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authorAl Viro <viro@zeniv.linux.org.uk>2015-11-12 05:09:35 -0500
committerAl Viro <viro@zeniv.linux.org.uk>2016-12-26 21:35:13 -0500
commitc9f2b6aeb92286f15ffc80d2ba16bc24e530f560 (patch)
tree8307a262414211afe5ab48747ef4bdee7ff9a285 /drivers/block/nbd.c
parentc1696cab700588f8493df7b51e096abf5bfb1d40 (diff)
[nbd] pass iov_iter to nbd_xmit()
... and don't mess with kmap() - just use BVEC_ITER for those parts. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'drivers/block/nbd.c')
-rw-r--r--drivers/block/nbd.c66
1 files changed, 27 insertions, 39 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 8e63caecdd00..3c2dbe412c02 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -209,13 +209,12 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
/*
* Send or receive packet.
*/
-static int sock_xmit(struct nbd_device *nbd, int index, int send, void *buf,
- int size, int msg_flags)
+static int sock_xmit(struct nbd_device *nbd, int index, int send,
+ struct iov_iter *iter, int msg_flags)
{
struct socket *sock = nbd->socks[index]->sock;
int result;
struct msghdr msg;
- struct kvec iov = {.iov_base = buf, .iov_len = size};
unsigned long pflags = current->flags;
if (unlikely(!sock)) {
@@ -225,8 +224,7 @@ static int sock_xmit(struct nbd_device *nbd, int index, int send, void *buf,
return -EINVAL;
}
- iov_iter_kvec(&msg.msg_iter, (send ? WRITE : READ) | ITER_KVEC,
- &iov, 1, size);
+ msg.msg_iter = *iter;
current->flags |= PF_MEMALLOC;
do {
@@ -254,28 +252,21 @@ static int sock_xmit(struct nbd_device *nbd, int index, int send, void *buf,
return result;
}
-static inline int sock_send_bvec(struct nbd_device *nbd, int index,
- struct bio_vec *bvec, int flags)
-{
- int result;
- void *kaddr = kmap(bvec->bv_page);
- result = sock_xmit(nbd, index, 1, kaddr + bvec->bv_offset,
- bvec->bv_len, flags);
- kunmap(bvec->bv_page);
- return result;
-}
-
/* always call with the tx_lock held */
static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
{
struct request *req = blk_mq_rq_from_pdu(cmd);
int result, flags;
- struct nbd_request request;
+ struct nbd_request request = {.magic = htonl(NBD_REQUEST_MAGIC)};
+ struct kvec iov = {.iov_base = &request, .iov_len = sizeof(request)};
+ struct iov_iter from;
unsigned long size = blk_rq_bytes(req);
struct bio *bio;
u32 type;
u32 tag = blk_mq_unique_tag(req);
+ iov_iter_kvec(&from, WRITE | ITER_KVEC, &iov, 1, sizeof(request));
+
if (req_op(req) == REQ_OP_DISCARD)
type = NBD_CMD_TRIM;
else if (req_op(req) == REQ_OP_FLUSH)
@@ -285,8 +276,6 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
else
type = NBD_CMD_READ;
- memset(&request, 0, sizeof(request));
- request.magic = htonl(NBD_REQUEST_MAGIC);
request.type = htonl(type);
if (type != NBD_CMD_FLUSH) {
request.from = cpu_to_be64((u64)blk_rq_pos(req) << 9);
@@ -297,7 +286,7 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
dev_dbg(nbd_to_dev(nbd), "request %p: sending control (%s@%llu,%uB)\n",
cmd, nbdcmd_to_ascii(type),
(unsigned long long)blk_rq_pos(req) << 9, blk_rq_bytes(req));
- result = sock_xmit(nbd, index, 1, &request, sizeof(request),
+ result = sock_xmit(nbd, index, 1, &from,
(type == NBD_CMD_WRITE) ? MSG_MORE : 0);
if (result <= 0) {
dev_err_ratelimited(disk_to_dev(nbd->disk),
@@ -322,7 +311,9 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
flags = MSG_MORE;
dev_dbg(nbd_to_dev(nbd), "request %p: sending %d bytes data\n",
cmd, bvec.bv_len);
- result = sock_send_bvec(nbd, index, &bvec, flags);
+ iov_iter_bvec(&from, ITER_BVEC | WRITE,
+ &bvec, 1, bvec.bv_len);
+ result = sock_xmit(nbd, index, 1, &from, flags);
if (result <= 0) {
dev_err(disk_to_dev(nbd->disk),
"Send data failed (result %d)\n",
@@ -343,17 +334,6 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index)
return 0;
}
-static inline int sock_recv_bvec(struct nbd_device *nbd, int index,
- struct bio_vec *bvec)
-{
- int result;
- void *kaddr = kmap(bvec->bv_page);
- result = sock_xmit(nbd, index, 0, kaddr + bvec->bv_offset,
- bvec->bv_len, MSG_WAITALL);
- kunmap(bvec->bv_page);
- return result;
-}
-
/* NULL returned = something went wrong, inform userspace */
static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index)
{
@@ -363,9 +343,12 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index)
struct request *req = NULL;
u16 hwq;
u32 tag;
+ struct kvec iov = {.iov_base = &reply, .iov_len = sizeof(reply)};
+ struct iov_iter to;
reply.magic = 0;
- result = sock_xmit(nbd, index, 0, &reply, sizeof(reply), MSG_WAITALL);
+ iov_iter_kvec(&to, READ | ITER_KVEC, &iov, 1, sizeof(reply));
+ result = sock_xmit(nbd, index, 0, &to, MSG_WAITALL);
if (result <= 0) {
if (!test_bit(NBD_DISCONNECTED, &nbd->runtime_flags) &&
!test_bit(NBD_DISCONNECT_REQUESTED, &nbd->runtime_flags))
@@ -405,7 +388,9 @@ static struct nbd_cmd *nbd_read_stat(struct nbd_device *nbd, int index)
struct bio_vec bvec;
rq_for_each_segment(bvec, req, iter) {
- result = sock_recv_bvec(nbd, index, &bvec);
+ iov_iter_bvec(&to, ITER_BVEC | READ,
+ &bvec, 1, bvec.bv_len);
+ result = sock_xmit(nbd, index, 0, &to, MSG_WAITALL);
if (result <= 0) {
dev_err(disk_to_dev(nbd->disk), "Receive data failed (result %d)\n",
result);
@@ -645,14 +630,17 @@ static void nbd_parse_flags(struct nbd_device *nbd, struct block_device *bdev)
static void send_disconnects(struct nbd_device *nbd)
{
- struct nbd_request request = {};
+ struct nbd_request request = {
+ .magic = htonl(NBD_REQUEST_MAGIC),
+ .type = htonl(NBD_CMD_DISC),
+ };
+ struct kvec iov = {.iov_base = &request, .iov_len = sizeof(request)};
+ struct iov_iter from;
int i, ret;
- request.magic = htonl(NBD_REQUEST_MAGIC);
- request.type = htonl(NBD_CMD_DISC);
-
for (i = 0; i < nbd->num_connections; i++) {
- ret = sock_xmit(nbd, i, 1, &request, sizeof(request), 0);
+ iov_iter_kvec(&from, WRITE | ITER_KVEC, &iov, 1, sizeof(request));
+ ret = sock_xmit(nbd, i, 1, &from, 0);
if (ret <= 0)
dev_err(disk_to_dev(nbd->disk),
"Send disconnect failed %d\n", ret);