diff options
author | Sagi Grimberg <sagi@lightbitslabs.com> | 2018-12-04 04:52:09 +0300 |
---|---|---|
committer | Christoph Hellwig <hch@lst.de> | 2018-12-13 11:58:54 +0300 |
commit | d05f443554b3c7dc6d46e3ba9c3c4de468875d4f (patch) | |
tree | 6bc94110dc8dd6ea1540ec26b6b4f6c3029ea0f0 /lib | |
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>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/iov_iter.c | 16 |
1 files changed, 16 insertions, 0 deletions
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; |