>>> - * gmap_pte_op_fixup - force a page in and connect the gmap page table
>>> + * gmap_fixup - force memory in and connect the gmap table entry
>>> * @gmap: pointer to guest mapping meta data structure
>>> * @gaddr: virtual address in the guest address space
>>> * @vmaddr: address in the host process address space
>>> @@ -841,10 +851,10 @@ static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr,
>>> *
>>> * Returns 0 if the caller can retry __gmap_translate (might fail again),
>>> * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing
>>> - * up or connecting the gmap page table.
>>> + * up or connecting the gmap table entry.
>>> */
>>> -static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr,
>>> - unsigned long vmaddr, int prot)
>>> +static int gmap_fixup(struct gmap *gmap, unsigned long gaddr,
>>> + unsigned long vmaddr, int prot)
>>> {
>>> struct mm_struct *mm = gmap->mm;
>>> unsigned int fault_flags;
>>> @@ -892,8 +902,11 @@ static inline pmd_t *gmap_pmd_op_walk(struct gmap *gmap, unsigned long gaddr)
>>> return NULL;
>>> }
>>>
>>> - /* 4k page table entries are locked via the pte (pte_alloc_map_lock). */
>>> - if (!pmd_large(*pmdp))
>>> + /*
>>> + * Non-split 4k page table entries are locked via the pte
>>> + * (pte_alloc_map_lock).
>>> + */
>>> + if (!gmap_pmd_is_split(pmdp) && !pmd_large(*pmdp))
>>> spin_unlock(&gmap->guest_table_lock);
>>> return pmdp;
>>> }
>>> @@ -905,10 +918,77 @@ static inline pmd_t *gmap_pmd_op_walk(struct gmap *gmap, unsigned long gaddr)
>>> */
>>> static inline void gmap_pmd_op_end(struct gmap *gmap, pmd_t *pmdp)
>>> {
>>> - if (pmd_large(*pmdp))
>>> + if (pmd_large(*pmdp) || gmap_pmd_is_split(pmdp))
>>> spin_unlock(&gmap->guest_table_lock);
>>> }
>>>
>>> +static pte_t *gmap_pte_from_pmd(struct gmap *gmap, pmd_t *pmdp,
>>> + unsigned long addr, spinlock_t **ptl)
>>> +{
>>> + if (likely(!gmap_pmd_is_split(pmdp)))
>>> + return pte_alloc_map_lock(gmap->mm, pmdp, addr, ptl);
>>> +
>>> + *ptl = NULL;
>>> + return pte_offset_map(pmdp, addr);
>>> +}
>>> +
>>> +/**
>>> + * gmap_pmd_split_free - Free a split pmd's page table
>>> + * @pmdp The split pmd that we free of its page table
>>> + *
>>> + * If the userspace pmds are exchanged, we'll remove the gmap pmds as
>>> + * well, so we fault on them and link them again. We would leak
>>> + * memory, if we didn't free split pmds here.
>>> + */
>>> +static inline void gmap_pmd_split_free(pmd_t *pmdp)
>>> +{
>>> + unsigned long pgt = pmd_val(*pmdp) & _SEGMENT_ENTRY_ORIGIN;
>>> + struct page *page;
>>> +
>>> + if (gmap_pmd_is_split(pmdp)) {
>>
>> can this ever not be the case? This function is not used in this patch.
>
> Look into the next one.
Move it to the next one :)
--
Thanks,
David / dhildenb
