Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756554AbYAWQPy (ORCPT ); Wed, 23 Jan 2008 11:15:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752677AbYAWQPo (ORCPT ); Wed, 23 Jan 2008 11:15:44 -0500 Received: from smtp-out.google.com ([216.239.33.17]:58631 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752775AbYAWQPm (ORCPT ); Wed, 23 Jan 2008 11:15:42 -0500 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=received:to:subject:message-id:date:from; b=p8wpaPTr0Zepu38JNXlbmFyoFY7ym/XR35DyzSWyfYmgK/rWu1YaG8Zf4Qe/TUz33 YCJPEZMxhzHpcVqKwwM2A== To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, rossb@google.com Subject: [RFC][PATCH 2/2]: MM: Make Page Tables Relocatable Message-Id: <20080123161441.2A535DCA00@localhost> Date: Wed, 23 Jan 2008 08:14:41 -0800 (PST) From: rossb@google.com (Ross Biro) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 26817 Lines: 913 --- diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/arch/i386/mm/hugetlbpage.c 2.6.23a/arch/i386/mm/hugetlbpage.c --- 2.6.23/arch/i386/mm/hugetlbpage.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/arch/i386/mm/hugetlbpage.c 2007-10-29 09:48:48.000000000 -0700 @@ -87,6 +87,7 @@ static void huge_pmd_share(struct mm_str goto out; spin_lock(&mm->page_table_lock); + delimbo_pud(&pud, mm, addr); if (pud_none(*pud)) pud_populate(mm, pud, (unsigned long) spte & PAGE_MASK); else diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/arch/powerpc/mm/fault.c 2.6.23a/arch/powerpc/mm/fault.c --- 2.6.23/arch/powerpc/mm/fault.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/arch/powerpc/mm/fault.c 2007-10-29 09:38:09.000000000 -0700 @@ -301,6 +301,8 @@ good_area: if (get_pteptr(mm, address, &ptep, &pmdp)) { spinlock_t *ptl = pte_lockptr(mm, pmdp); spin_lock(ptl); + delimbo_pte(&ptep, &ptl, &pmdp, mm, address); + if (pte_present(*ptep)) { struct page *page = pte_page(*ptep); diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/arch/powerpc/mm/hugetlbpage.c 2.6.23a/arch/powerpc/mm/hugetlbpage.c --- 2.6.23/arch/powerpc/mm/hugetlbpage.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/arch/powerpc/mm/hugetlbpage.c 2007-10-29 09:53:36.000000000 -0700 @@ -77,6 +77,7 @@ static int __hugepte_alloc(struct mm_str return -ENOMEM; spin_lock(&mm->page_table_lock); + delimbo_hpd(&hpdp, mm, address); if (!hugepd_none(*hpdp)) kmem_cache_free(huge_pgtable_cache, new); else diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/arch/ppc/mm/fault.c 2.6.23a/arch/ppc/mm/fault.c --- 2.6.23/arch/ppc/mm/fault.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/arch/ppc/mm/fault.c 2007-10-29 09:38:19.000000000 -0700 @@ -219,6 +219,7 @@ good_area: if (get_pteptr(mm, address, &ptep, &pmdp)) { spinlock_t *ptl = pte_lockptr(mm, pmdp); spin_lock(ptl); + delimbo_pte(&ptep, &ptl, &pmdp, mm, address); if (pte_present(*ptep)) { struct page *page = pte_page(*ptep); diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/arch/x86_64/kernel/smp.c 2.6.23a/arch/x86_64/kernel/smp.c --- 2.6.23/arch/x86_64/kernel/smp.