kexec: verify the signature of signed PE bzImage

This is the final piece of the puzzle of verifying kernel image signature
during kexec_file_load() syscall.

This patch calls into PE file routines to verify signature of bzImage.  If
signature are valid, kexec_file_load() succeeds otherwise it fails.

Two new config options have been introduced.  First one is
CONFIG_KEXEC_VERIFY_SIG.  This option enforces that kernel has to be
validly signed otherwise kernel load will fail.  If this option is not
set, no signature verification will be done.  Only exception will be when
secureboot is enabled.  In that case signature verification should be
automatically enforced when secureboot is enabled.  But that will happen
when secureboot patches are merged.

Second config option is CONFIG_KEXEC_BZIMAGE_VERIFY_SIG.  This option
enables signature verification support on bzImage.  If this option is not
set and previous one is set, kernel image loading will fail because kernel
does not have support to verify signature of bzImage.

I tested these patches with both "pesign" and "sbsign" signed bzImages.

I used signing_key.priv key and signing_key.x509 cert for signing as
generated during kernel build process (if module signing is enabled).

Used following method to sign bzImage.

pesign
======
- Convert DER format cert to PEM format cert
openssl x509 -in signing_key.x509 -inform DER -out signing_key.x509.PEM -outform
PEM

- Generate a .p12 file from existing cert and private key file
openssl pkcs12 -export -out kernel-key.p12 -inkey signing_key.priv -in
signing_key.x509.PEM

- Import .p12 file into pesign db
pk12util -i /tmp/kernel-key.p12 -d /etc/pki/pesign

- Sign bzImage
pesign -i /boot/vmlinuz-3.16.0-rc3+ -o /boot/vmlinuz-3.16.0-rc3+.signed.pesign
-c "Glacier signing key - Magrathea" -s

sbsign
======
sbsign --key signing_key.priv --cert signing_key.x509.PEM --output
/boot/vmlinuz-3.16.0-rc3+.signed.sbsign /boot/vmlinuz-3.16.0-rc3+

Patch details:

Well all the hard work is done in previous patches.  Now bzImage loader
has just call into that code and verify whether bzImage signature are
valid or not.

Also create two config options.  First one is CONFIG_KEXEC_VERIFY_SIG.
This option enforces that kernel has to be validly signed otherwise kernel
load will fail.  If this option is not set, no signature verification will
be done.  Only exception will be when secureboot is enabled.  In that case
signature verification should be automatically enforced when secureboot is
enabled.  But that will happen when secureboot patches are merged.

Second config option is CONFIG_KEXEC_BZIMAGE_VERIFY_SIG.  This option
enables signature verification support on bzImage.  If this option is not
set and previous one is set, kernel image loading will fail because kernel
does not have support to verify signature of bzImage.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: support kexec/kdump on EFI systems

This patch does two things.  It passes EFI run time mappings to second
kernel in bootparams efi_info.  Second kernel parse this info and create
new mappings in second kernel.  That means mappings in first and second
kernel will be same.  This paves the way to enable EFI in kexec kernel.

This patch also prepares and passes EFI setup data through bootparams.
This contains bunch of information about various tables and their
addresses.

These information gathering and passing has been written along the lines
of what current kexec-tools is doing to make kexec work with UEFI.

[akpm@linux-foundation.org: s/get_efi/efi_get/g, per Matt]
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: support for kexec on panic using new system call

This patch adds support for loading a kexec on panic (kdump) kernel usning
new system call.

It prepares ELF headers for memory areas to be dumped and for saved cpu
registers.  Also prepares the memory map for second kernel and limits its
boot to reserved areas only.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec-bzImage64: support for loading bzImage using 64bit entry

This is loader specific code which can load bzImage and set it up for
64bit entry.  This does not take care of 32bit entry or real mode entry.

32bit mode entry can be implemented if somebody needs it.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: load and relocate purgatory at kernel load time

Load purgatory code in RAM and relocate it based on the location.
Relocation code has been inspired by module relocation code and purgatory
relocation code in kexec-tools.

Also compute the checksums of loaded kexec segments and store them in
purgatory.

Arch independent code provides this functionality so that arch dependent
bootloaders can make use of it.

Helper functions are provided to get/set symbol values in purgatory which
are used by bootloaders later to set things like stack and entry point of
second kernel etc.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

purgatory: core purgatory functionality

Create a stand alone relocatable object purgatory which runs between two
kernels.  This name, concept and some code has been taken from
kexec-tools.  Idea is that this code runs after a crash and it runs in
minimal environment.  So keep it separate from rest of the kernel and in
long term we will have to practically do no maintenance of this code.

