Commit Graph

590 Commits

Author SHA1 Message Date
dingtianhong d4cca39d90 tipc: avoid possible deadlock while enable and disable bearer
We met lockdep warning when enable and disable the bearer for commands such as:

tipc-config -netid=1234 -addr=1.1.3 -be=eth:eth0
tipc-config -netid=1234 -addr=1.1.3 -bd=eth:eth0

---------------------------------------------------

[  327.693595] ======================================================
[  327.693994] [ INFO: possible circular locking dependency detected ]
[  327.694519] 3.11.0-rc3-wwd-default #4 Tainted: G           O
[  327.694882] -------------------------------------------------------
[  327.695385] tipc-config/5825 is trying to acquire lock:
[  327.695754]  (((timer))#2){+.-...}, at: [<ffffffff8105be80>] del_timer_sync+0x0/0xd0
[  327.696018]
[  327.696018] but task is already holding lock:
[  327.696018]  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>] bearer_disable+  0xdd/0x120 [tipc]
[  327.696018]
[  327.696018] which lock already depends on the new lock.
[  327.696018]
[  327.696018]
[  327.696018] the existing dependency chain (in reverse order) is:
[  327.696018]
[  327.696018] -> #1 (&(&b_ptr->lock)->rlock){+.-...}:
[  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]        [<ffffffff814d65b1>] _raw_spin_lock_bh+0x41/0x80
[  327.696018]        [<ffffffffa02c5d48>] disc_timeout+0x18/0xd0 [tipc]
[  327.696018]        [<ffffffff8105b92a>] call_timer_fn+0xda/0x1e0
[  327.696018]        [<ffffffff8105bcd7>] run_timer_softirq+0x2a7/0x2d0
[  327.696018]        [<ffffffff8105379a>] __do_softirq+0x16a/0x2e0
[  327.696018]        [<ffffffff81053a35>] irq_exit+0xd5/0xe0
[  327.696018]        [<ffffffff81033005>] smp_apic_timer_interrupt+0x45/0x60
[  327.696018]        [<ffffffff814df4af>] apic_timer_interrupt+0x6f/0x80
[  327.696018]        [<ffffffff8100b70e>] arch_cpu_idle+0x1e/0x30
[  327.696018]        [<ffffffff810a039d>] cpu_idle_loop+0x1fd/0x280
[  327.696018]        [<ffffffff810a043e>] cpu_startup_entry+0x1e/0x20
[  327.696018]        [<ffffffff81031589>] start_secondary+0x89/0x90
[  327.696018]
[  327.696018] -> #0 (((timer))#2){+.-...}:
[  327.696018]        [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
[  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]        [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
[  327.696018]        [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
[  327.696018]        [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
[  327.696018]        [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
[  327.696018]        [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
[  327.696018]        [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
[  327.696018]        [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
[  327.696018]        [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
[  327.696018]        [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
[  327.696018]        [<ffffffff8143e617>] genl_rcv+0x27/0x40
[  327.696018]        [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
[  327.696018]        [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
[  327.696018]        [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
[  327.696018]        [<ffffffff813f7957>] sock_aio_write+0x107/0x120
[  327.696018]        [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
[  327.696018]        [<ffffffff8117fc56>] vfs_write+0x186/0x190
[  327.696018]        [<ffffffff811803e0>] SyS_write+0x60/0xb0
[  327.696018]        [<ffffffff814de852>] system_call_fastpath+0x16/0x1b
[  327.696018]
[  327.696018] other info that might help us debug this:
[  327.696018]
[  327.696018]  Possible unsafe locking scenario:
[  327.696018]
[  327.696018]        CPU0                    CPU1
[  327.696018]        ----                    ----
[  327.696018]   lock(&(&b_ptr->lock)->rlock);
[  327.696018]                                lock(((timer))#2);
[  327.696018]                                lock(&(&b_ptr->lock)->rlock);
[  327.696018]   lock(((timer))#2);
[  327.696018]
[  327.696018]  *** DEADLOCK ***
[  327.696018]
[  327.696018] 5 locks held by tipc-config/5825:
[  327.696018]  #0:  (cb_lock){++++++}, at: [<ffffffff8143e608>] genl_rcv+0x18/0x40
[  327.696018]  #1:  (genl_mutex){+.+.+.}, at: [<ffffffff8143ed66>] genl_rcv_msg+0xa6/0xd0
[  327.696018]  #2:  (config_mutex){+.+.+.}, at: [<ffffffffa02bf889>] tipc_cfg_do_cmd+0x39/ 0x550 [tipc]
[  327.696018]  #3:  (tipc_net_lock){++.-..}, at: [<ffffffffa02be738>] tipc_disable_bearer+ 0x18/0x60 [tipc]
[  327.696018]  #4:  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>]             bearer_disable+0xdd/0x120 [tipc]
[  327.696018]
[  327.696018] stack backtrace:
[  327.696018] CPU: 2 PID: 5825 Comm: tipc-config Tainted: G           O 3.11.0-rc3-wwd-    default #4
[  327.696018] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[  327.696018]  00000000ffffffff ffff880037fa77a8 ffffffff814d03dd 0000000000000000
[  327.696018]  ffff880037fa7808 ffff880037fa77e8 ffffffff810b1c4f 0000000037fa77e8
[  327.696018]  ffff880037fa7808 ffff880037e4db40 0000000000000000 ffff880037e4e318
[  327.696018] Call Trace:
[  327.696018]  [<ffffffff814d03dd>] dump_stack+0x4d/0xa0
[  327.696018]  [<ffffffff810b1c4f>] print_circular_bug+0x10f/0x120
[  327.696018]  [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
[  327.696018]  [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]  [<ffffffff81087a28>] ? sched_clock_cpu+0xd8/0x110
[  327.696018]  [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]  [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
[  327.696018]  [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
[  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
[  327.696018]  [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
[  327.696018]  [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
[  327.696018]  [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
[  327.696018]  [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
[  327.696018]  [<ffffffff81218783>] ? security_capable+0x13/0x20
[  327.696018]  [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
[  327.696018]  [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
[  327.696018]  [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
[  327.696018]  [<ffffffff8143ecc0>] ? genl_lock+0x20/0x20
[  327.696018]  [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
[  327.696018]  [<ffffffff8143e608>] ? genl_rcv+0x18/0x40
[  327.696018]  [<ffffffff8143e617>] genl_rcv+0x27/0x40
[  327.696018]  [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
[  327.696018]  [<ffffffff81289d7c>] ? memcpy_fromiovec+0x6c/0x90
[  327.696018]  [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
[  327.696018]  [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
[  327.696018]  [<ffffffff813f7957>] sock_aio_write+0x107/0x120
[  327.696018]  [<ffffffff813fe29c>] ? release_sock+0x8c/0xa0
[  327.696018]  [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
[  327.696018]  [<ffffffff8117fa24>] ? rw_verify_area+0x54/0x100
[  327.696018]  [<ffffffff8117fc56>] vfs_write+0x186/0x190
[  327.696018]  [<ffffffff811803e0>] SyS_write+0x60/0xb0
[  327.696018]  [<ffffffff814de852>] system_call_fastpath+0x16/0x1b

