The alignment used for reading data into or out of pages used to be taken
from the data_off field in the message header. This only worked as long
as the page alignment matched the object offset, breaking direct io to
non-page aligned offsets.
Instead, explicitly specify the page alignment next to the page vector
in the ceph_msg struct, and use that instead of the message header (which
probably shouldn't be trusted). The alloc_msg callback is responsible for
filling in this field properly when it sets up the page vector.
Signed-off-by: Sage Weil <sage@newdream.net>
We used to infer alignment of IOs within a page based on the file offset,
which assumed they matched. This broke with direct IO that was not aligned
to pages (e.g., 512-byte aligned IO). We were also trusting the alignment
specified in the OSD reply, which could have been adjusted by the server.
Explicitly specify the page alignment when setting up OSD IO requests.
Signed-off-by: Sage Weil <sage@newdream.net>
If the client gets out of sync with the server message sequence number, we
normally skip low seq messages (ones we already received). The skip code
was also incrementing the expected seq, such that all subsequent messages
also appeared old and got skipped, and an eventual timeout on the osd
connection. This resulted in some lagging requests and console messages
like
[233480.882885] ceph: skipping osd22 10.138.138.13:6804 seq 2016, expected 2017
[233480.882919] ceph: skipping osd22 10.138.138.13:6804 seq 2017, expected 2018
[233480.882963] ceph: skipping osd22 10.138.138.13:6804 seq 2018, expected 2019
[233480.883488] ceph: skipping osd22 10.138.138.13:6804 seq 2019, expected 2020
[233485.219558] ceph: skipping osd22 10.138.138.13:6804 seq 2020, expected 2021
[233485.906595] ceph: skipping osd22 10.138.138.13:6804 seq 2021, expected 2022
[233490.379536] ceph: skipping osd22 10.138.138.13:6804 seq 2022, expected 2023
[233495.523260] ceph: skipping osd22 10.138.138.13:6804 seq 2023, expected 2024
[233495.923194] ceph: skipping osd22 10.138.138.13:6804 seq 2024, expected 2025
[233500.534614] ceph: tid 6023602 timed out on osd22, will reset osd
Reported-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sage Weil <sage@newdream.net>
This only happened when parse_extra_token was not passed
to ceph_parse_option() (hence, only happened in rbd).
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
These facilitate preallocation of pages so that we can encode into the pagelist
in an atomic context.
Signed-off-by: Greg Farnum <gregf@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
The rados block device (rbd), based on osdblk, creates a block device
that is backed by objects stored in the Ceph distributed object storage
cluster. Each device consists of a single metadata object and data
striped over many data objects.
The rbd driver supports read-only snapshots.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
This factors out protocol and low-level storage parts of ceph into a
separate libceph module living in net/ceph and include/linux/ceph. This
is mostly a matter of moving files around. However, a few key pieces
of the interface change as well:
- ceph_client becomes ceph_fs_client and ceph_client, where the latter
captures the mon and osd clients, and the fs_client gets the mds client
and file system specific pieces.
- Mount option parsing and debugfs setup is correspondingly broken into
two pieces.
- The mon client gets a generic handler callback for otherwise unknown
messages (mds map, in this case).
- The basic supported/required feature bits can be expanded (and are by
ceph_fs_client).
No functional change, aside from some subtle error handling cases that got
cleaned up in the refactoring process.
Signed-off-by: Sage Weil <sage@newdream.net>
Sage Weil