• Sebastian Ott's avatar
    [S390] cio: introduce cio_commit_config · 13952ec1
    Sebastian Ott authored
    To change the configuration of a subchannel we alter the modifiable
    bits of the subchannel's schib field and issue a modify subchannel.
    There can be the case that not all changes were applied -or worse-
    quietly overwritten by the hardware. With the next store subchannel
    we obtain the current state of the hardware but lose our target
    configuration.
    
    With this patch we introduce a subchannel_config structure which
    contains the target subchannel configuration. Additionally the msch
    wrapper cio_modify is replaced with cio_commit_config which
    copies the desired changes to a temporary schib. msch is then
    called with the temporary schib. This schib is only written back
    to the subchannel if all changes were applied.
    Signed-off-by: default avatarSebastian Ott <sebott@linux.vnet.ibm.com>
    Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
    13952ec1
css.c 21.4 KB