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path: root/fs/gfs2/locking/dlm/lock.c
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Diffstat (limited to 'fs/gfs2/locking/dlm/lock.c')
-rw-r--r--fs/gfs2/locking/dlm/lock.c368
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;
-}
-