From 9eefe2a2b37a838558e3d213a9f5519503d0c180 Mon Sep 17 00:00:00 2001 From: Stefan Roese Date: Thu, 19 Mar 2009 15:35:05 +0100 Subject: UBIFS: Implement read-only UBIFS support in U-Boot The U-Boot UBIFS implementation is largely a direct copy from the current Linux version (2.6.29-rc6). As already done in the UBI version we have an "abstraction layer" to redefine or remove some OS calls (e.g. mutex_lock() ...). This makes it possible to use the original Linux code with very little changes. And by this we can better update to later Linux versions. I removed some of the Linux features that are not used in the U-Boot version (e.g. garbage-collection, write support). Signed-off-by: Stefan Roese CC: Artem Bityutskiy CC: Adrian Hunter --- fs/ubifs/log.c | 104 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 fs/ubifs/log.c (limited to 'fs/ubifs/log.c') diff --git a/fs/ubifs/log.c b/fs/ubifs/log.c new file mode 100644 index 0000000000..68a9bd98f8 --- /dev/null +++ b/fs/ubifs/log.c @@ -0,0 +1,104 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * 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., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file is a part of UBIFS journal implementation and contains various + * functions which manipulate the log. The log is a fixed area on the flash + * which does not contain any data but refers to buds. The log is a part of the + * journal. + */ + +#include "ubifs.h" + +/** + * ubifs_search_bud - search bud LEB. + * @c: UBIFS file-system description object + * @lnum: logical eraseblock number to search + * + * This function searches bud LEB @lnum. Returns bud description object in case + * of success and %NULL if there is no bud with this LEB number. + */ +struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum) +{ + struct rb_node *p; + struct ubifs_bud *bud; + + spin_lock(&c->buds_lock); + p = c->buds.rb_node; + while (p) { + bud = rb_entry(p, struct ubifs_bud, rb); + if (lnum < bud->lnum) + p = p->rb_left; + else if (lnum > bud->lnum) + p = p->rb_right; + else { + spin_unlock(&c->buds_lock); + return bud; + } + } + spin_unlock(&c->buds_lock); + return NULL; +} + +/** + * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list. + * @c: UBIFS file-system description object + * @bud: the bud to add + */ +void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud) +{ + struct rb_node **p, *parent = NULL; + struct ubifs_bud *b; + struct ubifs_jhead *jhead; + + spin_lock(&c->buds_lock); + p = &c->buds.rb_node; + while (*p) { + parent = *p; + b = rb_entry(parent, struct ubifs_bud, rb); + ubifs_assert(bud->lnum != b->lnum); + if (bud->lnum < b->lnum) + p = &(*p)->rb_left; + else + p = &(*p)->rb_right; + } + + rb_link_node(&bud->rb, parent, p); + rb_insert_color(&bud->rb, &c->buds); + if (c->jheads) { + jhead = &c->jheads[bud->jhead]; + list_add_tail(&bud->list, &jhead->buds_list); + } else + ubifs_assert(c->replaying && (c->vfs_sb->s_flags & MS_RDONLY)); + + /* + * Note, although this is a new bud, we anyway account this space now, + * before any data has been written to it, because this is about to + * guarantee fixed mount time, and this bud will anyway be read and + * scanned. + */ + c->bud_bytes += c->leb_size - bud->start; + + dbg_log("LEB %d:%d, jhead %d, bud_bytes %lld", bud->lnum, + bud->start, bud->jhead, c->bud_bytes); + spin_unlock(&c->buds_lock); +} -- cgit v1.2.1