--- /dev/null
+From: jbeulich@novell.com
+Subject: don't require order-1 allocations for pgd-s
+Patch-mainline: obsolete
+
+At the same time remove the useless user mode pair of init_level4_pgt.
+
+--- sle11-2009-04-09.orig/arch/x86/kernel/cpu/common_64-xen.c 2008-11-17 14:07:10.000000000 +0100
++++ sle11-2009-04-09/arch/x86/kernel/cpu/common_64-xen.c 2009-03-16 16:40:52.000000000 +0100
+@@ -530,8 +530,7 @@ static void __init_refok switch_pt(int c
+ #ifdef CONFIG_XEN
+ if (cpu == 0)
+ xen_init_pt();
+- xen_pt_switch(__pa_symbol(init_level4_pgt));
+- xen_new_user_pt(__pa_symbol(__user_pgd(init_level4_pgt)));
++ xen_pt_switch(init_level4_pgt);
+ #endif
+ }
+
+--- sle11-2009-04-09.orig/arch/x86/kernel/head_64-xen.S 2009-03-16 16:38:16.000000000 +0100
++++ sle11-2009-04-09/arch/x86/kernel/head_64-xen.S 2009-03-16 16:40:52.000000000 +0100
+@@ -44,14 +44,6 @@ ENTRY(name)
+
+ NEXT_PAGE(init_level4_pgt)
+ .fill 512,8,0
+- /*
+- * We update two pgd entries to make kernel and user pgd consistent
+- * at pgd_populate(). It can be used for kernel modules. So we place
+- * this page here for those cases to avoid memory corruption.
+- * We also use this page to establish the initial mapping for the
+- * vsyscall area.
+- */
+- .fill 512,8,0
+
+ NEXT_PAGE(level3_kernel_pgt)
+ .fill 512,8,0
+--- sle11-2009-04-09.orig/arch/x86/mm/hypervisor.c 2009-03-16 16:40:50.000000000 +0100
++++ sle11-2009-04-09/arch/x86/mm/hypervisor.c 2009-03-30 12:19:20.000000000 +0200
+@@ -423,7 +423,7 @@ void xen_l3_entry_update(pud_t *ptr, pud
+ #endif
+
+ #ifdef CONFIG_X86_64
+-void xen_l4_entry_update(pgd_t *ptr, int user, pgd_t val)
++void xen_l4_entry_update(pgd_t *ptr, pgd_t val)
+ {
+ mmu_update_t u[2];
+ struct page *page = NULL;
+@@ -436,8 +436,10 @@ void xen_l4_entry_update(pgd_t *ptr, int
+ }
+ u[0].ptr = virt_to_machine(ptr);
+ u[0].val = __pgd_val(val);
+- if (user) {
+- u[1].ptr = virt_to_machine(__user_pgd(ptr));
++ if (((unsigned long)ptr & ~PAGE_MASK)
++ < pgd_index(__HYPERVISOR_VIRT_START) * sizeof(*ptr)
++ && (ptr = __user_pgd(ptr)) != NULL) {
++ u[1].ptr = virt_to_machine(ptr);
+ u[1].val = __pgd_val(val);
+ do_lN_entry_update(u, 2, page);
+ } else
+@@ -445,21 +447,25 @@ void xen_l4_entry_update(pgd_t *ptr, int
+ }
+ #endif /* CONFIG_X86_64 */
+
+-void xen_pt_switch(unsigned long ptr)
++#ifdef CONFIG_X86_64
++void xen_pt_switch(pgd_t *pgd)
+ {
+ struct mmuext_op op;
+ op.cmd = MMUEXT_NEW_BASEPTR;
+- op.arg1.mfn = pfn_to_mfn(ptr >> PAGE_SHIFT);
++ op.arg1.mfn = pfn_to_mfn(__pa(pgd) >> PAGE_SHIFT);
+ BUG_ON(HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF) < 0);
+ }
+
+-void xen_new_user_pt(unsigned long ptr)
++void xen_new_user_pt(pgd_t *pgd)
+ {
+ struct mmuext_op op;
++
++ pgd = __user_pgd(pgd);
