From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f42.google.com (mail-pa0-f42.google.com [209.85.220.42]) by kanga.kvack.org (Postfix) with ESMTP id 855A26B003A for ; Mon, 23 Sep 2013 08:06:15 -0400 (EDT) Received: by mail-pa0-f42.google.com with SMTP id lj1so3514616pab.29 for ; Mon, 23 Sep 2013 05:06:15 -0700 (PDT) From: "Kirill A. Shutemov" Subject: [PATCHv6 15/22] thp, mm: naive support of thp in generic_perform_write Date: Mon, 23 Sep 2013 15:05:43 +0300 Message-Id: <1379937950-8411-16-git-send-email-kirill.shutemov@linux.intel.com> In-Reply-To: <1379937950-8411-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1379937950-8411-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrea Arcangeli , Andrew Morton Cc: Al Viro , Hugh Dickins , Wu Fengguang , Jan Kara , Mel Gorman , linux-mm@kvack.org, Andi Kleen , Matthew Wilcox , "Kirill A. Shutemov" , Hillf Danton , Dave Hansen , Ning Qu , Alexander Shishkin , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" For now we still write/read at most PAGE_CACHE_SIZE bytes a time. This implementation doesn't cover address spaces with backing storage. Signed-off-by: Kirill A. Shutemov --- mm/filemap.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/mm/filemap.c b/mm/filemap.c index 410879a801..38d6856737 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2384,12 +2384,14 @@ static ssize_t generic_perform_write(struct file *file, if (segment_eq(get_fs(), KERNEL_DS)) flags |= AOP_FLAG_UNINTERRUPTIBLE; + i_split_down_read(mapping->host); do { struct page *page; unsigned long offset; /* Offset into pagecache page */ unsigned long bytes; /* Bytes to write to page */ size_t copied; /* Bytes copied from user */ void *fsdata; + int subpage_nr = 0; offset = (pos & (PAGE_CACHE_SIZE - 1)); bytes = min_t(unsigned long, PAGE_CACHE_SIZE - offset, @@ -2419,8 +2421,14 @@ again: if (mapping_writably_mapped(mapping)) flush_dcache_page(page); + if (PageTransHuge(page)) { + off_t huge_offset = pos & ~HPAGE_PMD_MASK; + subpage_nr = huge_offset >> PAGE_CACHE_SHIFT; + } + pagefault_disable(); - copied = iov_iter_copy_from_user_atomic(page, i, offset, bytes); + copied = iov_iter_copy_from_user_atomic(page + subpage_nr, i, + offset, bytes); pagefault_enable(); flush_dcache_page(page); @@ -2457,6 +2465,7 @@ again: } } while (iov_iter_count(i)); + i_split_up_read(mapping->host); return written ? written : status; } -- 1.8.4.rc3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org