[U-Boot] [PATCH 2/8 v2] UBIFS: Implement read-only UBIFS support in U-Boot (Part 2)
Stefan Roese
sr at denx.de
Thu Mar 12 14:55:54 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/io.c | 316 ++++++++++++++
fs/ubifs/key.h | 557 +++++++++++++++++++++++++
fs/ubifs/log.c | 104 +++++
fs/ubifs/lprops.c | 842 +++++++++++++++++++++++++++++++++++++
fs/ubifs/lpt.c | 1105 +++++++++++++++++++++++++++++++++++++++++++++++++
fs/ubifs/lpt_commit.c | 171 ++++++++
6 files changed, 3095 insertions(+), 0 deletions(-)
create mode 100644 fs/ubifs/io.c
create mode 100644 fs/ubifs/key.h
create mode 100644 fs/ubifs/log.c
create mode 100644 fs/ubifs/lprops.c
create mode 100644 fs/ubifs/lpt.c
create mode 100644 fs/ubifs/lpt_commit.c
diff --git a/fs/ubifs/io.c b/fs/ubifs/io.c
new file mode 100644
index 0000000..aae5c65
--- /dev/null
+++ b/fs/ubifs/io.c
@@ -0,0 +1,316 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ * Copyright (C) 2006, 2007 University of Szeged, Hungary
+ *
+ * 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
+ * Zoltan Sogor
+ */
+
+/*
+ * This file implements UBIFS I/O subsystem which provides various I/O-related
+ * helper functions (reading/writing/checking/validating nodes) and implements
+ * write-buffering support. Write buffers help to save space which otherwise
+ * would have been wasted for padding to the nearest minimal I/O unit boundary.
+ * Instead, data first goes to the write-buffer and is flushed when the
+ * buffer is full or when it is not used for some time (by timer). This is
+ * similar to the mechanism is used by JFFS2.
+ *
+ * Write-buffers are defined by 'struct ubifs_wbuf' objects and protected by
+ * mutexes defined inside these objects. Since sometimes upper-level code
+ * has to lock the write-buffer (e.g. journal space reservation code), many
+ * functions related to write-buffers have "nolock" suffix which means that the
+ * caller has to lock the write-buffer before calling this function.
+ *
+ * UBIFS stores nodes at 64 bit-aligned addresses. If the node length is not
+ * aligned, UBIFS starts the next node from the aligned address, and the padded
+ * bytes may contain any rubbish. In other words, UBIFS does not put padding
+ * bytes in those small gaps. Common headers of nodes store real node lengths,
+ * not aligned lengths. Indexing nodes also store real lengths in branches.
+ *
+ * UBIFS uses padding when it pads to the next min. I/O unit. In this case it
+ * uses padding nodes or padding bytes, if the padding node does not fit.
+ *
+ * All UBIFS nodes are protected by CRC checksums and UBIFS checks all nodes
+ * every time they are read from the flash media.
+ */
+
+#include "ubifs.h"
+
+/**
+ * ubifs_ro_mode - switch UBIFS to read read-only mode.
+ * @c: UBIFS file-system description object
+ * @err: error code which is the reason of switching to R/O mode
+ */
+void ubifs_ro_mode(struct ubifs_info *c, int err)
+{
+ if (!c->ro_media) {
+ c->ro_media = 1;
+ c->no_chk_data_crc = 0;
+ ubifs_warn("switched to read-only mode, error %d", err);
+ dbg_dump_stack();
+ }
+}
+
+/**
+ * ubifs_check_node - check node.
+ * @c: UBIFS file-system description object
+ * @buf: node to check
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ * @quiet: print no messages
+ * @must_chk_crc: indicates whether to always check the CRC
+ *
+ * This function checks node magic number and CRC checksum. This function also
+ * validates node length to prevent UBIFS from becoming crazy when an attacker
+ * feeds it a file-system image with incorrect nodes. For example, too large
+ * node length in the common header could cause UBIFS to read memory outside of
+ * allocated buffer when checking the CRC checksum.
+ *
+ * This function may skip data nodes CRC checking if @c->no_chk_data_crc is
+ * true, which is controlled by corresponding UBIFS mount option. However, if
+ * @must_chk_crc is true, then @c->no_chk_data_crc is ignored and CRC is
+ * checked. Similarly, if @c->always_chk_crc is true, @c->no_chk_data_crc is
+ * ignored and CRC is checked.
+ *
+ * This function returns zero in case of success and %-EUCLEAN in case of bad
+ * CRC or magic.
+ */
+int ubifs_check_node(const struct ubifs_info *c, const void *buf, int lnum,
+ int offs, int quiet, int must_chk_crc)
+{
+ int err = -EINVAL, type, node_len;
+ uint32_t crc, node_crc, magic;
+ const struct ubifs_ch *ch = buf;
+
+ ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+ ubifs_assert(!(offs & 7) && offs < c->leb_size);
+
+ magic = le32_to_cpu(ch->magic);
+ if (magic != UBIFS_NODE_MAGIC) {
+ if (!quiet)
+ ubifs_err("bad magic %#08x, expected %#08x",
+ magic, UBIFS_NODE_MAGIC);
+ err = -EUCLEAN;
+ goto out;
+ }
+
+ type = ch->node_type;
+ if (type < 0 || type >= UBIFS_NODE_TYPES_CNT) {
+ if (!quiet)
+ ubifs_err("bad node type %d", type);
+ goto out;
+ }
+
+ node_len = le32_to_cpu(ch->len);
+ if (node_len + offs > c->leb_size)
+ goto out_len;
+
+ if (c->ranges[type].max_len == 0) {
+ if (node_len != c->ranges[type].len)
+ goto out_len;
+ } else if (node_len < c->ranges[type].min_len ||
+ node_len > c->ranges[type].max_len)
+ goto out_len;
+
+ if (!must_chk_crc && type == UBIFS_DATA_NODE && !c->always_chk_crc &&
+ c->no_chk_data_crc)
+ return 0;
+
+ crc = crc32(UBIFS_CRC32_INIT, buf + 8, node_len - 8);
+ node_crc = le32_to_cpu(ch->crc);
+ if (crc != node_crc) {
+ if (!quiet)
+ ubifs_err("bad CRC: calculated %#08x, read %#08x",
+ crc, node_crc);
+ err = -EUCLEAN;
+ goto out;
+ }
+
+ return 0;
+
+out_len:
+ if (!quiet)
+ ubifs_err("bad node length %d", node_len);
+out:
+ if (!quiet) {
+ ubifs_err("bad node at LEB %d:%d", lnum, offs);
+ dbg_dump_node(c, buf);
+ dbg_dump_stack();
+ }
+ return err;
+}
+
+/**
+ * ubifs_pad - pad flash space.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to put padding to
+ * @pad: how many bytes to pad
+ *
+ * The flash media obliges us to write only in chunks of %c->min_io_size and
+ * when we have to write less data we add padding node to the write-buffer and
+ * pad it to the next minimal I/O unit's boundary. Padding nodes help when the
+ * media is being scanned. If the amount of wasted space is not enough to fit a
+ * padding node which takes %UBIFS_PAD_NODE_SZ bytes, we write padding bytes
+ * pattern (%UBIFS_PADDING_BYTE).
+ *
+ * Padding nodes are also used to fill gaps when the "commit-in-gaps" method is
+ * used.
+ */
+void ubifs_pad(const struct ubifs_info *c, void *buf, int pad)
+{
+ uint32_t crc;
+
+ ubifs_assert(pad >= 0 && !(pad & 7));
+
+ if (pad >= UBIFS_PAD_NODE_SZ) {
+ struct ubifs_ch *ch = buf;
+ struct ubifs_pad_node *pad_node = buf;
+
+ ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+ ch->node_type = UBIFS_PAD_NODE;
+ ch->group_type = UBIFS_NO_NODE_GROUP;
+ ch->padding[0] = ch->padding[1] = 0;
+ ch->sqnum = 0;
+ ch->len = cpu_to_le32(UBIFS_PAD_NODE_SZ);
+ pad -= UBIFS_PAD_NODE_SZ;
+ pad_node->pad_len = cpu_to_le32(pad);
+ crc = crc32(UBIFS_CRC32_INIT, buf + 8, UBIFS_PAD_NODE_SZ - 8);
+ ch->crc = cpu_to_le32(crc);
+ memset(buf + UBIFS_PAD_NODE_SZ, 0, pad);
+ } else if (pad > 0)
+ /* Too little space, padding node won't fit */
+ memset(buf, UBIFS_PADDING_BYTE, pad);
+}
+
+/**
+ * next_sqnum - get next sequence number.
+ * @c: UBIFS file-system description object
+ */
+static unsigned long long next_sqnum(struct ubifs_info *c)
+{
+ unsigned long long sqnum;
+
+ spin_lock(&c->cnt_lock);
+ sqnum = ++c->max_sqnum;
+ spin_unlock(&c->cnt_lock);
+
+ if (unlikely(sqnum >= SQNUM_WARN_WATERMARK)) {
+ if (sqnum >= SQNUM_WATERMARK) {
+ ubifs_err("sequence number overflow %llu, end of life",
+ sqnum);
+ ubifs_ro_mode(c, -EINVAL);
+ }
+ ubifs_warn("running out of sequence numbers, end of life soon");
+ }
+
+ return sqnum;
+}
+
+/**
+ * ubifs_prepare_node - prepare node to be written to flash.
+ * @c: UBIFS file-system description object
+ * @node: the node to pad
+ * @len: node length
+ * @pad: if the buffer has to be padded
+ *
+ * This function prepares node at @node to be written to the media - it
+ * calculates node CRC, fills the common header, and adds proper padding up to
+ * the next minimum I/O unit if @pad is not zero.
+ */
+void ubifs_prepare_node(struct ubifs_info *c, void *node, int len, int pad)
+{
+ uint32_t crc;
+ struct ubifs_ch *ch = node;
+ unsigned long long sqnum = next_sqnum(c);
+
+ ubifs_assert(len >= UBIFS_CH_SZ);
+
+ ch->magic = cpu_to_le32(UBIFS_NODE_MAGIC);
+ ch->len = cpu_to_le32(len);
+ ch->group_type = UBIFS_NO_NODE_GROUP;
+ ch->sqnum = cpu_to_le64(sqnum);
+ ch->padding[0] = ch->padding[1] = 0;
+ crc = crc32(UBIFS_CRC32_INIT, node + 8, len - 8);
+ ch->crc = cpu_to_le32(crc);
+
+ if (pad) {
+ len = ALIGN(len, 8);
+ pad = ALIGN(len, c->min_io_size) - len;
+ ubifs_pad(c, node + len, pad);
+ }
+}
+
+/**
+ * ubifs_read_node - read node.
