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Diffstat (limited to 'fs/xfs/xfs_log.c')
| -rw-r--r-- | fs/xfs/xfs_log.c | 3560 |
1 files changed, 3560 insertions, 0 deletions
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c new file mode 100644 index 000000000000..092d5fb096b1 --- /dev/null +++ b/fs/xfs/xfs_log.c @@ -0,0 +1,3560 @@ +/* + * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. + * + * Further, this software is distributed without any warranty that it is + * free of the rightful claim of any third person regarding infringement + * or the like. Any license provided herein, whether implied or + * otherwise, applies only to this software file. Patent licenses, if + * any, provided herein do not apply to combinations of this program with + * other software, or any other product whatsoever. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write the Free Software Foundation, Inc., 59 + * Temple Place - Suite 330, Boston MA 02111-1307, USA. + * + * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy, + * Mountain View, CA 94043, or: + * + * http://www.sgi.com + * + * For further information regarding this notice, see: + * + * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/ + */ + +/* + * High level interface routines for log manager + */ + +#include "xfs.h" +#include "xfs_macros.h" +#include "xfs_types.h" +#include "xfs_inum.h" +#include "xfs_ag.h" +#include "xfs_sb.h" +#include "xfs_log.h" +#include "xfs_trans.h" +#include "xfs_dir.h" +#include "xfs_dmapi.h" +#include "xfs_mount.h" +#include "xfs_error.h" +#include "xfs_log_priv.h" +#include "xfs_buf_item.h" +#include "xfs_alloc_btree.h" +#include "xfs_log_recover.h" +#include "xfs_bit.h" +#include "xfs_rw.h" +#include "xfs_trans_priv.h" + + +#define xlog_write_adv_cnt(ptr, len, off, bytes) \ + { (ptr) += (bytes); \ + (len) -= (bytes); \ + (off) += (bytes);} + +/* Local miscellaneous function prototypes */ +STATIC int xlog_bdstrat_cb(struct xfs_buf *); +STATIC int xlog_commit_record(xfs_mount_t *mp, xlog_ticket_t *ticket, + xlog_in_core_t **, xfs_lsn_t *); +STATIC xlog_t * xlog_alloc_log(xfs_mount_t *mp, + xfs_buftarg_t *log_target, + xfs_daddr_t blk_offset, + int num_bblks); +STATIC int xlog_space_left(xlog_t *log, int cycle, int bytes); +STATIC int xlog_sync(xlog_t *log, xlog_in_core_t *iclog); +STATIC void xlog_unalloc_log(xlog_t *log); +STATIC int xlog_write(xfs_mount_t *mp, xfs_log_iovec_t region[], + int nentries, xfs_log_ticket_t tic, + xfs_lsn_t *start_lsn, + xlog_in_core_t **commit_iclog, + uint flags); + +/* local state machine functions */ +STATIC void xlog_state_done_syncing(xlog_in_core_t *iclog, int); +STATIC void xlog_state_do_callback(xlog_t *log,int aborted, xlog_in_core_t *iclog); +STATIC int xlog_state_get_iclog_space(xlog_t *log, + int len, + xlog_in_core_t **iclog, + xlog_ticket_t *ticket, + int *continued_write, + int *logoffsetp); +STATIC void xlog_state_put_ticket(xlog_t *log, + xlog_ticket_t *tic); +STATIC int xlog_state_release_iclog(xlog_t *log, + xlog_in_core_t *iclog); +STATIC void xlog_state_switch_iclogs(xlog_t *log, + xlog_in_core_t *iclog, + int eventual_size); +STATIC int xlog_state_sync(xlog_t *log, xfs_lsn_t lsn, uint flags); +STATIC int xlog_state_sync_all(xlog_t *log, uint flags); +STATIC void xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog); + +/* local functions to manipulate grant head */ +STATIC int xlog_grant_log_space(xlog_t *log, + xlog_ticket_t *xtic); +STATIC void xlog_grant_push_ail(xfs_mount_t *mp, + int need_bytes); +STATIC void xlog_regrant_reserve_log_space(xlog_t *log, + xlog_ticket_t *ticket); +STATIC int xlog_regrant_write_log_space(xlog_t *log, + xlog_ticket_t *ticket); +STATIC void xlog_ungrant_log_space(xlog_t *log, + xlog_ticket_t *ticket); + + +/* local ticket functions */ +STATIC void xlog_state_ticket_alloc(xlog_t *log); +STATIC xlog_ticket_t *xlog_ticket_get(xlog_t *log, + int unit_bytes, + int count, + char clientid, + uint flags); +STATIC void xlog_ticket_put(xlog_t *log, xlog_ticket_t *ticket); + +/* local debug functions */ +#if defined(DEBUG) && !defined(XLOG_NOLOG) +STATIC void xlog_verify_dest_ptr(xlog_t *log, __psint_t ptr); +STATIC void xlog_verify_grant_head(xlog_t *log, int equals); +STATIC void xlog_verify_iclog(xlog_t *log, xlog_in_core_t *iclog, + int count, boolean_t syncing); +STATIC void xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog, + xfs_lsn_t tail_lsn); +#else +#define xlog_verify_dest_ptr(a,b) +#define xlog_verify_grant_head(a,b) +#define xlog_verify_iclog(a,b,c,d) +#define xlog_verify_tail_lsn(a,b,c) +#endif + +int xlog_iclogs_empty(xlog_t *log); + +#ifdef DEBUG +int xlog_do_error = 0; +int xlog_req_num = 0; +int xlog_error_mod = 33; +#endif + +#define XLOG_FORCED_SHUTDOWN(log) (log->l_flags & XLOG_IO_ERROR) + +/* + * 0 => disable log manager + * 1 => enable log manager + * 2 => enable log manager and log debugging + */ +#if defined(XLOG_NOLOG) || defined(DEBUG) +int xlog_debug = 1; +xfs_buftarg_t *xlog_target; +#endif + +#if defined(XFS_LOG_TRACE) + +void +xlog_trace_loggrant(xlog_t *log, xlog_ticket_t *tic, xfs_caddr_t string) +{ + if (! log->l_grant_trace) { + log->l_grant_trace = ktrace_alloc(1024, KM_NOSLEEP); + if (! log->l_grant_trace) + return; + } + + ktrace_enter(log->l_grant_trace, + (void *)tic, + (void *)log->l_reserve_headq, + (void *)log->l_write_headq, + (void *)((unsigned long)log->l_grant_reserve_cycle), + (void *)((unsigned long)log->l_grant_reserve_bytes), + (void *)((unsigned long)log->l_grant_write_cycle), + (void *)((unsigned long)log->l_grant_write_bytes), + (void *)((unsigned long)log->l_curr_cycle), + (void *)((unsigned long)log->l_curr_block), + (void *)((unsigned long)CYCLE_LSN(log->l_tail_lsn)), + (void *)((unsigned long)BLOCK_LSN(log->l_tail_lsn)), + (void *)string, + (void *)((unsigned long)13), + (void *)((unsigned long)14), + (void *)((unsigned long)15), + (void *)((unsigned long)16)); +} + +void +xlog_trace_iclog(xlog_in_core_t *iclog, uint state) +{ + pid_t pid; + + pid = current_pid(); + + if (!iclog->ic_trace) + iclog->ic_trace = ktrace_alloc(256, KM_SLEEP); + ktrace_enter(iclog->ic_trace, + (void *)((unsigned long)state), + (void *)((unsigned long)pid), + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0, + (void *)0); +} + +#else +#define xlog_trace_loggrant(log,tic,string) +#define xlog_trace_iclog(iclog,state) +#endif /* XFS_LOG_TRACE */ + +/* + * NOTES: + * + * 1. currblock field gets updated at startup and after in-core logs + * marked as with WANT_SYNC. + */ + +/* + * This routine is called when a user of a log manager ticket is done with + * the reservation. If the ticket was ever used, then a commit record for + * the associated transaction is written out as a log operation header with + * no data. The flag XLOG_TIC_INITED is set when the first write occurs with + * a given ticket. If the ticket was one with a permanent reservation, then + * a few operations are done differently. Permanent reservation tickets by + * default don't release the reservation. They just commit the current + * transaction with the belief that the reservation is still needed. A flag + * must be passed in before permanent reservations are actually released. + * When these type of tickets are not released, they need to be set into + * the inited state again. By doing this, a start record will be written + * out when the next write occurs. + */ +xfs_lsn_t +xfs_log_done(xfs_mount_t *mp, + xfs_log_ticket_t xtic, + void **iclog, + uint flags) +{ + xlog_t *log = mp->m_log; + xlog_ticket_t *ticket = (xfs_log_ticket_t) xtic; + xfs_lsn_t lsn = 0; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug && xlog_target == log->l_targ) + return 0; +#endif + + if (XLOG_FORCED_SHUTDOWN(log) || + /* + * If nothing was ever written, don't write out commit record. + * If we get an error, just continue and give back the log ticket. + */ + (((ticket->t_flags & XLOG_TIC_INITED) == 0) && + (xlog_commit_record(mp, ticket, + (xlog_in_core_t **)iclog, &lsn)))) { + lsn = (xfs_lsn_t) -1; + if (ticket->t_flags & XLOG_TIC_PERM_RESERV) { + flags |= XFS_LOG_REL_PERM_RESERV; + } + } + + + if ((ticket->t_flags & XLOG_TIC_PERM_RESERV) == 0 || + (flags & XFS_LOG_REL_PERM_RESERV)) { + /* + * Release ticket if not permanent reservation or a specifc + * request has been made to release a permanent reservation. + */ + xlog_ungrant_log_space(log, ticket); + xlog_state_put_ticket(log, ticket); + } else { + xlog_regrant_reserve_log_space(log, ticket); + } + + /* If this ticket was a permanent reservation and we aren't + * trying to release it, reset the inited flags; so next time + * we write, a start record will be written out. + */ + if ((ticket->t_flags & XLOG_TIC_PERM_RESERV) && + (flags & XFS_LOG_REL_PERM_RESERV) == 0) + ticket->t_flags |= XLOG_TIC_INITED; + + return lsn; +} /* xfs_log_done */ + + +/* + * Force the in-core log to disk. If flags == XFS_LOG_SYNC, + * the force is done synchronously. + * + * Asynchronous forces are implemented by setting the WANT_SYNC + * bit in the appropriate in-core log and then returning. + * + * Synchronous forces are implemented with a semaphore. All callers + * to force a given lsn to disk will wait on a semaphore attached to the + * specific in-core log. When given in-core log finally completes its + * write to disk, that thread will wake up all threads waiting on the + * semaphore. + */ +int +xfs_log_force(xfs_mount_t *mp, + xfs_lsn_t lsn, + uint flags) +{ + int rval; + xlog_t *log = mp->m_log; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug && xlog_target == log->l_targ) + return 0; +#endif + + ASSERT(flags & XFS_LOG_FORCE); + + XFS_STATS_INC(xs_log_force); + + if ((log->l_flags & XLOG_IO_ERROR) == 0) { + if (lsn == 0) + rval = xlog_state_sync_all(log, flags); + else + rval = xlog_state_sync(log, lsn, flags); + } else { + rval = XFS_ERROR(EIO); + } + + return rval; + +} /* xfs_log_force */ + +/* + * Attaches a new iclog I/O completion callback routine during + * transaction commit. If the log is in error state, a non-zero + * return code is handed back and the caller is responsible for + * executing the callback at an appropriate time. + */ +int +xfs_log_notify(xfs_mount_t *mp, /* mount of partition */ + void *iclog_hndl, /* iclog to hang callback off */ + xfs_log_callback_t *cb) +{ + xlog_t *log = mp->m_log; + xlog_in_core_t *iclog = (xlog_in_core_t *)iclog_hndl; + int abortflg, spl; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug && xlog_target == log->l_targ) + return 0; +#endif + cb->cb_next = NULL; + spl = LOG_LOCK(log); + abortflg = (iclog->ic_state & XLOG_STATE_IOERROR); + if (!abortflg) { + ASSERT_ALWAYS((iclog->ic_state == XLOG_STATE_ACTIVE) || + (iclog->ic_state == XLOG_STATE_WANT_SYNC)); + cb->cb_next = NULL; + *(iclog->ic_callback_tail) = cb; + iclog->ic_callback_tail = &(cb->cb_next); + } + LOG_UNLOCK(log, spl); + return abortflg; +} /* xfs_log_notify */ + +int +xfs_log_release_iclog(xfs_mount_t *mp, + void *iclog_hndl) +{ + xlog_t *log = mp->m_log; + xlog_in_core_t *iclog = (xlog_in_core_t *)iclog_hndl; + + if (xlog_state_release_iclog(log, iclog)) { + xfs_force_shutdown(mp, XFS_LOG_IO_ERROR); + return(EIO); + } + + return 0; +} + +/* + * 1. Reserve an amount of on-disk log space and return a ticket corresponding + * to the reservation. + * 2. Potentially, push buffers at tail of log to disk. + * + * Each reservation is going to reserve extra space for a log record header. + * When writes happen to the on-disk log, we don't subtract the length of the + * log record header from any reservation. By wasting space in each + * reservation, we prevent over allocation problems. + */ +int +xfs_log_reserve(xfs_mount_t *mp, + int unit_bytes, + int cnt, + xfs_log_ticket_t *ticket, + __uint8_t client, + uint flags) +{ + xlog_t *log = mp->m_log; + xlog_ticket_t *internal_ticket; + int retval; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug && xlog_target == log->l_targ) + return 0; +#endif + retval = 0; + ASSERT(client == XFS_TRANSACTION || client == XFS_LOG); + ASSERT((flags & XFS_LOG_NOSLEEP) == 0); + + if (XLOG_FORCED_SHUTDOWN(log)) + return XFS_ERROR(EIO); + + XFS_STATS_INC(xs_try_logspace); + + if (*ticket != NULL) { + ASSERT(flags & XFS_LOG_PERM_RESERV); + internal_ticket = (xlog_ticket_t *)*ticket; + xlog_grant_push_ail(mp, internal_ticket->t_unit_res); + retval = xlog_regrant_write_log_space(log, internal_ticket); + } else { + /* may sleep if need to allocate more tickets */ + internal_ticket = xlog_ticket_get(log, unit_bytes, cnt, + client, flags); + *ticket = internal_ticket; + xlog_grant_push_ail(mp, + (internal_ticket->t_unit_res * + internal_ticket->t_cnt)); + retval = xlog_grant_log_space(log, internal_ticket); + } + + return retval; +} /* xfs_log_reserve */ + + +/* + * Mount a log filesystem + * + * mp - ubiquitous xfs mount point structure + * log_target - buftarg of on-disk log device + * blk_offset - Start block # where block size is 512 bytes (BBSIZE) + * num_bblocks - Number of BBSIZE blocks in on-disk log + * + * Return error or zero. + */ +int +xfs_log_mount(xfs_mount_t *mp, + xfs_buftarg_t *log_target, + xfs_daddr_t blk_offset, + int num_bblks) +{ + if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) + cmn_err(CE_NOTE, "XFS mounting filesystem %s", mp->m_fsname); + else { + cmn_err(CE_NOTE, + "!Mounting filesystem \"%s\" in no-recovery mode. Filesystem will be inconsistent.", + mp->m_fsname); + ASSERT(XFS_MTOVFS(mp)->vfs_flag & VFS_RDONLY); + } + + mp->m_log = xlog_alloc_log(mp, log_target, blk_offset, num_bblks); + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug) { + cmn_err(CE_NOTE, "log dev: %s", XFS_BUFTARG_NAME(log_target)); + return 0; + } +#endif + /* + * skip log recovery on a norecovery mount. pretend it all + * just worked. + */ + if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) { + int error; + vfs_t *vfsp = XFS_MTOVFS(mp); + int readonly = (vfsp->vfs_flag & VFS_RDONLY); + + if (readonly) + vfsp->vfs_flag &= ~VFS_RDONLY; + + error = xlog_recover(mp->m_log, readonly); + + if (readonly) + vfsp->vfs_flag |= VFS_RDONLY; + if (error) { + cmn_err(CE_WARN, "XFS: log mount/recovery failed: error %d", error); + xlog_unalloc_log(mp->m_log); + return error; + } + } + + /* Normal transactions can now occur */ + mp->m_log->l_flags &= ~XLOG_ACTIVE_RECOVERY; + + /* End mounting message in xfs_log_mount_finish */ + return 0; +} /* xfs_log_mount */ + +/* + * Finish the recovery of the file system. This is separate from + * the xfs_log_mount() call, because it depends on the code in + * xfs_mountfs() to read in the root and real-time bitmap inodes + * between calling xfs_log_mount() and here. + * + * mp - ubiquitous xfs mount point structure + */ +int +xfs_log_mount_finish(xfs_mount_t *mp, int mfsi_flags) +{ + int error; + + if (!