/*
   *   Copyright (C) International Business Machines Corp., 2000-2004
   *   Portions Copyright (C) Christoph Hellwig, 2001-2002
   *
   *   This program is free software;  you can redistribute it and/or modify
   *   it under the terms of the GNU General Public License as published by

   *   the Free Software Foundation; either version 2 of the License, or

   *   (at your option) any later version.

   *

   *   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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
   */
  #ifndef	_H_JFS_LOGMGR
  #define _H_JFS_LOGMGR
  
  #include "jfs_filsys.h"
  #include "jfs_lock.h"
  
  /*
   *	log manager configuration parameters
   */
  
  /* log page size */
  #define	LOGPSIZE	4096
  #define	L2LOGPSIZE	12
  
  #define LOGPAGES	16	/* Log pages per mounted file system */
  
  /*
   *	log logical volume
   *

   * a log is used to make the commit operation on journalled

   * files within the same logical volume group atomic.
   * a log is implemented with a logical volume.

   * there is one log per logical volume group.

   *
   * block 0 of the log logical volume is not used (ipl etc).
   * block 1 contains a log "superblock" and is used by logFormat(),

   * lmLogInit(), lmLogShutdown(), and logRedo() to record status
   * of the log but is not otherwise used during normal processing.

   * blocks 2 - (N-1) are used to contain log records.
   *

   * when a volume group is varied-on-line, logRedo() must have
   * been executed before the file systems (logical volumes) in

   * the volume group can be mounted.
   */
  /*
   *	log superblock (block 1 of logical volume)
   */
  #define	LOGSUPER_B	1
  #define	LOGSTART_B	2
  
  #define	LOGMAGIC	0x87654321
  #define	LOGVERSION	1
  
  #define MAX_ACTIVE	128	/* Max active file systems sharing log */
  
  struct logsuper {
  	__le32 magic;		/* 4: log lv identifier */
  	__le32 version;		/* 4: version number */
  	__le32 serial;		/* 4: log open/mount counter */
  	__le32 size;		/* 4: size in number of LOGPSIZE blocks */
  	__le32 bsize;		/* 4: logical block size in byte */
  	__le32 l2bsize;		/* 4: log2 of bsize */
  
  	__le32 flag;		/* 4: option */
  	__le32 state;		/* 4: state - see below */
  
  	__le32 end;		/* 4: addr of last log record set by logredo */
  	char uuid[16];		/* 16: 128-bit journal uuid */
  	char label[16];		/* 16: journal label */
  	struct {
  		char uuid[16];
  	} active[MAX_ACTIVE];	/* 2048: active file systems list */
  };
  
  #define NULL_UUID "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"
  
  /* log flag: commit option (see jfs_filsys.h) */
  
  /* log state */
  #define	LOGMOUNT	0	/* log mounted by lmLogInit() */
  #define LOGREDONE	1	/* log shutdown by lmLogShutdown().
  				 * log redo completed by logredo().
  				 */
  #define LOGWRAP		2	/* log wrapped */
  #define LOGREADERR	3	/* log read error detected in logredo() */
  
  
  /*
   *	log logical page
   *
   * (this comment should be rewritten !)

   * the header and trailer structures (h,t) will normally have

   * the same page and eor value.

   * An exception to this occurs when a complete page write is not

   * accomplished on a power failure. Since the hardware may "split write"

   * sectors in the page, any out of order sequence may occur during powerfail

   * and needs to be recognized during log replay.  The xor value is
   * an "exclusive or" of all log words in the page up to eor.  This
   * 32 bit eor is stored with the top 16 bits in the header and the
   * bottom 16 bits in the trailer.  logredo can easily recognize pages

   * that were not completed by reconstructing this eor and checking

   * the log page.
   *

   * Previous versions of the operating system did not allow split
   * writes and detected partially written records in logredo by
   * ordering the updates to the header, trailer, and the move of data
   * into the logdata area.  The order: (1) data is moved (2) header
   * is updated (3) trailer is updated.  In logredo, when the header
   * differed from the trailer, the header and trailer were reconciled
   * as follows: if h.page != t.page they were set to the smaller of
   * the two and h.eor and t.eor set to 8 (i.e. empty page). if (only)

   * h.eor != t.eor they were set to the smaller of their two values.
   */
  struct logpage {
  	struct {		/* header */
  		__le32 page;	/* 4: log sequence page number */
  		__le16 rsrvd;	/* 2: */
  		__le16 eor;	/* 2: end-of-log offset of lasrt record write */
  	} h;
  
