ceffc07852
- generic_file* file operations do no longer have a xip/non-xip split - filemap_xip.c implements a new set of fops that require get_xip_page aop to work proper. all new fops are exported GPL-only (don't like to see whatever code use those except GPL modules) - __xip_unmap now uses page_check_address, which is no longer static in rmap.c, and defined in linux/rmap.h - mm/filemap.h is now much more clean, plainly having just Linus' inline funcs moved here from filemap.c - fix includes in filemap_xip to make it build cleanly on i386 Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
94 lines
2.2 KiB
C
94 lines
2.2 KiB
C
/*
|
|
* 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/config.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
extern size_t
|
|
__filemap_copy_from_user_iovec(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 clear the page
|
|
* out to (offset+bytes) and return the number of bytes which were copied.
|
|
*/
|
|
static inline size_t
|
|
filemap_copy_from_user(struct page *page, unsigned long offset,
|
|
const char __user *buf, unsigned bytes)
|
|
{
|
|
char *kaddr;
|
|
int left;
|
|
|
|
kaddr = kmap_atomic(page, KM_USER0);
|
|
left = __copy_from_user_inatomic(kaddr + offset, buf, bytes);
|
|
kunmap_atomic(kaddr, KM_USER0);
|
|
|
|
if (left != 0) {
|
|
/* Do it the slow way */
|
|
kaddr = kmap(page);
|
|
left = __copy_from_user(kaddr + offset, buf, bytes);
|
|
kunmap(page);
|
|
}
|
|
return bytes - left;
|
|
}
|
|
|
|
/*
|
|
* This has the same sideeffects and return value as filemap_copy_from_user().
|
|
* The difference is that on a fault we need to memset the remainder of the
|
|
* page (out to offset+bytes), to emulate filemap_copy_from_user()'s
|
|
* single-segment behaviour.
|
|
*/
|
|
static inline size_t
|
|
filemap_copy_from_user_iovec(struct page *page, unsigned long offset,
|
|
const struct iovec *iov, size_t base, size_t bytes)
|
|
{
|
|
char *kaddr;
|
|
size_t copied;
|
|
|
|
kaddr = kmap_atomic(page, KM_USER0);
|
|
copied = __filemap_copy_from_user_iovec(kaddr + offset, iov,
|
|
base, bytes);
|
|
kunmap_atomic(kaddr, KM_USER0);
|
|
if (copied != bytes) {
|
|
kaddr = kmap(page);
|
|
copied = __filemap_copy_from_user_iovec(kaddr + offset, iov,
|
|
base, bytes);
|
|
kunmap(page);
|
|
}
|
|
return copied;
|
|
}
|
|
|
|
static inline void
|
|
filemap_set_next_iovec(const struct iovec **iovp, size_t *basep, size_t bytes)
|
|
{
|
|
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
|