+ * @c: UBIFS file-system description object
+ * @buf: buffer to read to
+ * @type: node type
+ * @len: node length (not aligned)
+ * @lnum: logical eraseblock number
+ * @offs: offset within the logical eraseblock
+ *
+ * This function reads a node of known type and and length, checks it and
+ * stores in @buf. Returns zero in case of success, %-EUCLEAN if CRC mismatched
+ * and a negative error code in case of failure.
+ */
+int ubifs_read_node(const struct ubifs_info *c, void *buf, int type, int len,
+ int lnum, int offs)
+{
+ int err, l;
+ struct ubifs_ch *ch = buf;
+
+ dbg_io("LEB %d:%d, %s, length %d", lnum, offs, dbg_ntype(type), len);
+ ubifs_assert(lnum >= 0 && lnum < c->leb_cnt && offs >= 0);
+ ubifs_assert(len >= UBIFS_CH_SZ && offs + len <= c->leb_size);
+ ubifs_assert(!(offs & 7) && offs < c->leb_size);
+ ubifs_assert(type >= 0 && type < UBIFS_NODE_TYPES_CNT);
+
+ err = ubi_read(c->ubi, lnum, buf, offs, len);
+ if (err && err != -EBADMSG) {
+ ubifs_err("cannot read node %d from LEB %d:%d, error %d",
+ type, lnum, offs, err);
+ return err;
+ }
+
+ if (type != ch->node_type) {
+ ubifs_err("bad node type (%d but expected %d)",
+ ch->node_type, type);
+ goto out;
+ }
+
+ err = ubifs_check_node(c, buf, lnum, offs, 0, 0);
+ if (err) {
+ ubifs_err("expected node type %d", type);
+ return err;
+ }
+
+ l = le32_to_cpu(ch->len);
+ if (l != len) {
+ ubifs_err("bad node length %d, expected %d", l, len);
+ goto out;
+ }
+
+ return 0;
+
+out:
+ ubifs_err("bad node at LEB %d:%d", lnum, offs);
+ dbg_dump_node(c, buf);
+ dbg_dump_stack();
+ return -EINVAL;
+}
diff --git a/fs/ubifs/key.h b/fs/ubifs/key.h
new file mode 100644
index 0000000..efb3430
--- /dev/null
+++ b/fs/ubifs/key.h
@@ -0,0 +1,557 @@
+/*
+ * 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 header contains various key-related definitions and helper function.
+ * UBIFS allows several key schemes, so we access key fields only via these
+ * helpers. At the moment only one key scheme is supported.
+ *
+ * Simple key scheme
+ * ~~~~~~~~~~~~~~~~~
+ *
+ * Keys are 64-bits long. First 32-bits are inode number (parent inode number
+ * in case of direntry key). Next 3 bits are node type. The last 29 bits are
+ * 4KiB offset in case of inode node, and direntry hash in case of a direntry
+ * node. We use "r5" hash borrowed from reiserfs.
+ */
+
+#ifndef __UBIFS_KEY_H__
+#define __UBIFS_KEY_H__
+
+/**
+ * key_mask_hash - mask a valid hash value.
+ * @val: value to be masked
+ *
+ * We use hash values as offset in directories, so values %0 and %1 are
+ * reserved for "." and "..". %2 is reserved for "end of readdir" marker. This
+ * function makes sure the reserved values are not used.
+ */
+static inline uint32_t key_mask_hash(uint32_t hash)
+{
+ hash &= UBIFS_S_KEY_HASH_MASK;
+ if (unlikely(hash <= 2))
+ hash += 3;
+ return hash;
+}
+
+/**
+ * key_r5_hash - R5 hash function (borrowed from reiserfs).
+ * @s: direntry name
+ * @len: name length
+ */
+static inline uint32_t key_r5_hash(const char *s, int len)
+{
+ uint32_t a = 0;
+ const signed char *str = (const signed char *)s;
+
+ while (*str) {
+ a += *str << 4;
+ a += *str >> 4;
+ a *= 11;
+ str++;
+ }
+
+ return key_mask_hash(a);
+}
+
+/**
+ * key_test_hash - testing hash function.
+ * @str: direntry name
+ * @len: name length
+ */
+static inline uint32_t key_test_hash(const char *str, int len)
+{
+ uint32_t a = 0;
+
+ len = min_t(uint32_t, len, 4);
+ memcpy(&a, str, len);
+ return key_mask_hash(a);
+}
+
+/**
+ * ino_key_init - initialize inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void ino_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * ino_key_init_flash - initialize on-flash inode key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: inode number
+ */
+static inline void ino_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum)
+{
+ union ubifs_key *key = k;
+
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(UBIFS_INO_KEY << UBIFS_S_KEY_BLOCK_BITS);
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_ino_key - get the lowest possible inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void lowest_ino_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = 0;
+}
+
+/**
+ * highest_ino_key - get the highest possible inode key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ */
+static inline void highest_ino_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = 0xffffffff;
+}
+
+/**
+ * dent_key_init - initialize directory entry key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: parent inode number
+ * @nm: direntry name and length
+ */
+static inline void dent_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ const struct qstr *nm)
+{
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * dent_key_init_hash - initialize directory entry key without re-calculating
+ * hash function.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: parent inode number
+ * @hash: direntry name hash
+ */
+static inline void dent_key_init_hash(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ uint32_t hash)
+{
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * dent_key_init_flash - initialize on-flash directory entry key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: parent inode number
+ * @nm: direntry name and length
+ */
+static inline void dent_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum, const struct qstr *nm)
+{
+ union ubifs_key *key = k;
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(hash |
+ (UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS));
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_dent_key - get the lowest possible directory entry key.
+ * @c: UBIFS file-system description object
+ * @key: where to store the lowest key
+ * @inum: parent inode number
+ */
+static inline void lowest_dent_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_DENT_KEY << UBIFS_S_KEY_HASH_BITS;
+}
+
+/**
+ * xent_key_init - initialize extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: host inode number
+ * @nm: extended attribute entry name and length
+ */
+static inline void xent_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ const struct qstr *nm)
+{
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * xent_key_init_hash - initialize extended attribute entry key without
+ * re-calculating hash function.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: host inode number
+ * @hash: extended attribute entry name hash
+ */
+static inline void xent_key_init_hash(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ uint32_t hash)
+{
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = hash | (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS);
+}
+
+/**
+ * xent_key_init_flash - initialize on-flash extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: host inode number
+ * @nm: extended attribute entry name and length
+ */
+static inline void xent_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum, const struct qstr *nm)
+{
+ union ubifs_key *key = k;
+ uint32_t hash = c->key_hash(nm->name, nm->len);
+
+ ubifs_assert(!(hash & ~UBIFS_S_KEY_HASH_MASK));
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(hash |
+ (UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS));
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * lowest_xent_key - get the lowest possible extended attribute entry key.
+ * @c: UBIFS file-system description object
+ * @key: where to store the lowest key
+ * @inum: host inode number
+ */
+static inline void lowest_xent_key(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_XENT_KEY << UBIFS_S_KEY_HASH_BITS;
+}
+
+/**
+ * data_key_init - initialize data key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ * @block: block number
+ */
+static inline void data_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum,
+ unsigned int block)
+{
+ ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
+ key->u32[0] = inum;
+ key->u32[1] = block | (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS);
+}
+
+/**
+ * data_key_init_flash - initialize on-flash data key.
+ * @c: UBIFS file-system description object
+ * @k: key to initialize
+ * @inum: inode number
+ * @block: block number
+ */
+static inline void data_key_init_flash(const struct ubifs_info *c, void *k,
+ ino_t inum, unsigned int block)
+{
+ union ubifs_key *key = k;
+
+ ubifs_assert(!(block & ~UBIFS_S_KEY_BLOCK_MASK));
+ key->j32[0] = cpu_to_le32(inum);
+ key->j32[1] = cpu_to_le32(block |
+ (UBIFS_DATA_KEY << UBIFS_S_KEY_BLOCK_BITS));
+ memset(k + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * trun_key_init - initialize truncation node key.
+ * @c: UBIFS file-system description object
+ * @key: key to initialize
+ * @inum: inode number
+ *
+ * Note, UBIFS does not have truncation keys on the media and this function is
+ * only used for purposes of replay.
+ */
+static inline void trun_key_init(const struct ubifs_info *c,
+ union ubifs_key *key, ino_t inum)
+{
+ key->u32[0] = inum;
+ key->u32[1] = UBIFS_TRUN_KEY << UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_type - get key type.
+ * @c: UBIFS file-system description object
+ * @key: key to get type of
+ */
+static inline int key_type(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ return key->u32[1] >> UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_type_flash - get type of a on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: key to get type of
+ */
+static inline int key_type_flash(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
+}
+
+/**
+ * key_inum - fetch inode number from key.
+ * @c: UBIFS file-system description object
+ * @k: key to fetch inode number from
+ */
+static inline ino_t key_inum(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return key->u32[0];
+}
+
+/**
+ * key_inum_flash - fetch inode number from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: key to fetch inode number from
+ */
+static inline ino_t key_inum_flash(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->j32[0]);
+}
+
+/**
+ * key_hash - get directory entry hash.
+ * @c: UBIFS file-system description object
+ * @key: the key to get hash from
+ */
+static inline int key_hash(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ return key->u32[1] & UBIFS_S_KEY_HASH_MASK;
+}
+
+/**
+ * key_hash_flash - get directory entry hash from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: the key to get hash from
+ */
+static inline int key_hash_flash(const struct ubifs_info *c, const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_HASH_MASK;
+}
+
+/**
+ * key_block - get data block number.
+ * @c: UBIFS file-system description object
+ * @key: the key to get the block number from
+ */
+static inline unsigned int key_block(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ return key->u32[1] & UBIFS_S_KEY_BLOCK_MASK;
+}
+
+/**
+ * key_block_flash - get data block number from an on-flash formatted key.
+ * @c: UBIFS file-system description object
+ * @k: the key to get the block number from
+ */
+static inline unsigned int key_block_flash(const struct ubifs_info *c,
+ const void *k)
+{
+ const union ubifs_key *key = k;
+
+ return le32_to_cpu(key->j32[1]) & UBIFS_S_KEY_BLOCK_MASK;
+}
+
+/**
+ * key_read - transform a key to in-memory format.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_read(const struct ubifs_info *c, const void *from,
+ union ubifs_key *to)
+{
+ const union ubifs_key *f = from;
+
+ to->u32[0] = le32_to_cpu(f->j32[0]);
+ to->u32[1] = le32_to_cpu(f->j32[1]);
+}
+
+/**
+ * key_write - transform a key from in-memory format.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_write(const struct ubifs_info *c,
+ const union ubifs_key *from, void *to)
+{
+ union ubifs_key *t = to;
+
+ t->j32[0] = cpu_to_le32(from->u32[0]);
+ t->j32[1] = cpu_to_le32(from->u32[1]);
+ memset(to + 8, 0, UBIFS_MAX_KEY_LEN - 8);
+}
+
+/**
+ * key_write_idx - transform a key from in-memory format for the index.
