[PATCH 03/10] nbd: Remove 'harderror' and propagate error properly

Markus Pargmann
2015-07-27T07:13:21Z

Instead of a variable 'harderror' we can simply try to correctly
propagate errors to the userspace.

This patch removes the harderror variable and passes errors through
error pointers and nbd_do_it back to the userspace.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
---
drivers/block/nbd.c | 28 ++++++++++++++--------------
1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 2c3661e4d364..8bce05d0df5e 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -41,7 +41,6 @@

struct nbd_device {
int flags;
- int harderror; /* Code of hard error */
struct socket * sock; /* If == NULL, device is not ready, yet */
int magic;

@@ -329,26 +328,24 @@ static struct request *nbd_read_stat(struct nbd_device *nbd)
if (result <= 0) {
dev_err(disk_to_dev(nbd->disk),
"Receive control failed (result %d)\n", result);
- goto harderror;
+ return ERR_PTR(result);
}

if (ntohl(reply.magic) != NBD_REPLY_MAGIC) {
dev_err(disk_to_dev(nbd->disk), "Wrong magic (0x%lx)\n",
(unsigned long)ntohl(reply.magic));
- result = -EPROTO;
- goto harderror;
+ return ERR_PTR(-EPROTO);
}

req = nbd_find_request(nbd, *(struct request **)reply.handle);
if (IS_ERR(req)) {
result = PTR_ERR(req);
if (result != -ENOENT)
- goto harderror;
+ return ERR_PTR(result);

dev_err(disk_to_dev(nbd->disk), "Unexpected reply (%p)\n",
reply.handle);
- result = -EBADR;
- goto harderror;
+ return ERR_PTR(-EBADR);
}

if (ntohl(reply.error)) {
@@ -376,9 +373,6 @@ static struct request *nbd_read_stat(struct nbd_device *nbd)
}
}
return req;
-harderror:
- nbd->harderror = result;
- return NULL;
}

static ssize_t pid_show(struct device *dev,
@@ -413,8 +407,15 @@ static int nbd_do_it(struct nbd_device *nbd)

nbd->task_recv = current;

- while ((req = nbd_read_stat(nbd)) != NULL)
+ while (1) {
+ req = nbd_read_stat(nbd);
+ if (IS_ERR(req)) {
+ ret = PTR_ERR(req);
+ break;
+ }
+
nbd_end_request(nbd, req);
+ }

nbd->task_recv = NULL;

@@ -734,8 +735,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
kthread_stop(thread);

mutex_lock(&nbd->tx_lock);
- if (error)
- return error;
+
sock_shutdown(nbd);
sock = nbd->sock;
nbd->sock = NULL;
@@ -754,7 +754,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
blkdev_reread_part(bdev);
if (nbd->disconnect) /* user requested, ignore socket errors */
return 0;
- return nbd->harderror;
+ return error;
}

case NBD_CLEAR_QUE:
--
2.1.4