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2013-05-01libceph: define and use ceph_tcp_recvpage()Alex Elder
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 Elder
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 Elder
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 Elder
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 Elder
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 Elder
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>
2013-05-01libceph: activate message data assignment checksAlex Elder
The mds client no longer tries to assign zero-length message data, and the osd client no longer sets its data info more than once. This allows us to activate assertions in the messenger to verify these things never happen. This resolves both of these: http://tracker.ceph.com/issues/4263 http://tracker.ceph.com/issues/4284 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01libceph: set response data fields earlierAlex Elder
When an incoming message is destined for the osd client, the messenger calls the osd client's alloc_msg method. That function looks up which request has the tid matching the incoming message, and returns the request message that was preallocated to receive the response. The response message is therefore known before the request is even started. Between the start of the request and the receipt of the response, the request and its data fields will not change, so there's no reason we need to hold off setting them. In fact it's preferable to set them just once because it's more obvious that they're unchanging. So set up the fields describing where incoming data is to land in a response message at the beginning of ceph_osdc_start_request(). Define a helper function that sets these fields, and use it to set the fields for both outgoing data in the request message and incoming data in the response. This resolves: http://tracker.ceph.com/issues/4284 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: record message data byte lengthAlex Elder
Record the number of bytes of data in a page array rather than the number of pages in the array. It can be assumed that the page array is of sufficient size to hold the number of bytes indicated (and offset by the indicated alignment). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01ceph: only set message data pointers if non-emptyAlex Elder
Change it so we only assign outgoing data information for messages if there is outgoing data to send. This then allows us to add a few more (currently commented-out) assertions. This is related to: http://tracker.ceph.com/issues/4284 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01libceph: isolate other message data fieldsAlex Elder
Define ceph_msg_data_set_pagelist(), ceph_msg_data_set_bio(), and ceph_msg_data_set_trail() to clearly abstract the assignment of the remaining data-related fields in a ceph message structure. Use the new functions in the osd client and mds client. This partially resolves: http://tracker.ceph.com/issues/4263 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: set page info with byte lengthAlex Elder
When setting page array information for message data, provide the byte length rather than the page count ceph_msg_data_set_pages(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: isolate message page field manipulationAlex Elder
Define a function ceph_msg_data_set_pages(), which more clearly abstracts the assignment page-related fields for data in a ceph message structure. Use this new function in the osd client and mds client. Ideally, these fields would never be set more than once (with BUG_ON() calls to guarantee that). At the moment though the osd client sets these every time it receives a message, and in the event of a communication problem this can happen more than once. (This will be resolved shortly, but setting up these helpers first makes it all a bit easier to work with.) Rearrange the field order in a ceph_msg structure to group those that are used to define the possible data payloads. This partially resolves: http://tracker.ceph.com/issues/4263 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: record byte count not page countAlex Elder
Record the byte count for an osd request rather than the page count. The number of pages can always be derived from the byte count (and alignment/offset) but the reverse is not true. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: simplify new message initializationAlex Elder
Rather than explicitly initializing many fields to 0, NULL, or false in a newly-allocated message, just use kzalloc() for allocating new messages. This will become a much more convenient way of doing things anyway for upcoming patches that abstract the data field. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: advance pagelist with list_rotate_left()Alex Elder
While processing an outgoing pagelist (either the data pagelist or trail) in a ceph message, the messenger cycles through each of the pages on the list. This is accomplished in out_msg_pos_next(), if the end of the first page on the list is reached, the first page is moved to the end of the list. There is a list operation, list_rotate_left(), which performs exactly this operation, and by using it, what's really going on becomes more obvious. So replace these two list_move_tail() calls with list_rotate_left(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: define and use in_msg_pos_next()Alex Elder
