bcache: Move insert_fixup() to btree_keys_ops

Now handling overlapping extents/keys is a method that's specific to what the
btree node contains.

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

4 files changed, 257 insertions, 229 deletions

diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
index 2ff75f3..4a71132 100644
--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -676,6 +676,8 @@ void bch_bset_build_written_tree(struct btree_keys *b)
 }
 EXPORT_SYMBOL(bch_bset_build_written_tree);
 
+/* Insert */
+
 void bch_bset_fix_invalidated_key(struct btree_keys *b, struct bkey *k)
 {
 	struct bset_tree *t;
@@ -791,6 +793,54 @@ void bch_bset_insert(struct btree_keys *b, struct bkey *where,
 }
 EXPORT_SYMBOL(bch_bset_insert);
 
+unsigned bch_btree_insert_key(struct btree_keys *b, struct bkey *k,
+			      struct bkey *replace_key)
+{
+	unsigned status = BTREE_INSERT_STATUS_NO_INSERT;
+	struct bset *i = bset_tree_last(b)->data;
+	struct bkey *m, *prev = NULL;
+	struct btree_iter iter;
+
+	BUG_ON(b->ops->is_extents && !KEY_SIZE(k));
+
+	m = bch_btree_iter_init(b, &iter, b->ops->is_extents
+				? PRECEDING_KEY(&START_KEY(k))
+				: PRECEDING_KEY(k));
+
+	if (b->ops->insert_fixup(b, k, &iter, replace_key))
+		return status;
+
+	status = BTREE_INSERT_STATUS_INSERT;
+
+	while (m != bset_bkey_last(i) &&
+	       bkey_cmp(k, b->ops->is_extents ? &START_KEY(m) : m) > 0)
+		prev = m, m = bkey_next(m);
+
+	/* prev is in the tree, if we merge we're done */
+	status = BTREE_INSERT_STATUS_BACK_MERGE;
+	if (prev &&
+	    bch_bkey_try_merge(b, prev, k))
+		goto merged;
+#if 0
+	status = BTREE_INSERT_STATUS_OVERWROTE;
+	if (m != bset_bkey_last(i) &&
+	    KEY_PTRS(m) == KEY_PTRS(k) && !KEY_SIZE(m))
+		goto copy;
+#endif
+	status = BTREE_INSERT_STATUS_FRONT_MERGE;
+	if (m != bset_bkey_last(i) &&
+	    bch_bkey_try_merge(b, k, m))
+		goto copy;
+
+	bch_bset_insert(b, m, k);
+copy:	bkey_copy(m, k);
+merged:
+	return status;
+}
+EXPORT_SYMBOL(bch_btree_insert_key);
+
+/* Lookup */
+
 struct bset_search_iter {
 	struct bkey *l, *r;
 };
diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h
index 4aa199d..759df83 100644
--- a/drivers/md/bcache/bset.h
+++ b/drivers/md/bcache/bset.h
@@ -189,6 +189,8 @@ struct btree_keys_ops {
 	bool		(*sort_cmp)(struct btree_iter_set,
 				    struct btree_iter_set);
 	struct bkey	*(*sort_fixup)(struct btree_iter *, struct bkey *);
+	bool		(*insert_fixup)(struct btree_keys *, struct bkey *,
+					struct btree_iter *, struct bkey *);
 	bool		(*key_invalid)(struct btree_keys *,
 				       const struct bkey *);
 	bool		(*key_bad)(struct btree_keys *, const struct bkey *);
@@ -286,6 +288,16 @@ void bch_bset_init_next(struct btree_keys *, struct bset *, uint64_t);
 void bch_bset_build_written_tree(struct btree_keys *);
 void bch_bset_fix_invalidated_key(struct btree_keys *, struct bkey *);
 void bch_bset_insert(struct btree_keys *, struct bkey *, struct bkey *);
+unsigned bch_btree_insert_key(struct btree_keys *, struct bkey *,
+			      struct bkey *);
+
+enum {
+	BTREE_INSERT_STATUS_NO_INSERT = 0,
+	BTREE_INSERT_STATUS_INSERT,
+	BTREE_INSERT_STATUS_BACK_MERGE,
+	BTREE_INSERT_STATUS_OVERWROTE,
+	BTREE_INSERT_STATUS_FRONT_MERGE,
+};
 
 /*
  * Tries to merge l and r: l should be lower than r
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index b14f34a..463d280 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -24,7 +24,6 @@
 #include "btree.h"
 #include "debug.h"
 #include "extents.h"
-#include "writeback.h"
 