+ * @c: UBIFS file-system description object
+ * @from: the key to transform
+ * @to: the key to store the result
+ */
+static inline void key_write_idx(const struct ubifs_info *c,
+ const union ubifs_key *from, void *to)
+{
+ union ubifs_key *t = to;
+
+ t->j32[0] = cpu_to_le32(from->u32[0]);
+ t->j32[1] = cpu_to_le32(from->u32[1]);
+}
+
+/**
+ * key_copy - copy a key.
+ * @c: UBIFS file-system description object
+ * @from: the key to copy from
+ * @to: the key to copy to
+ */
+static inline void key_copy(const struct ubifs_info *c,
+ const union ubifs_key *from, union ubifs_key *to)
+{
+ to->u64[0] = from->u64[0];
+}
+
+/**
+ * keys_cmp - compare keys.
+ * @c: UBIFS file-system description object
+ * @key1: the first key to compare
+ * @key2: the second key to compare
+ *
+ * This function compares 2 keys and returns %-1 if @key1 is less than
+ * @key2, %0 if the keys are equivalent and %1 if @key1 is greater than @key2.
+ */
+static inline int keys_cmp(const struct ubifs_info *c,
+ const union ubifs_key *key1,
+ const union ubifs_key *key2)
+{
+ if (key1->u32[0] < key2->u32[0])
+ return -1;
+ if (key1->u32[0] > key2->u32[0])
+ return 1;
+ if (key1->u32[1] < key2->u32[1])
+ return -1;
+ if (key1->u32[1] > key2->u32[1])
+ return 1;
+
+ return 0;
+}
+
+/**
+ * keys_eq - determine if keys are equivalent.
+ * @c: UBIFS file-system description object
+ * @key1: the first key to compare
+ * @key2: the second key to compare
+ *
+ * This function compares 2 keys and returns %1 if @key1 is equal to @key2 and
+ * %0 if not.
+ */
+static inline int keys_eq(const struct ubifs_info *c,
+ const union ubifs_key *key1,
+ const union ubifs_key *key2)
+{
+ if (key1->u32[0] != key2->u32[0])
+ return 0;
+ if (key1->u32[1] != key2->u32[1])
+ return 0;
+ return 1;
+}
+
+/**
+ * is_hash_key - is a key vulnerable to hash collisions.
+ * @c: UBIFS file-system description object
+ * @key: key
+ *
+ * This function returns %1 if @key is a hashed key or %0 otherwise.
+ */
+static inline int is_hash_key(const struct ubifs_info *c,
+ const union ubifs_key *key)
+{
+ int type = key_type(c, key);
+
+ return type == UBIFS_DENT_KEY || type == UBIFS_XENT_KEY;
+}
+
+/**
+ * key_max_inode_size - get maximum file size allowed by current key format.
+ * @c: UBIFS file-system description object
+ */
+static inline unsigned long long key_max_inode_size(const struct ubifs_info *c)
+{
+ switch (c->key_fmt) {
+ case UBIFS_SIMPLE_KEY_FMT:
+ return (1ULL << UBIFS_S_KEY_BLOCK_BITS) * UBIFS_BLOCK_SIZE;
+ default:
+ return 0;
+ }
+}
+#endif /* !__UBIFS_KEY_H__ */
diff --git a/fs/ubifs/log.c b/fs/ubifs/log.c
new file mode 100644
index 0000000..68a9bd9
--- /dev/null
+++ b/fs/ubifs/log.c
@@ -0,0 +1,104 @@
+/*
+ * This file is part of UBIFS.
+ *
+ * Copyright (C) 2006-2008 Nokia Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors: Artem Bityutskiy (Битюцкий Ðртём)
+ * Adrian Hunter
+ */
+
+/*
+ * This file is a part of UBIFS journal implementation and contains various
+ * functions which manipulate the log. The log is a fixed area on the flash
+ * which does not contain any data but refers to buds. The log is a part of the
+ * journal.
+ */
+
+#include "ubifs.h"
+
+/**
+ * ubifs_search_bud - search bud LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: logical eraseblock number to search
+ *
+ * This function searches bud LEB @lnum. Returns bud description object in case
+ * of success and %NULL if there is no bud with this LEB number.
+ */
+struct ubifs_bud *ubifs_search_bud(struct ubifs_info *c, int lnum)
+{
+ struct rb_node *p;
+ struct ubifs_bud *bud;
+
+ spin_lock(&c->buds_lock);
+ p = c->buds.rb_node;
+ while (p) {
+ bud = rb_entry(p, struct ubifs_bud, rb);
+ if (lnum < bud->lnum)
+ p = p->rb_left;
+ else if (lnum > bud->lnum)
+ p = p->rb_right;
+ else {
+ spin_unlock(&c->buds_lock);
+ return bud;
+ }
+ }
+ spin_unlock(&c->buds_lock);
+ return NULL;
+}
+
+/**
+ * ubifs_add_bud - add bud LEB to the tree of buds and its journal head list.
+ * @c: UBIFS file-system description object
+ * @bud: the bud to add
+ */
+void ubifs_add_bud(struct ubifs_info *c, struct ubifs_bud *bud)
+{
+ struct rb_node **p, *parent = NULL;
+ struct ubifs_bud *b;
+ struct ubifs_jhead *jhead;
+
+ spin_lock(&c->buds_lock);
+ p = &c->buds.rb_node;
+ while (*p) {
+ parent = *p;
+ b = rb_entry(parent, struct ubifs_bud, rb);
+ ubifs_assert(bud->lnum != b->lnum);
+ if (bud->lnum < b->lnum)
+ p = &(*p)->rb_left;
+ else
+ p = &(*p)->rb_right;
+ }
+
+ rb_link_node(&bud->rb, parent, p);
+ rb_insert_color(&bud->rb, &c->buds);
+ if (c->jheads) {
+ jhead = &c->jheads[bud->jhead];
+ list_add_tail(&bud->list, &jhead->buds_list);
+ } else
+ ubifs_assert(c->replaying && (c->vfs_sb->s_flags & MS_RDONLY));
+
+ /*
+ * Note, although this is a new bud, we anyway account this space now,
+ * before any data has been written to it, because this is about to
+ * guarantee fixed mount time, and this bud will anyway be read and
+ * scanned.
+ */
+ c->bud_bytes += c->leb_size - bud->start;
+
+ dbg_log("LEB %d:%d, jhead %d, bud_bytes %lld", bud->lnum,
+ bud->start, bud->jhead, c->bud_bytes);
+ spin_unlock(&c->buds_lock);
+}
diff --git a/fs/ubifs/lprops.c b/fs/ubifs/lprops.c
new file mode 100644
index 0000000..8ce4949
--- /dev/null
+++ b/fs/ubifs/lprops.c
@@ -0,0 +1,842 @@
+/*
+ * 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 the functions that access LEB properties and their
+ * categories. LEBs are categorized based on the needs of UBIFS, and the
+ * categories are stored as either heaps or lists to provide a fast way of
+ * finding a LEB in a particular category. For example, UBIFS may need to find
+ * an empty LEB for the journal, or a very dirty LEB for garbage collection.
+ */
+
+#include "ubifs.h"
+
+/**
+ * get_heap_comp_val - get the LEB properties value for heap comparisons.
+ * @lprops: LEB properties
+ * @cat: LEB category
+ */
+static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
+{
+ switch (cat) {
+ case LPROPS_FREE:
+ return lprops->free;
+ case LPROPS_DIRTY_IDX:
+ return lprops->free + lprops->dirty;
+ default:
+ return lprops->dirty;
+ }
+}
+
+/**
+ * move_up_lpt_heap - move a new heap entry up as far as possible.
+ * @c: UBIFS file-system description object
+ * @heap: LEB category heap
+ * @lprops: LEB properties to move
+ * @cat: LEB category
+ *
+ * New entries to a heap are added at the bottom and then moved up until the
+ * parent's value is greater. In the case of LPT's category heaps, the value
+ * is either the amount of free space or the amount of dirty space, depending
+ * on the category.
+ */
+static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
+ struct ubifs_lprops *lprops, int cat)
+{
+ int val1, val2, hpos;
+
+ hpos = lprops->hpos;
+ if (!hpos)
+ return; /* Already top of the heap */
+ val1 = get_heap_comp_val(lprops, cat);
+ /* Compare to parent and, if greater, move up the heap */
+ do {
+ int ppos = (hpos - 1) / 2;
+
+ val2 = get_heap_comp_val(heap->arr[ppos], cat);
+ if (val2 >= val1)
+ return;
+ /* Greater than parent so move up */
+ heap->arr[ppos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[ppos];
+ heap->arr[ppos] = lprops;
+ lprops->hpos = ppos;
+ hpos = ppos;
+ } while (hpos);
+}
+
+/**
+ * adjust_lpt_heap - move a changed heap entry up or down the heap.
+ * @c: UBIFS file-system description object
+ * @heap: LEB category heap
+ * @lprops: LEB properties to move
+ * @hpos: heap position of @lprops
+ * @cat: LEB category
+ *
+ * Changed entries in a heap are moved up or down until the parent's value is
+ * greater. In the case of LPT's category heaps, the value is either the amount
+ * of free space or the amount of dirty space, depending on the category.
+ */
+static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
+ struct ubifs_lprops *lprops, int hpos, int cat)
+{
+ int val1, val2, val3, cpos;
+
+ val1 = get_heap_comp_val(lprops, cat);
+ /* Compare to parent and, if greater than parent, move up the heap */
+ if (hpos) {
+ int ppos = (hpos - 1) / 2;
+
+ val2 = get_heap_comp_val(heap->arr[ppos], cat);
+ if (val1 > val2) {
+ /* Greater than parent so move up */
+ while (1) {
+ heap->arr[ppos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[ppos];
+ heap->arr[ppos] = lprops;
+ lprops->hpos = ppos;
+ hpos = ppos;
+ if (!hpos)
+ return;
+ ppos = (hpos - 1) / 2;
+ val2 = get_heap_comp_val(heap->arr[ppos], cat);
+ if (val1 <= val2)
+ return;
+ /* Still greater than parent so keep going */
+ }
+ }
+ }
+
+ /* Not greater than parent, so compare to children */
+ while (1) {
+ /* Compare to left child */
+ cpos = hpos * 2 + 1;
+ if (cpos >= heap->cnt)
+ return;
+ val2 = get_heap_comp_val(heap->arr[cpos], cat);
+ if (val1 < val2) {
+ /* Less than left child, so promote biggest child */
+ if (cpos + 1 < heap->cnt) {
+ val3 = get_heap_comp_val(heap->arr[cpos + 1],
+ cat);
+ if (val3 > val2)
+ cpos += 1; /* Right child is bigger */
+ }
+ heap->arr[cpos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[cpos];
+ heap->arr[cpos] = lprops;
+ lprops->hpos = cpos;
+ hpos = cpos;
+ continue;
+ }
+ /* Compare to right child */
+ cpos += 1;
+ if (cpos >= heap->cnt)
+ return;
+ val3 = get_heap_comp_val(heap->arr[cpos], cat);
+ if (val1 < val3) {
+ /* Less than right child, so promote right child */
+ heap->arr[cpos]->hpos = hpos;
+ heap->arr[hpos] = heap->arr[cpos];
+ heap->arr[cpos] = lprops;
+ lprops->hpos = cpos;
+ hpos = cpos;
+ continue;
+ }
+ return;
+ }
+}
+
+/**
+ * add_to_lpt_heap - add LEB properties to a LEB category heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to add
+ * @cat: LEB category
+ *
+ * This function returns %1 if @lprops is added to the heap for LEB category
+ * @cat, otherwise %0 is returned because the heap is full.
