On error path (like i/o error in one of the coroutines), it's required to
- wait for coroutines completion before cleaning the common structures
- reenter dependent coroutines so they ever finish
Introduced in 2d9187bc65.
Signed-off-by: Anton Nefedov <anton.nefe...@virtuozzo.com>
---
qemu-img.c | 44 +++++++++++++++++++++++++++-----------------
1 file changed, 27 insertions(+), 17 deletions(-)
diff --git a/qemu-img.c b/qemu-img.c
index b220cf7..24950c1 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1735,6 +1735,27 @@ static int coroutine_fn convert_co_write(ImgConvertState
*s, int64_t sector_num,
return 0;
}
+static void coroutine_fn convert_reenter_waiting(ImgConvertState *s,
+ uint64_t wr_offs)
+{
+ int i;
+ if (s->wr_in_order) {
+ /* reenter the coroutine that might have waited
+ * for the write to complete */
+ for (i = 0; i < s->num_coroutines; i++) {
+ if (s->co[i] && s->wait_sector_num[i] == wr_offs) {
+ /*
+ * A -> B -> A cannot occur because A has
+ * s->wait_sector_num[i] == -1 during A -> B. Therefore
+ * B will never enter A during this time window.
+ */
+ qemu_coroutine_enter(s->co[i]);
+ break;
+ }
+ }
+ }
+}
+
static void coroutine_fn convert_co_do_copy(void *opaque)
{
ImgConvertState *s = opaque;
@@ -1792,6 +1813,7 @@ static void coroutine_fn convert_co_do_copy(void *opaque)
error_report("error while reading sector %" PRId64
": %s", sector_num, strerror(-ret));
s->ret = ret;
+ convert_reenter_waiting(s, sector_num + n);
goto out;
}
} else if (!s->min_sparse && status == BLK_ZERO) {
@@ -1803,6 +1825,7 @@ static void coroutine_fn convert_co_do_copy(void *opaque)
/* keep writes in order */
while (s->wr_offs != sector_num) {
if (s->ret != -EINPROGRESS) {
+ convert_reenter_waiting(s, sector_num + n);
goto out;
}
s->wait_sector_num[index] = sector_num;
@@ -1816,25 +1839,12 @@ static void coroutine_fn convert_co_do_copy(void
*opaque)
error_report("error while writing sector %" PRId64
": %s", sector_num, strerror(-ret));
s->ret = ret;
+ convert_reenter_waiting(s, sector_num + n);
goto out;
}
- if (s->wr_in_order) {
- /* reenter the coroutine that might have waited
- * for this write to complete */
- s->wr_offs = sector_num + n;
- for (i = 0; i < s->num_coroutines; i++) {
- if (s->co[i] && s->wait_sector_num[i] == s->wr_offs) {
- /*
- * A -> B -> A cannot occur because A has
- * s->wait_sector_num[i] == -1 during A -> B. Therefore
- * B will never enter A during this time window.
- */
- qemu_coroutine_enter(s->co[i]);
- break;
- }
- }
- }
+ s->wr_offs = sector_num + n;
+ convert_reenter_waiting(s, s->wr_offs);
}
out:
@@ -1899,7 +1909,7 @@ static int convert_do_copy(ImgConvertState *s)
qemu_coroutine_enter(s->co[i]);
}
- while (s->ret == -EINPROGRESS) {
+ while (s->running_coroutines) {
main_loop_wait(false);
}
--
2.7.4
