10 Jul, 2013
10 commits
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We can now drop the msg_lock and msg_lock_check functions along with a
bogus comment introduced previously in semctl_down.Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
do_msgrcv() is the last msg queue function that abuses the ipc lock Take
it only when needed when actually updating msq.Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Tested-by: Sedat Dilek
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
do_msgsnd() is another function that does too many things with the ipc
object lock acquired. Take it only when needed when actually updating
msq.Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
While the INFO cmd doesn't take the ipc lock, the STAT commands do
acquire it unnecessarily. We can do the permissions and security checks
only holding the rcu lock.This function now mimics semctl_nolock().
Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add msq_obtain_object() and msq_obtain_object_check(), which will allow
us to get the ipc object without acquiring the lock. Just as with
semaphores, these functions are basically wrappers around
ipc_obtain_object*().Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Similar to semctl, when calling msgctl, the *_INFO and *_STAT commands
can be performed without acquiring the ipc object.Add a msgctl_nolock() function and move the logic of *_INFO and *_STAT
out of msgctl(). This change still takes the lock and it will be
properly lockless in the next patchSigned-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Instead of holding the ipc lock for the entire function, use the
ipcctl_pre_down_nolock and only acquire the lock for specific commands:
RMID and SET.Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This function currently acquires both the rw_mutex and the rcu lock on
successful lookups, leaving the callers to explicitly unlock them,
creating another two level locking situation.Make the callers (including those that still use ipcctl_pre_down())
explicitly lock and unlock the rwsem and rcu lock.Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Signed-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patchset continues the work that began in the sysv ipc semaphore
scaling series, seehttps://lkml.org/lkml/2013/3/20/546
Just like semaphores used to be, sysv shared memory and msg queues also
abuse the ipc lock, unnecessarily holding it for operations such as
permission and security checks.This patchset mostly deals with mqueues, and while shared mem can be
done in a very similar way, I want to get these patches out in the open
first. It also does some pending cleanups, mostly focused on the two
level locking we have in ipc code, taking care of ipc_addid() and
ipcctl_pre_down_nolock() - yes there are still functions that need to be
updated as well.This patch:
Make all callers explicitly take and release the RCU read lock.
This addresses the two level locking seen in newary(), newseg() and
newqueue(). For the last two, explicitly unlock the ipc object and the
rcu lock, instead of calling the custom shm_unlock and msg_unlock
functions. The next patch will deal with the open coded locking for
->perm.lockSigned-off-by: Davidlohr Bueso
Cc: Andi Kleen
Cc: Rik van Riel
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 May, 2013
6 commits
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The ipc/msg.c code does its list operations by hand and it open-codes the
accesses, instead of using for_each_entry_[safe].Signed-off-by: Nikola Pajkovsky
Cc: Stanislav Kinsbursky
Cc: "Eric W. Biederman"
Cc: Peter Hurley
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Introduce finer grained locking for semtimedop, to handle the common case
of a program wanting to manipulate one semaphore from an array with
multiple semaphores.If the call is a semop manipulating just one semaphore in an array with
multiple semaphores, only take the lock for that semaphore itself.If the call needs to manipulate multiple semaphores, or another caller is
in a transaction that manipulates multiple semaphores, the sem_array lock
is taken, as well as all the locks for the individual semaphores.On a 24 CPU system, performance numbers with the semop-multi
test with N threads and N semaphores, look like this:vanilla Davidlohr's Davidlohr's + Davidlohr's +
threads patches rwlock patches v3 patches
10 610652 726325 1783589 2142206
20 341570 365699 1520453 1977878
30 288102 307037 1498167 2037995
40 290714 305955 1612665 2256484
50 288620 312890 1733453 2650292
60 289987 306043 1649360 2388008
70 291298 306347 1723167 2717486
80 290948 305662 1729545 2763582
90 290996 306680 1736021 2757524
100 292243 306700 1773700 3059159[davidlohr.bueso@hp.com: do not call sem_lock when bogus sma]
[davidlohr.bueso@hp.com: make refcounter atomic]
Signed-off-by: Rik van Riel
Suggested-by: Linus Torvalds
Acked-by: Davidlohr Bueso
Cc: Chegu Vinod
Cc: Jason Low
Reviewed-by: Michel Lespinasse
Cc: Peter Hurley
Cc: Stanislav Kinsbursky
Tested-by: Emmanuel Benisty
Tested-by: Sedat Dilek
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
[fengguang.wu@intel.com: find_msg can be static]
Signed-off-by: Peter Hurley
Cc: Fengguang Wu
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Signed-off-by: Peter Hurley
Acked-by: Stanislav Kinsbursky
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Teach the helper routines about MSG_COPY so that msgtyp is preserved as
the message number to copy.The security functions affected by this change were audited and no
additional changes are necessary.Signed-off-by: Peter Hurley
Acked-by: Stanislav Kinsbursky
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In preparation for refactoring the queue scan into a separate
function, relocate msg copying.Signed-off-by: Peter Hurley
Acked-by: Stanislav Kinsbursky
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
03 Apr, 2013
1 commit
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Make sure that msg pointer is set back to error value in case of
MSG_COPY flag is set and desired message to copy wasn't found. This
garantees that msg is either a error pointer or a copy address.Otherwise the last message in queue will be freed without unlinking from
the queue (which leads to memory corruption) and the dummy allocated
copy won't be released.Signed-off-by: Stanislav Kinsbursky
Signed-off-by: Linus Torvalds
09 Mar, 2013
1 commit
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When MSG_COPY is set, a duplicate message must be allocated for the copy
before locking the queue. However, the copy could not be larger than was
sent which is limited to msg_ctlmax.Signed-off-by: Peter Hurley
Acked-by: Stanislav Kinsbursky
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
05 Jan, 2013
7 commits
-
Signed-off-by: Stanislav Kinsbursky
Cc: "Eric W. Biederman"
Cc: James Morris
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Remove the redundant and confusing fill_copy(). Also add copy_msg()
check for error. In this case exit from the function have to be done
instead of break, because further code interprets any error as EAGAIN.Also define copy_msg() for the case when CONFIG_CHECKPOINT_RESTORE is
disabled.Signed-off-by: Stanislav Kinsbursky
Cc: "Eric W. Biederman"
Cc: James Morris
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This code works if CONFIG_CHECKPOINT_RESTORE is disabled.
