Commit graph

2713 commits

Author SHA1 Message Date
Jaegeuk Kim
03a8bb0e53 ext4/fscrypto: avoid RCU lookup in d_revalidate
As Al pointed, d_revalidate should return RCU lookup before using d_inode.
This was originally introduced by:
commit 34286d6662 ("fs: rcu-walk aware d_revalidate method").

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: stable <stable@vger.kernel.org>
2016-04-12 20:01:35 -07:00
Linus Torvalds
9f2394c9be Revert "ext4: allow readdir()'s of large empty directories to be interrupted"
This reverts commit 1028b55baf.

It's broken: it makes ext4 return an error at an invalid point, causing
the readdir wrappers to write the the position of the last successful
directory entry into the position field, which means that the next
readdir will now return that last successful entry _again_.

You can only return fatal errors (that terminate the readdir directory
walk) from within the filesystem readdir functions, the "normal" errors
(that happen when the readdir buffer fills up, for example) happen in
the iterorator where we know the position of the actual failing entry.

I do have a very different patch that does the "signal_pending()"
handling inside the iterator function where it is allowable, but while
that one passes all the sanity checks, I screwed up something like four
times while emailing it out, so I'm not going to commit it today.

So my track record is not good enough, and the stars will have to align
better before that one gets committed.  And it would be good to get some
review too, of course, since celestial alignments are always an iffy
debugging model.

IOW, let's just revert the commit that caused the problem for now.

Reported-by: Greg Thelen <gthelen@google.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-10 16:52:24 -07:00
Linus Torvalds
93061f390f These changes contains a fix for overlayfs interacting with some
(badly behaved) dentry code in various file systems.  These have been
 reviewed by Al and the respective file system mtinainers and are going
 through the ext4 tree for convenience.
 
 This also has a few ext4 encryption bug fixes that were discovered in
 Android testing (yes, we will need to get these sync'ed up with the
 fs/crypto code; I'll take care of that).  It also has some bug fixes
 and a change to ignore the legacy quota options to allow for xfstests
 regression testing of ext4's internal quota feature and to be more
 consistent with how xfs handles this case.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 bugfixes from Ted Ts'o:
 "These changes contains a fix for overlayfs interacting with some
  (badly behaved) dentry code in various file systems.  These have been
  reviewed by Al and the respective file system mtinainers and are going
  through the ext4 tree for convenience.

  This also has a few ext4 encryption bug fixes that were discovered in
  Android testing (yes, we will need to get these sync'ed up with the
  fs/crypto code; I'll take care of that).  It also has some bug fixes
  and a change to ignore the legacy quota options to allow for xfstests
  regression testing of ext4's internal quota feature and to be more
  consistent with how xfs handles this case"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: ignore quota mount options if the quota feature is enabled
  ext4 crypto: fix some error handling
  ext4: avoid calling dquot_get_next_id() if quota is not enabled
  ext4: retry block allocation for failed DIO and DAX writes
  ext4: add lockdep annotations for i_data_sem
  ext4: allow readdir()'s of large empty directories to be interrupted
  btrfs: fix crash/invalid memory access on fsync when using overlayfs
  ext4 crypto: use dget_parent() in ext4_d_revalidate()
  ext4: use file_dentry()
  ext4: use dget_parent() in ext4_file_open()
  nfs: use file_dentry()
  fs: add file_dentry()
  ext4 crypto: don't let data integrity writebacks fail with ENOMEM
  ext4: check if in-inode xattr is corrupted in ext4_expand_extra_isize_ea()
2016-04-07 17:22:20 -07:00
Kirill A. Shutemov
ea1754a084 mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage
Mostly direct substitution with occasional adjustment or removing
outdated comments.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Kirill A. Shutemov
09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00
Theodore Ts'o
c325a67c72 ext4: ignore quota mount options if the quota feature is enabled
Previously, ext4 would fail the mount if the file system had the quota
feature enabled and quota mount options (used for the older quota
setups) were present.  This broke xfstests, since xfs silently ignores
the usrquote and grpquota mount options if they are specified.  This
commit changes things so that we are consistent with xfs; having the
mount options specified is harmless, so no sense break users by
forbidding them.

