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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>
2012-07-05libceph: don't use bio_iter as a flagAlex Elder
Recently a bug was fixed in which the bio_iter field in a ceph message was not being properly re-initialized when a message got re-transmitted: commit 43643528cce60ca184fe8197efa8e8da7c89a037 Author: Yan, Zheng <zheng.z.yan@intel.com> rbd: Clear ceph_msg->bio_iter for retransmitted message We are now only initializing the bio_iter field when we are about to start to write message data (in prepare_write_message_data()), rather than every time we are attempting to write any portion of the message data (in write_partial_msg_pages()). This means we no longer need to use the msg->bio_iter field as a flag. So just don't do that any more. Trust prepare_write_message_data() to ensure msg->bio_iter is properly initialized, every time we are about to begin writing (or re-writing) a message's bio data. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: move init of bio_iterAlex Elder
If a message has a non-null bio pointer, its bio_iter field is initialized in write_partial_msg_pages() if this has not been done already. This is really a one-time setup operation for sending a message's (bio) data, so move that initialization code into prepare_write_message_data() which serves that purpose. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: move init_bio_*() functions upAlex Elder
Move init_bio_iter() and iter_bio_next() up in their source file so the'll be defined before they're needed. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: don't mark footer complete before it isAlex Elder
This is a nit, but prepare_write_message() sets the FOOTER_COMPLETE flag before the CRC for the data portion (recorded in the footer) has been completely computed. Hold off setting the complete flag until we've decided it's ready to send. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: encapsulate advancing msg pageAlex Elder
In write_partial_msg_pages(), once all the data from a page has been sent we advance to the next one. Put the code that takes care of this into its own function. While modifying write_partial_msg_pages(), make its local variable "in_trail" be Boolean, and use the local variable "msg" (which is just the connection's current out_msg pointer) consistently. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-07-05libceph: encapsulate out message data setupAlex Elder
Move the code that prepares to write the data portion of a message into its own function. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-22libceph: drop ceph_con_get/put helpers and nref memberSage Weil
These are no longer used. Every ceph_connection instance is embedded in another structure, and refcounts manipulated via the get/put ops. Signed-off-by: Sage Weil <sage@inktank.com>
2012-06-22libceph: use con get/put methodsSage Weil
The ceph_con_get/put() helpers manipulate the embedded con ref count, which isn't used now that ceph_connections are embedded in other structures. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-06-20rbd: Clear ceph_msg->bio_iter for retransmitted messageYan, Zheng
The bug can cause NULL pointer dereference in write_partial_msg_pages Signed-off-by: Zheng Yan <zheng.z.yan@intel.com> Reviewed-by: Alex Elder <elder@inktank.com> (cherry picked from commit 43643528cce60ca184fe8197efa8e8da7c89a037)
2012-06-19libceph: fix NULL dereference in reset_connection()Dan Carpenter
We dereference "con->in_msg" on the line after it was set to NULL. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-06-15Merge tag 'v3.5-rc1'Sage Weil
Linux 3.5-rc1 Conflicts: net/ceph/messenger.c
2012-06-15libceph: transition socket state prior to actual connectSage Weil
Once we call ->connect(), we are racing against the actual connection, and a subsequent transition from CONNECTING -> CONNECTED. Set the state to CONNECTING before that, under the protection of the mutex, to avoid the race. This was introduced in 928443cd9644e7cfd46f687dbeffda2d1a357ff9, with the original socket state code. Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-06-07rbd: Clear ceph_msg->bio_iter for retransmitted messageYan, Zheng
The bug can cause NULL pointer dereference in write_partial_msg_pages Signed-off-by: Zheng Yan <zheng.z.yan@intel.com> Reviewed-by: Alex Elder <elder@inktank.com>
2012-06-06libceph: make ceph_con_revoke_message() a msg opAlex Elder
ceph_con_revoke_message() is passed both a message and a ceph connection. A ceph_msg allocated for incoming messages on a connection always has a pointer to that connection, so there's no need to provide the connection when revoking such a message. Note that the existing logic does not preclude the message supplied being a null/bogus message pointer. The only user of this interface is the OSD client, and the only value an osd client passes is a request's r_reply field. That is always non-null (except briefly in an error path in ceph_osdc_alloc_request(), and that drops the only reference so the request won't ever have a reply to revoke). So we can safely assume the passed-in message is non-null, but add a BUG_ON() to make it very obvious we are imposing this restriction. Rename the function ceph_msg_revoke_incoming() to reflect that it is really an operation on an incoming message. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-06libceph: make ceph_con_revoke() a msg operationAlex Elder
