[U-Boot] [PATCH 3/8 v2] UBIFS: Implement read-only UBIFS support in U-Boot (Part 3)
Stefan Roese
sr at denx.de
Thu Mar 12 14:56:07 CET 2009
This patchset adds UBIFS read-only support to U-Boot. The following
commands are implemented:
- ubifsmount
Mount an UBIFS volume
- ubifsls
List a directory of the mounted UBIFS volume
- ubifsload
Load a file from the mounted UBIFS volume to memory
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 <sr at denx.de>
CC: Artem Bityutskiy <dedekind at infradead.org>
CC: Adrian Hunter <ext-Adrian.Hunter at nokia.com>
---
Changes in v2:
- Now symbolic links are handled correctly
fs/ubifs/master.c | 341 ++++++++++++++
fs/ubifs/misc.h | 310 +++++++++++++
fs/ubifs/orphan.c | 316 +++++++++++++
fs/ubifs/recovery.c | 1249 +++++++++++++++++++++++++++++++++++++++++++++++++++
fs/ubifs/replay.c | 1070 +++++++++++++++++++++++++++++++++++++++++++
5 files changed, 3286 insertions(+), 0 deletions(-)
create mode 100644 fs/ubifs/master.c
create mode 100644 fs/ubifs/misc.h
create mode 100644 fs/ubifs/orphan.c
create mode 100644 fs/ubifs/recovery.c
create mode 100644 fs/ubifs/replay.c
diff --git a/fs/ubifs/master.c b/fs/ubifs/master.c
new file mode 100644
index 0000000..3f2926e
--- /dev/null
+++ b/fs/ubifs/master.c
@@ -0,0 +1,341 @@
+/*
+ * 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 Ðртём)
+ * Adrian Hunter
+ */
+
+/* This file implements reading and writing the master node */
+
+#include "ubifs.h"
+
+/**
+ * scan_for_master - search the valid master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function scans the master node LEBs and search for the latest master
+ * node. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static int scan_for_master(struct ubifs_info *c)
+{
+ struct ubifs_scan_leb *sleb;
+ struct ubifs_scan_node *snod;
+ int lnum, offs = 0, nodes_cnt;
+
+ lnum = UBIFS_MST_LNUM;
+
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+ nodes_cnt = sleb->nodes_cnt;
+ if (nodes_cnt > 0) {
+ snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
+ list);
+ if (snod->type != UBIFS_MST_NODE)
+ goto out;
+ memcpy(c->mst_node, snod->node, snod->len);
+ offs = snod->offs;
+ }
+ ubifs_scan_destroy(sleb);
+
+ lnum += 1;
+
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb))
+ return PTR_ERR(sleb);
+ if (sleb->nodes_cnt != nodes_cnt)
+ goto out;
+ if (!sleb->nodes_cnt)
+ goto out;
+ snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node, list);
+ if (snod->type != UBIFS_MST_NODE)
+ goto out;
+ if (snod->offs != offs)
+ goto out;
+ if (memcmp((void *)c->mst_node + UBIFS_CH_SZ,
+ (void *)snod->node + UBIFS_CH_SZ,
+ UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
+ goto out;
+ c->mst_offs = offs;
+ ubifs_scan_destroy(sleb);
+ return 0;
+
+out:
+ ubifs_scan_destroy(sleb);
+ return -EINVAL;
+}
+
+/**
+ * validate_master - validate master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function validates data which was read from master node. Returns zero
+ * if the data is all right and %-EINVAL if not.
+ */
+static int validate_master(const struct ubifs_info *c)
+{
+ long long main_sz;
+ int err;
+
+ if (c->max_sqnum >= SQNUM_WATERMARK) {
+ err = 1;
+ goto out;
+ }
+
+ if (c->cmt_no >= c->max_sqnum) {
+ err = 2;
+ goto out;
+ }
+
+ if (c->highest_inum >= INUM_WATERMARK) {
+ err = 3;
+ goto out;
+ }
+
+ if (c->lhead_lnum < UBIFS_LOG_LNUM ||
+ c->lhead_lnum >= UBIFS_LOG_LNUM + c->log_lebs ||
+ c->lhead_offs < 0 || c->lhead_offs >= c->leb_size ||
+ c->lhead_offs & (c->min_io_size - 1)) {
+ err = 4;
+ goto out;
+ }
+
+ if (c->zroot.lnum >= c->leb_cnt || c->zroot.lnum < c->main_first ||
+ c->zroot.offs >= c->leb_size || c->zroot.offs & 7) {
+ err = 5;
+ goto out;
+ }
+
+ if (c->zroot.len < c->ranges[UBIFS_IDX_NODE].min_len ||
+ c->zroot.len > c->ranges[UBIFS_IDX_NODE].max_len) {
+ err = 6;
+ goto out;
+ }
+
+ if (c->gc_lnum >= c->leb_cnt || c->gc_lnum < c->main_first) {
+ err = 7;
+ goto out;
+ }
+
+ if (c->ihead_lnum >= c->leb_cnt || c->ihead_lnum < c->main_first ||
+ c->ihead_offs % c->min_io_size || c->ihead_offs < 0 ||
+ c->ihead_offs > c->leb_size || c->ihead_offs & 7) {
+ err = 8;
+ goto out;
+ }
+
+ main_sz = (long long)c->main_lebs * c->leb_size;
+ if (c->old_idx_sz & 7 || c->old_idx_sz >= main_sz) {
+ err = 9;
+ goto out;
+ }
+
+ if (c->lpt_lnum < c->lpt_first || c->lpt_lnum > c->lpt_last ||
+ c->lpt_offs < 0 || c->lpt_offs + c->nnode_sz > c->leb_size) {
+ err = 10;
+ goto out;
+ }
+
+ if (c->nhead_lnum < c->lpt_first || c->nhead_lnum > c->lpt_last ||
+ c->nhead_offs < 0 || c->nhead_offs % c->min_io_size ||
+ c->nhead_offs > c->leb_size) {
+ err = 11;
+ goto out;
+ }
+
+ if (c->ltab_lnum < c->lpt_first || c->ltab_lnum > c->lpt_last ||
+ c->ltab_offs < 0 ||
+ c->ltab_offs + c->ltab_sz > c->leb_size) {
+ err = 12;
+ goto out;
+ }
+
+ if (c->big_lpt && (c->lsave_lnum < c->lpt_first ||
+ c->lsave_lnum > c->lpt_last || c->lsave_offs < 0 ||
+ c->lsave_offs + c->lsave_sz > c->leb_size)) {
+ err = 13;
+ goto out;
+ }
+
+ if (c->lscan_lnum < c->main_first || c->lscan_lnum >= c->leb_cnt) {
+ err = 14;
+ goto out;
+ }
+
+ if (c->lst.empty_lebs < 0 || c->lst.empty_lebs > c->main_lebs - 2) {
+ err = 15;
+ goto out;
+ }
+
+ if (c->lst.idx_lebs < 0 || c->lst.idx_lebs > c->main_lebs - 1) {
+ err = 16;
+ goto out;
+ }
+
+ if (c->lst.total_free < 0 || c->lst.total_free > main_sz ||
+ c->lst.total_free & 7) {
+ err = 17;
+ goto out;
+ }
+
+ if (c->lst.total_dirty < 0 || (c->lst.total_dirty & 7)) {
+ err = 18;
+ goto out;
+ }
+
+ if (c->lst.total_used < 0 || (c->lst.total_used & 7)) {
+ err = 19;
+ goto out;
+ }
+
+ if (c->lst.total_free + c->lst.total_dirty +
+ c->lst.total_used > main_sz) {
+ err = 20;
+ goto out;
+ }
+
+ if (c->lst.total_dead + c->lst.total_dark +
+ c->lst.total_used + c->old_idx_sz > main_sz) {
+ err = 21;
+ goto out;
+ }
+
+ if (c->lst.total_dead < 0 ||
+ c->lst.total_dead > c->lst.total_free + c->lst.total_dirty ||
+ c->lst.total_dead & 7) {
+ err = 22;
+ goto out;
+ }
+
+ if (c->lst.total_dark < 0 ||
+ c->lst.total_dark > c->lst.total_free + c->lst.total_dirty ||
+ c->lst.total_dark & 7) {
+ err = 23;
+ goto out;
+ }
+
+ return 0;
+
+out:
+ ubifs_err("bad master node at offset %d error %d", c->mst_offs, err);
+ dbg_dump_node(c, c->mst_node);
+ return -EINVAL;
+}
+
+/**
+ * ubifs_read_master - read master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function finds and reads the master node during file-system mount. If
+ * the flash is empty, it creates default master node as well. Returns zero in
+ * case of success and a negative error code in case of failure.
+ */
+int ubifs_read_master(struct ubifs_info *c)
+{
+ int err, old_leb_cnt;
+
+ c->mst_node = kzalloc(c->mst_node_alsz, GFP_KERNEL);
+ if (!c->mst_node)
+ return -ENOMEM;
+
+ err = scan_for_master(c);
+ if (err) {
+ err = ubifs_recover_master_node(c);
+ if (err)
+ /*
+ * Note, we do not free 'c->mst_node' here because the
+ * unmount routine will take care of this.