Cc: stable@vger.kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-04-03 17:03:37 -04:00
Dan Carpenter
4762cc3fbb ext4 crypto: fix some error handling
We should be testing for -ENOMEM but the minus sign is missing.

Fixes: c9af28fdd4 ('ext4 crypto: don't let data integrity writebacks fail with ENOMEM')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-04-02 18:13:38 -04:00
Theodore Ts'o
8f0e8746b4 ext4: avoid calling dquot_get_next_id() if quota is not enabled
This should be fixed in the quota layer so we can test with the quota
mutex held, but for now, we need this to avoid tests from crashing the
kernel aborting the regression test suite.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-04-01 12:00:03 -04:00
Jan Kara
e84dfbe2bf ext4: retry block allocation for failed DIO and DAX writes
Currently if block allocation for DIO or DAX write fails due to ENOSPC,
we just returned it to userspace. However these ENOSPC errors can be
transient because the transaction freeing blocks has not yet committed.
This demonstrates as failures of generic/102 test when the filesystem is
mounted with 'dax' mount option.

Fix the problem by properly retrying the allocation in case of ENOSPC
error in get blocks functions used for direct IO.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
2016-04-01 02:07:22 -04:00
Theodore Ts'o
daf647d2dd ext4: add lockdep annotations for i_data_sem
With the internal Quota feature, mke2fs creates empty quota inodes and
quota usage tracking is enabled as soon as the file system is mounted.
Since quotacheck is no longer preallocating all of the blocks in the
quota inode that are likely needed to be written to, we are now seeing
a lockdep false positive caused by needing to allocate a quota block
from inside ext4_map_blocks(), while holding i_data_sem for a data
inode.  This results in this complaint:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&ei->i_data_sem);
                                lock(&s->s_dquot.dqio_mutex);
                                lock(&ei->i_data_sem);
   lock(&s->s_dquot.dqio_mutex);

Google-Bug-Id: 27907753

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2016-04-01 01:31:28 -04:00
Theodore Ts'o
1028b55baf ext4: allow readdir()'s of large empty directories to be interrupted
If a directory has a large number of empty blocks, iterating over all
of them can take a long time, leading to scheduler warnings and users
getting irritated when they can't kill a process in the middle of one
of these long-running readdir operations.  Fix this by adding checks to
ext4_readdir() and ext4_htree_fill_tree().

Reported-by: Benjamin LaHaise <bcrl@kvack.org>
Google-Bug-Id: 27880676
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-30 22:36:24 -04:00
Theodore Ts'o
3d43bcfef5 ext4 crypto: use dget_parent() in ext4_d_revalidate()
This avoids potential problems caused by a race where the inode gets
renamed out from its parent directory and the parent directory is
deleted while ext4_d_revalidate() is running.

Fixes: 28b4c26396
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2016-03-26 16:15:42 -04:00
Miklos Szeredi
c0a37d4878 ext4: use file_dentry()
EXT4 may be used as lower layer of overlayfs and accessing f_path.dentry
can lead to a crash.

Fix by replacing direct access of file->f_path.dentry with the
file_dentry() accessor, which will always return a native object.

Reported-by: Daniel Axtens <dja@axtens.net>
Fixes: 4bacc9c923 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
Fixes: ff978b09f9 ("ext4 crypto: move context consistency check to ext4_file_open()")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org> # v4.5
2016-03-26 16:14:42 -04:00
Miklos Szeredi
9dd78d8c9a ext4: use dget_parent() in ext4_file_open()
In f_op->open() lock on parent is not held, so there's no guarantee that
parent dentry won't go away at any time.

Even after this patch there's no guarantee that 'dir' will stay the parent
of 'inode', but at least it won't be freed while being used.

Fixes: ff978b09f9 ("ext4 crypto: move context consistency check to ext4_file_open()")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: <stable@vger.kernel.org> # v4.5
2016-03-26 16:14:41 -04:00
Theodore Ts'o
c9af28fdd4 ext4 crypto: don't let data integrity writebacks fail with ENOMEM
We don't want the writeback triggered from the journal commit (in
data=writeback mode) to cause the journal to abort due to
generic_writepages() returning an ENOMEM error.  In addition, if
fsync() fails with ENOMEM, most applications will probably not do the
right thing.