 #include <linux/slab.h>
 #include <linux/bitops.h>
@@ -90,13 +89,6 @@
  * Test module load/unload
  */
 
-enum {
-	BTREE_INSERT_STATUS_INSERT,
-	BTREE_INSERT_STATUS_BACK_MERGE,
-	BTREE_INSERT_STATUS_OVERWROTE,
-	BTREE_INSERT_STATUS_FRONT_MERGE,
-};
-
 #define MAX_NEED_GC		64
 #define MAX_SAVE_PRIO		72
 
@@ -1792,230 +1784,23 @@ err:
 
 /* Btree insertion */
 
-static bool fix_overlapping_extents(struct btree *b, struct bkey *insert,
-				    struct btree_iter *iter,
-				    struct bkey *replace_key)
+static bool btree_insert_key(struct btree *b, struct bkey *k,
+			     struct bkey *replace_key)
 {
-	void subtract_dirty(struct bkey *k, uint64_t offset, int sectors)
-	{
-		if (KEY_DIRTY(k))
-			bcache_dev_sectors_dirty_add(b->c, KEY_INODE(k),
-						     offset, -sectors);
-	}
-
-	uint64_t old_offset;
-	unsigned old_size, sectors_found = 0;
-
-	while (1) {
-		struct bkey *k = bch_btree_iter_next(iter);
-		if (!k)
-			break;
-
-		if (bkey_cmp(&START_KEY(k), insert) >= 0) {
-			if (KEY_SIZE(k))
-				break;
-			else
-				continue;
-		}
-
-		if (bkey_cmp(k, &START_KEY(insert)) <= 0)
-			continue;
-
-		old_offset = KEY_START(k);
-		old_size = KEY_SIZE(k);
-
-		/*
-		 * We might overlap with 0 size extents; we can't skip these
-		 * because if they're in the set we're inserting to we have to
-		 * adjust them so they don't overlap with the key we're
-		 * inserting. But we don't want to check them for replace
-		 * operations.
-		 */
-
-		if (replace_key && KEY_SIZE(k)) {
-			/*
-			 * k might have been split since we inserted/found the
-			 * key we're replacing
-			 */
-			unsigned i;
-			uint64_t offset = KEY_START(k) -
-				KEY_START(replace_key);
-
-			/* But it must be a subset of the replace key */
-			if (KEY_START(k) < KEY_START(replace_key) ||
-			    KEY_OFFSET(k) > KEY_OFFSET(replace_key))
-				goto check_failed;
-
-			/* We didn't find a key that we were supposed to */
-			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))
-				goto check_failed;
-
-			/* skip past gen */
-			offset <<= 8;
-
-			BUG_ON(!KEY_PTRS(replace_key));
-
-			for (i = 0; i < KEY_PTRS(replace_key); i++)
-				if (k->ptr[i] != replace_key->ptr[i] + offset)
-					goto check_failed;
-
-			sectors_found = KEY_OFFSET(k) - KEY_START(insert);
-		}
-
-		if (bkey_cmp(insert, k) < 0 &&
-		    bkey_cmp(&START_KEY(insert), &START_KEY(k)) > 0) {
-			/*
-			 * We overlapped in the middle of an existing key: that
-			 * means we have to split the old key. But we have to do
-			 * slightly different things depending on whether the
-			 * old key has been written out yet.
-			 */
-
-			struct bkey *top;
-
-			subtract_dirty(k, KEY_START(insert), KEY_SIZE(insert));
-
-			if (bkey_written(&b->keys, k)) {
-				/*
-				 * We insert a new key to cover the top of the
-				 * old key, and the old key is modified in place
-				 * to represent the bottom split.
-				 *
-				 * It's completely arbitrary whether the new key
-				 * is the top or the bottom, but it has to match
-				 * up with what btree_sort_fixup() does - it
-				 * doesn't check for this kind of overlap, it
-				 * depends on us inserting a new key for the top
-				 * here.
-				 */
-				top = bch_bset_search(&b->keys,
-						      bset_tree_last(&b->keys),
-						      insert);
-				bch_bset_insert(&b->keys, top, k);
-			} else {
-				BKEY_PADDED(key) temp;
-				bkey_copy(&temp.key, k);
-				bch_bset_insert(&b->keys, k, &temp.key);
-				top = bkey_next(k);
-			}
-
-			bch_cut_front(insert, top);
-			bch_cut_back(&START_KEY(insert), k);
-			bch_bset_fix_invalidated_key(&b->keys, k);
-			return false;
-		}
-
-		if (bkey_cmp(insert, k) < 0) {
-			bch_cut_front(insert, k);
-		} else {
-			if (bkey_cmp(&START_KEY(insert), &START_KEY(k)) > 0)
-				old_offset = KEY_START(insert);
-
-			if (bkey_written(&b->keys, k) &&
-			    bkey_cmp(&START_KEY(insert), &START_KEY(k)) <= 0) {
-				/*
-				 * Completely overwrote, so we don't have to
-				 * invalidate the binary search tree
-				 */
-				bch_cut_front(k, k);
-			} else {
-				__bch_cut_back(&START_KEY(insert), k);
-				bch_bset_fix_invalidated_key(&b->keys, k);
-			}
-		}
-
-		subtract_dirty(k, old_offset, old_size - KEY_SIZE(k));
-	}
-
-check_failed:
-	if (replace_key) {
-		if (!sectors_found) {
-			return true;
-		} else if (sectors_found < KEY_SIZE(insert)) {
-			SET_KEY_OFFSET(insert, KEY_OFFSET(insert) -
-				       (KEY_SIZE(insert) - sectors_found));
-			SET_KEY_SIZE(insert, sectors_found);
-		}
-	}
-
-	return false;
-}
-
-static bool btree_insert_key(struct btree *b, struct btree_op *op,
-			     struct bkey *k, struct bkey *replace_key)
-{
-	struct bset *i = btree_bset_last(b);
-	struct bkey *m, *prev;
-	unsigned status = BTREE_INSERT_STATUS_INSERT;
+	unsigned status;
 
