Inaugurate copy-on-write credentials management. This uses RCU to manage the
credentials pointer in the task_struct with respect to accesses by other tasks.
A process may only modify its own credentials, and so does not need locking to
access or modify its own credentials.
A mutex (cred_replace_mutex) is added to the task_struct to control the effect
of PTRACE_ATTACHED on credential calculations, particularly with respect to
execve().
With this patch, the contents of an active credentials struct may not be
changed directly; rather a new set of credentials must be prepared, modified
and committed using something like the following sequence of events:
struct cred *new = prepare_creds();
int ret = blah(new);
if (ret < 0) {
abort_creds(new);
return ret;
}
return commit_creds(new);
There are some exceptions to this rule: the keyrings pointed to by the active
credentials may be instantiated - keyrings violate the COW rule as managing
COW keyrings is tricky, given that it is possible for a task to directly alter
the keys in a keyring in use by another task.
To help enforce this, various pointers to sets of credentials, such as those in
the task_struct, are declared const. The purpose of this is compile-time
discouragement of altering credentials through those pointers. Once a set of
credentials has been made public through one of these pointers, it may not be
modified, except under special circumstances:
(1) Its reference count may incremented and decremented.
(2) The keyrings to which it points may be modified, but not replaced.
The only safe way to modify anything else is to create a replacement and commit
using the functions described in Documentation/credentials.txt (which will be
added by a later patch).
This patch and the preceding patches have been tested with the LTP SELinux
testsuite.
This patch makes several logical sets of alteration:
(1) execve().
This now prepares and commits credentials in various places in the
security code rather than altering the current creds directly.
(2) Temporary credential overrides.
do_coredump() and sys_faccessat() now prepare their own credentials and
temporarily override the ones currently on the acting thread, whilst
preventing interference from other threads by holding cred_replace_mutex
on the thread being dumped.
This will be replaced in a future patch by something that hands down the
credentials directly to the functions being called, rather than altering
the task's objective credentials.
(3) LSM interface.
A number of functions have been changed, added or removed:
(*) security_capset_check(), ->capset_check()
(*) security_capset_set(), ->capset_set()
Removed in favour of security_capset().
(*) security_capset(), ->capset()
New. This is passed a pointer to the new creds, a pointer to the old
creds and the proposed capability sets. It should fill in the new
creds or return an error. All pointers, barring the pointer to the
new creds, are now const.
(*) security_bprm_apply_creds(), ->bprm_apply_creds()
Changed; now returns a value, which will cause the process to be
killed if it's an error.
(*) security_task_alloc(), ->task_alloc_security()
Removed in favour of security_prepare_creds().
(*) security_cred_free(), ->cred_free()
New. Free security data attached to cred->security.
(*) security_prepare_creds(), ->cred_prepare()
New. Duplicate any security data attached to cred->security.
(*) security_commit_creds(), ->cred_commit()
New. Apply any security effects for the upcoming installation of new
security by commit_creds().
(*) security_task_post_setuid(), ->task_post_setuid()
Removed in favour of security_task_fix_setuid().
(*) security_task_fix_setuid(), ->task_fix_setuid()
Fix up the proposed new credentials for setuid(). This is used by
cap_set_fix_setuid() to implicitly adjust capabilities in line with
setuid() changes. Changes are made to the new credentials, rather
than the task itself as in security_task_post_setuid().
(*) security_task_reparent_to_init(), ->task_reparent_to_init()
Removed. Instead the task being reparented to init is referred
directly to init's credentials.
NOTE! This results in the loss of some state: SELinux's osid no
longer records the sid of the thread that forked it.
(*) security_key_alloc(), ->key_alloc()
(*) security_key_permission(), ->key_permission()
Changed. These now take cred pointers rather than task pointers to
refer to the security context.
(4) sys_capset().
This has been simplified and uses less locking. The LSM functions it
calls have been merged.
(5) reparent_to_kthreadd().
