2023-09-23 04:00:43

by David Howells

[permalink] [raw]
Subject: [PATCH v6 10/13] iov_iter, net: Move csum_and_copy_to/from_iter() to net/

Move csum_and_copy_to/from_iter() to net code now that the iteration
framework can be #included.

Signed-off-by: David Howells <[email protected]>
---
include/linux/skbuff.h | 25 ++++++++++++
include/linux/uio.h | 18 ---------
lib/iov_iter.c | 89 ------------------------------------------
net/core/datagram.c | 50 +++++++++++++++++++++++-
net/core/skbuff.c | 33 ++++++++++++++++
5 files changed, 107 insertions(+), 108 deletions(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 4174c4b82d13..d0656cc11c16 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -3679,6 +3679,31 @@ static inline int __must_check skb_put_padto(struct sk_buff *skb, unsigned int l
return __skb_put_padto(skb, len, true);
}

+static inline __wsum csum_and_memcpy(void *to, const void *from, size_t len,
+ __wsum sum, size_t off)
+{
+ __wsum next = csum_partial_copy_nocheck(from, to, len);
+ return csum_block_add(sum, next, off);
+}
+
+struct csum_state {
+ __wsum csum;
+ size_t off;
+};
+
+size_t csum_and_copy_from_iter(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;
+}
+
static inline int skb_add_data(struct sk_buff *skb,
struct iov_iter *from, int copy)
{
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 65d9143f83c8..0a5426c97e02 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -338,24 +338,6 @@ iov_iter_npages_cap(struct iov_iter *i, int maxpages, size_t max_bytes)
return npages;
}

-struct csum_state {
- __wsum csum;
- size_t off;
-};
-
-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);
-
-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);

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 943aa3cfd7b3..fef934a8745d 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -10,7 +10,6 @@
#include <linux/vmalloc.h>
#include <linux/splice.h>
#include <linux/compat.h>
-#include <net/checksum.h>
#include <linux/scatterlist.h>
#include <linux/instrumented.h>
#include <linux/iov_iter.h>
@@ -179,13 +178,6 @@ void iov_iter_init(struct iov_iter *i, unsigned int direction,
}
EXPORT_SYMBOL(iov_iter_init);

-static __wsum csum_and_memcpy(void *to, const void *from, size_t len,
- __wsum sum, size_t off)
-{
- __wsum next = csum_partial_copy_nocheck(from, to, len);
- return csum_block_add(sum, next, off);
-}
-
size_t _copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
{
if (WARN_ON_ONCE(i->data_source))
@@ -1101,87 +1093,6 @@ ssize_t iov_iter_get_pages_alloc2(struct iov_iter *i,
}
EXPORT_SYMBOL(iov_iter_get_pages_alloc2);

-static __always_inline
-size_t copy_from_user_iter_csum(void __user *iter_from, size_t progress,
- size_t len, void *to, void *priv2)
-{
- __wsum next, *csum = priv2;
-
- next = csum_and_copy_from_user(iter_from, to + progress, len);
- *csum = csum_block_add(*csum, next, progress);
- return next ? 0 : len;
-}
-
-static __always_inline
-size_t memcpy_from_iter_csum(void *iter_from, size_t progress,
- size_t len, void *to, void *priv2)
-{
- __wsum *csum = priv2;
-
- *csum = csum_and_memcpy(to + progress, iter_from, len, *csum, progress);
- return 0;
-}
-
-size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,
- struct iov_iter *i)
-{
- if (WARN_ON_ONCE(!i->data_source))
- return 0;
- return iterate_and_advance2(i, bytes, addr, csum,
- copy_from_user_iter_csum,
- memcpy_from_iter_csum);
-}
-EXPORT_SYMBOL(csum_and_copy_from_iter);
-
-static __always_inline
-size_t copy_to_user_iter_csum(void __user *iter_to, size_t progress,
- size_t len, void *from, void *priv2)
-{
- __wsum next, *csum = priv2;
-
- next = csum_and_copy_to_user(from + progress, iter_to, len);
- *csum = csum_block_add(*csum, next, progress);
- return next ? 0 : len;
-}
-
-static __always_inline
-size_t memcpy_to_iter_csum(void *iter_to, size_t progress,
- size_t len, void *from, void *priv2)
-{
- __wsum *csum = priv2;
-
- *csum = csum_and_memcpy(iter_to, from + progress, len, *csum, progress);
- return 0;
-}
-
-size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *_csstate,
- struct iov_iter *i)
-{
- struct csum_state *csstate = _csstate;
- __wsum sum;
-
- if (WARN_ON_ONCE(i->data_source))
- return 0;
- if (unlikely(iov_iter_is_discard(i))) {
- // can't use csum_memcpy() for that one - data is not copied
- csstate->csum = csum_block_add(csstate->csum,
- csum_partial(addr, bytes, 0),
- csstate->off);
- csstate->off += bytes;
- return bytes;
- }
-
- sum = csum_shift(csstate->csum, csstate->off);
-
- bytes = iterate_and_advance2(i, bytes, (void *)addr, &sum,
- copy_to_user_iter_csum,
- memcpy_to_iter_csum);
- csstate->csum = csum_shift(sum, csstate->off);
- csstate->off += bytes;
- return bytes;
-}
-EXPORT_SYMBOL(csum_and_copy_to_iter);
-
size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp,
struct iov_iter *i)
{
diff --git a/net/core/datagram.c b/net/core/datagram.c
index 176eb5834746..37c89d0933b7 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -50,7 +50,7 @@
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
-#include <linux/uio.h>
+#include <linux/iov_iter.h>
#include <linux/indirect_call_wrapper.h>