This code also has the logic to do verify sha256 hashes of various
segments which have been loaded into memory.  So first we verify that the
kernel we are jumping to is fine and has not been corrupted and make
progress only if checsums are verified.

This code also takes care of copying some memory contents to backup region.

[sfr@canb.auug.org.au: run host built programs from objtree]
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

purgatory/sha256: provide implementation of sha256 in purgaotory context

Next two patches provide code for purgatory.  This is a code which does
not link against the kernel and runs stand alone.  This code runs between
two kernels.  One of the primary purpose of this code is to verify the
digest of newly loaded kernel and making sure it matches the digest
computed at kernel load time.

We use sha256 for calculating digest of kexec segmetns.  Purgatory can't
use stanard crypto API as that API is not available in purgatory context.

Hence, I have copied code from crypto/sha256_generic.c and compiled it
with purgaotry code so that it could be used.  I could not #include
sha256_generic.c file here as some of the function signature requiered
little tweaking.  Original functions work with crypto API but these ones
don't

So instead of doing #include on sha256_generic.c I just copied relevant
portions of code into arch/x86/purgatory/sha256.c.  Now we shouldn't have
to touch this code at all.  Do let me know if there are better ways to
handle it.

This patch does not enable compiling of this code.  That happens in next
patch.  I wanted to highlight this change in a separate patch for easy
review.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: implementation of new syscall kexec_file_load

Previous patch provided the interface definition and this patch prvides
implementation of new syscall.

Previously segment list was prepared in user space.  Now user space just
passes kernel fd, initrd fd and command line and kernel will create a
segment list internally.

This patch contains generic part of the code.  Actual segment preparation
and loading is done by arch and image specific loader.  Which comes in
next patch.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: new syscall kexec_file_load() declaration

This is the new syscall kexec_file_load() declaration/interface.  I have
reserved the syscall number only for x86_64 so far.  Other architectures
(including i386) can reserve syscall number when they enable the support
for this new syscall.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: make kexec_segment user buffer pointer a union

So far kexec_segment->buf was always a user space pointer as user space
passed the array of kexec_segment structures and kernel copied it.

But with new system call, list of kexec segments will be prepared by
kernel and kexec_segment->buf will point to a kernel memory.

So while I was adding code where I made assumption that ->buf is pointing
to kernel memory, sparse started giving warning.

Make ->buf a union.  And where a user space pointer is expected, access it
using ->buf and where a kernel space pointer is expected, access it using
->kbuf.  That takes care of sparse warnings.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

resource: provide new functions to walk through resources

I have added two more functions to walk through resources.

Currently walk_system_ram_range() deals with pfn and /proc/iomem can
contain partial pages.  By dealing in pfn, callback function loses the
info that last page of a memory range is a partial page and not the full
page.  So I implemented walk_system_ram_res() which returns u64 values to
callback functions and now it properly return start and end address.

walk_system_ram_range() uses find_next_system_ram() to find the next ram
resource.  This in turn only travels through siblings of top level child
and does not travers through all the nodes of the resoruce tree.  I also
need another function where I can walk through all the resources, for
example figure out where "GART" aperture is.  Figure out where ACPI memory
is.

So I wrote another function walk_iomem_res() which walks through all
/proc/iomem resources and returns matches as asked by caller.  Caller can
specify "name" of resource, start and end and flags.

Got rid of find_next_system_ram_res() and instead implemented more generic
find_next_iomem_res() which can be used to traverse top level children
only based on an argument.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: use common function for kimage_normal_alloc() and kimage_crash_alloc()

kimage_normal_alloc() and kimage_crash_alloc() are doing lot of similar
things and differ only little.  So instead of having two separate
functions create a common function kimage_alloc_init() and pass it the
"flags" argument which tells whether it is normal kexec or kexec_on_panic.
 And this function should be able to deal with both the cases.

This consolidation also helps later where we can use a common function
kimage_file_alloc_init() to handle normal and crash cases for new file
based kexec syscall.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: move segment verification code in a separate function

Previously do_kimage_alloc() will allocate a kimage structure, copy
segment list from user space and then do the segment list sanity
verification.

Break down this function in 3 parts.  do_kimage_alloc_init() to do actual
allocation and basic initialization of kimage structure.
copy_user_segment_list() to copy segment list from user space and
sanity_check_segment_list() to verify the sanity of segment list as passed
by user space.

In later patches, I need to only allocate kimage and not copy segment list
from user space.  So breaking down in smaller functions enables re-use of
code at other places.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kexec: rename unusebale_pages to unusable_pages

Let's use the more common "unusable".

