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  1. 14 7月, 2012 6 次提交
  3. 08 7月, 2012 1 次提交
  5. 02 6月, 2012 4 次提交
  7. 03 5月, 2012 2 次提交
  9. 10 4月, 2012 1 次提交
  11. 20 2月, 2012 1 次提交
    • D
      Wrap accesses to the fd_sets in struct fdtable · 1dce27c5
      由 David Howells 提交于 
      Wrap accesses to the fd_sets in struct fdtable (for recording open files and
close-on-exec flags) so that we can move away from using fd_sets since we
abuse the fd_set structs by not allocating the full-sized structure under
normal circumstances and by non-core code looking at the internals of the
fd_sets.

The first abuse means that use of FD_ZERO() on these fd_sets is not permitted,
since that cannot be told about their abnormal lengths.

This introduces six wrapper functions for setting, clearing and testing
close-on-exec flags and fd-is-open flags:

	void __set_close_on_exec(int fd, struct fdtable *fdt);
	void __clear_close_on_exec(int fd, struct fdtable *fdt);
	bool close_on_exec(int fd, const struct fdtable *fdt);
	void __set_open_fd(int fd, struct fdtable *fdt);
	void __clear_open_fd(int fd, struct fdtable *fdt);
	bool fd_is_open(int fd, const struct fdtable *fdt);

Note that I've prepended '__' to the names of the set/clear functions because
they require the caller to hold a lock to use them.

Note also that I haven't added wrappers for looking behind the scenes at the
the array.  Possibly that should exist too.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20120216174942.23314.1364.stgit@warthog.procyon.org.ukSigned-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
      1dce27c5
  13. 07 1月, 2012 1 次提交
  15. 04 1月, 2012 3 次提交
  17. 28 10月, 2011 1 次提交
  19. 27 7月, 2011 1 次提交
    • A
      merge fchmod() and fchmodat() guts, kill ancient broken kludge · e57712eb
      由 Al Viro 提交于 
      The kludge in question is undocumented and doesn't work for 32bit
binaries on amd64, sparc64 and s390.  Passing (mode_t)-1 as
mode had (since 0.99.14v and contrary to behaviour of any
other Unix, prescriptions of POSIX, SuS and our own manpages)
was kinda-sorta no-op.  Note that any software relying on
that (and looking for examples shows none) would be visibly
broken on sparc64, where practically all userland is built
32bit.  No such complaints noticed...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      e57712eb
  21. 23 7月, 2011 1 次提交
  23. 21 3月, 2011 1 次提交
  25. 15 3月, 2011 2 次提交
    • A
      readlinkat(), fchownat() and fstatat() with empty relative pathnames · 65cfc672
      由 Al Viro 提交于 
      For readlinkat() we simply allow empty pathname; it will fail unless
we have dfd equal to O_PATH-opened symlink, so we are outside of
POSIX scope here.  For fchownat() and fstatat() we allow AT_EMPTY_PATH;
let the caller explicitly ask for such behaviour.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      65cfc672
    • A
      New kind of open files - "location only". · 1abf0c71
      由 Al Viro 提交于 
      New flag for open(2) - O_PATH.  Semantics:
	* pathname is resolved, but the file itself is _NOT_ opened
as far as filesystem is concerned.
	* almost all operations on the resulting descriptors shall
fail with -EBADF.  Exceptions are:
	1) operations on descriptors themselves (i.e.
		close(), dup(), dup2(), dup3(), fcntl(fd, F_DUPFD),
		fcntl(fd, F_DUPFD_CLOEXEC, ...), fcntl(fd, F_GETFD),
		fcntl(fd, F_SETFD, ...))
	2) fcntl(fd, F_GETFL), for a common non-destructive way to
		check if descriptor is open
	3) "dfd" arguments of ...at(2) syscalls, i.e. the starting
		points of pathname resolution
	* closing such descriptor does *NOT* affect dnotify or
posix locks.
	* permissions are checked as usual along the way to file;
no permission checks are applied to the file itself.  Of course,
giving such thing to syscall will result in permission checks (at
the moment it means checking that starting point of ....at() is
a directory and caller has exec permissions on it).

fget() and fget_light() return NULL on such descriptors; use of
fget_raw() and fget_raw_light() is needed to get them.  That protects
existing code from dealing with those things.