So if we are doing a data integrity sync, and ext4_encrypt() returns
ENOMEM, we will submit any queued I/O to date, and then retry the
allocation using GFP_NOFAIL.

Google-Bug-Id: 27641567

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-26 16:14:34 -04:00
Andy Lutomirski
121cef8f17 ext4: in ext4_dir_llseek, check syscall bitness directly
ext4 treats directory offsets differently for 32-bit and 64-bit callers.
Check the caller type using in_compat_syscall, not is_compat_task.  This
changes behavior on SPARC slightly.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Theodore Ts'o
9e92f48c34 ext4: check if in-inode xattr is corrupted in ext4_expand_extra_isize_ea()
We aren't checking to see if the in-inode extended attribute is
corrupted before we try to expand the inode's extra isize fields.

This can lead to potential crashes caused by the BUG_ON() check in
ext4_xattr_shift_entries().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-22 16:13:15 -04:00
Linus Torvalds
77d913178c Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull UDF and quota updates from Jan Kara:
 "This contains a rewrite of UDF handling of filename encoding to fix
  remaining overflow issues from Andrew Gabbasov and quota changes to
  support new Q_[X]GETNEXTQUOTA quotactl for VFS quota formats"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: Fix possible GPF due to uninitialised pointers
  ext4: Make Q_GETNEXTQUOTA work for quota in hidden inodes
  quota: Forbid Q_GETQUOTA and Q_GETNEXTQUOTA for frozen filesystem
  quota: Fix possible races during quota loading
  ocfs2: Implement get_next_id()
  quota_v2: Implement get_next_id() for V2 quota format
  quota: Add support for ->get_nextdqblk() for VFS quota
  udf: Merge linux specific translation into CS0 conversion function
  udf: Remove struct ustr as non-needed intermediate storage
  udf: Use separate buffer for copying split names
  udf: Adjust UDF_NAME_LEN to better reflect actual restrictions
  udf: Join functions for UTF8 and NLS conversions
  udf: Parameterize output length in udf_put_filename
  quota: Allow Q_GETQUOTA for frozen filesystem
  quota: Fixup comments about return value of Q_[X]GETNEXTQUOTA
2016-03-21 12:22:37 -07:00
Linus Torvalds
53d2e6976b xfs: Changes for 4.6-rc1
Change summary:
 o error propagation for direct IO failures fixes for both XFS and ext4
 o new quota interfaces and XFS implementation for iterating all the quota IDs
   in the filesystem
 o locking fixes for real-time device extent allocation
 o reduction of duplicate information in the xfs and vfs inode, saving roughly
   100 bytes of memory per cached inode.
 o buffer flag cleanup
 o rework of the writepage code to use the generic write clustering mechanisms
 o several fixes for inode flag based DAX enablement
 o rework of remount option parsing
 o compile time verification of on-disk format structure sizes
 o delayed allocation reservation overrun fixes
 o lots of little error handling fixes
 o small memory leak fixes
 o enable xfsaild freezing again
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Merge tag 'xfs-for-linus-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs updates from Dave Chinner:
 "There's quite a lot in this request, and there's some cross-over with
  ext4, dax and quota code due to the nature of the changes being made.

  As for the rest of the XFS changes, there are lots of little things
  all over the place, which add up to a lot of changes in the end.

  The major changes are that we've reduced the size of the struct
  xfs_inode by ~100 bytes (gives an inode cache footprint reduction of
  >10%), the writepage code now only does a single set of mapping tree
  lockups so uses less CPU, delayed allocation reservations won't
  overrun under random write loads anymore, and we added compile time
  verification for on-disk structure sizes so we find out when a commit
  or platform/compiler change breaks the on disk structure as early as
  possible.