 	BUG_ON(bkey_cmp(k, &b->key) > 0);
-	BUG_ON(b->level && !KEY_PTRS(k));
-	BUG_ON(!b->level && !KEY_OFFSET(k));
 
-	if (!b->level) {
-		struct btree_iter iter;
+	status = bch_btree_insert_key(&b->keys, k, replace_key);
+	if (status != BTREE_INSERT_STATUS_NO_INSERT) {
+		bch_check_keys(&b->keys, "%u for %s", status,
+			       replace_key ? "replace" : "insert");
 
-		/*
-		 * bset_search() returns the first key that is strictly greater
-		 * than the search key - but for back merging, we want to find
-		 * the previous key.
-		 */
-		prev = NULL;
-		m = bch_btree_iter_init(&b->keys, &iter,
-					PRECEDING_KEY(&START_KEY(k)));
-
-		if (fix_overlapping_extents(b, k, &iter, replace_key)) {
-			op->insert_collision = true;
-			return false;
-		}
-
-		if (KEY_DIRTY(k))
-			bcache_dev_sectors_dirty_add(b->c, KEY_INODE(k),
-						     KEY_START(k), KEY_SIZE(k));
-
-		while (m != bset_bkey_last(i) &&
-		       bkey_cmp(k, &START_KEY(m)) > 0)
-			prev = m, m = bkey_next(m);
-
-		if (key_merging_disabled(b->c))
-			goto insert;
-
-		/* prev is in the tree, if we merge we're done */
-		status = BTREE_INSERT_STATUS_BACK_MERGE;
-		if (prev &&
-		    bch_bkey_try_merge(&b->keys, prev, k))
-			goto merged;
-
-		status = BTREE_INSERT_STATUS_OVERWROTE;
-		if (m != bset_bkey_last(i) &&
-		    KEY_PTRS(m) == KEY_PTRS(k) && !KEY_SIZE(m))
-			goto copy;
-
-		status = BTREE_INSERT_STATUS_FRONT_MERGE;
-		if (m != bset_bkey_last(i) &&
-		    bch_bkey_try_merge(&b->keys, k, m))
-			goto copy;
-	} else {
-		BUG_ON(replace_key);
-		m = bch_bset_search(&b->keys, bset_tree_last(&b->keys), k);
-	}
-
-insert:	bch_bset_insert(&b->keys, m, k);
-copy:	bkey_copy(m, k);
-merged:
-	bch_check_keys(&b->keys, "%u for %s", status,
-		       replace_key ? "replace" : "insert");
-
-	if (b->level && !KEY_OFFSET(k))
-		btree_current_write(b)->prio_blocked++;
-
-	trace_bcache_btree_insert_key(b, k, replace_key != NULL, status);
-
-	return true;
+		trace_bcache_btree_insert_key(b, k, replace_key != NULL,
+					      status);
+		return true;
+	} else
+		return false;
 }
 
 static size_t insert_u64s_remaining(struct btree *b)
@@ -2048,7 +1833,7 @@ static bool bch_btree_insert_keys(struct btree *b, struct btree_op *op,
 			if (!b->level)
 				bkey_put(b->c, k);
 
