Commit graph

295 commits

Author SHA1 Message Date
Tao Ma f19d5870cb ext4: add normal write support for inline data
For a normal write case (not journalled write, not delayed
allocation), we write to the inline if the file is small and convert
it to an extent based file when the write is larger than the max
inline size.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-12-10 14:05:51 -05:00
Tao Ma 67cf5b09a4 ext4: add the basic function for inline data support
Implement inline data with xattr.

Now we use "system.data" to store xattr, and the xattr will
be extended if the i_size is increased while we don't release
the space during truncate.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-12-10 14:04:46 -05:00
Theodore Ts'o 4a092d7379 ext4: rationalize ext4_extents.h inclusion
Previously, ext4_extents.h was being included at the end of ext4.h,
which was bad for a number of reasons: (a) it was not being included
in the expected place, and (b) it caused the header to be included
multiple times.  There were #ifdef's to prevent this from causing any
problems, but it still was unnecessary.

By moving the function declarations that were in ext4_extents.h to
ext4.h, which is standard practice for where the function declarations
for the rest of ext4.h can be found, we can remove ext4_extents.h from
being included in ext4.h at all, and then we can only include
ext4_extents.h where it is needed in ext4's source files.

It should be possible to move a few more things into ext4.h, and
further reduce the number of source files that need to #include
ext4_extents.h, but that's a cleanup for another day.

Reported-by: Sachin Kamat <sachin.kamat@linaro.org>
Reported-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-28 13:03:30 -05:00
Zheng Liu 7d1b1fbc95 ext4: reimplement ext4_find_delay_alloc_range on extent status tree
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 21:57:35 -05:00
Zheng Liu c0677e6d0f ext4: add data structures for the extent status tree
This patch adds two structures that supports extent status tree, extent_status
and ext4_es_tree.  Currently extent_status is used to track a delay extent for
an inode, which record the start block and the length of the delay extent.
ext4_es_tree is used to store all extent_status for an inode in memory.

Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-11-08 15:18:54 -05:00
Tao Ma 79f1ba4956 ext4: Checksum the block bitmap properly with bigalloc enabled
In mke2fs, we only checksum the whole bitmap block and it is right.
While in the kernel, we use EXT4_BLOCKS_PER_GROUP to indicate the
size of the checksumed bitmap which is wrong when we enable bigalloc.
The right size should be EXT4_CLUSTERS_PER_GROUP and this patch fixes
it.

Also as every caller of ext4_block_bitmap_csum_set and
ext4_block_bitmap_csum_verify pass in EXT4_BLOCKS_PER_GROUP(sb)/8,
we'd better removes this parameter and sets it in the function itself.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Cc: stable@vger.kernel.org
2012-10-22 00:34:32 -04:00
Theodore Ts'o 06db49e68a ext4: fix metadata checksum calculation for the superblock
The function ext4_handle_dirty_super() was calculating the superblock
on the wrong block data.  As a result, when the superblock is modified
while it is mounted (most commonly, when inodes are added or removed
from the orphan list), the superblock checksum would be wrong.  We
didn't notice because the superblock *was* being correctly calculated
in ext4_commit_super(), and this would get called when the file system
was unmounted.  So the problem only became obvious if the system
crashed while the file system was mounted.

Fix this by removing the poorly designed function signature for
ext4_superblock_csum_set(); if it only took a single argument, the
pointer to a struct superblock, the ambiguity which caused this
mistake would have been impossible.

Reported-by: George Spelvin <linux@horizon.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2012-10-10 01:06:58 -04:00
Dmitry Monakhov c278531d39 ext4: fix ext4_flush_completed_IO wait semantics
BUG #1) All places where we call ext4_flush_completed_IO are broken
    because buffered io and DIO/AIO goes through three stages
    1) submitted io,
    2) completed io (in i_completed_io_list) conversion pended
    3) finished  io (conversion done)
    And by calling ext4_flush_completed_IO we will flush only
    requests which were in (2) stage, which is wrong because:
     1) punch_hole and truncate _must_ wait for all outstanding unwritten io
      regardless to it's state.
     2) fsync and nolock_dio_read should also wait because there is
        a time window between end_page_writeback() and ext4_add_complete_io()
        As result integrity fsync is broken in case of buffered write
        to fallocated region:
        fsync                                      blkdev_completion
	 ->filemap_write_and_wait_range
                                                   ->ext4_end_bio
                                                     ->end_page_writeback
          <-- filemap_write_and_wait_range return
	 ->ext4_flush_completed_IO
   	 sees empty i_completed_io_list but pended
   	 conversion still exist
                                                     ->ext4_add_complete_io