+ */
+static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
+ int cat)
+{
+ struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
+
+ if (heap->cnt >= heap->max_cnt) {
+ const int b = LPT_HEAP_SZ / 2 - 1;
+ int cpos, val1, val2;
+
+ /* Compare to some other LEB on the bottom of heap */
+ /* Pick a position kind of randomly */
+ cpos = (((size_t)lprops >> 4) & b) + b;
+ ubifs_assert(cpos >= b);
+ ubifs_assert(cpos < LPT_HEAP_SZ);
+ ubifs_assert(cpos < heap->cnt);
+
+ val1 = get_heap_comp_val(lprops, cat);
+ val2 = get_heap_comp_val(heap->arr[cpos], cat);
+ if (val1 > val2) {
+ struct ubifs_lprops *lp;
+
+ lp = heap->arr[cpos];
+ lp->flags &= ~LPROPS_CAT_MASK;
+ lp->flags |= LPROPS_UNCAT;
+ list_add(&lp->list, &c->uncat_list);
+ lprops->hpos = cpos;
+ heap->arr[cpos] = lprops;
+ move_up_lpt_heap(c, heap, lprops, cat);
+ dbg_check_heap(c, heap, cat, lprops->hpos);
+ return 1; /* Added to heap */
+ }
+ dbg_check_heap(c, heap, cat, -1);
+ return 0; /* Not added to heap */
+ } else {
+ lprops->hpos = heap->cnt++;
+ heap->arr[lprops->hpos] = lprops;
+ move_up_lpt_heap(c, heap, lprops, cat);
+ dbg_check_heap(c, heap, cat, lprops->hpos);
+ return 1; /* Added to heap */
+ }
+}
+
+/**
+ * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to remove
+ * @cat: LEB category
+ */
+static void remove_from_lpt_heap(struct ubifs_info *c,
+ struct ubifs_lprops *lprops, int cat)
+{
+ struct ubifs_lpt_heap *heap;
+ int hpos = lprops->hpos;
+
+ heap = &c->lpt_heap[cat - 1];
+ ubifs_assert(hpos >= 0 && hpos < heap->cnt);
+ ubifs_assert(heap->arr[hpos] == lprops);
+ heap->cnt -= 1;
+ if (hpos < heap->cnt) {
+ heap->arr[hpos] = heap->arr[heap->cnt];
+ heap->arr[hpos]->hpos = hpos;
+ adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
+ }
+ dbg_check_heap(c, heap, cat, -1);
+}
+
+/**
+ * lpt_heap_replace - replace lprops in a category heap.
+ * @c: UBIFS file-system description object
+ * @old_lprops: LEB properties to replace
+ * @new_lprops: LEB properties with which to replace
+ * @cat: LEB category
+ *
+ * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
+ * and the lprops that the pnode contains. When that happens, references in
+ * the category heaps to those lprops must be updated to point to the new
+ * lprops. This function does that.
+ */
+static void lpt_heap_replace(struct ubifs_info *c,
+ struct ubifs_lprops *old_lprops,
+ struct ubifs_lprops *new_lprops, int cat)
+{
+ struct ubifs_lpt_heap *heap;
+ int hpos = new_lprops->hpos;
+
+ heap = &c->lpt_heap[cat - 1];
+ heap->arr[hpos] = new_lprops;
+}
+
+/**
+ * ubifs_add_to_cat - add LEB properties to a category list or heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to add
+ * @cat: LEB category to which to add
+ *
+ * LEB properties are categorized to enable fast find operations.
+ */
+void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
+ int cat)
+{
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ if (add_to_lpt_heap(c, lprops, cat))
+ break;
+ /* No more room on heap so make it uncategorized */
+ cat = LPROPS_UNCAT;
+ /* Fall through */
+ case LPROPS_UNCAT:
+ list_add(&lprops->list, &c->uncat_list);
+ break;
+ case LPROPS_EMPTY:
+ list_add(&lprops->list, &c->empty_list);
+ break;
+ case LPROPS_FREEABLE:
+ list_add(&lprops->list, &c->freeable_list);
+ c->freeable_cnt += 1;
+ break;
+ case LPROPS_FRDI_IDX:
+ list_add(&lprops->list, &c->frdi_idx_list);
+ break;
+ default:
+ ubifs_assert(0);
+ }
+ lprops->flags &= ~LPROPS_CAT_MASK;
+ lprops->flags |= cat;
+}
+
+/**
+ * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to remove
+ * @cat: LEB category from which to remove
+ *
+ * LEB properties are categorized to enable fast find operations.
+ */
+static void ubifs_remove_from_cat(struct ubifs_info *c,
+ struct ubifs_lprops *lprops, int cat)
+{
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ remove_from_lpt_heap(c, lprops, cat);
+ break;
+ case LPROPS_FREEABLE:
+ c->freeable_cnt -= 1;
+ ubifs_assert(c->freeable_cnt >= 0);
+ /* Fall through */
+ case LPROPS_UNCAT:
+ case LPROPS_EMPTY:
+ case LPROPS_FRDI_IDX:
+ ubifs_assert(!list_empty(&lprops->list));
+ list_del(&lprops->list);
+ break;
+ default:
+ ubifs_assert(0);
+ }
+}
+
+/**
+ * ubifs_replace_cat - replace lprops in a category list or heap.
+ * @c: UBIFS file-system description object
+ * @old_lprops: LEB properties to replace
+ * @new_lprops: LEB properties with which to replace
+ *
+ * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
+ * and the lprops that the pnode contains. When that happens, references in
+ * category lists and heaps must be replaced. This function does that.
+ */
+void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
+ struct ubifs_lprops *new_lprops)
+{
+ int cat;
+
+ cat = new_lprops->flags & LPROPS_CAT_MASK;
+ switch (cat) {
+ case LPROPS_DIRTY:
+ case LPROPS_DIRTY_IDX:
+ case LPROPS_FREE:
+ lpt_heap_replace(c, old_lprops, new_lprops, cat);
+ break;
+ case LPROPS_UNCAT:
+ case LPROPS_EMPTY:
+ case LPROPS_FREEABLE:
+ case LPROPS_FRDI_IDX:
+ list_replace(&old_lprops->list, &new_lprops->list);
+ break;
+ default:
+ ubifs_assert(0);
+ }
+}
+
+/**
+ * ubifs_ensure_cat - ensure LEB properties are categorized.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties
+ *
+ * A LEB may have fallen off of the bottom of a heap, and ended up as
+ * uncategorized even though it has enough space for us now. If that is the case
+ * this function will put the LEB back onto a heap.
+ */
+void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+ int cat = lprops->flags & LPROPS_CAT_MASK;
+
+ if (cat != LPROPS_UNCAT)
+ return;
+ cat = ubifs_categorize_lprops(c, lprops);
+ if (cat == LPROPS_UNCAT)
+ return;
+ ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
+ ubifs_add_to_cat(c, lprops, cat);
+}
+
+/**
+ * ubifs_categorize_lprops - categorize LEB properties.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to categorize
+ *
+ * LEB properties are categorized to enable fast find operations. This function
+ * returns the LEB category to which the LEB properties belong. Note however
+ * that if the LEB category is stored as a heap and the heap is full, the
+ * LEB properties may have their category changed to %LPROPS_UNCAT.
+ */
+int ubifs_categorize_lprops(const struct ubifs_info *c,
+ const struct ubifs_lprops *lprops)
+{
+ if (lprops->flags & LPROPS_TAKEN)
+ return LPROPS_UNCAT;
+
+ if (lprops->free == c->leb_size) {
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ return LPROPS_EMPTY;
+ }
+
+ if (lprops->free + lprops->dirty == c->leb_size) {
+ if (lprops->flags & LPROPS_INDEX)
+ return LPROPS_FRDI_IDX;
+ else
+ return LPROPS_FREEABLE;
+ }
+
+ if (lprops->flags & LPROPS_INDEX) {
+ if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
+ return LPROPS_DIRTY_IDX;
+ } else {
+ if (lprops->dirty >= c->dead_wm &&
+ lprops->dirty > lprops->free)
+ return LPROPS_DIRTY;
+ if (lprops->free > 0)
+ return LPROPS_FREE;
+ }
+
+ return LPROPS_UNCAT;
+}
+
+/**
+ * change_category - change LEB properties category.
+ * @c: UBIFS file-system description object
+ * @lprops: LEB properties to recategorize
+ *
+ * LEB properties are categorized to enable fast find operations. When the LEB
+ * properties change they must be recategorized.
+ */
+static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+ int old_cat = lprops->flags & LPROPS_CAT_MASK;
+ int new_cat = ubifs_categorize_lprops(c, lprops);
+
+ if (old_cat == new_cat) {
+ struct ubifs_lpt_heap *heap = &c->lpt_heap[new_cat - 1];
+
+ /* lprops on a heap now must be moved up or down */
+ if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
+ return; /* Not on a heap */
+ heap = &c->lpt_heap[new_cat - 1];
+ adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
+ } else {
+ ubifs_remove_from_cat(c, lprops, old_cat);
+ ubifs_add_to_cat(c, lprops, new_cat);
+ }
+}
+
+/**
+ * calc_dark - calculate LEB dark space size.
+ * @c: the UBIFS file-system description object
+ * @spc: amount of free and dirty space in the LEB
+ *
+ * This function calculates amount of dark space in an LEB which has @spc bytes
+ * of free and dirty space. Returns the calculations result.
+ *
+ * Dark space is the space which is not always usable - it depends on which
+ * nodes are written in which order. E.g., if an LEB has only 512 free bytes,
+ * it is dark space, because it cannot fit a large data node. So UBIFS cannot
+ * count on this LEB and treat these 512 bytes as usable because it is not true
+ * if, for example, only big chunks of uncompressible data will be written to
+ * the FS.