+ op.cmd = MMUEXT_NEW_USER_BASEPTR;
+- op.arg1.mfn = pfn_to_mfn(ptr >> PAGE_SHIFT);
++ op.arg1.mfn = pgd ? pfn_to_mfn(__pa(pgd) >> PAGE_SHIFT) : 0;
+ BUG_ON(HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF) < 0);
+ }
++#endif
+
+ void xen_tlb_flush(void)
+ {
+@@ -529,28 +535,38 @@ void xen_invlpg_mask(cpumask_t *mask, un
+ void xen_pgd_pin(pgd_t *pgd)
+ {
+ struct mmuext_op op[NR_PGD_PIN_OPS];
++ unsigned int nr = NR_PGD_PIN_OPS;
+
+ op[0].cmd = MMUEXT_PIN_L3_TABLE;
+ op[0].arg1.mfn = pfn_to_mfn(__pa(pgd) >> PAGE_SHIFT);
+ #ifdef CONFIG_X86_64
+ op[1].cmd = op[0].cmd = MMUEXT_PIN_L4_TABLE;
+- op[1].arg1.mfn = pfn_to_mfn(__pa(__user_pgd(pgd)) >> PAGE_SHIFT);
++ pgd = __user_pgd(pgd);
++ if (pgd)
++ op[1].arg1.mfn = pfn_to_mfn(__pa(pgd) >> PAGE_SHIFT);
++ else
++ nr = 1;
+ #endif
+- if (HYPERVISOR_mmuext_op(op, NR_PGD_PIN_OPS, NULL, DOMID_SELF) < 0)
++ if (HYPERVISOR_mmuext_op(op, nr, NULL, DOMID_SELF) < 0)
+ BUG();
+ }
+
+ void xen_pgd_unpin(pgd_t *pgd)
+ {
+ struct mmuext_op op[NR_PGD_PIN_OPS];
++ unsigned int nr = NR_PGD_PIN_OPS;
+
+ op[0].cmd = MMUEXT_UNPIN_TABLE;
+ op[0].arg1.mfn = pfn_to_mfn(__pa(pgd) >> PAGE_SHIFT);
+ #ifdef CONFIG_X86_64
+- op[1].cmd = MMUEXT_UNPIN_TABLE;
+- op[1].arg1.mfn = pfn_to_mfn(__pa(__user_pgd(pgd)) >> PAGE_SHIFT);
++ pgd = __user_pgd(pgd);
++ if (pgd) {
++ op[1].cmd = MMUEXT_UNPIN_TABLE;
++ op[1].arg1.mfn = pfn_to_mfn(__pa(pgd) >> PAGE_SHIFT);
++ } else
++ nr = 1;
+ #endif
+- if (HYPERVISOR_mmuext_op(op, NR_PGD_PIN_OPS, NULL, DOMID_SELF) < 0)
++ if (HYPERVISOR_mmuext_op(op, nr, NULL, DOMID_SELF) < 0)
+ BUG();
+ }
+
+--- sle11-2009-04-09.orig/arch/x86/mm/init_64-xen.c 2009-03-16 16:40:50.000000000 +0100
++++ sle11-2009-04-09/arch/x86/mm/init_64-xen.c 2009-03-16 16:40:52.000000000 +0100
+@@ -616,9 +616,6 @@ void __init xen_init_pt(void)
+ __pud(__pa_symbol(level2_kernel_pgt) | _PAGE_TABLE);
+ memcpy(level2_kernel_pgt, page, PAGE_SIZE);
+
+- __user_pgd(init_level4_pgt)[pgd_index(VSYSCALL_START)] =
+- __pgd(__pa_symbol(level3_user_pgt) | _PAGE_TABLE);
+-
+ /* Do an early initialization of the fixmap area. */
+ addr = __fix_to_virt(FIX_EARLYCON_MEM_BASE);
+ level3_kernel_pgt[pud_index(addr)] =
+@@ -628,8 +625,6 @@ void __init xen_init_pt(void)
+
+ early_make_page_readonly(init_level4_pgt,
+ XENFEAT_writable_page_tables);
+- early_make_page_readonly(__user_pgd(init_level4_pgt),
+- XENFEAT_writable_page_tables);
+ early_make_page_readonly(level3_kernel_pgt,
+ XENFEAT_writable_page_tables);
+ early_make_page_readonly(level3_user_pgt,
+--- sle11-2009-04-09.orig/arch/x86/mm/pgtable-xen.c 2009-03-16 16:40:50.000000000 +0100
++++ sle11-2009-04-09/arch/x86/mm/pgtable-xen.c 2009-04-09 14:54:18.000000000 +0200
+@@ -270,9 +270,11 @@ static void pgd_walk(pgd_t *pgd_base, pg
