示例#1
0
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;

	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 (!bch_bkey_equal_header(k, 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;

			bch_subtract_dirty(k, c, 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);
			}
		}

		bch_subtract_dirty(k, c, 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;
}
示例#2
0
static uint64_t merge_chksums(struct bkey *l, struct bkey *r)
{
	return (l->ptr[KEY_PTRS(l)] + r->ptr[KEY_PTRS(r)]) &
		~((uint64_t)1 << 63);
}
示例#3
0
	return dc->verify;
}

static void bio_csum(struct bio *bio, struct bkey *k)
{
	struct bio_vec bv;
	struct bvec_iter iter;
	uint64_t csum = 0;

	bio_for_each_segment(bv, bio, iter) {
		void *d = kmap(bv.bv_page) + bv.bv_offset;
		csum = bch_crc64_update(csum, d, bv.bv_len);
		kunmap(bv.bv_page);
	}

	k->ptr[KEY_PTRS(k)] = csum & (~0ULL >> 1);
}

/* Insert data into cache */

static void bch_data_insert_keys(struct closure *cl)
{
	struct data_insert_op *op = container_of(cl, struct data_insert_op, cl);
	atomic_t *journal_ref = NULL;
	struct bkey *replace_key = op->replace ? &op->replace_key : NULL;
	int ret;

	/*
	 * If we're looping, might already be waiting on
	 * another journal write - can't wait on more than one journal write at
	 * a time