+ */
+static int calc_dark(struct ubifs_info *c, int spc)
+{
+ ubifs_assert(!(spc & 7));
+
+ if (spc < c->dark_wm)
+ return spc;
+
+ /*
+ * If we have slightly more space then the dark space watermark, we can
+ * anyway safely assume it we'll be able to write a node of the
+ * smallest size there.
+ */
+ if (spc - c->dark_wm < MIN_WRITE_SZ)
+ return spc - MIN_WRITE_SZ;
+
+ return c->dark_wm;
+}
+
+/**
+ * is_lprops_dirty - determine if LEB properties are dirty.
+ * @c: the UBIFS file-system description object
+ * @lprops: LEB properties to test
+ */
+static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
+{
+ struct ubifs_pnode *pnode;
+ int pos;
+
+ pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
+ pnode = (struct ubifs_pnode *)container_of(lprops - pos,
+ struct ubifs_pnode,
+ lprops[0]);
+ return !test_bit(COW_ZNODE, &pnode->flags) &&
+ test_bit(DIRTY_CNODE, &pnode->flags);
+}
+
+/**
+ * ubifs_change_lp - change LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lp: LEB properties to change
+ * @free: new free space amount
+ * @dirty: new dirty space amount
+ * @flags: new flags
+ * @idx_gc_cnt: change to the count of idx_gc list
+ *
+ * This function changes LEB properties (@free, @dirty or @flag). However, the
+ * property which has the %LPROPS_NC value is not changed. Returns a pointer to
+ * the updated LEB properties on success and a negative error code on failure.
+ *
+ * Note, the LEB properties may have had to be copied (due to COW) and
+ * consequently the pointer returned may not be the same as the pointer
+ * passed.
+ */
+const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
+ const struct ubifs_lprops *lp,
+ int free, int dirty, int flags,
+ int idx_gc_cnt)
+{
+ /*
+ * This is the only function that is allowed to change lprops, so we
+ * discard the const qualifier.
+ */
+ struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
+
+ dbg_lp("LEB %d, free %d, dirty %d, flags %d",
+ lprops->lnum, free, dirty, flags);
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+ ubifs_assert(c->lst.empty_lebs >= 0 &&
+ c->lst.empty_lebs <= c->main_lebs);
+ ubifs_assert(c->freeable_cnt >= 0);
+ ubifs_assert(c->freeable_cnt <= c->main_lebs);
+ ubifs_assert(c->lst.taken_empty_lebs >= 0);
+ ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
+ ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
+ ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
+ ubifs_assert(!(c->lst.total_used & 7));
+ ubifs_assert(free == LPROPS_NC || free >= 0);
+ ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
+
+ if (!is_lprops_dirty(c, lprops)) {
+ lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
+ if (IS_ERR(lprops))
+ return lprops;
+ } else
+ ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
+
+ ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
+
+ spin_lock(&c->space_lock);
+ if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
+ c->lst.taken_empty_lebs -= 1;
+
+ if (!(lprops->flags & LPROPS_INDEX)) {
+ int old_spc;
+
+ old_spc = lprops->free + lprops->dirty;
+ if (old_spc < c->dead_wm)
+ c->lst.total_dead -= old_spc;
+ else
+ c->lst.total_dark -= calc_dark(c, old_spc);
+
+ c->lst.total_used -= c->leb_size - old_spc;
+ }
+
+ if (free != LPROPS_NC) {
+ free = ALIGN(free, 8);
+ c->lst.total_free += free - lprops->free;
+
+ /* Increase or decrease empty LEBs counter if needed */
+ if (free == c->leb_size) {
+ if (lprops->free != c->leb_size)
+ c->lst.empty_lebs += 1;
+ } else if (lprops->free == c->leb_size)
+ c->lst.empty_lebs -= 1;
+ lprops->free = free;
+ }
+
+ if (dirty != LPROPS_NC) {
+ dirty = ALIGN(dirty, 8);
+ c->lst.total_dirty += dirty - lprops->dirty;
+ lprops->dirty = dirty;
+ }
+
+ if (flags != LPROPS_NC) {
+ /* Take care about indexing LEBs counter if needed */
+ if ((lprops->flags & LPROPS_INDEX)) {
+ if (!(flags & LPROPS_INDEX))
+ c->lst.idx_lebs -= 1;
+ } else if (flags & LPROPS_INDEX)
+ c->lst.idx_lebs += 1;
+ lprops->flags = flags;
+ }
+
+ if (!(lprops->flags & LPROPS_INDEX)) {
+ int new_spc;
+
+ new_spc = lprops->free + lprops->dirty;
+ if (new_spc < c->dead_wm)
+ c->lst.total_dead += new_spc;
+ else
+ c->lst.total_dark += calc_dark(c, new_spc);
+
+ c->lst.total_used += c->leb_size - new_spc;
+ }
+
+ if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
+ c->lst.taken_empty_lebs += 1;
+
+ change_category(c, lprops);
+ c->idx_gc_cnt += idx_gc_cnt;
+ spin_unlock(&c->space_lock);
+ return lprops;
+}
+
+/**
+ * ubifs_get_lp_stats - get lprops statistics.
+ * @c: UBIFS file-system description object
+ * @st: return statistics
+ */
+void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
+{
+ spin_lock(&c->space_lock);
+ memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
+ spin_unlock(&c->space_lock);
+}
+
+/**
+ * ubifs_change_one_lp - change LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to change properties for
+ * @free: amount of free space
+ * @dirty: amount of dirty space
+ * @flags_set: flags to set
+ * @flags_clean: flags to clean
+ * @idx_gc_cnt: change to the count of idx_gc list
+ *
+ * This function changes properties of LEB @lnum. It is a helper wrapper over
+ * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
+ * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
+ * a negative error code in case of failure.
+ */
+int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+ int flags_set, int flags_clean, int idx_gc_cnt)
+{
+ int err = 0, flags;
+ const struct ubifs_lprops *lp;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ flags = (lp->flags | flags_set) & ~flags_clean;
+ lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
+ if (IS_ERR(lp))
+ err = PTR_ERR(lp);
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_update_one_lp - update LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to change properties for
+ * @free: amount of free space
+ * @dirty: amount of dirty space to add
+ * @flags_set: flags to set
+ * @flags_clean: flags to clean
+ *
+ * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
+ * current dirty space, not substitutes it.
+ */
+int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
+ int flags_set, int flags_clean)
+{
+ int err = 0, flags;
+ const struct ubifs_lprops *lp;
+
+ ubifs_get_lprops(c);
+
+ lp = ubifs_lpt_lookup_dirty(c, lnum);
+ if (IS_ERR(lp)) {
+ err = PTR_ERR(lp);
+ goto out;
+ }
+
+ flags = (lp->flags | flags_set) & ~flags_clean;
+ lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
+ if (IS_ERR(lp))
+ err = PTR_ERR(lp);
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_read_one_lp - read LEB properties.
+ * @c: the UBIFS file-system description object
+ * @lnum: LEB to read properties for
+ * @lp: where to store read properties
+ *
+ * This helper function reads properties of a LEB @lnum and stores them in @lp.
+ * Returns zero in case of success and a negative error code in case of
+ * failure.
+ */
+int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
+{
+ int err = 0;
+ const struct ubifs_lprops *lpp;
+
+ ubifs_get_lprops(c);
+
+ lpp = ubifs_lpt_lookup(c, lnum);
+ if (IS_ERR(lpp)) {
+ err = PTR_ERR(lpp);
+ goto out;
+ }
+
+ memcpy(lp, lpp, sizeof(struct ubifs_lprops));
+
+out:
+ ubifs_release_lprops(c);
+ return err;
+}
+
+/**
+ * ubifs_fast_find_free - try to find a LEB with free space quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a LEB with free space or %NULL if
+ * the function is unable to find a LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+ struct ubifs_lpt_heap *heap;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ heap = &c->lpt_heap[LPROPS_FREE - 1];
+ if (heap->cnt == 0)
+ return NULL;
+
+ lprops = heap->arr[0];
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ return lprops;
+}
+
+/**
+ * ubifs_fast_find_empty - try to find an empty LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for an empty LEB or %NULL if the
+ * function is unable to find an empty LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ if (list_empty(&c->empty_list))
+ return NULL;
+
+ lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ ubifs_assert(lprops->free == c->leb_size);
+ return lprops;
+}
+
+/**
+ * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a freeable LEB or %NULL if the
+ * function is unable to find a freeable LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ if (list_empty(&c->freeable_list))
+ return NULL;
+
+ lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert(!(lprops->flags & LPROPS_INDEX));
+ ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+ ubifs_assert(c->freeable_cnt > 0);
+ return lprops;
+}
+
+/**
+ * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns LEB properties for a freeable index LEB or %NULL if the
+ * function is unable to find a freeable index LEB quickly.
+ */
+const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
+{
+ struct ubifs_lprops *lprops;
+
+ ubifs_assert(mutex_is_locked(&c->lp_mutex));
+
+ if (list_empty(&c->frdi_idx_list))
+ return NULL;
+
+ lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
+ ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
+ ubifs_assert((lprops->flags & LPROPS_INDEX));
+ ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
+ return lprops;
+}
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
new file mode 100644
index 0000000..1a50d4c
--- /dev/null
+++ b/fs/ubifs/lpt.c
@@ -0,0 +1,1105 @@
+/*
+ * 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 the LEB properties tree (LPT) area. The LPT area
+ * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and
+ * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits
+ * between the log and the orphan area.
+ *
+ * The LPT area is like a miniature self-contained file system. It is required
+ * that it never runs out of space, is fast to access and update, and scales
+ * logarithmically. The LEB properties tree is implemented as a wandering tree
+ * much like the TNC, and the LPT area has its own garbage collection.
+ *
+ * The LPT has two slightly different forms called the "small model" and the
+ * "big model". The small model is used when the entire LEB properties table
+ * can be written into a single eraseblock. In that case, garbage collection
+ * consists of just writing the whole table, which therefore makes all other
+ * eraseblocks reusable. In the case of the big model, dirty eraseblocks are
+ * selected for garbage collection, which consists of marking the clean nodes in
+ * that LEB as dirty, and then only the dirty nodes are written out. Also, in
+ * the case of the big model, a table of LEB numbers is saved so that the entire
+ * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first
+ * mounted.
+ */
+
+#include "ubifs.h"
+#include "crc16.h"
+#include <linux/math64.h>
+
+/**
+ * do_calc_lpt_geom - calculate sizes for the LPT area.
+ * @c: the UBIFS file-system description object
+ *
+ * Calculate the sizes of LPT bit fields, nodes, and tree, based on the
+ * properties of the flash and whether LPT is "big" (c->big_lpt).
