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Message-Id: <1210070159-22794-7-git-send-email-Artem.Bityutskiy@nokia.com>
Date: Tue, 6 May 2008 13:35:37 +0300
From: Artem Bityutskiy <Artem.Bityutskiy@...ia.com>
To: LKML <linux-kernel@...r.kernel.org>
Cc: Adrian Hunter <ext-adrian.hunter@...ia.com>,
Artem Bityutskiy <Artem.Bityutskiy@...ia.com>
Subject: [PATCH take 2 06/28] UBIFS: add journal replay
The journal re-play subsystem is responsible for replaying the
journal during mount if it was not committed before last un-mount.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@...ia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@...ia.com>
---
fs/ubifs/replay.c | 1008 +++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 1008 insertions(+), 0 deletions(-)
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
new file mode 100644
index 0000000..c24e0de
--- /dev/null
+++ b/fs/ubifs/replay.c
@@ -0,0 +1,1008 @@
+/*
+ * 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: Adrian Hunter
+ * Artem Bityutskiy (Битюцкий Артём)
+ */
+
+/*
+ * This file contains journal replay code. It runs when the file-system is being
+ * mounted and requires no locking.
+ *
+ * The larger is the journal, the longer it takes to scan it, so the longer it
+ * takes to mount UBIFS. This is why the journal has limited size which may be
+ * changed depending on the system requirements. But a larger journal gives
+ * faster I/O speed because it writes the index less frequently. So this is a
+ * trade-off. Also, the journal is indexed by the in-memory index (TNC), so the
+ * larger is the journal, the more memory its index may consume.
+ */
+
+#include "ubifs.h"
+
+/*
+ * Replay flags.
+ *
+ * REPLAY_DELETION: node was deleted
+ * REPLAY_REF: node is a reference node
+ */
+enum {
+ REPLAY_DELETION = 1,
+ REPLAY_REF = 2,
+};
+
+/**
+ * struct replay_entry - replay tree entry.
+ * @lnum: logical eraseblock number of the node
+ * @offs: node offset
+ * @len: node length
+ * @sqnum: node sequence number
+ * @flags: replay flags
+ * @rb: links the replay tree
+ * @key: node key
+ * @nm: directory entry name
+ * @old_size: truncation old size
+ * @new_size: truncation new size
+ * @free: amount of free space in a bud
+ * @dirty: amount of dirty space in a bud from padding and deletion nodes
+ *
+ * UBIFS journal replay must compare node sequence numbers, which means it must
+ * build a tree of node information to insert into the TNC.
+ */
+struct replay_entry {
+ int lnum;
+ int offs;
+ int len;
+ unsigned long long sqnum;
+ int flags;
+ struct rb_node rb;
+ union ubifs_key key;
+ union {
+ struct qstr nm;
+ struct {
+ loff_t old_size;
+ loff_t new_size;
+ };
+ struct {
+ int free;
+ int dirty;
+ };
+ };
+};
+
+/**
+ * struct bud_entry - entry in the list of buds to replay.
+ * @list: next bud in the list
+ * @bud: bud description object
+ * @free: free bytes in the bud
+ * @sqnum: reference node sequence number
+ */
+struct bud_entry {
+ struct list_head list;
+ struct ubifs_bud *bud;
+ int free;
+ unsigned long long sqnum;
+};
+
+/**
+ * set_bud_lprops - set free and dirty space used by a bud.
