Pull btrfs updates from Chris Mason:
"This is a pretty big pull, and most of these changes have been
floating in btrfs-next for a long time. Filipe's properties work is a
cool building block for inheriting attributes like compression down on
a per inode basis.
Jeff Mahoney kicked in code to export filesystem info into sysfs.
Otherwise, lots of performance improvements, cleanups and bug fixes.
Looks like there are still a few other small pending incrementals, but
I wanted to get the bulk of this in first"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (149 commits)
Btrfs: fix spin_unlock in check_ref_cleanup
Btrfs: setup inode location during btrfs_init_inode_locked
Btrfs: don't use ram_bytes for uncompressed inline items
Btrfs: fix btrfs_search_slot_for_read backwards iteration
Btrfs: do not export ulist functions
Btrfs: rework ulist with list+rb_tree
Btrfs: fix memory leaks on walking backrefs failure
Btrfs: fix send file hole detection leading to data corruption
Btrfs: add a reschedule point in btrfs_find_all_roots()
Btrfs: make send's file extent item search more efficient
Btrfs: fix to catch all errors when resolving indirect ref
Btrfs: fix protection between walking backrefs and root deletion
btrfs: fix warning while merging two adjacent extents
Btrfs: fix infinite path build loops in incremental send
btrfs: undo sysfs when open_ctree() fails
Btrfs: fix snprintf usage by send's gen_unique_name
btrfs: fix defrag 32-bit integer overflow
btrfs: sysfs: list the NO_HOLES feature
btrfs: sysfs: don't show reserved incompat feature
btrfs: call permission checks earlier in ioctls and return EPERM
...
possible, because the eraseblock may be in an "unstable" state and write
operation sometimes causes NOR chip lock-ups.
* Both UBI and UBIFS changes are now maintainer in one single tree, because the
amount of changes dropped significantly.
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Merge tag 'upstream-3.14-rc1' of git://git.infradead.org/linux-ubifs
Pull ubifs updates from Artem Bityutskiy:
- Improve the NOR erasure quirk - now it tries to do as little writes
as possible, because the eraseblock may be in an "unstable" state and
write operation sometimes causes NOR chip lock-ups.
- Both UBI and UBIFS changes are now maintainer in one single tree,
because the amount of changes dropped significantly.
* tag 'upstream-3.14-rc1' of git://git.infradead.org/linux-ubifs:
UBI: avoid program operation on NOR flash after erasure interrupted
MAINTAINERS: keep UBI and UBIFS stuff in the same tree
UBI: fix error return code
Pull some further ceph acl cleanups from Sage Weil:
"I do have a couple patches on top of what's in your tree, though, that
clean up a couple duplicated lines in your fix and apply Christoph's
cleanup"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: simplify ceph_{get,init}_acl
ceph: remove duplicate declaration of ceph_setattr
- ->get_acl only gets called after we checked for a cached ACL, so no
need to call get_cached_acl again.
- no need to check IS_POSIXACL in ->get_acl, without that it should
never get set as all the callers that set it already have the check.
- you should be able to use the full posix_acl_create in CEPH
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Sage Weil <sage@inktank.com>
Merge misc fixes from Andrew Morton:
"A few hotfixes and various leftovers which were awaiting other merges.
Mainly movement of zram into mm/"
* emailed patches fron Andrew Morton <akpm@linux-foundation.org>: (25 commits)
memcg: fix mutex not unlocked on memcg_create_kmem_cache fail path
Documentation/filesystems/vfs.txt: update file_operations documentation
mm, oom: base root bonus on current usage
mm: don't lose the SOFT_DIRTY flag on mprotect
mm/slub.c: fix page->_count corruption (again)
mm/mempolicy.c: fix mempolicy printing in numa_maps
zram: remove zram->lock in read path and change it with mutex
zram: remove workqueue for freeing removed pending slot
zram: introduce zram->tb_lock
zram: use atomic operation for stat
zram: remove unnecessary free
zram: delay pending free request in read path
zram: fix race between reset and flushing pending work
zsmalloc: add maintainers
zram: add zram maintainers
zsmalloc: add copyright
zram: add copyright
zram: remove old private project comment
zram: promote zram from staging
zsmalloc: move it under mm
...
