Ext4_da_write_end() used walk_page_buffers() with a callback function of
ext4_bh_unmapped_or_delay() to check if it extended the file size
without allocating any blocks (since in this case i_disksize needs to be
updated). However, this is didn't work proprely because the buffer head
has not been marked dirty yet --- this is done later in
block_commit_write() --- which caused ext4_bh_unmapped_or_delay() to
always return false.
In addition, walk_page_buffers() checks all of the buffer heads covering
the page, and the only buffer_head that should be checked is the one
covering the end of the write. Otherwise, given a 1k blocksize
filesystem and a 4k page size, the buffer head covering the first 1k
stripe of the file could be unmapped (because it was a sparse file), and
the second or third buffer_head covering that page could be mapped, and
using walk_page_buffers() would fail in this case since it would stop at
the first unmapped buffer_head and return true.
The core problem is that walk_page_buffers() was intended to do work in
a callback function, and a non-zero return value indicated a failure,
which termined the walk of the buffer heads covering the page. It was
not intended to be used with a boolean function, such as
ext4_bh_unmapped_or_delay().
Add addtional fix from Aneesh to protect i_disksize update rave with truncate.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
It can happen that buffers are removed from the page before it gets
marked dirty and then is passed to writepage(). In writepage() we just
initialize the buffers and check whether they are mapped and non
delay. If they are mapped and non delay we write the page. Otherwise we
mark them dirty. With this change we don't do block allocation at all
in ext4_*_write_page.
writepage() can get called under many condition and with a locking order
of journal_start -> lock_page, we should not try to allocate blocks in
writepage() which get called after taking page lock. writepage() can
get called via shrink_page_list even with a journal handle which was
created for doing inode update. For example when doing
ext4_da_write_begin we create a journal handle with credit 1 expecting a
i_disksize update for the inode. But ext4_da_write_begin can cause
shrink_page_list via _grab_page_cache. So having a valid handle via
ext4_journal_current_handle is not a guarantee that we can use the
handle for block allocation in writepage, since we shouldn't be using
credits that had been reserved for other updates. That it could result
in we running out of credits when we update inodes.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This provides a new ordered mode implementation which gets rid of using
buffer heads to enforce the ordering between metadata change with the
related data chage. Instead, in the new ordering mode, it keeps track
of all of the inodes touched by each transaction on a list, and when
that transaction is committed, it flushes all of the dirty pages for
those inodes. In addition, the new ordered mode reverses the lock
ordering of the page lock and transaction lock, which provides easier
support for delayed allocation.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
With the reverse locking, we need to start a transation before taking
the page lock, so in ext4_da_writepages() we need to break the write-out
into chunks, and restart the journal for each chunck to ensure the
write-out fits in a single transaction.
Updated patch from Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
which fixes delalloc sync hang with journal lock inversion, and address
the performance regression issue.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch does block reservation for delayed
allocation, to avoid ENOSPC later at page flush time.
Blocks(data and metadata) are reserved at da_write_begin()
time, the freeblocks counter is updated by then, and the number of
reserved blocks is store in per inode counter.
At the writepage time, the unused reserved meta blocks are returned
back. At unlink/truncate time, reserved blocks are properly released.
Updated fix from Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
to fix the oldallocator block reservation accounting with delalloc, added
lock to guard the counters and also fix the reservation for meta blocks.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Delayed allocation need to check free blocks at every write time.
percpu_counter_read_positive() is not quit accurate. delayed
allocation need a more accurate accounting, but using
percpu_counter_sum_positive() is frequently is quite expensive.
This patch added a new function to update center counter when sum
per-cpu counter, to increase the accurate rate for next
percpu_counter_read() and require less calling expensive
percpu_counter_sum().
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Updated with fixes from Mingming Cao <cmm@us.ibm.com> to unlock and
release the page from page cache if the delalloc write_begin failed, and
properly handle preallocated blocks. Also added a fix to clear
buffer_delay in block_write_full_page() after allocating a delayed
buffer.
Updated with fixes from Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
to update i_disksize properly and to add bmap support for delayed
allocation.
Updated with a fix from Valerie Clement <valerie.clement@bull.net> to
avoid filesystem corruption when the filesystem is mounted with the
delalloc option and blocksize < pagesize.
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Export mpage_bio_submit() and __mpage_writepage() for the benefit of
ext4's delayed allocation support. Also change __block_write_full_page
so that if buffers that have the BH_Delay flag set it will call
get_block() to get the physical block allocated, just as in the
!BH_Mapped case.
Signed-off-by: Alex Tomas <alex@clusterfs.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch makes ext4 use inode-based implementation of data=ordered mode
in JBD2. It allows us to unify some data=ordered and data=writeback paths
(especially writepage since we don't have to start a transaction anymore)
and remove some buffer walking.
Updated fix from Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
to fix file system hang due to corrupt jinode values.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch adds necessary framework into JBD2 to be able to track inodes
with each transaction and write-out their dirty data during transaction
commit time.
This new ordered mode brings all sorts of advantages such as possibility
to get rid of journal heads and buffer heads for data buffers in ordered
mode, better ordering of writes on transaction commit, simplification of
some JBD code, no more anonymous pages when truncate of data being
committed happens. Also with this new ordered mode, delayed allocation
on ordered mode is much simpler.
Signed-off-by: Jan Kara <jack@suse.cz>
We cannot call ext4_orphan_add() from under i_data_sem because that
causes a lock ordering violation between i_data_sem and and the
superblock lock.
Updated with Aneesh's locking order fix
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This changes are needed to support data=ordered mode handling via
inodes. This enables us to get rid of the journal heads and buffer
heads for data buffers in the ordered mode. With the changes, during
tranasaction commit we writeout the inode pages using the
writepages()/writepage(). That implies we take page lock during
transaction commit. This can cause a deadlock with the locking order
page_lock -> jbd2_journal_start, since the jbd2_journal_start can wait
for the journal_commit to happen and the journal_commit now needs to
take the page lock. To avoid this dead lock reverse the locking order.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
There's no need to call mark_inode_dirty() under page lock in
generic_write_end(). It unnecessarily makes hold time of page lock longer
and more importantly it forces locking order of page lock and transaction
start for journaling filesystems.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
We would like to get notified when we are doing a write on mmap section.
