1 files changed, 64 insertions, 121 deletions

diff --git a/fs/dlm/user.c b/fs/dlm/user.c
index 66d6c16bf440..d5ab3fe7c198 100644
--- a/fs/dlm/user.c
+++ b/fs/dlm/user.c
@@ -24,6 +24,7 @@
 #include "lock.h"
 #include "lvb_table.h"
 #include "user.h"
+#include "ast.h"
 
 static const char name_prefix[] = "dlm";
 static const struct file_operations device_fops;
@@ -152,19 +153,16 @@ static void compat_output(struct dlm_lock_result *res,
    not related to the lifetime of the lkb struct which is managed
    entirely by refcount. */
 
-static int lkb_is_endoflife(struct dlm_lkb *lkb, int sb_status, int type)
+static int lkb_is_endoflife(int mode, int status)
 {
-	switch (sb_status) {
+	switch (status) {
 	case -DLM_EUNLOCK:
 		return 1;
 	case -DLM_ECANCEL:
 	case -ETIMEDOUT:
 	case -EDEADLK:
-		if (lkb->lkb_grmode == DLM_LOCK_IV)
-			return 1;
-		break;
 	case -EAGAIN:
-		if (type == AST_COMP && lkb->lkb_grmode == DLM_LOCK_IV)
+		if (mode == DLM_LOCK_IV)
 			return 1;
 		break;
 	}
@@ -174,12 +172,13 @@ static int lkb_is_endoflife(struct dlm_lkb *lkb, int sb_status, int type)
 /* we could possibly check if the cancel of an orphan has resulted in the lkb
    being removed and then remove that lkb from the orphans list and free it */
 
-void dlm_user_add_ast(struct dlm_lkb *lkb, int type, int mode)
+void dlm_user_add_ast(struct dlm_lkb *lkb, uint32_t flags, int mode,
+		      int status, uint32_t sbflags, uint64_t seq)
 {
 	struct dlm_ls *ls;
 	struct dlm_user_args *ua;
 	struct dlm_user_proc *proc;
-	int eol = 0, ast_type;
+	int rv;
 
 	if (lkb->lkb_flags & (DLM_IFL_ORPHAN | DLM_IFL_DEAD))
 		return;
@@ -200,49 +199,29 @@ void dlm_user_add_ast(struct dlm_lkb *lkb, int type, int mode)
 	ua = lkb->lkb_ua;
 	proc = ua->proc;
 
-	if (type == AST_BAST && ua->bastaddr == NULL)
+	if ((flags & DLM_CB_BAST) && ua->bastaddr == NULL)
 		goto out;
 
+	if ((flags & DLM_CB_CAST) && lkb_is_endoflife(mode, status))
+		lkb->lkb_flags |= DLM_IFL_ENDOFLIFE;
+
 	spin_lock(&proc->asts_spin);
 
-	ast_type = lkb->lkb_ast_type;
-	lkb->lkb_ast_type |= type;
-	if (type == AST_BAST)
-		lkb->lkb_bastmode = mode;
-	else
-		lkb->lkb_castmode = mode;
+	rv = dlm_add_lkb_callback(lkb, flags, mode, status, sbflags, seq);
+	if (rv < 0) {
+		spin_unlock(&proc->asts_spin);
+		goto out;
+	}
 
-	if (!ast_type) {
+	if (list_empty(&lkb->lkb_astqueue)) {
 		kref_get(&lkb->lkb_ref);
 		list_add_tail(&lkb->lkb_astqueue, &proc->asts);
-		lkb->lkb_ast_first = type;
 		wake_up_interruptible(&proc->wait);
 	}
-	if (type == AST_COMP && (ast_type & AST_COMP))
-		log_debug(ls, "ast overlap %x status %x %x",
-			  lkb->lkb_id, ua->lksb.sb_status, lkb->lkb_flags);
-
-	eol = lkb_is_endoflife(lkb, ua->lksb.sb_status, type);
-	if (eol) {
-		lkb->lkb_flags |= DLM_IFL_ENDOFLIFE;
-	}
-
-	/* We want to copy the lvb to userspace when the completion
-	   ast is read if the status is 0, the lock has an lvb and
-	   lvb_ops says we should.  We could probably have set_lvb_lock()
-	   set update_user_lvb instead and not need old_mode */
-
-	if ((lkb->lkb_ast_type & AST_COMP) &&
-	    (lkb->lkb_lksb->sb_status == 0) &&
-	    lkb->lkb_lksb->sb_lvbptr &&
-	    dlm_lvb_operations[ua->old_mode + 1][lkb->lkb_grmode + 1])
-		ua->update_user_lvb = 1;
-	else
-		ua->update_user_lvb = 0;
-
 	spin_unlock(&proc->asts_spin);
 
