自学教程：C++ test_cflag函数代码示例

void jfs_delete_inode(struct inode *inode){	jfs_info("In jfs_delete_inode, inode = 0x%p", inode);	if (!is_bad_inode(inode))		dquot_initialize(inode);	if (!is_bad_inode(inode) &&	    (JFS_IP(inode)->fileset == FILESYSTEM_I)) {		truncate_inode_pages(&inode->i_data, 0);		if (test_cflag(COMMIT_Freewmap, inode))			jfs_free_zero_link(inode);		diFree(inode);		/*		 * Free the inode from the quota allocation.		 */		dquot_initialize(inode);		dquot_free_inode(inode);		dquot_drop(inode);	}	clear_inode(inode);}

void jfs_evict_inode(struct inode *inode){	jfs_info("In jfs_evict_inode, inode = 0x%p", inode);	if (!inode->i_nlink && !is_bad_inode(inode)) {		dquot_initialize(inode);		if (JFS_IP(inode)->fileset == FILESYSTEM_I) {			truncate_inode_pages(&inode->i_data, 0);			if (test_cflag(COMMIT_Freewmap, inode))				jfs_free_zero_link(inode);			diFree(inode);			/*			 * Free the inode from the quota allocation.			 */			dquot_initialize(inode);			dquot_free_inode(inode);		}	} else {		truncate_inode_pages(&inode->i_data, 0);	}	end_writeback(inode);	dquot_drop(inode);}

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!");	}}

void jfs_delete_inode(struct inode *inode){	jfs_info("In jfs_delete_inode, inode = 0x%p", inode);	if (test_cflag(COMMIT_Freewmap, inode))		freeZeroLink(inode);	diFree(inode);	clear_inode(inode);}

/* * Workhorse of both fsync & write_inode */int jfs_commit_inode(struct inode *inode, int wait){	int rc = 0;	tid_t tid;	static int noisy = 5;	jfs_info("In jfs_commit_inode, inode = 0x%p", inode);	/*	 * Don't commit if inode has been committed since last being	 * marked dirty, or if it has been deleted.	 */	if (inode->i_nlink == 0 || !test_cflag(COMMIT_Dirty, inode))		return 0;	if (isReadOnly(inode)) {		/* kernel allows writes to devices on read-only		 * partitions and may think inode is dirty		 */		if (!special_file(inode->i_mode) && noisy) {			jfs_err("jfs_commit_inode(0x%p) called on "				   "read-only volume", inode);			jfs_err("Is remount racy?");			noisy--;		}		return 0;	}	tid = txBegin(inode->i_sb, COMMIT_INODE);	mutex_lock(&JFS_IP(inode)->commit_mutex);	/*	 * Retest inode state after taking commit_mutex	 */	if (inode->i_nlink && test_cflag(COMMIT_Dirty, inode))		rc = txCommit(tid, 1, &inode, wait ? COMMIT_SYNC : 0);	txEnd(tid);	mutex_unlock(&JFS_IP(inode)->commit_mutex);	return rc;}

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;}

void jfs_delete_inode(struct inode *inode){	jfs_info("In jfs_delete_inode, inode = 0x%p", inode);	if (test_cflag(COMMIT_Freewmap, inode))		freeZeroLink(inode);	diFree(inode);	/*	 * Free the inode from the quota allocation.	 */	DQUOT_INIT(inode);	DQUOT_FREE_INODE(inode);	DQUOT_DROP(inode);	clear_inode(inode);}

/* * Guts of jfs_truncate.  Called with locks already held.  Can be called * with directory for truncating directory index table. */void jfs_truncate_nolock(struct inode *ip, loff_t length){	loff_t newsize;	tid_t tid;	ASSERT(length >= 0);	if (test_cflag(COMMIT_Nolink, ip)) {		xtTruncate(0, ip, length, COMMIT_WMAP);		return;	}	do {		tid = txBegin(ip->i_sb, 0);		/*		 * The commit_mutex cannot be taken before txBegin.		 * txBegin may block and there is a chance the inode		 * could be marked dirty and need to be committed		 * before txBegin unblocks		 */		mutex_lock(&JFS_IP(ip)->commit_mutex);		newsize = xtTruncate(tid, ip, length,				     COMMIT_TRUNCATE | COMMIT_PWMAP);		if (newsize < 0) {			txEnd(tid);			mutex_unlock(&JFS_IP(ip)->commit_mutex);			break;		}		ip->i_mtime = ip->i_ctime = CURRENT_TIME;		mark_inode_dirty(ip);		txCommit(tid, 1, &ip, 0);		txEnd(tid);		mutex_unlock(&JFS_IP(ip)->commit_mutex);	} while (newsize > length);	/* Truncate isn't always atomic */}

