nilfs_bmap_lookup and its variants are supposed to take a valid
pointer argument to return a block address, thus pointer checks in
nilfs_btree_lookup and nilfs_direct_lookup are needless.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This removes nilfs_bmap_union and finally unifies three structures and
the union in bmap/btree code into one.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This unifies two similar functions nilfs_btree_set_target_v and
nilfs_direct_set_target_v into one, nilfs_bmap_set_target_v.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This replaces all uses of nilfs_btree struct in implementation of
btree mapping with nilfs_bmap struct.

Name of local variable "btree" is kept not to bloat amount of change.
And, a part of local variables "bmap" is renamed to "btree" to uniform
naming rule.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This replaces all uses of nilfs_direct struct in implementation of
direct mapping with nilfs_bmap struct.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

The first argument of bops->bop_propagate operation takes a constant
qualifier, and causes compilation error when removed cast to pointer
of nilfs_btree structure type.  This fixes the issue to prepare for
succesive removal of nilfs_btree struct.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Will remove nilfs_bmap_key_to_dkey(), nilfs_bmap_dkey_to_key(),
nilfs_bmap_ptr_to_dptr(), and nilfs_bmap_dptr_to_ptr() for simplicity.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This inserts sanity checks soon after read btree node from disk.  This
allows early detection of broken btree nodes, and helps to narrow down
problems due to file system corruption.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

According to the report titled "problem with nilfs_cleanerd" from
Łukasz Wójcicki, nilfs_btree_lookup_dirty_buffers or
nilfs_btree_add_dirty_buffer got memory violation during garbage
collection.

This could happen if a level field of given btree node buffer is
incorrect, which is a crucial internal bug.

This inserts a sanity check to figure out the problem.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds is_remount argument to the parse_options() function that
obtains mount options from strings.

Previously, parse_options did not distinguish context whether it's
called for a new mount or remount, so the caller needed additional
verifications outside the function.

This allows parse_options to verify options and print messages
depending on the context.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This replaces seq_printf() with seq_puts() in nilfs_show_options for
mount options which have no argument.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Nilfs has "discard" mount option which issues discard/TRIM commands to
underlying block device, but it lacks a complementary option and has
no way to disable the feature through remount.

This adds "nodiscard" option to resolve this imbalance.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Nilfs enables write barriers by default and has "nobarrier" mount
option to disable this feature.  But it lacks the complementary option
and has no way to re-enable the feature on remount.

This adds "barrier" option to resolve this imbalance.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Super blocks of nilfs are periodically overwritten in order to record
the recent log position.  This shortens recovery time after unclean
unmount, but the current implementation performs the update even for a
few blocks of change.  If the filesystem gets small changes slowly and
continually, super blocks may be updated excessively.

This moderates the issue by skipping update of log cursor if it does
not cross a segment boundary.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Although nilfs redundantly uses two super blocks and each may point to
different position on log, the current version of nilfs does not try
fallback to the spare super block when it doesn't find any valid log
at the position that the primary super block points to.

This has been a cause of mount failures due to write order reversals
on barrier less block devices.

This inserts fallback code in error path of nilfs_search_super_root
routine to resolve the mount failure problem.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

nilfs_search_super_root can return -ENOMEM, but this error code is not
described in its kernel-doc comment.  This fixes the discrepancy.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This separates a setup routine of log cursor from init_nilfs().  The
routine, nilfs_store_log_cursor, reads the last position of the log
containing a super root, and initializes relevant state on the nilfs
object.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This will sync super blocks in turns instead of syncing duplicate
super blocks at the time.  This will help searching valid super root
when super block is written into disk before log is written, which is
happen when barrier-less block devices are unmounted uncleanly.  In
the situation, old super block likely points to valid log.

This patch introduces ns_sbwcount member to the nilfs object and adds
nilfs_sb_will_flip() function; ns_sbwcount counts how many times super
blocks write back to the disk.  And, nilfs_sb_will_flip() decides
whether flipping required or not based on the count of ns_sbwcount to
sync super blocks asymmetrically.

The following functions are also changed:

 - nilfs_prepare_super(): flips super blocks according to the
   argument.  The argument is calculated by nilfs_sb_will_flip()
   function.

 - nilfs_cleanup_super(): sets "clean" flag to both super blocks if
   they point to the same checkpoint.

To update both of super block information, caller of
nilfs_commit_super must set the information on both super blocks.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This function checks validity of super block pointers.
If first super block is invalid, it will swap the super blocks.
The function should be called before any super block information updates.
Caller must obtain nilfs->ns_sem.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This moves out section that updates information of the recent log
position stored in super blocks from nilfs_commit_super to a new
routine named nilfs_set_log_cursor.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This function marks error state and write it on super blocks.  This is
a preparation for making super block writeback alternately.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This function write out filesystem state to super blocks in order to
share the same cleanup work.  This is a preparation for making super
block writeback alternately.