This is needed with respect to preallocated area. We split the preallocated
area into initialzed extent and uninitialzed extent in the call back. This
let us handle ENOSPC better. Otherwise we get ENOSPC in the writepage and
that would result in data loss. The changes are also needed to handle ENOSPC
when writing to an mmap section of files with holes.
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Update group infos when updating a group's descriptor.
Add group infos when adding a group's descriptor.
Refresh cache pages used by mb_alloc when changes occur.
This will probably need modifications when META_BG resizing will be allowed.
Signed-off-by: Frederic Bohe <frederic.bohe@bull.net>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Use the BUFFER_FNS functions (set_buffer_foo) to set buffer
head state atomically instead of nonatomic __set_bit().
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Set sbi->s_journal to NULL after we call journal_destroy(). This
will be later needed because after journal_destroy() is called,
ext4_clear_inode() can still be called for some inodes (e.g. root
inode) and we'll need to detect there that journal doesn't exists
anymore.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
mballoc allocation missed check for blocks reserved for root users. Add
ext4_has_free_blocks() check before allocation. Also modified
ext4_has_free_blocks() to support multiple block allocation request.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
To ensure that bits are truly on-disk after an fsync,
we should call blkdev_issue_flush if barriers are supported.
Inspired by an old thread on barriers, by reiserfs & xfs
which do the same, and by a patch SuSE ships with their kernel
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Move the code related to block allocation to a single function and add helper
funtions to differient allocation for data and meta data blocks
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When mballoc is enabled, block allocation for old block-based
files are allocated using mballoc allocator instead of old
block-based allocator. The old ext3 block reservation is turned
off when mballoc is turned on.
However, the in-core preallocation is not enabled for block-based/
non-extent based file block allocation. This result in performance
regression, as now we don't have "reservation" ore in-core preallocation
to prevent interleaved fragmentation in multiple writes workload.
This patch fix this by enable per inode in-core preallocation
for non extent files when mballoc is used.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When meta_bg feature is enabled and s_first_meta_bg != 0,
ext4_init_block_bitmap() miscalculates the number of block used by
the group descriptor table (0 or 1 for metablock block group)
This patch fixes this by using ext4_bg_num_gdb()
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Stephen Tweedie <sct@redhat.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Andreas Dilger <adilger@sun.com>
dx_root_limit() will had some dead code which forced it to always return
20, and dx_node_limit to always return 22 for debugging purposes.
Remove it.
Acked-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Fix ext4_ext_journal_restart() so it returns any errors reported by
ext4_journal_extend() and ext4_journal_restart().
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When pos=0 or depth, the fields of ext4_ext_path is are not
completely filled. This patch also removes some unnecessary code.
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
When allocating unitialized space at the end of file which had been
preallocated with the FALLOC_FL_KEEP_SIZE option, the file size is not
updated at that time. But the later we are not updating the file size
when writing to that preallocated space.
These changes are for code correctness. This patch allows us to update
the i_disksize at the write_end() callback of filesystem properly.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Quota allocation is not removed when ext4_mb_new_blocks calls
kmem_cache_alloc failed. Also make sure the allocation context is freed
on the error path.
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The previous sb_min_blocksize() has already set the block size.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
journal_try_to_free_buffers() could race with jbd commit transaction
when the later is holding the buffer reference while waiting for the
data buffer to flush to disk. If the caller of
journal_try_to_free_buffers() request tries hard to release the buffers,
it will treat the failure as error and return back to the caller. We
have seen the directo IO failed due to this race. Some of the caller of
releasepage() also expecting the buffer to be dropped when passed with
GFP_KERNEL mask to the releasepage()->journal_try_to_free_buffers().
With this patch, if the caller is passing the GFP_KERNEL to indicating
this call could wait, in case of try_to_free_buffers() failed, let's
waiting for journal_commit_transaction() to finish commit the current
committing transaction , then try to free those buffers again with
journal locked.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Reviewed-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch mostly controls the way inode are allocated in order to
make ialloc aware of flex_bg block group grouping. It achieves this
by bypassing the Orlov allocator when block group meta-data are packed
toghether through mke2fs. Since the impact on the block allocator is
minimal, this patch should have little or no effect on other block
allocation algorithms. By controlling the inode allocation, it can
basically control where the initial search for new block begins and
thus indirectly manipulate the block allocator.
This allocator favors data and meta-data locality so the disk will
gradually be filled from block group zero upward. This helps improve
performance by reducing seek time. Since the group of inode tables
within one flex_bg are treated as one giant inode table, uninitialized
block groups would not need to partially initialize as many inode
table as with Orlov which would help fsck time as the filesystem usage
goes up.
Signed-off-by: Jose R. Santos <jrs@us.ibm.com>
Signed-off-by: Valerie Clement <valerie.clement@bull.net>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Carlo Wood has demonstrated that it's possible to recover deleted
files from the journal. Something that will make this easier is if we
can put the time of the commit into commit block.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The error processing of the return value of mb_free_blocks is meanless
because it only returns 0. This fix includes
- make mb_free_blocks return void
- remove the error processing part in callers
- unlock group before calling ext4_error in mb_free_blocks
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When the directory fs/ext4 is not correctly created under proc, the entry
under this directory should not be created.
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_next_entry() is used by the debugging function dx_show_leaf(), so
it must be defined before that function.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Since this a non-static function, make it be ext4 specific to avoid
conflicts with potentially other filesystems.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
remove the definitions of macros XATTR_TRUSTED_PREFIX and XATTR_USER_PREFIX
since they are defined in linux/xattr.h
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_mb_seq_history_open(): check if sbi->s_mb_history is NULL
ext4_mb_history_init(): replace kmalloc and memset with kzalloc
ext4_mb_init_backend(): remove memset since kzalloc is used
ext4_mb_init(): the return value of ext4_mb_init_backend is int,
but i is unsigned, replace it with a new int variable.
