C++ JFS_SBI函数代码示例

/*
 * NAME:	jfs_mount_rw(sb, remount)
 *
 * FUNCTION:	Completes read-write mount, or remounts read-only volume
 *		as read-write
 */
int jfs_mount_rw(struct super_block *sb, int remount)
{
	struct jfs_sb_info *sbi = JFS_SBI(sb);  
	struct jfs_log *log;
	int rc;

	/*
	 * If we are re-mounting a previously read-only volume, we want to
	 * re-read the inode and block maps, since fsck.jfs may have updated
	 * them.
	 */
	if (remount) {
		if (chkSuper(sb) || (sbi->state != FM_CLEAN))
			return -EINVAL;

		truncate_inode_pages(sbi->ipimap->i_mapping, 0);
		truncate_inode_pages(sbi->ipbmap->i_mapping, 0);
		diUnmount(sbi->ipimap, 1);
		if ((rc = diMount(sbi->ipimap))) {
			jfs_err("jfs_mount_rw: diMount failed!");
			return rc;
		}

		dbUnmount(sbi->ipbmap, 1);
		if ((rc = dbMount(sbi->ipbmap))) {
			jfs_err("jfs_mount_rw: dbMount failed!");
			return rc;
		}
	}

	/*
	 * open/initialize log
	 */
	if ((rc = lmLogOpen(sb, &log)))
		return rc;

	JFS_SBI(sb)->log = log;

	/*
	 * update file system superblock;
	 */
	if ((rc = updateSuper(sb, FM_MOUNT))) {
		jfs_err("jfs_mount: updateSuper failed w/rc = %d", rc);
		lmLogClose(sb, log);
		JFS_SBI(sb)->log = 0;
		return rc;
	}

	/*
	 * write MOUNT log record of the file system
	 */
	logMOUNT(sb);

	return rc;
}

static struct dentry *jfs_lookup(struct inode *dip, struct dentry *dentry, struct nameidata *nd)
{
	struct btstack btstack;
	ino_t inum;
	struct inode *ip;
	struct component_name key;
	const char *name = dentry->d_name.name;
	int len = dentry->d_name.len;
	int rc;

	jfs_info("jfs_lookup: name = %s", name);


	if ((name[0] == '.') && (len == 1))
		inum = dip->i_ino;
	else if (strcmp(name, "..") == 0)
		inum = PARENT(dip);
	else {
		if ((rc = get_UCSname(&key, dentry)))
			return ERR_PTR(rc);
		rc = dtSearch(dip, &key, &inum, &btstack, JFS_LOOKUP);
		free_UCSname(&key);
		if (rc == -ENOENT) {
			d_add(dentry, NULL);
			return ERR_PTR(0);
		} else if (rc) {
			jfs_err("jfs_lookup: dtSearch returned %d", rc);
			return ERR_PTR(rc);
		}
	}

	ip = iget(dip->i_sb, inum);
	if (ip == NULL || is_bad_inode(ip)) {
		jfs_err("jfs_lookup: iget failed on inum %d", (uint) inum);
		if (ip)
			iput(ip);
		return ERR_PTR(-EACCES);
	}

	if (JFS_SBI(dip->i_sb)->mntflag & JFS_OS2)
		dentry->d_op = &jfs_ci_dentry_operations;

	dentry = d_splice_alias(ip, dentry);

	if (dentry && (JFS_SBI(dip->i_sb)->mntflag & JFS_OS2))
		dentry->d_op = &jfs_ci_dentry_operations;

	return dentry;
}

void jfs_clear_inode(struct inode *inode)
{
	struct jfs_inode_info *ji = JFS_IP(inode);

	if (is_bad_inode(inode))
		/*
		 * We free the fs-dependent structure before making the
		 * inode bad
		 */
		return;

	jfs_info("jfs_clear_inode called ip = 0x%p", inode);

	if (ji->active_ag != -1) {
		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
		atomic_dec(&bmap->db_active[ji->active_ag]);
	}

	ASSERT(list_empty(&ji->anon_inode_list));

	if (ji->atlhead) {
		jfs_err("jfs_clear_inode: inode %p has anonymous tlocks",
			inode);
		jfs_err("i_state = 0x%lx, cflag = 0x%lx", inode->i_state,
			ji->cflag);
	}

	free_jfs_inode(inode);
}

static int jfs_open(struct inode *inode, struct file *file)
{
	int rc;

	if ((rc = dquot_file_open(inode, file)))
		return rc;

