From: Kent Overstreet <kmo@daterainc.com>
Date: Thu, 25 Jul 2013 00:24:25 +0000 (-0700)
Subject: bcache: Clean up keylist code
X-Git-Tag: next-20130912~34^2~6^2~40
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=65284ec60e4193e7b3efc335a24c87236180da0a;p=karo-tx-linux.git

bcache: Clean up keylist code

More random refactoring.

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

diff --git a/drivers/md/bcache/bset.c b/drivers/md/bcache/bset.c
index 75f9a2f9b391..1e7d946485ae 100644
--- a/drivers/md/bcache/bset.c
+++ b/drivers/md/bcache/bset.c
@@ -14,22 +14,12 @@
 
 /* Keylists */
 
-void bch_keylist_copy(struct keylist *dest, struct keylist *src)
-{
-	*dest = *src;
-
-	if (src->list == src->d) {
-		size_t n = (uint64_t *) src->top - src->d;
-		dest->top = (struct bkey *) &dest->d[n];
-		dest->list = dest->d;
-	}
-}
-
 int bch_keylist_realloc(struct keylist *l, int nptrs, struct cache_set *c)
 {
-	unsigned oldsize = (uint64_t *) l->top - l->list;
-	unsigned newsize = oldsize + 2 + nptrs;
-	uint64_t *new;
+	size_t oldsize = bch_keylist_nkeys(l);
+	size_t newsize = oldsize + 2 + nptrs;
+	uint64_t *old_keys = l->keys_p == l->inline_keys ? NULL : l->keys_p;
+	uint64_t *new_keys;
 
 	/* The journalling code doesn't handle the case where the keys to insert
 	 * is bigger than an empty write: If we just return -ENOMEM here,
@@ -45,24 +35,23 @@ int bch_keylist_realloc(struct keylist *l, int nptrs, struct cache_set *c)
 	    roundup_pow_of_two(oldsize) == newsize)
 		return 0;
 
-	new = krealloc(l->list == l->d ? NULL : l->list,
-		       sizeof(uint64_t) * newsize, GFP_NOIO);
+	new_keys = krealloc(old_keys, sizeof(uint64_t) * newsize, GFP_NOIO);
 
-	if (!new)
+	if (!new_keys)
 		return -ENOMEM;
 
-	if (l->list == l->d)
-		memcpy(new, l->list, sizeof(uint64_t) * KEYLIST_INLINE);
+	if (!old_keys)
+		memcpy(new_keys, l->inline_keys, sizeof(uint64_t) * oldsize);
 
-	l->list = new;
-	l->top = (struct bkey *) (&l->list[oldsize]);
+	l->keys_p = new_keys;
+	l->top_p = new_keys + oldsize;
 
 	return 0;
 }
 
 struct bkey *bch_keylist_pop(struct keylist *l)
 {
-	struct bkey *k = l->bottom;
+	struct bkey *k = l->keys;
 
 	if (k == l->top)
 		return NULL;
@@ -75,14 +64,11 @@ struct bkey *bch_keylist_pop(struct keylist *l)
 
 void bch_keylist_pop_front(struct keylist *l)
 {
-	struct bkey *next = bkey_next(l->bottom);
-	size_t bytes = ((void *) l->top) - ((void *) next);
-
-	memmove(l->bottom,
-		next,
-		bytes);
+	l->top_p -= bkey_u64s(l->keys);
 
-	l->top = ((void *) l->bottom) + bytes;
+	memmove(l->keys,
+		bkey_next(l->keys),
+		bch_keylist_bytes(l));
 }
 
 /* Pointer validation */
diff --git a/drivers/md/bcache/bset.h b/drivers/md/bcache/bset.h
index a3627d0cd88b..8a9305685b7e 100644
--- a/drivers/md/bcache/bset.h
+++ b/drivers/md/bcache/bset.h
@@ -227,20 +227,23 @@ static inline struct bkey *bkey_next(const struct bkey *k)
 /* Keylists */
 
 struct keylist {
-	struct bkey		*top;
 	union {
-		uint64_t		*list;
-		struct bkey		*bottom;
+		struct bkey		*keys;
+		uint64_t		*keys_p;
+	};
+	union {
+		struct bkey		*top;
+		uint64_t		*top_p;
 	};
 
 	/* Enough room for btree_split's keys without realloc */
 #define KEYLIST_INLINE		16
-	uint64_t		d[KEYLIST_INLINE];
+	uint64_t		inline_keys[KEYLIST_INLINE];
 };
 
 static inline void bch_keylist_init(struct keylist *l)
 {
-	l->top = (void *) (l->list = l->d);
+	l->top_p = l->keys_p = l->inline_keys;
 }
 
 static inline void bch_keylist_push(struct keylist *l)
@@ -256,16 +259,30 @@ static inline void bch_keylist_add(struct keylist *l, struct bkey *k)
 
 static inline bool bch_keylist_empty(struct keylist *l)
 {
-	return l->top == (void *) l->list;
+	return l->top == l->keys;
+}
+
+static inline void bch_keylist_reset(struct keylist *l)
+{
+	l->top = l->keys;
 }
 
 static inline void bch_keylist_free(struct keylist *l)
 {
-	if (l->list != l->d)
-		kfree(l->list);
+	if (l->keys_p != l->inline_keys)
+		kfree(l->keys_p);
+}
+
+static inline size_t bch_keylist_nkeys(struct keylist *l)
+{
+	return l->top_p - l->keys_p;
+}
+
+static inline size_t bch_keylist_bytes(struct keylist *l)
+{
+	return bch_keylist_nkeys(l) * sizeof(uint64_t);
 }
 
