From: Ira Weiny <ira.we...@intel.com>
Now that there is a mechanism for users to safely take LONGTERM pins on
FS DAX pages. Remove the FS DAX exclusion from GUP with FOLL_LONGTERM.
Special processing remains in effect for CONFIG_CMA
---
mm/gup.c | 65 ++++++--------------------------------------------------
1 file changed, 6 insertions(+), 59 deletions(-)
diff --git a/mm/gup.c b/mm/gup.c
index 1ee17f2339f7..cf6863422cb9 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1324,26 +1324,6 @@ long get_user_pages_remote(struct task_struct *tsk,
struct mm_struct *mm,
}
EXPORT_SYMBOL(get_user_pages_remote);
-#if defined(CONFIG_FS_DAX) || defined (CONFIG_CMA)
-static bool check_dax_vmas(struct vm_area_struct **vmas, long nr_pages)
-{
- long i;
- struct vm_area_struct *vma_prev = NULL;
-
- for (i = 0; i < nr_pages; i++) {
- struct vm_area_struct *vma = vmas[i];
-
- if (vma == vma_prev)
- continue;
-
- vma_prev = vma;
-
- if (vma_is_fsdax(vma))
- return true;
- }
- return false;
-}
-
#ifdef CONFIG_CMA
static struct page *new_non_cma_page(struct page *page, unsigned long private)
{
@@ -1474,18 +1454,6 @@ static long check_and_migrate_cma_pages(struct
task_struct *tsk,
return nr_pages;
}
-#else
-static long check_and_migrate_cma_pages(struct task_struct *tsk,
- struct mm_struct *mm,
- unsigned long start,
- unsigned long nr_pages,
- struct page **pages,
- struct vm_area_struct **vmas,
- unsigned int gup_flags)
-{
- return nr_pages;
-}
-#endif
/*
* __gup_longterm_locked() is a wrapper for __get_user_pages_locked which
@@ -1499,49 +1467,28 @@ static long __gup_longterm_locked(struct task_struct
*tsk,
struct vm_area_struct **vmas,
unsigned int gup_flags)
{
- struct vm_area_struct **vmas_tmp = vmas;
unsigned long flags = 0;
- long rc, i;
+ long rc;
- if (gup_flags & FOLL_LONGTERM) {
- if (!pages)
- return -EINVAL;
-
- if (!vmas_tmp) {
- vmas_tmp = kcalloc(nr_pages,
- sizeof(struct vm_area_struct *),
- GFP_KERNEL);
- if (!vmas_tmp)
- return -ENOMEM;
- }
+ if (flags & FOLL_LONGTERM)
flags = memalloc_nocma_save();
- }
rc = __get_user_pages_locked(tsk, mm, start, nr_pages, pages,
- vmas_tmp, NULL, gup_flags);
+ vmas, NULL, gup_flags);
if (gup_flags & FOLL_LONGTERM) {
memalloc_nocma_restore(flags);
if (rc < 0)
goto out;
- if (check_dax_vmas(vmas_tmp, rc)) {
- for (i = 0; i < rc; i++)
- put_page(pages[i]);
- rc = -EOPNOTSUPP;
- goto out;
- }
-
rc = check_and_migrate_cma_pages(tsk, mm, start, rc, pages,
- vmas_tmp, gup_flags);
+ vmas, gup_flags);
}
out:
- if (vmas_tmp != vmas)
- kfree(vmas_tmp);
return rc;
}
-#else /* !CONFIG_FS_DAX && !CONFIG_CMA */
+#else /* !CONFIG_CMA */
static __always_inline long __gup_longterm_locked(struct task_struct *tsk,
struct mm_struct *mm,
unsigned long start,
@@ -1553,7 +1500,7 @@ static __always_inline long __gup_longterm_locked(struct
task_struct *tsk,
return __get_user_pages_locked(tsk, mm, start, nr_pages, pages, vmas,
NULL, flags);
}
-#endif /* CONFIG_FS_DAX || CONFIG_CMA */
+#endif /* CONFIG_CMA */
/*
* This is the same as get_user_pages_remote(), just with a
--
2.20.1
