97cbd5e722
Summary: Open file list is currently created as statically allocated array (64 items). Once this array is filled up, loader will not be able to operate with files. In most cases, this mechanism is good enough, but the problem appears, when we have many disks with zfs pool(s). In current loader implementation, all discovered zfs pool configurations are kept in memory and disk devices open - consuming the open file array. Rewrite the open file mechanism to use dynamically allocated list. Reviewed by: imp MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D31364
144 lines
4.5 KiB
C
144 lines
4.5 KiB
C
/* $NetBSD: lseek.c,v 1.4 1997/01/22 00:38:10 cgd Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* The Mach Operating System project at Carnegie-Mellon University.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* @(#)lseek.c 8.1 (Berkeley) 6/11/93
|
|
*
|
|
*
|
|
* Copyright (c) 1989, 1990, 1991 Carnegie Mellon University
|
|
* All Rights Reserved.
|
|
*
|
|
* Author: Alessandro Forin
|
|
*
|
|
* Permission to use, copy, modify and distribute this software and its
|
|
* documentation is hereby granted, provided that both the copyright
|
|
* notice and this permission notice appear in all copies of the
|
|
* software, derivative works or modified versions, and any portions
|
|
* thereof, and that both notices appear in supporting documentation.
|
|
*
|
|
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
|
|
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
|
|
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
|
|
*
|
|
* Carnegie Mellon requests users of this software to return to
|
|
*
|
|
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
|
|
* School of Computer Science
|
|
* Carnegie Mellon University
|
|
* Pittsburgh PA 15213-3890
|
|
*
|
|
* any improvements or extensions that they make and grant Carnegie the
|
|
* rights to redistribute these changes.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "stand.h"
|
|
|
|
off_t
|
|
lseek(int fd, off_t offset, int where)
|
|
{
|
|
off_t bufpos, filepos, target;
|
|
struct open_file *f;
|
|
|
|
f = fd2open_file(fd);
|
|
if (f == NULL || f->f_flags == 0) {
|
|
errno = EBADF;
|
|
return (-1);
|
|
}
|
|
|
|
if (f->f_flags & F_RAW) {
|
|
/*
|
|
* On RAW devices, update internal offset.
|
|
*/
|
|
switch (where) {
|
|
case SEEK_SET:
|
|
f->f_offset = offset;
|
|
break;
|
|
case SEEK_CUR:
|
|
f->f_offset += offset;
|
|
break;
|
|
default:
|
|
errno = EOFFSET;
|
|
return (-1);
|
|
}
|
|
return (f->f_offset);
|
|
}
|
|
|
|
/*
|
|
* If there is some unconsumed data in the readahead buffer and it
|
|
* contains the desired offset, simply adjust the buffer offset and
|
|
* length. We don't bother with SEEK_END here, since the code to
|
|
* handle it would fail in the same cases where the non-readahead
|
|
* code fails (namely, for streams which cannot seek backward and whose
|
|
* size isn't known in advance).
|
|
*/
|
|
if (f->f_ralen != 0 && where != SEEK_END) {
|
|
filepos = (f->f_ops->fo_seek)(f, 0, SEEK_CUR);
|
|
if (filepos == -1)
|
|
return (-1);
|
|
bufpos = filepos - f->f_ralen;
|
|
switch (where) {
|
|
case SEEK_SET:
|
|
target = offset;
|
|
break;
|
|
case SEEK_CUR:
|
|
target = bufpos + offset;
|
|
break;
|
|
default:
|
|
errno = EINVAL;
|
|
return (-1);
|
|
}
|
|
if (bufpos <= target && target < filepos) {
|
|
f->f_raoffset += target - bufpos;
|
|
f->f_ralen -= target - bufpos;
|
|
return (target);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If this is a relative seek, we need to correct the offset for
|
|
* bytes that we have already read but the caller doesn't know
|
|
* about.
|
|
*/
|
|
if (where == SEEK_CUR)
|
|
offset -= f->f_ralen;
|
|
|
|
/*
|
|
* Invalidate the readahead buffer.
|
|
*/
|
|
f->f_ralen = 0;
|
|
|
|
return (f->f_ops->fo_seek)(f, offset, where);
|
|
}
|