  	__le32 data[LOGPSIZE / 4 - 4];	/* log record area */
  
  	struct {		/* trailer */
  		__le32 page;	/* 4: normally the same as h.page */
  		__le16 rsrvd;	/* 2: */
  		__le16 eor;	/* 2: normally the same as h.eor */
  	} t;
  };
  
  #define LOGPHDRSIZE	8	/* log page header size */
  #define LOGPTLRSIZE	8	/* log page trailer size */
  
  
  /*
   *	log record
   *
   * (this comment should be rewritten !)
   * jfs uses only "after" log records (only a single writer is allowed

   * in a page, pages are written to temporary paging space if

   * if they must be written to disk before commit, and i/o is
   * scheduled for modified pages to their home location after

   * the log records containing the after values and the commit

   * record is written to the log on disk, undo discards the copy
   * in main-memory.)
   *

   * a log record consists of a data area of variable length followed by

   * a descriptor of fixed size LOGRDSIZE bytes.

   * the data area is rounded up to an integral number of 4-bytes and

   * must be no longer than LOGPSIZE.

   * the descriptor is of size of multiple of 4-bytes and aligned on a
   * 4-byte boundary.

   * records are packed one after the other in the data area of log pages.

   * (sometimes a DUMMY record is inserted so that at least one record ends

   * on every page or the longest record is placed on at most two pages).

   * the field eor in page header/trailer points to the byte following

   * the last record on a page.
   */
  
  /* log record types */
  #define LOG_COMMIT		0x8000
  #define LOG_SYNCPT		0x4000
  #define LOG_MOUNT		0x2000
  #define LOG_REDOPAGE		0x0800
  #define LOG_NOREDOPAGE		0x0080
  #define LOG_NOREDOINOEXT	0x0040
  #define LOG_UPDATEMAP		0x0008
  #define LOG_NOREDOFILE		0x0001
  
  /* REDOPAGE/NOREDOPAGE log record data type */
  #define	LOG_INODE		0x0001
  #define	LOG_XTREE		0x0002
  #define	LOG_DTREE		0x0004
  #define	LOG_BTROOT		0x0010
  #define	LOG_EA			0x0020
  #define	LOG_ACL			0x0040
  #define	LOG_DATA		0x0080
  #define	LOG_NEW			0x0100
  #define	LOG_EXTEND		0x0200
  #define LOG_RELOCATE		0x0400
  #define LOG_DIR_XTREE		0x0800	/* Xtree is in directory inode */
  
  /* UPDATEMAP log record descriptor type */
  #define	LOG_ALLOCXADLIST	0x0080
  #define	LOG_ALLOCPXDLIST	0x0040
  #define	LOG_ALLOCXAD		0x0020
  #define	LOG_ALLOCPXD		0x0010
  #define	LOG_FREEXADLIST		0x0008
  #define	LOG_FREEPXDLIST		0x0004
  #define	LOG_FREEXAD		0x0002
  #define	LOG_FREEPXD		0x0001
  
  
  struct lrd {
  	/*
  	 * type independent area
  	 */
  	__le32 logtid;		/* 4: log transaction identifier */
  	__le32 backchain;	/* 4: ptr to prev record of same transaction */
  	__le16 type;		/* 2: record type */
  	__le16 length;		/* 2: length of data in record (in byte) */
  	__le32 aggregate;	/* 4: file system lv/aggregate */
  	/* (16) */
  
  	/*
  	 * type dependent area (20)
  	 */
  	union {
  
  		/*

  		 *	COMMIT: commit

  		 *
  		 * transaction commit: no type-dependent information;
  		 */
  
  		/*

  		 *	REDOPAGE: after-image

  		 *
  		 * apply after-image;
  		 *
  		 * N.B. REDOPAGE, NOREDOPAGE, and UPDATEMAP must be same format;
  		 */
  		struct {
  			__le32 fileset;	/* 4: fileset number */
  			__le32 inode;	/* 4: inode number */
  			__le16 type;	/* 2: REDOPAGE record type */
  			__le16 l2linesize;	/* 2: log2 of line size */
  			pxd_t pxd;	/* 8: on-disk page pxd */
  		} redopage;	/* (20) */
  
  		/*

  		 *	NOREDOPAGE: the page is freed

  		 *
  		 * do not apply after-image records which precede this record
  		 * in the log with the same page block number to this page.
  		 *
  		 * N.B. REDOPAGE, NOREDOPAGE, and UPDATEMAP must be same format;
  		 */
  		struct {
  			__le32 fileset;	/* 4: fileset number */
  			__le32 inode;	/* 4: inode number */
  			__le16 type;	/* 2: NOREDOPAGE record type */
  			__le16 rsrvd;	/* 2: reserved */
  			pxd_t pxd;	/* 8: on-disk page pxd */
  		} noredopage;	/* (20) */
  
