// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) International Business Machines Corp., 2000-2004 * Portions Copyright (C) Christoph Hellwig, 2001-2002 */ /* * jfs_logmgr.c: log manager * * for related information, see transaction manager (jfs_txnmgr.c), and * recovery manager (jfs_logredo.c). * * note: for detail, RTFS. * * log buffer manager: * special purpose buffer manager supporting log i/o requirements. * per log serial pageout of logpage * queuing i/o requests and redrive i/o at iodone * maintain current logpage buffer * no caching since append only * appropriate jfs buffer cache buffers as needed * * group commit: * transactions which wrote COMMIT records in the same in-memory * log page during the pageout of previous/current log page(s) are * committed together by the pageout of the page. * * TBD lazy commit: * transactions are committed asynchronously when the log page * containing it COMMIT is paged out when it becomes full; * * serialization: * . a per log lock serialize log write. * . a per log lock serialize group commit. * . a per log lock serialize log open/close; * * TBD log integrity: * careful-write (ping-pong) of last logpage to recover from crash * in overwrite. * detection of split (out-of-order) write of physical sectors * of last logpage via timestamp at end of each sector * with its mirror data array at trailer). * * alternatives: * lsn - 64-bit monotonically increasing integer vs * 32-bit lspn and page eor. */ #include <linux/fs.h> #include <linux/blkdev.h> #include <linux/interrupt.h> #include <linux/completion.h> #include <linux/kthread.h> #include <linux/buffer_head.h> /* for sync_blockdev() */ #include <linux/bio.h> #include <linux/freezer.h> #include <linux/export.h> #include <linux/delay.h> #include <linux/mutex.h> #include <linux/seq_file.h> #include <linux/slab.h> #include "jfs_incore.h" #include "jfs_filsys.h" #include "jfs_metapage.h" #include "jfs_superblock.h" #include "jfs_txnmgr.h" #include "jfs_debug.h" /* * lbuf's ready to be redriven. Protected by log_redrive_lock (jfsIO thread) */ static struct lbuf *log_redrive_list; static DEFINE_SPINLOCK(log_redrive_lock); /* * log read/write serialization (per log) */ #define LOG_LOCK_INIT(log) … #define LOG_LOCK(log) … #define LOG_UNLOCK(log) … /* * log group commit serialization (per log) */ #define LOGGC_LOCK_INIT(log) … #define LOGGC_LOCK(log) … #define LOGGC_UNLOCK(log) … #define LOGGC_WAKEUP(tblk) … /* * log sync serialization (per log) */ #define LOGSYNC_DELTA(logsize) … #define LOGSYNC_BARRIER(logsize) … /* #define LOGSYNC_DELTA(logsize) min((logsize)/4, 256*LOGPSIZE) #define LOGSYNC_BARRIER(logsize) ((logsize)/2) */ /* * log buffer cache synchronization */ static DEFINE_SPINLOCK(jfsLCacheLock); #define LCACHE_LOCK(flags) … #define LCACHE_UNLOCK(flags) … /* * See __SLEEP_COND in jfs_locks.h */ #define LCACHE_SLEEP_COND(wq, cond, flags) … #define LCACHE_WAKEUP(event) … /* * lbuf buffer cache (lCache) control */ /* log buffer manager pageout control (cumulative, inclusive) */ #define lbmREAD … #define lbmWRITE … #define lbmRELEASE … #define lbmSYNC … #define lbmFREE … #define lbmDONE … #define lbmERROR … #define lbmGC … #define lbmDIRECT … /* * Global list of active external journals */ static LIST_HEAD(jfs_external_logs); static struct jfs_log *dummy_log; static DEFINE_MUTEX(jfs_log_mutex); /* * forward references */ static int lmWriteRecord(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd, struct tlock * tlck); static int lmNextPage(struct jfs_log * log); static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi, int activate); static int open_inline_log(struct super_block *sb); static int open_dummy_log(struct super_block *sb); static int lbmLogInit(struct jfs_log * log); static void lbmLogShutdown(struct jfs_log * log); static struct lbuf *lbmAllocate(struct jfs_log * log, int); static void lbmFree(struct lbuf * bp); static void lbmfree(struct lbuf * bp); static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp); static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag, int cant_block); static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag); static int lbmIOWait(struct lbuf * bp, int flag); static bio_end_io_t