+ */
+ return err;
+ }
+
+ /* Make sure that the recovery flag is clear */
+ c->mst_node->flags &= cpu_to_le32(~UBIFS_MST_RCVRY);
+
+ c->max_sqnum = le64_to_cpu(c->mst_node->ch.sqnum);
+ c->highest_inum = le64_to_cpu(c->mst_node->highest_inum);
+ c->cmt_no = le64_to_cpu(c->mst_node->cmt_no);
+ c->zroot.lnum = le32_to_cpu(c->mst_node->root_lnum);
+ c->zroot.offs = le32_to_cpu(c->mst_node->root_offs);
+ c->zroot.len = le32_to_cpu(c->mst_node->root_len);
+ c->lhead_lnum = le32_to_cpu(c->mst_node->log_lnum);
+ c->gc_lnum = le32_to_cpu(c->mst_node->gc_lnum);
+ c->ihead_lnum = le32_to_cpu(c->mst_node->ihead_lnum);
+ c->ihead_offs = le32_to_cpu(c->mst_node->ihead_offs);
+ c->old_idx_sz = le64_to_cpu(c->mst_node->index_size);
+ c->lpt_lnum = le32_to_cpu(c->mst_node->lpt_lnum);
+ c->lpt_offs = le32_to_cpu(c->mst_node->lpt_offs);
+ c->nhead_lnum = le32_to_cpu(c->mst_node->nhead_lnum);
+ c->nhead_offs = le32_to_cpu(c->mst_node->nhead_offs);
+ c->ltab_lnum = le32_to_cpu(c->mst_node->ltab_lnum);
+ c->ltab_offs = le32_to_cpu(c->mst_node->ltab_offs);
+ c->lsave_lnum = le32_to_cpu(c->mst_node->lsave_lnum);
+ c->lsave_offs = le32_to_cpu(c->mst_node->lsave_offs);
+ c->lscan_lnum = le32_to_cpu(c->mst_node->lscan_lnum);
+ c->lst.empty_lebs = le32_to_cpu(c->mst_node->empty_lebs);
+ c->lst.idx_lebs = le32_to_cpu(c->mst_node->idx_lebs);
+ old_leb_cnt = le32_to_cpu(c->mst_node->leb_cnt);
+ c->lst.total_free = le64_to_cpu(c->mst_node->total_free);
+ c->lst.total_dirty = le64_to_cpu(c->mst_node->total_dirty);
+ c->lst.total_used = le64_to_cpu(c->mst_node->total_used);
+ c->lst.total_dead = le64_to_cpu(c->mst_node->total_dead);
+ c->lst.total_dark = le64_to_cpu(c->mst_node->total_dark);
+
+ c->calc_idx_sz = c->old_idx_sz;
+
+ if (c->mst_node->flags & cpu_to_le32(UBIFS_MST_NO_ORPHS))
+ c->no_orphs = 1;
+
+ if (old_leb_cnt != c->leb_cnt) {
+ /* The file system has been resized */
+ int growth = c->leb_cnt - old_leb_cnt;
+
+ if (c->leb_cnt < old_leb_cnt ||
+ c->leb_cnt < UBIFS_MIN_LEB_CNT) {
+ ubifs_err("bad leb_cnt on master node");
+ dbg_dump_node(c, c->mst_node);
+ return -EINVAL;
+ }
+
+ dbg_mnt("Auto resizing (master) from %d LEBs to %d LEBs",
+ old_leb_cnt, c->leb_cnt);
+ c->lst.empty_lebs += growth;
+ c->lst.total_free += growth * (long long)c->leb_size;
+ c->lst.total_dark += growth * (long long)c->dark_wm;
+
+ /*
+ * Reflect changes back onto the master node. N.B. the master
+ * node gets written immediately whenever mounting (or
+ * remounting) in read-write mode, so we do not need to write it
+ * here.
+ */
+ c->mst_node->leb_cnt = cpu_to_le32(c->leb_cnt);
+ c->mst_node->empty_lebs = cpu_to_le32(c->lst.empty_lebs);
+ c->mst_node->total_free = cpu_to_le64(c->lst.total_free);
+ c->mst_node->total_dark = cpu_to_le64(c->lst.total_dark);
+ }
+
+ err = validate_master(c);
+ if (err)
+ return err;
+
+ err = dbg_old_index_check_init(c, &c->zroot);
+
+ return err;
+}
diff --git a/fs/ubifs/misc.h b/fs/ubifs/misc.h
new file mode 100644
index 0000000..b745d86
--- /dev/null
+++ b/fs/ubifs/misc.h
@@ -0,0 +1,310 @@
+/*
+ * 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 Ðртём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file contains miscellaneous helper functions.
+ */
+
+#ifndef __UBIFS_MISC_H__
+#define __UBIFS_MISC_H__
+
+/**
+ * ubifs_zn_dirty - check if znode is dirty.
+ * @znode: znode to check
+ *
+ * This helper function returns %1 if @znode is dirty and %0 otherwise.
+ */
+static inline int ubifs_zn_dirty(const struct ubifs_znode *znode)
+{
+ return !!test_bit(DIRTY_ZNODE, &znode->flags);
+}
+
+/**
+ * ubifs_wake_up_bgt - wake up background thread.
+ * @c: UBIFS file-system description object
+ */
+static inline void ubifs_wake_up_bgt(struct ubifs_info *c)
+{
+ if (c->bgt && !c->need_bgt) {
+ c->need_bgt = 1;
+ wake_up_process(c->bgt);
+ }
+}
+
+/**
+ * ubifs_tnc_find_child - find next child in znode.
+ * @znode: znode to search at
+ * @start: the zbranch index to start at
+ *
+ * This helper function looks for znode child starting at index @start. Returns
+ * the child or %NULL if no children were found.
+ */
+static inline struct ubifs_znode *
+ubifs_tnc_find_child(struct ubifs_znode *znode, int start)
+{
+ while (start < znode->child_cnt) {
+ if (znode->zbranch[start].znode)
+ return znode->zbranch[start].znode;
+ start += 1;
+ }
+
+ return NULL;
+}
+
+/**
+ * ubifs_inode - get UBIFS inode information by VFS 'struct inode' object.
+ * @inode: the VFS 'struct inode' pointer
+ */
+static inline struct ubifs_inode *ubifs_inode(const struct inode *inode)
+{
+ return container_of(inode, struct ubifs_inode, vfs_inode);
+}
+
+/**
+ * ubifs_compr_present - check if compressor was compiled in.
+ * @compr_type: compressor type to check
+ *
+ * This function returns %1 of compressor of type @compr_type is present, and
+ * %0 if not.
+ */
+static inline int ubifs_compr_present(int compr_type)
+{
+ ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
+ return !!ubifs_compressors[compr_type]->capi_name;
+}
+
+/**
+ * ubifs_compr_name - get compressor name string by its type.
+ * @compr_type: compressor type
+ *
+ * This function returns compressor type string.
+ */
+static inline const char *ubifs_compr_name(int compr_type)
+{
+ ubifs_assert(compr_type >= 0 && compr_type < UBIFS_COMPR_TYPES_CNT);
+ return ubifs_compressors[compr_type]->name;
+}
+
+/**
+ * ubifs_wbuf_sync - synchronize write-buffer.
+ * @wbuf: write-buffer to synchronize
+ *
+ * This is the same as as 'ubifs_wbuf_sync_nolock()' but it does not assume
+ * that the write-buffer is already locked.
+ */
+static inline int ubifs_wbuf_sync(struct ubifs_wbuf *wbuf)
+{
+ int err;
+
+ mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
+ err = ubifs_wbuf_sync_nolock(wbuf);
+ mutex_unlock(&wbuf->io_mutex);
+ return err;
+}
+
+/**
+ * ubifs_leb_unmap - unmap an LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to unmap
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_unmap(const struct ubifs_info *c, int lnum)
+{
+ int err;
+
+ if (c->ro_media)
+ return -EROFS;
+ err = ubi_leb_unmap(c->ubi, lnum);
+ if (err) {
+ ubifs_err("unmap LEB %d failed, error %d", lnum, err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_leb_write - write to a LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to write
+ * @buf: buffer to write from
+ * @offs: offset within LEB to write to
+ * @len: length to write
+ * @dtype: data type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_write(const struct ubifs_info *c, int lnum,
+ const void *buf, int offs, int len, int dtype)
+{
+ int err;
+
+ if (c->ro_media)
+ return -EROFS;
+ err = ubi_leb_write(c->ubi, lnum, buf, offs, len, dtype);
+ if (err) {
+ ubifs_err("writing %d bytes at %d:%d, error %d",
+ len, lnum, offs, err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_leb_change - atomic LEB change.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to write
+ * @buf: buffer to write from
+ * @len: length to write
+ * @dtype: data type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static inline int ubifs_leb_change(const struct ubifs_info *c, int lnum,
+ const void *buf, int len, int dtype)
+{
+ int err;
+
+ if (c->ro_media)
+ return -EROFS;
+ err = ubi_leb_change(c->ubi, lnum, buf, len, dtype);
+ if (err) {
+ ubifs_err("changing %d bytes in LEB %d, error %d",
+ len, lnum, err);
+ return err;
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_add_dirt - add dirty space to LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to add dirty space for
+ * @dirty: dirty space to add
+ *
+ * This is a helper function which increased amount of dirty LEB space. Returns
+ * zero in case of success and a negative error code in case of failure.
