smbd: Remove FAKE_LEVEL_II_OPLOCK

FAKE_LEVEL_II_OPLOCK was an indicator to break level2 oplock holders
on write.  This information is now being held in brlock.tdb, which makes
the FAKE_LEVEL_II_OPLOCK type unnecessary.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

5 files changed, 81 insertions, 59 deletions

diff --git a/source3/include/smb.h b/source3/include/smb.h
index 0d07f71750..5c0dfdcbc8 100644
--- a/source3/include/smb.h
+++ b/source3/include/smb.h
@@ -686,7 +686,8 @@ enum remote_arch_types {RA_UNKNOWN, RA_WFWG, RA_OS2, RA_WIN95, RA_WINNT,
 
 /* The following are Samba-private. */
 #define INTERNAL_OPEN_ONLY 		0x8
-#define FAKE_LEVEL_II_OPLOCK 		0x10	/* Client requested no_oplock, but we have to
+/* #define FAKE_LEVEL_II_OPLOCK 	0x10 */	  /* Not used anymore */
+				/* Client requested no_oplock, but we have to
 				 * inform potential level2 holders on
 				 * write. */
 /* #define DEFERRED_OPEN_ENTRY 		0x20 */   /* Not used anymore */
@@ -698,7 +699,7 @@ enum remote_arch_types {RA_UNKNOWN, RA_WFWG, RA_OS2, RA_WIN95, RA_WINNT,
 
 #define EXCLUSIVE_OPLOCK_TYPE(lck) ((lck) & ((unsigned int)EXCLUSIVE_OPLOCK|(unsigned int)BATCH_OPLOCK))
 #define BATCH_OPLOCK_TYPE(lck) ((lck) & (unsigned int)BATCH_OPLOCK)
-#define LEVEL_II_OPLOCK_TYPE(lck) ((lck) & ((unsigned int)LEVEL_II_OPLOCK|(unsigned int)FAKE_LEVEL_II_OPLOCK))
+#define LEVEL_II_OPLOCK_TYPE(lck) ((lck) & (unsigned int)LEVEL_II_OPLOCK)
 
 /* kernel_oplock_message definition.
 
diff --git a/source3/locking/locking.c b/source3/locking/locking.c
index b9db27cb86..7ac04a45e3 100644
--- a/source3/locking/locking.c
+++ b/source3/locking/locking.c
@@ -823,19 +823,7 @@ bool remove_share_oplock(struct share_mode_lock *lck, files_struct *fsp)
 		return False;
 	}
 
-	if (EXCLUSIVE_OPLOCK_TYPE(e->op_type)) {
-		/*
-		 * Going from exclusive or batch,
- 		 * we always go through FAKE_LEVEL_II
- 		 * first.
- 		 */
-		if (!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
-			smb_panic("remove_share_oplock: logic error");
-		}
-		e->op_type = FAKE_LEVEL_II_OPLOCK;
-	} else {
-		e->op_type = NO_OPLOCK;
-	}
+	e->op_type = NO_OPLOCK;
 	lck->data->modified = True;
 	return True;
 }
diff --git a/source3/smbd/files.c b/source3/smbd/files.c
index d94ee11952..c64c84173c 100644
--- a/source3/smbd/files.c
+++ b/source3/smbd/files.c
@@ -318,8 +318,7 @@ files_struct *file_find_dif(struct smbd_server_connection *sconn,
 			}
 			/* Paranoia check. */
 			if ((fsp->fh->fd == -1) &&
-			    (fsp->oplock_type != NO_OPLOCK) &&
-			    (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK)) {
+			    (fsp->oplock_type != NO_OPLOCK)) {
 				DEBUG(0,("file_find_dif: file %s file_id = "
 					 "%s, gen = %u oplock_type = %u is a "
 					 "stat open with oplock type !\n",
diff --git a/source3/smbd/open.c b/source3/smbd/open.c
index f6df03595f..93b69d5afd 100644
--- a/source3/smbd/open.c
+++ b/source3/smbd/open.c
@@ -1052,14 +1052,6 @@ static void validate_my_share_entries(struct smbd_server_connection *sconn,
 			  "share entry with an open file\n");
 	}
 
-	if ((share_entry->op_type == NO_OPLOCK) &&
-	    (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK))
-	{
-		/* Someone has already written to it, but I haven't yet
-		 * noticed */
-		return;
-	}
-
 	if (((uint16)fsp->oplock_type) != share_entry->op_type) {
 		goto panic;
 	}
@@ -1408,24 +1400,10 @@ static void grant_fsp_oplock_type(files_struct *fsp,
  	 * what was found in the existing share modes.
  	 */
 
-	if (got_a_none_oplock) {
-		fsp->oplock_type = NO_OPLOCK;
-	} else if (got_level2_oplock) {
-		if (fsp->oplock_type == NO_OPLOCK ||
-				fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
-			/* Store a level2 oplock, but don't tell the client */
-			fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
-		} else {
+	if (got_level2_oplock || got_a_none_oplock) {
+		if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
 			fsp->oplock_type = LEVEL_II_OPLOCK;
 		}
-	} else {
-		/* All share_mode_entries are placeholders or deferred.
-		 * Silently upgrade to fake levelII if the client didn't
-		 * ask for an oplock. */
-		if (fsp->oplock_type == NO_OPLOCK) {
-			/* Store a level2 oplock, but don't tell the client */
-			fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
-		}
 	}
 
