[PATCH 33/35] block, drivers: add REQ_OP_FLUSH operation
From: Mike Christie
This adds a REQ_OP_FLUSH operation that is sent to request_fn
based drivers by the block layer's flush code, instead of
sending requests with the request->cmd_flags REQ_FLUSH bit set.
For the following 3 flush related patches, I have not tested
every driver. I have only tested scsi with xfs and btrfs.
v2.
1. Fix kbuild failures. Forgot to update ubd driver.
Signed-off-by: Mike Christie
---
Documentation/block/writeback_cache_control.txt | 6 +++---
arch/um/drivers/ubd_kern.c | 2 +-
block/blk-flush.c | 6 +++---
drivers/block/loop.c| 4 ++--
drivers/block/nbd.c | 2 +-
drivers/block/osdblk.c | 2 +-
drivers/block/ps3disk.c | 4 ++--
drivers/block/skd_main.c| 2 +-
drivers/block/virtio_blk.c | 2 +-
drivers/block/xen-blkfront.c| 8
drivers/ide/ide-disk.c | 2 +-
drivers/md/dm.c | 2 +-
drivers/mmc/card/block.c| 5 ++---
drivers/mmc/card/queue.h| 2 +-
drivers/mtd/mtd_blkdevs.c | 2 +-
drivers/nvme/host/pci.c | 2 +-
drivers/scsi/sd.c | 7 +++
include/linux/blk_types.h | 1 +
include/linux/blkdev.h | 3 +++
kernel/trace/blktrace.c | 5 -
20 files changed, 37 insertions(+), 32 deletions(-)
diff --git a/Documentation/block/writeback_cache_control.txt
b/Documentation/block/writeback_cache_control.txt
index 83407d3..ea5550f 100644
--- a/Documentation/block/writeback_cache_control.txt
+++ b/Documentation/block/writeback_cache_control.txt
@@ -73,9 +73,9 @@ doing:
blk_queue_flush(sdkp->disk->queue, REQ_FLUSH);
-and handle empty REQ_FLUSH requests in its prep_fn/request_fn. Note that
+and handle empty REQ_OP_FLUSH requests in its prep_fn/request_fn. Note that
REQ_FLUSH requests with a payload are automatically turned into a sequence
-of an empty REQ_FLUSH request followed by the actual write by the block
+of an empty REQ_OP_FLUSH request followed by the actual write by the block
layer. For devices that also support the FUA bit the block layer needs
to be told to pass through the REQ_FUA bit using:
@@ -83,4 +83,4 @@ to be told to pass through the REQ_FUA bit using:
and the driver must handle write requests that have the REQ_FUA bit set
in prep_fn/request_fn. If the FUA bit is not natively supported the block
-layer turns it into an empty REQ_FLUSH request after the actual write.
+layer turns it into an empty REQ_OP_FLUSH request after the actual write.
diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 39ba207..a7dc382 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -1286,7 +1286,7 @@ static void do_ubd_request(struct request_queue *q)
req = dev->request;
- if (req->cmd_flags & REQ_FLUSH) {
+ if (req->op == REQ_OP_FLUSH) {
io_req = kmalloc(sizeof(struct io_thread_req),
GFP_ATOMIC);
if (io_req == NULL) {
diff --git a/block/blk-flush.c b/block/blk-flush.c
index e01d3ac..070d7c7 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -29,7 +29,7 @@
* The actual execution of flush is double buffered. Whenever a request
* needs to execute PRE or POSTFLUSH, it queues at
* fq->flush_queue[fq->flush_pending_idx]. Once certain criteria are met, a
- * flush is issued and the pending_idx is toggled. When the flush
+ * REQ_OP_FLUSH is issued and the pending_idx is toggled. When the flush
* completes, all the requests which were pending are proceeded to the next
* step. This allows arbitrary merging of different types of FLUSH/FUA
* requests.
@@ -329,8 +329,8 @@ static bool blk_kick_flush(struct request_queue *q, struct
blk_flush_queue *fq)
}
flush_rq->cmd_type = REQ_TYPE_FS;
- flush_rq->cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ;
- flush_rq->op = REQ_OP_WRITE;
+ flush_rq->cmd_flags = REQ_SYNC | REQ_NOIDLE | REQ_FLUSH_SEQ;
+ flush_rq->op = REQ_OP_FLUSH;
flush_rq->rq_disk = first_rq->rq_disk;
flush_rq->end_io = flush_end_io;
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 1afc03c..a3d1293 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -536,7 +536,7 @@ static int do_req_filebacked(struct loop_device *lo, struct
request *rq)
pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
if (op_is_write(rq->op)) {
- if (rq->cmd_flags & REQ_FLUSH)
+ if (rq->op == REQ_OP_FLUSH)
ret = lo_req_flush(lo, rq);
else if (rq->op == REQ_OP_D
[PATCH 33/35] block, drivers: add REQ_OP_FLUSH operation
From: Mike Christie
This adds a REQ_OP_FLUSH operation that is sent to request_fn
based drivers by the block layer's flush code, instead of
sending requests with the request->cmd_flags REQ_FLUSH bit set.
