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authorDavid Howells <dhowells@redhat.com>2018-10-19 23:57:56 (GMT)
committerDavid Howells <dhowells@redhat.com>2018-10-23 23:41:07 (GMT)
commitaa563d7bca6e882ec2bdae24603c8f016401a144 (patch)
tree874b10fc11da3178e4630f7a430e1b299d3b3806 /drivers/xen
parent00e23707442a75b404392cef1405ab4fd498de6b (diff)
iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator direction and use accessor functions to access them in most places. Convert a bunch of places to use switch-statements to access them rather then chains of bitwise-AND statements. This makes it easier to add further iterator types. Also, this can be more efficient as to implement a switch of small contiguous integers, the compiler can use ~50% fewer compare instructions than it has to use bitwise-and instructions. Further, cease passing the iterator type into the iterator setup function. The iterator function can set that itself. Only the direction is required. Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'drivers/xen')
-rw-r--r--drivers/xen/pvcalls-back.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c
index b1092fb..2e5d845 100644
--- a/drivers/xen/pvcalls-back.c
+++ b/drivers/xen/pvcalls-back.c
@@ -137,13 +137,13 @@ static void pvcalls_conn_back_read(void *opaque)
if (masked_prod < masked_cons) {
vec[0].iov_base = data->in + masked_prod;
vec[0].iov_len = wanted;
- iov_iter_kvec(&msg.msg_iter, ITER_KVEC|WRITE, vec, 1, wanted);
+ iov_iter_kvec(&msg.msg_iter, WRITE, vec, 1, wanted);
} else {
vec[0].iov_base = data->in + masked_prod;
vec[0].iov_len = array_size - masked_prod;
vec[1].iov_base = data->in;
vec[1].iov_len = wanted - vec[0].iov_len;
- iov_iter_kvec(&msg.msg_iter, ITER_KVEC|WRITE, vec, 2, wanted);
+ iov_iter_kvec(&msg.msg_iter, WRITE, vec, 2, wanted);
}
atomic_set(&map->read, 0);
@@ -195,13 +195,13 @@ static void pvcalls_conn_back_write(struct sock_mapping *map)
if (pvcalls_mask(prod, array_size) > pvcalls_mask(cons, array_size)) {
vec[0].iov_base = data->out + pvcalls_mask(cons, array_size);
vec[0].iov_len = size;
- iov_iter_kvec(&msg.msg_iter, ITER_KVEC|READ, vec, 1, size);
+ iov_iter_kvec(&msg.msg_iter, READ, vec, 1, size);
} else {
vec[0].iov_base = data->out + pvcalls_mask(cons, array_size);
vec[0].iov_len = array_size - pvcalls_mask(cons, array_size);
vec[1].iov_base = data->out;
vec[1].iov_len = size - vec[0].iov_len;
- iov_iter_kvec(&msg.msg_iter, ITER_KVEC|READ, vec, 2, size);
+ iov_iter_kvec(&msg.msg_iter, READ, vec, 2, size);
}
atomic_set(&map->write, 0);

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