linux/arch/s390/mm
Carsten Otte 402b08622d s390: KVM preparation: provide hook to enable pgstes in user pagetable
The SIE instruction on s390 uses the 2nd half of the page table page to
virtualize the storage keys of a guest. This patch offers the s390_enable_sie
function, which reorganizes the page tables of a single-threaded process to
reserve space in the page table:
s390_enable_sie makes sure that the process is single threaded and then uses
dup_mm to create a new mm with reorganized page tables. The old mm is freed
and the process has now a page status extended field after every page table.

Code that wants to exploit pgstes should SELECT CONFIG_PGSTE.

This patch has a small common code hit, namely making dup_mm non-static.

Edit (Carsten): I've modified Martin's patch, following Jeremy Fitzhardinge's
review feedback. Now we do have the prototype for dup_mm in
include/linux/sched.h. Following Martin's suggestion, s390_enable_sie() does now
call task_lock() to prevent race against ptrace modification of mm_users.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-04-27 12:00:40 +03:00
..
cmm.c [S390] cmm: remove unused binary sysctls. 2007-11-20 11:13:45 +01:00
extmem.c [S390] Remove code duplication from monreader / dcssblk. 2008-04-17 07:47:07 +02:00
fault.c [S390] Fix a lot of sparse warnings. 2008-04-17 07:47:06 +02:00
init.c [S390] remove redundant display of free swap space in show_mem() 2008-04-17 07:47:04 +02:00
Makefile [S390] Cleanup page table definitions. 2007-10-22 12:52:49 +02:00
mmap.c [S390] dynamic page tables. 2008-02-09 18:24:41 +01:00
pgtable.c s390: KVM preparation: provide hook to enable pgstes in user pagetable 2008-04-27 12:00:40 +03:00
vmem.c [S390] Add four level page tables for CONFIG_64BIT=y. 2008-02-09 18:24:40 +01:00