diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/ubifs/log.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/ubifs/log.c | 771 |
1 files changed, 0 insertions, 771 deletions
diff --git a/ANDROID_3.4.5/fs/ubifs/log.c b/ANDROID_3.4.5/fs/ubifs/log.c deleted file mode 100644 index f9fd068d..00000000 --- a/ANDROID_3.4.5/fs/ubifs/log.c +++ /dev/null @@ -1,771 +0,0 @@ -/* - * 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" - -#ifdef CONFIG_UBIFS_FS_DEBUG -static int dbg_check_bud_bytes(struct ubifs_info *c); -#else -#define dbg_check_bud_bytes(c) 0 -#endif - -/** - * 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_get_wbuf - get the wbuf associated with a LEB, if there is one. - * @c: UBIFS file-system description object - * @lnum: logical eraseblock number to search - * - * This functions returns the wbuf for @lnum or %NULL if there is not one. - */ -struct ubifs_wbuf *ubifs_get_wbuf(struct ubifs_info *c, int lnum) -{ - struct rb_node *p; - struct ubifs_bud *bud; - int jhead; - - if (!c->jheads) - return NULL; - - 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 { - jhead = bud->jhead; - spin_unlock(&c->buds_lock); - return &c->jheads[jhead].wbuf; - } - } - spin_unlock(&c->buds_lock); - return NULL; -} - -/** - * empty_log_bytes - calculate amount of empty space in the log. - * @c: UBIFS file-system description object - */ -static inline long long empty_log_bytes(const struct ubifs_info *c) -{ - long long h, t; - - h = (long long)c->lhead_lnum * c->leb_size + c->lhead_offs; - t = (long long)c->ltail_lnum * c->leb_size; - - if (h >= t) - return c->log_bytes - h + t; - else - return t - h; -} - -/** - * 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->ro_mount); - - /* - * 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 %s, bud_bytes %lld", bud->lnum, - bud->start, dbg_jhead(bud->jhead), c->bud_bytes); - spin_unlock(&c->buds_lock); -} - -/** - * ubifs_add_bud_to_log - add a new bud to the log. - * @c: UBIFS file-system description object - * @jhead: journal head the bud belongs to - * @lnum: LEB number of the bud - * @offs: starting offset of the bud - * - * This function writes reference node for the new bud LEB @lnum it to the log, - * and adds it to the buds tress. It also makes sure that log size does not - * exceed the 'c->max_bud_bytes' limit. Returns zero in case of success, - * %-EAGAIN if commit is required, and a negative error codes in case of - * failure. - */ -int ubifs_add_bud_to_log(struct ubifs_info *c, int jhead, int lnum, int offs) -{ - int err; - struct ubifs_bud *bud; - struct ubifs_ref_node *ref; - - bud = kmalloc(sizeof(struct ubifs_bud), GFP_NOFS); - if (!bud) - return -ENOMEM; - ref = kzalloc(c->ref_node_alsz, GFP_NOFS); - if (!ref) { - kfree(bud); - return -ENOMEM; - } - - mutex_lock(&c->log_mutex); - ubifs_assert(!c->ro_media && !c->ro_mount); - if (c->ro_error) { - err = -EROFS; - goto out_unlock; - } - - /* Make sure we have enough space in the log */ - if (empty_log_bytes(c) - c->ref_node_alsz < c->min_log_bytes) { - dbg_log("not enough log space - %lld, required %d", - empty_log_bytes(c), c->min_log_bytes); - ubifs_commit_required(c); - err = -EAGAIN; - goto out_unlock; - } - - /* - * Make sure the amount of space in buds will not exceed the - * 'c->max_bud_bytes' limit, because we want to guarantee mount time - * limits. - * - * It is not necessary to hold @c->buds_lock when reading @c->bud_bytes - * because we are holding @c->log_mutex. All @c->bud_bytes take place - * when both @c->log_mutex and @c->bud_bytes are locked. - */ - if (c->bud_bytes + c->leb_size - offs > c->max_bud_bytes) { - dbg_log("bud bytes %lld (%lld max), require commit", - c->bud_bytes, c->max_bud_bytes); - ubifs_commit_required(c); - err = -EAGAIN; - goto out_unlock; - } - - /* - * If the journal is full enough - start background commit. Note, it is - * OK to read 'c->cmt_state' without spinlock because integer reads - * are atomic in the kernel. - */ - if (c->bud_bytes >= c->bg_bud_bytes && - c->cmt_state == COMMIT_RESTING) { - dbg_log("bud bytes %lld (%lld max), initiate BG commit", - c->bud_bytes, c->max_bud_bytes); - ubifs_request_bg_commit(c); - } - - bud->lnum = lnum; - bud->start = offs; - bud->jhead = jhead; - - ref->ch.node_type = UBIFS_REF_NODE; - ref->lnum = cpu_to_le32(bud->lnum); - ref->offs = cpu_to_le32(bud->start); - ref->jhead = cpu_to_le32(jhead); - - if (c->lhead_offs > c->leb_size - c->ref_node_alsz) { - c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); - c->lhead_offs = 0; - } - - if (c->lhead_offs == 0) { - /* Must ensure next log LEB has been unmapped */ - err = ubifs_leb_unmap(c, c->lhead_lnum); - if (err) - goto out_unlock; - } - - if (bud->start == 0) { - /* - * Before writing the LEB reference which refers an empty LEB - * to the log, we have to make sure it is mapped, because - * otherwise we'd risk to refer an LEB with garbage in case of - * an unclean reboot, because the target LEB might have been - * unmapped, but not yet physically erased. - */ - err = ubifs_leb_map(c, bud->lnum, UBI_SHORTTERM); - if (err) - goto out_unlock; - } - - dbg_log("write ref LEB %d:%d", - c->lhead_lnum, c->lhead_offs); - err = ubifs_write_node(c, ref, UBIFS_REF_NODE_SZ, c->lhead_lnum, - c->lhead_offs, UBI_SHORTTERM); - if (err) - goto out_unlock; - - c->lhead_offs += c->ref_node_alsz; - - ubifs_add_bud(c, bud); - - mutex_unlock(&c->log_mutex); - kfree(ref); - return 0; - -out_unlock: - mutex_unlock(&c->log_mutex); - kfree(ref); - kfree(bud); - return err; -} - -/** - * remove_buds - remove used buds. - * @c: UBIFS file-system description object - * - * This function removes use buds from the buds tree. It does not remove the - * buds which are pointed to by journal heads. - */ -static void remove_buds(struct ubifs_info *c) -{ - struct rb_node *p; - - ubifs_assert(list_empty(&c->old_buds)); - c->cmt_bud_bytes = 0; - spin_lock(&c->buds_lock); - p = rb_first(&c->buds); - while (p) { - struct rb_node *p1 = p; - struct ubifs_bud *bud; - struct ubifs_wbuf *wbuf; - - p = rb_next(p); - bud = rb_entry(p1, struct ubifs_bud, rb); - wbuf = &c->jheads[bud->jhead].wbuf; - - if (wbuf->lnum == bud->lnum) { - /* - * Do not remove buds which are pointed to by journal - * heads (non-closed buds). - */ - c->cmt_bud_bytes += wbuf->offs - bud->start; - dbg_log("preserve %d:%d, jhead %s, bud bytes %d, " - "cmt_bud_bytes %lld", bud->lnum, bud->start, - dbg_jhead(bud->jhead), wbuf->offs - bud->start, - c->cmt_bud_bytes); - bud->start = wbuf->offs; - } else { - c->cmt_bud_bytes += c->leb_size - bud->start; - dbg_log("remove %d:%d, jhead %s, bud bytes %d, " - "cmt_bud_bytes %lld", bud->lnum, bud->start, - dbg_jhead(bud->jhead), c->leb_size - bud->start, - c->cmt_bud_bytes); - rb_erase(p1, &c->buds); - /* - * If the commit does not finish, the recovery will need - * to replay the journal, in which case the old buds - * must be unchanged. Do not release them until post - * commit i.e. do not allow them to be garbage - * collected. - */ - list_move(&bud->list, &c->old_buds); - } - } - spin_unlock(&c->buds_lock); -} - -/** - * ubifs_log_start_commit - start commit. - * @c: UBIFS file-system description