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/arch/x86_64/kernel/smp.c 2008-01-14 10:46:49.000000000 -0800 @@ -56,6 +56,7 @@ union smp_flush_state { struct mm_struct *flush_mm; unsigned long flush_va; #define FLUSH_ALL -1ULL +#define RELOAD_ALL -2ULL spinlock_t tlbstate_lock; }; char pad[SMP_CACHE_BYTES]; @@ -155,6 +156,8 @@ asmlinkage void smp_invalidate_interrupt if (read_pda(mmu_state) == TLBSTATE_OK) { if (f->flush_va == FLUSH_ALL) local_flush_tlb(); + else if (f->flush_va == RELOAD_ALL) + local_reload_tlb_mm(f->flush_mm); else __flush_tlb_one(f->flush_va); } else @@ -225,10 +228,36 @@ void flush_tlb_current_task(void) } EXPORT_SYMBOL(flush_tlb_current_task); +void reload_tlb_mm(struct mm_struct *mm) +{ + cpumask_t cpu_mask; + + clear_bit(MMF_NEED_RELOAD, &mm->flags); + clear_bit(MMF_NEED_FLUSH, &mm->flags); + + preempt_disable(); + cpu_mask = mm->cpu_vm_mask; + cpu_clear(smp_processor_id(), cpu_mask); + + if (current->active_mm == mm) { + if (current->mm) + local_reload_tlb_mm(mm); + else + leave_mm(smp_processor_id()); + } + if (!cpus_empty(cpu_mask)) + flush_tlb_others(cpu_mask, mm, RELOAD_ALL); + + preempt_enable(); + +} + void flush_tlb_mm (struct mm_struct * mm) { cpumask_t cpu_mask; + clear_bit(MMF_NEED_FLUSH, &mm->flags); + preempt_disable(); cpu_mask = mm->cpu_vm_mask; cpu_clear(smp_processor_id(), cpu_mask); diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/include/asm-generic/pgtable.h 2.6.23a/include/asm-generic/pgtable.h --- 2.6.23/include/asm-generic/pgtable.h 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/include/asm-generic/pgtable.h 2008-01-08 08:00:34.000000000 -0800 @@ -4,6 +4,8 @@ #ifndef __ASSEMBLY__ #ifdef CONFIG_MMU +#include + #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS /* * Largely same as above, but only sets the access flags (dirty, @@ -199,6 +201,49 @@ static inline int pmd_none_or_clear_bad( } return 0; } + + +/* Used to rewalk the page tables if after we grab the appropriate lock, + we end up with a page that's just waiting to go away. */ +static inline pgd_t *walk_page_table_pgd(struct mm_struct *mm, + unsigned long addr) +{ + return pgd_offset(mm, addr); +} + +static inline pud_t *walk_page_table_pud(struct mm_struct *mm, + unsigned long addr) { + pgd_t *pgd; + pgd = walk_page_table_pgd(mm, addr); + BUG_ON(!pgd); + return pud_offset(pgd, addr); +} + +static inline pmd_t *walk_page_table_pmd(struct mm_struct *mm, + unsigned long addr) +{ + pud_t *pud; + pud = walk_page_table_pud(mm, addr); + BUG_ON(!pud); + return pmd_offset(pud, addr); +} + +static inline pte_t *walk_page_table_pte(struct mm_struct *mm, + unsigned long addr) +{ + pmd_t *pmd; + pmd = walk_page_table_pmd(mm, addr); + BUG_ON(!pmd); + return pte_offset_map(pmd, addr); +} + +static inline pte_t *walk_page_table_huge_pte(struct mm_struct *mm, + unsigned long addr) +{ + return (pte_t *)walk_page_table_pmd(mm, addr); +} + + #endif /* CONFIG_MMU */ /* diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/include/asm-x86_64/tlbflush.h 2.6.23a/include/asm-x86_64/tlbflush.h --- 2.6.23/include/asm-x86_64/tlbflush.h 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/include/asm-x86_64/tlbflush.h 2008-01-11 08:31:06.000000000 -0800 @@ -6,6 +6,13 @@ #include #include +#define ARCH_HAS_RELOAD_TLB +static inline void load_cr3(pgd_t *pgd); +static inline void __reload_tlb_mm(struct mm_struct *mm) +{ + load_cr3(mm->pgd); +} + static inline void __flush_tlb(void) { write_cr3(read_cr3()); @@ -44,6 +50,12 @@ static inline void __flush_tlb_all(void) #define