09 Jan, 2012
1 commit
-
devpts_kill_sb() is called even if devpts_fill_super() fails;
we should not do that kfree() in the latter, especially not
with ->s_fs_info left pointing to freed object. Double kfree()
is a Bad Thing(tm)...Signed-off-by: Al Viro
07 Jan, 2012
1 commit
-
Signed-off-by: Al Viro
02 Nov, 2011
2 commits
-
Replace remaining direct i_nlink updates with a new set_nlink()
updater function.Signed-off-by: Miklos Szeredi
Tested-by: Toshiyuki Okajima
Signed-off-by: Christoph Hellwig -
Replace direct i_nlink updates with the respective updater function
(inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count).Signed-off-by: Miklos Szeredi
23 Mar, 2011
1 commit
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d_alloc_name return NULL in case error, but we expect errno in
devpts_pty_new.Addresses http://bugzilla.openvz.org/show_bug.cgi?id=1758
Signed-off-by: Andrey Vagin
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
21 Mar, 2011
1 commit
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In this case nobody can open a slave point, so will be better return
from devpts_pty_new()Now we should not check error code from d_find_alias() in
devpts_pty_kill(), because the dentry exists all times.Signed-off-by: Andrey Vagin
Signed-off-by: Al Viro
29 Oct, 2010
1 commit
-
Signed-off-by: Al Viro
22 May, 2010
1 commit
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postpone simple_set_mnt() until we know we won't fail.
Signed-off-by: Al Viro
30 Mar, 2010
1 commit
-
…it slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
12 Dec, 2009
1 commit
-
devpts_get_tty() assumes that the inode passed in is associated with a valid
pty. But if the only reference to the pty is via a bind-mount, the inode
passed to devpts_get_tty() while valid, would refer to a pty that no longer
exists.With a lot of debug effort, Grzegorz Nosek developed a small program (see
below) to reproduce a crash on recent kernels. This crash is a regression
introduced by the commit:commit 527b3e4773628b30d03323a2cb5fb0d84441990f
Author: Sukadev Bhattiprolu
Date: Mon Oct 13 10:43:08 2008 +0100To fix, ensure that the dentry associated with the inode has not yet been
deleted/unhashed by devpts_pty_kill().See also:
https://lists.linux-foundation.org/pipermail/containers/2009-July/019273.htmltty-bug.c:
#define _GNU_SOURCE
#include
#include
#include
#include
#include
#include
#include#include
void dummy(int sig)
{
}static int child(void *unused)
{
int fd;signal(SIGINT, dummy); signal(SIGHUP, dummy);
pause(); /* cheesy synchronisation to wait for /dev/pts/0 to appear */mount("/dev/pts/0", "/dev/console", NULL, MS_BIND, NULL);
sleep(2);fd = open("/dev/console", O_RDWR);
dup(0); dup(0);
write(1, "Hello world!\n", sizeof("Hello world!\n")-1);
return 0;
}int main(void)
{
pid_t pid;
char *stack;stack = malloc(16384);
pid = clone(child, stack+16384, CLONE_NEWNS|SIGCHLD, NULL);open("/dev/ptmx", O_RDWR|O_NOCTTY|O_NONBLOCK);
unlockpt(fd); grantpt(fd);
sleep(2);
kill(pid, SIGHUP);
sleep(1);
return 0; /* exit before child opens /dev/console */
}Reported-by: Grzegorz Nosek
Signed-off-by: Sukadev Bhattiprolu
Tested-by: Serge Hallyn
Cc: stable
Signed-off-by: Greg Kroah-Hartman
23 Sep, 2009
1 commit
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Move various magic-number definitions into magic.h.
