diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-15 10:38:46 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-15 10:38:46 -0700 |
commit | 38c46578ffd8ffbfec514c2a9876d527303322d6 (patch) | |
tree | d55ad8a52048f70bc6ef51d388c0f21ff467155e /fs/gfs2/locking/dlm/lock.c | |
parent | e7849f16c13476288fe4fbd420975e8456c75aa0 (diff) | |
parent | 4abaca17e758e3326c96ced88b2cd9b7b84922f6 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw:
[GFS2] Fix GFS2's use of do_div() in its quota calculations
[GFS2] Remove unused declaration
[GFS2] Remove support for unused and pointless flag
[GFS2] Replace rgrp "recent list" with mru list
[GFS2] Allow local DF locks when holding a cached EX glock
[GFS2] Fix delayed demote race
[GFS2] don't call permission()
[GFS2] Fix module building
[GFS2] Glock documentation
[GFS2] Remove all_list from lock_dlm
[GFS2] Remove obsolete conversion deadlock avoidance code
[GFS2] Remove remote lock dropping code
[GFS2] kernel panic mounting volume
[GFS2] Revise readpage locking
[GFS2] Fix ordering of args for list_add
[GFS2] trivial sparse lock annotations
[GFS2] No lock_nolock
[GFS2] Fix ordering bug in lock_dlm
[GFS2] Clean up the glock core
Diffstat (limited to 'fs/gfs2/locking/dlm/lock.c')
-rw-r--r-- | fs/gfs2/locking/dlm/lock.c | 368 |
1 files changed, 274 insertions, 94 deletions
diff --git a/fs/gfs2/locking/dlm/lock.c b/fs/gfs2/locking/dlm/lock.c index cf7ea8abec8..2482c904750 100644 --- a/fs/gfs2/locking/dlm/lock.c +++ b/fs/gfs2/locking/dlm/lock.c @@ -11,46 +11,60 @@ static char junk_lvb[GDLM_LVB_SIZE]; -static void queue_complete(struct gdlm_lock *lp) + +/* convert dlm lock-mode to gfs lock-state */ + +static s16 gdlm_make_lmstate(s16 dlmmode) { - struct gdlm_ls *ls = lp->ls; + switch (dlmmode) { + case DLM_LOCK_IV: + case DLM_LOCK_NL: + return LM_ST_UNLOCKED; + case DLM_LOCK_EX: + return LM_ST_EXCLUSIVE; + case DLM_LOCK_CW: + return LM_ST_DEFERRED; + case DLM_LOCK_PR: + return LM_ST_SHARED; + } + gdlm_assert(0, "unknown DLM mode %d", dlmmode); + return -1; +} - clear_bit(LFL_ACTIVE, &lp->flags); +/* A lock placed on this queue is re-submitted to DLM as soon as the lock_dlm + thread gets to it. */ + +static void queue_submit(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; spin_lock(&ls->async_lock); - list_add_tail(&lp->clist, &ls->complete); + list_add_tail(&lp->delay_list, &ls->submit); spin_unlock(&ls->async_lock); wake_up(&ls->thread_wait); } -static inline void gdlm_ast(void *astarg) +static void wake_up_ast(struct gdlm_lock *lp) { - queue_complete(astarg); + clear_bit(LFL_AST_WAIT, &lp->flags); + smp_mb__after_clear_bit(); + wake_up_bit(&lp->flags, LFL_AST_WAIT); } -static inline void gdlm_bast(void *astarg, int mode) +static void gdlm_delete_lp(struct gdlm_lock *lp) { - struct gdlm_lock *lp = astarg; struct gdlm_ls *ls = lp->ls; - if (!mode) { - printk(KERN_INFO "lock_dlm: bast mode zero %x,%llx\n", - lp->lockname.ln_type, - (unsigned long long)lp->lockname.ln_number); - return; - } - spin_lock(&ls->async_lock); - if (!lp->bast_mode) { - list_add_tail(&lp->blist, &ls->blocking); - lp->bast_mode = mode; - } else if (lp->bast_mode < mode) - lp->bast_mode = mode; + if (!list_empty(&lp->delay_list)) + list_del_init(&lp->delay_list); + ls->all_locks_count--; spin_unlock(&ls->async_lock); - wake_up(&ls->thread_wait); + + kfree(lp); } -void gdlm_queue_delayed(struct gdlm_lock *lp) +static void gdlm_queue_delayed(struct gdlm_lock *lp) { struct gdlm_ls *ls = lp->ls; @@ -59,6 +73,236 @@ void gdlm_queue_delayed(struct gdlm_lock *lp) spin_unlock(&ls->async_lock); } +static void process_complete(struct gdlm_lock *lp) +{ + struct gdlm_ls *ls = lp->ls; + struct lm_async_cb acb; + + memset(&acb, 0, sizeof(acb)); + + if (lp->lksb.sb_status == -DLM_ECANCEL) { + log_info("complete dlm cancel %x,%llx flags %lx", + lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number, + lp->flags); + + lp->req = lp->cur; + acb.lc_ret |= LM_OUT_CANCELED; + if (lp->cur == DLM_LOCK_IV) + lp->lksb.sb_lkid = 0; + goto out; + } + + if (test_and_clear_bit(LFL_DLM_UNLOCK, &lp->flags)) { + if (lp->lksb.sb_status != -DLM_EUNLOCK) { + log_info("unlock sb_status %d %x,%llx flags %lx", + lp->lksb.sb_status, lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number, + lp->flags); + return; + } + + lp->cur = DLM_LOCK_IV; + lp->req = DLM_LOCK_IV; + lp->lksb.sb_lkid = 0; + + if (test_and_clear_bit(LFL_UNLOCK_DELETE, &lp->flags)) { + gdlm_delete_lp(lp); + return; + } + goto out; + } + + if (lp->lksb.sb_flags & DLM_SBF_VALNOTVALID) + memset(lp->lksb.sb_lvbptr, 0, GDLM_LVB_SIZE); + + if (lp->lksb.sb_flags & DLM_SBF_ALTMODE) { + if (lp->req == DLM_LOCK_PR) + lp->req = DLM_LOCK_CW; + else if (lp->req == DLM_LOCK_CW) + lp->req = DLM_LOCK_PR; + } + + /* + * A canceled lock request. The lock was just taken off the delayed + * list and was never even submitted to dlm. + */ + + if (test_and_clear_bit(LFL_CANCEL, &lp->flags)) { + log_info("complete internal cancel %x,%llx", + lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number); + lp->req = lp->cur; + acb.lc_ret |= LM_OUT_CANCELED; + goto out; + } + + /* + * An error occured. + */ + + if (lp->lksb.sb_status) { + /* a "normal" error */ + if ((lp->lksb.sb_status == -EAGAIN) && + (lp->lkf & DLM_LKF_NOQUEUE)) { + lp->req = lp->cur; + if (lp->cur == DLM_LOCK_IV) + lp->lksb.sb_lkid = 0; + goto out; + } + + /* this could only happen with cancels I think */ + log_info("ast sb_status %d %x,%llx flags %lx", + lp->lksb.sb_status, lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number, + lp->flags); + return; + } + + /* + * This is an AST for an EX->EX conversion for sync_lvb from GFS. + */ + + if (test_and_clear_bit(LFL_SYNC_LVB, &lp->flags)) { + wake_up_ast(lp); + return; + } + + /* + * A lock has been demoted to NL because it initially completed during + * BLOCK_LOCKS. Now it must be requested in the originally requested + * mode. + */ + + if (test_and_clear_bit(LFL_REREQUEST, &lp->flags)) { + gdlm_assert(lp->req == DLM_LOCK_NL, "%x,%llx", + lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number); + gdlm_assert(lp->prev_req > DLM_LOCK_NL, "%x,%llx", + lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number); + + lp->cur = DLM_LOCK_NL; + lp->req = lp->prev_req; + lp->prev_req = DLM_LOCK_IV; + lp->lkf &= ~DLM_LKF_CONVDEADLK; + + set_bit(LFL_NOCACHE, &lp->flags); + + if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) && + !test_bit(LFL_NOBLOCK, &lp->flags)) + gdlm_queue_delayed(lp); + else + queue_submit(lp); + return; + } + + /* + * A request is granted during dlm recovery. It may be granted + * because the locks of a failed node were cleared. In that case, + * there may be inconsistent data beneath this lock and we must wait + * for recovery to complete to use it. When gfs recovery is done this + * granted lock will be converted to NL and then reacquired in this + * granted state. + */ + + if (test_bit(DFL_BLOCK_LOCKS, &ls->flags) && + !test_bit(LFL_NOBLOCK, &lp->flags) && + lp->req != DLM_LOCK_NL) { + + lp->cur = lp->req; + lp->prev_req = lp->req; + lp->req = DLM_LOCK_NL; + lp->lkf |= DLM_LKF_CONVERT; + lp->lkf &= ~DLM_LKF_CONVDEADLK; + + log_debug("rereq %x,%llx id %x %d,%d", + lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number, + lp->lksb.sb_lkid, lp->cur, lp->req); + + set_bit(LFL_REREQUEST, &lp->flags); + queue_submit(lp); + return; + } + + /* + * DLM demoted the lock to NL before it was granted so GFS must be + * told it cannot cache data for this lock. + */ + + if (lp->lksb.sb_flags & DLM_SBF_DEMOTED) + set_bit(LFL_NOCACHE, &lp->flags); + +out: + /* + * This is an internal lock_dlm lock + */ + + if (test_bit(LFL_INLOCK, &lp->flags)) { + clear_bit(LFL_NOBLOCK, &lp->flags); + lp->cur = lp->req; + wake_up_ast(lp); + return; + } + + /* + * Normal completion of a lock request. Tell GFS it now has the lock. + */ + + clear_bit(LFL_NOBLOCK, &lp->flags); + lp->cur = lp->req; + + acb.lc_name = lp->lockname; + acb.lc_ret |= gdlm_make_lmstate(lp->cur); + + ls->fscb(ls->sdp, LM_CB_ASYNC, &acb); +} + +static void gdlm_ast(void *astarg) +{ + struct gdlm_lock *lp = astarg; + clear_bit(LFL_ACTIVE, &lp->flags); + process_complete(lp); +} + +static void process_blocking(struct gdlm_lock *lp, int bast_mode) +{ + struct gdlm_ls *ls = lp->ls; + unsigned int cb = 0; + + switch (gdlm_make_lmstate(bast_mode)) { + case LM_ST_EXCLUSIVE: + cb = LM_CB_NEED_E; + break; + case LM_ST_DEFERRED: + cb = LM_CB_NEED_D; + break; + case LM_ST_SHARED: + cb = LM_CB_NEED_S; + break; + default: + gdlm_assert(0, "unknown bast mode %u", bast_mode); + } + + ls->fscb(ls->sdp, cb, &lp->lockname); +} + + +static void gdlm_bast(void *astarg, int mode) +{ + struct gdlm_lock *lp = astarg; + + if (!mode) { + printk(KERN_INFO "lock_dlm: bast mode zero %x,%llx\n", + lp->lockname.ln_type, + (unsigned long long)lp->lockname.ln_number); + return; + } + + process_blocking(lp, mode); +} + /* convert gfs lock-state to dlm lock-mode */ static s16 make_mode(s16 lmstate) @@ -77,24 +321,6 @@ static s16 make_mode(s16 lmstate) return -1; } -/* convert dlm lock-mode to gfs lock-state */ - -s16 gdlm_make_lmstate(s16 dlmmode) -{ - switch (dlmmode) { - case DLM_LOCK_IV: - case DLM_LOCK_NL: - return LM_ST_UNLOCKED; - case DLM_LOCK_EX: - return LM_ST_EXCLUSIVE; - case DLM_LOCK_CW: - return LM_ST_DEFERRED; - case DLM_LOCK_PR: - return LM_ST_SHARED; - } - gdlm_assert(0, "unknown DLM mode %d", dlmmode); - return -1; -} /* verify agreement with GFS on the current lock state, NB: DLM_LOCK_NL and DLM_LOCK_IV are both considered LM_ST_UNLOCKED by GFS. */ @@ -134,14 +360,6 @@ static inline unsigned int make_flags(struct gdlm_lock *lp, if (lp->lksb.sb_lkid != 0) { lkf |= DLM_LKF_CONVERT; - - /* Conversion deadlock avoidance by DLM */ - - if (!(lp->ls->fsflags & LM_MFLAG_CONV_NODROP) && - !test_bit(LFL_FORCE_PROMOTE, &lp->flags) && - !(lkf & DLM_LKF_NOQUEUE) && - cur > DLM_LOCK_NL && req > DLM_LOCK_NL && cur != req) - lkf |= DLM_LKF_CONVDEADLK; } if (lp->lvb) @@ -173,14 +391,9 @@ static int gdlm_create_lp(struct gdlm_ls *ls, struct lm_lockname *name, make_strname(name, &lp->strname); lp->ls = ls; lp->cur = DLM_LOCK_IV; - lp->lvb = NULL; - lp->hold_null = NULL; - INIT_LIST_HEAD(&lp->clist); - INIT_LIST_HEAD(&lp->blist); INIT_LIST_HEAD(&lp->delay_list); spin_lock(&ls->async_lock); - list_add(&lp->all_list, &ls->all_locks); ls->all_locks_count++; spin_unlock(&ls->async_lock); @@ -188,26 +401,6 @@ static int gdlm_create_lp(struct gdlm_ls *ls, struct lm_lockname *name, return 0; } -void gdlm_delete_lp(struct gdlm_lock *lp) -{ - struct gdlm_ls *ls = lp->ls; - - spin_lock(&ls->async_lock); - if (!list_empty(&lp->clist)) - list_del_init(&lp->clist); - if (!list_empty(&lp->blist)) - list_del_init(&lp->blist); - if (!list_empty(&lp->delay_list)) - list_del_init(&lp->delay_list); - gdlm_assert(!list_empty(&lp->all_list), "%x,%llx", lp->lockname.ln_type, - (unsigned long long)lp->lockname.ln_number); - list_del_init(&lp->all_list); - ls->all_locks_count--; - spin_unlock(&ls->async_lock); - - kfree(lp); -} - int gdlm_get_lock(void *lockspace, struct lm_lockname *name, void **lockp) { @@ -261,7 +454,7 @@ unsigned int gdlm_do_lock(struct gdlm_lock *lp) if ((error == -EAGAIN) && (lp->lkf & DLM_LKF_NOQUEUE)) { lp->lksb.sb_status = -EAGAIN; - queue_complete(lp); + gdlm_ast(lp); error = 0; } @@ -308,6 +501,12 @@ unsigned int gdlm_lock(void *lock, unsigned int cur_state, { struct gdlm_lock *lp = lock; + if (req_state == LM_ST_UNLOCKED) + return gdlm_unlock(lock, cur_state); + + if (req_state == LM_ST_UNLOCKED) + return gdlm_unlock(lock, cur_state); + clear_bit(LFL_DLM_CANCEL, &lp->flags); if (flags & LM_FLAG_NOEXP) set_bit(LFL_NOBLOCK, &lp->flags); @@ -351,7 +550,7 @@ void gdlm_cancel(void *lock) if (delay_list) { set_bit(LFL_CANCEL, &lp->flags); set_bit(LFL_ACTIVE, &lp->flags); - queue_complete(lp); + gdlm_ast(lp); return; } @@ -507,22 +706,3 @@ void gdlm_submit_delayed(struct gdlm_ls *ls) wake_up(&ls->thread_wait); } -int gdlm_release_all_locks(struct gdlm_ls *ls) -{ - struct gdlm_lock *lp, *safe; - int count = 0; - - spin_lock(&ls->async_lock); - list_for_each_entry_safe(lp, safe, &ls->all_locks, all_list) { - list_del_init(&lp->all_list); - - if (lp->lvb && lp->lvb != junk_lvb) - kfree(lp->lvb); - kfree(lp); - count++; - } - spin_unlock(&ls->async_lock); - - return count; -} - |