-			ret |= btree_insert_key(b, op, k, replace_key);
+			ret |= btree_insert_key(b, k, replace_key);
 			bch_keylist_pop_front(insert_keys);
 		} else if (bkey_cmp(&START_KEY(k), &b->key) < 0) {
 			BKEY_PADDED(key) temp;
@@ -2057,13 +1842,16 @@ static bool bch_btree_insert_keys(struct btree *b, struct btree_op *op,
 			bch_cut_back(&b->key, &temp.key);
 			bch_cut_front(&b->key, insert_keys->keys);
 
-			ret |= btree_insert_key(b, op, &temp.key, replace_key);
+			ret |= btree_insert_key(b, &temp.key, replace_key);
 			break;
 		} else {
 			break;
 		}
 	}
 
+	if (!ret)
+		op->insert_collision = true;
+
 	BUG_ON(!bch_keylist_empty(insert_keys) && b->level);
 
 	BUG_ON(bch_count_data(&b->keys) < oldsize);
diff --git a/drivers/md/bcache/extents.c b/drivers/md/bcache/extents.c
index bc1c3ee..d6de3c7 100644
--- a/drivers/md/bcache/extents.c
+++ b/drivers/md/bcache/extents.c
@@ -222,8 +222,22 @@ static bool bch_btree_ptr_bad(struct btree_keys *bk, const struct bkey *k)
 	return false;
 }
 
+static bool bch_btree_ptr_insert_fixup(struct btree_keys *bk,
+				       struct bkey *insert,
+				       struct btree_iter *iter,
+				       struct bkey *replace_key)
+{
+	struct btree *b = container_of(bk, struct btree, keys);
+
+	if (!KEY_OFFSET(insert))
+		btree_current_write(b)->prio_blocked++;
+
+	return false;
+}
+
 const struct btree_keys_ops bch_btree_keys_ops = {
 	.sort_cmp	= bch_key_sort_cmp,
+	.insert_fixup	= bch_btree_ptr_insert_fixup,
 	.key_invalid	= bch_btree_ptr_invalid,
 	.key_bad	= bch_btree_ptr_bad,
 	.key_to_text	= bch_extent_to_text,
@@ -294,6 +308,169 @@ static struct bkey *bch_extent_sort_fixup(struct btree_iter *iter,
 	return NULL;
 }
 