[akpm@linux-foundation.org: remove __maybe_unused]
Signed-off-by: Stanislav Kinsbursky
Cc: "Eric W. Biederman"
Cc: James Morris
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Passing and checking of msgflg to free_copy() is redundant. This patch
sets copy to NULL on declaration instead and checks for non-NULL in
free_copy().Note: in case of copy allocation failure, error is returned immediately.
So no need to check for IS_ERR() in free_copy().Signed-off-by: Stanislav Kinsbursky
Cc: "Eric W. Biederman"
Cc: James Morris
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch is required for checkpoint/restore in userspace.
c/r requires some way to get all pending IPC messages without deleting
them from the queue (checkpoint can fail and in this case tasks will be
resumed, so queue have to be valid).To achive this, new operation flag MSG_COPY for sys_msgrcv() system call
was introduced. If this flag was specified, then mtype is interpreted as
number of the message to copy.If MSG_COPY is set, then kernel will allocate dummy message with passed
size, and then use new copy_msg() helper function to copy desired message
(instead of unlinking it from the queue).Notes:
1) Return -ENOSYS if MSG_COPY is specified, but
CONFIG_CHECKPOINT_RESTORE is not set.Signed-off-by: Stanislav Kinsbursky
Cc: Serge Hallyn
Cc: "Eric W. Biederman"
Cc: Pavel Emelyanov
Cc: Al Viro
Cc: KOSAKI Motohiro
Cc: Michael Kerrisk
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Move all message related manipulation into one function msg_fill().
Actually, two functions because of the compat one.[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Stanislav Kinsbursky
Cc: Serge Hallyn
Cc: "Eric W. Biederman"
Cc: Pavel Emelyanov
Cc: Al Viro
Cc: KOSAKI Motohiro
Cc: Michael Kerrisk
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This is a cleanup patch. The assignment is redundant.
Signed-off-by: Stanislav Kinsbursky
Cc: Serge Hallyn
Cc: "Eric W. Biederman"
Cc: Pavel Emelyanov
Cc: Al Viro
Cc: KOSAKI Motohiro
Cc: Michael Kerrisk
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Sep, 2012
1 commit
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- Store the ipc owner and creator with a kuid
- Store the ipc group and the crators group with a kgid.
- Add error handling to ipc_update_perms, allowing it to
fail if the uids and gids can not be converted to kuids
or kgids.
- Modify the proc files to display the ipc creator and
owner in the user namespace of the opener of the proc file.Signed-off-by: Eric W. Biederman
31 Mar, 2011
1 commit
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Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: Lucas De Marchi
24 Mar, 2011
1 commit
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CAP_IPC_OWNER and CAP_IPC_LOCK can be checked against current_user_ns(),
because the resource comes from current's own ipc namespace.setuid/setgid are to uids in own namespace, so again checks can be against
current_user_ns().Changelog:
Jan 11: Use task_ns_capable() in place of sched_capable().
Jan 11: Use nsown_capable() as suggested by Bastian Blank.
Jan 11: Clarify (hopefully) some logic in futex and sched.c
Feb 15: use ns_capable for ipc, not nsown_capable
Feb 23: let copy_ipcs handle setting ipc_ns->user_ns
Feb 23: pass ns down rather than taking it from current[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Serge E. Hallyn
Acked-by: "Eric W. Biederman"
Acked-by: Daniel Lezcano
Acked-by: David Howells
Cc: James Morris
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
25 May, 2010
1 commit
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- C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not
USHORT_MAX/SHORT_MAX/SHORT_MIN.- Make SHRT_MIN of type s16, not int, for consistency.
