cpumask; + tlbflush_filter(mask, page->tlbflush_timestamp); + + if ( unlikely(!cpus_empty(mask)) ) { - /* - * On type change we check to flush stale TLB - * entries. This may be unnecessary (e.g., page - * was GDT/LDT) but those circumstances should be - * very rare. - */ - cpumask_t mask = - page_get_owner(page)->domain_dirty_cpumask; - tlbflush_filter(mask, page->tlbflush_timestamp); - - if ( unlikely(!cpus_empty(mask)) ) - { - perfc_incrc(need_flush_tlb_flush); - flush_tlb_mask(mask); - } + perfc_incrc(need_flush_tlb_flush); + flush_tlb_mask(mask); } /* We lose existing type, back pointer, and validity. */ - nx &= ~(PGT_type_mask | PGT_va_mask | PGT_validated); + nx &= ~(PGT_type_mask | PGT_validated); nx |= type; /* No special validation needed for writable pages. */ @@ -144,36 +136,16 @@ int get_page_type(struct page_info *page, unsigned long type) nx |= PGT_validated; } } - else + else if ( unlikely((x & PGT_type_mask) != type) ) { - if ( unlikely((x & (PGT_type_mask|PGT_va_mask)) != type) ) - { - if ( unlikely((x & PGT_type_mask) != (type & PGT_type_mask) ) ) - { - return 0; - } - else if ( (x & PGT_va_mask) == PGT_va_mutable ) - { - /* The va backpointer is mutable, hence we update it. */ - nx &= ~PGT_va_mask; - nx |= type; /* we know the actual type is correct */ - } - else if ( (type & PGT_va_mask) != PGT_va_mutable ) - { - ASSERT((type & PGT_va_mask) != (x & PGT_va_mask)); - - /* This table is possibly mapped at multiple locations. */ - nx &= ~PGT_va_mask; - nx |= PGT_va_unknown; - } - } - if ( unlikely(!(x & PGT_validated)) ) - { - /* Someone else is updating validation of this page. Wait... */ - while ( (y = page->u.inuse.type_info) == x ) - cpu_relax(); - goto again; - } + return 0; + } + if ( unlikely(!(x & PGT_validated)) ) + { + /* Someone else is updating validation of this page. Wait... */ + while ( (y = page->u.inuse.type_info) == x ) + cpu_relax(); + goto again; } } while ( unlikely((y = cmpxchg(&page->u.inuse.type_info, x, nx)) != x) ); diff --git a/xen/arch/x86/domain_build.c b/xen/arch/x86/domain_build.c index dd44e827f4..8f55ef2f40 100644 --- a/xen/arch/x86/domain_build.c +++ b/xen/arch/x86/domain_build.c @@ -510,15 +510,13 @@ int construct_dom0(struct domain *d, case 1 ... 4: page->u.inuse.type_info &= ~PGT_type_mask; page->u.inuse.type_info |= PGT_l2_page_table; - page->u.inuse.type_info |= - (count-1) << PGT_va_shift; + if ( count == 4 ) + page->u.inuse.type_info |= PGT_pae_xen_l2; get_page(page, d); /* an extra ref because of readable mapping */ break; default: page->u.inuse.type_info &= ~PGT_type_mask; page->u.inuse.type_info |= PGT_l1_page_table; - page->u.inuse.type_info |= - ((dsi.v_start>>L2_PAGETABLE_SHIFT)+(count-5))<u.inuse.type_info &= ~PGT_type_mask; page->u.inuse.type_info |= PGT_l1_page_table; - page->u.inuse.type_info |= - ((dsi.v_start>>L2_PAGETABLE_SHIFT)+(count-1))<>= L2_PAGETABLE_SHIFT; - vaddr <<= PGT_va_shift; - rc = get_page_and_type_from_pagenr( - l2e_get_pfn(l2e), PGT_l1_page_table | vaddr, d); + rc = get_page_and_type_from_pagenr(l2e_get_pfn(l2e), PGT_l1_page_table, d); #if CONFIG_PAGING_LEVELS == 2 if ( unlikely(!rc) ) rc = get_linear_pagetable(l2e, pfn, d); @@ -654,8 +650,7 @@ get_page_from_l2e( #if CONFIG_PAGING_LEVELS >= 3 static int get_page_from_l3e( - l3_pgentry_t l3e, unsigned long pfn, - struct domain *d, unsigned long vaddr) + l3_pgentry_t l3e, unsigned long pfn, struct domain *d) { int rc; @@ -668,11 +663,7 @@ get_page_from_l3e( return 0; } - vaddr >>= L3_PAGETABLE_SHIFT; - vaddr <<= PGT_va_shift; - rc = get_page_and_type_from_pagenr( - l3e_get_pfn(l3e), - PGT_l2_page_table | vaddr, d); + rc = get_page_and_type_from_pagenr(l3e_get_pfn(l3e), PGT_l2_page_table, d); return rc; } #endif /* 3 level */ @@ -680,8 +671,7 @@ get_page_from_l3e( #if CONFIG_PAGING_LEVELS >= 4 static int get_page_from_l4e( - l4_pgentry_t l4e, unsigned long pfn, - struct domain *d, unsigned long vaddr) + l4_pgentry_t l4e, unsigned long pfn, struct domain *d) { int rc; @@ -694,11 +684,7 @@ get_page_from_l4e( return 0; } - vaddr >>= L4_PAGETABLE_SHIFT; - vaddr <<= PGT_va_shift; - rc = get_page_and_type_from_pagenr( - l4e_get_pfn(l4e), - PGT_l3_page_table | vaddr, d); + rc = get_page_and_type_from_pagenr(l4e_get_pfn(l4e), PGT_l3_page_table, d); if ( unlikely(!rc) ) rc = get_linear_pagetable(l4e, pfn, d); @@ -877,8 +863,8 @@ static int create_pae_xen_mappings(l3_pgentry_t *pl3e) /* * The Xen-private mappings include linear mappings. The L2 thus cannot * be shared by multiple L3 tables. The test here is adequate because: - * 1. Cannot appear in slots != 3 because the page would then then have - * unknown va backpointer, which get_page_type() explicitly disallows. + * 1. Cannot appear in slots != 3 because get_page_type() checks the + * PGT_pae_xen_l2 flag, which is asserted iff the L2 appears in slot 3 * 2. Cannot appear in another page table's L3: * a. alloc_l3_table() calls this function and this check will fail * b. mod_l3_entry() disallows updates to slot 3 in an existing table @@ -888,6 +874,7 @@ static int create_pae_xen_mappings(l3_pgentry_t *pl3e) page = l3e_get_page(l3e3); BUG_ON(page->u.inuse.type_info & PGT_pinned); BUG_ON((page->u.inuse.type_info & PGT_count_mask) == 0); + BUG_ON(!(page->u.inuse.type_info & PGT_pae_xen_l2)); if ( (page->u.inuse.type_info & PGT_count_mask) != 1 ) { MEM_LOG("PAE L3 3rd slot is shared"); @@ -949,61 +936,17 @@ static void pae_flush_pgd( flush_tlb_mask(d->domain_dirty_cpumask); } -static inline int l1_backptr( - unsigned long *backptr, unsigned long offset_in_l2, unsigned long l2_type) -{ - unsigned long l2_backptr = l2_type & PGT_va_mask; - ASSERT(l2_backptr != PGT_va_unknown); - ASSERT(l2_backptr != PGT_va_mutable); - *backptr = - ((l2_backptr >> PGT_va_shift) << L3_PAGETABLE_SHIFT) | - (offset_in_l2 << L2_PAGETABLE_SHIFT); - return 1; -} - #elif CONFIG_X86_64 # define create_pae_xen_mappings(pl3e) (1) # define pae_flush_pgd(mfn, idx, nl3e) ((void)0) - -static inline int l1_backptr( - unsigned long *backptr, unsigned long offset_in_l2, unsigned long l2_type) -{ - unsigned long l2_backptr = l2_type & PGT_va_mask; - ASSERT(l2_backptr != PGT_va_unknown); - ASSERT(l2_backptr != PGT_va_mutable); - *backptr = ((l2_backptr >> PGT_va_shift) << L3_PAGETABLE_SHIFT) | - (offset_in_l2 << L2_PAGETABLE_SHIFT); - return 1; -} - -static inline int l2_backptr( - unsigned long *backptr, unsigned long offset_in_l3, unsigned long l3_type) -{ - unsigned long l3_backptr = l3_type & PGT_va_mask; - ASSERT(l3_backptr != PGT_va_unknown); - ASSERT(l3_backptr != PGT_va_mutable); - *backptr = ((l3_backptr >> PGT_va_shift) << L4_PAGETABLE_SHIFT) | - (offset_in_l3 << L3_PAGETABLE_SHIFT); - return 1; -} - -static inline int l3_backptr( - unsigned long *backptr, unsigned long offset_in_l4, unsigned long l4_type) -{ - *backptr = (offset_in_l4 << L4_PAGETABLE_SHIFT); - return 1; -} #else # define create_pae_xen_mappings(pl3e) (1) -# define l1_backptr(bp,l2o,l2t) \ - ({ *(bp) = (unsigned long)(l2o) << L2_PAGETABLE_SHIFT; 1; }) #endif static int alloc_l2_table(struct page_info *page, unsigned long type) { struct domain *d = page_get_owner(page); unsigned long pfn = page_to_mfn(page); - unsigned long vaddr; l2_pgentry_t *pl2e; int i; @@ -1013,10 +956,8 @@ static int alloc_l2_table(struct page_info *page, unsigned long type) for ( i = 0; i < L2_PAGETABLE_ENTRIES; i++ ) { - if ( !l1_backptr(&vaddr, i, type) ) - goto fail; if ( is_guest_l2_slot(type, i) && - unlikely(!get_page_from_l2e(pl2e[i], pfn, d, vaddr)) ) + unlikely(!get_page_from_l2e(pl2e[i], pfn, d)) ) goto fail; adjust_guest_l2e(pl2e[i]); @@ -1051,11 +992,10 @@ static int alloc_l2_table(struct page_info *page, unsigned long type) #if CONFIG_PAGING_LEVELS >= 3 -static int alloc_l3_table(struct page_info *page, unsigned long type) +static int alloc_l3_table(struct page_info *page) { struct domain *d = page_get_owner(page); unsigned long pfn = page_to_mfn(page); - unsigned long vaddr; l3_pgentry_t *pl3e; int i; @@ -1079,14 +1019,21 @@ static int alloc_l3_table(struct page_info *page, unsigned long type) pl3e = map_domain_page(pfn); for ( i = 0; i < L3_PAGETABLE_ENTRIES; i++ ) { -#if CONFIG_PAGING_LEVELS >= 4 - if ( !l2_backptr(&vaddr, i, type) ) - goto fail; -#else - vaddr = (unsigned long)i << L3_PAGETABLE_SHIFT; +#ifdef CONFIG_X86_PAE + if ( i == 3 ) + { + if ( !(l3e_get_flags(pl3e[i]) & _PAGE_PRESENT) || + (l3e_get_flags(pl3e[i]) & L3_DISALLOW_MASK) || + !get_page_and_type_from_pagenr(l3e_get_pfn(pl3e[i]), + PGT_l2_page_table | + PGT_pae_xen_l2, + d) ) + goto fail; + } + else #endif if ( is_guest_l3_slot(i) && - unlikely(!get_page_from_l3e(pl3e[i], pfn, d, vaddr)) ) + unlikely(!get_page_from_l3e(pl3e[i], pfn, d)) ) goto fail; adjust_guest_l3e(pl3e[i]); @@ -1108,27 +1055,23 @@ static int alloc_l3_table(struct page_info *page, unsigned long type) return 0; } #else -#define alloc_l3_table(page, type) (0) +#define alloc_l3_table(page) (0) #endif #if CONFIG_PAGING_LEVELS >= 4 -static int alloc_l4_table(struct page_info *page, unsigned long type) +static int alloc_l4_table(struct page_info *page) { struct domain *d = page_get_owner(page); unsigned long pfn = page_to_mfn(page); l4_pgentry_t *pl4e = page_to_virt(page); - unsigned long vaddr; int i; ASSERT(!shadow_mode_refcounts(d)); for ( i = 0; i < L4_PAGETABLE_ENTRIES; i++ ) { - if ( !l3_backptr(&vaddr, i, type) ) - goto fail; - if ( is_guest_l4_slot(i) && - unlikely(!get_page_from_l4e(pl4e[i], pfn, d, vaddr)) ) + unlikely(!get_page_from_l4e(pl4e[i], pfn, d)) ) goto fail; adjust_guest_l4e(pl4e[i]); @@ -1156,7 +1099,7 @@ static int alloc_l4_table(struct page_info *page, unsigned long type) return 0; } #else -#define alloc_l4_table(page, type) (0) +#define alloc_l4_table(page) (0) #endif @@ -1190,6 +1133,8 @@ static void free_l2_table(struct page_info *page) put_page_from_l2e(pl2e[i], pfn); unmap_domain_page(pl2e); + + page->u.inuse.type_info &= ~PGT_pae_xen_l2; } @@ -1357,7 +1302,6 @@ static int mod_l2_entry(l2_pgentry_t *pl2e, unsigned long type) { l2_pgentry_t ol2e; - unsigned long vaddr = 0; if ( unlikely(!is_guest_l2_slot(type,pgentry_ptr_to_slot(pl2e))) ) { @@ -1383,8 +1327,7 @@ static int mod_l2_entry(l2_pgentry_t *pl2e, if ( !l2e_has_changed(ol2e, nl2e, _PAGE_PRESENT)) return UPDATE_ENTRY(l2, pl2e, ol2e, nl2e, pfn); - if ( unlikely(!l1_backptr(&vaddr, pgentry_ptr_to_slot(pl2e), type)) || - unlikely(!get_page_from_l2e(nl2e, pfn, current->domain, vaddr)) ) + if ( unlikely(!get_page_from_l2e(nl2e, pfn, current->domain)) ) return 0; if ( unlikely(!UPDATE_ENTRY(l2, pl2e, ol2e, nl2e, pfn)) ) @@ -1407,11 +1350,9 @@ static int mod_l2_entry(l2_pgentry_t *pl2e, /* Update the L3 entry at pl3e to new value nl3e. pl3e is within frame pfn. */ static int mod_l3_entry(l3_pgentry_t *pl3e, l3_pgentry_t nl3e, - unsigned long pfn, - unsigned long type) + unsigned long pfn) { l3_pgentry_t ol3e; - unsigned long vaddr; int okay; if ( unlikely(!is_guest_l3_slot(pgentry_ptr_to_slot(pl3e))) ) @@ -1447,16 +1388,8 @@ static int mod_l3_entry(l3_pgentry_t *pl3e, if (!l3e_has_changed(ol3e, nl3e, _PAGE_PRESENT)) return UPDATE_ENTRY(l3, pl3e, ol3e, nl3e, pfn); -#if CONFIG_PAGING_LEVELS >= 4 - if ( unlikely(!l2_backptr(&vaddr, pgentry_ptr_to_slot(pl3e), type)) || - unlikely(!get_page_from_l3e(nl3e, pfn, current->domain, vaddr)) ) - return 0; -#else - vaddr = (((unsigned long)pl3e & ~PAGE_MASK) / sizeof(l3_pgentry_t)) - << L3_PAGETABLE_SHIFT; - if ( unlikely(!get_page_from_l3e(nl3e, pfn, current->domain, vaddr)) ) + if ( unlikely(!get_page_from_l3e(nl3e, pfn, current->domain)) ) return 0; -#endif if ( unlikely(!UPDATE_ENTRY(l3, pl3e, ol3e, nl3e, pfn)) ) { @@ -1485,11 +1418,9 @@ static int mod_l3_entry(l3_pgentry_t *pl3e, /* Update the L4 entry at pl4e to new value nl4e. pl4e is within frame pfn. */ static int mod_l4_entry(l4_pgentry_t *pl4e, l4_pgentry_t nl4e, - unsigned long pfn, - unsigned long type) + unsigned long pfn) { l4_pgentry_t ol4e; - unsigned long vaddr; if ( unlikely(!is_guest_l4_slot(pgentry_ptr_to_slot(pl4e))) ) { @@ -1515,8 +1446,7 @@ static int mod_l4_entry(l4_pgentry_t *pl4e, if (!l4e_has_changed(ol4e, nl4e, _PAGE_PRESENT)) return UPDATE_ENTRY(l4, pl4e, ol4e, nl4e, pfn); - if ( unlikely(!l3_backptr(&vaddr, pgentry_ptr_to_slot(pl4e), type)) || - unlikely(!get_page_from_l4e(nl4e, pfn, current->domain, vaddr)) ) + if ( unlikely(!get_page_from_l4e(nl4e, pfn, current->domain)) ) return 0; if ( unlikely(!UPDATE_ENTRY(l4, pl4e, ol4e, nl4e, pfn)) ) @@ -1550,9 +1480,9 @@ int alloc_page_type(struct page_info *page, unsigned long type) case PGT_l2_page_table: