Commit Graph

400563 Commits

Author SHA1 Message Date
Al Viro
22a8cb8248 new helper: dump_align()
dump_skip to given alignment...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:27 -05:00
Al Viro
7b1f4020d0 spufs: get rid of dump_emit() wrappers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:27 -05:00
Al Viro
9b56d54380 dump_skip(): dump_seek() replacement taking coredump_params
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:26 -05:00
Al Viro
2507a4fbd4 make dump_emit() use vfs_write() instead of banging at ->f_op->write directly
... and deal with short writes properly - the output might be to pipe, after
all; as it is, e.g. no-MMU case of elf_fdpic coredump can write a whole lot
more than a page worth of data at one call.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:26 -05:00
Al Viro
1ad67015e6 binfmt_elf: count notes towards coredump limit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:25 -05:00
Al Viro
43a5d548eb aout: switch to dump_emit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:25 -05:00
Al Viro
cdc3d5627d switch elf_coredump_extra_notes_write() to dump_emit()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:24 -05:00
Al Viro
e6c1baa9b5 convert the rest of binfmt_elf_fdpic to dump_emit()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:24 -05:00
Al Viro
13046ece96 binfmt_elf: convert writing actual dump pages to dump_emit()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:24 -05:00
Al Viro
aa3e7eaf0a switch elf_core_write_extra_data() to dump_emit()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:23 -05:00
Al Viro
506f21c556 switch elf_core_write_extra_phdrs() to dump_emit()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:23 -05:00
Al Viro
ecc8c7725e new helper: dump_emit()
dump_write() analog, takes core_dump_params instead of file,
keeps track of the amount written in cprm->written and checks for
cprm->limit.  Start using it in binfmt_elf.c...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:22 -05:00
Al Viro
7d2f551f6d restore 32bit aout coredump
just getting rid of bitrot

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:22 -05:00
Al Viro
0f6ed63b17 no need to keep brlock macros anymore...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:21 -05:00
Al Viro
11d100d9a2 coda_revalidate_inode(): switch to passing inode...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:21 -05:00
Al Viro
b61625d245 fold __d_shrink() into its only remaining caller
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:21 -05:00
Al Viro
eee5cc2702 get rid of s_files and files_lock
The only thing we need it for is alt-sysrq-r (emergency remount r/o)
and these days we can do just as well without going through the
list of files.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:20 -05:00
Al Viro
8b61e74ffc get rid of {lock,unlock}_rcu_walk()
those have become aliases for rcu_read_{lock,unlock}()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:20 -05:00
Al Viro
48a066e72d RCU'd vfsmounts
* RCU-delayed freeing of vfsmounts
* vfsmount_lock replaced with a seqlock (mount_lock)
* sequence number from mount_lock is stored in nameidata->m_seq and
used when we exit RCU mode
* new vfsmount flag - MNT_SYNC_UMOUNT.  Set by umount_tree() when its
caller knows that vfsmount will have no surviving references.
* synchronize_rcu() done between unlocking namespace_sem in namespace_unlock()
and doing pending mntput().
* new helper: legitimize_mnt(mnt, seq).  Checks the mount_lock sequence
number against seq, then grabs reference to mnt.  Then it rechecks mount_lock
again to close the race and either returns success or drops the reference it
has acquired.  The subtle point is that in case of MNT_SYNC_UMOUNT we can
simply decrement the refcount and sod off - aforementioned synchronize_rcu()
makes sure that final mntput() won't come until we leave RCU mode.  We need
that, since we don't want to end up with some lazy pathwalk racing with
umount() and stealing the final mntput() from it - caller of umount() may
expect it to return only once the fs is shut down and we don't want to break
that.  In other cases (i.e. with MNT_SYNC_UMOUNT absent) we have to do
full-blown mntput() in case of mount_lock sequence number mismatch happening
just as we'd grabbed the reference, but in those cases we won't be stealing
the final mntput() from anything that would care.
* mntput_no_expire() doesn't lock anything on the fast path now.  Incidentally,
SMP and UP cases are handled the same way - no ifdefs there.
* normal pathname resolution does *not* do any writes to mount_lock.  It does,
of course, bump the refcounts of vfsmount and dentry in the very end, but that's
it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:19 -05:00
Al Viro
42c326082d switch shrink_dcache_for_umount() to use of d_walk()
we have too many iterators in fs/dcache.c...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:06 -05:00
Al Viro
dd3e2c55a4 fuse: rcu-delay freeing fuse_conn
makes ->permission() and ->d_revalidate() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:45:13 -04:00
Al Viro
1adfcb03e3 pid_namespace: make freeing struct pid_namespace rcu-delayed
makes procfs ->premission() instances safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:29 -04:00
Al Viro
1dcddd4abd ncpfs: rcu-delay unload_nls() and freeing ncp_server
makes ->d_hash() and ->d_compare() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:28 -04:00
Al Viro
cac45b062c fat: rcu-delay unloading nls and freeing sbi
makes ->d_hash() and ->d_compare() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:28 -04:00
Al Viro
2e32cf5ef2 cifs: rcu-delay unload_nls() and freeing sbi
makes ->d_hash(), ->d_compare() and ->permission() safety in RCU mode
independent from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:27 -04:00
Al Viro
baa40671d3 autofs4: make freeing sbi rcu-delayed
makes ->d_managed() safety in RCU mode independent from vfsmount_lock