lbmIODone; static void lbmStartIO(struct lbuf * bp); static void lmGCwrite(struct jfs_log * log, int cant_block); static int lmLogSync(struct jfs_log * log, int hard_sync); /* * statistics */ #ifdef CONFIG_JFS_STATISTICS static struct lmStat { … } lmStat; #endif static void write_special_inodes(struct jfs_log *log, int (*writer)(struct address_space *)) { … } /* * NAME: lmLog() * * FUNCTION: write a log record; * * PARAMETER: * * RETURN: lsn - offset to the next log record to write (end-of-log); * -1 - error; * * note: todo: log error handler */ int lmLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd, struct tlock * tlck) { … } /* * NAME: lmWriteRecord() * * FUNCTION: move the log record to current log page * * PARAMETER: cd - commit descriptor * * RETURN: end-of-log address * * serialization: LOG_LOCK() held on entry/exit */ static int lmWriteRecord(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd, struct tlock * tlck) { … } /* * NAME: lmNextPage() * * FUNCTION: write current page and allocate next page. * * PARAMETER: log * * RETURN: 0 * * serialization: LOG_LOCK() held on entry/exit */ static int lmNextPage(struct jfs_log * log) { … } /* * NAME: lmGroupCommit() * * FUNCTION: group commit * initiate pageout of the pages with COMMIT in the order of * page number - redrive pageout of the page at the head of * pageout queue until full page has been written. * * RETURN: * * NOTE: * LOGGC_LOCK serializes log group commit queue, and * transaction blocks on the commit queue. * N.B. LOG_LOCK is NOT held during lmGroupCommit(). */ int lmGroupCommit(struct jfs_log * log, struct tblock * tblk) { … } /* * NAME: lmGCwrite() * * FUNCTION: group commit write * initiate write of log page, building a group of all transactions * with commit records on that page. * * RETURN: None * * NOTE: * LOGGC_LOCK must be held by caller. * N.B. LOG_LOCK is NOT held during lmGroupCommit(). */ static void lmGCwrite(struct jfs_log * log, int cant_write) { … } /* * NAME: lmPostGC() * * FUNCTION: group commit post-processing * Processes transactions after their commit records have been written * to disk, redriving log I/O if necessary. * * RETURN: None * * NOTE: * This routine is called a interrupt time by lbmIODone */ static void lmPostGC(struct lbuf * bp) { … } /* * NAME: lmLogSync() * * FUNCTION: write log SYNCPT record for specified log * if new sync address is available * (normally the case if sync() is executed by back-ground * process). * calculate new value of i_nextsync which determines when * this code is called again. * * PARAMETERS: log - log structure * hard_sync - 1 to force all metadata to be written * * RETURN: 0 * * serialization: LOG_LOCK() held on entry/exit */ static int lmLogSync(struct jfs_log * log, int hard_sync) { … } /* * NAME: jfs_syncpt * * FUNCTION: write log SYNCPT record for specified log * * PARAMETERS: log - log structure * hard_sync - set to 1 to force metadata to be written */ void jfs_syncpt(struct jfs_log *log, int hard_sync) { … } /* * NAME: lmLogOpen() * * FUNCTION: open the log on first open; * insert filesystem in the active list of the log. * * PARAMETER: ipmnt - file system mount inode * iplog - log inode (out) * * RETURN: * * serialization: */ int lmLogOpen(struct super_block *sb) { … } static int open_inline_log(struct super_block *sb) { … } static int open_dummy_log(struct super_block *sb) { … } /* * NAME: lmLogInit() * * FUNCTION: log initialization at first log open. * * logredo() (or logformat()) should have been run previously. * initialize the log from log superblock. * set the log state in the superblock to LOGMOUNT and * write SYNCPT log record. * * PARAMETER: log - log structure * * RETURN: 0 - if ok * -EINVAL - bad log magic number or superblock dirty * error returned from logwait() * * serialization: single first open thread */ int lmLogInit(struct jfs_log * log) { … } /* * NAME: lmLogClose() * * FUNCTION: remove file system <ipmnt> from active list of log <iplog> * and close it on last close. * * PARAMETER: sb - superblock * * RETURN: errors from subroutines * * serialization: */ int lmLogClose(struct super_block *sb) { … } /* * NAME: jfs_flush_journal() * * FUNCTION: initiate write of any outstanding transactions to