+ * @c: UBIFS file-system description object
+ * @r: replay entry of bud
+ */
+static int set_bud_lprops(struct ubifs_info *c, struct replay_entry *r)
+{
+ const struct ubifs_lprops *lp;
+ int err = 0, dirty;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, r->lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ dirty = lp->dirty;
+ if (r->offs == 0 && (lp->free != c->leb_size || lp->dirty != 0)) {
+ dbg_mnt("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum,
+ lp->free, lp->dirty);
+ dbg_gc("bud LEB %d was GC'd (%d free, %d dirty)", r->lnum,
+ lp->free, lp->dirty);
+ dirty -= c->leb_size - lp->free;
+ if (dirty != 0)
+ dbg_msg("LEB %d lp: %d free %d dirty "
+ "replay: %d free %d dirty", r->lnum, lp->free,
+ lp->dirty, r->free, r->dirty);
+ }
+ lp = ubifs_change_lp(c, lp, r->free, dirty + r->dirty,
+ lp->flags | LPROPS_TAKEN, 0);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * trun_remove_range - apply a replay entry for a truncation to the TNC.
+ * @c: UBIFS file-system description object
+ * @r: replay entry of truncation
+ */
+static int trun_remove_range(struct ubifs_info *c, struct replay_entry *r)
+{
+ unsigned min_blk, max_blk;
+ union ubifs_key min_key, max_key;
+ ino_t ino;
+
+ min_blk = r->new_size / UBIFS_BLOCK_SIZE;
+ if (r->new_size & (UBIFS_BLOCK_SIZE - 1))
+ min_blk += 1;
+
+ max_blk = r->old_size / UBIFS_BLOCK_SIZE;
+ if ((r->old_size & (UBIFS_BLOCK_SIZE - 1)) == 0)
+ max_blk -= 1;
+
+ ino = key_ino(c, &r->key);
+
+ data_key_init(c, &min_key, ino, min_blk);
+ data_key_init(c, &max_key, ino, max_blk);
+
+ return ubifs_tnc_remove_range(c, &min_key, &max_key);
+}
+
+/**
+ * apply_replay_entry - apply a replay entry to the TNC.
+ * @c: UBIFS file-system description object
+ * @r: replay entry to apply
+ *
+ * Apply a replay entry to the TNC.
+ */
+static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
+{
+ int err, deletion = ((r->flags & REPLAY_DELETION) != 0);
+
+ dbg_mnt("LEB %d:%d len %d flgs %d sqnum %llu %s", r->lnum,
+ r->offs, r->len, r->flags, r->sqnum, DBGKEY(&r->key));
+ /*
+ * Set c->replay_sqnum to help 'fallible_read_node()' identify dangling
+ * branches.
+ */
+ c->replay_sqnum = r->sqnum;
+ if (r->flags & REPLAY_REF)
+ err = set_bud_lprops(c, r);
+ else if (is_hash_key(c, &r->key)) {
+ if (deletion)
+ err = ubifs_tnc_remove_nm(c, &r->key, &r->nm);
+ else
+ err = ubifs_tnc_add_nm(c, &r->key, r->lnum, r->offs,
+ r->len, &r->nm);
+ } else {
+ if (deletion)
+ switch (key_type(c, &r->key)) {
+ case UBIFS_INO_KEY:
+ {
+ ino_t inum = key_ino(c, &r->key);
+
+ err = ubifs_tnc_remove_ino(c, inum);
+ break;
+ }
+ case UBIFS_TRUN_KEY:
+ err = trun_remove_range(c, r);
+ break;
+ default:
+ err = ubifs_tnc_remove(c, &r->key);
+ break;
+ }
+ else
+ err = ubifs_tnc_add(c, &r->key, r->lnum, r->offs,
+ r->len);
+ if (err)
+ return err;
+
+ if (c->need_recovery)
+ err = ubifs_recover_size_accum(c, &r->key, deletion,
+ r->new_size);
+ }
+
+ return err;
+}
+
+/**
+ * destroy_replay_tree - destroy the replay.
+ * @c: UBIFS file-system description object
+ *
+ * Destroy the replay tree.
