[CIFS] use simple_prepare_write to zero page data (8803863a) · Commits · 戴 / test

It's common for file systems to need to zero data on either side of a write, if a page is not Uptodate during prepare_write. It just so happens that simple_prepare_write() in libfs.c does exactly that, so we can avoid duplication and just call that function to zero page data. Signed-off-by:

Nate Diller <nate.diller@gmail.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Steve French <sfrench@us.ibm.com>

fs/cifs/file.c

+1 −8

Original line number	Diff line number	Diff line
		@@ -1966,14 +1966,7 @@ static int cifs_prepare_write(struct file file, struct page page,
		* We don't need to read data beyond the end of the file.
		* zero it, and set the page uptodate
		*/
		void *kaddr = kmap_atomic(page, KM_USER0);

		if (from)
		memset(kaddr, 0, from);
		if (to < PAGE_CACHE_SIZE)
		memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
		flush_dcache_page(page);
		kunmap_atomic(kaddr, KM_USER0);
		simple_prepare_write(file, page, from, to);
		SetPageUptodate(page);
		} else if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
		/* might as well read a page, it is fast enough */

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