/*
* ksmd, and unmerge_and_remove_all_rmap_items(), must not touch an mm's
* page tables after it has passed through ksm_exit() - which, if necessary,
- * takes mmap_sem briefly to serialize against them. ksm_exit() does not set
+ * takes mmap_lock briefly to serialize against them. ksm_exit() does not set
* a special flag: they can just back out as soon as mm_users goes to zero.
* ksm_test_exit() is used throughout to make this test for exit: in some
* places for correctness, in some places just to avoid unnecessary work.
*/
put_anon_vma(rmap_item->anon_vma);
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
vma = find_mergeable_vma(mm, addr);
if (vma)
break_ksm(vma, addr);
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
}
static struct page *get_mergeable_page(struct rmap_item *rmap_item)
struct vm_area_struct *vma;
struct page *page;
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
vma = find_mergeable_vma(mm, addr);
if (!vma)
goto out;
out:
page = NULL;
}
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
return page;
}
* Move the old stable node to the second dimension
* queued in the hlist_dup. The invariant is that all
* dup stable_nodes in the chain->hlist point to pages
- * that are wrprotected and have the exact same
+ * that are write protected and have the exact same
* content.
*/
stable_node_chain_add_dup(dup, chain);
* Though it's very tempting to unmerge rmap_items from stable tree rather
* than check every pte of a given vma, the locking doesn't quite work for
* that - an rmap_item is assigned to the stable tree after inserting ksm
- * page and upping mmap_sem. Nor does it fit with the way we skip dup'ing
+ * page and upping mmap_lock. Nor does it fit with the way we skip dup'ing
* rmap_items from parent to child at fork time (so as not to waste time
* if exit comes before the next scan reaches it).
*
for (mm_slot = ksm_scan.mm_slot;
mm_slot != &ksm_mm_head; mm_slot = ksm_scan.mm_slot) {
mm = mm_slot->mm;
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (ksm_test_exit(mm))
break;
}
remove_trailing_rmap_items(mm_slot, &mm_slot->rmap_list);
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
spin_lock(&ksm_mmlist_lock);
ksm_scan.mm_slot = list_entry(mm_slot->mm_list.next,
return 0;
error:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
spin_lock(&ksm_mmlist_lock);
ksm_scan.mm_slot = &ksm_mm_head;
spin_unlock(&ksm_mmlist_lock);
/*
* No need to check ksm_use_zero_pages here: we can only have a
- * zero_page here if ksm_use_zero_pages was enabled alreaady.
+ * zero_page here if ksm_use_zero_pages was enabled already.
*/
if (!is_zero_pfn(page_to_pfn(kpage))) {
get_page(kpage);
struct vm_area_struct *vma;
int err = -EFAULT;
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
vma = find_mergeable_vma(mm, rmap_item->address);
if (!vma)
goto out;
/* Unstable nid is in union with stable anon_vma: remove first */
remove_rmap_item_from_tree(rmap_item);
- /* Must get reference to anon_vma while still holding mmap_sem */
+ /* Must get reference to anon_vma while still holding mmap_lock */
rmap_item->anon_vma = vma->anon_vma;
get_anon_vma(vma->anon_vma);
out:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
return err;
}
* continue. All KSM pages belonging to the
* stable_node dups in a stable_node chain
* have the same content and they're
- * wrprotected at all times. Any will work
+ * write protected at all times. Any will work
* fine to continue the walk.
*/
tree_page = get_ksm_page(stable_node_any,
* continue. All KSM pages belonging to the
* stable_node dups in a stable_node chain
* have the same content and they're
- * wrprotected at all times. Any will work
+ * write protected at all times. Any will work
* fine to continue the walk.
*/
tree_page = get_ksm_page(stable_node_any,
* duplicate. page_migration could break later if rmap breaks,
* so we can as well crash here. We really need to check for
* rmap_hlist_len == STABLE_NODE_CHAIN, but we can as well check
- * for other negative values as an undeflow if detected here
+ * for other negative values as an underflow if detected here
* for the first time (and not when decreasing rmap_hlist_len)
* would be sign of memory corruption in the stable_node.
*/
if (ksm_use_zero_pages && (checksum == zero_checksum)) {
struct vm_area_struct *vma;
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
vma = find_mergeable_vma(mm, rmap_item->address);
if (vma) {
err = try_to_merge_one_page(vma, page,
*/
err = 0;
}
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
/*
* In case of failure, the page was not really empty, so we
* need to continue. Otherwise we're done.
}
mm = slot->mm;
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
if (ksm_test_exit(mm))
vma = NULL;
else
ksm_scan.address += PAGE_SIZE;
} else
put_page(*page);
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
return rmap_item;
}
put_page(*page);
struct mm_slot, mm_list);
if (ksm_scan.address == 0) {
/*
- * We've completed a full scan of all vmas, holding mmap_sem
+ * We've completed a full scan of all vmas, holding mmap_lock
* throughout, and found no VM_MERGEABLE: so do the same as
* __ksm_exit does to remove this mm from all our lists now.
* This applies either when cleaning up after __ksm_exit
* (but beware: we can reach here even before __ksm_exit),
* or when all VM_MERGEABLE areas have been unmapped (and
- * mmap_sem then protects against race with MADV_MERGEABLE).
+ * mmap_lock then protects against race with MADV_MERGEABLE).
*/
hash_del(&slot->link);
list_del(&slot->mm_list);
free_mm_slot(slot);
clear_bit(MMF_VM_MERGEABLE, &mm->flags);
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
mmdrop(mm);
} else {
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
/*
- * up_read(&mm->mmap_sem) first because after
+ * mmap_read_unlock(mm) first because after
* spin_unlock(&ksm_mmlist_lock) run, the "mm" may
* already have been freed under us by __ksm_exit()
* because the "mm_slot" is still hashed and
* This process is exiting: if it's straightforward (as is the
* case when ksmd was never running), free mm_slot immediately.
* But if it's at the cursor or has rmap_items linked to it, use
- * mmap_sem to synchronize with any break_cows before pagetables
+ * mmap_lock to synchronize with any break_cows before pagetables
* are freed, and leave the mm_slot on the list for ksmd to free.
* Beware: ksm may already have noticed it exiting and freed the slot.
*/
clear_bit(MMF_VM_MERGEABLE, &mm->flags);
mmdrop(mm);
} else if (mm_slot) {
- down_write(&mm->mmap_sem);
- up_write(&mm->mmap_sem);
+ mmap_write_lock(mm);
+ mmap_write_unlock(mm);
}
}