+ */
+static inline int ubifs_add_dirt(struct ubifs_info *c, int lnum, int dirty)
+{
+ return ubifs_update_one_lp(c, lnum, LPROPS_NC, dirty, 0, 0);
+}
+
+/**
+ * ubifs_return_leb - return LEB to lprops.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to return
+ *
+ * This helper function cleans the "taken" flag of a logical eraseblock in the
+ * lprops. Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+static inline int ubifs_return_leb(struct ubifs_info *c, int lnum)
+{
+ return ubifs_change_one_lp(c, lnum, LPROPS_NC, LPROPS_NC, 0,
+ LPROPS_TAKEN, 0);
+}
+
+/**
+ * ubifs_idx_node_sz - return index node size.
+ * @c: the UBIFS file-system description object
+ * @child_cnt: number of children of this index node
+ */
+static inline int ubifs_idx_node_sz(const struct ubifs_info *c, int child_cnt)
+{
+ return UBIFS_IDX_NODE_SZ + (UBIFS_BRANCH_SZ + c->key_len) * child_cnt;
+}
+
+/**
+ * ubifs_idx_branch - return pointer to an index branch.
+ * @c: the UBIFS file-system description object
+ * @idx: index node
+ * @bnum: branch number
+ */
+static inline
+struct ubifs_branch *ubifs_idx_branch(const struct ubifs_info *c,
+ const struct ubifs_idx_node *idx,
+ int bnum)
+{
+ return (struct ubifs_branch *)((void *)idx->branches +
+ (UBIFS_BRANCH_SZ + c->key_len) * bnum);
+}
+
+/**
+ * ubifs_idx_key - return pointer to an index key.
+ * @c: the UBIFS file-system description object
+ * @idx: index node
+ */
+static inline void *ubifs_idx_key(const struct ubifs_info *c,
+ const struct ubifs_idx_node *idx)
+{
+ return (void *)((struct ubifs_branch *)idx->branches)->key;
+}
+
+/**
+ * ubifs_tnc_lookup - look up a file-system node.
+ * @c: UBIFS file-system description object
+ * @key: node key to lookup
+ * @node: the node is returned here
+ *
+ * This function look up and reads node with key @key. The caller has to make
+ * sure the @node buffer is large enough to fit the node. Returns zero in case
+ * of success, %-ENOENT if the node was not found, and a negative error code in
+ * case of failure.
+ */
+static inline int ubifs_tnc_lookup(struct ubifs_info *c,
+ const union ubifs_key *key, void *node)
+{
+ return ubifs_tnc_locate(c, key, node, NULL, NULL);
+}
+
+/**
+ * ubifs_get_lprops - get reference to LEB properties.
+ * @c: the UBIFS file-system description object
+ *
+ * This function locks lprops. Lprops have to be unlocked by
+ * 'ubifs_release_lprops()'.
+ */
+static inline void ubifs_get_lprops(struct ubifs_info *c)
+{
+ mutex_lock(&c->lp_mutex);
+}
+
+/**
+ * ubifs_release_lprops - release lprops lock.
+ * @c: the UBIFS file-system description object
+ *
+ * This function has to be called after each 'ubifs_get_lprops()' call to
+ * unlock lprops.
+ */
+static inline void ubifs_release_lprops(struct ubifs_info *c)
+{
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+ ubifs_assert(c->lst.empty_lebs >= 0 &&
+ c->lst.empty_lebs <= c->main_lebs);
+ mutex_unlock(&c->lp_mutex);
+}
+
+#endif /* __UBIFS_MISC_H__ */
diff --git a/fs/ubifs/orphan.c b/fs/ubifs/orphan.c
new file mode 100644
index 0000000..d091031
--- /dev/null
+++ b/fs/ubifs/orphan.c
@@ -0,0 +1,316 @@
+/*
+ * 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
+ *
+ * Author: Adrian Hunter
+ */
+
+#include "ubifs.h"
+
+/*
+ * An orphan is an inode number whose inode node has been committed to the index
+ * with a link count of zero. That happens when an open file is deleted
+ * (unlinked) and then a commit is run. In the normal course of events the inode
+ * would be deleted when the file is closed. However in the case of an unclean
+ * unmount, orphans need to be accounted for. After an unclean unmount, the
+ * orphans' inodes must be deleted which means either scanning the entire index
+ * looking for them, or keeping a list on flash somewhere. This unit implements
+ * the latter approach.
+ *
+ * The orphan area is a fixed number of LEBs situated between the LPT area and
+ * the main area. The number of orphan area LEBs is specified when the file
+ * system is created. The minimum number is 1. The size of the orphan area
+ * should be so that it can hold the maximum number of orphans that are expected
+ * to ever exist at one time.
+ *
+ * The number of orphans that can fit in a LEB is:
+ *
+ * (c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64)
+ *
+ * For example: a 15872 byte LEB can fit 1980 orphans so 1 LEB may be enough.
+ *
+ * Orphans are accumulated in a rb-tree. When an inode's link count drops to
+ * zero, the inode number is added to the rb-tree. It is removed from the tree
+ * when the inode is deleted. Any new orphans that are in the orphan tree when
+ * the commit is run, are written to the orphan area in 1 or more orphan nodes.
+ * If the orphan area is full, it is consolidated to make space. There is
+ * always enough space because validation prevents the user from creating more
+ * than the maximum number of orphans allowed.
+ */
+
+/**
+ * tot_avail_orphs - calculate total space.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns the number of orphans that can be written in half
+ * the total space. That leaves half the space for adding new orphans.
+ */
+static int tot_avail_orphs(struct ubifs_info *c)
+{
+ int avail_lebs, avail;
+
+ avail_lebs = c->orph_lebs;
+ avail = avail_lebs *
+ ((c->leb_size - UBIFS_ORPH_NODE_SZ) / sizeof(__le64));
+ return avail / 2;
+}
+
+/**
+ * ubifs_clear_orphans - erase all LEBs used for orphans.
+ * @c: UBIFS file-system description object
+ *
+ * If recovery is not required, then the orphans from the previous session
+ * are not needed. This function locates the LEBs used to record
+ * orphans, and un-maps them.
+ */
+int ubifs_clear_orphans(struct ubifs_info *c)
+{
+ int lnum, err;
+
+ for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ }
+ c->ohead_lnum = c->orph_first;
+ c->ohead_offs = 0;
+ return 0;
+}
+
+/**
+ * insert_dead_orphan - insert an orphan.
+ * @c: UBIFS file-system description object
+ * @inum: orphan inode number
+ *
+ * This function is a helper to the 'do_kill_orphans()' function. The orphan
+ * must be kept until the next commit, so it is added to the rb-tree and the
+ * deletion list.
+ */
+static int insert_dead_orphan(struct ubifs_info *c, ino_t inum)
+{
+ struct ubifs_orphan *orphan, *o;
+ struct rb_node **p, *parent = NULL;
+
+ orphan = kzalloc(sizeof(struct ubifs_orphan), GFP_KERNEL);
+ if (!orphan)
+ return -ENOMEM;
+ orphan->inum = inum;
+
+ p = &c->orph_tree.rb_node;
+ while (*p) {
+ parent = *p;
+ o = rb_entry(parent, struct ubifs_orphan, rb);
+ if (inum < o->inum)
+ p = &(*p)->rb_left;
+ else if (inum > o->inum)
+ p = &(*p)->rb_right;
+ else {
+ /* Already added - no problem */
+ kfree(orphan);
+ return 0;
+ }
+ }
+ c->tot_orphans += 1;
+ rb_link_node(&orphan->rb, parent, p);
+ rb_insert_color(&orphan->rb, &c->orph_tree);
+ list_add_tail(&orphan->list, &c->orph_list);
+ orphan->dnext = c->orph_dnext;
+ c->orph_dnext = orphan;
+ dbg_mnt("ino %lu, new %d, tot %d", (unsigned long)inum,
+ c->new_orphans, c->tot_orphans);
+ return 0;
+}
+
+/**
+ * do_kill_orphans - remove orphan inodes from the index.
+ * @c: UBIFS file-system description object
+ * @sleb: scanned LEB
+ * @last_cmt_no: cmt_no of last orphan node read is passed and returned here
+ * @outofdate: whether the LEB is out of date is returned here
+ * @last_flagged: whether the end orphan node is encountered
+ *
+ * This function is a helper to the 'kill_orphans()' function. It goes through
+ * every orphan node in a LEB and for every inode number recorded, removes
+ * all keys for that inode from the TNC.
+ */
+static int do_kill_orphans(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ unsigned long long *last_cmt_no, int *outofdate,
+ int *last_flagged)
+{
+ struct ubifs_scan_node *snod;
+ struct ubifs_orph_node *orph;
+ unsigned long long cmt_no;
+ ino_t inum;
+ int i, n, err, first = 1;
+
+ list_for_each_entry(snod, &sleb->nodes, list) {
+ if (snod->type != UBIFS_ORPH_NODE) {
+ ubifs_err("invalid node type %d in orphan area at "
+ "%d:%d", snod->type, sleb->lnum, snod->offs);
+ dbg_dump_node(c, snod->node);
+ return -EINVAL;
+ }
+
+ orph = snod->node;
+
+ /* Check commit number */
+ cmt_no = le64_to_cpu(orph->cmt_no) & LLONG_MAX;
+ /*
+ * The commit number on the master node may be less, because
+ * of a failed commit. If there are several failed commits in a
+ * row, the commit number written on orphan nodes will continue
+ * to increase (because the commit number is adjusted here) even
+ * though the commit number on the master node stays the same
+ * because the master node has not been re-written.
+ */
+ if (cmt_no > c->cmt_no)
+ c->cmt_no = cmt_no;
+ if (cmt_no < *last_cmt_no && *last_flagged) {
+ /*
+ * The last orphan node had a higher commit number and
+ * was flagged as the last written for that commit
+ * number. That makes this orphan node, out of date.
