Commit Graph

1738 Commits

Author SHA1 Message Date
Randy Dunlap
4c5fd3b791 zonefs: fix documentation typos etc.
Fix typos, spellos, etc. in zonefs.txt.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Damien Le Moal <Damien.LeMoal@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
2020-02-21 18:09:26 +09:00
Linus Torvalds
380a129eb2 fs: New zonefs file system
Zonefs is a very simple file system exposing each zone of a zoned block
 device as a file.
 
 Unlike a regular file system with native zoned block device support
 (e.g. f2fs or the on-going btrfs effort), zonefs does not hide the
 sequential write constraint of zoned block devices to the user. As a
 result, zonefs is not a POSIX compliant file system. Its goal is to
 simplify the implementation of zoned block devices support in
 applications by replacing raw block device file accesses with a richer
 file based API, avoiding relying on direct block device file ioctls
 which may be more obscure to developers.
 
 One example of this approach is the implementation of LSM
 (log-structured merge) tree structures (such as used in RocksDB and
 LevelDB) on zoned block devices by allowing SSTables to be stored in a
 zone file similarly to a regular file system rather than as a range of
 sectors of a zoned device. The introduction of the higher level
 construct "one file is one zone" can help reducing the amount of changes
 needed in the application while at the same time allowing the use of
 zoned block devices with various programming languages other than C.
 
 Zonefs IO management implementation uses the new iomap generic code.
 Zonefs has been successfully tested using a functional test suite
 (available with zonefs userland format tool on github) and a prototype
 implementation of LevelDB on top of zonefs.
 
 Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQSRPv8tYSvhwAzJdzjdoc3SxdoYdgUCXj1y8QAKCRDdoc3SxdoY
 dqozAP9J3t+Q95BgKgI5jP+XEtyYsPBTaVrvaSaViEnwtJLVoQD/ZQ1lTCZSE9OI
 UkvWawkuFtLGfOxTqyA3eZrZi22Ttwk=
 =YVvO
 -----END PGP SIGNATURE-----

Merge tag 'zonefs-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs

Pull new zonefs file system from Damien Le Moal:
 "Zonefs is a very simple file system exposing each zone of a zoned
  block device as a file.

  Unlike a regular file system with native zoned block device support
  (e.g. f2fs or the on-going btrfs effort), zonefs does not hide the
  sequential write constraint of zoned block devices to the user. As a
  result, zonefs is not a POSIX compliant file system. Its goal is to
  simplify the implementation of zoned block devices support in
  applications by replacing raw block device file accesses with a richer
  file based API, avoiding relying on direct block device file ioctls
  which may be more obscure to developers.

  One example of this approach is the implementation of LSM
  (log-structured merge) tree structures (such as used in RocksDB and
  LevelDB) on zoned block devices by allowing SSTables to be stored in a
  zone file similarly to a regular file system rather than as a range of
  sectors of a zoned device. The introduction of the higher level
  construct "one file is one zone" can help reducing the amount of
  changes needed in the application while at the same time allowing the
  use of zoned block devices with various programming languages other
  than C.

  Zonefs IO management implementation uses the new iomap generic code.
  Zonefs has been successfully tested using a functional test suite
  (available with zonefs userland format tool on github) and a prototype
  implementation of LevelDB on top of zonefs"

* tag 'zonefs-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
  zonefs: Add documentation
  fs: New zonefs file system
2020-02-09 15:51:46 -08:00
Linus Torvalds
c9d35ee049 Merge branch 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs file system parameter updates from Al Viro:
 "Saner fs_parser.c guts and data structures. The system-wide registry
  of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
  the horror switch() in fs_parse() that would have to grow another case
  every time something got added to that system-wide registry.

  New syntax types can be added by filesystems easily now, and their
  namespace is that of functions - not of system-wide enum members. IOW,
  they can be shared or kept private and if some turn out to be widely
  useful, we can make them common library helpers, etc., without having
  to do anything whatsoever to fs_parse() itself.

  And we already get that kind of requests - the thing that finally
  pushed me into doing that was "oh, and let's add one for timeouts -
  things like 15s or 2h". If some filesystem really wants that, let them
  do it. Without somebody having to play gatekeeper for the variants
  blessed by direct support in fs_parse(), TYVM.

  Quite a bit of boilerplate is gone. And IMO the data structures make a
  lot more sense now. -200LoC, while we are at it"

* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
  tmpfs: switch to use of invalfc()
  cgroup1: switch to use of errorfc() et.al.
  procfs: switch to use of invalfc()
  hugetlbfs: switch to use of invalfc()
  cramfs: switch to use of errofc() et.al.
  gfs2: switch to use of errorfc() et.al.
  fuse: switch to use errorfc() et.al.
  ceph: use errorfc() and friends instead of spelling the prefix out
  prefix-handling analogues of errorf() and friends
  turn fs_param_is_... into functions
  fs_parse: handle optional arguments sanely
  fs_parse: fold fs_parameter_desc/fs_parameter_spec
  fs_parser: remove fs_parameter_description name field
  add prefix to fs_context->log
  ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
  new primitive: __fs_parse()
  switch rbd and libceph to p_log-based primitives
  struct p_log, variants of warnf() et.al. taking that one instead
  teach logfc() to handle prefices, give it saner calling conventions
  get rid of cg_invalf()
  ...
2020-02-08 13:26:41 -08:00
Linus Torvalds
f757165705 fuse fixes for 5.6-rc1
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQSQHSd0lITzzeNWNm3h3BK/laaZPAUCXj182AAKCRDh3BK/laaZ
 PIiWAQCprdMIBe0u9Rd9cqQYXClOI7PI9oIcpLmkIlHDuUWDgQD/Y4c1UMsN8yQY
 d8cYZXMivKKhyY2nRitR1mbv0RPoGwE=
 =8hFo
 -----END PGP SIGNATURE-----

Merge tag 'fuse-fixes-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse

Pull fuse fixes from Miklos Szeredi:

 - Fix a regression introduced in v5.1 that triggers WARNINGs for some
   fuse filesystems

 - Fix an xfstest failure

 - Allow overlayfs to be used on top of fuse/virtiofs

 - Code and documentation cleanups

* tag 'fuse-fixes-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: use true,false for bool variable
  Documentation: filesystems: convert fuse to RST
  fuse: Support RENAME_WHITEOUT flag
  fuse: don't overflow LLONG_MAX with end offset
  fix up iter on short count in fuse_direct_io()
2020-02-07 17:59:07 -08:00
Eric Sandeen
96cafb9ccb fs_parser: remove fs_parameter_description name field
Unused now.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:36 -05:00
Al Viro
aa1918f949 get rid of fs_value_is_filename_empty
Its behaviour is identical to that of fs_value_is_filename.
It makes no sense, anyway - LOOKUP_EMPTY affects nothing
whatsoever once the pathname has been imported from userland.
And both fs_value_is_filename and fs_value_is_filename_empty
carry an already imported pathname.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-07 14:48:30 -05:00
Damien Le Moal
fcb9c24bef zonefs: Add documentation
Add the new file Documentation/filesystems/zonefs.txt to document
zonefs principles and user-space tool usage.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2020-02-07 14:40:13 +09:00
Daniel W. S. Almeida
8ab13bca42 Documentation: filesystems: convert fuse to RST
Converts fuse.txt to reStructuredText format, improving the presentation
without changing much of the underlying content.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-02-06 16:39:28 +01:00
Linus Torvalds
6e135baed8 f2fs-for-5.6
In this series, we've implemented transparent compression experimentally. It
 supports LZO and LZ4, but will add more later as we investigate in the field
 more. At this point, the feature doesn't expose compressed space to user
 directly in order to guarantee potential data updates later to the space.
 Instead, the main goal is to reduce data writes to flash disk as much as
 possible, resulting in extending disk life time as well as relaxing IO
 congestion. Alternatively, we're also considering to add ioctl() to reclaim
 compressed space and show it to user after putting the immutable bit.
 