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_mb_init_cache() incorrectly always return EIO on success. This
causes the caller of ext4_mb_init_cache() fail when it checks the return
value.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* remove unnecessary code in free_rb_tree_fname
* rename free_rb_tree_fname to ext4_htree_create_dir_info
since it and ext4_htree_free_dir_info are a pair
* replace kmalloc with kzalloc in ext4_htree_free_dir_info
All these make the code more readable and simple.
PS: this patch is also suitable for ext3.
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
if (...) BUG(); should be replaced with BUG_ON(...) when the test has no
side-effects to allow a definition of BUG_ON that drops the code completely.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@ disable unlikely @ expression E,f; @@
(
if (<... f(...) ...>) { BUG(); }
|
- if (unlikely(E)) { BUG(); }
+ BUG_ON(E);
)
@@ expression E,f; @@
(
if (<... f(...) ...>) { BUG(); }
|
- if (E) { BUG(); }
+ BUG_ON(E);
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
With mballoc we search for the best extent using different
criteria. We should always use the goal group when we are
starting with a new criteria.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Some architectures implement ext4_find_next_bit and
ext4_find_next_zero_bit in such a way that they return
greater than max for some input values. Make sure
mb_find_next_bit and mb_find_next_zero_bit return the
right values.
On 2.6.25 we have include/asm-x86/bitops_32.h
static inline unsigned find_first_bit(const unsigned long *addr, unsigned size)
{
unsigned x = 0;
while (x < size) {
unsigned long val = *addr++;
if (val)
return __ffs(val) + x;
x += (sizeof(*addr)<<3);
}
return x;
}
This can return value greater than size.
Reported and fixed here for lustre
https://bugzilla.lustre.org/show_bug.cgi?id=15932https://bugzilla.lustre.org/attachment.cgi?id=17205
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_dx_find_entry uses ext4_next_entry without verifying that the entry is
valid. If its rec_len == 0 this causes an infinite loop. Refactor the loop
to check the validity of entries before checking whether they match and
moving onto the next one.
There are other uses of ext4_next_entry in this file which also look
problematic. They should be reviewed and fixed if/when we have a test-case
that triggers them.
This patch fixes the first case (image hdb.25.softlockup.gz) reported in
http://bugzilla.kernel.org/show_bug.cgi?id=10882.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
While freeing indirect blocks we attach a journal head to the parent buffer
head, free the blocks, then journal the parent. If the indirect block list
is corrupted and points to the parent the journal head will be detached
when the block is cleared, causing an OOPS.
Check for that explicitly and handle it gracefully.
This patch fixes the third case (image hdb.20000057.nullderef.gz)
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If the orphan node list includes valid, untruncatable nodes with nlink > 0
the ext4_orphan_cleanup loop which attempts to delete them will not do so,
causing it to loop forever. Fix by checking for such nodes in the
ext4_orphan_get function.
This patch fixes the second case (image hdb.20000009.softlockup.gz)
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When we release the iclog, we do an atomic_dec_and_lock to determine if
we are the last reference and need to trigger update of log headers and
writeout. However, in xlog_state_get_iclog_space() we also need to
check if we have the last reference count there. If we do, we release
the log buffer, otherwise we decrement the reference count.
But the compare and decrement in xlog_state_get_iclog_space() is not
atomic, so both places can see a reference count of 2 and neither will
release the iclog. That leads to a filesystem hang.
Close the race by replacing the atomic_read() and atomic_dec() pair with
atomic_add_unless() to ensure that they are executed atomically.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Tim Shimmin <tes@sgi.com>
Tested-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix GFS2's need_sync()'s use of do_div() on an s64 by using div_s64() instead.
This does assume that gt_quota_scale_den can be cast to an s32.
This was introduced by patch b3b94faa5f.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Kernel Bugzilla #11063 points out that on some architectures (e.g. x86_32)
exec'ing an ELF without a PT_GNU_STACK program header should default to an
executable stack; but this got broken by the unlimited argv feature because
stack vma is now created before the right personality has been established:
so breaking old binaries using nested function trampolines.
Therefore re-evaluate VM_STACK_FLAGS in setup_arg_pages, where stack
vm_flags used to be set, before the mprotect_fixup. Checking through
our existing VM_flags, none would have changed since insert_vm_struct:
so this seems safer than finding a way through the personality labyrinth.
Reported-by: pageexec@freemail.hu
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The stack-glue merge changed the way we use flags in dlmglue in that we now
use the fs/dlm equivalents. Unfortunately, a merge error left the new flock
code only partially updated. This took a while to show up though, because
the lock level constants are actually identical between o2dlm and fs/dlm.
The *_CONVERT and *_NOQUEUE flags have different values though, which is
eventually causing a crash in flags_to_o2dlm().
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
The implementation of gfs2_inode_attr_in is removed.
So remove its declaration.
Signed-off-by: Li Xiaodong <lixd@cn.fujitsu.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The ability to mark files for direct i/o access when opened
normally is both unused and pointless, so this patch removes
support for that feature.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch removes the "recent list" which is used during allocation
and replaces it with the (already existing) mru list used during
deletion. The "recent list" was not a true mru list leading to a number
of inefficiencies including a "next" function which made scanning the
list an order N^2 operation wrt to the number of list elements.
This should increase allocation performance with large numbers of rgrps.
Its also a useful preparation and cleanup before some further changes
which are planned in this area.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The kernel's NFS client mount option parser currently doesn't allow
unrecognized or incorrect mount options. This prevents misspellings or
incorrectly specified mount options from possibly causing silent data
corruption.
However, NFS mount options are not standardized, so different operating
systems can use differently spelled mount options to support similar
features, or can support mount options which no other operating system
supports.
"Sloppy" mount option parsing, which allows the parser to ignore any
option it doesn't recognize, is needed to support automounters that often
use maps that are shared between heterogenous operating systems.
The legacy mount command ignores the validity of the values of mount
options entirely, except for the "sec=" and "proto=" options. If an
incorrect value is specified, the out-of-range value is passed to the
kernel; if a value is specified that contains non-numeric characters,
it appears as though the legacy mount command sets that option to zero
(probably incorrect behavior in general).