This patch was originally written and posted by Boris. I am including it
in this patch series.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel: build bin2c based on config option CONFIG_BUILD_BIN2C

currently bin2c builds only if CONFIG_IKCONFIG=y. But bin2c will now be
used by kexec too.  So make it compilation dependent on CONFIG_BUILD_BIN2C
and this config option can be selected by CONFIG_KEXEC and CONFIG_IKCONFIG.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

bin2c: move bin2c in scripts/basic

This patch series does not do kernel signature verification yet.  I plan
to post another patch series for that.  Now distributions are already
signing PE/COFF bzImage with PKCS7 signature I plan to parse and verify
those signatures.

Primary goal of this patchset is to prepare groundwork so that kernel
image can be signed and signatures be verified during kexec load.  This
should help with two things.

- It should allow kexec/kdump on secureboot enabled machines.

- In general it can help even without secureboot. By being able to verify
  kernel image signature in kexec, it should help with avoiding module
  signing restrictions. Matthew Garret showed how to boot into a custom
  kernel, modify first kernel's memory and then jump back to old kernel and
  bypass any policy one wants to.

This patch (of 15):

Kexec wants to use bin2c and it wants to use it really early in the build
process. See arch/x86/purgatory/ code in later patches.

So move bin2c in scripts/basic so that it can be built very early and
be usable by arch/x86/purgatory/

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: WANG Chao <chaowang@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

shm: wait for pins to be released when sealing

If we set SEAL_WRITE on a file, we must make sure there cannot be any
ongoing write-operations on the file.  For write() calls, we simply lock
the inode mutex, for mmap() we simply verify there're no writable
mappings.  However, there might be pages pinned by AIO, Direct-IO and
similar operations via GUP.  We must make sure those do not write to the
memfd file after we set SEAL_WRITE.

As there is no way to notify GUP users to drop pages or to wait for them
to be done, we implement the wait ourself: When setting SEAL_WRITE, we
check all pages for their ref-count.  If it's bigger than 1, we know
there's some user of the page.  We then mark the page and wait for up to
150ms for those ref-counts to be dropped.  If the ref-counts are not
dropped in time, we refuse the seal operation.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests: add memfd/sealing page-pinning tests

Setting SEAL_WRITE is not possible if there're pending GUP users. This
commit adds selftests for memfd+sealing that use FUSE to create pending
page-references. FUSE is very helpful here in that it allows us to delay
direct-IO operations for an arbitrary amount of time. This way, we can
force the kernel to pin pages and then run our normal selftests.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

selftests: add memfd_create() + sealing tests

Some basic tests to verify sealing on memfds works as expected and
guarantees the advertised semantics.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

shm: add memfd_create() syscall

memfd_create() is similar to mmap(MAP_ANON), but returns a file-descriptor
that you can pass to mmap().  It can support sealing and avoids any
connection to user-visible mount-points.  Thus, it's not subject to quotas
on mounted file-systems, but can be used like malloc()'ed memory, but with
a file-descriptor to it.

memfd_create() returns the raw shmem file, so calls like ftruncate() can
be used to modify the underlying inode.  Also calls like fstat() will
return proper information and mark the file as regular file.  If you want
sealing, you can specify MFD_ALLOW_SEALING.  Otherwise, sealing is not
supported (like on all other regular files).

Compared to O_TMPFILE, it does not require a tmpfs mount-point and is not
subject to a filesystem size limit.  It is still properly accounted to
memcg limits, though, and to the same overcommit or no-overcommit
accounting as all user memory.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

shm: add sealing API

If two processes share a common memory region, they usually want some
guarantees to allow safe access. This often includes:
  - one side cannot overwrite data while the other reads it
  - one side cannot shrink the buffer while the other accesses it
  - one side cannot grow the buffer beyond previously set boundaries

If there is a trust-relationship between both parties, there is no need
for policy enforcement.  However, if there's no trust relationship (eg.,
for general-purpose IPC) sharing memory-regions is highly fragile and
often not possible without local copies.  Look at the following two
use-cases:

  1) A graphics client wants to share its rendering-buffer with a
     graphics-server. The memory-region is allocated by the client for
     read/write access and a second FD is passed to the server. While
     scanning out from the memory region, the server has no guarantee that
     the client doesn't shrink the buffer at any time, requiring rather
     cumbersome SIGBUS handling.
  2) A process wants to perform an RPC on another process. To avoid huge
     bandwidth consumption, zero-copy is preferred. After a message is
     assembled in-memory and a FD is passed to the remote side, both sides
     want to be sure that neither modifies this shared copy, anymore. The
     source may have put sensible data into the message without a separate
     copy and the target may want to parse the message inline, to avoid a
     local copy.

While SIGBUS handling, POSIX mandatory locking and MAP_DENYWRITE provide
ways to achieve most of this, the first one is unproportionally ugly to
use in libraries and the latter two are broken/racy or even disabled due
to denial of service attacks.