BUG #2) Race window becomes wider due to the 'ext4: completed_io
locking cleanup V4' patch series

This patch make following changes:
1) ext4_flush_completed_io() now first try to flush completed io and when
   wait for any outstanding unwritten io via ext4_unwritten_wait()
2) Rename function to more appropriate name.
3) Assert that all callers of ext4_flush_unwritten_io should hold i_mutex to
   prevent endless wait

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
2012-10-05 11:31:55 -04:00
Dmitry Monakhov 17335dcc47 ext4: serialize dio nonlocked reads with defrag workers
Inode's block defrag and ext4_change_inode_journal_flag() may
affect nonlocked DIO reads result, so proper synchronization
required.

- Add missed inode_dio_wait() calls where appropriate
- Check inode state under extra i_dio_count reference.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 00:41:21 -04:00
Dmitry Monakhov 28a535f9a0 ext4: completed_io locking cleanup
Current unwritten extent conversion state-machine is very fuzzy.
- For unknown reason it performs conversion under i_mutex. What for?
  My diagnosis:
  We already protect extent tree with i_data_sem, truncate and punch_hole
  should wait for DIO, so the only data we have to protect is end_io->flags
  modification, but only flush_completed_IO and end_io_work modified this
  flags and we can serialize them via i_completed_io_lock.

  Currently all these games with mutex_trylock result in the following deadlock
   truncate:                          kworker:
    ext4_setattr                       ext4_end_io_work
    mutex_lock(i_mutex)
    inode_dio_wait(inode)  ->BLOCK
                             DEADLOCK<- mutex_trylock()
                                        inode_dio_done()
  #TEST_CASE1_BEGIN
  MNT=/mnt_scrach
  unlink $MNT/file
  fallocate -l $((1024*1024*1024)) $MNT/file
  aio-stress -I 100000 -O -s 100m -n -t 1 -c 10 -o 2 -o 3 $MNT/file
  sleep 2
  truncate -s 0 $MNT/file
  #TEST_CASE1_END

Or use 286's xfstests https://github.com/dmonakhov/xfstests/blob/devel/286

This patch makes state machine simple and clean:

(1) xxx_end_io schedule final extent conversion simply by calling
    ext4_add_complete_io(), which append it to ei->i_completed_io_list
    NOTE1: because of (2A) work should be queued only if
    ->i_completed_io_list was empty, otherwise the work is scheduled already.

(2) ext4_flush_completed_IO is responsible for handling all pending
    end_io from ei->i_completed_io_list
    Flushing sequence consists of following stages:
    A) LOCKED: Atomically drain completed_io_list to local_list
    B) Perform extents conversion
    C) LOCKED: move converted io's to to_free list for final deletion
       	     This logic depends on context which we was called from.
    D) Final end_io context destruction
    NOTE1: i_mutex is no longer required because end_io->flags modification
    is protected by ei->ext4_complete_io_lock

Full list of changes:
- Move all completion end_io related routines to page-io.c in order to improve
  logic locality
- Move open coded logic from various xx_end_xx routines to ext4_add_complete_io()
- remove EXT4_IO_END_FSYNC
- Improve SMP scalability by removing useless i_mutex which does not
  protect io->flags anymore.
- Reduce lock contention on i_completed_io_lock by optimizing list walk.
- Rename ext4_end_io_nolock to end4_end_io and make it static
- Check flush completion status to ext4_ext_punch_hole(). Because it is
  not good idea to punch blocks from corrupted inode.

