bcache: Add bch_bkey_equal_header()

Checks if two keys have equivalent header fields.
(good enough for replacement or merging)

Used in bch_bkey_try_merge, and replacing a key
in the btree.

Signed-off-by: Nicholas Swenson <nks@daterainc.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>

3 files changed, 11 insertions, 8 deletions

diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
index 7f8a7bd21503..f990403c4f1c 100644
--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -788,12 +788,8 @@ bool bch_bkey_try_merge(struct btree_keys *b, struct bkey *l, struct bkey *r)
          * Assumes left and right are in order
          * Left and right must be exactly aligned
          */
-        if (KEY_U64s(l) != KEY_U64s(r) ||
-            KEY_DELETED(l) != KEY_DELETED(r) ||
-            KEY_CACHED(l) != KEY_CACHED(r) ||
-            KEY_VERSION(l) != KEY_VERSION(r) ||
-            KEY_CSUM(l) != KEY_CSUM(r) ||
-            bkey_cmp(l, &START_KEY(r)))
+        if (!bch_bkey_equal_header(l, r) ||
+             bkey_cmp(l, &START_KEY(r)))
                 return false;
 
         return b->ops->key_merge(b, l, r);
diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h
index 487373057c09..003260f4ddf6 100644
--- a/drivers/md/bcache/bset.h
+++ b/drivers/md/bcache/bset.h
@@ -448,6 +448,14 @@ static inline void bch_bkey_to_text(struct btree_keys *b, char *buf,
         return b->ops->key_to_text(buf, size, k);
 }
 
+static inline bool bch_bkey_equal_header(const struct bkey *l,
+                                         const struct bkey *r)
+{
+        return (KEY_DIRTY(l) == KEY_DIRTY(r) &&
+                KEY_PTRS(l) == KEY_PTRS(r) &&
+                KEY_CSUM(l) == KEY_CSUM(l));
+}
+
 /* Keylists */
 
 struct keylist {
diff --git a/drivers/md/bcache/extents.c b/drivers/md/bcache/extents.c
index 7d73d8625522..c3ead586dc27 100644
--- a/drivers/md/bcache/extents.c
+++ b/drivers/md/bcache/extents.c
@@ -372,8 +372,7 @@ static bool bch_extent_insert_fixup(struct btree_keys *b,
                         if (KEY_START(k) > KEY_START(insert) + sectors_found)
                                 goto check_failed;
 
-                        if (KEY_PTRS(k) != KEY_PTRS(replace_key) ||
-                            KEY_DIRTY(k) != KEY_DIRTY(replace_key))
+                        if (!bch_bkey_equal_header(k, replace_key))
                                 goto check_failed;
 
                         /* skip past gen */