freebsd-dev/sys/cddl/boot/zfs/lzjb.c

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Update ZFS from version 6 to 13 and bring some FreeBSD-specific changes. This bring huge amount of changes, I'll enumerate only user-visible changes: - Delegated Administration Allows regular users to perform ZFS operations, like file system creation, snapshot creation, etc. - L2ARC Level 2 cache for ZFS - allows to use additional disks for cache. Huge performance improvements mostly for random read of mostly static content. - slog Allow to use additional disks for ZFS Intent Log to speed up operations like fsync(2). - vfs.zfs.super_owner Allows regular users to perform privileged operations on files stored on ZFS file systems owned by him. Very careful with this one. - chflags(2) Not all the flags are supported. This still needs work. - ZFSBoot Support to boot off of ZFS pool. Not finished, AFAIK. Submitted by: dfr - Snapshot properties - New failure modes Before if write requested failed, system paniced. Now one can select from one of three failure modes: - panic - panic on write error - wait - wait for disk to reappear - continue - serve read requests if possible, block write requests - Refquota, refreservation properties Just quota and reservation properties, but don't count space consumed by children file systems, clones and snapshots. - Sparse volumes ZVOLs that don't reserve space in the pool. - External attributes Compatible with extattr(2). - NFSv4-ACLs Not sure about the status, might not be complete yet. Submitted by: trasz - Creation-time properties - Regression tests for zpool(8) command. Obtained from: OpenSolaris
2008-11-17 20:49:29 +00:00
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*#pragma ident "%Z%%M% %I% %E% SMI"*/
/*
* We keep our own copy of this algorithm for 2 main reasons:
* 1. If we didn't, anyone modifying common/os/compress.c would
* directly break our on disk format
* 2. Our version of lzjb does not have a number of checks that the
* common/os version needs and uses
* In particular, we are adding the "feature" that compress() can
* take a destination buffer size and return -1 if the data will not
* compress to d_len or less.
*/
#define MATCH_BITS 6
#define MATCH_MIN 3
#define MATCH_MAX ((1 << MATCH_BITS) + (MATCH_MIN - 1))
#define OFFSET_MASK ((1 << (16 - MATCH_BITS)) - 1)
#define LEMPEL_SIZE 256
/*ARGSUSED*/
static int
lzjb_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
{
unsigned char *src = s_start;
unsigned char *dst = d_start;
unsigned char *d_end = (unsigned char *)d_start + d_len;
unsigned char *cpy, copymap = 0;
int copymask = 1 << (NBBY - 1);
while (dst < d_end) {
if ((copymask <<= 1) == (1 << NBBY)) {
copymask = 1;
copymap = *src++;
}
if (copymap & copymask) {
int mlen = (src[0] >> (NBBY - MATCH_BITS)) + MATCH_MIN;
int offset = ((src[0] << NBBY) | src[1]) & OFFSET_MASK;
src += 2;
if ((cpy = dst - offset) < (unsigned char *)d_start)
return (-1);
while (--mlen >= 0 && dst < d_end)
*dst++ = *cpy++;
} else {
*dst++ = *src++;
}
}
return (0);
}