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/*
Copyright (C) 1994,95,96,97,99,2000 Free Software Foundation, Inc.
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, or (at
your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "priv.h"
#include <string.h>
#include <fcntl.h>
#include <hurd/pager.h>
/* Actually read or write a file. The file size must already permit
the requested access. NP is the file to read/write. DATA is a buffer
to write from or fill on read. OFFSET is the absolute address (-1
not permitted here); AMT is the size of the read/write to perform;
DIR is set for writing and clear for reading. The inode must
be locked. If NOTIME is set, then don't update the mtime or atime. */
error_t
_diskfs_rdwr_internal (struct node *np,
char *data,
off_t offset,
size_t *amt,
int dir,
int notime)
{
memory_object_t memobj;
vm_prot_t prot = dir ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ;
error_t err = 0;
if (dir)
assert_backtrace (!diskfs_readonly);
if (*amt == 0)
/* Zero-length writes do not update mtime or anything else, by POSIX. */
return 0;
if (!diskfs_check_readonly () && !notime)
{
if (dir)
np->dn_set_mtime = 1;
else if (! _diskfs_noatime)
np->dn_set_atime = 1;
}
memobj = diskfs_get_filemap (np, prot);
if (memobj == MACH_PORT_NULL)
return errno;
/* pager_memcpy inherently uses vm_offset_t, which may be smaller than off_t. */
if (sizeof(off_t) > sizeof(vm_offset_t) &&
offset + *amt > ((off_t) 1) << (sizeof(vm_offset_t) * 8))
err = EFBIG;
else
err = pager_memcpy (diskfs_get_filemap_pager_struct (np), memobj,
offset, data, amt, prot);
if (!diskfs_check_readonly () && !notime)
{
if (dir)
np->dn_set_mtime = 1;
else if (!_diskfs_noatime)
np->dn_set_atime = 1;
}
mach_port_deallocate (mach_task_self (), memobj);
return err;
}
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