Signed-off-by: Nick Black
Acked-by: Pekka Enberg
Cc: Al Viro
Cc: "David S. Miller"
Cc: Casey Schaufler
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
24 Jun, 2009
1 commit
-
These days, the devpts filesystem is closely integrated with the pty
memory management, and cannot be built as a module, even less removed
from the kernel. Accordingly, remove all module-related stuff from
this filesystem.[ v2: only remove code that's actually dead ]
Signed-off-by: H. Peter Anvin
Signed-off-by: Al Viro
11 Jun, 2009
1 commit
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Closes-bug: http://bugzilla.kernel.org/show_bug.cgi?id=13429
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds
15 May, 2009
1 commit
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devpts_get_sb() calls memset(0) to clear mount options and calls
parse_mount_options() if user specified any mount options.The memset(0) is bogus since the 'mode' and 'ptmxmode' options are
non-zero by default. parse_mount_options() restores options to default
anyway and can properly deal with NULL mount options.So in devpts_get_sb() remove memset(0) and call parse_mount_options() even
for NULL mount options.Bug reported by Eric Paris: http://lkml.org/lkml/2009/5/7/448.
Signed-off-by: Sukadev Bhattiprolu
Tested-by: Marc Dionne
Reported-by: Eric Paris
Cc: Christoph Hellwig
Cc: Alan Cox
Acked-by: Serge Hallyn
Cc: Al Viro
Cc: "Rafael J. Wysocki"
Reviewed-by: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 May, 2009
1 commit
-
Signed-off-by: Al Viro
28 Mar, 2009
7 commits
-
new_pts_mount() (including the get_sb_nodev()), shares a lot of code
with init_pts_mount(). The only difference between them is the 'test-super'
function passed into sget().Move all common code into devpts_get_sb() and remove the new_pts_mount() and
init_pts_mount() functions,Changelog[v3]:
[Serge Hallyn]: Remove unnecessary printk()s
Changelog[v2]:
(Christoph Hellwig): Merge code in 'do_pts_mount()' into devpts_get_sb()Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Tested-by: Serge Hallyn
Signed-off-by: Al Viro -
With mknod_ptmx() moved to devpts_get_sb(), init_pts_mount() becomes
a wrapper around get_init_pts_sb(). Remove get_init_pts_sb() and
fold code into init_pts_mount().Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Signed-off-by: Al Viro -
We create 'ptmx' node in both single-instance and multiple-instance
mounts. So devpts_get_sb() can call mknod_ptmx() once rather than
have both modes calling mknod_ptmx() separately.Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Signed-off-by: Al Viro -
Since all the mount option parsing is done in devpts, we could do it
just once and pass it around in devpts functions and eventually store
it in the super block.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Al Viro -
On remount, devpts fs only needs to parse the mount options. Users cannot
directly create/dirty files in /dev/pts so the MS_RDONLY flag and
shrinking the dcache does not really apply to devpts.So effectively on remount, devpts only parses the mount options and updates
these options in its super block. As such, we could replace do_remount_sb()
call with a direct parse_mount_options().Doing so enables subsequent patches to avoid parsing the mount options twice
and simplify the code.Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Signed-off-by: Al Viro -
simple_set_mnt() is defined as returning 'int' but always returns 0.
Callers assume simple_set_mnt() never fails and don't properly cleanup if
it were to _ever_ fail. For instance, get_sb_single() and get_sb_nodev()
should:up_write(sb->s_unmount);
deactivate_super(sb);if simple_set_mnt() fails.
Since simple_set_mnt() never fails, would be cleaner if it did not
return anything.[akpm@linux-foundation.org: fix build]
Signed-off-by: Sukadev Bhattiprolu
Acked-by: Serge Hallyn
Cc: Al Viro
Cc: Christoph Hellwig
Signed-off-by: Andrew Morton
Signed-off-by: Al Viro -
We should drop the ->s_umount mutex if an error occurs after the
sget()/grab_super() call. This was introduced when adding support
for multiple instances of devpts and noticed during a code review/reorg.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Al Viro
11 Mar, 2009
1 commit
-
Very annoying when working with containters.