  Change summary:

   - error propagation for direct IO failures fixes for both XFS and
     ext4
   - new quota interfaces and XFS implementation for iterating all the
     quota IDs in the filesystem
   - locking fixes for real-time device extent allocation
   - reduction of duplicate information in the xfs and vfs inode, saving
     roughly 100 bytes of memory per cached inode.
   - buffer flag cleanup
   - rework of the writepage code to use the generic write clustering
     mechanisms
   - several fixes for inode flag based DAX enablement
   - rework of remount option parsing
   - compile time verification of on-disk format structure sizes
   - delayed allocation reservation overrun fixes
   - lots of little error handling fixes
   - small memory leak fixes
   - enable xfsaild freezing again"

* tag 'xfs-for-linus-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (66 commits)
  xfs: always set rvalp in xfs_dir2_node_trim_free
  xfs: ensure committed is initialized in xfs_trans_roll
  xfs: borrow indirect blocks from freed extent when available
  xfs: refactor delalloc indlen reservation split into helper
  xfs: update freeblocks counter after extent deletion
  xfs: debug mode forced buffered write failure
  xfs: remove impossible condition
  xfs: check sizes of XFS on-disk structures at compile time
  xfs: ioends require logically contiguous file offsets
  xfs: use named array initializers for log item dumping
  xfs: fix computation of inode btree maxlevels
  xfs: reinitialise per-AG structures if geometry changes during recovery
  xfs: remove xfs_trans_get_block_res
  xfs: fix up inode32/64 (re)mount handling
  xfs: fix format specifier , should be %llx and not %llu
  xfs: sanitize remount options
  xfs: convert mount option parsing to tokens
  xfs: fix two memory leaks in xfs_attr_list.c error paths
  xfs: XFS_DIFLAG2_DAX limited by PAGE_SIZE
  xfs: dynamically switch modes when XFS_DIFLAG2_DAX is set/cleared
  ...
2016-03-21 11:53:05 -07:00
Linus Torvalds
faeb20ecfa Performance improvements in SEEK_DATA and xattr scalability
improvements, plus a lot of clean ups 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 Ted Ts'o:
 "Performance improvements in SEEK_DATA and xattr scalability
  improvements, plus a lot of clean ups and bug fixes"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (38 commits)
  ext4: clean up error handling in the MMP support
  jbd2: do not fail journal because of frozen_buffer allocation failure
  ext4: use __GFP_NOFAIL in ext4_free_blocks()
  ext4: fix compile error while opening the macro DOUBLE_CHECK
  ext4: print ext4 mount option data_err=abort correctly
  ext4: fix NULL pointer dereference in ext4_mark_inode_dirty()
  ext4: drop unneeded BUFFER_TRACE in ext4_delete_inline_entry()
  ext4: fix misspellings in comments.
  jbd2: fix FS corruption possibility in jbd2_journal_destroy() on umount path
  ext4: more efficient SEEK_DATA implementation
  ext4: cleanup handling of bh->b_state in DAX mmap
  ext4: return hole from ext4_map_blocks()
  ext4: factor out determining of hole size
  ext4: fix setting of referenced bit in ext4_es_lookup_extent()
  ext4: remove i_ioend_count
  ext4: simplify io_end handling for AIO DIO
  ext4: move trans handling and completion deferal out of _ext4_get_block
  ext4: rename and split get blocks functions
  ext4: use i_mutex to serialize unaligned AIO DIO
  ext4: pack ioend structure better
  ...
2016-03-17 16:31:18 -07:00
Linus Torvalds
70477371dc Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto update from Herbert Xu:
 "Here is the crypto update for 4.6:

  API:
   - Convert remaining crypto_hash users to shash or ahash, also convert
     blkcipher/ablkcipher users to skcipher.
   - Remove crypto_hash interface.
   - Remove crypto_pcomp interface.
   - Add crypto engine for async cipher drivers.
   - Add akcipher documentation.
   - Add skcipher documentation.

  Algorithms:
   - Rename crypto/crc32 to avoid name clash with lib/crc32.
   - Fix bug in keywrap where we zero the wrong pointer.

