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>
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>
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>
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>
It's possible that the reference to the object request dropped
inside the loop in rbd_img_request_submit() will be the last
one, in which case the content of the object pointer can't be
trusted.
Use a safe form of the object request list traversal to avoid
problems.
This resolves:
http://tracker.ceph.com/issues/4705
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Tejun writes:
-----
This is the pull request for the earlier patchset[1] with the same
name. It's only three patches (the first one was committed to
workqueue tree) but the merge strategy is a bit involved due to the
dependencies.
* Because the conversion needs features from wq/for-3.10,
block/for-3.10/core is based on rc3, and wq/for-3.10 has conflicts
with rc3, I pulled mainline (rc5) into wq/for-3.10 to prevent those
workqueue conflicts from flaring up in block tree.
* Resolving the issue that Jan and Dave raised about debugging
requires arch-wide changes. The patchset is being worked on[2] but
it'll have to go through -mm after these changes show up in -next,
and not included in this pull request.
The three commits are located in the following git branch.
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git writeback-workqueue
Pulling it into block/for-3.10/core produces a conflict in
drivers/md/raid5.c between the following two commits.
e3620a3ad5 ("MD RAID5: Avoid accessing gendisk or queue structs when not available")
2f6db2a707 ("raid5: use bio_reset()")
The conflict is trivial - one removes an "if ()" conditional while the
other removes "rbi->bi_next = NULL" right above it. We just need to
remove both. The merged branch is available at
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git block-test-merge
so that you can use it for verification. The test merge commit has
proper merge description.
While these changes are a bit of pain to route, they make code simpler
and even have, while minute, measureable performance gain[3] even on a
workload which isn't particularly favorable to showing the benefits of
this conversion.
----
Fixed up the conflict.
Conflicts:
drivers/md/raid5.c
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A result of ENOENT from a read request for an object that's part of
an rbd image indicates that there is a hole in that portion of the
image. Similarly, a short read for such an object indicates that
the remainder of the read should be interpreted a full read with
zeros filling out the end of the request.
This behavior is not correct for objects that are not backing rbd
image data. Currently rbd_img_obj_request_callback() assumes it
should be done for all objects.
Change rbd_img_obj_request_callback() so it only does this zeroing
for image objects. Encapsulate that special handling in its own
function. Add an assertion that the image object request is a bio
request, since we assume that (and we currently don't support any
other types).
This resolves a problem identified here:
http://tracker.ceph.com/issues/4559
The regression was introduced by bf0d5f503d.
Reported-by: Dan van der Ster <dan@vanderster.com>
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-off-by: Sage Weil <sage@inktank.com>
__bio_for_each_segment() iterates bvecs from the specified index
instead of bio->bv_idx. Currently, the only usage is to walk all the
bvecs after the bio has been advanced by specifying 0 index.
For immutable bvecs, we need to split these apart;
bio_for_each_segment() is going to have a different implementation.
This will also help document the intent of code that's using it -
bio_for_each_segment_all() is only legal to use for code that owns the
bio.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Neil Brown <neilb@suse.de>
CC: Boaz Harrosh <bharrosh@panasas.com>
Use the new version of the encoding for osd requests and replies. In the
process, update the way we are tracking request ops and reply lengths and
results in the struct ceph_osd_request. Update the rbd and fs/ceph users
appropriately.
The main changes are:
- we keep pointers into the request memory for fields we need to update
each time the request is sent out over the wire
- we keep information about the result in an array in the request struct
where the users can easily get at it.
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
The only thing type-specific osd completion functions do with their
osd op parameter is (in some cases) extract the number of bytes
transferred from it. In the other cases, the xferred bytes field
is not used, and total message data transfer byte count (which may
well be zero) is used.
Just set the object request transfer count in the main osd request
callback function and provide that to the other routines. There is
then no longer any need to pass the op pointer to the type-specific
completion routines, so drop those parameters.
Stop doing anything with the total message data length.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
This function is slightly out of place, probably the result
of an errant automatic merge or something.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Fengguang Wu reminded me that there were outstanding sparse reports
in the ceph and rbd code. This patch fixes these problems in rbd
that lead to those reports:
- Convert functions that are never referenced externally to have
static scope.