+ */
+static void destroy_replay_tree(struct ubifs_info *c)
+{
+ struct rb_node *this = c->replay_tree.rb_node;
+ struct replay_entry *r;
+
+ while (this) {
+ if (this->rb_left) {
+ this = this->rb_left;
+ continue;
+ } else if (this->rb_right) {
+ this = this->rb_right;
+ continue;
+ }
+ r = rb_entry(this, struct replay_entry, rb);
+ this = rb_parent(this);
+ if (this) {
+ if (this->rb_left == &r->rb)
+ this->rb_left = NULL;
+ else
+ this->rb_right = NULL;
+ }
+ if (key_type(c, &r->key) == UBIFS_DENT_KEY)
+ kfree(r->nm.name);
+ kfree(r);
+ }
+ c->replay_tree = RB_ROOT;
+}
+
+/**
+ * apply_replay_tree - apply the replay tree to the TNC.
+ * @c: UBIFS file-system description object
+ *
+ * Apply the replay tree.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int apply_replay_tree(struct ubifs_info *c)
+{
+ struct rb_node *this = rb_first(&c->replay_tree);
+
+ while (this) {
+ struct replay_entry *r;
+ int err;
+
+ cond_resched();
+
+ r = rb_entry(this, struct replay_entry, rb);
+ err = apply_replay_entry(c, r);
+ if (err)
+ return err;
+ this = rb_next(this);
+ }
+ return 0;
+}
+
+/**
+ * insert_node - insert a node to the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @len: node length
+ * @key: node key
+ * @sqnum: sequence number
+ * @deletion: non-zero if this is a deletion
+ * @used: number of bytes in use in a LEB
+ * @old_size: truncation old size
+ * @new_size: truncation new size
+ *
+ * This function inserts a scanned non-direntry node to the replay tree.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int insert_node(struct ubifs_info *c, int lnum, int offs, int len,
+ union ubifs_key *key, unsigned long long sqnum,
+ int deletion, int *used, loff_t old_size,
+ loff_t new_size)
+{
+ struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+ struct replay_entry *r;
+
+ if (key_ino(c, key) >= c->highest_inum)
+ c->highest_inum = key_ino(c, key);
+
+ dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key));
+ while (*p) {
+ parent = *p;
+ r = rb_entry(parent, struct replay_entry, rb);
+ if (sqnum < r->sqnum) {
+ p = &(*p)->rb_left;
+ continue;
+ } else if (sqnum > r->sqnum) {
+ p = &(*p)->rb_right;
+ continue;
+ }
+ ubifs_err("duplicate sqnum in replay");
+ return -EINVAL;
+ }
+
+ r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+
+ if (!deletion)
+ *used += ALIGN(len, 8);
+ r->lnum = lnum;
+ r->offs = offs;
+ r->len = len;
+ r->sqnum = sqnum;
+ r->flags = (deletion ? REPLAY_DELETION : 0);
+ r->old_size = old_size;
+ r->new_size = new_size;
+ key_copy(c, key, &r->key);
+
+ rb_link_node(&r->rb, parent, p);
+ rb_insert_color(&r->rb, &c->replay_tree);
+ return 0;
+}
+
+/**
+ * insert_dent - insert a directory entry node into the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @len: node length
+ * @key: node key
+ * @name: directory entry name
+ * @nlen: directory entry name length
+ * @sqnum: sequence number
+ * @deletion: non-zero if this is a deletion
+ * @used: number of bytes in use in a LEB
+ *
+ * This function inserts a scanned directory entry node to the replay tree.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ *
+ * This function is also used for extended attribute entries because they are
+ * implemented as directory entry nodes.