This gives the current thread the same credentials as init by simply using
commit_thread() to point that way.
(6) __sigqueue_alloc() and switch_uid()
__sigqueue_alloc() can't stop the target task from changing its creds
beneath it, so this function gets a reference to the currently applicable
user_struct which it then passes into the sigqueue struct it returns if
successful.
switch_uid() is now called from commit_creds(), and possibly should be
folded into that. commit_creds() should take care of protecting
__sigqueue_alloc().
(7) [sg]et[ug]id() and co and [sg]et_current_groups.
The set functions now all use prepare_creds(), commit_creds() and
abort_creds() to build and check a new set of credentials before applying
it.
security_task_set[ug]id() is called inside the prepared section. This
guarantees that nothing else will affect the creds until we've finished.
The calling of set_dumpable() has been moved into commit_creds().
Much of the functionality of set_user() has been moved into
commit_creds().
The get functions all simply access the data directly.
(8) security_task_prctl() and cap_task_prctl().
security_task_prctl() has been modified to return -ENOSYS if it doesn't
want to handle a function, or otherwise return the return value directly
rather than through an argument.
Additionally, cap_task_prctl() now prepares a new set of credentials, even
if it doesn't end up using it.
(9) Keyrings.
A number of changes have been made to the keyrings code:
(a) switch_uid_keyring(), copy_keys(), exit_keys() and suid_keys() have
all been dropped and built in to the credentials functions directly.
They may want separating out again later.
(b) key_alloc() and search_process_keyrings() now take a cred pointer
rather than a task pointer to specify the security context.
(c) copy_creds() gives a new thread within the same thread group a new
thread keyring if its parent had one, otherwise it discards the thread
keyring.
(d) The authorisation key now points directly to the credentials to extend
the search into rather pointing to the task that carries them.
(e) Installing thread, process or session keyrings causes a new set of
credentials to be created, even though it's not strictly necessary for
process or session keyrings (they're shared).
(10) Usermode helper.
The usermode helper code now carries a cred struct pointer in its
subprocess_info struct instead of a new session keyring pointer. This set
of credentials is derived from init_cred and installed on the new process
after it has been cloned.
call_usermodehelper_setup() allocates the new credentials and
call_usermodehelper_freeinfo() discards them if they haven't been used. A
special cred function (prepare_usermodeinfo_creds()) is provided
specifically for call_usermodehelper_setup() to call.
call_usermodehelper_setkeys() adjusts the credentials to sport the
supplied keyring as the new session keyring.
(11) SELinux.
SELinux has a number of changes, in addition to those to support the LSM
interface changes mentioned above:
(a) selinux_setprocattr() no longer does its check for whether the
current ptracer can access processes with the new SID inside the lock
that covers getting the ptracer's SID. Whilst this lock ensures that
the check is done with the ptracer pinned, the result is only valid
until the lock is released, so there's no point doing it inside the
lock.
(12) is_single_threaded().
This function has been extracted from selinux_setprocattr() and put into
a file of its own in the lib/ directory as join_session_keyring() now
wants to use it too.
The code in SELinux just checked to see whether a task shared mm_structs
with other tasks (CLONE_VM), but that isn't good enough. We really want
to know if they're part of the same thread group (CLONE_THREAD).
(13) nfsd.
The NFS server daemon now has to use the COW credentials to set the
credentials it is going to use. It really needs to pass the credentials
down to the functions it calls, but it can't do that until other patches
in this series have been applied.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: James Morris <jmorris@namei.org>
Due to confusion between the ftrace infrastructure and the gcc profiling
tracer "ftrace", this patch renames the config options from FTRACE to
FUNCTION_TRACER. The other two names that are offspring from FTRACE
DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same.
This patch was generated mostly by script, and partially by hand.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Base infrastructure to enable per-module debug messages.