+static bool bch_extent_insert_fixup(struct btree_keys *b,
+				    struct bkey *insert,
+				    struct btree_iter *iter,
+				    struct bkey *replace_key)
+{
+	struct cache_set *c = container_of(b, struct btree, keys)->c;
+
+	void subtract_dirty(struct bkey *k, uint64_t offset, int sectors)
+	{
+		if (KEY_DIRTY(k))
+			bcache_dev_sectors_dirty_add(c, KEY_INODE(k),
+						     offset, -sectors);
+	}
+
+	uint64_t old_offset;
+	unsigned old_size, sectors_found = 0;
+
+	BUG_ON(!KEY_OFFSET(insert));
+	BUG_ON(!KEY_SIZE(insert));
+
+	while (1) {
+		struct bkey *k = bch_btree_iter_next(iter);
+		if (!k)
+			break;
+
+		if (bkey_cmp(&START_KEY(k), insert) >= 0) {
+			if (KEY_SIZE(k))
+				break;
+			else
+				continue;
+		}
+
+		if (bkey_cmp(k, &START_KEY(insert)) <= 0)
+			continue;
+
+		old_offset = KEY_START(k);
+		old_size = KEY_SIZE(k);
+
+		/*
+		 * We might overlap with 0 size extents; we can't skip these
+		 * because if they're in the set we're inserting to we have to
+		 * adjust them so they don't overlap with the key we're
+		 * inserting. But we don't want to check them for replace
+		 * operations.
+		 */
+
+		if (replace_key && KEY_SIZE(k)) {
+			/*
+			 * k might have been split since we inserted/found the
+			 * key we're replacing
+			 */
+			unsigned i;
+			uint64_t offset = KEY_START(k) -
+				KEY_START(replace_key);
+
+			/* But it must be a subset of the replace key */
+			if (KEY_START(k) < KEY_START(replace_key) ||
+			    KEY_OFFSET(k) > KEY_OFFSET(replace_key))
+				goto check_failed;
+
+			/* We didn't find a key that we were supposed to */
+			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))
+				goto check_failed;
+
+			/* skip past gen */
+			offset <<= 8;
+
+			BUG_ON(!KEY_PTRS(replace_key));
+
+			for (i = 0; i < KEY_PTRS(replace_key); i++)
+				if (k->ptr[i] != replace_key->ptr[i] + offset)
+					goto check_failed;
+
+			sectors_found = KEY_OFFSET(k) - KEY_START(insert);
+		}
+
+		if (bkey_cmp(insert, k) < 0 &&
+		    bkey_cmp(&START_KEY(insert), &START_KEY(k)) > 0) {
+			/*
+			 * We overlapped in the middle of an existing key: that
+			 * means we have to split the old key. But we have to do
+			 * slightly different things depending on whether the
+			 * old key has been written out yet.
+			 */
+
+			struct bkey *top;
+
+			subtract_dirty(k, KEY_START(insert), KEY_SIZE(insert));
+
+			if (bkey_written(b, k)) {
+				/*
+				 * We insert a new key to cover the top of the
+				 * old key, and the old key is modified in place
+				 * to represent the bottom split.
+				 *
+				 * It's completely arbitrary whether the new key
+				 * is the top or the bottom, but it has to match
+				 * up with what btree_sort_fixup() does - it
+				 * doesn't check for this kind of overlap, it
+				 * depends on us inserting a new key for the top
+				 * here.
+				 */
+				top = bch_bset_search(b, bset_tree_last(b),
+						      insert);
+				bch_bset_insert(b, top, k);
+			} else {
+				BKEY_PADDED(key) temp;
+				bkey_copy(&temp.key, k);
+				bch_bset_insert(b, k, &temp.key);
+				top = bkey_next(k);
+			}
+
+			bch_cut_front(insert, top);
+			bch_cut_back(&START_KEY(insert), k);
+			bch_bset_fix_invalidated_key(b, k);
+			goto out;
+		}
+
+		if (bkey_cmp(insert, k) < 0) {
+			bch_cut_front(insert, k);
+		} else {
+			if (bkey_cmp(&START_KEY(insert), &START_KEY(k)) > 0)
+				old_offset = KEY_START(insert);
+
+			if (bkey_written(b, k) &&
+			    bkey_cmp(&START_KEY(insert), &START_KEY(k)) <= 0) {
+				/*
+				 * Completely overwrote, so we don't have to
+				 * invalidate the binary search tree
+				 */
+				bch_cut_front(k, k);
+			} else {
+				__bch_cut_back(&START_KEY(insert), k);
+				bch_bset_fix_invalidated_key(b, k);
+			}
+		}
+
+		subtract_dirty(k, old_offset, old_size - KEY_SIZE(k));
+	}
+
+check_failed:
+	if (replace_key) {
+		if (!sectors_found) {
+			return true;
+		} else if (sectors_found < KEY_SIZE(insert)) {
+			SET_KEY_OFFSET(insert, KEY_OFFSET(insert) -
+				       (KEY_SIZE(insert) - sectors_found));
+			SET_KEY_SIZE(insert, sectors_found);
+		}
+	}
+out:
+	if (KEY_DIRTY(insert))
+		bcache_dev_sectors_dirty_add(c, KEY_INODE(insert),
+					     KEY_START(insert),
+					     KEY_SIZE(insert));
+
+	return false;
+}
+
 static bool bch_extent_invalid(struct btree_keys *bk, const struct bkey *k)
 {
 	struct btree *b = container_of(bk, struct btree, keys);
@@ -435,6 +612,7 @@ static bool bch_extent_merge(struct btree_keys *bk, struct bkey *l, struct bkey
 const struct btree_keys_ops bch_extent_keys_ops = {
 	.sort_cmp	= bch_extent_sort_cmp,
 	.sort_fixup	= bch_extent_sort_fixup,
+	.insert_fixup	= bch_extent_insert_fixup,
 	.key_invalid	= bch_extent_invalid,
 	.key_bad	= bch_extent_bad,
 	.key_merge	= bch_extent_merge,