[Qemu-devel] [PATCH v5 0/5] 9p: Fix file ID collisions

[Christian Schoenebeck via Qemu-devel <qemu-devel@nongnu.org>]

This is v5 of a proposed patch set for fixing file ID collisions with 9pfs.

v4->v5:

  All Patches:

  * Added details to individual commit logs of what has been changed
    exactly by me on top of Antonios' original 4 patches.

  Patch 1:

  * Fixed format specifiers in hw/9pfs/trace-events.

  Patch 2:

  * Fixed typo in commit log.

  * Assign dev_id to export root's device already in
    v9fs_device_realize_common(), not postponed in stat_to_qid().

  * Return -ENODEV instead of -ENOSYS in stat_to_qid().

  Patch 3:

  * Added missing manual parts for new virtfs option 'remap_inodes' in
    qemu-options.hx.

  * Capture root_ino in v9fs_device_realize_common() as well, not just the
    device id.

  * Added function dirent_to_qid().

  * Fixed v9fs_do_readdir() having exposed info outside export root with
    '..' entry (no matter if inode remapping was on or not).

  * Fixed v9fs_do_readdir() not having remapped inodes.

  * Fixed definition of QPATH_INO_MASK.

  * Log error message when running out of prefixes in qid_path_prefixmap().

  * Adjusted changes in stat_to_qid() to qemu code style guidelines.

  Patch 4:

  * Log error message when running out of prefixes in qid_path_fullmap().

  * Log error message about potential degraded performance in
    qid_path_prefixmap() (that is when qid_path_fullmap() will start to
    kick in next).

  * Fixed typo in code comment.

  Patch 5:

  * Dropped fixed (16 bit) size prefix code and hence removed usage of
    P9_VARI_LENGTH_INODE_SUFFIXES macro checks all over the place.

  * Dropped function expGolombEncodeK0(uint64_t n) which was optimized for
    the expected default value of k=0; instead always use the generalized
    function expGolombEncode(uint64_t n, int k) instead now.

  * Adjusted changes in hw/9pfs/9p.c to qemu code style guidelines.

  * Adjusted functions' API comments in hw/9pfs/9p.c.

v3->v4:

  * Rebased to latest git master head.

  * Splitted Antonios' patch set to its original 4 individual patches.
    (was merged previously as only 1 patch).

  * Addressed discussed issues directly on Antonios' patches
    (was a separate patch before).

  * Added virtfs command line option "remap_inodes": Unless this option
    is not enabled, no inode remapping is performed at all, the user
    just gets an error message when trying to use more than 1 device
    per export.

  * Dropped persistency feature of QIDs beyond reboots.

  * Dropped disputed "vii" feature.

Christian Schoenebeck (5):
  9p: unsigned type for type, version, path
  9p: Treat multiple devices on one export as an error
  9p: Added virtfs option 'remap_inodes'
  9p: stat_to_qid: implement slow path
  9p: Use variable length suffixes for inode remapping

 fsdev/9p-marshal.h      |   6 +-
 fsdev/file-op-9p.h      |   1 +
 fsdev/qemu-fsdev-opts.c |   7 +-
 fsdev/qemu-fsdev.c      |   6 +
 hw/9pfs/9p.c            | 508 +++++++++++++++++++++++++++++++++++++++++++++---
 hw/9pfs/9p.h            |  51 +++++
 hw/9pfs/trace-events    |  14 +-
 qemu-options.hx         |  25 ++-
 vl.c                    |   3 +
 9 files changed, 573 insertions(+), 48 deletions(-)

-- 
2.11.0