+ */
+ if (!first) {
+ ubifs_err("out of order commit number %llu in "
+ "orphan node at %d:%d",
+ cmt_no, sleb->lnum, snod->offs);
+ dbg_dump_node(c, snod->node);
+ return -EINVAL;
+ }
+ dbg_rcvry("out of date LEB %d", sleb->lnum);
+ *outofdate = 1;
+ return 0;
+ }
+
+ if (first)
+ first = 0;
+
+ n = (le32_to_cpu(orph->ch.len) - UBIFS_ORPH_NODE_SZ) >> 3;
+ for (i = 0; i < n; i++) {
+ inum = le64_to_cpu(orph->inos[i]);
+ dbg_rcvry("deleting orphaned inode %lu",
+ (unsigned long)inum);
+ err = ubifs_tnc_remove_ino(c, inum);
+ if (err)
+ return err;
+ err = insert_dead_orphan(c, inum);
+ if (err)
+ return err;
+ }
+
+ *last_cmt_no = cmt_no;
+ if (le64_to_cpu(orph->cmt_no) & (1ULL << 63)) {
+ dbg_rcvry("last orph node for commit %llu at %d:%d",
+ cmt_no, sleb->lnum, snod->offs);
+ *last_flagged = 1;
+ } else
+ *last_flagged = 0;
+ }
+
+ return 0;
+}
+
+/**
+ * kill_orphans - remove all orphan inodes from the index.
+ * @c: UBIFS file-system description object
+ *
+ * If recovery is required, then orphan inodes recorded during the previous
+ * session (which ended with an unclean unmount) must be deleted from the index.
+ * This is done by updating the TNC, but since the index is not updated until
+ * the next commit, the LEBs where the orphan information is recorded are not
+ * erased until the next commit.
+ */
+static int kill_orphans(struct ubifs_info *c)
+{
+ unsigned long long last_cmt_no = 0;
+ int lnum, err = 0, outofdate = 0, last_flagged = 0;
+
+ c->ohead_lnum = c->orph_first;
+ c->ohead_offs = 0;
+ /* Check no-orphans flag and skip this if no orphans */
+ if (c->no_orphs) {
+ dbg_rcvry("no orphans");
+ return 0;
+ }
+ /*
+ * Orph nodes always start at c->orph_first and are written to each
+ * successive LEB in turn. Generally unused LEBs will have been unmapped
+ * but may contain out of date orphan nodes if the unmap didn't go
+ * through. In addition, the last orphan node written for each commit is
+ * marked (top bit of orph->cmt_no is set to 1). It is possible that
+ * there are orphan nodes from the next commit (i.e. the commit did not
+ * complete successfully). In that case, no orphans will have been lost
+ * due to the way that orphans are written, and any orphans added will
+ * be valid orphans anyway and so can be deleted.
+ */
+ for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
+ struct ubifs_scan_leb *sleb;
+
+ dbg_rcvry("LEB %d", lnum);
+ sleb = ubifs_scan(c, lnum, 0, c->sbuf);
+ if (IS_ERR(sleb)) {
+ sleb = ubifs_recover_leb(c, lnum, 0, c->sbuf, 0);
+ if (IS_ERR(sleb)) {
+ err = PTR_ERR(sleb);
+ break;
+ }
+ }
+ err = do_kill_orphans(c, sleb, &last_cmt_no, &outofdate,
+ &last_flagged);
+ if (err || outofdate) {
+ ubifs_scan_destroy(sleb);
+ break;
+ }
+ if (sleb->endpt) {
+ c->ohead_lnum = lnum;
+ c->ohead_offs = sleb->endpt;
+ }
+ ubifs_scan_destroy(sleb);
+ }
+ return err;
+}
+
+/**
+ * ubifs_mount_orphans - delete orphan inodes and erase LEBs that recorded them.
+ * @c: UBIFS file-system description object
+ * @unclean: indicates recovery from unclean unmount
+ * @read_only: indicates read only mount
+ *
+ * This function is called when mounting to erase orphans from the previous
+ * session. If UBIFS was not unmounted cleanly, then the inodes recorded as
+ * orphans are deleted.
+ */
+int ubifs_mount_orphans(struct ubifs_info *c, int unclean, int read_only)
+{
+ int err = 0;
+
+ c->max_orphans = tot_avail_orphs(c);
+
+ if (!read_only) {
+ c->orph_buf = vmalloc(c->leb_size);
+ if (!c->orph_buf)
+ return -ENOMEM;
+ }
+
+ if (unclean)
+ err = kill_orphans(c);
+ else if (!read_only)
+ err = ubifs_clear_orphans(c);
+
+ return err;
+}
diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
new file mode 100644
index 0000000..fe3b364
--- /dev/null
+++ b/fs/ubifs/recovery.c
@@ -0,0 +1,1249 @@
+/*
+ * 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 Ðртём)
+ */
+
+/*
+ * This file implements functions needed to recover from unclean un-mounts.
+ * When UBIFS is mounted, it checks a flag on the master node to determine if
+ * an un-mount was completed sucessfully. If not, the process of mounting
+ * incorparates additional checking and fixing of on-flash data structures.
+ * UBIFS always cleans away all remnants of an unclean un-mount, so that
+ * errors do not accumulate. However UBIFS defers recovery if it is mounted
+ * read-only, and the flash is not modified in that case.
+ */
+
+#include "ubifs.h"
+
+/**
+ * is_empty - determine whether a buffer is empty (contains all 0xff).
+ * @buf: buffer to clean
+ * @len: length of buffer
+ *
+ * This function returns %1 if the buffer is empty (contains all 0xff) otherwise
+ * %0 is returned.
+ */
+static int is_empty(void *buf, int len)
+{
+ uint8_t *p = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ if (*p++ != 0xff)
+ return 0;
+ return 1;
+}
+
+/**
+ * get_master_node - get the last valid master node allowing for corruption.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @pbuf: buffer containing the LEB read, is returned here
+ * @mst: master node, if found, is returned here
+ * @cor: corruption, if found, is returned here
+ *
+ * This function allocates a buffer, reads the LEB into it, and finds and
+ * returns the last valid master node allowing for one area of corruption.
+ * The corrupt area, if there is one, must be consistent with the assumption
+ * that it is the result of an unclean unmount while the master node was being
+ * written. Under those circumstances, it is valid to use the previously written
+ * master node.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int get_master_node(const struct ubifs_info *c, int lnum, void **pbuf,
+ struct ubifs_mst_node **mst, void **cor)
+{
+ const int sz = c->mst_node_alsz;
+ int err, offs, len;
+ void *sbuf, *buf;
+
+ sbuf = vmalloc(c->leb_size);
+ if (!sbuf)
+ return -ENOMEM;
+
+ err = ubi_read(c->ubi, lnum, sbuf, 0, c->leb_size);
+ if (err && err != -EBADMSG)
+ goto out_free;
+
+ /* Find the first position that is definitely not a node */
+ offs = 0;
+ buf = sbuf;
+ len = c->leb_size;
+ while (offs + UBIFS_MST_NODE_SZ <= c->leb_size) {
+ struct ubifs_ch *ch = buf;
+
+ if (le32_to_cpu(ch->magic) != UBIFS_NODE_MAGIC)
+ break;
+ offs += sz;
+ buf += sz;
+ len -= sz;
+ }
+ /* See if there was a valid master node before that */
+ if (offs) {
+ int ret;
+
+ offs -= sz;
+ buf -= sz;
+ len += sz;
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+ if (ret != SCANNED_A_NODE && offs) {
+ /* Could have been corruption so check one place back */
+ offs -= sz;
+ buf -= sz;
+ len += sz;
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+ if (ret != SCANNED_A_NODE)
+ /*
+ * We accept only one area of corruption because
+ * we are assuming that it was caused while
+ * trying to write a master node.
+ */
+ goto out_err;
+ }
+ if (ret == SCANNED_A_NODE) {
+ struct ubifs_ch *ch = buf;
+
+ if (ch->node_type != UBIFS_MST_NODE)
+ goto out_err;
+ dbg_rcvry("found a master node at %d:%d", lnum, offs);
+ *mst = buf;
+ offs += sz;
+ buf += sz;
+ len -= sz;
+ }
+ }
+ /* Check for corruption */
+ if (offs < c->leb_size) {
+ if (!is_empty(buf, min_t(int, len, sz))) {
+ *cor = buf;
+ dbg_rcvry("found corruption at %d:%d", lnum, offs);
+ }
+ offs += sz;
+ buf += sz;
+ len -= sz;
+ }
+ /* Check remaining empty space */
+ if (offs < c->leb_size)
+ if (!is_empty(buf, len))
+ goto out_err;
+ *pbuf = sbuf;
+ return 0;
+
+out_err:
+ err = -EINVAL;
+out_free:
+ vfree(sbuf);
+ *mst = NULL;
+ *cor = NULL;
+ return err;
+}
+
+/**
+ * write_rcvrd_mst_node - write recovered master node.
