From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933076AbcIVIpy (ORCPT ); Thu, 22 Sep 2016 04:45:54 -0400 Received: from mx2.suse.de ([195.135.220.15]:58651 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756289AbcIVIpr (ORCPT ); Thu, 22 Sep 2016 04:45:47 -0400 From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com, david.vrabel@citrix.com, Juergen Gross Subject: [PATCH v3 2/3] xen/pciback: avoid multiple entries in slot list Date: Thu, 22 Sep 2016 10:45:40 +0200 Message-Id: <1474533941-6976-3-git-send-email-jgross@suse.com> X-Mailer: git-send-email 2.6.6 In-Reply-To: <1474533941-6976-1-git-send-email-jgross@suse.com> References: <1474533941-6976-1-git-send-email-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The Xen pciback driver has a list of all pci devices it is ready to seize. There is no check whether a to be added entry already exists. While this might be no problem in the common case it might confuse those which consume the list via sysfs. Modify the handling of this list by not adding an entry which already exists. As this will be needed later split out the list handling into a separate function. Signed-off-by: Juergen Gross --- drivers/xen/xen-pciback/pci_stub.c | 39 ++++++++++++++++++++++++++++++-------- 1 file changed, 31 insertions(+), 8 deletions(-) diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 79a9e4d..0179333 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -478,6 +478,36 @@ static int __init pcistub_init_devices_late(void) return 0; } +static void pcistub_device_id_add_list(struct pcistub_device_id *new, + int domain, int bus, unsigned int devfn) +{ + struct pcistub_device_id *pci_dev_id; + unsigned long flags; + int found = 0; + + spin_lock_irqsave(&device_ids_lock, flags); + + list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) { + if (pci_dev_id->domain == domain && pci_dev_id->bus == bus && + pci_dev_id->devfn == devfn) { + found = 1; + break; + } + } + + if (!found) { + new->domain = domain; + new->bus = bus; + new->devfn = devfn; + list_add_tail(&new->slot_list, &pcistub_device_ids); + } + + spin_unlock_irqrestore(&device_ids_lock, flags); + + if (found) + kfree(new); +} + static int pcistub_seize(struct pci_dev *dev) { struct pcistub_device *psdev; @@ -1012,7 +1042,6 @@ static inline int str_to_quirk(const char *buf, int *domain, int *bus, int static int pcistub_device_id_add(int domain, int bus, int slot, int func) { struct pcistub_device_id *pci_dev_id; - unsigned long flags; int rc = 0, devfn = PCI_DEVFN(slot, func); if (slot < 0) { @@ -1042,16 +1071,10 @@ static int pcistub_device_id_add(int domain, int bus, int slot, int func) if (!pci_dev_id) return -ENOMEM; - pci_dev_id->domain = domain; - pci_dev_id->bus = bus; - pci_dev_id->devfn = devfn; - pr_debug("wants to seize %04x:%02x:%02x.%d\n", domain, bus, slot, func); - spin_lock_irqsave(&device_ids_lock, flags); - list_add_tail(&pci_dev_id->slot_list, &pcistub_device_ids); - spin_unlock_irqrestore(&device_ids_lock, flags); + pcistub_device_id_add_list(pci_dev_id, domain, bus, devfn); return 0; } -- 2.6.6