In any case, this sets a precedent which we will partially follow for
the kernel mount option parser:
+ if "sloppy" is not set, the parser will be strict about both
unrecognized options (same as legacy) and invalid option
values (stricter than legacy)
+ if "sloppy" is set, the parser will ignore unrecognized
options and invalid option values (same as legacy)
An "invalid" option value in this case means that either the type
(integer, short, or string) or sign (for integer values) of the specified
value is incorrect.
This patch does two things: it changes the NFS client's mount option
parsing loop so that it parses the whole string instead of failing at
the first unrecognized option or invalid option value. An unrecognized
option or an invalid option value cause the option to be skipped.
Then, the patch adds a "sloppy" mount option that allows the parsing
to succeed anyway if there were any problems during parsing. When
parsing a set of options is complete, if there are errors and "sloppy"
was specified, return success anyway. Otherwise, only return success
if there are no errors.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Set the default security flavor when we set the other mount option
default values for NFSv4. This cleans up the NFSv4 mount option parsing
path to look like the NFSv2/v3 one.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Set the default security flavor when we set the other mount option default
values. After this change, only the legacy user-space mount path needs to
set the NFS_MOUNT_SECFLAVOUR flag.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Refactor the NFS mount option parsing function to extract the
security flavor parsing logic into a separate function.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The remount path does not need to set the port in the server address.
Since it's not really a part of option parsing, move the nfs_set_port()
call to nfs_parse_mount_options()'s callers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move the UDP/TCP default timeo/retrans settings for text mounts to
nfs_init_timeout_values(), which was were they were always being
initialised (and sanity checked) for binary mounts.
Document the default timeout values using appropriate #defines.
Ensure that we initialise and sanity check the transport protocols that
may have been specified by the user.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Some server vendors support the higher versions of rpcbind only for
AF_INET6. The kernel doesn't need to use v3 or v4 for AF_INET anyway,
so change the kernel's rpcbind client to query AF_INET servers over
rpcbind v2 only.
This has a few interesting benefits:
1. If the rpcbind request is going over TCP, and the server doesn't
support rpcbind versions 3 or 4, the client reduces by two the number
of ephemeral ports left in TIME_WAIT for each rpcbind request. This
will help during NFS mount storms.
2. The rpcbind interaction with servers that don't support rpcbind
versions 3 or 4 will use less network traffic. Also helpful
during mount storms.
3. We can eliminate the kernel build option that controls whether the
kernel's rpcbind client uses rpcbind version 3 and 4 for AF_INET
servers. Less complicated kernel configuration...
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the nfsv4 callback thread is rapidly brought up and down, it's
possible that nfs_callback_svc might never get a chance to run. If
this happens, the cleanup at thread exit might never occur, throwing
the refcounting off and nfs_callback_info in an incorrect state.
Move the clean functions into nfs_callback_down. Also change the
nfs_callback_info struct to track the svc_rqst rather than svc_serv
since we need to know that to call svc_exit_thread.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The nfs_callback_mutex is sufficient protection.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
gcc (4.3.0) rightfully warns about this:
/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/fs/nfs/nfs4proc.c: In function nfs4_proc_setclientid_confirm:
/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/fs/nfs/nfs4proc.c:2936: warning: timeout may be used uninitialized in this function
nfs4_delay that's passed a pointer to 'timeout' is looking at its value
and sets it up to some value in the range: NFS4_POLL_RETRY_MIN..NFS4_POLL_RETRY_MAX
if (*timeout <= 0)
*timeout = NFS4_POLL_RETRY_MIN;
if (*timeout > NFS4_POLL_RETRY_MAX)
*timeout = NFS4_POLL_RETRY_MAX;
Therefore it will end up set to some sane, though rather indeterministic, value.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add support in the kernel NFS client's address parser for interface
identifiers.
IPv6 link-local addresses require an additional "interface identifier",
which is a network device name or an integer that indexes the array of
local network interfaces. They are suffixed to the address with a '%'.
For example:
fe80::215:c5ff:fe3b:e1b2%2
indicates an interface index of 2. Or
fe80::215:c5ff:fe3b:e1b2%eth0
indicates that requests should be routed through the eth0 device.
Without the interface ID, link-local addresses are not usable for NFS.
Both the kernel NFS client mount option parser and the mount.nfs command
can take either form. The mount.nfs command always passes the address
through getnameinfo(3), which usually re-writes interface indices as
device names.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
To make nfs_parse_server_address() more generally useful, allow it to
accept input strings that are not terminated with '\0'.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Traditionally the mount command has looked for a ":" to separate the
server's hostname from the export path in the mounted on device name,
like this:
mount server:/export /mounted/on/dir
The server's hostname is "server" and the export path is "/export".
You can also substitute a specific IPv4 network address for the server
hostname, like this:
mount 192.168.0.55:/export /mounted/on/dir
Raw IPv6 addresses present a problem, however, because they look
something like this:
fe80::200:5aff:fe00:30b
Note the use of colons.
To get around the presence of colons, copy the Solaris convention used for
mounting IPv6 servers by address: wrap a raw IPv6 address with square
brackets.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
To support passing a raw IPv6 address as a server hostname, we need to
expand the logic that handles splitting the passed-in device name into
a server hostname and export path
Start by pulling device name parsing out of the mount option validation
functions and into separate helper functions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix the 'nfs4_fs_type' undeclared error in nfs_remount when compiling sans
NFSv4...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Jeff Layton <jlayton@redhat.com>
Currently, if an unstable write completes, we cannot redirty the page in
order to reflect a new change in the page data until after we've sent a
COMMIT request.
This patch allows a page rewrite to proceed without the unnecessary COMMIT
step, putting it immediately back onto the dirty page list, undoing the
VM unstable write accounting, and removing the NFS_PAGE_TAG_COMMIT tag from
the NFS radix tree.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Simplify the loop in nfs_update_request by moving into a separate function
the code that attempts to update an existing cached NFS write.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: the "intr" and "nointr" mount options were recently retired.
