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Diffstat (limited to 'fs/ubifs/journal.c')
| -rw-r--r-- | fs/ubifs/journal.c | 1387 |
1 files changed, 1387 insertions, 0 deletions
diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c new file mode 100644 index 000000000000..283155abe5f5 --- /dev/null +++ b/fs/ubifs/journal.c @@ -0,0 +1,1387 @@ +/* + * This file is part of UBIFS. + * + * Copyright (C) 2006-2008 Nokia Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 51 + * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Authors: Artem Bityutskiy (Битюцкий Артём) + * Adrian Hunter + */ + +/* + * This file implements UBIFS journal. + * + * The journal consists of 2 parts - the log and bud LEBs. The log has fixed + * length and position, while a bud logical eraseblock is any LEB in the main + * area. Buds contain file system data - data nodes, inode nodes, etc. The log + * contains only references to buds and some other stuff like commit + * start node. The idea is that when we commit the journal, we do + * not copy the data, the buds just become indexed. Since after the commit the + * nodes in bud eraseblocks become leaf nodes of the file system index tree, we + * use term "bud". Analogy is obvious, bud eraseblocks contain nodes which will + * become leafs in the future. + * + * The journal is multi-headed because we want to write data to the journal as + * optimally as possible. It is nice to have nodes belonging to the same inode + * in one LEB, so we may write data owned by different inodes to different + * journal heads, although at present only one data head is used. + * + * For recovery reasons, the base head contains all inode nodes, all directory + * entry nodes and all truncate nodes. This means that the other heads contain + * only data nodes. + * + * Bud LEBs may be half-indexed. For example, if the bud was not full at the + * time of commit, the bud is retained to continue to be used in the journal, + * even though the "front" of the LEB is now indexed. In that case, the log + * reference contains the offset where the bud starts for the purposes of the + * journal. + * + * The journal size has to be limited, because the larger is the journal, the + * longer it takes to mount UBIFS (scanning the journal) and the more memory it + * takes (indexing in the TNC). + * + * All the journal write operations like 'ubifs_jnl_update()' here, which write + * multiple UBIFS nodes to the journal at one go, are atomic with respect to + * unclean reboots. Should the unclean reboot happen, the recovery code drops + * all the nodes. + */ + +#include "ubifs.h" + +/** + * zero_ino_node_unused - zero out unused fields of an on-flash inode node. + * @ino: the inode to zero out + */ +static inline void zero_ino_node_unused(struct ubifs_ino_node *ino) +{ + memset(ino->padding1, 0, 4); + memset(ino->padding2, 0, 26); +} + +/** + * zero_dent_node_unused - zero out unused fields of an on-flash directory + * entry node. + * @dent: the directory entry to zero out + */ +static inline void zero_dent_node_unused(struct ubifs_dent_node *dent) +{ + dent->padding1 = 0; + memset(dent->padding2, 0, 4); +} + +/** + * zero_data_node_unused - zero out unused fields of an on-flash data node. + * @data: the data node to zero out + */ +static inline void zero_data_node_unused(struct ubifs_data_node *data) +{ + memset(data->padding, 0, 2); +} + +/** + * zero_trun_node_unused - zero out unused fields of an on-flash truncation + * node. + * @trun: the truncation node to zero out + */ +static inline void zero_trun_node_unused(struct ubifs_trun_node *trun) +{ + memset(trun->padding, 0, 12); +} + +/** + * reserve_space - reserve space in the journal. + * @c: UBIFS file-system description object + * @jhead: journal head number + * @len: node length + * + * This function reserves space in journal head @head. If the reservation + * succeeded, the journal head stays locked and later has to be unlocked using + * 'release_head()'. 'write_node()' and 'write_head()' functions also unlock + * it. Returns zero in case of success, %-EAGAIN if commit has to be done, and + * other negative error codes in case of other failures. + */ +static int reserve_space(struct ubifs_info *c, int jhead, int len) +{ + int err = 0, err1, retries = 0, avail, lnum, offs, free, squeeze; + struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf; + + /* + * Typically, the base head has smaller nodes written to it, so it is + * better to try to allocate space at the ends of eraseblocks. This is + * what the squeeze parameter does. + */ + squeeze = (jhead == BASEHD); +again: + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + + if (c->ro_media) { + err = -EROFS; + goto out_unlock; + } + + avail = c->leb_size - wbuf->offs - wbuf->used; + if (wbuf->lnum != -1 && avail >= len) + return 0; + + /* + * Write buffer wasn't seek'ed or there is no enough space - look for an + * LEB with some empty space. + */ + lnum = ubifs_find_free_space(c, len, &free, squeeze); + if (lnum >= 0) { + /* Found an LEB, add it to the journal head */ + offs = c->leb_size - free; + err = ubifs_add_bud_to_log(c, jhead, lnum, offs); + if (err) + goto out_return; + /* A new bud was successfully allocated and added to the log */ + goto out; + } + + err = lnum; + if (err != -ENOSPC) + goto out_unlock; + + /* + * No free space, we have to run garbage collector to make + * some. But the write-buffer mutex has to be unlocked because + * GC also takes it. + */ + dbg_jnl("no free space jhead %d, run GC", jhead); + mutex_unlock(&wbuf->io_mutex); + + lnum = ubifs_garbage_collect(c, 0); + if (lnum < 0) { + err = lnum; + if (err != -ENOSPC) + return err; + + /* + * GC could not make a free LEB. But someone else may + * have allocated new bud for this journal head, + * because we dropped @wbuf->io_mutex, so try once + * again. + */ + dbg_jnl("GC couldn't make a free LEB for jhead %d", jhead); + if (retries++ < 2) { + dbg_jnl("retry (%d)", retries); + goto again; + } + + dbg_jnl("return -ENOSPC"); + return err; + } + + mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead); + dbg_jnl("got LEB %d for jhead %d", lnum, jhead); + avail = c->leb_size - wbuf->offs - wbuf->used; + + if (wbuf->lnum != -1 && avail >= len) { + /* + * Someone else has switched the journal head and we have + * enough space now. This happens when more then one process is + * trying to write to the same journal head at the same time. + */ + dbg_jnl("return LEB %d back, already have LEB %d:%d", + lnum, wbuf->lnum, wbuf->offs + wbuf->used); + err = ubifs_return_leb(c, lnum); + if (err) + goto out_unlock; + return 0; + } + + err = ubifs_add_bud_to_log(c, jhead, lnum, 0); + if (err) + goto out_return; + offs = 0; + +out: + err = ubifs_wbuf_seek_nolock(wbuf, lnum, offs, UBI_SHORTTERM); + if (err) + goto out_unlock; + + return 0; + +out_unlock: + mutex_unlock(&wbuf->io_mutex); + return err; + +out_return: + /* An error occurred and the LEB has to be returned to lprops */ + ubifs_assert(err < 0); + err1 = ubifs_return_leb(c, lnum); + if (err1 && err == -EAGAIN) + /* + * Return original error code only if it is not %-EAGAIN, + * which is not really an error. Otherwise, return the error + * code of 'ubifs_return_leb()'. + */ + err = err1; + mutex_unlock(&wbuf->io_mutex); + return err; +} + +/** + * write_node - write node to a journal head. + * @c: UBIFS file-system description object + * @jhead: journal head + * @node: node to write + * @len: node length + * @lnum: LEB number written is returned here + * @offs: offset written is returned here + * + * This function writes a node to reserved space of journal head @jhead. + * Returns zero in case of success and a negative error code in case of + * failure. + */ +static int write_node(struct ubifs_info *c, int jhead, void *node, int len, + int *lnum, int *offs) +{ + struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf; + + ubifs_assert(jhead != GCHD); + + *lnum = c->jheads[jhead].wbuf.lnum; + *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used; + + dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len); + ubifs_prepare_node(c, node, len, 0); + + return ubifs_wbuf_write_nolock(wbuf, node, len); +} + +/** + * write_head - write data to a journal head. + * @c: UBIFS file-system description object + * @jhead: journal head + * @buf: buffer to write + * @len: length to write + * @lnum: LEB number written is returned here + * @offs: offset written is returned here + * @sync: non-zero if the write-buffer has to by synchronized + * + * This function is the same as 'write_node()' but it does not assume the + * buffer it is writing is a node, so it does not prepare it (which means + * initializing common header and calculating CRC). + */ +static int write_head(struct ubifs_info *c, int jhead, void *buf, int len, + int *lnum, int *offs, int sync) +{ + int err; + struct ubifs_wbuf *wbuf = &c->jheads[jhead].wbuf; + + ubifs_assert(jhead != GCHD); + + *lnum = c->jheads[jhead].wbuf.lnum; + *offs = c->jheads[jhead].wbuf.offs + c->jheads[jhead].wbuf.used; + dbg_jnl("jhead %d, LEB %d:%d, len %d", jhead, *lnum, *offs, len); + + err = ubifs_wbuf_write_nolock(wbuf, buf, len); + if (err) + return err; + if (sync) + err = ubifs_wbuf_sync_nolock(wbuf); + return err; +} + +/** + * make_reservation - reserve journal space. + * @c: UBIFS file-system description object + * @jhead: journal head + * @len: how many bytes to reserve + * + * This function makes space reservation in journal head @jhead. The function + * takes the commit lock and locks the journal head, and the caller has to + * unlock the head and finish the reservation with 'finish_reservation()'. + * Returns zero in case of success and a negative error code in case of + * failure. + * + * Note, the journal head may be unlocked as soon as the data is written, while + * the commit lock has to be released after the data has been added to the + * TNC. + */ +static int make_reservation(struct ubifs_info *c, int jhead, int len) +{ + int err, cmt_retries = 0, nospc_retries = 0; + +again: + down_read(&c->commit_sem); + err = reserve_space(c, jhead, len); + if (!err) + return 0; + up_read(&c->commit_sem); + + if (err == -ENOSPC) { + /* + * GC could not make any progress. We should try to commit + * once because it could make some dirty