+ */
+static int insert_dent(struct ubifs_info *c, int lnum, int offs, int len,
+ union ubifs_key *key, const char *name, int nlen,
+ unsigned long long sqnum, int deletion, int *used)
+{
+ struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+ struct replay_entry *r;
+ char *nbuf;
+
+ if (key_ino(c, key) >= c->highest_inum)
+ c->highest_inum = key_ino(c, key);
+
+ dbg_mnt("add LEB %d:%d, key %s", lnum, offs, DBGKEY(key));
+ while (*p) {
+ parent = *p;
+ r = rb_entry(parent, struct replay_entry, rb);
+ if (sqnum < r->sqnum) {
+ p = &(*p)->rb_left;
+ continue;
+ }
+ if (sqnum > r->sqnum) {
+ p = &(*p)->rb_right;
+ continue;
+ }
+ ubifs_err("duplicate sqnum in replay");
+ return -EINVAL;
+ }
+
+ r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+ nbuf = kmalloc(nlen + 1, GFP_KERNEL);
+ if (!nbuf) {
+ kfree(r);
+ return -ENOMEM;
+ }
+
+ if (!deletion)
+ *used += ALIGN(len, 8);
+ r->lnum = lnum;
+ r->offs = offs;
+ r->len = len;
+ r->sqnum = sqnum;
+ r->nm.len = nlen;
+ memcpy(nbuf, name, nlen);
+ nbuf[nlen] = '\0';
+ r->nm.name = nbuf;
+ r->flags = (deletion ? REPLAY_DELETION : 0);
+ key_copy(c, key, &r->key);
+
+ ubifs_assert(!*p);
+ rb_link_node(&r->rb, parent, p);
+ rb_insert_color(&r->rb, &c->replay_tree);
+ return 0;
+}
+
+/**
+ * replay_bud - replay a bud logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: bud logical eraseblock number to replay
+ * @offs: bud start offset
+ * @jhead: journal head to which this bud belongs
+ * @free: amount of free space in the bud is returned here
+ * @dirty: amount of dirty space from padding and deletion nodes is returned
+ * here
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
+ int *free, int *dirty)
+{
+ int err = 0, used = 0;
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ struct ubifs_bud *bud;
+
+ dbg_mnt("replay bud LEB %d, head %d", lnum, jhead);
+ if (c->need_recovery)
+ sleb = ubifs_recover_leb(c, lnum, offs, c->sbuf, jhead != GCHD);
+ else
+ sleb = ubifs_scan(c, lnum, offs, c->sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+
+ /*
+ * The bud does not have to start from offset zero - the beginning of
+ * the 'lnum' LEB may contain previously committed data. One of the
+ * things we have to do in replay is to correctly update lprops with
+ * newer information about this LEB.
+ *
+ * At this point lprops thinks that this LEB has 'c->leb_size - offs'
+ * bytes of free space because it only contain information about
+ * committed data.
+ *
+ * But we know that real amount of free space is 'c->leb_size -
+ * sleb->endpt', and the space in the 'lnum' LEB between 'offs' and
+ * 'sleb->endpt' is used by bud data. We have to correctly calculate
+ * how much of these data are dirty and update lprops with this
+ * information.
+ *
+ * The dirt in that LEB region is comprised of padding nodes, deletion
+ * nodes, truncation nodes and nodes which are obsoleted by subsequent
+ * nodes in this LEB. So instead of calculating clean space, we
+ * calculate used space ('used' variable).