Document this in the NFS mount option parser.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The kernel NFS mount option parser should ignore the retry= mount option
since it is meaningful only in user space. Today it expects a number
rather than arbitrary text, so it ignores the option if the value is
numeric, but chokes if there are other characters in the value.
Change it to allow any text (except ",") as its value.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We're not modifying the nfs_server when we call nfs_inc_server_stats and
friends, so allow the compiler to pass 'const' pointers too.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The fs/nfs/iostat.h header has definitions that were designed to be exposed
to user space. Move these definitions under include/linux so user space can
use the definitions in applications that read /proc/self/mountstats.
Also address a handful of coding style issues called out by checkpatch.pl in
fs/nfs/iostat.h.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
All instances are set to nfs_open(), so we should just remove the redundant
indirection. Ditto for the file_release op
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
ftruncate() access checking is supposed to be performed at open() time,
just like reads and writes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The cl_chatty flag alows us to control whether a given rpc client leaves
"server X not responding, timed out"
messages in the syslog. Such messages make sense for ordinary nfs
clients (where an unresponsive server means applications on the
mountpoint are probably hanging), but not for the callback client (which
can fail more commonly, with the only result just of disabling some
optimizations).
Previously cl_chatty was removed, do to lack of users; reinstate it, and
use it for the nfsd's callback client.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When remounting an NFS or NFS4 filesystem, the new NFS options are not
respected, yet the remount will still return success. This patch adds
a remount_fs sb op for NFS that checks any new nfs mount options against
the existing ones and fails the mount if any have changed.
This is only implemented for string-based mount options since doing
this with binary options isn't really feasible.
This is essentially the same as the original patch I sent out, but
adds a check to see if the addr= option has changed.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch removes a CVS keyword that wasn't updated for a long time
from a comment.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: fix a few dprintk messages that still need to show the RPC task ID
correctly, and be sure we use the preferred %lld or %llu instead of %Ld or
%Lu.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: some fops use NFSDBG_FILE, some use NFSDBG_VFS. Let's use
NFSDBG_FILE for all fops, and consistently report file names instead
of inode numbers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Recent work in fs/nfs/file.c neglected to add appropriate trace debugging
for the NFS client's address space operations.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Report the same debugging info and count function calls the
same for files and directories in nfs_opendir() and nfs_file_open().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Report the same debugging info in nfs_llseek_dir() and
nfs_llseek_file().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Report the same debugging info, count function calls the same,
and use similar function naming in nfs_fsync_dir() and nfs_fsync().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: refresh the help text for Kconfig items related to the NFS
client. Remove obsolete URLs, and make the language consistent among
the options.
Also move the ROOT_NFS config option next to the options related to the
NFS client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Revert commit 44dd151d "NFS: Don't mark a written page as uptodate until it
is on disk". While it is true that the write may fail, that is always the
case. There is no reason why we should treat data on pages that are not
already marked as PG_uptodate as being special. The only thing we gain is a
noticeable slowdown when re-reading these pages.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If a file is being extended, and we're creating a hole, we might as well
declare the entire page to be up to date.
This patch significantly improves the write performance for sparse files
in the case where lseek(SEEK_END) is used to append several non-contiguous
writes at intervals of < PAGE_SIZE.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv2 file locking currently fails the Connectathon tests, because the
calls to the VFS locking code do not return an EINVAL error if the
struct file_lock overflows the 32-bit boundaries.
The problem is due to the fact that we occasionally call helpers from
fs/locks.c in order to avoid RPC calls to the server when we know that a
local process holds the lock. These helpers are, of course, always
64-bit enabled, so EINVAL is not returned in cases when it would if
the call had gone to the NLM code.
For consistency, we therefore add support for a bounds-checking helper.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The commit 2785259631 (nfs: use GFP_NOFS
preloads for radix-tree insertion) appears to have introduced a bug:
We only want to call radix_tree_preload() once after creating a request.
Calling it every time we loop after we created the request, will cause
preemption count leaks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Nick Piggin <npiggin@suse.de>
* 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
SUNRPC: Fix an rpcbind breakage for the case of IPv6 lookups
SUNRPC: Fix a double-free in rpcbind
NFS: Fix readdir cache invalidation
With the removal of struct file from the xattr code,
reiserfs_file_release() isn't used anymore, so the prealloc isn't
discarded. This causes hangs later down the line.
This patch adds it to reiserfs_delete_inode. In most cases it will be a
no-op due to it already having been called, but will avoid hangs with
xattrs.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
invalidate_inode_pages2_range() takes page offset arguments, not byte
ranges.
Another thought is that individual pages might perhaps get evicted by VM
pressure, in which case we might perhaps want to re-read not only the
evicted page, but all subsequent pages too (in case the server returns
more/less data per page so that the alignment of the next entry
changes). We should therefore remove the condition that we only do this on
page->index==0.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I would suggest to remove the "experimental" status from Kdump.
Kdump is now in the kernel since a long time and used by Enterprise
distributions. I don't think that "experimental" is true any more.
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: vgoyal@redhat.com
Cc: kexec@lists.infradead.org
Cc: Bernhard Walle <bwalle@suse.de>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add information about the mapping state of the direct mapping to
/proc/meminfo. I chose /proc/meminfo because that is where all the other
memory statistics are too and it is a generally useful metric even
outside debugging situations. A lot of split kernel pages means the
kernel will run slower.
This way we can see how many large pages are really used for it and how
many are split.
Useful for general insight into the kernel.
v2: Add hotplug locking to 64bit to plug a very obscure theoretical race.
32bit doesn't need it because it doesn't support hotadd for lowmem.
Fix some typos
v3: Rename dpages_cnt
Add CONFIG ifdef for count update as requested by tglx
Expand description
v4: Fix stupid bugs added in v3
Move update_page_count to pageattr.c
Signed-off-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It's not immediately obvious from the code why we're doing this.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Benny Halevy <bhalevy@panasas.com>
Patch fixes a race that can result in an oops while adding a
lockres to the dlm lockres tracking list.