+ */
+static void do_calc_lpt_geom(struct ubifs_info *c)
+{
+ int i, n, bits, per_leb_wastage, max_pnode_cnt;
+ long long sz, tot_wastage;
+
+ n = c->main_lebs + c->max_leb_cnt - c->leb_cnt;
+ max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
+
+ c->lpt_hght = 1;
+ n = UBIFS_LPT_FANOUT;
+ while (n < max_pnode_cnt) {
+ c->lpt_hght += 1;
+ n <<= UBIFS_LPT_FANOUT_SHIFT;
+ }
+
+ c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
+
+ n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT);
+ c->nnode_cnt = n;
+ for (i = 1; i < c->lpt_hght; i++) {
+ n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
+ c->nnode_cnt += n;
+ }
+
+ c->space_bits = fls(c->leb_size) - 3;
+ c->lpt_lnum_bits = fls(c->lpt_lebs);
+ c->lpt_offs_bits = fls(c->leb_size - 1);
+ c->lpt_spc_bits = fls(c->leb_size);
+
+ n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT);
+ c->pcnt_bits = fls(n - 1);
+
+ c->lnum_bits = fls(c->max_leb_cnt - 1);
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ (c->big_lpt ? c->pcnt_bits : 0) +
+ (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT;
+ c->pnode_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ (c->big_lpt ? c->pcnt_bits : 0) +
+ (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT;
+ c->nnode_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ c->lpt_lebs * c->lpt_spc_bits * 2;
+ c->ltab_sz = (bits + 7) / 8;
+
+ bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
+ c->lnum_bits * c->lsave_cnt;
+ c->lsave_sz = (bits + 7) / 8;
+
+ /* Calculate the minimum LPT size */
+ c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
+ c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
+ c->lpt_sz += c->ltab_sz;
+ if (c->big_lpt)
+ c->lpt_sz += c->lsave_sz;
+
+ /* Add wastage */
+ sz = c->lpt_sz;
+ per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz);
+ sz += per_leb_wastage;
+ tot_wastage = per_leb_wastage;
+ while (sz > c->leb_size) {
+ sz += per_leb_wastage;
+ sz -= c->leb_size;
+ tot_wastage += per_leb_wastage;
+ }
+ tot_wastage += ALIGN(sz, c->min_io_size) - sz;
+ c->lpt_sz += tot_wastage;
+}
+
+/**
+ * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area.
+ * @c: the UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_calc_lpt_geom(struct ubifs_info *c)
+{
+ int lebs_needed;
+ long long sz;
+
+ do_calc_lpt_geom(c);
+
+ /* Verify that lpt_lebs is big enough */
+ sz = c->lpt_sz * 2; /* Must have at least 2 times the size */
+ lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size);
+ if (lebs_needed > c->lpt_lebs) {
+ ubifs_err("too few LPT LEBs");
+ return -EINVAL;
+ }
+
+ /* Verify that ltab fits in a single LEB (since ltab is a single node */
+ if (c->ltab_sz > c->leb_size) {
+ ubifs_err("LPT ltab too big");
+ return -EINVAL;
+ }
+
+ c->check_lpt_free = c->big_lpt;
+ return 0;
+}
+
+/**
+ * ubifs_unpack_bits - unpack bit fields.
+ * @addr: address at which to unpack (passed and next address returned)
+ * @pos: bit position at which to unpack (passed and next position returned)
+ * @nrbits: number of bits of value to unpack (1-32)
+ *
+ * This functions returns the value unpacked.
+ */
+uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits)
+{
+ const int k = 32 - nrbits;
+ uint8_t *p = *addr;
+ int b = *pos;
+ uint32_t uninitialized_var(val);
+ const int bytes = (nrbits + b + 7) >> 3;
+
+ ubifs_assert(nrbits > 0);
+ ubifs_assert(nrbits <= 32);
+ ubifs_assert(*pos >= 0);
+ ubifs_assert(*pos < 8);
+ if (b) {
+ switch (bytes) {
+ case 2:
+ val = p[1];
+ break;
+ case 3:
+ val = p[1] | ((uint32_t)p[2] << 8);
+ break;
+ case 4:
+ val = p[1] | ((uint32_t)p[2] << 8) |
+ ((uint32_t)p[3] << 16);
+ break;
+ case 5:
+ val = p[1] | ((uint32_t)p[2] << 8) |
+ ((uint32_t)p[3] << 16) |
+ ((uint32_t)p[4] << 24);
+ }
+ val <<= (8 - b);
+ val |= *p >> b;
+ nrbits += b;
+ } else {
+ switch (bytes) {
+ case 1:
+ val = p[0];
+ break;
+ case 2:
+ val = p[0] | ((uint32_t)p[1] << 8);
+ break;
+ case 3:
+ val = p[0] | ((uint32_t)p[1] << 8) |
+ ((uint32_t)p[2] << 16);
+ break;
+ case 4:
+ val = p[0] | ((uint32_t)p[1] << 8) |
+ ((uint32_t)p[2] << 16) |
+ ((uint32_t)p[3] << 24);
+ break;
+ }
+ }
+ val <<= k;
+ val >>= k;
+ b = nrbits & 7;
+ p += nrbits >> 3;
+ *addr = p;
+ *pos = b;
+ ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32);
+ return val;
+}
+
+/**
+ * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to which to add dirty space
+ * @dirty: amount of dirty space to add
+ */
+void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty)
+{
+ if (!dirty || !lnum)
+ return;
+ dbg_lp("LEB %d add %d to %d",
+ lnum, dirty, c->ltab[lnum - c->lpt_first].dirty);
+ ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
+ c->ltab[lnum - c->lpt_first].dirty += dirty;
+}
+
+/**
+ * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode for which to add dirt
+ */
+void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode)
+{
+ struct ubifs_nnode *np = nnode->parent;
+
+ if (np)
+ ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum,
+ c->nnode_sz);
+ else {
+ ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz);
+ if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
+ c->lpt_drty_flgs |= LTAB_DIRTY;
+ ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
+ }
+ }
+}
+
+/**
+ * add_pnode_dirt - add dirty space to LPT LEB properties.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode for which to add dirt
+ */
+static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+ ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
+ c->pnode_sz);
+}
+
+/**
+ * calc_nnode_num_from_parent - calculate nnode number.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * The nnode number is a number that uniquely identifies a nnode and can be used
+ * easily to traverse the tree from the root to that nnode.
+ *
+ * This function calculates and returns the nnode number based on the parent's
+ * nnode number and the index in parent.
+ */
+static int calc_nnode_num_from_parent(const struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ int num, shft;
+
+ if (!parent)
+ return 1;
+ shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT;
+ num = parent->num ^ (1 << shft);
+ num |= (UBIFS_LPT_FANOUT + iip) << shft;
+ return num;
+}
+
+/**
+ * calc_pnode_num_from_parent - calculate pnode number.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * The pnode number is a number that uniquely identifies a pnode and can be used
+ * easily to traverse the tree from the root to that pnode.
+ *
+ * This function calculates and returns the pnode number based on the parent's
+ * nnode number and the index in parent.
+ */
+static int calc_pnode_num_from_parent(const struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
+
+ for (i = 0; i < n; i++) {
+ num <<= UBIFS_LPT_FANOUT_SHIFT;
+ num |= pnum & (UBIFS_LPT_FANOUT - 1);
+ pnum >>= UBIFS_LPT_FANOUT_SHIFT;
+ }
+ num <<= UBIFS_LPT_FANOUT_SHIFT;
+ num |= iip;
+ return num;
+}
+
+/**
+ * update_cats - add LEB properties of a pnode to LEB category lists and heaps.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode
+ *
+ * When a pnode is loaded into memory, the LEB properties it contains are added,
+ * by this function, to the LEB category lists and heaps.
+ */
+static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode)
+{
+ int i;
+
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK;
+ int lnum = pnode->lprops[i].lnum;
+
+ if (!lnum)
+ return;
+ ubifs_add_to_cat(c, &pnode->lprops[i], cat);
+ }
+}
+
+/**
+ * replace_cats - add LEB properties of a pnode to LEB category lists and heaps.
+ * @c: UBIFS file-system description object
+ * @old_pnode: pnode copied
+ * @new_pnode: pnode copy
+ *
+ * During commit it is sometimes necessary to copy a pnode
+ * (see dirty_cow_pnode). When that happens, references in
+ * category lists and heaps must be replaced. This function does that.
+ */
+static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode,
+ struct ubifs_pnode *new_pnode)
+{
+ int i;
+
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (!new_pnode->lprops[i].lnum)
+ return;
+ ubifs_replace_cat(c, &old_pnode->lprops[i],
+ &new_pnode->lprops[i]);
+ }
+}
+
+/**
+ * check_lpt_crc - check LPT node crc is correct.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing node
+ * @len: length of node
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int check_lpt_crc(void *buf, int len)
+{
+ int pos = 0;
+ uint8_t *addr = buf;
+ uint16_t crc, calc_crc;
+
+ crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
+ calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
+ len - UBIFS_LPT_CRC_BYTES);
+ if (crc != calc_crc) {
+ ubifs_err("invalid crc in LPT node: crc %hx calc %hx", crc,
+ calc_crc);
+ dbg_dump_stack();
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * check_lpt_type - check LPT node type is correct.
+ * @c: UBIFS file-system description object
+ * @addr: address of type bit field is passed and returned updated here
+ * @pos: position of type bit field is passed and returned updated here
+ * @type: expected type
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int check_lpt_type(uint8_t **addr, int *pos, int type)
+{
+ int node_type;
+
+ node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS);
+ if (node_type != type) {
+ ubifs_err("invalid type (%d) in LPT node type %d", node_type,
+ type);
+ dbg_dump_stack();
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * unpack_pnode - unpack a pnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing packed pnode to unpack
+ * @pnode: pnode structure to fill
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_pnode(const struct ubifs_info *c, void *buf,
+ struct ubifs_pnode *pnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0, err;
+
+ err = check_lpt_type(&addr, &pos, UBIFS_LPT_PNODE);
+ if (err)
+ return err;
+ if (c->big_lpt)
+ pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+ lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits);
+ lprops->free <<= 3;
+ lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits);
+ lprops->dirty <<= 3;
+
+ if (ubifs_unpack_bits(&addr, &pos, 1))
+ lprops->flags = LPROPS_INDEX;
+ else
+ lprops->flags = 0;
+ lprops->flags |= ubifs_categorize_lprops(c, lprops);
+ }
+ err = check_lpt_crc(buf, c->pnode_sz);
+ return err;
+}
+
+/**
+ * ubifs_unpack_nnode - unpack a nnode.
