When ext4_rename() overwrites an already existing file, call
ext4_alloc_da_blocks() before starting the journal handle which
actually does the rename, instead of doing this afterwards. This
improves the likelihood that the contents will survive a crash if an
application replaces a file using the sequence:
1) write replacement contents to foo.new
2) <omit fsync of foo.new>
3) rename foo.new to foo
It is still not a guarantee, since ext4_alloc_da_blocks() is *not*
doing a file integrity sync; this means if foo.new is a very large
file, it may not be completely flushed out to disk.
However, for files smaller than a megabyte or so, any dirty pages
should be flushed out before we do the rename operation, and so at the
next journal commit, the CACHE FLUSH command will make sure al of
these pages are safely on the disk platter.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_rename(), don't start the journal handle until the the
directory entries have been successfully looked up.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Pull second set of VFS changes from Al Viro:
"Assorted f_pos race fixes, making do_splice_direct() safe to call with
i_mutex on parent, O_TMPFILE support, Jeff's locks.c series,
->d_hash/->d_compare calling conventions changes from Linus, misc
stuff all over the place."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
Document ->tmpfile()
ext4: ->tmpfile() support
vfs: export lseek_execute() to modules
lseek_execute() doesn't need an inode passed to it
block_dev: switch to fixed_size_llseek()
cpqphp_sysfs: switch to fixed_size_llseek()
tile-srom: switch to fixed_size_llseek()
proc_powerpc: switch to fixed_size_llseek()
ubi/cdev: switch to fixed_size_llseek()
pci/proc: switch to fixed_size_llseek()
isapnp: switch to fixed_size_llseek()
lpfc: switch to fixed_size_llseek()
locks: give the blocked_hash its own spinlock
locks: add a new "lm_owner_key" lock operation
locks: turn the blocked_list into a hashtable
locks: convert fl_link to a hlist_node
locks: avoid taking global lock if possible when waking up blocked waiters
locks: protect most of the file_lock handling with i_lock
locks: encapsulate the fl_link list handling
locks: make "added" in __posix_lock_file a bool
...
Both ext3 and ext4 htree_dirblock_to_tree() is just filling the
in-core rbtree for use by call_filldir(). All updates of ->f_pos are
done by the latter; bumping it here (on error) is obviously wrong - we
might very well have it nowhere near the block we'd found an error in.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
Zach reported a problem that if inline data is enabled, we don't
tell the difference between the offset of '.' and '..'. And a
getdents will fail if the user only want to get '.' and what's worse,
if there is a conversion happens when the user calls getdents
many times, he/she may get the same entry twice.
In theory, a dir block would also fail if it is converted to a
hashed-index based dir since f_pos will become a hash value, not the
real one, but it doesn't happen. And a deep investigation shows that
we uses a hash based solution even for a normal dir if the dir_index
feature is enabled.
So this patch just adds a new htree_inlinedir_to_tree for inline dir,
and if we find that the hash index is supported, we will do like what
we do for a dir block.
Reported-by: Zach Brown <zab@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Inode allocation transaction is pretty heavy (246 credits with quotas
and extents before previous patch, still around 200 after it). This is
mostly due to credits required for allocation of quota structures
(credits there are heavily overestimated but it's difficult to make
better estimates if we don't want to wire non-trivial assumptions about
quota format into filesystem).
So move quota initialization out of allocation transaction. That way
transaction for quota structure allocation will be started only if we
need to look up quota structure on disk (rare) and furthermore it will
be started for each quota type separately, not for all of them at once.
This reduces maximum transaction size to 34 is most cases and to 73 in
the worst case.
[ Modified by tytso to clean up the cleanup paths for error handling.
Also use a separate call to ext4_std_error() for each failure so it
is easier for someone who is debugging a problem in this function to
determine which function call failed. ]
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Pull vfs pile (part one) from Al Viro:
"Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
locking violations, etc.
The most visible changes here are death of FS_REVAL_DOT (replaced with
"has ->d_weak_revalidate()") and a new helper getting from struct file
to inode. Some bits of preparation to xattr method interface changes.