return alloc_l2_table(page, type); case PGT_l3_page_table: - return alloc_l3_table(page, type); + return alloc_l3_table(page); case PGT_l4_page_table: - return alloc_l4_table(page, type); + return alloc_l4_table(page); case PGT_gdt_page: case PGT_ldt_page: return alloc_segdesc_page(page); @@ -1672,12 +1602,6 @@ void put_page_type(struct page_info *page) /* Record TLB information for flush later. */ page->tlbflush_timestamp = tlbflush_current_time(); } - else if ( unlikely((nx & (PGT_pinned|PGT_type_mask|PGT_count_mask)) == - (PGT_pinned|PGT_l1_page_table|1)) ) - { - /* Page is now only pinned. Make the back pointer mutable again. */ - nx |= PGT_va_mutable; - } } while ( unlikely((y = cmpxchg(&page->u.inuse.type_info, x, nx)) != x) ); } @@ -1687,6 +1611,8 @@ int get_page_type(struct page_info *page, unsigned long type) { unsigned long nx, x, y = page->u.inuse.type_info; + ASSERT(!(type & ~(PGT_type_mask | PGT_pae_xen_l2))); + again: do { x = y; @@ -1698,29 +1624,26 @@ int get_page_type(struct page_info *page, unsigned long type) } else if ( unlikely((x & PGT_count_mask) == 0) ) { - if ( (x & (PGT_type_mask|PGT_va_mask)) != type ) + ASSERT(!(x & PGT_pae_xen_l2)); + if ( (x & PGT_type_mask) != type ) { - if ( (x & PGT_type_mask) != (type & PGT_type_mask) ) + /* + * On type change we check to flush stale TLB entries. This + * may be unnecessary (e.g., page was GDT/LDT) but those + * circumstances should be very rare. + */ + cpumask_t mask = + page_get_owner(page)->domain_dirty_cpumask; + tlbflush_filter(mask, page->tlbflush_timestamp); + + if ( unlikely(!cpus_empty(mask)) ) { - /* - * On type change we check to flush stale TLB - * entries. This may be unnecessary (e.g., page - * was GDT/LDT) but those circumstances should be - * very rare. - */ - cpumask_t mask = - page_get_owner(page)->domain_dirty_cpumask; - tlbflush_filter(mask, page->tlbflush_timestamp); - - if ( unlikely(!cpus_empty(mask)) ) - { - perfc_incrc(need_flush_tlb_flush); - flush_tlb_mask(mask); - } + perfc_incrc(need_flush_tlb_flush); + flush_tlb_mask(mask); } /* We lose existing type, back pointer, and validity. */ - nx &= ~(PGT_type_mask | PGT_va_mask | PGT_validated); + nx &= ~(PGT_type_mask | PGT_validated); nx |= type; /* No special validation needed for writable pages. */ @@ -1729,51 +1652,23 @@ int get_page_type(struct page_info *page, unsigned long type) nx |= PGT_validated; } } - else + else if ( unlikely((x & (PGT_type_mask|PGT_pae_xen_l2)) != type) ) { - if ( unlikely((x & (PGT_type_mask|PGT_va_mask)) != type) ) - { - if ( unlikely((x & PGT_type_mask) != (type & PGT_type_mask) ) ) - { - if ( ((x & PGT_type_mask) != PGT_l2_page_table) || - ((type & PGT_type_mask) != PGT_l1_page_table) ) - MEM_LOG("Bad type (saw %" PRtype_info - " != exp %" PRtype_info ") " - "for mfn %lx (pfn %lx)", - x, type, page_to_mfn(page), - get_gpfn_from_mfn(page_to_mfn(page))); - return 0; - } - else if ( (x & PGT_va_mask) == PGT_va_mutable ) - { - /* The va backpointer is mutable, hence we update it. */ - nx &= ~PGT_va_mask; - nx |= type; /* we know the actual type is correct */ - } - else if ( (type & PGT_va_mask) != PGT_va_mutable ) - { - ASSERT((type & PGT_va_mask) != (x & PGT_va_mask)); -#ifdef CONFIG_X86_PAE - /* We use backptr as extra typing. Cannot be unknown. */ - if ( (type & PGT_type_mask) == PGT_l2_page_table ) - return 0; -#endif - /* Fixme: add code to propagate va_unknown to subtables. */ - if ( ((type & PGT_type_mask) >= PGT_l2_page_table) && - !shadow_mode_refcounts(page_get_owner(page)) ) - return 0; - /* This table is possibly mapped at multiple locations. */ - nx &= ~PGT_va_mask; - nx |= PGT_va_unknown; - } - } - if ( unlikely(!(x & PGT_validated)) ) - { - /* Someone else is updating validation of this page. Wait... */ - while ( (y = page->u.inuse.type_info) == x ) - cpu_relax(); - goto again; - } + if ( ((x & PGT_type_mask) != PGT_l2_page_table) || + (type != PGT_l1_page_table) ) + MEM_LOG("Bad type (saw %" PRtype_info + " != exp %" PRtype_info ") " + "for mfn %lx (pfn %lx)", + x, type, page_to_mfn(page), + get_gpfn_from_mfn(page_to_mfn(page))); + return 0; + } + else if ( unlikely(!(x & PGT_validated)) ) + { + /* Someone else is updating validation of this page. Wait... */ + while ( (y = page->u.inuse.type_info) == x ) + cpu_relax(); + goto again; } } while ( unlikely((y = cmpxchg(&page->u.inuse.type_info, x, nx)) != x) ); @@ -2030,19 +1925,25 @@ int do_mmuext_op( switch ( op.cmd ) { case MMUEXT_PIN_L1_TABLE: - type = PGT_l1_page_table | PGT_va_mutable; + type = PGT_l1_page_table; goto pin_page; case MMUEXT_PIN_L2_TABLE: + type = PGT_l2_page_table; + goto pin_page; + case MMUEXT_PIN_L3_TABLE: - case MMUEXT_PIN_L4_TABLE: - /* Ignore pinning of subdirectories. */ - if ( (op.cmd - MMUEXT_PIN_L1_TABLE) != (CONFIG_PAGING_LEVELS - 1) ) - break; + type = PGT_l3_page_table; + goto pin_page; - type = PGT_root_page_table; + case MMUEXT_PIN_L4_TABLE: + type = PGT_l4_page_table; pin_page: + /* Ignore pinning of invalid paging levels. */ + if ( (op.cmd - MMUEXT_PIN_L1_TABLE) > (CONFIG_PAGING_LEVELS - 1) ) + break; + if ( shadow_mode_refcounts(FOREIGNDOM) ) break; @@ -2326,7 +2227,7 @@ int do_mmu_update( } if ( unlikely(!get_page_type( - page, type_info & (PGT_type_mask|PGT_va_mask))) ) + page, type_info & PGT_type_mask)) ) goto not_a_pt; switch ( type_info & PGT_type_mask ) @@ -2348,7 +2249,7 @@ int do_mmu_update( case PGT_l3_page_table: { l3_pgentry_t l3e = l3e_from_intpte(req.val); - okay = mod_l3_entry(va, l3e, mfn, type_info); + okay = mod_l3_entry(va, l3e, mfn); } break; #endif @@ -2356,7 +2257,7 @@ int do_mmu_update( case PGT_l4_page_table: { l4_pgentry_t l4e = l4e_from_intpte(req.val); - okay = mod_l4_entry(va, l4e, mfn, type_info); + okay = mod_l4_entry(va, l4e, mfn); } break; #endif @@ -2454,7 +2355,7 @@ static int create_grant_pte_mapping( void *va; unsigned long gmfn, mfn; struct page_info *page; - u32 type_info; + u32 type; l1_pgentry_t ol1e; struct domain *d = v->domain; @@ -2475,9 +2376,8 @@ static int create_grant_pte_mapping( va = (void *)((unsigned long)va + (pte_addr & ~PAGE_MASK)); page = mfn_to_page(mfn); - type_info = page->u.inuse.type_info; - if ( ((type_info & PGT_type_mask) != PGT_l1_page_table) || - !get_page_type(page, type_info & (PGT_type_mask|PGT_va_mask)) ) + type = page->u.inuse.type_info & PGT_type_mask; + if ( (type != PGT_l1_page_table) || !get_page_type(page, type) ) { MEM_LOG("Grant map attempted to update a non-L1 page"); rc = GNTST_general_error; @@ -2511,7 +2411,7 @@ static int destroy_grant_pte_mapping( void *va; unsigned long gmfn, mfn; struct page_info *page; - u32 type_info; + u32 type; l1_pgentry_t ol1e; gmfn = addr >> PAGE_SHIFT; @@ -2527,9 +2427,8 @@ static int destroy_grant_pte_mapping( va = (void *)((unsigned long)va + (addr & ~PAGE_MASK)); page = mfn_to_page(mfn); - type_info = page->u.inuse.type_info; - if ( ((type_info & PGT_type_mask) != PGT_l1_page_table) || - !get_page_type(page, type_info & (PGT_type_mask|PGT_va_mask)) ) + type = page->u.inuse.type_info & PGT_type_mask; + if ( (type != PGT_l1_page_table) || !get_page_type(page, type) ) { MEM_LOG("Grant map attempted to update a non-L1 page"); rc = GNTST_general_error; diff --git a/xen/arch/x86/mm/shadow/common.c b/xen/arch/x86/mm/shadow/common.c index 664b09f209..bdccf7a2d9 100644 --- a/xen/arch/x86/mm/shadow/common.c +++ b/xen/arch/x86/mm/shadow/common.c @@ -21,8 +21,6 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ -#define SHADOW 1 - #include #include #include @@ -225,7 +223,6 @@ struct x86_emulate_ops shadow_emulator_ops = { .cmpxchg8b_emulated = sh_x86_emulate_cmpxchg8b_emulated, }; - /**************************************************************************/ /* Code for "promoting" a guest page to the point where the shadow code is * willing to let it be treated as a guest page table. This generally @@ -235,7 +232,6 @@ struct x86_emulate_ops shadow_emulator_ops = { void shadow_promote(struct vcpu *v, mfn_t gmfn, u32 type) { struct page_info *page = mfn_to_page(gmfn); - unsigned long type_info; ASSERT(valid_mfn(gmfn)); @@ -251,10 +247,8 @@ void shadow_promote(struct vcpu *v, mfn_t gmfn, u32 type) // vcpu or not, or even what kind of type we get; we just want the type // count to be > 0. // - do { - type_info = - page->u.inuse.type_info & (PGT_type_mask | PGT_va_mask); - } while ( !get_page_type(page, type_info) ); + while ( !get_page_type(page, page->u.inuse.type_info & PGT_type_mask) ) + continue; // Now that the type ref is non-zero, we can safely use the // shadow_flags. diff --git a/xen/arch/x86/mm/shadow/multi.c b/xen/arch/x86/mm/shadow/multi.c index ace6a258f3..840c516fd6 100644 --- a/xen/arch/x86/mm/shadow/multi.c +++ b/xen/arch/x86/mm/shadow/multi.c @@ -35,8 +35,6 @@ // space for both PV and HVM guests. // -#define SHADOW 1 - #include #include #include diff --git a/xen/include/asm-ia64/mm.h b/xen/include/asm-ia64/mm.h index 111325936d..862b10176d 100644 --- a/xen/include/asm-ia64/mm.h +++ b/xen/include/asm-ia64/mm.h @@ -103,14 +103,6 @@ struct page_info #define _PGT_pinned 27 #define PGT_pinned (1U<<_PGT_pinned) - /* The 27 most significant bits of virt address if this is a page table. */ -#define PGT_va_shift 32 -#define PGT_va_mask ((unsigned long)((1U<<28)-1)<> PGT_va_shift) != 3) || \ + ( !((t) & PGT_pae_xen_l2) || \ ((s) < (L2_PAGETABLE_FIRST_XEN_SLOT & (L2_PAGETABLE_ENTRIES - 1))) ) #define is_guest_l3_slot(s) (1)