Bug introduced by mainline commit 29576f8bb5.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
We already allow local SH locks while we hold a cached EX glock, so here
we allow DF locks as well. This works only because we rely on the VFS's
invalidation for locally cached data, and because if we hold an EX lock,
then we know that no other node can be caching data relating to this
file.
It dramatically speeds up initial writes to O_DIRECT files since we fall
back to buffered I/O for this and would otherwise bounce between DF and
EX modes on each and every write call. The lessons to be learned from
that are to ensure that (for the time being anyway) O_DIRECT files are
preallocated and that they are written to using reasonably large I/O
sizes. Even so this change fixes that corner case nicely
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
There is a race in the delayed demote code where it does the wrong thing
if a demotion to UN has occurred for other reasons before the delay has
expired. This patch adds an assert to catch that condition as well as
fixing the root cause by adding an additional check for the UN state.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Fix some issues in pagemap_read noted by Alexey:
- initialize pagemap_walk.mm to "mm" , so the code starts working as
advertised
- initialize ->private to "&pm" so it wouldn't immediately oops in
pagemap_pte_hole()
- unstatic struct pagemap_walk, so two threads won't fsckup each other
(including those started by root, including flipping ->mm when you don't
have permissions)
- pagemap_read() contains two calls to ptrace_may_attach(), second one
looks unneeded.
- avoid possible kmalloc(0) and integer wraparound.
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Personally, I'd just remove the functionality entirely - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Don't use a static entry, so as to prevent races during concurrent use
of this function.
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In preparation for minorversion 1
All encoders now return an nfserr status (typically their
nfserr argument). Unsupported ops go through nfsd4_encode_operation
too, so use nfsd4_encode_noop to encode nothing for their reply body.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This commit includes a bugfix for the fragile setuid fixup code in the
case that filesystem capabilities are supported (in access()). The effect
of this fix is gated on filesystem capability support because changing
securebits is only supported when filesystem capabilities support is
configured.)
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Andrew G. Morgan <morgan@kernel.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The url in the help text for ntfs should be updated.
Acked-by: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The misc_mtx should provide all the protection required to keep the daemon
hash table sane during miscdev registration. Since this mutex is causing
gratuitous lockdep warnings, this patch removes it.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Reported-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When write in reiserfs_quota_write() fails, we have to properly release
i_mutex. One error path has been missing the unlock...
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When write in ext4_quota_write() fails, we have to properly release
i_mutex. One error path has been missing the unlock...
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When write in ext3_quota_write() fails, we have to properly release
i_mutex. One error path has been missing the unlock...
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a page was invalidated during splicing from file to a pipe, then
generic_file_splice_read() could return a short or zero count.
This manifested itself in rare I/O errors seen on nfs exported fuse
filesystems. This is because nfsd uses splice_direct_to_actor() to read
files, and fuse uses invalidate_inode_pages2() to invalidate stale data on
open.
Fix by redoing the page find/create if it was found to be truncated
(invalidated).
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
The legacy protocol's open operation doesn't handle an append operation
(it is expected that the client take care of it). We were incorrectly
passing the extended protocol's flag through even in legacy mode. This
was reported in bugzilla report #10689. This patch fixes the problem
by disallowing extended protocol open modes from being passed in legacy
mode and implemented append functionality on the client side by adding
a seek after the open.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
When devices are stacked, one device's merge_bvec_fn may need to perform
the mapping and then call one or more functions for its underlying devices.
The following bio fields are used:
bio->bi_sector
bio->bi_bdev
bio->bi_size
bio->bi_rw using bio_data_dir()
This patch creates a new struct bvec_merge_data holding a copy of those
fields to avoid having to change them directly in the struct bio when
going down the stack only to have to change them back again on the way
back up. (And then when the bio gets mapped for real, the whole
exercise gets repeated, but that's a problem for another day...)
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Some block devices support verifying the integrity of requests by way
of checksums or other protection information that is submitted along
with the I/O.
This patch implements support for generating and verifying integrity
metadata, as well as correctly merging, splitting and cloning bios and
requests that have this extra information attached.
See Documentation/block/data-integrity.txt for more information.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Move struct bio_set and biovec_slab definitions to bio.h so they can
be used outside of bio.c.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
GFS2 calls permission() to verify permissions after locks on the files
have been taken.
For this it's sufficient to call gfs2_permission() instead. This
results in the following changes:
- IS_RDONLY() check is not performed
- IS_IMMUTABLE() check is not performed
- devcgroup_inode_permission() is not called
- security_inode_permission() is not called
IS_RDONLY() should be unnecessary anyway, as the per-mount read-only
flag should provide protection against read-only remounts during
operations. do_gfs2_set_flags() has been fixed to perform
mnt_want_write()/mnt_drop_write() to protect against remounting
read-only.
IS_IMMUTABLE has been added to gfs2_permission()
Repeating the security checks seems to be pointless, as they don't
normally change, and if they do, it's independent of the filesystem
state.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
lock_kernel() calls have been pushed down into code which needs it, so
there is no need to take the BKL at this level anymore.
This work inspired and aided by Andi Kleen's unlocked_fasync() patches.
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
- Replace remote_llseek with generic_file_llseek_unlocked (to force compilation
failures in all users)
- Change all users to either use generic_file_llseek_unlocked directly or
take the BKL around. I changed the file systems who don't use the BKL
for anything (CIFS, GFS) to call it directly. NCPFS and SMBFS and NFS
take the BKL, but explicitely in their own source now.
I moved them all over in a single patch to avoid unbisectable sections.
Open problem: 32bit kernels can corrupt fpos because its modification
is not atomic, but they can do that anyways because there's other paths who
modify it without BKL.
Do we need a special lock for the pos/f_version = 0 checks?
Trond says the NFS BKL is likely not needed, but keep it for now
until his full audit.
v2: Use generic_file_llseek_unlocked instead of remote_llseek_unlocked
and factor duplicated code (suggested by hch)
Cc: Trond.Myklebust@netapp.com
Cc: swhiteho@redhat.com
Cc: sfrench@samba.org
Cc: vandrove@vc.cvut.cz
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The FAT BKL removal patch can cause deadlocks. It turns out that the new
lock_super() calls are unneeded, remove them (as directed by Linus).