flush_tlb_all() __flush_tlb_all() #define local_flush_tlb() __flush_tlb() +static inline void reload_tlb_mm(struct mm_struct *mm) +{ + if (mm == current->active_mm) + __reload_tlb_mm(mm); +} + static inline void flush_tlb_mm(struct mm_struct *mm) { if (mm == current->active_mm) @@ -71,6 +83,10 @@ static inline void flush_tlb_range(struc #define local_flush_tlb() \ __flush_tlb() +#define local_reload_tlb_mm(mm) \ + __reload_tlb_mm(mm) + +extern void reload_tlb_mm(struct mm_struct *mm); extern void flush_tlb_all(void); extern void flush_tlb_current_task(void); extern void flush_tlb_mm(struct mm_struct *); @@ -106,4 +122,6 @@ static inline void flush_tlb_pgtables(st by the normal TLB flushing algorithms. */ } +#include + #endif /* _X8664_TLBFLUSH_H */ diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/include/linux/mm.h 2.6.23a/include/linux/mm.h --- 2.6.23/include/linux/mm.h 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/include/linux/mm.h 2008-01-02 08:07:47.000000000 -0800 @@ -14,6 +14,7 @@ #include #include #include +#include struct mempolicy; struct anon_vma; @@ -935,6 +936,7 @@ static inline pmd_t *pmd_alloc(struct mm pte_t *__pte = pte_offset_map(pmd, address); \ *(ptlp) = __ptl; \ spin_lock(__ptl); \ + delimbo_pte(&__pte, ptlp, &pmd, mm, address); \ __pte; \ }) @@ -959,6 +962,62 @@ extern void free_area_init(unsigned long extern void free_area_init_node(int nid, pg_data_t *pgdat, unsigned long * zones_size, unsigned long zone_start_pfn, unsigned long *zholes_size); + + + +static inline void delimbo_pte(pte_t **pte, spinlock_t **ptl, pmd_t **pmd, + struct mm_struct *mm, + unsigned long addr) +{ +#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS + spin_unlock(*ptl); +#endif + pte_unmap(*pte); + *pmd = walk_page_table_pmd(mm, addr); + *pte = pte_offset_map(*pmd, addr); + *ptl = pte_lockptr(mm, *pmd); +#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS + spin_lock(*ptl); +#endif +} + +static inline void delimbo_pte_nested(pte_t **pte, spinlock_t **ptl, + pmd_t **pmd, + struct mm_struct *mm, + unsigned long addr, int subclass) +{ +#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS + spin_unlock(*ptl); +#endif + *pmd = walk_page_table_pmd(mm, addr); + *pte = pte_offset_map(*pmd, addr); + *ptl = pte_lockptr(mm, *pmd); + +#if NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS + spin_lock_nested(*ptl, subclass); +#endif +} + +static inline void delimbo_pud(pud_t **pud, struct mm_struct *mm, + unsigned long addr) { + *pud = walk_page_table_pud(mm, addr); +} + +static inline void delimbo_pmd(pmd_t **pmd, struct mm_struct *mm, + unsigned long addr) { + *pmd = walk_page_table_pmd(mm, addr); +} + +static inline void delimbo_pgd(pgd_t **pgd, struct mm_struct *mm, + unsigned long addr) { + *pgd = walk_page_table_pgd(mm, addr); +} + +static inline void delimbo_huge_pte(pte_t **pte, struct mm_struct *mm, + unsigned long addr) { + *pte = walk_page_table_huge_pte(mm, addr); +} + #ifdef CONFIG_ARCH_POPULATES_NODE_MAP /* * With CONFIG_ARCH_POPULATES_NODE_MAP set, an architecture may initialise its diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/include/linux/mm_types.h 2.6.23a/include/linux/mm_types.h --- 2.6.23/include/linux/mm_types.h 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/include/linux/mm_types.h 