space and GC would + * make progress, so make the error -EAGAIN so that the below + * will commit and re-try. + */ + if (nospc_retries++ < 2) { + dbg_jnl("no space, retry"); + err = -EAGAIN; + } + + /* + * This means that the budgeting is incorrect. We always have + * to be able to write to the media, because all operations are + * budgeted. Deletions are not budgeted, though, but we reserve + * an extra LEB for them. + */ + } + + if (err != -EAGAIN) + goto out; + + /* + * -EAGAIN means that the journal is full or too large, or the above + * code wants to do one commit. Do this and re-try. + */ + if (cmt_retries > 128) { + /* + * This should not happen unless the journal size limitations + * are too tough. + */ + ubifs_err("stuck in space allocation"); + err = -ENOSPC; + goto out; + } else if (cmt_retries > 32) + ubifs_warn("too many space allocation re-tries (%d)", + cmt_retries); + + dbg_jnl("-EAGAIN, commit and retry (retried %d times)", + cmt_retries); + cmt_retries += 1; + + err = ubifs_run_commit(c); + if (err) + return err; + goto again; + +out: + ubifs_err("cannot reserve %d bytes in jhead %d, error %d", + len, jhead, err); + if (err == -ENOSPC) { + /* This are some budgeting problems, print useful information */ + down_write(&c->commit_sem); + spin_lock(&c->space_lock); + dbg_dump_stack(); + dbg_dump_budg(c); + spin_unlock(&c->space_lock); + dbg_dump_lprops(c); + cmt_retries = dbg_check_lprops(c); + up_write(&c->commit_sem); + } + return err; +} + +/** + * release_head - release a journal head. + * @c: UBIFS file-system description object + * @jhead: journal head + * + * This function releases journal head @jhead which was locked by + * the 'make_reservation()' function. It has to be called after each successful + * 'make_reservation()' invocation. + */ +static inline void release_head(struct ubifs_info *c, int jhead) +{ + mutex_unlock(&c->jheads[jhead].wbuf.io_mutex); +} + +/** + * finish_reservation - finish a reservation. + * @c: UBIFS file-system description object + * + * This function finishes journal space reservation. It must be called after + * 'make_reservation()'. + */ +static void finish_reservation(struct ubifs_info *c) +{ + up_read(&c->commit_sem); +} + +/** + * get_dent_type - translate VFS inode mode to UBIFS directory entry type. + * @mode: inode mode + */ +static int get_dent_type(int mode) +{ + switch (mode & S_IFMT) { + case S_IFREG: + return UBIFS_ITYPE_REG; + case S_IFDIR: + return UBIFS_ITYPE_DIR; + case S_IFLNK: + return UBIFS_ITYPE_LNK; + case S_IFBLK: + return UBIFS_ITYPE_BLK; + case S_IFCHR: + return UBIFS_ITYPE_CHR; + case S_IFIFO: + return UBIFS_ITYPE_FIFO; + case S_IFSOCK: + return UBIFS_ITYPE_SOCK; + default: + BUG(); + } + return 0; +} + +/** + * pack_inode - pack an inode node. + * @c: UBIFS file-system description object + * @ino: buffer in which to pack inode node + * @inode: inode to pack + * @last: indicates the last node of the group + * @last_reference: non-zero if this is a deletion inode + */ +static void pack_inode(struct ubifs_info *c, struct ubifs_ino_node *ino, + const struct inode *inode, int last, + int last_reference) +{ + int data_len = 0; + struct ubifs_inode *ui = ubifs_inode(inode); + + ino->ch.node_type = UBIFS_INO_NODE; + ino_key_init_flash(c, &ino->key, inode->i_ino); + ino->creat_sqnum = cpu_to_le64(ui->creat_sqnum); + ino->atime_sec = cpu_to_le64(inode->i_atime.tv_sec); + ino->atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec); + ino->ctime_sec = cpu_to_le64(inode->i_ctime.tv_sec); + ino->ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec); + ino->mtime_sec = cpu_to_le64(inode->i_mtime.tv_sec); + ino->mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec); + ino->uid = cpu_to_le32(inode->i_uid); + ino->gid = cpu_to_le32(inode->i_gid); + ino->mode = cpu_to_le32(inode->i_mode); + ino->flags = cpu_to_le32(ui->flags); + ino->size = cpu_to_le64(ui->ui_size); + ino->nlink = cpu_to_le32(inode->i_nlink); + ino->compr_type = cpu_to_le16(ui->compr_type); + ino->data_len = cpu_to_le32(ui->data_len); + ino->xattr_cnt = cpu_to_le32(ui->xattr_cnt); + ino->xattr_size = cpu_to_le32(ui->xattr_size); + ino->xattr_names = cpu_to_le32(ui->xattr_names); + zero_ino_node_unused(ino); + + /* + * Drop the attached data if this is a deletion inode, the data is not + * needed anymore. + */ + if (!last_reference) { + memcpy(ino->data, ui->data, ui->data_len); + data_len = ui->data_len; + } + + ubifs_prep_grp_node(c, ino, UBIFS_INO_NODE_SZ + data_len, last); +} + +/** + * mark_inode_clean - mark UBIFS inode as clean. + * @c: UBIFS file-system description object + * @ui: UBIFS inode to mark as clean + * + * This helper function marks UBIFS inode @ui as clean by cleaning the + * @ui->dirty flag and releasing its budget. Note, VFS may still treat the + * inode as dirty and try to write it back, but 'ubifs_write_inode()' would + * just do nothing. + */ +static void mark_inode_clean(struct ubifs_info *c, struct ubifs_inode *ui) +{ + if (ui->dirty) + ubifs_release_dirty_inode_budget(c, ui); + ui->dirty = 0; +} + +/** + * ubifs_jnl_update - update inode. + * @c: UBIFS file-system description object + * @dir: parent inode or host inode in case of extended attributes + * @nm: directory entry name + * @inode: inode to update + * @deletion: indicates a directory entry deletion i.e unlink or rmdir + * @xent: non-zero if the directory entry is an extended attribute entry + * + * This function updates an inode by writing a directory entry (or extended + * attribute entry), the inode itself, and the parent directory inode (or the + * host inode) to the journal. + * + * The function writes the host inode @dir last, which is important in case of + * extended attributes. Indeed, then we guarantee that if the host inode gets + * synchronized (with 'fsync()'), and the write-buffer it sits in gets flushed, + * the extended attribute inode gets flushed too. And this is exactly what the + * user expects - synchronizing the host inode synchronizes its extended + * attributes. Similarly, this guarantees that if @dir is synchronized, its + * directory entry corresponding to @nm gets synchronized too. + * + * If the inode (@inode) or the parent directory (@dir) are synchronous, this + * function synchronizes the write-buffer. + * + * This function marks the @dir and @inode inodes as clean and returns zero on + * success. In case of failure, a negative error code is returned. + */ +int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir, + const struct qstr *nm, const struct inode *inode, + int deletion, int xent) +{ + int err, dlen, ilen, len, lnum, ino_offs, dent_offs; + int aligned_dlen, aligned_ilen, sync = IS_DIRSYNC(dir); + int last_reference = !!(deletion && inode->i_nlink == 0); + struct ubifs_inode *ui = ubifs_inode(inode); + struct ubifs_inode *dir_ui = ubifs_inode(dir); + struct ubifs_dent_node *dent; + struct ubifs_ino_node *ino; + union ubifs_key dent_key, ino_key; + + dbg_jnl("ino %lu, dent '%.*s', data len %d in dir ino %lu", + inode->i_ino, nm->len, nm->name, ui->data_len, dir->i_ino); + ubifs_assert(dir_ui->data_len == 0); + ubifs_assert(mutex_is_locked(&dir_ui->ui_mutex)); + + dlen = UBIFS_DENT_NODE_SZ + nm->len + 1; + ilen = UBIFS_INO_NODE_SZ; + + /* + * If the last reference to the inode is being deleted, then there is + * no need to attach and write inode data, it is being deleted anyway. + * And if the inode is being deleted, no need to synchronize + * write-buffer even if the inode is synchronous. + */ + if (!last_reference) { + ilen += ui->data_len; + sync |= IS_SYNC(inode); + } + + aligned_dlen = ALIGN(dlen, 8); + aligned_ilen = ALIGN(ilen, 8); + len = aligned_dlen + aligned_ilen + UBIFS_INO_NODE_SZ; + dent = kmalloc(len, GFP_NOFS); + if (!dent) + return -ENOMEM; + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, BASEHD, len); + if (err) + goto out_free; + + if (!xent) { + dent->ch.node_type = UBIFS_DENT_NODE; + dent_key_init(c, &dent_key, dir->i_ino, nm); + } else { + dent->ch.node_type = UBIFS_XENT_NODE; + xent_key_init(c, &dent_key, dir->i_ino, nm); + } + + key_write(c, &dent_key, dent->key); + dent->inum = deletion ? 0 : cpu_to_le64(inode->i_ino); + dent->type = get_dent_type(inode->i_mode); + dent->nlen = cpu_to_le16(nm->len); + memcpy(dent->name, nm->name, nm->len); + dent->name[nm->len] = '\0'; + zero_dent_node_unused(dent); + ubifs_prep_grp_node(c, dent, dlen, 0); + + ino = (void *)dent + aligned_dlen; + pack_inode(c, ino, inode, 0, last_reference); + ino = (void *)ino + aligned_ilen; + pack_inode(c, ino, dir, 1, 0); + + if (last_reference) { + err = ubifs_add_orphan(c, inode->i_ino); + if (err) { + release_head(c, BASEHD); + goto out_finish; + } + } + + err = write_head(c, BASEHD, dent, len, &lnum, &dent_offs, sync); + if (err) + goto out_release; + if (!sync) { + struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf; + + ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino); + ubifs_wbuf_add_ino_nolock(wbuf, dir->i_ino); + } + release_head(c, BASEHD); + kfree(dent); + + if (deletion) { + err = ubifs_tnc_remove_nm(c, &dent_key, nm); + if (err) + goto out_ro; + err = ubifs_add_dirt(c, lnum, dlen); + } else + err = ubifs_tnc_add_nm(c, &dent_key, lnum, dent_offs, dlen, nm); + if (err) + goto out_ro; + + /* + * Note, we do not remove the inode from TNC even if the last reference + * to it has just been deleted, because the inode may still be opened. + * Instead, the inode has been added to orphan lists and the orphan + * subsystem will take further care about it. + */ + ino_key_init(c, &ino_key, inode->i_ino); + ino_offs = dent_offs + aligned_dlen; + err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, ilen); + if (err) + goto out_ro; + + ino_key_init(c, &ino_key, dir->i_ino); + ino_offs += aligned_ilen; + err = ubifs_tnc_add(c, &ino_key, lnum, ino_offs, UBIFS_INO_NODE_SZ); + if (err) + goto out_ro; + + finish_reservation(c); + spin_lock(&ui->ui_lock); + ui->synced_i_size = ui->ui_size; + spin_unlock(&ui->ui_lock); + mark_inode_clean(c, ui); + mark_inode_clean(c, dir_ui); + return 0; + +out_finish: + finish_reservation(c); +out_free: + kfree(dent); + return err; + +out_release: + release_head(c, BASEHD); +out_ro: + ubifs_ro_mode(c, err); + if (last_reference) + ubifs_delete_orphan(c, inode->i_ino); + finish_reservation(c); + return