+ */
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ int deletion = 0;
+
+ cond_resched();
+
+ if (snod->sqnum >= SQNUM_WATERMARK) {
+ ubifs_err("file system's life ended");
+ goto out_dump;
+ }
+
+ if (snod->sqnum > c->max_sqnum)
+ c->max_sqnum = snod->sqnum;
+
+ switch (snod->type) {
+ case UBIFS_INO_NODE:
+ {
+ struct ubifs_ino_node *ino = snod->node;
+ loff_t new_size = le64_to_cpu(ino->size);
+
+ if (le32_to_cpu(ino->nlink) == 0)
+ deletion = 1;
+ err = insert_node(c, lnum, snod->offs, snod->len,
+ &snod->key, snod->sqnum, deletion,
+ &used, 0, new_size);
+ break;
+ }
+ case UBIFS_DATA_NODE:
+ {
+ struct ubifs_data_node *dn = snod->node;
+ loff_t new_size = le32_to_cpu(dn->size) +
+ key_block(c, &snod->key) *
+ UBIFS_BLOCK_SIZE;
+
+ err = insert_node(c, lnum, snod->offs, snod->len,
+ &snod->key, snod->sqnum, deletion,
+ &used, 0, new_size);
+ break;
+ }
+ case UBIFS_DENT_NODE:
+ case UBIFS_XENT_NODE:
+ {
+ struct ubifs_dent_node *dent = snod->node;
+
+ err = ubifs_validate_entry(c, dent);
+ if (err)
+ goto out_dump;
+
+ err = insert_dent(c, lnum, snod->offs, snod->len,
+ &snod->key, dent->name,
+ le16_to_cpu(dent->nlen), snod->sqnum,
+ !le64_to_cpu(dent->inum), &used);
+ break;
+ }
+ case UBIFS_TRUN_NODE:
+ {
+ struct ubifs_trun_node *trun = snod->node;
+ loff_t old_size = le64_to_cpu(trun->old_size);
+ loff_t new_size = le64_to_cpu(trun->new_size);
+
+ /* Validate truncation node */
+ if (old_size < 0 || old_size > c->max_inode_sz ||
+ new_size < 0 || new_size > c->max_inode_sz ||
+ old_size <= new_size) {
+ ubifs_err("bad truncation node");
+ goto out_dump;
+ }
+
+ err = insert_node(c, lnum, snod->offs, snod->len,
+ &snod->key, snod->sqnum, 1, &used,
+ old_size, new_size);
+ break;
+ }
+ default:
+ ubifs_err("unexpected node type %d in bud LEB %d:%d",
+ snod->type, lnum, snod->offs);
+ err = -EINVAL;
+ goto out_dump;
+ }
+ if (err)
+ goto out;
+ }
+
+ bud = ubifs_search_bud(c, lnum);
+ if (!bud)
+ BUG();
+
+ ubifs_assert(sleb->endpt - offs >= used);
+ ubifs_assert(sleb->endpt % c->min_io_size == 0);
+
+ if (sleb->endpt + c->min_io_size <= c->leb_size &&
+ !(c->vfs_sb->s_flags & MS_RDONLY))
+ err = ubifs_wbuf_seek_nolock(&c->jheads[jhead].wbuf, lnum,
+ sleb->endpt, UBI_SHORTTERM);
+
+ *dirty = sleb->endpt - offs - used;
+ *free = c->leb_size - sleb->endpt;
+
+out:
+ ubifs_scan_destroy(sleb);
+ return err;
+
+out_dump:
+ ubifs_err("bad node is at LEB %d:%d", lnum, snod->offs);
+ dbg_dump_node(c, snod->node);
+ ubifs_scan_destroy(sleb);
+ return -EINVAL;
+}
+
+/**
+ * insert_ref_node - insert a ref node to the replay tree.
+ * @c: UBIFS file-system description object
+ * @lnum: node logical eraseblock number
+ * @offs: node offset
+ * @sqnum: sequence number
+ * @free: amount of free space in bud
+ * @dirty: amount of dirty space from padding and deletion nodes
+ */
+static int insert_ref_node(struct ubifs_info *c, int lnum, int offs,
+ unsigned long long sqnum, int free, int dirty)
+{
+ struct rb_node **p = &c->replay_tree.rb_node, *parent = NULL;
+ struct replay_entry *r;
+ union ubifs_key key;
+ int cmp;
+
+ dbg_mnt("add ref LEB %d:%d", lnum, offs);
+ highest_ino_key(c, &key, -1);
+ while (*p) {
+ parent = *p;
+ r = rb_entry(parent, struct replay_entry, rb);
+ cmp = keys_cmp(c, &key, &r->key);
+ if (sqnum < r->sqnum) {
+ p = &(*p)->rb_left;
+ continue;
+ } else if (sqnum > r->sqnum) {
+ p = &(*p)->rb_right;
+ continue;
+ }
+ ubifs_err("duplicate sqnum in r");
+ return -EINVAL;
+ }
+
+ r = kzalloc(sizeof(struct replay_entry), GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+
+ r->lnum = lnum;
+ r->offs = offs;
+ r->sqnum = sqnum;
+ r->flags = REPLAY_REF;
+ r->free = free;
+ r->dirty = dirty;
+ key_copy(c, &key, &r->key);
+
+ rb_link_node(&r->rb, parent, p);
+ rb_insert_color(&r->rb, &c->replay_tree);
+ return 0;
+}
+
+/**
+ * replay_buds - replay all buds.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int replay_buds(struct ubifs_info *c)
+{
+ struct bud_entry *b;
+ int err, uninitialized_var(free), uninitialized_var(dirty);
+
+ list_for_each_entry(b, &c->replay_buds, list) {
+ err = replay_bud(c, b->bud->lnum, b->bud->start, b->bud->jhead,
+ &free, &dirty);
+ if (err)
+ return err;
+ err = insert_ref_node(c, b->bud->lnum, b->bud->start, b->sqnum,
+ free, dirty);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * destroy_bud_list - destroy the list of buds to replay.