/* * NAME:	jfs_unlink(dip, dentry) * * FUNCTION:	remove a link to object <vp> named by <name> *		from parent directory <dvp> * * PARAMETER:	dip	- inode of parent directory *		dentry	- dentry of object to be removed * * RETURN:	errors from subroutines * * note: * temporary file: if one or more processes have the file open * when the last link is removed, the link will be removed before * unlink() returns, but the removal of the file contents will be * postponed until all references to the files are closed. * * JFS does NOT support unlink() on directories. * */static int jfs_unlink(struct inode *dip, struct dentry *dentry){    int rc;    tid_t tid;		/* transaction id */    struct inode *ip = dentry->d_inode;    ino_t ino;    struct component_name dname;	/* object name */    struct inode *iplist[2];    struct tblock *tblk;    s64 new_size = 0;    int commit_flag;    jfs_info("jfs_unlink: dip:0x%p name:%s", dip, dentry->d_name.name);    /* Init inode for quota operations. */    dquot_initialize(dip);    dquot_initialize(ip);    if ((rc = get_UCSname(&dname, dentry)))        goto out;    IWRITE_LOCK(ip, RDWRLOCK_NORMAL);    tid = txBegin(dip->i_sb, 0);    mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);    mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);    iplist[0] = dip;    iplist[1] = ip;    /*     * delete the entry of target file from parent directory     */    ino = ip->i_ino;    if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {        jfs_err("jfs_unlink: dtDelete returned %d", rc);        if (rc == -EIO)            txAbort(tid, 1);	/* Marks FS Dirty */        txEnd(tid);        mutex_unlock(&JFS_IP(ip)->commit_mutex);        mutex_unlock(&JFS_IP(dip)->commit_mutex);        IWRITE_UNLOCK(ip);        goto out1;    }    ASSERT(ip->i_nlink);    ip->i_ctime = dip->i_ctime = dip->i_mtime = CURRENT_TIME;    mark_inode_dirty(dip);    /* update target's inode */    inode_dec_link_count(ip);    /*     *	commit zero link count object     */    if (ip->i_nlink == 0) {        assert(!test_cflag(COMMIT_Nolink, ip));        /* free block resources */        if ((new_size = commitZeroLink(tid, ip)) < 0) {            txAbort(tid, 1);	/* Marks FS Dirty */            txEnd(tid);            mutex_unlock(&JFS_IP(ip)->commit_mutex);            mutex_unlock(&JFS_IP(dip)->commit_mutex);            IWRITE_UNLOCK(ip);            rc = new_size;            goto out1;        }        tblk = tid_to_tblock(tid);        tblk->xflag |= COMMIT_DELETE;        tblk->u.ip = ip;    }    /*     * Incomplete truncate of file data can     * result in timing problems unless we synchronously commit the     * transaction.     */    if (new_size)//.........这里部分代码省略.........