I've introduced CONFIG_DYNAMIC_PRINTK_DEBUG, which when enabled centralizes
control of debugging statements on a per-module basis in one /proc file,
currently, <debugfs>/dynamic_printk/modules. When, CONFIG_DYNAMIC_PRINTK_DEBUG,
is not set, debugging statements can still be enabled as before, often by
defining 'DEBUG' for the proper compilation unit. Thus, this patch set has no
affect when CONFIG_DYNAMIC_PRINTK_DEBUG is not set.
The infrastructure currently ties into all pr_debug() and dev_dbg() calls. That
is, if CONFIG_DYNAMIC_PRINTK_DEBUG is set, all pr_debug() and dev_dbg() calls
can be dynamically enabled/disabled on a per-module basis.
Future plans include extending this functionality to subsystems, that define
their own debug levels and flags.
Usage:
Dynamic debugging is controlled by the debugfs file,
<debugfs>/dynamic_printk/modules. This file contains a list of the modules that
can be enabled. The format of the file is as follows:
<module_name> <enabled=0/1>
.
.
.
<module_name> : Name of the module in which the debug call resides
<enabled=0/1> : whether the messages are enabled or not
For example:
snd_hda_intel enabled=0
fixup enabled=1
driver enabled=0
Enable a module:
$echo "set enabled=1 <module_name>" > dynamic_printk/modules
Disable a module:
$echo "set enabled=0 <module_name>" > dynamic_printk/modules
Enable all modules:
$echo "set enabled=1 all" > dynamic_printk/modules
Disable all modules:
$echo "set enabled=0 all" > dynamic_printk/modules
Finally, passing "dynamic_printk" at the command line enables
debugging for all modules. This mode can be turned off via the above
disable command.
[gkh: minor cleanups and tweaks to make the build work quietly]
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch adds the ability to print sizes in either units of 10^3 (SI)
or 2^10 (Binary) units. It rounds up to three significant figures and
can be used for either memory or storage capacities.
Oh, and I'm fully aware that 64 bits is only 16EiB ... the Zetta and
Yotta units are added for future proofing against the day we have 128
bit computers ...
[fujita.tomonori@lab.ntt.co.jp: fix missed unsigned long long cast]
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This implements a platform-independent version of show_mem().
Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Bryan Wu <cooloney@kernel.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds the new function task_current_syscall() on machines where the
asm/syscall.h interface is supported (CONFIG_HAVE_ARCH_TRACEHOOK). It's
exported for modules to use in the future. This function safely samples
the state of a blocked thread to collect what system call it is blocked
in, and the six system call argument registers.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This updates <linux/bcd.h> to define the key routines as constant
functions, which the macros will then call. Newer code can now call
bcd2bin() instead of SCREAMING BCD2BIN() TO THE FOUR WINDS.
This lets each driver shrink their codespace by using N function calls to
a single (global) copy of those routines, instead of N inlined copies of
these functions per driver.
These routines aren't used in speed-critical code. Almost all callers are
in the RTC framework. Typical per-driver savings is near 300 bytes.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Adrian Bunk <bunk@kernel.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
make function tracing more robust: do not trace library functions.
We've already got a sizable list of exceptions:
ifdef CONFIG_FTRACE
# Do not profile string.o, since it may be used in early boot or vdso
CFLAGS_REMOVE_string.o = -pg
# Also do not profile any debug utilities
CFLAGS_REMOVE_spinlock_debug.o = -pg
CFLAGS_REMOVE_list_debug.o = -pg
CFLAGS_REMOVE_debugobjects.o = -pg
CFLAGS_REMOVE_find_next_bit.o = -pg
CFLAGS_REMOVE_cpumask.o = -pg
CFLAGS_REMOVE_bitmap.o = -pg
endif
... and the pattern has been that random library functionality showed
up in ftrace's critical path (outside of its recursion check), causing
hard to debug lockups.
