This adds "norecovery" mount option which disables temporal write
access to read-only mounts or snapshots during mount/recovery.
Without this option, write access will be even performed for those
types of mounts; the temporal write access is needed to mount root
file system read-only after an unclean shutdown.

This option will be helpful when user wants to prevent any write
access to the device.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Eric Sandeen <sandeen@redhat.com>

This adds a helper function, nilfs_valid_fs() which returns if nilfs
is in a valid state or not.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Although mount recovery of nilfs is integrated in load_nilfs()
procedure, the completion of recovery was isolated from the procedure
and performed at the end of the fill_super routine.

This was somewhat confusing since the recovery is needed for the nilfs
object, not for a super block instance.

To resolve the inconsistency, this will integrate the recovery
completion into load_nilfs().
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This inserts readahead in the recovery code.  The readahead request is
issued per segment while searching the latest super root block.

This will shorten mount time after unclean unmount.  A measurement
shows the recovery time was reduced by more than 60 percent:

 e.g. real  0m11.586s -> 0m3.918s  (x 2.96)
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This eliminates obsolete nilfs_get_sufile_get_segment_usage() and
nilfs_set_sufile_segment_usage() from sufile.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds nilfs_sufile_set_segment_usage() function in sufile to
replace direct access to the sufile metadata in log writer code.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds nilfs_sufile_mark_dirty() function in sufile to replace
nilfs_touch_segusage() function in log writer code.  This is a
preparation for the further cleanup which will move out low level
sufile operations in the log writer.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This implements cache operation in get block routines of palloc code:
nilfs_palloc_get_desc_block(), nilfs_palloc_get_bitmap_block(), and
nilfs_palloc_get_entry_block().

This will complete the palloc cache.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds the palloc cache to ifile.  The palloc cache is allocated on
the extended region of nilfs_mdt_info struct.  The struct
nilfs_ifile_info defines the extended on memory structure of ifile.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Data pages in gcdat metadata file (i.e. the secondary DAT for GC), are
cleared or even moved back to the normal DAT when a shot of garbage
collection was done.

Buffer heads held by the palloc cache of gcdat must be cleared before
these page cache manipulation.  This adds nilfs_palloc_clear_cache()
to ensure this.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds the palloc cache to DAT file.  The palloc cache is allocated
on the extended region of nilfs_mdt_info struct.  The struct
nilfs_dat_info defines the extended on memory structure of DAT.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds setup and cleanup routines of the persistent object
allocator cache.

According to ftrace analyses, accessing buffers of the DAT file
suffers indispensable overhead many times.  To mitigate the overhead,
This introduce cache framework for the persistent object allocator
(palloc) which the DAT file and ifile are using.

struct nilfs_palloc_cache represents the cache object per metadata
file using palloc.

The cache is initialized through nilfs_palloc_setup_cache() and
destroyed by nilfs_palloc_destroy_cache(); callers of the former
function will be added to individual allocators of DAT and ifile on
successive patches.

nilfs_palloc_destroy_cache() will be called from nilfs_mdt_destroy()
if the cache is attached to a metadata file.  A companion function
nilfs_palloc_clear_cache() is provided to allow releasing buffer head
references independently with the cleanup task.  This adjunctive
function will be used before invalidating pages of metadata file with
the cache.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This expands a trivial address calculation in the function into its
every callsite. This expansion improves readability of the callers.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This removes the obsolete nilfs_btnode_get() function and makes
nilfs_btree_get_block() directly call nilfs_btnode_submit_block().

This expansion will provide better opportunity for code optimization.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This removes the obsolete argument from nilfs_btnode_submit_block().
This will complete separating a create function of btree node.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This displaces nilfs_btnode_get() use to create new btree node block
with nilfs_btnode_create_block.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Adds a separate routine for creating a btree node block.  This is a
preparation to reduce the depth of function calls during submitting
btree node buffer.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This turns off readhead action of metadata file if nilfs_mdt_get_block
function was called with a create flag.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Previously, this function took an status code to return possible error
codes.  The ("nilfs2: add local variable to cache the number of clean
segments") patch removed the possibility to return errors.

So, this simplifies the function definition to make it directly return
the number of clean segments.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This makes it possible for sufile to get the number of clean segments
faster.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This unfolds the nilfs_sufile_block_get_header() function for
simplicity.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This will hide a function call of nilfs_mdt_clear() in
nilfs_mdt_destroy().

This ensures nilfs_mdt_destroy() to do cleanup jobs included in
nilfs_mdt_clear().
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Removes two inline functions: nilfs_mdt_read_inode_direct() and
nilfs_mdt_write_inode_direct().
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Will displace nilfs_mdt_read_inode_direct function with an individual
read method: nilfs_dat_read, nilfs_sufile_read, nilfs_cpfile_read.