+ * @c: UBIFS file-system description object
+ */
+static void destroy_bud_list(struct ubifs_info *c)
+{
+ struct bud_entry *b;
+
+ while (!list_empty(&c->replay_buds)) {
+ b = list_entry(c->replay_buds.next, struct bud_entry, list);
+ list_del(&b->list);
+ kfree(b);
+ }
+}
+
+/**
+ * add_replay_bud - add a bud to the list of buds to replay.
+ * @c: UBIFS file-system description object
+ * @lnum: bud logical eraseblock number to replay
+ * @offs: bud start offset
+ * @jhead: journal head to which this bud belongs
+ * @sqnum: reference node sequence number
+ *
+ * This function returns zero in case of success and a negative error code in
+ * case of failure.
+ */
+static int add_replay_bud(struct ubifs_info *c, int lnum, int offs, int jhead,
+ unsigned long long sqnum)
+{
+ struct ubifs_bud *bud;
+ struct bud_entry *b;
+
+ dbg_mnt("add replay bud LEB %d:%d, head %d", lnum, offs, jhead);
+
+ bud = kmalloc(sizeof(struct ubifs_bud), GFP_KERNEL);
+ if (!bud)
+ return -ENOMEM;
+
+ b = kmalloc(sizeof(struct bud_entry), GFP_KERNEL);
+ if (!b) {
+ kfree(bud);
+ return -ENOMEM;
+ }
+
+ bud->lnum = lnum;
+ bud->start = offs;
+ bud->jhead = jhead;
+ ubifs_add_bud(c, bud);
+
+ b->bud = bud;
+ b->sqnum = sqnum;
+ list_add_tail(&b->list, &c->replay_buds);
+
+ return 0;
+}
+
+/**
+ * validate_ref - validate a reference node.
+ * @c: UBIFS file-system description object
+ * @ref: the reference node to validate
+ * @ref_lnum: LEB number of the reference node
+ * @ref_offs: reference node offset
+ *
+ * This function returns %1 if a bud reference already exists for the LEB. %0 is
+ * returned if the reference node is new, otherwise %-EINVAL is returned if
+ * validation failed.
+ */
+static int validate_ref(struct ubifs_info *c, const struct ubifs_ref_node *ref)
+{
+ struct ubifs_bud *bud;
+ int lnum = le32_to_cpu(ref->lnum);
+ unsigned int offs = le32_to_cpu(ref->offs);
+ unsigned int jhead = le32_to_cpu(ref->jhead);
+
+ /*
+ * ref->offs may point to the end of LEB when the journal head points
+ * to the end of LEB and we write reference node for it during commit.
+ * So this is why we require 'offs > c->leb_size'.