Changes since V3 (in request to Jan's comments):
  Fall back to active flush_completed_IO() approach in order to prevent
  performance issues with nolocked DIO reads.
Changes since V2:
  Fix use-after-free caused by race truncate vs end_io_work

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-29 00:14:55 -04:00
Dmitry Monakhov e27f41e1b7 ext4: give i_aiodio_unwritten a more appropriate name
AIO/DIO prefix is wrong because it account unwritten extents which
also may be scheduled from buffered write endio

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-28 23:24:52 -04:00
Dmitry Monakhov f45ee3a1ea ext4: ext4_inode_info diet
Generic inode has unused i_private pointer which may be used as cur_aio_dio
storage.

TODO: If cur_aio_dio will be passed as an argument to get_block_t this allow
      to have concurent AIO_DIO requests.

Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-28 23:21:09 -04:00
Theodore Ts'o 28623c2f5b ext4: grow the s_group_info array as needed
Previously we allocated the s_group_info array with enough space for
any future possible growth of the file system via online resize.  This
is unfortunate because it wastes memory, and it doesn't work for the
meta_bg scheme, since there is no limit based on the number of
reserved gdt blocks.  So add the code to grow the s_group_info array
as needed.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-05 01:31:50 -04:00
Theodore Ts'o 117fff10d7 ext4: grow the s_flex_groups array as needed when resizing
Previously, we allocated the s_flex_groups array to the maximum size
that the file system could be resized.  There was two problems with
this approach.  First, it wasted memory in the common case where the
file system was not resized.  Secondly, once we start allowing online
resizing using the meta_bg scheme, there is no maximum size that the
file system can be resized.  So instead, we need to grow the
s_flex_groups at inline resize time.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-09-05 01:29:50 -04:00
Zheng Liu 67a5da564f ext4: make the zero-out chunk size tunable
Currently in ext4 the length of zero-out chunk is set to 7 file system
blocks.  But if an inode has uninitailized extents from using
fallocate to preallocate space, and the workload issues many random
writes, this can cause a fragmented extent tree that will
unnecessarily grow the extent tree.

So create a new sysfs tunable, extent_max_zeroout_kb, which controls
the maximum size where blocks will be zeroed out instead of creating a
new uninitialized extent.  The default of this has been sent to 32kb.

CC: Zach Brown <zab@zabbo.net>
CC: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-08-17 09:54:17 -04:00
Theodore Ts'o df981d03ee ext4: add max_dir_size_kb mount option
Very large directories can cause significant performance problems, or
perhaps even invoke the OOM killer, if the process is running in a
highly constrained memory environment (whether it is VM's with a small
amount of memory or in a small memory cgroup).

So it is useful, in cloud server/data center environments, to be able
to set a filesystem-wide cap on the maximum size of a directory, to
ensure that directories never get larger than a sane size.  We do this
via a new mount option, max_dir_size_kb.  If there is an attempt to
grow the directory larger than max_dir_size_kb, the system call will
return ENOSPC instead.

Google-Bug-Id: 6863013

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-08-17 09:48:17 -04:00
Jan Kara 044ce47fec ext4: convert last user of ext4_mark_super_dirty() to ext4_handle_dirty_super()
The last user of ext4_mark_super_dirty() in ext4_file_open() is so
rare it can well be modifying the superblock properly by journalling
the change.  Change it and get rid of ext4_mark_super_dirty() as it's
not needed anymore.

Artem: small amendments.
Artem: tested using xfstests for both journalled and non-journalled ext4.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Tested-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-07-22 20:31:31 -04:00
Theodore Ts'o 3108b54bce ext4: remove dynamic array size in ext4_chksum()
The ext4_checksum() inline function was using a dynamic array size,
which is not legal C.  (It is a gcc extension).

Remove it.

Cc: "Darrick J. Wong" <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-07-22 20:25:31 -04:00
Aditya Kali 7c319d3285 ext4: make quota as first class supported feature
This patch adds support for quotas as a first class feature in ext4;
which is to say, the quota files are stored in hidden inodes as file
system metadata, instead of as separate files visible in the file system
directory hierarchy.

