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/*
Copyright (C) 1994 Free Software Foundation
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"
/* Reading and writing of files. this is called by other filesystem
routines and handles extension of files and reads of more than is
left automatically. NP is the node to be read or written. DATA
will be written or filled. OFF identifies where in thi fel the I/O
is to take place (-1 is not allowed). AMT is the size of DATA and
tells how much to copy. DIR is 1 for writing and 0 for reading.
CRED is the user doing the access (only used to validate attempted
file extension). */
error_t
diskfs_noderdwr (struct inode *ip,
char *data,
off_t off,
int amt,
int dir,
struct protid *cred)
{
error_t err;
if (err = ioserver_get_conch (&ip->i_conch))
return err;
if (!(err = catch_exception ()))
{
if (dir)
while (off + amt > ip->i_allocsize)
if (err = file_extend (ip, off + amt, cred))
return err;
if (off + amt > ip->di->di_size)
{
assert (dir); /* reads can't go past EOF internally */
if (dir)
{
ip->di->di_size = off + amt;
ip->di->di_ctime = wallclock->seconds;
}
}
end_catch_exception ();
}
if (err)
return err;
err = io_rdwr (ip, data, off, amt, dir);
return err;
}
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