dasd_is_ro() uses the O_RDWR flag when opening the file descriptor.
However, an attempt to open the file descriptor of a device that is in
read-only state will fail and the BLKROGET ioctl that is used to
actually determine the read-only state can't be issued.
Change the flag to O_RDONLY to fix this.
Fixes: a5c1923d32 ("libdasd: Add common DASD ioctl's to the lib")
Reviewed-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
The BIODASDRAS (Release Allocated Space) ioctl allows to release
track-wise or full space of an Extent Space Efficient DASD volume.
Provide a library function to utilise this functionality.
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Enable zdsfs to access datasets that were created after zdsfs was
mounted without the need to remount zdsfs.
This is done by re-reading the VTOC with every readdir system call.
To ensure a consistent VTOC state the DASD device is reserved for
every VTOC read and released afterwards.
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