err; +} + +/** + * ubifs_jnl_write_data - write a data node to the journal. + * @c: UBIFS file-system description object + * @inode: inode the data node belongs to + * @key: node key + * @buf: buffer to write + * @len: data length (must not exceed %UBIFS_BLOCK_SIZE) + * + * This function writes a data node to the journal. Returns %0 if the data node + * was successfully written, and a negative error code in case of failure. + */ +int ubifs_jnl_write_data(struct ubifs_info *c, const struct inode *inode, + const union ubifs_key *key, const void *buf, int len) +{ + struct ubifs_data_node *data; + int err, lnum, offs, compr_type, out_len; + int dlen = UBIFS_DATA_NODE_SZ + UBIFS_BLOCK_SIZE * WORST_COMPR_FACTOR; + struct ubifs_inode *ui = ubifs_inode(inode); + + dbg_jnl("ino %lu, blk %u, len %d, key %s", key_inum(c, key), + key_block(c, key), len, DBGKEY(key)); + ubifs_assert(len <= UBIFS_BLOCK_SIZE); + + data = kmalloc(dlen, GFP_NOFS); + if (!data) + return -ENOMEM; + + data->ch.node_type = UBIFS_DATA_NODE; + key_write(c, key, &data->key); + data->size = cpu_to_le32(len); + zero_data_node_unused(data); + + if (!(ui->flags && UBIFS_COMPR_FL)) + /* Compression is disabled for this inode */ + compr_type = UBIFS_COMPR_NONE; + else + compr_type = ui->compr_type; + + out_len = dlen - UBIFS_DATA_NODE_SZ; + ubifs_compress(buf, len, &data->data, &out_len, &compr_type); + ubifs_assert(out_len <= UBIFS_BLOCK_SIZE); + + dlen = UBIFS_DATA_NODE_SZ + out_len; + data->compr_type = cpu_to_le16(compr_type); + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, DATAHD, dlen); + if (err) + goto out_free; + + err = write_node(c, DATAHD, data, dlen, &lnum, &offs); + if (err) + goto out_release; + ubifs_wbuf_add_ino_nolock(&c->jheads[DATAHD].wbuf, key_inum(c, key)); + release_head(c, DATAHD); + + err = ubifs_tnc_add(c, key, lnum, offs, dlen); + if (err) + goto out_ro; + + finish_reservation(c); + kfree(data); + return 0; + +out_release: + release_head(c, DATAHD); +out_ro: + ubifs_ro_mode(c, err); + finish_reservation(c); +out_free: + kfree(data); + return err; +} + +/** + * ubifs_jnl_write_inode - flush inode to the journal. + * @c: UBIFS file-system description object + * @inode: inode to flush + * @deletion: inode has been deleted + * + * This function writes inode @inode to the journal. If the inode is + * synchronous, it also synchronizes the write-buffer. Returns zero in case of + * success and a negative error code in case of failure. + */ +int ubifs_jnl_write_inode(struct ubifs_info *c, const struct inode *inode, + int deletion) +{ + int err, len, lnum, offs, sync = 0; + struct ubifs_ino_node *ino; + struct ubifs_inode *ui = ubifs_inode(inode); + + dbg_jnl("ino %lu%s", inode->i_ino, + deletion ? " (last reference)" : ""); + if (deletion) + ubifs_assert(inode->i_nlink == 0); + + len = UBIFS_INO_NODE_SZ; + /* + * If the inode is being deleted, do not write the attached data. No + * need to synchronize the write-buffer either. + */ + if (!deletion) { + len += ui->data_len; + sync = IS_SYNC(inode); + } + ino = kmalloc(len, GFP_NOFS); + if (!ino) + return -ENOMEM; + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, BASEHD, len); + if (err) + goto out_free; + + pack_inode(c, ino, inode, 1, deletion); + err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync); + if (err) + goto out_release; + if (!sync) + ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, + inode->i_ino); + release_head(c, BASEHD); + + if (deletion) { + err = ubifs_tnc_remove_ino(c, inode->i_ino); + if (err) + goto out_ro; + ubifs_delete_orphan(c, inode->i_ino); + err = ubifs_add_dirt(c, lnum, len); + } else { + union ubifs_key key; + + ino_key_init(c, &key, inode->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs, len); + } + if (err) + goto out_ro; + + finish_reservation(c); + spin_lock(&ui->ui_lock); + ui->synced_i_size = ui->ui_size; + spin_unlock(&ui->ui_lock); + kfree(ino); + return 0; + +out_release: + release_head(c, BASEHD); +out_ro: + ubifs_ro_mode(c, err); + finish_reservation(c); +out_free: + kfree(ino); + return err; +} + +/** + * ubifs_jnl_rename - rename a directory entry. + * @c: UBIFS file-system description object + * @old_dir: parent inode of directory entry to rename + * @old_dentry: directory entry to rename + * @new_dir: parent inode of directory entry to rename + * @new_dentry: new directory entry (or directory entry to replace) + * @sync: non-zero if the write-buffer has to be synchronized + * + * This function implements the re-name operation which may involve writing up + * to 3 inodes and 2 directory entries. It marks the written inodes as clean + * and returns zero on success. In case of failure, a negative error code is + * returned. + */ +int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir, + const struct dentry *old_dentry, + const struct inode *new_dir, + const struct dentry *new_dentry, int sync) +{ + void *p; + union ubifs_key key; + struct ubifs_dent_node *dent, *dent2; + int err, dlen1, dlen2, ilen, lnum, offs, len; + const struct inode *old_inode = old_dentry->d_inode; + const struct inode *new_inode = new_dentry->d_inode; + int aligned_dlen1, aligned_dlen2, plen = UBIFS_INO_NODE_SZ; + int last_reference = !!