linux/drivers/target
Johannes Berg 053c095a82 netlink: make nlmsg_end() and genlmsg_end() void
Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-18 01:03:45 -05:00
..
iscsi iscsi-target: Fix typos in enum cmd_flags_table 2015-01-09 15:25:58 -08:00
loopback SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
sbp scsi: remove MSG_*_TAG defines 2014-12-04 09:58:33 +01:00
tcm_fc scsi: remove MSG_*_TAG defines 2014-12-04 09:58:33 +01:00
Kconfig target: Add a user-passthrough backstore 2014-10-03 11:15:20 -07:00
Makefile target: Add a user-passthrough backstore 2014-10-03 11:15:20 -07:00
target_core_alua.c scsi: rename SERVICE_ACTION_IN to SERVICE_ACTION_IN_16 2014-11-24 20:01:40 +01:00
target_core_alua.h target_core_alua: Referrals configfs integration 2014-01-09 21:48:35 -08:00
target_core_configfs.c target: Drop left-over internal dev attribute code 2014-12-01 21:36:21 -08:00
target_core_device.c target: Drop left-over fabric_max_sectors attribute 2015-01-09 15:22:05 -08:00
target_core_fabric_configfs.c target: Change core_dev_del_lun to take a se_lun instead of unpacked_lun 2014-10-01 14:38:48 -07:00
target_core_fabric_lib.c target: fix pr_out length in iscsi_parse_pr_out_transport_id 2014-09-17 15:17:35 -07:00
target_core_file.c target: Drop left-over fabric_max_sectors attribute 2015-01-09 15:22:05 -08:00
target_core_file.h Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-01-31 15:31:23 -08:00
target_core_hba.c target: Move dev_cit to struct se_subsystem_api 2014-12-01 21:35:22 -08:00
target_core_iblock.c target: Drop left-over fabric_max_sectors attribute 2015-01-09 15:22:05 -08:00
target_core_iblock.h
target_core_internal.h target: Add EXPORT_SYMBOL for existing se_dev_set_* 2014-12-01 21:36:02 -08:00
target_core_pr.c target: Allow Write Exclusive non-reservation holders to READ 2015-01-09 15:22:14 -08:00
target_core_pr.h target: Fix APTPL metadata handling for dynamic MappedLUNs 2014-10-04 05:40:19 +00:00
target_core_pscsi.c SCSI for-linus on 20141220 2014-12-20 13:42:57 -08:00
target_core_pscsi.h
target_core_rd.c target: Drop left-over fabric_max_sectors attribute 2015-01-09 15:22:05 -08:00
target_core_rd.h target/rd: Add support for protection SGL setup + release 2014-01-19 02:22:05 +00:00
target_core_sbc.c target: Drop arbitrary maximum I/O size limit 2015-01-09 15:21:40 -08:00
target_core_spc.c target: Drop arbitrary maximum I/O size limit 2015-01-09 15:21:40 -08:00
target_core_stat.c target: Convert se_device statistics to atomic_long_t 2013-11-13 18:34:55 -08:00
target_core_tmr.c target: simplify core_tmr_abort_task 2014-10-01 14:39:10 -07:00
target_core_tpg.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-10-21 13:06:38 -07:00
target_core_transport.c Merge remote-tracking branch 'scsi-queue/drivers-for-3.19' into for-linus 2014-12-18 05:56:29 -08:00
target_core_ua.c target: encapsulate smp_mb__after_atomic() 2014-10-01 14:39:06 -07:00
target_core_ua.h target: target_core_ua_h: Add #define of include guard 2014-09-15 14:27:43 -07:00
target_core_user.c netlink: make nlmsg_end() and genlmsg_end() void 2015-01-18 01:03:45 -05:00
target_core_xcopy.c treewide: fix typo in printk and Kconfig 2014-11-20 14:56:11 +01:00
target_core_xcopy.h