- Add a lockdep annotation to rbd_request_fn(), because it
releases a lock before acquiring it again.
This partially resolves:
http://tracker.ceph.com/issues/4184
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Add dout() calls to facilitate tracing of image and object requests.
Change a few existing calls so they use __func__ rather than the
hard-coded function name. Have calls always add ":" after the name
of the function, and prefix pointer values with a consistent tag
indicating what it represents. (Note that there remain some older
dout() calls that are left untouched by this patch.)
Issue a warning if rbd_osd_write_callback() ever gets a short write.
This resolves:
http://tracker.ceph.com/issues/4235
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Let's go shopping!
I'm afraid this may not have gotten it right:
07741308 rbd: add barriers near done flag operations
The smp_wmb() should have been done *before* setting the done flag,
to ensure all other data was valid before marking the object request
done.
Switch to use atomic_inc_return() here to set the done flag, which
allows us to verify we don't mark something done more than once.
Doing this also implies general barriers before and after the call.
And although a read memory barrier might have been sufficient before
reading the done flag, convert this to a full memory barrier just
to put this issue to bed.
This resolves:
http://tracker.ceph.com/issues/4238
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The old request code simply ignored zero-length requests. We should
still operate that same way to avoid any changes in behavior. We
can implement handling for special zero-length requests separately
(see http://tracker.ceph.com/issues/4236).
Add some assertions based on this new constraint.
This resolves:
http://tracker.ceph.com/issues/4237
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The return values provided for ceph_copy_to_page_vector() and
ceph_copy_from_page_vector() serve no purpose, so get rid of them.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The result of ceph_copy_from_page_vector() is simply the length
argument it is provided.
This is called by rbd_obj_method_sync(), which returns the result if
it's non-negative. But we always either ignore or overwrite that
return value. So explicitly ignore what's returned by the copy
function, and have rbd_obj_method_sync() always return either a
negative errno or 0.
We also return the result of ceph_copy_from_page_vector() in
rbd_obj_read_sync(). There we still want to return the number of
bytes transferred, but we can use the value we already have in hand
rather than what ceph_copy_from_page_vector() provides.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
In rbd_obj_read_sync(), verify the number of bytes transferred won't
exceed what can be represented by a size_t before using it to
indicate the number of bytes to copy to the result buffer.
(The real motivation for this is to prepare for the next patch.)
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Add support for CEPH_OSD_OP_STAT operations in the osd client
and in rbd.
This operation sends no data to the osd; everything required is
encoded in identity of the target object.
The result will be ENOENT if the object doesn't exist. If it does
exist and no other error occurs the server returns the size and last
modification time of the target object as output data (in little
endian format). The size is a 64 bit unsigned and the time is
ceph_timespec structure (two unsigned 32-bit integers, representing
a seconds and nanoseconds value).
This resolves:
http://tracker.ceph.com/issues/4007
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The for_each_obj_request*() macros should parenthesize their uses of
the ireq parameter.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
There is only one caller of ceph_osdc_create_event(), and it
provides 0 as its "one_shot" argument. Get rid of that argument and
just use 0 in its place.
Replace the code in handle_watch_notify() that executes if one_shot
is nonzero in the event with a BUG_ON() call.
While modifying "osd_client.c", give handle_watch_notify() static
scope.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Somehow, I missed this little item in Documentation/atomic_ops.txt:
*** WARNING: atomic_read() and atomic_set() DO NOT IMPLY BARRIERS! ***
Create and use some helper functions that include the proper memory
barriers for manipulating the done field.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
This commit:
bc7a62ee5 rbd: prevent open for image being removed
added checking for removing rbd before allowing an open, and used
the same request spinlock for protecting that and updating the open
count as is used for the request queue.
However it used the non-irq protected version of the spinlocks.
Fix that.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
There is a check in the completion path for osd requests that
ensures the number of pages allocated is enough to hold the amount
of incoming data expected.
For bio requests coming from rbd the "number of pages" is not really
meaningful (although total length would be). So stop requiring that
nr_pages be supplied for bio requests. This is done by checking
whether the pages pointer is null before checking the value of
nr_pages.
