Граф коммитов

323382 Коммитов

Автор SHA1 Сообщение Дата
Joe Perches d2cc4dde92 bdi_register: add __printf verification, fix arg mismatch
__printf is useful to verify format and arguments.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-12-13 08:13:07 -06:00
Sage Weil 83aff95eb9 libceph: remove 'osdtimeout' option
This would reset a connection with any OSD that had an outstanding
request that was taking more than N seconds.  The idea was that if the
OSD was buggy, the client could compensate by resending the request.

In reality, this only served to hide server bugs, and we haven't
actually seen such a bug in quite a while.  Moreover, the userspace
client code never did this.

More importantly, often the request is taking a long time because the
OSD is trying to recover, or overloaded, and killing the connection
and retrying would only make the situation worse by giving the OSD
more work to do.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-12-13 08:13:06 -06:00
Cyril Roelandt cfc84c9f73 ceph: fix dentry reference leak in ceph_encode_fh().
dput() was not called in the error path.

Signed-off-by: Cyril Roelandt <tipecaml@gmail.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-12-13 08:13:06 -06:00
Sage Weil 22cddde104 ceph: Fix i_size update race
ceph_aio_write() has an optimization that marks cap EPH_CAP_FILE_WR
dirty before data is copied to page cache and inode size is updated.
If ceph_check_caps() flushes the dirty cap before the inode size is
updated, MDS can miss the new inode size. The fix is move
ceph_{get,put}_cap_refs() into ceph_write_{begin,end}() and call
__ceph_mark_dirty_caps() after inode size is updated.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Sage Weil <sage@inktank.com>
2012-11-05 11:07:23 -08:00
Yan, Zheng 4d1d0534f5 ceph: Hold caps_list_lock when adjusting caps_{use, total}_count
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Sage Weil <sage@inktank.com>
2012-11-04 03:08:24 -08:00
Alex Elder 9e15b77d9a rbd: get additional info in parent spec
When a layered rbd image has a parent, that parent is identified
only by its pool id, image id, and snapshot id.  Images that have
been mapped also record *names* for those three id's.

Add code to look up these names for parent images so they match
mapped images more closely.  Skip doing this for an image if it
already has its pool name defined (this will be the case for images
mapped by the user).

It is possible that an the name of a parent image can't be
determined, even if the image id is valid.  If this occurs it
does not preclude correct operation, so don't treat this as
an error.

On the other hand, defined pools will always have both an id and a
name.   And any snapshot of an image identified as a parent for a
clone image will exist, and will have a name (if not it indicates
some other internal error).  So treat failure to get these bits
of information as errors.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder 72afc71ffc libceph: define ceph_pg_pool_name_by_id()
Define and export function ceph_pg_pool_name_by_id() to supply
the name of a pg pool whose id is given.  This will be used by
the next patch.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder 86b00e0da6 rbd: get parent spec for version 2 images
Add support for getting the the information identifying the parent
image for rbd images that have them.  The child image holds a
reference to its parent image specification structure.  Create a new
entry "parent" in /sys/bus/rbd/image/N/ to report the identifying
information for the parent image, if any.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder a92ffdf8a9 rbd: allow null image name
Format 2 parent images are partially identified by their image id,
but it may not be possible to determine their image name.  The name
is not strictly needed for correct operation, so we won't be
treating it as an error if we don't know it.  Handle this case
gracefully in rbd_name_show().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder 2c0d0a10ea rbd: allow null image name
We will know the image id for format 2 parent images, but won't
initially know its image name.  Avoid making the query for an image
id in rbd_dev_image_id() if it's already known.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder 83a0626362 rbd: encapsulate last part of probe
Group the activities that now take place after an rbd_dev_probe()
call into a single function, and move the call to that function
into rbd_dev_probe() itself.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder c53d589337 rbd: define rbd_dev_{create,destroy}() helpers
Encapsulate the creation/initialization and destruction of rbd
device structures.  The rbd_client and the rbd_spec structures
provided on creation hold references whose ownership is transferred
to the new rbd_device structure.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder bd4ba6554d rbd: consolidate rbd_dev init in rbd_add()
Group the allocation and initialization of fields of the rbd device
structure created in rbd_add().  Move the grouped code down later in
the function, just prior to the call to rbd_dev_probe().  This is
for the most part simple code movement.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder 9d3997fdf4 rbd: don't pass rbd_dev to rbd_get_client()
The only reason rbd_dev is passed to rbd_get_client() is so its
rbd_client field can get assigned.  Instead, just return the
rbd_client pointer as a result and have the caller do the
assignment.