 Enhancement:
  - add compression support
  - avoid unnecessary locks in quota ops
  - harden power-cut scenario for zoned block devices
  - use private bio_set to avoid IO congestion
  - replace GC mutex with rwsem to serialize callers
 
 Bug fix:
  - fix dentry consistency and memory corruption in rename()'s error case
  - fix wrong swap extent reports
  - fix casefolding bugs
  - change lock coverage to avoid deadlock
  - avoid GFP_KERNEL under f2fs_lock_op
 
 And, we've cleaned up sysfs entries to prepare no debugfs.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE00UqedjCtOrGVvQiQBSofoJIUNIFAl4zInwACgkQQBSofoJI
 UNL4Tg/+JBbVEFa3IUBGMdbjfgd/g0Jye++iMAYYGRWT6Ll/IGcHRV9NunITjgWU
 mBZqdhI28kXeiGCcewB1ZvivjLx22X4n6yevHk2B5A6PNe9IDCHi0HOAhJJHkjPH
 ecv2L+vX3Oj4y0+H7JNz9Fo3OIPJvMPtCQWlg1z+VQyhB85zNP7fZlvvIY4tG8yw
 ERo0YNotLqwcF1BxCwNbAhV3aJGDxar+MI//yNzpiwDX7IptVpqestfcoIYc9kKL
 4kSWRyEIGwcuIeyoM6aofGS9t4Z/Oe/gdqcxNr6l5n0Q/tMTpb4b/fJFGNr6RRx9
 X9NQo8flkQb2DEIOP0DVpO2aPebzsVtzg3LZUOLA83+wCHfwINtHai2Dy2zDJ2my
 BrVdou8fe2oxoaYihJg/Tz9cd0nA/6mZArtpYvDImAmX/xuGOvVk9zZkXNwc9nVX
 EyVzy0vW4lA6gAIJ95aG6DDhJcAtVoy0MhBRWG92Pufxhn9aW24AV63ChWUf9DRx
 /3RqpMAuQ3UC2gOxXKKnr54lsdhUIMn/y9sjROkVvQ1BvgRVxO8I4GFvMHMKv9pR
 9KXiVRdzyYERyoL4+MF7A2zTnw+RHL4RVILa85p2ALGy2jQ1UuNUQi0BN9x2u1v8
 S1ifNNX8SwOP+83ImFJhhn3HybpFQ45aLO3F7ZjKBQAnufJu+xw=
 =zeoY
 -----END PGP SIGNATURE-----

Merge tag 'f2fs-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this series, we've implemented transparent compression
  experimentally. It supports LZO and LZ4, but will add more later as we
  investigate in the field more.

  At this point, the feature doesn't expose compressed space to user
  directly in order to guarantee potential data updates later to the
  space. Instead, the main goal is to reduce data writes to flash disk
  as much as possible, resulting in extending disk life time as well as
  relaxing IO congestion.

  Alternatively, we're also considering to add ioctl() to reclaim
  compressed space and show it to user after putting the immutable bit.

  Enhancements:
   - add compression support
   - avoid unnecessary locks in quota ops
   - harden power-cut scenario for zoned block devices
   - use private bio_set to avoid IO congestion
   - replace GC mutex with rwsem to serialize callers

  Bug fixes:
   - fix dentry consistency and memory corruption in rename()'s error case
   - fix wrong swap extent reports
   - fix casefolding bugs
   - change lock coverage to avoid deadlock
   - avoid GFP_KERNEL under f2fs_lock_op

  And, we've cleaned up sysfs entries to prepare no debugfs"

* tag 'f2fs-for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (31 commits)
  f2fs: fix race conditions in ->d_compare() and ->d_hash()
  f2fs: fix dcache lookup of !casefolded directories
  f2fs: Add f2fs stats to sysfs
  f2fs: delete duplicate information on sysfs nodes
  f2fs: change to use rwsem for gc_mutex
  f2fs: update f2fs document regarding to fsync_mode
  f2fs: add a way to turn off ipu bio cache
  f2fs: code cleanup for f2fs_statfs_project()
  f2fs: fix miscounted block limit in f2fs_statfs_project()
  f2fs: show the CP_PAUSE reason in checkpoint traces
  f2fs: fix deadlock allocating bio_post_read_ctx from mempool
  f2fs: remove unneeded check for error allocating bio_post_read_ctx
  f2fs: convert inline_dir early before starting rename
  f2fs: fix memleak of kobject
  f2fs: fix to add swap extent correctly
  f2fs: run fsck when getting bad inode during GC
  f2fs: support data compression
  f2fs: free sysfs kobject
  f2fs: declare nested quota_sem and remove unnecessary sems
  f2fs: don't put new_page twice in f2fs_rename
  ...
2020-01-30 15:39:24 -08:00
Linus Torvalds
e5da4c933c This merge window, we've added some performance improvements in how we
handle inode locking in the read/write paths, and improving the
 performance of Direct I/O overwrites.  We also now record the error
 code which caused the first and most recent ext4_error() report in the
 superblock, to make it easier to root cause problems in production
 systems.  There are also many of the usual cleanups and miscellaneous
 bug fixes.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAl4yBf0ACgkQ8vlZVpUN
 gaOK8Af9EsY1vyR/IvEosfXJoKIqnTXN1SLt94iAOUh6dNeVNcyv1SIzRGFrpmsg
 uHY02EkcTl68b/AjV7ieDpOnOSmlP7NzynuVoar2hrjKX0MzpEu03Vv1a3dUQKuU
 zcdchi83EwRjEvegsNK/VF3FFadk3TtC7x+7o6p840V6OAyp5CXhjm1akJqIJwvd
 A4gTpruTSRIFg6Jj36HEDNRgSAeILed3wC7Ywtxt51tLK7Lp/qB1EuvYodMQRvGz
 d0fRhbNHKepVYfxwpDUDMFnrqDPZ/SZGF73XBxP2zHd6SXy9dBLzGsRL+oj9tTUg
 YQJtt4Yxjjg8Q1UrMyMRzQpi4S8dAQ==
 =pVeR
 -----END PGP SIGNATURE-----

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "This merge window, we've added some performance improvements in how we
  handle inode locking in the read/write paths, and improving the
  performance of Direct I/O overwrites.

  We also now record the error code which caused the first and most
  recent ext4_error() report in the superblock, to make it easier to
  root cause problems in production systems.

  There are also many of the usual cleanups and miscellaneous bug fixes"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (49 commits)
  jbd2: clean __jbd2_journal_abort_hard() and __journal_abort_soft()
  jbd2: make sure ESHUTDOWN to be recorded in the journal superblock
  ext4, jbd2: ensure panic when aborting with zero errno
  jbd2: switch to use jbd2_journal_abort() when failed to submit the commit record
  jbd2_seq_info_next should increase position index
  jbd2: remove pointless assertion in __journal_remove_journal_head
  ext4,jbd2: fix comment and code style
  jbd2: delete the duplicated words in the comments
  ext4: fix extent_status trace points
  ext4: fix symbolic enum printing in trace output
  ext4: choose hardlimit when softlimit is larger than hardlimit in ext4_statfs_project()
  ext4: fix race conditions in ->d_compare() and ->d_hash()
  ext4: make dioread_nolock the default
  ext4: fix extent_status fragmentation for plain files
  jbd2: clear JBD2_ABORT flag before journal_reset to update log tail info when load journal
  ext4: drop ext4_kvmalloc()
  ext4: Add EXT4_IOC_FSGETXATTR/EXT4_IOC_FSSETXATTR to compat_ioctl
  ext4: remove unused macro MPAGE_DA_EXTENT_TAIL
  ext4: add missing braces in ext4_ext_drop_refs()
  ext4: fix some nonstandard indentation in extents.c
  ...
2020-01-30 15:17:05 -08:00
Linus Torvalds
05ef8b97dd It has been a relatively quiet cycle for documentation, but there's still a
couple of things of note:
 
  - Conversion of the NFS documentation to RST
 
  - A new document on how to help with documentation (and a maintainer
    profile entry too)
 