Define a new function in_msg_pos_next() to match out_msg_pos_next(), and use it in place of code at the end of read_partial_message_pages() and read_partial_message_bio(). Note that the page number is incremented and offset reset under slightly different conditions from before. The result is equivalent, however, as explained below. Each time an incoming message is going to arrive, we find out how much room is left--not surpassing the current page--and provide that as the number of bytes to receive. So the amount we'll use is the lesser of: all that's left of the entire request; and all that's left in the current page. If we received exactly how many were requested, we either reached the end of the request or the end of the page. In the first case, we're done, in the second, we move onto the next page in the array. In all cases but (possibly) on the last page, after adding the number of bytes received, page_pos == PAGE_SIZE. On the last page, it doesn't really matter whether we increment the page number and reset the page position, because we're done and we won't come back here again. The code previously skipped over that last case, basically. The new code handles that case the same as the others, incrementing and resetting. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: kill args in read_partial_message_bio()Alex Elder
There is only one caller for read_partial_message_bio(), and it always passes &msg->bio_iter and &bio_seg as the second and third arguments. Furthermore, the message in question is always the connection's in_msg, and we can get that inside the called function. So drop those two parameters and use their derived equivalents. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: change type of ceph_tcp_sendpage() "more"Alex Elder
Change the type of the "more" parameter from int to bool. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: minor byte order problems in read_partial_message()Alex Elder
Some values printed are not (necessarily) in CPU order. We already have a copy of the converted versions, so use them. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: define CEPH_MSG_MAX_MIDDLE_LENAlex Elder
This is probably unnecessary but the code read as if it were wrong in read_partial_message(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: clean up skipped message logicAlex Elder
In ceph_con_in_msg_alloc() it is possible for a connection's alloc_msg method to indicate an incoming message should be skipped. By default, read_partial_message() initializes the skip variable to 0 before it gets provided to ceph_con_in_msg_alloc(). The osd client, mon client, and mds client each supply an alloc_msg method. The mds client always assigns skip to be 0. The other two leave the skip value of as-is, or assigns it to zero, except: - if no (osd or mon) request having the given tid is found, in which case skip is set to 1 and NULL is returned; or - in the osd client, if the data of the reply message is not adequate to hold the message to be read, it assigns skip value 1 and returns NULL. So the returned message pointer will always be NULL if skip is ever non-zero. Clean up the logic a bit in ceph_con_in_msg_alloc() to make this state of affairs more obvious. Add a comment explaining how a null message pointer can mean either a message that should be skipped or a problem allocating a message. This resolves: http://tracker.ceph.com/issues/4324 Reported-by: Greg Farnum <greg@inktank.com> Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01libceph: separate read and write dataAlex Elder
An osd request defines information about where data to be read should be placed as well as where data to write comes from. Currently these are represented by common fields. Keep information about data for writing separate from data to be read by splitting these into data_in and data_out fields. This is the key patch in this whole series, in that it actually identifies which osd requests generate outgoing data and which generate incoming data. It's less obvious (currently) that an osd CALL op generates both outgoing and incoming data; that's the focus of some upcoming work. This resolves: http://tracker.ceph.com/issues/4127 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: distinguish page and bio requestsAlex Elder
An osd request uses either pages or a bio list for its data. Use a union to record information about the two, and add a data type tag to select between them. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: separate osd request data infoAlex Elder
Pull the fields in an osd request structure that define the data for the request out into a separate structure. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: don't assign page info in ceph_osdc_new_request()Alex Elder
Currently ceph_osdc_new_request() assigns an osd request's r_num_pages and r_alignment fields. The only thing it does after that is call ceph_osdc_build_request(), and that doesn't need those fields to be assigned. Move the assignment of those fields out of ceph_osdc_new_request() and into its caller. As a result, the page_align parameter is no longer used, so get rid of it. Note that in ceph_sync_write(), the value for req->r_num_pages had already been calculated earlier (as num_pages, and fortunately it was computed the same way). So don't bother recomputing it, but because it's not needed earlier, move that calculation after the call to ceph_osdc_new_request(). Hold off making the assignment to r_alignment, doing it instead r_pages and r_num_pages are getting set. Similarly, in start_read(), nr_pages already holds the number of pages in the array (and is calculated the same way), so there's no need to recompute it. Move the assignment of the page alignment down with the others there as well. This and the next few patches are preparation work for: http://tracker.ceph.com/issues/4127 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01ceph: simplify ceph_sync_write() page_align calculationAlex Elder
