Commit Graph

7 Commits

Author SHA1 Message Date
Christoph Hellwig
1eb9cd1500 libceph: use bvec_set_page to initialize bvecs
Use the bvec_set_page helper to initialize bvecs.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Link: https://lore.kernel.org/r/20230203150634.3199647-24-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03 10:17:43 -07:00
Al Viro
de4eda9de2 use less confusing names for iov_iter direction initializers
READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.

Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-11-25 13:01:55 -05:00
Jeff Layton
da4ab869e3 libceph: drop last_piece flag from ceph_msg_data_cursor
ceph_msg_data_next is always passed a NULL pointer for this field. Some
of the "next" operations look at it in order to determine the length,
but we can just take the min of the data on the page or cursor->resid.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2022-10-04 19:18:08 +02:00
Ilya Dryomov
038b8d1d1a libceph: optionally use bounce buffer on recv path in crc mode
Both msgr1 and msgr2 in crc mode are zero copy in the sense that
message data is read from the socket directly into the destination
buffer.  We assume that the destination buffer is stable (i.e. remains
unchanged while it is being read to) though.  Otherwise, CRC errors
ensue:

  libceph: read_partial_message 0000000048edf8ad data crc 1063286393 != exp. 228122706
  libceph: osd1 (1)192.168.122.1:6843 bad crc/signature

  libceph: bad data crc, calculated 57958023, expected 1805382778
  libceph: osd2 (2)192.168.122.1:6876 integrity error, bad crc

Introduce rxbounce option to enable use of a bounce buffer when
receiving message data.  In particular this is needed if a mapped
image is a Windows VM disk, passed to QEMU.  Windows has a system-wide
"dummy" page that may be mapped into the destination buffer (potentially
more than once into the same buffer) by the Windows Memory Manager in
an effort to generate a single large I/O [1][2].  QEMU makes a point of
preserving overlap relationships when cloning I/O vectors, so krbd gets
exposed to this behaviour.

[1] "What Is Really in That MDL?"
    https://docs.microsoft.com/en-us/previous-versions/windows/hardware/design/dn614012(v=vs.85)
[2] https://blogs.msmvps.com/kernelmustard/2005/05/04/dummy-pages/

URL: https://bugzilla.redhat.com/show_bug.cgi?id=1973317
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-02-02 18:50:36 +01:00
Ilya Dryomov
9d5ae6f3c5 libceph: fix "Boolean result is used in bitwise operation" warning
This line dates back to 2013, but cppcheck complained because commit
2f713615dd ("libceph: move msgr1 protocol implementation to its own
file") moved it.  Add parenthesis to silence the warning.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2021-01-21 16:49:59 +01:00
Ilya Dryomov
a56dd9bf47 libceph: move msgr1 protocol specific fields to its own struct
A couple whitespace fixups, no functional changes.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:50 +01:00
Ilya Dryomov
2f713615dd libceph: move msgr1 protocol implementation to its own file
A pure move, no other changes.

Note that ceph_tcp_recv{msg,page}() and ceph_tcp_send{msg,page}()
helpers are also moved.  msgr2 will bring its own, more efficient,
variants based on iov_iter.  Switching msgr1 to them was considered
but decided against to avoid subtle regressions.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-12-14 23:21:50 +01:00