-	if (eol) {
+	if (lkb->lkb_flags & DLM_IFL_ENDOFLIFE) {
+		/* N.B. spin_lock locks_spin, not asts_spin */
 		spin_lock(&proc->locks_spin);
 		if (!list_empty(&lkb->lkb_ownqueue)) {
 			list_del_init(&lkb->lkb_ownqueue);
@@ -705,8 +684,9 @@ static int device_close(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static int copy_result_to_user(struct dlm_user_args *ua, int compat, int type,
-			       int mode, char __user *buf, size_t count)
+static int copy_result_to_user(struct dlm_user_args *ua, int compat,
+			       uint32_t flags, int mode, int copy_lvb,
+			       char __user *buf, size_t count)
 {
 #ifdef CONFIG_COMPAT
 	struct dlm_lock_result32 result32;
@@ -730,7 +710,7 @@ static int copy_result_to_user(struct dlm_user_args *ua, int compat, int type,
 	   notes that a new blocking AST address and parameter are set even if
 	   the conversion fails, so maybe we should just do that. */
 
-	if (type == AST_BAST) {
+	if (flags & DLM_CB_BAST) {
 		result.user_astaddr = ua->bastaddr;
 		result.user_astparam = ua->bastparam;
 		result.bast_mode = mode;
@@ -750,8 +730,7 @@ static int copy_result_to_user(struct dlm_user_args *ua, int compat, int type,
 	/* copy lvb to userspace if there is one, it's been updated, and
 	   the user buffer has space for it */
 
-	if (ua->update_user_lvb && ua->lksb.sb_lvbptr &&
-	    count >= len + DLM_USER_LVB_LEN) {
+	if (copy_lvb && ua->lksb.sb_lvbptr && count >= len + DLM_USER_LVB_LEN) {
 		if (copy_to_user(buf+len, ua->lksb.sb_lvbptr,
 				 DLM_USER_LVB_LEN)) {
 			error = -EFAULT;
@@ -801,13 +780,12 @@ static ssize_t device_read(struct file *file, char __user *buf, size_t count,
 	struct dlm_user_proc *proc = file->private_data;
 	struct dlm_lkb *lkb;
 	DECLARE_WAITQUEUE(wait, current);
-	int error = 0, removed;
-	int ret_type, ret_mode;
-	int bastmode, castmode, do_bast, do_cast;
+	struct dlm_callback cb;
+	int rv, resid, copy_lvb = 0;
 
 	if (count == sizeof(struct dlm_device_version)) {
-		error = copy_version_to_user(buf, count);
-		return error;
+		rv = copy_version_to_user(buf, count);
+		return rv;
 	}
 
 	if (!proc) {
@@ -854,92 +832,57 @@ static ssize_t device_read(struct file *file, char __user *buf, size_t count,
 		}
 	}
 
-	/* there may be both completion and blocking asts to return for
-	   the lkb, don't remove lkb from asts list unless no asts remain */
+	/* if we empty lkb_callbacks, we don't want to unlock the spinlock
+	   without removing lkb_astqueue; so empty lkb_astqueue is always
+	   consistent with empty lkb_callbacks */
 
 	lkb = list_entry(proc->asts.next, struct dlm_lkb, lkb_astqueue);
 
