mm: buffered write iterator

Add an iterator data structure to operate over an iovec.  Add usercopy
operators needed by generic_file_buffered_write, and convert that function
over.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 0 insertions, 103 deletions

diff --git a/mm/filemap.h b/mm/filemap.h
deleted file mode 100644
index b500d93..0000000
--- a/mm/filemap.h
+++ /dev/null
@@ -1,103 +0,0 @@
-/*
- *	linux/mm/filemap.h
- *
- * Copyright (C) 1994-1999  Linus Torvalds
- */
-
-#ifndef __FILEMAP_H
-#define __FILEMAP_H
-
-#include <linux/types.h>
-#include <linux/fs.h>
-#include <linux/mm.h>
-#include <linux/highmem.h>
-#include <linux/uio.h>
-#include <linux/uaccess.h>
-
-size_t
-__filemap_copy_from_user_iovec_inatomic(char *vaddr,
-					const struct iovec *iov,
-					size_t base,
-					size_t bytes);
-
-/*
- * Copy as much as we can into the page and return the number of bytes which
- * were sucessfully copied.  If a fault is encountered then return the number of
- * bytes which were copied.
- */
-static inline size_t
-filemap_copy_from_user_atomic(struct page *page, unsigned long offset,
-			const struct iovec *iov, unsigned long nr_segs,
-			size_t base, size_t bytes)
-{
-	char *kaddr;
-	size_t copied;
-
-	kaddr = kmap_atomic(page, KM_USER0);
-	if (likely(nr_segs == 1)) {
-		int left;
-		char __user *buf = iov->iov_base + base;
-		left = __copy_from_user_inatomic_nocache(kaddr + offset,
-							buf, bytes);
-		copied = bytes - left;
-	} else {
-		copied = __filemap_copy_from_user_iovec_inatomic(kaddr + offset,
-							iov, base, bytes);
-	}
-	kunmap_atomic(kaddr, KM_USER0);
-
-	return copied;
-}
-
-/*
- * This has the same sideeffects and return value as
- * filemap_copy_from_user_atomic().
- * The difference is that it attempts to resolve faults.
- */
-static inline size_t
-filemap_copy_from_user(struct page *page, unsigned long offset,
-			const struct iovec *iov, unsigned long nr_segs,
-			 size_t base, size_t bytes)
-{
-	char *kaddr;
-	size_t copied;
-
-	kaddr = kmap(page);
-	if (likely(nr_segs == 1)) {
-		int left;
-		char __user *buf = iov->iov_base + base;
-		left = __copy_from_user_nocache(kaddr + offset, buf, bytes);
-		copied = bytes - left;
-	} else {
-		copied = __filemap_copy_from_user_iovec_inatomic(kaddr + offset,
-							iov, base, bytes);
-	}
-	kunmap(page);
-	return copied;
-}
-
-static inline void
-filemap_set_next_iovec(const struct iovec **iovp, unsigned long nr_segs,
-						 size_t *basep, size_t bytes)
-{
-	if (likely(nr_segs == 1)) {
-		*basep += bytes;
-	} else {
-		const struct iovec *iov = *iovp;
-		size_t base = *basep;
-
-		while (bytes) {
-			int copy = min(bytes, iov->iov_len - base);
-
-			bytes -= copy;
-			base += copy;
-			if (iov->iov_len == base) {
-				iov++;
-				base = 0;
-			}
-		}
-		*iovp = iov;
-		*basep = base;
-	}
-}
-#endif