diff mbox series

[v2,1/3] block/commit: implement final flush

Message ID 20240626145038.458709-2-vsementsov@yandex-team.ru (mailing list archive)
State New
Headers show
Series block-jobs: add final flush | expand

Commit Message

Vladimir Sementsov-Ogievskiy June 26, 2024, 2:50 p.m. UTC
Actually block job is not completed without the final flush. It's
rather unexpected to have broken target when job was successfully
completed long ago and now we fail to flush or process just
crashed/killed.

Mirror job already has mirror_flush() for this. So, it's OK.

Do this for commit job too.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---
 block/commit.c | 41 +++++++++++++++++++++++++++--------------
 1 file changed, 27 insertions(+), 14 deletions(-)
diff mbox series

Patch

diff --git a/block/commit.c b/block/commit.c
index 7c3fdcb0ca..81971692a2 100644
--- a/block/commit.c
+++ b/block/commit.c
@@ -134,6 +134,7 @@  static int coroutine_fn commit_run(Job *job, Error **errp)
     int64_t n = 0; /* bytes */
     QEMU_AUTO_VFREE void *buf = NULL;
     int64_t len, base_len;
+    bool need_final_flush = true;
 
     len = blk_co_getlength(s->top);
     if (len < 0) {
@@ -155,8 +156,8 @@  static int coroutine_fn commit_run(Job *job, Error **errp)
 
     buf = blk_blockalign(s->top, COMMIT_BUFFER_SIZE);
 
-    for (offset = 0; offset < len; offset += n) {
-        bool copy;
+    for (offset = 0; offset < len || need_final_flush; offset += n) {
+        bool copy = false;
         bool error_in_source = true;
 
         /* Note that even when no rate limit is applied we need to yield
@@ -166,22 +167,34 @@  static int coroutine_fn commit_run(Job *job, Error **errp)
         if (job_is_cancelled(&s->common.job)) {
             break;
         }
-        /* Copy if allocated above the base */
-        ret = blk_co_is_allocated_above(s->top, s->base_overlay, true,
-                                        offset, COMMIT_BUFFER_SIZE, &n);
-        copy = (ret > 0);
-        trace_commit_one_iteration(s, offset, n, ret);
-        if (copy) {
-            assert(n < SIZE_MAX);
 
-            ret = blk_co_pread(s->top, offset, n, buf, 0);
-            if (ret >= 0) {
-                ret = blk_co_pwrite(s->base, offset, n, buf, 0);
-                if (ret < 0) {
-                    error_in_source = false;
+        if (offset < len) {
+            /* Copy if allocated above the base */
+            ret = blk_co_is_allocated_above(s->top, s->base_overlay, true,
+                                            offset, COMMIT_BUFFER_SIZE, &n);
+            copy = (ret > 0);
+            trace_commit_one_iteration(s, offset, n, ret);
+            if (copy) {
+                assert(n < SIZE_MAX);
+
+                ret = blk_co_pread(s->top, offset, n, buf, 0);
+                if (ret >= 0) {
+                    ret = blk_co_pwrite(s->base, offset, n, buf, 0);
+                    if (ret < 0) {
+                        error_in_source = false;
+                    }
                 }
             }
+        } else {
+            assert(need_final_flush);
+            ret = blk_co_flush(s->base);
+            if (ret < 0) {
+                error_in_source = false;
+            } else {
+                need_final_flush = false;
+            }
         }
+
         if (ret < 0) {
             BlockErrorAction action =
                 block_job_error_action(&s->common, s->on_error,