docs: move rate_cycle description

[fio.git] / lib / pattern.h

diff --git a/lib/pattern.h b/lib/pattern.h
index a6d9d6b4275cf863c86c0b9978fa4dd36b239e80..7123b42d6747bc2cecc55a61b79389d0d6587f5d 100644 (file)
--- a/lib/pattern.h
+++ b/lib/pattern.h
@@ -1,6 +1,19 @@
 #ifndef FIO_PARSE_PATTERN_H
 #define FIO_PARSE_PATTERN_H
 
+/*
+ * The pattern is dynamically allocated, but that doesn't mean there
+ * are not limits. The network protocol has a limit of
+ * FIO_SERVER_MAX_CMD_MB and potentially two patterns must fit in there.
+ * There's also a need to verify the incoming data from the network and
+ * this provides a sensible check.
+ *
+ * 128MiB is an arbitrary limit that meets these criteria. The patterns
+ * tend to be truncated at the IO size anyway and IO sizes that large
+ * aren't terribly practical.
+ */
+#define MAX_PATTERN_SIZE       (128 << 20)
+
 /**
  * Pattern format description. The input for 'parse_pattern'.
  * Describes format with its name and callback, which should
@@ -21,11 +34,9 @@ struct pattern_fmt {
        const struct pattern_fmt_desc *desc;
 };
 
-int parse_and_fill_pattern(const char *in, unsigned int in_len,
-                          char *out, unsigned int out_len,
-                          const struct pattern_fmt_desc *fmt_desc,
-                          struct pattern_fmt *fmt,
-                          unsigned int *fmt_sz_out);
+int parse_and_fill_pattern_alloc(const char *in, unsigned int in_len,
+               char **out, const struct pattern_fmt_desc *fmt_desc,
+               struct pattern_fmt *fmt, unsigned int *fmt_sz_out);
 
 int paste_format_inplace(char *pattern, unsigned int pattern_len,
                         struct pattern_fmt *fmt, unsigned int fmt_sz,