//.........这里部分代码省略.........    ino_t ino;    struct component_name dname;    struct inode *iplist[2];    struct tblock *tblk;    jfs_info("jfs_rmdir: dip:0x%p name:%s", dip, dentry->d_name.name);    /* Init inode for quota operations. */    dquot_initialize(dip);    dquot_initialize(ip);    /* directory must be empty to be removed */    if (!dtEmpty(ip)) {        rc = -ENOTEMPTY;        goto out;    }    if ((rc = get_UCSname(&dname, dentry))) {        goto out;    }    tid = txBegin(dip->i_sb, 0);    mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);    mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);    iplist[0] = dip;    iplist[1] = ip;    tblk = tid_to_tblock(tid);    tblk->xflag |= COMMIT_DELETE;    tblk->u.ip = ip;    /*     * delete the entry of target directory from parent directory     */    ino = ip->i_ino;    if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {        jfs_err("jfs_rmdir: dtDelete returned %d", rc);        if (rc == -EIO)            txAbort(tid, 1);        txEnd(tid);        mutex_unlock(&JFS_IP(ip)->commit_mutex);        mutex_unlock(&JFS_IP(dip)->commit_mutex);        goto out2;    }    /* update parent directory's link count corresponding     * to ".." entry of the target directory deleted     */    dip->i_ctime = dip->i_mtime = CURRENT_TIME;    inode_dec_link_count(dip);    /*     * OS/2 could have created EA and/or ACL     */    /* free EA from both persistent and working map */    if (JFS_IP(ip)->ea.flag & DXD_EXTENT) {        /* free EA pages */        txEA(tid, ip, &JFS_IP(ip)->ea, NULL);    }    JFS_IP(ip)->ea.flag = 0;    /* free ACL from both persistent and working map */    if (JFS_IP(ip)->acl.flag & DXD_EXTENT) {        /* free ACL pages */        txEA(tid, ip, &JFS_IP(ip)->acl, NULL);    }    JFS_IP(ip)->acl.flag = 0;    /* mark the target directory as deleted */    clear_nlink(ip);    mark_inode_dirty(ip);    rc = txCommit(tid, 2, &iplist[0], 0);    txEnd(tid);    mutex_unlock(&JFS_IP(ip)->commit_mutex);    mutex_unlock(&JFS_IP(dip)->commit_mutex);    /*     * Truncating the directory index table is not guaranteed.  It     * may need to be done iteratively     */    if (test_cflag(COMMIT_Stale, dip)) {        if (dip->i_size > 1)            jfs_truncate_nolock(dip, 0);        clear_cflag(COMMIT_Stale, dip);    }out2:    free_UCSname(&dname);out:    jfs_info("jfs_rmdir: rc:%d", rc);    return rc;}

//.........这里部分代码省略.........        mutex_lock_nested(&JFS_IP(old_dir)->commit_mutex,                          COMMIT_MUTEX_SECOND_PARENT);    if (new_ip) {        mutex_lock_nested(&JFS_IP(new_ip)->commit_mutex,                          COMMIT_MUTEX_VICTIM);        /*         * Change existing directory entry to new inode number         */        ino = new_ip->i_ino;        rc = dtModify(tid, new_dir, &new_dname, &ino,                      old_ip->i_ino, JFS_RENAME);        if (rc)            goto out4;        drop_nlink(new_ip);        if (S_ISDIR(new_ip->i_mode)) {            drop_nlink(new_ip);            if (new_ip->i_nlink) {                mutex_unlock(&JFS_IP(new_ip)->commit_mutex);                if (old_dir != new_dir)                    mutex_unlock(&JFS_IP(old_dir)->commit_mutex);                mutex_unlock(&JFS_IP(old_ip)->commit_mutex);                mutex_unlock(&JFS_IP(new_dir)->commit_mutex);                if (!S_ISDIR(old_ip->i_mode) && new_ip)                    IWRITE_UNLOCK(new_ip);                jfs_error(new_ip->i_sb,                          "jfs_rename: new_ip->i_nlink != 0");                return -EIO;            }            tblk = tid_to_tblock(tid);            tblk->xflag |= COMMIT_DELETE;            tblk->u.ip = new_ip;        } else if (new_ip->i_nlink == 0) {            assert(!test_cflag(COMMIT_Nolink, new_ip));            /* free block resources */            if ((new_size = commitZeroLink(tid, new_ip)) < 0) {                txAbort(tid, 1);	/* Marks FS Dirty */                rc = new_size;                goto out4;            }            tblk = tid_to_tblock(tid);            tblk->xflag |= COMMIT_DELETE;            tblk->u.ip = new_ip;        } else {            new_ip->i_ctime = CURRENT_TIME;            mark_inode_dirty(new_ip);        }    } else {        /*         * Add new directory entry         */        rc = dtSearch(new_dir, &new_dname, &ino, &btstack,                      JFS_CREATE);        if (rc) {            jfs_err("jfs_rename didn't expect dtSearch to fail "                    "w/rc = %d", rc);            goto out4;        }        ino = old_ip->i_ino;        rc = dtInsert(tid, new_dir, &new_dname, &ino, &btstack);        if (rc) {            if (rc == -EIO)                jfs_err("jfs_rename: dtInsert returned -EIO");            goto out4;        }

