[Qemu-devel] [PATCH v3 2/3] blkdebug: Extend rule check for additional types

[Marc Olson <marcolso@amazon.com>]

Break out the more common parts of the BlkdebugRule struct, and make
rule_check() more explicit about operating only on error injection types
so that additional rule types can be added in the future.

Signed-off-by: Marc Olson <marcolso@amazon.com>
---
 block/blkdebug.c | 59 +++++++++++++++++++++++++++++---------------------------
 1 file changed, 31 insertions(+), 28 deletions(-)

diff --git a/block/blkdebug.c b/block/blkdebug.c
index 327049b..7739849 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -73,13 +73,13 @@ typedef struct BlkdebugRule {
     BlkdebugEvent event;
     int action;
     int state;
+    int once;
+    int64_t offset;
     union {
         struct {
             int error;
             int immediately;
-            int once;
-            int64_t offset;
-        } inject;
+        } inject_error;
         struct {
             int new_state;
         } set_state;
@@ -182,16 +182,16 @@ static int add_rule(void *opaque, QemuOpts *opts, Error **errp)
         .state  = qemu_opt_get_number(opts, "state", 0),
     };
 
+    rule->once = qemu_opt_get_bool(opts, "once", 0);
+    sector = qemu_opt_get_number(opts, "sector", -1);
+    rule->offset = sector == -1 ? -1 : sector * BDRV_SECTOR_SIZE;
+
     /* Parse action-specific options */
     switch (d->action) {
     case ACTION_INJECT_ERROR:
-        rule->options.inject.error = qemu_opt_get_number(opts, "errno", EIO);
-        rule->options.inject.once  = qemu_opt_get_bool(opts, "once", 0);
-        rule->options.inject.immediately =
+        rule->options.inject_error.error = qemu_opt_get_number(opts, "errno", EIO);
+        rule->options.inject_error.immediately =
             qemu_opt_get_bool(opts, "immediately", 0);
-        sector = qemu_opt_get_number(opts, "sector", -1);
-        rule->options.inject.offset =
-            sector == -1 ? -1 : sector * BDRV_SECTOR_SIZE;
         break;
 
     case ACTION_SET_STATE:
@@ -474,38 +474,41 @@ static int rule_check(BlockDriverState *bs, uint64_t offset, uint64_t bytes)
 {
     BDRVBlkdebugState *s = bs->opaque;
     BlkdebugRule *rule = NULL;
+    BlkdebugRule *error_rule = NULL;
     int error;
     bool immediately;
+    int ret = 0;
 
     QSIMPLEQ_FOREACH(rule, &s->active_rules, active_next) {
-        uint64_t inject_offset = rule->options.inject.offset;
-
-        if (inject_offset == -1 ||
-            (bytes && inject_offset >= offset &&
-             inject_offset < offset + bytes))
+        if (rule->offset == -1 ||
+            (bytes && rule->offset >= offset &&
+             rule->offset < offset + bytes))
         {
-            break;
+            if (rule->action == ACTION_INJECT_ERROR) {
+                error_rule = rule;
+                break;
+            }
         }
     }
 
-    if (!rule) {
-        return 0;
-    }
+    if (error_rule) {
+        immediately = error_rule->options.inject_error.immediately;
+        error = error_rule->options.inject_error.error;
 
-    immediately = rule->options.inject.immediately;
-    error = rule->options.inject.error;
+        if (error_rule->once) {
+            QSIMPLEQ_REMOVE(&s->active_rules, error_rule, BlkdebugRule, active_next);
+            remove_rule(error_rule);
+        }
 
-    if (rule->options.inject.once) {
-        QSIMPLEQ_REMOVE(&s->active_rules, rule, BlkdebugRule, active_next);
-        remove_rule(rule);
-    }
+        if (error && !immediately) {
+            aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self());
+            qemu_coroutine_yield();
+        }
 
-    if (error && !immediately) {
-        aio_co_schedule(qemu_get_current_aio_context(), qemu_coroutine_self());
-        qemu_coroutine_yield();
+        ret = -error;
     }
 
-    return -error;
+    return ret;
 }
 
 static int coroutine_fn
-- 
2.7.4