+ * @c: UBIFS file-system description object
+ * @buf: buffer containing packed nnode to unpack
+ * @nnode: nnode structure to fill
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
+ struct ubifs_nnode *nnode)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0, err;
+
+ err = check_lpt_type(&addr, &pos, UBIFS_LPT_NNODE);
+ if (err)
+ return err;
+ if (c->big_lpt)
+ nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int lnum;
+
+ lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) +
+ c->lpt_first;
+ if (lnum == c->lpt_last + 1)
+ lnum = 0;
+ nnode->nbranch[i].lnum = lnum;
+ nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos,
+ c->lpt_offs_bits);
+ }
+ err = check_lpt_crc(buf, c->nnode_sz);
+ return err;
+}
+
+/**
+ * unpack_ltab - unpack the LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ * @buf: buffer from which to unpack
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int unpack_ltab(const struct ubifs_info *c, void *buf)
+{
+ uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
+ int i, pos = 0, err;
+
+ err = check_lpt_type(&addr, &pos, UBIFS_LPT_LTAB);
+ if (err)
+ return err;
+ for (i = 0; i < c->lpt_lebs; i++) {
+ int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
+ int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
+
+ if (free < 0 || free > c->leb_size || dirty < 0 ||
+ dirty > c->leb_size || free + dirty > c->leb_size)
+ return -EINVAL;
+
+ c->ltab[i].free = free;
+ c->ltab[i].dirty = dirty;
+ c->ltab[i].tgc = 0;
+ c->ltab[i].cmt = 0;
+ }
+ err = check_lpt_crc(buf, c->ltab_sz);
+ return err;
+}
+
+/**
+ * validate_nnode - validate a nnode.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode to validate
+ * @parent: parent nnode (or NULL for the root nnode)
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int validate_nnode(const struct ubifs_info *c, struct ubifs_nnode *nnode,
+ struct ubifs_nnode *parent, int iip)
+{
+ int i, lvl, max_offs;
+
+ if (c->big_lpt) {
+ int num = calc_nnode_num_from_parent(c, parent, iip);
+
+ if (nnode->num != num)
+ return -EINVAL;
+ }
+ lvl = parent ? parent->level - 1 : c->lpt_hght;
+ if (lvl < 1)
+ return -EINVAL;
+ if (lvl == 1)
+ max_offs = c->leb_size - c->pnode_sz;
+ else
+ max_offs = c->leb_size - c->nnode_sz;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int lnum = nnode->nbranch[i].lnum;
+ int offs = nnode->nbranch[i].offs;
+
+ if (lnum == 0) {
+ if (offs != 0)
+ return -EINVAL;
+ continue;
+ }
+ if (lnum < c->lpt_first || lnum > c->lpt_last)
+ return -EINVAL;
+ if (offs < 0 || offs > max_offs)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * validate_pnode - validate a pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to validate
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int validate_pnode(const struct ubifs_info *c, struct ubifs_pnode *pnode,
+ struct ubifs_nnode *parent, int iip)
+{
+ int i;
+
+ if (c->big_lpt) {
+ int num = calc_pnode_num_from_parent(c, parent, iip);
+
+ if (pnode->num != num)
+ return -EINVAL;
+ }
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ int free = pnode->lprops[i].free;
+ int dirty = pnode->lprops[i].dirty;
+
+ if (free < 0 || free > c->leb_size || free % c->min_io_size ||
+ (free & 7))
+ return -EINVAL;
+ if (dirty < 0 || dirty > c->leb_size || (dirty & 7))
+ return -EINVAL;
+ if (dirty + free > c->leb_size)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * set_pnode_lnum - set LEB numbers on a pnode.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to update
+ *
+ * This function calculates the LEB numbers for the LEB properties it contains
+ * based on the pnode number.
+ */
+static void set_pnode_lnum(const struct ubifs_info *c,
+ struct ubifs_pnode *pnode)
+{
+ int i, lnum;
+
+ lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (lnum >= c->leb_cnt)
+ return;
+ pnode->lprops[i].lnum = lnum++;
+ }
+}
+
+/**
+ * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode (or NULL for the root)
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch = NULL;
+ struct ubifs_nnode *nnode = NULL;
+ void *buf = c->lpt_nod_buf;
+ int err, lnum, offs;
+
+ if (parent) {
+ branch = &parent->nbranch[iip];
+ lnum = branch->lnum;
+ offs = branch->offs;
+ } else {
+ lnum = c->lpt_lnum;
+ offs = c->lpt_offs;
+ }
+ nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
+ if (!nnode) {
+ err = -ENOMEM;
+ goto out;
+ }
+ if (lnum == 0) {
+ /*
+ * This nnode was not written which just means that the LEB
+ * properties in the subtree below it describe empty LEBs. We
+ * make the nnode as though we had read it, which in fact means
+ * doing almost nothing.
+ */
+ if (c->big_lpt)
+ nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+ } else {
+ err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz);
+ if (err)
+ goto out;
+ err = ubifs_unpack_nnode(c, buf, nnode);
+ if (err)
+ goto out;
+ }
+ err = validate_nnode(c, nnode, parent, iip);
+ if (err)
+ goto out;
+ if (!c->big_lpt)
+ nnode->num = calc_nnode_num_from_parent(c, parent, iip);
+ if (parent) {
+ branch->nnode = nnode;
+ nnode->level = parent->level - 1;
+ } else {
+ c->nroot = nnode;
+ nnode->level = c->lpt_hght;
+ }
+ nnode->parent = parent;
+ nnode->iip = iip;
+ return 0;
+
+out:
+ ubifs_err("error %d reading nnode at %d:%d", err, lnum, offs);
+ kfree(nnode);
+ return err;
+}
+
+/**
+ * read_pnode - read a pnode from flash and link it to the tree in memory.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_pnode *pnode = NULL;
+ void *buf = c->lpt_nod_buf;
+ int err, lnum, offs;
+
+ branch = &parent->nbranch[iip];
+ lnum = branch->lnum;
+ offs = branch->offs;
+ pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
+ if (!pnode) {
+ err = -ENOMEM;
+ goto out;
+ }
+ if (lnum == 0) {
+ /*
+ * This pnode was not written which just means that the LEB
+ * properties in it describe empty LEBs. We make the pnode as
+ * though we had read it.
+ */
+ int i;
+
+ if (c->big_lpt)
+ pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_lprops * const lprops = &pnode->lprops[i];
+
+ lprops->free = c->leb_size;
+ lprops->flags = ubifs_categorize_lprops(c, lprops);
+ }
+ } else {
+ err = ubi_read(c->ubi, lnum, buf, offs, c->pnode_sz);
+ if (err)
+ goto out;
+ err = unpack_pnode(c, buf, pnode);
+ if (err)
+ goto out;
+ }
+ err = validate_pnode(c, pnode, parent, iip);
+ if (err)
+ goto out;
+ if (!c->big_lpt)
+ pnode->num = calc_pnode_num_from_parent(c, parent, iip);
+ branch->pnode = pnode;
+ pnode->parent = parent;
+ pnode->iip = iip;
+ set_pnode_lnum(c, pnode);
+ c->pnodes_have += 1;
+ return 0;
+
+out:
+ ubifs_err("error %d reading pnode at %d:%d", err, lnum, offs);
+ dbg_dump_pnode(c, pnode, parent, iip);
+ dbg_msg("calc num: %d", calc_pnode_num_from_parent(c, parent, iip));
+ kfree(pnode);
+ return err;
+}
+
+/**
+ * read_ltab - read LPT's own lprops table.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int read_ltab(struct ubifs_info *c)
+{
+ int err;
+ void *buf;
+
+ buf = vmalloc(c->ltab_sz);
+ if (!buf)
+ return -ENOMEM;
+ err = ubi_read(c->ubi, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz);
+ if (err)
+ goto out;
+ err = unpack_ltab(c, buf);
+out:
+ vfree(buf);
+ return err;
+}
+
+/**
+ * ubifs_get_nnode - get a nnode.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode (or NULL for the root)
+ * @iip: index in parent
+ *
+ * This function returns a pointer to the nnode on success or a negative error
+ * code on failure.
+ */
+struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_nnode *nnode;
+ int err;
+
+ branch = &parent->nbranch[iip];
+ nnode = branch->nnode;
+ if (nnode)
+ return nnode;
+ err = ubifs_read_nnode(c, parent, iip);
+ if (err)
+ return ERR_PTR(err);
+ return branch->nnode;
+}
+
+/**
+ * ubifs_get_pnode - get a pnode.
+ * @c: UBIFS file-system description object
+ * @parent: parent nnode
+ * @iip: index in parent
+ *
+ * This function returns a pointer to the pnode on success or a negative error
+ * code on failure.
+ */
+struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
+ struct ubifs_nnode *parent, int iip)
+{
+ struct ubifs_nbranch *branch;
+ struct ubifs_pnode *pnode;
+ int err;
+
+ branch = &parent->nbranch[iip];
+ pnode = branch->pnode;
+ if (pnode)
+ return pnode;
+ err = read_pnode(c, parent, iip);
+ if (err)
+ return ERR_PTR(err);
+ update_cats(c, branch->pnode);
+ return branch->pnode;
+}
+
+/**
+ * ubifs_lpt_lookup - lookup LEB properties in the LPT.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to lookup
+ *
+ * This function returns a pointer to the LEB properties on success or a
+ * negative error code on failure.
+ */
+struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum)
+{
+ int err, i, h, iip, shft;
+ struct ubifs_nnode *nnode;
+ struct ubifs_pnode *pnode;
+
+ if (!c->nroot) {
+ err = ubifs_read_nnode(c, NULL, 0);
+ if (err)
+ return ERR_PTR(err);
+ }
+ nnode = c->nroot;
+ i = lnum - c->main_first;
+ shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+ for (h = 1; h < c->lpt_hght; h++) {
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ nnode = ubifs_get_nnode(c, nnode, iip);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ }
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ pnode = ubifs_get_pnode(c, nnode, iip);
+ if (IS_ERR(pnode))
+ return ERR_PTR(PTR_ERR(pnode));
+ iip = (i & (UBIFS_LPT_FANOUT - 1));
+ dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
+ pnode->lprops[iip].free, pnode->lprops[iip].dirty,
+ pnode->lprops[iip].flags);
+ return &pnode->lprops[iip];
+}
+
+/**
+ * dirty_cow_nnode - ensure a nnode is not being committed.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode to check
+ *
+ * Returns dirtied nnode on success or negative error code on failure.
