Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161053AbXBTW5e (ORCPT ); Tue, 20 Feb 2007 17:57:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161051AbXBTW5d (ORCPT ); Tue, 20 Feb 2007 17:57:33 -0500 Received: from mtagate2.de.ibm.com ([195.212.29.151]:47344 "EHLO mtagate2.de.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161065AbXBTW5c (ORCPT ); Tue, 20 Feb 2007 17:57:32 -0500 From: Hoang-Nam Nguyen To: paulus@samba.org, linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, johnrose@us.ibm.com Subject: [PATCH 2.6.21-rc1] ibmebus: more error reporting in dynamic add/remove code User-Agent: KMail/1.8.2 Cc: pmac@au1.ibm.com, fenkes@de.ibm.com MIME-Version: 1.0 Content-Disposition: inline Date: Wed, 21 Feb 2007 00:01:21 +0100 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200702210001.21273.hnguyen@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5045 Lines: 165 Writing the ibmebus probe and remove attributes now throws an appropriate error if something goes wrong. This way, userspace tools can check for success or failure of an addition or removal. The write will block until the probe/remove operation completes, so, when the write operation returns without an error, you can be sure the probe was successful and the device is present in the system. As an added bonus, an eventual trailing newline is now removed from the written string. Signed-off-by: Joachim Fenkes --- ibmebus.c | 54 ++++++++++++++++++++++++++++++++++++------------------ 1 files changed, 36 insertions(+), 18 deletions(-) diff -urp a/arch/powerpc/kernel/ibmebus.c b/arch/powerpc/kernel/ibmebus.c --- a/arch/powerpc/kernel/ibmebus.c 2007-02-20 21:54:22.366443424 +0100 +++ b/arch/powerpc/kernel/ibmebus.c 2007-02-20 23:31:39.950486616 +0100 @@ -167,7 +167,7 @@ static ssize_t ibmebusdev_show_name(stru static DEVICE_ATTR(name, S_IRUSR | S_IRGRP | S_IROTH, ibmebusdev_show_name, NULL); -static struct ibmebus_dev* __devinit ibmebus_register_device_common( +static int __devinit ibmebus_register_device_common( struct ibmebus_dev *dev, const char *name) { int err = 0; @@ -186,12 +186,12 @@ static struct ibmebus_dev* __devinit ibm if ((err = of_device_register(&dev->ofdev)) != 0) { printk(KERN_ERR "%s: failed to register device (%d).\n", __FUNCTION__, err); - return NULL; + return -ENODEV; } device_create_file(&dev->ofdev.dev, &dev_attr_name); - return dev; + return 0; } static struct ibmebus_dev* __devinit ibmebus_register_device_node( @@ -205,18 +205,18 @@ static struct ibmebus_dev* __devinit ibm if (!loc_code) { printk(KERN_WARNING "%s: node %s missing 'ibm,loc-code'\n", __FUNCTION__, dn->name ? dn->name : ""); - return NULL; + return ERR_PTR(-EINVAL); } if (strlen(loc_code) == 0) { printk(KERN_WARNING "%s: 'ibm,loc-code' is invalid\n", __FUNCTION__); - return NULL; + return ERR_PTR(-EINVAL); } dev = kzalloc(sizeof(struct ibmebus_dev), GFP_KERNEL); if (!dev) { - return NULL; + return ERR_PTR(-ENOMEM); } dev->ofdev.node = of_node_get(dn); @@ -227,9 +227,9 @@ static struct ibmebus_dev* __devinit ibm min(length, BUS_ID_SIZE - 1)); /* Register with generic device framework. */ - if (ibmebus_register_device_common(dev, dn->name) == NULL) { + if (ibmebus_register_device_common(dev, dn->name) != 0) { kfree(dev); - return NULL; + return ERR_PTR(-ENODEV); } return dev; @@ -240,9 +240,8 @@ static void ibmebus_probe_of_nodes(char* struct device_node *dn = NULL; while ((dn = of_find_node_by_name(dn, name))) { - if (ibmebus_register_device_node(dn) == NULL) { + if (IS_ERR(ibmebus_register_device_node(dn))) { of_node_put(dn); - return; } } @@ -390,30 +389,40 @@ static int ibmebus_match_helper_loc_code return 0; } -static ssize_t ibmebus_store_probe(struct bus_type *dev, +static ssize_t ibmebus_store_probe(struct bus_type *bus, const char *buf, size_t count) { struct device_node *dn = NULL; + struct ibmebus_dev *dev; char *loc_code; + buf[count] = '\0'; + if (buf[count-1] == '\n') + buf[count-1] = '\0'; + if (bus_find_device(&ibmebus_bus_type, NULL, (char*)buf, ibmebus_match_helper_loc_code)) { printk(KERN_WARNING "%s: loc_code %s has already been probed\n", __FUNCTION__, buf); - return count; + return -EINVAL; } while ((dn = of_find_all_nodes(dn))) { loc_code = (char *)get_property(dn, "ibm,loc-code", NULL); if (loc_code && (strncmp(loc_code, buf, count) == 0)) { - if (ibmebus_register_device_node(dn) == NULL) { + dev = ibmebus_register_device_node(dn); + if (IS_ERR(dev)) { of_node_put(dn); - break; - } + return PTR_ERR(dev); + } else + return count; /* success */ } } - return count; + /* if we drop out of the loop, the loc code was invalid */ + printk(KERN_WARNING "%s: no device with loc_code %s found\n", + __FUNCTION__, buf); + return -ENODEV; } static BUS_ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe); @@ -422,9 +431,18 @@ static ssize_t ibmebus_store_remove(stru { struct device *dev; - while ((dev = bus_find_device(&ibmebus_bus_type, NULL, (char*)buf, - ibmebus_match_helper_loc_code))) { + buf[count] = '\0'; + if (buf[count-1] == '\n') + buf[count-1] = '\0'; + + /* The location code is unique, so we will find one device at most */ + if ((dev = bus_find_device(&ibmebus_bus_type, NULL, (char*)buf, + ibmebus_match_helper_loc_code))) { ibmebus_unregister_device(dev); + } else { + printk(KERN_WARNING "%s: loc_code %s not on the bus\n", + __FUNCTION__, buf); + return -ENODEV; } return count; - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/