  		/*

  		 *	UPDATEMAP: update block allocation map

  		 *
  		 * either in-line PXD,
  		 * or     out-of-line  XADLIST;
  		 *
  		 * N.B. REDOPAGE, NOREDOPAGE, and UPDATEMAP must be same format;
  		 */
  		struct {
  			__le32 fileset;	/* 4: fileset number */
  			__le32 inode;	/* 4: inode number */
  			__le16 type;	/* 2: UPDATEMAP record type */
  			__le16 nxd;	/* 2: number of extents */
  			pxd_t pxd;	/* 8: pxd */
  		} updatemap;	/* (20) */
  
  		/*

  		 *	NOREDOINOEXT: the inode extent is freed

  		 *

  		 * do not apply after-image records which precede this
  		 * record in the log with the any of the 4 page block
  		 * numbers in this inode extent.
  		 *
  		 * NOTE: The fileset and pxd fields MUST remain in

  		 *       the same fields in the REDOPAGE record format.
  		 *
  		 */
  		struct {
  			__le32 fileset;	/* 4: fileset number */
  			__le32 iagnum;	/* 4: IAG number     */
  			__le32 inoext_idx;	/* 4: inode extent index */
  			pxd_t pxd;	/* 8: on-disk page pxd */
  		} noredoinoext;	/* (20) */
  
  		/*

  		 *	SYNCPT: log sync point

  		 *

  		 * replay log up to syncpt address specified;

  		 */
  		struct {
  			__le32 sync;	/* 4: syncpt address (0 = here) */
  		} syncpt;
  
  		/*

  		 *	MOUNT: file system mount

  		 *
  		 * file system mount: no type-dependent information;
  		 */
  
  		/*

  		 *	? FREEXTENT: free specified extent(s)

  		 *
  		 * free specified extent(s) from block allocation map
  		 * N.B.: nextents should be length of data/sizeof(xad_t)
  		 */
  		struct {
  			__le32 type;	/* 4: FREEXTENT record type */
  			__le32 nextent;	/* 4: number of extents */
  
  			/* data: PXD or XAD list */
  		} freextent;
  
  		/*

  		 *	? NOREDOFILE: this file is freed

  		 *
  		 * do not apply records which precede this record in the log
  		 * with the same inode number.
  		 *

  		 * NOREDOFILE must be the first to be written at commit

  		 * (last to be read in logredo()) - it prevents
  		 * replay of preceding updates of all preceding generations

  		 * of the inumber esp. the on-disk inode itself.

  		 */
  		struct {
  			__le32 fileset;	/* 4: fileset number */
  			__le32 inode;	/* 4: inode number */
  		} noredofile;
  
  		/*

  		 *	? NEWPAGE:

  		 *
  		 * metadata type dependent
  		 */
  		struct {
  			__le32 fileset;	/* 4: fileset number */
  			__le32 inode;	/* 4: inode number */
  			__le32 type;	/* 4: NEWPAGE record type */
  			pxd_t pxd;	/* 8: on-disk page pxd */
  		} newpage;
  
  		/*

  		 *	? DUMMY: filler

  		 *
  		 * no type-dependent information
  		 */
  	} log;
  };					/* (36) */
  
  #define	LOGRDSIZE	(sizeof(struct lrd))
  
  /*
   *	line vector descriptor
   */
  struct lvd {
  	__le16 offset;
  	__le16 length;
  };
  
  
  /*
   *	log logical volume
   */
  struct jfs_log {
  
  	struct list_head sb_list;/*  This is used to sync metadata
  				 *    before writing syncpt.
  				 */
  	struct list_head journal_list; /* Global list */
  	struct block_device *bdev; /* 4: log lv pointer */
  	int serial;		/* 4: log mount serial number */
  
  	s64 base;		/* @8: log extent address (inline log ) */
  	int size;		/* 4: log size in log page (in page) */
  	int l2bsize;		/* 4: log2 of bsize */

  	unsigned long flag;	/* 4: flag */

  
  	struct lbuf *lbuf_free;	/* 4: free lbufs */
  	wait_queue_head_t free_wait;	/* 4: */
  
  	/* log write */
  	int logtid;		/* 4: log tid */
  	int page;		/* 4: page number of eol page */
  	int eor;		/* 4: eor of last record in eol page */
  	struct lbuf *bp;	/* 4: current log page buffer */

  	struct mutex loglock;	/* 4: log write serialization lock */

  
  	/* syncpt */
  	int nextsync;		/* 4: bytes to write before next syncpt */
  	int active;		/* 4: */
  	wait_queue_head_t syncwait;	/* 4: */
  