The x32 case for the recvmsg() timout handling is broken:
asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg,
unsigned int vlen, unsigned int flags,
struct compat_timespec __user *timeout)
{
int datagrams;
struct timespec ktspec;
if (flags & MSG_CMSG_COMPAT)
return -EINVAL;
if (COMPAT_USE_64BIT_TIME)
return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen,
flags | MSG_CMSG_COMPAT,
(struct timespec *) timeout);
...
The timeout pointer parameter is provided by userland (hence the __user
annotation) but for x32 syscalls it's simply cast to a kernel pointer
and is passed to __sys_recvmmsg which will eventually directly
dereference it for both reading and writing. Other callers to
__sys_recvmmsg properly copy from userland to the kernel first.
The bug was introduced by commit ee4fa23c4b ("compat: Use
COMPAT_USE_64BIT_TIME in net/compat.c") and should affect all kernels
since 3.4 (and perhaps vendor kernels if they backported x32 support
along with this code).
Note that CONFIG_X86_X32_ABI gets enabled at build time and only if
CONFIG_X86_X32 is enabled and ld can build x32 executables.
Other uses of COMPAT_USE_64BIT_TIME seem fine.
This addresses CVE-2014-0038.
Signed-off-by: PaX Team <pageexec@freemail.hu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org> # v3.4+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 asmlinkage (LTO) changes from Peter Anvin:
"This patchset adds more infrastructure for link time optimization
(LTO).
This patchset was pulled into my tree late because of a
miscommunication (part of the patchset was picked up by other
maintainers). However, the patchset is strictly build-related and
seems to be okay in testing"
* 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, asmlinkage, xen: Fix type of NMI
x86, asmlinkage, xen, kvm: Make {xen,kvm}_lock_spinning global and visible
x86: Use inline assembler instead of global register variable to get sp
x86, asmlinkage, paravirt: Make paravirt thunks global
x86, asmlinkage, paravirt: Don't rely on local assembler labels
x86, asmlinkage, lguest: Fix C functions used by inline assembler
Pull x86 build bits from Peter Anvin:
"Various build-related minor bits.
Most of this is work by David Woodhouse to be able to compile the
early boot code with clang/llvm; we have also managed to push an
actual -m16 option into gcc 4.9 so this makes us use that option if
available instead of hacking it.
The balance is a patch from Michael Davidson to the relocs program to
help manual debugging.
None of these should change the actual compiled binary with currently
released compilers"
* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, build: Build 16-bit code with -m16 where possible
x86, boot: Fix word-size assumptions in has_eflag() inline asm
x86, boot: Use __attribute__((used)) to ensure videocard structs are emitted
x86: Remove duplication of 16-bit CFLAGS
x86, relocs: Add manual debug mode
These are changes that arrived a little late but were considered
self-contained enough to still go in for v3.14.
They are all device tree updtes this time around, and mainly for
Broadcom SoCs.
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Merge tag 'late-dt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC late changes from Kevin Hilman:
"These are changes that arrived a little late but were considered
self-contained enough to still go in for v3.14.
They are all device tree updtes this time around, and mainly for
Broadcom SoCs"
* tag 'late-dt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
ARM: moxart: move fixed rate clock child node to board level dts
clk: bcm281xx: define kona clock binding
ARM: dts: add usb udc support to bcm281xx
ARM: dts: Specify clocks for timer on bcm11351
Documentation: dt: kona-timer: Add clocks property
ARM: dts: Specify clocks for SDHCIs on bcm11351
Documentation: dt: kona-sdhci: Add clocks property
ARM: dts: Specify clocks for UARTs on bcm11351
ARM: dts: bcm281xx: Add i2c busses
ARM: dts: Declare clocks as fixed on bcm11351
ARM: dts: bcm28155-ap: Enable all the i2c busses
Pull MIPS updates from Ralf Baechle:
"The most notable new addition inside this pull request is the support
for MIPS's latest and greatest core called "inter/proAptiv". The
patch series describes this core as follows.
"The interAptiv is a power-efficient multi-core microprocessor
for use in system-on-chip (SoC) applications. The interAptiv combines
a multi-threading pipeline with a coherence manager to deliver improved
computational throughput and power efficiency. The interAptiv can
contain one to four MIPS32R3 interAptiv cores, system level
coherence manager with L2 cache, optional coherent I/O port,
and optional floating point unit."
The platform specific patches touch all 3 Broadcom families. It adds
support for the new Broadcom/Netlogix XLP9xx Soc, building a common
BCM63XX SMP kernel for all BCM63XX SoCs regardless of core type/count
and full gpio button/led descriptions for BCM47xx.
