- 05 Jun, 2012 34 commits
-
-
Mat Martineau authored
This enables the new receive and transmit state machines. Signed-off-by:
Mat Martineau <mathewm@codeaurora.org> Signed-off-by:
Gustavo Padovan <gustavo.padovan@collabora.co.uk>
-
Mat Martineau authored
Now that l2cap_ctrl is used to set up control fields, these macros are not needed. Signed-off-by:
-
Mat Martineau authored
The transmit window values must be configured for streaming mode, even though streaming mode does not have a window. This enables use of extended headers when the transmit window socket option is set to 64 or larger. Signed-off-by:
-
Mat Martineau authored
Let the compiler decide if inlining is appropriate. Signed-off-by:
-
Mat Martineau authored
Since l2cap_send_ack can trigger extra actions like sending iframes, don't call it. Just send an RR or RNR frame if an ack needs sending. Signed-off-by:
-
Mat Martineau authored
Different states have different actions for retransmit and monitor timeouts, so remove the logic for those actions from the timer handlers. Signed-off-by:
-
Mat Martineau authored
The ERTM specification requires the retransmit timer to be cancelled when the monitor timer is set. The retransmit timer cannot be set again while the monitor timer is pending. Signed-off-by:
-
Mat Martineau authored
struct l2cap_ctrl is now used, and the sframe is now sent directly rather than depending on a separate call. Signed-off-by:
-
Mat Martineau authored
REJ frames are sent by the remote device to request that all frames after a given sequence number be retransmitted. These are also an implicit indication that the remote device is not in a busy state and can receive new iframes. Signed-off-by:
-
Mat Martineau authored
When a remote device sends an SREJ, retransmit the frame with the corresponding sequence number (subject to special cases with poll and final flags). An SREJ is also an implicit indication the the remote device is not in a busy state. Signed-off-by:
-
Mat Martineau authored
As retransmitted packets arrive, attempt to reassemble SDUs. If all requested retransmissions have been received, acknowledge them and transition back to the RECV state. Signed-off-by:
-
Mat Martineau authored
The ERTM specification lays out three scenarios for sending SREJ frames to request retransmission of specific frames. l2cap_send_srej requests all frames up to a given txseq that are not already queued for reassembly. l2cap_send_srej_tail only requests the most recent missing frame. l2cap_send_srej_list resends SREJ frames for data that was requested for resend but never received. Signed-off-by:
-
Mat Martineau authored
This adds l2cap_ertm_resend to retransmit frames based on the sequence numbers in chan->retrans_list. If the retransmit limit is reached for any individual frame is reached, the connection is dropped. skbs that are cloned already are copied to avoid modifying shared data (this is uncommon). To retransmit all frames, l2cap_retransmit_all now builds a list of all unacked sequence numbers and then calls l2cap_ertm_resend. Signed-off-by:
-
Mat Martineau authored
This adds a top-level state machine with handlers for two receive states defined in the ERTM spec, RECV and SREJ_SENT. The reqseq value of the incoming frame is also validated at the top level and a disconnection is forced if it is invalid. The actions for the RECV and SREJ_SENT states are implemented according to the state tables in the ERTM specification. Signed-off-by:
-
Mat Martineau authored
This action now exactly matches what is defined in the ERTM specification, including clearing the remote busy flag and setting the retransmit timer rather than retransmitting frames directly. The spec does not retransmit frames as part of this action, since retransmission is only triggered by REJ, SREJ, or an RR with the final bit set. struct l2cap_ctrl is also used to set up header values. Signed-off-by:
-
Mat Martineau authored
This lets the transmit state machine handle local busy state changes, since different actions are taken in the different transmit states. Signed-off-by:
-
Mat Martineau authored
The function now encapsulates more of the logic to either immediately send an ack if the transmit window is over 75% full, or wait for the ack timer to expire if the transmit window is not full enough. It is also able to push out waiting iframes that can carry an acknowledgement. Signed-off-by:
-
Mat Martineau authored
This deletes the receive code that had handlers for each frame type at the top level, and then had logic to determine the receive state within each handler. Signed-off-by:
-
Mat Martineau authored
Streaming mode reception is fairly simple, with in-sequence frames being reassembled as they arrive. Out-of-sequence frames are dropped, and also clear any partially-assembled SDUs that may exist. The packet classifier determines if the txseq value of the incoming packet is expected, invalid (resulting in a disconnection), invalid (ignorable), duplicate, or having to do with an SREJ request that was previously sent. The rules for each classification are defined in the ERTM specification, and consolidating these rules in one place helps clarify the receive state machine. Signed-off-by:
-
Mat Martineau authored
Creates a new l2cap_data_rcv function that combines previous code from l2cap_ertm_data_rcv and l2cap_data_channel. This reduces duplicate code for streaming mode, and sets up a framework for the ERTM receive state machine. Signed-off-by:
-
Mat Martineau authored
The new implementation uses struct l2cap_ctrl to set up the sframe fields, and also reduces duplicate acks by canceling the ack timer whenever an RR or RNR frame is sent. sframe PDU generation is also split in to a separate function to separate it from the logic related to the connection state and sframe type. Signed-off-by:
-
Mat Martineau authored
The new implementation is aware of the new transmit state machine, and uses struct l2cap_ctrl to compose ERTM headers. It also has improved error handling for allocation failures, and does not send the packet until after all skb and channel data structures are updated. Signed-off-by:
-
