[PATCH] Lastminute IEEE-1394 fixes

I've got a lot more changes than what's included here.  I've put this
down to the bear minimum to get things working sanely.

Mainly, I just want to get all the people hit by this a chance to use
2.6.0 without having to get our tree. Changes itemized:

 - Fix deadlock possibility in csr.c:read_maps()
 - Fix kmalloc to use ATOMIC in highlevel.c.
 - s/in_interrupt/irqs_disabled/ in ieee1394_transactions.c to fix
   warnings when transactions occured.
 - Introduce a release callback for the host driver and use it correctly.
 - Reorganize the nodemgr probe so we do an initial scan to discover
   devices, check IRM/CycleMaster, then do a final full probe when things
   are kosher. Fixes a problem where device registration and hotplug
   would cause some serious problems when a bus reset was forced in the
   middle of the probe.

drivers/ieee1394/csr.c

@@ -202,6 +202,7 @@ static int read_maps(struct hpsb_host *host, int nodeid, quadlet_t *buffer,
 
         if (csraddr < CSR_TOPOLOGY_MAP) {
                 if (csraddr + length > CSR_CONFIG_ROM + host->csr.rom_size) {
+                        spin_unlock_irqrestore(&host->csr.lock, flags);
                         return RCODE_ADDRESS_ERROR;
                 }
                 src = ((char *)host->csr.rom) + csraddr - CSR_CONFIG_ROM;

drivers/ieee1394/highlevel.c

@@ -98,7 +98,7 @@ void *hpsb_create_hostinfo(struct hpsb_highlevel *hl, struct hpsb_host *host,
 		return NULL;
 	}
 
-	hi = kmalloc(sizeof(*hi) + data_size, GFP_KERNEL);
+	hi = kmalloc(sizeof(*hi) + data_size, GFP_ATOMIC);
 	if (!hi)
 		return NULL;
 

drivers/ieee1394/hosts.c

@@ -92,7 +92,7 @@ void hpsb_unref_host(struct hpsb_host *host)
 
 	down(&hpsb_hosts_lock);
         if (atomic_dec_and_test(&host->refcount) && host->is_shutdown)
-                kfree(host);
+		device_unregister(&host->device);
 	up(&hpsb_hosts_lock);
 }
 

drivers/ieee1394/ieee1394_transactions.c

@@ -137,7 +137,7 @@ int hpsb_get_tlabel(struct hpsb_packet *packet)
 
 	tp = &packet->host->tpool[packet->node_id & NODE_MASK];
 
-	if (in_interrupt() || in_atomic()) {
+	if (irqs_disabled() || in_atomic()) {
 		if (down_trylock(&tp->count))
 			return 1;
 	} else {

drivers/ieee1394/ieee1394_types.h

@@ -13,9 +13,6 @@
 #include <asm/byteorder.h>
 
 
-/* The great kdev_t changeover in 2.5.x */
-#include <linux/kdev_t.h>
-
 /* Transaction Label handling */
 struct hpsb_tlabel_pool {
 	DECLARE_BITMAP(pool, 64);

drivers/ieee1394/nodemgr.c

@@ -420,6 +420,12 @@ static void nodemgr_release_ne(struct device *dev)
 }
 
 
+static void nodemgr_release_host(struct device *dev)
+{
+	kfree(container_of(dev, struct hpsb_host, device));
+}
+
+
 static void nodemgr_remove_ud(struct unit_directory *ud)
 {
 	struct device *dev = &ud->device;
@@ -513,6 +519,7 @@ static struct device nodemgr_dev_template_ne = {
 
 static struct device nodemgr_dev_template_host = {
 	.bus		= &ieee1394_bus_type,
+	.release	= nodemgr_release_host,
 	.driver		= &nodemgr_driver_host,
 	.driver_data	= &nodemgr_driverdata_host,
 };
@@ -676,8 +683,27 @@ static struct node_entry *nodemgr_scan_root_directory
 }
 