(mp->m_flags & XFS_MOUNT_NORECOVERY)) + error = xlog_recover_finish(mp->m_log, mfsi_flags); + else { + error = 0; + ASSERT(XFS_MTOVFS(mp)->vfs_flag & VFS_RDONLY); + } + + return error; +} + +/* + * Unmount processing for the log. + */ +int +xfs_log_unmount(xfs_mount_t *mp) +{ + int error; + + error = xfs_log_unmount_write(mp); + xfs_log_unmount_dealloc(mp); + return (error); +} + +/* + * Final log writes as part of unmount. + * + * Mark the filesystem clean as unmount happens. Note that during relocation + * this routine needs to be executed as part of source-bag while the + * deallocation must not be done until source-end. + */ + +/* + * Unmount record used to have a string "Unmount filesystem--" in the + * data section where the "Un" was really a magic number (XLOG_UNMOUNT_TYPE). + * We just write the magic number now since that particular field isn't + * currently architecture converted and "nUmount" is a bit foo. + * As far as I know, there weren't any dependencies on the old behaviour. + */ + +int +xfs_log_unmount_write(xfs_mount_t *mp) +{ + xlog_t *log = mp->m_log; + xlog_in_core_t *iclog; +#ifdef DEBUG + xlog_in_core_t *first_iclog; +#endif + xfs_log_iovec_t reg[1]; + xfs_log_ticket_t tic = NULL; + xfs_lsn_t lsn; + int error; + SPLDECL(s); + + /* the data section must be 32 bit size aligned */ + struct { + __uint16_t magic; + __uint16_t pad1; + __uint32_t pad2; /* may as well make it 64 bits */ + } magic = { XLOG_UNMOUNT_TYPE, 0, 0 }; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug && xlog_target == log->l_targ) + return 0; +#endif + + /* + * Don't write out unmount record on read-only mounts. + * Or, if we are doing a forced umount (typically because of IO errors). + */ + if (XFS_MTOVFS(mp)->vfs_flag & VFS_RDONLY) + return 0; + + xfs_log_force(mp, 0, XFS_LOG_FORCE|XFS_LOG_SYNC); + +#ifdef DEBUG + first_iclog = iclog = log->l_iclog; + do { + if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { + ASSERT(iclog->ic_state & XLOG_STATE_ACTIVE); + ASSERT(iclog->ic_offset == 0); + } + iclog = iclog->ic_next; + } while (iclog != first_iclog); +#endif + if (! (XLOG_FORCED_SHUTDOWN(log))) { + reg[0].i_addr = (void*)&magic; + reg[0].i_len = sizeof(magic); + + error = xfs_log_reserve(mp, 600, 1, &tic, XFS_LOG, 0); + if (!error) { + /* remove inited flag */ + ((xlog_ticket_t *)tic)->t_flags = 0; + error = xlog_write(mp, reg, 1, tic, &lsn, + NULL, XLOG_UNMOUNT_TRANS); + /* + * At this point, we're umounting anyway, + * so there's no point in transitioning log state + * to IOERROR. Just continue... + */ + } + + if (error) { + xfs_fs_cmn_err(CE_ALERT, mp, + "xfs_log_unmount: unmount record failed"); + } + + + s = LOG_LOCK(log); + iclog = log->l_iclog; + iclog->ic_refcnt++; + LOG_UNLOCK(log, s); + xlog_state_want_sync(log, iclog); + (void) xlog_state_release_iclog(log, iclog); + + s = LOG_LOCK(log); + if (!(iclog->ic_state == XLOG_STATE_ACTIVE || + iclog->ic_state == XLOG_STATE_DIRTY)) { + if (!XLOG_FORCED_SHUTDOWN(log)) { + sv_wait(&iclog->ic_forcesema, PMEM, + &log->l_icloglock, s); + } else { + LOG_UNLOCK(log, s); + } + } else { + LOG_UNLOCK(log, s); + } + if (tic) + xlog_state_put_ticket(log, tic); + } else { + /* + * We're already in forced_shutdown mode, couldn't + * even attempt to write out the unmount transaction. + * + * Go through the motions of sync'ing and releasing + * the iclog, even though no I/O will actually happen, + * we need to wait for other log I/O's that may already + * be in progress. Do this as a separate section of + * code so we'll know if we ever get stuck here that + * we're in this odd situation of trying to unmount + * a file system that went into forced_shutdown as + * the result of an unmount.. + */ + s = LOG_LOCK(log); + iclog = log->l_iclog; + iclog->ic_refcnt++; + LOG_UNLOCK(log, s); + + xlog_state_want_sync(log, iclog); + (void) xlog_state_release_iclog(log, iclog); + + s = LOG_LOCK(log); + + if ( ! ( iclog->ic_state == XLOG_STATE_ACTIVE + || iclog->ic_state == XLOG_STATE_DIRTY + || iclog->ic_state == XLOG_STATE_IOERROR) ) { + + sv_wait(&iclog->ic_forcesema, PMEM, + &log->l_icloglock, s); + } else { + LOG_UNLOCK(log, s); + } + } + + return 0; +} /* xfs_log_unmount_write */ + +/* + * Deallocate log structures for unmount/relocation. + */ +void +xfs_log_unmount_dealloc(xfs_mount_t *mp) +{ + xlog_unalloc_log(mp->m_log); +} + +/* + * Write region vectors to log. The write happens using the space reservation + * of the ticket (tic). It is not a requirement that all writes for a given + * transaction occur with one call to xfs_log_write(). + */ +int +xfs_log_write(xfs_mount_t * mp, + xfs_log_iovec_t reg[], + int nentries, + xfs_log_ticket_t tic, + xfs_lsn_t *start_lsn) +{ + int error; + xlog_t *log = mp->m_log; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug && xlog_target == log->l_targ) { + *start_lsn = 0; + return 0; + } +#endif + if (XLOG_FORCED_SHUTDOWN(log)) + return XFS_ERROR(EIO); + + if ((error = xlog_write(mp, reg, nentries, tic, start_lsn, NULL, 0))) { + xfs_force_shutdown(mp, XFS_LOG_IO_ERROR); + } + return (error); +} /* xfs_log_write */ + + +void +xfs_log_move_tail(xfs_mount_t *mp, + xfs_lsn_t tail_lsn) +{ + xlog_ticket_t *tic; + xlog_t *log = mp->m_log; + int need_bytes, free_bytes, cycle, bytes; + SPLDECL(s); + +#if defined(DEBUG) || defined(XLOG_NOLOG) + if (!xlog_debug && xlog_target == log->l_targ) + return; +#endif + /* XXXsup tmp */ + if (XLOG_FORCED_SHUTDOWN(log)) + return; + ASSERT(!XFS_FORCED_SHUTDOWN(mp)); + + if (tail_lsn == 0) { + /* needed since sync_lsn is 64 bits */ + s = LOG_LOCK(log); + tail_lsn = log->l_last_sync_lsn; + LOG_UNLOCK(log, s); + } + + s = GRANT_LOCK(log); + + /* Also an invalid lsn. 1 implies that we aren't passing in a valid + * tail_lsn. + */ + if (tail_lsn != 1) { + log->l_tail_lsn = tail_lsn; + } + + if ((tic = log->l_write_headq)) { +#ifdef DEBUG + if (log->l_flags & XLOG_ACTIVE_RECOVERY) + panic("Recovery problem"); +#endif + cycle = log->l_grant_write_cycle; + bytes = log->l_grant_write_bytes; + free_bytes = xlog_space_left(log, cycle, bytes); + do { + ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV); + + if (free_bytes < tic->t_unit_res && tail_lsn != 1) + break; + tail_lsn = 0; + free_bytes -= tic->t_unit_res; + sv_signal(&tic->t_sema); + tic = tic->t_next; + } while (tic != log->l_write_headq); + } + if ((tic = log->l_reserve_headq)) { +#ifdef DEBUG + if (log->l_flags & XLOG_ACTIVE_RECOVERY) + panic("Recovery problem"); +#endif + cycle = log->l_grant_reserve_cycle; + bytes = log->l_grant_reserve_bytes; + free_bytes = xlog_space_left(log, cycle, bytes); + do { + if (tic->t_flags & XLOG_TIC_PERM_RESERV) + need_bytes = tic->t_unit_res*tic->t_cnt; + else + need_bytes = tic->t_unit_res; + if (free_bytes < need_bytes && tail_lsn != 1) + break; + tail_lsn = 0; + free_bytes -= need_bytes; + sv_signal(&tic->t_sema); + tic = tic->t_next; + } while (tic != log->l_reserve_headq); + } + GRANT_UNLOCK(log, s); +} /* xfs_log_move_tail */ + +/* + * Determine if we have a transaction that has gone to disk + * that needs to be covered. Log activity needs to be idle (no AIL and + * nothing in the iclogs). And, we need to be in the right state indicating + * something has gone out. + */ +int +xfs_log_need_covered(xfs_mount_t *mp) +{ + SPLDECL(s); + int needed = 0, gen; + xlog_t *log = mp->m_log; + vfs_t *vfsp = XFS_MTOVFS(mp); + + if (fs_frozen(vfsp) || XFS_FORCED_SHUTDOWN(mp) || + (vfsp->vfs_flag & VFS_RDONLY)) + return 0; + + s = LOG_LOCK(log); + if (((log->l_covered_state == XLOG_STATE_COVER_NEED) || + (log->l_covered_state == XLOG_STATE_COVER_NEED2)) + && !xfs_trans_first_ail(mp, &gen) + && xlog_iclogs_empty(log)) { + if (log->l_covered_state == XLOG_STATE_COVER_NEED) + log->l_covered_state = XLOG_STATE_COVER_DONE; + else { + ASSERT(log->l_covered_state == XLOG_STATE_COVER_NEED2); + log->l_covered_state = XLOG_STATE_COVER_DONE2; + } + needed = 1; + } + LOG_UNLOCK(log, s); + return(needed); +} + +/****************************************************************************** + * + * local routines + * + ****************************************************************************** + */ + +/* xfs_trans_tail_ail returns 0 when there is nothing in the list. + * The log manager must keep track of the last LR which was committed + * to disk. The lsn of this LR will become the new tail_lsn whenever + * xfs_trans_tail_ail returns 0. If we don't do this, we run into + * the situation where stuff could be written into the log but nothing + * was ever in the AIL when asked. Eventually, we panic since the + * tail hits the head. + * + * We may be holding the log iclog lock upon entering this routine. + */ +xfs_lsn_t +xlog_assign_tail_lsn(xfs_mount_t *mp) +{ + xfs_lsn_t tail_lsn; + SPLDECL(s); + xlog_t *log = mp->m_log; + + tail_lsn = xfs_trans_tail_ail(mp); + s = GRANT_LOCK(log); + if (tail_lsn != 0) { + log->l_tail_lsn = tail_lsn; + } else { + tail_lsn = log->l_tail_lsn = log->l_last_sync_lsn; + } + GRANT_UNLOCK(log, s); + + return tail_lsn; +} /* xlog_assign_tail_lsn */ + + +/* + * Return the space in the log between the tail and the head. The head + * is passed in the cycle/bytes formal parms. In the special case where + * the reserve head has wrapped passed the tail, this calculation is no + * longer valid. In this case, just return 0 which means there is no space + * in the log. This works for all places where this function is called + * with the reserve head. Of course, if the write head were to ever + * wrap the tail, we should blow up. Rather than catch this case here, + * we depend on other ASSERTions in other parts of the code. XXXmiken + * + * This code also handles the case where the reservation head is behind + * the tail. The details of this case are described below, but the end + * result is that we return the size of the log as the amount of space left. + */ +int +xlog_space_left(xlog_t *log, int cycle, int bytes) +{ + int free_bytes; + int tail_bytes; + int tail_cycle; + + tail_bytes = BBTOB(BLOCK_LSN(log->l_tail_lsn)); + tail_cycle = CYCLE_LSN(log->l_tail_lsn); + if ((tail_cycle == cycle) && (bytes >= tail_bytes)) { + free_bytes = log->l_logsize - (bytes - tail_bytes); + } else if ((tail_cycle + 1) < cycle) { + return 0; + } else if (tail_cycle < cycle) { + ASSERT(tail_cycle == (cycle - 1)); + free_bytes = tail_bytes - bytes; + } else { + /* + * The reservation head is behind the tail. + * In this case we just want to return the size of the + * log as the amount of space left. + */ + xfs_fs_cmn_err(CE_ALERT, log->l_mp, + "xlog_space_left: head behind tail\n" + " tail_cycle = %d, tail_bytes = %d\n" + " GH cycle = %d, GH bytes = %d", + tail_cycle, tail_bytes, cycle, bytes); + ASSERT(0); + free_bytes = log->l_logsize; + } + return free_bytes; +} /* xlog_space_left */ + + +/* + * Log function which is called when an io completes. + * + * The log manager needs its own routine, in order to control what + * happens with the buffer after the write completes. + */ +void +xlog_iodone(xfs_buf_t *bp) +{ + xlog_in_core_t *iclog; + xlog_t *l; + int aborted; + + iclog = XFS_BUF_FSPRIVATE(bp, xlog_in_core_t *); + ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == (unsigned long) 2); + XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1); + aborted = 0; + + /* + * Some versions of cpp barf on the recursive definition of + * ic_log -> hic_fields.ic_log and expand ic_log twice when + * it is passed through two macros. Workaround broken cpp. + */ + l = iclog->ic_log; + + /* + * Race to shutdown the filesystem if we see an error. + */ + if (XFS_TEST_ERROR((XFS_BUF_GETERROR(bp)), l->l_mp, + XFS_ERRTAG_IODONE_IOERR, XFS_RANDOM_IODONE_IOERR)) { + xfs_ioerror_alert("xlog_iodone", l->l_mp, bp, XFS_BUF_ADDR(bp)); + XFS_BUF_STALE(bp); + xfs_force_shutdown(l->l_mp, XFS_LOG_IO_ERROR); + /* + * This flag will be propagated to the trans-committed + * callback routines to let them know that the log-commit + * didn't succeed. + */ + aborted = XFS_LI_ABORTED; + } else if (iclog->ic_state & XLOG_STATE_IOERROR) { + aborted = XFS_LI_ABORTED; + } + xlog_state_done_syncing(iclog, aborted); + if (!