From: Jarod Wilson <jarod@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: Jarod Wilson <jarod@redhat.com>,
Christoph Hellwig <hch@infradead.org>,
Jens Axboe <axboe@kernel.dk>, Tejun Heo <tj@kernel.org>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Markus Pargmann <mpa@pengutronix.de>,
Stefan Weinhuber <wein@de.ibm.com>,
Stefan Haberland <stefan.haberland@de.ibm.com>,
Sebastian Ott <sebott@linux.vnet.ibm.com>,
Fabian Frederick <fabf@skynet.be>,
Ming Lei <ming.lei@canonical.com>,
David Herrmann <dh.herrmann@gmail.com>,
Mike Galbraith <bitbucket@online.de>,
Andrew Morton <akpm@linux-foundation.org>,
Peter Zijlstra <peterz@infradead.org>,
nbd-general@lists.sourceforge.net, linux-s390@vger.kernel.org
Subject: [PATCH 1/7] block: export blkdev_reread_part() and __blkdev_reread_part()
Date: Wed, 8 Apr 2015 02:23:40 -0400 [thread overview]
Message-ID: <1428474226-27386-2-git-send-email-jarod@redhat.com> (raw)
In-Reply-To: <1428474226-27386-1-git-send-email-jarod@redhat.com>
This patch exports blkdev_reread_part() for block drivers, also
introduce __blkdev_reread_part(), a lockless version.
For some drivers, such as loop, a reread of partitions can be run
from the release path, and bd_mutex may already be held prior to
calling ioctl_by_bdev(bdev, BLKRRPART, 0), so introduce a lockless
path for use in such cases.
CC: Christoph Hellwig <hch@infradead.org>
CC: Jens Axboe <axboe@kernel.dk>
CC: Tejun Heo <tj@kernel.org>
CC: Alexander Viro <viro@zeniv.linux.org.uk>
CC: Markus Pargmann <mpa@pengutronix.de>
CC: Stefan Weinhuber <wein@de.ibm.com>
CC: Stefan Haberland <stefan.haberland@de.ibm.com>
CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
CC: Fabian Frederick <fabf@skynet.be>
CC: Ming Lei <ming.lei@canonical.com>
CC: David Herrmann <dh.herrmann@gmail.com>
CC: Mike Galbraith <bitbucket@online.de>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Peter Zijlstra <peterz@infradead.org>
CC: nbd-general@lists.sourceforge.net
CC: linux-s390@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
---
block/ioctl.c | 26 +++++++++++++++++++++++---
include/linux/fs.h | 3 +++
2 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/block/ioctl.c b/block/ioctl.c
index 7d8befd..64a4fcb 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -150,21 +150,41 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user
}
}
-static int blkdev_reread_part(struct block_device *bdev)
+/*
+ * This is an exported API for the block driver, and will not
+ * acquire bd_mutex, leaving it up to the caller to handle
+ * any necessary locking.
+ */
+int __blkdev_reread_part(struct block_device *bdev)
{
struct gendisk *disk = bdev->bd_disk;
- int res;
if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains)
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
+
+ return rescan_partitions(disk, bdev);
+}
+EXPORT_SYMBOL(__blkdev_reread_part);
+
+/*
+ * This is an exported API for the block driver, and will
+ * acquire bd_mutex. Make sure you aren't calling it with
+ * bd_mutex already held, or we'll return -EBUSY.