The rest of the series are cleanups and bug fixes that are MIPS
generic and consist largely of changes that Imgtec/MIPS had published
in their linux-mti-3.10.git stable tree. Random other cleanups and
patches preparing code to be merged in 3.15"
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (139 commits)
mips: select ARCH_MIGHT_HAVE_PC_SERIO
mips: delete non-required instances of include <linux/init.h>
MIPS: KVM: remove shadow_tlb code
MIPS: KVM: use common EHINV aware UNIQUE_ENTRYHI
mips/ide: flush dcache also if icache does not snoop dcache
MIPS: BCM47XX: fix position of cpu_wait disabling
MIPS: BCM63XX: select correct MIPS_L1_CACHE_SHIFT value
MIPS: update MIPS_L1_CACHE_SHIFT based on MIPS_L1_CACHE_SHIFT_<N>
MIPS: introduce MIPS_L1_CACHE_SHIFT_<N>
MIPS: ZBOOT: gather string functions into string.c
arch/mips/pci: don't check resource with devm_ioremap_resource
arch/mips/lantiq/xway: don't check resource with devm_ioremap_resource
bcma: gpio: don't cast u32 to unsigned long
ssb: gpio: add own IRQ domain
MIPS: BCM47XX: fix sparse warnings in board.c
MIPS: BCM47XX: add board detection for Linksys WRT54GS V1
MIPS: BCM47XX: fix detection for some boards
MIPS: BCM47XX: Enable buttons support on SSB
MIPS: BCM47XX: Convert WNDR4500 to new syntax
MIPS: BCM47XX: Use "timer" trigger for status LEDs
...
The interesting change here is a rework of the OpenRISC signal handling
to make it more like other architectures in the hopes that this
makes it easier for others to comment on and understand. This
rework fixes some real bugs, like the fact that syscall restart
did not work reliably.
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Merge tag 'for-3.14' of git://openrisc.net/~jonas/linux
Pull OpenRISC updates from Jonas Bonn:
"The interesting change here is a rework of the OpenRISC signal
handling to make it more like other architectures in the hopes that
this makes it easier for others to comment on and understand. This
rework fixes some real bugs, like the fact that syscall restart did
not work reliably"
* tag 'for-3.14' of git://openrisc.net/~jonas/linux:
openrisc: Use get_signal() signal_setup_done()
openrisc: Rework signal handling
Pull more powerpc bits from Ben Herrenschmidt:
"Here are a few more powerpc bits for this merge window. The bulk is
made of two pull requests from Scott and Anatolij that I had missed
previously (they arrived while I was away). Since both their branches
are in -next independently, and the content has been around for a
little while, they can still go in.
The rest is mostly bug and regression fixes, a small series of
cleanups to our pseries cpuidle code (including moving it to the right
place), and one new cpuidle bakend for the powernv platform. I also
wired up the new sched_attr syscalls"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (37 commits)
powerpc: Wire up sched_setattr and sched_getattr syscalls
powerpc/hugetlb: Replace __get_cpu_var with get_cpu_var
powerpc: Make sure "cache" directory is removed when offlining cpu
powerpc/mm: Fix mmap errno when MAP_FIXED is set and mapping exceeds the allowed address space
powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform.
powerpc/pseries/cpuidle: smt-snooze-delay cleanup.
powerpc/pseries/cpuidle: Remove MAX_IDLE_STATE macro.
powerpc/pseries/cpuidle: Make cpuidle-pseries backend driver a non-module.
powerpc/pseries/cpuidle: Use cpuidle_register() for initialisation.
powerpc/pseries/cpuidle: Move processor_idle.c to drivers/cpuidle.
powerpc: Fix 32-bit frames for signals delivered when transactional
powerpc/iommu: Fix initialisation of DART iommu table
powerpc/numa: Fix decimal permissions
powerpc/mm: Fix compile error of pgtable-ppc64.h
powerpc: Fix hw breakpoints on !HAVE_HW_BREAKPOINT configurations
clk: corenet: Adds the clock binding
powerpc/booke64: Guard e6500 tlb handler with CONFIG_PPC_FSL_BOOK3E
powerpc/512x: dts: add MPC5125 clock specs
powerpc/512x: clk: support MPC5121/5123/5125 SoC variants
powerpc/512x: clk: enforce even SDHC divider values
...
