From patchwork Sat Jan 23 00:19:38 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 43549 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from bombadil.infradead.org (bombadil.infradead.org [18.85.46.34]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 5D064B7CB8 for ; Sat, 23 Jan 2010 11:22:29 +1100 (EST) Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) id 1NYTjC-0003PS-MJ; Sat, 23 Jan 2010 00:19:50 +0000 Received: from mail-bw0-f212.google.com ([209.85.218.212]) by bombadil.infradead.org with esmtp (Exim 4.69 #1 (Red Hat Linux)) id 1NYTj5-0003Nu-BD for linux-mtd@lists.infradead.org; Sat, 23 Jan 2010 00:19:48 +0000 Received: by bwz4 with SMTP id 4so1644725bwz.2 for ; Fri, 22 Jan 2010 16:19:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:subject:from:to:cc :in-reply-to:references:content-type:date:message-id:mime-version :x-mailer:content-transfer-encoding; bh=eMpsTh/XoCcczsooUNLBiHJjRC7rpWaKPLugXah5A3w=; b=eNdf7dmAX8bSIciJgZOwDOYFYTckBoERAt7bAKzkGtJwH4OVXhdK54zpaRrhCaEkA+ 1aph4ZOIdObMoExvBNfiNx4F3sdW3dvaR2lHhGUxri+/lu7mfMBJN7x8fLc52sC7GYrz uNvz6whNYzq5L1omrJdSio76/mf2LVEKmjL0A= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=rjb7JovJaOvlCBfArfWRCuL//cr4xkOgpx85UVVQjfvNVXgzmQ0OMWhmWKKwdaTWbn gLYqc0RHy02mnMTWR8G9TYLMNu1cdRi2H1pHpWGUdivGQD5JpA0IJ949aT80FovJoRL4 BMQ42gcfsfG2+tuDm0Vo0/50GsrE2YCasucaY= Received: by 10.204.156.27 with SMTP id u27mr2059537bkw.61.1264205982579; Fri, 22 Jan 2010 16:19:42 -0800 (PST) Received: from ?10.1.0.2? ([87.70.246.165]) by mx.google.com with ESMTPS id 13sm1242684bwz.6.2010.01.22.16.19.40 (version=SSLv3 cipher=RC4-MD5); Fri, 22 Jan 2010 16:19:42 -0800 (PST) Subject: [PATCH 1/8] blktrans: nuke mtd_blkcore_priv and make both thread and disk queue be per device From: Maxim Levitsky To: Artem Bityutskiy In-Reply-To: <1264205925.31827.3.camel@maxim-laptop> References: <1264205925.31827.3.camel@maxim-laptop> Date: Sat, 23 Jan 2010 02:19:38 +0200 Message-ID: <1264205978.31827.4.camel@maxim-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 X-CRM114-Version: 20090807-BlameThorstenAndJenny ( TRE 0.7.6 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20100122_191943_641111_3DCC7F3E X-CRM114-Status: GOOD ( 24.36 ) X-Spam-Score: 0.0 (/) X-Spam-Report: SpamAssassin version 3.2.5 on bombadil.infradead.org summary: Content analysis details: (0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- _SUMMARY_ Cc: Alex Dubov , joern , linux-kernel , linux-mtd , Thomas Gleixner , David Woodhouse X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-mtd-bounces@lists.infradead.org Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org >From b18c2e01321b68dccbd2ea4ea321667687747173 Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Sat, 23 Jan 2010 02:00:37 +0200 Subject: [PATCH 1/8] blktrans: nuke mtd_blkcore_priv and make both thread and disk queue be per device This is the biggest change. To make hotplug possible, and this layer clearer, now mtd_blktrans_dev contains everything for a single mtd block translation device. Also removed some very old leftovers Signed-off-by: Maxim Levitsky --- drivers/mtd/mtd_blkdevs.c | 123 ++++++++++++++++++++---------------------- include/linux/mtd/blktrans.h | 10 ++-- 2 files changed, 64 insertions(+), 69 deletions(-) diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c index c82e09b..3d9802e 100644 --- a/drivers/mtd/mtd_blkdevs.c +++ b/drivers/mtd/mtd_blkdevs.c @@ -26,11 +26,6 @@ static