Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765085AbXLTWSG (ORCPT ); Thu, 20 Dec 2007 17:18:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764823AbXLTWQO (ORCPT ); Thu, 20 Dec 2007 17:16:14 -0500 Received: from baron.coile-labs.com ([65.14.39.133]:28908 "EHLO coraid.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1762248AbXLTWQM (ORCPT ); Thu, 20 Dec 2007 17:16:12 -0500 From: "Ed L. Cashin" To: linux-kernel@vger.kernel.org Cc: "Ed L. Cashin" , Andrew Morton Subject: [PATCH 06/13] user can ask driver to forget previously detected devices Date: Thu, 20 Dec 2007 17:15:54 -0500 Message-Id: <1198188961-25147-6-git-send-email-ecashin@coraid.com> X-Mailer: git-send-email 1.5.3.4 In-Reply-To: <1198188961-25147-1-git-send-email-ecashin@coraid.com> References: <1198188961-25147-1-git-send-email-ecashin@coraid.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5691 Lines: 206 When an AoE device is detected, the kernel is informed, and a new block device is created. If the device is unused, the block device corresponding to remote device that is no longer available may be removed from the system by telling the aoe driver to "flush" its list of devices. Without this patch, software like GPFS and LVM may attempt to read from AoE devices that were discovered earlier but are no longer present, blocking until the I/O attempt times out. Signed-off-by: Ed L. Cashin --- Documentation/aoe/mkdevs.sh | 2 + Documentation/aoe/udev.txt | 1 + drivers/block/aoe/aoe.h | 1 + drivers/block/aoe/aoechr.c | 5 ++ drivers/block/aoe/aoedev.c | 87 +++++++++++++++++++++++++++++++++--------- 5 files changed, 77 insertions(+), 19 deletions(-) diff --git a/Documentation/aoe/mkdevs.sh b/Documentation/aoe/mkdevs.sh index 97374aa..44c0ab7 100644 --- a/Documentation/aoe/mkdevs.sh +++ b/Documentation/aoe/mkdevs.sh @@ -29,6 +29,8 @@ rm -f $dir/interfaces mknod -m 0200 $dir/interfaces c $MAJOR 4 rm -f $dir/revalidate mknod -m 0200 $dir/revalidate c $MAJOR 5 +rm -f $dir/flush +mknod -m 0200 $dir/flush c $MAJOR 6 export n_partitions mkshelf=`echo $0 | sed 's!mkdevs!mkshelf!'` diff --git a/Documentation/aoe/udev.txt b/Documentation/aoe/udev.txt index 17e76c4..8686e78 100644 --- a/Documentation/aoe/udev.txt +++ b/Documentation/aoe/udev.txt @@ -20,6 +20,7 @@ SUBSYSTEM=="aoe", KERNEL=="discover", NAME="etherd/%k", GROUP="disk", MODE="0220 SUBSYSTEM=="aoe", KERNEL=="err", NAME="etherd/%k", GROUP="disk", MODE="0440" SUBSYSTEM=="aoe", KERNEL=="interfaces", NAME="etherd/%k", GROUP="disk", MODE="0220" SUBSYSTEM=="aoe", KERNEL=="revalidate", NAME="etherd/%k", GROUP="disk", MODE="0220" +SUBSYSTEM=="aoe", KERNEL=="flush", NAME="etherd/%k", GROUP="disk", MODE="0220" # aoe block devices KERNEL=="etherd*", NAME="%k", GROUP="disk" diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h index aecaac3..2248ab2 100644 --- a/drivers/block/aoe/aoe.h +++ b/drivers/block/aoe/aoe.h @@ -191,6 +191,7 @@ struct aoedev *aoedev_by_aoeaddr(int maj, int min); struct aoedev *aoedev_by_sysminor_m(ulong sysminor); void aoedev_downdev(struct aoedev *d); int aoedev_isbusy(struct aoedev *d); +int