->atomic_open() calling conventions are nasty; we have
two bits of state ("has file gotten past ->open()" and "have
we created a new file here") passed by reference, with rather
brittle logics in the callers. In some error cases do_last()
et.al. end up doing a full-blow fput() (and destroying the
struct file they've got), in some they leave that work (a
trimmed-down subset of it, at that) to path_openat(), with
the aforementioned state affecting what's going on.
It would be much easier if we stored the "has the
damn thing been past ->open()" (i.e. does it need fput()
or put_filp()) in file->f_mode. It doesn't take a lot
of massage to do that - mostly it's a matter of leaving
all struct file freeing in error cases to path_openat()
itself and preventing the wipeout of all ->f_mode bits
in do_dentry_open(). Moreover, we can store the "has it
been created" in the same ->f_mode, killing the 'int *opened'
mess completely. The same series gets O_DIRECT checks
properly centralized in do_dentry_open(), BTW.
Other fun stuff possible (but not done yet) is
unification of put_filp() and fput() and hopefully more
simple rules regarding those. Need to sort out some
things about pipe and ia64 perfmon first, though...
It's still a work-in-progress; what I've got right
now is in vfs.git#work.open;
current shortlog:
Al Viro (13):
drm_mode_create_lease_ioctl(): switch to filp_clone_open()
rename filp_clone_open() to file_clone_open()
introduce FMODE_OPENED
get rid of 'opened' argument of finish_open()
pull fput() on late failures into path_openat()
switch all remaining checks for FILE_OPENED to FMODE_OPENED
now we can fold open_check_o_direct() into do_dentry_open()
__gfs2_lookup(), nfs_finish_open() and fuse_create_open() don't need 'opened'
introduce FMODE_CREATED and switch to it
IMA: don't propagate opened through the entire thing
gfs2_create_inode() doesn't need 'opened' anymore
get rid of 'opened' argument of ->atomic_open()
get rid of 'opened' in path_openat() and the helpers downstream
diffstat:
arch/ia64/kernel/perfmon.c | 1 +
drivers/gpu/drm/drm_lease.c | 16 +-------------
drivers/misc/cxl/api.c | 2 +-
drivers/staging/lustre/lustre/llite/namei.c | 11 +++++-----
fs/9p/vfs_inode.c | 7 +++---
fs/9p/vfs_inode_dotl.c | 7 +++---
fs/aio.c | 3 ++-
fs/anon_inodes.c | 2 +-
fs/bad_inode.c | 2 +-
fs/binfmt_misc.c | 2 +-
fs/ceph/file.c | 7 +++---
fs/ceph/super.h | 3 +--
fs/cifs/cifsfs.h | 3 +--
fs/cifs/dir.c | 7 +++---
fs/fuse/dir.c | 10 ++++-----
fs/gfs2/inode.c | 32 +++++++++++++--------------
fs/hugetlbfs/inode.c | 2 +-
fs/internal.h | 2 --
fs/namei.c | 82 ++++++++++++++++++++++++++++------------------------------------------
fs/nfs/dir.c | 14 ++++++------
fs/nfs/nfs4_fs.h | 2 +-
fs/nfs/nfs4proc.c | 2 +-
fs/nfsd/vfs.c | 2 +-
fs/open.c | 48 +++++++++++++++--------------------------
fs/pipe.c | 2 ++
include/linux/fs.h | 10 ++++++---
include/linux/ima.h | 4 ++--
ipc/shm.c | 2 +-
mm/shmem.c | 2 +-
net/socket.c | 2 +-
security/integrity/ima/ima.h | 4 ++--
security/integrity/ima/ima_appraise.c | 4 ++--
security/integrity/ima/ima_main.c | 16 +++++++-------
33 files changed, 135 insertions(+), 180 deletions(-)
and it's been only slightly build-tested. Review and comments
would be welcome.