2008-01-02 08:06:09.000000000 -0800 @@ -5,6 +5,7 @@ #include #include #include +#include struct address_space; @@ -61,9 +62,18 @@ struct page { pgoff_t index; /* Our offset within mapping. */ void *freelist; /* SLUB: freelist req. slab lock */ }; + + union { struct list_head lru; /* Pageout list, eg. active_list * protected by zone->lru_lock ! */ + struct rcu_head rcu; /* Used by page table relocation code + * to remember page for later freeing, + * after we are sure anyone + * poking at the page tables is no + * longer looking at this page. + */ + }; /* * On machines where all RAM is mapped into kernel address space, * we can simply calculate the virtual address. On machines with diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/mm/hugetlb.c 2.6.23a/mm/hugetlb.c --- 2.6.23/mm/hugetlb.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/mm/hugetlb.c 2007-10-30 07:32:50.000000000 -0700 @@ -379,6 +379,8 @@ int copy_hugetlb_page_range(struct mm_st goto nomem; spin_lock(&dst->page_table_lock); spin_lock(&src->page_table_lock); + delimbo_huge_pte(&src_pte, src, addr); + delimbo_huge_pte(&dst_pte, dst, addr); if (!pte_none(*src_pte)) { if (cow) ptep_set_wrprotect(src, addr, src_pte); @@ -551,6 +553,7 @@ retry: } spin_lock(&mm->page_table_lock); + delimbo_huge_pte(&ptep, mm, address); size = i_size_read(mapping->host) >> HPAGE_SHIFT; if (idx >= size) goto backout; @@ -609,6 +612,7 @@ int hugetlb_fault(struct mm_struct *mm, ret = 0; spin_lock(&mm->page_table_lock); + delimbo_huge_pte(&ptep, mm, address); /* Check for a racing update before calling hugetlb_cow */ if (likely(pte_same(entry, *ptep))) if (write_access && !pte_write(entry)) diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/mm/memory.c 2.6.23a/mm/memory.c --- 2.6.23/mm/memory.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/mm/memory.c 2008-01-11 10:50:42.000000000 -0800 @@ -306,6 +306,7 @@ int __pte_alloc(struct mm_struct *mm, pm pte_lock_init(new); spin_lock(&mm->page_table_lock); + delimbo_pmd(&pmd, mm, address); if (pmd_present(*pmd)) { /* Another has populated it */ pte_lock_deinit(new); pte_free(new); @@ -325,6 +326,7 @@ int __pte_alloc_kernel(pmd_t *pmd, unsig return -ENOMEM; spin_lock(&init_mm.page_table_lock); + delimbo_pmd(&pmd, &init_mm, address); if (pmd_present(*pmd)) /* Another has populated it */ pte_free_kernel(new); else @@ -504,6 +506,8 @@ again: src_pte = pte_offset_map_nested(src_pmd, addr); src_ptl = pte_lockptr(src_mm, src_pmd); spin_lock_nested(src_ptl, SINGLE_DEPTH_NESTING); + + delimbo_pte(&src_pte, &src_ptl, &src_pmd, src_mm, addr); arch_enter_lazy_mmu_mode(); do { @@ -1558,13 +1562,15 @@ EXPORT_SYMBOL_GPL(apply_to_page_range); * and do_anonymous_page and do_no_page can safely check later on). */ static inline int pte_unmap_same(struct mm_struct *mm, pmd_t *pmd, - pte_t *page_table, pte_t orig_pte) + pte_t *page_table, pte_t orig_pte, + unsigned long address) { int same = 1; #if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT) if (sizeof(pte_t) > sizeof(unsigned long)) { spinlock_t *ptl = pte_lockptr(mm, pmd); spin_lock(ptl); + delimbo_pte(&page_table, &ptl, &pmd, mm, address); same = pte_same(*page_table, orig_pte); spin_unlock(ptl); } @@ -2153,7 +2159,7 @@ static int do_swap_page(struct