+ * @c: UBIFS file-system description object
+ * @mst: master node
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int write_rcvrd_mst_node(struct ubifs_info *c,
+ struct ubifs_mst_node *mst)
+{
+ int err = 0, lnum = UBIFS_MST_LNUM, sz = c->mst_node_alsz;
+ __le32 save_flags;
+
+ dbg_rcvry("recovery");
+
+ save_flags = mst->flags;
+ mst->flags |= cpu_to_le32(UBIFS_MST_RCVRY);
+
+ ubifs_prepare_node(c, mst, UBIFS_MST_NODE_SZ, 1);
+ err = ubi_leb_change(c->ubi, lnum, mst, sz, UBI_SHORTTERM);
+ if (err)
+ goto out;
+ err = ubi_leb_change(c->ubi, lnum + 1, mst, sz, UBI_SHORTTERM);
+ if (err)
+ goto out;
+out:
+ mst->flags = save_flags;
+ return err;
+}
+
+/**
+ * ubifs_recover_master_node - recover the master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function recovers the master node from corruption that may occur due to
+ * an unclean unmount.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_master_node(struct ubifs_info *c)
+{
+ void *buf1 = NULL, *buf2 = NULL, *cor1 = NULL, *cor2 = NULL;
+ struct ubifs_mst_node *mst1 = NULL, *mst2 = NULL, *mst;
+ const int sz = c->mst_node_alsz;
+ int err, offs1, offs2;
+
+ dbg_rcvry("recovery");
+
+ err = get_master_node(c, UBIFS_MST_LNUM, &buf1, &mst1, &cor1);
+ if (err)
+ goto out_free;
+
+ err = get_master_node(c, UBIFS_MST_LNUM + 1, &buf2, &mst2, &cor2);
+ if (err)
+ goto out_free;
+
+ if (mst1) {
+ offs1 = (void *)mst1 - buf1;
+ if ((le32_to_cpu(mst1->flags) & UBIFS_MST_RCVRY) &&
+ (offs1 == 0 && !cor1)) {
+ /*
+ * mst1 was written by recovery at offset 0 with no
+ * corruption.
+ */
+ dbg_rcvry("recovery recovery");
+ mst = mst1;
+ } else if (mst2) {
+ offs2 = (void *)mst2 - buf2;
+ if (offs1 == offs2) {
+ /* Same offset, so must be the same */
+ if (memcmp((void *)mst1 + UBIFS_CH_SZ,
+ (void *)mst2 + UBIFS_CH_SZ,
+ UBIFS_MST_NODE_SZ - UBIFS_CH_SZ))
+ goto out_err;
+ mst = mst1;
+ } else if (offs2 + sz == offs1) {
+ /* 1st LEB was written, 2nd was not */
+ if (cor1)
+ goto out_err;
+ mst = mst1;
+ } else if (offs1 == 0 && offs2 + sz >= c->leb_size) {
+ /* 1st LEB was unmapped and written, 2nd not */
+ if (cor1)
+ goto out_err;
+ mst = mst1;
+ } else
+ goto out_err;
+ } else {
+ /*
+ * 2nd LEB was unmapped and about to be written, so
+ * there must be only one master node in the first LEB
+ * and no corruption.
+ */
+ if (offs1 != 0 || cor1)
+ goto out_err;
+ mst = mst1;
+ }
+ } else {
+ if (!mst2)
+ goto out_err;
+ /*
+ * 1st LEB was unmapped and about to be written, so there must
+ * be no room left in 2nd LEB.
+ */
+ offs2 = (void *)mst2 - buf2;
+ if (offs2 + sz + sz <= c->leb_size)
+ goto out_err;
+ mst = mst2;
+ }
+
+ dbg_rcvry("recovered master node from LEB %d",
+ (mst == mst1 ? UBIFS_MST_LNUM : UBIFS_MST_LNUM + 1));
+
+ memcpy(c->mst_node, mst, UBIFS_MST_NODE_SZ);
+
+ if ((c->vfs_sb->s_flags & MS_RDONLY)) {
+ /* Read-only mode. Keep a copy for switching to rw mode */
+ c->rcvrd_mst_node = kmalloc(sz, GFP_KERNEL);
+ if (!c->rcvrd_mst_node) {
+ err = -ENOMEM;
+ goto out_free;
+ }
+ memcpy(c->rcvrd_mst_node, c->mst_node, UBIFS_MST_NODE_SZ);
+ }
+
+ vfree(buf2);
+ vfree(buf1);
+
+ return 0;
+
+out_err:
+ err = -EINVAL;
+out_free:
+ ubifs_err("failed to recover master node");
+ if (mst1) {
+ dbg_err("dumping first master node");
+ dbg_dump_node(c, mst1);
+ }
+ if (mst2) {
+ dbg_err("dumping second master node");
+ dbg_dump_node(c, mst2);
+ }
+ vfree(buf2);
+ vfree(buf1);
+ return err;
+}
+
+/**
+ * ubifs_write_rcvrd_mst_node - write the recovered master node.
+ * @c: UBIFS file-system description object
+ *
+ * This function writes the master node that was recovered during mounting in
+ * read-only mode and must now be written because we are remounting rw.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_write_rcvrd_mst_node(struct ubifs_info *c)
+{
+ int err;
+
+ if (!c->rcvrd_mst_node)
+ return 0;
+ c->rcvrd_mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+ c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
+ err = write_rcvrd_mst_node(c, c->rcvrd_mst_node);
+ if (err)
+ return err;
+ kfree(c->rcvrd_mst_node);
+ c->rcvrd_mst_node = NULL;
+ return 0;
+}
+
+/**
+ * is_last_write - determine if an offset was in the last write to a LEB.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to check
+ * @offs: offset to check
+ *
+ * This function returns %1 if @offs was in the last write to the LEB whose data
+ * is in @buf, otherwise %0 is returned. The determination is made by checking
+ * for subsequent empty space starting from the next min_io_size boundary (or a
+ * bit less than the common header size if min_io_size is one).
+ */
+static int is_last_write(const struct ubifs_info *c, void *buf, int offs)
+{
+ int empty_offs;
+ int check_len;
+ uint8_t *p;
+
+ if (c->min_io_size == 1) {
+ check_len = c->leb_size - offs;
+ p = buf + check_len;
+ for (; check_len > 0; check_len--)
+ if (*--p != 0xff)
+ break;
+ /*
+ * 'check_len' is the size of the corruption which cannot be
+ * more than the size of 1 node if it was caused by an unclean
+ * unmount.
+ */
+ if (check_len > UBIFS_MAX_NODE_SZ)
+ return 0;
+ return 1;
+ }
+
+ /*
+ * Round up to the next c->min_io_size boundary i.e. 'offs' is in the
+ * last wbuf written. After that should be empty space.
+ */
+ empty_offs = ALIGN(offs + 1, c->min_io_size);
+ check_len = c->leb_size - empty_offs;
+ p = buf + empty_offs - offs;
+
+ for (; check_len > 0; check_len--)
+ if (*p++ != 0xff)
+ return 0;
+ return 1;
+}
+
+/**
+ * clean_buf - clean the data from an LEB sitting in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to clean
+ * @lnum: LEB number to clean
+ * @offs: offset from which to clean
+ * @len: length of buffer
+ *
+ * This function pads up to the next min_io_size boundary (if there is one) and
+ * sets empty space to all 0xff. @buf, @offs and @len are updated to the next
+ * min_io_size boundary (if there is one).
+ */
+static void clean_buf(const struct ubifs_info *c, void **buf, int lnum,
+ int *offs, int *len)
+{
+ int empty_offs, pad_len;
+
+ lnum = lnum;
+ dbg_rcvry("cleaning corruption at %d:%d", lnum, *offs);
+
+ if (c->min_io_size == 1) {
+ memset(*buf, 0xff, c->leb_size - *offs);
+ return;
+ }
+
+ ubifs_assert(!(*offs & 7));
+ empty_offs = ALIGN(*offs, c->min_io_size);
+ pad_len = empty_offs - *offs;
+ ubifs_pad(c, *buf, pad_len);
+ *offs += pad_len;
+ *buf += pad_len;
+ *len -= pad_len;
+ memset(*buf, 0xff, c->leb_size - empty_offs);
+}
+
+/**
+ * no_more_nodes - determine if there are no more nodes in a buffer.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to check
+ * @len: length of buffer
+ * @lnum: LEB number of the LEB from which @buf was read
+ * @offs: offset from which @buf was read
+ *
+ * This function scans @buf for more nodes and returns %0 is a node is found and
+ * %1 if no more nodes are found.
+ */
+static int no_more_nodes(const struct ubifs_info *c, void *buf, int len,
+ int lnum, int offs)
+{
+ int skip, next_offs = 0;
+
+ if (len > UBIFS_DATA_NODE_SZ) {
+ struct ubifs_ch *ch = buf;
+ int dlen = le32_to_cpu(ch->len);
+
+ if (ch->node_type == UBIFS_DATA_NODE && dlen >= UBIFS_CH_SZ &&
+ dlen <= UBIFS_MAX_DATA_NODE_SZ)
+ /* The corrupt node looks like a data node */
+ next_offs = ALIGN(offs + dlen, 8);
+ }
+
+ if (c->min_io_size == 1)
+ skip = 8;
+ else
+ skip = ALIGN(offs + 1, c->min_io_size) - offs;
+
+ offs += skip;
+ buf += skip;
+ len -= skip;
+ while (len > 8) {
+ struct ubifs_ch *ch = buf;
+ uint32_t magic = le32_to_cpu(ch->magic);
+ int ret;
+
+ if (magic == UBIFS_NODE_MAGIC) {
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, 1);
+ if (ret == SCANNED_A_NODE || ret > 0) {
+ /*
+ * There is a small chance this is just data in
+ * a data node, so check that possibility. e.g.
