lib/tdb2: fix OpenBSD incoherent mmap (tdb2 version)

This handles incoherent mmaps for TDB2 native databases, by forcing
mmap on for such systems, just like we did for tdb1.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

3 files changed, 31 insertions, 8 deletions

diff --git a/lib/tdb2/io.c b/lib/tdb2/io.c
index 5634922db3..e27a9fe832 100644
--- a/lib/tdb2/io.c
+++ b/lib/tdb2/io.c
@@ -40,15 +40,17 @@ void tdb_munmap(struct tdb_file *file)
 	}
 }
 
-void tdb_mmap(struct tdb_context *tdb)
+enum TDB_ERROR tdb_mmap(struct tdb_context *tdb)
 {
 	int mmap_flags;
 
 	if (tdb->flags & TDB_INTERNAL)
-		return;
+		return TDB_SUCCESS;
 
+#ifndef HAVE_INCOHERENT_MMAP
 	if (tdb->flags & TDB_NOMMAP)
-		return;
+		return TDB_SUCCESS;
+#endif
 
 	if ((tdb->open_flags & O_ACCMODE) == O_RDONLY)
 		mmap_flags = PROT_READ;
@@ -68,10 +70,19 @@ void tdb_mmap(struct tdb_context *tdb)
 	 */
 	if (tdb->file->map_ptr == MAP_FAILED) {
 		tdb->file->map_ptr = NULL;
+#ifdef HAVE_INCOHERENT_MMAP
+		/* Incoherent mmap means everyone must mmap! */
+		return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+				  "tdb_mmap failed for size %lld (%s)",
+				  (long long)tdb->file->map_size,
+				  strerror(errno));
+#else
 		tdb_logerr(tdb, TDB_SUCCESS, TDB_LOG_WARNING,
 			   "tdb_mmap failed for size %lld (%s)",
 			   (long long)tdb->file->map_size, strerror(errno));
+#endif
 	}
+	return TDB_SUCCESS;
 }
 
 /* check for an out of bounds access - if it is out of bounds then
@@ -143,8 +154,7 @@ static enum TDB_ERROR tdb_oob(struct tdb_context *tdb,
 	tdb_munmap(tdb->file);
 
 	tdb->file->map_size = st.st_size;
-	tdb_mmap(tdb);
-	return TDB_SUCCESS;
+	return tdb_mmap(tdb);
 }
 
 /* Endian conversion: we only ever deal with 8 byte quantities */
@@ -270,6 +280,9 @@ static enum TDB_ERROR tdb_write(struct tdb_context *tdb, tdb_off_t off,
 	if (tdb->file->map_ptr) {
 		memcpy(off + (char *)tdb->file->map_ptr, buf, len);
 	} else {
+#ifdef HAVE_INCOHERENT_MMAP
+		return TDB_ERR_IO;
+#else
 		ssize_t ret;
 		ret = pwrite(tdb->file->fd, buf, len, off);
 		if (ret != len) {
@@ -282,6 +295,7 @@ static enum TDB_ERROR tdb_write(struct tdb_context *tdb, tdb_off_t off,
 					  ret, (size_t)off, (size_t)len,
 					  strerror(errno));
 		}
+#endif
 	}
 	return TDB_SUCCESS;
 }
@@ -300,6 +314,9 @@ static enum TDB_ERROR tdb_read(struct tdb_context *tdb, tdb_off_t off,
 	if (tdb->file->map_ptr) {
 		memcpy(buf, off + (char *)tdb->file->map_ptr, len);
 	} else {
+#ifdef HAVE_INCOHERENT_MMAP
+		return TDB_ERR_IO;
+#else
 		ssize_t r = pread(tdb->file->fd, buf, len, off);
 		if (r != len) {
 			return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
@@ -309,6 +326,7 @@ static enum TDB_ERROR tdb_read(struct tdb_context *tdb, tdb_off_t off,
 					  strerror(errno),
 					  (size_t)tdb->file->map_size);
 		}
+#endif
 	}
 	return TDB_SUCCESS;
 }
@@ -439,6 +457,7 @@ static enum TDB_ERROR tdb_expand_file(struct tdb_context *tdb,
 		}
 		tdb->file->map_ptr = new;
 		tdb->file->map_size += addition;
+		return TDB_SUCCESS;
 	} else {
 		/* Unmap before trying to write; old TDB claimed OpenBSD had
 		 * problem with this otherwise. */
@@ -457,9 +476,8 @@ static enum TDB_ERROR tdb_expand_file(struct tdb_context *tdb,
 		if (ecode != TDB_SUCCESS)
 			return ecode;
 		tdb->file->map_size += addition;
-		tdb_mmap(tdb);
+		return tdb_mmap(tdb);
 	}
-	return TDB_SUCCESS;
 }
 
 const void *tdb_access_read(struct tdb_context *tdb,
diff --git a/lib/tdb2/private.h b/lib/tdb2/private.h
index 04a433be38..0ee8fa4f09 100644
--- a/lib/tdb2/private.h
+++ b/lib/tdb2/private.h
@@ -454,7 +454,7 @@ void *tdb_convert(const struct tdb_context *tdb, void *buf, tdb_len_t size);
 
 /* Unmap and try to map the tdb. */
 void tdb_munmap(struct tdb_file *file);
-void tdb_mmap(struct tdb_context *tdb);
+enum TDB_ERROR tdb_mmap(struct tdb_context *tdb);
 
 /* Either alloc a copy, or give direct access.  Release frees or noop. */
 const void *tdb_access_read(struct tdb_context *tdb,
diff --git a/lib/tdb2/tdb.c b/lib/tdb2/tdb.c
index c9224bdeed..4ba6924645 100644
--- a/lib/tdb2/tdb.c
+++ b/lib/tdb2/tdb.c
@@ -386,7 +386,9 @@ _PUBLIC_ void tdb_add_flag(struct tdb_context *tdb, unsigned flag)
 		break;
 	case TDB_NOMMAP:
 		tdb->flags |= TDB_NOMMAP;
+#ifndef HAVE_INCOHERENT_MMAP
 		tdb_munmap(tdb->file);
+#endif
 		break;
 	case TDB_NOSYNC:
 		tdb->flags |= TDB_NOSYNC;
@@ -423,7 +425,10 @@ _PUBLIC_ void tdb_remove_flag(struct tdb_context *tdb, unsigned flag)
 		break;
 	case TDB_NOMMAP:
 		tdb->flags &= ~TDB_NOMMAP;
+#ifndef HAVE_INCOHERENT_MMAP
+		/* If mmap incoherent, we were mmaping anyway. */
 		tdb_mmap(tdb);
+#endif
 		break;
 	case TDB_NOSYNC:
 		tdb->flags &= ~TDB_NOSYNC;