ext4: add ext4_es_store_pblock_status()

Avoid false positives by static code analysis tools such as sparse and
coverity caused by the fact that we set the physical block, and then
the status in the extent_status structure.  It is also more efficient
to set both of these values at once.

Addresses-Coverity-Id: #989077
Addresses-Coverity-Id: #989078
Addresses-Coverity-Id: #1080722

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>

2 files changed, 15 insertions, 8 deletions

diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 3981ff783950..a900004a63e1 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -658,8 +658,7 @@ int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
 
         newes.es_lblk = lblk;
         newes.es_len = len;
-        ext4_es_store_pblock(&newes, pblk);
-        ext4_es_store_status(&newes, status);
+        ext4_es_store_pblock_status(&newes, pblk, status);
         trace_ext4_es_insert_extent(inode, &newes);
 
         ext4_es_insert_extent_check(inode, &newes);
@@ -699,8 +698,7 @@ void ext4_es_cache_extent(struct inode *inode, ext4_lblk_t lblk,
 
         newes.es_lblk = lblk;
         newes.es_len = len;
-        ext4_es_store_pblock(&newes, pblk);
-        ext4_es_store_status(&newes, status);
+        ext4_es_store_pblock_status(&newes, pblk, status);
         trace_ext4_es_cache_extent(inode, &newes);
 
         if (!len)
@@ -812,13 +810,13 @@ retry:
 
                         newes.es_lblk = end + 1;
                         newes.es_len = len2;
+                        block = 0x7FDEADBEEF;
                         if (ext4_es_is_written(&orig_es) ||
-                            ext4_es_is_unwritten(&orig_es)) {
+                            ext4_es_is_unwritten(&orig_es))
                                 block = ext4_es_pblock(&orig_es) +
                                         orig_es.es_len - len2;
-                                ext4_es_store_pblock(&newes, block);
-                        }
-                        ext4_es_store_status(&newes, ext4_es_status(&orig_es));
+                        ext4_es_store_pblock_status(&newes, block,
+                                                    ext4_es_status(&orig_es));
                         err = __es_insert_extent(inode, &newes);
                         if (err) {
                                 es->es_lblk = orig_es.es_lblk;
diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h
index 167f4ab8ecc3..f1b62a419920 100644
--- a/fs/ext4/extents_status.h
+++ b/fs/ext4/extents_status.h
@@ -129,6 +129,15 @@ static inline void ext4_es_store_status(struct extent_status *es,
                        (es->es_pblk & ~ES_MASK));
 }
 
+static inline void ext4_es_store_pblock_status(struct extent_status *es,
+                                               ext4_fsblk_t pb,
+                                               unsigned int status)
+{
+        es->es_pblk = (((ext4_fsblk_t)
+                        (status & EXTENT_STATUS_FLAGS) << ES_SHIFT) |
+                       (pb & ~ES_MASK));
+}
+
 extern void ext4_es_register_shrinker(struct ext4_sb_info *sbi);
 extern void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi);
 extern void ext4_es_lru_add(struct inode *inode);