+ * this is part of a file that itself contains
+ * a UBIFS image.
+ */
+ if (next_offs && offs + le32_to_cpu(ch->len) <=
+ next_offs)
+ continue;
+ dbg_rcvry("unexpected node at %d:%d", lnum,
+ offs);
+ return 0;
+ }
+ }
+ offs += 8;
+ buf += 8;
+ len -= 8;
+ }
+ return 1;
+}
+
+/**
+ * fix_unclean_leb - fix an unclean LEB.
+ * @c: UBIFS file-system description object
+ * @sleb: scanned LEB information
+ * @start: offset where scan started
+ */
+static int fix_unclean_leb(struct ubifs_info *c, struct ubifs_scan_leb *sleb,
+ int start)
+{
+ int lnum = sleb->lnum, endpt = start;
+
+ /* Get the end offset of the last node we are keeping */
+ if (!list_empty(&sleb->nodes)) {
+ struct ubifs_scan_node *snod;
+
+ snod = list_entry(sleb->nodes.prev,
+ struct ubifs_scan_node, list);
+ endpt = snod->offs + snod->len;
+ }
+
+ if ((c->vfs_sb->s_flags & MS_RDONLY) && !c->remounting_rw) {
+ /* Add to recovery list */
+ struct ubifs_unclean_leb *ucleb;
+
+ dbg_rcvry("need to fix LEB %d start %d endpt %d",
+ lnum, start, sleb->endpt);
+ ucleb = kzalloc(sizeof(struct ubifs_unclean_leb), GFP_NOFS);
+ if (!ucleb)
+ return -ENOMEM;
+ ucleb->lnum = lnum;
+ ucleb->endpt = endpt;
+ list_add_tail(&ucleb->list, &c->unclean_leb_list);
+ }
+ return 0;
+}
+
+/**
+ * drop_incomplete_group - drop nodes from an incomplete group.
+ * @sleb: scanned LEB information
+ * @offs: offset of dropped nodes is returned here
+ *
+ * This function returns %1 if nodes are dropped and %0 otherwise.
+ */
+static int drop_incomplete_group(struct ubifs_scan_leb *sleb, int *offs)
+{
+ int dropped = 0;
+
+ while (!list_empty(&sleb->nodes)) {
+ struct ubifs_scan_node *snod;
+ struct ubifs_ch *ch;
+
+ snod = list_entry(sleb->nodes.prev, struct ubifs_scan_node,
+ list);
+ ch = snod->node;
+ if (ch->group_type != UBIFS_IN_NODE_GROUP)
+ return dropped;
+ dbg_rcvry("dropping node at %d:%d", sleb->lnum, snod->offs);
+ *offs = snod->offs;
+ list_del(&snod->list);
+ kfree(snod);
+ sleb->nodes_cnt -= 1;
+ dropped = 1;
+ }
+ return dropped;
+}
+
+/**
+ * ubifs_recover_leb - scan and recover a LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @offs: offset
+ * @sbuf: LEB-sized buffer to use
+ * @grouped: nodes may be grouped for recovery
+ *
+ * This function does a scan of a LEB, but caters for errors that might have
+ * been caused by the unclean unmount from which we are attempting to recover.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_recover_leb(struct ubifs_info *c, int lnum,
+ int offs, void *sbuf, int grouped)
+{
+ int err, len = c->leb_size - offs, need_clean = 0, quiet = 1;
+ int empty_chkd = 0, start = offs;
+ struct ubifs_scan_leb *sleb;
+ void *buf = sbuf + offs;
+
+ dbg_rcvry("%d:%d", lnum, offs);
+
+ sleb = ubifs_start_scan(c, lnum, offs, sbuf);
+ if (IS_ERR(sleb))
+ return sleb;
+
+ if (sleb->ecc)
+ need_clean = 1;
+
+ while (len >= 8) {
+ int ret;
+
+ dbg_scan("look at LEB %d:%d (%d bytes left)",
+ lnum, offs, len);
+
+ cond_resched();
+
+ /*
+ * Scan quietly until there is an error from which we cannot
+ * recover
+ */
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
+
+ if (ret == SCANNED_A_NODE) {
+ /* A valid node, and not a padding node */
+ struct ubifs_ch *ch = buf;
+ int node_len;
+
+ err = ubifs_add_snod(c, sleb, buf, offs);
+ if (err)
+ goto error;
+ node_len = ALIGN(le32_to_cpu(ch->len), 8);
+ offs += node_len;
+ buf += node_len;
+ len -= node_len;
+ continue;
+ }
+
+ if (ret > 0) {
+ /* Padding bytes or a valid padding node */
+ offs += ret;
+ buf += ret;
+ len -= ret;
+ continue;
+ }
+
+ if (ret == SCANNED_EMPTY_SPACE) {
+ if (!is_empty(buf, len)) {
+ if (!is_last_write(c, buf, offs))
+ break;
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ }
+ empty_chkd = 1;
+ break;
+ }
+
+ if (ret == SCANNED_GARBAGE || ret == SCANNED_A_BAD_PAD_NODE)
+ if (is_last_write(c, buf, offs)) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ empty_chkd = 1;
+ break;
+ }
+
+ if (ret == SCANNED_A_CORRUPT_NODE)
+ if (no_more_nodes(c, buf, len, lnum, offs)) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ empty_chkd = 1;
+ break;
+ }
+
+ if (quiet) {
+ /* Redo the last scan but noisily */
+ quiet = 0;
+ continue;
+ }
+
+ switch (ret) {
+ case SCANNED_GARBAGE:
+ dbg_err("garbage");
+ goto corrupted;
+ case SCANNED_A_CORRUPT_NODE:
+ case SCANNED_A_BAD_PAD_NODE:
+ dbg_err("bad node");
+ goto corrupted;
+ default:
+ dbg_err("unknown");
+ goto corrupted;
+ }
+ }
+
+ if (!empty_chkd && !is_empty(buf, len)) {
+ if (is_last_write(c, buf, offs)) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ } else {
+ ubifs_err("corrupt empty space at LEB %d:%d",
+ lnum, offs);
+ goto corrupted;
+ }
+ }
+
+ /* Drop nodes from incomplete group */
+ if (grouped && drop_incomplete_group(sleb, &offs)) {
+ buf = sbuf + offs;
+ len = c->leb_size - offs;
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ }
+
+ if (offs % c->min_io_size) {
+ clean_buf(c, &buf, lnum, &offs, &len);
+ need_clean = 1;
+ }
+
+ ubifs_end_scan(c, sleb, lnum, offs);
+
+ if (need_clean) {
+ err = fix_unclean_leb(c, sleb, start);
+ if (err)
+ goto error;
+ }
+
+ return sleb;
+
+corrupted:
+ ubifs_scanned_corruption(c, lnum, offs, buf);
+ err = -EUCLEAN;
+error:
+ ubifs_err("LEB %d scanning failed", lnum);
+ ubifs_scan_destroy(sleb);
+ return ERR_PTR(err);
+}
+
+/**
+ * get_cs_sqnum - get commit start sequence number.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of commit start node
+ * @offs: offset of commit start node
+ * @cs_sqnum: commit start sequence number is returned here
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int get_cs_sqnum(struct ubifs_info *c, int lnum, int offs,
+ unsigned long long *cs_sqnum)
+{
+ struct ubifs_cs_node *cs_node = NULL;
+ int err, ret;
+
+ dbg_rcvry("at %d:%d", lnum, offs);
+ cs_node = kmalloc(UBIFS_CS_NODE_SZ, GFP_KERNEL);
+ if (!cs_node)
+ return -ENOMEM;
+ if (c->leb_size - offs < UBIFS_CS_NODE_SZ)
+ goto out_err;
+ err = ubi_read(c->ubi, lnum, (void *)cs_node, offs, UBIFS_CS_NODE_SZ);
+ if (err && err != -EBADMSG)
+ goto out_free;
+ ret = ubifs_scan_a_node(c, cs_node, UBIFS_CS_NODE_SZ, lnum, offs, 0);
+ if (ret != SCANNED_A_NODE) {
+ dbg_err("Not a valid node");
+ goto out_err;
+ }
+ if (cs_node->ch.node_type != UBIFS_CS_NODE) {
+ dbg_err("Node a CS node, type is %d", cs_node->ch.node_type);
+ goto out_err;
+ }
+ if (le64_to_cpu(cs_node->cmt_no) != c->cmt_no) {
+ dbg_err("CS node cmt_no %llu != current cmt_no %llu",
+ (unsigned long long)le64_to_cpu(cs_node->cmt_no),
+ c->cmt_no);
+ goto out_err;
+ }
+ *cs_sqnum = le64_to_cpu(cs_node->ch.sqnum);
+ dbg_rcvry("commit start sqnum %llu", *cs_sqnum);
+ kfree(cs_node);
+ return 0;
+
+out_err:
+ err = -EINVAL;
+out_free:
+ ubifs_err("failed to get CS sqnum");
+ kfree(cs_node);
+ return err;
+}
+
+/**
+ * ubifs_recover_log_leb - scan and recover a log LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number
+ * @offs: offset
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function does a scan of a LEB, but caters for errors that might have
+ * been caused by the unclean unmount from which we are attempting to recover.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+struct ubifs_scan_leb *ubifs_recover_log_leb(struct ubifs_info *c, int lnum,
+ int offs, void *sbuf)
+{
+ struct ubifs_scan_leb *sleb;
+ int next_lnum;
+
+ dbg_rcvry("LEB %d", lnum);
+ next_lnum = lnum + 1;
+ if (next_lnum >= UBIFS_LOG_LNUM + c->log_lebs)
+ next_lnum = UBIFS_LOG_LNUM;
+ if (next_lnum != c->ltail_lnum) {
+ /*
+ * We can only recover at the end of the log, so check that the
+ * next log LEB is empty or out of date.