object - * @ltail_lnum: return new log tail LEB number - * - * The commit operation starts with writing "commit start" node to the log and - * reference nodes for all journal heads which will define new journal after - * the commit has been finished. The commit start and reference nodes are - * written in one go to the nearest empty log LEB (hence, when commit is - * finished UBIFS may safely unmap all the previous log LEBs). This function - * returns zero in case of success and a negative error code in case of - * failure. - */ -int ubifs_log_start_commit(struct ubifs_info *c, int *ltail_lnum) -{ - void *buf; - struct ubifs_cs_node *cs; - struct ubifs_ref_node *ref; - int err, i, max_len, len; - - err = dbg_check_bud_bytes(c); - if (err) - return err; - - max_len = UBIFS_CS_NODE_SZ + c->jhead_cnt * UBIFS_REF_NODE_SZ; - max_len = ALIGN(max_len, c->min_io_size); - buf = cs = kmalloc(max_len, GFP_NOFS); - if (!buf) - return -ENOMEM; - - cs->ch.node_type = UBIFS_CS_NODE; - cs->cmt_no = cpu_to_le64(c->cmt_no); - ubifs_prepare_node(c, cs, UBIFS_CS_NODE_SZ, 0); - - /* - * Note, we do not lock 'c->log_mutex' because this is the commit start - * phase and we are exclusively using the log. And we do not lock - * write-buffer because nobody can write to the file-system at this - * phase. - */ - - len = UBIFS_CS_NODE_SZ; - for (i = 0; i < c->jhead_cnt; i++) { - int lnum = c->jheads[i].wbuf.lnum; - int offs = c->jheads[i].wbuf.offs; - - if (lnum == -1 || offs == c->leb_size) - continue; - - dbg_log("add ref to LEB %d:%d for jhead %s", - lnum, offs, dbg_jhead(i)); - ref = buf + len; - ref->ch.node_type = UBIFS_REF_NODE; - ref->lnum = cpu_to_le32(lnum); - ref->offs = cpu_to_le32(offs); - ref->jhead = cpu_to_le32(i); - - ubifs_prepare_node(c, ref, UBIFS_REF_NODE_SZ, 0); - len += UBIFS_REF_NODE_SZ; - } - - ubifs_pad(c, buf + len, ALIGN(len, c->min_io_size) - len); - - /* Switch to the next log LEB */ - if (c->lhead_offs) { - c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); - c->lhead_offs = 0; - } - - if (c->lhead_offs == 0) { - /* Must ensure next LEB has been unmapped */ - err = ubifs_leb_unmap(c, c->lhead_lnum); - if (err) - goto out; - } - - len = ALIGN(len, c->min_io_size); - dbg_log("writing commit start at LEB %d:0, len %d", c->lhead_lnum, len); - err = ubifs_leb_write(c, c->lhead_lnum, cs, 0, len, UBI_SHORTTERM); - if (err) - goto out; - - *ltail_lnum = c->lhead_lnum; - - c->lhead_offs += len; - if (c->lhead_offs == c->leb_size) { - c->lhead_lnum = ubifs_next_log_lnum(c, c->lhead_lnum); - c->lhead_offs = 0; - } - - remove_buds(c); - - /* - * We have started the commit and now users may use the rest of the log - * for new writes. - */ - c->min_log_bytes = 0; - -out: - kfree(buf); - return err; -} - -/** - * ubifs_log_end_commit - end commit. - * @c: UBIFS file-system description object - * @ltail_lnum: new log tail LEB number - * - * This function is called on when the commit operation was finished. It - * moves log tail to new position and unmaps LEBs which contain obsolete data. - * Returns zero in case of success and a negative error code in case of - * failure. - */ -int ubifs_log_end_commit(struct ubifs_info *c, int ltail_lnum) -{ - int err; - - /* - * At this phase we have to lock 'c->log_mutex' because UBIFS allows FS - * writes during commit. Its only short "commit" start phase when - * writers are blocked. - */ - mutex_lock(&c->log_mutex); - - dbg_log("old tail was LEB %d:0, new tail is LEB %d:0", - c->ltail_lnum, ltail_lnum); - - c->ltail_lnum = ltail_lnum; - /* - * The commit is finished and from now on