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-rw-r--r--drivers/ieee1394/nodemgr.c142
1 files changed, 92 insertions, 50 deletions
diff --git a/drivers/ieee1394/nodemgr.c b/drivers/ieee1394/nodemgr.c
index bffa26e48152..e2ca8e92f43f 100644
--- a/drivers/ieee1394/nodemgr.c
+++ b/drivers/ieee1394/nodemgr.c
@@ -374,11 +374,11 @@ static ssize_t fw_set_ignore_driver(struct device *dev, struct device_attribute
int state = simple_strtoul(buf, NULL, 10);
if (state == 1) {
- down_write(&dev->bus->subsys.rwsem);
- device_release_driver(dev);
ud->ignore_driver = 1;
- up_write(&dev->bus->subsys.rwsem);
- } else if (!state)
+ down_write(&ieee1394_bus_type.subsys.rwsem);
+ device_release_driver(dev);
+ up_write(&ieee1394_bus_type.subsys.rwsem);
+ } else if (state == 0)
ud->ignore_driver = 0;
return count;
@@ -436,7 +436,7 @@ static ssize_t fw_set_ignore_drivers(struct bus_type *bus, const char *buf, size
if (state == 1)
ignore_drivers = 1;
- else if (!state)
+ else if (state == 0)
ignore_drivers = 0;
return count;
@@ -734,20 +734,65 @@ static int nodemgr_bus_match(struct device * dev, struct device_driver * drv)
}
+static DEFINE_MUTEX(nodemgr_serialize_remove_uds);
+
static void nodemgr_remove_uds(struct node_entry *ne)
{
- struct class_device *cdev, *next;
- struct unit_directory *ud;
+ struct class_device *cdev;
+ struct unit_directory *ud, **unreg;
+ size_t i, count;
+
+ /*
+ * This is awkward:
+ * Iteration over nodemgr_ud_class.children has to be protected by
+ * nodemgr_ud_class.sem, but class_device_unregister() will eventually
+ * take nodemgr_ud_class.sem too. Therefore store all uds to be
+ * unregistered in a temporary array, release the semaphore, and then
+ * unregister the uds.
+ *
+ * Since nodemgr_remove_uds can also run in other contexts than the
+ * knodemgrds (which are currently globally serialized), protect the
+ * gap after release of the semaphore by nodemgr_serialize_remove_uds.
+ */
- list_for_each_entry_safe(cdev, next, &nodemgr_ud_class.children, node) {
- ud = container_of(cdev, struct unit_directory, class_dev);
+ mutex_lock(&nodemgr_serialize_remove_uds);
- if (ud->ne != ne)
- continue;
+ down(&nodemgr_ud_class.sem);
+ count = 0;
+ list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
+ ud = container_of(cdev, struct unit_directory, class_dev);
+ if (ud->ne == ne)
+ count++;
+ }
+ if (!count) {
+ up(&nodemgr_ud_class.sem);
+ mutex_unlock(&nodemgr_serialize_remove_uds);
+ return;
+ }
+ unreg = kcalloc(count, sizeof(*unreg), GFP_KERNEL);
+ if (!unreg) {
+ HPSB_ERR("NodeMgr: out of memory in nodemgr_remove_uds");
+ up(&nodemgr_ud_class.sem);
+ mutex_unlock(&nodemgr_serialize_remove_uds);
+ return;
+ }
+ i = 0;
+ list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
+ ud = container_of(cdev, struct unit_directory, class_dev);
+ if (ud->ne == ne) {
+ BUG_ON(i >= count);
+ unreg[i++] = ud;
+ }
+ }
+ up(&nodemgr_ud_class.sem);
- class_device_unregister(&ud->class_dev);
- device_unregister(&ud->device);
+ for (i = 0; i < count; i++) {
+ class_device_unregister(&unreg[i]->class_dev);
+ device_unregister(&unreg[i]->device);
}
+ kfree(unreg);
+
+ mutex_unlock(&nodemgr_serialize_remove_uds);