Pull __TIME__/__DATE__ removal from Michal Marek:
"This series by Josh finishes the removal of __DATE__ and __TIME__ from
the kernel. The last patch adds -Werror=date-time to KBUILD_CFLAGS to
stop these from reappearing.
Part of the series went through Greg's trees during this merge window,
which is why this pull request is not based on v3.13-rc1"
* 'drop-time' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
Makefile: Build with -Werror=date-time if the compiler supports it
x86: math-emu: Drop already-disabled print of build date
net: wireless: brcm80211: Drop debug version with build date/time
mtd: denali: Drop print of build date/time
Pull kbuild changes from Michal Marek:
- fix make -s detection with make-4.0
- fix for scripts/setlocalversion when the kernel repository is a
submodule
- do not hardcode ';' in macros that expand to assembler code, as some
architectures' assemblers use a different character for newline
- Fix passing --gdwarf-2 to the assembler
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
frv: Remove redundant debugging info flag
mn10300: Remove redundant debugging info flag
kbuild: Fix debugging info generation for .S files
arch: use ASM_NL instead of ';' for assembler new line character in the macro
kbuild: Fix silent builds with make-4
Fix detectition of kernel git repository in setlocalversion script [take #2]
Commit 842e287369 ("memcg: get rid of kmem_cache_dup()") introduced a
mutex for memcg_create_kmem_cache() to protect the tmp_name buffer that
holds the memcg name. It failed to unlock the mutex if this buffer
could not be allocated.
This patch fixes the issue by appropriately unlocking the mutex if the
allocation fails.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Glauber Costa <glommer@parallels.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
->readv, ->writev and ->sendfile have been removed while ->show_fdinfo
has been added. The documentation should reflect this.
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A 3% of system memory bonus is sometimes too excessive in comparison to
other processes.
With commit a63d83f427 ("oom: badness heuristic rewrite"), the OOM
killer tries to avoid killing privileged tasks by subtracting 3% of
overall memory (system or cgroup) from their per-task consumption. But
as a result, all root tasks that consume less than 3% of overall memory
are considered equal, and so it only takes 33+ privileged tasks pushing
the system out of memory for the OOM killer to do something stupid and
kill dhclient or other root-owned processes. For example, on a 32G
machine it can't tell the difference between the 1M agetty and the 10G
fork bomb member.
The changelog describes this 3% boost as the equivalent to the global
overcommit limit being 3% higher for privileged tasks, but this is not
the same as discounting 3% of overall memory from _every privileged task
individually_ during OOM selection.
Replace the 3% of system memory bonus with a 3% of current memory usage
bonus.
By giving root tasks a bonus that is proportional to their actual size,
they remain comparable even when relatively small. In the example
above, the OOM killer will discount the 1M agetty's 256 badness points
down to 179, and the 10G fork bomb's 262144 points down to 183500 points
and make the right choice, instead of discounting both to 0 and killing
agetty because it's first in the task list.
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The SOFT_DIRTY bit shows that the content of memory was changed after a
defined point in the past. mprotect() doesn't change the content of
memory, so it must not change the SOFT_DIRTY bit.
This bug causes a malfunction: on the first iteration all pages are
dumped. On other iterations only pages with the SOFT_DIRTY bit are
dumped. So if the SOFT_DIRTY bit is cleared from a page by mistake, the
page is not dumped and its content will be restored incorrectly.
This patch does nothing with _PAGE_SWP_SOFT_DIRTY, becase pte_modify()
is called only for present pages.
Fixes commit 0f8975ec4d ("mm: soft-dirty bits for user memory changes
tracking").
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit abca7c4965 ("mm: fix slab->page _count corruption when using
slub") notes that we can not _set_ a page->counters directly, except
when using a real double-cmpxchg. Doing so can lose updates to
->_count.
That is an absolute rule:
You may not *set* page->counters except via a cmpxchg.
Commit abca7c4965 fixed this for the folks who have the slub
cmpxchg_double code turned off at compile time, but it left the bad case
alone. It can still be reached, and the same bug triggered in two
cases:
1. Turning on slub debugging at runtime, which is available on
the distro kernels that I looked at.
2. On 64-bit CPUs with no CMPXCHG16B (some early AMD x86-64
cpus, evidently)
There are at least 3 ways we could fix this:
1. Take all of the exising calls to cmpxchg_double_slab() and
__cmpxchg_double_slab() and convert them to take an old, new
and target 'struct page'.