+ BUG();
+ seq = 0;
+ }
++ pgd = __user_pgd(pgd_base);
++ BUG_ON(!pgd);
+ MULTI_update_va_mapping(mcl + seq,
+- (unsigned long)__user_pgd(pgd_base),
+- pfn_pte(virt_to_phys(__user_pgd(pgd_base))>>PAGE_SHIFT, flags),
++ (unsigned long)pgd,
++ pfn_pte(virt_to_phys(pgd)>>PAGE_SHIFT, flags),
+ 0);
+ MULTI_update_va_mapping(mcl + seq + 1,
+ (unsigned long)pgd_base,
+@@ -662,12 +664,29 @@ static void pgd_prepopulate_pmd(struct m
+ }
+ }
+
++static inline pgd_t *user_pgd_alloc(pgd_t *pgd)
++{
+ #ifdef CONFIG_X86_64
+-/* We allocate two contiguous pages for kernel and user. */
+-#define PGD_ORDER 1
+-#else
+-#define PGD_ORDER 0
++ if (pgd) {
++ pgd_t *upgd = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
++
++ if (upgd)
++ virt_to_page(pgd)->index = (long)upgd;
++ else {
++ free_page((unsigned long)pgd);
++ pgd = NULL;
++ }
++ }
++#endif
++ return pgd;
++}
++
++static inline void user_pgd_free(pgd_t *pgd)
++{
++#ifdef CONFIG_X86_64
++ free_page(virt_to_page(pgd)->index);
+ #endif
++}
+
+ pgd_t *pgd_alloc(struct mm_struct *mm)
+ {
+@@ -675,7 +694,7 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
+ pmd_t *pmds[PREALLOCATED_PMDS];
+ unsigned long flags;
+
+- pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, PGD_ORDER);
++ pgd = user_pgd_alloc((void *)__get_free_page(GFP_KERNEL|__GFP_ZERO));
+
+ if (pgd == NULL)
+ goto out;
+@@ -714,7 +733,8 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
+ out_free_pmds:
+ free_pmds(pmds, mm, !xen_feature(XENFEAT_pae_pgdir_above_4gb));
+ out_free_pgd:
+- free_pages((unsigned long)pgd, PGD_ORDER);
++ user_pgd_free(pgd);
++ free_page((unsigned long)pgd);
+ out:
+ return NULL;
+ }
+@@ -733,7 +753,8 @@ void pgd_free(struct mm_struct *mm, pgd_
+
+ pgd_mop_up_pmds(mm, pgd);
+ paravirt_pgd_free(mm, pgd);
+- free_pages((unsigned long)pgd, PGD_ORDER);
++ user_pgd_free(pgd);
++ free_page((unsigned long)pgd);
+ }
+
+ /* blktap and gntdev need this, as otherwise they would implicitly (and
+--- sle11-2009-04-09.orig/drivers/xen/core/machine_reboot.c 2009-02-17 12:25:29.000000000 +0100
++++ sle11-2009-04-09/drivers/xen/core/machine_reboot.c 2009-03-16 16:40:52.000000000 +0100
+@@ -191,8 +191,7 @@ static int take_machine_down(void *_susp
+ * in fast-suspend mode as that implies a new enough Xen.
+ */
+ if (!suspend->fast_suspend)
+- xen_new_user_pt(__pa(__user_pgd(
+- current->active_mm->pgd)));
++ xen_new_user_pt(current->active_mm->pgd);
+ #endif
+ }
+
+--- sle11-2009-04-09.orig/include/asm-x86/mach-xen/asm/hypervisor.h 2009-03-16 16:40:50.000000000 +0100
++++ sle11-2009-04-09/include/asm-x86/mach-xen/asm/hypervisor.h 2009-03-16 16:40:52.000000000 +0100
+@@ -85,8 +85,8 @@ void do_hypervisor_callback(struct pt_re
+ * be MACHINE addresses.
