A page can have multiple buffers and even if a page is not uptodate, some buffers
can be uptodate on pagesize != blocksize environment.
This aops checks that all buffers which correspond to a part of a file
that we want to read are uptodate. If so, we do not have to issue actual
read IO to HDD even if a page is not uptodate because the portion we
want to read are uptodate.
"block_is_partially_uptodate" function is already used by ext2/3/4.
With the following patch random read/write mixed workloads or random read after
random write workloads can be optimized and we can get performance improvement.
Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

For nfs exporting, ocfs2_get_dentry() returns the dentry for fh.
ocfs2_get_dentry() may read from disk when the inode is not in memory,
without any cross cluster lock. this leads to the file system loading a
stale inode.

This patch fixes above problem.

Solution is that in case of inode is not in memory, we get the cluster
lock(PR) of alloc inode where the inode in question is allocated from (this
causes node on which deletion is done sync the alloc inode) before reading
out the inode itsself. then we check the bitmap in the group (the inode in
question allcated from) to see if the bit is clear. if it's clear then it's
stale. if the bit is set, we then check generation as the existing code
does.

We have to read out the inode in question from disk first to know its alloc
slot and allot bit. And if its not stale we read it out using ocfs2_iget().
The second read should then be from cache.

And also we have to add a per superblock nfs_sync_lock to cover the lock for
alloc inode and that for inode in question. this is because ocfs2_get_dentry()
and ocfs2_delete_inode() lock on them in reverse order. nfs_sync_lock is locked
in EX mode in ocfs2_get_dentry() and in PR mode in ocfs2_delete_inode(). so
that mutliple ocfs2_delete_inode() can run concurrently in normal case.

[mfasheh@suse.com: build warning fixes and comment cleanups]
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

The debugfs file, mle_state, now prints the number of largest number of mles
in one hash link.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch attempts to fix a fine race between purging and migration.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch removes struct dlm_lock_name and adds the entries directly
to struct dlm_master_list_entry. Under the new scheme, both mles that
are backed by a lockres or not, will have the name populated in mle->mname.
This allows us to get rid of code that was figuring out the location of
the mle name.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch shows the number of lockres' and mles in the debugfs file, dlm_state.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch inlines dlm_set_lockres_owner() and dlm_change_lockres_owner().
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch replaces the lockres counts that tracked the number number of
locally and remotely mastered lockres' with a current and total count. The
total count is the number of lockres' that have been created since the dlm
domain was created.

The number of locally and remotely mastered counts can be computed using
the locking_state output.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

The lifetime of a mle is limited to the duration of the lockres mastery
process. While typically this lifetime is fairly short, we have noticed
the number of mles explode under certain circumstances. This patch tracks
the number of each different types of mles and should help us determine
how best to speed up the mastery process.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

The previous patch explicitly did not indent dlm_cleanup_master_list()
so as to make the patch readable. This patch properly indents the
function.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

With this patch, the mles are stored in a hash and not a simple list.
This should improve the mle lookup time when the number of outstanding
masteries is large.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch adds code to create and destroy the dlm->master_hash.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch refactors dlm_clean_master_list() so as to make it
easier to convert the mle list to a hash.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

For master mle, the name it stored in the attached lockres in struct qstr.
For block and migration mle, the name is stored inline in struct dlm_lock_name.
This patch attempts to make struct dlm_lock_name look like a struct qstr. While
we could use struct qstr, we don't because we want to avoid having to malloc
and free the lockname string as the mle's lifetime is fairly short.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch encapsulates adding and removing of the mle from the
dlm->master_list. This patch is part of the series of patches that
converts the mle list to a mle hash.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

In ocfs2, the block group search looks for the "emptiest" group
to allocate from. So if the allocator has many equally(or almost
equally) empty groups, new block group will tend to get spread
out amongst them.

So we add osb_inode_alloc_group in ocfs2_super to record the last
used inode allocation group.
For more details, please see
http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy.

I have done some basic test and the results are a ten times improvement on
some cold-cache stat workloads.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

Inode groups used to be allocated from local alloc file,
but since we want all inodes to be contiguous enough, we
will try to allocate them directly from global_bitmap.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

In ocfs2, the inode block search looks for the "emptiest" inode
group to allocate from. So if an inode alloc file has many equally
(or almost equally) empty groups, new inodes will tend to get
spread out amongst them, which in turn can put them all over the
disk. This is undesirable because directory operations on conceptually
"nearby" inodes force a large number of seeks.