-----------------------------------------------------------------------

The problem is that the tipc_link_delete() will cancel the timer disc_timeout() when
the b_ptr->lock is hold, but the disc_timeout() still call b_ptr->lock to finish the
work, so the dead lock occurs.

We should unlock the b_ptr->lock when del the disc_timeout().

Remove link_timeout() still met the same problem, the patch:

http://article.gmane.org/gmane.network.tipc.general/4380

fix the problem, so no need to send patch for fix link_timeout() deadlock warming.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-11 21:58:41 -07:00
Ying Xue c756891a4e tipc: fix oops when creating server socket fails
When creation of TIPC internal server socket fails,
we get an oops with the following dump:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
IP: [<ffffffffa0011f49>] tipc_close_conn+0x59/0xb0 [tipc]
PGD 13719067 PUD 12008067 PMD 0
Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
Modules linked in: tipc(+)
CPU: 4 PID: 4340 Comm: insmod Not tainted 3.10.0+ #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
task: ffff880014360000 ti: ffff88001374c000 task.ti: ffff88001374c000
RIP: 0010:[<ffffffffa0011f49>]  [<ffffffffa0011f49>] tipc_close_conn+0x59/0xb0 [tipc]
RSP: 0018:ffff88001374dc98  EFLAGS: 00010292
RAX: 0000000000000000 RBX: ffff880012ac09d8 RCX: 0000000000000000
RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffff880014360000
RBP: ffff88001374dcb8 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffffa0016fa0
R13: ffffffffa0017010 R14: ffffffffa0017010 R15: ffff880012ac09d8
FS:  0000000000000000(0000) GS:ffff880016600000(0063) knlGS:00000000f76668d0
CS:  0010 DS: 002b ES: 002b CR0: 000000008005003b
CR2: 0000000000000020 CR3: 0000000012227000 CR4: 00000000000006e0
Stack:
ffff88001374dcb8 ffffffffa0016fa0 0000000000000000 0000000000000001
ffff88001374dcf8 ffffffffa0012922 ffff88001374dce8 00000000ffffffea
ffffffffa0017100 0000000000000000 ffff8800134241a8 ffffffffa0017150
Call Trace:
[<ffffffffa0012922>] tipc_server_stop+0xa2/0x1b0 [tipc]
[<ffffffffa0009995>] tipc_subscr_stop+0x15/0x20 [tipc]
[<ffffffffa00130f5>] tipc_core_stop+0x1d/0x33 [tipc]
[<ffffffffa001f0d4>] tipc_init+0xd4/0xf8 [tipc]
[<ffffffffa001f000>] ? 0xffffffffa001efff
[<ffffffff8100023f>] do_one_initcall+0x3f/0x150
[<ffffffff81082f4d>] ? __blocking_notifier_call_chain+0x7d/0xd0
[<ffffffff810cc58a>] load_module+0x11aa/0x19c0
[<ffffffff810c8d60>] ? show_initstate+0x50/0x50
[<ffffffff8190311c>] ? retint_restore_args+0xe/0xe
[<ffffffff810cce79>] SyS_init_module+0xd9/0x110
[<ffffffff8190dc65>] sysenter_dispatch+0x7/0x1f
Code: 6c 24 70 4c 89 ef e8 b7 04 8f e1 8b 73 04 4c 89 e7 e8 7c 9e 32 e1 41 83 ac 24
b8 00 00 00 01 4c 89 ef e8 eb 0a 8f e1 48 8b 43 08 <4c> 8b 68 20 4d 8d a5 48 03 00
00 4c 89 e7 e8 04 05 8f e1 4c 89
RIP  [<ffffffffa0011f49>] tipc_close_conn+0x59/0xb0 [tipc]
RSP <ffff88001374dc98>
CR2: 0000000000000020
---[ end trace b02321f40e4269a3 ]---

We have the following call chain:

tipc_core_start()
    ret = tipc_subscr_start()
        ret = tipc_server_start(){
                  server->enabled = 1;
                  ret = tipc_open_listening_sock()
              }

I.e., the server->enabled flag is unconditionally set to 1, whatever
the return value of tipc_open_listening_sock().