Misc patches by various people sent this cycle *and* ocfs2 fixes from
several cycles ago that should've been upstream right then.
PS: the next vfs pile will be xattr stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
saner proc_get_inode() calling conventions
proc: avoid extra pde_put() in proc_fill_super()
fs: change return values from -EACCES to -EPERM
fs/exec.c: make bprm_mm_init() static
ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
ocfs2: fix possible use-after-free with AIO
ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
target: writev() on single-element vector is pointless
export kernel_write(), convert open-coded instances
fs: encode_fh: return FILEID_INVALID if invalid fid_type
kill f_vfsmnt
vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
nfsd: handle vfs_getattr errors in acl protocol
switch vfs_getattr() to struct path
default SET_PERSONALITY() in linux/elf.h
ceph: prepopulate inodes only when request is aborted
d_hash_and_lookup(): export, switch open-coded instances
9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
9p: split dropping the acls from v9fs_set_create_acl()
...
the "punch hole" functionality for inodes that are not using extent
maps.
In the bug fix category, we fixed some races in the AIO and fstrim
code, and some potential NULL pointer dereferences and memory leaks in
error handling code paths.
In the optimization category, we fixed a performance regression in the
jbd2 layer introduced by commit d9b0193 (introduced in v3.0) which
shows up in the AIM7 benchmark. We also further optimized jbd2 by
minimize the amount of time that transaction handles are held active.
This patch series also features some additional enhancement of the
extent status tree, which is now used to cache extent information in a
more efficient/compact form than what we use on-disk.
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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 one new feature added in this patch series is the ability to use
the "punch hole" functionality for inodes that are not using extent
maps.
In the bug fix category, we fixed some races in the AIO and fstrim
code, and some potential NULL pointer dereferences and memory leaks in
error handling code paths.
In the optimization category, we fixed a performance regression in the
jbd2 layer introduced by commit d9b01934d5 ("jbd: fix fsync() tid
wraparound bug", introduced in v3.0) which shows up in the AIM7
benchmark. We also further optimized jbd2 by minimize the amount of
time that transaction handles are held active.
This patch series also features some additional enhancement of the
extent status tree, which is now used to cache extent information in a
more efficient/compact form than what we use on-disk."
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (65 commits)
ext4: fix free clusters calculation in bigalloc filesystem
ext4: no need to remove extent if len is 0 in ext4_es_remove_extent()
ext4: fix xattr block allocation/release with bigalloc
ext4: reclaim extents from extent status tree
ext4: adjust some functions for reclaiming extents from extent status tree
ext4: remove single extent cache
ext4: lookup block mapping in extent status tree
ext4: track all extent status in extent status tree
ext4: let ext4_ext_map_blocks return EXT4_MAP_UNWRITTEN flag
ext4: rename and improbe ext4_es_find_extent()
ext4: add physical block and status member into extent status tree
ext4: refine extent status tree
ext4: use ERR_PTR() abstraction for ext4_append()
ext4: refactor code to read directory blocks into ext4_read_dirblock()
ext4: add debugging context for warning in ext4_da_update_reserve_space()
ext4: use KERN_WARNING for warning messages
jbd2: use module parameters instead of debugfs for jbd_debug
ext4: use module parameters instead of debugfs for mballoc_debug
ext4: start handle at the last possible moment when creating inodes
ext4: fix the number of credits needed for acl ops with inline data
...
Use ERR_PTR()/IS_ERR() abstraction instead of passing in a separate
pointer to an integer for the error code, as a code cleanup.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The code to read in directory blocks and verify their metadata
checksums was replicated in ten different places across
fs/ext4/namei.c, and the code was buggy in subtle ways in a number of
those replicated sites. In some cases, ext4_error() was called with a
training newline. In others, in particularly in empty_dir(), it was
possible to call ext4_dirent_csum_verify() on an index block, which
would trigger false warnings requesting the system adminsitrator to
run e2fsck.