 Plus the usual collection of typo fixes, etc.
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl4wnWwPHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5YFPIH/069z5bJMrT3QRzENu8A9Elz76IXoy7pJOmJ
 53Ml5+c4sYpvV3o6d9n5TSvdy1pH0Shw73FbJzUIMj0ZCcHysWVO1eBDlcj8soJQ
 UonCXbKc+30AJBoKZqAC3jjFw0/fXwD1x+GzQo+l0LMQDOc0i0Luv8/riR5c9hEO
 5TOXB2GyhHnbSFxzcN9afmBsuNz1cPa/fg5q6zL+5Q/fUUOJ6IcYwq165P2EwZdm
 KRah299VU/XhrYlHJX7OZX3ck9+PaYURSpv4KH81J4jhmoBWAw5jPt77Qw8aN3w9
 LcNip+qgpx9wC7OgBiqdJkKcvsNy76pfDhUOj+XarGisA8031d0=
 =9m/7
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.6' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It has been a relatively quiet cycle for documentation, but there's
  still a couple of things of note:

   - Conversion of the NFS documentation to RST

   - A new document on how to help with documentation (and a maintainer
     profile entry too)

  Plus the usual collection of typo fixes, etc"

* tag 'docs-5.6' of git://git.lwn.net/linux: (40 commits)
  docs: filesystems: add overlayfs to index.rst
  docs: usb: remove some broken references
  scripts/find-unused-docs: Fix massive false positives
  docs: nvdimm: use ReST notation for subsection
  zram: correct documentation about sysfs node of huge page writeback
  Documentation: zram: various fixes in zram.rst
  Add a maintainer entry profile for documentation
  Add a document on how to contribute to the documentation
  docs: Keep up with the location of NoUri
  Documentation: Call out example SYM_FUNC_* usage as x86-specific
  Documentation: nfs: fault_injection: convert to ReST
  Documentation: nfs: pnfs-scsi-server: convert to ReST
  Documentation: nfs: convert pnfs-block-server to ReST
  Documentation: nfs: idmapper: convert to ReST
  Documentation: convert nfsd-admin-interfaces to ReST
  Documentation: nfs-rdma: convert to ReST
  Documentation: nfsroot.rst: COSMETIC: refill a paragraph
  Documentation: nfsroot.txt: convert to ReST
  Documentation: convert nfs.txt to ReST
  Documentation: filesystems: convert vfat.txt to RST
  ...
2020-01-29 15:27:31 -08:00
Linus Torvalds
5307040655 Merge branch 'work.adfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull adfs updates from Al Viro:
 "adfs stuff for this cycle"

* 'work.adfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (42 commits)
  fs/adfs: bigdir: Fix an error code in adfs_fplus_read()
  Documentation: update adfs filesystem documentation
  fs/adfs: mostly divorse inode number from indirect disc address
  fs/adfs: super: add support for E and E+ floppy image formats
  fs/adfs: super: extract filesystem block probe
  fs/adfs: dir: remove debug in adfs_dir_update()
  fs/adfs: super: fix inode dropping
  fs/adfs: bigdir: implement directory update support
  fs/adfs: bigdir: calculate and validate directory checkbyte
  fs/adfs: bigdir: directory validation strengthening
  fs/adfs: bigdir: extract directory validation
  fs/adfs: bigdir: factor out directory entry offset calculation
  fs/adfs: newdir: split out directory commit from update
  fs/adfs: newdir: clean up adfs_f_update()
  fs/adfs: newdir: merge adfs_dir_read() into adfs_f_read()
  fs/adfs: newdir: improve directory validation
  fs/adfs: newdir: factor out directory format validation
  fs/adfs: dir: use pointers to access directory head/tails
  fs/adfs: dir: add more efficient iterate() per-format method
  fs/adfs: dir: switch to iterate_shared method
  ...
2020-01-29 11:45:09 -08:00
Linus Torvalds
6aee4badd8 Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull openat2 support from Al Viro:
 "This is the openat2() series from Aleksa Sarai.

  I'm afraid that the rest of namei stuff will have to wait - it got
  zero review the last time I'd posted #work.namei, and there had been a
  leak in the posted series I'd caught only last weekend. I was going to
  repost it on Monday, but the window opened and the odds of getting any
  review during that... Oh, well.

  Anyway, openat2 part should be ready; that _did_ get sane amount of
  review and public testing, so here it comes"

From Aleksa's description of the series:
 "For a very long time, extending openat(2) with new features has been
  incredibly frustrating. This stems from the fact that openat(2) is
  possibly the most famous counter-example to the mantra "don't silently
  accept garbage from userspace" -- it doesn't check whether unknown
  flags are present[1].

  This means that (generally) the addition of new flags to openat(2) has
  been fraught with backwards-compatibility issues (O_TMPFILE has to be
  defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
  kernels gave errors, since it's insecure to silently ignore the
  flag[2]). All new security-related flags therefore have a tough road
  to being added to openat(2).

  Furthermore, the need for some sort of control over VFS's path
  resolution (to avoid malicious paths resulting in inadvertent
  breakouts) has been a very long-standing desire of many userspace
  applications.

  This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset
  (which was a variant of David Drysdale's O_BENEATH patchset[4] which
  was a spin-off of the Capsicum project[5]) with a few additions and
  changes made based on the previous discussion within [6] as well as
  others I felt were useful.

  In line with the conclusions of the original discussion of
  AT_NO_JUMPS, the flag has been split up into separate flags. However,
  instead of being an openat(2) flag it is provided through a new
  syscall openat2(2) which provides several other improvements to the
  openat(2) interface (see the patch description for more details). The
  following new LOOKUP_* flags are added:

  LOOKUP_NO_XDEV:

     Blocks all mountpoint crossings (upwards, downwards, or through
     absolute links). Absolute pathnames alone in openat(2) do not
     trigger this. Magic-link traversal which implies a vfsmount jump is
     also blocked (though magic-link jumps on the same vfsmount are
     permitted).

  LOOKUP_NO_MAGICLINKS:

     Blocks resolution through /proc/$pid/fd-style links. This is done
     by blocking the usage of nd_jump_link() during resolution in a
     filesystem. The term "magic-links" is used to match with the only
     reference to these links in Documentation/, but I'm happy to change
     the name.

     It should be noted that this is different to the scope of
     ~LOOKUP_FOLLOW in that it applies to all path components. However,
     you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it
     will *not* fail (assuming that no parent component was a
     magic-link), and you will have an fd for the magic-link.

     In order to correctly detect magic-links, the introduction of a new
     LOOKUP_MAGICLINK_JUMPED state flag was required.

  LOOKUP_BENEATH:

     Disallows escapes to outside the starting dirfd's
     tree, using techniques such as ".." or absolute links. Absolute
     paths in openat(2) are also disallowed.

     Conceptually this flag is to ensure you "stay below" a certain
     point in the filesystem tree -- but this requires some additional
     to protect against various races that would allow escape using
     "..".

     Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it
     can trivially beam you around the filesystem (breaking the
     protection). In future, there might be similar safety checks done
     as in LOOKUP_IN_ROOT, but that requires more discussion.

  In addition, two new flags are added that expand on the above ideas:

  LOOKUP_NO_SYMLINKS:

     Does what it says on the tin. No symlink resolution is allowed at
     all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this
     can still be used with NOFOLLOW to open an fd for the symlink as
     long as no parent path had a symlink component.

  LOOKUP_IN_ROOT:

     This is an extension of LOOKUP_BENEATH that, rather than blocking
     attempts to move past the root, forces all such movements to be
     scoped to the starting point. This provides chroot(2)-like
     protection but without the cost of a chroot(2) for each filesystem
     operation, as well as being safe against race attacks that
     chroot(2) is not.

     If a race is detected (as with LOOKUP_BENEATH) then an error is
     generated, and similar to LOOKUP_BENEATH it is not permitted to
     cross magic-links with LOOKUP_IN_ROOT.

