[f2fs-dev] [PATCH v2 4/7] f2fs-tools: Refactor SIT/NAT block structs

[Daniel Rosenberg via Linux-f2fs-devel <linux-f2fs-devel@lists.sourceforge.net>]

This converts f2fs_nat_block and f2fs_sit_block to be variable length
arrays. This does not change the way they are accessed, but removes a
misleading statment that these sizes are fixed, as opposed to deriving
from F2FS_BLKSIZE

Signed-off-by: Daniel Rosenberg <drosen@google.com>
---
 include/f2fs_fs.h | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
index 13a1c14..b2d479f 100644
--- a/include/f2fs_fs.h
+++ b/include/f2fs_fs.h
@@ -1119,11 +1119,9 @@ struct f2fs_nat_entry {
 static_assert(sizeof(struct f2fs_nat_entry) == 9, "");
 
 struct f2fs_nat_block {
-	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
+	struct f2fs_nat_entry entries[0]; /* NAT_ENTRY_PER_BLOCK */
 };
 
-static_assert(sizeof(struct f2fs_nat_block) == F2FS_BLKSIZE - (F2FS_BLKSIZE % 9), "");
-
 /*
  * For SIT entries
  *
@@ -1169,12 +1167,14 @@ struct f2fs_sit_entry {
 
 static_assert(sizeof(struct f2fs_sit_entry) == 74, "");
 
+/*
+ * On disk layout is:
+ * struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
+ */
 struct f2fs_sit_block {
-	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
+	struct f2fs_sit_entry entries[0];
 };
 
-static_assert(sizeof(struct f2fs_sit_block) == F2FS_BLKSIZE - (F2FS_BLKSIZE % 74), "");
-
 /*
  * For segment summary
  *
@@ -1995,6 +1995,14 @@ static inline void check_block_struct_sizes(void)
 
 	/* Check Indirect Block Size */
 	assert(NIDS_PER_BLOCK * sizeof(__le32) + sizeof(struct node_footer) == F2FS_BLKSIZE);
+
+	/* Check NAT Block Size */
+	assert((NAT_ENTRY_PER_BLOCK + 1) * sizeof(struct f2fs_nat_entry) > F2FS_BLKSIZE);
+	assert(NAT_ENTRY_PER_BLOCK * sizeof(struct f2fs_nat_entry) <= F2FS_BLKSIZE);
+
+	/* Check SIT Block Size */
+	assert((SIT_ENTRY_PER_BLOCK + 1) * sizeof(struct f2fs_nat_entry) > F2FS_BLKSIZE);
+	assert(SIT_ENTRY_PER_BLOCK * sizeof(struct f2fs_sit_entry) <= F2FS_BLKSIZE);
 }
 
 #endif	/*__F2FS_FS_H */
-- 
2.42.0.rc2.253.gd59a3bf2b4-goog



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel