diff options
| -rw-r--r-- | mm/mempolicy.c | 270 |
1 files changed, 138 insertions, 132 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 4b077ec6c00..7051fe450e9 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -183,55 +183,9 @@ static struct mempolicy *mpol_new(int mode, nodemask_t *nodes) return policy; } -/* Check if we are the only process mapping the page in question */ -static inline int single_mm_mapping(struct mm_struct *mm, - struct address_space *mapping) -{ - struct vm_area_struct *vma; - struct prio_tree_iter iter; - int rc = 1; - - spin_lock(&mapping->i_mmap_lock); - vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, 0, ULONG_MAX) - if (mm != vma->vm_mm) { - rc = 0; - goto out; - } - list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) - if (mm != vma->vm_mm) { - rc = 0; - goto out; - } -out: - spin_unlock(&mapping->i_mmap_lock); - return rc; -} - -/* - * Add a page to be migrated to the pagelist - */ -static void migrate_page_add(struct vm_area_struct *vma, - struct page *page, struct list_head *pagelist, unsigned long flags) -{ - /* - * Avoid migrating a page that is shared by others and not writable. - */ - if ((flags & MPOL_MF_MOVE_ALL) || !page->mapping || PageAnon(page) || - mapping_writably_mapped(page->mapping) || - single_mm_mapping(vma->vm_mm, page->mapping)) { - int rc = isolate_lru_page(page); - - if (rc == 1) - list_add(&page->lru, pagelist); - /* - * If the isolate attempt was not successful then we just - * encountered an unswappable page. Something must be wrong. - */ - WARN_ON(rc == 0); - } -} - static void gather_stats(struct page *, void *); +static void migrate_page_add(struct vm_area_struct *vma, + struct page *page, struct list_head *pagelist, unsigned long flags); /* Scan through pages checking if pages follow certain conditions. */ static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd, @@ -440,90 +394,6 @@ static int contextualize_policy(int mode, nodemask_t *nodes) return mpol_check_policy(mode, nodes); } -static int swap_pages(struct list_head *pagelist) -{ - LIST_HEAD(moved); - LIST_HEAD(failed); - int n; - - n = migrate_pages(pagelist, NULL, &moved, &failed); - putback_lru_pages(&failed); - putback_lru_pages(&moved); - - return n; -} - -long do_mbind(unsigned long start, unsigned long len, - unsigned long mode, nodemask_t *nmask, unsigned long flags) -{ - struct vm_area_struct *vma; - struct mm_struct *mm = current->mm; - struct mempolicy *new; - unsigned long end; - int err; - LIST_HEAD(pagelist); - - if ((flags & ~(unsigned long)(MPOL_MF_STRICT | - MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) - || mode > MPOL_MAX) - return -EINVAL; - if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_RESOURCE)) - return -EPERM; - - if (start & ~PAGE_MASK) - return -EINVAL; - - if (mode == MPOL_DEFAULT) - flags &= ~MPOL_MF_STRICT; - - len = (len + PAGE_SIZE - 1) & PAGE_MASK; - end = start + len; - - if (end < start) - return -EINVAL; - if (end == start) - return 0; - - if (mpol_check_policy(mode, nmask)) - return -EINVAL; - - new = mpol_new(mode, nmask); - if (IS_ERR(new)) - return PTR_ERR(new); - - /* - * If we are using the default policy then operation - * on discontinuous address spaces is okay after all - */ - if (!new) - flags |= MPOL_MF_DISCONTIG_OK; - - PDprintk("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len, - mode,nodes_addr(nodes)[0]); - - down_write(&mm->mmap_sem); - vma = check_range(mm, start, end, nmask, - flags | MPOL_MF_INVERT, &pagelist); - - err = PTR_ERR(vma); - if (!IS_ERR(vma)) { - int nr_failed = 0; - - err = mbind_range(vma, start, end, new); - if (!list_empty(&pagelist)) - nr_failed = swap_pages(&pagelist); - - if (!err && nr_failed && (flags & MPOL_MF_STRICT)) - err = -EIO; - } - if (!list_empty(&pagelist)) - putback_lru_pages(&pagelist); - - up_write(&mm->mmap_sem); - mpol_free(new); - return err; -} - /* Set the process memory policy */ long do_set_mempolicy(int mode, nodemask_t *nodes) { @@ -644,6 +514,71 @@ long do_get_mempolicy(int *policy, nodemask_t *nmask, } /* + * page migration + */ + +/* Check if we are the only process mapping the page in question */ +static inline int single_mm_mapping(struct mm_struct *mm, + struct address_space *mapping) +{ + struct vm_area_struct *vma; + struct prio_tree_iter iter; + int rc = 1; + + spin_lock(&mapping->i_mmap_lock); + vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, 0, ULONG_MAX) + if (mm != vma->vm_mm) { + rc = 0; + goto out; + } + list_for_each_entry(vma, &mapping->i_mmap_nonlinear, shared.vm_set.list) + if (mm != vma->vm_mm) { + rc = 0; + goto out; + } +out: + spin_unlock(&mapping->i_mmap_lock); + return rc; +} + +/* + * Add a page to be migrated to the pagelist + */ +static void migrate_page_add(struct vm_area_struct *vma, + struct page *page, struct list_head *pagelist, unsigned long flags) +{ + /* + * Avoid migrating a page that is shared by others and not writable. + */ + if ((flags & MPOL_MF_MOVE_ALL) || !page->mapping || PageAnon(page) || + mapping_writably_mapped(page->mapping) || + single_mm_mapping(vma->vm_mm, page->mapping)) { + int rc = isolate_lru_page(page); + + if (rc == 1) + list_add(&page->lru, pagelist); + /* + * If the isolate attempt was not successful then we just + * encountered an unswappable page. Something must be wrong. + */ + WARN_ON(rc == 0); + } +} + +static int swap_pages(struct list_head *pagelist) +{ + LIST_HEAD(moved); + LIST_HEAD(failed); + int n; + + n = migrate_pages(pagelist, NULL, &moved, &failed); + putback_lru_pages(&failed); + putback_lru_pages(&moved); + + return n; +} + +/* * For now migrate_pages simply swaps out the pages from nodes that are in * the source set but not in the target set. In the future, we would * want a function that moves pages between the two nodesets in such @@ -673,6 +608,77 @@ int do_migrate_pages(struct mm_struct *mm, return count; } +long do_mbind(unsigned long start, unsigned long len, + unsigned long mode, nodemask_t *nmask, unsigned long flags) +{ + struct vm_area_struct *vma; + struct mm_struct *mm = current->mm; + struct mempolicy *new; + unsigned long end; + int err; + LIST_HEAD(pagelist); + + if ((flags & ~(unsigned long)(MPOL_MF_STRICT | + MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) + || mode > MPOL_MAX) + return -EINVAL; + if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_RESOURCE)) + return -EPERM; + + if (start & ~PAGE_MASK) + return -EINVAL; + + if (mode == MPOL_DEFAULT) + flags &= ~MPOL_MF_STRICT; + + len = (len + PAGE_SIZE - 1) & PAGE_MASK; + end = start + len; + + if (end < start) + return -EINVAL; + if (end == start) + return 0; + + if (mpol_check_policy(mode, nmask)) + return -EINVAL; + + new = mpol_new(mode, nmask); + if (IS_ERR(new)) + return PTR_ERR(new); + + /* + * If we are using the default policy then operation + * on discontinuous address spaces is okay after all + */ + if (!new) + flags |= MPOL_MF_DISCONTIG_OK; + + PDprintk("mbind %lx-%lx mode:%ld nodes:%lx\n",start,start+len, + mode,nodes_addr(nodes)[0]); + + down_write(&mm->mmap_sem); + vma = check_range(mm, start, end, nmask, + flags | MPOL_MF_INVERT, &pagelist); + + err = PTR_ERR(vma); + if (!IS_ERR(vma)) { + int nr_failed = 0; + + err = mbind_range(vma, start, end, new); + if (!list_empty(&pagelist)) + nr_failed = swap_pages(&pagelist); + + if (!err && nr_failed && (flags & MPOL_MF_STRICT)) + err = -EIO; + } + if (!list_empty(&pagelist)) + putback_lru_pages(&pagelist); + + up_write(&mm->mmap_sem); + mpol_free(new); + return err; +} + /* * User space interface with variable sized bitmaps for nodelists. */ |