+ */
+static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c,
+ struct ubifs_nnode *nnode)
+{
+ struct ubifs_nnode *n;
+ int i;
+
+ if (!test_bit(COW_CNODE, &nnode->flags)) {
+ /* nnode is not being committed */
+ if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
+ c->dirty_nn_cnt += 1;
+ ubifs_add_nnode_dirt(c, nnode);
+ }
+ return nnode;
+ }
+
+ /* nnode is being committed, so copy it */
+ n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
+ if (unlikely(!n))
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(n, nnode, sizeof(struct ubifs_nnode));
+ n->cnext = NULL;
+ __set_bit(DIRTY_CNODE, &n->flags);
+ __clear_bit(COW_CNODE, &n->flags);
+
+ /* The children now have new parent */
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ struct ubifs_nbranch *branch = &n->nbranch[i];
+
+ if (branch->cnode)
+ branch->cnode->parent = n;
+ }
+
+ ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags));
+ __set_bit(OBSOLETE_CNODE, &nnode->flags);
+
+ c->dirty_nn_cnt += 1;
+ ubifs_add_nnode_dirt(c, nnode);
+ if (nnode->parent)
+ nnode->parent->nbranch[n->iip].nnode = n;
+ else
+ c->nroot = n;
+ return n;
+}
+
+/**
+ * dirty_cow_pnode - ensure a pnode is not being committed.
+ * @c: UBIFS file-system description object
+ * @pnode: pnode to check
+ *
+ * Returns dirtied pnode on success or negative error code on failure.
+ */
+static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c,
+ struct ubifs_pnode *pnode)
+{
+ struct ubifs_pnode *p;
+
+ if (!test_bit(COW_CNODE, &pnode->flags)) {
+ /* pnode is not being committed */
+ if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
+ c->dirty_pn_cnt += 1;
+ add_pnode_dirt(c, pnode);
+ }
+ return pnode;
+ }
+
+ /* pnode is being committed, so copy it */
+ p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
+ if (unlikely(!p))
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(p, pnode, sizeof(struct ubifs_pnode));
+ p->cnext = NULL;
+ __set_bit(DIRTY_CNODE, &p->flags);
+ __clear_bit(COW_CNODE, &p->flags);
+ replace_cats(c, pnode, p);
+
+ ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags));
+ __set_bit(OBSOLETE_CNODE, &pnode->flags);
+
+ c->dirty_pn_cnt += 1;
+ add_pnode_dirt(c, pnode);
+ pnode->parent->nbranch[p->iip].pnode = p;
+ return p;
+}
+
+/**
+ * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to lookup
+ *
+ * This function returns a pointer to the LEB properties on success or a
+ * negative error code on failure.
+ */
+struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum)
+{
+ int err, i, h, iip, shft;
+ struct ubifs_nnode *nnode;
+ struct ubifs_pnode *pnode;
+
+ if (!c->nroot) {
+ err = ubifs_read_nnode(c, NULL, 0);
+ if (err)
+ return ERR_PTR(err);
+ }
+ nnode = c->nroot;
+ nnode = dirty_cow_nnode(c, nnode);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ i = lnum - c->main_first;
+ shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
+ for (h = 1; h < c->lpt_hght; h++) {
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ nnode = ubifs_get_nnode(c, nnode, iip);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ nnode = dirty_cow_nnode(c, nnode);
+ if (IS_ERR(nnode))
+ return ERR_PTR(PTR_ERR(nnode));
+ }
+ iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
+ shft -= UBIFS_LPT_FANOUT_SHIFT;
+ pnode = ubifs_get_pnode(c, nnode, iip);
+ if (IS_ERR(pnode))
+ return ERR_PTR(PTR_ERR(pnode));
+ pnode = dirty_cow_pnode(c, pnode);
+ if (IS_ERR(pnode))
+ return ERR_PTR(PTR_ERR(pnode));
+ iip = (i & (UBIFS_LPT_FANOUT - 1));
+ dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
+ pnode->lprops[iip].free, pnode->lprops[iip].dirty,
+ pnode->lprops[iip].flags);
+ ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags));
+ return &pnode->lprops[iip];
+}
+
+/**
+ * lpt_init_rd - initialize the LPT for reading.
+ * @c: UBIFS file-system description object
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+static int lpt_init_rd(struct ubifs_info *c)
+{
+ int err, i;
+
+ c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
+ if (!c->ltab)
+ return -ENOMEM;
+
+ i = max_t(int, c->nnode_sz, c->pnode_sz);
+ c->lpt_nod_buf = kmalloc(i, GFP_KERNEL);
+ if (!c->lpt_nod_buf)
+ return -ENOMEM;
+
+ for (i = 0; i < LPROPS_HEAP_CNT; i++) {
+ c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ,
+ GFP_KERNEL);
+ if (!c->lpt_heap[i].arr)
+ return -ENOMEM;
+ c->lpt_heap[i].cnt = 0;
+ c->lpt_heap[i].max_cnt = LPT_HEAP_SZ;
+ }
+
+ c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL);
+ if (!c->dirty_idx.arr)
+ return -ENOMEM;
+ c->dirty_idx.cnt = 0;
+ c->dirty_idx.max_cnt = LPT_HEAP_SZ;
+
+ err = read_ltab(c);
+ if (err)
+ return err;
+
+ dbg_lp("space_bits %d", c->space_bits);
+ dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
+ dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
+ dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
+ dbg_lp("pcnt_bits %d", c->pcnt_bits);
+ dbg_lp("lnum_bits %d", c->lnum_bits);
+ dbg_lp("pnode_sz %d", c->pnode_sz);
+ dbg_lp("nnode_sz %d", c->nnode_sz);
+ dbg_lp("ltab_sz %d", c->ltab_sz);
+ dbg_lp("lsave_sz %d", c->lsave_sz);
+ dbg_lp("lsave_cnt %d", c->lsave_cnt);
+ dbg_lp("lpt_hght %d", c->lpt_hght);
+ dbg_lp("big_lpt %d", c->big_lpt);
+ dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
+ dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
+ dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
+ if (c->big_lpt)
+ dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
+
+ return 0;
+}
+
+/**
+ * ubifs_lpt_init - initialize the LPT.
+ * @c: UBIFS file-system description object
+ * @rd: whether to initialize lpt for reading
+ * @wr: whether to initialize lpt for writing
+ *
+ * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true
+ * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is
+ * true.
+ *
+ * This function returns %0 on success and a negative error code on failure.
+ */
+int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr)
+{
+ int err;
+
+ if (rd) {
+ err = lpt_init_rd(c);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
new file mode 100644
index 0000000..c0af818
--- /dev/null
+++ b/fs/ubifs/lpt_commit.c
@@ -0,0 +1,171 @@
+/*
+ * 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 commit-related functionality of the LEB properties
+ * subsystem.
+ */
+
+#include "crc16.h"
+#include "ubifs.h"
+
+/**
+ * free_obsolete_cnodes - free obsolete cnodes for commit end.
+ * @c: UBIFS file-system description object
+ */
+static void free_obsolete_cnodes(struct ubifs_info *c)
+{
+ struct ubifs_cnode *cnode, *cnext;
+
+ cnext = c->lpt_cnext;
+ if (!cnext)
+ return;
+ do {
+ cnode = cnext;
+ cnext = cnode->cnext;
+ if (test_bit(OBSOLETE_CNODE, &cnode->flags))
+ kfree(cnode);
+ else
+ cnode->cnext = NULL;
+ } while (cnext != c->lpt_cnext);
+ c->lpt_cnext = NULL;
+}
+
+/**
+ * first_nnode - find the first nnode in memory.
+ * @c: UBIFS file-system description object
+ * @hght: height of tree where nnode found is returned here
+ *
+ * This function returns a pointer to the nnode found or %NULL if no nnode is
+ * found. This function is a helper to 'ubifs_lpt_free()'.
+ */
+static struct ubifs_nnode *first_nnode(struct ubifs_info *c, int *hght)
+{
+ struct ubifs_nnode *nnode;
+ int h, i, found;
+
+ nnode = c->nroot;
+ *hght = 0;
+ if (!nnode)
+ return NULL;
+ for (h = 1; h < c->lpt_hght; h++) {
+ found = 0;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (nnode->nbranch[i].nnode) {
+ found = 1;
+ nnode = nnode->nbranch[i].nnode;
+ *hght = h;
+ break;
+ }
+ }
+ if (!found)
+ break;
+ }
+ return nnode;
+}
+
+/**
+ * next_nnode - find the next nnode in memory.
+ * @c: UBIFS file-system description object
+ * @nnode: nnode from which to start.
+ * @hght: height of tree where nnode is, is passed and returned here
+ *
+ * This function returns a pointer to the nnode found or %NULL if no nnode is
+ * found. This function is a helper to 'ubifs_lpt_free()'.
+ */
+static struct ubifs_nnode *next_nnode(struct ubifs_info *c,
+ struct ubifs_nnode *nnode, int *hght)
+{
+ struct ubifs_nnode *parent;
+ int iip, h, i, found;
+
+ parent = nnode->parent;
+ if (!parent)
+ return NULL;
+ if (nnode->iip == UBIFS_LPT_FANOUT - 1) {
+ *hght -= 1;
+ return parent;
+ }
+ for (iip = nnode->iip + 1; iip < UBIFS_LPT_FANOUT; iip++) {
+ nnode = parent->nbranch[iip].nnode;
+ if (nnode)
+ break;
+ }
+ if (!nnode) {
+ *hght -= 1;
+ return parent;
+ }
+ for (h = *hght + 1; h < c->lpt_hght; h++) {
+ found = 0;
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+ if (nnode->nbranch[i].nnode) {
+ found = 1;
+ nnode = nnode->nbranch[i].nnode;
+ *hght = h;
+ break;
+ }
+ }
+ if (!found)
+ break;
+ }
+ return nnode;
+}
+
+/**
+ * ubifs_lpt_free - free resources owned by the LPT.
+ * @c: UBIFS file-system description object
+ * @wr_only: free only resources used for writing
+ */
+void ubifs_lpt_free(struct ubifs_info *c, int wr_only)
+{
+ struct ubifs_nnode *nnode;
+ int i, hght;
+
+ /* Free write-only things first */
+
+ free_obsolete_cnodes(c); /* Leftover from a failed commit */
+
+ vfree(c->ltab_cmt);
+ c->ltab_cmt = NULL;
+ vfree(c->lpt_buf);
+ c->lpt_buf = NULL;
+ kfree(c->lsave);
+ c->lsave = NULL;
+
+ if (wr_only)
+ return;
+
+ /* Now free the rest */
+
+ nnode = first_nnode(c, &hght);
+ while (nnode) {
+ for (i = 0; i < UBIFS_LPT_FANOUT; i++)
+ kfree(nnode->nbranch[i].nnode);
+ nnode = next_nnode(c, nnode, &hght);
+ }
+ for (i = 0; i < LPROPS_HEAP_CNT; i++)
+ kfree(c->lpt_heap[i].arr);
+ kfree(c->dirty_idx.arr);
+ kfree(c->nroot);
+ vfree(c->ltab);
+ kfree(c->lpt_nod_buf);
+}
--
1.6.1.3
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