 
-static void nodemgr_process_config_rom(struct host_info *hi,
-		struct node_entry *ne, quadlet_t busoptions);
+static void nodemgr_update_bus_options(struct node_entry *ne,
+                                       quadlet_t busoptions)
+{
+	ne->busopt.irmc         = (busoptions >> 31) & 1;
+	ne->busopt.cmc          = (busoptions >> 30) & 1;
+	ne->busopt.isc          = (busoptions >> 29) & 1;
+	ne->busopt.bmc          = (busoptions >> 28) & 1;
+	ne->busopt.pmc          = (busoptions >> 27) & 1;
+	ne->busopt.cyc_clk_acc  = (busoptions >> 16) & 0xff;
+	ne->busopt.max_rec      = 1 << (((busoptions >> 12) & 0xf) + 1);
+	ne->busopt.generation   = (busoptions >> 4) & 0xf;
+	ne->busopt.lnkspd       = busoptions & 0x7;
+	
+	HPSB_VERBOSE("NodeMgr: raw=0x%08x irmc=%d cmc=%d isc=%d bmc=%d pmc=%d "
+		     "cyc_clk_acc=%d max_rec=%d gen=%d lspd=%d",
+		     busoptions, ne->busopt.irmc, ne->busopt.cmc,
+		     ne->busopt.isc, ne->busopt.bmc, ne->busopt.pmc,
+		     ne->busopt.cyc_clk_acc, ne->busopt.max_rec,
+		     ne->busopt.generation, ne->busopt.lnkspd);
+}
+
 
 static struct node_entry *nodemgr_create_node(octlet_t guid, quadlet_t busoptions,
 					      struct host_info *hi, nodeid_t nodeid,
@@ -694,6 +720,7 @@ static struct node_entry *nodemgr_create_node(octlet_t guid, quadlet_t busoption
         ne->host = host;
         ne->nodeid = nodeid;
 	ne->generation = generation;
+	ne->needs_probe = 1;
 
         ne->guid = guid;
 	ne->guid_vendor_id = (guid >> 40) & 0xffffff;
@@ -711,7 +738,7 @@ static struct node_entry *nodemgr_create_node(octlet_t guid, quadlet_t busoption
 		device_create_file(&ne->device, &dev_attr_ne_guid_vendor_oui);
 	nodemgr_create_ne_dev_files(ne);
 
-	nodemgr_process_config_rom (hi, ne, busoptions);
+	nodemgr_update_bus_options(ne, busoptions);
 
 	HPSB_DEBUG("%s added: ID:BUS[" NODE_BUS_FMT "]  GUID[%016Lx]",
 		   (host->node_id == nodeid) ? "Host" : "Node",
@@ -806,6 +833,7 @@ static struct unit_directory *nodemgr_scan_unit_directory
 
 	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation, address, &quad))
 		return NULL;
+
 	length = CONFIG_ROM_DIRECTORY_LENGTH(quad) ;
 	address += 4;
 
@@ -1069,6 +1097,8 @@ static void nodemgr_process_root_directory(struct host_info *hi, struct node_ent
 	int length;
 	unsigned int ud_id = 0;
 
+	device_remove_file(&ne->device, &dev_attr_ne_vendor_oui);
+
 	address = CSR_REGISTER_BASE + CSR_CONFIG_ROM;
 	
 	if (nodemgr_read_quadlet(ne->host, ne->nodeid, ne->generation,
@@ -1129,6 +1159,9 @@ static void nodemgr_process_root_directory(struct host_info *hi, struct node_ent
 			break;
 		}
 	}
+
+	if (ne->vendor_oui)
+		device_create_file(&ne->device, &dev_attr_ne_vendor_oui);
 }
 
 #ifdef CONFIG_HOTPLUG
@@ -1221,34 +1254,6 @@ void hpsb_unregister_protocol(struct hpsb_protocol_driver *driver)
 	driver_unregister(&driver->driver);
 }
 
-static void nodemgr_process_config_rom(struct host_info *hi,
-		struct node_entry *ne, quadlet_t busoptions)
-{
-	ne->busopt.irmc		= (busoptions >> 31) & 1;
-	ne->busopt.cmc		= (busoptions >> 30) & 1;
-	ne->busopt.isc		= (busoptions >> 29) & 1;
-	ne->busopt.bmc		= (busoptions >> 28) & 1;
-	ne->busopt.pmc		= (busoptions >> 27) & 1;
-	ne->busopt.cyc_clk_acc	= (busoptions >> 16) & 0xff;
-	ne->busopt.max_rec	= 1 << (((busoptions >> 12) & 0xf) + 1);
-	ne->busopt.generation	= (busoptions >> 4) & 0xf;
-	ne->busopt.lnkspd	= busoptions & 0x7;
-
-	HPSB_VERBOSE("NodeMgr: raw=0x%08x irmc=%d cmc=%d isc=%d bmc=%d pmc=%d "
-		     "cyc_clk_acc=%d max_rec=%d gen=%d lspd=%d",
-		     busoptions, ne->busopt.irmc, ne->busopt.cmc,
-		     ne->busopt.isc, ne->busopt.bmc, ne->busopt.pmc,
-		     ne->busopt.cyc_clk_acc, ne->busopt.max_rec,
-		     ne->busopt.generation, ne->busopt.lnkspd);
-
-	device_remove_file(&ne->device, &dev_attr_ne_vendor_oui);
-
-	nodemgr_process_root_directory(hi, ne);
-
-	if (ne->vendor_oui)
-		device_create_file(&ne->device, &dev_attr_ne_vendor_oui);
-}
-
 