So be a bit defensive about it and exclude all lib/*.o functions by
default. It's not that they are overly interesting for tracing purposes
anyway. Specific ones can still be traced, in an opt-in manner.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
MAXSMP brings in lots of use of various bitops in smp_processor_id()
and friends - causing ftrace to lock up during bootup:
calling anon_inode_init+0x0/0x130
initcall anon_inode_init+0x0/0x130 returned 0 after 0 msecs
calling acpi_event_init+0x0/0x57
[ hard hang ]
So exclude the bitops facilities from tracing.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (102 commits)
[SCSI] scsi_dh: fix kconfig related build errors
[SCSI] sym53c8xx: Fix bogus sym_que_entry re-implementation of container_of
[SCSI] scsi_cmnd.h: remove double inclusion of linux/blkdev.h
[SCSI] make struct scsi_{host,target}_type static
[SCSI] fix locking in host use of blk_plug_device()
[SCSI] zfcp: Cleanup external header file
[SCSI] zfcp: Cleanup code in zfcp_erp.c
[SCSI] zfcp: zfcp_fsf cleanup.
[SCSI] zfcp: consolidate sysfs things into one file.
[SCSI] zfcp: Cleanup of code in zfcp_aux.c
[SCSI] zfcp: Cleanup of code in zfcp_scsi.c
[SCSI] zfcp: Move status accessors from zfcp to SCSI include file.
[SCSI] zfcp: Small QDIO cleanups
[SCSI] zfcp: Adapter reopen for large number of unsolicited status
[SCSI] zfcp: Fix error checking for ELS ADISC requests
[SCSI] zfcp: wait until adapter is finished with ERP during auto-port
[SCSI] ibmvfc: IBM Power Virtual Fibre Channel Adapter Client Driver
[SCSI] sg: Add target reset support
[SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC
[SCSI] sd: Move scsi_disk() accessor function to sd.h
...
The SCSI Block Protocol uses this 16-bit CRC to verify the integrity
of each data sector. crc_t10dif() is used by sd_dif.c when performing
I/O to or from disks formatted with protection information.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This patch removes the Makefile turd and uses the nice CFLAGS_REMOVE macro
in the lib directory.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The debug functions in spin_lock debugging pollute the output of the
function tracer. This patch adds the debug files in the lib director
to those that should not be compiled with mcount tracing.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Most archs define the string and memory compare functions in assembly.
Some do not. But these functions may be used in some archs at early
boot up.
Since most archs define this code in assembly and they are not usually
traced, there's no need to trace them when they are not defined in
assembly.
This patch removes the -pg from the CFLAGS for lib/string.o.
This prevents the string functions use in either vdso or early bootup
from crashing the system.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
We can see an ever repeating problem pattern with objects of any kind in the
kernel:
1) freeing of active objects
2) reinitialization of active objects
Both problems can be hard to debug because the crash happens at a point where
we have no chance to decode the root cause anymore. One problem spot are
kernel timers, where the detection of the problem often happens in interrupt
context and usually causes the machine to panic.
While working on a timer related bug report I had to hack specialized code
into the timer subsystem to get a reasonable hint for the root cause. This
debug hack was fine for temporary use, but far from a mergeable solution due
to the intrusiveness into the timer code.
The code further lacked the ability to detect and report the root cause
instantly and keep the system operational.
Keeping the system operational is important to get hold of the debug
information without special debugging aids like serial consoles and special
knowledge of the bug reporter.
The problems described above are not restricted to timers, but timers tend to
expose it usually in a full system crash. Other objects are less explosive,
but the symptoms caused by such mistakes can be even harder to debug.
Instead of creating specialized debugging code for the timer subsystem a
generic infrastructure is created which allows developers to verify their code
and provides an easy to enable debug facility for users in case of trouble.
The debugobjects core code keeps track of operations on static and dynamic
objects by inserting them into a hashed list and sanity checking them on
object operations and provides additional checks whenever kernel memory is
freed.