     The primary need for this is from container runtimes, which
     currently need to do symlink scoping in userspace[7] when opening
     paths in a potentially malicious container.

     There is a long list of CVEs that could have bene mitigated by
     having RESOLVE_THIS_ROOT (such as CVE-2017-1002101,
     CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a
     few).

  In order to make all of the above more usable, I'm working on
  libpathrs[8] which is a C-friendly library for safe path resolution.
  It features a userspace-emulated backend if the kernel doesn't support
  openat2(2). Hopefully we can get userspace to switch to using it, and
  thus get openat2(2) support for free once it's ready.

  Future work would include implementing things like
  RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow
  programs to be sure they don't hit DoSes though stale NFS handles)"

* 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Documentation: path-lookup: include new LOOKUP flags
  selftests: add openat2(2) selftests
  open: introduce openat2(2) syscall
  namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution
  namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
  namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution
  namei: LOOKUP_NO_XDEV: block mountpoint crossing
  namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution
  namei: LOOKUP_NO_SYMLINKS: block symlink resolution
  namei: allow set_root() to produce errors
  namei: allow nd_jump_link() to produce errors
  nsfs: clean-up ns_get_path() signature to return int
  namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-29 11:20:24 -08:00
Mauro Carvalho Chehab
77ce1a47eb docs: filesystems: add overlayfs to index.rst
While the document is there, it is currently missing at the
index file.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/3b8e7783b1fcc71e4f94af5ea8e5fa264392f8c4.1580193653.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-28 13:41:57 -07:00
Hridya Valsaraju
f5fa7c8bb6 f2fs: delete duplicate information on sysfs nodes
This patch merges the sysfs node documentation present in
Documentation/filesystems/f2fs.txt and
Documentation/ABI/testing/sysfs-fs-f2fs
and deletes the duplicate information from
Documentation/filesystems/f2fs.txt. This is to prevent having to update
both files when a new sysfs node is added for f2fs.
The patch also makes minor formatting changes to
Documentation/ABI/testing/sysfs-fs-f2fs.

Signed-off-by: Hridya Valsaraju <hridya@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-01-22 17:14:14 -08:00
Daniel Rosenberg
edc440e3d2 fscrypt: improve format of no-key names
When an encrypted directory is listed without the key, the filesystem
must show "no-key names" that uniquely identify directory entries, are
at most 255 (NAME_MAX) bytes long, and don't contain '/' or '\0'.
Currently, for short names the no-key name is the base64 encoding of the
ciphertext filename, while for long names it's the base64 encoding of
the ciphertext filename's dirhash and second-to-last 16-byte block.

This format has the following problems:

- Since it doesn't always include the dirhash, it's incompatible with
  directories that will use a secret-keyed dirhash over the plaintext
  filenames.  In this case, the dirhash won't be computable from the
  ciphertext name without the key, so it instead must be retrieved from
  the directory entry and always included in the no-key name.
  Casefolded encrypted directories will use this type of dirhash.

- It's ambiguous: it's possible to craft two filenames that map to the
  same no-key name, since the method used to abbreviate long filenames
  doesn't use a proper cryptographic hash function.

Solve both these problems by switching to a new no-key name format that
is the base64 encoding of a variable-length structure that contains the
dirhash, up to 149 bytes of the ciphertext filename, and (if any bytes
remain) the SHA-256 of the remaining bytes of the ciphertext filename.

This ensures that each no-key name contains everything needed to find
the directory entry again, contains only legal characters, doesn't
exceed NAME_MAX, is unambiguous unless there's a SHA-256 collision, and
that we only take the performance hit of SHA-256 on very long filenames.

Note: this change does *not* address the existing issue where users can
modify the 'dirhash' part of a no-key name and the filesystem may still
accept the name.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
[EB: improved comments and commit message, fixed checking return value
 of base64_decode(), check for SHA-256 error, continue to set disk_name
 for short names to keep matching simpler, and many other cleanups]
Link: https://lore.kernel.org/r/20200120223201.241390-7-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:50:03 -08:00
Eric Biggers
f592efe735 fscrypt: clarify what is meant by a per-file key
Now that there's sometimes a second type of per-file key (the dirhash
key), clarify some function names, macros, and documentation that
specifically deal with per-file *encryption* keys.

Link: https://lore.kernel.org/r/20200120223201.241390-4-ebiggers@kernel.org
Reviewed-by: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:49:56 -08:00
Daniel Rosenberg
aa408f835d fscrypt: derive dirhash key for casefolded directories
When we allow indexed directories to use both encryption and
casefolding, for the dirhash we can't just hash the ciphertext filenames
that are stored on-disk (as is done currently) because the dirhash must
be case insensitive, but the stored names are case-preserving.  Nor can
we hash the plaintext names with an unkeyed hash (or a hash keyed with a
value stored on-disk like ext4's s_hash_seed), since that would leak
information about the names that encryption is meant to protect.

Instead, if we can accept a dirhash that's only computable when the
fscrypt key is available, we can hash the plaintext names with a keyed
hash using a secret key derived from the directory's fscrypt master key.
We'll use SipHash-2-4 for this purpose.

Prepare for this by deriving a SipHash key for each casefolded encrypted
directory.  Make sure to handle deriving the key not only when setting
up the directory's fscrypt_info, but also in the case where the casefold
flag is enabled after the fscrypt_info was already set up.  (We could
just always derive the key regardless of casefolding, but that would
introduce unnecessary overhead for people not using casefolding.)

Signed-off-by: Daniel Rosenberg <drosen@google.com>
[EB: improved commit message, updated fscrypt.rst, squashed with change
 that avoids unnecessarily deriving the key, and many other cleanups]
Link: https://lore.kernel.org/r/20200120223201.241390-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:49:55 -08:00
Daniel Rosenberg
6e1918cfb2 fscrypt: don't allow v1 policies with casefolding
Casefolded encrypted directories will use a new dirhash method that
requires a secret key.  If the directory uses a v2 encryption policy,
it's easy to derive this key from the master key using HKDF.  However,
v1 encryption policies don't provide a way to derive additional keys.

Therefore, don't allow casefolding on directories that use a v1 policy.
Specifically, make it so that trying to enable casefolding on a
directory that has a v1 policy fails, trying to set a v1 policy on a
casefolded directory fails, and trying to open a casefolded directory
that has a v1 policy (if one somehow exists on-disk) fails.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
[EB: improved commit message, updated fscrypt.rst, and other cleanups]
Link: https://lore.kernel.org/r/20200120223201.241390-2-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-01-22 14:47:15 -08:00
Russell King
76ed99d199 Documentation: update adfs filesystem documentation
Add an introduction to adfs to its documentation detailing which formats
are supported by the module.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-20 20:12:42 -05:00
Aleksa Sarai
b55eef872a Documentation: path-lookup: include new LOOKUP flags
Now that we have new LOOKUP flags, we should document them in the
relevant path-walking documentation. And now that we've settled on a
common name for nd_jump_link() style symlinks ("magic links"), use that
term where magic-link semantics are described.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-18 09:19:28 -05:00
Jaegeuk Kim
d7b0a23d81 f2fs: update f2fs document regarding to fsync_mode
This patch adds missing fsync_mode entry in f2fs document.

Fixes: 04485987f0 ("f2fs: introduce async IPU policy")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-01-17 16:48:44 -08:00
Jaegeuk Kim
0e7f41974e f2fs: add a way to turn off ipu bio cache
Setting 0x40 in /sys/fs/f2fs/dev/ipu_policy gives a way to turn off
bio cache, which is useufl to check whether block layer using hardware
encryption engine merges IOs correctly.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-01-17 16:48:43 -08:00
Chao Yu
4c8ff7095b f2fs: support data compression
This patch tries to support compression in f2fs.

- New term named cluster is defined as basic unit of compression, file can
be divided into multiple clusters logically. One cluster includes 4 << n
(n >= 0) logical pages, compression size is also cluster size, each of
cluster can be compressed or not.

