linux/fs
Cyrill Gorcunov 5442e9fbd7 timerfd: Implement timerfd_ioctl method to restore timerfd_ctx::ticks, v3
The read() of timerfd files allows to fetch the number of timer ticks
while there is no way to set it back from userspace.

To restore the timer's state as it was at checkpoint moment we need
a path to bring @ticks back. Initially I thought about writing ticks
back via write() interface but it seems such API is somehow obscure.

Instead implement timerfd_ioctl() method with TFD_IOC_SET_TICKS
command which allows to adjust @ticks into non-zero value waking
up the waiters.

I wrapped code with CONFIG_CHECKPOINT_RESTORE which can be
dropped off if there users except c/r camp appear.

v2 (by akpm@):
 - Use define timerfd_ioctl NULL for non c/r config

v3:
 - Use copy_from_user for @ticks fetching since
   not all arch support get_user for 8 byte argument

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Andrey Vagin <avagin@openvz.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christopher Covington <cov@codeaurora.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Link: http://lkml.kernel.org/r/20140715215703.285617923@openvz.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-07-18 11:49:57 +02:00
..
9p Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
adfs write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
affs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
afs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
autofs4 autofs4: fix false positive compile error 2014-07-03 09:21:53 -07:00
befs fs/befs: kernel-doc fixes 2014-06-06 16:08:09 -07:00
bfs write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
btrfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-07-04 08:53:53 -07:00
cachefiles fs/cachefiles: replace kerror by pr_err 2014-06-06 16:08:14 -07:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2014-06-12 23:06:23 -07:00
cifs [CIFS] fix mount failure with broken pathnames when smb3 mount with mapchars option 2014-06-24 08:10:24 -05:00
coda coda: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
configfs fs/configfs: use pr_fmt 2014-06-04 16:53:53 -07:00
cramfs Major changes for 3.14 include support for the newly added ZERO_RANGE 2014-04-04 15:39:39 -07:00
debugfs Major changes for 3.14 include support for the newly added ZERO_RANGE 2014-04-04 15:39:39 -07:00
devpts fs/devpts/inode.c: convert printk to pr_foo() 2014-06-06 16:08:14 -07:00
dlm dlm: keep listening connection alive with sctp mode 2014-06-12 10:26:14 -05:00
ecryptfs write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
efivarfs fs/efivarfs/super.c: use static const for dentry_operations 2014-06-04 16:54:14 -07:00
efs fs/efs: convert printk(KERN_DEBUG to pr_debug 2014-06-04 16:54:21 -07:00
exofs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
exportfs fs/exportfs/expfs.c: kernel-doc warning fixes 2014-06-04 16:54:14 -07:00
ext2 ->splice_write() via ->write_iter() 2014-06-12 00:18:51 -04:00
ext3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
ext4 ext4: fix potential null pointer dereference in ext4_free_inode 2014-07-12 16:11:42 -04:00
f2fs f2fs: avoid to access NULL pointer in issue_flush_thread 2014-07-09 05:59:55 -07:00
fat Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
freevxfs Major changes for 3.14 include support for the newly added ZERO_RANGE 2014-04-04 15:39:39 -07:00
fscache fscache: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
fuse Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
gfs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
hfs write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
hfsplus Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
hostfs write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
hpfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
hppfs
hugetlbfs fs/hugetlbfs/inode.c: remove null test before kfree 2014-06-04 16:54:11 -07:00
isofs Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs 2014-04-07 17:59:17 -07:00
jbd fs/jbd/revoke.c: replace shift loop by ilog2 2014-05-21 10:26:13 +02:00
jbd2 ext4: disable synchronous transaction batching if max_batch_time==0 2014-07-05 19:18:22 -04:00
jffs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
jfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
kernfs Merge branch 'for-3.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2014-07-10 11:38:23 -07:00
lockd Merge branch 'for-3.16' of git://linux-nfs.org/~bfields/linux 2014-06-10 11:50:57 -07:00
logfs write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
minix write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
ncpfs fs/ncpfs/getopt.c: replace simple_strtoul by kstrtoul 2014-06-04 16:54:21 -07:00
nfs NFSv4: test SECINFO RPC_AUTH_GSS pseudoflavors for support 2014-06-24 18:46:58 -04:00
nfs_common
nfsd nfsd: Fix bad reserving space for encoding rdattr_error 2014-07-07 14:16:31 -04:00
nilfs2 write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
nls
notify inotify: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
ntfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
ocfs2 ocfs2/dlm: do not purge lockres that is queued for assert master 2014-06-23 16:47:45 -07:00
