summaryrefslogtreecommitdiff
path: root/net/ceph/messenger.c
AgeCommit message (Collapse)AuthorFilesLines
2013-05-02libceph: allocate ceph message data with a slab allocatorAlex Elder1-3/+23
Create a slab cache to manage ceph_msg_data structure allocation. This is part of: http://tracker.ceph.com/issues/3926 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-02libceph: allocate ceph messages with a slab allocatorAlex Elder1-2/+27
Create a slab cache to manage ceph_msg structure allocation. This is part of: http://tracker.ceph.com/issues/3926 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: fix two messenger bugsAlex Elder1-5/+3
This patch makes four small changes in the ceph messenger. While getting copyup functionality working I found two bugs in the messenger. Existing paths through the code did not trigger these problems, but they're fixed here: - In ceph_msg_data_pagelist_cursor_init(), the cursor's last_piece field was being checked against the length supplied. This was OK until this commit: ccba6d98 libceph: implement multiple data items in a message That commit changed the cursor init routines to allow lengths to be supplied that exceeded the size of the current data item. Because of this, we have to use the assigned cursor resid field rather than the provided length in determining whether the cursor points to the last piece of a data item. - In ceph_msg_data_add_pages(), a BUG_ON() was erroneously catching attempts to add page data to a message if the message already had data assigned to it. That was OK until that same commit, at which point it was fine for messages to have multiple data items. It slipped through because that BUG_ON() call was present twice in that function. (You can never be too careful.) In addition two other minor things are changed: - In ceph_msg_data_cursor_init(), the local variable "data" was getting assigned twice. - In ceph_msg_data_advance(), it was assumed that the type-specific advance routine would set new_piece to true after it advanced past the last piece. That may have been fine, but since we check for that case we might as well set it explicitly in ceph_msg_data_advance(). This resolves: http://tracker.ceph.com/issues/4762 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: add, don't set data for a messageAlex Elder1-6/+6
Change the names of the functions that put data on a pagelist to reflect that we're adding to whatever's already there rather than just setting it to the one thing. Currently only one data item is ever added to a message, but that's about to change. This resolves: http://tracker.ceph.com/issues/2770 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: implement multiple data items in a messageAlex Elder1-16/+32
This patch adds support to the messenger for more than one data item in its data list. A message data cursor has two more fields to support this: - a count of the number of bytes left to be consumed across all data items in the list, "total_resid" - a pointer to the head of the list (for validation only) The cursor initialization routine has been split into two parts: the outer one, which initializes the cursor for traversing the entire list of data items; and the inner one, which initializes the cursor to start processing a single data item. When a message cursor is first initialized, the outer initialization routine sets total_resid to the length provided. The data pointer is initialized to the first data item on the list. From there, the inner initialization routine finishes by setting up to process the data item the cursor points to. Advancing the cursor consumes bytes in total_resid. If the resid field reaches zero, it means the current data item is fully consumed. If total_resid indicates there is more data, the cursor is advanced to point to the next data item, and then the inner initialization routine prepares for using that. (A check is made at this point to make sure we don't wrap around the front of the list.) The type-specific init routines are modified so they can be given a length that's larger than what the data item can support. The resid field is initialized to the smaller of the provided length and the length of the entire data item. When total_resid reaches zero, we're done. This resolves: http://tracker.ceph.com/issues/3761 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: replace message data pointer with listAlex Elder1-15/+31
In place of the message data pointer, use a list head which links through message data items. For now we only support a single entry on that list. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: have cursor point to dataAlex Elder1-58/+55
Rather than having a ceph message data item point to the cursor it's associated with, have the cursor point to a data item. This will allow a message cursor to be used for more than one data item. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: move cursor into messageAlex Elder1-16/+19
A message will only be processing a single data item at a time, so there's no need for each data item to have its own cursor. Move the cursor embedded in the message data structure into the message itself. To minimize the impact, keep the data->cursor field, but make it be a pointer to the cursor in the message. Move the definition of ceph_msg_data above ceph_msg_data_cursor so the cursor can point to the data without a forward definition rather than vice-versa. This and the upcoming patches are part of: http://tracker.ceph.com/issues/3761 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: record bio lengthAlex Elder1-0/+1
The bio is the only data item type that doesn't record its full length. Fix that. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: skip message if too big to receiveAlex Elder1-1/+9