ceph_con_revoke() is passed both a message and a ceph connection. Now that any message associated with a connection holds a pointer to that connection, there's no need to provide the connection when revoking a message. This has the added benefit of precluding the possibility of the providing the wrong connection pointer. If the message's connection pointer is null, it is not being tracked by any connection, so revoking it is a no-op. This is supported as a convenience for upper layers, so they can revoke a message that is not actually "in flight." Rename the function ceph_msg_revoke() to reflect that it is really an operation on a message, not a connection. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-06libceph: have messages take a connection referenceAlex Elder
There are essentially two types of ceph messages: incoming and outgoing. Outgoing messages are always allocated via ceph_msg_new(), and at the time of their allocation they are not associated with any particular connection. Incoming messages are always allocated via ceph_con_in_msg_alloc(), and they are initially associated with the connection from which incoming data will be placed into the message. When an outgoing message gets sent, it becomes associated with a connection and remains that way until the message is successfully sent. The association of an incoming message goes away at the point it is sent to an upper layer via a con->ops->dispatch method. This patch implements reference counting for all ceph messages, such that every message holds a reference (and a pointer) to a connection if and only if it is associated with that connection (as described above). For background, here is an explanation of the ceph message lifecycle, emphasizing when an association exists between a message and a connection. Outgoing Messages An outgoing message is "owned" by its allocator, from the time it is allocated in ceph_msg_new() up to the point it gets queued for sending in ceph_con_send(). Prior to that point the message's msg->con pointer is null; at the point it is queued for sending its message pointer is assigned to refer to the connection. At that time the message is inserted into a connection's out_queue list. When a message on the out_queue list has been sent to the socket layer to be put on the wire, it is transferred out of that list and into the connection's out_sent list. At that point it is still owned by the connection, and will remain so until an acknowledgement is received from the recipient that indicates the message was successfully transferred. When such an acknowledgement is received (in process_ack()), the message is removed from its list (in ceph_msg_remove()), at which point it is no longer associated with the connection. So basically, any time a message is on one of a connection's lists, it is associated with that connection. Reference counting outgoing messages can thus be done at the points a message is added to the out_queue (in ceph_con_send()) and the point it is removed from either its two lists (in ceph_msg_remove())--at which point its connection pointer becomes null. Incoming Messages When an incoming message on a connection is getting read (in read_partial_message()) and there is no message in con->in_msg, a new one is allocated using ceph_con_in_msg_alloc(). At that point the message is associated with the connection. Once that message has been completely and successfully read, it is passed to upper layer code using the connection's con->ops->dispatch method. At that point the association between the message and the connection no longer exists. Reference counting of connections for incoming messages can be done by taking a reference to the connection when the message gets allocated, and releasing that reference when it gets handed off using the dispatch method. We should never fail to get a connection reference for a message--the since the caller should already hold one. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-06libceph: have messages point to their connectionAlex Elder
When a ceph message is queued for sending it is placed on a list of pending messages (ceph_connection->out_queue). When they are actually sent over the wire, they are moved from that list to another (ceph_connection->out_sent). When acknowledgement for the message is received, it is removed from the sent messages list. During that entire time the message is "in the possession" of a single ceph connection. Keep track of that connection in the message. This will be used in the next patch (and is a helpful bit of information for debugging anyway). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-06libceph: tweak ceph_alloc_msg()Alex Elder
The function ceph_alloc_msg() is only used to allocate a message that will be assigned to a connection's in_msg pointer. Rename the function so this implied usage is more clear. In addition, make that assignment inside the function (again, since that's precisely what it's intended to be used for). This allows us to return what is now provided via the passed-in address of a "skip" variable. The return type is now Boolean to be explicit that there are only two possible outcomes. Make sure the result of an ->alloc_msg method call always sets the value of *skip properly. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-06libceph: fully initialize connection in con_init()Alex Elder
