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2012-08-21libceph: avoid truncation due to racing bannersJim Schutt
Because the Ceph client messenger uses a non-blocking connect, it is possible for the sending of the client banner to race with the arrival of the banner sent by the peer. When ceph_sock_state_change() notices the connect has completed, it schedules work to process the socket via con_work(). During this time the peer is writing its banner, and arrival of the peer banner races with con_work(). If con_work() calls try_read() before the peer banner arrives, there is nothing for it to do, after which con_work() calls try_write() to send the client's banner. In this case Ceph's protocol negotiation can complete succesfully. The server-side messenger immediately sends its banner and addresses after accepting a connect request, *before* actually attempting to read or verify the banner from the client. As a result, it is possible for the banner from the server to arrive before con_work() calls try_read(). If that happens, try_read() will read the banner and prepare protocol negotiation info via prepare_write_connect(). prepare_write_connect() calls con_out_kvec_reset(), which discards the as-yet-unsent client banner. Next, con_work() calls try_write(), which sends the protocol negotiation info rather than the banner that the peer is expecting. The result is that the peer sees an invalid banner, and the client reports "negotiation failed". Fix this by moving con_out_kvec_reset() out of prepare_write_connect() to its callers at all locations except the one where the banner might still need to be sent. [elder@inktak.com: added note about server-side behavior] Signed-off-by: Jim Schutt <jaschut@sandia.gov> Reviewed-by: Alex Elder <elder@inktank.com>
2012-08-20libceph: delay debugfs initialization until we learn global_idSage Weil
The debugfs directory includes the cluster fsid and our unique global_id. We need to delay the initialization of the debug entry until we have learned both the fsid and our global_id from the monitor or else the second client can't create its debugfs entry and will fail (and multiple client instances aren't properly reflected in debugfs). Reported by: Yan, Zheng <zheng.z.yan@intel.com> Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-08-02libceph: fix crypto key null deref, memory leakSylvain Munaut
Avoid crashing if the crypto key payload was NULL, as when it was not correctly allocated and initialized. Also, avoid leaking it. Signed-off-by: Sylvain Munaut <tnt@246tNt.com> Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-31Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client Pull Ceph changes from Sage Weil: "Lots of stuff this time around: - lots of cleanup and refactoring in the libceph messenger code, and many hard to hit races and bugs closed as a result. - lots of cleanup and refactoring in the rbd code from Alex Elder, mostly in preparation for the layering functionality that will be coming in 3.7. - some misc rbd cleanups from Josh Durgin that are finally going upstream - support for CRUSH tunables (used by newer clusters to improve the data placement) - some cleanup in our use of d_parent that Al brought up a while back - a random collection of fixes across the tree There is another patch coming that fixes up our ->atomic_open() behavior, but I'm going to hammer on it a bit more before sending it." Fix up conflicts due to commits that were already committed earlier in drivers/block/rbd.c, net/ceph/{messenger.c, osd_client.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (132 commits) rbd: create rbd_refresh_helper() rbd: return obj version in __rbd_refresh_header() rbd: fixes in rbd_header_from_disk() rbd: always pass ops array to rbd_req_sync_op() rbd: pass null version pointer in add_snap() rbd: make rbd_create_rw_ops() return a pointer rbd: have __rbd_add_snap_dev() return a pointer libceph: recheck con state after allocating incoming message libceph: change ceph_con_in_msg_alloc convention to be less weird libceph: avoid dropping con mutex before fault libceph: verify state after retaking con lock after dispatch libceph: revoke mon_client messages on session restart libceph: fix handling of immediate socket connect failure ceph: update MAINTAINERS file libceph: be less chatty about stray replies libceph: clear all flags on con_close libceph: clean up con flags libceph: replace connection state bits with states libceph: drop unnecessary CLOSED check in socket state change callback libceph: close socket directly from ceph_con_close() ...