+ */
+ if (jhead >= c->jhead_cnt || lnum >= c->leb_cnt ||
+ lnum < c->main_first || offs > c->leb_size ||
+ offs & (c->min_io_size - 1))
+ return -EINVAL;
+
+ /* Make sure we have not already looked at this bud */
+ bud = ubifs_search_bud(c, lnum);
+ if (bud) {
+ if (bud->jhead == jhead && bud->start <= offs)
+ return 1;
+ ubifs_err("bud at LEB %d:%d was already referred", lnum, offs);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
+ * replay_log_leb - replay a log logical eraseblock.
+ * @c: UBIFS file-system description object
+ * @lnum: log logical eraseblock to replay
+ * @offs: offset to start replaying from
+ * @sbuf: scan buffer
+ *
+ * This function replays a log LEB and returns zero in case of success, %1 if
+ * this is the last LEB in the log, and a negative error code in case of
+ * failure.
+ */
+static int replay_log_leb(struct ubifs_info *c, int lnum, int offs, void *sbuf)
+{
+ int err;
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ const struct ubifs_cs_node *node;
+
+ dbg_mnt("replay log LEB %d:%d", lnum, offs);
+ sleb = ubifs_scan(c, lnum, offs, sbuf);
+ if (IS_ERR(sleb)) {
+ if (c->need_recovery)
+ sleb = ubifs_recover_log_leb(c, lnum, offs, sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+ }
+
+ if (sleb->nodes_cnt == 0) {
+ err = 1;
+ goto out;
+ }
+
+ node = sleb->buf;
+
+ snod = list_entry(sleb->nodes.next, struct ubifs_scan_node, list);
+ if (c->cs_sqnum == 0) {
+ /*
+ * This is the first log LEB we are looking at, make sure that
+ * the first node is a commit start node. Also record its
+ * sequence number so that UBIFS can determine where the log
+ * ends, because all nodes which were have higher sequence
+ * numbers.
+ */
+ if (snod->type != UBIFS_CS_NODE) {
+ dbg_err("first log node at LEB %d:%d is not CS node",
+ lnum, offs);
+ goto out_dump;
+ }
+ if (le64_to_cpu(node->cmt_no) != c->cmt_no) {
+ dbg_err("first CS node at LEB %d:%d has wrong "
+ "commit number %llu expected %llu",
+ lnum, offs, le64_to_cpu(node->cmt_no),
+ c->cmt_no);
+ goto out_dump;
+ }
+
+ c->cs_sqnum = le64_to_cpu(node->ch.sqnum);
+ dbg_mnt("commit start sqnum %llu", c->cs_sqnum);
+ }
+
+ if (snod->sqnum < c->cs_sqnum) {
+ /*
+ * This means that we reached end of log and now
+ * look to the older log data, which was already
+ * committed but the eraseblock was not erased (UBIFS
+ * only unmaps it). So this basically means we have to
+ * exit with "end of log" code.
