8  *	jfs_txnmgr.c: transaction manager
11  * transaction starts with txBegin() and ends with txCommit()
24  * tlock during write()/mmap() under anonymous transaction (tid = 0):
25  * transferred (?) to transaction at commit time.
51  *	transaction management structures
84 static int nTxBlock = -1;	/* number of transaction blocks */
87 		 "Number of transaction blocks (max:65536)");
89 static int nTxLock = -1;	/* number of transaction locks */
92 		 "Number of transaction locks (max:65536)");
94 struct tblock *TxBlock;	/* transaction block table */
98 struct tlock *TxLock;	/* transaction lock table */
101  *	transaction management lock
171  *		transaction block/lock management
176  * Get a transaction lock from the free list.  If the number in use is
178  * free some anonymous transaction locks.  (TXN_LOCK must be held.)
219  * FUNCTION:	initialize transaction management structures
261 	 * initialize transaction block (tblock) table  in txInit()
263 	 * transaction id (tid) = tblock index  in txInit()
291 	 * initialize transaction lock (tlock) table  in txInit()
293 	 * transaction lock id = tlock index  in txInit()
339  * FUNCTION:	start a transaction.
344  * RETURN:	tid	- transaction id
381 		 * Don't begin transaction if we're getting starved for tlocks  in txBegin()
393 	 * allocate transaction id/block  in txBegin()
405 		/* Don't let a non-forced transaction take the last tblk */  in txBegin()
415 	 * initialize transaction  in txBegin()
445  * FUNCTION:	start an anonymous transaction.
474 	 * Don't begin transaction if we're getting starved for tlocks  in txBeginAnon()
487  * function: free specified transaction block.
503 	 * by the current transaction  in txEnd()
511 	 * otherwise, we would be left with a transaction that may have been  in txEnd()
575  * function: acquire a transaction lock on the specified <mp>
579  * return:	transaction lock id
609 	/* is page not locked by a transaction ? */  in txLock()
615 	/* is page locked by the requester transaction ? */  in txLock()
623 	 * is page locked by anonymous transaction/lock ?  in txLock()
625 	 * (page update without transaction (i.e., file write) is  in txLock()
626 	 * locked under anonymous transaction tid = 0:  in txLock()
630 	 * they are transferred to the transaction tlock list of  in txLock()
631 	 * the committing transaction of the inode)  in txLock()
638 		 * The order of the tlocks in the transaction is important  in txLock()
642 		 * transaction list  in txLock()
669 		/* insert the tlock at tail of transaction tlock list */  in txLock()
708 		/* if anonymous transaction, and buffer is on the group  in txLock()
734 	 * enqueue transaction lock to transaction/inode  in txLock()
736 	/* insert the tlock at tail of transaction tlock list */  in txLock()
746 	/* anonymous transaction:  in txLock()
753 			/* This inode's first anonymous transaction */  in txLock()
819 	 * page is being locked by another transaction:  in txLock()
859  * FUNCTION:	Release buffers associated with transaction locks, but don't
888 	 * by the current transaction  in txRelease()
985  * function: allocate a transaction lock for freed page/entry;
1019 	 * enqueue transaction lock to transaction/inode  in txMaplock()
1021 	/* insert the tlock at tail of transaction tlock list */  in txMaplock()
1031 	/* anonymous transaction:  in txMaplock()
1038 			/* This inode's first anonymous transaction */  in txMaplock()
1059  * function: allocate a transaction lock for log vector list
1092  *		transaction commit management
1128 int txCommit(tid_t tid,		/* transaction identifier */  in txCommit()
1185 	 *	acquire transaction lock on (on-disk) inodes  in txCommit()
1188 	 * acquiring transaction locks for AFTER records  in txCommit()
1192 	 * to prevent deadlock when acquiring transaction lock  in txCommit()
1225 		 * to be written before the transaction is committed and  in txCommit()
1253 		 * acquire transaction lock on on-disk inode page  in txCommit()
1261 	 *	write log records from transaction locks  in txCommit()
1280 		 * commit the transaction synchronously, so the last iput  in txCommit()
1308 	 *	- transaction is now committed -  in txCommit()
1331 	 *	free transaction locks and pageout/free pages  in txCommit()
1381 	 * write log record(s) for each tlock of transaction,  in txLog()
1751 			 * that transaction is not committed lazily.  in xtLog()
1854 			 * that transaction is not committed lazily.  in xtLog()
1893 		 * Therefore, we'll just force transaction to be committed  in xtLog()
2175  * function: synchronously write pages locked by transaction
2185 	 * reverse the order of transaction tlocks in  in txForce()
2270 	 * scan each tlock/page of transaction for block allocation/free:  in txUpdateMap()
2272 	 * for each tlock/page of transaction, update map.  in txUpdateMap()
2316 			 * transaction  in txUpdateMap()
2602 	 * free tlocks of the transaction  in txAbort()
2617 			 * transaction(s) but has not been paged, i.e.,  in txAbort()
2630 	/* caller will free the transaction block */  in txAbort()
2729 				 * Remove transaction from queue  in jfs_lazycommit()