4 * Copyright (C) 1994-1999 Linus Torvalds
10 #include <linux/types.h>
13 #include <linux/highmem.h>
14 #include <linux/uio.h>
15 #include <linux/uaccess.h>
18 __filemap_copy_from_user_iovec_inatomic(char *vaddr,
19 const struct iovec *iov,
24 * Copy as much as we can into the page and return the number of bytes which
25 * were sucessfully copied. If a fault is encountered then return the number of
26 * bytes which were copied.
29 filemap_copy_from_user_atomic(struct page *page, unsigned long offset,
30 const struct iovec *iov, unsigned long nr_segs,
31 size_t base, size_t bytes)
36 kaddr = kmap_atomic(page, KM_USER0);
37 if (likely(nr_segs == 1)) {
39 char __user *buf = iov->iov_base + base;
40 left = __copy_from_user_inatomic_nocache(kaddr + offset,
42 copied = bytes - left;
44 copied = __filemap_copy_from_user_iovec_inatomic(kaddr + offset,
47 kunmap_atomic(kaddr, KM_USER0);
53 * This has the same sideeffects and return value as
54 * filemap_copy_from_user_atomic().
55 * The difference is that it attempts to resolve faults.
58 filemap_copy_from_user(struct page *page, unsigned long offset,
59 const struct iovec *iov, unsigned long nr_segs,
60 size_t base, size_t bytes)
66 if (likely(nr_segs == 1)) {
68 char __user *buf = iov->iov_base + base;
69 left = __copy_from_user_nocache(kaddr + offset, buf, bytes);
70 copied = bytes - left;
72 copied = __filemap_copy_from_user_iovec_inatomic(kaddr + offset,
80 filemap_set_next_iovec(const struct iovec **iovp, unsigned long nr_segs,
81 size_t *basep, size_t bytes)
83 if (likely(nr_segs == 1)) {
86 const struct iovec *iov = *iovp;
90 int copy = min(bytes, iov->iov_len - base);
94 if (iov->iov_len == base) {