This causes a crash when tipc_core_start() tries to clean up
resources after a failed initialization:

    if (ret == failed)
        tipc_subscr_stop()
            tipc_server_stop(){
                if (server->enabled)
                    tipc_close_conn(){
                        NULL reference of con->sock-sk
                        OOPS!
                }
            }

To avoid this, tipc_server_start() should only set server->enabled
to 1 in case of a succesful socket creation. In case of failure, it
should release all allocated resources before returning.

Problem introduced in commit c5fa7b3cf3
("tipc: introduce new TIPC server infrastructure") in v3.11-rc1.
Note that it won't be seen often; it takes a module load under memory
constrained conditions in order to trigger the failure condition.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-01 15:54:33 -07:00
Andy Shevchenko d77e41e127 net/tipc: use %*phC to dump small buffers in hex form
Instead of passing each byte by stack let's use nice specifier for that.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-11 17:03:36 -07:00
Ying Xue 2537af9dca tipc: remove dev_base_lock use from enable_bearer
Convert enable_bearer() to RCU locking with dev_get_by_name().

Based on a similar changeset in commit 840a185d ["aoe: remove
dev_base_lock use from aoecmd_cfg_pkts()"] -- quoting that:

  "dev_base_lock is the legacy way to lock the device list,
   and is planned to disappear. (writers hold RTNL, readers
   hold RCU lock)"

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Ying Xue 126c052464 tipc: fix wrong return value for link_send_sections_long routine
When skb buffer cannot be allocated in link_send_sections_long(),
-ENOMEM error code instead of -EFAULT should be returned to its
caller.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Ying Xue 7410f967ba tipc: make tipc_link_send_sections_fast exit earlier
Once message build request function returns invalid code, the
process of sending message cannot continue. So in case of message
build failure, tipc_link_send_sections_fast() should return
immediately.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Ying Xue 796c75d0d3 tipc: enhance priority of link protocol packet
pfifo_fast is set as default traffic class queueing discipline. This
queue has three so called "bands". Within each band, FIFO rules apply.
However, as long as there are packets waiting in band 0, band 1 won't
be processed.

Now all kind of TIPC type packet priorities are never set, that is,
their priorities are 0, so they are mapped to band 1 of pfifo_fast
qdisc. But, especially during link congestion, if link protocol packet
can be sent out as earlier as possible than other type of packets so
that protocol packet can arrive at peer endpoint in time, the peer
will timely reset its link timeout timer to keep the link alive.
So enhancing the priority of link protocol packets can meet the
specific demand to avoid unnecessary link reset due to a transient
link congestion.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Paul Gortmaker ae8509c420 tipc: cosmetic realignment of function arguments
No runtime code changes here.  Just a realign of the function
arguments to start where the 1st one was, and fit as many args
as can be put in an 80 char line.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Ying Xue c0fee8aca7 tipc: save sock structure pointer instead of void pointer to tipc_port
Directly save sock structure pointer instead of void pointer to avoid
unnecessary cast conversions.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Ying Xue 28e5297281 tipc: convert config_lock from spinlock to mutex
As the configuration server is now running under process context,
it's unnecessary for us to have a spinlock serializing the TIPC
configuration process. Instead, we replace it with a mutex lock,
which gives us more freedom. For instance, we can now call
pre-emptable functions within the protected area.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Ying Xue 3c5db8e4ec tipc: rename tipc_createport_raw to tipc_createport
After the removal of the native API, there is now only one way to
to create a TIPC port instance -- the function tipc_createport_raw().
We make it more readable by renaming it to tipc_createport().

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Ying Xue f1733d7580 tipc: remove user_port instance from tipc_port structure
After the native API has been completely removed, the 'user_port'
field in struct tipc_port becomes unused, and can be removed.
As a consequence, the "usrmem" argument in tipc_msg_build() is no
longer needed, and so we remove that one too.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Ying Xue 198d73b82b tipc: delete code orphaned by new server infrastructure
Having completed the conversion of the topology server and
configuration server to use the new server infrastructure,
the following functions become unused, and can be deleted:

   - tipc_createport()
   - port_wakeup_sh()
   - port_dispatcher()
   - port_dispatcher_sigh()
   - tipc_send_buf_fast()
   - tipc_send_buf2port

Additionally, the following variables become orphaned,
and can be deleted:

   - tipc_msg_err_event
   - tipc_named_msg_err_event
   - tipc_conn_shutdown_event
   - tipc_msg_event
   - tipc_named_msg_event
   - tipc_conn_msg_event
   - tipc_continue_event
   - msg_queue_head
   - msg_queue_tail
   - queue_lock

Deletion is done here in a separate commit in order to allow
the actual conversion changes to be more easily viewed.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Ying Xue 7d0ab17b74 tipc: convert configuration server to use new server facility
As the new socket-based TIPC server infrastructure has been
introduced, we can now convert the configuration server to use
it.  Then we can take future steps to simplify the configuration
server locking policy.

