[PATCH v3 4/6] ebpf: Added declaration/initialization routines.

[Andrew Melnychenko <andrew@daynix.com>]

Now, the binary objects may be retrieved by id.
It would require for future qmp commands that may require specific
eBPF blob.

Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
 ebpf/ebpf.c      | 70 ++++++++++++++++++++++++++++++++++++++++++++++++
 ebpf/ebpf.h      | 31 +++++++++++++++++++++
 ebpf/ebpf_rss.c  |  6 +++++
 ebpf/meson.build |  2 +-
 4 files changed, 108 insertions(+), 1 deletion(-)
 create mode 100644 ebpf/ebpf.c
 create mode 100644 ebpf/ebpf.h

diff --git a/ebpf/ebpf.c b/ebpf/ebpf.c
new file mode 100644
index 00000000000..ea97c0403ee
--- /dev/null
+++ b/ebpf/ebpf.c
@@ -0,0 +1,70 @@
+/*
+ * QEMU eBPF binary declaration routine.
+ *
+ * Developed by Daynix Computing LTD (http://www.daynix.com)
+ *
+ * Authors:
+ *  Andrew Melnychenko <andrew@daynix.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/queue.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-ebpf.h"
+#include "ebpf/ebpf.h"
+
+struct ElfBinaryDataEntry {
+    int id;
+    const void *data;
+    size_t datalen;
+
+    QSLIST_ENTRY(ElfBinaryDataEntry) node;
+};
+
+static QSLIST_HEAD(, ElfBinaryDataEntry) ebpf_elf_obj_list =
+                                            QSLIST_HEAD_INITIALIZER();
+
+void ebpf_register_binary_data(int id, const void *data, size_t datalen)
+{
+    struct ElfBinaryDataEntry *dataentry = NULL;
+
+    dataentry = g_new0(struct ElfBinaryDataEntry, 1);
+    dataentry->data = data;
+    dataentry->datalen = datalen;
+    dataentry->id = id;
+
+    QSLIST_INSERT_HEAD(&ebpf_elf_obj_list, dataentry, node);
+}
+
+const void *ebpf_find_binary_by_id(int id, size_t *sz, Error **errp)
+{
+    struct ElfBinaryDataEntry *it = NULL;
+    QSLIST_FOREACH(it, &ebpf_elf_obj_list, node) {
+        if (id == it->id) {
+            *sz = it->datalen;
+            return it->data;
+        }
+    }
+
+    error_setg(errp, "can't find eBPF object with id: %d", id);
+
+    return NULL;
+}
+
+EbpfObject *qmp_request_ebpf(EbpfProgramID id, Error **errp)
+{
+    EbpfObject *ret = NULL;
+    size_t size = 0;
+    const void *data = ebpf_find_binary_by_id(id, &size, errp);
+    if (!data) {
+        return NULL;
+    }
+
+    ret = g_new0(EbpfObject, 1);
+    ret->object = g_base64_encode(data, size);
+
+    return ret;
+}
diff --git a/ebpf/ebpf.h b/ebpf/ebpf.h
new file mode 100644
index 00000000000..b6266b28b8c
--- /dev/null
+++ b/ebpf/ebpf.h
@@ -0,0 +1,31 @@
+/*
+ * QEMU eBPF binary declaration routine.
+ *
+ * Developed by Daynix Computing LTD (http://www.daynix.com)
+ *
+ * Authors:
+ *  Andrew Melnychenko <andrew@daynix.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ */
+
+#ifndef EBPF_H
+#define EBPF_H
+
+struct Error;
+
+void ebpf_register_binary_data(int id, const void *data,
+                               size_t datalen);
+const void *ebpf_find_binary_by_id(int id, size_t *sz,
+                                   struct Error **errp);
+
+#define ebpf_binary_init(id, fn)                                           \
+static void __attribute__((constructor)) ebpf_binary_init_ ## fn(void)     \
+{                                                                          \
+    size_t datalen = 0;                                                    \
+    const void *data = fn(&datalen);                                       \
+    ebpf_register_binary_data(id, data, datalen);                          \
+}
+
+#endif /* EBPF_H */
diff --git a/ebpf/ebpf_rss.c b/ebpf/ebpf_rss.c
index 24bc6cc409e..8679dc452df 100644
--- a/ebpf/ebpf_rss.c
+++ b/ebpf/ebpf_rss.c
@@ -13,6 +13,8 @@
 
 #include "qemu/osdep.h"
 #include "qemu/error-report.h"
+#include "qapi/qapi-types-misc.h"
+#include "qapi/qapi-commands-ebpf.h"
 
 #include <bpf/libbpf.h>
 #include <bpf/bpf.h>
@@ -21,6 +23,8 @@
 
 #include "ebpf/ebpf_rss.h"
 #include "ebpf/rss.bpf.skeleton.h"
+#include "ebpf/ebpf.h"
+
 #include "trace.h"
 
 void ebpf_rss_init(struct EBPFRSSContext *ctx)
@@ -261,3 +265,5 @@ void ebpf_rss_unload(struct EBPFRSSContext *ctx)
     ctx->map_toeplitz_key = -1;
     ctx->map_indirections_table = -1;
 }
+
+ebpf_binary_init(EBPF_PROGRAMID_RSS, rss_bpf__elf_bytes)
diff --git a/ebpf/meson.build b/ebpf/meson.build
index 2dd0fd89480..272ec2d5311 100644
--- a/ebpf/meson.build
+++ b/ebpf/meson.build
@@ -1 +1 @@
-softmmu_ss.add(when: libbpf, if_true: files('ebpf_rss.c'), if_false: files('ebpf_rss-stub.c'))
+softmmu_ss.add(when: libbpf, if_true: files('ebpf.c', 'ebpf_rss.c'), if_false: files('ebpf_rss-stub.c'))
-- 
2.39.1