From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Just have copy_page_{to,from}_iter() fall back to kmap_atomic +
copy_{to,from}_iter() + kunmap_atomic() in ITER_BVEC case. As
the matter of fact, that's what we want to do for any iov_iter
kind that isn't blocking - e.g. ITER_KVEC will also go that way
once we recognize it on iov_iter.c primitives level
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
mm/iov_iter.c | 60 ++++++++++++++++++++++++-----------------------------------
1 file changed, 24 insertions(+), 36 deletions(-)
diff --git a/mm/iov_iter.c b/mm/iov_iter.c
index 39ad713..17b7144 100644
--- a/mm/iov_iter.c
+++ b/mm/iov_iter.c
@@ -486,30 +486,33 @@ static size_t copy_from_iter_bvec(void *to, size_t bytes, struct iov_iter *i)
return wanted;
}
-static size_t copy_page_to_iter_bvec(struct page *page, size_t offset,
- size_t bytes, struct iov_iter *i)
+size_t copy_to_iter(void *addr, size_t bytes, struct iov_iter *i)
{
- void *kaddr = kmap_atomic(page);
- size_t wanted = copy_to_iter_bvec(kaddr + offset, bytes, i);
- kunmap_atomic(kaddr);
- return wanted;
+ if (i->type & ITER_BVEC)
+ return copy_to_iter_bvec(addr, bytes, i);
+ else
+ return copy_to_iter_iovec(addr, bytes, i);
}
+EXPORT_SYMBOL(copy_to_iter);
-static size_t copy_page_from_iter_bvec(struct page *page, size_t offset,
- size_t bytes, struct iov_iter *i)
+size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
{
- void *kaddr = kmap_atomic(page);
- size_t wanted = copy_from_iter_bvec(kaddr + offset, bytes, i);
- kunmap_atomic(kaddr);
- return wanted;
+ if (i->type & ITER_BVEC)
+ return copy_from_iter_bvec(addr, bytes, i);
+ else
+ return copy_from_iter_iovec(addr, bytes, i);
}
+EXPORT_SYMBOL(copy_from_iter);
size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes,
struct iov_iter *i)
{
- if (i->type & ITER_BVEC)
- return copy_page_to_iter_bvec(page, offset, bytes, i);
- else
+ if (i->type & (ITER_BVEC|ITER_KVEC)) {
+ void *kaddr = kmap_atomic(page);
+ size_t wanted = copy_to_iter(kaddr + offset, bytes, i);
+ kunmap_atomic(kaddr);
+ return wanted;
+ } else
return copy_page_to_iter_iovec(page, offset, bytes, i);
}
EXPORT_SYMBOL(copy_page_to_iter);
@@ -517,31 +520,16 @@ EXPORT_SYMBOL(copy_page_to_iter);
size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes,
struct iov_iter *i)
{
- if (i->type & ITER_BVEC)
- return copy_page_from_iter_bvec(page, offset, bytes, i);
- else
+ if (i->type & ITER_BVEC) {
+ void *kaddr = kmap_atomic(page);
+ size_t wanted = copy_from_iter(kaddr + offset, bytes, i);
+ kunmap_atomic(kaddr);
+ return wanted;
+ } else
return copy_page_from_iter_iovec(page, offset, bytes, i);
}
EXPORT_SYMBOL(copy_page_from_iter);
-size_t copy_to_iter(void *addr, size_t bytes, struct iov_iter *i)
-{
- if (i->type & ITER_BVEC)
- return copy_to_iter_bvec(addr, bytes, i);
- else
- return copy_to_iter_iovec(addr, bytes, i);
-}
-EXPORT_SYMBOL(copy_to_iter);
-
-size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
-{
- if (i->type & ITER_BVEC)
- return copy_from_iter_bvec(addr, bytes, i);
- else
- return copy_from_iter_iovec(addr, bytes, i);
-}
-EXPORT_SYMBOL(copy_from_iter);
-
size_t iov_iter_zero(size_t bytes, struct iov_iter *i)
{
if (unlikely(bytes > i->count))
--
2.1.3
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
