summaryrefslogtreecommitdiff
path: root/drivers
diff options
context:
space:
mode:
authorPaul Clements <paul.clements@steeleye.com>2013-07-03 15:09:04 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-03-11 16:10:06 -0700
commit50e97121b728014dfbc34f07d1ac5a507466a2b7 (patch)
tree09bd01313569381c361418a1fb7715f2c883f7aa /drivers
parentb0f9634dcc55be0ad7cfbc96c790bad780bd463d (diff)
nbd: correct disconnect behavior
commit c378f70adbc1bbecd9e6db145019f14b2f688c7c upstream. Currently, when a disconnect is requested by the user (via NBD_DISCONNECT ioctl) the return from NBD_DO_IT is undefined (it is usually one of several error codes). This means that nbd-client does not know if a manual disconnect was performed or whether a network error occurred. Because of this, nbd-client's persist mode (which tries to reconnect after error, but not after manual disconnect) does not always work correctly. This change fixes this by causing NBD_DO_IT to always return 0 if a user requests a disconnect. This means that nbd-client can correctly either persist the connection (if an error occurred) or disconnect (if the user requested it). Signed-off-by: Paul Clements <paul.clements@steeleye.com> Acked-by: Rob Landley <rob@landley.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [xr: Backported to 3.4: adjust context] Signed-off-by: Rui Xiang <rui.xiang@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/block/nbd.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 386d40e3cf48..d724da52153b 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -590,8 +590,11 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
nbd_cmd(&sreq) = NBD_CMD_DISC;
if (!nbd->sock)
return -EINVAL;
+
+ nbd->disconnect = 1;
+
nbd_send_req(nbd, &sreq);
- return 0;
+ return 0;
}
case NBD_CLEAR_SOCK: {
@@ -620,6 +623,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
nbd->sock = SOCKET_I(inode);
if (max_part > 0)
bdev->bd_invalidated = 1;
+ nbd->disconnect = 0; /* we're connected now */
return 0;
} else {
fput(file);
@@ -691,6 +695,8 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
set_capacity(nbd->disk, 0);
if (max_part > 0)
ioctl_by_bdev(bdev, BLKRRPART, 0);
+ if (nbd->disconnect) /* user requested, ignore socket errors */
+ return 0;
return nbd->harderror;
}