Signed-off-by: Alexey Dobriyan
Cc: Alan Cox
Cc: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
06 Jan, 2009
1 commit
-
... and don't bother in callers. Don't bother with zeroing i_blocks,
while we are at it - it's already been zeroed.i_mode is not worth the effort; it has no common default value.
Signed-off-by: Al Viro
03 Jan, 2009
10 commits
-
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.Signed-off-by: David Howells
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
fs/devpts/inode.c:324: warning: 'compare_init_pts_sb' defined but not used
Signed-off-by: Andrew Morton
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
Just nail the oddments now while this code is being touched
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
To support containers, allow multiple instances of devpts filesystem, such
that indices of ptys allocated in one instance are independent of ptys
allocated in other instances of devpts.But to preserve backward compatibility, enable this support for multiple
instances only if:- CONFIG_DEVPTS_MULTIPLE_INSTANCES is set to Y, and
- '-o newinstance' mount option is specified while mounting devptsTo use multi-instance mount, a container startup script could:
$ ns_exec -cm /bin/bash
$ umount /dev/pts
$ mount -t devpts -o newinstance lxcpts /dev/pts
$ mount -o bind /dev/pts/ptmx /dev/ptmx
$ /usr/sbin/sshd -p 1234where 'ns_exec -cm /bin/bash' is calls clone() with CLONE_NEWNS flag and execs
/bin/bash in the child process. A pty created by the sshd is not visible in
the original mount of /dev/pts.USER-SPACE-IMPACT:
- See Documentation/fs/devpts.txt (included in next patch) for user-
space impact in multi-instance and mixed-mode operation.
TODO:
- Update mount(8), pts(4) man pages. Highlight impact of not
redirecting /dev/ptmx to /dev/pts/ptmx after a multi-instance mount.Changelog[v6]:
- [Dave Hansen] Use new get_init_pts_sb() interface
- [Serge Hallyn] Don't bother displaying 'newinstance' in show_options
- [Serge Hallyn] Use macros (PARSE_REMOUNT/PARSE_MOUNT) instead of 0/1.
- [Serge Hallyn] Check error return from get_sb_single() (now
get_init_pts_sb())
- devpts_pty_kill(): don't dput error dentriesChangelog[v5]:
- Move get_sb_ref() definition to earlier patch
- Move usage info to Documentation/filesystems/devpts.txt (next patch)
- Make ptmx node even in init_pts_ns, now that default mode is 0000
(defined in earlier patch, enabled here).
- Cache ptmx dentry and use to update mode during remount
(defined in earlier patch, enabled here).
- Bugfix: explicitly ignore newinstance on remount (if newinstance was
specified on remount of initial mount, it would be ignored but
/proc/mounts would imply that the option was set)Changelog[v4]:
- Update patch description to address H. Peter Anvin's comments
- Consolidate multi-instance mode code under new config token,
CONFIG_DEVPTS_MULTIPLE_INSTANCE.
- Move usage-details from patch description to
Documentation/fs/devpts.txtChangelog[v3]:
- Rename new mount option to 'newinstance'
- Create ptmx nodes only in 'newinstance' mounts
- Bugfix: parse_mount_options() modifies @data but since we need to
parse the @data twice (once in devpts_get_sb() and once during
do_remount_sb()), parse a local copy of @data in devpts_get_sb().
(restructured code in devpts_get_sb() to fix this)Changelog[v2]:
- Support both single-mount and multiple-mount semantics and
provide '-onewmnt' option to select the semantics.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
See comments in the function header for details. The new interface will
be used in a follow-on patch.Changelog [v2]:
[Dave Hansen] Replace get_sb_ref() in fs/super.c with get_init_pts_sb()
and make the new interface private to devptsSigned-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
/dev/ptmx is closely tied to the devpts filesystem. An open of /dev/ptmx,
allocates the next pty index and the associated device shows up in the
devpts fs as /dev/pts/n.Wih multiple instancs of devpts filesystem, during an open of /dev/ptmx
we would be unable to determine which instance of the devpts is being
accessed.So we move the 'ptmx' node into /dev/pts and use the inode of the 'ptmx'
node to identify the superblock and hence the devpts instance. This patch
adds ability for the kernel to internally create the [ptmx, c, 5:2] device
when mounting devpts filesystem. Since the ptmx node in devpts is new and
may surprise some userspace scripts, the default permissions for the new
node is 0000. These permissions can be changed either using chmod or by
remounting with the new '-o ptmxmode=0666' mount option.Changelog[v5]:
- [Serge Hallyn bugfix]: Letting new_inode() assign inode number to
ptmx can collide with hand-assigning inode numbers to ptys. So,
hand-assign specific inode number to ptmx node also.