So we add ip_last_used_group in core directory inodes which records
the last used allocation group. Another field named ip_last_used_slot
is also added in case inode stealing happens. When claiming new inode,
we passed in directory's inode so that the allocation can use this
information.
For more details, please see
http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

ocfs2_dx_dir_rebalance() is passed the block offset of a dx leaf which needs
rebalancing. Since we rebalance an entire cluster at a time however, this
function needs to calculate the beginning of that cluster, in blocks. The
calculation was wrong, which would result in a read of non-leaf blocks. Fix
the calculation by adding ocfs2_block_to_cluster_start() which is a more
straight-forward way of determining this.
Reported-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

ocfs2_empty_dir() is far more expensive than checking link count. Since both
need to be checked at the same time, we can improve performance by checking
link count first.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

Since the disk format is finalized, we can set this feature bit in the
supported mask.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <Joel.Becker@oracle.com>

This little bit of extra accounting speeds up ocfs2_empty_dir()
dramatically by allowing us to short-circuit the full directory scan.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

Since we've now got a directory format capable of handling a large number of
entries, we can increase the maximum link count supported. This only gets
increased if the directory indexing feature is turned on.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>

The only operation which doesn't get faster with directory indexing is
insert, which still has to walk the entire unindexed directory portion to
find a free block. This patch provides an improvement in directory insert
performance by maintaining a singly linked list of directory leaf blocks
which have space for additional dirents.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>

Allow us to store a small number of directory index records in the
ocfs2_dx_root_block. This saves us a disk read on small to medium sized
directories (less than about 250 entries). The inline root is automatically
turned into a root block with extents if the directory size increases beyond
it's capacity.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>

This patch makes use of Ocfs2's flexible btree code to add an additional
tree to directory inodes. The new tree stores an array of small,
fixed-length records in each leaf block. Each record stores a hash value,
and pointer to a block in the traditional (unindexed) directory tree where a
dirent with the given name hash resides. Lookup exclusively uses this tree
to find dirents, thus providing us with constant time name lookups.

Some of the hashing code was copied from ext3. Unfortunately, it has lots of
unfixed checkpatch errors. I left that as-is so that tracking changes would
be easier.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>

Many directory manipulation calls pass around a tuple of dirent, and it's
containing buffer_head. Dir indexing has a bit more state, but instead of
adding yet more arguments to functions, we introduce 'struct
ocfs2_dir_lookup_result'. In this patch, it simply holds the same tuple, but
future patches will add more state.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>

This patch removes the debugfs file local_alloc_stats as that information
is now included in the fs_state debugfs file.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch creates a per mount debugfs file, fs_state, which exposes
information like, cluster stack in use, states of the downconvert, recovery
and commit threads, number of journal txns, some allocation stats, list of
all slots, etc.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

Move the definition of struct recovery_map from journal.c to journal.h. This
is preparation for the next patch.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch creates a debugfs file, o2hb/livesnodes, which exposes the
aggregate list of heartbeating node across all heartbeat regions.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

* 'ext3-latency-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext3: Add replace-on-rename hueristics for data=writeback mode
  ext3: Add replace-on-truncate hueristics for data=writeback mode
  ext3: Use WRITE_SYNC for commits which are caused by fsync()
  block_write_full_page: Use synchronous writes for WBC_SYNC_ALL writebacks

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6: (32 commits)
  regulator: twl4030 VAUX3 supports 3.0V
  regulator: Support disabling of unused regulators by machines
  regulator: Don't increment use_count for boot_on regulators
  twl4030-regulator: expose VPLL2
  regulator: refcount fixes
  regulator: Don't warn if we failed to get a regulator
  regulator: Allow boot_on regulators to be disabled by clients
  regulator: Implement list_voltage for WM835x LDOs and DCDCs
  twl4030-regulator: list more VAUX4 voltages
  regulator: Don't warn on omitted voltage constraints
  regulator: Implement list_voltage() for WM8400 DCDCs and LDOs
  MMC: regulator utilities
  regulator: twl4030 voltage enumeration (v2)
  regulator: twl4030 regulators
  regulator: get_status() grows kerneldoc
  regulator: enumerate voltages (v2)
  regulator: Fix get_mode() for WM835x DCDCs
  regulator: Allow regulators to set the initial operating mode
  regulator: Suggest use of datasheet supply or pin names for consumers
  regulator: email - update email address and regulator webpage.
  ...