}
@@ -880,12 +925,11 @@ fail_alloc:
static struct node_entry *find_entry_by_guid(u64 guid)
{
- struct class *class = &nodemgr_ne_class;
struct class_device *cdev;
struct node_entry *ne, *ret_ne = NULL;
- down_read(&class->subsys.rwsem);
- list_for_each_entry(cdev, &class->children, node) {
+ down(&nodemgr_ne_class.sem);
+ list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
ne = container_of(cdev, struct node_entry, class_dev);
if (ne->guid == guid) {
@@ -893,20 +937,20 @@ static struct node_entry *find_entry_by_guid(u64 guid)
break;
}
}
- up_read(&class->subsys.rwsem);
+ up(&nodemgr_ne_class.sem);
return ret_ne;
}
-static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host, nodeid_t nodeid)
+static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host,
+ nodeid_t nodeid)
{
- struct class *class = &nodemgr_ne_class;
struct class_device *cdev;
struct node_entry *ne, *ret_ne = NULL;
- down_read(&class->subsys.rwsem);
- list_for_each_entry(cdev, &class->children, node) {
+ down(&nodemgr_ne_class.sem);
+ list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
ne = container_of(cdev, struct node_entry, class_dev);
if (ne->host == host && ne->nodeid == nodeid) {
@@ -914,7 +958,7 @@ static struct node_entry *find_entry_by_nodeid(struct hpsb_host *host, nodeid_t
break;
}
}
- up_read(&class->subsys.rwsem);
+ up(&nodemgr_ne_class.sem);
return ret_ne;
}
@@ -1377,7 +1421,6 @@ static void nodemgr_node_scan(struct host_info *hi, int generation)
}
-/* Caller needs to hold nodemgr_ud_class.subsys.rwsem as reader. */
static void nodemgr_suspend_ne(struct node_entry *ne)
{
struct class_device *cdev;
@@ -1389,19 +1432,20 @@ static void nodemgr_suspend_ne(struct node_entry *ne)
ne->in_limbo = 1;
WARN_ON(device_create_file(&ne->device, &dev_attr_ne_in_limbo));
- down_write(&ne->device.bus->subsys.rwsem);
+ down(&nodemgr_ud_class.sem);
list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
ud = container_of(cdev, struct unit_directory, class_dev);
-
if (ud->ne != ne)
continue;
+ down_write(&ieee1394_bus_type.subsys.rwsem);
if (ud->device.driver &&
(!ud->device.driver->suspend ||
ud->device.driver->suspend(&ud->device, PMSG_SUSPEND)))
device_release_driver(&ud->device);
+ up_write(&ieee1394_bus_type.subsys.rwsem);
}
- up_write(&ne->device.bus->subsys.rwsem);
+ up(&nodemgr_ud_class.sem);
}
@@ -1413,45 +1457,47 @@ static void nodemgr_resume_ne(struct node_entry *ne)
ne->in_limbo = 0;
device_remove_file(&ne->device, &dev_attr_ne_in_limbo);
- down_read(&nodemgr_ud_class.subsys.rwsem);
- down_read(&ne->device.bus->subsys.rwsem);
+ down(&nodemgr_ud_class.sem);
list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
ud = container_of(cdev, struct unit_directory, class_dev);
-
if (ud->ne != ne)
continue;
+ down_read(&ieee1394_bus_type.subsys.rwsem);
if (ud->device.driver && ud->device.driver->resume)
ud->device.driver->resume(&ud->device);
+ up_read(&ieee1394_bus_type.subsys.rwsem);
}
- up_read(&ne->device.bus->subsys.rwsem);
- up_read(&nodemgr_ud_class.subsys.rwsem);
+ up(&nodemgr_ud_class.sem);
HPSB_DEBUG("Node resumed: ID:BUS[" NODE_BUS_FMT "] GUID[%016Lx]",
NODE_BUS_ARGS(ne->host, ne->nodeid), (unsigned long long)ne->guid);
