[PATCH 07/14] raw: don't keep unopened block device around
From: Christoph Hellwig <hch@lst.de>
Date: 2020-09-17 17:15:29
Also in:
linux-fsdevel, linux-ide, linux-mm, linux-pm, linux-s390, lkml, ocfs2-devel
Subsystem:
char and misc drivers, the rest · Maintainers:
Arnd Bergmann, Greg Kroah-Hartman, Linus Torvalds
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 <hch@lst.de> --- 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 <linux/uaccess.h> 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