We know the length of our message buffers. If we get a message that's too long, just dump it and ignore it. If skip was set then con->in_msg won't be valid, so be careful not to dereference a null pointer in the process. This resolves: http://tracker.ceph.com/issues/4664 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: fix possible CONFIG_BLOCK build problemAlex Elder1-1/+3
This patch: 15a0d7b libceph: record message data length did not enclose some bio-specific code inside CONFIG_BLOCK as it should have. Fix that. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: provide data length when preparing messageAlex Elder1-11/+8
In prepare_message_data(), the length used to initialize the cursor is taken from the header of the message provided. I'm working toward not using the header data length field to determine length in outbound messages, and this is a step in that direction. For inbound messages this will be set to be the actual number of bytes that are arriving (which may be less than the total size of the data buffer available). This resolves: http://tracker.ceph.com/issues/4589 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: record message data lengthAlex Elder1-1/+9
Keep track of the length of the data portion for a message in a separate field in the ceph_msg structure. This information has been maintained in wire byte order in the message header, but that's going to change soon. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: account for alignment in pages cursorAlex Elder1-3/+4
When a cursor for a page array data message is initialized it needs to determine the initial value for cursor->last_piece. Currently it just checks if length is less than a page, but that's not correct. The data in the first page in the array will be offset by a page offset based on the alignment recorded for the data. (All pages thereafter will be aligned at the base of the page, so there's no need to account for this except for the first page.) Because this was wrong, there was a case where the length of a piece would be calculated as all of the residual bytes in the message and that plus the page offset could exceed the length of a page. So fix this case. Make sure the sum won't wrap. This resolves a third issue described in: http://tracker.ceph.com/issues/4598 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-05-01libceph: page offset must be less than page sizeAlex Elder1-7/+7
Currently ceph_msg_data_pages_advance() allows the page offset value to be PAGE_SIZE, apparently assuming ceph_msg_data_pages_next() will treat it as 0. But that doesn't happen, and the result led to a helpful assertion failure. Change ceph_msg_data_pages_advance() to truncate the offset to 0 before returning if it reaches PAGE_SIZE. Make a few other minor adjustments in this area (comments and a better assertion) while modifying it. This resolves a second issue described in: http://tracker.ceph.com/issues/4598 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-05-01libceph: fix broken data length assertionsAlex Elder1-2/+2
It's OK for the result of a read to come back with fewer bytes than were requested. So don't trigger a BUG() in that case when initializing the data cursor. This resolves the first problem described in: http://tracker.ceph.com/issues/4598 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-05-01libceph: make message data be a pointerAlex Elder1-33/+61
Begin the transition from a single message data item to a list of them by replacing the "data" structure in a message with a pointer to a ceph_msg_data structure. A null pointer will indicate the message has no data; replace the use of ceph_msg_has_data() with a simple check for a null pointer. Create functions ceph_msg_data_create() and ceph_msg_data_destroy() to dynamically allocate and free a data item structure of a given type. When a message has its data item "set," allocate one of these to hold the data description, and free it when the last reference to the message is dropped. This partially resolves: http://tracker.ceph.com/issues/4429 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: use only ceph_msg_data_advance()Alex Elder1-36/+3
The *_msg_pos_next() functions do little more than call ceph_msg_data_advance(). Replace those wrapper functions with a simple call to ceph_msg_data_advance(). This cleanup is related to: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: don't add to crc unless data sentAlex Elder1-2/+2
In write_partial_message_data() we aggregate the crc for the data portion of the message as each new piece of the data item is encountered. Because it was computed *before* sending the data, if an attempt to send a new piece resulted in 0 bytes being sent, the crc crc across that piece would erroneously get computed again and added to the aggregate result. This would occasionally happen in the evnet of a connection failure. The crc value isn't really needed until the complete value is known after sending all data, so there's no need to compute it before sending. So don't calculate the crc for a piece until *after* we know at least one byte of it has been sent. That will avoid this problem. This resolves: http://tracker.ceph.com/issues/4450 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-05-01libceph: kill last of ceph_msg_posAlex Elder1-25/+31