2. Do (1), but with the newly-introduced 'slub_data'.
3. Do some magic inside the two cmpxchg...slab() functions to
pull the counters out of new_counters and only set those
fields in page->{inuse,frozen,objects}.
I've done (2) as well, but it's a bunch more code. This patch is an
attempt at (3). This was the most straightforward and foolproof way
that I could think to do this.
This would also technically allow us to get rid of the ugly
#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \
defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE)
in 'struct page', but leaving it alone has the added benefit that
'counters' stays 'unsigned' instead of 'unsigned long', so all the
copies that the slub code does stay a bit smaller.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As a result of commit 5606e3877a ("mm: numa: Migrate on reference
policy"), /proc/<pid>/numa_maps prints the mempolicy for any <pid> as
"prefer:N" for the local node, N, of the process reading the file.
This should only be printed when the mempolicy of <pid> is
MPOL_PREFERRED for node N.
If the process is actually only using the default mempolicy for local
node allocation, make sure "default" is printed as expected.
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Robert Lippert <rlippert@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org> [3.7+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit a0c516cbfc ("zram: don't grab mutex in zram_slot_free_noity")
introduced free request pending code to avoid scheduling by mutex under
spinlock and it was a mess which made code lenghty and increased
overhead.
Now, we don't need zram->lock any more to free slot so this patch
reverts it and then, tb_lock should protect it.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, the zram table is protected by zram->lock but it's rather
coarse-grained lock and it makes hard for scalibility.
Let's use own rwlock instead of depending on zram->lock. This patch
adds new locking so obviously, it would make slow but this patch is just
prepartion for removing coarse-grained rw_semaphore(ie, zram->lock)
which is hurdle about zram scalability.
Final patch in this patchset series will remove the lock from read-path
and change rw_semaphore with mutex in write path. With bonus, we could
drop pending slot free mess in next patch.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit a0c516cbfc ("zram: don't grab mutex in zram_slot_free_noity")
introduced pending zram slot free in zram's write path in case of
missing slot free by memory allocation failure in zram_slot_free_notify
but it is not necessary because we have already freed the slot right
before overwriting.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergey reported we don't need to handle pending free request every I/O
so that this patch removes it in read path while we remain it in write
path.
Let's consider below example.
Swap subsystem ask to zram "A" block free by swap_slot_free_notify but
zram had been pended it without real freeing. Swap subsystem allocates
"A" block for new data but request pended for a long time just handled
and zram blindly free new data on the "A" block. :(
That's why we couldn't remove handle pending free request right before
zram-write.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan and Sergey reported that there is a racy between reset and flushing
of pending work so that it could make oops by freeing zram->meta in
reset while zram_slot_free can access zram->meta if new request is
adding during the race window.
This patch moves flush after taking init_lock so it prevents new request
so that it closes the race.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tAdd adds maintainer information for zsmalloc into the MAINTAINERS file.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add maintainer information for zram into the MAINTAINERS file.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add my copyright to the zsmalloc source code which I maintain.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add my copyright to the zram source code which I maintain.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the old private compcache project address so upcoming patches
should be sent to LKML because we Linux kernel community will take care.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zram has lived in staging for a LONG LONG time and have been
fixed/improved by many contributors so code is clean and stable now. Of
course, there are lots of product using zram in real practice.
The major TV companys have used zram as swap since two years ago and
recently our production team released android smart phone with zram
which is used as swap, too and recently Android Kitkat start to use zram
for small memory smart phone. And there was a report Google released
their ChromeOS with zram, too and cyanogenmod have been used zram long
time ago. And I heard some disto have used zram block device for tmpfs.
In addition, I saw many report from many other peoples. For example,
Lubuntu start to use it.
The benefit of zram is very clear. With my experience, one of the
benefit was to remove jitter of video application with backgroud memory
pressure. It would be effect of efficient memory usage by compression
but more issue is whether swap is there or not in the system. Recent
mobile platforms have used JAVA so there are many anonymous pages. But
embedded system normally are reluctant to use eMMC or SDCard as swap
because there is wear-leveling and latency issues so if we do not use
swap, it means we can't reclaim anoymous pages and at last, we could
encounter OOM kill. :(
Although we have real storage as swap, it was a problem, too. Because
it sometime ends up making system very unresponsible caused by slow swap
storage performance.