Note that this value is passed on to the messenger, but there it's
only used for debugging--it's never used for validation.
While here, change another spot that used r_pages in a debug message
inappropriately, and also invalidate the r_con_filling_msg pointer
after dropping a reference to it.
This resolves:
http://tracker.ceph.com/issues/3875
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Currently, if the OSD client finds an osd request has had a bio list
attached to it, it drops a reference to it (or rather, to the first
entry on that list) when the request is released.
The code that added that reference (i.e., the rbd client) is
therefore required to take an extra reference to that first bio
structure.
The osd client doesn't really do anything with the bio pointer other
than transfer it from the osd request structure to outgoing (for
writes) and ingoing (for reads) messages. So it really isn't the
right place to be taking or dropping references.
Furthermore, the rbd client already holds references to all bio
structures it passes to the osd client, and holds them until the
request is completed. So there's no need for this extra reference
whatsoever.
So remove the bio_put() call in ceph_osdc_release_request(), as
well as its matching bio_get() call in rbd_osd_req_create().
This change could lead to a crash if old libceph.ko was used with
new rbd.ko. Add a compatibility check at rbd initialization time to
avoid this possibilty.
This resolves:
http://tracker.ceph.com/issues/3798 and
http://tracker.ceph.com/issues/3799
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
An open request for a mapped rbd image can arrive while removal of
that mapping is underway. We need to prevent such an open request
from succeeding. (It appears that Maciej Galkiewicz ran into this
problem.)
Define and use a "removing" flag to indicate a mapping is getting
removed. Set it in the remove path after verifying nothing holds
the device open. And check it in the open path before allowing the
open to proceed. Acquire the rbd device's lock around each of these
spots to avoid any races accessing the flags and open_count fields.
This addresses:
http://tracker.newdream.net/issues/3427
Reported-by: Maciej Galkiewicz <maciejgalkiewicz@ragnarson.com>
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Define a new rbd device flags field, manipulated using bit
operations. Replace the use of the current "exists" flag with a bit
in this new "flags" field. Add a little commentary about the
"exists" flag, which does not need to be manipulated atomically.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
When we register an osd request to linger, it means that request
will stay around (under control of the osd client) until we've
unregistered it. We do that for an rbd image's header object, and
we keep a pointer to the object request associated with it.
Keep a reference to the watch object request for as long as it is
registered to linger. Drop it again after we've removed the linger
registration.
This resolves:
http://tracker.ceph.com/issues/3937
(Note: this originally came about because the osd client was
issuing a callback more than once. But that behavior will be
changing soon, documented in tracker issue 3967.)
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Switch to keeping track of the object request pointer rather than
the osd request used to watch the rbd image header object.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Move the code that unregisters an rbd device's lingering header
object watch request into rbd_dev_header_watch_sync(), so it
occurs in the same function that originally sets up that request.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Get rid rbd_req_sync_exec() because it is no longer used. That
eliminates the last use of rbd_req_sync_op(), so get rid of that
too. And finally, that leaves rbd_do_request() unreferenced, so get
rid of that.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Reimplement synchronous object method calls using the new request
tracking code. Use the name rbd_obj_method_sync()
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
When we receive notification of a change to an rbd image's header
object we need to refresh our information about the image (its
size and snapshot context). Once we have refreshed our rbd image
we need to acknowledge the notification.
This acknowledgement was previously done synchronously, but there's
really no need to wait for it to complete.
Change it so the caller doesn't wait for the notify acknowledgement
request to complete. And change the name to reflect it's no longer
synchronous.
This resolves:
http://tracker.newdream.net/issues/3877
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Get rid rbd_req_sync_notify_ack() because it is no longer used.
As a result rbd_simple_req_cb() becomes unreferenced, so get rid
of that too.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Use the new object request tracking mechanism for handling a
notify_ack request.
Move the callback function below the definition of this so we don't
have to do a pre-declaration.
This resolves:
http://tracker.newdream.net/issues/3754
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Implement a new function to set up or tear down a watch event
for an mapped rbd image header using the new request code.
