iov_iter: switch ..._full() variants of primitives to use of iov_iter_revert()

Use corresponding plain variants, revert on short copy.  That's the way it
should've been done from the very beginning, except that we didn't have
iov_iter_revert() back then...

[fixed another braino caught by Qian Cai <quic_qiancai@quicinc.com>]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2021-04-29 21:16:56 -04:00
parent 3b3fc051cd
commit 4b6c132b7d
2 changed files with 21 additions and 115 deletions

View file

@ -132,9 +132,7 @@ size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes,
size_t _copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i);
size_t _copy_from_iter(void *addr, size_t bytes, struct iov_iter *i);
bool _copy_from_iter_full(void *addr, size_t bytes, struct iov_iter *i);
size_t _copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i);
bool _copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i);
static __always_inline __must_check
size_t copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
@ -157,10 +155,11 @@ size_t copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
static __always_inline __must_check
bool copy_from_iter_full(void *addr, size_t bytes, struct iov_iter *i)
{
if (unlikely(!check_copy_size(addr, bytes, false)))
return false;
else
return _copy_from_iter_full(addr, bytes, i);
size_t copied = copy_from_iter(addr, bytes, i);
if (likely(copied == bytes))
return true;
iov_iter_revert(i, copied);
return false;
}
static __always_inline __must_check
@ -175,10 +174,11 @@ size_t copy_from_iter_nocache(void *addr, size_t bytes, struct iov_iter *i)
static __always_inline __must_check
bool copy_from_iter_full_nocache(void *addr, size_t bytes, struct iov_iter *i)
{
if (unlikely(!check_copy_size(addr, bytes, false)))
return false;
else
return _copy_from_iter_full_nocache(addr, bytes, i);
size_t copied = copy_from_iter_nocache(addr, bytes, i);
if (likely(copied == bytes))
return true;
iov_iter_revert(i, copied);
return false;
}
#ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
@ -278,7 +278,17 @@ struct csum_state {
size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csstate, struct iov_iter *i);
size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
static __always_inline __must_check
bool csum_and_copy_from_iter_full(void *addr, size_t bytes,
__wsum *csum, struct iov_iter *i)
{
size_t copied = csum_and_copy_from_iter(addr, bytes, csum, i);
if (likely(copied == bytes))
return true;
iov_iter_revert(i, copied);
return false;
}
size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp,
struct iov_iter *i);