Quote from Luigi on Google
"Since Chrome OS was mentioned: the main reason why we don't use swap
to a disk (rotating or SSD) is because it doesn't degrade gracefully
and leads to a bad interactive experience. Generally we prefer to
manage RAM at a higher level, by transparently killing and restarting
processes. But we noticed that zram is fast enough to be competitive
with the latter, and it lets us make more efficient use of the
available RAM. " and he announced.
http://www.spinics.net/lists/linux-mm/msg57717.html
Other uses case is to use zram for block device. Zram is block device
so anyone can format the block device and mount on it so some guys on
the internet start zram as /var/tmp.
http://forums.gentoo.org/viewtopic-t-838198-start-0.html
Let's promote zram and enhance/maintain it instead of removing.
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Nitin Gupta <ngupta@vflare.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch moves zsmalloc under mm directory.
Before that, description will explain why we have needed custom
allocator.
Zsmalloc is a new slab-based memory allocator for storing compressed
pages. It is designed for low fragmentation and high allocation success
rate on large object, but <= PAGE_SIZE allocations.
zsmalloc differs from the kernel slab allocator in two primary ways to
achieve these design goals.
zsmalloc never requires high order page allocations to back slabs, or
"size classes" in zsmalloc terms. Instead it allows multiple
single-order pages to be stitched together into a "zspage" which backs
the slab. This allows for higher allocation success rate under memory
pressure.
Also, zsmalloc allows objects to span page boundaries within the zspage.
This allows for lower fragmentation than could be had with the kernel
slab allocator for objects between PAGE_SIZE/2 and PAGE_SIZE. With the
kernel slab allocator, if a page compresses to 60% of it original size,
the memory savings gained through compression is lost in fragmentation
because another object of the same size can't be stored in the leftover
space.
This ability to span pages results in zsmalloc allocations not being
directly addressable by the user. The user is given an
non-dereferencable handle in response to an allocation request. That
handle must be mapped, using zs_map_object(), which returns a pointer to
the mapped region that can be used. The mapping is necessary since the
object data may reside in two different noncontigious pages.
The zsmalloc fulfills the allocation needs for zram perfectly
[sjenning@linux.vnet.ibm.com: borrow Seth's quote]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Nitin Gupta <ngupta@vflare.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After commit 9a46ad6d6d ("smp: make smp_call_function_many() use logic
similar to smp_call_function_single()"), cfd->cpumask is accessed only
in smp_call_function_many(). So there is no more need to copy it into
cfd->cpumask_ipi before putting csd into the list. The cpumask_ipi
field is obsolete and can be removed.
Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Wang YanQing <udknight@gmail.com>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Cc: Shaohua Li <shli@fusionio.com>
Cc: 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>
Make smp_call_function_single and friends more efficient by using a
lockless list.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It is required to call put_device() if device_register() fails, so that
we give up the last reference to the device. Calling put_device allows
for mdiobus_release to be executed, kfreeing the bus.
Signed-off-by: Levente Kurusa <levex@linux.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: David Daney <david.daney@cavium.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently we kfree the container of the device which failed to register.
This is wrong as the last reference is not given up with a put_device
call. Also, now that we have put_device() callen, we no longer need the
kfree as the new_ld->dev.release function will take care of kfreeing the
associated memory.
Signed-off-by: Levente Kurusa <levex@linux.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now we have memblock_virt_alloc_low to replace original bootmem api in
swiotlb.
But we should not use BOOTMEM_LOW_LIMIT for arch that does not support
CONFIG_NOBOOTMEM, as old api take 0.
| #define alloc_bootmem_low(x) \
| __alloc_bootmem_low(x, SMP_CACHE_BYTES, 0)
|#define alloc_bootmem_low_pages_nopanic(x) \
| __alloc_bootmem_low_nopanic(x, PAGE_SIZE, 0)
and we have
#define BOOTMEM_LOW_LIMIT __pa(MAX_DMA_ADDRESS)
for CONFIG_NOBOOTMEM.
Restore goal to 0 to fix ia64 crash, that Tony found.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Reported-by: Tony Luck <tony.luck@gmail.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull block IO driver changes from Jens Axboe:
- bcache update from Kent Overstreet.
- two bcache fixes from Nicholas Swenson.
- cciss pci init error fix from Andrew.