The tracked object operations are:
- initializing an object
- adding an object to a subsystem list
- deleting an object from a subsystem list
Each operation is sanity checked before the operation is executed and the
subsystem specific code can provide a fixup function which allows to prevent
the damage of the operation. When the sanity check triggers a warning message
and a stack trace is printed.
The list of operations can be extended if the need arises. For now it's
limited to the requirements of the first user (timers).
The core code enqueues the objects into hash buckets. The hash index is
generated from the address of the object to simplify the lookup for the check
on kfree/vfree. Each bucket has it's own spinlock to avoid contention on a
global lock.
The debug code can be compiled in without being active. The runtime overhead
is minimal and could be optimized by asm alternatives. A kernel command line
option enables the debugging code.
Thanks to Ingo Molnar for review, suggestions and cleanup patches.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Greg KH <greg@kroah.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Due to the rcupreempt.h WARN_ON trigged, I got 2G syslog file. For some
serious complaining of kernel, we need repeat the warnings, so here I isolate
the ratelimit part of printk.c to a standalone file.
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Generic versions of __find_first_bit and __find_first_zero_bit
are introduced as simplified versions of __find_next_bit and
__find_next_zero_bit. Their compilation and use are guarded by
a new config variable GENERIC_FIND_FIRST_BIT.
The generic versions of find_first_bit and find_first_zero_bit
are implemented in terms of the newly introduced __find_first_bit
and __find_first_zero_bit.
This patch does not remove the i386-specific implementation,
but it does switch i386 to use the generic functions by setting
GENERIC_FIND_FIRST_BIT=y for X86_32.
Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (202 commits)
[POWERPC] Fix compile breakage for 64-bit UP configs
[POWERPC] Define copy_siginfo_from_user32
[POWERPC] Add compat handler for PTRACE_GETSIGINFO
[POWERPC] i2c: Fix build breakage introduced by OF helpers
[POWERPC] Optimize fls64() on 64-bit processors
[POWERPC] irqtrace support for 64-bit powerpc
[POWERPC] Stacktrace support for lockdep
[POWERPC] Move stackframe definitions to common header
[POWERPC] Fix device-tree locking vs. interrupts
[POWERPC] Make pci_bus_to_host()'s struct pci_bus * argument const
[POWERPC] Remove unused __max_memory variable
[POWERPC] Simplify xics direct/lpar irq_host setup
[POWERPC] Use pseries_setup_i8259_cascade() in pseries_mpic_init_IRQ()
[POWERPC] Turn xics_setup_8259_cascade() into a generic pseries_setup_i8259_cascade()
[POWERPC] Move xics_setup_8259_cascade() into platforms/pseries/setup.c
[POWERPC] Use asm-generic/bitops/find.h in bitops.h
[POWERPC] 83xx: mpc8315 - fix USB UTMI Host setup
[POWERPC] 85xx: Fix the size of qe muram for MPC8568E
[POWERPC] 86xx: mpc86xx_hpcn - Temporarily accept old dts node identifier.
[POWERPC] 86xx: mark functions static, other minor cleanups
...
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.26: (1090 commits)
[NET]: Fix and allocate less memory for ->priv'less netdevices
[IPV6]: Fix dangling references on error in fib6_add().
[NETLABEL]: Fix NULL deref in netlbl_unlabel_staticlist_gen() if ifindex not found
[PKT_SCHED]: Fix datalen check in tcf_simp_init().
[INET]: Uninline the __inet_inherit_port call.
[INET]: Drop the inet_inherit_port() call.
SCTP: Initialize partial_bytes_acked to 0, when all of the data is acked.
[netdrvr] forcedeth: internal simplifications; changelog removal
phylib: factor out get_phy_id from within get_phy_device
PHY: add BCM5464 support to broadcom PHY driver
cxgb3: Fix __must_check warning with dev_dbg.
tc35815: Statistics cleanup
natsemi: fix MMIO for PPC 44x platforms
[TIPC]: Cleanup of TIPC reference table code
[TIPC]: Optimized initialization of TIPC reference table
[TIPC]: Remove inlining of reference table locking routines
e1000: convert uint16_t style integers to u16
ixgb: convert uint16_t style integers to u16
sb1000.c: make const arrays static
sb1000.c: stop inlining largish static functions
...
Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility. Thanks to Peter Zijlstra for fixing the lockdep
warning. Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
The knock-out. The pcounter abstraction is not used any longer in the
kernel.
Not sure whether this should go via netdev tree, but as far as I
remember it was added via this one, and besides Eric thinks that
Andrew shouldn't mind this.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
lib/scatterlist.c is needed by drivers/media/video/videobuf-dma-sg.c, and
we would like to be able to use the latter without PCI too, for example, on
PXA270 ARM CPU. It is then possible to create a configuration with
CONFIG_BLOCK=n, where only module code will need scatterlist.c. Therefore
it must be in obj-y.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds IOMMU helper functions for the free area management. These
functions take care of LLD's segment boundary limit for IOMMUs. They would be
useful for IOMMUs that use bitmap for the free area management.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This just generalises what was introduced by Eric Dumazet for the struct proto
inuse field in 286ab3d460:
[NET]: Define infrastructure to keep 'inuse' changes in an efficent SMP/NUMA way.
Please look at the comment in there to see the rationale.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Manually doing chained sg lists is not trivial, so add some helpers
to make sure that drivers get it right.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
mac80211 has a reference to __bitmap_empty() via bitmap_empty(). In
lib/bitmap.c this is flagged with an EXPORT_SYMBOL(), but this is
ultimately ineffective due to bitmap.o being linked in lib-y, resulting in:
ERROR: "__bitmap_empty" [net/mac80211/mac80211.ko] undefined!
Moving bitmap.o to obj-y fixes this up.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: "John W. Linville" <linville@tuxdriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cause writes to cpuset "cpus" file to update cpus_allowed for member tasks:
- collect batches of tasks under tasklist_lock and then call
set_cpus_allowed() on them outside the lock (since this can sleep).
- add a simple generic priority heap type to allow efficient collection
of batches of tasks to be processed without duplicating or missing any
tasks in subsequent batches.
- make "cpus" file update a no-op if the mask hasn't changed
- fix race between update_cpumask() and sched_setaffinity() by making
sched_setaffinity() post-check that it's not running on any cpus outside
cpuset_cpus_allowed().
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Cedric Le Goater <clg@fr.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Given a set of objects, floating proportions aims to efficiently give the
proportional 'activity' of a single item as compared to the whole set. Where
'activity' is a measure of a temporal property of the items.
It is efficient in that it need not inspect any other items of the set
in order to provide the answer. It is not even needed to know how many
other items there are.
It has one parameter, and that is the period of 'time' over which the
'activity' is measured.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move uevent specific logic from the core into kobject_uevent.c, which
does no longer require to link the unused string array if hotplug
is not compiled in.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Introduce CONFIG_CHECK_SIGNATURE to control inclusion of check_signature()
and avoid problems on platforms that don't have readb().
Let the few legacy (ISA || PCI || X86) drivers that need check_signature()
select CONFIG_CHECK_SIGNATURE.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kasprintf pulls in kmalloc which proved to be fatal for at least
bootimage target on alpha.
Move it to a separate file so only users of kasprintf are exposed
to the dependency on kmalloc.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Meelis Roos <mroos@linux.ee>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Jay Estabrook <jay.estabrook@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
argv_split() is a helper function which takes a string, splits it at
whitespace, and returns a NULL-terminated argv vector. This is
deliberately simple - it does no quote processing of any kind.
[ Seems to me that this is something which is already being done in
the kernel, but I couldn't find any other implementations, either to
steal or replace. Keep an eye out. ]
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Add CRC7 routines, used for example in MMC over SPI communication.
