tmp_suning_uos_patched/fs/9p/error.c
Latchesar Ionkov 531b1094b7 [PATCH] v9fs: zero copy implementation
Performance enhancement reducing the number of copies in the data and
stat paths.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:14:06 -08:00

95 lines
2.3 KiB
C

/*
* linux/fs/9p/error.c
*
* Error string handling
*
* Plan 9 uses error strings, Unix uses error numbers. These functions
* try to help manage that and provide for dynamically adding error
* mappings.
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* 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.
*
* 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:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/jhash.h>
#include "debug.h"
#include "error.h"
/**
* v9fs_error_init - preload
* @errstr: error string
*
*/
int v9fs_error_init(void)
{
struct errormap *c;
int bucket;
/* initialize hash table */
for (bucket = 0; bucket < ERRHASHSZ; bucket++)
INIT_HLIST_HEAD(&hash_errmap[bucket]);
/* load initial error map into hash table */
for (c = errmap; c->name != NULL; c++) {
c->namelen = strlen(c->name);
bucket = jhash(c->name, c->namelen, 0) % ERRHASHSZ;
INIT_HLIST_NODE(&c->list);
hlist_add_head(&c->list, &hash_errmap[bucket]);
}
return 1;
}
/**
* errstr2errno - convert error string to error number
* @errstr: error string
*
*/
int v9fs_errstr2errno(char *errstr, int len)
{
int errno = 0;
struct hlist_node *p = NULL;
struct errormap *c = NULL;
int bucket = jhash(errstr, len, 0) % ERRHASHSZ;
hlist_for_each_entry(c, p, &hash_errmap[bucket], list) {
if (c->namelen==len && !memcmp(c->name, errstr, len)) {
errno = c->val;
break;
}
}
if (errno == 0) {
/* TODO: if error isn't found, add it dynamically */
printk(KERN_ERR "%s: errstr :%s: not found\n", __FUNCTION__,
errstr);
errno = 1;
}
return -errno;
}