(XFS_BUF_ISASYNC(bp))) { + /* + * Corresponding psema() will be done in bwrite(). If we don't + * vsema() here, panic. + */ + XFS_BUF_V_IODONESEMA(bp); + } +} /* xlog_iodone */ + +/* + * The bdstrat callback function for log bufs. This gives us a central + * place to trap bufs in case we get hit by a log I/O error and need to + * shutdown. Actually, in practice, even when we didn't get a log error, + * we transition the iclogs to IOERROR state *after* flushing all existing + * iclogs to disk. This is because we don't want anymore new transactions to be + * started or completed afterwards. + */ +STATIC int +xlog_bdstrat_cb(struct xfs_buf *bp) +{ + xlog_in_core_t *iclog; + + iclog = XFS_BUF_FSPRIVATE(bp, xlog_in_core_t *); + + if ((iclog->ic_state & XLOG_STATE_IOERROR) == 0) { + /* note for irix bstrat will need struct bdevsw passed + * Fix the following macro if the code ever is merged + */ + XFS_bdstrat(bp); + return 0; + } + + xfs_buftrace("XLOG__BDSTRAT IOERROR", bp); + XFS_BUF_ERROR(bp, EIO); + XFS_BUF_STALE(bp); + xfs_biodone(bp); + return (XFS_ERROR(EIO)); + + +} + +/* + * Return size of each in-core log record buffer. + * + * Low memory machines only get 2 16KB buffers. We don't want to waste + * memory here. However, all other machines get at least 2 32KB buffers. + * The number is hard coded because we don't care about the minimum + * memory size, just 32MB systems. + * + * If the filesystem blocksize is too large, we may need to choose a + * larger size since the directory code currently logs entire blocks. + */ + +STATIC void +xlog_get_iclog_buffer_size(xfs_mount_t *mp, + xlog_t *log) +{ + int size; + int xhdrs; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + /* + * When logbufs == 0, someone has disabled the log from the FSTAB + * file. This is not a documented feature. We need to set xlog_debug + * to zero (this deactivates the log) and set xlog_target to the + * appropriate device. Only one filesystem may be affected as such + * since this is just a performance hack to test what we might be able + * to get if the log were not present. + */ + if (mp->m_logbufs == 0) { + xlog_debug = 0; + xlog_target = log->l_targ; + log->l_iclog_bufs = XLOG_MIN_ICLOGS; + } else +#endif + { + /* + * This is the normal path. If m_logbufs == -1, then the + * admin has chosen to use the system defaults for logbuffers. + */ + if (mp->m_logbufs == -1) { + if (xfs_physmem <= btoc(128*1024*1024)) { + log->l_iclog_bufs = XLOG_MIN_ICLOGS; + } else if (xfs_physmem <= btoc(400*1024*1024)) { + log->l_iclog_bufs = XLOG_MED_ICLOGS; + } else { + /* 256K with 32K bufs */ + log->l_iclog_bufs = XLOG_MAX_ICLOGS; + } + } else + log->l_iclog_bufs = mp->m_logbufs; + +#if defined(DEBUG) || defined(XLOG_NOLOG) + /* We are reactivating a filesystem after it was inactive */ + if (log->l_targ == xlog_target) { + xlog_target = NULL; + xlog_debug = 1; + } +#endif + } + + /* + * Buffer size passed in from mount system call. + */ + if (mp->m_logbsize != -1) { + size = log->l_iclog_size = mp->m_logbsize; + log->l_iclog_size_log = 0; + while (size != 1) { + log->l_iclog_size_log++; + size >>= 1; + } + + if (XFS_SB_VERSION_HASLOGV2(&mp->m_sb)) { + /* # headers = size / 32K + * one header holds cycles from 32K of data + */ + + xhdrs = mp->m_logbsize / XLOG_HEADER_CYCLE_SIZE; + if (mp->m_logbsize % XLOG_HEADER_CYCLE_SIZE) + xhdrs++; + log->l_iclog_hsize = xhdrs << BBSHIFT; + log->l_iclog_heads = xhdrs; + } else { + ASSERT(mp->m_logbsize <= XLOG_BIG_RECORD_BSIZE); + log->l_iclog_hsize = BBSIZE; + log->l_iclog_heads = 1; + } + return; + } + + /* + * Special case machines that have less than 32MB of memory. + * All machines with more memory use 32KB buffers. + */ + if (xfs_physmem <= btoc(32*1024*1024)) { + /* Don't change; min configuration */ + log->l_iclog_size = XLOG_RECORD_BSIZE; /* 16k */ + log->l_iclog_size_log = XLOG_RECORD_BSHIFT; + } else { + log->l_iclog_size = XLOG_BIG_RECORD_BSIZE; /* 32k */ + log->l_iclog_size_log = XLOG_BIG_RECORD_BSHIFT; + } + + /* the default log size is 16k or 32k which is one header sector */ + log->l_iclog_hsize = BBSIZE; + log->l_iclog_heads = 1; + + /* + * For 16KB, we use 3 32KB buffers. For 32KB block sizes, we use + * 4 32KB buffers. For 64KB block sizes, we use 8 32KB buffers. + */ + if (mp->m_sb.sb_blocksize >= 16*1024) { + log->l_iclog_size = XLOG_BIG_RECORD_BSIZE; + log->l_iclog_size_log = XLOG_BIG_RECORD_BSHIFT; + if (mp->m_logbufs == -1) { + switch (mp->m_sb.sb_blocksize) { + case 16*1024: /* 16 KB */ + log->l_iclog_bufs = 3; + break; + case 32*1024: /* 32 KB */ + log->l_iclog_bufs = 4; + break; + case 64*1024: /* 64 KB */ + log->l_iclog_bufs = 8; + break; + default: + xlog_panic("XFS: Invalid blocksize"); + break; + } + } + } +} /* xlog_get_iclog_buffer_size */ + + +/* + * This routine initializes some of the log structure for a given mount point. + * Its primary purpose is to fill in enough, so recovery can occur. However, + * some other stuff may be filled in too. + */ +STATIC xlog_t * +xlog_alloc_log(xfs_mount_t *mp, + xfs_buftarg_t *log_target, + xfs_daddr_t blk_offset, + int num_bblks) +{ + xlog_t *log; + xlog_rec_header_t *head; + xlog_in_core_t **iclogp; + xlog_in_core_t *iclog, *prev_iclog=NULL; + xfs_buf_t *bp; + int i; + int iclogsize; + + log = (xlog_t *)kmem_zalloc(sizeof(xlog_t), KM_SLEEP); + + log->l_mp = mp; + log->l_targ = log_target; + log->l_logsize = BBTOB(num_bblks); + log->l_logBBstart = blk_offset; + log->l_logBBsize = num_bblks; + log->l_covered_state = XLOG_STATE_COVER_IDLE; + log->l_flags |= XLOG_ACTIVE_RECOVERY; + + log->l_prev_block = -1; + ASSIGN_ANY_LSN_HOST(log->l_tail_lsn, 1, 0); + /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */ + log->l_last_sync_lsn = log->l_tail_lsn; + log->l_curr_cycle = 1; /* 0 is bad since this is initial value */ + log->l_grant_reserve_cycle = 1; + log->l_grant_write_cycle = 1; + + if (XFS_SB_VERSION_HASSECTOR(&mp->m_sb)) { + log->l_sectbb_log = mp->m_sb.sb_logsectlog - BBSHIFT; + ASSERT(log->l_sectbb_log <= mp->m_sectbb_log); + /* for larger sector sizes, must have v2 or external log */ + ASSERT(log->l_sectbb_log == 0 || + log->l_logBBstart == 0 || + XFS_SB_VERSION_HASLOGV2(&mp->m_sb)); + ASSERT(mp->m_sb.sb_logsectlog >= BBSHIFT); + } + log->l_sectbb_mask = (1 << log->l_sectbb_log) - 1; + + xlog_get_iclog_buffer_size(mp, log); + + bp = xfs_buf_get_empty(log->l_iclog_size, mp->m_logdev_targp); + XFS_BUF_SET_IODONE_FUNC(bp, xlog_iodone); + XFS_BUF_SET_BDSTRAT_FUNC(bp, xlog_bdstrat_cb); + XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1); + ASSERT(XFS_BUF_ISBUSY(bp)); + ASSERT(XFS_BUF_VALUSEMA(bp) <= 0); + log->l_xbuf = bp; + + spinlock_init(&log->l_icloglock, "iclog"); + spinlock_init(&log->l_grant_lock, "grhead_iclog"); + initnsema(&log->l_flushsema, 0, "ic-flush"); + xlog_state_ticket_alloc(log); /* wait until after icloglock inited */ + + /* log record size must be multiple of BBSIZE; see xlog_rec_header_t */ + ASSERT((XFS_BUF_SIZE(bp) & BBMASK) == 0); + + iclogp = &log->l_iclog; + /* + * The amount of memory to allocate for the iclog structure is + * rather funky due to the way the structure is defined. It is + * done this way so that we can use different sizes for machines + * with different amounts of memory. See the definition of + * xlog_in_core_t in xfs_log_priv.h for details. + */ + iclogsize = log->l_iclog_size; + ASSERT(log->l_iclog_size >= 4096); + for (i=0; i < log->l_iclog_bufs; i++) { + *iclogp = (xlog_in_core_t *) + kmem_zalloc(sizeof(xlog_in_core_t), KM_SLEEP); + iclog = *iclogp; + iclog->hic_data = (xlog_in_core_2_t *) + kmem_zalloc(iclogsize, KM_SLEEP); + + iclog->ic_prev = prev_iclog; + prev_iclog = iclog; + log->l_iclog_bak[i] = (xfs_caddr_t)&(iclog->ic_header); + + head = &iclog->ic_header; + memset(head, 0, sizeof(xlog_rec_header_t)); + INT_SET(head->h_magicno, ARCH_CONVERT, XLOG_HEADER_MAGIC_NUM); + INT_SET(head->h_version, ARCH_CONVERT, + XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) ? 2 : 1); + INT_SET(head->h_size, ARCH_CONVERT, log->l_iclog_size); + /* new fields */ + INT_SET(head->h_fmt, ARCH_CONVERT, XLOG_FMT); + memcpy(&head->h_fs_uuid, &mp->m_sb.sb_uuid, sizeof(uuid_t)); + + bp = xfs_buf_get_empty(log->l_iclog_size, mp->m_logdev_targp); + XFS_BUF_SET_IODONE_FUNC(bp, xlog_iodone); + XFS_BUF_SET_BDSTRAT_FUNC(bp, xlog_bdstrat_cb); + XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)1); + iclog->ic_bp = bp; + + iclog->ic_size = XFS_BUF_SIZE(bp) - log->l_iclog_hsize; + iclog->ic_state = XLOG_STATE_ACTIVE; + iclog->ic_log = log; + iclog->ic_callback_tail = &(iclog->ic_callback); + iclog->ic_datap = (char *)iclog->hic_data + log->l_iclog_hsize; + + ASSERT(XFS_BUF_ISBUSY(iclog->ic_bp)); + ASSERT(XFS_BUF_VALUSEMA(iclog->ic_bp) <= 0); + sv_init(&iclog->ic_forcesema, SV_DEFAULT, "iclog-force"); + sv_init(&iclog->ic_writesema, SV_DEFAULT, "iclog-write"); + + iclogp = &iclog->ic_next; + } + *iclogp = log->l_iclog; /* complete ring */ + log->l_iclog->ic_prev = prev_iclog; /* re-write 1st prev ptr */ + + return log; +} /* xlog_alloc_log */ + + +/* + * Write out the commit record of a transaction associated with the given + * ticket. Return the lsn of the commit record. + */ +STATIC int +xlog_commit_record(xfs_mount_t *mp, + xlog_ticket_t *ticket, + xlog_in_core_t **iclog, + xfs_lsn_t *commitlsnp) +{ + int error; + xfs_log_iovec_t reg[1]; + + reg[0].i_addr = NULL; + reg[0].i_len = 0; + + ASSERT_ALWAYS(iclog); + if ((error = xlog_write(mp, reg, 1, ticket, commitlsnp, + iclog, XLOG_COMMIT_TRANS))) { + xfs_force_shutdown(mp, XFS_LOG_IO_ERROR); + } + return (error); +} /* xlog_commit_record */ + + +/* + * Push on the buffer cache code if we ever use more than 75% of the on-disk + * log space. This code pushes on the lsn which would supposedly free up + * the 25% which we want to leave free. We may need to adopt a policy which + * pushes on an lsn which is further along in the log once we reach the high + * water mark. In this manner, we would be creating a low water mark. + */ +void +xlog_grant_push_ail(xfs_mount_t *mp, + int need_bytes) +{ + xlog_t *log = mp->m_log; /* pointer to the log */ + xfs_lsn_t tail_lsn; /* lsn of the log tail */ + xfs_lsn_t threshold_lsn = 0; /* lsn we'd like to be at */ + int free_blocks; /* free blocks left to write to */ + int free_bytes; /* free bytes left to write to */ + int threshold_block; /* block in lsn we'd like to be at */ + int threshold_cycle; /* lsn cycle we'd like to be at */ + int free_threshold; + SPLDECL(s); + + ASSERT(BTOBB(need_bytes) < log->l_logBBsize); + + s = GRANT_LOCK(log); + free_bytes = xlog_space_left(log, + log->l_grant_reserve_cycle, + log->l_grant_reserve_bytes); + tail_lsn = log->l_tail_lsn; + free_blocks = BTOBBT(free_bytes); + + /* + * Set the threshold for the minimum number of free blocks in the + * log to the maximum of what the caller needs, one quarter of the + * log, and 256 blocks. + */ + free_threshold = BTOBB(need_bytes); + free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2)); + free_threshold = MAX(free_threshold, 256); + if (free_blocks < free_threshold) { + threshold_block = BLOCK_LSN(tail_lsn) + free_threshold; + threshold_cycle = CYCLE_LSN(tail_lsn); + if (threshold_block >= log->l_logBBsize) { + threshold_block -= log->l_logBBsize; + threshold_cycle += 1; + } + ASSIGN_ANY_LSN_HOST(threshold_lsn, threshold_cycle, + threshold_block); + + /* Don't pass in an lsn greater than the lsn of the last + * log record known to be on disk. + */ + if (XFS_LSN_CMP(threshold_lsn, log->l_last_sync_lsn) > 0) + threshold_lsn = log->l_last_sync_lsn; + } + GRANT_UNLOCK(log, s); + + /* + * Get the transaction layer to kick the dirty buffers out to + * disk asynchronously. No point in trying to do this if + * the filesystem is shutting down. + */ + if (threshold_lsn && + !XLOG_FORCED_SHUTDOWN(log)) + xfs_trans_push_ail(mp, threshold_lsn); +} /* xlog_grant_push_ail */ + + +/* + * Flush out the in-core log (iclog) to the on-disk log in an asynchronous + * fashion. Previously, we should have moved the current iclog + * ptr in the log to point to the next available iclog. This