+ */
+
+-void xen_pt_switch(unsigned long ptr);
+-void xen_new_user_pt(unsigned long ptr); /* x86_64 only */
++void xen_pt_switch(pgd_t *);
++void xen_new_user_pt(pgd_t *); /* x86_64 only */
+ void xen_load_gs(unsigned int selector); /* x86_64 only */
+ void xen_tlb_flush(void);
+ void xen_invlpg(unsigned long ptr);
+@@ -94,7 +94,7 @@ void xen_invlpg(unsigned long ptr);
+ void xen_l1_entry_update(pte_t *ptr, pte_t val);
+ void xen_l2_entry_update(pmd_t *ptr, pmd_t val);
+ void xen_l3_entry_update(pud_t *ptr, pud_t val); /* x86_64/PAE */
+-void xen_l4_entry_update(pgd_t *ptr, int user, pgd_t val); /* x86_64 only */
++void xen_l4_entry_update(pgd_t *ptr, pgd_t val); /* x86_64 only */
+ void xen_pgd_pin(pgd_t *);
+ void xen_pgd_unpin(pgd_t *);
+
+--- sle11-2009-04-09.orig/include/asm-x86/mach-xen/asm/mmu_context_64.h 2009-03-16 16:38:16.000000000 +0100
++++ sle11-2009-04-09/include/asm-x86/mach-xen/asm/mmu_context_64.h 2009-03-16 16:40:52.000000000 +0100
+@@ -46,6 +46,7 @@ static inline void switch_mm(struct mm_s
+ {
+ unsigned cpu = smp_processor_id();
+ struct mmuext_op _op[3], *op = _op;
++ pgd_t *upgd;
+
+ if (likely(prev != next)) {
+ BUG_ON(!xen_feature(XENFEAT_writable_page_tables) &&
+@@ -64,9 +65,11 @@ static inline void switch_mm(struct mm_s
+ op->arg1.mfn = pfn_to_mfn(__pa(next->pgd) >> PAGE_SHIFT);
+ op++;
+
+- /* xen_new_user_pt(__pa(__user_pgd(next->pgd))) */
++ /* xen_new_user_pt(next->pgd) */
+ op->cmd = MMUEXT_NEW_USER_BASEPTR;
+- op->arg1.mfn = pfn_to_mfn(__pa(__user_pgd(next->pgd)) >> PAGE_SHIFT);
++ upgd = __user_pgd(next->pgd);
++ op->arg1.mfn = likely(upgd)
++ ? pfn_to_mfn(__pa(upgd) >> PAGE_SHIFT) : 0;
+ op++;
+
+ if (unlikely(next->context.ldt != prev->context.ldt)) {
+@@ -90,7 +93,7 @@ static inline void switch_mm(struct mm_s
+ * to make sure to use no freed page tables.
+ */
+ load_cr3(next->pgd);
+- xen_new_user_pt(__pa(__user_pgd(next->pgd)));
++ xen_new_user_pt(next->pgd);
+ load_LDT_nolock(&next->context);
+ }
+ }
+--- sle11-2009-04-09.orig/include/asm-x86/mach-xen/asm/pgalloc.h 2009-03-16 16:40:37.000000000 +0100
++++ sle11-2009-04-09/include/asm-x86/mach-xen/asm/pgalloc.h 2009-03-16 16:40:52.000000000 +0100
+@@ -106,15 +106,13 @@ static inline void pud_populate(struct m
+ #endif /* CONFIG_X86_PAE */
+
+ #if PAGETABLE_LEVELS > 3
+-#define __user_pgd(pgd) ((pgd) + PTRS_PER_PGD)
+-
+ static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
+ {
+ pgd_t ent = __pgd(_PAGE_TABLE | __pa(pud));
+
+ paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
+ if (unlikely(PagePinned(virt_to_page(pgd))))
+- xen_l4_entry_update(pgd, 1, ent);
++ xen_l4_entry_update(pgd, ent);
+ else
+ *__user_pgd(pgd) = *pgd = ent;
+ }
+--- sle11-2009-04-09.orig/include/asm-x86/mach-xen/asm/pgtable_64.h 2009-03-16 16:40:37.000000000 +0100
++++ sle11-2009-04-09/include/asm-x86/mach-xen/asm/pgtable_64.h 2009-03-16 16:40:52.000000000 +0100
+@@ -131,18 +131,25 @@ static inline void xen_set_pud(pud_t *pu
+ : (void)(*__pudp = xen_make_pud(0)); \
+ })
+
+-#define __user_pgd(pgd) ((pgd) + PTRS_PER_PGD)
++static inline pgd_t *__user_pgd(pgd_t *pgd)
++{
++ if (unlikely(((unsigned long)pgd & PAGE_MASK)
++ == (unsigned long)init_level4_pgt))
++ return NULL;
++ return (pgd_t *)(virt_to_page(pgd)->index
++ + ((unsigned long)pgd & ~PAGE_MASK));
++}
+
+ static inline void xen_set_pgd(pgd_t *pgdp, pgd_t pgd)
+ {
+- xen_l4_entry_update(pgdp, 0, pgd);
++ xen_l4_entry_update(pgdp, pgd);
+ }
+
+ #define xen_pgd_clear(pgd) \
+ ({ \
+ pgd_t *__pgdp = (pgd); \
+ PagePinned(virt_to_page(__pgdp)) \
+- ? xen_l4_entry_update(__pgdp, 1, xen_make_pgd(0)) \
++ ? xen_l4_entry_update(__pgdp, xen_make_pgd(0)) \
+ : (void)(*__user_pgd(__pgdp) = *__pgdp = xen_make_pgd(0)); \
+ })
+
projects / people / teissler / ipfire-2.x.git / blobdiff