The powerpc kernel maintains information about logical memory blocks
in the lmb.memory structure, which is initialized and updated at boot
time, but not when memory is added or removed while the kernel is
running.
This adds a hotplug memory notifier which updates lmb.memory when
memory is added or removed. This information is useful for eHEA
driver to find out the memory layout and holes.
NOTE: No special locking is needed for lmb_add() and lmb_remove().
Calls to these are serialized by caller. (pSeries_reconfig_chain).
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Hotplug memory remove notifier for 64-bit powerpc. This gets invoked
by writing to /proc/ppc64/ofdt the string "remove_node " followed by
the firmware device tree pathname of the node that needs to be removed.
In response, this adjusts the sections and removes sysfs entries by
calling __remove_pages(). Then it calls arch-specific code to get rid
of the hardware MMU mappings for the section of memory.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Reviewed-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
