block: add blk_rq_set_block_pc()
With the optimizations around not clearing the full request at alloc
time, we are leaving some of the needed init for REQ_TYPE_BLOCK_PC
up to the user allocating the request.
Add a blk_rq_set_block_pc() that sets the command type to
REQ_TYPE_BLOCK_PC, and properly initializes the members associated
with this type of request. Update callers to use this function instead
of manipulating rq->cmd_type directly.
Includes fixes from Christoph Hellwig <hch@lst.de> for my half-assed
attempt.
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index 40d6548..9aca8c7 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1218,6 +1218,8 @@
if (unlikely(!rq))
return ERR_PTR(-ENOMEM);
+ blk_rq_set_block_pc(rq);
+
for_each_bio(bio) {
struct bio *bounce_bio = bio;
int ret;
@@ -1235,6 +1237,22 @@
EXPORT_SYMBOL(blk_make_request);
/**
+ * blk_rq_set_block_pc - initialize a requeest to type BLOCK_PC
+ * @rq: request to be initialized
+ *
+ */
+void blk_rq_set_block_pc(struct request *rq)
+{
+ rq->cmd_type = REQ_TYPE_BLOCK_PC;
+ rq->__data_len = 0;
+ rq->__sector = (sector_t) -1;
+ rq->bio = rq->biotail = NULL;
+ memset(rq->__cmd, 0, sizeof(rq->__cmd));
+ rq->cmd = rq->__cmd;
+}
+EXPORT_SYMBOL(blk_rq_set_block_pc);
+
+/**
* blk_requeue_request - put a request back on queue
* @q: request queue where request should be inserted
* @rq: request to be inserted