Date: Sat, 15 Jan 2000 11:32:37 +0800 (WST) From: Michael Kennett <mike@laurasia.com.au> To: hackers@freebsd.org Subject: Use of newbus in sys/pci/pci.c Message-ID: <200001150332.LAA24167@laurasia.com.au>
next in thread | raw e-mail | index | archive | help
Hello All,
I have a question on the sys/pci/pci.c code, and its use of the
newbus architecture. An example of the code in question is:
static struct resource *
pci_alloc_resource(device_t dev, device_t child, int type, int *rid,
u_long start, u_long end, u_long count, u_int flags)
{
struct pci_devinfo *dinfo = device_get_ivars(child);
^^^^^ Looks wrong
struct resource_list *rl = &dinfo->resources;
return resource_list_alloc(rl, dev, child, type, rid,
start, end, count, flags);
}
I don't understand the line that extracts the ivars from the child
device. Isn't it the case that the ivars are a property of the bus
device (dev)? In any case, the child device might not be directly
descended from the pci bus (e.g. it could be attached thru' the
bridge isab0: <VIA 82C586 PCI-ISA bridge>).
It strikes me that the assignment is unsafe. I would have thought
that the code should be:
static struct resource *
pci_alloc_resource(device_t dev, device_t child, int type, int *rid,
u_long start, u_long end, u_long count, u_int flags)
{
struct pci_devinfo *dinfo = device_get_ivars(dev);
^^^ CHANGED
struct resource_list *rl = &dinfo->resources;
return resource_list_alloc(rl, dev, child, type, rid,
start, end, count, flags);
}
Why are the ivars extracted from the child, and not the bus device?
Kind Regards,
Mike Kennett
(mike@laurasia.com.au)
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200001150332.LAA24167>