mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
s390/mm: allow to check if a gmap shadow is valid
It will be very helpful to have a mechanism to check without any locks if a given gmap shadow is still valid and matches the given properties. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
parent
4a49443924
commit
5b6c963bce
2 changed files with 21 additions and 0 deletions
|
@ -109,6 +109,7 @@ int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val);
|
|||
|
||||
struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce,
|
||||
int edat_level);
|
||||
int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level);
|
||||
int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t,
|
||||
int fake);
|
||||
int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t,
|
||||
|
|
|
@ -1407,6 +1407,26 @@ static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce,
|
|||
return NULL;
|
||||
}
|
||||
|
||||
/**
|
||||
* gmap_shadow_valid - check if a shadow guest address space matches the
|
||||
* given properties and is still valid
|
||||
* @sg: pointer to the shadow guest address space structure
|
||||
* @asce: ASCE for which the shadow table is requested
|
||||
* @edat_level: edat level to be used for the shadow translation
|
||||
*
|
||||
* Returns 1 if the gmap shadow is still valid and matches the given
|
||||
* properties, the caller can continue using it. Returns 0 otherwise, the
|
||||
* caller has to request a new shadow gmap in this case.
|
||||
*
|
||||
*/
|
||||
int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level)
|
||||
{
|
||||
if (sg->removed)
|
||||
return 0;
|
||||
return sg->orig_asce == asce && sg->edat_level == edat_level;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(gmap_shadow_valid);
|
||||
|
||||
/**
|
||||
* gmap_shadow - create/find a shadow guest address space
|
||||
* @parent: pointer to the parent gmap
|
||||
|
|
Loading…
Reference in a new issue