dlm: record full callback state

Change how callbacks are recorded for locks.  Previously, information
about multiple callbacks was combined into a couple of variables that
indicated what the end result should be.  In some situations, we
could not tell from this combined state what the exact sequence of
callbacks were, and would end up either delivering the callbacks in
the wrong order, or suppress redundant callbacks incorrectly.  This
new approach records all the data for each callback, leaving no
uncertainty about what needs to be delivered.

Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 17 insertions, 21 deletions

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 64e5f3efdd8..04b8c449303 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -160,10 +160,10 @@ static const int __quecvt_compat_matrix[8][8] = {
 void dlm_print_lkb(struct dlm_lkb *lkb)
 {
 	printk(KERN_ERR "lkb: nodeid %d id %x remid %x exflags %x flags %x\n"
-	       "     status %d rqmode %d grmode %d wait_type %d ast_type %d\n",
+	       "     status %d rqmode %d grmode %d wait_type %d\n",
 	       lkb->lkb_nodeid, lkb->lkb_id, lkb->lkb_remid, lkb->lkb_exflags,
 	       lkb->lkb_flags, lkb->lkb_status, lkb->lkb_rqmode,
-	       lkb->lkb_grmode, lkb->lkb_wait_type, lkb->lkb_ast_type);
+	       lkb->lkb_grmode, lkb->lkb_wait_type);
 }
 
 static void dlm_print_rsb(struct dlm_rsb *r)
@@ -305,10 +305,7 @@ static void queue_cast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rv)
 		rv = -EDEADLK;
 	}
 
-	lkb->lkb_lksb->sb_status = rv;
-	lkb->lkb_lksb->sb_flags = lkb->lkb_sbflags;
-
-	dlm_add_ast(lkb, AST_COMP, lkb->lkb_grmode);
+	dlm_add_ast(lkb, DLM_CB_CAST, lkb->lkb_grmode, rv, lkb->lkb_sbflags);
 }
 
 static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
@@ -319,13 +316,10 @@ static inline void queue_cast_overlap(struct dlm_rsb *r, struct dlm_lkb *lkb)
 
 static void queue_bast(struct dlm_rsb *r, struct dlm_lkb *lkb, int rqmode)
 {
-	lkb->lkb_time_bast = ktime_get();
-
 	if (is_master_copy(lkb)) {
-		lkb->lkb_bastmode = rqmode; /* printed by debugfs */
 		send_bast(r, lkb, rqmode);
 	} else {
-		dlm_add_ast(lkb, AST_BAST, rqmode);
+		dlm_add_ast(lkb, DLM_CB_BAST, rqmode, 0, 0);
 	}
 }
 
@@ -600,6 +594,7 @@ static int create_lkb(struct dlm_ls *ls, struct dlm_lkb **lkb_ret)
 	INIT_LIST_HEAD(&lkb->lkb_ownqueue);
 	INIT_LIST_HEAD(&lkb->lkb_rsb_lookup);
 	INIT_LIST_HEAD(&lkb->lkb_time_list);
+	INIT_LIST_HEAD(&lkb->lkb_astqueue);
 
 	get_random_bytes(&bucket, sizeof(bucket));
 	bucket &= (ls->ls_lkbtbl_size - 1);
@@ -2819,9 +2814,9 @@ static void send_args(struct dlm_rsb *r, struct dlm_lkb *lkb,
 	   not from lkb fields */
 
 	if (lkb->lkb_bastfn)
-		ms->m_asts |= AST_BAST;
+		ms->m_asts |= DLM_CB_BAST;
 	if (lkb->lkb_astfn)
-		ms->m_asts |= AST_COMP;
+		ms->m_asts |= DLM_CB_CAST;
 
 	/* compare with switch in create_message; send_remove() doesn't
 	   use send_args() */
@@ -3122,8 +3117,8 @@ static int receive_request_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
 	lkb->lkb_grmode = DLM_LOCK_IV;
 	lkb->lkb_rqmode = ms->m_rqmode;
 
-	lkb->lkb_bastfn = (ms->m_asts & AST_BAST) ? &fake_bastfn : NULL;
-	lkb->lkb_astfn = (ms->m_asts & AST_COMP) ? &fake_astfn : NULL;
+	lkb->lkb_bastfn = (ms->m_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
+	lkb->lkb_astfn = (ms->m_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
 
 	if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
 		/* lkb was just created so there won't be an lvb yet */
@@ -4412,8 +4407,8 @@ static int receive_rcom_lock_args(struct dlm_ls *ls, struct dlm_lkb *lkb,
 	lkb->lkb_grmode = rl->rl_grmode;
 	/* don't set lkb_status because add_lkb wants to itself */
 
-	lkb->lkb_bastfn = (rl->rl_asts & AST_BAST) ? &fake_bastfn : NULL;
-	lkb->lkb_astfn = (rl->rl_asts & AST_COMP) ? &fake_astfn : NULL;
+	lkb->lkb_bastfn = (rl->rl_asts & DLM_CB_BAST) ? &fake_bastfn : NULL;
+	lkb->lkb_astfn = (rl->rl_asts & DLM_CB_CAST) ? &fake_astfn : NULL;
 
 	if (lkb->lkb_exflags & DLM_LKF_VALBLK) {
 		int lvblen = rc->rc_header.h_length - sizeof(struct dlm_rcom) -
@@ -4589,7 +4584,6 @@ int dlm_user_request(struct dlm_ls *ls, struct dlm_user_args *ua,
 	error = set_lock_args(mode, &ua->lksb, flags, namelen, timeout_cs,
 			      fake_astfn, ua, fake_bastfn, &args);
 	lkb->lkb_flags |= DLM_IFL_USER;
-	ua->old_mode = DLM_LOCK_IV;
 
 	if (error) {
 		__put_lkb(ls, lkb);
@@ -4658,7 +4652,6 @@ int dlm_user_convert(struct dlm_ls *ls, struct dlm_user_args *ua_tmp,
 	ua->bastparam = ua_tmp->bastparam;
 	ua->bastaddr = ua_tmp->bastaddr;
 	ua->user_lksb = ua_tmp->user_lksb;
-	ua->old_mode = lkb->lkb_grmode;
 
 	error = set_lock_args(mode, &ua->lksb, flags, 0, timeout_cs,
 			      fake_astfn, ua, fake_bastfn, &args);
@@ -4917,8 +4910,9 @@ void dlm_clear_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
 	}
 
 	list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_astqueue) {
-		lkb->lkb_ast_type = 0;
-		list_del(&lkb->lkb_astqueue);
+		memset(&lkb->lkb_callbacks, 0,
+		       sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
+		list_del_init(&lkb->lkb_astqueue);
 		dlm_put_lkb(lkb);
 	}
 
@@ -4958,7 +4952,9 @@ static void purge_proc_locks(struct dlm_ls *ls, struct dlm_user_proc *proc)
 
 	spin_lock(&proc->asts_spin);
 	list_for_each_entry_safe(lkb, safe, &proc->asts, lkb_astqueue) {
-		list_del(&lkb->lkb_astqueue);
+		memset(&lkb->lkb_callbacks, 0,
+		       sizeof(struct dlm_callback) * DLM_CALLBACKS_SIZE);
+		list_del_init(&lkb->lkb_astqueue);
 		dlm_put_lkb(lkb);
 	}
 	spin_unlock(&proc->asts_spin);