Move the initialization of a ceph connection's private pointer, operations vector pointer, and peer name information into ceph_con_init(). Rearrange the arguments so the connection pointer is first. Hide the byte-swapping of the peer entity number inside ceph_con_init() Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-01libceph: set CLOSED state bit in con_initAlex Elder
Once a connection is fully initialized, it is really in a CLOSED state, so make that explicit by setting the bit in its state field. It is possible for a connection in NEGOTIATING state to get a failure, leading to ceph_fault() and ultimately ceph_con_close(). Clear that bits if it is set in that case, to reflect that the connection truly is closed and is no longer participating in a connect sequence. Issue a warning if ceph_con_open() is called on a connection that is not in CLOSED state. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-01libceph: start tracking connection socket stateAlex Elder
Start explicitly keeping track of the state of a ceph connection's socket, separate from the state of the connection itself. Create placeholder functions to encapsulate the state transitions. -------- | NEW* | transient initial state -------- | con_sock_state_init() v ---------- | CLOSED | initialized, but no socket (and no ---------- TCP connection) ^ \ | \ con_sock_state_connecting() | ---------------------- | \ + con_sock_state_closed() \ |\ \ | \ \ | ----------- \ | | CLOSING | socket event; \ | ----------- await close \ | ^ | | | | | + con_sock_state_closing() | | / \ | | / --------------- | | / \ v | / -------------- | / -----------------| CONNECTING | socket created, TCP | | / -------------- connect initiated | | | con_sock_state_connected() | | v ------------- | CONNECTED | TCP connection established ------------- Make the socket state an atomic variable, reinforcing that it's a distinct transtion with no possible "intermediate/both" states. This is almost certainly overkill at this point, though the transitions into CONNECTED and CLOSING state do get called via socket callback (the rest of the transitions occur with the connection mutex held). We can back out the atomicity later. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil<sage@inktank.com>
2012-06-01libceph: start separating connection flags from stateAlex Elder
A ceph_connection holds a mixture of connection state (as in "state machine" state) and connection flags in a single "state" field. To make the distinction more clear, define a new "flags" field and use it rather than the "state" field to hold Boolean flag values. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil<sage@inktank.com>
2012-06-01libceph: embed ceph messenger structure in ceph_clientAlex Elder
A ceph client has a pointer to a ceph messenger structure in it. There is always exactly one ceph messenger for a ceph client, so there is no need to allocate it separate from the ceph client structure. Switch the ceph_client structure to embed its ceph_messenger structure. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-01libceph: rename kvec_reset and kvec_add functionsAlex Elder
The functions ceph_con_out_kvec_reset() and ceph_con_out_kvec_add() are entirely private functions, so drop the "ceph_" prefix in their name to make them slightly more wieldy. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-01libceph: rename socket callbacksAlex Elder
Change the names of the three socket callback functions to make it more obvious they're specifically associated with a connection's socket (not the ceph connection that uses it). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-06-01libceph: kill bad_proto ceph connection opAlex Elder
No code sets a bad_proto method in its ceph connection operations vector, so just get rid of it. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-06-01libceph: eliminate connection state "DEAD"Alex Elder
The ceph connection state "DEAD" is never set and is therefore not needed. Eliminate it. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
2012-05-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-clientLinus Torvalds
Pull ceph updates from Sage Weil: "There are some updates and cleanups to the CRUSH placement code, a bug fix with incremental maps, several cleanups and fixes from Josh Durgin in the RBD block device code, a series of cleanups and bug fixes from Alex Elder in the messenger code, and some miscellaneous bounds checking and gfp cleanups/fixes." Fix up trivial conflicts in net/ceph/{messenger.c,osdmap.c} due to the networking people preferring "unsigned int" over just "unsigned". * git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (45 commits) libceph: fix pg_temp updates libceph: avoid unregistering osd request when not registered ceph: add auth buf in prepare_write_connect() ceph: rename prepare_connect_authorizer() ceph: return pointer from prepare_connect_authorizer() ceph: use info returned by get_authorizer ceph: have get_authorizer methods return pointers ceph: ensure auth ops are defined before use ceph: messenger: reduce args to create_authorizer ceph: define ceph_auth_handshake type ceph: messenger: check return from get_authorizer ceph: messenger: rework prepare_connect_authorizer() ceph: messenger: check prepare_write_connect() result ceph: don't set WRITE_PENDING too early ceph: drop msgr argument from prepare_write_connect() ceph: messenger: send banner in process_connect() ceph: messenger: reset connection kvec caller libceph: don't reset kvec in prepare_write_banner() ceph: ignore preferred_osd field ceph: fully initialize new layout ...