This provides the opportunity to initialize local variables of each
metadata file after reading the inode.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This will displace nilfs_mdt_new() constructor with individual
metadata file constructors like nilfs_dat_new(), new_sufile_new(),
nilfs_cpfile_new(), and nilfs_ifile_new().

This makes it possible for each metadata file to have own
intialization code.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds an optional "object size" argument to nilfs_mdt_new_common()
function; the argument specifies the size of private object attached
to a newly allocated metadata file inode.

This will afford space to keep local variables for meta data files.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Previously, nilfs_bmap_add_blocks() and nilfs_bmap_sub_blocks() called
mark_inode_dirty() after they changed the number of data blocks.

This moves these calls outside bmap outermost functions like
nilfs_bmap_insert() or nilfs_bmap_truncate().

This will mitigate overhead for truncate or delete operation since
they repeatedly remove set of blocks.  Nearly 10 percent improvement
was observed for removal of a large file:

 # dd if=/dev/zero of=/test/aaa bs=1M count=512
 # time rm /test/aaa

  real  2.968s -> 2.705s

Further optimization may be possible by eliminating these
mark_inode_dirty() uses though I avoid mixing separate changes here.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Since metadata file routines mark the inode dirty after they
successfully changed bmap objects, nilfs_mdt_mark_dirty() calls in
nilfs_bmap_add_blocks() and nilfs_bmap_sub_blocks() are redundant.

This removes these overlapping calls from the bmap routines.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

lock_buffer() and unlock_buffer() uses in btree.c are eliminable
because btree functions gain buffer heads through nilfs_btnode_get(),
which never returns an on-the-fly buffer.

Although nilfs_clear_dirty_page() and nilfs_copy_back_pages() in
nilfs_commit_gcdat_inode() juggle btree node buffers of DAT, this is
safe because these operations are protected by a log writer lock or
the metadata file semaphore of DAT.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This lock is eliminable because inodes on the buffer can be updated
independently.  Although a log writer also fills in bmap data on the
on-disk inodes, this update is exclusively done by a log writer lock.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

match_bool function is not used anymore.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Since most of fs using nofoobar style option,
modified barrier=off option as nobarrier.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This is a trivial patch to expose struct nilfs_fs_btree_node.
The struct should be exposed outside of kernel, for it is disk format.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

The current btree lookup routines make a kernel oops when detected
inconsistency in btree blocks.  These routines should instead return a
proper error code because the inconsistency usually comes from
corruption of on-disk metadata.

This fixes the issue by converting BUG_ON calls to proper error
handlings.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  SUNRPC: Address buffer overrun in rpc_uaddr2sockaddr()
  NFSv4: Fix a cache validation bug which causes getcwd() to return ENOENT

As this struct is exposed to user space and the API was added for this
release it's a bit of a pain for the C++ world and we still have time to
fix it. Rename the fields before we end up with that pain in an actual
release.
Signed-off-by: Alan Cox <alan@linux.intel.com>
Reported-by: Olivier Goffart
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 86cf898e ("intel-iommu: Check for
'DMAR at zero' BIOS error earlier.") was supposed to work by pretending
not to detect an IOMMU if it was actually being reported by the BIOS at
physical address zero.

However, the intel_iommu_init() function is called unconditionally, as
are the corresponding functions for other IOMMU hardware.

So the patch only worked if you have RAM above the 4GiB boundary. It
caused swiotlb to be initialised when no IOMMU was detected during early
boot, and thus the later IOMMU init would refuse to run.

But if you have less RAM than that, swiotlb wouldn't get set up and the
IOMMU _would_ still end up being initialised, even though we never
claimed to detect it.

This patch also sets the dmar_disabled flag when the error is detected
during the initial detection phase -- so that the later call to
intel_iommu_init() will return without doing anything, regardless of
whether swiotlb is used or not.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
  [CPUFREQ] Fix stale cpufreq_cpu_governor pointer
  [CPUFREQ] Resolve time unit thinko in ondemand/conservative govs
  [CPUFREQ] speedstep-ich: fix error caused by 394122ab
  [CPUFREQ] Fix use after free on governor restore
  [CPUFREQ] acpi-cpufreq: blacklist Intel 0f68: Fix HT detection and put in notification message
  [CPUFREQ] powernow-k8: Fix test in get_transition_latency()
  [CPUFREQ] longhaul: select Longhaul version 2 for capable CPUs

Doing the strcmp return value as

	signed char __res = *cs - *ct;

is wrong for two reasons.  The subtraction can overflow because __res
doesn't use a type big enough.  Moreover the compared bytes should be
interpreted as unsigned char as specified by POSIX.

The same problem is fixed in strncmp.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>