linux.git/net/tipc/bcast.c, branch v3.9

tipc: fix missing spinlock init in broadcast code

2013-02-15T20:40:56+00:00

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: /-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 
Signed-off-by: Paul Gortmaker 
Signed-off-by: David S. Miller

tipc: rename supported flag to recv_permitted

2012-11-22T12:50:51+00:00

Rename the "supported" flag in bclink structure to "recv_permitted"
to better reflect what it is used for. When this flag is set for a
given node, we are permitted to receive and acknowledge broadcast
messages from that node.  Convert it to a bool at the same time,
since it is not used to store any numerical values.

Signed-off-by: Ying Xue 
Signed-off-by: Jon Maloy 
Signed-off-by: Paul Gortmaker

tipc: remove the bearer congestion mechanism

2012-11-22T01:07:25+00:00

Currently at the TIPC bearer layer there is the following congestion
mechanism:

Once sending packets has failed via that bearer, the bearer will be
flagged as being in congested state at once. During bearer congestion,
all packets arriving at link will be queued on the link's outgoing
buffer.  When we detect that the state of bearer congestion has
relaxed (e.g. some packets are received from the bearer) we will try
our best to push all packets in the link's outgoing buffer until the
buffer is empty, or until the bearer is congested again.

However, in fact the TIPC bearer never receives any feedback from the
device layer whether a send was successful or not, so it must always
assume it was successful. Therefore, the bearer congestion mechanism
as it exists currently is of no value.

But the bearer blocking state is still useful for us. For example,
when the physical media goes down/up, we need to change the state of
the links bound to the bearer.  So the code maintaing the state
information is not removed.

Signed-off-by: Ying Xue 
Signed-off-by: Paul Gortmaker

tipc: phase out most of the struct print_buf usage

2012-07-13T23:33:28+00:00

The tipc_printf is renamed to tipc_snprintf, as the new name
describes more what the function actually does.  It is also
changed to take a buffer and length parameter and return
number of characters written to the buffer.  All callers of
this function that used to pass a print_buf are updated.

Final removal of the struct print_buf itself will be done
synchronously with the pending removal of the deprecated
logging code that also was using it.

Functions that build up a response message with a list of
ports, nametable contents etc. are changed to return the number
of characters written to the output buffer. This information
was previously hidden in a field of the print_buf struct, and
the number of chars written was fetched with a call to
tipc_printbuf_validate.  This function is removed since it
is no longer referenced nor needed.

A generic max size ULTRA_STRING_MAX_LEN is defined, named
in keeping with the existing TIPC_TLV_ULTRA_STRING, and the
various definitions in port, link and nametable code that
largely duplicated this information are removed.  This means
that amount of link statistics that can be returned is now
increased from 2k to 32k.

The buffer overflow check is now done just before the reply
message is passed over netlink or TIPC to a remote node and
the message indicating a truncated buffer is changed to a less
dramatic one (less CAPS), placed at the end of the message.

Signed-off-by: Erik Hugne 
Signed-off-by: Jon Maloy 
Signed-off-by: Paul Gortmaker

tipc: use standard printk shortcut macros (pr_err etc.)

2012-07-13T23:24:44+00:00

All messages should go directly to the kernel log.  The TIPC
specific error, warning, info and debug trace macro's are
removed and all references replaced with pr_err, pr_warn,
pr_info and pr_debug.

Commonly used sub-strings are explicitly declared as a const
char to reduce .text size.

Note that this means the debug messages (changed to pr_debug),
are now enabled through dynamic debugging, instead of a TIPC
specific Kconfig option (TIPC_DEBUG).  The latter will be
phased out completely

Signed-off-by: Erik Hugne 
Signed-off-by: Jon Maloy 
[PG: use pr_fmt as suggested by Joe Perches ]
Signed-off-by: Paul Gortmaker

net: Fix (nearly-)kernel-doc comments for various functions

2012-07-11T06:13:45+00:00

Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches.

Signed-off-by: Ben Hutchings 
Signed-off-by: David S. Miller

tipc: compress out gratuitous extra carriage returns

2012-04-30T19:53:56+00:00

Some of the comment blocks are floating in limbo between two
functions, or between blocks of code.  Delete the extra line
feeds between any comment and its associated following block
of code, to be consistent with the majority of the rest of
the kernel.  Also delete trailing newlines at EOF and fix
a couple trivial typos in existing comments.

This is a 100% cosmetic change with no runtime impact.  We get
rid of over 500 lines of non-code, and being blank line deletes,
they won't even show up as noise in git blame.

Signed-off-by: Paul Gortmaker

tipc: Eliminate trivial buffer manipulation helper routines

2012-02-24T22:05:16+00:00

Gets rid of two inlined routines that simply call existing sk_buff
manipulation routines, since there is no longer any extra processing
done by the helper routines.

Note that these changes are essentially cosmetic in nature, and have
no impact on the actual operation of TIPC.

Signed-off-by: Allan Stephens 
Signed-off-by: Paul Gortmaker

tipc: Prevent loss of fragmented messages over broadcast link

2012-02-06T21:59:19+00:00

Modifies broadcast link so that an incoming fragmented message is not
lost if reassembly cannot begin because there currently is no buffer
big enough to hold the entire reassembled message. The broadcast link
now ignores the first fragment completely, which causes the sending node
to retransmit the first fragment so that reassembly can be re-attempted.

Previously, the sender would have had no reason to retransmit the 1st
fragment, so we would never have a chance to re-try the allocation.

To do this cleanly without duplicaton, a new bclink_accept_pkt()
function is introduced.

Signed-off-by: Allan Stephens 
Signed-off-by: Paul Gortmaker

tipc: Remove obsolete broadcast tag capability

2012-02-06T21:59:18+00:00

Eliminates support for the broadcast tag field, which is no longer
used by broadcast link NACK messages.

Signed-off-by: Allan Stephens 
Signed-off-by: Paul Gortmaker