diff options
| author | Sagi Grimberg <sagi@lightbitslabs.com> | 2018-12-03 17:52:09 -0800 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2018-12-13 09:58:54 +0100 |
| commit | d05f443554b3c7dc6d46e3ba9c3c4de468875d4f (patch) | |
| tree | 6bc94110dc8dd6ea1540ec26b6b4f6c3029ea0f0 | |
| parent | 950fcaecd5cc6c014bb96506fd0652a501c85276 (diff) | |
iov_iter: introduce hash_and_copy_to_iter helper
Allow consumers that want to use iov iterator helpers and also update
a predefined hash calculation online when copying data. This is useful
when copying incoming network buffers to a local iterator and calculate
a digest on the incoming stream. nvme-tcp host driver that will be
introduced in following patches is the first consumer via
skb_copy_and_hash_datagram_iter.
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sagi Grimberg <sagi@lightbitslabs.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
| -rw-r--r-- | include/linux/uio.h | 3 | ||||
| -rw-r--r-- | lib/iov_iter.c | 16 |
2 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h index 41d1f8d3313d..ecf584f6b82d 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -11,6 +11,7 @@ #include <linux/kernel.h> #include <linux/thread_info.h> +#include <crypto/hash.h> #include <uapi/linux/uio.h> struct page; @@ -269,6 +270,8 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count) size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump, 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); +size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp, + struct iov_iter *i); int import_iovec(int type, const struct iovec __user * uvector, unsigned nr_segs, unsigned fast_segs, diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 63a8999a234d..1928009f506e 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -6,6 +6,7 @@ #include <linux/vmalloc.h> #include <linux/splice.h> #include <net/checksum.h> +#include <linux/scatterlist.h> #define PIPE_PARANOIA /* for now */ @@ -1511,6 +1512,21 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump, } 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) +{ + struct ahash_request *hash = hashp; + struct scatterlist sg; + size_t copied; + + copied = copy_to_iter(addr, bytes, i); + sg_init_one(&sg, addr, copied); + ahash_request_set_crypt(hash, &sg, NULL, copied); + crypto_ahash_update(hash); + return copied; +} +EXPORT_SYMBOL(hash_and_copy_to_iter); + int iov_iter_npages(const struct iov_iter *i, int maxpages) { size_t size = i->count; |