mm_struct pte_t pte; int ret = 0; - if (!pte_unmap_same(mm, pmd, page_table, orig_pte)) + if (!pte_unmap_same(mm, pmd, page_table, orig_pte, address)) goto out; entry = pte_to_swp_entry(orig_pte); @@ -2227,6 +2233,10 @@ static int do_swap_page(struct mm_struct } /* No need to invalidate - it was non-present before */ + /* Unless of course the cpu might be looking at an old + copy of the pte. */ + maybe_reload_tlb_mm(mm); + update_mmu_cache(vma, address, pte); unlock: pte_unmap_unlock(page_table, ptl); @@ -2279,6 +2289,7 @@ static int do_anonymous_page(struct mm_s ptl = pte_lockptr(mm, pmd); spin_lock(ptl); + delimbo_pte(&page_table, &ptl, &pmd, mm, address); if (!pte_none(*page_table)) goto release; inc_mm_counter(mm, file_rss); @@ -2288,6 +2299,10 @@ static int do_anonymous_page(struct mm_s set_pte_at(mm, address, page_table, entry); /* No need to invalidate - it was non-present before */ + /* Unless of course the cpu might be looking at an old + copy of the pte. */ + maybe_reload_tlb_mm(mm); + update_mmu_cache(vma, address, entry); lazy_mmu_prot_update(entry); unlock: @@ -2441,6 +2456,10 @@ static int __do_fault(struct mm_struct * } /* no need to invalidate: a not-present page won't be cached */ + /* Unless of course the cpu could be looking at an old page + table entry. */ + maybe_reload_tlb_mm(mm); + update_mmu_cache(vma, address, entry); lazy_mmu_prot_update(entry); } else { @@ -2544,7 +2563,7 @@ static int do_nonlinear_fault(struct mm_ (write_access ? FAULT_FLAG_WRITE : 0); pgoff_t pgoff; - if (!pte_unmap_same(mm, pmd, page_table, orig_pte)) + if (!pte_unmap_same(mm, pmd, page_table, orig_pte, address)) return 0; if (unlikely(!(vma->vm_flags & VM_NONLINEAR) || @@ -2603,6 +2622,7 @@ static inline int handle_pte_fault(struc ptl = pte_lockptr(mm, pmd); spin_lock(ptl); + delimbo_pte(&pte, &ptl, &pmd, mm, address); if (unlikely(!pte_same(*pte, entry))) goto unlock; if (write_access) { @@ -2625,6 +2645,12 @@ static inline int handle_pte_fault(struc if (write_access) flush_tlb_page(vma, address); } + + /* if the cpu could be looking at an old page table, we need to + flush out everything. */ + maybe_reload_tlb_mm(mm); + + unlock: pte_unmap_unlock(pte, ptl); return 0; @@ -2674,6 +2700,7 @@ int __pud_alloc(struct mm_struct *mm, pg return -ENOMEM; spin_lock(&mm->page_table_lock); + delimbo_pgd(&pgd, mm, address); if (pgd_present(*pgd)) /* Another has populated it */ pud_free(new); else @@ -2695,6 +2722,7 @@ int __pmd_alloc(struct mm_struct *mm, pu return -ENOMEM; spin_lock(&mm->page_table_lock); + delimbo_pud(&pud, mm, address); #ifndef __ARCH_HAS_4LEVEL_HACK if (pud_present(*pud)) /* Another has populated it */ pmd_free(new); diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/mm/mempolicy.c 2.6.23a/mm/mempolicy.c --- 2.6.23/mm/mempolicy.