linux-kernel - Re: [PATCH] PCI: create device, function symlinks in /sys/bus/pci/slots/N/

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20080819163755.GB8318@parisc-linux.org>
Date:	Tue, 19 Aug 2008 10:37:56 -0600
From:	Matthew Wilcox <matthew@....cx>
To:	Alex Chiang <achiang@...com>, jbarnes@...tuousgeek.org,
	linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] PCI: create device, function symlinks in /sys/bus/pci/slots/N/

On Mon, Aug 18, 2008 at 02:21:00PM -0600, Alex Chiang wrote:
> The original form of this patch was written by Matthew Wilcox,
> but did not have links from the sysfs slots/ directory pointing
> back at devices and functions.

I think the reason I didn't bother was that you could already get this
information from the 'address' file.  ie:

$ ls -l /sys/bus/pci/devices/`cat /sys/bus/pci/slots/3/address`*

But I don't think we had a way to go from a device to the slot it's in,
without searching through all the slots for matching address.

> +static void remove_sysfs_files(struct pci_slot *slot)
> +{
> +	char func[10];
> +	struct list_head *tmp;
> +
> +	list_for_each(tmp, &slot->bus->devices) {
> +		struct pci_dev *dev = pci_dev_b(tmp);
> +		if (PCI_SLOT(dev->devfn) != slot->number)
> +			continue;
> +		sysfs_remove_link(&dev->dev.kobj, "slot");
> +
> +		snprintf(func, 10, "function%d", PCI_FUNC(dev->devfn));
> +		sysfs_remove_link(&slot->kobj, func);
> +	}
> +	sysfs_remove_link(&slot->kobj, "device");
> +}
> +
> +static int create_sysfs_files(struct pci_slot *slot)
> +{
> +	int result, lastdev = -1;
> +	char func[10];
> +	struct list_head *tmp;
> +
> +	list_for_each(tmp, &slot->bus->devices) {
> +		struct pci_dev *dev = pci_dev_b(tmp);
> +		if (PCI_SLOT(dev->devfn) != slot->number)
> +			continue;

Why not use pci_get_slot()?

> +		result = sysfs_create_link(&dev->dev.kobj, &slot->kobj, "slot");
> +		if (result)
> +			goto fail;
> +
> +		if (PCI_SLOT(dev->devfn) != lastdev) {
> +			lastdev = PCI_SLOT(dev->devfn);
> +			result = sysfs_create_link(&slot->kobj,
> +						   &dev->dev.kobj,
> +						   "device");
> +			if (result)
> +				goto fail;
> +		}
> +
> +		snprintf(func, 10, "function%d", PCI_FUNC(dev->devfn));
> +		result = sysfs_create_link(&slot->kobj, &dev->dev.kobj, func);
> +		if (result)
> +			goto fail;
> +	}
> +
> +	return 0;
> +
> +fail:
> +	remove_sysfs_files(slot);
> +	return result;
> +}
> +
>  static void pci_slot_release(struct kobject *kobj)
>  {
>  	struct pci_slot *slot = to_pci_slot(kobj);
> @@ -54,6 +108,8 @@ static void pci_slot_release(struct kobject *kobj)
>  	pr_debug("%s: releasing pci_slot on %x:%d\n", __func__,
>  		 slot->bus->number, slot->number);
>  
> +	remove_sysfs_files(slot);
> +
>  	list_del(&slot->list);
>  
>  	kfree(slot);
> @@ -150,6 +206,8 @@ placeholder:
>  	INIT_LIST_HEAD(&slot->list);
>  	list_add(&slot->list, &parent->slots);
>  
> +	create_sysfs_files(slot);
> +
>  	/* Don't care if debug printk has a -1 for slot_nr */
>  	pr_debug("%s: created pci_slot on %04x:%02x:%02x\n",
>  		 __func__, pci_domain_nr(parent), parent->number, slot_nr);
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 
Intel are signing my paycheques ... these opinions are still mine
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours.  We can't possibly take such
a retrograde step."
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/