Kerneldoc updates
[akpm@linux-foundation.org: fix funny mix of const and non-const]
Signed-off-by: Jan Nikitenko <jan.nikitenko@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This should avoid build problems on architectures without a "readb()",
that got bitten by check_signature() being uninlined.
Noted by Heiko Carstens.
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a rather bizarre thing to have inlined in io.h. Stick it in lib/
instead.
While we're there, despaghetti it a bit, and fix its off-by-one behaviour when
passed a zero length.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a hybrid version of the patch to add the LZO1X compression
algorithm to the kernel. Nitin and myself have merged the best parts of
the various patches to form this version which we're both happy with (and
are jointly signing off).
The performance of this version is equivalent to the original minilzo code
it was based on. Bytecode comparisons have also been made on ARM, i386 and
x86_64 with favourable results.
There are several users of LZO lined up including jffs2, crypto and reiser4
since its much faster than zlib.
Signed-off-by: Nitin Gupta <nitingupta910@gmail.com>
Signed-off-by: Richard Purdie <rpurdie@openedhand.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Based on ace_dump_mem() from Grant Likely for the Xilinx SystemACE
CompactFlash interface.
Add print_hex_dump() & hex_dumper() to lib/hexdump.c and linux/kernel.h.
This patch adds the functions print_hex_dump() & hex_dumper().
print_hex_dump() can be used to perform a hex + ASCII dump of data to
syslog, in an easily viewable format, thus providing a common text hex dump
format.
hex_dumper() provides a dump-to-memory function. It converts one "line" of
output (16 bytes of input) at a time.
Example usages:
print_hex_dump(KERN_DEBUG, DUMP_PREFIX_ADDRESS, frame->data, frame->len);
hex_dumper(frame->data, frame->len, linebuf, sizeof(linebuf));
Example output using %DUMP_PREFIX_OFFSET:
0009ab42: 40414243 44454647 48494a4b 4c4d4e4f-@ABCDEFG HIJKLMNO
Example output using %DUMP_PREFIX_ADDRESS:
ffffffff88089af0: 70717273 74757677 78797a7b 7c7d7e7f-pqrstuvw xyz{|}~.
[akpm@linux-foundation.org: cleanups, add export]
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'juju' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: (138 commits)
firewire: Convert OHCI driver to use standard goto unwinding for error handling.
firewire: Always use parens with sizeof.
firewire: Drop single buffer request support.
firewire: Add a comment to describe why we split the sg list.
firewire: Return SCSI_MLQUEUE_HOST_BUSY for out of memory cases in queuecommand.
firewire: Handle the last few DMA mapping error cases.
firewire: Allocate scsi_host up front and allocate the sbp2_device as hostdata.
firewire: Provide module aliase for backwards compatibility.
firewire: Add to fw-core-y instead of assigning fw-core-objs in Makefile.
firewire: Break out shared IEEE1394 constant to separate header file.
firewire: Use linux/*.h instead of asm/*.h header files.
firewire: Uppercase most macro names.
firewire: Coding style cleanup: no spaces after function names.
firewire: Convert card_rwsem to a regular mutex.
firewire: Clean up comment style.
firewire: Use lib/ implementation of CRC ITU-T.
CRC ITU-T V.41
firewire: Rename fw-device-cdev.c to fw-cdev.c and move header to include/linux.
firewire: Future proof the iso ioctls by adding a handle for the iso context.
firewire: Add read/write and size annotations to IOC numbers.
...
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This will add the CRC calculation according
to the CRC ITU-T V.41 to the kernel lib/ folder.
This code has been derived from the rt2x00 driver,
currently found only in the wireless-dev tree, but
this library is generic and could be used by more
drivers who currently use their own implementation.
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Also useful for the new firewire stack.
Signed-off-by: Kristian Hoegsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Here is the current version of the 64 bit divide common code.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Split the implementation-agnostic stuff in separate files.