+ */
+int blkdev_reread_part(struct block_device *bdev)
+{
+ int res;
+
if (!mutex_trylock(&bdev->bd_mutex))
return -EBUSY;
- res = rescan_partitions(disk, bdev);
+ res = __blkdev_reread_part(bdev);
mutex_unlock(&bdev->bd_mutex);
+
return res;
}
+EXPORT_SYMBOL(blkdev_reread_part);
static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
uint64_t len, int secure)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f4131e8..11398e3 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2245,6 +2245,9 @@ extern struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
extern struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode,
void *holder);
extern void blkdev_put(struct block_device *bdev, fmode_t mode);
+extern int __blkdev_reread_part(struct block_device *bdev);
+extern int blkdev_reread_part(struct block_device *bdev);
+
#ifdef CONFIG_SYSFS
extern int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk);
extern void bd_unlink_disk_holder(struct block_device *bdev,
--
1.8.3.1
next prev parent reply other threads:[~2015-04-08 6:24 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-05 7:24 [PATCH 0/6] block: reread partitions changes and fix for loop Ming Lei
2015-04-05 7:24 ` [PATCH 1/6] block: export blkdev_reread_part() Ming Lei
2015-04-05 16:12 ` Christoph Hellwig
2015-04-05 16:40 ` Ming Lei
2015-04-06 13:42 ` Jarod Wilson
2015-04-06 13:48 ` Jarod Wilson
2015-04-07 2:43 ` Ming Lei
2015-04-06 14:50 ` Christoph Hellwig
2015-04-07 2:11 ` Ming Lei
2015-04-05 7:24 ` [PATCH 2/6] block: loop: don't hold lo_ctl_mutex in lo_open Ming Lei
2015-04-05 16:28 ` Ming Lei
2015-04-06 14:49 ` Christoph Hellwig
2015-04-05 7:24 ` [PATCH 3/6] block: loop: fix another reread part failure Ming Lei
2015-04-05 7:24 ` [PATCH 4/6] block: nbd: convert to blkdev_reread_part() Ming Lei
2015-04-05 7:24 ` [PATCH 5/6] block: dasd_genhd: convert to blkdev_reread_part Ming Lei
2015-04-06 13:46 ` Jarod Wilson
2015-04-06 13:51 ` Jarod Wilson
2015-04-07 1:59 ` Ming Lei
2015-04-07 0:47 ` Ming Lei
2015-04-05 7:24 ` [RFC PATCH 6/6] block: replace trylock with mutex_lock in __blkdev_reread_part() Ming Lei
2015-04-08 6:23 ` [PATCH 0/7] block: reread partitions improvements Jarod Wilson
2015-04-08 6:23 ` Jarod Wilson [this message]
2015-04-08 14:50 ` [PATCH 1/7] block: export blkdev_reread_part() and __blkdev_reread_part() Ming Lei
2015-04-08 15:03 ` Peter Zijlstra
2015-04-08 15:27 ` Jarod Wilson
2015-04-08 15:28 ` Ming Lei
2015-04-08 6:23 ` [PATCH 2/7] block: loop: don't hold lo_ctl_mutex in lo_open Jarod Wilson
2015-04-08 6:50 ` Ming Lei
2015-04-08 13:40 ` Jarod Wilson
2015-04-08 14:00 ` Jarod Wilson
2015-04-08 14:20 ` Ming Lei
2015-04-08 15:28 ` Jarod Wilson
2015-04-08 6:23 ` [PATCH 3/7] block: loop: fix another reread part failure Jarod Wilson
2015-04-08 6:23 ` [PATCH 4/7] block: nbd: convert to blkdev_reread_part() Jarod Wilson
2015-04-08 6:23 ` [PATCH 5/7] block: dasd_genhd: convert to blkdev_reread_part Jarod Wilson
2015-04-08 6:23 ` [PATCH 6/7] block: replace trylock with mutex_lock in blkdev_reread_part() Jarod Wilson
2015-04-08 6:23 ` [PATCH 7/7] s390/block/dasd: remove obsolete while -EBUSY loop Jarod Wilson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1428474226-27386-2-git-send-email-jarod@redhat.com \
--to=jarod@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=axboe@kernel.dk \
--cc=bitbucket@online.de \
--cc=dh.herrmann@gmail.com \
--cc=fabf@skynet.be \
--cc=hch@infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=ming.lei@canonical.com \
--cc=mpa@pengutronix.de \
--cc=nbd-general@lists.sourceforge.net \
--cc=peterz@infradead.org \
--cc=sebott@linux.vnet.ibm.com \
--cc=stefan.haberland@de.ibm.com \
--cc=tj@kernel.org \
--cc=viro@zeniv.linux.org.uk \
--cc=wein@de.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).