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/mm/mempolicy.c 2008-01-11 10:04:11.000000000 -0800 @@ -101,6 +101,11 @@ static struct kmem_cache *policy_cache; static struct kmem_cache *sn_cache; + +int migrate_page_tables_mm(struct mm_struct *mm, int source, + new_page_t get_new_page, unsigned long private); + + /* Highest zone. An specific allocation for a zone below that is not policied. */ enum zone_type policy_zone = 0; @@ -597,6 +602,11 @@ static struct page *new_node_page(struct return alloc_pages_node(node, GFP_HIGHUSER_MOVABLE, 0); } +static struct page *new_node_page_page_tables(struct page *page, + unsigned long node, int **x) { + return alloc_pages_node(node, GFP_KERNEL, 0); +} + /* * Migrate pages from one node to a target node. * Returns error or the number of pages not migrated. @@ -616,6 +626,10 @@ int migrate_to_node(struct mm_struct *mm if (!list_empty(&pagelist)) err = migrate_pages(&pagelist, new_node_page, dest); + if (!err) + err = migrate_page_tables_mm(mm, source, + new_node_page_page_tables, dest); + return err; } diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/mm/migrate.c 2.6.23a/mm/migrate.c --- 2.6.23/mm/migrate.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/mm/migrate.c 2008-01-17 07:37:21.000000000 -0800 @@ -28,9 +28,15 @@ #include #include #include - +#include +#include +#include +#include #include "internal.h" +int migrate_page_tables_mm(struct mm_struct *mm, int source, + new_page_t get_new_page, unsigned long private); + #define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru)) /* @@ -158,6 +164,7 @@ static void remove_migration_pte(struct ptl = pte_lockptr(mm, pmd); spin_lock(ptl); + delimbo_pte(&ptep, &ptl, &pmd, mm, addr); pte = *ptep; if (!is_swap_pte(pte)) goto out; @@ -859,9 +866,10 @@ set_status: err = migrate_pages(&pagelist, new_page_node, (unsigned long)pm); else - err = -ENOENT; + err = 0; up_read(&mm->mmap_sem); + return err; } @@ -1039,3 +1047,312 @@ int migrate_vmas(struct mm_struct *mm, c } return err; } + +static void rcu_free_pt(struct rcu_head *head) +{ + /* Need to know that the mm has been flushed before + * we get here. Otherwise we need a way to find + * the appropriate mm to flush. + */ + struct page *page = container_of(head, struct page, rcu); + __free_page(page); +} + +int migrate_pgd(pgd_t *pgd, struct mm_struct *mm, + unsigned long addr, struct page *dest, + struct list_head *old_pages) +{ + unsigned long flags; + void *dest_ptr; + pud_t *pud; + + spin_lock_irqsave(&mm->page_table_lock, flags); + + delimbo_pgd(&pgd, mm, addr); + + pud = pud_offset(pgd, addr); + dest_ptr = page_address(dest); + memcpy(dest_ptr, pud, PAGE_SIZE); + + list_add_tail(&(pgd_page(*pgd)->lru), old_pages); + pgd_populate(mm, pgd, dest_ptr); + + flush_tlb_pgtables(mm, addr, + addr + (1 << PMD_SHIFT) + - 1); + + maybe_need_flush_mm(mm); + + spin_unlock_irqrestore(&mm->page_table_lock, flags); + + return 0; + +} + +int migrate_pud(pud_t *pud, struct mm_struct *mm, unsigned long addr, + struct page *dest, struct list_head *old_pages) +{ + unsigned long flags; + void *dest_ptr; + pmd_t *pmd; + + spin_lock_irqsave(&mm->page_table_lock, flags); + + delimbo_pud(&pud, mm, addr); + pmd = pmd_offset(pud, addr); + + dest_ptr = page_address(dest); + memcpy(dest_ptr, pmd, PAGE_SIZE); + + list_add_tail(&(pud_page(*pud)->lru), old_pages); + + pud_populate(mm, pud, dest_ptr); + flush_tlb_pgtables(mm, addr, + addr + (1 << PMD_SHIFT) + - 1); + maybe_need_flush_mm(mm); + + spin_unlock_irqrestore(&mm->page_table_lock, flags); + + return 0; +} + + +int migrate_pmd(pmd_t *pmd, struct mm_struct *mm, unsigned long addr, + struct page *dest, struct list_head *old_pages) +{ + unsigned long flags; + void *dest_ptr; + spinlock_t *ptl; + pte_t *pte; + + spin_lock_irqsave(&mm->page_table_lock, flags); + + delimbo_pmd(&pmd, mm, addr); + + /* this could happen if the page table has been swapped out and we + were looking at the old one. */ + if (unlikely(!pmd_present(*pmd))) { + spin_unlock_irqrestore(&mm->page_table_lock, flags); + return 1; + } + + ptl = pte_lockptr(mm, pmd); + + /* We need the page lock as well. */ + if (ptl != &mm->page_table_lock) + spin_lock(ptl); + + pte = pte_offset_map(pmd, addr); + + dest_ptr = kmap_atomic(dest, KM_USER0); + memcpy(dest_ptr, pte, PAGE_SIZE); + list_add_tail(&(pmd_page(*pmd)->lru), old_pages); + + kunmap_atomic(dest, KM_USER0); + pte_unmap(pte); + pte_lock_init(dest); + pmd_populate(NULL, pmd, dest); + flush_tlb_pgtables(mm, addr, + addr + (1 << PMD_SHIFT) + - 1); + maybe_need_flush_mm(mm); + + if (ptl != &mm->page_table_lock) + spin_unlock(ptl); + + spin_unlock_irqrestore(&mm->page_table_lock, flags); + + return 0; +} + +static int migrate_page_tables_pmd(pmd_t *pmd, struct mm_struct *mm, + unsigned long *address, int source, + new_page_t get_new_page, + unsigned long private, + struct list_head *old_pages) +{ + int pages_not_migrated = 0; + int *result = NULL; + struct page *old_page = virt_to_page(pmd); + struct page *new_page; + int not_migrated; + + if (!pmd_present(*pmd)) { + *address += (unsigned long)PTRS_PER_PTE * PAGE_SIZE; + return 0; + } + + if (page_to_nid(old_page) == source) { + new_page = get_new_page(old_page, private, &result); + if (!new_page) + return -ENOMEM; + not_migrated = migrate_pmd(pmd, mm, *address, new_page, + old_pages); + if (not_migrated) + __free_page(new_page); + + pages_not_migrated += not_migrated; + } + *address += (unsigned long)PTRS_PER_PTE * PAGE_SIZE; + + return pages_not_migrated; +} + +static int migrate_page_tables_pud(pud_t *pud, struct mm_struct *mm, + unsigned long *address, int source, + new_page_t get_new_page, + unsigned long private, + struct list_head *old_pages) +{ + int pages_not_migrated = 0; + int i; + int *result = NULL; + struct page *old_page = virt_to_page(pud); + struct page *new_page; + int not_migrated; + + if (!pud_present(*pud)) { + *address += (unsigned long)PTRS_PER_PMD * + (unsigned long)PTRS_PER_PTE * PAGE_SIZE; + return 0; + } + + if (page_to_nid(old_page) == source) { + new_page = get_new_page(old_page, private, &result); + if (!new_page) + return -ENOMEM; + + not_migrated = migrate_pud(pud, mm, *address, new_page, + old_pages); + + if (not_migrated) + __free_page(new_page); + + pages_not_migrated += not_migrated; + } + + for (i = 0; i < PTRS_PER_PUD; i++) { + int ret; + ret = migrate_page_tables_pmd(pmd_offset(pud, *address), mm, + address, source, + get_new_page, private, + old_pages); + if (ret < 0) + return ret; + pages_not_migrated += ret; + } + + return pages_not_migrated; +} + +static int migrate_page_tables_pgd(pgd_t *pgd, struct mm_struct *mm, + unsigned long *address, int source, + new_page_t get_new_page, + unsigned long private, + struct list_head *old_pages) +{ + int pages_not_migrated = 0; + int i; + int *result = NULL; + struct page *old_page = virt_to_page(pgd); + struct page *new_page; + int not_migrated; + + if (!pgd_present(*pgd)) { + *address += (unsigned long)PTRS_PER_PUD * + (unsigned long)PTRS_PER_PMD * + (unsigned long)PTRS_PER_PTE * PAGE_SIZE; + return 