 	/*
@@ -1433,7 +1411,20 @@ static void grant_fsp_oplock_type(files_struct *fsp,
 	 * or if we've turned them off.
 	 */
 	if (fsp->oplock_type == LEVEL_II_OPLOCK && !allow_level2) {
-		fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
+		fsp->oplock_type = NO_OPLOCK;
+	}
+
+	if (fsp->oplock_type == LEVEL_II_OPLOCK && !got_level2_oplock) {
+		/*
+		 * We're the first level2 oplock. Indicate that in brlock.tdb.
+		 */
+		struct byte_range_lock *brl;
+
+		brl = brl_get_locks(talloc_tos(), fsp);
+		if (brl != NULL) {
+			brl_set_have_read_oplocks(brl, true);
+			TALLOC_FREE(brl);
+		}
 	}
 
 	DEBUG(10,("grant_fsp_oplock_type: oplock type 0x%x on file %s\n",
diff --git a/source3/smbd/oplock.c b/source3/smbd/oplock.c
index 70f168ed72..f18ac657b8 100644
--- a/source3/smbd/oplock.c
+++ b/source3/smbd/oplock.c
@@ -66,7 +66,6 @@ NTSTATUS set_file_oplock(files_struct *fsp, int oplock_type)
 	}
 
 	if ((fsp->oplock_type != NO_OPLOCK) &&
-	    (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 	    use_kernel &&
 	    !koplocks->ops->set_oplock(koplocks, fsp, oplock_type))
 	{
@@ -100,7 +99,6 @@ void release_file_oplock(files_struct *fsp)
 	struct kernel_oplocks *koplocks = sconn->oplocks.kernel_ops;
 
 	if ((fsp->oplock_type != NO_OPLOCK) &&
-	    (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
 	    koplocks) {
 		koplocks->ops->release_oplock(koplocks, fsp, NO_OPLOCK);
 	}
@@ -114,12 +112,7 @@ void release_file_oplock(files_struct *fsp)
 	SMB_ASSERT(sconn->oplocks.exclusive_open>=0);
 	SMB_ASSERT(sconn->oplocks.level_II_open>=0);
 
-	if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
-		/* This doesn't matter for close. */
-		fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
-	} else {
-		fsp->oplock_type = NO_OPLOCK;
-	}
+	fsp->oplock_type = NO_OPLOCK;
 	fsp->sent_oplock_break = NO_BREAK_SENT;
 
 	flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
@@ -171,6 +164,45 @@ bool remove_oplock(files_struct *fsp)
 			 "file %s\n", fsp_str_dbg(fsp)));
 		return False;
 	}
+
+	if (fsp->oplock_type == LEVEL_II_OPLOCK) {
+
+		/*
+		 * If we're the only LEVEL_II holder, we have to remove the
+		 * have_read_oplocks from the brlock entry
+		 */
+
+		struct share_mode_data *data = lck->data;
+		uint32_t i, num_level2;
+
+		num_level2 = 0;
+		for (i=0; i<data->num_share_modes; i++) {
+			if (data->share_modes[i].op_type == LEVEL_II_OPLOCK) {
+				num_level2 += 1;
+			}
+			if (num_level2 > 1) {
+				/*
+				 * No need to count them all...
+				 */
+				break;
+			}
+		}
+
+		if (num_level2 == 1) {
+			/*
+			 * That's only us. We are dropping that level2 oplock,
+			 * so remove the brlock flag.
+			 */
+			struct byte_range_lock *brl;
+
+			brl = brl_get_locks(talloc_tos(), fsp);
+			if (brl) {
+				brl_set_have_read_oplocks(brl, false);
+				TALLOC_FREE(brl);
+			}
+		}
+	}
+
 	ret = remove_share_oplock(lck, fsp);
 	if (!ret) {
 		DEBUG(0,("remove_oplock: failed to remove share oplock for "
@@ -190,6 +222,7 @@ bool downgrade_oplock(files_struct *fsp)
 {
 	bool ret;
 	struct share_mode_lock *lck;
+	struct byte_range_lock *brl;
 
 	lck = get_existing_share_mode_lock(talloc_tos(), fsp->file_id);
 	if (lck == NULL) {
@@ -206,6 +239,13 @@ bool downgrade_oplock(files_struct *fsp)
 	}
 
 	downgrade_file_oplock(fsp);
+
+	brl = brl_get_locks(talloc_tos(), fsp);
+	if (brl != NULL) {
+		brl_set_have_read_oplocks(brl, true);
+		TALLOC_FREE(brl);
+	}
+
 	TALLOC_FREE(lck);
 	return ret;
 }
@@ -375,14 +415,6 @@ static void break_level2_to_none_async(files_struct *fsp)
 		return;
 	}
 
-	if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
-		/* Don't tell the client, just downgrade. */
-		DEBUG(3, ("process_oplock_async_level2_break_message: "
-			  "downgrading fake level 2 oplock.\n"));
-		remove_oplock(fsp);
-		return;
-	}
-
 	/* Ensure we're really at level2 state. */
 	SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
 
@@ -622,6 +654,7 @@ static void contend_level2_oplocks_begin_default(files_struct *fsp,
 	struct smbd_server_connection *sconn = fsp->conn->sconn;
 	struct tevent_immediate *im;
 	struct break_to_none_state *state;
+	struct byte_range_lock *brl;
 
 	/*
 	 * If this file is level II oplocked then we need
@@ -631,8 +664,18 @@ static void contend_level2_oplocks_begin_default(files_struct *fsp,
 	 * the shared memory area whilst doing this.
 	 */
 
-	if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
+	if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
+		/*
+		 * There can't be any level2 oplocks, we're alone.
+		 */
 		return;
+	}
+
+	brl = brl_get_locks_readonly(fsp);
+	if ((brl != NULL) && !brl_have_read_oplocks(brl)) {
+		DEBUG(10, ("No read oplocks around\n"));
+		return;
+	}
 
 	/*
 	 * When we get here we might have a brlock entry locked. Also