Change rbd_put_client() so it takes an rbd_client structure,
so follows the more typical symmetry with rbd_get_client().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder 859c31df9c rbd: fill rbd_spec in rbd_add_parse_args()
Pass the address of an rbd_spec structure to rbd_add_parse_args().
Use it to hold the information defining the rbd image to be mapped
in an rbd_add() call.

Use the result in the caller to initialize the rbd_dev->id field.

This means rbd_dev is no longer needed in rbd_add_parse_args(),
so get rid of it.

Now that this transformation of rbd_add_parse_args() is complete,
correct and expand on the its header documentation to reflect the
new reality.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:42 -05:00
Alex Elder 8b8fb99c5c rbd: add reference counting to rbd_spec
With layered images we'll share rbd_spec structures, so add a
reference count to it.  It neatens up some code also.

A silly get/put pair is added to the alloc routine just to avoid
"defined but not used" warnings.  It will go away soon.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-11-01 07:55:41 -05:00
Alex Elder 0d7dbfce9d rbd: define image specification structure
Group the fields that uniquely specify an rbd image into a new
reference-counted rbd_spec structure.  This structure will be used
to describe the desired image when mapping an image, and when
probing parent images in layered rbd devices.  Replace the set of
fields in the rbd device structure with a pointer to a dynamically
allocated rbd_spec.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:30 -05:00
Alex Elder dc79b113d6 rbd: have rbd_add_parse_args() return error
Change the interface to rbd_add_parse_args() so it returns an
error code rather than a pointer.  Return the ceph_options result
via a pointer whose address is passed as an argument.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:30 -05:00
Alex Elder 4e9afeba7a rbd: pass and populate rbd_options structure
Have the caller pass the address of an rbd_options structure to
rbd_add_parse_args(), to be initialized with the information
gleaned as a result of the parse.

I know, this is another near-reversal of a recent change...

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder 819d52bf72 rbd: remove snap_name arg from rbd_add_parse_args()
The snapshot name returned by rbd_add_parse_args() just gets saved
in the rbd_dev eventually.  So just do that inside that function and
do away with the snap_name argument, both in rbd_add_parse_args()
and rbd_dev_set_mapping().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder f28e565a1b rbd: remove options args from rbd_add_parse_args()
They "options" argument to rbd_add_parse_args() (and it's partner
options_size) is now only needed within the function, so there's no
need to have the caller allocate and pass the options buffer.  Just
allocate the options buffer within the function using dup_token().

Also distinguish between failures due to failed memory allocation
and failing because a required argument was missing.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder e5c3553404 rbd: get rid of snap_name_len
The value returned in the "snap_name_len" argument to
rbd_add_parse_args() is never actually used, so get rid of it.

The snap_name_len recorded in rbd_dev_v2_snap_name() is not
useful either, so get rid of that too.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder 0ddebc0c6c rbd: do all argument parsing in one place
This patch makes rbd_add_parse_args() be the single place all
argument parsing occurs for an image map request:
    - Move the ceph_parse_options() call into that function
    - Use local variables rather than parameters to hold the list
      of monitor addresses supplied
    - Rather than returning it, pass the snapshot name (and its
      length) back via parameters
    - Have the function return a ceph_options structure pointer

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder 78cea76e05 rbd: move ceph_parse_options() call up
Move option parsing out of rbd_get_client() and into its caller.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder daba5fdb4c rbd: rename snap_exists field
A Boolean field "snap_exists" in an rbd mapping is used to indicate
whether a mapped snapshot has been removed from an image's snapshot
context, to stop sending requests for that snapshot as soon as we
know it's gone.

Generalize the interpretation of this field so it applies to
non-snapshot (i.e. "head") mappings.  That is, define its value
to be false until the mapping has been set, and then define it to be
true for both snapshot mappings or head mappings.

Rename the field "exists" to reflect the broader interpretation.
The rbd_mapping structure is on its way out, so move the field
back into the rbd_device structure.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder 971f839a76 rbd: move snap info out of rbd_mapping struct
Moving the snap_id and snap_name fields into the separate
rbd_mapping structure was misguided.  (And in time, perhaps
we'll do away with that structure altogether...)