#include <net/protocol.h>
@@ -716,6 +716,54 @@ int zerocopy_sg_from_iter(struct sk_buff *skb, struct iov_iter *from)
}
EXPORT_SYMBOL(zerocopy_sg_from_iter);

+static __always_inline
+size_t copy_to_user_iter_csum(void __user *iter_to, size_t progress,
+ size_t len, void *from, void *priv2)
+{
+ __wsum next, *csum = priv2;
+
+ next = csum_and_copy_to_user(from + progress, iter_to, len);
+ *csum = csum_block_add(*csum, next, progress);
+ return next ? 0 : len;
+}
+
+static __always_inline
+size_t memcpy_to_iter_csum(void *iter_to, size_t progress,
+ size_t len, void *from, void *priv2)
+{
+ __wsum *csum = priv2;
+
+ *csum = csum_and_memcpy(iter_to, from + progress, len, *csum, progress);
+ return 0;
+}
+
+static size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *_csstate,
+ struct iov_iter *i)
+{
+ struct csum_state *csstate = _csstate;
+ __wsum sum;
+
+ if (WARN_ON_ONCE(i->data_source))
+ return 0;
+ if (unlikely(iov_iter_is_discard(i))) {
+ // can't use csum_memcpy() for that one - data is not copied
+ csstate->csum = csum_block_add(csstate->csum,
+ csum_partial(addr, bytes, 0),
+ csstate->off);
+ csstate->off += bytes;
+ return bytes;
+ }
+
+ sum = csum_shift(csstate->csum, csstate->off);
+
+ bytes = iterate_and_advance2(i, bytes, (void *)addr, &sum,
+ copy_to_user_iter_csum,
+ memcpy_to_iter_csum);
+ csstate->csum = csum_shift(sum, csstate->off);
+ csstate->off += bytes;
+ return bytes;
+}
+
/**
* skb_copy_and_csum_datagram - Copy datagram to an iovec iterator
* and update a checksum.
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 4eaf7ed0d1f4..5dbdfce2d05f 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -62,6 +62,7 @@
#include <linux/if_vlan.h>
#include <linux/mpls.h>
#include <linux/kcov.h>
+#include <linux/iov_iter.h>

#include <net/protocol.h>
#include <net/dst.h>
@@ -6931,3 +6932,35 @@ ssize_t skb_splice_from_iter(struct sk_buff *skb, struct iov_iter *iter,
return spliced ?: ret;
}
EXPORT_SYMBOL(skb_splice_from_iter);
+
+static __always_inline
+size_t memcpy_from_iter_csum(void *iter_from, size_t progress,
+ size_t len, void *to, void *priv2)
+{
+ __wsum *csum = priv2;
+
+ *csum = csum_and_memcpy(to + progress, iter_from, len, *csum, progress);
+ return 0;
+}
+
+static __always_inline
+size_t copy_from_user_iter_csum(void __user *iter_from, size_t progress,
+ size_t len, void *to, void *priv2)
+{
+ __wsum next, *csum = priv2;
+
+ next = csum_and_copy_from_user(iter_from, to + progress, len);
+ *csum = csum_block_add(*csum, next, progress);
+ return next ? 0 : len;
+}
+
+size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum,
+ struct iov_iter *i)
+{
+ if (WARN_ON_ONCE(!i->data_source))
+ return 0;
+ return iterate_and_advance2(i, bytes, addr, csum,
+ copy_from_user_iter_csum,
+ memcpy_from_iter_csum);
+}
+EXPORT_SYMBOL(csum_and_copy_from_iter);