It is based on the proposal at:                                                                                                           
https://ext4.wiki.kernel.org/index.php/Design_For_1st_Class_Quota_in_Ext4

This patch introduces a new feature - EXT4_FEATURE_RO_COMPAT_QUOTA
which, when turned on, enables quota accounting at mount time
iteself. Also, the quota inodes are stored in two additional superblock
fields.  Some changes introduced by this patch that should be pointed
out are:

1) Two new ext4-superblock fields - s_usr_quota_inum and
   s_grp_quota_inum for storing the quota inodes in use.
2) Default quota inodes are: inode#3 for tracking userquota and inode#4
   for tracking group quota. The superblock fields can be set to use
   other inodes as well.
3) If the QUOTA feature and corresponding quota inodes are set in
   superblock, the quota usage tracking is turned on at mount time. On
   'quotaon' ioctl, the quota limits enforcement is turned
   on. 'quotaoff' ioctl turns off only the limits enforcement in this
   case.
4) When QUOTA feature is in use, the quota mount options 'quota',
   'usrquota', 'grpquota' are ignored by the kernel.
5) mke2fs or tune2fs can be used to set the QUOTA feature and initialize
   quota inodes. The default reserved inodes will not be visible to user
   as regular files.
6) The quota-tools will need to be modified to support hidden quota
   files on ext4. E2fsprogs will also include support for creating and
   fixing quota files.
7) Support is only for the new V2 quota file format.

Tested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johann Lombardi <johann@whamcloud.com>
Signed-off-by: Aditya Kali <adityakali@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-07-22 20:21:31 -04:00
Zheng Liu 729f52c6be ext4: add a new nolock flag in ext4_map_blocks
EXT4_GET_BLOCKS_NO_LOCK flag is added to indicate that we don't need
to acquire i_data_sem lock in ext4_map_blocks.  Meanwhile, it changes
ext4_get_block() to not start a new journal because when we do a
overwrite dio, there is no any metadata that needs to be modified.

We define a new function called ext4_get_block_write_nolock, which is
used in dio overwrite nolock.  In this function, it doesn't try to
acquire i_data_sem lock and doesn't start a new journal as it does a
lookup.

CC: Tao Ma <tm@tao.ma>
CC: Eric Sandeen <sandeen@redhat.com>
CC: Robin Dong <hao.bigrat@gmail.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-07-09 16:29:29 -04:00
Theodore Ts'o 952fc18ef9 ext4: fix overhead calculation used by ext4_statfs()
Commit f975d6bcc7 introduced bug which caused ext4_statfs() to
miscalculate the number of file system overhead blocks.  This causes
the f_blocks field in the statfs structure to be larger than it should
be.  This would in turn cause the "df" output to show the number of
data blocks in the file system and the number of data blocks used to
be larger than they should be.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2012-07-09 16:27:05 -04:00
Theodore Ts'o f6fb99cadc ext4: pass a char * to ext4_count_free() instead of a buffer_head ptr
Make it possible for ext4_count_free to operate on buffers and not
just data in buffer_heads.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
2012-06-30 19:14:57 -04:00
Linus Torvalds 4edebed866 Ext4 updates for 3.5
The major new feature added in this update is Darrick J. Wong's
 metadata checksum feature, which adds crc32 checksums to ext4's
 metadata fields.  There is also the usual set of cleanups and bug
 fixes.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull Ext4 updates from Theodore Ts'o:
 "The major new feature added in this update is Darrick J Wong's
  metadata checksum feature, which adds crc32 checksums to ext4's
  metadata fields.

  There is also the usual set of cleanups and bug fixes."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits)
  ext4: hole-punch use truncate_pagecache_range
  jbd2: use kmem_cache_zalloc wrapper instead of flag
  ext4: remove mb_groups before tearing down the buddy_cache
  ext4: add ext4_mb_unload_buddy in the error path
  ext4: don't trash state flags in EXT4_IOC_SETFLAGS
  ext4: let getattr report the right blocks in delalloc+bigalloc
  ext4: add missing save_error_info() to ext4_error()
  ext4: add debugging trigger for ext4_error()
  ext4: protect group inode free counting with group lock
  ext4: use consistent ssize_t type in ext4_file_write()
  ext4: fix format flag in ext4_ext_binsearch_idx()
  ext4: cleanup in ext4_discard_allocated_blocks()
  ext4: return ENOMEM when mounts fail due to lack of memory
  ext4: remove redundundant "(char *) bh->b_data" casts
  ext4: disallow hard-linked directory in ext4_lookup
  ext4: fix potential integer overflow in alloc_flex_gd()
  ext4: remove needs_recovery in ext4_mb_init()
  ext4: force ro mount if ext4_setup_super() fails
  ext4: fix potential NULL dereference in ext4_free_inodes_counts()
  ext4/jbd2: add metadata checksumming to the list of supported features
  ...
2012-06-01 10:12:15 -07:00
Theodore Ts'o 2c0544b235 ext4: add debugging trigger for ext4_error()
Make it easy to test whether or not the error handling subsystem in
ext4 is working correctly.  This allows us to simulate an ext4_error()
by echoing a string to /sys/fs/ext4/<dev>/trigger_fs_error.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: ksumrall@google.com
2012-05-30 22:56:46 -04:00
Akira Fujita 9d99012ff2 ext4: remove needs_recovery in ext4_mb_init()
needs_recovery in ext4_mb_init() is not used, remove it.