+ */
+ err = 1;
+ goto out;
+ }
+
+ /* Make sure the first node sits at offset zero of the LEB */
+ if (snod->offs != 0) {
+ dbg_err("first node is not at zero offset");
+ goto out_dump;
+ }
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+
+ cond_resched();
+
+ if (snod->sqnum >= SQNUM_WATERMARK) {
+ ubifs_err("file system's life ended");
+ goto out_dump;
+ }
+
+ if (snod->sqnum < c->cs_sqnum) {
+ dbg_err("bad sqnum %llu, commit sqnum %llu",
+ snod->sqnum, c->cs_sqnum);
+ goto out_dump;
+ }
+
+ if (snod->sqnum > c->max_sqnum)
+ c->max_sqnum = snod->sqnum;
+
+ switch (snod->type) {
+ case UBIFS_REF_NODE: {
+ const struct ubifs_ref_node *ref = snod->node;
+
+ err = validate_ref(c, ref);
+ if (err == 1)
+ break; /* Already have this bud */
+ if (err)
+ goto out_dump;
+
+ err = add_replay_bud(c, le32_to_cpu(ref->lnum),
+ le32_to_cpu(ref->offs),
+ le32_to_cpu(ref->jhead),
+ snod->sqnum);
+ if (err)
+ goto out;
+
+ break;
+ }
+ case UBIFS_CS_NODE:
+ /* Make sure it sits at the beginning of LEB */
+ if (snod->offs != 0) {
+ ubifs_err("unexpected node in log");
+ goto out_dump;
+ }
+ break;
+ default:
+ ubifs_err("unexpected node in log");
+ goto out_dump;
+ }
+ }
+
+ if (sleb->endpt || c->lhead_offs >= c->leb_size) {
+ c->lhead_lnum = lnum;
+ c->lhead_offs = sleb->endpt;
+ }
+
+ err = !sleb->endpt;
+out:
+ ubifs_scan_destroy(sleb);
+ return err;
+
+out_dump:
+ ubifs_err("log error detected while replying the log at LEB %d:%d",
+ lnum, offs + snod->offs);
+ dbg_dump_node(c, snod->node);
+ ubifs_scan_destroy(sleb);
+ return -EINVAL;
+}
+
+/**
+ * take_ihead - update the status of the index head in lprops to 'taken'.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the amount of free space in the index head LEB or a
+ * negative error code.
+ */
+static int take_ihead(struct ubifs_info *c)
+{
+ const struct ubifs_lprops *lp;
+ int err, free;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ free = lp->free;
+
+ lp = ubifs_change_lp(c, lp, -1, -1, lp->flags | LPROPS_TAKEN, 0);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ err = free;
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_replay_journal - replay journal.
+ * @c: UBIFS file-system description object
+ *
+ * This function scans the journal, replays and cleans it up. It makes sure all
+ * memory data structures related to uncommitted journal are built (dirty TNC
+ * tree, tree of buds, modified lprops, etc).
+ */
+int ubifs_replay_journal(struct ubifs_info *c)
+{
+ int err, i, lnum, offs, free;
+ void *sbuf = NULL;
+
+ /* Update the status of the index head in lprops to 'taken' */
+ free = take_ihead(c);
+ if (free < 0)
+ return free; /* Error code */
+
+ if (c->ihead_offs != c->leb_size - free) {
+ ubifs_err("bad index head LEB %d:%d", c->ihead_lnum,
+ c->ihead_offs);
+ return -EINVAL;
+ }
+
+ sbuf = vmalloc(c->leb_size);
+ if (!sbuf)
+ return -ENOMEM;
+
+ dbg_mnt("start replaying the journal");
+
+ c->replaying = 1;
+
+ lnum = c->ltail_lnum = c->lhead_lnum;
+ offs = c->lhead_offs;
+
+ for (i = 0; i < c->log_lebs; i++, lnum++) {
+ if (lnum >= UBIFS_LOG_LNUM + c->log_lebs) {
+ /*
+ * The log is logically circular, we reached the last
+ * LEB, switch to the first one.
+ */
+ lnum = UBIFS_LOG_LNUM;
+ offs = 0;
+ }
+ err = replay_log_leb(c, lnum, offs, sbuf);
+ if (err == 1)
+ /* We hit the end of the log */
+ break;
+ if (err)
+ goto out;
+ offs = 0;
+ }
+
+ err = replay_buds(c);
+ if (err)
+ goto out;
+
+ err = apply_replay_tree(c);
+ if (err)
+ goto out;
+
+ ubifs_assert(c->bud_bytes <= c->max_bud_bytes || c->need_recovery);
+ dbg_mnt("finished, log head LEB %d:%d, max_sqnum %llu, "
+ "highest_inum %lu", c->lhead_lnum, c->lhead_offs, c->max_sqnum,
+ c->highest_inum);
+out:
+ destroy_replay_tree(c);
+ destroy_bud_list(c);
+ vfree(sbuf);
+ c->replaying = 0;
+ return err;
+}
--
1.5.4.1
--
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