Create a new object request type "nodata" to handle this. And
define rbd_osd_trivial_callback() which simply marks a request done.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Delete rbd_req_sync_read() is no longer used, so get rid of it.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Reimplement the synchronous read operation used for reading a
version 1 header using the new request tracking code. Name the
resulting function rbd_obj_read_sync() to better reflect that
it's a full object operation, not an object request. To do this,
implement a new OBJ_REQUEST_PAGES object request type.
This implements a new mechanism to allow the caller to wait for
completion for an rbd_obj_request by calling rbd_obj_request_wait().
This partially resolves:
http://tracker.newdream.net/issues/3755
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The two remaining callers of rbd_do_request() always pass a null
collection pointer, so the "coll" and "coll_index" parameters are
not needed. There is no other use of that data structure, so it
can be eliminated.
Deleting them means there is no need to allocate a rbd_request
structure for the callback function. And since that's the only use
of *that* structure, it too can be eliminated.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Now that the request function has been replaced by one using the new
request management data structures the old one can go away.
Deleting it makes rbd_dev_do_request() no longer needed, and
deleting that makes other functions unneeded, and so on.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
This patch fully implements the new request tracking code for rbd
I/O requests.
Each I/O request to an rbd image will get an rbd_image_request
structure allocated to track it. This provides access to all
information about the original request, as well as access to the
set of one or more object requests that are initiated as a result
of the image request.
An rbd_obj_request structure defines a request sent to a single osd
object (possibly) as part of an rbd image request. An rbd object
request refers to a ceph_osd_request structure built up to represent
the request; for now it will contain a single osd operation. It
also provides space to hold the result status and the version of the
object when the osd request completes.
An rbd_obj_request structure can also stand on its own. This will
be used for reading the version 1 header object, for issuing
acknowledgements to event notifications, and for making object
method calls.
All rbd object requests now complete asynchronously with respect
to the osd client--they supply a common callback routine.
This resolves:
http://tracker.newdream.net/issues/3741
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
When an rbd image is initially mapped a watch event is registered so
we can do something if the header object changes.
The code that does this currently loops if initiating the watch
request results in an ERANGE error. The osds will never return
ERANGE, so there's no reason to do this loop, so get rid of it.
This resolves:
http://tracker.newdream.net/issues/3860
Note that the problem this loop was intended to solve is a race
between collecting image header information and setting up the watch
on the header object. The real fix for that problem is described
here:
http://tracker.newdream.net/issues/3871
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The return type of rbd_get_num_segments() is int, but the values it
operates on are u64. Although it's not likely, there's no guarantee
the result won't exceed what can be respresented in an int. The
function is already designed to return -ERANGE on error, so just add
this possible overflow as another reason to return that.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
A few very minor changes to the rbd code:
- RBD_MAX_OPT_LEN is unused, so get rid of it
- Consolidate rbd options definitions
- Make rbd_segment_name() return pointer to const char
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The type of the snap_id local variable is defined with the
wrong byte order. Fix that.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Both rbd_req_sync_op() and rbd_do_request() have a "linger"
parameter, which is the address of a pointer that should refer to
the osd request structure used to issue a request to an osd.
Only one case ever supplies a non-null "linger" argument: an
CEPH_OSD_OP_WATCH start. And in that one case it is assigned
&rbd_dev->watch_request.
Within rbd_do_request() (where the assignment ultimately gets made)
we know the rbd_dev and therefore its watch_request field. We
also know whether the op being sent is CEPH_OSD_OP_WATCH start.
Stop opaquely passing down the "linger" pointer, and instead just
assign the value directly inside rbd_do_request() when it's needed.
This makes it unnecessary for rbd_req_sync_watch() to make
arrangements to hold a value that's not available until a
bit later. This more clearly separates setting up a watch
request from submitting it.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
The two remaining osd ops used by rbd are CEPH_OSD_OP_WATCH and
CEPH_OSD_OP_NOTIFY_ACK. Move the setup of those operations into
rbd_osd_req_op_create(), and get rid of rbd_create_rw_op() and
rbd_destroy_op().
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Move the initialization of the CEPH_OSD_OP_CALL operation into
rbd_osd_req_op_create().
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