Signed-off-by: Akira Fujita <a-fujita@rs.jp.ne.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-05-28 14:19:25 -04:00
Darrick J. Wong e93376c20b ext4/jbd2: add metadata checksumming to the list of supported features
Activate the metadata checksumming feature by adding it to ext4 and
jbd2's lists of supported features.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-05-27 08:12:42 -04:00
Linus Torvalds 644473e9c6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace enhancements from Eric Biederman:
 "This is a course correction for the user namespace, so that we can
  reach an inexpensive, maintainable, and reasonably complete
  implementation.

  Highlights:
   - Config guards make it impossible to enable the user namespace and
     code that has not been converted to be user namespace safe.

   - Use of the new kuid_t type ensures the if you somehow get past the
     config guards the kernel will encounter type errors if you enable
     user namespaces and attempt to compile in code whose permission
     checks have not been updated to be user namespace safe.

   - All uids from child user namespaces are mapped into the initial
     user namespace before they are processed.  Removing the need to add
     an additional check to see if the user namespace of the compared
     uids remains the same.

   - With the user namespaces compiled out the performance is as good or
     better than it is today.

   - For most operations absolutely nothing changes performance or
     operationally with the user namespace enabled.

   - The worst case performance I could come up with was timing 1
     billion cache cold stat operations with the user namespace code
     enabled.  This went from 156s to 164s on my laptop (or 156ns to
     164ns per stat operation).

   - (uid_t)-1 and (gid_t)-1 are reserved as an internal error value.
     Most uid/gid setting system calls treat these value specially
     anyway so attempting to use -1 as a uid would likely cause
     entertaining failures in userspace.

   - If setuid is called with a uid that can not be mapped setuid fails.
     I have looked at sendmail, login, ssh and every other program I
     could think of that would call setuid and they all check for and
     handle the case where setuid fails.

   - If stat or a similar system call is called from a context in which
     we can not map a uid we lie and return overflowuid.  The LFS
     experience suggests not lying and returning an error code might be
     better, but the historical precedent with uids is different and I
     can not think of anything that would break by lying about a uid we
     can't map.

   - Capabilities are localized to the current user namespace making it
     safe to give the initial user in a user namespace all capabilities.

  My git tree covers all of the modifications needed to convert the core
  kernel and enough changes to make a system bootable to runlevel 1."