(This is being reposted. The first one had a problem because it erroneously added a similar change elsewhere; that change has been dropped.) The next patch in this series points out that the calculation for the number of pages in an osd request is getting done twice. It is not obvious, but the result of both calculations is identical. This patch simplifies one of them--as a separate step--to make it clear that the transformation in the next patch is valid. In ceph_sync_write() there is some magic that computes page_align for an osd request. But a little analysis shows it can be simplified. First, we have: io_align = pos & ~PAGE_MASK; which is used here: page_align = (pos - io_align + buf_align) & ~PAGE_MASK; Note (pos - io_align) simply rounds "pos" down to the nearest multiple of the page size. We also have: buf_align = (unsigned long)data & ~PAGE_MASK; Adding buf_align to that rounded-down "pos" value will stay within the same page; the result will just be offset by the page offset for the "data" pointer. The final mask therefore leaves just the value of "buf_align". One more simplification. Note that the result of calc_pages_for() is invariant of which page the offset starts in--the only thing that matters is the offset within the starting page. We will have put the proper page offset to use into "page_align", so just use that in calculating num_pages. This resolves: http://tracker.ceph.com/issues/4166 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01ceph: use calc_pages_for() in start_read()Alex Elder
There's a spot that computes the number of pages to allocate for a page-aligned length by just shifting it. Use calc_pages_for() instead, to be consistent with usage everywhere else. The result is the same. The reason for this is to make it clearer in an upcoming patch that this calculation is duplicated. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: no need for alignment for mds messageAlex Elder
Currently, incoming mds messages never use page data, which means there is no need to set the page_alignment field in the message. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01libceph: define mds_alloc_msg() methodAlex Elder
The only user of the ceph messenger that doesn't define an alloc_msg method is the mds client. Define one, such that it works just like it did before, and simplify ceph_con_in_msg_alloc() by assuming the alloc_msg method is always present. This and the next patch resolve: http://tracker.ceph.com/issues/4322 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01libceph: drop mutex while allocating a messageAlex Elder
In ceph_con_in_msg_alloc(), if no alloc_msg method is defined for a connection a new message is allocated with ceph_msg_new(). Drop the mutex before making this call, and make sure we're still connected when we get it back again. This is preparing for the next patch, which ensures all connections define an alloc_msg method, and then handles them all the same way. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01libceph: rename ceph_calc_object_layout()Alex Elder
The purpose of ceph_calc_object_layout() is to fill in the pool number and seed for a ceph_pg structure provided, based on a given osd map and target object id. Currently that function takes a file layout parameter, but the only thing used out of that is its pool number. Change the function so it takes a pool number rather than the full file layout structure. Only update the ceph_pg if the pool is found in the osd map. Get rid of few useless lines of code from the function while there. Since the function now very clearly just fills in the ceph_pg structure it's provided, rename it ceph_calc_ceph_pg(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: kill ceph_msg->pagelist_countAlex Elder
The pagelist_count field is never actually used, so get rid of it. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: use (void *) for untyped data in osd opsAlex Elder
Two of the fields defining osd operations are defined using (char *) while the data they represent are really untyped, not character strings. Change them to have type (void *). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: fix wrong opcode use in osd_req_encode_op()Alex Elder
The new cases added to osd_req_encode_op() caused a new sparse error, which highlighted an existing problem that had been overlooked since it was originally checked in. When an unsupported opcode is found the destination rather than the source opcode was being used in the error message. The two differ in their byte order, and we want to be using the one in the source. Fix the problem in both spots. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: complete lingering requests only onceAlex Elder
An osd request marked to linger will be re-submitted in the event a connection to the target osd gets dropped. Currently, if there is a callback function associated with a request it will be called each time a request is submitted--which for lingering requests can be more than once. Change it so a request--including lingering ones--will get completed (from the perspective of the user of the osd client) exactly once. This resolves: http://tracker.ceph.com/issues/3967 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01ceph: acquire i_mutex in __ceph_do_pending_vmtruncateYan, Zheng