This patch introduces the concept of SEALING.  If you seal a file, a
specific set of operations is blocked on that file forever.  Unlike locks,
seals can only be set, never removed.  Hence, once you verified a specific
set of seals is set, you're guaranteed that no-one can perform the blocked
operations on this file, anymore.

An initial set of SEALS is introduced by this patch:
  - SHRINK: If SEAL_SHRINK is set, the file in question cannot be reduced
            in size. This affects ftruncate() and open(O_TRUNC).
  - GROW: If SEAL_GROW is set, the file in question cannot be increased
          in size. This affects ftruncate(), fallocate() and write().
  - WRITE: If SEAL_WRITE is set, no write operations (besides resizing)
           are possible. This affects fallocate(PUNCH_HOLE), mmap() and
           write().
  - SEAL: If SEAL_SEAL is set, no further seals can be added to a file.
          This basically prevents the F_ADD_SEAL operation on a file and
          can be set to prevent others from adding further seals that you
          don't want.

The described use-cases can easily use these seals to provide safe use
without any trust-relationship:

  1) The graphics server can verify that a passed file-descriptor has
     SEAL_SHRINK set. This allows safe scanout, while the client is
     allowed to increase buffer size for window-resizing on-the-fly.
     Concurrent writes are explicitly allowed.
  2) For general-purpose IPC, both processes can verify that SEAL_SHRINK,
     SEAL_GROW and SEAL_WRITE are set. This guarantees that neither
     process can modify the data while the other side parses it.
     Furthermore, it guarantees that even with writable FDs passed to the
     peer, it cannot increase the size to hit memory-limits of the source
     process (in case the file-storage is accounted to the source).

The new API is an extension to fcntl(), adding two new commands:
  F_GET_SEALS: Return a bitset describing the seals on the file. This
               can be called on any FD if the underlying file supports
               sealing.
  F_ADD_SEALS: Change the seals of a given file. This requires WRITE
               access to the file and F_SEAL_SEAL may not already be set.
               Furthermore, the underlying file must support sealing and
               there may not be any existing shared mapping of that file.
               Otherwise, EBADF/EPERM is returned.
               The given seals are _added_ to the existing set of seals
               on the file. You cannot remove seals again.

The fcntl() handler is currently specific to shmem and disabled on all
files. A file needs to explicitly support sealing for this interface to
work. A separate syscall is added in a follow-up, which creates files that
support sealing. There is no intention to support this on other
file-systems. Semantics are unclear for non-volatile files and we lack any
use-case right now. Therefore, the implementation is specific to shmem.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm: allow drivers to prevent new writable mappings

This patch (of 6):

The i_mmap_writable field counts existing writable mappings of an
address_space.  To allow drivers to prevent new writable mappings, make
this counter signed and prevent new writable mappings if it is negative.
This is modelled after i_writecount and DENYWRITE.

This will be required by the shmem-sealing infrastructure to prevent any
new writable mappings after the WRITE seal has been set.  In case there
exists a writable mapping, this operation will fail with EBUSY.

Note that we rely on the fact that iff you already own a writable mapping,
you can increase the counter without using the helpers.  This is the same
that we do for i_writecount.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: remove unused NFSD pattern

A series of commits by Christoph Hellwig removed all the files in this
directory, remove the pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: remove unusd ARM/QUALCOMM MSM pattern

Commit 87933a68dce6 ("mfd: pm8921: Remove pm8xxx API now that
sub-devices use regmap") removed the file, remove the pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: remove unused radeon drm pattern

Commit 8dcedd7e87f4 ("UAPI: (Scripted) Disintegrate include/drm") moved
the file, remove the pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: remove METAG imgdafs pattern

This never made it into the kernel tree.  Remove it.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: remove section CIRRUS LOGIC EP93XX OHCI USB HOST DRIVER

Commit e55f7cd24676 ("usb: ohci: remove ep93xx bus glue platform
driver") removed the file, remove the section.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: H Hartley Sweeten <hartleys@visionengravers.com>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update picoxcell patterns

Fix the picoxcell patterns, add the dts directory too.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: fix PXA3xx NAND FLASH DRIVER pattern

Use underscore, not dash

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: use correct filename for sdhci-bcm-kona

Use dashes not underscores.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Christian Daudt <csd@broadcom.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: fix ssbi pattern

Incorrect pattern used, it's not a directory, it's a file.  Fix it.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update clk/sirf patterns

Commit 7bf21bc81f28 ("clk: sirf: re-arch to make the codes support both
prima2 and atlas6") moved the files, update the patterns.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: use the correct efi-stub location

Commit 4171fe2f8a47 ("EFI stub documentation updates") moved the file,
update the pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update cifs location

Commit 30706a545417 ("cifs: create a new Documentation/ directory and
move docfiles into it") moved the files, update the pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update microcode patterns

Commit bad5fa631fca ("x86, microcode: Move to a proper location") moved
the files, update the pattern.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/net/ethernet/amd/pcnet32.c: neaten and remove unnecessary OOM messages

Make the code flow a little better for 80 columns.

