summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJens Axboe <jens.axboe@oracle.com>2008-02-08 12:41:03 +0100
committerJens Axboe <jens.axboe@oracle.com>2008-02-08 12:41:03 +0100
commit63a7138671c50a6f2c27bbd1a308dc75967062a3 (patch)
tree6d8b0d9cbc05bce2848299b61528cabc6d04d267
parenta4ffc0a0b240a29cbe489f6db9dae112a49ef1c1 (diff)
block: fixup rq_init() a bit
Rearrange fields in cache order and initialize some fields that we didn't previously init. Remove init of ->completion_data, it's part of a union with ->hash. Luckily clearing the rb node is the same as setting it to null! Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
-rw-r--r--block/blk-core.c23
-rw-r--r--include/linux/blkdev.h4
2 files changed, 20 insertions, 7 deletions
diff --git a/block/blk-core.c b/block/blk-core.c
index 4afb39c82339..fba4ca7c6086 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -102,27 +102,38 @@ struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev)
}
EXPORT_SYMBOL(blk_get_backing_dev_info);
+/*
+ * We can't just memset() the structure, since the allocation path
+ * already stored some information in the request.
+ */
void rq_init(struct request_queue *q, struct request *rq)
{
INIT_LIST_HEAD(&rq->queuelist);
INIT_LIST_HEAD(&rq->donelist);
-
- rq->errors = 0;
+ rq->q = q;
+ rq->sector = rq->hard_sector = (sector_t) -1;
+ rq->nr_sectors = rq->hard_nr_sectors = 0;
+ rq->current_nr_sectors = rq->hard_cur_sectors = 0;
rq->bio = rq->biotail = NULL;
INIT_HLIST_NODE(&rq->hash);
RB_CLEAR_NODE(&rq->rb_node);
+ rq->rq_disk = NULL;
+ rq->nr_phys_segments = 0;
+ rq->nr_hw_segments = 0;
rq->ioprio = 0;
+ rq->special = NULL;
rq->buffer = NULL;
+ rq->tag = -1;
+ rq->errors = 0;
rq->ref_count = 1;
- rq->q = q;
- rq->special = NULL;
+ rq->cmd_len = 0;
+ memset(rq->cmd, 0, sizeof(rq->cmd));
rq->data_len = 0;
+ rq->sense_len = 0;
rq->data = NULL;
- rq->nr_phys_segments = 0;
rq->sense = NULL;
rq->end_io = NULL;
rq->end_io_data = NULL;
- rq->completion_data = NULL;
rq->next_rq = NULL;
}
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 90392a9d7a9c..e1888cc5b8ae 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -137,7 +137,9 @@ enum rq_flag_bits {
#define BLK_MAX_CDB 16
/*
- * try to put the fields that are referenced together in the same cacheline
+ * try to put the fields that are referenced together in the same cacheline.
+ * if you modify this structure, be sure to check block/blk-core.c:rq_init()
+ * as well!
*/
struct request {
struct list_head queuelist;