By refactoring the code, we make the code more readable, as well as
shrinking the compiled object file by over 700 bytes and 50 lines of
code.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In ext4_{create,mknod,mkdir,symlink}(), don't start the journal handle
until the inode has been succesfully allocated. In order to do this,
we need to start the handle in the ext4_new_inode(). So create a new
variant of this function, ext4_new_inode_start_handle(), so the handle
can be created at the last possible minute, before we need to modify
the inode allocation bitmap block.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The ext4_unlink() and ext4_rmdir() don't actually release the blocks
associated with the file/directory. This gets done in a separate jbd2
handle called via ext4_evict_inode(). Thus, we don't need to reserve
lots of journal credits for the truncate.
Note that using too many journal credits is non-optimal because it can
leading to the journal transmit getting closed too early, before it is
strictly necessary.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Don't start the jbd2 transaction handle until after the directory
entry has been found, to minimize the amount of time that a handle is
held active.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Don't start the jbd2 transaction handle until after the directory
entry has been found, to minimize the amount of time that a handle is
held active.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
So we can better understand what bits of ext4 are responsible for
long-running jbd2 handles, use jbd2__journal_start() so we can pass
context information for logging purposes.
The recommended way for finding the longer-running handles is:
T=/sys/kernel/debug/tracing
EVENT=$T/events/jbd2/jbd2_handle_stats
echo "interval > 5" > $EVENT/filter
echo 1 > $EVENT/enable
./run-my-fs-benchmark
cat $T/trace > /tmp/problem-handles
This will list handles that were active for longer than 20ms. Having
longer-running handles is bad, because a commit started at the wrong
time could stall for those 20+ milliseconds, which could delay an
fsync() or an O_SYNC operation. Here is an example line from the
trace file describing a handle which lived on for 311 jiffies, or over
1.2 seconds:
postmark-2917 [000] .... 196.435786: jbd2_handle_stats: dev 254,32
tid 570 type 2 line_no 2541 interval 311 sync 0 requested_blocks 1
dirtied_blocks 0
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
brelse() and ext4_journal_force_commit() are both inlined and able
to handle NULL.
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
After commit 978fef9 (create __ext4_insert_dentry for dir entry
insertion), 'reclen' is not used anymore.
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Commit b0336e8d (ext4: calculate and verify checksums of directory
leaf blocks) and commit dbe89444 (ext4: Calculate and verify checksums
for htree nodes) forget to release buffer when checksum failed, at
some places.
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
This macro, initially introduced by ext2 in v0.99.15, does not
have any users from the beginning. It has been removed in later
ext2 version but still remains in the code of ext3, ext4, ocfs2.
Remove this macro there.
Cc: Jan Kara <jack@suse.cz>
Cc: linux-ext4@vger.kernel.org
Cc: ocfs2-devel@oss.oracle.com
Acked-by: Mark Fasheh <mfasheh@suse.de>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This fixes a buffer cache leak when creating a directory, introduced
in commit a774f9c20.
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Tao Ma <boyu.mt@taobao.com>
If checksum fails, we should also release the buffer
read from previous iteration.
Signed-off-by: Guo Chao <yan@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>-
Cc: stable@vger.kernel.org
--
fs/ext4/namei.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
When trying to mount a file system which does not contain a journal,
but which does have a orphan list containing an inode which needs to
be truncated, the mount call with hang forever in
ext4_orphan_cleanup() because ext4_orphan_del() will return
immediately without removing the inode from the orphan list, leading
to an uninterruptible loop in kernel code which will busy out one of
the CPU's on the system.
This can be trivially reproduced by trying to mount the file system
found in tests/f_orphan_extents_inode/image.gz from the e2fsprogs
source tree. If a malicious user were to put this on a USB stick, and
mount it on a Linux desktop which has automatic mounts enabled, this
could be considered a potential denial of service attack. (Not a big
deal in practice, but professional paranoids worry about such things,
and have even been known to allocate CVE numbers for such problems.)