Use a consistent style for the RX and TX rings allocation.
Use BIT macro.
Use a temporary unsiged int entries for (1<<size).
Remove the OOM messages as they duplicate the generic
OOM and dump_stack() provided by the memory subsystem.
Reflow allocs to 80 columns.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Don Fry <pcnet32@frontier.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vme: bridges: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Martyn Welch <martyn.welch@ge.com>
Cc: Manohar Vanga <manohar.vanga@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

synclink_gt: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

staging: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Lior Dotan <liodot@gmail.com>
Cc: Christopher Harrer <charrer@alacritech.com>
Cc: Forest Bond <forest@alittletooquiet.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scsi: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Adam Radford <linuxraid@lsi.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Jayamohan Kallickal <jayamohan.kallickal@emulex.com>
Cc: Dario Ballabio <ballabio_dario@emc.com>
Cc: Michael Neuffer <mike@i-Connect.Net>
Cc: "Stephen M. Cameron" <scameron@beardog.cce.hp.com>
Cc: Neela Syam Kolli <megaraidlinux@lsi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtlwifi: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Chaoming Li <chaoming_li@realsil.com.cn>
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>

rtl818x: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
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>

mwl8k: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Lennert Buytenhek <buytenh@wantstofly.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>

ipw2100: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Stanislav Yakovlev <stas.yakovlev@gmail.com>
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>

irda: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Samuel Ortiz <samuel@sortiz.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

qlogic: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Manish Chopra <manish.chopra@qlogic.com>
Cc: Sony Chacko <sony.chacko@qlogic.com>
Cc: Rajesh Borundia <rajesh.borundia@qlogic.com>
Cc: Shahed Shaikh <shahed.shaikh@qlogic.com>
Cc: Jitendra Kalsaria <jitendra.kalsaria@qlogic.com>
Cc: Ron Mercer <ron.mercer@qlogic.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

micrel: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sky2: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Mirko Lindner <mlindner@marvell.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

enic: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Christian Benvenuti <benve@cisco.com>
Cc: Sujith Sankar <ssujith@cisco.com>
Cc: Govindarajulu Varadarajan <_govind@gmx.com>
Cc: Neel Patel <neepatel@cisco.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

atl1e: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

amd: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Don Fry <pcnet32@frontier.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

media: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

i810: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

infiniband: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: Faisal Latif <faisal.latif@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

crypto: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

block: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Mike Miller <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

atm: use pci_zalloc_consistent

Remove the now unnecessary memset too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Chas Williams <chas@cmf.nrl.navy.mil>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

pci-dma-compat: add pci_zalloc_consistent helper

Add this helper for consistency with pci_zalloc_coherent
and the ability to remove unnecessary memset(,0,) uses.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: "Stephen M. Cameron" <scameron@beardog.cce.hp.com>
Cc: Adam Radford <linuxraid@lsi.com>
Cc: Chaoming Li <chaoming_li@realsil.com.cn>
Cc: Chas Williams <chas@cmf.nrl.navy.mil>
Cc: Christian Benvenuti <benve@cisco.com>
Cc: Christopher Harrer <charrer@alacritech.com>
Cc: Dario Ballabio <ballabio_dario@emc.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Don Fry <pcnet32@frontier.com>
Cc: Faisal Latif <faisal.latif@intel.com>
Cc: Forest Bond <forest@alittletooquiet.net>
Cc: Govindarajulu Varadarajan <_govind@gmx.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Jayamohan Kallickal <jayamohan.kallickal@emulex.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Jitendra Kalsaria <jitendra.kalsaria@qlogic.com>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Lennert Buytenhek <buytenh@wantstofly.org>
Cc: Lior Dotan <liodot@gmail.com>
Cc: Manish Chopra <manish.chopra@qlogic.com>
Cc: Manohar Vanga <manohar.vanga@gmail.com>
Cc: Martyn Welch <martyn.welch@ge.com>
Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
Cc: Michael Neuffer <mike@i-Connect.Net>
Cc: Mirko Lindner <mlindner@marvell.com>
Cc: Neel Patel <neepatel@cisco.com>
Cc: Neela Syam Kolli <megaraidlinux@lsi.com>
Cc: Rajesh Borundia <rajesh.borundia@qlogic.com>
Cc: Roland Dreier <roland@kernel.org>
Cc: Ron Mercer <ron.mercer@qlogic.com>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Shahed Shaikh <shahed.shaikh@qlogic.com>
Cc: Sony Chacko <sony.chacko@qlogic.com>
Cc: Stanislav Yakovlev <stas.yakovlev@gmail.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Steve Wise <swise@opengridcomputing.com>
Cc: Sujith Sankar <ssujith@cisco.com>
Cc: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/scsi: replace strict_strto calls