- [Serge Hallyn]: Maybe safer to grab root dentry mutex while creating
ptmx node
- [Bugfix with Serge Hallyn] Replace lookup_one_len() in mknod_ptmx()
wih d_alloc_name() (lookup during ->get_sb() locks up system). To
simplify patchset, fold the ptmx_dentry patch into this.Changelog[v4]:
- Change default permissions of pts/ptmx node to 0000.
- Move code for ptmxmode under #ifdef CONFIG_DEVPTS_MULTIPLE_INSTANCES.Changelog[v3]:
- Rename ptmx_mode to ptmxmode (for consistency with 'newinstance')Changelog[v2]:
- [H. Peter Anvin] Remove mknod() system call support and create the
ptmx node internally.Changelog[v1]:
- Earlier version of this patch enabled creating /dev/pts/tty as
well. As pointed out by Al Viro and H. Peter Anvin, that is not
really necessary.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
Move code to parse mount options into a separate function so it can
(later) be shared between mount and remount operations.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
With support for multiple mounts of devpts, the 'config' structure really
represents per-mount options rather than config parameters. Rename 'config'
structure to 'pts_mount_opts' and store it in the super-block.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
To enable multiple mounts of devpts, 'allocated_ptys' must be a per-mount
variable rather than a global variable. Move 'allocated_ptys' into the
super_block's s_fs_info.Changelog[v2]:
Define and use DEVPTS_SB() wrapper.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
Remove the 'devpts_root' global variable and find the root dentry using
the super_block. The super-block can be found from the device inode, using
the new wrapper, pts_sb_from_inode().Changelog: This patch is based on an earlier patchset from Serge Hallyn
and Matt Helsley.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds
14 Nov, 2008
1 commit
-
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.Signed-off-by: David Howells
Reviewed-by: James Morris
Acked-by: Serge Hallyn
Signed-off-by: James Morris
14 Oct, 2008
5 commits
-
This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.This was posted for review some time ago and I believe its been in -mm
since then.Signed-off-by: Steven Whitehouse
Cc: Alexander Viro
Signed-off-by: Linus Torvalds -
When creating a new pty, save the pty's inode in the tty->driver_data.
Use this inode in pty_kill() to identify the devpts instance. Since
we now have the inode for the pty, we can skip get_node() lookup and
remove the unused get_node().TODO:
- check if the mutex_lock is needed in pty_kill().Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
devpts_pty_new() is called when setting up a new pty and would not
will not have an existing dentry or inode for the pty. So don't bother
looking for an existing dentry - just create a new one.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
As pointed out by H. Peter Anvin, since the inode for the pty is known,
we don't need to look it up.Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds -
Pass-in 'inode' or 'tty' parameter to devpts interfaces. With multiple
devpts instances, these parameters will be used in subsequent patches
to identify the instance of devpts mounted. The parameters also help
simplify devpts implementation.Changelog[v3]:
- minor changes due to merge with ttydev updates
- rename parameters to emphasize they are ptmx or pts inodes
- pass-in tty_struct * to devpts_pty_kill() (this will help
cleanup the get_node() call in a subsequent patch)Signed-off-by: Sukadev Bhattiprolu
Signed-off-by: Alan Cox
Signed-off-by: Linus Torvalds