2012-05-18ceph: add auth buf in prepare_write_connect()Alex Elder
Move the addition of the authorizer buffer to a connection's out_kvec out of get_connect_authorizer() and into its caller. This way, the caller--prepare_write_connect()--can avoid adding the connect header to out_kvec before it has been fully initialized. Prior to this patch, it was possible for a connect header to be sent over the wire before the authorizer protocol or buffer length fields were initialized. An authorizer buffer associated with that header could also be queued to send only after the connection header that describes it was on the wire. Fixes http://tracker.newdream.net/issues/2424 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: rename prepare_connect_authorizer()Alex Elder
Change the name of prepare_connect_authorizer(). The next patch is going to make this function no longer add anything to the connection's out_kvec, so it will no longer fit the pattern of the rest of the prepare_connect_*() functions. In addition, pass the address of a variable that will hold the authorization protocol to use. Move the assignment of that to the connection's out_connect structure into prepare_write_connect(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: return pointer from prepare_connect_authorizer()Alex Elder
Change prepare_connect_authorizer() so it returns a pointer (or pointer-coded error). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: use info returned by get_authorizerAlex Elder
Rather than passing a bunch of arguments to be filled in with the content of the ceph_auth_handshake buffer now returned by the get_authorizer method, just use the returned information in the caller, and drop the unnecessary arguments. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: have get_authorizer methods return pointersAlex Elder
Have the get_authorizer auth_client method return a ceph_auth pointer rather than an integer, pointer-encoding any returned error value. This is to pave the way for making use of the returned value in an upcoming patch. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: messenger: check return from get_authorizerAlex Elder
In prepare_connect_authorizer(), a connection's get_authorizer method is called but ignores its return value. This function can return an error, so check for it and return it if that ever occurs. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: messenger: rework prepare_connect_authorizer()Alex Elder
Change prepare_connect_authorizer() so it returns without dropping the connection mutex if the connection has no get_authorizer method. Use the symbolic CEPH_AUTH_UNKNOWN instead of 0 when assigning authorization protocols. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: messenger: check prepare_write_connect() resultAlex Elder
prepare_write_connect() can return an error, but only one of its callers checks for it. All the rest are in functions that already return errors, so it should be fine to return the error if one gets returned. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: don't set WRITE_PENDING too earlyAlex Elder
prepare_write_connect() prepares a connect message, then sets WRITE_PENDING on the connection. Then *after* this, it calls prepare_connect_authorizer(), which updates the content of the connection buffer already queued for sending. It's also possible it will result in prepare_write_connect() returning -EAGAIN despite the WRITE_PENDING big getting set. Fix this by preparing the connect authorizer first, setting the WRITE_PENDING bit only after that is done. Partially addresses http://tracker.newdream.net/issues/2424 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: drop msgr argument from prepare_write_connect()Alex Elder
In all cases, the value passed as the msgr argument to prepare_write_connect() is just con->msgr. Just get the msgr value from the ceph connection and drop the unneeded argument. The only msgr passed to prepare_write_banner() is also therefore just the one from con->msgr, so change that function to drop the msgr argument as well. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: messenger: send banner in process_connect()Alex Elder
prepare_write_connect() has an argument indicating whether a banner should be sent out before sending out a connection message. It's only ever set in one of its callers, so move the code that arranges to send the banner into that caller and drop the "include_banner" argument from prepare_write_connect(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17ceph: messenger: reset connection kvec callerAlex Elder
Reset a connection's kvec fields in the caller rather than in prepare_write_connect(). This ends up repeating a few lines of code but it's improving the separation between distinct operations on the connection, which we can take advantage of later. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-17libceph: don't reset kvec in prepare_write_banner()Alex Elder
Move the kvec reset for a connection out of prepare_write_banner and into its only caller. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-14ceph: messenger: change read_partial() to take "end" argAlex Elder
Make the second argument to read_partial() be the ending input byte position rather than the beginning offset it now represents. This amounts to moving the addition "to + size" into the caller. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-14ceph: messenger: update "to" in read_partial() callerAlex Elder
read_partial() always increases whatever "to" value is supplied by adding the requested size to it, and that's the only thing it does with that pointed-to value. Do that pointer advance in the caller (and then only when the updated value will be subsequently used), and change the "to" parameter to be an in-only and non-pointer value. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-05-14ceph: messenger: use read_partial() in read_partial_message()Alex Elder
There are two blocks of code in read_partial_message()--those that read the header and footer of the message--that can be replaced by a call to read_partial(). Do that. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2012-04-15net: cleanup unsigned to unsigned intEric Dumazet
Use of "unsigned int" is preferred to bare "unsigned" in net tree. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-22libceph: isolate kmap() call in write_partial_msg_pages()Alex Elder
In write_partial_msg_pages(), every case now does an identical call to kmap(page). Instead, just call it once inside the CRC-computing block where it's needed. Move the definition of kaddr inside that block, and make it a (char *) to ensure portable pointer arithmetic. We still don't kunmap() it until after the sendpage() call, in case that also ends up needing to use the mapping. Signed-off-by: Alex Elder <elder@dreamhost.com> Reviewed-by: Sage Weil <sage@newdream.net>
2012-03-22libceph: rename "page_shift" variable to something sensibleAlex Elder
In write_partial_msg_pages() there is a local variable used to track the starting offset within a bio segment to use. Its name, "page_shift" defies the Linux convention of using that name for log-base-2(page size). Since it's only used in the bio case rename it "bio_offset". Use it along with the page_pos field to compute the memory offset when computing CRC's in that function. This makes the bio case match the others more closely. Signed-off-by: Alex Elder <elder@dreamhost.com> Reviewed-by: Sage Weil <sage@newdream.net>