[RFC v5 051/126] vfio-ccw: introduce ERRP_AUTO_PROPAGATE

[Vladimir Sementsov-Ogievskiy]

If we want to add some info to errp (by error_prepend() or
error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
Otherwise, this info will not be added when errp == &fatal_err
(the program will exit prior to the error_append_hint() or
error_prepend() call).  Fix such cases.

If we want to check error after errp-function call, we need to
introduce local_err and than propagate it to errp. Instead, use
ERRP_AUTO_PROPAGATE macro, benefits are:
1. No need of explicit error_propagate call
2. No need of explicit local_err variable: use errp directly
3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
   &error_fatel, this means that we don't break error_abort
   (we'll abort on error_set, not on error_propagate)

This commit (together with its neighbors) was generated by

for f in $(git grep -l errp \*.[ch]); do \
    spatch --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
    --macro-file scripts/cocci-macro-file.h --in-place --no-show-diff $f; \
done;

then fix a bit of compilation problems: coccinelle for some reason
leaves several
f() {
    ...
    goto out;
    ...
    out:
}
patterns, with "out:" at function end.

then
./python/commit-per-subsystem.py MAINTAINERS "$(< auto-msg)"

(auto-msg was a file with this commit message)

Still, for backporting it may be more comfortable to use only the first
command and then do one huge commit.

Reported-by: Kevin Wolf <address@hidden>
Reported-by: Greg Kurz <address@hidden>
Signed-off-by: Vladimir Sementsov-Ogievskiy <address@hidden>
---
 hw/s390x/s390-ccw.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/hw/s390x/s390-ccw.c b/hw/s390x/s390-ccw.c
index 0c5a5b60bd..415fa04091 100644
--- a/hw/s390x/s390-ccw.c
+++ b/hw/s390x/s390-ccw.c
@@ -55,6 +55,7 @@ static void s390_ccw_get_dev_info(S390CCWDevice *cdev,
                                   char *sysfsdev,
                                   Error **errp)
 {
+    ERRP_AUTO_PROPAGATE();
     unsigned int cssid, ssid, devid;
     char dev_path[PATH_MAX] = {0}, *tmp;
 
@@ -86,19 +87,19 @@ static void s390_ccw_get_dev_info(S390CCWDevice *cdev,
 
 static void s390_ccw_realize(S390CCWDevice *cdev, char *sysfsdev, Error **errp)
 {
+    ERRP_AUTO_PROPAGATE();
     CcwDevice *ccw_dev = CCW_DEVICE(cdev);
     CCWDeviceClass *ck = CCW_DEVICE_GET_CLASS(ccw_dev);
     DeviceState *parent = DEVICE(ccw_dev);
     SubchDev *sch;
     int ret;
-    Error *err = NULL;
 
-    s390_ccw_get_dev_info(cdev, sysfsdev, &err);
-    if (err) {
-        goto out_err_propagate;
+    s390_ccw_get_dev_info(cdev, sysfsdev, errp);
+    if (*errp) {
+        return;
     }
 
-    sch = css_create_sch(ccw_dev->devno, &err);
+    sch = css_create_sch(ccw_dev->devno, errp);
     if (!sch) {
         goto out_mdevid_free;
     }
@@ -108,13 +109,13 @@ static void s390_ccw_realize(S390CCWDevice *cdev, char 
*sysfsdev, Error **errp)
     ccw_dev->sch = sch;
     ret = css_sch_build_schib(sch, &cdev->hostid);
     if (ret) {
-        error_setg_errno(&err, -ret, "%s: Failed to build initial schib",
+        error_setg_errno(errp, -ret, "%s: Failed to build initial schib",
                          __func__);
         goto out_err;
     }
 
-    ck->realize(ccw_dev, &err);
-    if (err) {
+    ck->realize(ccw_dev, errp);
+    if (*errp) {
         goto out_err;
     }
 
@@ -128,8 +129,6 @@ out_err:
     g_free(sch);
 out_mdevid_free:
     g_free(cdev->mdevid);
-out_err_propagate:
-    error_propagate(errp, err);
 }
 
 static void s390_ccw_unrealize(S390CCWDevice *cdev, Error **errp)
-- 
2.21.0