2012-07-30libceph: recheck con state after allocating incoming messageSage Weil
We drop the lock when calling the ->alloc_msg() con op, which means we need to (a) not clobber con->in_msg without the mutex held, and (b) we need to verify that we are still in the OPEN state when we retake it to avoid causing any mayhem. If the state does change, -EAGAIN will get us back to con_work() and loop. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: change ceph_con_in_msg_alloc convention to be less weirdSage Weil
This function's calling convention is very limiting. In particular, we can't return any error other than ENOMEM (and only implicitly), which is a problem (see next patch). Instead, return an normal 0 or error code, and make the skip a pointer output parameter. Drop the useless in_hdr argument (we have the con pointer). Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: avoid dropping con mutex before faultSage Weil
The ceph_fault() function takes the con mutex, so we should avoid dropping it before calling it. This fixes a potential race with another thread calling ceph_con_close(), or _open(), or similar (we don't reverify con->state after retaking the lock). Add annotation so that lockdep realizes we will drop the mutex before returning. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: verify state after retaking con lock after dispatchSage Weil
We drop the con mutex when delivering a message. When we retake the lock, we need to verify we are still in the OPEN state before preparing to read the next tag, or else we risk stepping on a connection that has been closed. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: revoke mon_client messages on session restartSage Weil
Revoke all mon_client messages when we shut down the old connection. This is mostly moot since we are re-using the same ceph_connection, but it is cleaner. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: fix handling of immediate socket connect failureSage Weil
If the connect() call immediately fails such that sock == NULL, we still need con_close_socket() to reset our socket state to CLOSED. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: be less chatty about stray repliesSage Weil
There are many (normal) conditions that can lead to us getting unexpected replies, include cluster topology changes, osd failures, and timeouts. There's no need to spam the console about it. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: clear all flags on con_closeSage Weil
Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: clean up con flagsSage Weil
Rename flags with CON_FLAG prefix, move the definitions into the c file, and (better) document their meaning. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: replace connection state bits with statesSage Weil
Use a simple set of 6 enumerated values for the socket states (CON_STATE_*) and use those instead of the state bits. All of the con->state checks are now under the protection of the con mutex, so this is safe. It also simplifies many of the state checks because we can check for anything other than the expected state instead of various bits for races we can think of. This appears to hold up well to stress testing both with and without socket failure injection on the server side. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: drop unnecessary CLOSED check in socket state change callbackSage Weil
If we are CLOSED, the socket is closed and we won't get these. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: close socket directly from ceph_con_close()Sage Weil
It is simpler to do this immediately, since we already hold the con mutex. It also avoids the need to deal with a not-quite-CLOSED socket in con_work. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: drop gratuitous socket close calls in con_workSage Weil
If the state is CLOSED or OPENING, we shouldn't have a socket. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: move ceph_con_send() closed check under the con mutexSage Weil
Take the con mutex before checking whether the connection is closed to avoid racing with someone else closing it. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: move msgr clear_standby under con mutex protectionSage Weil
Avoid dropping and retaking con->mutex in the ceph_con_send() case by leaving locking up to the caller. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: fix fault locking; close socket on lossy faultSage Weil
If we fault on a lossy connection, we should still close the socket immediately, and do so under the con mutex. We should also take the con mutex before printing out the state bits in the debug output. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: trivial fix for the incorrect debug outputJiaju Zhang
This is a trivial fix for the debug output, as it is inconsistent with the function name so may confuse people when debugging. [elder@inktank.com: switched to use __func__] Signed-off-by: Jiaju Zhang <jjzhang@suse.de> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: reset connection retry on successfully negotiationSage Weil
We exponentially back off when we encounter connection errors. If several errors accumulate, we will eventually wait ages before even trying to reconnect. Fix this by resetting the backoff counter after a successful negotiation/ connection with the remote node. Fixes ceph issue #2802. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: protect ceph_con_open() with mutexSage Weil
Take the con mutex while we are initiating a ceph open. This is necessary because the may have previously been in use and then closed, which could result in a racing workqueue running con_work(). Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-07-30libceph: (re)initialize bio_iter on start of message receiveSage Weil