There are two things still missing (they come in the next commits):
one is handling of symlinks (right now we refuse to open them that
way; see the next commit for semantics related to those) and another
is descriptor passing via SCM_RIGHTS datagrams.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      1abf0c71
  27. 14 3月, 2011 2 次提交
    • A
      open-style analog of vfs_path_lookup() · 73d049a4
      由 Al Viro 提交于 
      new function: file_open_root(dentry, mnt, name, flags) opens the file
vfs_path_lookup would arrive to.

Note that name can be empty; in that case the usual requirement that
dentry should be a directory is lifted.

open-coded equivalents switched to it, may_open() got down exactly
one caller and became static.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      73d049a4
    • A
      switch do_filp_open() to struct open_flags · 47c805dc
      由 Al Viro 提交于 
      take calculation of open_flags by open(2) arguments into new helper
in fs/open.c, move filp_open() over there, have it and do_sys_open()
use that helper, switch exec.c callers of do_filp_open() to explicit
(and constant) struct open_flags.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      47c805dc
  29. 10 3月, 2011 1 次提交
  31. 12 2月, 2011 1 次提交
    • L
      Fix possible filp_cachep memory corruption · 2dab5974
      由 Linus Torvalds 提交于 
      In commit 31e6b01f ("fs: rcu-walk for path lookup") we started doing
path lookup using RCU, which then falls back to a careful non-RCU lookup
in case of problems (LOOKUP_REVAL).  So do_filp_open() has this "re-do
the lookup carefully" looping case.

However, that means that we must not release the open-intent file data
if we are going to loop around and use it once more!

Fix this by moving the release of the open-intent data to the function
that allocates it (do_filp_open() itself) rather than the helper
functions that can get called multiple times (finish_open() and
do_last()).  This makes the logic for the lifetime of that field much
more obvious, and avoids the possible double free.
Reported-by: NJ. R. Okajima <hooanon05@yahoo.co.jp>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2dab5974
  33. 10 2月, 2011 1 次提交
  35. 17 1月, 2011 1 次提交
    • C
      fallocate should be a file operation · 2fe17c10
      由 Christoph Hellwig 提交于 
      Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit.  Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes.  On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions.   Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.

This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      2fe17c10
  37. 13 1月, 2011 1 次提交
    • J
      fs: add hole punching to fallocate · 79124f18
      由 Josef Bacik 提交于 
      Hole punching has already been implemented by XFS and OCFS2, and has the
potential to be implemented on both BTRFS and EXT4 so we need a generic way to
get to this feature.  The simplest way in my mind is to add FALLOC_FL_PUNCH_HOLE
to fallocate() since it already looks like the normal fallocate() operation.
I've tested this patch with XFS and BTRFS to make sure XFS did what it's
supposed to do and that BTRFS failed like it was supposed to.  Thank you,
Signed-off-by: NJosef Bacik <josef@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      79124f18
  39. 29 10月, 2010 1 次提交
    • A
      fix open/umount race · d893f1bc
      由 Al Viro 提交于 
      nameidata_to_filp() drops nd->path or transfers it to opened
file.  In the former case it's a Bad Idea(tm) to do mnt_drop_write()
on nd->path.mnt, since we might race with umount and vfsmount in
question might be gone already.

Fix: don't drop it, then...  IOW, have nameidata_to_filp() grab nd->path
in case it transfers it to file and do path_drop() in callers.  After
they are through with accessing nd->path...
Reported-by: NMiklos Szeredi <miklos@szeredi.hu>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      d893f1bc
  41. 18 8月, 2010 1 次提交
  43. 11 8月, 2010 1 次提交
  45. 02 8月, 2010 2 次提交
  47. 28 7月, 2010 2 次提交
  49. 22 5月, 2010 1 次提交