For the following 3 flush related patches, I have not tested
every driver. I have only tested scsi with xfs and btrfs.
Signed-off-by: Mike Christie
---
Documentation/block/writeback_cache_control.txt | 6 +++---
block/blk-flush.c | 6 +++---
drivers/block/loop.c| 4 ++--
drivers/block/nbd.c | 2 +-
drivers/block/osdblk.c | 2 +-
drivers/block/ps3disk.c | 4 ++--
drivers/block/skd_main.c| 2 +-
drivers/block/virtio_blk.c | 2 +-
drivers/block/xen-blkfront.c| 8
drivers/ide/ide-disk.c | 2 +-
drivers/md/dm.c | 4 ++--
drivers/mmc/card/block.c| 5 ++---
drivers/mmc/card/queue.h| 2 +-
drivers/mtd/mtd_blkdevs.c | 2 +-
drivers/nvme/host/pci.c | 2 +-
drivers/scsi/sd.c | 7 +++
include/linux/blk_types.h | 1 +
include/linux/blkdev.h | 3 +++
kernel/trace/blktrace.c | 5 -
19 files changed, 37 insertions(+), 32 deletions(-)
diff --git a/Documentation/block/writeback_cache_control.txt
b/Documentation/block/writeback_cache_control.txt
index 83407d3..ea5550f 100644
--- a/Documentation/block/writeback_cache_control.txt
+++ b/Documentation/block/writeback_cache_control.txt
@@ -73,9 +73,9 @@ doing:
blk_queue_flush(sdkp->disk->queue, REQ_FLUSH);
-and handle empty REQ_FLUSH requests in its prep_fn/request_fn. Note that
+and handle empty REQ_OP_FLUSH requests in its prep_fn/request_fn. Note that
REQ_FLUSH requests with a payload are automatically turned into a sequence
-of an empty REQ_FLUSH request followed by the actual write by the block
+of an empty REQ_OP_FLUSH request followed by the actual write by the block
layer. For devices that also support the FUA bit the block layer needs
to be told to pass through the REQ_FUA bit using:
@@ -83,4 +83,4 @@ to be told to pass through the REQ_FUA bit using:
and the driver must handle write requests that have the REQ_FUA bit set
in prep_fn/request_fn. If the FUA bit is not natively supported the block
-layer turns it into an empty REQ_FLUSH request after the actual write.
+layer turns it into an empty REQ_OP_FLUSH request after the actual write.
diff --git a/block/blk-flush.c b/block/blk-flush.c
index b4eb0e8..0e5561e 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -29,7 +29,7 @@
* The actual execution of flush is double buffered. Whenever a request
* needs to execute PRE or POSTFLUSH, it queues at
* fq->flush_queue[fq->flush_pending_idx]. Once certain criteria are met, a
- * flush is issued and the pending_idx is toggled. When the flush
+ * REQ_OP_FLUSH is issued and the pending_idx is toggled. When the flush
* completes, all the requests which were pending are proceeded to the next
* step. This allows arbitrary merging of different types of FLUSH/FUA
* requests.
@@ -329,8 +329,8 @@ static bool blk_kick_flush(struct request_queue *q, struct
blk_flush_queue *fq)
}
flush_rq->cmd_type = REQ_TYPE_FS;
- flush_rq->cmd_flags = WRITE_FLUSH | REQ_FLUSH_SEQ;
- flush_rq->op = REQ_OP_WRITE;
+ flush_rq->cmd_flags = REQ_SYNC | REQ_NOIDLE | REQ_FLUSH_SEQ;
+ flush_rq->op = REQ_OP_FLUSH;
flush_rq->rq_disk = first_rq->rq_disk;
flush_rq->end_io = flush_end_io;
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 1afc03c..a3d1293 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -536,7 +536,7 @@ static int do_req_filebacked(struct loop_device *lo, struct
request *rq)
pos = ((loff_t) blk_rq_pos(rq) << 9) + lo->lo_offset;
if (op_is_write(rq->op)) {
- if (rq->cmd_flags & REQ_FLUSH)
+ if (rq->op == REQ_OP_FLUSH)
ret = lo_req_flush(lo, rq);
else if (rq->op == REQ_OP_DISCARD)
ret = lo_discard(lo, rq, pos);
@@ -1653,7 +1653,7 @@ static int loop_queue_rq(struct blk_mq_hw_ctx *hctx,
if (lo->lo_state != Lo_bound)
return -EIO;
- if (lo->use_dio && (!(cmd->rq->cmd_flags & REQ_FLUSH) ||
+ if (lo->use_dio && (cmd->rq->op != REQ_OP_FLUSH ||
cmd->rq->op == REQ_OP_DISCARD))
cmd->use_aio = true;
else
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 8e8f7e3..ced3382 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -244,7 +244,7 @@ static int nbd_send_req(struct nbd_device *nbd, struct
request *req)