Previously, we were opportunistically initializing the bio_iter if it appeared to be uninitialized in the middle of the read path. The problem is that a sequence like: - start reading message - initialize bio_iter - read half a message - messenger fault, reconnect - restart reading message - ** bio_iter now non-NULL, not reinitialized ** - read past end of bio, crash Instead, initialize the bio_iter unconditionally when we allocate/claim the message for read. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30libceph: resubmit linger ops when pg mapping changesSage Weil
The linger op registration (i.e., watch) modifies the object state. As such, the OSD will reply with success if it has already applied without doing the associated side-effects (setting up the watch session state). If we lose the ACK and resubmit, we will see success but the watch will not be correctly registered and we won't get notifies. To fix this, always resubmit the linger op with a new tid. We accomplish this by re-registering as a linger (i.e., 'registered') if we are not yet registered. Then the second loop will treat this just like a normal case of re-registering. This mirrors a similar fix on the userland ceph.git, commit 5dd68b95, and ceph bug #2796. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30libceph: fix mutex coverage for ceph_con_closeSage Weil
Hold the mutex while twiddling all of the state bits to avoid possible races. While we're here, make not of why we cannot close the socket directly. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30libceph: report socket read/write error messageSage Weil
We need to set error_msg to something useful before calling ceph_fault(); do so here for try_{read,write}(). This is more informative than libceph: osd0 192.168.106.220:6801 (null) Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30libceph: support crush tunablesSage Weil
The server side recently added support for tuning some magic crush variables. Decode these variables if they are present, or use the default values if they are not present. Corresponds to ceph.git commit 89af369c25f274fe62ef730e5e8aad0c54f1e5a5. Signed-off-by: caleb miles <caleb.miles@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30libceph: move feature bits to separate headerSage Weil
This is simply cleanup that will keep things more closely synced with the userland code. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-07-30libceph: prevent the race of incoming work during teardownGuanjun He
Add an atomic variable 'stopping' as flag in struct ceph_messenger, set this flag to 1 in function ceph_destroy_client(), and add the condition code in function ceph_data_ready() to test the flag value, if true(1), just return. Signed-off-by: Guanjun He <gjhe@suse.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: fix messenger retrySage Weil
In ancient times, the messenger could both initiate and accept connections. An artifact if that was data structures to store/process an incoming ceph_msg_connect request and send an outgoing ceph_msg_connect_reply. Sadly, the negotiation code was referencing those structures and ignoring important information (like the peer's connect_seq) from the correct ones. Among other things, this fixes tight reconnect loops where the server sends RETRY_SESSION and we (the client) retries with the same connect_seq as last time. This bug pretty easily triggered by injecting socket failures on the MDS and running some fs workload like workunits/direct_io/test_sync_io. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: initialize rb, list nodes in ceph_osd_requestSage Weil
These don't strictly need to be initialized based on how they are used, but it is good practice to do so. Reported-by: Alex Elder <elder@inktank.com> Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-30libceph: initialize msgpool message typesSage Weil
Initialize the type field for messages in a msgpool. The caller was doing this for osd ops, but not for the reply messages. Reported-by: Alex Elder <elder@inktank.com> Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking changes from David S Miller: 1) Remove the ipv4 routing cache. Now lookups go directly into the FIB trie and use prebuilt routes cached there. No more garbage collection, no more rDOS attacks on the routing cache. Instead we now get predictable and consistent performance, no matter what the pattern of traffic we service. This has been almost 2 years in the making. Special thanks to Julian Anastasov, Eric Dumazet, Steffen Klassert, and others who have helped along the way. I'm sure that with a change of this magnitude there will be some kind of fallout, but such things ought the be simple to fix at this point. Luckily I'm not European so I'll be around all of August to fix things :-) The major stages of this work here are each fronted by a forced merge commit whose commit message contains a top-level description of the motivations and implementation issues. 2) Pre-demux of established ipv4 TCP sockets, saves a route demux on input. 3) TCP SYN/ACK performance tweaks from Eric Dumazet. 4) Add namespace support for netfilter L4 conntrack helpers, from Gao Feng. 5) Add config mechanism for Energy Efficient Ethernet to ethtool, from Yuval Mintz. 6) Remove quadratic behavior from /proc/net/unix, from Eric Dumazet. 7) Support for connection tracker helpers in userspace, from Pablo Neira Ayuso. 8) Allow userspace driven TX load balancing functions in TEAM driver, from Jiri Pirko. 9) Kill off NLMSG_PUT and RTA_PUT macros, more gross stuff with embedded gotos. 