block: do not use REQ_FLUSH for tracking flush support

The last patch added a REQ_OP_FLUSH for request_fn drivers
and the next patch renames REQ_FLUSH to REQ_PREFLUSH which
will be used by file systems and make_request_fn drivers so
they can send a write/flush combo.

This patch drops xen's use of REQ_FLUSH to track if it supports
REQ_OP_FLUSH requests, so REQ_FLUSH can be deleted.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Juergen Gross <kernel@pfupf.net>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Mike Christie 2016-06-05 14:32:24 -05:00 committed by Jens Axboe
parent 3a5e02ced1
commit a418090aa8

View File

@ -196,6 +196,7 @@ struct blkfront_info
unsigned int nr_ring_pages;
struct request_queue *rq;
unsigned int feature_flush;
unsigned int feature_fua;
unsigned int feature_discard:1;
unsigned int feature_secdiscard:1;
unsigned int discard_granularity;
@ -763,19 +764,14 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
* implement it the same way. (It's also a FLUSH+FUA,
* since it is guaranteed ordered WRT previous writes.)
*/
switch (info->feature_flush &
((REQ_FLUSH|REQ_FUA))) {
case REQ_FLUSH|REQ_FUA:
if (info->feature_flush && info->feature_fua)
ring_req->operation =
BLKIF_OP_WRITE_BARRIER;
break;
case REQ_FLUSH:
else if (info->feature_flush)
ring_req->operation =
BLKIF_OP_FLUSH_DISKCACHE;
break;
default:
else
ring_req->operation = 0;
}
}
ring_req->u.rw.nr_segments = num_grant;
if (unlikely(require_extra_req)) {
@ -866,9 +862,9 @@ static inline bool blkif_request_flush_invalid(struct request *req,
{
return ((req->cmd_type != REQ_TYPE_FS) ||
((req_op(req) == REQ_OP_FLUSH) &&
!(info->feature_flush & REQ_FLUSH)) ||
!info->feature_flush) ||
((req->cmd_flags & REQ_FUA) &&
!(info->feature_flush & REQ_FUA)));
!info->feature_fua));
}
static int blkif_queue_rq(struct blk_mq_hw_ctx *hctx,
@ -985,24 +981,22 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size,
return 0;
}
static const char *flush_info(unsigned int feature_flush)
static const char *flush_info(struct blkfront_info *info)
{
switch (feature_flush & ((REQ_FLUSH | REQ_FUA))) {
case REQ_FLUSH|REQ_FUA:
if (info->feature_flush && info->feature_fua)
return "barrier: enabled;";
case REQ_FLUSH:
else if (info->feature_flush)
return "flush diskcache: enabled;";
default:
else
return "barrier or flush: disabled;";
}
}
static void xlvbd_flush(struct blkfront_info *info)
{
blk_queue_write_cache(info->rq, info->feature_flush & REQ_FLUSH,
info->feature_flush & REQ_FUA);
blk_queue_write_cache(info->rq, info->feature_flush ? true : false,
info->feature_fua ? true : false);
pr_info("blkfront: %s: %s %s %s %s %s\n",
info->gd->disk_name, flush_info(info->feature_flush),
info->gd->disk_name, flush_info(info),
"persistent grants:", info->feature_persistent ?
"enabled;" : "disabled;", "indirect descriptors:",
info->max_indirect_segments ? "enabled;" : "disabled;");
@ -1621,6 +1615,7 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
if (unlikely(error)) {
if (error == -EOPNOTSUPP)
error = 0;
info->feature_fua = 0;
info->feature_flush = 0;
xlvbd_flush(info);
}
@ -2315,6 +2310,7 @@ static void blkfront_gather_backend_features(struct blkfront_info *info)
unsigned int indirect_segments;
info->feature_flush = 0;
info->feature_fua = 0;
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
"feature-barrier", "%d", &barrier,
@ -2327,8 +2323,11 @@ static void blkfront_gather_backend_features(struct blkfront_info *info)
*
* If there are barriers, then we use flush.
*/
if (!err && barrier)
info->feature_flush = REQ_FLUSH | REQ_FUA;
if (!err && barrier) {
info->feature_flush = 1;
info->feature_fua = 1;
}
/*
* And if there is "feature-flush-cache" use that above
* barriers.
@ -2337,8 +2336,10 @@ static void blkfront_gather_backend_features(struct blkfront_info *info)
"feature-flush-cache", "%d", &flush,
NULL);
if (!err && flush)
info->feature_flush = REQ_FLUSH;
if (!err && flush) {
info->feature_flush = 1;
info->feature_fua = 0;
}
err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
"feature-discard", "%d", &discard,