Fix up trivial conflicts due to nearby independent changes in fs/stat.c

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
  userns:  Silence silly gcc warning.
  cred: use correct cred accessor with regards to rcu read lock
  userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq
  userns: Convert cgroup permission checks to use uid_eq
  userns: Convert tmpfs to use kuid and kgid where appropriate
  userns: Convert sysfs to use kgid/kuid where appropriate
  userns: Convert sysctl permission checks to use kuid and kgids.
  userns: Convert proc to use kuid/kgid where appropriate
  userns: Convert ext4 to user kuid/kgid where appropriate
  userns: Convert ext3 to use kuid/kgid where appropriate
  userns: Convert ext2 to use kuid/kgid where appropriate.
  userns: Convert devpts to use kuid/kgid where appropriate
  userns: Convert binary formats to use kuid/kgid where appropriate
  userns: Add negative depends on entries to avoid building code that is userns unsafe
  userns: signal remove unnecessary map_cred_ns
  userns: Teach inode_capable to understand inodes whose uids map to other namespaces.
  userns: Fail exec for suid and sgid binaries with ids outside our user namespace.
  userns: Convert stat to return values mapped from kuids and kgids
  userns: Convert user specfied uids and gids in chown into kuids and kgid
  userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs
  ...
2012-05-23 17:42:39 -07:00
Eric W. Biederman 08cefc7ab8 userns: Convert ext4 to user kuid/kgid where appropriate
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-05-15 14:59:27 -07:00
Darrick J. Wong 5c359a47e7 ext4: add checksums to the MMP block
Compute and verify a checksum for the MMP block.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:47:10 -04:00
Darrick J. Wong feb0ab32a5 ext4: make block group checksums use metadata_csum algorithm
metadata_csum supersedes uninit_bg.  Convert the ROCOMPAT uninit_bg
flag check to a helper function that covers both, and make the
checksum calculation algorithm use either crc16 or the metadata_csum
chosen algorithm depending on which flag is set.  Print a warning if
we try to mount a filesystem with both feature flags set.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:45:10 -04:00
Darrick J. Wong b0336e8d21 ext4: calculate and verify checksums of directory leaf blocks
Calculate and verify the checksums for directory leaf blocks
(i.e. blocks that only contain actual directory entries).  The
checksum lives in what looks to be an unused directory entry with a 0
name_len at the end of the block.  This scheme is not used for
internal htree nodes because the mechanism in place there only costs
one dx_entry, whereas the "empty" directory entry would cost two
dx_entries.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:41:10 -04:00
Darrick J. Wong fa77dcfafe ext4: calculate and verify block bitmap checksum
Compute and verify the checksum of the block bitmap; this checksum is
stored in the block group descriptor.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:35:10 -04:00
Darrick J. Wong 41a246d1ff ext4: calculate and verify checksums for inode bitmaps
Compute and verify the checksum of the inode bitmap; the checkum is
stored in the block group descriptor.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:33:10 -04:00
Darrick J. Wong 814525f4df ext4: calculate and verify inode checksums
This patch introduces to ext4 the ability to calculate and verify
inode checksums.  This requires the use of a new ro compatibility flag
and some accompanying e2fsprogs patches to provide the relevant
features in tune2fs and e2fsck.  The inode generation changes have
been integrated into this patch.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:31:10 -04:00
Darrick J. Wong a9c4731780 ext4: calculate and verify superblock checksum
Calculate and verify the superblock checksum.  Since the UUID and
block group number are embedded in each copy of the superblock, we
need only checksum the entire block.  Refactor some of the code to
eliminate open-coding of the checksum update call.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:29:10 -04:00
Darrick J. Wong 0441984a33 ext4: load the crc32c driver if necessary
Obtain a reference to the cryptoapi and crc32c if we mount a
filesystem with metadata checksumming enabled.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:27:10 -04:00
Darrick J. Wong e615391896 ext4: change on-disk layout to support extended metadata checksumming
Define flags and change structure definitions to allow checksumming of
ext4 metadata.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-04-29 18:23:10 -04:00
Theodore Ts'o 9cd70b347e ext4: address scalability issue by removing extent cache statistics
Andi Kleen and Tim Chen have reported that under certain circumstances
the extent cache statistics are causing scalability problems due to
cache line bounces.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2012-04-16 12:16:20 -04:00
Linus Torvalds 71db34fc43 Merge branch 'for-3.4' of git://linux-nfs.org/~bfields/linux
Pull nfsd changes from Bruce Fields:

Highlights:
 - Benny Halevy and Tigran Mkrtchyan implemented some more 4.1 features,
   moving us closer to a complete 4.1 implementation.
 - Bernd Schubert fixed a long-standing problem with readdir cookies on
   ext2/3/4.
 - Jeff Layton performed a long-overdue overhaul of the server reboot
   recovery code which will allow us to deprecate the current code (a
   rather unusual user of the vfs), and give us some needed flexibility
   for further improvements.
 - Like the client, we now support numeric uid's and gid's in the
   auth_sys case, allowing easier upgrades from NFSv2/v3 to v4.x.

Plus miscellaneous bugfixes and cleanup.

Thanks to everyone!