* git://git.infradead.org/iommu-2.6:
  intel-iommu: Fix address wrap on 32-bit kernel.
  intel-iommu: Enable DMAR on 32-bit kernel.
  intel-iommu: fix PCI device detach from virtual machine
  intel-iommu: VT-d page table to support snooping control bit
  iommu: Add domain_has_cap iommu_ops
  intel-iommu: Snooping control support

Fixed trivial conflicts in arch/x86/Kconfig and drivers/pci/intel-iommu.c

* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-fscache: (41 commits)
  NFS: Add mount options to enable local caching on NFS
  NFS: Display local caching state
  NFS: Store pages from an NFS inode into a local cache
  NFS: Read pages from FS-Cache into an NFS inode
  NFS: nfs_readpage_async() needs to be accessible as a fallback for local caching
  NFS: Add read context retention for FS-Cache to call back with
  NFS: FS-Cache page management
  NFS: Add some new I/O counters for FS-Cache doing things for NFS
  NFS: Invalidate FsCache page flags when cache removed
  NFS: Use local disk inode cache
  NFS: Define and create inode-level cache objects
  NFS: Define and create superblock-level objects
  NFS: Define and create server-level objects
  NFS: Register NFS for caching and retrieve the top-level index
  NFS: Permit local filesystem caching to be enabled for NFS
  NFS: Add FS-Cache option bit and debug bit
  NFS: Add comment banners to some NFS functions
  FS-Cache: Make kAFS use FS-Cache
  CacheFiles: A cache that backs onto a mounted filesystem
  CacheFiles: Export things for CacheFiles
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (36 commits)
  dm: set queue ordered mode
  dm: move wait queue declaration
  dm: merge pushback and deferred bio lists
  dm: allow uninterruptible wait for pending io
  dm: merge __flush_deferred_io into caller
  dm: move bio_io_error into __split_and_process_bio
  dm: rename __split_bio
  dm: remove unnecessary struct dm_wq_req
  dm: remove unnecessary work queue context field
  dm: remove unnecessary work queue type field
  dm: bio list add bio_list_add_head
  dm snapshot: persistent fix dtr cleanup
  dm snapshot: move status to exception store
  dm snapshot: move ctr parsing to exception store
  dm snapshot: use DMEMIT macro for status
  dm snapshot: remove dm_snap header
  dm snapshot: remove dm_snap header use
  dm exception store: move cow pointer
  dm exception store: move chunk_fields
  dm exception store: move dm_target pointer
  ...

* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  fs: Add exofs to Kernel build
  exofs: Documentation
  exofs: export_operations
  exofs: super_operations and file_system_type
  exofs: dir_inode and directory operations
  exofs: address_space_operations
  exofs: symlink_inode and fast_symlink_inode operations
  exofs: file and file_inode operations
  exofs: Kbuild, Headers and osd utils

* 'for-linus' of git://oss.sgi.com/xfs/xfs: (61 commits)
  Revert "xfs: increase the maximum number of supported ACL entries"
  xfs: cleanup uuid handling
  xfs: remove m_attroffset
  xfs: fix various typos
  xfs: pagecache usage optimization
  xfs: remove m_litino
  xfs: kill ino64 mount option
  xfs: kill mutex_t typedef
  xfs: increase the maximum number of supported ACL entries
  xfs: factor out code to find the longest free extent in the AG
  xfs: kill VN_BAD
  xfs: kill vn_atime_* helpers.
  xfs: cleanup xlog_bread
  xfs: cleanup xlog_recover_do_trans
  xfs: remove another leftover of the old inode log item format
  xfs: cleanup log unmount handling
  Fix xfs debug build breakage by pushing xfs_error.h after
  xfs: include header files for prototypes
  xfs: make symbols static
  xfs: move declaration to header file
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6: (23 commits)
  parisc: move dereference_function_descriptor to process.c
  parisc: Move kernel Elf_Fdesc define to <asm/elf.h>
  parisc: fix build when ARCH_HAS_KMAP
  parisc: fix "make tar-pkg"
  parisc: drivers: fix warnings
  parisc: select BUG always
  parisc: asm/pdc.h should include asm/page.h
  parisc: led: remove proc_dir_entry::owner
  parisc: fix macro expansion in atomic.h
  parisc: iosapic: fix build breakage
  parisc: oops_enter()/oops_exit() in die()
  parisc: document light weight syscall ABI
  parisc: blink all or loadavg LEDs on oops
  parisc: add ftrace (function and graph tracer) functionality
  parisc: simplify sys_clone()
  parisc: add LATENCYTOP_SUPPORT and CONFIG_STACKTRACE_SUPPORT
  parisc: allow to build with 16k default kernel page size
  parisc: expose 32/64-bit capabilities in cpuinfo
  parisc: use constants instead of numbers in assembly
  parisc: fix usage of 32bit PTE page table entries on 32bit kernels
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/kyle/rtc-parisc:
  powerpc/ps3: Add rtc-ps3
  powerpc: Hook up rtc-generic, and kill rtc-ppc
  m68k: Hook up rtc-generic
  parisc: rtc: Rename rtc-parisc to rtc-generic
  parisc: rtc: Add missing module alias
  parisc: rtc: platform_driver_probe() fixups
  parisc: rtc: get_rtc_time() returns unsigned int