On 1/16/25 12:33 PM, Claudio Imbrenda wrote:
Move gmap_shadow_pgt_lookup() from mm/gmap.c into kvm/gaccess.c .
Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
---
arch/s390/include/asm/gmap.h | 3 +--
arch/s390/kvm/gaccess.c | 40 +++++++++++++++++++++++++++++++
arch/s390/kvm/gmap.h | 2 ++
arch/s390/mm/gmap.c | 46 ++----------------------------------
4 files changed, 45 insertions(+), 46 deletions(-)
[...]
+/**
+ * gmap_shadow_pgt_lookup - find a shadow page table
The other two VSIE functions in gaccess.c have the kvm_s390_shadow
prefix but this one is only static anyway and hence we could just drop
the gmap_ from the name.
+ * @sg: pointer to the shadow guest address space structure
+ * @saddr: the address in the shadow aguest address space
+ * @pgt: parent gmap address of the page table to get shadowed
+ * @dat_protection: if the pgtable is marked as protected by dat
+ * @fake: pgt references contiguous guest memory block, not a pgtable
+ *
+ * Returns 0 if the shadow page table was found and -EAGAIN if the page
+ * table was not found.
+ *
+ * Called with sg->mm->mmap_lock in read.
+ */
+static int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr, unsigned long *pgt,
+ int *dat_protection, int *fake)
+{
+ unsigned long *table;
+ struct page *page;
+ int rc;
+
+ spin_lock(&sg->guest_table_lock);
+ table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */
I'd be happy if you could introduce an enum for the level argument in a
future series.
+ if (table && !(*table & _SEGMENT_ENTRY_INVALID)) {
+ /* Shadow page tables are full pages (pte+pgste) */
+ page = pfn_to_page(*table >> PAGE_SHIFT);
+ *pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE;
+ *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT);
+ *fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE);
+ rc = 0;
+ } else {
+ rc = -EAGAIN;
+ }
+ spin_unlock(&sg->guest_table_lock);
+ return rc;
+}
+