- In cluster metadata layout, one special flag is used to indicate cluster
is compressed one or normal one, for compressed cluster, following metadata
maps cluster to [1, 4 << n - 1] physical blocks, in where f2fs stores
data including compress header and compressed data.

- In order to eliminate write amplification during overwrite, F2FS only
support compression on write-once file, data can be compressed only when
all logical blocks in file are valid and cluster compress ratio is lower
than specified threshold.

- To enable compression on regular inode, there are three ways:
* chattr +c file
* chattr +c dir; touch dir/file
* mount w/ -o compress_extension=ext; touch file.ext

Compress metadata layout:
                             [Dnode Structure]
             +-----------------------------------------------+
             | cluster 1 | cluster 2 | ......... | cluster N |
             +-----------------------------------------------+
             .           .                       .           .
       .                       .                .                      .
  .         Compressed Cluster       .        .        Normal Cluster            .
+----------+---------+---------+---------+  +---------+---------+---------+---------+
|compr flag| block 1 | block 2 | block 3 |  | block 1 | block 2 | block 3 | block 4 |
+----------+---------+---------+---------+  +---------+---------+---------+---------+
           .                             .
         .                                           .
       .                                                           .
      +-------------+-------------+----------+----------------------------+
      | data length | data chksum | reserved |      compressed data       |
      +-------------+-------------+----------+----------------------------+

Changelog:

20190326:
- fix error handling of read_end_io().
- remove unneeded comments in f2fs_encrypt_one_page().

20190327:
- fix wrong use of f2fs_cluster_is_full() in f2fs_mpage_readpages().
- don't jump into loop directly to avoid uninitialized variables.
- add TODO tag in error path of f2fs_write_cache_pages().

20190328:
- fix wrong merge condition in f2fs_read_multi_pages().
- check compressed file in f2fs_post_read_required().

20190401
- allow overwrite on non-compressed cluster.
- check cluster meta before writing compressed data.

20190402
- don't preallocate blocks for compressed file.

- add lz4 compress algorithm
- process multiple post read works in one workqueue
  Now f2fs supports processing post read work in multiple workqueue,
  it shows low performance due to schedule overhead of multiple
  workqueue executing orderly.

20190921
- compress: support buffered overwrite
C: compress cluster flag
V: valid block address
N: NEW_ADDR

One cluster contain 4 blocks

 before overwrite   after overwrite

- VVVV		->	CVNN
- CVNN		->	VVVV

- CVNN		->	CVNN
- CVNN		->	CVVV

- CVVV		->	CVNN
- CVVV		->	CVVV

20191029
- add kconfig F2FS_FS_COMPRESSION to isolate compression related
codes, add kconfig F2FS_FS_{LZO,LZ4} to cover backend algorithm.
note that: will remove lzo backend if Jaegeuk agreed that too.
- update codes according to Eric's comments.

20191101
- apply fixes from Jaegeuk

20191113
- apply fixes from Jaegeuk
- split workqueue for fsverity

20191216
- apply fixes from Jaegeuk

20200117
- fix to avoid NULL pointer dereference

[Jaegeuk Kim]
- add tracepoint for f2fs_{,de}compress_pages()
- fix many bugs and add some compression stats
- fix overwrite/mmap bugs
- address 32bit build error, reported by Geert.
- bug fixes when handling errors and i_compressed_blocks

Reported-by: <noreply@ellerman.id.au>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2020-01-17 16:48:07 -08:00
Eric Biggers
457b1e353c ext4: allow ZERO_RANGE on encrypted files
When ext4 encryption support was first added, ZERO_RANGE was disallowed,
supposedly because test failures (e.g. ext4/001) were seen when enabling
it, and at the time there wasn't enough time/interest to debug it.

However, there's actually no reason why ZERO_RANGE can't work on
encrypted files.  And it fact it *does* work now.  Whole blocks in the
zeroed range are converted to unwritten extents, as usual; encryption
makes no difference for that part.  Partial blocks are zeroed in the
pagecache and then ->writepages() encrypts those blocks as usual.
ext4_block_zero_page_range() handles reading and decrypting the block if
needed before actually doing the pagecache write.

Also, f2fs has always supported ZERO_RANGE on encrypted files.

As far as I can tell, the reason that ext4/001 was failing in v4.1 was
actually because of one of the bugs fixed by commit 36086d43f6 ("ext4
crypto: fix bugs in ext4_encrypted_zeroout()").  The bug made
ext4_encrypted_zeroout() always return a positive value, which caused
unwritten extents in encrypted files to sometimes not be marked as
initialized after being written to.  This bug was not actually in
ZERO_RANGE; it just happened to trigger during the extents manipulation
done in ext4/001 (and probably other tests too).

So, let's enable ZERO_RANGE on encrypted files on ext4.

Tested with:
	gce-xfstests -c ext4/encrypt -g auto
	gce-xfstests -c ext4/encrypt_1k -g auto

Got the same set of test failures both with and without this patch.
But with this patch 6 fewer tests are skipped: ext4/001, generic/008,
generic/009, generic/033, generic/096, and generic/511.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191226154216.4808-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2020-01-17 16:24:53 -05:00
Daniel W. S. Almeida
6996e8ca8b Documentation: nfs: fault_injection: convert to ReST
Convert fault_injection.txt to ReST and move it to admin-guide.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/f7b0cf8fb1159a668f75ce82a581e7590568c2b8.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
98600b71f2 Documentation: nfs: pnfs-scsi-server: convert to ReST
Convert pnfs-scsi-server to ReST and move it to admin-guide. Content
remains mostly unchanged.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/5c4b8af41ca0a427a3987535815bccf47a65d320.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
26f6225fa5 Documentation: nfs: convert pnfs-block-server to ReST
Convert pnfs-block-server.txt to ReST and move it to admin-guide.
Content remains mostly unchanged.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/c06903760e690c16d9df92f5e75f80381d6326d8.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
fbdcd0b8e5 Documentation: nfs: idmapper: convert to ReST
Convert idmapper.txt to ReST and move it to admin-guide.
Content remains mostly unchanged otherwise.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/069e40cd551ea778538f8fe9ad15ee26e45fc748.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
0f3456ba9f Documentation: convert nfsd-admin-interfaces to ReST
Convert nfsd-admin-interfaces to ReST and move it into admin-guide.
Content remains mostly untouched.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/d471305e9c96dec38f18d2ff816fca2269a88e29.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:05 -07:00
Daniel W. S. Almeida
f8b8d03059 Documentation: nfs-rdma: convert to ReST
Convert nfs-rdma to ReST and move it to admin-guide. Content
remais mostly untouched. Also, mark the doc as obsolete.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/9c88f184f9de2a3eb5181563e258559efc02f58a.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:04 -07:00
Daniel W. S. Almeida
f9a9349846 Documentation: nfsroot.txt: convert to ReST
Convert nfsroot.txt to RST and move it to admin-guide. Content remains
mostly the same.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/442d35917351f5260dd8ed7362e9b5f1264ef8ad.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:04 -07:00
Daniel W. S. Almeida
2f123b9a35 Documentation: convert nfs.txt to ReST
This patch converts nfs.txt to RST. It also moves it to admin-guide.
The reason for moving it is because this document contains information
useful for system administrators, as noted on the following paragraph:

'The purpose of this document is to provide information on some of the
special features of the NFS client that can be configured by system
administrators'.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
Link: https://lore.kernel.org/r/cb9f2da2f2f6dd432b4cf9e05f79f74f4d54b6ab.1578697871.git.dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-16 12:43:04 -07:00
Daniel W. S. Almeida
a1986433a9 Documentation: filesystems: convert vfat.txt to RST
Converts vfat.txt to the reStructuredText format, improving presentation
without changing the underlying content.

Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
-----------------------------------------------------------
Changes in v3:
Removed unnecessary markup.
Removed section "BUG REPORTS" as recommended by the maintainer.

