[patch 05/12] Take the PCI lock when modifying pci bus or device lists

Rajesh Shah
2005-03-18T22:07:06Z

With root bridge and pci bridge hot-plug, new buses and devices
can be added or removed at run time. Protect the pci bus and
device lists with the pci lock when doing so.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
---

linux-2.6.11-mm4-iohp-rshah1/drivers/pci/probe.c | 12 +++++++++++-
1 files changed, 11 insertions(+), 1 deletion(-)

diff -puN drivers/pci/probe.c~lock-pci-root-bus-add drivers/pci/probe.c
--- linux-2.6.11-mm4-iohp/drivers/pci/probe.c~lock-pci-root-bus-add 2005-03-16 13:07:14.694663612 -0800
+++ linux-2.6.11-mm4-iohp-rshah1/drivers/pci/probe.c 2005-03-16 13:07:14.802085486 -0800
@@ -8,6 +8,7 @@
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/cpumask.h>
+#include "pci.h"

#undef DEBUG

@@ -380,8 +381,11 @@ struct pci_bus * __devinit pci_add_new_b
struct pci_bus *child;

child = pci_alloc_child_bus(parent, dev, busnr);
- if (child)
+ if (child) {
+ spin_lock(&pci_bus_lock);
list_add_tail(&child->node, &parent->children);
+ spin_unlock(&pci_bus_lock);
+ }
return child;
}

@@ -771,7 +775,9 @@ pci_scan_single_device(struct pci_bus *b
* and the bus list for fixup functions, etc.
*/
INIT_LIST_HEAD(&dev->global_list);
+ spin_lock(&pci_bus_lock);
list_add_tail(&dev->bus_list, &bus->devices);
+ spin_unlock(&pci_bus_lock);

return dev;
}
@@ -891,7 +897,9 @@ struct pci_bus * __devinit pci_scan_bus_
DBG("PCI: Bus %04x:%02x already known\n", pci_domain_nr(b), bus);
goto err_out;
}
+ spin_lock(&pci_bus_lock);
list_add_tail(&b->node, &pci_root_buses);
+ spin_unlock(&pci_bus_lock);

memset(dev, 0, sizeof(*dev));
dev->parent = parent;
@@ -933,7 +941,9 @@ class_dev_create_file_err:
class_dev_reg_err:
device_unregister(dev);
dev_reg_err:
+ spin_lock(&pci_bus_lock);
list_del(&b->node);
+ spin_unlock(&pci_bus_lock);
err_out:
kfree(dev);
kfree(b);
_