[sheepdog] [PATCH] dog: fix to calculate a resizable max VDI size appropriately

[Teruaki Ishizaki]

A resizable max VDI size was fixed value, 4TB.

So, when block_size_shift was specified more than 22,
resizing VDI size over 4TB caused error.

This patch enables to calculate a resizable max VDI properly.

Signed-off-by: Teruaki Ishizaki <ishizaki.teruaki at lab.ntt.co.jp>
---
 dog/vdi.c |   24 +++++++++++++++---------
 1 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/dog/vdi.c b/dog/vdi.c
index 6cb813e..8e5ab13 100644
--- a/dog/vdi.c
+++ b/dog/vdi.c
@@ -845,8 +845,8 @@ out:
 static int vdi_resize(int argc, char **argv)
 {
 	const char *vdiname = argv[optind++];
-	uint64_t new_size;
-	uint32_t vid;
+	uint64_t new_size, old_max_total_size;
+	uint32_t vid, object_size;
 	int ret;
 	char buf[SD_INODE_HEADER_SIZE];
 	struct sd_inode *inode = (struct sd_inode *)buf;
@@ -863,13 +863,19 @@ static int vdi_resize(int argc, char **argv)
 	if (ret != EXIT_SUCCESS)
 		return ret;
 
-	if (new_size > SD_OLD_MAX_VDI_SIZE && 0 == inode->store_policy) {
-		sd_err("New VDI size is too large");
-		return EXIT_USAGE;
-	}
-
-	if (new_size > SD_MAX_VDI_SIZE) {
-		sd_err("New VDI size is too large");
+	object_size = (UINT32_C(1) << inode->block_size_shift);
+	old_max_total_size = object_size * OLD_MAX_DATA_OBJS;
+	if (0 == inode->store_policy) {
+		if (new_size > old_max_total_size) {
+			sd_err("New VDI size is too large."
+			       " This volume's max size is %"PRIu64,
+			       old_max_total_size);
+			return EXIT_USAGE;
+		}
+	} else if (new_size > SD_MAX_VDI_SIZE) {
+		sd_err("New VDI size is too large"
+			" This volume's max size is %llu",
+			SD_MAX_VDI_SIZE);
 		return EXIT_USAGE;
 	}
 
-- 
1.7.1