Changes in v2:
Refactored long lines as pointed out by Jonathan
Copied the maintainer
Updated the reference in the MAINTAINERS file for vfat

I did not move this into admin-guide, waiting on what the
maintainer has to say about this and also about old sections
in the text, if any.

Link: https://lore.kernel.org/r/20191223010030.434902-1-dwlsalmeida@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-01-10 10:58:45 -07:00
Eric Biggers
93edd392ca fscrypt: support passing a keyring key to FS_IOC_ADD_ENCRYPTION_KEY
Extend the FS_IOC_ADD_ENCRYPTION_KEY ioctl to allow the raw key to be
specified by a Linux keyring key, rather than specified directly.

This is useful because fscrypt keys belong to a particular filesystem
instance, so they are destroyed when that filesystem is unmounted.
Usually this is desired.  But in some cases, userspace may need to
unmount and re-mount the filesystem while keeping the keys, e.g. during
a system update.  This requires keeping the keys somewhere else too.

The keys could be kept in memory in a userspace daemon.  But depending
on the security architecture and assumptions, it can be preferable to
keep them only in kernel memory, where they are unreadable by userspace.

We also can't solve this by going back to the original fscrypt API
(where for each file, the master key was looked up in the process's
keyring hierarchy) because that caused lots of problems of its own.

Therefore, add the ability for FS_IOC_ADD_ENCRYPTION_KEY to accept a
Linux keyring key.  This solves the problem by allowing userspace to (if
needed) save the keys securely in a Linux keyring for re-provisioning,
while still using the new fscrypt key management ioctls.

This is analogous to how dm-crypt accepts a Linux keyring key, but the
key is then stored internally in the dm-crypt data structures rather
than being looked up again each time the dm-crypt device is accessed.

Use a custom key type "fscrypt-provisioning" rather than one of the
existing key types such as "logon".  This is strongly desired because it
enforces that these keys are only usable for a particular purpose: for
fscrypt as input to a particular KDF.  Otherwise, the keys could also be
passed to any kernel API that accepts a "logon" key with any service
prefix, e.g. dm-crypt, UBIFS, or (recently proposed) AF_ALG.  This would
risk leaking information about the raw key despite it ostensibly being
unreadable.  Of course, this mistake has already been made for multiple
kernel APIs; but since this is a new API, let's do it right.

This patch has been tested using an xfstest which I wrote to test it.

Link: https://lore.kernel.org/r/20191119222447.226853-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2019-12-31 10:33:49 -06:00
Madhuparna Bhowmik
a83aaf4979 Documentation: filesystems: automount-support: Change reference to document autofs.txt to autofs.rst
This patch fixes following documentation build warning:
Warning: Documentation/filesystems/automount-support.txt references
a file that doesn't exist: Documentation/filesystems/autofs.txt

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik04@gmail.com>
Link: https://lore.kernel.org/r/20191204101939.6939-1-madhuparnabhowmik04@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-12-19 09:35:51 -07:00
Linus Torvalds
81c64b0bd0 overlayfs fixes for 5.5-rc2
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQSQHSd0lITzzeNWNm3h3BK/laaZPAUCXfNhGQAKCRDh3BK/laaZ
 PGSEAP9Nyv3XCN2wdqMLdrgn07B3Pk9w2Unf3Y5amKOxNXqyQwEAy2/E6DCiGjSa
 WRheJoTgDSeqUQNY6GFHsCIgLWOCHgs=
 =WH5O
 -----END PGP SIGNATURE-----

Merge tag 'ovl-fixes-5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs

Pull overlayfs fixes from Miklos Szeredi:
 "Fix some bugs and documentation"

* tag 'ovl-fixes-5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  docs: filesystems: overlayfs: Fix restview warnings
  docs: filesystems: overlayfs: Rename overlayfs.txt to .rst
  ovl: relax WARN_ON() on rename to self
  ovl: fix corner case of non-unique st_dev;st_ino
  ovl: don't use a temp buf for encoding real fh
  ovl: make sure that real fid is 32bit aligned in memory
  ovl: fix lookup failure on multi lower squashfs
2019-12-14 11:13:54 -08:00
Linus Torvalds
687dec9b94 Changes since last update:
- Fix improper return value of listxattr() with no xattr;
 
 - Keep up documentation with latest code.
 -----BEGIN PGP SIGNATURE-----
 
 iIwEABYIADQWIQThPAmQN9sSA0DVxtI5NzHcH7XmBAUCXfELlBYcZ2FveGlhbmcy
 NUBodWF3ZWkuY29tAAoJEDk3MdwfteYEtUABAN164UwGU9QKEsqgZQcmbz23qXSJ
 QDR8r/ch2LxzXKkVAQDXCNU+ol6jkiapLcTvsXEjBk8sUxsCEVnmZ36jru+TBA==
 =kRp9
 -----END PGP SIGNATURE-----

Merge tag 'erofs-for-5.5-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs

Pull erofs fixes from Gao Xiang:
 "Mainly address a regression reported by David recently observed
  together with overlayfs due to the improper return value of
  listxattr() without xattr. Update outdated expressions in document as
  well.

  Summary:

   - Fix improper return value of listxattr() with no xattr

   - Keep up documentation with latest code"

* tag 'erofs-for-5.5-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
  erofs: update documentation
  erofs: zero out when listxattr is called with no xattr
2019-12-11 12:25:32 -08:00
Amir Goldstein
35c6cb4168 docs: filesystems: overlayfs: Fix restview warnings
Fix only the obvious problems

[SzM: add SPDX license line]

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-12-10 16:00:55 +01:00
Amir Goldstein
5356ab0644 docs: filesystems: overlayfs: Rename overlayfs.txt to .rst
It is already formatted as RST.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-12-10 16:00:55 +01:00
Gao Xiang
ffafde4783 erofs: update documentation
Some on-disk structures, fields have been renamed in v5.4,
the corresponding document should be updated as well.

Also fix misrespresentation of file time and words about
fixed-sized output compression, data inline, etc.

Link: https://lore.kernel.org/r/20191207025509.6614-1-hsiangkao@aol.com/
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
2019-12-08 21:37:01 +08:00
Linus Torvalds
937d6eefc7 Here's the main documentation changes for 5.5:
- Various kerneldoc script enhancements.
 
  - More RST conversions; those are slowing down as we run out of things to
    convert, but we're a ways from done still.
 
  - Dan's "maintainer profile entry" work landed at last.  Now we just need
    to get maintainers to fill in the profiles...
 
  - A reworking of the parallel build setup to work better with a variety of
    systems (and to not take over huge systems entirely in particular).
 
  - The MAINTAINERS file is now converted to RST during the build.
    Hopefully nobody ever tries to print this thing, or they will need to
    load a lot of paper.
 
  - A script and documentation making it easy for maintainers to add Link:
    tags at commit time.
 
 Also included is the removal of a bunch of spurious CR characters.
 -----BEGIN PGP SIGNATURE-----
 
 iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl3j5B0PHGNvcmJldEBs
 d24ubmV0AAoJEBdDWhNsDH5YtBcH/jIN2cO8/0YW2rjVT+1G6ytSdFUKx5WJ/lpf
 5uBeCvuCeYhtCB6+BgnXvjykJ7jDW11/NJNjWqz/gsvD5l5FJK1rXarI/oz2Klyi
 kcPtDmBF/ki4wz9qXzEpa0vg8LXdjeys50S1vE75qCzxZoPP7YjuRbPnLrlIJukv
 JbDVi4p9kxgeHfRB4+BHOe5rFwA3mMmaxKNIX34Y+UUO2KZ0g/yUi1bAaQwQAdt+
 PsORmkVQ8Puh3K9xRIr7dYlcWBlBiPqzYdvDgTVxSjrxdK6wjYjSgVk2VjC5MBUN
 mTSTWgyfsIcD/76/s8tq7ZRl2fw+SkCSkFo79Rb/hJwDTb7Vnng=
 =LPBr
 -----END PGP SIGNATURE-----

Merge tag 'docs-5.5a' of git://git.lwn.net/linux

Pull Documentation updates from Jonathan Corbet:
 "Here are the main documentation changes for 5.5:

   - Various kerneldoc script enhancements.