  	/* commit */
  	uint cflag;		/* 4: */
  	struct list_head cqueue; /* FIFO commit queue */
  	struct tblock *flush_tblk; /* tblk we're waiting on for flush */
  	int gcrtc;		/* 4: GC_READY transaction count */
  	struct tblock *gclrt;	/* 4: latest GC_READY transaction */
  	spinlock_t gclock;	/* 4: group commit lock */
  	int logsize;		/* 4: log data area size in byte */
  	int lsn;		/* 4: end-of-log */
  	int clsn;		/* 4: clsn */
  	int syncpt;		/* 4: addr of last syncpt record */
  	int sync;		/* 4: addr from last logsync() */
  	struct list_head synclist;	/* 8: logsynclist anchor */
  	spinlock_t synclock;	/* 4: synclist lock */
  	struct lbuf *wqueue;	/* 4: log pageout queue */
  	int count;		/* 4: count */
  	char uuid[16];		/* 16: 128-bit uuid of log device */
  
  	int no_integrity;	/* 3: flag to disable journaling to disk */
  };
  
  /*
   * Log flag
   */
  #define log_INLINELOG	1
  #define log_SYNCBARRIER	2
  #define log_QUIESCE	3
  #define log_FLUSH	4
  
  /*
   * group commit flag
   */
  /* jfs_log */
  #define logGC_PAGEOUT	0x00000001
  
  /* tblock/lbuf */
  #define tblkGC_QUEUE		0x0001
  #define tblkGC_READY		0x0002
  #define tblkGC_COMMIT		0x0004
  #define tblkGC_COMMITTED	0x0008
  #define tblkGC_EOP		0x0010
  #define tblkGC_FREE		0x0020
  #define tblkGC_LEADER		0x0040
  #define tblkGC_ERROR		0x0080
  #define tblkGC_LAZY		0x0100	// D230860
  #define tblkGC_UNLOCKED		0x0200	// D230860
  
  /*
   *		log cache buffer header
   */
  struct lbuf {
  	struct jfs_log *l_log;	/* 4: log associated with buffer */
  
  	/*
  	 * data buffer base area
  	 */
  	uint l_flag;		/* 4: pageout control flags */
  
  	struct lbuf *l_wqnext;	/* 4: write queue link */
  	struct lbuf *l_freelist;	/* 4: freelistlink */
  
  	int l_pn;		/* 4: log page number */
  	int l_eor;		/* 4: log record eor */
  	int l_ceor;		/* 4: committed log record eor */
  
  	s64 l_blkno;		/* 8: log page block number */
  	caddr_t l_ldata;	/* 4: data page */

  	struct page *l_page;	/* The page itself */

  	uint l_offset;		/* Offset of l_ldata within the page */

  
  	wait_queue_head_t l_ioevent;	/* 4: i/o done event */

  };
  
  /* Reuse l_freelist for redrive list */
  #define l_redrive_next l_freelist
  
  /*
   *	logsynclist block
   *
   * common logsyncblk prefix for jbuf_t and tblock
   */
  struct logsyncblk {
  	u16 xflag;		/* flags */
  	u16 flag;		/* only meaninful in tblock */
  	lid_t lid;		/* lock id */
  	s32 lsn;		/* log sequence number */
  	struct list_head synclist;	/* log sync list link */
  };
  
  /*
   *	logsynclist serialization (per log)
   */
  
  #define LOGSYNC_LOCK_INIT(log) spin_lock_init(&(log)->synclock)

  #define LOGSYNC_LOCK(log, flags) spin_lock_irqsave(&(log)->synclock, flags)
  #define LOGSYNC_UNLOCK(log, flags) \
  	spin_unlock_irqrestore(&(log)->synclock, flags)

  
  /* compute the difference in bytes of lsn from sync point */
  #define logdiff(diff, lsn, log)\
  {\
  	diff = (lsn) - (log)->syncpt;\
  	if (diff < 0)\
  		diff += (log)->logsize;\
  }
  
  extern int lmLogOpen(struct super_block *sb);
  extern int lmLogClose(struct super_block *sb);
  extern int lmLogShutdown(struct jfs_log * log);
  extern int lmLogInit(struct jfs_log * log);
  extern int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize);

  extern int lmGroupCommit(struct jfs_log *, struct tblock *);
  extern int jfsIOWait(void *);

  extern void jfs_flush_journal(struct jfs_log * log, int wait);

  extern void jfs_syncpt(struct jfs_log *log, int hard_sync);

  
  #endif				/* _H_JFS_LOGMGR */