  Drivers:
   - Support T5/M5, T7/M7 SPARC CPUs in n2 hwrng driver.
   - Add PIC32 hwrng driver.
   - Support BCM6368 in bcm63xx hwrng driver.
   - Pack structs for 32-bit compat users in qat.
   - Use crypto engine in omap-aes.
   - Add support for sama5d2x SoCs in atmel-sha.
   - Make atmel-sha available again.
   - Make sahara hashing available again.
   - Make ccp hashing available again.
   - Make sha1-mb available again.
   - Add support for multiple devices in ccp.
   - Improve DMA performance in caam.
   - Add hashing support to rockchip"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (116 commits)
  crypto: qat - remove redundant arbiter configuration
  crypto: ux500 - fix checks of error code returned by devm_ioremap_resource()
  crypto: atmel - fix checks of error code returned by devm_ioremap_resource()
  crypto: qat - Change the definition of icp_qat_uof_regtype
  hwrng: exynos - use __maybe_unused to hide pm functions
  crypto: ccp - Add abstraction for device-specific calls
  crypto: ccp - CCP versioning support
  crypto: ccp - Support for multiple CCPs
  crypto: ccp - Remove check for x86 family and model
  crypto: ccp - memset request context to zero during import
  lib/mpi: use "static inline" instead of "extern inline"
  lib/mpi: avoid assembler warning
  hwrng: bcm63xx - fix non device tree compatibility
  crypto: testmgr - allow rfc3686 aes-ctr variants in fips mode.
  crypto: qat - The AE id should be less than the maximal AE number
  lib/mpi: Endianness fix
  crypto: rockchip - add hash support for crypto engine in rk3288
  crypto: xts - fix compile errors
  crypto: doc - add skcipher API documentation
  crypto: doc - update AEAD AD handling
  ...
2016-03-17 11:22:54 -07:00
vikram.jadhav07
0304688676 ext4: clean up error handling in the MMP support
There is memory leak as both caller function kmmpd() and callee
read_mmp_block() not releasing bh_check  (i.e buffer_head).
Given patch fixes this problem.

[ Additional changes suggested by Andreas Dilger -- TYT ]

Signed-off-by: Jadhav Vikram <vikramjadhavpucsd2007@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-13 17:56:52 -04:00
Konstantin Khlebnikov
adb7ef600c ext4: use __GFP_NOFAIL in ext4_free_blocks()
This might be unexpected but pages allocated for sbi->s_buddy_cache are
charged to current memory cgroup. So, GFP_NOFS allocation could fail if
current task has been killed by OOM or if current memory cgroup has no
free memory left. Block allocator cannot handle such failures here yet.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-13 17:29:06 -04:00
Aihua Zhang
a2821e34df ext4: fix compile error while opening the macro DOUBLE_CHECK
the error is:
    fs/ext4/mballoc.c:475:43: error: 'struct ext4_group_info' has
no member named 'bb_bitmap'.
    so, the definition of macro DOUBLE_CHECK should before
'struct ext4_group_info', I fixed it, and I moved the macro
AGGRESSIVE_CHECK together, because I think they shoule be together.

Signed-off-by: Aihua Zhang <zhangaihua1@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-13 17:18:12 -04:00
Ales Novak
7915a861c0 ext4: print ext4 mount option data_err=abort correctly
If data_err=abort option is specified for an ext3/ext4 mount,
/proc/mounts does show it as "(null)". This is caused by token2str()
returning NULL for Opt_data_err_abort (due to its pattern containing
'=').

Signed-off-by: Ales Novak <alnovak@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-12 21:55:50 -05:00
Eryu Guan
5e1021f2b6 ext4: fix NULL pointer dereference in ext4_mark_inode_dirty()
ext4_reserve_inode_write() in ext4_mark_inode_dirty() could fail on
error (e.g. EIO) and iloc.bh can be NULL in this case. But the error is
ignored in the following "if" condition and ext4_expand_extra_isize()
might be called with NULL iloc.bh set, which triggers NULL pointer
dereference.

This is uncovered by commit 8b4953e13f ("ext4: reserve code points for
the project quota feature"), which enlarges the ext4_inode size, and
run the following script on new kernel but with old mke2fs:

  #/bin/bash
  mnt=/mnt/ext4
  devname=ext4-error
  dev=/dev/mapper/$devname
  fsimg=/home/fs.img

  trap cleanup 0 1 2 3 9 15

  cleanup()
  {
          umount $mnt >/dev/null 2>&1
          dmsetup remove $devname
          losetup -d $backend_dev
          rm -f $fsimg
          exit 0
  }

  rm -f $fsimg
  fallocate -l 1g $fsimg
  backend_dev=`losetup -f --show $fsimg`
  devsize=`blockdev --getsz $backend_dev`

  good_tab="0 $devsize linear $backend_dev 0"
  error_tab="0 $devsize error $backend_dev 0"

  dmsetup create $devname --table "$good_tab"

  mkfs -t ext4 $dev
  mount -t ext4 -o errors=continue,strictatime $dev $mnt

  dmsetup load $devname --table "$error_tab" && dmsetup resume $devname
  echo 3 > /proc/sys/vm/drop_caches
  ls -l $mnt
  exit 0