LIST_HEAD(blktrans_majors); -struct mtd_blkcore_priv { - struct task_struct *thread; - struct request_queue *rq; - spinlock_t queue_lock; -}; static int do_blktrans_request(struct mtd_blktrans_ops *tr, struct mtd_blktrans_dev *dev, @@ -80,14 +75,13 @@ static int do_blktrans_request(struct mtd_blktrans_ops *tr, static int mtd_blktrans_thread(void *arg) { - struct mtd_blktrans_ops *tr = arg; - struct request_queue *rq = tr->blkcore_priv->rq; + struct mtd_blktrans_dev *dev = arg; + struct request_queue *rq = dev->rq; struct request *req = NULL; spin_lock_irq(rq->queue_lock); while (!kthread_should_stop()) { - struct mtd_blktrans_dev *dev; int res; if (!req && !(req = blk_fetch_request(rq))) { @@ -98,13 +92,10 @@ static int mtd_blktrans_thread(void *arg) continue; } - dev = req->rq_disk->private_data; - tr = dev->tr; - spin_unlock_irq(rq->queue_lock); mutex_lock(&dev->lock); - res = do_blktrans_request(tr, dev, req); + res = do_blktrans_request(dev->tr, dev, req); mutex_unlock(&dev->lock); spin_lock_irq(rq->queue_lock); @@ -123,8 +114,8 @@ static int mtd_blktrans_thread(void *arg) static void mtd_blktrans_request(struct request_queue *rq) { - struct mtd_blktrans_ops *tr = rq->queuedata; - wake_up_process(tr->blkcore_priv->thread); + struct mtd_blktrans_dev *dev = rq->queuedata; + wake_up_process(dev->thread); } @@ -214,6 +205,7 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new) struct mtd_blktrans_dev *d; int last_devnum = -1; struct gendisk *gd; + int ret; if (mutex_trylock(&mtd_table_mutex)) { mutex_unlock(&mtd_table_mutex); @@ -239,12 +231,13 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new) } last_devnum = d->devnum; } + + ret = -EBUSY; if (new->devnum == -1) new->devnum = last_devnum+1; - if ((new->devnum << tr->part_bits) > 256) { - return -EBUSY; - } + if ((new->devnum << tr->part_bits) > 256) + goto error1; list_add_tail(&new->list, &tr->devs); added: @@ -252,11 +245,16 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new) if (!tr->writesect) new->readonly = 1; + + /* Create gendisk */ + ret = -ENOMEM; gd = alloc_disk(1 << tr->part_bits); - if (!gd) { - list_del(&new->list); - return -ENOMEM; - } + + if (!gd) + goto error2; + + new->disk = gd; + gd->private_data = new; gd->major = tr->major; gd->first_minor = (new->devnum) << tr->part_bits; gd->fops = &mtd_blktrans_ops; @@ -274,13 +272,33 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new) snprintf(gd->disk_name, sizeof(gd->disk_name), "%s%d", tr->name, new->devnum); - /* 2.5 has capacity in units of 512 bytes while still - having BLOCK_SIZE_BITS set to 10. Just to keep us amused. */ set_capacity(gd, (new->size * tr->blksize) >> 9); - gd->private_data = new; - new->blkcore_priv = gd; - gd->queue = tr->blkcore_priv->rq; + + /* Create the request queue */ + spin_lock_init(&new->queue_lock); + new->rq = blk_init_queue(mtd_blktrans_request, &new->queue_lock); + + if (!new->rq) + goto error3; + + new->rq->queuedata = new; + blk_queue_logical_block_size(new->rq, tr->blksize); + + if (tr->discard) + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, + new->rq); + + gd->queue = new->rq; + + /* Create processing thread */ + /* TODO: workqueue ? */ + new->thread = kthread_run(mtd_blktrans_thread, new, + "%s%d", tr->name, new->mtd->index); + if (IS_ERR(new->thread)) { + ret = PTR_ERR(new->thread); + goto error4; + } gd->driverfs_dev = &new->mtd->dev; if (new->readonly) @@ -289,6 +307,15 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new) add_disk(gd); return 