Some minor reordering of initialization is done, due to the
dependency on having tipc_socket_init completed.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Ying Xue 13a2e89873 tipc: convert topology server to use new server facility
As the new TIPC server infrastructure has been introduced, we can
now convert the TIPC topology server to it.  We get two benefits
from doing this:

1) It simplifies the topology server locking policy.  In the
original locking policy, we placed one spin lock pointer in the
tipc_subscriber structure to reuse the lock of the subscriber's
server port, controlling access to members of tipc_subscriber
instance.  That is, we only used one lock to ensure both
tipc_port and tipc_subscriber members were safely accessed.

Now we introduce another spin lock for tipc_subscriber structure
only protecting themselves, to get a finer granularity locking
policy.  Moreover, the change will allow us to make the topology
server code more readable and maintainable.

2) It fixes a bug where sent subscription events may be lost when
the topology port is congested.  Using the new service, the
topology server now queues sent events into an outgoing buffer,
and then wakes up a sender process which has been blocked in
workqueue context.  The process will keep picking events from the
buffer and send them to their respective subscribers, using the
kernel socket interface, until the buffer is empty. Even if the
socket is congested during transmission there is no risk that
events may be dropped, since the sender process may block when
needed.

Some minor reordering of initialization is done, since we now
have a scenario where the topology server must be started after
socket initialization has taken place, as the former depends
on the latter.  And overall, we see a simplification of the
TIPC subscriber code in making this changeover.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Ying Xue c5fa7b3cf3 tipc: introduce new TIPC server infrastructure
TIPC has two internal servers, one providing a subscription
service for topology events, and another providing the
configuration interface. These servers have previously been running
in BH context, accessing the TIPC-port (aka native) API directly.
Apart from these servers, even the TIPC socket implementation is
partially built on this API.

As this API may simultaneously be called via different paths and in
different contexts, a complex and costly lock policiy is required
in order to protect TIPC internal resources.

To eliminate the need for this complex lock policiy, we introduce
a new, generic service API that uses kernel sockets for message
passing instead of the native API. Once the toplogy and configuration
servers are converted to use this new service, all code pertaining
to the native API can be removed. This entails a significant
reduction in code amount and complexity, and opens up for a complete
rework of the locking policy in TIPC.

The new service also solves another problem:

As the current topology server works in BH context, it cannot easily
be blocked when sending of events fails due to congestion. In such
cases events may have to be silently dropped, something that is
unacceptable. Therefore, the new service keeps a dedicated outbound
queue receiving messages from BH context. Once messages are
inserted into this queue, we will immediately schedule a work from a
special workqueue. This way, messages/events from the topology server
are in reality sent in process context, and the server can block
if necessary.

Analogously, there is a new workqueue for receiving messages. Once a
notification about an arriving message is received in BH context, we
schedule a work from the receive workqueue to do the job of
receiving the message in process context.

As both sending and receive messages are now finished in processes,
subscribed events cannot be dropped any more.

As of this commit, this new server infrastructure is built, but
not actually yet called by the existing TIPC code, but since the
conversion changes required in order to use it are significant,
the addition is kept here as a separate commit.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Erik Hugne 5d21cb70db tipc: allow implicit connect for stream sockets
TIPC's implied connect feature, aka piggyback connect, allows
applications to save one syscall and all SYN/SYN-ACK signalling
overhead when setting up a connection.  Until now, this has only
been supported for SEQPACKET sockets.  Here, we make it possible
to use this feature even with stream sockets.

At the connecting side, the connection is completed when the
first data message arrives from the accepting peer.  This means
that we must allow the connecting user to call blocking recv()
before the socket has reached state SS_CONNECTED.  So we must must
relax the state machine check at recv_stream(), and allow the
recv() call even if socket is in state SS_CONNECTING.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Ying Xue cc79dd1ba9 tipc: change socket buffer overflow control to respect sk_rcvbuf
As per feedback from the netdev community, we change the buffer
overflow protection algorithm in receiving sockets so that it
always respects the nominal upper limit set in sk_rcvbuf.

Instead of scaling up from a small sk_rcvbuf value, which leads to
violation of the configured sk_rcvbuf limit, we now calculate the
weighted per-message limit by scaling down from a much bigger value,
still in the same field, according to the importance priority of the
received message.

To allow for administrative tunability of the socket receive buffer
size, we create a tipc_rmem sysctl variable to allow the user to
configure an even bigger value via sysctl command.  It is a size of
three (min/default/max) to be consistent with things like tcp_rmem.

By default, the value initialized in tipc_rmem[1] is equal to the
receive socket size needed by a TIPC_CRITICAL_IMPORTANCE message.
This value is also set as the default value of sk_rcvbuf.