[ Patch changed to simplify the function a tiny bit. -- Ted ]

Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-12 21:40:32 -05:00
Geliang Tang
a8ed9b8695 ext4: drop unneeded BUFFER_TRACE in ext4_delete_inline_entry()
BUFFER_TRACE info "call ext4_handle_dirty_metadata" doesn't match the
code, so drop it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-10 00:18:57 -05:00
Adam Buchbinder
b8a07463c8 ext4: fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 23:49:05 -05:00
Jan Kara
2d90c160e5 ext4: more efficient SEEK_DATA implementation
Using SEEK_DATA in a huge sparse file can easily lead to sotflockups as
ext4_seek_data() iterates hole block-by-block. Fix the problem by using
returned hole size from ext4_map_blocks() and thus skip the hole in one
go.

Update also SEEK_HOLE implementation to follow the same pattern as
SEEK_DATA to make future maintenance easier.

Furthermore we add cond_resched() to both ext4_seek_data() and
ext4_seek_hole() to avoid softlockups in case evil user creates huge
fragmented file and we have to go through lots of extents.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 23:11:13 -05:00
Jan Kara
e3fb8eb14e ext4: cleanup handling of bh->b_state in DAX mmap
ext4_dax_mmap_get_block() updates bh->b_state directly instead of using
ext4_update_bh_state(). This is mostly a cosmetic issue since DAX code
always passes on-stack buffer_head but clean this up to make code more
uniform.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 23:03:27 -05:00
Jan Kara
facab4d971 ext4: return hole from ext4_map_blocks()
Currently, ext4_map_blocks() just returns 0 when it finds a hole and
allocation is not requested. However we have all the information
available to tell how large the hole actually is and there are callers
of ext4_map_blocks() which would save some block-by-block hole iteration
if they knew this information. So fill in struct ext4_map_blocks even
for holes with the information we have. We keep returning 0 for holes to
maintain backward compatibility of the function.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 22:54:00 -05:00
Jan Kara
140a52508a ext4: factor out determining of hole size
ext4_ext_put_gap_in_cache() determines hole size in the extent tree,
then trims this with possible delayed allocated blocks, and inserts the
result into the extent status tree. Factor out determination of the size
of the hole in the extent tree as we will need this information in
ext4_ext_map_blocks() as well.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 22:46:57 -05:00
Linus Torvalds
718e47a573 This fixes a regression which crept in v4.5-rc5.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fix from Ted Ts'o:
 "This fixes a regression which crept in v4.5-rc5"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: iterate over buffer heads correctly in move_extent_per_page()
2016-03-09 19:33:05 -08:00
Jan Kara
87d8a74b56 ext4: fix setting of referenced bit in ext4_es_lookup_extent()
We were setting referenced bit on the extent structure we return from
ext4_es_lookup_extent() which is just a private structure on stack. Thus
setting had no effect. Set the bit in the structure in the status tree
instead.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 22:26:55 -05:00
Eryu Guan
6ffe77bad5 ext4: iterate over buffer heads correctly in move_extent_per_page()
In commit bcff24887d ("ext4: don't read blocks from disk after extents
being swapped") bh is not updated correctly in the for loop and wrong
data has been written to disk. generic/324 catches this on sub-page
block size ext4.

Fixes: bcff24887d ("ext4: don't read blocks from disk after extentsbeing swapped")
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-09 21:37:53 -05:00
Jan Kara
600be30a8b ext4: remove i_ioend_count
Remove counter of pending io ends as it is unused.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-08 23:39:21 -05:00
Jan Kara
109811c20f ext4: simplify io_end handling for AIO DIO
When mapping blocks for direct IO, we allocate io_end structure before
mapping blocks and store pointer to it in the inode. This creates a
requirement that any AIO DIO using io_end must be protected by i_mutex.
This created problems in the past with dioread_nolock mode which was
corrupting io_end pointers. Also io_end is allocated unnecessarily in
case where we don't need to convert any extents (which is a common case
for example when overwriting file).