Mat Martineau authored
This new implementation uses struct l2cap_ctrl to compose the streaming mode headers. Signed-off-by:
-
Mat Martineau authored
This implements a top-level transmit state machine with handlers for the two ERTM states defined in the specification: XMIT and WAIT_F. The state machine accepts an event and, optionally, a list of skbs to transmit. In addition to data transmission, the local busy state can be modified, acks are processed, and monitor and retransmit timeouts are handled. This mirrors the structure of the state tables in the spec. Signed-off-by:
-
Mat Martineau authored
This is to allow for ERTM state machine replacement in the patches that follow. Signed-off-by:
-
Mat Martineau authored
This fixes a regression from commit 2ead70b8 that is present in all kernels starting at v3.0. When L2CAP information was moved to struct l2cap_chan, a check was added to l2cap_chan_del to avoid certain cleanup operations when ERTM or streaming mode had not yet been initialized. The logic in the check did not take in to account that chan->conf_state is set to 0 in l2cap_chan_ready, so l2cap_chan_del failed to cancel timers and leaked memory any time the ERTM queues or lists were not empty. This change makes sure that l2cap_chan_del only returns early if ERTM initialization was not performed. Signed-off-by:
Marcel Holtmann <marcel@holtmann.org>
-
Mat Martineau authored
If the ERTM SREJ list is properly allocated but the retransmit list allocation fails, the SREJ list must be freed before returning from l2cap_ertm_init. l2cap_chan_del will not clean up the SREJ list if l2cap_ertm_init returns a failure code. Signed-off-by:
-
Gustavo Padovan authored
Follow net subsystem rules. Signed-off-by:
-
Gustavo Padovan authored
Follow net subsystem rules. Signed-off-by:
-
Gustavo Padovan authored
Follow the net subsystem rules. Signed-off-by:
-
Gustavo Padovan authored
Follow the net subsystem rules. Signed-off-by:
-
Gustavo Padovan authored
Follow the net subsystem rules. Signed-off-by:
-
Gustavo Padovan authored
Follow the net subsystem rules. Signed-off-by:
-
Gustavo Padovan authored
Follow the coding style of the net subsystem. Signed-off-by:
-
- 03 Jun, 2012 2 commits
-
-
Linus Torvalds authored
-
git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dmLinus Torvalds authored
Pull device-mapper updates from Alasdair G Kergon: "Improve multipath's retrying mechanism in some defined circumstances and provide a simple reserve/release mechanism for userspace tools to access thin provisioning metadata while the pool is in use." * tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: dm thin: provide userspace access to pool metadata dm thin: use slab mempools dm mpath: allow ioctls to trigger pg init dm mpath: delay retry of bypassed pg dm mpath: reduce size of struct multipath
-
- 02 Jun, 2012 4 commits
-
-
Joe Thornber authored
This patch implements two new messages that can be sent to the thin pool target allowing it to take a snapshot of the _metadata_. This, read-only snapshot can be accessed by userland, concurrently with the live target. Only one metadata snapshot can be held at a time. The pool's status line will give the block location for the current msnap. Since version 0.1.5 of the userland thin provisioning tools, the thin_dump program displays the msnap as follows: thin_dump -m <msnap root> <metadata dev> Available here: https://github.com/jthornber/thin-provisioning-tools Now that userland can access the metadata we can do various things that have traditionally been kernel side tasks: i) Incremental backups. By using metadata snapshots we can work out what blocks have changed over time. Combined with data snapshots we can ensure the data doesn't change while we back it up. A short proof of concept script can be found here: https://github.com/jthornber/thinp-test-suite/blob/master/incremental_backup_example.rb ii) Migration of thin devices from one pool to another. iii) Merging snapshots back into an external origin. iv) Asyncronous replication. Signed-off-by:Joe Thornber <ejt@redhat.com> Signed-off-by:
Alasdair G Kergon <agk@redhat.com>
-
Mike Snitzer authored
Use dedicated caches prefixed with a "dm_" name rather than relying on kmalloc mempools backed by generic slab caches so the memory usage of thin provisioning (and any leaks) can be accounted for independently. Signed-off-by:
Mike Snitzer <snitzer@redhat.com> Signed-off-by:
-
Mikulas Patocka authored
After the failure of a group of paths, any alternative paths that need initialising do not become available until further I/O is sent to the device. Until this has happened, ioctls return -EAGAIN. With this patch, new paths are made available in response to an ioctl too. The processing of the ioctl gets delayed until this has happened. Instead of returning an error, we submit a work item to kmultipathd (that will potentially activate the new path) and retry in ten milliseconds. Note that the patch doesn't retry an ioctl if the ioctl itself fails due to a path failure. Such retries should be handled intelligently by the code that generated the ioctl in the first place, noting that some SCSI commands should not be retried because they are not idempotent (XOR write commands). For commands that could be retried, there is a danger that if the device rejected the SCSI command, the path could be errorneously marked as failed, and the request would be retried on another path which might fail too. It can be determined if the failure happens on the device or on the SCSI controller, but there is no guarantee that all SCSI drivers set these flags correctly. Signed-off-by:
Mikulas Patocka <mpatocka@redhat.com> Signed-off-by:
-
Mike Christie authored
If I/O needs retrying and only bypassed priority groups are available, set the pg_init_delay_retry flag to wait before retrying. If, for example, the reason for the bypass is that the controller is getting reset or there is a firmware upgrade happening, retrying right away would cause a flood of log messages and retries for what could be a few seconds or even several minutes. Signed-off-by:
Mike Christie <michaelc@cs.wisc.edu> Acked-by:
-