/* * NAME:	jfs_unlink(dip, dentry) * * FUNCTION:	remove a link to object <vp> named by <name>  *		from parent directory <dvp> * * PARAMETER:	dip 	- inode of parent directory *		dentry 	- dentry of object to be removed * * RETURN:	errors from subroutines * * note: * temporary file: if one or more processes have the file open * when the last link is removed, the link will be removed before * unlink() returns, but the removal of the file contents will be * postponed until all references to the files are closed. * * JFS does NOT support unlink() on directories. * */int jfs_unlink(struct inode *dip, struct dentry *dentry){	int rc;	tid_t tid;		/* transaction id */	struct inode *ip = dentry->d_inode;	ino_t ino;	struct component_name dname;	/* object name */	struct inode *iplist[2];	struct tblock *tblk;	s64 new_size = 0;	int commit_flag;	jFYI(1, ("jfs_unlink: dip:0x%p name:%s/n", dip, dentry->d_name.name));	if ((rc = get_UCSname(&dname, dentry, JFS_SBI(dip->i_sb)->nls_tab)))		goto out;	IWRITE_LOCK(ip);	tid = txBegin(dip->i_sb, 0);	down(&JFS_IP(dip)->commit_sem);	down(&JFS_IP(ip)->commit_sem);	iplist[0] = dip;	iplist[1] = ip;	/*	 * delete the entry of target file from parent directory	 */	ino = ip->i_ino;	if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {		jERROR(1, ("jfs_unlink: dtDelete returned %d/n", rc));		if (rc == EIO)			txAbort(tid, 1);	/* Marks FS Dirty */		txEnd(tid);		up(&JFS_IP(dip)->commit_sem);		up(&JFS_IP(ip)->commit_sem);		IWRITE_UNLOCK(ip);		goto out1;	}	ASSERT(ip->i_nlink);	ip->i_ctime = dip->i_ctime = dip->i_mtime = CURRENT_TIME;	mark_inode_dirty(dip);	/* update target's inode */	ip->i_nlink--;	mark_inode_dirty(ip);	/*	 *      commit zero link count object	 */	if (ip->i_nlink == 0) {		assert(!test_cflag(COMMIT_Nolink, ip));		/* free block resources */		if ((new_size = commitZeroLink(tid, ip)) < 0) {			txAbort(tid, 1);	/* Marks FS Dirty */			txEnd(tid);			up(&JFS_IP(dip)->commit_sem);			up(&JFS_IP(ip)->commit_sem);			IWRITE_UNLOCK(ip);			rc = -new_size;		/* We return -rc */			goto out1;		}		tblk = tid_to_tblock(tid);		tblk->xflag |= COMMIT_DELETE;		tblk->ip = ip;	}	/*	 * Incomplete truncate of file data can	 * result in timing problems unless we synchronously commit the	 * transaction.	 */	if (new_size)		commit_flag = COMMIT_SYNC;	else		commit_flag = 0;//.........这里部分代码省略.........