Cc: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Mount time field in super block is wrongly updated when nilfs remounts
the partition from read-write to read-only.  This fixes the issue.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This counter is unused.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This removes macros to test segment summary flags and redefines a few
relevant macros with inline functions.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This will get rid of nilfs_segsum_info use from recovery functions for
simplicity.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

load_segment_summary function has two distinct roles: getting summary
header of a log, and verifying consistencies of the log.

This divide it into two corresponding functions, nilfs_read_log_header
and nilfs_validate_log to clarify the meaning.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

The function name of nilfs_recover_logical_segments makes no sense.
This changes the name into nilfs_salvage_orphan_logs to clarify the
role of the function.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Most functions in recovery code take an argument of a super block
instance or a nilfs_sb_info struct for convenience sake.

This replaces them aggressively with a nilfs object by applying
__bread and __breadahead against routines using sb_bread and
sb_breadahead.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This stores blocksize in nilfs objects for the successive refactoring
of recovery logic.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: synaptics - relax capability ID checks on newer hardware
  Input: twl40300-keypad - fix handling of "all ground" rows
  Input: gamecon - reference correct pad in gc_psx_command()
  Input: gamecon - reference correct input device in NES mode
  Input: w90p910_keypad - change platfrom driver name to 'nuc900-kpi'
  Input: i8042 - add Gigabyte Spring Peak to dmi_noloop_table
  Input: qt2160 - rename kconfig symbol name

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms: add quirk to make HP DV5000 laptop resume
  drm/radeon/kms: fix RADEON_INFO_CRTC_FROM_ID info ioctl
  Fix ttm_page_alloc.c build breakage
  drm/radeon/kms: fix legacy LVDS dpms sequence
  drm/radeon/kms: drop taking lock around crtc lookup.

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: talitos - fix bug in sg_copy_end_to_buffer

Merge branch 'x86/auditsyscall' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland

* 'x86/auditsyscall' of git://git.kernel.org/pub/scm/linux/kernel/git/frob/linux-2.6-roland:
  x86: auditsyscall: fix fastpath return value after reschedule

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  sysrq,kdb: Use __handle_sysrq() for kdb's sysrq function
  debug_core,kdb: fix kgdb_connected bit set in the wrong place
  Fix merge regression from external kdb to upstream kdb
  repair gdbstub to match the gdbserial protocol specification
  kdb: break out of kdb_ll() when command is terminated

Fix the security problem in the CIFS filesystem DNS lookup code in which a
malicious redirect could be installed by a random user by simply adding a
result record into one of their keyrings with add_key() and then invoking a
CIFS CFS lookup [CVE-2010-2524].

This is done by creating an internal keyring specifically for the caching of
DNS lookups.  To enforce the use of this keyring, the module init routine
creates a set of override credentials with the keyring installed as the thread
keyring and instructs request_key() to only install lookup result keys in that
keyring.

The override is then applied around the call to request_key().

This has some additional benefits when a kernel service uses this module to
request a key:

 (1) The result keys are owned by root, not the user that caused the lookup.

 (2) The result keys don't pop up in the user's keyrings.

 (3) The result keys don't come out of the quota of the user that caused the
     lookup.

The keyring can be viewed as root by doing cat /proc/keys:

2a0ca6c3 I-----     1 perm 1f030000     0     0 keyring   .dns_resolver: 1/4

It can then be listed with 'keyctl list' by root.

	# keyctl list 0x2a0ca6c3
	1 key in keyring:
	726766307: --alswrv     0     0 dns_resolver: foo.bar.com
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Steve French <smfrench@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=29062Reported-by: Andres Cimmarusti <acimmarusti@gmail.com>
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Older firmwares fixed the middle byte of the Synaptics capabilities
query to 0x47, but starting with firmware 7.5 the middle byte
represents submodel ID, sometimes also called "dash number".
Reported-and-tested-by: Miroslav Šulc <fordfrog@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

In the CONFIG_AUDITSYSCALL fast-path for x86 64-bit system calls,
we can pass a bad return value and/or error indication for the
system call to audit_syscall_exit().  This happens when
TIF_NEED_RESCHED was set as the system call returned, so we went
out to schedule() and came back to the exit-audit fast-path.  The
fix is to reload the user return value register from the pt_regs
before using it for audit_syscall_exit().

Both the 32-bit kernel's fast path and the 64-bit kernel's 32-bit
system call fast paths work slightly differently, so that they
always leave the fast path entirely to reschedule and don't return
there, so they don't have the analogous bugs.
Reported-by: Alexander Viro <aviro@redhat.com>
Signed-off-by: Roland McGrath <roland@redhat.com>