Originally-by: Jon Maloy <jon.maloy@ericsson.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
[Ying: added sysctl variation to Jon's original patch]
Signed-off-by: Ying Xue <ying.xue@windriver.com>
[PG: don't compile sysctl.c if not config'd; add Documentation]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Jiri Pirko 351638e7de net: pass info struct via netdevice notifier
So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>

v2->v3: fix typo on simeth
	shortened dev_getter
	shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-28 13:11:01 -07:00
Dan Carpenter 6bf15191f6 tipc: potential divide by zero in tipc_link_recv_fragment()
The worry here is that fragm_sz could be zero since it comes from
skb->data.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-06 16:16:52 -04:00
Dan Carpenter cb4b102f0a tipc: add a bounds check in link_recv_changeover_msg()
The bearer_id here comes from skb->data and it can be a number from 0 to
7.  The problem is that the ->links[] array has only 2 elements so I
have added a range check.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-06 16:16:52 -04:00
Gerlando Falauto 488fc9af82 tipc: pskb_copy() buffers when sending on more than one bearer
When sending packets, TIPC bearers use skb_clone() before writing their
hardware header. This will however NOT copy the data buffer.
So when the same packet is sent over multiple bearers (to reach multiple
nodes), the same socket buffer data will be treated by multiple
tipc_media drivers which will write their own hardware header through
dev_hard_header().
Most of the time this is not a problem, because by the time the
packet is processed by the second media, it has already been sent over
the first one. However, when the first transmission is delayed (e.g.
because of insufficient bandwidth or through a shaper), the next bearer
will overwrite the hardware header, resulting in the packet being sent:
a) with the wrong source address, when bearers of the same type,
e.g. ethernet, are involved
b) with a completely corrupt header, or even dropped, when bearers of
different types are involved.

So when the same socket buffer is to be sent multiple times, send a
pskb_copy() instead (from the second instance on), and release it
afterwards (the bearer will skb_clone() it anyway).

Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-03 16:08:58 -04:00
Gerlando Falauto 77861d9c00 tipc: tipc_bcbearer_send(): simplify bearer selection
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-03 16:08:58 -04:00
Gerlando Falauto e616071094 tipc: cosmetic: clean up comments and break a long line
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-03 16:08:58 -04:00
Patrick McHardy a29a194a15 tipc: add InfiniBand media type
Add InfiniBand media type based on the ethernet media type.

The only real difference is that in case of InfiniBand, we need the entire
20 bytes of space reserved for media addresses, so the TIPC media type ID is
not explicitly stored in the packet payload.

Sample output of tipc-config:

# tipc-config -v -addr -netid -nt=all -p -m -b -n -ls

node address: <10.1.4>
current network id: 4711
Type       Lower      Upper      Port Identity              Publication Scope
0          167776257  167776257  <10.1.1:1855512577>        1855512578  cluster
           167776260  167776260  <10.1.4:1216454657>        1216454658  zone
1          1          1          <10.1.4:1216479235>        1216479236  node
Ports:
1216479235: bound to {1,1}
1216454657: bound to {0,167776260}
Media:
eth
ib
Bearers:
ib:ib0
Nodes known:
<10.1.1>: up
Link <broadcast-link>
  Window:20 packets
  RX packets:0 fragments:0/0 bundles:0/0
  TX packets:0 fragments:0/0 bundles:0/0
  RX naks:0 defs:0 dups:0
  TX naks:0 acks:0 dups:0
  Congestion bearer:0 link:0  Send queue max:0 avg:0

Link <10.1.4:ib0-10.1.1:ib0>
  ACTIVE  MTU:2044  Priority:10  Tolerance:1500 ms  Window:50 packets
  RX packets:80 fragments:0/0 bundles:0/0
  TX packets:40 fragments:0/0 bundles:0/0
  TX profile sample:22 packets  average:54 octets
  0-64:100% -256:0% -1024:0% -4096:0% -16384:0% -32768:0% -66000:0%
  RX states:410 probes:213 naks:0 defs:0 dups:0
  TX states:410 probes:197 naks:0 acks:0 dups:0
  Congestion bearer:0 link:0  Send queue max:1 avg:0

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17 14:18:33 -04:00
Patrick McHardy 76f5c6f359 tipc: set skb->protocol in eth_media packet transmission
The skb->protocol field is used by packet classifiers and for AF_PACKET
cooked format, TIPC needs to set it properly.

Fixes packet classification and ethertype of 0x0000 in cooked captures:

Out 20:c9:d0:43:12:d9 ethertype Unknown (0x0000), length 56:
	0x0000:  5b50 0028 0000 30d4 0100 1000 0100 1001  [P.(..0.........
	0x0010:  0000 03e8 0000 0001 20c9 d043 12d9 0000  ...........C....
	0x0020:  0000 0000 0000 0000                      ........

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17 14:18:33 -04:00
Patrick McHardy 8aeb89f214 tipc: move bcast_addr from struct tipc_media to struct tipc_bearer
Some network protocols, like InfiniBand, don't have a fixed broadcast
address but one that depends on the configuration. Move the bcast_addr
to struct tipc_bearer and initialize it with the broadcast address of
the network device when the bearer is enabled.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17 14:18:33 -04:00
Patrick McHardy ccc4ba2ea2 tipc: remove unused str2addr media callback
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17 14:18:33 -04:00
David S. Miller d978a6361a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/nfc/microread/mei.c
	net/netfilter/nfnetlink_queue_core.c

Pull in 'net' to get Eric Biederman's AF_UNIX fix, upon which
some cleanups are going to go on-top.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-07 18:37:01 -04:00
Mathias Krause 60085c3d00 tipc: fix info leaks via msg_name in recv_msg/recv_stream
The code in set_orig_addr() does not initialize all of the members of
struct sockaddr_tipc when filling the sockaddr info -- namely the union
is only partly filled. This will make recv_msg() and recv_stream() --
the only users of this function -- leak kernel stack memory as the
msg_name member is a local variable in net/socket.c.