 /* Searches the list of ud's that match a ne as the parent. If the ud has
  * a driver associated with it, we call that driver's update function
@@ -1303,18 +1308,14 @@ static void nodemgr_update_node(struct node_entry *ne, quadlet_t busoptions,
 		 * unregister all the unit directories. */
 		nodemgr_remove_node_uds(ne);
 
-		/* With all the ud's gone, mark the generation current,
-		 * this way the probe will succeed. */
-		ne->generation = generation;
+		nodemgr_update_bus_options(ne, busoptions);
 
-		/* This will re-register our unitdir's */
-		nodemgr_process_config_rom (hi, ne, busoptions);
-	} else
-		ne->generation = generation;
+		/* Mark the node as new, so it gets re-probed */
+		ne->needs_probe = 1;
+	}
 
-	/* Update unit_dirs with attached drivers */
-	bus_for_each_dev(&ieee1394_bus_type, NULL, ne,
-			 nodemgr_driver_search_cb);
+	/* Mark the node current */
+	ne->generation = generation;
 }
 
 static int read_businfo_block(struct hpsb_host *host, nodeid_t nodeid, unsigned int generation,
@@ -1385,9 +1386,7 @@ static int read_businfo_block(struct hpsb_host *host, nodeid_t nodeid, unsigned
 }		
 
 
-/* This is where we probe the nodes for their information and provided
- * features.  */
-static void nodemgr_node_probe_one(struct host_info *hi,
+static void nodemgr_node_scan_one(struct host_info *hi,
 				  nodeid_t nodeid, int generation)
 {
 	struct hpsb_host *host = hi->host;
@@ -1453,8 +1452,43 @@ static int nodemgr_remove_node(struct device *dev, void *__data)
 	return 0;
 }
 
+struct ne_cb_data_struct {
+	struct host_info *hi;
+	struct node_entry *ne;
+};
 
-static void nodemgr_node_probe(struct host_info *hi, int generation)
+static int nodemgr_probe_ne_cb(struct device *dev, void *__data)
+{
+	struct ne_cb_data_struct *ne_cb_data = __data;
+	struct host_info *hi = ne_cb_data->hi;
+	struct node_entry *ne;
+
+	if (dev->driver_data != &nodemgr_driverdata_ne)
+		return 0;
+
+	ne = ne_cb_data->ne = container_of(dev, struct node_entry, device);
+
+	if (ne->host != hi->host)
+		return 0;
+
+	/* We can't call nodemgr_process_root_directory() here because
+	 * that can call device_register. Since this callback is under a
+	 * rwsem, the device_register would deadlock. So, we signal back
+	 * to the callback, and process things there. */
+
+	if (ne->needs_probe) {
+		ne->needs_probe = 0;
+		return 1;
+	} else {
+		/* Update unit_dirs with attached drivers */
+		bus_for_each_dev(&ieee1394_bus_type, NULL, ne,
+				 nodemgr_driver_search_cb);
+	}
+	return 0;
+}
+
+
+static void nodemgr_node_scan(struct host_info *hi, int generation)
 {
         int count;
         struct hpsb_host *host = hi->host;
@@ -1470,7 +1504,32 @@ static void nodemgr_node_probe(struct host_info *hi, int generation)
                         nodeid++;
                         continue;
                 }
-		nodemgr_node_probe_one(hi, nodeid++, generation);
+                nodemgr_node_scan_one(hi, nodeid++, generation);
+        }
+}
+
+static void nodemgr_node_probe(struct host_info *hi, int generation)
+{
+	struct hpsb_host *host = hi->host;
+	struct ne_cb_data_struct ne_cb_data;
+
+	ne_cb_data.hi = hi;
+	ne_cb_data.ne = NULL;
+
+	/* Do some processing of the nodes we've probed. This pulls them
+	 * into the sysfs layer if needed, and can result in processing of
+	 * unit-directories, or just updating the node and it's
+	 * unit-directories. */
+	while (bus_for_each_dev(&ieee1394_bus_type, ne_cb_data.ne ? &ne_cb_data.ne->device : NULL,
+	       &ne_cb_data, nodemgr_probe_ne_cb)) {
+		/* If we get in here, we've got a node that needs it's
+		 * unit directories processed. */
+		struct device *dev = get_device(&ne_cb_data.ne->device);
+
+		if (dev) {
+			nodemgr_process_root_directory(hi, ne_cb_data.ne);
+			put_device(dev);
+		}
 	}
 