(new_inode && new_inode->i_nlink == 0); + int move = (old_dir != new_dir); + struct ubifs_inode *uninitialized_var(new_ui); + + dbg_jnl("dent '%.*s' in dir ino %lu to dent '%.*s' in dir ino %lu", + old_dentry->d_name.len, old_dentry->d_name.name, + old_dir->i_ino, new_dentry->d_name.len, + new_dentry->d_name.name, new_dir->i_ino); + ubifs_assert(ubifs_inode(old_dir)->data_len == 0); + ubifs_assert(ubifs_inode(new_dir)->data_len == 0); + ubifs_assert(mutex_is_locked(&ubifs_inode(old_dir)->ui_mutex)); + ubifs_assert(mutex_is_locked(&ubifs_inode(new_dir)->ui_mutex)); + + dlen1 = UBIFS_DENT_NODE_SZ + new_dentry->d_name.len + 1; + dlen2 = UBIFS_DENT_NODE_SZ + old_dentry->d_name.len + 1; + if (new_inode) { + new_ui = ubifs_inode(new_inode); + ubifs_assert(mutex_is_locked(&new_ui->ui_mutex)); + ilen = UBIFS_INO_NODE_SZ; + if (!last_reference) + ilen += new_ui->data_len; + } else + ilen = 0; + + aligned_dlen1 = ALIGN(dlen1, 8); + aligned_dlen2 = ALIGN(dlen2, 8); + len = aligned_dlen1 + aligned_dlen2 + ALIGN(ilen, 8) + ALIGN(plen, 8); + if (old_dir != new_dir) + len += plen; + dent = kmalloc(len, GFP_NOFS); + if (!dent) + return -ENOMEM; + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, BASEHD, len); + if (err) + goto out_free; + + /* Make new dent */ + dent->ch.node_type = UBIFS_DENT_NODE; + dent_key_init_flash(c, &dent->key, new_dir->i_ino, &new_dentry->d_name); + dent->inum = cpu_to_le64(old_inode->i_ino); + dent->type = get_dent_type(old_inode->i_mode); + dent->nlen = cpu_to_le16(new_dentry->d_name.len); + memcpy(dent->name, new_dentry->d_name.name, new_dentry->d_name.len); + dent->name[new_dentry->d_name.len] = '\0'; + zero_dent_node_unused(dent); + ubifs_prep_grp_node(c, dent, dlen1, 0); + + /* Make deletion dent */ + dent2 = (void *)dent + aligned_dlen1; + dent2->ch.node_type = UBIFS_DENT_NODE; + dent_key_init_flash(c, &dent2->key, old_dir->i_ino, + &old_dentry->d_name); + dent2->inum = 0; + dent2->type = DT_UNKNOWN; + dent2->nlen = cpu_to_le16(old_dentry->d_name.len); + memcpy(dent2->name, old_dentry->d_name.name, old_dentry->d_name.len); + dent2->name[old_dentry->d_name.len] = '\0'; + zero_dent_node_unused(dent2); + ubifs_prep_grp_node(c, dent2, dlen2, 0); + + p = (void *)dent2 + aligned_dlen2; + if (new_inode) { + pack_inode(c, p, new_inode, 0, last_reference); + p += ALIGN(ilen, 8); + } + + if (!move) + pack_inode(c, p, old_dir, 1, 0); + else { + pack_inode(c, p, old_dir, 0, 0); + p += ALIGN(plen, 8); + pack_inode(c, p, new_dir, 1, 0); + } + + if (last_reference) { + err = ubifs_add_orphan(c, new_inode->i_ino); + if (err) { + release_head(c, BASEHD); + goto out_finish; + } + } + + err = write_head(c, BASEHD, dent, len, &lnum, &offs, sync); + if (err) + goto out_release; + if (!sync) { + struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf; + + ubifs_wbuf_add_ino_nolock(wbuf, new_dir->i_ino); + ubifs_wbuf_add_ino_nolock(wbuf, old_dir->i_ino); + if (new_inode) + ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, + new_inode->i_ino); + } + release_head(c, BASEHD); + + dent_key_init(c, &key, new_dir->i_ino, &new_dentry->d_name); + err = ubifs_tnc_add_nm(c, &key, lnum, offs, dlen1, &new_dentry->d_name); + if (err) + goto out_ro; + + err = ubifs_add_dirt(c, lnum, dlen2); + if (err) + goto out_ro; + + dent_key_init(c, &key, old_dir->i_ino, &old_dentry->d_name); + err = ubifs_tnc_remove_nm(c, &key, &old_dentry->d_name); + if (err) + goto out_ro; + + offs += aligned_dlen1 + aligned_dlen2; + if (new_inode) { + ino_key_init(c, &key, new_inode->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs, ilen); + if (err) + goto out_ro; + offs += ALIGN(ilen, 8); + } + + ino_key_init(c, &key, old_dir->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs, plen); + if (err) + goto out_ro; + + if (old_dir != new_dir) { + offs += ALIGN(plen, 8); + ino_key_init(c, &key, new_dir->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs, plen); + if (err) + goto out_ro; + } + + finish_reservation(c); + if (new_inode) { + mark_inode_clean(c, new_ui); + spin_lock(&new_ui->ui_lock); + new_ui->synced_i_size = new_ui->ui_size; + spin_unlock(&new_ui->ui_lock); + } + mark_inode_clean(c, ubifs_inode(old_dir)); + if (move) + mark_inode_clean(c, ubifs_inode(new_dir)); + kfree(dent); + return 0; + +out_release: + release_head(c, BASEHD); +out_ro: + ubifs_ro_mode(c, err); + if (last_reference) + ubifs_delete_orphan(c, new_inode->i_ino); +out_finish: + finish_reservation(c); +out_free: + kfree(dent); + return err; +} + +/** + * recomp_data_node - re-compress a truncated data node. + * @dn: data node to re-compress + * @new_len: new length + * + * This function is used when an inode is truncated and the last data node of + * the inode has to be re-compressed and re-written. + */ +static int recomp_data_node(struct ubifs_data_node *dn, int *new_len) +{ + void *buf; + int err, len, compr_type, out_len; + + out_len = le32_to_cpu(dn->size); + buf = kmalloc(out_len * WORST_COMPR_FACTOR, GFP_NOFS); + if (!buf) + return -ENOMEM; + + len = le32_to_cpu(dn->ch.len) - UBIFS_DATA_NODE_SZ; + compr_type = le16_to_cpu(dn->compr_type); + err = ubifs_decompress(&dn->data, len, buf, &out_len, compr_type); + if (err) + goto out; + + ubifs_compress(buf, *new_len, &dn->data, &out_len, &compr_type); + ubifs_assert(out_len <= UBIFS_BLOCK_SIZE); + dn->compr_type = cpu_to_le16(compr_type); + dn->size = cpu_to_le32(*new_len); + *new_len = UBIFS_DATA_NODE_SZ + out_len; +out: + kfree(buf); + return err; +} + +/** + * ubifs_jnl_truncate - update the journal for a truncation. + * @c: UBIFS file-system description object + * @inode: inode to truncate + * @old_size: old size + * @new_size: new size + * + * When the size of a file decreases due to truncation, a truncation node is + * written, the journal tree is updated, and the last data block is re-written + * if it has been affected. The inode is also updated in order to synchronize + * the new inode size. + * + * This function marks the inode as clean and returns zero on success. In case + * of failure, a negative error code is returned. + */ +int ubifs_jnl_truncate(struct ubifs_info *c, const struct inode *inode, + loff_t old_size, loff_t new_size) +{ + union ubifs_key key, to_key; + struct ubifs_ino_node *ino; + struct ubifs_trun_node *trun; + struct ubifs_data_node *uninitialized_var(dn); + int err, dlen, len, lnum, offs, bit, sz, sync = IS_SYNC(inode); + struct ubifs_inode *ui = ubifs_inode(inode); + ino_t inum = inode->i_ino; + unsigned int blk; + + dbg_jnl("ino %lu, size %lld -> %lld", inum, old_size, new_size); + ubifs_assert(!ui->data_len); + ubifs_assert(S_ISREG(inode->i_mode)); + ubifs_assert(mutex_is_locked(&ui->ui_mutex)); + + sz = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ + + UBIFS_MAX_DATA_NODE_SZ * WORST_COMPR_FACTOR; + ino = kmalloc(sz, GFP_NOFS); + if (!ino) + return -ENOMEM; + + trun = (void *)ino + UBIFS_INO_NODE_SZ; + trun->ch.node_type = UBIFS_TRUN_NODE; + trun->inum = cpu_to_le32(inum); + trun->old_size = cpu_to_le64(old_size); + trun->new_size = cpu_to_le64(new_size); + zero_trun_node_unused(trun); + + dlen = new_size & (UBIFS_BLOCK_SIZE - 1); + if (dlen) { + /* Get last data block so it can be truncated */ + dn = (void *)trun + UBIFS_TRUN_NODE_SZ; + blk = new_size >> UBIFS_BLOCK_SHIFT; + data_key_init(c, &key, inum, blk); + dbg_jnl("last block key %s", DBGKEY(&key)); + err = ubifs_tnc_lookup(c, &key, dn); + if (err == -ENOENT) + dlen = 0; /* Not found (so it is a hole) */ + else if (err) + goto out_free; + else { + if (le32_to_cpu(dn->size) <= dlen) + dlen = 0; /* Nothing to do */ + else { + int compr_type = le16_to_cpu(dn->compr_type); + + if (compr_type != UBIFS_COMPR_NONE) { + err = recomp_data_node(dn, &dlen); + if (err) + goto out_free; + } else { + dn->size = cpu_to_le32(dlen); + dlen += UBIFS_DATA_NODE_SZ; + } + zero_data_node_unused(dn); + } + } + } + + /* Must make reservation before allocating sequence numbers */ + len = UBIFS_TRUN_NODE_SZ + UBIFS_INO_NODE_SZ; + if (dlen) + len += dlen; + err = make_reservation(c, BASEHD, len); + if (err) + goto out_free; + + pack_inode(c, ino, inode, 0, 0); + ubifs_prep_grp_node(c, trun, UBIFS_TRUN_NODE_SZ, dlen ? 0 : 1); + if (dlen) + ubifs_prep_grp_node(c, dn, dlen, 1); + + err = write_head(c, BASEHD, ino, len, &lnum, &offs, sync); + if (err) + goto out_release; + if (!sync) + ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, inum); + release_head(c, BASEHD); + + if (dlen) { + sz = offs + UBIFS_INO_NODE_SZ + UBIFS_TRUN_NODE_SZ; + err = ubifs_tnc_add(c, &key, lnum, sz, dlen); + if (err) + goto out_ro; + } + + ino_key_init(c, &key, inum); + err = ubifs_tnc_add(c, &key, lnum, offs, UBIFS_INO_NODE_SZ); + if (err) + goto out_ro; + + err = ubifs_add_dirt(c, lnum, UBIFS_TRUN_NODE_SZ); + if (err) + goto out_ro; + + bit = new_size & (UBIFS_BLOCK_SIZE - 1); + blk = (new_size >> UBIFS_BLOCK_SHIFT) + (bit ? 1 : 0); + data_key_init(c, &key, inum, blk); + + bit = old_size & (UBIFS_BLOCK_SIZE - 1); + blk = (old_size >> UBIFS_BLOCK_SHIFT) - (bit ? 0: 1); + data_key_init(c, &to_key, inum, blk); + + err = ubifs_tnc_remove_range(c, &key, &to_key); + if (err) + goto out_ro; + + finish_reservation(c); + spin_lock(&ui->ui_lock); + ui->synced_i_size = ui->ui_size; + spin_unlock(&ui->ui_lock); + mark_inode_clean(c, ui); + kfree(ino); + return 0; + +out_release: + release_head(c, BASEHD); +out_ro: + ubifs_ro_mode(c, err); + finish_reservation(c); +out_free: + kfree(ino); + return err; +} + +#ifdef CONFIG_UBIFS_FS_XATTR + +/** + * ubifs_jnl_delete_xattr - delete an extended attribute. + * @c: UBIFS file-system description object + * @host: host inode + * @inode: extended attribute inode + * @nm: extended attribute entry name + * + * This function delete an extended attribute which is very similar to + * un-linking regular files - it writes a deletion xentry, a deletion inode and + * updates the target inode. Returns zero in case of success and a negative + * error code in case of failure. + */ +int ubifs_jnl_delete_xattr(struct ubifs_info *c, const struct inode *host, + const struct inode *inode, const struct qstr *nm) +{ + int err, xlen, hlen, len, lnum, xent_offs, aligned_xlen; + struct ubifs_dent_node *xent; + struct ubifs_ino_node *ino; + union