+ */
+ sleb = ubifs_scan(c, next_lnum, 0, sbuf);
+ if (IS_ERR(sleb))
+ return sleb;
+ if (sleb->nodes_cnt) {
+ struct ubifs_scan_node *snod;
+ unsigned long long cs_sqnum = c->cs_sqnum;
+
+ snod = list_entry(sleb->nodes.next,
+ struct ubifs_scan_node, list);
+ if (cs_sqnum == 0) {
+ int err;
+
+ err = get_cs_sqnum(c, lnum, offs, &cs_sqnum);
+ if (err) {
+ ubifs_scan_destroy(sleb);
+ return ERR_PTR(err);
+ }
+ }
+ if (snod->sqnum > cs_sqnum) {
+ ubifs_err("unrecoverable log corruption "
+ "in LEB %d", lnum);
+ ubifs_scan_destroy(sleb);
+ return ERR_PTR(-EUCLEAN);
+ }
+ }
+ ubifs_scan_destroy(sleb);
+ }
+ return ubifs_recover_leb(c, lnum, offs, sbuf, 0);
+}
+
+/**
+ * recover_head - recover a head.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number of head to recover
+ * @offs: offset of head to recover
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function ensures that there is no data on the flash at a head location.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int recover_head(const struct ubifs_info *c, int lnum, int offs,
+ void *sbuf)
+{
+ int len, err, need_clean = 0;
+
+ if (c->min_io_size > 1)
+ len = c->min_io_size;
+ else
+ len = 512;
+ if (offs + len > c->leb_size)
+ len = c->leb_size - offs;
+
+ if (!len)
+ return 0;
+
+ /* Read at the head location and check it is empty flash */
+ err = ubi_read(c->ubi, lnum, sbuf, offs, len);
+ if (err)
+ need_clean = 1;
+ else {
+ uint8_t *p = sbuf;
+
+ while (len--)
+ if (*p++ != 0xff) {
+ need_clean = 1;
+ break;
+ }
+ }
+
+ if (need_clean) {
+ dbg_rcvry("cleaning head at %d:%d", lnum, offs);
+ if (offs == 0)
+ return ubifs_leb_unmap(c, lnum);
+ err = ubi_read(c->ubi, lnum, sbuf, 0, offs);
+ if (err)
+ return err;
+ return ubi_leb_change(c->ubi, lnum, sbuf, offs, UBI_UNKNOWN);
+ }
+
+ return 0;
+}
+
+/**
+ * ubifs_recover_inl_heads - recover index and LPT heads.
+ * @c: UBIFS file-system description object
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function ensures that there is no data on the flash at the index and
+ * LPT head locations.
+ *
+ * This deals with the recovery of a half-completed journal commit. UBIFS is
+ * careful never to overwrite the last version of the index or the LPT. Because
+ * the index and LPT are wandering trees, data from a half-completed commit will
+ * not be referenced anywhere in UBIFS. The data will be either in LEBs that are
+ * assumed to be empty and will be unmapped anyway before use, or in the index
+ * and LPT heads.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_inl_heads(const struct ubifs_info *c, void *sbuf)
+{
+ int err;
+
+ ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY) || c->remounting_rw);
+
+ dbg_rcvry("checking index head at %d:%d", c->ihead_lnum, c->ihead_offs);
+ err = recover_head(c, c->ihead_lnum, c->ihead_offs, sbuf);
+ if (err)
+ return err;
+
+ dbg_rcvry("checking LPT head at %d:%d", c->nhead_lnum, c->nhead_offs);
+ err = recover_head(c, c->nhead_lnum, c->nhead_offs, sbuf);
+ if (err)
+ return err;
+
+ return 0;
+}
+
+/**
+ * clean_an_unclean_leb - read and write a LEB to remove corruption.
+ * @c: UBIFS file-system description object
+ * @ucleb: unclean LEB information
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function reads a LEB up to a point pre-determined by the mount recovery,
+ * checks the nodes, and writes the result back to the flash, thereby cleaning
+ * off any following corruption, or non-fatal ECC errors.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int clean_an_unclean_leb(const struct ubifs_info *c,
+ struct ubifs_unclean_leb *ucleb, void *sbuf)
+{
+ int err, lnum = ucleb->lnum, offs = 0, len = ucleb->endpt, quiet = 1;
+ void *buf = sbuf;
+
+ dbg_rcvry("LEB %d len %d", lnum, len);
+
+ if (len == 0) {
+ /* Nothing to read, just unmap it */
+ err = ubifs_leb_unmap(c, lnum);
+ if (err)
+ return err;
+ return 0;
+ }
+
+ err = ubi_read(c->ubi, lnum, buf, offs, len);
+ if (err && err != -EBADMSG)
+ return err;
+
+ while (len >= 8) {
+ int ret;
+
+ cond_resched();
+
+ /* Scan quietly until there is an error */
+ ret = ubifs_scan_a_node(c, buf, len, lnum, offs, quiet);
+
+ if (ret == SCANNED_A_NODE) {
+ /* A valid node, and not a padding node */
+ struct ubifs_ch *ch = buf;
+ int node_len;
+
+ node_len = ALIGN(le32_to_cpu(ch->len), 8);
+ offs += node_len;
+ buf += node_len;
+ len -= node_len;
+ continue;
+ }
+
+ if (ret > 0) {
+ /* Padding bytes or a valid padding node */
+ offs += ret;
+ buf += ret;
+ len -= ret;
+ continue;
+ }
+
+ if (ret == SCANNED_EMPTY_SPACE) {
+ ubifs_err("unexpected empty space at %d:%d",
+ lnum, offs);
+ return -EUCLEAN;
+ }
+
+ if (quiet) {
+ /* Redo the last scan but noisily */
+ quiet = 0;
+ continue;
+ }
+
+ ubifs_scanned_corruption(c, lnum, offs, buf);
+ return -EUCLEAN;
+ }
+
+ /* Pad to min_io_size */
+ len = ALIGN(ucleb->endpt, c->min_io_size);
+ if (len > ucleb->endpt) {
+ int pad_len = len - ALIGN(ucleb->endpt, 8);
+
+ if (pad_len > 0) {
+ buf = c->sbuf + len - pad_len;
+ ubifs_pad(c, buf, pad_len);
+ }
+ }
+
+ /* Write back the LEB atomically */
+ err = ubi_leb_change(c->ubi, lnum, sbuf, len, UBI_UNKNOWN);
+ if (err)
+ return err;
+
+ dbg_rcvry("cleaned LEB %d", lnum);
+
+ return 0;
+}
+
+/**
+ * ubifs_clean_lebs - clean LEBs recovered during read-only mount.
+ * @c: UBIFS file-system description object
+ * @sbuf: LEB-sized buffer to use
+ *
+ * This function cleans a LEB identified during recovery that needs to be
+ * written but was not because UBIFS was mounted read-only. This happens when
+ * remounting to read-write mode.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_clean_lebs(const struct ubifs_info *c, void *sbuf)
+{
+ dbg_rcvry("recovery");
+ while (!list_empty(&c->unclean_leb_list)) {
+ struct ubifs_unclean_leb *ucleb;
+ int err;
+
+ ucleb = list_entry(c->unclean_leb_list.next,
+ struct ubifs_unclean_leb, list);
+ err = clean_an_unclean_leb(c, ucleb, sbuf);
+ if (err)
+ return err;
+ list_del(&ucleb->list);
+ kfree(ucleb);
+ }
+ return 0;
+}
+
+/**
+ * struct size_entry - inode size information for recovery.
+ * @rb: link in the RB-tree of sizes
+ * @inum: inode number
+ * @i_size: size on inode
+ * @d_size: maximum size based on data nodes
+ * @exists: indicates whether the inode exists
+ * @inode: inode if pinned in memory awaiting rw mode to fix it
+ */
+struct size_entry {
+ struct rb_node rb;
+ ino_t inum;
+ loff_t i_size;
+ loff_t d_size;
+ int exists;
+ struct inode *inode;
+};
+
+/**
+ * add_ino - add an entry to the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ * @i_size: size on inode
+ * @d_size: maximum size based on data nodes
+ * @exists: indicates whether the inode exists
+ */
+static int add_ino(struct ubifs_info *c, ino_t inum, loff_t i_size,
+ loff_t d_size, int exists)
+{
+ struct rb_node **p = &c->size_tree.rb_node, *parent = NULL;
+ struct size_entry *e;
+
+ while (*p) {
+ parent = *p;
+ e = rb_entry(parent, struct size_entry, rb);
+ if (inum < e->inum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+
+ e = kzalloc(sizeof(struct size_entry), GFP_KERNEL);
+ if (!e)
+ return -ENOMEM;
+
+ e->inum = inum;
+ e->i_size = i_size;
+ e->d_size = d_size;
+ e->exists = exists;
+
+ rb_link_node(&e->rb, parent, p);
+ rb_insert_color(&e->rb, &c->size_tree);
+
+ return 0;
+}
+
+/**
+ * find_ino - find an entry on the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ */
+static struct size_entry *find_ino(struct ubifs_info *c, ino_t inum)
+{
+ struct rb_node *p = c->size_tree.rb_node;
+ struct size_entry *e;
+
+ while (p) {
+ e = rb_entry(p, struct size_entry, rb);
+ if (inum < e->inum)
+ p = p->rb_left;
+ else if (inum > e->inum)
+ p = p->rb_right;
+ else
+ return e;
+ }
+ return NULL;
+}
+
+/**
+ * remove_ino - remove an entry from the size tree.