Replace obsolete strict_strto with more appropriate kstrto calls

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86: replace strict_strto calls

Replace obsolete strict_strto calls with appropriate kstrto calls

Signed-off-by: Daniel Walter <dwalter@google.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/powerpc: replace obsolete strict_strto* calls

Replace strict_strto calls with more appropriate kstrto calls

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mach-w90x900/cpu.c: replace obsolete strict_strto

Replace obsolete strict_strto with kstrto calls

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mach-s3c24xx/mach-jive.c: replace strict_strto* with kstrto*

Replace obsolete strict_strto call with kstrto

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mach-pxa: replace strict_strto call with kstrto

Replace obsolete call to strict_strto with kstrto

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mach-omap2: replace strict_strto* with kstrto*

Replace obsolete strict_strto call with kstrto calls.
Simplify copy_from_user/strict_strto by using kstrto_from_user

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: update IBM ServeRAID RAID info

- Invalid maintainer e-mail address:
  Mail server reply:
  Recipient address rejected: User unknown in virtual alias table
- Remove no longer working webpage URL
- Remove obsolete "Person" field
- Move status to "Orphan"
- Add Dave Jeffery and Jack Hammer to the CREDITS file

Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Cc: David Jeffery <dhjeffery@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Reviewed-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>

MAINTAINERS: remove two ancient EATA sections

These haven't had a single ack by the listed maintainer in all git history
and the email addresses don't work.

An EATA entry for Michael Neuffer is already in CREDITS.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

update Roland McGrath's mail

roland@redhat.com bounces, change it to roland@hack.frob.com.

Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Roland McGrath <roland@hack.frob.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init/main.c: code clean-up

Fixing some checkpatch warnings(remove global initialization, move
__initdata, coalesce formats ...)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/acct.c: fix coding style warnings and errors

Signed-off-by: Ionut Alexa <ionut.m.alexa@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arm64,ia64,ppc,s390,sh,tile,um,x86,mm: remove default gate area

The core mm code will provide a default gate area based on
FIXADDR_USER_START and FIXADDR_USER_END if
!defined(__HAVE_ARCH_GATE_AREA) && defined(AT_SYSINFO_EHDR).

This default is only useful for ia64.  arm64, ppc, s390, sh, tile, 64-bit
UML, and x86_32 have their own code just to disable it.  arm, 32-bit UML,
and x86_64 have gate areas, but they have their own implementations.

This gets rid of the default and moves the code into ia64.

This should save some code on architectures without a gate area: it's now
possible to inline the gate_area functions in the default case.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [in principle]
Acked-by: Richard Weinberger <richard@nod.at> [for um]
Acked-by: Will Deacon <will.deacon@arm.com> [for arm64]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/dlm/debug_fs.c: remove unnecessary null test before debugfs_remove

This fixes checkpatch warning:

  WARNING: debugfs_remove(NULL) is safe this check is probably not required

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/checkstack.pl: automatically handle 32-bit and 64-bit mode for ARCH=x86

This patch adds support for ARCH=x86 into checkstack.

Commit ffee0de411fd ("x86: Default to ARCH=x86 to avoid overriding
CONFIG_64BIT") had merged ARCH=i386 and ARCH=x86_64 into one ARCH=x86.
checkstack.pl searches patterns of machine instructions which are
usually used for allocating stack frames.  checkstalk.pl needs either
i386 or x86_64, x86 isn't enough:

  $ make checkstack
  objdump -d vmlinux $(find . -name '*.ko') | \
  perl linux/scripts/checkstack.pl x86
  wrong or unknown architecture "x86"

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/tags.sh: include compat_sys_* symbols in the generated tags

Since the kernel now has a COMPAT_SYSCALL infrastructure via commit
468366138850 ("COMPAT_SYSCALL_DEFINE: infrastructure"), add the
corresponding regex for generating compat_sys_* symbols in the tags
files (similar to sys_*).