allows further + * write to continue while this code syncs out an iclog ready to go. + * Before an in-core log can be written out, the data section must be scanned + * to save away the 1st word of each BBSIZE block into the header. We replace + * it with the current cycle count. Each BBSIZE block is tagged with the + * cycle count because there in an implicit assumption that drives will + * guarantee that entire 512 byte blocks get written at once. In other words, + * we can't have part of a 512 byte block written and part not written. By + * tagging each block, we will know which blocks are valid when recovering + * after an unclean shutdown. + * + * This routine is single threaded on the iclog. No other thread can be in + * this routine with the same iclog. Changing contents of iclog can there- + * fore be done without grabbing the state machine lock. Updating the global + * log will require grabbing the lock though. + * + * The entire log manager uses a logical block numbering scheme. Only + * log_sync (and then only bwrite()) know about the fact that the log may + * not start with block zero on a given device. The log block start offset + * is added immediately before calling bwrite(). + */ + +int +xlog_sync(xlog_t *log, + xlog_in_core_t *iclog) +{ + xfs_caddr_t dptr; /* pointer to byte sized element */ + xfs_buf_t *bp; + int i, ops; + uint count; /* byte count of bwrite */ + uint count_init; /* initial count before roundup */ + int roundoff; /* roundoff to BB or stripe */ + int split = 0; /* split write into two regions */ + int error; + SPLDECL(s); + int v2 = XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb); + + XFS_STATS_INC(xs_log_writes); + ASSERT(iclog->ic_refcnt == 0); + + /* Add for LR header */ + count_init = log->l_iclog_hsize + iclog->ic_offset; + + /* Round out the log write size */ + if (v2 && log->l_mp->m_sb.sb_logsunit > 1) { + /* we have a v2 stripe unit to use */ + count = XLOG_LSUNITTOB(log, XLOG_BTOLSUNIT(log, count_init)); + } else { + count = BBTOB(BTOBB(count_init)); + } + roundoff = count - count_init; + ASSERT(roundoff >= 0); + ASSERT((v2 && log->l_mp->m_sb.sb_logsunit > 1 && + roundoff < log->l_mp->m_sb.sb_logsunit) + || + (log->l_mp->m_sb.sb_logsunit <= 1 && + roundoff < BBTOB(1))); + + /* move grant heads by roundoff in sync */ + s = GRANT_LOCK(log); + XLOG_GRANT_ADD_SPACE(log, roundoff, 'w'); + XLOG_GRANT_ADD_SPACE(log, roundoff, 'r'); + GRANT_UNLOCK(log, s); + + /* put cycle number in every block */ + xlog_pack_data(log, iclog, roundoff); + + /* real byte length */ + if (v2) { + INT_SET(iclog->ic_header.h_len, + ARCH_CONVERT, + iclog->ic_offset + roundoff); + } else { + INT_SET(iclog->ic_header.h_len, ARCH_CONVERT, iclog->ic_offset); + } + + /* put ops count in correct order */ + ops = iclog->ic_header.h_num_logops; + INT_SET(iclog->ic_header.h_num_logops, ARCH_CONVERT, ops); + + bp = iclog->ic_bp; + ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == (unsigned long)1); + XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)2); + XFS_BUF_SET_ADDR(bp, BLOCK_LSN(INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT))); + + XFS_STATS_ADD(xs_log_blocks, BTOBB(count)); + + /* Do we need to split this write into 2 parts? */ + if (XFS_BUF_ADDR(bp) + BTOBB(count) > log->l_logBBsize) { + split = count - (BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp))); + count = BBTOB(log->l_logBBsize - XFS_BUF_ADDR(bp)); + iclog->ic_bwritecnt = 2; /* split into 2 writes */ + } else { + iclog->ic_bwritecnt = 1; + } + XFS_BUF_SET_PTR(bp, (xfs_caddr_t) &(iclog->ic_header), count); + XFS_BUF_SET_FSPRIVATE(bp, iclog); /* save for later */ + XFS_BUF_BUSY(bp); + XFS_BUF_ASYNC(bp); + /* + * Do a disk write cache flush for the log block. + * This is a bit of a sledgehammer, it would be better + * to use a tag barrier here that just prevents reordering. + * It may not be needed to flush the first split block in the log wrap + * case, but do it anyways to be safe -AK + */ + if (!(log->l_mp->m_flags & XFS_MOUNT_NOLOGFLUSH)) + XFS_BUF_FLUSH(bp); + + ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); + ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); + + xlog_verify_iclog(log, iclog, count, B_TRUE); + + /* account for log which doesn't start at block #0 */ + XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); + /* + * Don't call xfs_bwrite here. We do log-syncs even when the filesystem + * is shutting down. + */ + XFS_BUF_WRITE(bp); + + if ((error = XFS_bwrite(bp))) { + xfs_ioerror_alert("xlog_sync", log->l_mp, bp, + XFS_BUF_ADDR(bp)); + return (error); + } + if (split) { + bp = iclog->ic_log->l_xbuf; + ASSERT(XFS_BUF_FSPRIVATE2(bp, unsigned long) == + (unsigned long)1); + XFS_BUF_SET_FSPRIVATE2(bp, (unsigned long)2); + XFS_BUF_SET_ADDR(bp, 0); /* logical 0 */ + XFS_BUF_SET_PTR(bp, (xfs_caddr_t)((__psint_t)&(iclog->ic_header)+ + (__psint_t)count), split); + XFS_BUF_SET_FSPRIVATE(bp, iclog); + XFS_BUF_BUSY(bp); + XFS_BUF_ASYNC(bp); + if (!(log->l_mp->m_flags & XFS_MOUNT_NOLOGFLUSH)) + XFS_BUF_FLUSH(bp); + dptr = XFS_BUF_PTR(bp); + /* + * Bump the cycle numbers at the start of each block + * since this part of the buffer is at the start of + * a new cycle. Watch out for the header magic number + * case, though. + */ + for (i=0; i<split; i += BBSIZE) { + INT_MOD(*(uint *)dptr, ARCH_CONVERT, +1); + if (INT_GET(*(uint *)dptr, ARCH_CONVERT) == XLOG_HEADER_MAGIC_NUM) + INT_MOD(*(uint *)dptr, ARCH_CONVERT, +1); + dptr += BBSIZE; + } + + ASSERT(XFS_BUF_ADDR(bp) <= log->l_logBBsize-1); + ASSERT(XFS_BUF_ADDR(bp) + BTOBB(count) <= log->l_logBBsize); + + /* account for internal log which does't start at block #0 */ + XFS_BUF_SET_ADDR(bp, XFS_BUF_ADDR(bp) + log->l_logBBstart); + XFS_BUF_WRITE(bp); + if ((error = XFS_bwrite(bp))) { + xfs_ioerror_alert("xlog_sync (split)", log->l_mp, + bp, XFS_BUF_ADDR(bp)); + return (error); + } + } + return (0); +} /* xlog_sync */ + + +/* + * Unallocate a log structure + */ +void +xlog_unalloc_log(xlog_t *log) +{ + xlog_in_core_t *iclog, *next_iclog; + xlog_ticket_t *tic, *next_tic; + int i; + + + iclog = log->l_iclog; + for (i=0; i<log->l_iclog_bufs; i++) { + sv_destroy(&iclog->ic_forcesema); + sv_destroy(&iclog->ic_writesema); + xfs_buf_free(iclog->ic_bp); +#ifdef XFS_LOG_TRACE + if (iclog->ic_trace != NULL) { + ktrace_free(iclog->ic_trace); + } +#endif + next_iclog = iclog->ic_next; + kmem_free(iclog->hic_data, log->l_iclog_size); + kmem_free(iclog, sizeof(xlog_in_core_t)); + iclog = next_iclog; + } + freesema(&log->l_flushsema); + spinlock_destroy(&log->l_icloglock); + spinlock_destroy(&log->l_grant_lock); + + /* XXXsup take a look at this again. */ + if ((log->l_ticket_cnt != log->l_ticket_tcnt) && + !XLOG_FORCED_SHUTDOWN(log)) { + xfs_fs_cmn_err(CE_WARN, log->l_mp, + "xlog_unalloc_log: (cnt: %d, total: %d)", + log->l_ticket_cnt, log->l_ticket_tcnt); + /* ASSERT(log->l_ticket_cnt == log->l_ticket_tcnt); */ + + } else { + tic = log->l_unmount_free; + while (tic) { + next_tic = tic->t_next; + kmem_free(tic, NBPP); + tic = next_tic; + } + } + xfs_buf_free(log->l_xbuf); +#ifdef XFS_LOG_TRACE + if (log->l_trace != NULL) { + ktrace_free(log->l_trace); + } + if (log->l_grant_trace != NULL) { + ktrace_free(log->l_grant_trace); + } +#endif + log->l_mp->m_log = NULL; + kmem_free(log, sizeof(xlog_t)); +} /* xlog_unalloc_log */ + +/* + * Update counters atomically now that memcpy is done. + */ +/* ARGSUSED */ +static inline void +xlog_state_finish_copy(xlog_t *log, + xlog_in_core_t *iclog, + int record_cnt, + int copy_bytes) +{ + SPLDECL(s); + + s = LOG_LOCK(log); + + iclog->ic_header.h_num_logops += record_cnt; + iclog->ic_offset += copy_bytes; + + LOG_UNLOCK(log, s); +} /* xlog_state_finish_copy */ + + + + +/* + * Write some region out to in-core log + * + * This will be called when writing externally provided regions or when + * writing out a commit record for a given transaction. + * + * General algorithm: + * 1. Find total length of this write. This may include adding to the + * lengths passed in. + * 2. Check whether we violate the tickets reservation. + * 3. While writing to this iclog + * A. Reserve as much space in this iclog as can get + * B. If this is first write, save away start lsn + * C. While writing this region: + * 1. If first write of transaction, write start record + * 2. Write log operation header (header per region) + * 3. Find out if we can fit entire region into this iclog + * 4. Potentially, verify destination memcpy ptr + * 5. Memcpy (partial) region + * 6. If partial copy, release iclog; otherwise, continue + * copying more regions into current iclog + * 4. Mark want sync bit (in simulation mode) + * 5. Release iclog for potential flush to on-disk log. + * + * ERRORS: + * 1. Panic if reservation is overrun. This should never happen since + * reservation amounts are generated internal to the filesystem. + * NOTES: + * 1. Tickets are single threaded data structures. + * 2. The XLOG_END_TRANS & XLOG_CONTINUE_TRANS flags are passed down to the + * syncing routine. When a single log_write region needs to span + * multiple in-core logs, the XLOG_CONTINUE_TRANS bit should be set + * on all log operation writes which don't contain the end of the + * region. The XLOG_END_TRANS bit is used for the in-core log + * operation which contains the end of the continued log_write region. + * 3. When xlog_state_get_iclog_space() grabs the rest of the current iclog, + * we don't really know exactly how much space will be used. As a result, + * we don't update ic_offset until the end when we know exactly how many + * bytes have been written out. + */ +int +xlog_write(xfs_mount_t * mp, + xfs_log_iovec_t reg[], + int nentries, + xfs_log_ticket_t tic, + xfs_lsn_t *start_lsn, + xlog_in_core_t **commit_iclog, + uint flags) +{ + xlog_t *log = mp->m_log; + xlog_ticket_t *ticket = (xlog_ticket_t *)tic; + xlog_op_header_t *logop_head; /* ptr to log operation header */ + xlog_in_core_t *iclog; /* ptr to current in-core log */ + __psint_t ptr; /* copy address into data region */ + int len; /* # xlog_write() bytes 2 still copy */ + int index; /* region index currently copying */ + int log_offset; /* offset (from 0) into data region */ + int start_rec_copy; /* # bytes to copy for start record */ + int partial_copy; /* did we split a region? */ + int partial_copy_len;/* # bytes copied if split region */ + int need_copy; /* # bytes need to memcpy this region */ + int copy_len; /* # bytes actually memcpy'ing */ + int copy_off; /* # bytes from entry start */ + int contwr; /* continued write of in-core log? */ + int error; + int record_cnt = 0, data_cnt = 0; + + partial_copy_len = partial_copy = 0; + + /* Calculate potential maximum space. Each region gets its own + * xlog_op_header_t and may need to be double word aligned. + */ + len = 0; + if (ticket->t_flags & XLOG_TIC_INITED) /* acct for start rec of xact */ + len += sizeof(xlog_op_header_t); + + for (index = 0; index < nentries; index++) { + len += sizeof(xlog_op_header_t); /* each region gets >= 1 */ + len += reg[index].i_len; + } + contwr = *start_lsn = 0; + + if (ticket->t_curr_res < len) { +#ifdef DEBUG + xlog_panic( + "xfs_log_write: reservation ran out. Need to up reservation"); +#else + /* Customer configurable panic */ + xfs_cmn_err(XFS_PTAG_LOGRES, CE_ALERT, mp, + "xfs_log_write: reservation ran out. Need to up reservation"); + /* If we did not panic, shutdown the filesystem */ + xfs_force_shutdown(mp, XFS_CORRUPT_INCORE); +#endif + } else + ticket->t_curr_res -= len; + + for (index = 0; index < nentries; ) { + if ((error = xlog_state_get_iclog_space(log, len, &iclog, ticket, + &contwr, &log_offset))) + return (error); + + ASSERT(log_offset <= iclog->ic_size - 1); + ptr = (__psint_t) ((char *)iclog->ic_datap+log_offset); + + /* start_lsn is the first lsn written to. That's all we need. */ + if (! *start_lsn) + *start_lsn = INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT); + + /* This loop writes out as many regions as can fit in the amount + * of space which was allocated by xlog_state_get_iclog_space(). + */ + while (index < nentries) { + ASSERT(reg[index].i_len % sizeof(__int32_t) == 0); + ASSERT((__psint_t)ptr % sizeof(__int32_t) == 0); + start_rec_copy = 0; + + /* If first write for transaction, insert start record. + * We can't be trying to commit if we are inited. We can't + * have any "partial_copy" if we are inited. + */ + if (ticket->t_flags & XLOG_TIC_INITED) { + logop_head = (xlog_op_header_t *)ptr; + INT_SET(logop_head->oh_tid, ARCH_CONVERT, ticket->t_tid); + logop_head->oh_clientid = ticket->t_clientid; + logop_head->oh_len = 0; + logop_head->oh_flags = XLOG_START_TRANS; + logop_head->oh_res2 = 0; + ticket->t_flags &= ~XLOG_TIC_INITED; /* clear bit */ + record_cnt++; + + start_rec_copy = sizeof(xlog_op_header_t); + xlog_write_adv_cnt(ptr, len, log_offset, start_rec_copy); + } + + /* Copy log operation header directly into data section */ + logop_head = (xlog_op_header_t *)ptr; + INT_SET(logop_head->oh_tid, ARCH_CONVERT, ticket->t_tid); + logop_head->oh_clientid = ticket->t_clientid; + logop_head->oh_res2 = 0; + + /* header copied directly */ + xlog_write_adv_cnt(ptr, len, log_offset, sizeof(xlog_op_header_t)); + + /* are we copying a commit or unmount record? */ + logop_head->oh_flags = flags; + + /* + * We've seen logs corrupted with bad transaction client + * ids. This makes sure that XFS doesn't generate them on. + * Turn this into an EIO and shut down the filesystem. + */ + switch (logop_head->oh_clientid) { + case XFS_TRANSACTION: + case XFS_VOLUME: + case XFS_LOG: + break; + default: + xfs_fs_cmn_err(CE_WARN, mp, + "Bad XFS transaction clientid 0x%x in ticket 0x%p", + logop_head->oh_clientid, tic); + return XFS_ERROR(EIO); + } + + /* Partial write last time? => (partial_copy != 0) + * need_copy is the amount we'd like to copy if everything could + * fit in the current memcpy. + */ + need_copy = reg[index].i_len - partial_copy_len; + + copy_off = partial_copy_len; + if (need_copy <= iclog->ic_size - log_offset) { /*complete write */ + INT_SET(logop_head->oh_len, ARCH_CONVERT, copy_len = need_copy); + if (partial_copy) + logop_head->oh_flags|= (XLOG_END_TRANS|XLOG_WAS_CONT_TRANS); + partial_copy_len = partial_copy = 0; + } else { /* partial write */ + copy_len = iclog->ic_size - log_offset; + INT_SET(logop_head->oh_len, ARCH_CONVERT, copy_len); + logop_head->oh_flags |= XLOG_CONTINUE_TRANS; + if (partial_copy) + logop_head->oh_flags |= XLOG_WAS_CONT_TRANS; + partial_copy_len += copy_len; + partial_copy++; + len += sizeof(xlog_op_header_t); /* from splitting of region */ + /* account for new log op header */ + ticket->t_curr_res -= sizeof(xlog_op_header_t); + } + xlog_verify_dest_ptr(log, ptr); + + /* copy region */ + ASSERT(copy_len >= 0); + memcpy((xfs_caddr_t)ptr, reg[index].i_addr + copy_off, copy_len); + xlog_write_adv_cnt(ptr, len, log_offset, copy_len); + + /* make copy_len total bytes copied, including headers */ + copy_len += start_rec_copy + sizeof(xlog_op_header_t); + record_cnt++; + data_cnt += contwr ? copy_len : 0; + if (partial_copy) { /* copied partial region */ + /* already marked WANT_SYNC by xlog_state_get_iclog_space */ + xlog_state_finish_copy(log, iclog, record_cnt, data_cnt); + record_cnt = data_cnt = 0; + if ((error = xlog_state_release_iclog(log, iclog))) + return (error); + break; /* don't increment index */ + } else { /* copied entire region */ + index++; + partial_copy_len = partial_copy = 0; + + if (iclog->ic_size - log_offset <= sizeof(xlog_op_header_t)) { + xlog_state_finish_copy(log, iclog, record_cnt, data_cnt); + record_cnt = data_cnt = 0; + xlog_state_want_sync(log, iclog); + if (commit_iclog) { + ASSERT(flags & XLOG_COMMIT_TRANS); + *commit_iclog = iclog; + } else if ((error = xlog_state_release_iclog(log, iclog))) + return (error); + if (index == nentries) + return 0; /* we are done */ + else + break; + } + } /* if (partial_copy) */ + } /* while (index < nentries) */ + } /* for (index = 0; index < nentries; ) */ + ASSERT(len == 0); + + xlog_state_finish_copy(log, iclog, record_cnt, data_cnt); + if (commit_iclog) { + ASSERT(flags & XLOG_COMMIT_TRANS); + *commit_iclog = iclog; + return 0; + } + return (xlog_state_release_iclog(log, iclog)); +} /* xlog_write */ + + +/***************************************************************************** + * + * State Machine functions + * + ***************************************************************************** + */ + +/* Clean iclogs starting from the head. This ordering must be + * maintained, so an iclog doesn't become ACTIVE beyond one that + * is SYNCING. This is also required to maintain the notion that we use + * a counting semaphore to hold off would be writers to the log when every + * iclog is trying to sync to disk. + * + * State Change: DIRTY -> ACTIVE + */ +void +xlog_state_clean_log(xlog_t *log) +{ + xlog_in_core_t *iclog; + int changed = 0; + + iclog = log->l_iclog; + do { + if (iclog->ic_state == XLOG_STATE_DIRTY) { + iclog->ic_state = XLOG_STATE_ACTIVE; + iclog->ic_offset = 0; + iclog->ic_callback = NULL; /* don't need to free */ + /* + * If the number of ops in this iclog indicate it just + * contains the dummy transaction, we can + * change state into IDLE (the second time around). + * Otherwise we should change the state into + * NEED a dummy. + * We don't need to cover the dummy. + */ + if (!changed && + (INT_GET(iclog->ic_header.h_num_logops, ARCH_CONVERT) == XLOG_COVER_OPS)) { + changed = 1; + } else { + /* + * We have two dirty iclogs so start over + * This could also be num of ops indicates + * this is not the dummy going out. + */ + changed = 2; + } + iclog->ic_header.h_num_logops = 0; + memset(iclog->ic_header.h_cycle_data, 0, + sizeof(iclog->ic_header.h_cycle_data)); + iclog->ic_header.h_lsn = 0; + } else if (iclog->ic_state == XLOG_STATE_ACTIVE) + /* do nothing */; + else + break; /* stop cleaning */ + iclog = iclog->ic_next; + } while (iclog != log->l_iclog); + + /* log is locked when we are called */ + /* + * Change state for the dummy log recording. + * We usually go to NEED. But we go to NEED2 if the changed indicates + * we are done writing the dummy record. + * If we are done with the second dummy recored (DONE2), then + * we go to IDLE. + */ + if (changed) { + switch (log->l_covered_state) { + case XLOG_STATE_COVER_IDLE: + case XLOG_STATE_COVER_NEED: + case XLOG_STATE_COVER_NEED2: + log->l_covered_state = XLOG_STATE_COVER_NEED; + break; + + case XLOG_STATE_COVER_DONE: + if (changed == 1) + log->l_covered_state = XLOG_STATE_COVER_NEED2; + else + log->l_covered_state = XLOG_STATE_COVER_NEED; + break; + + case XLOG_STATE_COVER_DONE2: + if (changed == 1) + log->l_covered_state = XLOG_STATE_COVER_IDLE; + else + log->l_covered_state = XLOG_STATE_COVER_NEED; + break; + + default: + ASSERT(0); + } + } +} /* xlog_state_clean_log */ + +STATIC xfs_lsn_t +xlog_get_lowest_lsn( + xlog_t *log) +{ + xlog_in_core_t *lsn_log; + xfs_lsn_t lowest_lsn, lsn; + + lsn_log = log->l_iclog; + lowest_lsn = 0; + do { + if (!(lsn_log->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY))) { + lsn = INT_GET(lsn_log->ic_header.h_lsn, ARCH_CONVERT); + if ((lsn && !lowest_lsn) || + (XFS_LSN_CMP(lsn, lowest_lsn) < 0)) { + lowest_lsn = lsn; + } + } + lsn_log = lsn_log->ic_next; + } while (lsn_log != log->l_iclog); + return(lowest_lsn); +} + + +STATIC void +xlog_state_do_callback( + xlog_t *log, + int aborted, + xlog_in_core_t *ciclog) +{ + xlog_in_core_t *iclog; + xlog_in_core_t *first_iclog; /* used to know when we've + * processed all iclogs once */ + xfs_log_callback_t *cb, *cb_next; + int flushcnt = 0; + xfs_lsn_t lowest_lsn; + int ioerrors; /* counter: iclogs with errors */ + int loopdidcallbacks; /* flag: inner loop did callbacks*/ + int funcdidcallbacks; /* flag: function did callbacks */ + int repeats; /* for issuing console warnings if + * looping too many times */ + SPLDECL(s); + + s = LOG_LOCK(log); + first_iclog = iclog = log->l_iclog; + ioerrors = 0; + funcdidcallbacks = 0; + repeats = 0; + + do { + /* + * Scan all iclogs starting with the one pointed to by the + * log. Reset this starting point each time the log is + * unlocked (during callbacks). + * + * Keep looping through iclogs until one full pass is made + * without running any callbacks. + */ + first_iclog = log->l_iclog; + iclog = log->l_iclog; + loopdidcallbacks = 0; + repeats++; + + do { + + /* skip all iclogs in the ACTIVE & DIRTY states */ + if (iclog->ic_state & + (XLOG_STATE_ACTIVE|XLOG_STATE_DIRTY)) { + iclog = iclog->ic_next; + continue; + } + + /* + * Between marking a filesystem SHUTDOWN and stopping + * the log, we do flush all iclogs to disk (if there + * wasn't a log I/O error). So, we do want things to + * go smoothly in case of just a SHUTDOWN w/o a + * LOG_IO_ERROR. + */ + if (!(iclog->ic_state & XLOG_STATE_IOERROR)) { + /* + * Can only perform callbacks in order. Since + * this iclog is not in the DONE_SYNC/ + * DO_CALLBACK state, we skip the rest and + * just try to clean up. If we set our iclog + * to DO_CALLBACK, we will not process it when + * we retry since a previous iclog is in the + * CALLBACK and the state cannot change since + * we are holding the LOG_LOCK. + */ + if (!(iclog->ic_state & + (XLOG_STATE_DONE_SYNC | + XLOG_STATE_DO_CALLBACK))) { + if (ciclog && (ciclog->ic_state == + XLOG_STATE_DONE_SYNC)) { + ciclog->ic_state = XLOG_STATE_DO_CALLBACK; + } + break; + } + /* + * We now have an iclog that is in either the + * DO_CALLBACK or DONE_SYNC states. The other + * states (WANT_SYNC, SYNCING, or CALLBACK were + * caught by the above if and are going to + * clean (i.e. we aren't doing their callbacks) + * see the above if. + */ + + /* + * We will do one more check here to see if we + * have chased our tail around. + */ + + lowest_lsn = xlog_get_lowest_lsn(log); + if (lowest_lsn && ( + XFS_LSN_CMP( + lowest_lsn, + INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT) + )<0)) { + iclog = iclog->ic_next; + continue; /* Leave this iclog for + * another thread */ + } + + iclog->ic_state = XLOG_STATE_CALLBACK; + + LOG_UNLOCK(log, s); + + /* l_last_sync_lsn field protected by + * GRANT_LOCK. Don't worry about iclog's lsn. + * No one else can be here except us. + */ + s = GRANT_LOCK(log); + ASSERT(XFS_LSN_CMP( + log->l_last_sync_lsn, + INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT) + )<=0); + log->l_last_sync_lsn = INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT); + GRANT_UNLOCK(log, s); + + /* + * Keep processing entries in the callback list + * until we come around and it is empty. We + * need to atomically see that the list is + * empty and change the state to DIRTY so that + * we don't miss any more callbacks being added. + */ + s = LOG_LOCK(log); + } else { + ioerrors++; + } + cb = iclog->ic_callback; + + while (cb != 0) { + iclog->ic_callback_tail = &(iclog->ic_callback); + iclog->ic_callback = NULL; + LOG_UNLOCK(log, s); + + /* perform callbacks in the order given */ + for (; cb != 0; cb = cb_next) { + cb_next = cb->cb_next; + cb->cb_func(cb->cb_arg, aborted); + } + s = LOG_LOCK(log); + cb = iclog->ic_callback; + } + + loopdidcallbacks++; + funcdidcallbacks++; + + ASSERT(iclog->ic_callback == 0); + if (!(iclog->ic_state & XLOG_STATE_IOERROR)) + iclog->ic_state = XLOG_STATE_DIRTY; + + /* + * Transition from DIRTY to ACTIVE if applicable. + * NOP if STATE_IOERROR. + */ + xlog_state_clean_log(log); + + /* wake up threads waiting in xfs_log_force() */ + sv_broadcast(&iclog->ic_forcesema); + + iclog = iclog->ic_next; + } while (first_iclog != iclog); + if (repeats && (repeats % 10) == 0) { + xfs_fs_cmn_err(CE_WARN, log->l_mp, + "xlog_state_do_callback: looping %d", repeats); + } + } while (!ioerrors && loopdidcallbacks); + + /* + * make one last gasp attempt to see if iclogs are being left in + * limbo.. + */ +#ifdef DEBUG + if (funcdidcallbacks) { + first_iclog = iclog = log->l_iclog; + do { + ASSERT(iclog->ic_state != XLOG_STATE_DO_CALLBACK); + /* + * Terminate the loop if iclogs are found in states + * which will cause other threads to clean up iclogs. + * + * SYNCING - i/o completion will go through logs + * DONE_SYNC - interrupt thread should be waiting for + * LOG_LOCK + * IOERROR - give up hope all ye who enter here + */ + if (iclog->ic_state == XLOG_STATE_WANT_SYNC || + iclog->ic_state == XLOG_STATE_SYNCING || + iclog->ic_state == XLOG_STATE_DONE_SYNC || + iclog->ic_state == XLOG_STATE_IOERROR ) + break; + iclog = iclog->ic_next; + } while (first_iclog != iclog); + } +#endif + + if (log->l_iclog->ic_state & (XLOG_STATE_ACTIVE|XLOG_STATE_IOERROR)) { + flushcnt = log->l_flushcnt; + log->l_flushcnt = 0; + } + LOG_UNLOCK(log, s); + while (flushcnt--) + vsema(&log->l_flushsema); +} /* xlog_state_do_callback */ + + +/* + * Finish transitioning this iclog to the dirty state. + * + * Make sure that we completely execute this routine only when this is + * the last call to the iclog. There is a good chance that iclog flushes, + * when we reach the end of the physical log, get turned into 2 separate + * calls to bwrite. Hence, one iclog flush could generate two calls to this + * routine. By using the reference count bwritecnt, we guarantee that only + * the second completion goes through. + * + * Callbacks could take time, so they are done outside the scope of the + * global state machine log lock. Assume that the calls to cvsema won't + * take a long time. At least we know it won't sleep. + */ +void +xlog_state_done_syncing( + xlog_in_core_t *iclog, + int aborted) +{ + xlog_t *log = iclog->ic_log; + SPLDECL(s); + + s = LOG_LOCK(log); + + ASSERT(iclog->ic_state == XLOG_STATE_SYNCING || + iclog->ic_state == XLOG_STATE_IOERROR); + ASSERT(iclog->ic_refcnt == 0); + ASSERT(iclog->ic_bwritecnt == 1 || iclog->ic_bwritecnt == 2); + + + /* + * If we got an error, either on the first buffer, or in the case of + * split log writes, on the second, we mark ALL iclogs STATE_IOERROR, + * and none should ever be attempted to be written to disk + * again. + */ + if (iclog->ic_state != XLOG_STATE_IOERROR) { + if (--iclog->ic_bwritecnt == 1) { + LOG_UNLOCK(log, s); + return; + } + iclog->ic_state = XLOG_STATE_DONE_SYNC; + } + + /* + * Someone could be sleeping prior to writing out the next + * iclog buffer, we wake them all, one will get to do the + * I/O, the others get to wait for the result. + */ + sv_broadcast(&iclog->ic_writesema); + LOG_UNLOCK(log, s); + xlog_state_do_callback(log, aborted, iclog); /* also cleans log */ +} /* xlog_state_done_syncing */ + + +/* + * If the head of the in-core log ring is not (ACTIVE or DIRTY), then we must + * sleep. The flush semaphore is set to the number of in-core buffers and + * decremented around disk syncing. Therefore, if all buffers are syncing, + * this semaphore will cause new writes to sleep until a sync completes. + * Otherwise, this code just does p() followed by v(). This approximates + * a sleep/wakeup except we can't race. + * + * The in-core logs are used in a circular fashion. They are not used + * out-of-order even when an iclog past the head is free. + * + * return: + * * log_offset where xlog_write() can start writing into the in-core + * log's data space. + * * in-core log pointer to which xlog_write() should write. + * * boolean indicating this is a continued write to an in-core log. + * If this is the last write, then the in-core log's offset field + * needs to be incremented, depending on the amount of data which + * is copied. + */ +int +xlog_state_get_iclog_space(xlog_t *log, + int len, + xlog_in_core_t **iclogp, + xlog_ticket_t *ticket, + int *continued_write, + int *logoffsetp) +{ + SPLDECL(s); + int log_offset; + xlog_rec_header_t *head; + xlog_in_core_t *iclog; + int error; + +restart: + s = LOG_LOCK(log); + if (XLOG_FORCED_SHUTDOWN(log)) { + LOG_UNLOCK(log, s); + return XFS_ERROR(EIO); + } + + iclog = log->l_iclog; + if (! (iclog->ic_state == XLOG_STATE_ACTIVE)) { + log->l_flushcnt++; + LOG_UNLOCK(log, s); + xlog_trace_iclog(iclog, XLOG_TRACE_SLEEP_FLUSH); + XFS_STATS_INC(xs_log_noiclogs); + /* Ensure that log writes happen */ + psema(&log->l_flushsema, PINOD); + goto restart; + } + ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE); + head = &iclog->ic_header; + + iclog->ic_refcnt++; /* prevents sync */ + log_offset = iclog->ic_offset; + + /* On the 1st write to an iclog, figure out lsn. This works + * if iclogs marked XLOG_STATE_WANT_SYNC always write out what they are + * committing to. If the offset is set, that's how many blocks + * must be written. + */ + if (log_offset == 0) { + ticket->t_curr_res -= log->l_iclog_hsize; + INT_SET(head->h_cycle, ARCH_CONVERT, log->l_curr_cycle); + ASSIGN_LSN(head->h_lsn, log); + ASSERT(log->l_curr_block >= 0); + } + + /* If there is enough room to write everything, then do it. Otherwise, + * claim the rest of the region and make sure the XLOG_STATE_WANT_SYNC + * bit is on, so this will get flushed out. Don't update ic_offset + * until you know exactly how many bytes get copied. Therefore, wait + * until later to update ic_offset. + * + * xlog_write() algorithm assumes that at least 2 xlog_op_header_t's + * can fit into remaining data section. + */ + if (iclog->ic_size - iclog->ic_offset < 2*sizeof(xlog_op_header_t)) { + xlog_state_switch_iclogs(log, iclog, iclog->ic_size); + + /* If I'm the only one writing to this iclog, sync it to disk */ + if (iclog->ic_refcnt == 1) { + LOG_UNLOCK(log, s); + if ((error = xlog_state_release_iclog(log, iclog))) + return (error); + } else { + iclog->ic_refcnt--; + LOG_UNLOCK(log, s); + } + goto restart; + } + + /* Do we have enough room to write the full amount in the remainder + * of this iclog? Or must we continue a write on the next iclog and + * mark this iclog as completely taken? In the case where we switch + * iclogs (to mark it taken), this particular iclog will release/sync + * to disk in xlog_write(). + */ + if (len <= iclog->ic_size - iclog->ic_offset) { + *continued_write = 0; + iclog->ic_offset += len; + } else { + *continued_write = 1; + xlog_state_switch_iclogs(log, iclog, iclog->ic_size); + } + *iclogp = iclog; + + ASSERT(iclog->ic_offset <= iclog->ic_size); + LOG_UNLOCK(log, s); + + *logoffsetp = log_offset; + return 0; +} /* xlog_state_get_iclog_space */ + +/* + * Atomically get the log space required for a log ticket. + * + * Once a ticket gets put onto the reserveq, it will only return after + * the needed reservation is satisfied. + */ +STATIC int +xlog_grant_log_space(xlog_t *log, + xlog_ticket_t *tic) +{ + int free_bytes; + int need_bytes; + SPLDECL(s); +#ifdef DEBUG + xfs_lsn_t tail_lsn; +#endif + + +#ifdef DEBUG + if (log->l_flags & XLOG_ACTIVE_RECOVERY) + panic("grant Recovery problem"); +#endif + + /* Is there space or do we need to sleep? */ + s = GRANT_LOCK(log); + xlog_trace_loggrant(log, tic, "xlog_grant_log_space: enter"); + + /* something is already sleeping; insert new transaction at end */ + if (log->l_reserve_headq) { + XLOG_INS_TICKETQ(log->l_reserve_headq, tic); + xlog_trace_loggrant(log, tic, + "xlog_grant_log_space: sleep 1"); + /* + * Gotta check this before going to sleep, while we're + * holding the grant lock. + */ + if (XLOG_FORCED_SHUTDOWN(log)) + goto error_return; + + XFS_STATS_INC(xs_sleep_logspace); + sv_wait(&tic->t_sema, PINOD|PLTWAIT, &log->l_grant_lock, s); + /* + * If we got an error, and the filesystem is shutting down, + * we'll catch it down below. So just continue... + */ + xlog_trace_loggrant(log, tic, + "xlog_grant_log_space: wake 1"); + s = GRANT_LOCK(log); + } + if (tic->t_flags & XFS_LOG_PERM_RESERV) + need_bytes = tic->t_unit_res*tic->t_ocnt; + else + need_bytes = tic->t_unit_res; + +redo: + if (XLOG_FORCED_SHUTDOWN(log)) + goto error_return; + + free_bytes = xlog_space_left(log, log->l_grant_reserve_cycle, + log->l_grant_reserve_bytes); + if (free_bytes < need_bytes) { + if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) + XLOG_INS_TICKETQ(log->l_reserve_headq, tic); + xlog_trace_loggrant(log, tic, + "xlog_grant_log_space: sleep 2"); + XFS_STATS_INC(xs_sleep_logspace); + sv_wait(&tic->t_sema, PINOD|PLTWAIT, &log->l_grant_lock, s); + + if (XLOG_FORCED_SHUTDOWN(log)) { + s = GRANT_LOCK(log); + goto error_return; + } + + xlog_trace_loggrant(log, tic, + "xlog_grant_log_space: wake 2"); + xlog_grant_push_ail(log->l_mp, need_bytes); + s = GRANT_LOCK(log); + goto redo; + } else if (tic->t_flags & XLOG_TIC_IN_Q) + XLOG_DEL_TICKETQ(log->l_reserve_headq, tic); + + /* we've got enough space */ + XLOG_GRANT_ADD_SPACE(log, need_bytes, 'w'); + XLOG_GRANT_ADD_SPACE(log, need_bytes, 'r'); +#ifdef DEBUG + tail_lsn = log->l_tail_lsn; + /* + * Check to make sure the grant write head didn't just over lap the + * tail. If the cycles are the same, we can't be overlapping. + * Otherwise, make sure that the cycles differ by exactly one and + * check the byte count. + */ + if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) { + ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn)); + ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn))); + } +#endif + xlog_trace_loggrant(log, tic, "xlog_grant_log_space: exit"); + xlog_verify_grant_head(log, 1); + GRANT_UNLOCK(log, s); + return 0; + + error_return: + if (tic->t_flags & XLOG_TIC_IN_Q) + XLOG_DEL_TICKETQ(log->l_reserve_headq, tic); + xlog_trace_loggrant(log, tic, "xlog_grant_log_space: err_ret"); + /* + * If we are failing, make sure the ticket doesn't have any + * current reservations. We don't want to add this back when + * the ticket/transaction gets cancelled. + */ + tic->t_curr_res = 0; + tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ + GRANT_UNLOCK(log, s); + return XFS_ERROR(EIO); +} /* xlog_grant_log_space */ + + +/* + * Replenish the byte reservation required by moving the grant write head. + * + * + */ +STATIC int +xlog_regrant_write_log_space(xlog_t *log, + xlog_ticket_t *tic) +{ + SPLDECL(s); + int free_bytes, need_bytes; + xlog_ticket_t *ntic; +#ifdef DEBUG + xfs_lsn_t tail_lsn; +#endif + + tic->t_curr_res = tic->t_unit_res; + + if (tic->t_cnt > 0) + return (0); + +#ifdef DEBUG + if (log->l_flags & XLOG_ACTIVE_RECOVERY) + panic("regrant Recovery problem"); +#endif + + s = GRANT_LOCK(log); + xlog_trace_loggrant(log, tic, "xlog_regrant_write_log_space: enter"); + + if (XLOG_FORCED_SHUTDOWN(log)) + goto error_return; + + /* If there are other waiters on the queue then give them a + * chance at logspace before us. Wake up the first waiters, + * if we do not wake up all the waiters then go to sleep waiting + * for more free space, otherwise try to get some space for + * this transaction. + */ + + if ((ntic = log->l_write_headq)) { + free_bytes = xlog_space_left(log, log->l_grant_write_cycle, + log->l_grant_write_bytes); + do { + ASSERT(ntic->t_flags & XLOG_TIC_PERM_RESERV); + + if (free_bytes < ntic->t_unit_res) + break; + free_bytes -= ntic->t_unit_res; + sv_signal(&ntic->t_sema); + ntic = ntic->t_next; + } while (ntic != log->l_write_headq); + + if (ntic != log->l_write_headq) { + if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) + XLOG_INS_TICKETQ(log->l_write_headq, tic); + + xlog_trace_loggrant(log, tic, + "xlog_regrant_write_log_space: sleep 1"); + XFS_STATS_INC(xs_sleep_logspace); + sv_wait(&tic->t_sema, PINOD|PLTWAIT, + &log->l_grant_lock, s); + + /* If we're shutting down, this tic is already + * off the queue */ + if (XLOG_FORCED_SHUTDOWN(log)) { + s = GRANT_LOCK(log); + goto error_return; + } + + xlog_trace_loggrant(log, tic, + "xlog_regrant_write_log_space: wake 1"); + xlog_grant_push_ail(log->l_mp, tic->t_unit_res); + s = GRANT_LOCK(log); + } + } + + need_bytes = tic->t_unit_res; + +redo: + if (XLOG_FORCED_SHUTDOWN(log)) + goto error_return; + + free_bytes = xlog_space_left(log, log->l_grant_write_cycle, + log->l_grant_write_bytes); + if (free_bytes < need_bytes) { + if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) + XLOG_INS_TICKETQ(log->l_write_headq, tic); + XFS_STATS_INC(xs_sleep_logspace); + sv_wait(&tic->t_sema, PINOD|PLTWAIT, &log->l_grant_lock, s); + + /* If we're shutting down, this tic is already off the queue */ + if (XLOG_FORCED_SHUTDOWN(log)) { + s = GRANT_LOCK(log); + goto error_return; + } + + xlog_trace_loggrant(log, tic, + "xlog_regrant_write_log_space: wake 2"); + xlog_grant_push_ail(log->l_mp, need_bytes); + s = GRANT_LOCK(log); + goto redo; + } else if (tic->t_flags & XLOG_TIC_IN_Q) + XLOG_DEL_TICKETQ(log->l_write_headq, tic); + + XLOG_GRANT_ADD_SPACE(log, need_bytes, 'w'); /* we've got enough space */ +#ifdef DEBUG + tail_lsn = log->l_tail_lsn; + if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) { + ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn)); + ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn))); + } +#endif + + xlog_trace_loggrant(log, tic, "xlog_regrant_write_log_space: exit"); + xlog_verify_grant_head(log, 1); + GRANT_UNLOCK(log, s); + return (0); + + + error_return: + if (tic->t_flags & XLOG_TIC_IN_Q) + XLOG_DEL_TICKETQ(log->l_reserve_headq, tic); + xlog_trace_loggrant(log, tic, "xlog_regrant_write_log_space: err_ret"); + /* + * If we are failing, make sure the ticket doesn't have any + * current reservations. We don't want to add this back when + * the ticket/transaction gets cancelled. + */ + tic->t_curr_res = 0; + tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ + GRANT_UNLOCK(log, s); + return XFS_ERROR(EIO); +} /* xlog_regrant_write_log_space */ + + +/* The first cnt-1 times through here we don't need to + * move the grant write head because the permanent + * reservation has reserved cnt times the unit amount. + * Release part of current permanent unit reservation and + * reset current reservation to be one units worth. Also + * move grant reservation head forward. + */ +STATIC void +xlog_regrant_reserve_log_space(xlog_t *log, + xlog_ticket_t *ticket) +{ + SPLDECL(s); + + xlog_trace_loggrant(log, ticket, + "xlog_regrant_reserve_log_space: enter"); + if (ticket->t_cnt > 0) + ticket->t_cnt--; + + s = GRANT_LOCK(log); + XLOG_GRANT_SUB_SPACE(log, ticket->t_curr_res, 'w'); + XLOG_GRANT_SUB_SPACE(log, ticket->t_curr_res, 'r'); + ticket->t_curr_res = ticket->t_unit_res; + xlog_trace_loggrant(log, ticket, + "xlog_regrant_reserve_log_space: sub current res"); + xlog_verify_grant_head(log, 1); + + /* just return if we still have some of the pre-reserved space */ + if (ticket->t_cnt > 0) { + GRANT_UNLOCK(log, s); + return; + } + + XLOG_GRANT_ADD_SPACE(log, ticket->t_unit_res, 'r'); + xlog_trace_loggrant(log, ticket, + "xlog_regrant_reserve_log_space: exit"); + xlog_verify_grant_head(log, 0); + GRANT_UNLOCK(log, s); + ticket->t_curr_res = ticket->t_unit_res; +} /* xlog_regrant_reserve_log_space */ + + +/* + * Give back the space left from a reservation. + * + * All the information we need to make a correct determination of space left + * is present. For non-permanent reservations, things are quite easy. The + * count should have been decremented to zero. We only need to deal with the + * space remaining in the current reservation part of the