10) TCP Small Queues, essentially minimize the amount of TCP data queued up in the packet scheduler layer. Whereas the existing BQL (Byte Queue Limits) limits the pkt_sched --> netdevice queuing levels, this controls the TCP --> pkt_sched queueing levels. From Eric Dumazet. 11) Reduce the number of get_page/put_page ops done on SKB fragments, from Alexander Duyck. 12) Implement protection against blind resets in TCP (RFC 5961), from Eric Dumazet. 13) Support the client side of TCP Fast Open, basically the ability to send data in the SYN exchange, from Yuchung Cheng. Basically, the sender queues up data with a sendmsg() call using MSG_FASTOPEN, then they do the connect() which emits the queued up fastopen data. 14) Avoid all the problems we get into in TCP when timers or PMTU events hit a locked socket. The TCP Small Queues changes added a tcp_release_cb() that allows us to queue work up to the release_sock() caller, and that's what we use here too. From Eric Dumazet. 15) Zero copy on TX support for TUN driver, from Michael S. Tsirkin. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1870 commits) genetlink: define lockdep_genl_is_held() when CONFIG_LOCKDEP r8169: revert "add byte queue limit support". ipv4: Change rt->rt_iif encoding. net: Make skb->skb_iif always track skb->dev ipv4: Prepare for change of rt->rt_iif encoding. ipv4: Remove all RTCF_DIRECTSRC handliing. ipv4: Really ignore ICMP address requests/replies. decnet: Don't set RTCF_DIRECTSRC. net/ipv4/ip_vti.c: Fix __rcu warnings detected by sparse. ipv4: Remove redundant assignment rds: set correct msg_namelen openvswitch: potential NULL deref in sample() tcp: dont drop MTU reduction indications bnx2x: Add new 57840 device IDs tcp: avoid oops in tcp_metrics and reset tcpm_stamp niu: Change niu_rbr_fill() to use unlikely() to check niu_rbr_add_page() return value niu: Fix to check for dma mapping errors. net: Fix references to out-of-scope variables in put_cmsg_compat() net: ethernet: davinci_emac: add pm_runtime support net: ethernet: davinci_emac: Remove unnecessary #include ...
2012-07-17libceph: fix messenger retrySage Weil
In ancient times, the messenger could both initiate and accept connections. An artifact if that was data structures to store/process an incoming ceph_msg_connect request and send an outgoing ceph_msg_connect_reply. Sadly, the negotiation code was referencing those structures and ignoring important information (like the peer's connect_seq) from the correct ones. Among other things, this fixes tight reconnect loops where the server sends RETRY_SESSION and we (the client) retries with the same connect_seq as last time. This bug pretty easily triggered by injecting socket failures on the MDS and running some fs workload like workunits/direct_io/test_sync_io. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-10net: Fix non-kernel-doc comments with kernel-doc start markerBen Hutchings
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-05libceph: allow sock transition from CONNECTING to CLOSEDSage Weil
It is possible to close a socket that is in the OPENING state. For example, it can happen if ceph_con_close() is called on the con before the TCP connection is established. con_work() will come around and shut down the socket. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: initialize mon_client con only onceSage Weil
Do not re-initialize the con on every connection attempt. When we ceph_con_close, there may still be work queued on the socket (e.g., to close it), and re-initializing will clobber the work_struct state. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: set peer name on con_open, not initSage Weil
The peer name may change on each open attempt, even when the connection is reused. Signed-off-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: add some fine ASCII artAlex Elder
Sage liked the state diagram I put in my commit description so I'm putting it in with the code. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: small changes to messenger.cAlex Elder
This patch gathers a few small changes in "net/ceph/messenger.c": out_msg_pos_next() - small logic change that mostly affects indentation write_partial_msg_pages(). - use a local variable trail_off to represent the offset into a message of the trail portion of the data (if present) - once we are in the trail portion we will always be there, so we don't always need to check against our data position - avoid computing len twice after we've reached the trail - get rid of the variable tmpcrc, which is not needed - trail_off and trail_len never change so mark them const - update some comments read_partial_message_bio() - bio_iovec_idx() will never return an error, so don't bother checking for it Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: distinguish two phases of connect sequenceAlex Elder
Currently a ceph connection enters a "CONNECTING" state when it begins the process of (re-)connecting with its peer. Once the two ends have successfully exchanged their banner and addresses, an additional NEGOTIATING bit is set in the ceph connection's state to indicate the connection information exhange has begun. The CONNECTING bit/state continues to be set during this phase. Rather than have the CONNECTING state continue while the NEGOTIATING bit is set, interpret these two phases as distinct states. In other words, when NEGOTIATING is set, clear CONNECTING. That way only one of them will be active at a time. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: separate banner and connect writesAlex Elder