There are also some delegation fixes waiting on vfs review that I
suppose will have to wait for 3.5.  With that done I think we'll finally
turn off the "EXPERIMENTAL" dependency for v4 (though that's mostly
symbolic as it's been on by default in distro's for a while).

And the list of 4.1 todo's should be achievable for 3.5 as well:

   http://wiki.linux-nfs.org/wiki/index.php/Server_4.0_and_4.1_issues

though we may still want a bit more experience with it before turning it
on by default.

* 'for-3.4' of git://linux-nfs.org/~bfields/linux: (55 commits)
  nfsd: only register cld pipe notifier when CONFIG_NFSD_V4 is enabled
  nfsd4: use auth_unix unconditionally on backchannel
  nfsd: fix NULL pointer dereference in cld_pipe_downcall
  nfsd4: memory corruption in numeric_name_to_id()
  sunrpc: skip portmap calls on sessions backchannel
  nfsd4: allow numeric idmapping
  nfsd: don't allow legacy client tracker init for anything but init_net
  nfsd: add notifier to handle mount/unmount of rpc_pipefs sb
  nfsd: add the infrastructure to handle the cld upcall
  nfsd: add a header describing upcall to nfsdcld
  nfsd: add a per-net-namespace struct for nfsd
  sunrpc: create nfsd dir in rpc_pipefs
  nfsd: add nfsd4_client_tracking_ops struct and a way to set it
  nfsd: convert nfs4_client->cl_cb_flags to a generic flags field
  NFSD: Fix nfs4_verifier memory alignment
  NFSD: Fix warnings when NFSD_DEBUG is not defined
  nfsd: vfs_llseek() with 32 or 64 bit offsets (hashes)
  nfsd: rename 'int access' to 'int may_flags' in nfsd_open()
  ext4: return 32/64-bit dir name hash according to usage type
  fs: add new FMODE flags: FMODE_32bithash and FMODE_64bithash
  ...
2012-03-29 14:53:25 -07:00
Joe Perches ace36ad431 ext4: add no_printk argument validation, fix fallout
Add argument validation to debug functions.
Use ##__VA_ARGS__.

Fix format and argument mismatches.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-19 23:11:43 -04:00
Fan Yong d1f5273e9a ext4: return 32/64-bit dir name hash according to usage type
Traditionally ext2/3/4 has returned a 32-bit hash value from llseek()
to appease NFSv2, which can only handle a 32-bit cookie for seekdir()
and telldir().  However, this causes problems if there are 32-bit hash
collisions, since the NFSv2 server can get stuck resending the same
entries from the directory repeatedly.

Allow ext4 to return a full 64-bit hash (both major and minor) for
telldir to decrease the chance of hash collisions.  This still needs
integration on the NFS side.

Patch-updated-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
(blame me if something is not correct)

Signed-off-by: Fan Yong <yong.fan@whamcloud.com>
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-18 22:44:40 -04:00
Curt Wohlgemuth 4188188bdc ext4: add comments to definition of ext4_io_end_t
This should make it more clear what this structure is used
for, and how some of the (mutually exclusive) fields are
used to keep page cache references.

Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-05 10:40:22 -05:00
Jeff Moyer 491caa4363 ext4: fix race between sync and completed io work
The following command line will leave the aio-stress process unkillable
on an ext4 file system (in my case, mounted on /mnt/test):

aio-stress -t 20 -s 10 -O -S -o 2 -I 1000 /mnt/test/aiostress.3561.4 /mnt/test/aiostress.3561.4.20 /mnt/test/aiostress.3561.4.19 /mnt/test/aiostress.3561.4.18 /mnt/test/aiostress.3561.4.17 /mnt/test/aiostress.3561.4.16 /mnt/test/aiostress.3561.4.15 /mnt/test/aiostress.3561.4.14 /mnt/test/aiostress.3561.4.13 /mnt/test/aiostress.3561.4.12 /mnt/test/aiostress.3561.4.11 /mnt/test/aiostress.3561.4.10 /mnt/test/aiostress.3561.4.9 /mnt/test/aiostress.3561.4.8 /mnt/test/aiostress.3561.4.7 /mnt/test/aiostress.3561.4.6 /mnt/test/aiostress.3561.4.5 /mnt/test/aiostress.3561.4.4 /mnt/test/aiostress.3561.4.3 /mnt/test/aiostress.3561.4.2

This is using the aio-stress program from the xfstests test suite.
That particular command line tells aio-stress to do random writes to
20 files from 20 threads (one thread per file).  The files are NOT
preallocated, so you will get writes to random offsets within the
file, thus creating holes and extending i_size.  It also opens the
file with O_DIRECT and O_SYNC.