0; +error4: + blk_cleanup_queue(new->rq); +error3: + put_disk(new->disk); +error2: + list_del(&new->list); +error1: + kfree(new); + return ret; } int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old) @@ -300,9 +327,13 @@ int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old) list_del(&old->list); - del_gendisk(old->blkcore_priv); - put_disk(old->blkcore_priv); + /* stop new requests to arrive */ + del_gendisk(old->disk); + /* Stop the thread */ + kthread_stop(old->thread); + + blk_cleanup_queue(old->rq); return 0; } @@ -343,9 +374,6 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr) if (!blktrans_notifier.list.next) register_mtd_user(&blktrans_notifier); - tr->blkcore_priv = kzalloc(sizeof(*tr->blkcore_priv), GFP_KERNEL); - if (!tr->blkcore_priv) - return -ENOMEM; mutex_lock(&mtd_table_mutex); @@ -353,39 +381,12 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr) if (ret) { printk(KERN_WARNING "Unable to register %s block device on major %d: %d\n", tr->name, tr->major, ret); - kfree(tr->blkcore_priv); mutex_unlock(&mtd_table_mutex); return ret; } - spin_lock_init(&tr->blkcore_priv->queue_lock); - - tr->blkcore_priv->rq = blk_init_queue(mtd_blktrans_request, &tr->blkcore_priv->queue_lock); - if (!tr->blkcore_priv->rq) { - unregister_blkdev(tr->major, tr->name); - kfree(tr->blkcore_priv); - mutex_unlock(&mtd_table_mutex); - return -ENOMEM; - } - - tr->blkcore_priv->rq->queuedata = tr; - blk_queue_logical_block_size(tr->blkcore_priv->rq, tr->blksize); - if (tr->discard) - queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, - tr->blkcore_priv->rq); tr->blkshift = ffs(tr->blksize) - 1; - tr->blkcore_priv->thread = kthread_run(mtd_blktrans_thread, tr, - "%sd", tr->name); - if (IS_ERR(tr->blkcore_priv->thread)) { - ret = PTR_ERR(tr->blkcore_priv->thread); - blk_cleanup_queue(tr->blkcore_priv->rq); - unregister_blkdev(tr->major, tr->name); - kfree(tr->blkcore_priv); - mutex_unlock(&mtd_table_mutex); - return ret; - } - INIT_LIST_HEAD(&tr->devs); list_add(&tr->list, &blktrans_majors); @@ -405,8 +406,6 @@ int deregister_mtd_blktrans(struct mtd_blktrans_ops *tr) mutex_lock(&mtd_table_mutex); - /* Clean up the kernel thread */ - kthread_stop(tr->blkcore_priv->thread); /* Remove it from the list of active majors */ list_del(&tr->list); @@ -414,13 +413,9 @@ int deregister_mtd_blktrans(struct mtd_blktrans_ops *tr) list_for_each_entry_safe(dev, next, &tr->devs, list) tr->remove_dev(dev); - blk_cleanup_queue(tr->blkcore_priv->rq); unregister_blkdev(tr->major, tr->name); - mutex_unlock(&mtd_table_mutex); - kfree(tr->blkcore_priv); - BUG_ON(!list_empty(&tr->devs)); return 0; } diff --git a/include/linux/mtd/blktrans.h b/include/linux/mtd/blktrans.h index 8b4aa05..a4b3928 100644 --- a/include/linux/mtd/blktrans.h +++ b/include/linux/mtd/blktrans.h @@ -24,11 +24,13 @@ struct mtd_blktrans_dev { int devnum; unsigned long size; int readonly; - void *blkcore_priv; /* gendisk in 2.5, devfs_handle in 2.4 */ + struct gendisk *disk; + struct task_struct *thread; + struct request_queue *rq; + spinlock_t queue_lock; + void *priv; }; -struct blkcore_priv; /* Differs for 2.4 and 2.5 kernels; private */ - struct mtd_blktrans_ops { char *name; int major; @@ -60,8 +62,6 @@ struct mtd_blktrans_ops { struct list_head devs; struct list_head list; struct module *owner; - - struct mtd_blkcore_priv *blkcore_priv; }; extern int register_mtd_blktrans(struct mtd_blktrans_ops *tr);