From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Thu, 17 Sep 2020 18:57:13 +0200 Subject: [Ocfs2-devel] [PATCH 07/14] raw: don't keep unopened block device around In-Reply-To: <20200917165720.3285256-1-hch@lst.de> References: <20200917165720.3285256-1-hch@lst.de> Message-ID: <20200917165720.3285256-8-hch@lst.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Jens Axboe Cc: Josef Bacik , Minchan Kim , Stefan Haberland , Jan Hoeppner , Joseph Qi , "Rafael J. Wysocki" , Pavel Machek , Len Brown , Andrew Morton , linux-kernel@vger.kernel.org, nbd@other.debian.org, linux-ide@vger.kernel.org, linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org, ocfs2-devel@oss.oracle.com, linux-pm@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org Turn binding into a normal dev_t as the struct block device doesn't buy us anything and use blkdev_open_by_dev to actually open it. Signed-off-by: Christoph Hellwig --- drivers/char/raw.c | 51 +++++++++++++++++----------------------------- 1 file changed, 19 insertions(+), 32 deletions(-) diff --git a/drivers/char/raw.c b/drivers/char/raw.c index ccf5bd528642da..5d52a1f4738c76 100644 --- a/drivers/char/raw.c +++ b/drivers/char/raw.c @@ -28,7 +28,8 @@ #include struct raw_device_data { - struct block_device *binding; + dev_t binding; + struct block_device *bdev; int inuse; }; @@ -73,14 +74,15 @@ static int raw_open(struct inode *inode, struct file *filp) /* * All we need to do on open is check that the device is bound. */ - bdev = raw_devices[minor].binding; err = -ENODEV; - if (!bdev) + if (!raw_devices[minor].binding) goto out; - bdgrab(bdev); - err = blkdev_get(bdev, filp->f_mode | FMODE_EXCL, raw_open); - if (err) + bdev = blkdev_get_by_dev(raw_devices[minor].binding, + filp->f_mode | FMODE_EXCL, raw_open); + if (IS_ERR(bdev)) { + err = PTR_ERR(bdev); goto out; + } err = set_blocksize(bdev, bdev_logical_block_size(bdev)); if (err) goto out1; @@ -90,6 +92,7 @@ static int raw_open(struct inode *inode, struct file *filp) file_inode(filp)->i_mapping = bdev->bd_inode->i_mapping; filp->private_data = bdev; + raw_devices[minor].bdev = bdev; mutex_unlock(&raw_mutex); return 0; @@ -110,7 +113,7 @@ static int raw_release(struct inode *inode, struct file *filp) struct block_device *bdev; mutex_lock(&raw_mutex); - bdev = raw_devices[minor].binding; + bdev = raw_devices[minor].bdev; if (--raw_devices[minor].inuse == 0) /* Here inode->i_mapping == bdev->bd_inode->i_mapping */ inode->i_mapping = &inode->i_data; @@ -133,6 +136,7 @@ raw_ioctl(struct file *filp, unsigned int command, unsigned long arg) static int bind_set(int number, u64 major, u64 minor) { dev_t dev = MKDEV(major, minor); + dev_t raw = MKDEV(RAW_MAJOR, number); struct raw_device_data *rawdev; int err = 0; @@ -166,25 +170,17 @@ static int bind_set(int number, u64 major, u64 minor) mutex_unlock(&raw_mutex); return -EBUSY; } - if (rawdev->binding) { - bdput(rawdev->binding); + if (rawdev->binding) module_put(THIS_MODULE); - } + + rawdev->binding = dev; if (!dev) { /* unbind */ - rawdev->binding = NULL; - device_destroy(raw_class, MKDEV(RAW_MAJOR, number)); + device_destroy(raw_class, raw); } else { - rawdev->binding = bdget(dev); - if (rawdev->binding == NULL) { - err = -ENOMEM; - } else { - dev_t raw = MKDEV(RAW_MAJOR, number); - __module_get(THIS_MODULE); - device_destroy(raw_class, raw); - device_create(raw_class, NULL, raw, NULL, - "raw%d", number); - } + __module_get(THIS_MODULE); + device_destroy(raw_class, raw); + device_create(raw_class, NULL, raw, NULL, "raw%d", number); } mutex_unlock(&raw_mutex); return err; @@ -192,18 +188,9 @@ static int bind_set(int number, u64 major, u64 minor) static int bind_get(int number, dev_t *dev) { - struct raw_device_data *rawdev; - struct block_device *bdev; - if (number <= 0 || number >= max_raw_minors) return -EINVAL; - - rawdev = &raw_devices[number]; - - mutex_lock(&raw_mutex); - bdev = rawdev->binding; - *dev = bdev ? bdev->bd_dev : 0; - mutex_unlock(&raw_mutex); + *dev = raw_devices[number].binding; return 0; } -- 2.28.0