Reported-by: "Tony Luck" <tony.luck@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Have separate vectors of operation decoders for each minorversion.
Obsolete ops in newer minorversions have default implementation returning
nfserr_opnotsupp.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Check minorversion once before decoding any operation and reject with
nfserr_minor_vers_mismatch if != 0 (this still happens in nfsd4_proc_compound).
In this case return a zero length resultdata array as required by RFC3530.
minorversion 1 processing will have its own vector of decoders.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Multiple mnt_want_write() calls in the switch statement looks really
ugly.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fsync_buffers_list() and sync_dirty_buffer() both issue async writes and
then immediately wait on them. Conceptually, that makes them sync writes
and we should treat them as such so that the IO schedulers can handle
them appropriately.
This patch fixes a write starvation issue that Lin Ming reported, where
xx is stuck for more than 2 minutes because of a large number of
synchronous IO in the system:
INFO: task kjournald:20558 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
kjournald D ffff810010820978 6712 20558 2
ffff81022ddb1d10 0000000000000046 ffff81022e7baa10 ffffffff803ba6f2
ffff81022ecd0000 ffff8101e6dc9160 ffff81022ecd0348 000000008048b6cb
0000000000000086 ffff81022c4e8d30 0000000000000000 ffffffff80247537
Call Trace:
[<ffffffff803ba6f2>] kobject_get+0x12/0x17
[<ffffffff80247537>] getnstimeofday+0x2f/0x83
[<ffffffff8029c1ac>] sync_buffer+0x0/0x3f
[<ffffffff8066d195>] io_schedule+0x5d/0x9f
[<ffffffff8029c1e7>] sync_buffer+0x3b/0x3f
[<ffffffff8066d3f0>] __wait_on_bit+0x40/0x6f
[<ffffffff8029c1ac>] sync_buffer+0x0/0x3f
[<ffffffff8066d48b>] out_of_line_wait_on_bit+0x6c/0x78
[<ffffffff80243909>] wake_bit_function+0x0/0x23
[<ffffffff8029e3ad>] sync_dirty_buffer+0x98/0xcb
[<ffffffff8030056b>] journal_commit_transaction+0x97d/0xcb6
[<ffffffff8023a676>] lock_timer_base+0x26/0x4b
[<ffffffff8030300a>] kjournald+0xc1/0x1fb
[<ffffffff802438db>] autoremove_wake_function+0x0/0x2e
[<ffffffff80302f49>] kjournald+0x0/0x1fb
[<ffffffff802437bb>] kthread+0x47/0x74
[<ffffffff8022de51>] schedule_tail+0x28/0x5d
[<ffffffff8020cac8>] child_rip+0xa/0x12
[<ffffffff80243774>] kthread+0x0/0x74
[<ffffffff8020cabe>] child_rip+0x0/0x12
Lin Ming confirms that this patch fixes the issue. I've run tests with
it for the past week and no ill effects have been observed, so I'm
proposing it for inclusion into 2.6.26.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
knfsd currently uses 2 signal masks when processing requests. A "loose"
mask (SHUTDOWN_SIGS) that it uses when receiving network requests, and
then a more "strict" mask (ALLOWED_SIGS, which is just SIGKILL) that it
allows when doing the actual operation on the local storage.
This is apparently unnecessarily complicated. The underlying filesystem
should be able to sanely handle a signal in the middle of an operation.
This patch removes the signal mask handling from knfsd altogether. When
knfsd is started as a kthread, all signals are ignored. It then allows
all of the signals in SHUTDOWN_SIGS. There's no need to set the mask
as well.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Thanks to Frank Van Maarseveen for the original problem report: "A
privileged process on an NFS client which drops privileges after using
them to change the current working directory, will experience incorrect
EACCES after an NFS server reboot. This problem can also occur after
memory pressure on the server, particularly when the client side is
quiet for some time."
This occurs because the filehandle points to a directory whose parents
are no longer in the dentry cache, and we're attempting to reconnect the
directory to its parents without adequate permissions to perform lookups
in the parent directories.
We can therefore fix the problem by acquiring the necessary capabilities
before attempting the reconnection. We do this only in the
no_subtree_check case, since the documented behavior of the
subtree_check export option requires the server to check that the user
has lookup permissions on all parents.
The subtree_check case still has a problem, since reconnect_path()
unnecessarily requires both read and lookup permissions on all parent
directories. However, a fix in that case would be more delicate, and
use of subtree_check is already discouraged for other reasons.
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Frank van Maarseveen <frankvm@frankvm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
I discovered that we had a list onto which every lock_dlm
lock was being put. Its only function was to discover whether
we'd got any locks left after umount. Since there was already
a counter for that purpose as well, I removed the list. The
saving is sizeof(struct list_head) per glock - well worth
having.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
There are several reasons why this is undesirable:
1. It never happens during normal operation anyway
2. If it does happen it causes performance to be very, very poor
3. It isn't likely to solve the original problem (memory shortage
on remote DLM node) it was supposed to solve
4. It uses a bunch of arbitrary constants which are unlikely to be
correct for any particular situation and for which the tuning seems
to be a black art.
5. In an N node cluster, only 1/N of the dropped locked will actually
contribute to solving the problem on average.
So all in all we are better off without it. This also makes merging
the lock_dlm module into GFS2 a bit easier.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes Red Hat bugzilla bug 450156.
This started with a not-too-improbable mount failure because the
locking protocol was never set back to its proper "lock_dlm" after the
system was rebooted in the middle of a gfs2_fsck. That left a
(purposely) invalid locking protocol in the superblock, which caused an
error when the file system was mounted the next time.
When there's an error mounting, vfs calls DQUOT_OFF, which calls
vfs_quota_off which calls gfs2_sync_fs. Next, gfs2_sync_fs calls
gfs2_log_flush passing s_fs_info. But due to the error, s_fs_info
had been previously set to NULL, and so we have the kernel oops.
