From 589c74d5076dd1bde13a5a36d97ca79be8bd72b2 Mon Sep 17 00:00:00 2001 From: Stefan Haberland Date: Fri, 26 Feb 2010 22:37:47 +0100 Subject: [PATCH] [S390] dasd: fix refcounting. The function dasd_device_from_cdev returns a reference to the dasd device and increases the refcount by one. If an exception occurs, the refcount was not decreased in all cases e.g. in dasd_discipline_show. Prevent the offline processing from hang by correcting two functions to decrease the refcount even if an error occured. Signed-off-by: Stefan Haberland Signed-off-by: Martin Schwidefsky --- drivers/s390/block/dasd.c | 24 +++++++++++++++--------- drivers/s390/block/dasd_devmap.c | 13 ++++++++++--- 2 files changed, 25 insertions(+), 12 deletions(-) diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 56df3c5ed38..302ca14a69e 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -1003,12 +1003,20 @@ static void dasd_handle_killed_request(struct ccw_device *cdev, return; } - device = (struct dasd_device *) cqr->startdev; - if (device == NULL || - device != dasd_device_from_cdev_locked(cdev) || - strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { + device = dasd_device_from_cdev_locked(cdev); + if (IS_ERR(device)) { + DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", + "unable to get device from cdev"); + return; + } + + if (!cqr->startdev || + device != cqr->startdev || + strncmp(cqr->startdev->discipline->ebcname, + (char *) &cqr->magic, 4)) { DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", "invalid device in request"); + dasd_put_device(device); return; } @@ -2291,11 +2299,6 @@ static void dasd_generic_auto_online(void *data, async_cookie_t cookie) if (ret) pr_warning("%s: Setting the DASD online failed with rc=%d\n", dev_name(&cdev->dev), ret); - else { - struct dasd_device *device = dasd_device_from_cdev(cdev); - wait_event(dasd_init_waitq, _wait_for_device(device)); - dasd_put_device(device); - } } /* @@ -2430,6 +2433,9 @@ int dasd_generic_set_online(struct ccw_device *cdev, } else pr_debug("dasd_generic device %s found\n", dev_name(&cdev->dev)); + + wait_event(dasd_init_waitq, _wait_for_device(device)); + dasd_put_device(device); return rc; } diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c index 4cac5b54f26..d49766f3b94 100644 --- a/drivers/s390/block/dasd_devmap.c +++ b/drivers/s390/block/dasd_devmap.c @@ -874,12 +874,19 @@ dasd_discipline_show(struct device *dev, struct device_attribute *attr, ssize_t len; device = dasd_device_from_cdev(to_ccwdev(dev)); - if (!IS_ERR(device) && device->discipline) { + if (IS_ERR(device)) + goto out; + else if (!device->discipline) { + dasd_put_device(device); + goto out; + } else { len = snprintf(buf, PAGE_SIZE, "%s\n", device->discipline->name); dasd_put_device(device); - } else - len = snprintf(buf, PAGE_SIZE, "none\n"); + return len; + } +out: + len = snprintf(buf, PAGE_SIZE, "none\n"); return len; } -- 2.39.5