X-Git-Url: http://git.cascardo.info/?p=cascardo%2Flinux.git;a=blobdiff_plain;f=mm%2Ffilemap.c;h=849f459ad0780e27bc256ff13fd52fa8c9007661;hp=2d0986a64f1f729548937e239860ac7620a16393;hb=fed41f7d039bad02f94cad9059e4b14cd81d13f2;hpb=f785fb2ec0cbe73165333ea1f23cce36c7fc2521 diff --git a/mm/filemap.c b/mm/filemap.c index 2d0986a64f1f..849f459ad078 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -169,33 +169,35 @@ static int page_cache_tree_insert(struct address_space *mapping, static void page_cache_tree_delete(struct address_space *mapping, struct page *page, void *shadow) { - struct radix_tree_node *node; int i, nr = PageHuge(page) ? 1 : hpage_nr_pages(page); VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_PAGE(PageTail(page), page); VM_BUG_ON_PAGE(nr != 1 && shadow, page); - if (shadow) { - mapping->nrexceptional += nr; - /* - * Make sure the nrexceptional update is committed before - * the nrpages update so that final truncate racing - * with reclaim does not see both counters 0 at the - * same time and miss a shadow entry. - */ - smp_wmb(); - } - mapping->nrpages -= nr; - for (i = 0; i < nr; i++) { - node = radix_tree_replace_clear_tags(&mapping->page_tree, - page->index + i, shadow); + struct radix_tree_node *node; + void **slot; + + __radix_tree_lookup(&mapping->page_tree, page->index + i, + &node, &slot); + + radix_tree_clear_tags(&mapping->page_tree, node, slot); + if (!node) { VM_BUG_ON_PAGE(nr != 1, page); - return; + /* + * We need a node to properly account shadow + * entries. Don't plant any without. XXX + */ + shadow = NULL; } + radix_tree_replace_slot(slot, shadow); + + if (!node) + break; + workingset_node_pages_dec(node); if (shadow) workingset_node_shadows_inc(node); @@ -219,6 +221,18 @@ static void page_cache_tree_delete(struct address_space *mapping, &node->private_list); } } + + if (shadow) { + mapping->nrexceptional += nr; + /* + * Make sure the nrexceptional update is committed before + * the nrpages update so that final truncate racing + * with reclaim does not see both counters 0 at the + * same time and miss a shadow entry. + */ + smp_wmb(); + } + mapping->nrpages -= nr; } /* @@ -619,7 +633,6 @@ int replace_page_cache_page(struct page *old, struct page *new, gfp_t gfp_mask) __delete_from_page_cache(old, NULL); error = page_cache_tree_insert(mapping, new, NULL); BUG_ON(error); - mapping->nrpages++; /* * hugetlb pages do not participate in page cache accounting. @@ -1674,6 +1687,10 @@ static ssize_t do_generic_file_read(struct file *filp, loff_t *ppos, unsigned int prev_offset; int error = 0; + if (unlikely(*ppos >= inode->i_sb->s_maxbytes)) + return -EINVAL; + iov_iter_truncate(iter, inode->i_sb->s_maxbytes); + index = *ppos >> PAGE_SHIFT; prev_index = ra->prev_pos >> PAGE_SHIFT; prev_offset = ra->prev_pos & (PAGE_SIZE-1); @@ -1708,7 +1725,9 @@ find_page: * wait_on_page_locked is used to avoid unnecessarily * serialisations and why it's safe. */ - wait_on_page_locked_killable(page); + error = wait_on_page_locked_killable(page); + if (unlikely(error)) + goto readpage_error; if (PageUptodate(page)) goto page_ok; @@ -1910,17 +1929,19 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) if (iocb->ki_flags & IOCB_DIRECT) { struct address_space *mapping = file->f_mapping; struct inode *inode = mapping->host; + struct iov_iter data = *iter; loff_t size; size = i_size_read(inode); retval = filemap_write_and_wait_range(mapping, iocb->ki_pos, iocb->ki_pos + count - 1); - if (!retval) { - struct iov_iter data = *iter; - retval = mapping->a_ops->direct_IO(iocb, &data); - } + if (retval < 0) + goto out; - if (retval > 0) { + file_accessed(file); + + retval = mapping->a_ops->direct_IO(iocb, &data); + if (retval >= 0) { iocb->ki_pos += retval; iov_iter_advance(iter, retval); } @@ -1935,10 +1956,8 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter) * DAX files, so don't bother trying. */ if (retval < 0 || !iov_iter_count(iter) || iocb->ki_pos >= size || - IS_DAX(inode)) { - file_accessed(file); + IS_DAX(inode)) goto out; - } } retval = do_generic_file_read(file, &iocb->ki_pos, iter, retval);