   - More RST conversions; those are slowing down as we run out of
     things to convert, but we're a ways from done still.

   - Dan's "maintainer profile entry" work landed at last. Now we just
     need to get maintainers to fill in the profiles...

   - A reworking of the parallel build setup to work better with a
     variety of systems (and to not take over huge systems entirely in
     particular).

   - The MAINTAINERS file is now converted to RST during the build.
     Hopefully nobody ever tries to print this thing, or they will need
     to load a lot of paper.

   - A script and documentation making it easy for maintainers to add
     Link: tags at commit time.

  Also included is the removal of a bunch of spurious CR characters"

* tag 'docs-5.5a' of git://git.lwn.net/linux: (91 commits)
  docs: remove a bunch of stray CRs
  docs: fix up the maintainer profile document
  libnvdimm, MAINTAINERS: Maintainer Entry Profile
  Maintainer Handbook: Maintainer Entry Profile
  MAINTAINERS: Reclaim the P: tag for Maintainer Entry Profile
  docs, parallelism: Rearrange how jobserver reservations are made
  docs, parallelism: Do not leak blocking mode to other readers
  docs, parallelism: Fix failure path and add comment
  Documentation: Remove bootmem_debug from kernel-parameters.txt
  Documentation: security: core.rst: fix warnings
  Documentation/process/howto/kokr: Update for 4.x -> 5.x versioning
  Documentation/translation: Use Korean for Korean translation title
  docs/memory-barriers.txt: Remove remaining references to mmiowb()
  docs/memory-barriers.txt/kokr: Update I/O section to be clearer about CPU vs thread
  docs/memory-barriers.txt/kokr: Fix style, spacing and grammar in I/O section
  Documentation/kokr: Kill all references to mmiowb()
  docs/memory-barriers.txt/kokr: Rewrite "KERNEL I/O BARRIER EFFECTS" section
  docs: Add initial documentation for devfreq
  Documentation: Document how to get links with git am
  docs: Add request_irq() documentation
  ...
2019-12-02 11:51:02 -08:00
Linus Torvalds
8f45533e9d f2fs-for-5.5-rc1
In this round, we've introduced fairly small number of patches as below.
 
 Enhancement:
  - improve the in-place-update IO flow
  - allocate segment to guarantee no GC for pinned files
 
 Bug fix:
  - fix updatetime in lazytime mode
  - potential memory leak in f2fs_listxattr
  - record parent inode number in rename2 correctly
  - fix deadlock in f2fs_gc along with atomic writes
  - avoid needless data migration in GC
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE00UqedjCtOrGVvQiQBSofoJIUNIFAl3e1XkACgkQQBSofoJI
 UNJ0GhAAhVIX4J91CLnVSh0ik1XCaI6h/dFeS6kbDd8oxzQm/qt64b59aZqgy7Rk
 iblGWfj8uPP5yO60pqb5uN4a0hybptVZSEldbhF0Xv0zUeVoT7C1ksTMrdUd1p7d
 YkO8G+V4QBBrtpKG1KKKEncrvcdx4n9QHxGsRh4z5vXZH7sEmH7+N8OE88MaPjdZ
 UWqYk0S0GoZBhPe7c8pQuD/PM+WJJH4Lewgw5kK21eAjOKI+yZKb+bY2tGjo5dA1
 nzYO72CRMV4VEKsnxTZ/LCB2kCXeexaGuiVPyHjCmgAh990cLjsCWIbJ8EJu7uAa
 vAo6/EMfgfPkPt5Y7uWGR4EeNT7AFhUoMuoQ9zdXzecY48D4Gz58o87Q+OFY3ipZ
 W2OSf92pEJyfumE5o8wN435gaRYUjjCo1SMoIQABNav411XrBVoRwjvkV3DyA6af
 Bs1bafz2hR/E1q0uoZvLWC5waiHy9605OkKMs/y8IRsn6yhRep/tv3KLk2Dz3fOO
 LxenhuVO9bQDCheEcH15qIljxTuyfTyUOa9UrFXOwn4mK61J8A/Gs+SiqW0y28oA
 feSw7cLPxK0OlYQgql24JfJN/Xt523WmCSfXfe7TCUDTDkBpmsdhFwHYZyCLzqt+
 FyBhf2DF/BGzKMT28oc7StO43mIvOc1Wk+jfJFW+hld5ncAJxCE=
 =qyrd
 -----END PGP SIGNATURE-----

Merge tag 'f2fs-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've introduced fairly small number of patches as below.

  Enhancements:
   - improve the in-place-update IO flow
   - allocate segment to guarantee no GC for pinned files

  Bug fixes:
   - fix updatetime in lazytime mode
   - potential memory leak in f2fs_listxattr
   - record parent inode number in rename2 correctly
   - fix deadlock in f2fs_gc along with atomic writes
   - avoid needless data migration in GC"

* tag 'f2fs-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
  f2fs: stop GC when the victim becomes fully valid
  f2fs: expose main_blkaddr in sysfs
  f2fs: choose hardlimit when softlimit is larger than hardlimit in f2fs_statfs_project()
  f2fs: Fix deadlock in f2fs_gc() context during atomic files handling
  f2fs: show f2fs instance in printk_ratelimited
  f2fs: fix potential overflow
  f2fs: fix to update dir's i_pino during cross_rename
  f2fs: support aligned pinned file
  f2fs: avoid kernel panic on corruption test
  f2fs: fix wrong description in document
  f2fs: cache global IPU bio
  f2fs: fix to avoid memory leakage in f2fs_listxattr
  f2fs: check total_segments from devices in raw_super
  f2fs: update multi-dev metadata in resize_fs
  f2fs: mark recovery flag correctly in read_raw_super_block()
  f2fs: fix to update time in lazytime mode
2019-11-30 11:02:30 -08:00
Linus Torvalds
50b8b3f85a This merge window saw the the following new featuers added to ext4:
* Direct I/O via iomap (required the iomap-for-next branch from Darrick
    as a prereq).
  * Support for using dioread-nolock where the block size < page size.
  * Support for encryption for file systems where the block size < page size.
  * Rework of journal credits handling so a revoke-heavy workload will
    not cause the journal to run out of space.
  * Replace bit-spinlocks with spinlocks in jbd2
 
 Also included were some bug fixes and cleanups, mostly to clean up
 corner cases from fuzzed file systems and error path handling.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAl3dHxoACgkQ8vlZVpUN
 gaMZswf5AbtQhTEJDXO7Pc1ull38GIGFgAv7uAth0TymLC3h1/FEYWW0crEPFsDr
 1Eei55UUVOYrMMUKQ4P7wlLX0cIh3XDPMWnRFuqBoV5/ZOsH/ZSbkY//TG2Xze/v
 9wXIH/RKQnzbRtXffJ1+DnvmXJk+HFm1R1gjl0nfyUXGrnlSfqJxhLSczyd6bJJq
 ehi/tso5UC/4EQsAIdWp7VWsAdaHcZ7ogHqDoy8dXpM1equ408iml7VlKr8R+Nr7
 5ANpCISXChSlLLYm0NYN5vhO8upF5uDxWLdCtxVPL5kFdM2m/ELjXw9h9C+78l7C
 EWJGlGlxvx07Px+e+bfStEsoixpWBg==
 =0eko
 -----END PGP SIGNATURE-----

Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "This merge window saw the the following new featuers added to ext4:

   - Direct I/O via iomap (required the iomap-for-next branch from
     Darrick as a prereq).

   - Support for using dioread-nolock where the block size < page size.

   - Support for encryption for file systems where the block size < page
     size.

   - Rework of journal credits handling so a revoke-heavy workload will
     not cause the journal to run out of space.

