• Harald Freudenberger's avatar
    s390/zcrypt: hex string mask improvements for apmask and aqmask. · 3d8f60d3
    Harald Freudenberger authored
    The sysfs attributes /sys/bus/ap/apmask and /sys/bus/ap/aqmask
    and the kernel command line arguments ap.apm and ap.aqm get
    an improvement of the value parsing with this patch:
    
    The mask values are bitmaps in big endian order starting with bit 0.
    So adapter number 0 is the leftmost bit, mask is 0x8000... The sysfs
    attributes and the kernel command line accept 2 different formats:
     - Absolute hex string starting with 0x like "0x12345678" does set
       the mask starting from left to right. If the given string is shorter
       than the mask it is padded with 0s on the right. If the string is
       longer than the mask an error comes back (EINVAL).
     - Relative format - a concatenation (done with ',') of the terms
       +<bitnr>[-<bitnr>] or -<bitnr>[-<bitnr>]. <bitnr> may be any
       valid number (hex, decimal or octal) in the range 0...255.
       Here are some examples:
         "+0-15,+32,-128,-0xFF"
         "-0-255,+1-16,+0x128"
    Signed-off-by: default avatarHarald Freudenberger <freude@linux.ibm.com>
    Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
    3d8f60d3
ap_bus.c 40 KB