}
-/* Caller needs to hold nodemgr_ud_class.subsys.rwsem as reader. */
static void nodemgr_update_pdrv(struct node_entry *ne)
{
struct unit_directory *ud;
struct hpsb_protocol_driver *pdrv;
struct class_device *cdev;
+ down(&nodemgr_ud_class.sem);
list_for_each_entry(cdev, &nodemgr_ud_class.children, node) {
ud = container_of(cdev, struct unit_directory, class_dev);
- if (ud->ne != ne || !ud->device.driver)
+ if (ud->ne != ne)
continue;
- pdrv = container_of(ud->device.driver, struct hpsb_protocol_driver, driver);
-
- if (pdrv->update && pdrv->update(ud)) {
- down_write(&ud->device.bus->subsys.rwsem);
- device_release_driver(&ud->device);
- up_write(&ud->device.bus->subsys.rwsem);
+ down_write(&ieee1394_bus_type.subsys.rwsem);
+ if (ud->device.driver) {
+ pdrv = container_of(ud->device.driver,
+ struct hpsb_protocol_driver,
+ driver);
+ if (pdrv->update && pdrv->update(ud))
+ device_release_driver(&ud->device);
}
+ up_write(&ieee1394_bus_type.subsys.rwsem);
}
+ up(&nodemgr_ud_class.sem);
}
@@ -1482,8 +1528,6 @@ static void nodemgr_irm_write_bc(struct node_entry *ne, int generation)
}
-/* Caller needs to hold nodemgr_ud_class.subsys.rwsem as reader because the
- * calls to nodemgr_update_pdrv() and nodemgr_suspend_ne() here require it. */
static void nodemgr_probe_ne(struct host_info *hi, struct node_entry *ne, int generation)
{
struct device *dev;
@@ -1516,7 +1560,6 @@ static void nodemgr_probe_ne(struct host_info *hi, struct node_entry *ne, int ge
static void nodemgr_node_probe(struct host_info *hi, int generation)
{
struct hpsb_host *host = hi->host;
- struct class *class = &nodemgr_ne_class;
struct class_device *cdev;
struct node_entry *ne;
@@ -1529,18 +1572,18 @@ static void nodemgr_node_probe(struct host_info *hi, int generation)
* while probes are time-consuming. (Well, those probes need some
* improvement...) */
- down_read(&class->subsys.rwsem);
- list_for_each_entry(cdev, &class->children, node) {
+ down(&nodemgr_ne_class.sem);
+ list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
ne = container_of(cdev, struct node_entry, class_dev);
if (!ne->needs_probe)
nodemgr_probe_ne(hi, ne, generation);
}
- list_for_each_entry(cdev, &class->children, node) {
+ list_for_each_entry(cdev, &nodemgr_ne_class.children, node) {
ne = container_of(cdev, struct node_entry, class_dev);
if (ne->needs_probe)
nodemgr_probe_ne(hi, ne, generation);
}
- up_read(&class->subsys.rwsem);
+ up(&nodemgr_ne_class.sem);
/* If we had a bus reset while we were scanning the bus, it is
@@ -1752,19 +1795,18 @@ exit:
int nodemgr_for_each_host(void *__data, int (*cb)(struct hpsb_host *, void *))
{
- struct class *class = &hpsb_host_class;
struct class_device *cdev;
struct hpsb_host *host;
int error = 0;
- down_read(&class->subsys.rwsem);
- list_for_each_entry(cdev, &class->children, node) {
+ down(&hpsb_host_class.sem);
+ list_for_each_entry(cdev, &hpsb_host_class.children, node) {
host = container_of(cdev, struct hpsb_host, class_dev);
if ((error = cb(host, __data)))
break;
}
- up_read(&class->subsys.rwsem);
+ up(&hpsb_host_class.sem);
return error;
}
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