make __ceph_do_pending_vmtruncate() acquire the i_mutex if the caller does not hold the i_mutex, so ceph_aio_read() can call safely. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01ceph: don't early drop Fw capYan, Zheng
ceph_aio_write() has an optimization that marks CEPH_CAP_FILE_WR cap dirty before data is copied to page cache and inode size is updated. The optimization avoids slow cap revocation caused by balance_dirty_pages(), but introduces inode size update race. If ceph_check_caps() flushes the dirty cap before the inode size is updated, MDS can miss the new inode size. So just remove the optimization. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01ceph: revert commit 22cddde104Sage Weil
commit 22cddde104 breaks the atomicity of write operation, it also introduces a deadlock between write and truncate. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com> Conflicts: fs/ceph/addr.c
2013-05-01ceph: use I_COMPLETE inode flag instead of D_COMPLETE flagYan, Zheng
commit c6ffe10015 moved the flag that tracks if the dcache contents for a directory are complete to dentry. The problem is there are lots of places that use ceph_dir_{set,clear,test}_complete() while holding i_ceph_lock. but ceph_dir_{set,clear,test}_complete() may sleep because they call dput(). This patch basically reverts that commit. For ceph_d_prune(), it's called with both the dentry to prune and the parent dentry are locked. So it's safe to access the parent dentry's d_inode and clear I_COMPLETE flag. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com> Reviewed-by: Sage Weil <sage@inktank.com>
2013-05-01ceph: set mds_want according to cap import messageYan, Zheng
MDS ignores cap update message if migrate_seq mismatch, so when receiving a cap import message with higher migrate_seq, set mds_want according to the cap import message. Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01ceph: queue cap release when trimming capYan, Zheng
So the client will later send cap release message to MDS Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01ceph: fix LSSNAP regressionYan, Zheng
commit 6e8575faa8 makes parse_reply_info_extra() return -EIO for LSSNAP Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com> Reviewed-by: Greg Farnum <greg@inktank.com>
2013-05-01libceph: set page alignment in start_request()Alex Elder
The page alignment field for a request is currently set in ceph_osdc_build_request(). It's not needed at that point nor do either of its callers need that value assigned at any point before they call ceph_osdc_start_request(). So move that assignment into ceph_osdc_start_request(). Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: distinguish page array and pagelist countAlex Elder
Use distinct fields for tracking the number of pages in a message's page array and in a message's page list. Currently only one or the other is used at a time, but that will be changing soon. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: don't pass request to calc_layout()Alex Elder
The only remaining reason to pass the osd request to calc_layout() is to fill in its r_num_pages and r_page_alignment fields. Once it fills those in, it doesn't do anything more with them. We can therefore move those assignments into the caller, and get rid of the "req" parameter entirely. Note, however, that the only caller is ceph_osdc_new_request(), and that immediately overwrites those fields with values based on its passed-in page offset. So the assignment inside calc_layout() was redundant anyway. This resolves: http://tracker.ceph.com/issues/4262 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: format target object name in callerAlex Elder
Move the formatting of the object name (oid) to use for an object request into the caller of calc_layout(). This makes the "vino" parameter no longer necessary, so get rid of it. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: pass object number back to calc_layout() callerAlex Elder
Have calc_layout() pass the computed object number back to its caller. (This is a small step to simplify review.) Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: make ceph_msg->bio_seg be unsignedAlex Elder
The bio_seg field is used by the ceph messenger in iterating through a bio. It should never have a negative value, so make it an unsigned. (I contemplated making it unsigned short to match the struct bio definition, but it offered no benefit.) Change variables used to hold bio_seg values to all be unsigned as well. Change two variable names in init_bio_iter() to match the convention used everywhere else. Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2013-05-01libceph: fix a osd request memory leakAlex Elder
If an invalid layout is provided to ceph_osdc_new_request(), its call to calc_layout() might return an error. At that point in the function we've already allocated an osd request structure, so we need to free it (drop a reference) in the event such an error occurs. The only other value calc_layout() will return is 0, so make that explicit in the successful case. This resolves: http://tracker.ceph.com/issues/4240 Signed-off-by: Alex Elder <elder@inktank.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com>