From patchwork Thu Dec 7 19:34:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Salisbury X-Patchwork-Id: 845789 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 3yt5Jj09qhz9sCZ; Fri, 8 Dec 2017 06:34:13 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1eN1vs-00076W-62; Thu, 07 Dec 2017 19:34:08 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128) (Exim 4.86_2) (envelope-from ) id 1eN1vq-00076K-Lo for kernel-team@lists.ubuntu.com; Thu, 07 Dec 2017 19:34:06 +0000 Received: from 1.general.jsalisbury.us.vpn ([10.172.67.212] helo=salisbury) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1eN1vq-0000uT-9O for kernel-team@lists.ubuntu.com; Thu, 07 Dec 2017 19:34:06 +0000 Received: by salisbury (Postfix, from userid 1000) id 429A87E26C8; Thu, 7 Dec 2017 14:34:05 -0500 (EST) From: Joseph Salisbury To: kernel-team@lists.ubuntu.com Subject: [SRU][Xenial][Artful][Bionic][PATCH 1/1] UBUNTU: SAUCE: (no-up) bcache: decouple emitting a cached_dev CHANGE uevent Date: Thu, 7 Dec 2017 14:34:05 -0500 Message-Id: X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Ryan Harper BugLink: http://bugs.launchpad.net/bugs/1729145 - decouple emitting a cached_dev CHANGE uevent which includes dev.uuid and dev.label from bch_cached_dev_run() which only happens when a bcacheX device is bound to the actual backing block device (bcache0 -> vdb) - update bch_cached_dev_run() to invoke bch_cached_dev_emit_change() as needed; no functional code path changes here - Modify register_bcache to detect a re-registering of a bcache cached_dev, and in that case call bcache_cached_dev_emit_change() to emit the uevent needed to trigger SYMLINK generation Signed-off-by: Ryan Harper Signed-off-by: Joseph Salisbury Reported-by: Ryan Harper Tested-by: Ryan Harper --- drivers/md/bcache/bcache.h | 1 + drivers/md/bcache/super.c | 53 +++++++++++++++++++++++++++++++++++++--------- 2 files changed, 44 insertions(+), 10 deletions(-) diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index 02619ca..8ed7e7a 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -906,6 +906,7 @@ int bch_flash_dev_create(struct cache_set *c, uint64_t size); int bch_cached_dev_attach(struct cached_dev *, struct cache_set *); void bch_cached_dev_detach(struct cached_dev *); +void bch_cached_dev_emit_change(struct cached_dev *); void bch_cached_dev_run(struct cached_dev *); void bcache_device_stop(struct bcache_device *); diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 04608da..9417e15 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -834,7 +834,7 @@ static void calc_cached_dev_sectors(struct cache_set *c) c->cached_dev_sectors = sectors; } -void bch_cached_dev_run(struct cached_dev *dc) +void bch_cached_dev_emit_change(struct cached_dev *dc) { struct bcache_device *d = &dc->disk; char buf[SB_LABEL_SIZE + 1]; @@ -849,9 +849,18 @@ void bch_cached_dev_run(struct cached_dev *dc) buf[SB_LABEL_SIZE] = '\0'; env[2] = kasprintf(GFP_KERNEL, "CACHED_LABEL=%s", buf); + /* won't show up in the uevent file, use udevadm monitor -e instead + * only class / kset properties are persistent */ + kobject_uevent_env(&disk_to_dev(d->disk)->kobj, KOBJ_CHANGE, env); + kfree(env[1]); + kfree(env[2]); + +} + +void bch_cached_dev_run(struct cached_dev *dc) +{ + struct bcache_device *d = &dc->disk; if (atomic_xchg(&dc->running, 1)) { - kfree(env[1]); - kfree(env[2]); return; } @@ -867,11 +876,9 @@ void bch_cached_dev_run(struct cached_dev *dc) add_disk(d->disk); bd_link_disk_holder(dc->bdev, dc->disk.disk); - /* won't show up in the uevent file, use udevadm monitor -e instead - * only class / kset properties are persistent */ - kobject_uevent_env(&disk_to_dev(d->disk)->kobj, KOBJ_CHANGE, env); - kfree(env[1]); - kfree(env[2]); + + /* emit change event */ + bch_cached_dev_emit_change(dc); if (sysfs_create_link(&d->kobj, &disk_to_dev(d->disk)->kobj, "dev") || sysfs_create_link(&disk_to_dev(d->disk)->kobj, &d->kobj, "bcache")) @@ -1916,6 +1923,21 @@ static bool bch_is_open_backing(struct block_device *bdev) { return false; } +static struct cached_dev *bch_find_cached_dev(struct block_device *bdev) { + struct cache_set *c, *tc; + struct cached_dev *dc, *t; + + list_for_each_entry_safe(c, tc, &bch_cache_sets, list) + list_for_each_entry_safe(dc, t, &c->cached_devs, list) + if (dc->bdev == bdev) + return dc; + list_for_each_entry_safe(dc, t, &uncached_devices, list) + if (dc->bdev == bdev) + return dc; + + return NULL; +} + static bool bch_is_open_cache(struct block_device *bdev) { struct cache_set *c, *tc; struct cache *ca; @@ -1941,6 +1963,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, struct cache_sb *sb = NULL; struct block_device *bdev = NULL; struct page *sb_page = NULL; + struct cached_dev *dc = NULL; if (!try_module_get(THIS_MODULE)) return -EBUSY; @@ -1957,10 +1980,20 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr, if (bdev == ERR_PTR(-EBUSY)) { bdev = lookup_bdev(strim(path), 0); mutex_lock(&bch_register_lock); - if (!IS_ERR(bdev) && bch_is_open(bdev)) + if (!IS_ERR(bdev) && bch_is_open(bdev)) { err = "device already registered"; - else + /* emit CHANGE event for backing devices to export + * CACHED_{UUID/LABEL} values to udev */ + if (bch_is_open_backing(bdev)) { + dc = bch_find_cached_dev(bdev); + if (dc) { + bch_cached_dev_emit_change(dc); + err = "device already registered (emitting change event)"; + } + } + } else { err = "device busy"; + } mutex_unlock(&bch_register_lock); if (!IS_ERR(bdev)) bdput(bdev);