Additionally to that both recv_msg() and recv_stream() fail to update
the msg_namelen member to 0 while otherwise returning with 0, i.e.
"success". This is the case for, e.g., non-blocking sockets. This will
lead to a 128 byte kernel stack leak in net/socket.c.

Fix the first issue by initializing the memory of the union with
memset(0). Fix the second one by setting msg_namelen to 0 early as it
will be updated later if we're going to fill the msg_name member.

Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-07 16:28:02 -04:00
Hong zhi guo 573ce260b3 net-next: replace obsolete NLMSG_* with type safe nlmsg_*
Signed-off-by: Hong Zhiguo <honkiko@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-28 14:25:25 -04:00
Sasha Levin b67bfe0d42 hlist: drop the node parameter from iterators
I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:24 -08:00
Linus Torvalds 06991c28f3 Driver core patches for 3.9-rc1
Here is the big driver core merge for 3.9-rc1
 
 There are two major series here, both of which touch lots of drivers all
 over the kernel, and will cause you some merge conflicts:
   - add a new function called devm_ioremap_resource() to properly be
     able to check return values.
   - remove CONFIG_EXPERIMENTAL
 
 If you need me to provide a merged tree to handle these resolutions,
 please let me know.
 
 Other than those patches, there's not much here, some minor fixes and
 updates.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 Version: GnuPG v2.0.19 (GNU/Linux)
 
 iEYEABECAAYFAlEmV0cACgkQMUfUDdst+yncCQCfbmnQZju7kzWXk6PjdFuKspT9
 weAAoMCzcAtEzzc4LXuUxxG/sXBVBCjW
 =yWAQ
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core patches from Greg Kroah-Hartman:
 "Here is the big driver core merge for 3.9-rc1

  There are two major series here, both of which touch lots of drivers
  all over the kernel, and will cause you some merge conflicts:

   - add a new function called devm_ioremap_resource() to properly be
     able to check return values.

   - remove CONFIG_EXPERIMENTAL

  Other than those patches, there's not much here, some minor fixes and
  updates"

Fix up trivial conflicts

* tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (221 commits)
  base: memory: fix soft/hard_offline_page permissions
  drivercore: Fix ordering between deferred_probe and exiting initcalls
  backlight: fix class_find_device() arguments
  TTY: mark tty_get_device call with the proper const values
  driver-core: constify data for class_find_device()
  firmware: Ignore abort check when no user-helper is used
  firmware: Reduce ifdef CONFIG_FW_LOADER_USER_HELPER
  firmware: Make user-mode helper optional
  firmware: Refactoring for splitting user-mode helper code
  Driver core: treat unregistered bus_types as having no devices
  watchdog: Convert to devm_ioremap_resource()
  thermal: Convert to devm_ioremap_resource()
  spi: Convert to devm_ioremap_resource()
  power: Convert to devm_ioremap_resource()
  mtd: Convert to devm_ioremap_resource()
  mmc: Convert to devm_ioremap_resource()
  mfd: Convert to devm_ioremap_resource()
  media: Convert to devm_ioremap_resource()
  iommu: Convert to devm_ioremap_resource()
  drm: Convert to devm_ioremap_resource()
  ...
2013-02-21 12:05:51 -08:00
David S. Miller 6338a53a2b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net into net
Pull in 'net' to take in the bug fixes that didn't make it into
3.8-final.

Also, deal with the semantic conflict of the change made to
net/ipv6/xfrm6_policy.c   A missing rt6->n neighbour release
was added to 'net', but in 'net-next' we no longer cache the
neighbour entries in the ipv6 routes so that change is not
appropriate there.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-18 23:34:21 -05:00
Ying Xue 97f8b87e91 tipc: remove redundant checking for the number of iovecs in a send request
As the number of iovecs in a send request is already limited within
UIO_MAXIOV(i.e. 1024) in __sys_sendmsg(), it's unnecessary to check it
again in TIPC stack.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-02-15 17:03:32 -05:00
Ying Xue aba79f332f tipc: byte-based overload control on socket receive queue
Change overload control to be purely byte-based, using
sk->sk_rmem_alloc as byte counter, and compare it to a calculated
upper limit for the socket receive queue.

For all connection messages, irrespective of message importance,
the overload limit is set to a constant value (i.e, 67MB). This
limit should normally never be reached because of the lower
limit used by the flow control algorithm, and is there only
as a last resort in case a faulty peer doesn't respect the send
window limit.

For datagram messages, message importance is taken into account
when calculating the overload limit. The calculation is based
on sk->sk_rcvbuf, and is hence configurable via the socket option
SO_RCVBUF.

Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-02-15 17:01:58 -05:00
Ying Xue 57467e5629 tipc: eliminate duplicated discard_rx_queue routine
The tipc function discard_rx_queue() is just a duplicated
implementation of __skb_queue_purge().  Remove the former
and directly invoke __skb_queue_purge().

