Stefan Roese | 2fc10f6 | 2009-03-19 15:35:05 +0100 | [diff] [blame^] | 1 | /* |
| 2 | * This file is part of UBIFS. |
| 3 | * |
| 4 | * Copyright (C) 2006-2008 Nokia Corporation. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of the GNU General Public License version 2 as published by |
| 8 | * the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 13 | * more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License along with |
| 16 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
| 17 | * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | * |
| 19 | * Authors: Artem Bityutskiy (Битюцкий Артём) |
| 20 | * Adrian Hunter |
| 21 | */ |
| 22 | |
| 23 | /* |
| 24 | * This file is a part of UBIFS journal implementation and contains various |
| 25 | * functions which manipulate the log. The log is a fixed area on the flash |
| 26 | * which does not contain any data but refers to buds. The log is a part of the |
| 27 | * journal. |
| 28 | */ |
| 29 | |
| 30 | #include "ubifs.h" |
| 31 | |
| 32 | /** |
| 33 | * ubifs_search_bud - search bud LEB. |
| 34 | * @c: UBIFS file-system description object |
| 35 | * @lnum: logical eraseblock number to search |
| 36 | * |
| 37 | * This function searches bud LEB @lnum. Returns bud description object in case |
| 38 | * of success and %NULL if there is no bud with this LEB number. |
| 39 | */ |
| 40 | struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum) |
| 41 | { |
| 42 | struct rb_node *p; |
| 43 | struct ubifs_bud *bud; |
| 44 | |
| 45 | spin_lock(&c->buds_lock); |
| 46 | p = c->buds.rb_node; |
| 47 | while (p) { |
| 48 | bud = rb_entry(p, struct ubifs_bud, rb); |
| 49 | if (lnum < bud->lnum) |
| 50 | p = p->rb_left; |
| 51 | else if (lnum > bud->lnum) |
| 52 | p = p->rb_right; |
| 53 | else { |
| 54 | spin_unlock(&c->buds_lock); |
| 55 | return bud; |
| 56 | } |
| 57 | } |
| 58 | spin_unlock(&c->buds_lock); |
| 59 | return NULL; |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list. |
| 64 | * @c: UBIFS file-system description object |
| 65 | * @bud: the bud to add |
| 66 | */ |
| 67 | void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud) |
| 68 | { |
| 69 | struct rb_node **p, *parent = NULL; |
| 70 | struct ubifs_bud *b; |
| 71 | struct ubifs_jhead *jhead; |
| 72 | |
| 73 | spin_lock(&c->buds_lock); |
| 74 | p = &c->buds.rb_node; |
| 75 | while (*p) { |
| 76 | parent = *p; |
| 77 | b = rb_entry(parent, struct ubifs_bud, rb); |
| 78 | ubifs_assert(bud->lnum != b->lnum); |
| 79 | if (bud->lnum < b->lnum) |
| 80 | p = &(*p)->rb_left; |
| 81 | else |
| 82 | p = &(*p)->rb_right; |
| 83 | } |
| 84 | |
| 85 | rb_link_node(&bud->rb, parent, p); |
| 86 | rb_insert_color(&bud->rb, &c->buds); |
| 87 | if (c->jheads) { |
| 88 | jhead = &c->jheads[bud->jhead]; |
| 89 | list_add_tail(&bud->list, &jhead->buds_list); |
| 90 | } else |
| 91 | ubifs_assert(c->replaying && (c->vfs_sb->s_flags & MS_RDONLY)); |
| 92 | |
| 93 | /* |
| 94 | * Note, although this is a new bud, we anyway account this space now, |
| 95 | * before any data has been written to it, because this is about to |
| 96 | * guarantee fixed mount time, and this bud will anyway be read and |
| 97 | * scanned. |
| 98 | */ |
| 99 | c->bud_bytes += c->leb_size - bud->start; |
| 100 | |
| 101 | dbg_log("LEB %d:%d, jhead %d, bud_bytes %lld", bud->lnum, |
| 102 | bud->start, bud->jhead, c->bud_bytes); |
| 103 | spin_unlock(&c->buds_lock); |
| 104 | } |