 	/* If we had a bus reset while we were scanning the bus, it is
@@ -1513,12 +1572,12 @@ static void nodemgr_node_probe(struct host_info *hi, int generation)
 /* Because we are a 1394a-2000 compliant IRM, we need to inform all the other
  * nodes of the broadcast channel.  (Really we're only setting the validity
  * bit). Other IRM responsibilities go in here as well. */
-static void nodemgr_do_irm_duties(struct hpsb_host *host)
+static int nodemgr_do_irm_duties(struct hpsb_host *host, int cycles)
 {
 	quadlet_t bc;
         
 	if (!host->is_irm)
-		return;
+		return 1;
 
 	host->csr.broadcast_channel |= 0x40000000;  /* set validity bit */
 
@@ -1541,10 +1600,21 @@ static void nodemgr_do_irm_duties(struct hpsb_host *host)
 		else {
 			HPSB_DEBUG("The root node is not cycle master capable; "
 				   "selecting a new root node and resetting...");
+
+			if (cycles >= 5) {
+				/* Oh screw it! Just leave the bus as it is */
+				HPSB_DEBUG("Stopping reset loop for IRM sanity");
+				return 1;
+			}
+
 			hpsb_send_phy_config(host, NODEID_TO_NODE(host->node_id), -1);
 			hpsb_reset_bus(host, LONG_RESET_FORCE_ROOT);
+
+			return 0;
 		}
 	}
+
+	return 1;
 }
 
 /* We need to ensure that if we are not the IRM, that the IRM node is capable of
@@ -1608,8 +1678,10 @@ static int nodemgr_host_thread(void *__hi)
 		 * to make sure things settle down. */
 		for (i = 0; i < 4 ; i++) {
 			set_current_state(TASK_INTERRUPTIBLE);
-			if (schedule_timeout(HZ/16))
+			if (schedule_timeout(HZ/16)) {
+				up(&nodemgr_serialize);
 				goto caught_signal;
+			}
 
 			/* Now get the generation in which the node ID's we collect
 			 * are valid.  During the bus scan we will use this generation
@@ -1624,16 +1696,28 @@ static int nodemgr_host_thread(void *__hi)
 				i = 0;
 		}
 
-		if (!nodemgr_check_irm_capability(host, reset_cycles++)) {
-			/* Do nothing, we are resetting */
+		if (!nodemgr_check_irm_capability(host, reset_cycles)) {
+			reset_cycles++;
+			up(&nodemgr_serialize);
+			continue;
+		}
+
+		/* Scan our nodes to get the bus options and create node
+		 * entries. This does not do the sysfs stuff, since that
+		 * would trigger hotplug callbacks and such, which is a
+		 * bad idea at this point. */
+		nodemgr_node_scan(hi, generation);
+		if (!nodemgr_do_irm_duties(host, reset_cycles)) {
+			reset_cycles++;
 			up(&nodemgr_serialize);
 			continue;
 		}
 
 		reset_cycles = 0;
 
+		/* This actually does the full probe, with sysfs
+		 * registration. */
 		nodemgr_node_probe(hi, generation);
-		nodemgr_do_irm_duties(host);
 
 		/* Update some of our sysfs symlinks */
 		nodemgr_update_host_dev_links(host);
@@ -1778,7 +1862,6 @@ static void nodemgr_remove_host(struct hpsb_host *host)
 			kill_proc(hi->pid, SIGTERM, 1);
 			wait_for_completion(&hi->exited);
 			nodemgr_remove_host_dev(&host->device);
-			device_unregister(&host->device);
 		}
 	} else
 		HPSB_ERR("NodeMgr: host %s does not exist, cannot remove",

drivers/ieee1394/nodemgr.h

@@ -130,6 +130,7 @@ struct node_entry {
 	struct hpsb_host *host;		/* Host this node is attached to */
 	nodeid_t nodeid;		/* NodeID */
 	struct bus_options busopt;	/* Bus Options */
+	int needs_probe;
 	unsigned int generation;	/* Synced with hpsb generation */
 
 	/* The following is read from the config rom */