- underflow fix in the parallel IDE pg_write code from Dan Carpenter.
I'm sure the 1 (or 0) users of that are now happy.
- two PCI related fixes for sx8 from Jingoo Han.
- floppy init fix for first block read from Jiri Kosina.
- pktcdvd error return miss fix from Julia Lawall.
- removal of IRQF_SHARED from the SEGA Dreamcast CD-ROM code from
Michael Opdenacker.
- comment typo fix for the loop driver from Olaf Hering.
- potential oops fix for null_blk from Raghavendra K T.
- two fixes from Sam Bradshaw (Micron) for the mtip32xx driver, fixing
an OOM problem and a problem with handling security locked conditions
* 'for-3.14/drivers' of git://git.kernel.dk/linux-block: (47 commits)
mg_disk: Spelling s/finised/finished/
null_blk: Null pointer deference problem in alloc_page_buffers
mtip32xx: Correctly handle security locked condition
mtip32xx: Make SGL container per-command to eliminate high order dma allocation
drivers/block/loop.c: fix comment typo in loop_config_discard
drivers/block/cciss.c:cciss_init_one(): use proper errnos
drivers/block/paride/pg.c: underflow bug in pg_write()
drivers/block/sx8.c: remove unnecessary pci_set_drvdata()
drivers/block/sx8.c: use module_pci_driver()
floppy: bail out in open() if drive is not responding to block0 read
bcache: Fix auxiliary search trees for key size > cacheline size
bcache: Don't return -EINTR when insert finished
bcache: Improve bucket_prio() calculation
bcache: Add bch_bkey_equal_header()
bcache: update bch_bkey_try_merge
bcache: Move insert_fixup() to btree_keys_ops
bcache: Convert sorting to btree_keys
bcache: Convert debug code to btree_keys
bcache: Convert btree_iter to struct btree_keys
bcache: Refactor bset_tree sysfs stats
...
Pull core block IO changes from Jens Axboe:
"The major piece in here is the immutable bio_ve series from Kent, the
rest is fairly minor. It was supposed to go in last round, but
various issues pushed it to this release instead. The pull request
contains:
- Various smaller blk-mq fixes from different folks. Nothing major
here, just minor fixes and cleanups.
- Fix for a memory leak in the error path in the block ioctl code
from Christian Engelmayer.
- Header export fix from CaiZhiyong.
- Finally the immutable biovec changes from Kent Overstreet. This
enables some nice future work on making arbitrarily sized bios
possible, and splitting more efficient. Related fixes to immutable
bio_vecs:
- dm-cache immutable fixup from Mike Snitzer.
- btrfs immutable fixup from Muthu Kumar.
- bio-integrity fix from Nic Bellinger, which is also going to stable"
* 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits)
xtensa: fixup simdisk driver to work with immutable bio_vecs
block/blk-mq-cpu.c: use hotcpu_notifier()
blk-mq: for_each_* macro correctness
block: Fix memory leak in rw_copy_check_uvector() handling
bio-integrity: Fix bio_integrity_verify segment start bug
block: remove unrelated header files and export symbol
blk-mq: uses page->list incorrectly
blk-mq: use __smp_call_function_single directly
btrfs: fix missing increment of bi_remaining
Revert "block: Warn and free bio if bi_end_io is not set"
block: Warn and free bio if bi_end_io is not set
blk-mq: fix initializing request's start time
block: blk-mq: don't export blk_mq_free_queue()
block: blk-mq: make blk_sync_queue support mq
block: blk-mq: support draining mq queue
dm cache: increment bi_remaining when bi_end_io is restored
block: fixup for generic bio chaining
block: Really silence spurious compiler warnings
block: Silence spurious compiler warnings
block: Kill bio_pair_split()
...
Pull nfsd updates from Bruce Fields:
- Handle some loose ends from the vfs read delegation support.
(For example nfsd can stop breaking leases on its own in a
fewer places where it can now depend on the vfs to.)
- Make life a little easier for NFSv4-only configurations
(thanks to Kinglong Mee).
- Fix some gss-proxy problems (thanks Jeff Layton).
