On Tue, Dec 29, 2015 at 04:46:03PM +0800, Cao jin wrote:
Signed-off-by: Cao jin <caoj.f...@cn.fujitsu.com>
---
changelog v4:
1. strip the bugfix code, but I guess this patch should be applied after
that bugfix patch.
2. Other little fix as per previous review
Some explanation to previous review:
1. error_setg_errno() I use in this patch will print the strerror(errno), so I
guess it will be informative enough? example:
error_setg_errno(errp, errno, "open %s fail", path); will print:
"open bluhbluh fail: string_from_strerrer(errno)"
I'd prefer some mention of why this is attempted too.
E.g. "igd passthrough : open bluhbluh fail"
2. snprintf() has tiny tiny chance to fail,
It just formats a string into a buffer. the buffer
is pre-allocated, and we know it's large enough for the data.
How can it fail?
I don`t assert here, because this
device is on-board, it init during machine initialization, in case it fails,
the errp we set will results in error_report(err) and exit(1), at least can
let user know why fail. see the call-chain:
pc_xen_hvm_init_pci->pc_init1->i440fx_init->pci_create_simple->
pci_create_simple_multifunction->qdev_init_nofail
unlike open failing, there's nothing user can do, this means there's
a coding bug somewhere, and assert is easier to debug.
About test:
1. Compiled
2. Did a dirty hack to force create/realize this device in pc_init1(), prove
that the realizing process is ok, I will reply this mail later to attch the
screenshot evidence
Good job, thanks!
You should also Cc Tiejun Chen <tiejun.c...@intel.com> who wrote this
code, presumably with access to hardware to test on.
hw/pci-host/piix.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)
diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
index a9cb983..e91570f 100644
--- a/hw/pci-host/piix.c
+++ b/hw/pci-host/piix.c
@@ -761,7 +761,7 @@ static const IGDHostInfo igd_host_bridge_infos[] = {
{0xa8, 4}, /* SNB: base of GTT stolen memory */
};
-static int host_pci_config_read(int pos, int len, uint32_t *val)
+static void host_pci_config_read(int pos, int len, uint32_t *val, Error **errp)
{
char path[PATH_MAX];
int config_fd;
@@ -769,19 +769,19 @@ static int host_pci_config_read(int pos, int len,
uint32_t *val)
/* Access real host bridge. */
int rc = snprintf(path, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",
0, 0, 0, 0, "config");
- int ret = 0;
if (rc >= size || rc < 0) {
- return -ENODEV;
+ error_setg_errno(errp, errno, "snprintf err");
}
config_fd = open(path, O_RDWR);
if (config_fd < 0) {
- return -ENODEV;
+ error_setg_errno(errp, errno, "open %s fail", path);
+ return;
}
if (lseek(config_fd, pos, SEEK_SET) != pos) {
- ret = -errno;
+ error_setg_errno(errp, errno, "lseek err");
goto out;
}
@@ -789,32 +789,32 @@ static int host_pci_config_read(int pos, int len,
uint32_t *val)
rc = read(config_fd, (uint8_t *)val, len);
} while (rc < 0 && (errno == EINTR || errno == EAGAIN));
if (rc != len) {
- ret = -errno;
+ error_setg_errno(errp, errno, "read err");
}
out:
close(config_fd);
- return ret;
}
-static int igd_pt_i440fx_initfn(struct PCIDevice *pci_dev)
+static void igd_pt_i440fx_realize(struct PCIDevice *pci_dev, Error **errp)
{
uint32_t val = 0;
- int rc, i, num;
+ int i, num;
int pos, len;
+ Error *local_err = NULL;
num = ARRAY_SIZE(igd_host_bridge_infos);
for (i = 0; i < num; i++) {
pos = igd_host_bridge_infos[i].offset;
len = igd_host_bridge_infos[i].len;
- rc = host_pci_config_read(pos, len, &val);
- if (rc) {
- return -ENODEV;
+
+ host_pci_config_read(pos, len, &val, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ return;
}
pci_default_write_config(pci_dev, pos, cpu_to_le32(val), len);
}
-
- return 0;
}
static void igd_passthrough_i440fx_class_init(ObjectClass *klass, void *data)
@@ -822,7 +822,7 @@ static void igd_passthrough_i440fx_class_init(ObjectClass
*klass, void *data)
DeviceClass *dc = DEVICE_CLASS(klass);
PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
- k->init = igd_pt_i440fx_initfn;
+ k->realize = igd_pt_i440fx_realize;
dc->desc = "IGD Passthrough Host bridge";
}
--
2.1.0
.