it must be guaranteed that - * there is always enough space for the next commit. - */ - c->min_log_bytes = c->leb_size; - - spin_lock(&c->buds_lock); - c->bud_bytes -= c->cmt_bud_bytes; - spin_unlock(&c->buds_lock); - - err = dbg_check_bud_bytes(c); - - mutex_unlock(&c->log_mutex); - return err; -} - -/** - * ubifs_log_post_commit - things to do after commit is completed. - * @c: UBIFS file-system description object - * @old_ltail_lnum: old log tail LEB number - * - * Release buds only after commit is completed, because they must be unchanged - * if recovery is needed. - * - * Unmap log LEBs only after commit is completed, because they may be needed for - * recovery. - * - * This function returns %0 on success and a negative error code on failure. - */ -int ubifs_log_post_commit(struct ubifs_info *c, int old_ltail_lnum) -{ - int lnum, err = 0; - - while (!list_empty(&c->old_buds)) { - struct ubifs_bud *bud; - - bud = list_entry(c->old_buds.next, struct ubifs_bud, list); - err = ubifs_return_leb(c, bud->lnum); - if (err) - return err; - list_del(&bud->list); - kfree(bud); - } - mutex_lock(&c->log_mutex); - for (lnum = old_ltail_lnum; lnum != c->ltail_lnum; - lnum = ubifs_next_log_lnum(c, lnum)) { - dbg_log("unmap log LEB %d", lnum); - err = ubifs_leb_unmap(c, lnum); - if (err) - goto out; - } -out: - mutex_unlock(&c->log_mutex); - return err; -} - -/** - * struct done_ref - references that have been done. - * @rb: rb-tree node - * @lnum: LEB number - */ -struct done_ref { - struct rb_node rb; - int lnum; -}; - -/** - * done_already - determine if a reference has been done already. - * @done_tree: rb-tree to store references that have been done - * @lnum: LEB number of reference - * - * This function returns %1 if the reference has been done, %0 if not, otherwise - * a negative error code is returned. - */ -static int done_already(struct rb_root *done_tree, int lnum) -{ - struct rb_node **p = &done_tree->rb_node, *parent = NULL; - struct done_ref *dr; - - while (*p) { - parent = *p; - dr = rb_entry(parent, struct done_ref, rb); - if (lnum < dr->lnum) - p = &(*p)->rb_left; - else if (lnum > dr->lnum) - p = &(*p)->rb_right; - else - return 1; - } - - dr = kzalloc(sizeof(struct done_ref), GFP_NOFS); - if (!dr) - return -ENOMEM; - - dr->lnum = lnum; - - rb_link_node(&dr->rb, parent, p); - rb_insert_color(&dr->rb, done_tree); - - return 0; -} - -/** - * destroy_done_tree - destroy the done tree. - * @done_tree: done tree to destroy - */ -static void destroy_done_tree(struct rb_root *done_tree) -{ - struct rb_node *this = done_tree->rb_node; - struct done_ref *dr; - - while (this) { - if (this->rb_left) { - this = this->rb_left; - continue; - } else if (this->rb_right) { - this = this->rb_right; - continue; - } - dr = rb_entry(this, struct done_ref, rb); - this = rb_parent(this); - if (this) { - if (this->rb_left == &dr->rb) - this->rb_left = NULL; - else - this->rb_right = NULL; - } - kfree(dr); - } -} - -/** - * add_node - add a node to the consolidated log. - * @c: UBIFS file-system description object - * @buf: buffer to which to add - * @lnum: LEB number to which to write is passed and returned here - * @offs: offset to where to write is passed and returned here - * @node: node to add - * - * This function returns %0 on success and a negative error code on failure. - */ -static int add_node(struct ubifs_info *c, void *buf, int *lnum, int *offs, - void *node) -{ - struct ubifs_ch *ch = node; - int len = le32_to_cpu(ch->len), remains = c->leb_size - *offs; - - if (len > remains) { - int sz = ALIGN(*offs, c->min_io_size), err; - - ubifs_pad(c, buf + *offs, sz - *offs); - err = ubifs_leb_change(c, *lnum, buf, sz, UBI_SHORTTERM); - if (err) - return err; - *lnum = ubifs_next_log_lnum(c, *lnum); - *offs = 0; - } - memcpy(buf + *offs, node, len); - *offs += ALIGN(len, 8); - return 0; -} - -/** - * ubifs_consolidate_log - consolidate the log. - * @c: UBIFS file-system description object - * - * Repeated failed commits could cause the log to be full, but at least 1 LEB is - * needed for commit. This function rewrites the reference nodes in the log - * omitting duplicates, and failed CS nodes, and leaving no gaps. - * - * This function returns %0 on success and a negative error code on failure. - */ -int ubifs_consolidate_log(struct ubifs_info *c) -{ - struct ubifs_scan_leb *sleb; - struct ubifs_scan_node *snod; - struct rb_root done_tree = RB_ROOT; - int lnum, err, first = 1, write_lnum, offs = 0; - void *buf; - - dbg_rcvry("log tail LEB %d, log head LEB %d", c->ltail_lnum, - c->lhead_lnum); - buf = vmalloc(c->leb_size); - if (!buf) - return -ENOMEM; - lnum = c->ltail_lnum; - write_lnum = lnum; - while (1) { - sleb = ubifs_scan(c, lnum, 0, c->sbuf, 0); - if (IS_ERR(sleb)) { - err = PTR_ERR(sleb); - goto out_free; - } - list_for_each_entry(snod, &sleb->nodes, list) { - switch (snod->type) { - case UBIFS_REF_NODE: { - struct ubifs_ref_node *ref = snod->node; - int ref_lnum = le32_to_cpu(ref->lnum); - - err = done_already(&done_tree, ref_lnum); - if (err < 0) - goto out_scan; - if (err != 1) { - err = add_node(c, buf, &write_lnum, - &offs, snod->node); - if (err) - goto out_scan; - } - break; - } - case UBIFS_CS_NODE: - if (!first) - break; - err = add_node(c, buf, &write_lnum, &offs, - snod->node); - if (err) - goto out_scan; - first = 0; - break; - } - } - ubifs_scan_destroy(sleb); - if (lnum == c->lhead_lnum) - break; - lnum = ubifs_next_log_lnum(c, lnum); - } - if (offs) { - int sz = ALIGN(offs, c->min_io_size); - - ubifs_pad(c, buf + offs, sz - offs); - err = ubifs_leb_change(c, write_lnum, buf, sz, UBI_SHORTTERM); - if (err) - goto out_free; - offs = ALIGN(offs, c->min_io_size); - } - destroy_done_tree(&done_tree); - vfree(buf); - if (write_lnum == c->lhead_lnum) { - ubifs_err("log is too full"); - return -EINVAL; - } - /* Unmap remaining LEBs */ - lnum = write_lnum; - do { - lnum = ubifs_next_log_lnum(c, lnum); - err = ubifs_leb_unmap(c, lnum); - if (err) - return err; - } while (lnum != c->lhead_lnum); - c->lhead_lnum = write_lnum; - c->lhead_offs = offs; - dbg_rcvry("new log head at %d:%d", c->lhead_lnum, c->lhead_offs); - return 0; - -out_scan: - ubifs_scan_destroy(sleb); -out_free: - destroy_done_tree(&done_tree); - vfree(buf); - return err; -} - -#ifdef CONFIG_UBIFS_FS_DEBUG - -/** - * dbg_check_bud_bytes - make sure bud bytes calculation are all right. - * @c: UBIFS file-system description object - * - * This function makes sure the amount of flash space used by closed buds - * ('c->bud_bytes' is correct). Returns zero in case of success and %-EINVAL in - * case of failure. - */ -static int dbg_check_bud_bytes(struct ubifs_info *c) -{ - int i, err = 0; - struct ubifs_bud *bud; - long long bud_bytes = 0; - - if (!dbg_is_chk_gen(c)) - return 0; - - spin_lock(&c->buds_lock); - for (i = 0; i < c->jhead_cnt; i++) - list_for_each_entry(bud, &c->jheads[i].buds_list, list) - bud_bytes += c->leb_size - bud->start; - - if (c->bud_bytes != bud_bytes) { - ubifs_err("bad bud_bytes %lld, calculated %lld", - c->bud_bytes, bud_bytes); - err = -EINVAL; - } - spin_unlock(&c->buds_lock); - - return err; -} - -#endif /* CONFIG_UBIFS_FS_DEBUG */ |