diff options
| author | Christoph Hellwig <hch@lst.de> | 2021-08-11 14:44:27 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-08-13 14:17:39 -0600 |
| commit | 6177b56c96ff3b5e23d47f6b6c8630f31145da93 (patch) | |
| tree | 37aa161a899ba695984ca13a3fc8d4ec0cc8382e /drivers/block | |
| parent | 7bdc00cf7e369b3be17f26e5643da28de98d9d6d (diff) | |
nbd: refactor device search and allocation in nbd_genl_connect
Use idr_for_each_entry instead of the awkward callback to find an
existing device for the index == -1 case, and de-duplicate the device
allocation if no existing device was found.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210811124428.2368491-6-hch@lst.de
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/nbd.c | 45 |
1 files changed, 14 insertions, 31 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index a81b95c66dbf..8c0e334bdfbf 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1767,18 +1767,6 @@ out: return ERR_PTR(err); } -static int find_free_cb(int id, void *ptr, void *data) -{ - struct nbd_device *nbd = ptr; - struct nbd_device **found = data; - - if (!refcount_read(&nbd->config_refs)) { - *found = nbd; - return 1; - } - return 0; -} - /* Netlink interface. */ static const struct nla_policy nbd_attr_policy[NBD_ATTR_MAX + 1] = { [NBD_ATTR_INDEX] = { .type = NLA_U32 }, @@ -1848,31 +1836,26 @@ static int nbd_genl_connect(struct sk_buff *skb, struct genl_info *info) again: mutex_lock(&nbd_index_mutex); if (index == -1) { - ret = idr_for_each(&nbd_index_idr, &find_free_cb, &nbd); - if (ret == 0) { - nbd = nbd_dev_add(-1); - if (IS_ERR(nbd)) { - mutex_unlock(&nbd_index_mutex); - printk(KERN_ERR "nbd: failed to add new device\n"); - return PTR_ERR(nbd); + struct nbd_device *tmp; + int id; + + idr_for_each_entry(&nbd_index_idr, tmp, id) { + if (!refcount_read(&tmp->config_refs)) { + nbd = tmp; + break; } } } else { nbd = idr_find(&nbd_index_idr, index); - if (!nbd) { - nbd = nbd_dev_add(index); - if (IS_ERR(nbd)) { - mutex_unlock(&nbd_index_mutex); - printk(KERN_ERR "nbd: failed to add new device\n"); - return PTR_ERR(nbd); - } - } } + if (!nbd) { - printk(KERN_ERR "nbd: couldn't find device at index %d\n", - index); - mutex_unlock(&nbd_index_mutex); - return -EINVAL; + nbd = nbd_dev_add(index); + if (IS_ERR(nbd)) { + mutex_unlock(&nbd_index_mutex); + pr_err("nbd: failed to add new device\n"); + return PTR_ERR(nbd); + } } if (test_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags) && |