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Cc: stable@vger.kernel.org
Ted has sent out a RFC about removing this feature. Eric and Jan
confirmed that both RedHat and SUSE enable this feature in all their
product. David also said that "As far as I know, it's enabled in all
Android kernels that use ext4." So it seems OK for us.
And what's more, as inline data depends its implementation on xattr,
and to be frank, I don't run any test again inline data enabled while
xattr disabled. So I think we should add inline data and remove this
config option in the same release.
[ The savings if you disable CONFIG_EXT4_FS_XATTR is only 27k, which
isn't much in the grand scheme of things. Since no one seems to be
testing this configuration except for some automated compile farms, on
balance we are better removing this config option, and so that it is
effectively always enabled. -- tytso ]
Cc: David Brown <davidb@codeaurora.org>
Cc: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In case we rename a directory, ext4_rename has to read the dir block
and change its dotdot's information. The old ext4_rename encapsulated
the dir_block read into itself. So this patch adds a new function
ext4_get_first_dir_block() which gets the dir buffer information so
the ext4_rename can handle it properly. As it will also change the
parent inode number, we return the parent_de so that ext4_rename() can
handle it more easily.
ext4_find_entry is also changed so that the caller(rename) can tell
whether the found entry is an inlined one or not and journaling the
corresponding buffer head.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
empty_dir is used when deleting a dir. So it should handle inline dir
properly.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently ext4_delete_entry() is used only for dir entry removing from
a dir block. So let us create a new function
ext4_generic_delete_entry and this function takes a entry_buf and a
buf_size so that it can be used for inline data.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Create a new function ext4_find_inline_entry() to handle the case of
inline data.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
search_dirblock is used to search a dir block, but the code is almost
the same for searching an inline dir.
So create a new fuction search_dir and let search_dirblock call it.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch let add_dir_entry handle the inline data case. So the
dir is initialized as inline dir first and then we can try to add
some files to it, when the inline space can't hold all the entries,
a dir block will be created and the dir entry will be moved to it.
Also for an inlined dir, "." and ".." are removed and we only use
4 bytes to store the parent inode number. These 2 entries will be
added when we convert an inline dir to a block-based one.
[ Folded in patch from Dan Carpenter to remove an unused variable. ]
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The old add_dirent_to_buf handles all the work related to the
work of adding dir entry to a dir block. Now we have inline data,
so create 2 new function __ext4_find_dest_de and __ext4_insert_dentry
that do the real work and let add_dirent_to_buf call them.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The __ext4_check_dir_entry() function() is used to check whether the
de is over the block boundary. Now with inline data, it could be
within the block boundary while exceeds the inode size. So check this
function to check the overflow more precisely.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Currently, the initialization of dot and dotdot are encapsulated in
ext4_mkdir and also bond with dir_block. So create a new function
named ext4_init_new_dir and the initialization is moved to
ext4_init_dot_dotdot. Now it will called either in the normal non-inline
case(rec_len of ".." will cover the whole block) or when we converting an
inline dir to a block(rec len of ".." will be the real length). The start
of the next entry is also returned for inline dir usage.
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
During a directory entry lookup of a hashed directory, if the
hash-based lookup functions fail and we fall back to a linear scan,
don't try to verify the dirent checksum on the internal nodes of the
hash tree because they don't store a checksum in a hidden dirent like
the leaf nodes do.
Reported-by: George Spelvin <linux@horizon.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If there is no space for a checksum in a directory leaf node,
previously we would use EXT4_ERROR_INODE() which would mark the file
system as inconsistent. While it would be nice to use e2fsck -D, it
certainly isn't required, so just print a warning using
ext4_warning().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
When ext4_bread() returns NULL and err is set to zero, this means
there is no phyical block mapped to the specified logical block
number. (Previous to commit 90b0a97323, err was uninitialized in this
case, which caused other problems.)
The directory handling routines use ext4_bread() in many places, the
fact that ext4_bread() now returns NULL with err set to zero could
cause problems since a number of these functions will simply return
the value of err if the result of ext4_bread() was the NULL pointer,
causing the caller of the function to think that the function was
successful.
