The storage key for the 2K-byte block
that is addressed by the contents of
general register R2 is inserted in
general register R t • Bits 8-20 of general register R2 desig­
nate a 2K-byte block in real storage.
Bits 0-7 and 21-27 of the register are
ignored. Bits 28-31 of the register
must be zeros; otherwise, a specifica­
tion exception is recognized.
When the storage-key 4K-byte-block
facility is not installed, all blocks
are double-key 4K-byte blocks, and the
operation proceeds normally.
When the storage-key 4K-byte-block
facility is installed, all blocks are
single-key 4K-byte blocks, and the
action taken depends on the setting of
the storage-key-exception-control bit,
bit 7 of control register o. If the bit
is zero, a special-operation exception
is recognized. If the bit is one, the
operation is performed on the single key
for the 4K-byte block.
The address designating the storage
block, being a real address, 1S not
subject to dynamic address translation.
The reference to the storage key is not
subject to a protection exception.
The execution of the instruction depends
on whether the PSW specifies the EC or BC mode. In the EC mode, the seven-bit
storage key is inserted in bit positions 24-30 of general register Rt, and bit 31
is set to zero. In the BC mode, bits 0-4 of the storage key are placed in bit
positions 24-28 of that register, and
bits 29-31 of the register are set to
zeros. In both modes, the contents of
bit positions 0-23 of the register
remain unchanged.
Special Conditions
Bits 28-31 of general register R2 must
be zeros; otherwise, a specification
exception is recognized.
When the storage-key 4K-byte-block
facility is installed and the storage­
key-exception-control bit (bit 7 of
control register 0) is zero, a special­
operation exception is recognized. Condition Code: unchanged.
Program Exceptions:
The
Addressing (address
general register
Privileged operation
Special operation
Specification
code remains
by
INSERT STORAGE KEY EXTENDED
ISKE [RREl
'B229'
o 16 24
The storage key for the block
addressed by the contents of
register R2 is inserted in
register R t • 28 31
that is
general
general
Bits 16-23
ignored.
of the instruction are
The contents of general register R2 are
treated as a 31-bit real address of a
4K-byte block in storage. Bits 1-19 of
the register designate the 4K-byte
block, and bits 0 and 20-31 of the
register are ignored.
The address designating the storage
block, being a real address, is not
subject to dynamic address translation.
The reference to the storage key is not
subject to a protection exception.
When the storage-key 4K-byte-block
facility is not installed, all blocks
are double-key 4K-byte blocks. The key
for the first 2K-byte block within the
4K-byte block designated by the instruc­
tion is called the low-order key. The
key for the second 2K-byte block is
called the high-order key. The contents
of the low-order key are inserted, but
with the resultant change bit being the OR of the change bits from the low-order
and high-order keys. Similarly, the
resultant reference bit is the OR of the
reference bits from the low-order and high-order keys. The contents of the
storage keys are not changed.
When the storage-key 4K-byte-block
facility is installed, all blocks are
single-key 4K-byte blocks, and the
single key is inserted in the register.
The seven-bit storage key is inserted in
bit positions 24-30 of general register
R., and bit 31 is set to zero. The
contents of bit positions 0-23 of the
register remain unchanged. The opera­
tion is not dependent on whether the PSW
specifies the EC or BC mode. Condition Code: unchanged.
Program Exceptions:
The code remains
Addressing (address specified by
general register R2) Operation (if the storage-key­
instruction-extension facility
is not installed)
Privileged operation Chapter 10. Control Instructions 10-9

Programming Note
The results of the execution of INSERT STORAGE KEY EXTENDED for a double-key
4K-byte block may have intermediate
values for the reference and change bits
if there is a concurrent storage-key
operation being executed on either key
for the same double-key block by another CPU in the configuration.
INSERT VIRTUAL STORAGE KEY IVSK R I' R2 [RREl
'B223' 1////////1 R t R2 0 16 24 28 31
The storage key for the location desig­
nated by the virtual address in general
register R2 is inserted in general
register R, . Bits 16-23
ignored.
of the instruction are Bits 8-31 of general register R2 are
used as a virtual address. Bits 0-7 of
the register are ignored.
The address is a virtual address and is
subject to the address-space-control
bit, bit 16 of the current PSW. In the
primary-space mode, the address is
treated as a primary virtual address; in
the secondary-space mode, the address is
treated as a secondary virtual address.
The reference to the storage key is not
subject to a protection exception.
Bits 0-4 of the storage key, which are
the access-control bits and the fetch­
protection bit, are placed in bit posi­
tions 24-28 of general register Rt, with
bits 29-31 set to zeros. The contents
of bit positions 0-23 of the register
remain unchanged. The change and refer­ ence bits in the storage key are not
inspected. The change bit is not
affected by the operation. The refer­ ence bit, depending on the model, mayor
may not be set to one as a result of the operation. 10-10 System/370 Principles of Operation The following diagram shows the storage
key and the register positions just
described.
R t 0 Storage Key
for the
Location lAce \F\R\C\ J,eros '" I '" 24 28 31
Special Conditions The instruction must be executed with OAT on; otherwise, a special-operation
exception is recognized. The special­
operation exception is recognized in
both the problem and supervisor states.
In the problem state, the extraction­
authority control, bit 4 of control
register 0, must be one; otherwise, a
privileged-operation exception is recog­
nized. In the supervisor state, the
extraction-authority-control bit is not
examined.
The priority of recognition of program
exceptions for the instruction is shown
in the figure "Priority of Execution:
INSERT VIRTUAL STORAGE KEY." Condition Code: unchanged.
The code remains
Program Exceptions:
Access (except for
address specified
register R
2
) Operation (if the
space facility
installed)
protection,
by general
dual-address-
is not
Privileged operation (extraction­
authority control is the problem state)
Special operation
zero in