From 01f2705daf5a36208e69d7cf95db9c330f843af6 Mon Sep 17 00:00:00 2001 From: Nate Diller Date: Wed, 9 May 2007 02:35:07 -0700 Subject: fs: convert core functions to zero_user_page It's very common for file systems to need to zero part or all of a page, the simplist way is just to use kmap_atomic() and memset(). There's actually a library function in include/linux/highmem.h that does exactly that, but it's confusingly named memclear_highpage_flush(), which is descriptive of *how* it does the work rather than what the *purpose* is. So this patchset renames the function to zero_user_page(), and calls it from the various places that currently open code it. This first patch introduces the new function call, and converts all the core kernel callsites, both the open-coded ones and the old memclear_highpage_flush() ones. Following this patch is a series of conversions for each file system individually, per AKPM, and finally a patch deprecating the old call. The diffstat below shows the entire patchset. [akpm@linux-foundation.org: fix a few things] Signed-off-by: Nate Diller Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/mpage.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) (limited to 'fs/mpage.c') diff --git a/fs/mpage.c b/fs/mpage.c index fa2441f57b41..0fb914fc2ee0 100644 --- a/fs/mpage.c +++ b/fs/mpage.c @@ -284,11 +284,9 @@ do_mpage_readpage(struct bio *bio, struct page *page, unsigned nr_pages, } if (first_hole != blocks_per_page) { - char *kaddr = kmap_atomic(page, KM_USER0); - memset(kaddr + (first_hole << blkbits), 0, - PAGE_CACHE_SIZE - (first_hole << blkbits)); - flush_dcache_page(page); - kunmap_atomic(kaddr, KM_USER0); + zero_user_page(page, first_hole << blkbits, + PAGE_CACHE_SIZE - (first_hole << blkbits), + KM_USER0); if (first_hole == 0) { SetPageUptodate(page); unlock_page(page); @@ -576,14 +574,11 @@ page_is_mapped: * written out to the file." */ unsigned offset = i_size & (PAGE_CACHE_SIZE - 1); - char *kaddr; if (page->index > end_index || !offset) goto confused; - kaddr = kmap_atomic(page, KM_USER0); - memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset); - flush_dcache_page(page); - kunmap_atomic(kaddr, KM_USER0); + zero_user_page(page, offset, PAGE_CACHE_SIZE - offset, + KM_USER0); } /* -- cgit v1.2.3