+ * @c: UBIFS file-system description object
+ * @inum: inode number
+ */
+static void remove_ino(struct ubifs_info *c, ino_t inum)
+{
+ struct size_entry *e = find_ino(c, inum);
+
+ if (!e)
+ return;
+ rb_erase(&e->rb, &c->size_tree);
+ kfree(e);
+}
+
+/**
+ * ubifs_recover_size_accum - accumulate inode sizes for recovery.
+ * @c: UBIFS file-system description object
+ * @key: node key
+ * @deletion: node is for a deletion
+ * @new_size: inode size
+ *
+ * This function has two purposes:
+ * 1) to ensure there are no data nodes that fall outside the inode size
+ * 2) to ensure there are no data nodes for inodes that do not exist
+ * To accomplish those purposes, a rb-tree is constructed containing an entry
+ * for each inode number in the journal that has not been deleted, and recording
+ * the size from the inode node, the maximum size of any data node (also altered
+ * by truncations) and a flag indicating a inode number for which no inode node
+ * was present in the journal.
+ *
+ * Note that there is still the possibility that there are data nodes that have
+ * been committed that are beyond the inode size, however the only way to find
+ * them would be to scan the entire index. Alternatively, some provision could
+ * be made to record the size of inodes at the start of commit, which would seem
+ * very cumbersome for a scenario that is quite unlikely and the only negative
+ * consequence of which is wasted space.
+ *
+ * This functions returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_size_accum(struct ubifs_info *c, union ubifs_key *key,
+ int deletion, loff_t new_size)
+{
+ ino_t inum = key_inum(c, key);
+ struct size_entry *e;
+ int err;
+
+ switch (key_type(c, key)) {
+ case UBIFS_INO_KEY:
+ if (deletion)
+ remove_ino(c, inum);
+ else {
+ e = find_ino(c, inum);
+ if (e) {
+ e->i_size = new_size;
+ e->exists = 1;
+ } else {
+ err = add_ino(c, inum, new_size, 0, 1);
+ if (err)
+ return err;
+ }
+ }
+ break;
+ case UBIFS_DATA_KEY:
+ e = find_ino(c, inum);
+ if (e) {
+ if (new_size > e->d_size)
+ e->d_size = new_size;
+ } else {
+ err = add_ino(c, inum, 0, new_size, 0);
+ if (err)
+ return err;
+ }
+ break;
+ case UBIFS_TRUN_KEY:
+ e = find_ino(c, inum);
+ if (e)
+ e->d_size = new_size;
+ break;
+ }
+ return 0;
+}
+
+/**
+ * ubifs_recover_size - recover inode size.
+ * @c: UBIFS file-system description object
+ *
+ * This function attempts to fix inode size discrepancies identified by the
+ * 'ubifs_recover_size_accum()' function.
+ *
+ * This functions returns %0 on success and a negative error code on failure.
+ */
+int ubifs_recover_size(struct ubifs_info *c)
+{
+ struct rb_node *this = rb_first(&c->size_tree);
+
+ while (this) {
+ struct size_entry *e;
+ int err;
+
+ e = rb_entry(this, struct size_entry, rb);
+ if (!e->exists) {
+ union ubifs_key key;
+
+ ino_key_init(c, &key, e->inum);
+ err = ubifs_tnc_lookup(c, &key, c->sbuf);
+ if (err && err != -ENOENT)
+ return err;
+ if (err == -ENOENT) {
+ /* Remove data nodes that have no inode */
+ dbg_rcvry("removing ino %lu",
+ (unsigned long)e->inum);
+ err = ubifs_tnc_remove_ino(c, e->inum);
+ if (err)
+ return err;
+ } else {
+ struct ubifs_ino_node *ino = c->sbuf;
+
+ e->exists = 1;
+ e->i_size = le64_to_cpu(ino->size);
+ }
+ }
+ if (e->exists && e->i_size < e->d_size) {
+ if (!e->inode && (c->vfs_sb->s_flags & MS_RDONLY)) {
+ /* Fix the inode size and pin it in memory */
+ struct inode *inode;
+
+ inode = ubifs_iget(c->vfs_sb, e->inum);
+ if (IS_ERR(inode))
+ return PTR_ERR(inode);
+ if (inode->i_size < e->d_size) {
+ dbg_rcvry("ino %lu size %lld -> %lld",
+ (unsigned long)e->inum,
+ e->d_size, inode->i_size);
+ inode->i_size = e->d_size;
+ ubifs_inode(inode)->ui_size = e->d_size;
+ e->inode = inode;
+ this = rb_next(this);
+ continue;
+ }
+ iput(inode);
+ }
+ }
+ this = rb_next(this);
+ rb_erase(&e->rb, &c->size_tree);
+ kfree(e);
+ }
+ return 0;
+}
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
new file mode 100644
index 0000000..da33a14
--- /dev/null
+++ b/fs/ubifs/replay.c
@@ -0,0 +1,1070 @@
+/*
+ * 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 Ðртём)
+ */
+
+/*
+ * 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)) {
+ /*
+ * The LEB was added to the journal with a starting offset of
+ * zero which means the LEB must have been empty. The LEB
+ * property values should be lp->free == c->leb_size and
+ * lp->dirty == 0, but that is not the case. The reason is that
+ * the LEB was garbage collected. The garbage collector resets
+ * the free and dirty space without recording it anywhere except
+ * lprops, so if there is not a commit then lprops does not have
+ * that information next time the file system is mounted.
+ *
+ * We do not need to adjust free space because the scan has told
+ * us the exact value which is recorded in the replay entry as
+ * r->free.
+ *
+ * However we do need to subtract from the dirty space the
+ * amount of space that the garbage collector reclaimed, which
+ * is the whole LEB minus the amount of space that was free.
+ */
+ 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 the replay order was perfect the dirty space would now be
+ * zero. The order is not perfect because the the journal heads
+ * race with each other. This is not a problem but is does mean
+ * that the dirty space may temporarily exceed c->leb_size
+ * during the replay.
+ */
+ 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_inum(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 deal with 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_inum(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 (is_hash_key(c, &r->key))
+ kfree((void *)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. The
+ * replay tree is an RB-tree containing @struct replay_entry elements which are
+ * indexed by the sequence number. The replay tree is applied at the very end
+ * of the replay process. Since the tree is sorted in sequence number order,
+ * the older modifications are applied first. This function 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_inum(c, key) >= c->highest_inum)
+ c->highest_inum = key_inum(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_inum(c, key) >= c->highest_inum)
+ c->highest_inum = key_inum(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;
+}
+
+/**
+ * ubifs_validate_entry - validate directory or extended attribute entry node.
+ * @c: UBIFS file-system description object
+ * @dent: the node to validate
+ *
+ * This function validates directory or extended attribute entry node @dent.
+ * Returns zero if the node is all right and a %-EINVAL if not.
+ */
+int ubifs_validate_entry(struct ubifs_info *c,
+ const struct ubifs_dent_node *dent)
+{
+ int key_type = key_type_flash(c, dent->key);
+ int nlen = le16_to_cpu(dent->nlen);
+
+ if (le32_to_cpu(dent->ch.len) != nlen + UBIFS_DENT_NODE_SZ + 1 ||
+ dent->type >= UBIFS_ITYPES_CNT ||
+ nlen > UBIFS_MAX_NLEN || dent->name[nlen] != 0 ||
+ strnlen((char *)dent->name, nlen) != nlen ||
+ le64_to_cpu(dent->inum) > MAX_INUM) {
+ ubifs_err("bad %s node", key_type == UBIFS_DENT_KEY ?
+ "directory entry" : "extended attribute entry");
+ return -EINVAL;
+ }
+
+ if (key_type != UBIFS_DENT_KEY && key_type != UBIFS_XENT_KEY) {
+ ubifs_err("bad key type %d", key_type);
+ return -EINVAL;
+ }
+
+ 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, (char *)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);
+ union ubifs_key key;
+
+ /* 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;
+ }
+
+ /*
+ * Create a fake truncation key just to use the same
+ * functions which expect nodes to have keys.
+ */
+ trun_key_init(c, &key, le32_to_cpu(trun->inum));
+ err = insert_node(c, lnum, snod->offs, snod->len,
+ &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);
+
+ *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 reference 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
+ *
+ * This function inserts a reference node to the replay tree and returns zero
+ * in case of success or a negative error code in case of failure.
+ */
+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;
+
+ dbg_mnt("add ref LEB %d:%d", lnum, offs);
+ 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 tree");
+ 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;
+
+ 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,
+ (unsigned long long)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 un-maps 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, LPROPS_NC, LPROPS_NC,
+ 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;
+
+ BUILD_BUG_ON(UBIFS_TRUN_KEY > 5);
+
+ /* 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,
+ (unsigned long)c->highest_inum);
+out:
+ destroy_replay_tree(c);
+ destroy_bud_list(c);
+ vfree(sbuf);
+ c->replaying = 0;
+ return err;
+}
--
1.6.1.3
More information about the U-Boot
mailing list