[RFC v5 037/126] S390 Machines: introduce ERRP_AUTO_PROPAGATE

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

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 <kwolf@redhat.com>
Reported-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 hw/s390x/ipl.c          | 24 +++++++++++-------------
 hw/s390x/s390-pci-bus.c | 37 ++++++++++++++++---------------------
 2 files changed, 27 insertions(+), 34 deletions(-)

diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c
index ca544d64c5..46b0a413cf 100644
--- a/hw/s390x/ipl.c
+++ b/hw/s390x/ipl.c
@@ -110,12 +110,12 @@ static uint64_t bios_translate_addr(void *opaque, uint64_t srcaddr)
 
 static void s390_ipl_realize(DeviceState *dev, Error **errp)
 {
+    ERRP_AUTO_PROPAGATE();
     S390IPLState *ipl = S390_IPL(dev);
     uint32_t *ipl_psw;
     uint64_t pentry;
     char *magic;
     int kernel_size;
-    Error *err = NULL;
 
     int bios_size;
     char *bios_filename;
@@ -133,8 +133,8 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp)
 
         bios_filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
         if (bios_filename == NULL) {
-            error_setg(&err, "could not find stage1 bootloader");
-            goto error;
+            error_setg(errp, "could not find stage1 bootloader");
+            return;
         }
 
         bios_size = load_elf(bios_filename, NULL,
@@ -153,8 +153,8 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp)
         g_free(bios_filename);
 
         if (bios_size == -1) {
-            error_setg(&err, "could not load bootloader '%s'", bios_name);
-            goto error;
+            error_setg(errp, "could not load bootloader '%s'", bios_name);
+            return;
         }
 
         /* default boot target is the bios */
@@ -168,8 +168,8 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp)
         if (kernel_size < 0) {
             kernel_size = load_image_targphys(ipl->kernel, 0, ram_size);
             if (kernel_size < 0) {
-                error_setg(&err, "could not load kernel '%s'", ipl->kernel);
-                goto error;
+                error_setg(errp, "could not load kernel '%s'", ipl->kernel);
+                return;
             }
             /* if this is Linux use KERN_IMAGE_START */
             magic = rom_ptr(LINUX_MAGIC_ADDR, 6);
@@ -181,8 +181,8 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp)
                 if (ipl_psw) {
                     pentry = be32_to_cpu(*ipl_psw) & 0x7fffffffUL;
                 } else {
-                    error_setg(&err, "Could not get IPL PSW");
-                    goto error;
+                    error_setg(errp, "Could not get IPL PSW");
+                    return;
                 }
             }
         }
@@ -215,8 +215,8 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp)
             initrd_size = load_image_targphys(ipl->initrd, initrd_offset,
                                               ram_size - initrd_offset);
             if (initrd_size == -1) {
-                error_setg(&err, "could not load initrd '%s'", ipl->initrd);
-                goto error;
+                error_setg(errp, "could not load initrd '%s'", ipl->initrd);
+                return;
             }
 
             /*
@@ -238,8 +238,6 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp)
     ipl->compat_start_addr = ipl->start_addr;
     ipl->compat_bios_start_addr = ipl->bios_start_addr;
     qemu_register_reset(qdev_reset_all_fn, dev);
-error:
-    error_propagate(errp, err);
 }
 
 static Property s390_ipl_properties[] = {
diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 2d2f4a7c41..273e32d4ae 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -737,11 +737,11 @@ static void s390_pci_iommu_free(S390pciState *s, PCIBus *bus, int32_t devfn)
 
 static void s390_pcihost_realize(DeviceState *dev, Error **errp)
 {
+    ERRP_AUTO_PROPAGATE();
     PCIBus *b;
     BusState *bus;
     PCIHostState *phb = PCI_HOST_BRIDGE(dev);
     S390pciState *s = S390_PCI_HOST_BRIDGE(dev);
-    Error *local_err = NULL;
 
     DPRINTF("host_init\n");
 
@@ -751,17 +751,15 @@ static void s390_pcihost_realize(DeviceState *dev, Error **errp)
     pci_setup_iommu(b, s390_pci_dma_iommu, s);
 
     bus = BUS(b);
-    qbus_set_hotplug_handler(bus, OBJECT(dev), &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
+    qbus_set_hotplug_handler(bus, OBJECT(dev), errp);
+    if (*errp) {
         return;
     }
     phb->bus = b;
 
     s->bus = S390_PCI_BUS(qbus_create(TYPE_S390_PCI_BUS, dev, NULL));
-    qbus_set_hotplug_handler(BUS(s->bus), OBJECT(dev), &local_err);
-    if (local_err) {
-        error_propagate(errp, local_err);
+    qbus_set_hotplug_handler(BUS(s->bus), OBJECT(dev), errp);
+    if (*errp) {
         return;
     }
 
@@ -773,8 +771,7 @@ static void s390_pcihost_realize(DeviceState *dev, Error **errp)
     QTAILQ_INIT(&s->zpci_devs);
 
     css_register_io_adapters(CSS_IO_ADAPTER_PCI, true, false,
-                             S390_ADAPTER_SUPPRESSIBLE, &local_err);
-    error_propagate(errp, local_err);
+                             S390_ADAPTER_SUPPRESSIBLE, errp);
 }
 
 static int s390_pci_msix_init(S390PCIBusDevice *pbdev)
@@ -821,7 +818,7 @@ static void s390_pci_msix_free(S390PCIBusDevice *pbdev)
 static S390PCIBusDevice *s390_pci_device_new(S390pciState *s,
                                              const char *target, Error **errp)
 {
-    Error *local_err = NULL;
+    ERRP_AUTO_PROPAGATE();
     DeviceState *dev;
 
     dev = qdev_try_create(BUS(s->bus), TYPE_S390_PCI_DEVICE);
@@ -830,17 +827,17 @@ static S390PCIBusDevice *s390_pci_device_new(S390pciState *s,
         return NULL;
     }
 
-    object_property_set_str(OBJECT(dev), target, "target", &local_err);
-    if (local_err) {
+    object_property_set_str(OBJECT(dev), target, "target", errp);
+    if (*errp) {
         object_unparent(OBJECT(dev));
-        error_propagate_prepend(errp, local_err,
+        error_prepend(errp,
                                 "zPCI device could not be created: ");
         return NULL;
     }
-    object_property_set_bool(OBJECT(dev), true, "realized", &local_err);
-    if (local_err) {
+    object_property_set_bool(OBJECT(dev), true, "realized", errp);
+    if (*errp) {
         object_unparent(OBJECT(dev));
-        error_propagate_prepend(errp, local_err,
+        error_prepend(errp,
                                 "zPCI device could not be created: ");
         return NULL;
     }
@@ -1187,6 +1184,7 @@ static uint32_t s390_pci_generate_fid(S390pciState *s, Error **errp)
 
 static void s390_pci_device_realize(DeviceState *dev, Error **errp)
 {
+    ERRP_AUTO_PROPAGATE();
     S390PCIBusDevice *zpci = S390_PCI_DEVICE(dev);
     S390pciState *s = s390_get_phb();
 
@@ -1213,11 +1211,8 @@ static void s390_pci_device_realize(DeviceState *dev, Error **errp)
     }
 
     if (!zpci->fid_defined) {
-        Error *local_error = NULL;
-
-        zpci->fid = s390_pci_generate_fid(s, &local_error);
-        if (local_error) {
-            error_propagate(errp, local_error);
+        zpci->fid = s390_pci_generate_fid(s, errp);
+        if (*errp) {
             return;
         }
     } else if (s390_pci_find_dev_by_fid(s, zpci->fid)) {
-- 
2.21.0