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:27 -04:00
Al Viro
2d1d9b5b5c adfs: delayed freeing of sbi
makes ->d_hash() and ->d_compare() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:27 -04:00
Al Viro
30687e0a47 hpfs: make freeing sbi and codetables rcu-delayed
makes ->d_hash() and ->d_compare() safety in RCU mode independent
from vfsmount_lock

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:26 -04:00
Al Viro
e2fec7c355 make freeing super_block rcu-delayed
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:43:26 -04:00
Miklos Szeredi
b70a80e7a1 vfs: introduce d_instantiate_no_diralias()
...which just returns -EBUSY if a directory alias would be created.

This is to be used by fuse mkdir to make sure that a buggy or malicious
userspace filesystem doesn't do anything nasty.  Previously fuse used a
private mutex for this purpose, which can now go away.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-24 23:41:37 -04:00
Al Viro
94e92a6e77 move taking vfsmount_lock down into prepend_path()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:35:01 -04:00
Al Viro
474279dc0f split __lookup_mnt() in two functions
Instead of passing the direction as argument (and checking it on every
step through the hash chain), just have separate __lookup_mnt() and
__lookup_mnt_last().  And use the standard iterators...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:35:00 -04:00
Al Viro
7eb5e88269 uninline destroy_super(), consolidate alloc_super()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:35:00 -04:00
Al Viro
966c1f75f8 isofs: don't pass dentry to isofs_hash{i,}_common()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:59 -04:00
Al Viro
719ea2fbb5 new helpers: lock_mount_hash/unlock_mount_hash
aka br_write_{lock,unlock} of vfsmount_lock.  Inlines in fs/mount.h,
vfsmount_lock extern moved over there as well.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:59 -04:00
Al Viro
aab407fc5c don't bother with vfsmount_lock in mounts_poll()
wake_up_interruptible/poll_wait provide sufficient barriers;
just use ACCESS_ONCE() to fetch ns->event and that's it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:59 -04:00
Al Viro
aba809cf09 namespace.c: get rid of mnt_ghosts
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:58 -04:00
Al Viro
9559f68915 fold dup_mnt_ns() into its only surviving caller
should've been done 6 years ago...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:58 -04:00
Al Viro
f6b742d869 mnt_set_expiry() doesn't need vfsmount_lock
->mnt_expire is protected by namespace_sem

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:57 -04:00
Al Viro
22a7919299 finish_automount() doesn't need vfsmount_lock for removal from expiry list
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:57 -04:00
Al Viro
085e83ff0c fs/namespace.c: bury long-dead define
MNT_WRITER_UNDERFLOW_LIMIT has been missed 4 years ago when it became unused.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:57 -04:00
Al Viro
649a795aff fold mntfree() into mntput_no_expire()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:56 -04:00
Al Viro
6339dab869 do_remount(): pull touch_mnt_namespace() up
... and don't bother with dropping and regaining vfsmount_lock

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:56 -04:00
Al Viro
aa7a574d0c dup_mnt_ns(): get rid of pointless grabbing of vfsmount_lock
mnt_list is protected by namespace_sem, not vfsmount_lock

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:55 -04:00
Al Viro
44bb4385ce fs_is_visible only needs namespace_sem held shared
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:55 -04:00
Al Viro
59aa0da8e2 initialize namespace_sem statically
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:54 -04:00
Al Viro
72c2d53192 file->f_op is never NULL...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:54 -04:00
Al Viro
22bd002ee7 rtl8188eu: remove dead code
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:54 -04:00
Al Viro
79b185dd1a dmxdev: get rid of pointless clearing ->f_op
nobody else will see that struct file after return from ->release()
anyway; just leave ->f_op as is and let __fput() do that fops_put().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:53 -04:00
Al Viro
e84f9e57b9 consolidate the reassignments of ->f_op in ->open() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:53 -04:00