the journal * and optionally wait until they are all written to disk * * wait == 0 flush until latest txn is committed, don't wait * wait == 1 flush until latest txn is committed, wait * wait > 1 flush until all txn's are complete, wait */ void jfs_flush_journal(struct jfs_log *log, int wait) { … } /* * NAME: lmLogShutdown() * * FUNCTION: log shutdown at last LogClose(). * * write log syncpt record. * update super block to set redone flag to 0. * * PARAMETER: log - log inode * * RETURN: 0 - success * * serialization: single last close thread */ int lmLogShutdown(struct jfs_log * log) { … } /* * NAME: lmLogFileSystem() * * FUNCTION: insert (<activate> = true)/remove (<activate> = false) * file system into/from log active file system list. * * PARAMETE: log - pointer to logs inode. * fsdev - kdev_t of filesystem. * serial - pointer to returned log serial number * activate - insert/remove device from active list. * * RETURN: 0 - success * errors returned by vms_iowait(). */ static int lmLogFileSystem(struct jfs_log * log, struct jfs_sb_info *sbi, int activate) { … } /* * log buffer manager (lbm) * ------------------------ * * special purpose buffer manager supporting log i/o requirements. * * per log write queue: * log pageout occurs in serial order by fifo write queue and * restricting to a single i/o in pregress at any one time. * a circular singly-linked list * (log->wrqueue points to the tail, and buffers are linked via * bp->wrqueue field), and * maintains log page in pageout ot waiting for pageout in serial pageout. */ /* * lbmLogInit() * * initialize per log I/O setup at lmLogInit() */ static int lbmLogInit(struct jfs_log * log) { … } /* * lbmLogShutdown() * * finalize per log I/O setup at lmLogShutdown() */ static void lbmLogShutdown(struct jfs_log * log) { … } /* * lbmAllocate() * * allocate an empty log buffer */ static struct lbuf *lbmAllocate(struct jfs_log * log, int pn) { … } /* * lbmFree() * * release a log buffer to freelist */ static void lbmFree(struct lbuf * bp) { … } static void lbmfree(struct lbuf * bp) { … } /* * NAME: lbmRedrive * * FUNCTION: add a log buffer to the log redrive list * * PARAMETER: * bp - log buffer * * NOTES: * Takes log_redrive_lock. */ static inline void lbmRedrive(struct lbuf *bp) { … } /* * lbmRead() */ static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp) { … } /* * lbmWrite() * * buffer at head of pageout queue stays after completion of * partial-page pageout and redriven by explicit initiation of * pageout by caller until full-page pageout is completed and * released. * * device driver i/o done redrives pageout of new buffer at * head of pageout queue when current buffer at head of pageout * queue is released at the completion of its full-page pageout. * * LOGGC_LOCK() serializes lbmWrite() by lmNextPage() and lmGroupCommit(). * LCACHE_LOCK() serializes xflag between lbmWrite() and lbmIODone() */ static void lbmWrite(struct jfs_log * log, struct lbuf * bp, int flag, int cant_block) { … } /* * lbmDirectWrite() * * initiate pageout bypassing write queue for sidestream * (e.g., log superblock) write; */ static void lbmDirectWrite(struct jfs_log * log, struct lbuf * bp, int flag) { … } /* * NAME: lbmStartIO() * * FUNCTION: Interface to DD strategy routine * * RETURN: none * * serialization: LCACHE_LOCK() is NOT held during log i/o; */ static void lbmStartIO(struct lbuf * bp) { … } /* * lbmIOWait() */ static int lbmIOWait(struct lbuf * bp, int flag) { … } /* * lbmIODone() * * executed at INTIODONE level */ static void lbmIODone(struct bio *bio) { … } int jfsIOWait(void *arg) { … } /* * NAME: lmLogFormat()/jfs_logform() * * FUNCTION: format file system log * * PARAMETERS: * log - volume log * logAddress - start address of log space in FS block * logSize - length of log space in FS block; * * RETURN: 0 - success * -EIO - i/o error * * XXX: We're synchronously writing one page at a time. This needs to * be improved by writing multiple pages at once. */ int lmLogFormat(struct jfs_log *log, s64 logAddress, int logSize) { … } #ifdef CONFIG_JFS_STATISTICS int jfs_lmstats_proc_show(struct seq_file *m, void *v) { … } #endif /* CONFIG_JFS_STATISTICS */
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