[ 209/221] rbd: remove snapshots on error in rbd_add()

Greg Kroah-Hartman
2013-01-15T22:40:32Z

From: Alex Elder <elder@inktank.com>

(cherry picked from commit 41f38c2b2f8b66b176a0e548ef06294343a7bfa2)

If rbd_dev_snaps_update() has ever been called for an rbd device
structure there could be snapshot structures on its snaps list.
In rbd_add(), this function is called but a subsequent error
path neglected to clean up any of these snapshots.

Add a call to rbd_remove_all_snaps() in the appropriate spot to
remedy this. Change a couple of error labels to be a little
clearer while there.

Drop the leading underscores from the function name; there's nothing
special about that function that they might signify. As suggested
in review, the leading underscores in __rbd_remove_snap_dev() have
been removed as well.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/block/rbd.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -221,7 +221,7 @@ static int rbd_dev_snaps_update(struct r
static int rbd_dev_snaps_register(struct rbd_device *rbd_dev);

static void rbd_dev_release(struct device *dev);
-static void __rbd_remove_snap_dev(struct rbd_snap *snap);
+static void rbd_remove_snap_dev(struct rbd_snap *snap);

static ssize_t rbd_add(struct bus_type *bus, const char *buf,
size_t count);
@@ -1710,13 +1710,13 @@ static int rbd_read_header(struct rbd_de
return ret;
}

-static void __rbd_remove_all_snaps(struct rbd_device *rbd_dev)
+static void rbd_remove_all_snaps(struct rbd_device *rbd_dev)
{
struct rbd_snap *snap;
struct rbd_snap *next;

list_for_each_entry_safe(snap, next, &rbd_dev->snaps, node)
- __rbd_remove_snap_dev(snap);
+ rbd_remove_snap_dev(snap);
}

/*
@@ -2060,7 +2060,7 @@ static bool rbd_snap_registered(struct r
return ret;
}

-static void __rbd_remove_snap_dev(struct rbd_snap *snap)
+static void rbd_remove_snap_dev(struct rbd_snap *snap)
{
list_del(&snap->node);
if (device_is_registered(&snap->dev))
@@ -2442,7 +2442,7 @@ static int rbd_dev_snaps_update(struct r

if (rbd_dev->mapping.snap_id == snap->id)
rbd_dev->mapping.snap_exists = false;
- __rbd_remove_snap_dev(snap);
+ rbd_remove_snap_dev(snap);
dout("%ssnap id %llu has been removed\n",
rbd_dev->mapping.snap_id == snap->id ?
"mapped " : "",
@@ -3053,11 +3053,11 @@ static ssize_t rbd_add(struct bus_type *
/* no need to lock here, as rbd_dev is not registered yet */
rc = rbd_dev_snaps_update(rbd_dev);
if (rc)
- goto err_out_header;
+ goto err_out_probe;

rc = rbd_dev_set_mapping(rbd_dev, snap_name);
if (rc)
- goto err_out_header;
+ goto err_out_snaps;

/* generate unique id: find highest unique id, add one */
rbd_dev_id_get(rbd_dev);
@@ -3121,7 +3121,9 @@ err_out_blkdev:
unregister_blkdev(rbd_dev->major, rbd_dev->name);
err_out_id:
rbd_dev_id_put(rbd_dev);
-err_out_header:
+err_out_snaps:
+ rbd_remove_all_snaps(rbd_dev);
+err_out_probe:
rbd_header_free(&rbd_dev->header);
err_out_client:
kfree(rbd_dev->header_name);
@@ -3219,7 +3221,7 @@ static ssize_t rbd_remove(struct bus_typ
goto done;
}

- __rbd_remove_all_snaps(rbd_dev);
+ rbd_remove_all_snaps(rbd_dev);
rbd_bus_del_dev(rbd_dev);