There are two phases in the process of linking together the two ends of a ceph connection. The first involves exchanging a banner and IP addresses, and if that is successful a second phase exchanges some detail about each side's connection capabilities. When initiating a connection, the client side now queues to send its information for both phases of this process at the same time. This is probably a bit more efficient, but it is slightly messier from a layering perspective in the code. So rearrange things so that the client doesn't send the connection information until it has received and processed the response in the initial banner phase (in process_banner()). Move the code (in the (con->sock == NULL) case in try_write()) that prepares for writing the connection information, delaying doing that until the banner exchange has completed. Move the code that begins the transition to this second "NEGOTIATING" phase out of process_banner() and into its caller, so preparing to write the connection information and preparing to read the response are adjacent to each other. Finally, preparing to write the connection information now requires the output kvec to be reset in all cases, so move that into the prepare_write_connect() and delete it from all callers. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: define and use an explicit CONNECTED stateAlex Elder
There is no state explicitly defined when a ceph connection is fully operational. So define one. It's set when the connection sequence completes successfully, and is cleared when the connection gets closed. Be a little more careful when examining the old state when a socket disconnect event is reported. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: clear NEGOTIATING when doneAlex Elder
A connection state's NEGOTIATING bit gets set while in CONNECTING state after we have successfully exchanged a ceph banner and IP addresses with the connection's peer (the server). But that bit is not cleared again--at least not until another connection attempt is initiated. Instead, clear it as soon as the connection is fully established. Also, clear it when a socket connection gets prematurely closed in the midst of establishing a ceph connection (in case we had reached the point where it was set). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: clear CONNECTING in ceph_con_close()Alex Elder
A connection that is closed will no longer be connecting. So clear the CONNECTING state bit in ceph_con_close(). Similarly, if the socket has been closed we no longer are in connecting state (a new connect sequence will need to be initiated). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: don't touch con state in con_close_socket()Alex Elder
In con_close_socket(), a connection's SOCK_CLOSED flag gets set and then cleared while its shutdown method is called and its reference gets dropped. Previously, that flag got set only if it had not already been set, so setting it in con_close_socket() might have prevented additional processing being done on a socket being shut down. We no longer set SOCK_CLOSED in the socket event routine conditionally, so setting that bit here no longer provides whatever benefit it might have provided before. A race condition could still leave the SOCK_CLOSED bit set even after we've issued the call to con_close_socket(), so we still clear that bit after shutting the socket down. Add a comment explaining the reason for this. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: just set SOCK_CLOSED when state changesAlex Elder
When a TCP_CLOSE or TCP_CLOSE_WAIT event occurs, the SOCK_CLOSED connection flag bit is set, and if it had not been previously set queue_con() is called to ensure con_work() will get a chance to handle the changed state. con_work() atomically checks--and if set, clears--the SOCK_CLOSED bit if it was set. This means that even if the bit were set repeatedly, the related processing in con_work() only gets called once per transition of the bit from 0 to 1. What's important then is that we ensure con_work() gets called *at least* once when a socket close event occurs, not that it gets called *exactly* once. The work queue mechanism already takes care of queueing work only if it is not already queued, so there's no need for us to call queue_con() conditionally. So this patch just makes it so the SOCK_CLOSED flag gets set unconditionally in ceph_sock_state_change(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: don't change socket state on sock eventAlex Elder
Currently the socket state change event handler records an error message on a connection to distinguish a close while connecting from a close while a connection was already established. Changing connection information during handling of a socket event is not very clean, so instead move this assignment inside con_work(), where it can be done during normal connection-level processing (and under protection of the connection mutex as well). Move the handling of a socket closed event up to the top of the processing loop in con_work(); there's no point in handling backoff etc. if we have a newly-closed socket to take care of. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: SOCK_CLOSED is a flag, not a stateAlex Elder
The following commit changed it so SOCK_CLOSED bit was stored in a connection's new "flags" field rather than its "state" field. libceph: start separating connection flags from state commit 928443cd That bit is used in con_close_socket() to protect against setting an error message more than once in the socket event handler function. Unfortunately, the field being operated on in that function was not updated to be "flags" as it should have been. This fixes that error. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>