X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=mm%2Frmap.c;h=59da5b734c801c6186621fa5dabf94108268fd51;hb=3ebad5905609476a4ff1151a66b21d9794009961;hp=e2155d791d9967a6e1bbf496ee9b8728dd9bb4c5;hpb=ccaa36f73544163ef6e15eb29a620130755f6001;p=powerpc.git diff --git a/mm/rmap.c b/mm/rmap.c index e2155d791d..59da5b734c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -21,27 +21,21 @@ * Lock ordering in mm: * * inode->i_mutex (while writing or truncating, not reading or faulting) - * inode->i_alloc_sem - * - * When a page fault occurs in writing from user to file, down_read - * of mmap_sem nests within i_mutex; in sys_msync, i_mutex nests within - * down_read of mmap_sem; i_mutex and down_write of mmap_sem are never - * taken together; in truncation, i_mutex is taken outermost. - * - * mm->mmap_sem - * page->flags PG_locked (lock_page) - * mapping->i_mmap_lock - * anon_vma->lock - * mm->page_table_lock or pte_lock - * zone->lru_lock (in mark_page_accessed, isolate_lru_page) - * swap_lock (in swap_duplicate, swap_info_get) - * mmlist_lock (in mmput, drain_mmlist and others) - * mapping->private_lock (in __set_page_dirty_buffers) - * inode_lock (in set_page_dirty's __mark_inode_dirty) - * sb_lock (within inode_lock in fs/fs-writeback.c) - * mapping->tree_lock (widely used, in set_page_dirty, - * in arch-dependent flush_dcache_mmap_lock, - * within inode_lock in __sync_single_inode) + * inode->i_alloc_sem (vmtruncate_range) + * mm->mmap_sem + * page->flags PG_locked (lock_page) + * mapping->i_mmap_lock + * anon_vma->lock + * mm->page_table_lock or pte_lock + * zone->lru_lock (in mark_page_accessed, isolate_lru_page) + * swap_lock (in swap_duplicate, swap_info_get) + * mmlist_lock (in mmput, drain_mmlist and others) + * mapping->private_lock (in __set_page_dirty_buffers) + * inode_lock (in set_page_dirty's __mark_inode_dirty) + * sb_lock (within inode_lock in fs/fs-writeback.c) + * mapping->tree_lock (widely used, in set_page_dirty, + * in arch-dependent flush_dcache_mmap_lock, + * within inode_lock in __sync_single_inode) */ #include @@ -53,6 +47,7 @@ #include #include #include +#include #include @@ -188,7 +183,7 @@ void __init anon_vma_init(void) */ static struct anon_vma *page_lock_anon_vma(struct page *page) { - struct anon_vma *anon_vma = NULL; + struct anon_vma *anon_vma; unsigned long anon_mapping; rcu_read_lock(); @@ -200,9 +195,16 @@ static struct anon_vma *page_lock_anon_vma(struct page *page) anon_vma = (struct anon_vma *) (anon_mapping - PAGE_MAPPING_ANON); spin_lock(&anon_vma->lock); + return anon_vma; out: rcu_read_unlock(); - return anon_vma; + return NULL; +} + +static void page_unlock_anon_vma(struct anon_vma *anon_vma) +{ + spin_unlock(&anon_vma->lock); + rcu_read_unlock(); } /* @@ -338,7 +340,8 @@ static int page_referenced_anon(struct page *page) if (!mapcount) break; } - spin_unlock(&anon_vma->lock); + + page_unlock_anon_vma(anon_vma); return referenced; } @@ -438,7 +441,7 @@ static int page_mkclean_one(struct page *page, struct vm_area_struct *vma) { struct mm_struct *mm = vma->vm_mm; unsigned long address; - pte_t *pte, entry; + pte_t *pte; spinlock_t *ptl; int ret = 0; @@ -450,17 +453,18 @@ static int page_mkclean_one(struct page *page, struct vm_area_struct *vma) if (!pte) goto out; - if (!pte_dirty(*pte) && !pte_write(*pte)) - goto unlock; + if (pte_dirty(*pte) || pte_write(*pte)) { + pte_t entry; - entry = ptep_get_and_clear(mm, address, pte); - entry = pte_mkclean(entry); - entry = pte_wrprotect(entry); - ptep_establish(vma, address, pte, entry); - lazy_mmu_prot_update(entry); - ret = 1; + flush_cache_page(vma, address, pte_pfn(*pte)); + entry = ptep_clear_flush(vma, address, pte); + entry = pte_wrprotect(entry); + entry = pte_mkclean(entry); + set_pte_at(mm, address, pte, entry); + lazy_mmu_prot_update(entry); + ret = 1; + } -unlock: pte_unmap_unlock(pte, ptl); out: return ret; @@ -494,6 +498,10 @@ int page_mkclean(struct page *page) struct address_space *mapping = page_mapping(page); if (mapping) ret = page_mkclean_file(mapping, page); + if (page_test_dirty(page)) { + page_clear_dirty(page); + ret = 1; + } } return ret; @@ -573,18 +581,23 @@ void page_add_file_rmap(struct page *page) * * The caller needs to hold the pte lock. */ -void page_remove_rmap(struct page *page) +void page_remove_rmap(struct page *page, struct vm_area_struct *vma) { if (atomic_add_negative(-1, &page->_mapcount)) { -#ifdef CONFIG_DEBUG_VM if (unlikely(page_mapcount(page) < 0)) { printk (KERN_EMERG "Eeek! page_mapcount(page) went negative! (%d)\n", page_mapcount(page)); + printk (KERN_EMERG " page pfn = %lx\n", page_to_pfn(page)); printk (KERN_EMERG " page->flags = %lx\n", page->flags); printk (KERN_EMERG " page->count = %x\n", page_count(page)); printk (KERN_EMERG " page->mapping = %p\n", page->mapping); + print_symbol (KERN_EMERG " vma->vm_ops = %s\n", (unsigned long)vma->vm_ops); + if (vma->vm_ops) + print_symbol (KERN_EMERG " vma->vm_ops->nopage = %s\n", (unsigned long)vma->vm_ops->nopage); + if (vma->vm_file && vma->vm_file->f_op) + print_symbol (KERN_EMERG " vma->vm_file->f_op->mmap = %s\n", (unsigned long)vma->vm_file->f_op->mmap); + BUG(); } -#endif - BUG_ON(page_mapcount(page) < 0); + /* * It would be tidy to reset the PageAnon mapping here, * but that might overwrite a racing page_add_anon_rmap @@ -594,8 +607,10 @@ void page_remove_rmap(struct page *page) * Leaving it set also helps swapoff to reinstate ptes * faster for those pages still in swapcache. */ - if (page_test_and_clear_dirty(page)) + if (page_test_dirty(page)) { + page_clear_dirty(page); set_page_dirty(page); + } __dec_zone_page_state(page, PageAnon(page) ? NR_ANON_PAGES : NR_FILE_MAPPED); } @@ -686,7 +701,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, dec_mm_counter(mm, file_rss); - page_remove_rmap(page); + page_remove_rmap(page, vma); page_cache_release(page); out_unmap: @@ -776,7 +791,7 @@ static void try_to_unmap_cluster(unsigned long cursor, if (pte_dirty(pteval)) set_page_dirty(page); - page_remove_rmap(page); + page_remove_rmap(page, vma); page_cache_release(page); dec_mm_counter(mm, file_rss); (*mapcount)--; @@ -799,7 +814,8 @@ static int try_to_unmap_anon(struct page *page, int migration) if (ret == SWAP_FAIL || !page_mapped(page)) break; } - spin_unlock(&anon_vma->lock); + + page_unlock_anon_vma(anon_vma); return ret; }