[akpm@linux-foundation.org: fix drivers/dma/timb_dma.c]
[akpm@linux-foundation.org: fix security/keys/keyring.c]
Signed-off-by: Alexey Dobriyan
Acked-by: WANG Cong
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
30 Mar, 2010
1 commit
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…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>
16 Dec, 2009
1 commit
-
We have apparently had a memory leak since
7ca7e564e049d8b350ec9d958ff25eaa24226352 "ipc: store ipcs into IDRs" in
2007. The idr of which 3 exist for each ipc namespace is never freed.This patch simply frees them when the ipcns is freed. I don't believe any
idr_remove() are done from rcu (and could therefore be delayed until after
this idr_destroy()), so the patch should be safe. Some quick testing
showed no harm, and the memory leak fixed.Caught by kmemleak.
Signed-off-by: Serge E. Hallyn
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Dec, 2009
1 commit
-
Commit a0d092f introduced the following warning:
ipc/msg.c: In function ?msgctl_down?:
ipc/msg.c:415: warning: ?msqid64? may be used uninitialized in this functionThe gcc warning in this case is actually bogus, as msqid64 is touched only
iff cmd == IPC_SET, and in such case, copy_msqid_from_user() initializes
it properly.Signed-off-by: Felipe Contreras
Signed-off-by: Jiri Kosina
14 Jan, 2009
1 commit
-
Signed-off-by: Heiko Carstens
07 Jun, 2008
1 commit
-
When posting:
[PATCH 1/8] Scaling msgmni to the amount of lowmem
(see http://lkml.org/lkml/2008/2/11/171), I have added a KERN_INFO message
that is output each time msgmni is recomputed.In http://lkml.org/lkml/2008/4/29/575 Tony Luck complained that this
message references an ipc namespace address that is useless.I first thought of using an audit_log instead of a printk, as suggested by
Serge Hallyn. But unfortunately, we do not have any other information
than the namespace address to provide here too. So I chose to move the
message and output it only at boot time, removing the reference to the
namespace.Signed-off-by: Nadia Derbey
Cc: Pierre Peiffer
Cc: Manfred Spraul
Acked-by: Tony Luck
Cc: "Serge E. Hallyn"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
29 Apr, 2008
6 commits
-
Add definitions of USHORT_MAX and others into kernel. ipc uses it and slub
implementation might also use it.[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Zhang Yanmin
Reviewed-by: Christoph Lameter
Cc: Nadia Derbey
Cc: "Pierre Peiffer"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
semctl_down(), msgctl_down() and shmctl_down() are used to handle the same set
of commands for each kind of IPC. They all start to do the same job (they
retrieve the ipc and do some permission checks) before handling the commands
on their own.This patch proposes to consolidate this by moving these same pieces of code
into one common function called ipcctl_pre_down().It simplifies a little these xxxctl_down() functions and increases a little
the maintainability.Signed-off-by: Pierre Peiffer
Acked-by: Serge Hallyn
Cc: Nadia Derbey
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The IPC_SET command performs the same permission setting for all IPCs. This
patch introduces a common ipc_update_perm() function to update these
permissions and makes use of it for all IPCs.Signed-off-by: Pierre Peiffer
Acked-by: Serge Hallyn
Cc: Nadia Derbey
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
All IPCs make use of an intermetiate *_setbuf structure to handle the IPC_SET
command. This is not really needed and, moreover, it complicates a little bit
the code.This patch gets rid of the use of it and uses directly the semid64_ds/
msgid64_ds/shmid64_ds structure.In addition of removing one struture declaration, it also simplifies and
improves a little bit the common 64-bits path.Signed-off-by: Pierre Peiffer
Acked-by: Serge Hallyn
Cc: Nadia Derbey
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently, sys_msgctl is not easy to read.
This patch tries to improve that by introducing the msgctl_down function to
handle all commands requiring the rwmutex to be taken in write mode (ie
IPC_SET and IPC_RMID for now). It is the equivalent function of semctl_down
for message queues.This greatly changes the readability of sys_msgctl and also harmonizes the way
these commands are handled among all IPCs.Signed-off-by: Pierre Peiffer
Acked-by: Serge Hallyn
Cc: Nadia Derbey
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Introduce the registration of a callback routine that recomputes msg_ctlmni
upon memory add / remove.A single notifier block is registered in the hotplug memory chain for all the
ipc namespaces.Since the ipc namespaces are not linked together, they have their own
notification chain: one notifier_block is defined per ipc namespace.Each time an ipc namespace is created (removed) it registers (unregisters) its
notifier block in (from) the ipcns chain. The callback routine registered in
the memory chain invokes the ipcns notifier chain with the IPCNS_LOWMEM event.
Each callback routine registered in the ipcns namespace, in turn, recomputes
msgmni for the owning namespace.Signed-off-by: Nadia Derbey
Cc: Yasunori Goto
Cc: Matt Helsley
Cc: Mingming Cao
Cc: Pierre Peiffer
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