//.........这里部分代码省略.........	int rc;	tid_t tid;		/* transaction id */	struct inode *ip = dentry->d_inode;	ino_t ino;	struct component_name dname;	struct inode *iplist[2];	struct tblock *tblk;	jFYI(1, ("jfs_rmdir: dip:0x%p name:%s/n", dip, dentry->d_name.name));	/* directory must be empty to be removed */	if (!dtEmpty(ip)) {		rc = ENOTEMPTY;		goto out;	}	if ((rc = get_UCSname(&dname, dentry, JFS_SBI(dip->i_sb)->nls_tab))) {		goto out;	}	tid = txBegin(dip->i_sb, 0);	down(&JFS_IP(dip)->commit_sem);	down(&JFS_IP(ip)->commit_sem);	iplist[0] = dip;	iplist[1] = ip;	tblk = tid_to_tblock(tid);	tblk->xflag |= COMMIT_DELETE;	tblk->ip = ip;	/*	 * delete the entry of target directory from parent directory	 */	ino = ip->i_ino;	if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {		jERROR(1, ("jfs_rmdir: dtDelete returned %d/n", rc));		if (rc == EIO)			txAbort(tid, 1);		txEnd(tid);		up(&JFS_IP(dip)->commit_sem);		up(&JFS_IP(ip)->commit_sem);		goto out2;	}	/* update parent directory's link count corresponding	 * to ".." entry of the target directory deleted	 */	dip->i_nlink--;	dip->i_ctime = dip->i_mtime = CURRENT_TIME;	mark_inode_dirty(dip);	/*	 * OS/2 could have created EA and/or ACL	 */	/* free EA from both persistent and working map */	if (JFS_IP(ip)->ea.flag & DXD_EXTENT) {		/* free EA pages */		txEA(tid, ip, &JFS_IP(ip)->ea, NULL);	}	JFS_IP(ip)->ea.flag = 0;	/* free ACL from both persistent and working map */	if (JFS_IP(ip)->acl.flag & DXD_EXTENT) {		/* free ACL pages */		txEA(tid, ip, &JFS_IP(ip)->acl, NULL);	}	JFS_IP(ip)->acl.flag = 0;	/* mark the target directory as deleted */	ip->i_nlink = 0;	mark_inode_dirty(ip);	rc = txCommit(tid, 2, &iplist[0], 0);	txEnd(tid);	up(&JFS_IP(dip)->commit_sem);	up(&JFS_IP(ip)->commit_sem);	/*	 * Truncating the directory index table is not guaranteed.  It	 * may need to be done iteratively	 */	if (test_cflag(COMMIT_Stale, dip)) {		if (dip->i_size > 1)			jfs_truncate_nolock(dip, 0);		clear_cflag(COMMIT_Stale, dip);	}      out2:	free_UCSname(&dname);      out:	jFYI(1, ("jfs_rmdir: rc:%d/n", rc));	return -rc;}

//.........这里部分代码省略.........			goto out3;		}	} else if (new_ip)		IWRITE_LOCK(new_ip);	/*	 * The real work starts here	 */	tid = txBegin(new_dir->i_sb, 0);	down(&JFS_IP(new_dir)->commit_sem);	down(&JFS_IP(old_ip)->commit_sem);	if (old_dir != new_dir)		down(&JFS_IP(old_dir)->commit_sem);	if (new_ip) {		down(&JFS_IP(new_ip)->commit_sem);		/*		 * Change existing directory entry to new inode number		 */		ino = new_ip->i_ino;		rc = dtModify(tid, new_dir, &new_dname, &ino,			      old_ip->i_ino, JFS_RENAME);		if (rc)			goto out4;		new_ip->i_nlink--;		if (S_ISDIR(new_ip->i_mode)) {			new_ip->i_nlink--;			assert(new_ip->i_nlink == 0);			tblk = tid_to_tblock(tid);			tblk->xflag |= COMMIT_DELETE;			tblk->ip = new_ip;		} else if (new_ip->i_nlink == 0) {			assert(!test_cflag(COMMIT_Nolink, new_ip));			/* free block resources */			if ((new_size = commitZeroLink(tid, new_ip)) < 0) {				txAbort(tid, 1);	/* Marks FS Dirty */				rc = -new_size;		/* We return -rc */				goto out4;			}			tblk = tid_to_tblock(tid);			tblk->xflag |= COMMIT_DELETE;			tblk->ip = new_ip;		} else {			new_ip->i_ctime = CURRENT_TIME;			mark_inode_dirty(new_ip);		}	} else {		/*		 * Add new directory entry		 */		rc = dtSearch(new_dir, &new_dname, &ino, &btstack,			      JFS_CREATE);		if (rc) {			jERROR(1,			       ("jfs_rename didn't expect dtSearch to fail w/rc = %d/n",				rc));			goto out4;		}		ino = old_ip->i_ino;		rc = dtInsert(tid, new_dir, &new_dname, &ino, &btstack);		if (rc) {			jERROR(1,			       ("jfs_rename: dtInsert failed w/rc = %d/n",				rc));