Author: bryanv
Date: Tue Jan 27 05:34:46 2015
New Revision: 277788
URL: https://svnweb.freebsd.org/changeset/base/277788
Log:
Rework vtblk dump handling of in flight requests
Previously, the driver resets the device and abandon the requests that
are caught in flight when the dump was initiated. This was problematic
if the system is resumed after the dump is completed.
While that is probably not the typical action, it is simple to rework
the driver to very likely have the device usable after the dump without
making it more likely for the dump to fail. The in flight requests are
simply queued for completion once the dump is finished.
Requested by: markj
MFC after:1 month
Modified:
head/sys/dev/virtio/block/virtio_blk.c
Modified: head/sys/dev/virtio/block/virtio_blk.c
==
--- head/sys/dev/virtio/block/virtio_blk.c Tue Jan 27 04:06:47 2015
(r277787)
+++ head/sys/dev/virtio/block/virtio_blk.c Tue Jan 27 05:34:46 2015
(r277788)
@@ -76,9 +76,8 @@ struct vtblk_softc {
#define VTBLK_FLAG_READONLY0x0002
#define VTBLK_FLAG_DETACH 0x0004
#define VTBLK_FLAG_SUSPEND 0x0008
-#define VTBLK_FLAG_DUMPING 0x0010
-#define VTBLK_FLAG_BARRIER 0x0020
-#define VTBLK_FLAG_WC_CONFIG 0x0040
+#define VTBLK_FLAG_BARRIER 0x0010
+#define VTBLK_FLAG_WC_CONFIG 0x0020
struct virtqueue*vtblk_vq;
struct sglist *vtblk_sglist;
@@ -95,6 +94,7 @@ struct vtblk_softc {
int vtblk_request_count;
enum vtblk_cache_modevtblk_write_cache;
+ struct bio_queue vtblk_dump_queue;
struct vtblk_request vtblk_dump_request;
};
@@ -162,7 +162,7 @@ static void vtblk_queue_completed(struct
struct bio_queue *);
static voidvtblk_done_completed(struct vtblk_softc *,
struct bio_queue *);
-static voidvtblk_drain_vq(struct vtblk_softc *, int);
+static voidvtblk_drain_vq(struct vtblk_softc *);
static voidvtblk_drain(struct vtblk_softc *);
static voidvtblk_startio(struct vtblk_softc *);
@@ -177,9 +177,10 @@ static int vtblk_quiesce(struct vtblk_so
static voidvtblk_vq_intr(void *);
static voidvtblk_stop(struct vtblk_softc *);
-static voidvtblk_dump_prepare(struct vtblk_softc *);
+static voidvtblk_dump_quiesce(struct vtblk_softc *);
static int vtblk_dump_write(struct vtblk_softc *, void *, off_t, size_t);
static int vtblk_dump_flush(struct vtblk_softc *);
+static voidvtblk_dump_complete(struct vtblk_softc *);
static voidvtblk_set_write_cache(struct vtblk_softc *, int);
static int vtblk_write_cache_enabled(struct vtblk_softc *sc,
@@ -302,6 +303,7 @@ vtblk_attach(device_t dev)
sc-vtblk_dev = dev;
VTBLK_LOCK_INIT(sc, device_get_nameunit(dev));
bioq_init(sc-vtblk_bioq);
+ TAILQ_INIT(sc-vtblk_dump_queue);
TAILQ_INIT(sc-vtblk_req_free);
TAILQ_INIT(sc-vtblk_req_ready);
@@ -506,25 +508,19 @@ vtblk_dump(void *arg, void *virtual, vm_
int error;
dp = arg;
+ error = 0;
if ((sc = dp-d_drv1) == NULL)
return (ENXIO);
VTBLK_LOCK(sc);
- if ((sc-vtblk_flags VTBLK_FLAG_DUMPING) == 0) {
- vtblk_dump_prepare(sc);
- sc-vtblk_flags |= VTBLK_FLAG_DUMPING;
- }
+ vtblk_dump_quiesce(sc);
if (length 0)
error = vtblk_dump_write(sc, virtual, offset, length);
- else if (virtual == NULL offset == 0)
- error = vtblk_dump_flush(sc);
- else {
- error = EINVAL;
- sc-vtblk_flags = ~VTBLK_FLAG_DUMPING;
- }
+ if (error || (virtual == NULL offset == 0))
+ vtblk_dump_complete(sc);
VTBLK_UNLOCK(sc);
@@ -996,7 +992,7 @@ vtblk_done_completed(struct vtblk_softc
}
static void
-vtblk_drain_vq(struct vtblk_softc *sc, int skip_done)
+vtblk_drain_vq(struct vtblk_softc *sc)
{
struct virtqueue *vq;
struct vtblk_request *req;
@@ -1006,9 +1002,7 @@ vtblk_drain_vq(struct vtblk_softc *sc, i
last = 0;
while ((req = virtqueue_drain(vq, last)) != NULL) {
- if (!skip_done)
- vtblk_bio_done(sc, req-vbr_bp, ENXIO);
-
+ vtblk_bio_done(sc, req-vbr_bp, ENXIO);
vtblk_request_enqueue(sc, req);
}
@@ -1031,7 +1025,7 @@ vtblk_drain(struct vtblk_softc *sc)
vtblk_queue_completed(sc, queue);
vtblk_done_completed(sc, queue);
- vtblk_drain_vq(sc, 0);
+ vtblk_drain_vq(sc);
}
while ((req = vtblk_request_next_ready(sc)) != NULL) {
@@ -1256,31 +1250,16 @@ vtblk_stop(struct vtblk_softc *sc)
}
static void
-vtblk_dump_prepare(struct vtblk_softc *sc)
+vtblk_dump_quiesce(struct vtblk_softc *sc)
{
-