We fix the problem by allocating io_end only once we return unwritten
extent from block mapping function for AIO DIO (so we can save some
pointless io_end allocations) and we pass pointer to it in bh->b_private
which generic DIO code later passes to our end IO callback. That way we
remove any need for global pointer to io_end structure and thus fix the
races.

The downside of this change is that the checking for unwritten IO in
flight in ext4_extents_can_be_merged() is more racy since we now
increment i_unwritten / set EXT4_STATE_DIO_UNWRITTEN only after dropping
i_data_sem. However the check has been racy already before because
ext4_writepages() already increment i_unwritten after dropping
i_data_sem and reserved blocks save us from hitting ENOSPC in the worst
case.

Signed-off-by: Jan Kara <jack@suse.cz>
2016-03-08 23:36:46 -05:00
Jan Kara
efe70c2951 ext4: move trans handling and completion deferal out of _ext4_get_block
There is no need to handle starting of a transaction and deferal of DIO
completion in _ext4_get_block() function. We can move this out to get
block functions for direct IO that need it. That way we can add stricter
checks verifying things work as we expect.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-08 23:35:46 -05:00
Jan Kara
705965bd6d ext4: rename and split get blocks functions
Rename ext4_get_blocks_write() to ext4_get_blocks_unwritten() to better
describe what it does. Also split out get blocks functions for direct
IO. Later we move functionality from _ext4_get_blocks() there. There's no
functional change in this patch.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-08 23:08:10 -05:00
Jan Kara
e142d05263 ext4: use i_mutex to serialize unaligned AIO DIO
Currently we've used hashed aio_mutex to serialize unaligned AIO DIO.
However the code cleanups that happened after 2011 when the lock was
introduced made aio_mutex acquired at almost the same places where we
already have exclusion using i_mutex. So just use i_mutex for the
exclusion of unaligned AIO DIO.

The change moves waiting for pending unwritten extent conversion under
i_mutex. That makes special handling of O_APPEND writes unnecessary and
also avoids possible livelocking of unaligned AIO DIO with aligned one
(nothing was preventing contiguous stream of aligned AIO DIOs to let
unaligned AIO DIO wait forever).

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-08 22:44:50 -05:00
Jan Kara
3bd6ad7b68 ext4: pack ioend structure better
On 64-bit architectures we have two 4-byte holes in struct ext4_io_end.
Order entries better to avoid this and thus make the structure occupy
64 instead of 72 bytes for 64-bit architectures.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-03-08 22:26:39 -05:00
Jan Kara
74c66bcb7e ext4: Fix data exposure after failed AIO DIO
When AIO DIO fails e.g. due to IO error, we must not convert unwritten
extents as that will expose uninitialized data. Handle this case
by clearing unwritten flag from io_end in case of error and thus
preventing extent conversion.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-29 08:36:38 +11:00
Linus Torvalds
691429e13d Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
 "10 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  dax: move writeback calls into the filesystems
  dax: give DAX clearing code correct bdev
  ext4: online defrag not supported with DAX
  ext2, ext4: only set S_DAX for regular inodes
  block: disable block device DAX by default
  ocfs2: unlock inode if deleting inode from orphan fails
  mm: ASLR: use get_random_long()
  drivers: char: random: add get_random_long()
  mm: numa: quickly fail allocations for NUMA balancing on full nodes
  mm: thp: fix SMP race condition between THP page fault and MADV_DONTNEED
2016-02-27 12:46:16 -08:00
Ross Zwisler
1e9d180ba3 ext2, ext4: fix issue with missing journal entry in ext4_dax_mkwrite()
As it is currently written ext4_dax_mkwrite() assumes that the call into
__dax_mkwrite() will not have to do a block allocation so it doesn't create
a journal entry.  For a read that creates a zero page to cover a hole
followed by a write that actually allocates storage this is incorrect.  The
ext4_dax_mkwrite() -> __dax_mkwrite() -> __dax_fault() path calls
get_blocks() to allocate storage.