The only remaining field in the ceph_msg_pos structure is did_page_crc. In the new cursor model of things that flag (or something like it) belongs in the cursor. Define a new field "need_crc" in the cursor (which applies to all types of data) and initialize it to true whenever a cursor is initialized. In write_partial_message_data(), the data CRC still will be computed as before, but it will check the cursor->need_crc field to determine whether it's needed. Any time the cursor is advanced to a new piece of a data item, need_crc will be set, and this will cause the crc for that entire piece to be accumulated into the data crc. In write_partial_message_data() the intermediate crc value is now held in a local variable so it doesn't have to be byte-swapped so many times. In read_partial_msg_data() we do something similar (but mainly for consistency there). With that, the ceph_msg_pos structure can go away, and it no longer needs to be passed as an argument to prepare_message_data(). This cleanup is related to: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: kill most of ceph_msg_posAlex Elder1-21/+1
All but one of the fields in the ceph_msg_pos structure are now never used (only assigned), so get rid of them. This allows several small blocks of code to go away. This is cleanup of old code related to: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: use cursor resid for loop conditionAlex Elder1-5/+4
Use the "resid" field of a cursor rather than finding when the message data position has moved up to meet the data length to determine when all data has been sent or received in write_partial_message_data() and read_partial_msg_data(). This is cleanup of old code related to: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: collapse all data items into oneAlex Elder1-85/+38
It turns out that only one of the data item types is ever used at any one time in a single message (currently). - A page array is used by the osd client (on behalf of the file system) and by rbd. Only one osd op (and therefore at most one data item) is ever used at a time by rbd. And the only time the file system sends two, the second op contains no data. - A bio is only used by the rbd client (and again, only one data item per message) - A page list is used by the file system and by rbd for outgoing data, but only one op (and one data item) at a time. We can therefore collapse all three of our data item fields into a single field "data", and depend on the messenger code to properly handle it based on its type. This allows us to eliminate quite a bit of duplicated code. This is related to: http://tracker.ceph.com/issues/4429 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: get rid of read helpersAlex Elder1-62/+18
Now that read_partial_message_pages() and read_partial_message_bio() are literally identical functions we can factor them out. They're pretty simple as well, so just move their relevant content into read_partial_msg_data(). This is and previous patches together resolve: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: no outbound zero dataAlex Elder1-7/+4
There is handling in write_partial_message_data() for the case where only the length of--and no other information about--the data to be sent has been specified. It uses the zero page as the source of data to send in this case. This case doesn't occur. All message senders set up a page array, pagelist, or bio describing the data to be sent. So eliminate the block of code that handles this (but check and issue a warning for now, just in case it happens for some reason). This resolves: http://tracker.ceph.com/issues/4426 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: use cursor for inbound data pagesAlex Elder1-13/+4
The cursor code for a page array selects the right page, page offset, and length to use for a ceph_tcp_recvpage() call, so we can use it to replace a block in read_partial_message_pages(). This partially resolves: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: kill ceph message bio_iter, bio_segAlex Elder1-31/+0
The bio_iter and bio_seg fields in a message are no longer used, we use the cursor instead. So get rid of them and the functions that operate on them them. This is related to: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: use cursor for bio readsAlex Elder1-11/+6
Replace the use of the information in con->in_msg_pos for incoming bio data. The old in_msg_pos and the new cursor mechanism do basically the same thing, just slightly differently. The main functional difference is that in_msg_pos keeps track of the length of the complete bio list, and assumed it was fully consumed when that many bytes had been transferred. The cursor does not assume a length, it simply consumes all bytes in the bio list. Because the only user of bio data is the rbd client, and because the length of a bio list provided by rbd client always matches the number of bytes in the list, both ways of tracking length are equivalent. In addition, for in_msg_pos the initial bio vector is selected as the initial value of the bio->bi_idx, while the cursor assumes this is zero. Again, the rbd client always passes 0 as the initial index so the effect is the same. Other than that, they basically match: in_msg_pos cursor ---------- ------ bio_iter bio bio_seg vec_index page_pos page_offset The in_msg_pos field is initialized by a call to init_bio_iter(). The bio cursor is initialized by ceph_msg_data_cursor_init(). Both now happen in the same spot, in prepare_message_data(). The in_msg_pos field is advanced by a call to in_msg_pos_next(), which updates page_pos and calls iter_bio_next() to move to the next bio vector, or to the next bio in the list. The cursor is advanced by ceph_msg_data_advance(). That isn't currently happening so add a call to that in in_msg_pos_next(). Finally, the next piece of data to use for a read is determined by a bunch of lines in read_partial_message_bio(). Those can be replaced by an equivalent ceph_msg_data_bio_next() call. This partially resolves: http://tracker.ceph.com/issues/4428 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: record residual bytes for all message data typesAlex Elder1-49/+62