ticket. If the + * ticket contains a permanent reservation, there may be left over space which + * needs to be released. A count of N means that N-1 refills of the current + * reservation can be done before we need to ask for more space. The first + * one goes to fill up the first current reservation. Once we run out of + * space, the count will stay at zero and the only space remaining will be + * in the current reservation field. + */ +STATIC void +xlog_ungrant_log_space(xlog_t *log, + xlog_ticket_t *ticket) +{ + SPLDECL(s); + + if (ticket->t_cnt > 0) + ticket->t_cnt--; + + s = GRANT_LOCK(log); + xlog_trace_loggrant(log, ticket, "xlog_ungrant_log_space: enter"); + + XLOG_GRANT_SUB_SPACE(log, ticket->t_curr_res, 'w'); + XLOG_GRANT_SUB_SPACE(log, ticket->t_curr_res, 'r'); + + xlog_trace_loggrant(log, ticket, "xlog_ungrant_log_space: sub current"); + + /* If this is a permanent reservation ticket, we may be able to free + * up more space based on the remaining count. + */ + if (ticket->t_cnt > 0) { + ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV); + XLOG_GRANT_SUB_SPACE(log, ticket->t_unit_res*ticket->t_cnt,'w'); + XLOG_GRANT_SUB_SPACE(log, ticket->t_unit_res*ticket->t_cnt,'r'); + } + + xlog_trace_loggrant(log, ticket, "xlog_ungrant_log_space: exit"); + xlog_verify_grant_head(log, 1); + GRANT_UNLOCK(log, s); + xfs_log_move_tail(log->l_mp, 1); +} /* xlog_ungrant_log_space */ + + +/* + * Atomically put back used ticket. + */ +void +xlog_state_put_ticket(xlog_t *log, + xlog_ticket_t *tic) +{ + unsigned long s; + + s = LOG_LOCK(log); + xlog_ticket_put(log, tic); + LOG_UNLOCK(log, s); +} /* xlog_state_put_ticket */ + +/* + * Flush iclog to disk if this is the last reference to the given iclog and + * the WANT_SYNC bit is set. + * + * When this function is entered, the iclog is not necessarily in the + * WANT_SYNC state. It may be sitting around waiting to get filled. + * + * + */ +int +xlog_state_release_iclog(xlog_t *log, + xlog_in_core_t *iclog) +{ + SPLDECL(s); + int sync = 0; /* do we sync? */ + + xlog_assign_tail_lsn(log->l_mp); + + s = LOG_LOCK(log); + + if (iclog->ic_state & XLOG_STATE_IOERROR) { + LOG_UNLOCK(log, s); + return XFS_ERROR(EIO); + } + + ASSERT(iclog->ic_refcnt > 0); + ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE || + iclog->ic_state == XLOG_STATE_WANT_SYNC); + + if (--iclog->ic_refcnt == 0 && + iclog->ic_state == XLOG_STATE_WANT_SYNC) { + sync++; + iclog->ic_state = XLOG_STATE_SYNCING; + INT_SET(iclog->ic_header.h_tail_lsn, ARCH_CONVERT, log->l_tail_lsn); + xlog_verify_tail_lsn(log, iclog, log->l_tail_lsn); + /* cycle incremented when incrementing curr_block */ + } + + LOG_UNLOCK(log, s); + + /* + * We let the log lock go, so it's possible that we hit a log I/O + * error or someother SHUTDOWN condition that marks the iclog + * as XLOG_STATE_IOERROR before the bwrite. However, we know that + * this iclog has consistent data, so we ignore IOERROR + * flags after this point. + */ + if (sync) { + return xlog_sync(log, iclog); + } + return (0); + +} /* xlog_state_release_iclog */ + + +/* + * This routine will mark the current iclog in the ring as WANT_SYNC + * and move the current iclog pointer to the next iclog in the ring. + * When this routine is called from xlog_state_get_iclog_space(), the + * exact size of the iclog has not yet been determined. All we know is + * that every data block. We have run out of space in this log record. + */ +STATIC void +xlog_state_switch_iclogs(xlog_t *log, + xlog_in_core_t *iclog, + int eventual_size) +{ + ASSERT(iclog->ic_state == XLOG_STATE_ACTIVE); + if (!eventual_size) + eventual_size = iclog->ic_offset; + iclog->ic_state = XLOG_STATE_WANT_SYNC; + INT_SET(iclog->ic_header.h_prev_block, ARCH_CONVERT, log->l_prev_block); + log->l_prev_block = log->l_curr_block; + log->l_prev_cycle = log->l_curr_cycle; + + /* roll log?: ic_offset changed later */ + log->l_curr_block += BTOBB(eventual_size)+BTOBB(log->l_iclog_hsize); + + /* Round up to next log-sunit */ + if (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) && + log->l_mp->m_sb.sb_logsunit > 1) { + __uint32_t sunit_bb = BTOBB(log->l_mp->m_sb.sb_logsunit); + log->l_curr_block = roundup(log->l_curr_block, sunit_bb); + } + + if (log->l_curr_block >= log->l_logBBsize) { + log->l_curr_cycle++; + if (log->l_curr_cycle == XLOG_HEADER_MAGIC_NUM) + log->l_curr_cycle++; + log->l_curr_block -= log->l_logBBsize; + ASSERT(log->l_curr_block >= 0); + } + ASSERT(iclog == log->l_iclog); + log->l_iclog = iclog->ic_next; +} /* xlog_state_switch_iclogs */ + + +/* + * Write out all data in the in-core log as of this exact moment in time. + * + * Data may be written to the in-core log during this call. However, + * we don't guarantee this data will be written out. A change from past + * implementation means this routine will *not* write out zero length LRs. + * + * Basically, we try and perform an intelligent scan of the in-core logs. + * If we determine there is no flushable data, we just return. There is no + * flushable data if: + * + * 1. the current iclog is active and has no data; the previous iclog + * is in the active or dirty state. + * 2. the current iclog is drity, and the previous iclog is in the + * active or dirty state. + * + * We may sleep (call psema) if: + * + * 1. the current iclog is not in the active nor dirty state. + * 2. the current iclog dirty, and the previous iclog is not in the + * active nor dirty state. + * 3. the current iclog is active, and there is another thread writing + * to this particular iclog. + * 4. a) the current iclog is active and has no other writers + * b) when we return from flushing out this iclog, it is still + * not in the active nor dirty state. + */ +STATIC int +xlog_state_sync_all(xlog_t *log, uint flags) +{ + xlog_in_core_t *iclog; + xfs_lsn_t lsn; + SPLDECL(s); + + s = LOG_LOCK(log); + + iclog = log->l_iclog; + if (iclog->ic_state & XLOG_STATE_IOERROR) { + LOG_UNLOCK(log, s); + return XFS_ERROR(EIO); + } + + /* If the head iclog is not active nor dirty, we just attach + * ourselves to the head and go to sleep. + */ + if (iclog->ic_state == XLOG_STATE_ACTIVE || + iclog->ic_state == XLOG_STATE_DIRTY) { + /* + * If the head is dirty or (active and empty), then + * we need to look at the previous iclog. If the previous + * iclog is active or dirty we are done. There is nothing + * to sync out. Otherwise, we attach ourselves to the + * previous iclog and go to sleep. + */ + if (iclog->ic_state == XLOG_STATE_DIRTY || + (iclog->ic_refcnt == 0 && iclog->ic_offset == 0)) { + iclog = iclog->ic_prev; + if (iclog->ic_state == XLOG_STATE_ACTIVE || + iclog->ic_state == XLOG_STATE_DIRTY) + goto no_sleep; + else + goto maybe_sleep; + } else { + if (iclog->ic_refcnt == 0) { + /* We are the only one with access to this + * iclog. Flush it out now. There should + * be a roundoff of zero to show that someone + * has already taken care of the roundoff from + * the previous sync. + */ + iclog->ic_refcnt++; + lsn = INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT); + xlog_state_switch_iclogs(log, iclog, 0); + LOG_UNLOCK(log, s); + + if (xlog_state_release_iclog(log, iclog)) + return XFS_ERROR(EIO); + s = LOG_LOCK(log); + if (INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT) == lsn && + iclog->ic_state != XLOG_STATE_DIRTY) + goto maybe_sleep; + else + goto no_sleep; + } else { + /* Someone else is writing to this iclog. + * Use its call to flush out the data. However, + * the other thread may not force out this LR, + * so we mark it WANT_SYNC. + */ + xlog_state_switch_iclogs(log, iclog, 0); + goto maybe_sleep; + } + } + } + + /* By the time we come around again, the iclog could've been filled + * which would give it another lsn. If we have a new lsn, just + * return because the relevant data has been flushed. + */ +maybe_sleep: + if (flags & XFS_LOG_SYNC) { + /* + * We must check if we're shutting down here, before + * we wait, while we're holding the LOG_LOCK. + * Then we check again after waking up, in case our + * sleep was disturbed by a bad news. + */ + if (iclog->ic_state & XLOG_STATE_IOERROR) { + LOG_UNLOCK(log, s); + return XFS_ERROR(EIO); + } + XFS_STATS_INC(xs_log_force_sleep); + sv_wait(&iclog->ic_forcesema, PINOD, &log->l_icloglock, s); + /* + * No need to grab the log lock here since we're + * only deciding whether or not to return EIO + * and the memory read should be atomic. + */ + if (iclog->ic_state & XLOG_STATE_IOERROR) + return XFS_ERROR(EIO); + + } else { + +no_sleep: + LOG_UNLOCK(log, s); + } + return 0; +} /* xlog_state_sync_all */ + + +/* + * Used by code which implements synchronous log forces. + * + * Find in-core log with lsn. + * If it is in the DIRTY state, just return. + * If it is in the ACTIVE state, move the in-core log into the WANT_SYNC + * state and go to sleep or return. + * If it is in any other state, go to sleep or return. + * + * If filesystem activity goes to zero, the iclog will get flushed only by + * bdflush(). + */ +int +xlog_state_sync(xlog_t *log, + xfs_lsn_t lsn, + uint flags) +{ + xlog_in_core_t *iclog; + int already_slept = 0; + SPLDECL(s); + + +try_again: + s = LOG_LOCK(log); + iclog = log->l_iclog; + + if (iclog->ic_state & XLOG_STATE_IOERROR) { + LOG_UNLOCK(log, s); + return XFS_ERROR(EIO); + } + + do { + if (INT_GET(iclog->ic_header.h_lsn, ARCH_CONVERT) != lsn) { + iclog = iclog->ic_next; + continue; + } + + if (iclog->ic_state == XLOG_STATE_DIRTY) { + LOG_UNLOCK(log, s); + return 0; + } + + if (iclog->ic_state == XLOG_STATE_ACTIVE) { + /* + * We sleep here if we haven't already slept (e.g. + * this is the first time we've looked at the correct + * iclog buf) and the buffer before us is going to + * be sync'ed. The reason for this is that if we + * are doing sync transactions here, by waiting for + * the previous I/O to complete, we can allow a few + * more transactions into this iclog before we close + * it down. + * + * Otherwise, we mark the buffer WANT_SYNC, and bump + * up the refcnt so we can release the log (which drops + * the ref count). The state switch keeps new transaction + * commits from using this buffer. When the current commits + * finish writing into the buffer, the refcount will drop to + * zero and the buffer will go out then. + */ + if (!already_slept && + (iclog->ic_prev->ic_state & (XLOG_STATE_WANT_SYNC | + XLOG_STATE_SYNCING))) { + ASSERT(!(iclog->ic_state & XLOG_STATE_IOERROR)); + XFS_STATS_INC(xs_log_force_sleep); + sv_wait(&iclog->ic_prev->ic_writesema, PSWP, + &log->l_icloglock, s); + already_slept = 1; + goto try_again; + } else { + iclog->ic_refcnt++; + xlog_state_switch_iclogs(log, iclog, 0); + LOG_UNLOCK(log, s); + if (xlog_state_release_iclog(log, iclog)) + return XFS_ERROR(EIO); + s = LOG_LOCK(log); + } + } + + if ((flags & XFS_LOG_SYNC) && /* sleep */ + !(iclog->ic_state & (XLOG_STATE_ACTIVE | XLOG_STATE_DIRTY))) { + + /* + * Don't wait on the forcesema if we know that we've + * gotten a log write error. + */ + if (iclog->ic_state & XLOG_STATE_IOERROR) { + LOG_UNLOCK(log, s); + return XFS_ERROR(EIO); + } + XFS_STATS_INC(xs_log_force_sleep); + sv_wait(&iclog->ic_forcesema, PSWP, &log->l_icloglock, s); + /* + * No need to grab the log lock here since we're + * only deciding whether or not to return EIO + * and the memory read should be atomic. + */ + if (iclog->ic_state & XLOG_STATE_IOERROR) + return XFS_ERROR(EIO); + } else { /* just return */ + LOG_UNLOCK(log, s); + } + return 0; + + } while (iclog != log->l_iclog); + + LOG_UNLOCK(log, s); + return (0); +} /* xlog_state_sync */ + + +/* + * Called when we want to mark the current iclog as being ready to sync to + * disk. + */ +void +xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog) +{ + SPLDECL(s); + + s = LOG_LOCK(log); + + if (iclog->ic_state == XLOG_STATE_ACTIVE) { + xlog_state_switch_iclogs(log, iclog, 0); + } else { + ASSERT(iclog->ic_state & + (XLOG_STATE_WANT_SYNC|XLOG_STATE_IOERROR)); + } + + LOG_UNLOCK(log, s); +} /* xlog_state_want_sync */ + + + +/***************************************************************************** + * + * TICKET functions + * + ***************************************************************************** + */ + +/* + * Algorithm doesn't take into account page size. ;-( + */ +STATIC void +xlog_state_ticket_alloc(xlog_t *log) +{ + xlog_ticket_t *t_list; + xlog_ticket_t *next; + xfs_caddr_t buf; + uint i = (NBPP / sizeof(xlog_ticket_t)) - 2; + SPLDECL(s); + + /* + * The kmem_zalloc may sleep, so we shouldn't be holding the + * global lock. XXXmiken: may want to use zone allocator. + */ + buf = (xfs_caddr_t) kmem_zalloc(NBPP, KM_SLEEP); + + s = LOG_LOCK(log); + + /* Attach 1st ticket to Q, so we can keep track of allocated memory */ + t_list = (xlog_ticket_t *)buf; + t_list->t_next = log->l_unmount_free; + log->l_unmount_free = t_list++; + log->l_ticket_cnt++; + log->l_ticket_tcnt++; + + /* Next ticket becomes first ticket attached to ticket free list */ + if (log->l_freelist != NULL) { + ASSERT(log->l_tail != NULL); + log->l_tail->t_next = t_list; + } else { + log->l_freelist = t_list; + } + log->l_ticket_cnt++; + log->l_ticket_tcnt++; + + /* Cycle through rest of alloc'ed memory, building up free Q */ + for ( ; i > 0; i--) { + next = t_list + 1; + t_list->t_next = next; + t_list = next; + log->l_ticket_cnt++; + log->l_ticket_tcnt++; + } + t_list->t_next = NULL; + log->l_tail = t_list; + LOG_UNLOCK(log, s); +} /* xlog_state_ticket_alloc */ + + +/* + * Put ticket into free list + * + * Assumption: log lock is held around this call. + */ +STATIC void +xlog_ticket_put(xlog_t *log, + xlog_ticket_t *ticket) +{ + sv_destroy(&ticket->t_sema); + + /* + * Don't think caching will make that much difference. It's + * more important to make debug easier. + */ +#if 0 + /* real code will want to use LIFO for caching */ + ticket->t_next = log->l_freelist; + log->l_freelist = ticket; + /* no need to clear fields */ +#else + /* When we debug, it is easier if tickets are cycled */ + ticket->t_next = NULL; + if (log->l_tail != 0) { + log->l_tail->t_next = ticket; + } else { + ASSERT(log->l_freelist == 0); + log->l_freelist = ticket; + } + log->l_tail = ticket; +#endif /* DEBUG */ + log->l_ticket_cnt++; +} /* xlog_ticket_put */ + + +/* + * Grab ticket off freelist or allocation some more + */ +xlog_ticket_t * +xlog_ticket_get(xlog_t *log, + int unit_bytes, + int cnt, + char client, + uint xflags) +{ + xlog_ticket_t *tic; + uint num_headers; + SPLDECL(s); + + alloc: + if (log->l_freelist == NULL) + xlog_state_ticket_alloc(log); /* potentially sleep */ + + s = LOG_LOCK(log); + if (log->l_freelist == NULL) { + LOG_UNLOCK(log, s); + goto alloc; + } + tic = log->l_freelist; + log->l_freelist = tic->t_next; + if (log->l_freelist == NULL) + log->l_tail = NULL; + log->l_ticket_cnt--; + LOG_UNLOCK(log, s); + + /* + * Permanent reservations have up to 'cnt'-1 active log operations + * in the log. A unit in this case is the amount of space for one + * of these log operations. Normal reservations have a cnt of 1 + * and their unit amount is the total amount of space required. + * + * The following lines of code account for non-transaction data + * which occupy space in the on-disk log. + */ + + /* for start-rec */ + unit_bytes += sizeof(xlog_op_header_t); + + /* for padding */ + if (XFS_SB_VERSION_HASLOGV2(&log->l_mp->m_sb) && + log->l_mp->m_sb.sb_logsunit > 1) { + /* log su roundoff */ + unit_bytes += log->l_mp->m_sb.sb_logsunit; + } else { + /* BB roundoff */ + unit_bytes += BBSIZE; + } + + /* for commit-rec */ + unit_bytes += sizeof(xlog_op_header_t); + + /* for LR headers */ + num_headers = ((unit_bytes + log->l_iclog_size-1) >> log->l_iclog_size_log); + unit_bytes += log->l_iclog_hsize * num_headers; + + tic->t_unit_res = unit_bytes; + tic->t_curr_res = unit_bytes; + tic->t_cnt = cnt; + tic->t_ocnt = cnt; + tic->t_tid = (xlog_tid_t)((__psint_t)tic & 0xffffffff); + tic->t_clientid = client; + tic->t_flags = XLOG_TIC_INITED; + if (xflags & XFS_LOG_PERM_RESERV) + tic->t_flags |= XLOG_TIC_PERM_RESERV; + sv_init(&(tic->t_sema), SV_DEFAULT, "logtick"); + + return tic; +} /* xlog_ticket_get */ + + +/****************************************************************************** + * + * Log debug routines + * + ****************************************************************************** + */ +#if defined(DEBUG) && !defined(XLOG_NOLOG) +/* + * Make sure that the destination ptr is within the valid data region of + * one of the iclogs. This uses backup pointers stored in a different + * part of the log in case we trash the log structure. + */ +void +xlog_verify_dest_ptr(xlog_t *log, + __psint_t ptr) +{ + int i; + int good_ptr = 0; + + for (i=0; i < log->l_iclog_bufs; i++) { + if (ptr >= (__psint_t)log->l_iclog_bak[i] && + ptr <= (__psint_t)log->l_iclog_bak[i]+log->l_iclog_size) + good_ptr++; + } + if (! good_ptr) + xlog_panic("xlog_verify_dest_ptr: invalid ptr"); +} /* xlog_verify_dest_ptr */ + +STATIC void +xlog_verify_grant_head(xlog_t *log, int equals) +{ + if (log->l_grant_reserve_cycle == log->l_grant_write_cycle) { + if (equals) + ASSERT(log->l_grant_reserve_bytes >= log->l_grant_write_bytes); + else + ASSERT(log->l_grant_reserve_bytes > log->l_grant_write_bytes); + } else { + ASSERT(log->l_grant_reserve_cycle-1 == log->l_grant_write_cycle); + ASSERT(log->l_grant_write_bytes >= log->l_grant_reserve_bytes); + } +} /* xlog_verify_grant_head */ + +/* check if it will fit */ +STATIC void +xlog_verify_tail_lsn(xlog_t *log, + xlog_in_core_t *iclog, + xfs_lsn_t tail_lsn) +{ + int blocks; + + if (CYCLE_LSN(tail_lsn) == log->l_prev_cycle) { + blocks = + log->l_logBBsize - (log->l_prev_block - BLOCK_LSN(tail_lsn)); + if (blocks < BTOBB(iclog->ic_offset)+BTOBB(log->l_iclog_hsize)) + xlog_panic("xlog_verify_tail_lsn: ran out of log space"); + } else { + ASSERT(CYCLE_LSN(tail_lsn)+1 == log->l_prev_cycle); + + if (BLOCK_LSN(tail_lsn) == log->l_prev_block) + xlog_panic("xlog_verify_tail_lsn: tail wrapped"); + + blocks = BLOCK_LSN(tail_lsn) - log->l_prev_block; + if (blocks < BTOBB(iclog->ic_offset) + 1) + xlog_panic("xlog_verify_tail_lsn: ran out of log space"); + } +} /* xlog_verify_tail_lsn */ + +/* + * Perform a number of checks on the iclog before writing to disk. + * + * 1. Make sure the iclogs are still circular + * 2. Make sure we have a good magic number + * 3. Make sure we don't have magic numbers in the data + * 4. Check fields of each log operation header for: + * A. Valid client identifier + * B. tid ptr value falls in valid ptr space (user space code) + * C. Length in log record header is correct according to the + * individual operation headers within record. + * 5. When a bwrite will occur within 5 blocks of the front of the physical + * log, check the preceding blocks of the physical log to make sure all + * the cycle numbers agree with the current cycle number. + */ +STATIC void +xlog_verify_iclog(xlog_t *log, + xlog_in_core_t *iclog, + int count, + boolean_t syncing) +{ + xlog_op_header_t *ophead; + xlog_in_core_t *icptr; + xlog_in_core_2_t *xhdr; + xfs_caddr_t ptr; + xfs_caddr_t base_ptr; + __psint_t field_offset; + __uint8_t clientid; + int len, i, j, k, op_len; + int idx; + SPLDECL(s); + + /* check validity of iclog pointers */ + s = LOG_LOCK(log); + icptr = log->l_iclog; + for (i=0; i < log->l_iclog_bufs; i++) { + if (icptr == 0) + xlog_panic("xlog_verify_iclog: invalid ptr"); + icptr = icptr->ic_next; + } + if (icptr != log->l_iclog) + xlog_panic("xlog_verify_iclog: corrupt iclog ring"); + LOG_UNLOCK(log, s); + + /* check log magic numbers */ + ptr = (xfs_caddr_t) &(iclog->ic_header); + if (INT_GET(*(uint *)ptr, ARCH_CONVERT) != XLOG_HEADER_MAGIC_NUM) + xlog_panic("xlog_verify_iclog: invalid magic num"); + + for (ptr += BBSIZE; ptr < ((xfs_caddr_t)&(iclog->ic_header))+count; + ptr += BBSIZE) { + if (INT_GET(*(uint *)ptr, ARCH_CONVERT) == XLOG_HEADER_MAGIC_NUM) + xlog_panic("xlog_verify_iclog: unexpected magic num"); + } + + /* check fields */ + len = INT_GET(iclog->ic_header.h_num_logops, ARCH_CONVERT); + ptr = iclog->ic_datap; + base_ptr = ptr; + ophead = (xlog_op_header_t *)ptr; + xhdr = (xlog_in_core_2_t *)&iclog->ic_header; + for (i = 0; i < len; i++) { + ophead = (xlog_op_header_t *)ptr; + + /* clientid is only 1 byte */ + field_offset = (__psint_t) + ((xfs_caddr_t)&(ophead->oh_clientid) - base_ptr); + if (syncing == B_FALSE || (field_offset & 0x1ff)) { + clientid = ophead->oh_clientid; + } else { + idx = BTOBBT((xfs_caddr_t)&(ophead->oh_clientid) - iclog->ic_datap); + if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { + j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); + k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); + clientid = GET_CLIENT_ID(xhdr[j].hic_xheader.xh_cycle_data[k], ARCH_CONVERT); + } else { + clientid = GET_CLIENT_ID(iclog->ic_header.h_cycle_data[idx], ARCH_CONVERT); + } + } + if (clientid != XFS_TRANSACTION && clientid != XFS_LOG) + cmn_err(CE_WARN, "xlog_verify_iclog: invalid clientid %d op 0x%p offset 0x%x", clientid, ophead, field_offset); + + /* check length */ + field_offset = (__psint_t) + ((xfs_caddr_t)&(ophead->oh_len) - base_ptr); + if (syncing == B_FALSE || (field_offset & 0x1ff)) { + op_len = INT_GET(ophead->oh_len, ARCH_CONVERT); + } else { + idx = BTOBBT((__psint_t)&ophead->oh_len - + (__psint_t)iclog->ic_datap); + if (idx >= (XLOG_HEADER_CYCLE_SIZE / BBSIZE)) { + j = idx / (XLOG_HEADER_CYCLE_SIZE / BBSIZE); + k = idx % (XLOG_HEADER_CYCLE_SIZE / BBSIZE); + op_len = INT_GET(xhdr[j].hic_xheader.xh_cycle_data[k], ARCH_CONVERT); + } else { + op_len = INT_GET(iclog->ic_header.h_cycle_data[idx], ARCH_CONVERT); + } + } + ptr += sizeof(xlog_op_header_t) + op_len; + } +} /* xlog_verify_iclog */ +#endif /* DEBUG && !XLOG_NOLOG */ + +/* + * Mark all iclogs IOERROR. LOG_LOCK is held by the caller. + */ +STATIC int +xlog_state_ioerror( + xlog_t *log) +{ + xlog_in_core_t *iclog, *ic; + + iclog = log->l_iclog; + if (! (iclog->ic_state & XLOG_STATE_IOERROR)) { + /* + * Mark all the incore logs IOERROR. + * From now on, no log flushes will result. + */ + ic = iclog; + do { + ic->ic_state = XLOG_STATE_IOERROR; + ic = ic->ic_next; + } while (ic != iclog); + return (0); + } + /* + * Return non-zero, if state transition has already happened. + */ + return (1); +} + +/* + * This is called from xfs_force_shutdown, when we're forcibly + * shutting down the filesystem, typically because of an IO error. + * Our main objectives here are to make sure that: + * a. the filesystem gets marked 'SHUTDOWN' for all interested + * parties to find out, 'atomically'. + * b. those who're sleeping on log reservations, pinned objects and + * other resources get woken up, and be told the bad news. + * c. nothing new gets queued up after (a) and (b) are done. + * d. if !logerror, flush the iclogs to disk, then seal them off + * for business. + */ +int +xfs_log_force_umount( + struct xfs_mount *mp, + int logerror) +{ + xlog_ticket_t *tic; + xlog_t *log; + int retval; + SPLDECL(s); + SPLDECL(s2); + + log = mp->m_log; + + /* + * If this happens during log recovery, don't worry about + * locking; the log isn't open for business yet. + */ + if (!log || + log->l_flags & XLOG_ACTIVE_RECOVERY) { + mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; + XFS_BUF_DONE(mp->m_sb_bp); + return (0); + } + + /* + * Somebody could've already done the hard work for us. + * No need to get locks for this. + */ + if (logerror && log->l_iclog->ic_state & XLOG_STATE_IOERROR) { + ASSERT(XLOG_FORCED_SHUTDOWN(log)); + return (1); + } + retval = 0; + /* + * We must hold both the GRANT lock and the LOG lock, + * before we mark the filesystem SHUTDOWN and wake + * everybody up to tell the bad news. + */ + s = GRANT_LOCK(log); + s2 = LOG_LOCK(log); + mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; + XFS_BUF_DONE(mp->m_sb_bp); + /* + * This flag is sort of redundant because of the mount flag, but + * it's good to maintain the separation between the log and the rest + * of XFS. + */ + log->l_flags |= XLOG_IO_ERROR; + + /* + * If we hit a log error, we want to mark all the iclogs IOERROR + * while we're still holding the loglock. + */ + if (logerror) + retval = xlog_state_ioerror(log); + LOG_UNLOCK(log, s2); + + /* + * We don't want anybody waiting for log reservations + * after this. That means we have to wake up everybody + * queued up on reserve_headq as well as write_headq. + * In addition, we make sure in xlog_{re}grant_log_space + * that we don't enqueue anything once the SHUTDOWN flag + * is set, and this action is protected by the GRANTLOCK. + */ + if ((tic = log->l_reserve_headq)) { + do { + sv_signal(&tic->t_sema); + tic = tic->t_next; + } while (tic != log->l_reserve_headq); + } + + if ((tic = log->l_write_headq)) { + do { + sv_signal(&tic->t_sema); + tic = tic->t_next; + } while (tic != log->l_write_headq); + } + GRANT_UNLOCK(log, s); + + if (! (log->l_iclog->ic_state & XLOG_STATE_IOERROR)) { + ASSERT(!logerror); + /* + * Force the incore logs to disk before shutting the + * log down completely. + */ + xlog_state_sync_all(log, XFS_LOG_FORCE|XFS_LOG_SYNC); + s2 = LOG_LOCK(log); + retval = xlog_state_ioerror(log); + LOG_UNLOCK(log, s2); + } + /* + * Wake up everybody waiting on xfs_log_force. + * Callback all log item committed functions as if the + * log writes were completed. + */ + xlog_state_do_callback(log, XFS_LI_ABORTED, NULL); + +#ifdef XFSERRORDEBUG + { + xlog_in_core_t *iclog; + + s = LOG_LOCK(log); + iclog = log->l_iclog; + do { + ASSERT(iclog->ic_callback == 0); + iclog = iclog->ic_next; + } while (iclog != log->l_iclog); + LOG_UNLOCK(log, s); + } +#endif + /* return non-zero if log IOERROR transition had already happened */ + return (retval); +} + +int +xlog_iclogs_empty(xlog_t *log) +{ + xlog_in_core_t *iclog; + + iclog = log->l_iclog; + do { + /* endianness does not matter here, zero is zero in + * any language. + */ + if (iclog->ic_header.h_num_logops) + return(0); + iclog = iclog->ic_next; + } while (iclog != log->l_iclog); + return(1); +} |