* Make sure that targets using non-default request_irq() pull
kernel/irq/devres.o
* Introduce new symbols (HAS_IOPORT and HAS_IOMEM) defaulting to positive;
allow architectures to turn them off (we needed these symbols anyway for
dependencies of quite a few drivers).
* protect the ioport-related parts of lib/devres.o with CONFIG_HAS_IOPORT.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Part of long forgotten patch
http://groups.google.com/group/fa.linux.kernel/msg/e98e941ce1cf29f6?dmode=source
Since then, m32r grabbed two copies.
Leave s390 copy because of important absence of CONFIG_VT, but remove
references to non-existent timerlist_lock. ia64 also loses timerlist_lock.
Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
devres change moved iomap.o from obj-$(CONFIG_GENERIC_IOMAP) to lib-y
making it not linked if no in-kernel driver uses it. Fix it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement device resource management, in short, devres. A device
driver can allocate arbirary size of devres data which is associated
with a release function. On driver detach, release function is
invoked on the devres data, then, devres data is freed.
devreses are typed by associated release functions. Some devreses are
better represented by single instance of the type while others need
multiple instances sharing the same release function. Both usages are
supported.
devreses can be grouped using devres group such that a device driver
can easily release acquired resources halfway through initialization
or selectively release resources (e.g. resources for port 1 out of 4
ports).
This patch adds devres core including documentation and the following
managed interfaces.
* alloc/free : devm_kzalloc(), devm_kzfree()
* IO region : devm_request_region(), devm_release_region()
* IRQ : devm_request_irq(), devm_free_irq()
* DMA : dmam_alloc_coherent(), dmam_free_coherent(),
dmam_declare_coherent_memory(), dmam_pool_create(),
dmam_pool_destroy()
* PCI : pcim_enable_device(), pcim_pin_device(), pci_is_managed()
* iomap : devm_ioport_map(), devm_ioport_unmap(), devm_ioremap(),
devm_ioremap_nocache(), devm_iounmap(), pcim_iomap_table(),
pcim_iomap(), pcim_iounmap()
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Remove useless includes of linux/io.h, don't even try to build iomap_copy
on uml (it doesn't have readb() et.al., so...)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When some objects are allocated by one CPU but freed by another CPU we can
consume lot of cycles doing divides in obj_to_index().
(Typical load on a dual processor machine where network interrupts are
handled by one particular CPU (allocating skbufs), and the other CPU is
running the application (consuming and freeing skbufs))
Here on one production server (dual-core AMD Opteron 285), I noticed this
divide took 1.20 % of CPU_CLK_UNHALTED events in kernel. But Opteron are
quite modern cpus and the divide is much more expensive on oldest
architectures :
On a 200 MHz sparcv9 machine, the division takes 64 cycles instead of 1
cycle for a multiply.
Doing some math, we can use a reciprocal multiplication instead of a divide.
If we want to compute V = (A / B) (A and B being u32 quantities)
we can instead use :
V = ((u64)A * RECIPROCAL(B)) >> 32 ;
where RECIPROCAL(B) is precalculated to ((1LL << 32) + (B - 1)) / B
Note :
I wrote pure C code for clarity. gcc output for i386 is not optimal but
acceptable :
mull 0x14(%ebx)
mov %edx,%eax // part of the >> 32
xor %edx,%edx // useless
mov %eax,(%esp) // could be avoided
mov %edx,0x4(%esp) // useless
mov (%esp),%ebx
[akpm@osdl.org: small cleanups]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides base functions implement to fault-injection
capabilities.
- The function should_fail() is taken from failmalloc-1.0
(http://www.nongnu.org/failmalloc/)
[akpm@osdl.org: cleanups, comments, add __init]
Cc: <okuji@enbug.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Don Mullis <dwm@meer.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch provides two bit reverse functions and bit reverse table.
- reverse the order of bits in a u32 value
u8 bitrev8(u8 x);
- reverse the order of bits in a u32 value
u32 bitrev32(u32 x);
- byte reverse table
const u8 byte_rev_table[256];
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