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/coccinelle/free/ifnullfree.cocci: add copyright information

All coccinelle scripts have a copyright in the header.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Suggested-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

scripts/coccinelle/free: add NULL test before freeing functions

Warns or generates patch for NULL check before the following functions:

kfree
usb_free_urb
debugfs_remove
debugfs_remove_recursive

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Gilles Muller <Gilles.Muller@lip6.fr>
Cc: Joe Perches <joe@perches.com>
Cc: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/scatterlist: clean up useless architecture versions of scatterlist.h

There's no need to have an architecture version of scatterlist.h if the
only thing the file does is include asm-generic/scatterlist.h.  Switch to
the asm-generic versions directly.

Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Chen Liqin <liqin.linux@gmail.com>,
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/scatterlist: make ARCH_HAS_SG_CHAIN an actual Kconfig

Rather than have architectures #define ARCH_HAS_SG_CHAIN in an
architecture specific scatterlist.h, make it a proper Kconfig option and
use that instead.  At same time, remove the header files are are now
mostly useless and just include asm-generic/scatterlist.h.

[sfr@canb.auug.org.au: powerpc files now need asm/dma.h]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [powerpc]
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

shm: remove unneeded extern for function

A small cleanup while changing adjacent code.  Extern is not needed for
functions and only one declaration had it so remove it from the odd line.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Jack Miller <millerjo@us.ibm.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

shm: allow exit_shm in parallel if only marking orphans

If shm_rmid_force (the default state) is not set then the shmids are only
marked as orphaned and does not require any add, delete, or locking of the
tree structure.

Seperate the sysctl on and off case, and only obtain the read lock.  The
newly added list head can be deleted under the read lock because we are
only called with current and will only change the semids allocated by this
task and not manipulate the list.

This commit assumes that up_read includes a sufficient memory barrier for
the writes to be seen my others that later obtain a write lock.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Jack Miller <millerjo@us.ibm.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

shm: make exit_shm work proportional to task activity

This is small set of patches our team has had kicking around for a few
versions internally that fixes tasks getting hung on shm_exit when there
are many threads hammering it at once.

Anton wrote a simple test to cause the issue:

  http://ozlabs.org/~anton/junkcode/bust_shm_exit.c

Before applying this patchset, this test code will cause either hanging
tracebacks or pthread out of memory errors.

After this patchset, it will still produce output like:

  root@somehost:~# ./bust_shm_exit 1024 160
  ...
  INFO: rcu_sched detected stalls on CPUs/tasks: {} (detected by 116, t=2111 jiffies, g=241, c=240, q=7113)
  INFO: Stall ended before state dump start
  ...

But the task will continue to run along happily, so we consider this an
improvement over hanging, even if it's a bit noisy.

This patch (of 3):

exit_shm obtains the ipc_ns shm rwsem for write and holds it while it
walks every shared memory segment in the namespace.  Thus the amount of
work is related to the number of shm segments in the namespace not the
number of segments that might need to be cleaned.

In addition, this occurs after the task has been notified the thread has
exited, so the number of tasks waiting for the ns shm rwsem can grow
without bound until memory is exausted.

Add a list to the task struct of all shmids allocated by this task.  Init
the list head in copy_process.  Use the ns->rwsem for locking.  Add
segments after id is added, remove before removing from id.

On unshare of NEW_IPCNS orphan any ids as if the task had exited, similar
to handling of semaphore undo.

I chose a define for the init sequence since its a simple list init,
otherwise it would require a function call to avoid include loops between
the semaphore code and the task struct.  Converting the list_del to
list_del_init for the unshare cases would remove the exit followed by
init, but I left it blow up if not inited.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Jack Miller <millerjo@us.ibm.com>
Cc: Davidlohr Bueso <davidlohr@hp.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

initramfs: add write error checks

On a system with low memory extracting the initramfs may fail.  If this
happens the user gets "Failed to execute /init" instead of an initramfs
error.

Check return value of sys_write and call error() when the write was
incomplete or failed.

Signed-off-by: David Engraf <david.engraf@sysgo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

initramfs: support initramfs that is bigger than 2GiB

Now with 64bit bzImage and kexec tools, we support ramdisk that size is
bigger than 2g, as we could put it above 4G.

Found compressed initramfs image could not be decompressed properly.  It
turns out that image length is int during decompress detection, and it
will become < 0 when length is more than 2G.  Furthermore, during
decompressing len as int is used for inbuf count, that has problem too.

Change len to long, that should be ok as on 32 bit platform long is
32bits.

Tested with following compressed initramfs image as root with kexec.
gzip, bzip2, xz, lzma, lzop, lz4.
run time for populate_rootfs():
   size        name       Nehalem-EX  Westmere-EX  Ivybridge-EX
 9034400256 root_img     :   26s           24s          30s
 3561095057 root_img.lz4 :   28s           27s          27s
 3459554629 root_img.lzo :   29s           29s          28s
 3219399480 root_img.gz  :   64s           62s          49s
 2251594592 root_img.xz  :  262s          260s         183s
 2226366598 root_img.lzma:  386s          376s         277s
 2901482513 root_img.bz2 :  635s          599s

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Rashika Kheria <rashika.kheria@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: P J P <ppandit@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: "Daniel M. Weeks" <dan@danweeks.net>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

initramfs: support initrd that is bigger than 2GiB

When initrd (compressed or not) is used, kernel report data corrupted with
/dev/ram0.