   - Replace bit-spinlocks with spinlocks in jbd2

  Also included were some bug fixes and cleanups, mostly to clean up
  corner cases from fuzzed file systems and error path handling"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (59 commits)
  ext4: work around deleting a file with i_nlink == 0 safely
  ext4: add more paranoia checking in ext4_expand_extra_isize handling
  jbd2: make jbd2_handle_buffer_credits() handle reserved handles
  ext4: fix a bug in ext4_wait_for_tail_page_commit
  ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails
  ext4: code cleanup for get_next_id
  ext4: fix leak of quota reservations
  ext4: remove unused variable warning in parse_options()
  ext4: Enable encryption for subpage-sized blocks
  fs/buffer.c: support fscrypt in block_read_full_page()
  ext4: Add error handling for io_end_vec struct allocation
  jbd2: Fine tune estimate of necessary descriptor blocks
  jbd2: Provide trace event for handle restarts
  ext4: Reserve revoke credits for freed blocks
  jbd2: Make credit checking more strict
  jbd2: Rename h_buffer_credits to h_total_credits
  jbd2: Reserve space for revoke descriptor blocks
  jbd2: Drop jbd2_space_needed()
  jbd2: Account descriptor blocks into t_outstanding_credits
  jbd2: Factor out common parts of stopping and restarting a handle
  ...
2019-11-30 10:53:02 -08:00
Linus Torvalds
9a3d7fd275 Driver core patches for 5.5-rc1
Here is the "big" set of driver core patches for 5.5-rc1
 
 There's a few minor cleanups and fixes in here, but the majority of the
 patches in here fall into two buckets:
   - debugfs api cleanups and fixes
   - driver core device link support for boot dependancy issues
 
 The debugfs api cleanups are working to slowly refactor the debugfs apis
 so that it is even harder to use incorrectly.  That work has been
 happening for the past few kernel releases and will continue over time,
 it's a long-term project/goal
 
 The driver core device link support missed 5.4 by just a bit, so it's
 been sitting and baking for many months now.  It's from Saravana Kannan
 to help resolve the problems that DT-based systems have at boot time
 with dependancy graphs and kernel modules.  Turns out that no one has
 actually tried to build a generic arm64 kernel with loads of modules and
 have it "just work" for a variety of platforms (like a distro kernel)
 The big problem turned out to be a lack of depandancy information
 between different areas of DT entries, and the work here resolves that
 problem and now allows devices to boot properly, and quicker than a
 monolith kernel.
 
 All of these patches have been in linux-next for a long time with no
 reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXd6m6Q8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+yntJQCcCqg6RQ7LTdHuZv1ETeefXlsfk00An1Jtean6
 42bWGx52bGFvAcpjWy8R
 =P7hq
 -----END PGP SIGNATURE-----

Merge tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.5-rc1

  There's a few minor cleanups and fixes in here, but the majority of
  the patches in here fall into two buckets:

   - debugfs api cleanups and fixes

   - driver core device link support for boot dependancy issues

  The debugfs api cleanups are working to slowly refactor the debugfs
  apis so that it is even harder to use incorrectly. That work has been
  happening for the past few kernel releases and will continue over
  time, it's a long-term project/goal

  The driver core device link support missed 5.4 by just a bit, so it's
  been sitting and baking for many months now. It's from Saravana Kannan
  to help resolve the problems that DT-based systems have at boot time
  with dependancy graphs and kernel modules. Turns out that no one has
  actually tried to build a generic arm64 kernel with loads of modules
  and have it "just work" for a variety of platforms (like a distro
  kernel). The big problem turned out to be a lack of dependency
  information between different areas of DT entries, and the work here
  resolves that problem and now allows devices to boot properly, and
  quicker than a monolith kernel.

  All of these patches have been in linux-next for a long time with no
  reported issues"

* tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (68 commits)
  tracing: Remove unnecessary DEBUG_FS dependency
  of: property: Add device link support for interrupt-parent, dmas and -gpio(s)
  debugfs: Fix !DEBUG_FS debugfs_create_automount
  of: property: Add device link support for "iommu-map"
  of: property: Fix the semantics of of_is_ancestor_of()
  i2c: of: Populate fwnode in of_i2c_get_board_info()
  drivers: base: Fix Kconfig indentation
  firmware_loader: Fix labels with comma for builtin firmware
  driver core: Allow device link operations inside sync_state()
  driver core: platform: Declare ret variable only once
  cpu-topology: declare parse_acpi_topology in <linux/arch_topology.h>
  crypto: hisilicon: no need to check return value of debugfs_create functions
  driver core: platform: use the correct callback type for bus_find_device
  firmware_class: make firmware caching configurable
  driver core: Clarify documentation for fwnode_operations.add_links()
  mailbox: tegra: Fix superfluous IRQ error message
  net: caif: Fix debugfs on 64-bit platforms
  mac80211: Use debugfs_create_xul() helper
  media: c8sectpfe: no need to check return value of debugfs_create functions
  of: property: Add device link support for iommus, mboxes and io-channels
  ...
2019-11-27 11:06:20 -08:00
Linus Torvalds
1c1ff4836f fsverity updates for 5.5
Expose the fs-verity bit through statx().
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQSacvsUNc7UX4ntmEPzXCl4vpKOKwUCXdtWqhQcZWJpZ2dlcnNA
 Z29vZ2xlLmNvbQAKCRDzXCl4vpKOK+C9AQCCf8C2KP6DynoGQb9KRYYreJk8js8G
 IgtlhazJ3j1RJAD/VijFbdwbxGCmiR1Y6BhKq5eaCYD1El68wSwkKuNO3ww=
 =7WpU
 -----END PGP SIGNATURE-----

Merge tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt

Pull fsverity updates from Eric Biggers:
 "Expose the fs-verity bit through statx()"

* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  docs: fs-verity: mention statx() support
  f2fs: support STATX_ATTR_VERITY
  ext4: support STATX_ATTR_VERITY
  statx: define STATX_ATTR_VERITY
  docs: fs-verity: document first supported kernel version
2019-11-25 12:21:23 -08:00
Jaegeuk Kim
a4db59ac90 f2fs: expose main_blkaddr in sysfs
Expose in /sys/fs/f2fs/<blockdev>/main_blkaddr the block address where the
main area starts. This allows user mode programs to determine:

- That pinned files that are made exclusively of fully allocated 2MB
  segments will never be unpinned by the file system.

- Where the main area starts. This is required by programs that want to
  verify if a file is made exclusively of 2MB f2fs segments, the alignment
  boundary for segments starts at this address. Testing for 2MB alignment
  relative to the start of the device is incorrect, because for some
  filesystems main_blkaddr is not at a 2MB boundary relative to the start
  of the device.

The entry will be used when validating reliable pinning file feature proposed
by "f2fs: support aligned pinned file".

Signed-off-by: Ramon Pantin <pantin@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-25 10:01:27 -08:00
Jaskaran Singh
e8a9e30d72 docs: filesystems: Add mount map description in Content
The second paragraph of the content section does not properly
describe how mount points are determined by autofs.

Replace the lines detailing how the determination of these mount
points is "ad hoc" by a short description of the mount map syntax
used by autofs.

Signed-off-by: Jaskaran Singh <jaskaransingh7654321@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-18 12:19:59 -07:00
Jaskaran Singh
c11565e887 docs: filesystems: Update code snippets in autofs.rst
Some of the struct definitions now have an autofs packet header.
Reflect these changes by adding a definition of this header and
place it wherever suitable.

Signed-off-by: Jaskaran Singh <jaskaransingh7654321@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-18 12:19:53 -07:00
Jaskaran Singh
f11f2a3c54 docs: filesystems: convert autofs.txt to reST
Convert autofs.txt to reST.

The following changes abound:

- Introduce reST formatting for headings, lists et al.
- Add an indentation of an 8 space tab wherever suitable, so as
  to maintain consistency.
- Remove indentation of the description of the ioctls which are similar
  to the AUTOFS_IOC ioctls, as it does not come out quite right in HTML.
- Add an entry for autofs in the index.

Signed-off-by: Jaskaran Singh <jaskaransingh7654321@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-11-18 12:17:17 -07:00