	/*
	 * We attempt to allow only one "active" file open per aggregate
	 * group.  Otherwise, appending to files in parallel can cause
	 * fragmentation within the files.
	 *
	 * If the file is empty, it was probably just created and going
	 * to be written to.  If it has a size, we'll hold off until the
	 * file is actually grown.
	 */
	if (S_ISREG(inode->i_mode) && file->f_mode & FMODE_WRITE &&
	    (inode->i_size == 0)) {
		struct jfs_inode_info *ji = JFS_IP(inode);
		spin_lock_irq(&ji->ag_lock);
		if (ji->active_ag == -1) {
			struct jfs_sb_info *jfs_sb = JFS_SBI(inode->i_sb);
			ji->active_ag = BLKTOAG(addressPXD(&ji->ixpxd), jfs_sb);
			atomic_inc( &jfs_sb->bmap->db_active[ji->active_ag]);
		}
		spin_unlock_irq(&ji->ag_lock);
	}

	return 0;
}

int jfs_umount_rw(struct super_block *sb)
{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct jfs_log *log = sbi->log;

	if (!log)
		return 0;

	/*
	 * close log: 
	 *
	 * remove file system from log active file system list.
	 */
	jfs_flush_journal(log, 2);

	/*
	 * Make sure all metadata makes it to disk
	 */
	dbSync(sbi->ipbmap);
	diSync(sbi->ipimap);
	fsync_inode_data_buffers(sb->s_bdev->bd_inode);

	updateSuper(sb, FM_CLEAN);
	sbi->log = NULL;

	return lmLogClose(sb, log);
}

int jfs_umount_rw(struct super_block *sb)
{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct jfs_log *log = sbi->log;

	if (!log)
		return 0;

	/*
	 * close log:
	 *
	 * remove file system from log active file system list.
	 */
	jfs_flush_journal(log, 1);

	/*
	 * Make sure all metadata makes it to disk
	 */
	dbSync(sbi->ipbmap);
	diSync(sbi->ipimap);

	/*
	 * Note that we have to do this even if sync_blockdev() will
	 * do exactly the same a few instructions later:  We can't
	 * mark the superblock clean before everything is flushed to
	 * disk.
	 */
	filemap_write_and_wait(sbi->direct_inode->i_mapping);

	updateSuper(sb, FM_CLEAN);

	return lmLogClose(sb);
}

static int jfs_release(struct inode *inode, struct file *file)
{
	struct jfs_inode_info *ji = JFS_IP(inode);

	if (ji->active_ag != -1) {
		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
		atomic_dec(&bmap->db_active[ji->active_ag]);
		ji->active_ag = -1;
	}

	return 0;
}

int jfs_umount(struct super_block *sb)
{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct inode *ipbmap = sbi->ipbmap;
	struct inode *ipimap = sbi->ipimap;
	struct inode *ipaimap = sbi->ipaimap;
	struct inode *ipaimap2 = sbi->ipaimap2;
	struct jfs_log *log;
	int rc = 0;

	jfs_info("UnMount JFS: sb:0x%p", sb);

	if ((log = sbi->log))
		/*
		 * Wait for outstanding transactions to be written to log:
		 */
		jfs_flush_journal(log, 2);

	diUnmount(ipimap, 0);

	diFreeSpecial(ipimap);
	sbi->ipimap = NULL;

	ipaimap2 = sbi->ipaimap2;
	if (ipaimap2) {
		diUnmount(ipaimap2, 0);
		diFreeSpecial(ipaimap2);
		sbi->ipaimap2 = NULL;
	}

	ipaimap = sbi->ipaimap;
	diUnmount(ipaimap, 0);
	diFreeSpecial(ipaimap);
	sbi->ipaimap = NULL;

	dbUnmount(ipbmap, 0);

	diFreeSpecial(ipbmap);
	sbi->ipimap = NULL;

	filemap_write_and_wait(sbi->direct_inode->i_mapping);

	if (log) {		
		updateSuper(sb, FM_CLEAN);

		rc = lmLogClose(sb);
	}
	jfs_info("UnMount JFS Complete: rc = %d", rc);
	return rc;
}

/*
 *	updateSuper()
 *
 * update synchronously superblock if it is mounted read-write.
 */
int updateSuper(struct super_block *sb, uint state)
{
	struct jfs_superblock *j_sb;
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct buffer_head *bh;
	int rc;

	if (sbi->flag & JFS_NOINTEGRITY) {
		if (state == FM_DIRTY) {
			sbi->p_state = state;
			return 0;
		} else if (state == FM_MOUNT) {
			sbi->p_state = sbi->state;
			state = FM_DIRTY;
		} else if (state == FM_CLEAN) {
			state = sbi->p_state;
		} else
			jfs_err("updateSuper: bad state");
	} else if (sbi->state == FM_DIRTY)
		return 0;
	
	if ((rc = readSuper(sb, &bh)))
		return rc;

	j_sb = (struct jfs_superblock *)bh->b_data;

	j_sb->s_state = cpu_to_le32(state);
	sbi->state = state;

	if (state == FM_MOUNT) {
		/* record log's dev_t and mount serial number */
		j_sb->s_logdev = cpu_to_le32(sbi->log->bdev->bd_dev);
		j_sb->s_logserial = cpu_to_le32(sbi->log->serial);
	} else if (state == FM_CLEAN) {
		/*
		 * If this volume is shared with OS/2, OS/2 will need to
		 * recalculate DASD usage, since we don't deal with it.
		 */
		if (j_sb->s_flag & cpu_to_le32(JFS_DASD_ENABLED))
			j_sb->s_flag |= cpu_to_le32(JFS_DASD_PRIME);
	}

