kernel-ark/net/core/iovec.c
Tim Schmielau cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00

239 lines
5.1 KiB
C

/*
* iovec manipulation routines.
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Fixes:
* Andrew Lunn : Errors in iovec copying.
* Pedro Roque : Added memcpy_fromiovecend and
* csum_..._fromiovecend.
* Andi Kleen : fixed error handling for 2.1
* Alexey Kuznetsov: 2.1 optimisations
* Andi Kleen : Fix csum*fromiovecend for IPv6.
*/
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
#include <net/checksum.h>
#include <net/sock.h>
/*
* Verify iovec. The caller must ensure that the iovec is big enough
* to hold the message iovec.
*
* Save time not doing access_ok. copy_*_user will make this work
* in any case.
*/
int verify_iovec(struct msghdr *m, struct iovec *iov, char *address, int mode)
{
int size, err, ct;
if (m->msg_namelen) {
if (mode == VERIFY_READ) {
err = move_addr_to_kernel(m->msg_name, m->msg_namelen,
address);
if (err < 0)
return err;
}
m->msg_name = address;
} else {
m->msg_name = NULL;
}
size = m->msg_iovlen * sizeof(struct iovec);
if (copy_from_user(iov, m->msg_iov, size))
return -EFAULT;
m->msg_iov = iov;
err = 0;
for (ct = 0; ct < m->msg_iovlen; ct++) {
err += iov[ct].iov_len;
/*
* Goal is not to verify user data, but to prevent returning
* negative value, which is interpreted as errno.
* Overflow is still possible, but it is harmless.
*/
if (err < 0)
return -EMSGSIZE;
}
return err;
}
/*
* Copy kernel to iovec. Returns -EFAULT on error.
*
* Note: this modifies the original iovec.
*/
int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len)
{
while (len > 0) {
if (iov->iov_len) {
int copy = min_t(unsigned int, iov->iov_len, len);
if (copy_to_user(iov->iov_base, kdata, copy))
return -EFAULT;
kdata += copy;
len -= copy;
iov->iov_len -= copy;
iov->iov_base += copy;
}
iov++;
}
return 0;
}
/*
* Copy iovec to kernel. Returns -EFAULT on error.
*
* Note: this modifies the original iovec.
*/
int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len)
{
while (len > 0) {
if (iov->iov_len) {
int copy = min_t(unsigned int, len, iov->iov_len);
if (copy_from_user(kdata, iov->iov_base, copy))
return -EFAULT;
len -= copy;
kdata += copy;
iov->iov_base += copy;
iov->iov_len -= copy;
}
iov++;
}
return 0;
}
/*
* For use with ip_build_xmit
*/
int memcpy_fromiovecend(unsigned char *kdata, struct iovec *iov, int offset,
int len)
{
/* Skip over the finished iovecs */
while (offset >= iov->iov_len) {
offset -= iov->iov_len;
iov++;
}
while (len > 0) {
u8 __user *base = iov->iov_base + offset;
int copy = min_t(unsigned int, len, iov->iov_len - offset);
offset = 0;
if (copy_from_user(kdata, base, copy))
return -EFAULT;
len -= copy;
kdata += copy;
iov++;
}
return 0;
}
/*
* And now for the all-in-one: copy and checksum from a user iovec
* directly to a datagram
* Calls to csum_partial but the last must be in 32 bit chunks
*
* ip_build_xmit must ensure that when fragmenting only the last
* call to this function will be unaligned also.
*/
int csum_partial_copy_fromiovecend(unsigned char *kdata, struct iovec *iov,
int offset, unsigned int len, __wsum *csump)
{
__wsum csum = *csump;
int partial_cnt = 0, err = 0;
/* Skip over the finished iovecs */
while (offset >= iov->iov_len) {
offset -= iov->iov_len;
iov++;
}
while (len > 0) {
u8 __user *base = iov->iov_base + offset;
int copy = min_t(unsigned int, len, iov->iov_len - offset);
offset = 0;
/* There is a remnant from previous iov. */
if (partial_cnt) {
int par_len = 4 - partial_cnt;
/* iov component is too short ... */
if (par_len > copy) {
if (copy_from_user(kdata, base, copy))
goto out_fault;
kdata += copy;
base += copy;
partial_cnt += copy;
len -= copy;
iov++;
if (len)
continue;
*csump = csum_partial(kdata - partial_cnt,
partial_cnt, csum);
goto out;
}
if (copy_from_user(kdata, base, par_len))
goto out_fault;
csum = csum_partial(kdata - partial_cnt, 4, csum);
kdata += par_len;
base += par_len;
copy -= par_len;
len -= par_len;
partial_cnt = 0;
}
if (len > copy) {
partial_cnt = copy % 4;
if (partial_cnt) {
copy -= partial_cnt;
if (copy_from_user(kdata + copy, base + copy,
partial_cnt))
goto out_fault;
}
}
if (copy) {
csum = csum_and_copy_from_user(base, kdata, copy,
csum, &err);
if (err)
goto out;
}
len -= copy + partial_cnt;
kdata += copy + partial_cnt;
iov++;
}
*csump = csum;
out:
return err;
out_fault:
err = -EFAULT;
goto out;
}
EXPORT_SYMBOL(csum_partial_copy_fromiovecend);
EXPORT_SYMBOL(memcpy_fromiovec);
EXPORT_SYMBOL(memcpy_fromiovecend);
EXPORT_SYMBOL(memcpy_toiovec);