Fix this by having the ->page_mkwrite fault handler call ext4_dax_fault()
as this function already has all the logic needed to allocate a journal
entry and call __dax_fault().

Also update the ext2 fault handlers in this same way to remove duplicate
code and keep the logic between ext2 and ext4 the same.

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-02-27 14:01:16 -05:00
Ross Zwisler
7f6d5b529b dax: move writeback calls into the filesystems
Previously calls to dax_writeback_mapping_range() for all DAX filesystems
(ext2, ext4 & xfs) were centralized in filemap_write_and_wait_range().

dax_writeback_mapping_range() needs a struct block_device, and it used
to get that from inode->i_sb->s_bdev.  This is correct for normal inodes
mounted on ext2, ext4 and XFS filesystems, but is incorrect for DAX raw
block devices and for XFS real-time files.

Instead, call dax_writeback_mapping_range() directly from the filesystem
->writepages function so that it can supply us with a valid block
device.  This also fixes DAX code to properly flush caches in response
to sync(2).

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-27 10:28:52 -08:00
Ross Zwisler
73f34a5e2c ext4: online defrag not supported with DAX
Online defrag operations for ext4 are hard coded to use the page cache.
See ext4_ioctl() -> ext4_move_extents() -> move_extent_per_page()

When combined with DAX I/O, which circumvents the page cache, this can
result in data corruption.  This was observed with xfstests ext4/307 and
ext4/308.

Fix this by only allowing online defrag for non-DAX files.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-27 10:28:52 -08:00
Ross Zwisler
0a6cf9137d ext2, ext4: only set S_DAX for regular inodes
When S_DAX is set on an inode we assume that if there are pages attached
to the mapping (mapping->nrpages != 0), those pages are clean zero pages
that were used to service reads from holes.  Any dirty data associated
with the inode should be in the form of DAX exceptional entries
(mapping->nrexceptional) that is written back via
dax_writeback_mapping_range().

With the current code, though, this isn't always true.  For example,
ext2 and ext4 directory inodes can have S_DAX set, but have their dirty
data stored as dirty page cache entries.  For these types of inodes,
having S_DAX set doesn't really make sense since their I/O doesn't
actually happen through the DAX code path.

Instead, only allow S_DAX to be set for regular inodes for ext2 and
ext4.  This allows us to have strict DAX vs non-DAX paths in the
writeback code.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-27 10:28:52 -08:00
Eric Whitney
29c6eaffc8 ext4: trim unused parameter from convert_initialized_extent()
The flags parameter is also unused.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-02-22 22:58:55 -05:00
Andreas Gruenbacher
6048c64b26 mbcache: add reusable flag to cache entries
To reduce amount of damage caused by single bad block, we limit number
of inodes sharing an xattr block to 1024. Thus there can be more xattr
blocks with the same contents when there are lots of files with the same
extended attributes. These xattr blocks naturally result in hash
collisions and can form long hash chains and we unnecessarily check each
such block only to find out we cannot use it because it is already
shared by too many inodes.

Add a reusable flag to cache entries which is cleared when a cache entry
has reached its maximum refcount.  Cache entries which are not marked
reusable are skipped by mb_cache_entry_find_{first,next}. This
significantly speeds up mbcache when there are many same xattr blocks.
For example for xattr-bench with 5 values and each process handling
20000 files, the run for 64 processes is 25x faster with this patch.
Even for 8 processes the speedup is almost 3x. We have also verified
that for situations where there is only one xattr block of each kind,
the patch doesn't have a measurable cost.

[JK: Remove handling of setting the same value since it is not needed
anymore, check for races in e_reusable setting, improve changelog,
add measurements]

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-02-22 22:44:04 -05:00
Jan Kara
3fd164629d ext4: shortcut setting of xattr to the same value
When someone tried to set xattr to the same value (i.e., not changing
anything) we did all the work of removing original xattr, possibly
breaking references to shared xattr block, inserting new xattr, and
merging xattr blocks again. Since this is not so rare operation and it
is relatively cheap for us to detect this case, check for this and
shortcut xattr setting in that case.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-02-22 22:43:04 -05:00