	mark_buffer_dirty(bh);
	ll_rw_block(WRITE, 1, &bh);
	wait_on_buffer(bh);
	brelse(bh);

	return 0;
}

int jfs_fsync(struct file *file, struct dentry *dentry, int datasync)
{
	struct inode *inode = dentry->d_inode;
	int rc = 0;

	if (!(inode->i_state & I_DIRTY) ||
	    (datasync && !(inode->i_state & I_DIRTY_DATASYNC))) {
		/* Make sure committed changes hit the disk */
		jfs_flush_journal(JFS_SBI(inode->i_sb)->log, 1);
		return rc;
	}

	rc |= jfs_commit_inode(inode, 1);

	return rc ? -EIO : 0;
}

int updateSuper(struct super_block *sb, uint state)
{
	struct jfs_superblock *j_sb;
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct buffer_head *bh;
	int rc;

	if (sbi->flag & JFS_NOINTEGRITY) {
		if (state == FM_DIRTY) {
			sbi->p_state = state;
			return 0;
		} else if (state == FM_MOUNT) {
			sbi->p_state = sbi->state;
			state = FM_DIRTY;
		} else if (state == FM_CLEAN) {
			state = sbi->p_state;
		} else
			jfs_err("updateSuper: bad state");
	} else if (sbi->state == FM_DIRTY)
		return 0;

	if ((rc = readSuper(sb, &bh)))
		return rc;

	j_sb = (struct jfs_superblock *)bh->b_data;

	j_sb->s_state = cpu_to_le32(state);
	sbi->state = state;

	if (state == FM_MOUNT) {
		
		j_sb->s_logdev = cpu_to_le32(new_encode_dev(sbi->log->bdev->bd_dev));
		j_sb->s_logserial = cpu_to_le32(sbi->log->serial);
	} else if (state == FM_CLEAN) {
		if (j_sb->s_flag & cpu_to_le32(JFS_DASD_ENABLED))
			j_sb->s_flag |= cpu_to_le32(JFS_DASD_PRIME);
	}

	mark_buffer_dirty(bh);
	sync_dirty_buffer(bh);
	brelse(bh);

	return 0;
}

int jfs_umount_rw(struct super_block *sb)
{
	struct jfs_sb_info *sbi = JFS_SBI(sb);
	struct jfs_log *log = sbi->log;

	if (!log)
		return 0;

	jfs_flush_journal(log, 2);

	dbSync(sbi->ipbmap);
	diSync(sbi->ipimap);

	filemap_write_and_wait(sbi->direct_inode->i_mapping);

	updateSuper(sb, FM_CLEAN);

	return lmLogClose(sb);
}

void jfs_write_inode(struct inode *inode, int wait)
{
	if (test_cflag(COMMIT_Nolink, inode))
		return;
	/*
	 * If COMMIT_DIRTY is not set, the inode isn't really dirty.
	 * It has been committed since the last change, but was still
	 * on the dirty inode list.
	 */
	 if (!test_cflag(COMMIT_Dirty, inode)) {
		/* Make sure committed changes hit the disk */
		jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
		return;
	 }

	if (jfs_commit_inode(inode, wait)) {
		jfs_err("jfs_write_inode: jfs_commit_inode failed!");
	}
}

int jfs_fsync(struct file *file, loff_t start, loff_t end, int datasync)
{
	struct inode *inode = file->f_mapping->host;
	int rc = 0;

	rc = filemap_write_and_wait_range(inode->i_mapping, start, end);
	if (rc)
		return rc;

	mutex_lock(&inode->i_mutex);
	if (!(inode->i_state & I_DIRTY_ALL) ||
	    (datasync && !(inode->i_state & I_DIRTY_DATASYNC))) {
		/* Make sure committed changes hit the disk */
		jfs_flush_journal(JFS_SBI(inode->i_sb)->log, 1);
		mutex_unlock(&inode->i_mutex);
		return rc;
	}

	rc |= jfs_commit_inode(inode, 1);
	mutex_unlock(&inode->i_mutex);

	return rc ? -EIO : 0;
}

int jfs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
	int wait = 1; /* XXX fix fsync and use wbc->sync_mode == WB_SYNC_ALL; */

	if (test_cflag(COMMIT_Nolink, inode))
		return 0;
	/*
	 * If COMMIT_DIRTY is not set, the inode isn't really dirty.
	 * It has been committed since the last change, but was still
	 * on the dirty inode list.
	 */
	 if (!test_cflag(COMMIT_Dirty, inode)) {
		/* Make sure committed changes hit the disk */
		jfs_flush_journal(JFS_SBI(inode->i_sb)->log, wait);
		return 0;
	 }

	if (jfs_commit_inode(inode, wait)) {
		jfs_err("jfs_write_inode: jfs_commit_inode failed!");
		return -EIO;
	} else
		return 0;
}