ubifs_key xent_key, key1, key2; + int sync = IS_DIRSYNC(host); + struct ubifs_inode *host_ui = ubifs_inode(host); + + dbg_jnl("host %lu, xattr ino %lu, name '%s', data len %d", + host->i_ino, inode->i_ino, nm->name, + ubifs_inode(inode)->data_len); + ubifs_assert(inode->i_nlink == 0); + ubifs_assert(mutex_is_locked(&host_ui->ui_mutex)); + + /* + * Since we are deleting the inode, we do not bother to attach any data + * to it and assume its length is %UBIFS_INO_NODE_SZ. + */ + xlen = UBIFS_DENT_NODE_SZ + nm->len + 1; + aligned_xlen = ALIGN(xlen, 8); + hlen = host_ui->data_len + UBIFS_INO_NODE_SZ; + len = aligned_xlen + UBIFS_INO_NODE_SZ + ALIGN(hlen, 8); + + xent = kmalloc(len, GFP_NOFS); + if (!xent) + return -ENOMEM; + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, BASEHD, len); + if (err) { + kfree(xent); + return err; + } + + xent->ch.node_type = UBIFS_XENT_NODE; + xent_key_init(c, &xent_key, host->i_ino, nm); + key_write(c, &xent_key, xent->key); + xent->inum = 0; + xent->type = get_dent_type(inode->i_mode); + xent->nlen = cpu_to_le16(nm->len); + memcpy(xent->name, nm->name, nm->len); + xent->name[nm->len] = '\0'; + zero_dent_node_unused(xent); + ubifs_prep_grp_node(c, xent, xlen, 0); + + ino = (void *)xent + aligned_xlen; + pack_inode(c, ino, inode, 0, 1); + ino = (void *)ino + UBIFS_INO_NODE_SZ; + pack_inode(c, ino, host, 1, 0); + + err = write_head(c, BASEHD, xent, len, &lnum, &xent_offs, sync); + if (!sync && !err) + ubifs_wbuf_add_ino_nolock(&c->jheads[BASEHD].wbuf, host->i_ino); + release_head(c, BASEHD); + kfree(xent); + if (err) + goto out_ro; + + /* Remove the extended attribute entry from TNC */ + err = ubifs_tnc_remove_nm(c, &xent_key, nm); + if (err) + goto out_ro; + err = ubifs_add_dirt(c, lnum, xlen); + if (err) + goto out_ro; + + /* + * Remove all nodes belonging to the extended attribute inode from TNC. + * Well, there actually must be only one node - the inode itself. + */ + lowest_ino_key(c, &key1, inode->i_ino); + highest_ino_key(c, &key2, inode->i_ino); + err = ubifs_tnc_remove_range(c, &key1, &key2); + if (err) + goto out_ro; + err = ubifs_add_dirt(c, lnum, UBIFS_INO_NODE_SZ); + if (err) + goto out_ro; + + /* And update TNC with the new host inode position */ + ino_key_init(c, &key1, host->i_ino); + err = ubifs_tnc_add(c, &key1, lnum, xent_offs + len - hlen, hlen); + if (err) + goto out_ro; + + finish_reservation(c); + spin_lock(&host_ui->ui_lock); + host_ui->synced_i_size = host_ui->ui_size; + spin_unlock(&host_ui->ui_lock); + mark_inode_clean(c, host_ui); + return 0; + +out_ro: + ubifs_ro_mode(c, err); + finish_reservation(c); + return err; +} + +/** + * ubifs_jnl_change_xattr - change an extended attribute. + * @c: UBIFS file-system description object + * @inode: extended attribute inode + * @host: host inode + * + * This function writes the updated version of an extended attribute inode and + * the host inode tho the journal (to the base head). The host inode is written + * after the extended attribute inode in order to guarantee that the extended + * attribute will be flushed when the inode is synchronized by 'fsync()' and + * consequently, the write-buffer is synchronized. This function returns zero + * in case of success and a negative error code in case of failure. + */ +int ubifs_jnl_change_xattr(struct ubifs_info *c, const struct inode *inode, + const struct inode *host) +{ + int err, len1, len2, aligned_len, aligned_len1, lnum, offs; + struct ubifs_inode *host_ui = ubifs_inode(inode); + struct ubifs_ino_node *ino; + union ubifs_key key; + int sync = IS_DIRSYNC(host); + + dbg_jnl("ino %lu, ino %lu", host->i_ino, inode->i_ino); + ubifs_assert(host->i_nlink > 0); + ubifs_assert(inode->i_nlink > 0); + ubifs_assert(mutex_is_locked(&host_ui->ui_mutex)); + + len1 = UBIFS_INO_NODE_SZ + host_ui->data_len; + len2 = UBIFS_INO_NODE_SZ + ubifs_inode(inode)->data_len; + aligned_len1 = ALIGN(len1, 8); + aligned_len = aligned_len1 + ALIGN(len2, 8); + + ino = kmalloc(aligned_len, GFP_NOFS); + if (!ino) + return -ENOMEM; + + /* Make reservation before allocating sequence numbers */ + err = make_reservation(c, BASEHD, aligned_len); + if (err) + goto out_free; + + pack_inode(c, ino, host, 0, 0); + pack_inode(c, (void *)ino + aligned_len1, inode, 1, 0); + + err = write_head(c, BASEHD, ino, aligned_len, &lnum, &offs, 0); + if (!sync && !err) { + struct ubifs_wbuf *wbuf = &c->jheads[BASEHD].wbuf; + + ubifs_wbuf_add_ino_nolock(wbuf, host->i_ino); + ubifs_wbuf_add_ino_nolock(wbuf, inode->i_ino); + } + release_head(c, BASEHD); + if (err) + goto out_ro; + + ino_key_init(c, &key, host->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs, len1); + if (err) + goto out_ro; + + ino_key_init(c, &key, inode->i_ino); + err = ubifs_tnc_add(c, &key, lnum, offs + aligned_len1, len2); + if (err) + goto out_ro; + + finish_reservation(c); + spin_lock(&host_ui->ui_lock); + host_ui->synced_i_size = host_ui->ui_size; + spin_unlock(&host_ui->ui_lock); + mark_inode_clean(c, host_ui); + kfree(ino); + return 0; + +out_ro: + ubifs_ro_mode(c, err); + finish_reservation(c); +out_free: + kfree(ino); + return err; +} + +#endif /* CONFIG_UBIFS_FS_XATTR */ |