omfs write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
openpromfs fs: push sync_filesystem() down to the file system's remount_fs() 2014-03-13 10:14:33 -04:00
proc /proc/stat: convert to single_open_size() 2014-07-03 09:21:54 -07:00
pstore fs/pstore: logging clean-up 2014-06-06 16:08:13 -07:00
qnx4 fs: push sync_filesystem() down to the file system's remount_fs() 2014-03-13 10:14:33 -04:00
qnx6 fs: push sync_filesystem() down to the file system's remount_fs() 2014-03-13 10:14:33 -04:00
quota xfs: fix Q_XQUOTARM ioctl 2014-05-05 17:25:50 +10:00
ramfs ->splice_write() via ->write_iter() 2014-06-12 00:18:51 -04:00
reiserfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
romfs switch simple generic_file_aio_read() users to ->read_iter() 2014-05-06 17:37:55 -04:00
squashfs fs/squashfs/squashfs.h: replace pr_warning by pr_warn 2014-06-04 16:53:52 -07:00
sysfs kernfs: move the last knowledge of sysfs out from kernfs 2014-06-03 08:11:18 -07:00
sysv write_iter variants of {__,}generic_file_aio_write() 2014-05-06 17:38:00 -04:00
ubifs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
udf udf: switch to ->write_iter() 2014-05-06 17:39:36 -04:00
ufs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
xfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
Kconfig
Kconfig.binfmt
Makefile block: move ioprio.c from fs/ to block/ 2014-05-19 11:02:18 -06:00
aio.c aio: fix kernel memory disclosure in io_getevents() introduced in v3.10 2014-06-24 13:46:01 -04:00
anon_inodes.c vfs: Allocate anon_inode_inode in anon_inode_init() 2014-03-27 09:52:54 -07:00
attr.c fs,userns: Change inode_capable to capable_wrt_inode_uidgid 2014-06-10 13:57:22 -07:00
bad_inode.c
binfmt_aout.c
binfmt_elf.c Merge branch 'x86/vdso' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next 2014-06-05 08:05:29 -07:00
binfmt_elf_fdpic.c
binfmt_em86.c
binfmt_flat.c fs/binfmt_flat.c: make old_reloc() static 2014-06-04 16:54:21 -07:00
binfmt_misc.c binfmt_misc: add missing 'break' statement 2014-04-03 16:21:16 -07:00
binfmt_script.c
binfmt_som.c
block_dev.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
buffer.c mm: non-atomically mark page accessed during page cache allocation where possible 2014-06-04 16:54:10 -07:00
char_dev.c
compat.c locks: rename file-private locks to "open file description locks" 2014-04-22 08:23:58 -04:00
compat_binfmt_elf.c
compat_ioctl.c
coredump.c coredump: fix va_list corruption 2014-04-19 13:23:31 -07:00
dcache.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
dcookies.c
direct-io.c new helper: iov_iter_npages() 2014-05-06 17:32:52 -04:00
drop_caches.c fs: convert use of typedef ctl_table to struct ctl_table 2014-06-06 16:08:16 -07:00
eventfd.c
eventpoll.c epoll: fix use-after-free in eventpoll_release_file 2014-06-16 17:21:59 -10:00
exec.c perf: Differentiate exec() and non-exec() comm events 2014-06-06 07:56:22 +02:00
fcntl.c locks: rename file-private locks to "open file description locks" 2014-04-22 08:23:58 -04:00
fhandle.c
file.c fs/file.c: don't open-code kvfree() 2014-05-06 17:31:10 -04:00
file_table.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-06-12 10:30:18 -07:00
filesystems.c sys_sysfs: Add CONFIG_SYSFS_SYSCALL 2014-04-03 16:21:05 -07:00
fs-writeback.c One of the main highlights this time, is not the patches themselves 2014-04-04 14:49:16 -07:00
fs_struct.c
inode.c fs,userns: Change inode_capable to capable_wrt_inode_uidgid 2014-06-10 13:57:22 -07:00
internal.h
ioctl.c
libfs.c fs/libfs.c: add generic data flush to fsync 2014-06-04 16:53:55 -07:00
locks.c locks: set fl_owner for leases back to current->files 2014-06-10 12:29:05 -04:00
mbcache.c fs/mbcache: replace __builtin_log2() with ilog2() 2014-06-25 22:08:29 -04:00
mount.h reduce m_start() cost... 2014-04-01 23:19:09 -04:00
mpage.c fs/block_dev.c: add bdev_read_page() and bdev_write_page() 2014-06-04 16:54:02 -07:00
namei.c fs,userns: Change inode_capable to capable_wrt_inode_uidgid 2014-06-10 13:57:22 -07:00
namespace.c VFS: Make delayed_free() call free_vfsmnt() 2014-04-01 23:19:18 -04:00
no-block.c
open.c new methods: ->read_iter() and ->write_iter() 2014-05-06 17:36:00 -04:00
pipe.c new helper: copy_page_from_iter() 2014-05-06 17:39:42 -04:00
pnode.c smarter propagate_mnt() 2014-04-01 23:19:08 -04:00
pnode.h smarter propagate_mnt() 2014-04-01 23:19:08 -04:00
posix_acl.c posix_acl: handle NULL ACL in posix_acl_equiv_mode 2014-05-06 13:58:42 -04:00
proc_namespace.c reduce m_start() cost... 2014-04-01 23:19:09 -04:00
read_write.c switch simple generic_file_aio_read() users to ->read_iter() 2014-05-06 17:37:55 -04:00
readdir.c fanotify: create FAN_ACCESS event for readdir 2014-06-04 16:53:52 -07:00
select.c
seq_file.c fs/seq_file: fallback to vmalloc allocation 2014-07-03 09:21:54 -07:00
signalfd.c
splice.c Merge commit '9f12600fe425bc28f0ccba034a77783c09c15af4' into for-linus 2014-06-12 00:28:09 -04:00
stack.c
stat.c
statfs.c
super.c fs/superblock: avoid locking counting inodes and dentries before reclaiming them 2014-06-04 16:54:11 -07:00
sync.c
timerfd.c timerfd: Implement timerfd_ioctl method to restore timerfd_ctx::ticks, v3 2014-07-18 11:49:57 +02:00
utimes.c
xattr.c