rbd: modify header, add utility to ease sync with qemu tree

src/include/rbd_types.h

@@ -22,9 +22,17 @@
 #define RBD_COMP_NONE		0
 #define RBD_CRYPT_NONE		0
 
+#define RBD_FLAGS_ORDER_MASK		0x000000FF
+#define RBD_FLAGS_CRYPT_TYPE_MASK	0x0000FF00
+#define RBD_FLAGS_COMP_TYPE_MASK	0x00FF0000
+
+#define RBD_FLAGS_ORDER_SHIFT		0
+#define RBD_FLAGS_CRYPT_TYPE_SHIFT	1
+#define RBD_FLAGS_COMP_TYPE_SHIFT	2
+
 static const char rbd_text[] = "<<< Rados Block Device Image >>>\n";
 static const char rbd_signature[] = "RBD";
-static const char rbd_version[] = "001.002";
+static const char rbd_version[] = "001.004";
 
 struct rbd_obj_snap_ondisk {
 	__le64 id;
@@ -35,14 +43,19 @@ struct rbd_obj_header_ondisk {
 	char text[64];
 	char signature[4];
 	char version[8];
+	__le32 flags;
 	__le64 image_size;
-	__u8 obj_order;
-	__u8 crypt_type;
-	__u8 comp_type;
 	__le64 snap_seq;
 	__le32 snap_count;
+	__le32 reserved;
 	__le64 snap_names_len;
 	struct rbd_obj_snap_ondisk snaps[0];
 } __attribute__((packed));
 
+
+static inline int rbd_get_obj_order(__u32 flags)
+{
+	return flags & RBD_FLAGS_ORDER_MASK;
+}
+
 #endif

src/push_to_qemu.pl

@@ -0,0 +1,21 @@
+#!/usr/bin/perl
+
+use strict;
+
+my $usage = "./push_to_qemu.pl <path_to_qemu>\n";
+
+my $qemu = shift @ARGV || die $usage;
+die $usage unless -d $qemu;
+
+die "not in a git tree" unless `cd $qemu && git rev-parse HEAD`;
+
+my $dir = '.';
+until (-d "$dir/.git") {
+    $dir .= "/..";
+}
+
+print "pushing changed shared files from $dir to $qemu...\n";
+system "cat $dir/src/include/rbd_types.h | sed 's/u32/uint32_t/g; s/__u8/uint8_t/g; s/__.*16/uint16_t/g; s/__.*32/uint32_t/g; s/__.*64/uint64_t/g; s/_FS_CEPH_RBD/QEMU_BLOCK_RBD_TYPES_H/g' | grep -v \"linux/types.h\" > $qemu/block/rbd_types.h";
+
+print "done.\n";
+

src/rbdtool.cc

@@ -57,31 +57,36 @@ static void init_rbd_header(struct rbd_obj_header_ondisk& ondisk,
   memcpy(&ondisk.version, rbd_version, sizeof(rbd_version));
 
   ondisk.image_size = size;
+  ondisk.flags = 0;
   if (order)
-    ondisk.obj_order = order;
+    ondisk.flags = order << RBD_FLAGS_ORDER_SHIFT;
   else
-    ondisk.obj_order = RBD_DEFAULT_OBJ_ORDER;
-  ondisk.crypt_type = RBD_CRYPT_NONE;
-  ondisk.comp_type = RBD_COMP_NONE;
+    ondisk.flags = RBD_DEFAULT_OBJ_ORDER;
+  ondisk.flags = ondisk.flags | (RBD_CRYPT_NONE << RBD_FLAGS_CRYPT_TYPE_SHIFT) |
+                 (RBD_COMP_NONE << RBD_FLAGS_COMP_TYPE_SHIFT);
   ondisk.snap_seq = 0;
   ondisk.snap_count = 0;
+  ondisk.reserved = 0;
   ondisk.snap_names_len = 0;
 }
 
 void print_header(char *imgname, rbd_obj_header_ondisk *header)
 {
+  int obj_order = rbd_get_obj_order(header->flags);
   cout << "rbd image '" << imgname << "':\n"
        << "\tsize " << prettybyte_t(header->image_size) << " in "
-       << (header->image_size >> header->obj_order) << " objects\n"
-       << "\torder " << (int)header->obj_order << " (" << prettybyte_t(1 << (header->obj_order)) << " objects)"
+       << (header->image_size >> obj_order) << " objects\n"
+       << "\torder " << obj_order
+       << " (" << prettybyte_t(1 << obj_order) << " objects)"
        << std::endl;
 }
 
 void trim_image(const char *imgname, rbd_obj_header_ondisk *header, uint64_t newsize)
 {
   uint64_t size = header->image_size;
-  uint64_t numseg = size >> header->obj_order;
-  uint64_t start = newsize >> header->obj_order;
+  int obj_order = rbd_get_obj_order(header->flags);
+  uint64_t numseg = size >> obj_order;
+  uint64_t start = newsize >> obj_order;
 
   cout << "trimming image data from " << numseg << " to " << start << " objects..." << std::endl;
   for (uint64_t i=start; i<numseg; i++) {