All of the data types can use this, not just the page array. Until now, only the bio type doesn't have it available, and only the initiator of the request (the rbd client) is able to supply the length of the full request without re-scanning the bio list. Change the cursor init routines so the length is supplied based on the message header "data_len" field, and use that length to intiialize the "resid" field of the cursor. In addition, change the way "last_piece" is defined so it is based on the residual number of bytes in the original request. This is necessary (at least for bio messages) because it is possible for a read request to succeed without consuming all of the space available in the data buffer. This resolves: http://tracker.ceph.com/issues/4427 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: drop pages parameterAlex Elder1-3/+5
The value passed for "pages" in read_partial_message_pages() is always the pages pointer from the incoming message, which can be derived inside that function. So just get rid of the parameter. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: initialize data fields on last msg putAlex Elder1-1/+6
When the last reference to a ceph message is dropped, ceph_msg_last_put() is called to clean things up. For "normal" messages (allocated via ceph_msg_new() rather than being allocated from a memory pool) it's sufficient to just release resources. But for a mempool-allocated message we actually have to re-initialize the data fields in the message back to initial state so they're ready to go in the event the message gets reused. Some of this was already done; this fleshes it out so it's done more completely. This resolves: http://tracker.ceph.com/issues/4540 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: clear messenger auth_retry flag when we authenticateSage Weil1-2/+1
We maintain a counter of failed auth attempts to allow us to retry once before failing. However, if the second attempt succeeds, the flag isn't cleared, which makes us think auth failed again later when the connection resets for other reasons (like a socket error). This is one part of the sorry sequence of events in bug http://tracker.ceph.com/issues/4282 Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2013-05-01libceph: implement RECONNECT_SEQ featureSage Weil1-5/+38
This is an old protocol extension that allows the client and server to avoid resending old messages after a reconnect (following a socket error). Instead, the exchange their sequence numbers during the handshake. This avoids sending a bunch of useless data over the socket. It has been supported in the server code since v0.22 (Sep 2010). Signed-off-by: Sage Weil <sage@inktank.com> Reviewed-by: Alex Elder <elder@inktank.com>
2013-05-01libceph: more cleanup of write_partial_msg_pages()Alex Elder1-14/+7
Basically all cases in write_partial_msg_pages() use the cursor, and as a result we can simplify that function quite a bit. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: kill message trailAlex Elder1-39/+5
The wart that is the ceph message trail can now be removed, because its only user was the osd client, and the previous patch made that no longer the case. The result allows write_partial_msg_pages() to be simplified considerably. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: implement pages array cursorAlex Elder1-4/+89
Implement and use cursor routines for page array message data items for outbound message data. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: implement bio message data item cursorAlex Elder1-21/+116
Implement and use cursor routines for bio message data items for outbound message data. (See the previous commit for reasoning in support of the changes in out_msg_pos_next().) Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: use data cursor for message pagelistAlex Elder1-12/+13
Switch to using the message cursor for the (non-trail) outgoing pagelist data item in a message if present. Notes on the logic changes in out_msg_pos_next(): - only the mds client uses a ceph pagelist for message data; - if the mds client ever uses a pagelist, it never uses a page array (or anything else, for that matter) for data in the same message; - only the osd client uses the trail portion of a message data, and when it does, it never uses any other data fields for outgoing data in the same message; and finally - only the rbd client uses bio message data (never pagelist). Therefore out_msg_pos_next() can assume: - if we're in the trail portion of a message, the message data pagelist, data, and bio can be ignored; and - if there is a page list, there will never be any a bio or page array data, and vice-versa. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: prepare for other message data item typesAlex Elder1-24/+93
This just inserts some infrastructure in preparation for handling other types of ceph message data items. No functional changes, just trying to simplify review by separating out some noise. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: start defining message data cursorAlex Elder1-10/+128