Since directories should never contain holes, this case can only
happen if the file system is corrupted. This commit audits all of the
callers of ext4_bread(), and makes sure they do the right thing if a
hole in a directory is found by ext4_bread().
Some ext4_bread() callers did not need any changes either because they
already had its own hole detector paths.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_special_inode_operations have their own ifdef CONFIG_EXT4_FS_XATTR
to mask those methods. And ext4_iget also always sets it, so there is
an inconsistency.
Signed-off-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
Instead of checking whether the handle is valid, we check if journal
is enabled. This avoids taking the s_orphan_lock mutex in all cases
when there is no journal in use, including the error paths where
ext4_orphan_del() is called with a handle set to NULL.
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
htree_dirblock_to_tree() declares a non-initialized 'err' variable,
which is passed as a reference to another functions expecting them to
set this variable with their error codes.
It's passed to ext4_bread(), which then passes it to ext4_getblk(). If
ext4_map_blocks() returns 0 due to a lookup failure, leaving the
ext4_getblk() buffer_head uninitialized, it will make ext4_getblk()
return to ext4_bread() without initialize the 'err' variable, and
ext4_bread() will return to htree_dirblock_to_tree() with this variable
still uninitialized. htree_dirblock_to_tree() will pass this variable
with garbage back to ext4_htree_fill_tree(), which expects a number of
directory entries added to the rb-tree. which, in case, might return a
fake non-zero value due the garbage left in the 'err' variable, leading
the kernel to an Oops in ext4_dx_readdir(), once this is expecting a
filled rb-tree node, when in turn it will have a NULL-ed one, causing an
invalid page request when trying to get a fname struct from this NULL-ed
rb-tree node in this line:
fname = rb_entry(info->curr_node, struct fname, rb_hash);
The patch itself initializes the err variable in
htree_dirblock_to_tree() to avoid usage mistakes by the called
functions, and also fix ext4_getblk() to return a initialized 'err'
variable when ext4_map_blocks() fails a lookup.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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>
greatest note is a speed up for parallel, non-allocating DIO writes,
since we no longer take the i_mutex lock in that case. For bug fixes,
we fix an incorrect overhead calculation which caused slightly
incorrect results for df(1) and statfs(2). We also fixed bugs in the
metadata checksum feature.
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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:
"The usual collection of bug fixes and optimizations. Perhaps of
greatest note is a speed up for parallel, non-allocating DIO writes,
since we no longer take the i_mutex lock in that case.
For bug fixes, we fix an incorrect overhead calculation which caused
slightly incorrect results for df(1) and statfs(2). We also fixed
bugs in the metadata checksum feature."
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (23 commits)
ext4: undo ext4_calc_metadata_amount if we fail to claim space
ext4: don't let i_reserved_meta_blocks go negative
ext4: fix hole punch failure when depth is greater than 0
ext4: remove unnecessary argument from __ext4_handle_dirty_metadata()
ext4: weed out ext4_write_super
ext4: remove unnecessary superblock dirtying
ext4: convert last user of ext4_mark_super_dirty() to ext4_handle_dirty_super()
ext4: remove useless marking of superblock dirty
ext4: fix ext4 mismerge back in January
ext4: remove dynamic array size in ext4_chksum()
ext4: remove unused variable in ext4_update_super()
ext4: make quota as first class supported feature
ext4: don't take the i_mutex lock when doing DIO overwrites
ext4: add a new nolock flag in ext4_map_blocks
ext4: split ext4_file_write into buffered IO and direct IO
ext4: remove an unused statement in ext4_mb_get_buddy_page_lock()
ext4: fix out-of-date comments in extents.c
ext4: use s_csum_seed instead of i_csum_seed for xattr block
ext4: use proper csum calculation in ext4_rename
ext4: fix overhead calculation used by ext4_statfs()
...
The '__ext4_handle_dirty_metadata()' does not need the 'now' argument
anymore and we can kill it.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