- miscellaneous bug fixes and cleanup
* 'for-3.14' of git://linux-nfs.org/~bfields/linux: (38 commits)
nfsd: consider CLAIM_FH when handing out delegation
nfsd4: fix delegation-unlink/rename race
nfsd4: delay setting current_fh in open
nfsd4: minor nfs4_setlease cleanup
gss_krb5: use lcm from kernel lib
nfsd4: decrease nfsd4_encode_fattr stack usage
nfsd: fix encode_entryplus_baggage stack usage
nfsd4: simplify xdr encoding of nfsv4 names
nfsd4: encode_rdattr_error cleanup
nfsd4: nfsd4_encode_fattr cleanup
minor svcauth_gss.c cleanup
nfsd4: better VERIFY comment
nfsd4: break only delegations when appropriate
NFSD: Fix a memory leak in nfsd4_create_session
sunrpc: get rid of use_gssp_lock
sunrpc: fix potential race between setting use_gss_proxy and the upcall rpc_clnt
sunrpc: don't wait for write before allowing reads from use-gss-proxy file
nfsd: get rid of unused function definition
Define op_iattr for nfsd4_open instead using macro
NFSD: fix compile warning without CONFIG_NFSD_V3
...
Fix
drivers/char/ipmi/ipmi_si_intf.c: In function 'ipmi_parisc_probe':
drivers/char/ipmi/ipmi_si_intf.c:2752:2: error: 'rv' undeclared (first use in this function)
drivers/char/ipmi/ipmi_si_intf.c:2752:2: note: each undeclared identifier is reported only once for each function it appears in
Introduced by commit d02b3709ff ("ipmi: Cleanup error return")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chris Mason reported a NULL pointer derefernence in generic_getxattr()
that was due to sb->s_xattr being NULL.
The reason is that the nfs #ifdef's for ACL support were misplaced, and
the nfs3 inode operations had the xattr operation pointers set up, even
though xattrs were not actually supported. As a result, the xattr code
was being called without the infrastructure having been set up.
Move the #ifdef's appropriately.
Reported-and-tested-by: Chris Mason <clm@fb.com>
Acked-by: Al Viro viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both clang 3.5 and GCC 4.9 will support this (as of r199754 and r207196
respectively). Both have been tested to produce booting kernels when the
16-bit code is built with -m16. (Modulo LLVM PR3997, at least.)
[ hpa: folded test for -m16 into M16_CFLAGS ]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1390997807.20153.133.camel@i7.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Commit dd78b97367 ("x86, boot: Move CPU
flags out of cpucheck") introduced ambiguous inline asm in the
has_eflag() function. In 16-bit mode want the instruction to be
'pushfl', but we just say 'pushf' and hope the compiler does what we
wanted.
When building with 'clang -m16', it won't, because clang doesn't use
the horrid '.code16gcc' hack that even 'gcc -m16' uses internally.
Say what we mean and don't make the compiler make assumptions.
[ hpa: ideally we would be able to use the gcc %zN construct here, but
that is broken for 64-bit integers in gcc < 4.5.
The code with plain "pushf/popf" is fine for 32- or 64-bit mode, but
not for 16-bit mode; in 16-bit mode those are 16-bit instructions in
.code16 mode, and 32-bit instructions in .code16gcc mode. ]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1391079628.26079.82.camel@shinybook.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
So any FIQ handling is superfluous at the moment. The functions to
disable/enable FIQs is kept around if ever someone needs them in the
future, but existing calling sites including arch_cpu_idle_prepare()
may go for now.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
On ARM, address size can be 32 bits or 64 bits (if CONFIG_ARCH_PHYS_ADDR_T_64BIT
is enabled).
We can't assume that the grant frame base address will always fits in an
unsigned long. Use phys_addr_t instead of unsigned long as argument for
gnttab_setup_auto_xlat_frames.
Signed-off-by: Julien Grall <julien.grall@linaro.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
The use of phys_to_machine and machine_to_phys in the phys<=>bus conversions
causes us to lose the top bits of the DMA address if the size of a DMA address is not the same as the size of the phyiscal address.
This can happen in practice on ARM where foreign pages can be above 4GB even
though the local kernel does not have LPAE page tables enabled (which is
totally reasonable if the guest does not itself have >4GB of RAM). In this
case the kernel still maps the foreign pages at a phys addr below 4G (as it
must) but the resulting DMA address (returned by the grant map operation) is
much higher.
This is analogous to a hardware device which has its view of RAM mapped up
high for some reason.
This patch makes I/O to foreign pages (specifically blkif) work on 32-bit ARM
systems with more than 4GB of RAM.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Linus Torvalds