-	removed = 0;
-	ret_type = 0;
-	ret_mode = 0;
-	do_bast = lkb->lkb_ast_type & AST_BAST;
-	do_cast = lkb->lkb_ast_type & AST_COMP;
-	bastmode = lkb->lkb_bastmode;
-	castmode = lkb->lkb_castmode;
-
-	/* when both are queued figure out which to do first and
-	   switch first so the other goes in the next read */
-
-	if (do_cast && do_bast) {
-		if (lkb->lkb_ast_first == AST_COMP) {
-			ret_type = AST_COMP;
-			ret_mode = castmode;
-			lkb->lkb_ast_type &= ~AST_COMP;
-			lkb->lkb_ast_first = AST_BAST;
-		} else {
-			ret_type = AST_BAST;
-			ret_mode = bastmode;
-			lkb->lkb_ast_type &= ~AST_BAST;
-			lkb->lkb_ast_first = AST_COMP;
-		}
-	} else {
-		ret_type = lkb->lkb_ast_first;
-		ret_mode = (ret_type == AST_COMP) ? castmode : bastmode;
-		lkb->lkb_ast_type &= ~ret_type;
-		lkb->lkb_ast_first = 0;
+	rv = dlm_rem_lkb_callback(lkb->lkb_resource->res_ls, lkb, &cb, &resid);
+	if (rv < 0) {
+		/* this shouldn't happen; lkb should have been removed from
+		   list when resid was zero */
+		log_print("dlm_rem_lkb_callback empty %x", lkb->lkb_id);
+		list_del_init(&lkb->lkb_astqueue);
+		spin_unlock(&proc->asts_spin);
+		/* removes ref for proc->asts, may cause lkb to be freed */
+		dlm_put_lkb(lkb);
+		goto try_another;
 	}
+	if (!resid)
+		list_del_init(&lkb->lkb_astqueue);
+	spin_unlock(&proc->asts_spin);
 
-	/* if we're doing a bast but the bast is unnecessary, then
-	   switch to do nothing or do a cast if that was needed next */
-
-	if ((ret_type == AST_BAST) &&
-	    dlm_modes_compat(bastmode, lkb->lkb_castmode_done)) {
-		ret_type = 0;
-		ret_mode = 0;
-
-		if (do_cast) {
-			ret_type = AST_COMP;
-			ret_mode = castmode;
-			lkb->lkb_ast_type &= ~AST_COMP;
-			lkb->lkb_ast_first = 0;
-		}
+	if (cb.flags & DLM_CB_SKIP) {
+		/* removes ref for proc->asts, may cause lkb to be freed */
+		if (!resid)
+			dlm_put_lkb(lkb);
+		goto try_another;
 	}
 
-	if (lkb->lkb_ast_first != lkb->lkb_ast_type) {
-		log_print("device_read %x ast_first %x ast_type %x",
-			  lkb->lkb_id, lkb->lkb_ast_first, lkb->lkb_ast_type);
-	}
+	if (cb.flags & DLM_CB_CAST) {
+		int old_mode, new_mode;
 
-	if (!lkb->lkb_ast_type) {
-		list_del(&lkb->lkb_astqueue);
-		removed = 1;
-	}
-	spin_unlock(&proc->asts_spin);
+		old_mode = lkb->lkb_last_cast.mode;
+		new_mode = cb.mode;
 
-	if (ret_type) {
-		error = copy_result_to_user(lkb->lkb_ua,
-				test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags),
-				ret_type, ret_mode, buf, count);
+		if (!cb.sb_status && lkb->lkb_lksb->sb_lvbptr &&
+		    dlm_lvb_operations[old_mode + 1][new_mode + 1])
+			copy_lvb = 1;
 
-		if (ret_type == AST_COMP)
-			lkb->lkb_castmode_done = castmode;
-		if (ret_type == AST_BAST)
-			lkb->lkb_bastmode_done = bastmode;
+		lkb->lkb_lksb->sb_status = cb.sb_status;
+		lkb->lkb_lksb->sb_flags = cb.sb_flags;
 	}
 
-	/* removes reference for the proc->asts lists added by
-	   dlm_user_add_ast() and may result in the lkb being freed */
+	rv = copy_result_to_user(lkb->lkb_ua,
+				 test_bit(DLM_PROC_FLAGS_COMPAT, &proc->flags),
+				 cb.flags, cb.mode, copy_lvb, buf, count);
 
-	if (removed)
+	/* removes ref for proc->asts, may cause lkb to be freed */
+	if (!resid)
 		dlm_put_lkb(lkb);
 
-	/* the bast that was queued was eliminated (see unnecessary above),
-	   leaving nothing to return */
-
-	if (!ret_type)
-		goto try_another;
-
-	return error;
+	return rv;
 }
 
 static unsigned int device_poll(struct file *file, poll_table *wait)