This patch lays out the foundation for using generic routines to manage processing items of message data. For simplicity, we'll start with just the trail portion of a message, because it stands alone and is only present for outgoing data. First some basic concepts. We'll use the term "data item" to represent one of the ceph_msg_data structures associated with a message. There are currently four of those, with single-letter field names p, l, b, and t. A data item is further broken into "pieces" which always lie in a single page. A data item will include a "cursor" that will track state as the memory defined by the item is consumed by sending data from or receiving data into it. We define three routines to manipulate a data item's cursor: the "init" routine; the "next" routine; and the "advance" routine. The "init" routine initializes the cursor so it points at the beginning of the first piece in the item. The "next" routine returns the page, page offset, and length (limited by both the page and item size) of the next unconsumed piece in the item. It also indicates to the caller whether the piece being returned is the last one in the data item. The "advance" routine consumes the requested number of bytes in the item (advancing the cursor). This is used to record the number of bytes from the current piece that were actually sent or received by the network code. It returns an indication of whether the result means the current piece has been fully consumed. This is used by the message send code to determine whether it should calculate the CRC for the next piece processed. The trail of a message is implemented as a ceph pagelist. The routines defined for it will be usable for non-trail pagelist data as well. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: abstract message dataAlex Elder1-10/+23
Group the types of message data into an abstract structure with a type indicator and a union containing fields appropriate to the type of data it represents. Use this to represent the pages, pagelist, bio, and trail in a ceph message. Verify message data is of type NONE in ceph_msg_data_set_*() routines. Since information about message data of type NONE really should not be interpreted, get rid of the other assertions in those functions. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: be explicit about message data representationAlex Elder1-34/+34
A ceph message has a data payload portion. The memory for that data (either the source of data to send or the location to place data that is received) is specified in several ways. The ceph_msg structure includes fields for all of those ways, but this mispresents the fact that not all of them are used at a time. Specifically, the data in a message can be in: - an array of pages - a list of pages - a list of Linux bios - a second list of pages (the "trail") (The two page lists are currently only ever used for outgoing data.) Impose more structure on the ceph message, making the grouping of some of these fields explicit. Shorten the name of the "page_alignment" field. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: define ceph_msg_has_*() data macrosAlex Elder1-17/+27
Define and use macros ceph_msg_has_*() to determine whether to operate on the pages, pagelist, bio, and trail fields of a message. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: define and use ceph_crc32c_page()Alex Elder1-27/+20
Factor out a common block of code that updates a CRC calculation over a range of data in a page. This and the preceding patches are related to: http://tracker.ceph.com/issues/4403 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: define and use ceph_tcp_recvpage()Alex Elder1-26/+60
Define a new function ceph_tcp_recvpage() that behaves in a way comparable to ceph_tcp_sendpage(). Rearrange the code in both read_partial_message_pages() and read_partial_message_bio() so they have matching structure, (similar to what's in write_partial_msg_pages()), and use this new function. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: encapsulate reading message dataAlex Elder1-22/+41
Pull the code that reads the data portion into a message into a separate function read_partial_msg_data(). Rename write_partial_msg_pages() to be write_partial_message_data() to match its read counterpart, and to reflect its more generic purpose. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: small write_partial_msg_pages() refactorAlex Elder1-8/+9
Define local variables page_offset and length to represent the range of bytes within a page that will be sent by ceph_tcp_sendpage() in write_partial_msg_pages(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: consolidate message prep codeAlex Elder1-18/+10
In prepare_write_message_data(), various fields are initialized in preparation for writing message data out. Meanwhile, in read_partial_message(), there is essentially the same block of code, operating on message variables associated with an incoming message. Generalize prepare_write_message_data() so it works for both incoming and outcoming messages, and use it in both spots. The did_page_crc is not used for input (so it's harmless to initialize it). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: use local variables for message positionsAlex Elder1-39/+46
There are several places where a message's out_msg_pos or in_msg_pos field is used repeatedly within a function. Use a local pointer variable for this purpose to unclutter the code. This and the upcoming cleanup patches are related to: http://tracker.ceph.com/issues/4403 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: don't clear bio_iter in prepare_write_message()Alex Elder1-4/+0
At one time it was necessary to clear a message's bio_iter field to avoid a bad pointer dereference in write_partial_msg_pages(). That no longer seems to be the case. Here's why. The message's bio fields represent (in this case) outgoing data. Between where the bio_iter is made NULL in prepare_write_message() and the call in that function to prepare_message_data(), the bio fields are never used. In prepare_message_data(), init-bio_iter() is called, and the result of that overwrites the value in the message's bio_iter field. Because it gets overwritten anyway, there is no need to set it to NULL. So don't do it. This resolves: http://tracker.ceph.com/issues/4402 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>