0; + } + + if (page_to_nid(old_page) == source) { + new_page = get_new_page(old_page, private, &result); + if (!new_page) + return -ENOMEM; + + not_migrated = migrate_pgd(pgd, mm, *address, new_page, + old_pages); + if (not_migrated) + __free_page(new_page); + + pages_not_migrated += not_migrated; + + } + for (i = 0; i < PTRS_PER_PUD; i++) { + int ret; + ret = migrate_page_tables_pud(pud_offset(pgd, *address), mm, + address, source, + get_new_page, private, + old_pages); + if (ret < 0) + return ret; + pages_not_migrated += ret; + } + return pages_not_migrated; +} + +/* similiar to migrate pages, but migrates the page tables. */ +int migrate_page_tables_mm(struct mm_struct *mm, int source, + new_page_t get_new_page, unsigned long private) +{ + int pages_not_migrated = 0; + int i; + int *result = NULL; + struct page *old_page = virt_to_page(mm->pgd); + struct page *new_page; + unsigned long address = 0UL; + int not_migrated; + LIST_HEAD(old_pages); + + if (mm->pgd == NULL) + return 0; + + for (i = 0; i < PTRS_PER_PGD && address < mm->task_size; i++) { + int ret; + ret = migrate_page_tables_pgd(pgd_offset(mm, address), mm, + &address, source, + get_new_page, private, + &old_pages); + if (ret < 0) + return ret; + + pages_not_migrated += ret; + } + + if (page_to_nid(old_page) == source) { + new_page = get_new_page(old_page, private, &result); + if (!new_page) + return -ENOMEM; + + not_migrated = migrate_top_level_page_table(mm, new_page, + &old_pages); + if (not_migrated) + __free_page(new_page); + + pages_not_migrated += not_migrated; + } + + /* reload or flush the tlbs if necessary. */ + maybe_reload_tlb_mm(mm); + + /* Add the pages freed up to the rcu list to be freed later. + * We need to do this after we flush the mm to prevent + * a possible race where the page is freed while one of + * the cpus is still looking at it. + */ + + while (!list_empty(&old_pages)) { + old_page = list_first_entry(&old_pages, struct page, lru); + list_del(&old_page->lru); + /* This is the same memory as the list + * head we are using to maintain the list. + * so we have to make sure the list_del + * comes first. + */ + INIT_RCU_HEAD(&old_page->rcu); + call_rcu(&old_page->rcu, rcu_free_pt); + } + + return pages_not_migrated; +} diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/mm/mremap.c 2.6.23a/mm/mremap.c --- 2.6.23/mm/mremap.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/mm/mremap.c 2007-10-30 06:57:49.000000000 -0700 @@ -98,6 +98,7 @@ static void move_ptes(struct vm_area_str new_ptl = pte_lockptr(mm, new_pmd); if (new_ptl != old_ptl) spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING); + delimbo_pte(&new_pte, &new_ptl, &new_pmd, mm, new_addr); arch_enter_lazy_mmu_mode(); for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE, diff -uprwNbB -X 2.6.23/Documentation/dontdiff 2.6.23/mm/rmap.c 2.6.23a/mm/rmap.c --- 2.6.23/mm/rmap.c 2007-10-09 13:31:38.000000000 -0700 +++ 2.6.23a/mm/rmap.c 2007-10-29 09:46:25.000000000 -0700 @@ -254,6 +254,7 @@ pte_t *page_check_address(struct page *p ptl = pte_lockptr(mm, pmd); spin_lock(ptl); + delimbo_pte(&pte, &ptl, &pmd, mm, address); if (pte_present(*pte) && page_to_pfn(page) == pte_pfn(*pte)) { *ptlp = ptl; return pte; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/