-void bch_keylist_copy(struct keylist *, struct keylist *);
 struct bkey *bch_keylist_pop(struct keylist *);
 void bch_keylist_pop_front(struct keylist *);
 int bch_keylist_realloc(struct keylist *, int, struct cache_set *);
diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c
index 6ef188e30f41..c1a1af72f043 100644
--- a/drivers/md/bcache/btree.c
+++ b/drivers/md/bcache/btree.c
@@ -1854,7 +1854,7 @@ static bool bch_btree_insert_keys(struct btree *b, struct btree_op *op,
 
 	while (!bch_keylist_empty(insert_keys)) {
 		struct bset *i = write_block(b);
-		struct bkey *k = insert_keys->bottom;
+		struct bkey *k = insert_keys->keys;
 
 		if (b->written + __set_blocks(i, i->keys + bkey_u64s(k), b->c)
 		    > btree_blocks(b))
@@ -1875,10 +1875,10 @@ static bool bch_btree_insert_keys(struct btree *b, struct btree_op *op,
 			}
 #endif
 			BKEY_PADDED(key) temp;
-			bkey_copy(&temp.key, insert_keys->bottom);
+			bkey_copy(&temp.key, insert_keys->keys);
 
 			bch_cut_back(&b->key, &temp.key);
-			bch_cut_front(&b->key, insert_keys->bottom);
+			bch_cut_front(&b->key, insert_keys->keys);
 
 			ret |= btree_insert_key(b, op, &temp.key);
 			break;
@@ -1972,7 +1972,7 @@ static int btree_split(struct btree *b, struct btree_op *op,
 	} else if (!b->parent) {
 		/* Root filled up but didn't need to be split */
 
-		parent_keys->top = parent_keys->bottom;
+		bch_keylist_reset(parent_keys);
 		closure_sync(&op->cl);
 		bch_btree_set_root(n1);
 	} else {
@@ -2106,12 +2106,12 @@ static int bch_btree_insert_recurse(struct btree *b, struct btree_op *op,
 	if (b->level) {
 		struct bkey *k;
 
-		k = bch_next_recurse_key(b, &START_KEY(keys->bottom));
+		k = bch_next_recurse_key(b, &START_KEY(keys->keys));
 		if (!k) {
 			btree_bug(b, "no key to recurse on at level %i/%i",
 				  b->level, b->c->root->level);
 
-			keys->top = keys->bottom;
+			bch_keylist_reset(keys);
 			return -EIO;
 		}
 
diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c
index ea79d305f154..a08a147dcfe8 100644
--- a/drivers/md/bcache/journal.c
+++ b/drivers/md/bcache/journal.c
@@ -710,7 +710,7 @@ void bch_journal(struct closure *cl)
 	struct btree_op *op = container_of(cl, struct btree_op, cl);
 	struct cache_set *c = op->c;
 	struct journal_write *w;
-	size_t b, n = ((uint64_t *) op->keys.top) - op->keys.list;
+	size_t sectors, nkeys;
 
 	if (op->type != BTREE_INSERT ||
 	    !CACHE_SYNC(&c->sb))
@@ -739,10 +739,12 @@ void bch_journal(struct closure *cl)
 
 	w = c->journal.cur;
 	w->need_write = true;
-	b = __set_blocks(w->data, w->data->keys + n, c);
+	nkeys = w->data->keys + bch_keylist_nkeys(&op->keys);
+	sectors = __set_blocks(w->data, nkeys, c) * c->sb.block_size;
 
-	if (b * c->sb.block_size > PAGE_SECTORS << JSET_BITS ||
-	    b > c->journal.blocks_free) {
+	if (sectors > min_t(size_t,
+			    c->journal.blocks_free * c->sb.block_size,
+			    PAGE_SECTORS << JSET_BITS)) {
 		trace_bcache_journal_entry_full(c);
 
 		/*
@@ -760,8 +762,8 @@ void bch_journal(struct closure *cl)
 		continue_at(cl, bch_journal, bcache_wq);
 	}
 
-	memcpy(end(w->data), op->keys.list, n * sizeof(uint64_t));
-	w->data->keys += n;
+	memcpy(end(w->data), op->keys.keys, bch_keylist_bytes(&op->keys));
+	w->data->keys += bch_keylist_nkeys(&op->keys);
 
 	op->journal = &fifo_back(&c->journal.pin);
 	atomic_inc(op->journal);
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 91cd28cd56bd..57e41cd8144e 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -438,13 +438,13 @@ static void bch_insert_data_error(struct closure *cl)
 	 * from the keys we'll accomplish just that.
 	 */
 
-	struct bkey *src = op->keys.bottom, *dst = op->keys.bottom;
+	struct bkey *src = op->keys.keys, *dst = op->keys.keys;
 
 	while (src != op->keys.top) {
 		struct bkey *n = bkey_next(src);
 
 		SET_KEY_PTRS(src, 0);
-		bkey_copy(dst, src);
+		memmove(dst, src, bkey_bytes(src));
 
 		dst = bkey_next(dst);
 		src = n;