Move these fields back into struct rbd_device.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder 86992098e7 rbd: make pool_id a 64 bit value
If a format 2 image has a parent, its pool id will be specified
using a 64-bit value.  Change the pool id we save for an image to
match that.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:29 -05:00
Alex Elder 41f38c2b2f rbd: remove snapshots on error in rbd_add()
If rbd_dev_snaps_update() has ever been called for an rbd device
structure there could be snapshot structures on its snaps list.
In rbd_add(), this function is called but a subsequent error
path neglected to clean up any of these snapshots.

Add a call to rbd_remove_all_snaps() in the appropriate spot to
remedy this.  Change a couple of error labels to be a little
clearer while there.

Drop the leading underscores from the function name; there's nothing
special about that function that they might signify.  As suggested
in review, the leading underscores in __rbd_remove_snap_dev() have
been removed as well.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:28 -05:00
Alex Elder f7760dad28 rbd: simplify rbd_rq_fn()
When processing a request, rbd_rq_fn() makes clones of the bio's in
the request's bio chain and submits the results to osd's to be
satisfied.  If a request bio straddles the boundary between objects
backing the rbd image, it must be represented by two cloned bio's,
one for the first part (at the end of one object) and one for the
second (at the beginning of the next object).

This has been handled by a function bio_chain_clone(), which
includes an interface only a mother could love, and which has
been found to have other problems.

This patch defines two new fairly generic bio functions (one which
replaces bio_chain_clone()) to help out the situation, and then
revises rbd_rq_fn() to make use of them.

First, bio_clone_range() clones a portion of a single bio, starting
at a given offset within the bio and including only as many bytes
as requested.  As a convenience, a request to clone the entire bio
is passed directly to bio_clone().

Second, bio_chain_clone_range() performs a similar function,
producing a chain of cloned bio's covering a sub-range of the
source chain.  No bio_pair structures are used, and if successful
the result will represent exactly the specified range.

Using bio_chain_clone_range() makes bio_rq_fn() a little easier
to understand, because it avoids the need to pass very much
state information between consecutive calls.  By avoiding the need
to track a bio_pair structure, it also eliminates the problem
described here:  http://tracker.newdream.net/issues/2933

Note that a block request (and therefore the complete length of
a bio chain processed in rbd_rq_fn()) is an unsigned int, while
the result of rbd_segment_length() is u64.  This change makes
this range trunctation explicit, and trips a bug if the the
segment boundary is too far off.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-30 08:34:28 -05:00
Sage Weil 0ed7285e00 libceph: fix osdmap decode error paths
Ensure that we set the err value correctly so that we do not pass a 0
value to ERR_PTR and confuse the calling code.  (In particular,
osd_client.c handle_map() will BUG(!newmap)).

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-10-30 08:21:05 -05:00
Alex Elder 069a4b5690 rbd: kill rbd_device->rbd_opts
The rbd_device structure has an embedded rbd_options structure.
Such a structure is needed to work with the generic ceph argument
parsing code, but there's no need to keep it around once argument
parsing is done.

Use a local variable to hold the rbd options used in parsing in
rbd_get_client(), and just transfer its content (it's just a
read_only flag) into the field in the rbd_mapping sub-structure
that requires that information.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder e5cfeed281 rbd: simplify rbd_merge_bvec()
The aim of this patch is to make what's going on rbd_merge_bvec() a
bit more obvious than it was before.  This was an issue when a
recent btrfs bug led us to question whether the merge function was
working correctly.

Use "obj" rather than "chunk" to indicate the units whose boundaries
we care about we call (rados) "objects".

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder d4b125e9eb rbd: increase maximum snapshot name length
Change RBD_MAX_SNAP_NAME_LEN to be based on NAME_MAX.  That is a
practical limit for the length of a snapshot name (based on the
presence of a directory using the name under /sys/bus/rbd to
represent the snapshot).

The /sys entry is created by prefixing it with "snap_"; define that
prefix symbolically, and take its length into account in defining
the snapshot name length limit.

Enforce the limit in rbd_add_parse_args().  Also delete a dout()
call in that function that was not meant to be committed.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder db2388b6ee rbd: verify rbd image order value
This adds a verification that an rbd image's object order is
within the upper and lower bounds supported by this implementation.

It must be at least 9 (SECTOR_SHIFT), because the Linux bio system
assumes that minimum granularity.