In doing so, the underscores convey to the code reader, more
information about the current locking state that is assumed.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-02-15 16:10:13 -05:00
Erik Hugne c5c73dca59 tipc: fix missing spinlock init in broadcast code
After commit 3c294cb3 "tipc: remove the bearer congestion mechanism",
we try to grab the broadcast bearer lock when sending multicast
messages over the broadcast link. This will cause an oops because
the lock is never initialized. This is an old bug, but the lock
was never actually used before commit 3c294cb3, so that why it was
not visible until now.  The oops will look something like:

	BUG: spinlock bad magic on CPU#2, daemon/147
	lock: bcast_bearer+0x48/0xffffffffffffd19a [tipc],
	.magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
	Pid: 147, comm: daemon Not tainted 3.8.0-rc3+ #206
	Call Trace:
	spin_dump+0x8a/0x8f
	spin_bug+0x21/0x26
	do_raw_spin_lock+0x114/0x150
	_raw_spin_lock_bh+0x19/0x20
	tipc_bearer_blocked+0x1f/0x40 [tipc]
	tipc_link_send_buf+0x82/0x280 [tipc]
	? __alloc_skb+0x9f/0x2b0
	tipc_bclink_send_msg+0x77/0xa0 [tipc]
	tipc_multicast+0x11b/0x1b0 [tipc]
	send_msg+0x225/0x530 [tipc]
	sock_sendmsg+0xca/0xe0

The above can be triggered by running the multicast demo program.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-02-15 15:40:56 -05:00
Kees Cook f887cc48c6 net/tipc: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Jon Maloy <jon.maloy@ericsson.com>
CC: Allan Stephens <allan.stephens@windriver.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David S. Miller <davem@davemloft.net>
2013-01-11 11:40:02 -08:00
Paul Gortmaker 0fef8f205f tipc: refactor accept() code for improved readability
In TIPC's accept() routine, there is a large block of code relating
to initialization of a new socket, all within an if condition checking
if the allocation succeeded.

Here, we simply flip the check of the if, so that the main execution
path stays at the same indentation level, which improves readability.
If the allocation fails, we jump to an already existing exit label.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 17:23:24 -05:00
Ying Xue 258f8667a2 tipc: add lock nesting notation to quiet lockdep warning
TIPC accept() call grabs the socket lock on a newly allocated
socket while holding the socket lock on an old socket. But lockdep
worries that this might be a recursive lock attempt:

  [ INFO: possible recursive locking detected ]
  ---------------------------------------------
  kworker/u:0/6 is trying to acquire lock:
  (sk_lock-AF_TIPC){+.+.+.}, at: [<c8c1226c>] accept+0x15c/0x310 [tipc]

  but task is already holding lock:
  (sk_lock-AF_TIPC){+.+.+.}, at: [<c8c12138>] accept+0x28/0x310 [tipc]

  other info that might help us debug this:
  Possible unsafe locking scenario:

          CPU0
          ----
          lock(sk_lock-AF_TIPC);
          lock(sk_lock-AF_TIPC);

          *** DEADLOCK ***

  May be due to missing lock nesting notation
  [...]

Tell lockdep that this locking is safe by using lock_sock_nested().
This is similar to what was done in commit 5131a184a3 for
SCTP code ("SCTP: lock_sock_nested in sctp_sock_migrate").

Also note that this is isn't something that is seen normally,
as it was uncovered with some experimental work-in-progress
code not yet ready for mainline.  So no need for stable
backports or similar of this commit.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 17:23:23 -05:00
Ying Xue cbab368790 tipc: eliminate connection setup for implied connect in recv_msg()
As connection setup is now completed asynchronously in BH context,
in the function filter_connect(), the corresponding code in recv_msg()
becomes redundant.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 17:23:22 -05:00
Ying Xue 584d24b396 tipc: introduce non-blocking socket connect
TIPC has so far only supported blocking connect(), meaning that a call
to connect() doesn't return until either the connection is fully
established, or an error occurs. This has proved insufficient for many
users, so we now introduce non-blocking connect(), analogous to how
this is done in TCP and other protocols.

With this feature, if a connection cannot be established instantly,
connect() will return the error code "-EINPROGRESS".
If the user later calls connect() again, he will either have the
return code "-EALREADY" or "-EISCONN", depending on whether the
connection has been established or not.

The user must have explicitly set the socket to be non-blocking
(SOCK_NONBLOCK or O_NONBLOCK, depending on method used), so unless
for some reason they had set this already (the socket would anyway
remain blocking in current TIPC) this change should be completely
backwards compatible.

It is also now possible to call select() or poll() to wait for the
completion of a connection.

An effect of the above is that the actual completion of a connection
may now be performed asynchronously, independent of the calls from
user space. Therefore, we now execute this code in BH context, in
the function filter_rcv(), which is executed upon reception of
messages in the socket.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
[PG: minor refactoring for improved connect/disconnect function names]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 17:23:21 -05:00
Ying Xue 7e6c131e15 tipc: consolidate connection-oriented message reception in one function
Handling of connection-related message reception is currently scattered
around at different places in the code. This makes it harder to verify
that things are handled correctly in all possible scenarios.
So we consolidate the existing processing of connection-oriented
message reception in a single routine.  In the process, we convert the
chain of if/else into a switch/case for improved readability.