aoedev_flush(const char __user *str, size_t size); int aoenet_init(void); void aoenet_exit(void); diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c index f112466..1bc85aa 100644 --- a/drivers/block/aoe/aoechr.c +++ b/drivers/block/aoe/aoechr.c @@ -15,6 +15,7 @@ enum { MINOR_DISCOVER, MINOR_INTERFACES, MINOR_REVALIDATE, + MINOR_FLUSH, MSGSZ = 2048, NMSG = 100, /* message backlog to retain */ }; @@ -43,6 +44,7 @@ static struct aoe_chardev chardevs[] = { { MINOR_DISCOVER, "discover" }, { MINOR_INTERFACES, "interfaces" }, { MINOR_REVALIDATE, "revalidate" }, + { MINOR_FLUSH, "flush" }, }; static int @@ -158,6 +160,9 @@ aoechr_write(struct file *filp, const char __user *buf, size_t cnt, loff_t *offp break; case MINOR_REVALIDATE: ret = revalidate(buf, cnt); + break; + case MINOR_FLUSH: + ret = aoedev_flush(buf, cnt); } if (ret == 0) ret = cnt; diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c index a4d625a..e26f6f4 100644 --- a/drivers/block/aoe/aoedev.c +++ b/drivers/block/aoe/aoedev.c @@ -9,6 +9,10 @@ #include #include "aoe.h" +static void dummy_timer(ulong); +static void aoedev_freedev(struct aoedev *); +static void freetgt(struct aoetgt *t); + static struct aoedev *devlist; static spinlock_t devlist_lock; @@ -108,6 +112,70 @@ aoedev_downdev(struct aoedev *d) d->flags &= ~DEVFL_UP; } +static void +aoedev_freedev(struct aoedev *d) +{ + struct aoetgt **t, **e; + + if (d->gd) { + aoedisk_rm_sysfs(d); + del_gendisk(d->gd); + put_disk(d->gd); + } + t = d->targets; + e = t + NTARGETS; + for (; t < e && *t; t++) + freetgt(*t); + if (d->bufpool) + mempool_destroy(d->bufpool); + kfree(d); +} + +int +aoedev_flush(const char __user *str, size_t cnt) +{ + ulong flags; + struct aoedev *d, **dd; + struct aoedev *rmd = NULL; + char buf[16]; + int all = 0; + + if (cnt >= 3) { + if (cnt > sizeof buf) + cnt = sizeof buf; + if (copy_from_user(buf, str, cnt)) + return -EFAULT; + all = !strncmp(buf, "all", 3); + } + + flush_scheduled_work(); + spin_lock_irqsave(&devlist_lock, flags); + dd = &devlist; + while ((d = *dd)) { + spin_lock(&d->lock); + if ((!all && (d->flags & DEVFL_UP)) + || (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE)) + || d->nopen) { + spin_unlock(&d->lock); + dd = &d->next; + continue; + } + *dd = d->next; + aoedev_downdev(d); + d->flags |= DEVFL_TKILL; + spin_unlock(&d->lock); + d->next = rmd; + rmd = d; + } + spin_unlock_irqrestore(&devlist_lock, flags); + while ((d = rmd)) { + rmd = d->next; + del_timer_sync(&d->timer); + aoedev_freedev(d); /* must be able to sleep */ + } + return 0; +} + /* find it or malloc it */ struct aoedev * aoedev_by_sysminor_m(ulong sysminor) @@ -161,25 +229,6 @@ freetgt(struct aoetgt *t) kfree(t); } -static void -aoedev_freedev(struct aoedev *d) -{ - struct aoetgt **t, **e; - - if (d->gd) { - aoedisk_rm_sysfs(d); - del_gendisk(d->gd); - put_disk(d->gd); - } - t = d->targets; - e = t + NTARGETS; - for (; t < e && *t; t++) - freetgt(*t); - if (d->bufpool) - mempool_destroy(d->bufpool); - kfree(d); -} - void aoedev_exit(void) { -- 1.5.3.4 -- 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/