It also must be less than 32 (at the moment anyway) because there
exist spots in the code that store the size of a "segment" (object
backing an rbd image) in a signed int variable, which can be 32 bits
including the sign.  We should be able to relax this limit once
we've verified the code uses 64-bit types where needed.

Note that the CLI tool already limits the order to the range 12-25.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder 4634246db8 rbd: consolidate rbd_do_op() calls
The two calls to rbd_do_op() from rbd_rq_fn() differ only in the
value passed for the snapshot id and the snapshot context.

For reads the snapshot always comes from the mapping, and for writes
the snapshot id is always CEPH_NOSNAP.

The snapshot context is always null for reads.  For writes, the
snapshot context always comes from the rbd header, but it is
acquired under protection of header semaphore and could change
thereafter, so we can't simply use what's available inside
rbd_do_op().

Eliminate the snapid parameter from rbd_do_op(), and set it
based on the I/O direction inside that function instead.  Always
pass the snapshot context acquired in the caller, but reset it
to a null pointer inside rbd_do_op() if the operation is a read.

As a result, there is no difference in the read and write calls
to rbd_do_op() made in rbd_rq_fn(), so just call it unconditionally.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder ff2e4bb5b3 rbd: drop rbd_do_op() opcode and flags
The only callers of rbd_do_op() are in rbd_rq_fn(), where call one
is used for writes and the other used for reads.  The request passed
to rbd_do_op() already encodes the I/O direction, and that
information can be used inside the function to set the opcode and
flags value (rather than passing them in as arguments).

So get rid of the opcode and flags arguments to rbd_do_op().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder 13f4042c05 rbd: kill rbd_req_{read,write}()
Both rbd_req_read() and rbd_req_write() are simple wrapper routines
for rbd_do_op(), and each is only called once.  Replace each wrapper
call with a direct call to rbd_do_op(), and get rid of the wrapper
functions.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder be466c1cc3 rbd: fix read-only option name
The name of the "read-only" mapping option was inadvertently changed
in this commit:

    f84344f3 rbd: separate mapping info in rbd_dev

Revert that hunk to return it to what it should be.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder a0ea3a40fd rbd: zero return code in rbd_dev_image_id()
When rbd_dev_probe() calls rbd_dev_image_id() it expects to get
a 0 return code if successful, but it is getting a positive value.

The reason is that rbd_dev_image_id() returns the value it gets from
rbd_req_sync_exec(), which returns the number of bytes read in as a
result of the request.  (This ultimately comes from
ceph_copy_from_page_vector() in rbd_req_sync_op()).

Force the return value to 0 when successful in rbd_dev_image_id().
Do the same in rbd_dev_v2_object_prefix().

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
2012-10-26 17:18:08 -05:00
Alex Elder b213e0b1a6 rbd: fix bug in rbd_dev_id_put()
In rbd_dev_id_put(), there's a loop that's intended to determine
the maximum device id in use.  But it isn't doing that at all,
the effect of how it's written is to simply use the just-put id
number, which ignores whole purpose of this function.

Fix the bug.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-26 17:18:08 -05:00
David Zafman b000056a5a ceph: Fix NULL ptr crash in strlen()
set_request_path_attr() checks for NULL ptr before calling strlen()

This fixes http://tracker.newdream.net/issues/3404

Signed-off-by: David Zafman <david.zafman@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-10-26 16:35:07 -05:00
Sage Weil 7246240c7c libceph: avoid NULL kref_put from NULL alloc_msg return
The ceph_on_in_msg_alloc() method calls the ->alloc_msg() helper which
may return NULL.  It also drops con->mutex while it allocates a message,
which means that the connection state may change (e.g., get closed).  If
that happens, we clean up and bail out.  Avoid calling ceph_msg_put() on
a NULL return value and triggering a crash.

This was observed when an ->alloc_msg() call races with a timeout that
resends a zillion messages and resets the connection, and ->alloc_msg()
returns NULL (because the request was resent to another target).

Fixes http://tracker.newdream.net/issues/3342

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
2012-10-26 16:35:04 -05:00
David Zafman 0f9831a893 ceph: fix dentry reference leak in encode_fh()
Call to d_find_alias() needs a corresponding dput()

This fixes http://tracker.newdream.net/issues/3271

Signed-off-by: David Zafman <david.zafman@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-10-26 16:34:53 -05:00
Alex Elder 35152979e6 rbd: activate v2 image support
Now that v2 images support is fully implemented, have
rbd_dev_v2_probe() return 0 to indicate a successful probe.