The root cause:
During initramfs checking, if it is initrd, it will be transferred to
/initrd.image with sys_write.
sys_write only support 2G-4K write, so if the initrd ram is more than
that, /initrd.image will not complete at all.

Add local xwrite to loop calling sys_write to workaround the problem.

Also need to use xwrite in write_buffer() to handle:
image is uncompressed cpio and there is one big file (>2G) in it.
   unpack_to_rootfs ===> write_buffer ===> actions[]/do_copy

At the same time, we don't need to worry about sys_read/sys_write in
do_mounts_rd.c::crd_load.  As decompressor will have fill/flush and local
buffer that is smaller than 2G.

Test with uncompressed initrd, and compressed ones with gz, bz2, lzma,xz,
lzop.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: "Daniel M. Weeks" <dan@danweeks.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

initrd: fix lz4 decompress with initrd

During testing initrd (>2G) support, find decompress/lz4 does not work
with initrd at all.

decompress_* should support:
1. inbuf[]/outbuf[] for kernel preboot.
2. inbuf[]/flush() for initramfs
3. fill()/flush() for initrd.

in the unlz4 does not handle case 3, as input len is passed as 0, and it
failed in first try.

Fix that add one extra if (fill) checking, and get out if EOF from the
fill().

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/qnx6: update debugging to current functions

Add DDEBUG in Makefile when CONFIG_QNX6FS_DEBUG is set.  All QNX6DEBUG
messages are replaced by pr_debug which means debugging will be emitted in
debug level only and no more in error and info levels.  debug uses now
pr_fmt and __func__

QNX6DEBUG definition has been removed.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Bankett <chaosman@ontika.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/qnx6: use pr_fmt and __func__ in logging

Remove "qnx6:" and "qnx6: " from each logging instruction.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Bankett <chaosman@ontika.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/qnx6: convert printk to pr_foo()

Use current logging functions.

Coalesce formats.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Bankett <chaosman@ontika.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/romfs/super.c: add blank line after declarations

Fix checkpatch warning:

  WARNING: Missing a blank line after declarations

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/romfs/super.c: use pr_fmt in logging

- Remove "Error" in format logging (already in pr_ level)

- Use modulename in pr_fmt instead of ROMFS: in each pr_ callsites.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/romfs/super.c: convert printk to pr_foo()

Use current logging functions. Coalesce formats.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/cramfs/inode.c: use linux/uaccess.h

Fixes checkpatch warning:

  WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/cramfs: code clean-up

Fixes some checkpatch errors/warnings:

  WARNING: Missing a blank line after declarations
  ERROR: spaces required around that '=' (ctx:VxV)
  ERROR: "foo * bar" should be "foo *bar"
  ERROR: space prohibited after that open parenthesis '('

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/cramfs: use pr_fmt

Use module name for "cramfs: " prefix.  (note that uncompress.c printk had
no prefix).

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/cramfs: convert printk to pr_foo()

Use current logging functions.  No level printk converted to pr_err

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tools/testing/selftests/ptrace/peeksiginfo.c: add PAGE_SIZE definition

On IBM powerpc where multiple page size value are supported, current
ppc64 and ppc64el distro don't define the PAGE_SIZE variable in
/usr/include as this is a dynamic value retrieved by the getpagesize()
or sysconf() defined in unistd.h.  The PAGE_SIZE variable sounds defined
when only one value is supported by the kernel.

As such, when the PAGE_SIZE definition doesn't exist system should
retrieve the dynamic value.

Signed-off-by: Thierry Fauck <thierry@linux.vnet.ibm.com>
Cc: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kfifo: use BUG_ON

Use BUG_ON(x) rather than if(x) BUG();

The semantic patch that fixes this problem is as follows:

// <smpl>
@@ identifier x; @@
-if (!x) BUG();
+BUG_ON(!x);
// </smpl>

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/omfs/inode.c: replace count*size kzalloc by kcalloc

kcalloc manages count*sizeof overflow.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/pstore/ram_core.c: replace count*size kmalloc by kmalloc_array

kmalloc_array manages count*sizeof overflow.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/parport/parport_ip32.c: use PTR_ERR_OR_ZERO

replace IS_ERR/PTR_ERR

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Wolfram Sang <wsa@the-dreams.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>