On to the problem.  When an I/O requires unwritten extent conversion,
it is queued onto the completed_io_list for the ext4 inode.  Two code
paths will pull work items from this list.  The first is the
ext4_end_io_work routine, and the second is ext4_flush_completed_IO,
which is called via the fsync path (and O_SYNC handling, as well).
There are two issues I've found in these code paths.  First, if the
fsync path beats the work routine to a particular I/O, the work
routine will free the io_end structure!  It does not take into account
the fact that the io_end may still be in use by the fsync path.  I've
fixed this issue by adding yet another IO_END flag, indicating that
the io_end is being processed by the fsync path.

The second problem is that the work routine will make an assignment to
io->flag outside of the lock.  I have witnessed this result in a hang
at umount.  Moving the flag setting inside the lock resolved that
problem.

The problem was introduced by commit b82e384c7b ("ext4: optimize
locking for end_io extent conversion"), which first appeared in 3.2.
As such, the fix should be backported to that release (probably along
with the unwritten extent conversion race fix).

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
CC: stable@kernel.org
2012-03-05 10:29:52 -05:00
Theodore Ts'o 5a916be1b3 ext4: make ext4_show_options() be table-driven
Consistently show mount options which are the non-default, so that
/proc/mounts accurately shows the mount options that would be
necessary to mount the file system in its current mode of operation.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-04 19:27:31 -05:00
Theodore Ts'o 39ef17f1b0 ext4: simplify handling of the errors=* mount options
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-03 17:56:23 -05:00
Theodore Ts'o c64db50e76 ext4: remove the I_VERSION mount flag and use the super_block flag instead
There's no point to have two bits that are set in parallel; so use the
MS_I_VERSION flag that is needed by the VFS anyway, and that way we
free up a bit in sbi->s_mount_opts.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-03-02 12:23:11 -05:00
Jeff Moyer 266991b138 ext4: fix race between unwritten extent conversion and truncate
The following comment in ext4_end_io_dio caught my attention:

	/* XXX: probably should move into the real I/O completion handler */
        inode_dio_done(inode);

The truncate code takes i_mutex, then calls inode_dio_wait.  Because the
ext4 code path above will end up dropping the mutex before it is
reacquired by the worker thread that does the extent conversion, it
seems to me that the truncate can happen out of order.  Jan Kara
mentioned that this might result in error messages in the system logs,
but that should be the extent of the "damage."

The fix is pretty straight-forward: don't call inode_dio_done until the
extent conversion is complete.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
2012-02-20 17:59:24 -05:00
Theodore Ts'o 856cbcf9a9 ext4: fix INCOMPAT feature codepoint reservation for INLINEDATA
In commit 9b90e5e028 I incorrectly reserved the wrong bit for
EXT4_FEATURE_INCOMPAT_INLINEDATA per the discussion on the linux-ext4
list on December 7, 2011.  The codepoint 0x2000 should be used for
EXT4_FEATURE_INCOMPAT_USE_META_CSUM, so INLINEDATA will be assigned
the value 0x8000.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20 17:53:01 -05:00
Theodore Ts'o 813e57276f ext4: fix race when setting bitmap_uptodate flag
In ext4_read_{inode,block}_bitmap() we were setting bitmap_uptodate()
before submitting the buffer for read.  The is bad, since we check
bitmap_uptodate() without locking the buffer, and so if another
process is racing with us, it's possible that they will think the
bitmap is uptodate even though the read has not completed yet,
resulting in inodes and blocks potentially getting allocated more than
once if we get really unlucky.

Addresses-Google-Bug: 2828254

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2012-02-20 17:52:46 -05:00
Theodore Ts'o ff9cb1c4ee Merge branch 'for_linus' into for_linus_merged
Conflicts:
	fs/ext4/ioctl.c
2012-01-10 11:54:07 -05:00