(Note that an image that implements layering will fail
the probe early because of the feature chekc.)

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-10 07:44:01 -07:00
Alex Elder d889140c4a rbd: implement feature checks
Version 2 images have two sets of feature bit fields.  The first
indicates features possibly used by the image.  The second indicates
features that the client *must* support in order to use the image.

When an image (or snapshot) is first examined, we need to make sure
that the local implementation supports the image's required
features.  If not, fail the probe for the image.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-10 07:43:51 -07:00
Alex Elder 117973fb4c rbd: define rbd_dev_v2_refresh()
Define a new function rbd_dev_v2_refresh() to update/refresh the
snapshot context for a format version 2 rbd image.  This function
will update anything that is not fixed for the life of an rbd
image--at the moment this is mainly the snapshot context and (for
a base mapping) the size.

Update rbd_refresh_header() so it selects which function to use
based on the image format.

Rename __rbd_refresh_header() to be rbd_dev_v1_refresh()
to be consistent with the naming of its version 2 counterpart.
Similarly rename rbd_refresh_header() to be rbd_dev_refresh().

Unrelated--we use rbd_image_format_valid() here.  Delete the other
use of it, which was primarily put in place to ensure that function
was referenced at the time it was defined.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-10 07:43:39 -07:00
Alex Elder 9478554ae5 rbd: define rbd_update_mapping_size()
Encapsulate the code that handles updating the size of a mapping
after an rbd image has been refreshed.  This is done in anticipation
of the next patch, which will make this common code for format 1 and
2 images.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
2012-10-10 07:43:28 -07:00
Alex Elder 802c6d967f rbd: define common queue_con_delay()
This patch defines a single function, queue_con_delay() to call
queue_delayed_work() for a connection.  It basically generalizes
what was previously queue_con() by adding the delay argument.
queue_con() is now a simple helper that passes 0 for its delay.
queue_con_delay() returns 0 if it queued work or an errno if it
did not for some reason.

If con_work() finds the BACKOFF flag set for a connection, it now
calls queue_con_delay() to handle arranging to start again after a
delay.

Note about connection reference counts:  con_work() only ever gets
called as a work item function.  At the time that work is scheduled,
a reference to the connection is acquired, and the corresponding
con_work() call is then responsible for dropping that reference
before it returns.

Previously, the backoff handling inside con_work() silently handed
off its reference to delayed work it scheduled.  Now that
queue_con_delay() is used, a new reference is acquired for the
newly-scheduled work, and the original reference is dropped by the
con->ops->put() call at the end of the function.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-10-09 22:00:44 -07:00
Alex Elder 8618e30bc1 rbd: let con_work() handle backoff
Both ceph_fault() and con_work() include handling for imposing a
delay before doing further processing on a faulted connection.
The latter is used only if ceph_fault() is unable to.

Instead, just let con_work() always be responsible for implementing
the delay.  After setting up the delay value, set the BACKOFF flag
on the connection unconditionally and call queue_con() to ensure
con_work() will get called to handle it.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-10-09 22:00:21 -07:00
Alex Elder 588377d619 rbd: reset BACKOFF if unable to re-queue
If ceph_fault() is unable to queue work after a delay, it sets the
BACKOFF connection flag so con_work() will attempt to do so.

In con_work(), when BACKOFF is set, if queue_delayed_work() doesn't
result in newly-queued work, it simply ignores this condition and
proceeds as if no backoff delay were desired.  There are two
problems with this--one of which is a bug.

The first problem is simply that the intended behavior is to back
off, and if we aren't able queue the work item to run after a delay
we're not doing that.

The only reason queue_delayed_work() won't queue work is if the
provided work item is already queued.  In the messenger, this
means that con_work() is already scheduled to be run again.  So
if we simply set the BACKOFF flag again when this occurs, we know
the next con_work() call will again attempt to hold off activity
on the connection until after the delay.

The second problem--the bug--is a leak of a reference count.  If
queue_delayed_work() returns 0 in con_work(), con->ops->put() drops
the connection reference held on entry to con_work().  However,
processing is (was) allowed to continue, and at the end of the
function a second con->ops->put() is called.

This patch fixes both problems.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>
2012-10-09 21:59:52 -07:00