BLKDEV_GET_BY_DEV(9) The Linux VFS BLKDEV_GET_BY_DEV(9)NAME
blkdev_get_by_dev - open a block device by device number
struct block_device * blkdev_get_by_dev(dev_t dev, fmode_t mode, void * holder);
device number of block device to open
exclusive holder identifier
Open the blockdevice described by device number dev. mode and holder are identical to blkdev_get.
Use it ONLY if you really do not have anything better - i.e. when you are behind a truly sucky interface and all you are given is a device
number. _Never_ to be used for internal purposes. If you ever need it - reconsider your API.
On success, the returned block_device has reference count of one.
Pointer to block_device on success, ERR_PTR(-errno) on failure.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 BLKDEV_GET_BY_DEV(9)
Check Out this Related Man Page
DEVICE_CREATE_VARGS(9) Device drivers infrastructure DEVICE_CREATE_VARGS(9)NAME
device_create_vargs - creates a device and registers it with sysfs
struct device * device_create_vargs(struct class * class, struct device * parent, dev_t devt, void * drvdata, const char * fmt,
pointer to the struct class that this device should be registered to
pointer to the parent struct device of this new device, if any
the dev_t for the char device to be added
the data to be added to the device for callbacks
string for the device's name
va_list for the device's name
This function can be used by char device classes. A struct device will be created in sysfs, registered to the specified class.
A "dev" file will be created, showing the dev_t for the device, if the dev_t is not 0,0. If a pointer to a parent struct device is passed
in, the newly created struct device will be a child of that device in sysfs. The pointer to the struct device will be returned from the
call. Any further sysfs files that might be required can be created using this pointer.
Returns struct device pointer on success, or ERR_PTR on error.
the struct class passed to this function must have previously been created with a call to class_create.
COPYRIGHT Kernel Hackers Manual 2.6. July 2010 DEVICE_CREATE_VARGS(9)
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