A cast on the socket_state in the switch is needed to avoid compile
warnings on 32 bit, like "net/tipc/socket.c:1252:2: warning: case value
‘4294967295’ not in enumerated type".  This happens because existing
tipc code pseudo extends the default linux socket state values with:

	#define SS_LISTENING    -1      /* socket is listening */
	#define SS_READY        -2      /* socket is connectionless */

It may make sense to add these as _positive_ values to the existing
socket state enum list someday, vs. these already existing defines.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
[PG: add cast to fix warning; remove returns from middle of switch]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 17:23:20 -05:00
Paul Gortmaker bc879117d4 tipc: standardize across connect/disconnect function naming
Currently we have tipc_disconnect and tipc_disconnect_port.  It is
not clear from the names alone, what they do or how they differ.
It turns out that tipc_disconnect just deals with the port locking
and then calls tipc_disconnect_port which does all the work.

If we rename as follows: tipc_disconnect_port --> __tipc_disconnect
then we will be following typical linux convention, where:

   __tipc_disconnect: "raw" function that does all the work.

   tipc_disconnect: wrapper that deals with locking and then calls
		    the real core __tipc_disconnect function

With this, the difference is immediately evident, and locking
violations are more apt to be spotted by chance while working on,
or even just while reading the code.

On the connect side of things, we currently only have the single
"tipc_connect2port" function.  It does both the locking at enter/exit,
and the core of the work.  Pending changes will make it desireable to
have the connect be a two part locking wrapper + worker function,
just like the disconnect is already.

Here, we make the connect look just like the updated disconnect case,
for the above reason, and for consistency.  In the process, we also
get rid of the "2port" suffix that was on the original name, since
it adds no descriptive value.

On close examination, one might notice that the above connect
changes implicitly move the call to tipc_link_get_max_pkt() to be
within the scope of tipc_port_lock() protected region; when it was
not previously.  We don't see any issues with this, and it is in
keeping with __tipc_connect doing the work and tipc_connect just
handling the locking.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 17:23:19 -05:00
Jon Maloy e643df156a tipc: change sk_receive_queue upper limit
The sk_recv_queue upper limit for connectionless sockets has empirically
turned out to be too low. When we double the current limit we get much
fewer rejected messages and no noticable negative side-effects.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 17:23:18 -05:00
Ying Xue 9da3d47587 tipc: eliminate aggregate sk_receive_queue limit
As a complement to the per-socket sk_recv_queue limit, TIPC keeps a
global atomic counter for the sum of sk_recv_queue sizes across all
tipc sockets. When incremented, the counter is compared to an upper
threshold value, and if this is reached, the message is rejected
with error code TIPC_OVERLOAD.

This check was originally meant to protect the node against
buffer exhaustion and general CPU overload. However, all experience
indicates that the feature not only is redundant on Linux, but even
harmful. Users run into the limit very often, causing disturbances
for their applications, while removing it seems to have no negative
effects at all. We have also seen that overall performance is
boosted significantly when this bottleneck is removed.

Furthermore, we don't see any other network protocols maintaining
such a mechanism, something strengthening our conviction that this
control can be eliminated.

As a result, the atomic variable tipc_queue_size is now unused
and so it can be deleted.  There is a getsockopt call that used
to allow reading it; we retain that but just return zero for
maximum compatibility.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
[PG: phase out tipc_queue_size as pointed out by Neil Horman]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-07 14:19:52 -05:00
Erik Hugne c008413850 tipc: remove obsolete flush of stale reassembly buffer
Each link instance has a periodic job checking if there is a stale
ongoing message reassembly associated to the link. If no new
fragment has been received during the last 4*[link_tolerance] period,
it is assumed the missing fragment will never arrive. As a consequence,
the reassembly buffer is discarded, and a gap in the message sequence
occurs.

This assumption is wrong. After we abandoned our ambition to develop
packet routing for multi-cluster networks, only single-hop packet
transfer remains as an option. For those, all packets are guaranteed
to be delivered in sequence to the defragmentation layer. Any failure
to achieve sequenced delivery will eventually lead to link reset, and
the reassembly buffer will be flushed anyway.

So we just remove this periodic check, which is now obsolete.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
[PG: also delete get/inc_timer count, since they are now unused]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-12-06 17:20:19 -05:00
Paul Gortmaker 94fc9c4719 tipc: delete TIPC_ADVANCED Kconfig variable
There used to be a time when TIPC had lots of Kconfig knobs the
end user could alter, but they have all been made automatic or
obsolete, with the exception of CONFIG_TIPC_PORTS.  This
previously existing set of options was all hidden under the
TIPC_ADVANCED setting, which does not exist in any code, but
only in Kconfig scope.

Having this now, just to hide the one remaining "advanced"
option no longer makes sense.  Remove it.  Also get rid of the
ifdeffery in the TIPC code that allowed for TIPC_PORTS to be
possibly undefined.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-11-22 14:33:29 -05:00
Ying Xue 4cb7d55ab4 tipc: eliminate an unnecessary cast of node variable
As the variable:node is currently defined to u32 type, it is
unnecessary to cast its type to u32 again when using it.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-11-22 14:33:28 -05:00