My solution in this patch is to test for the NULL value before passing
it. I tested this patch and it fixes the problem.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The previous attempt to fix the locking in readpage failed due
to the use of a "try lock" which resulted in occasional high
cpu usage during testing (due to repeated tries) and also it
did not resolve all the ordering problems wrt the transaction
lock (although it did solve all the inode lock ordering problems).
This patch avoids the problem by unlocking the page and getting the
locks in the correct order. This means that we have to retest the
page to ensure that it hasn't changed when we relock the page.
This now passes the tests which were previously failing.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The patch to remove lock_nolock managed to get the arguments
of this list_add backwards. This fixes it.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch merges the lock_nolock module into GFS2 itself. As well as removing
some of the overhead of the module, it also means that its now impossible to
build GFS2 without a lock module (which would be a pointless thing to do
anyway).
We also plan to merge lock_dlm into GFS2 in the future, but that is a more
tricky task, and will therefore be a separate patch.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: David Teigland <teigland@redhat.com>
This looks like a lot of change, but in fact its not. Mostly its
things moving from one file to another. The change is just that
instead of queuing lock completions and callbacks from the DLM
we now pass them directly to GFS2.
This gives us a net loss of two list heads per glock (a fair
saving in memory) plus a reduction in the latency of delivering
the messages to GFS2, plus we now have one thread fewer as well.
There was a bug where callbacks and completions could be delivered
in the wrong order due to this unnecessary queuing which is fixed
by this patch.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>
This patch implements a number of cleanups to the core of the
GFS2 glock code. As a result a lot of code is removed. It looks
like a really big change, but actually a large part of this patch
is either removing or moving existing code.
There are some new bits too though, such as the new run_queue()
function which is considerably streamlined. Highlights of this
patch include:
o Fixes a cluster coherency bug during SH -> EX lock conversions
o Removes the "glmutex" code in favour of a single bit lock
o Removes the ->go_xmote_bh() for inodes since it was duplicating
->go_lock()
o We now only use the ->lm_lock() function for both locks and
unlocks (i.e. unlock is a lock with target mode LM_ST_UNLOCKED)
o The fast path is considerably shortly, giving performance gains
especially with lock_nolock
o The glock_workqueue is now used for all the callbacks from the DLM
which allows us to simplify the lock_dlm module (see following patch)
o The way is now open to make further changes such as eliminating the two
threads (gfs2_glockd and gfs2_scand) in favour of a more efficient
scheme.
This patch has undergone extensive testing with various test suites
so it should be pretty stable by now.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>
It's not even passed on to smp_call_function() anymore, since that
was removed. So kill it.
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch fixes bz 450641.
This patch changes the computation for zero_metapath_length(), which it
renames to metapath_branch_start(). When you are extending the metadata
tree, The indirect blocks that point to the new data block must either
diverge from the existing tree either at the inode, or at the first
indirect block. They can diverge at the first indirect block because the
inode has room for 483 pointers while the indirect blocks have room for
509 pointers, so when the tree is grown, there is some free space in the
first indirect block. What metapath_branch_start() now computes is the
height where the first indirect block for the new data block is located.
It can either be 1 (if the indirect block diverges from the inode) or 2
(if it diverges from the first indirect block).
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch fixes bugzilla bug bz448866: gfs2: BUG: unable to
handle kernel paging request at ffff81002690e000.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
In some cases it could happen that some block passed test in
udf_check_anchor_block() even though udf_read_tagged() refused to read it later
(e.g. because checksum was not correct). This patch makes
udf_check_anchor_block() use udf_read_tagged() so that the checking is
stricter.
This fixes the regression (certain disks unmountable) caused by commit
423cf6dc04.
Signed-off-by: Tomas Janousek <tomi@nomi.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Fix a sign issue in xdr_decode_fhstatus3()
Fix incorrect comparison in nfs_validate_mount_data()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix the following sparse warnings:
fs/dcache.c:2183:19: warning: symbol 'filp_cachep' was not declared. Should it be static?
fs/dcache.c:115:3: warning: context imbalance in 'dentry_iput' - unexpected unlock
fs/dcache.c:188:2: warning: context imbalance in 'dput' - different lock contexts for basic block
fs/dcache.c:400:2: warning: context imbalance in 'prune_one_dentry' - different lock contexts for basic block
fs/dcache.c:431:22: warning: context imbalance in 'prune_dcache' - different lock contexts for basic block
fs/dcache.c:563:2: warning: context imbalance in 'shrink_dcache_sb' - different lock contexts for basic block
fs/dcache.c:1385:6: warning: context imbalance in 'd_delete' - wrong count at exit
fs/dcache.c:1636:2: warning: context imbalance in '__d_unalias' - unexpected unlock
fs/dcache.c:1735:2: warning: context imbalance in 'd_materialise_unique' - different lock contexts for basic block
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The path that __d_path() computes can become slightly inconsistent when it
races with mount operations: it grabs the vfsmount_lock when traversing mount
points but immediately drops it again, only to re-grab it when it reaches the
next mount point. The result is that the filename computed is not always
consisent, and the file may never have had that name. (This is unlikely, but
still possible.)
Fix this by grabbing the vfsmount_lock for the whole duration of
__d_path().
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: John Johansen <jjohansen@suse.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Rename nfsd_permission() specific MAY_* flags to NFSD_MAY_* to make it
clear, that these are not used outside nfsd, and to avoid name and
number space conflicts with the VFS.
[comment from hch: rename MAY_READ, MAY_WRITE and MAY_EXEC as well]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
OCFS2 can return -ERESTARTSYS from write requests (and possibly
elsewhere) if there is a signal pending.
If nfsd is shutdown (by sending a signal to each thread) while there
is still an IO load from the client, each thread could handle one last
request with a signal pending. This can result in -ERESTARTSYS
which is not understood by nfserrno() and so is reflected back to
the client as nfserr_io aka -EIO. This is wrong.
Instead, interpret ERESTARTSYS to mean "try again later" by returning
nfserr_jukebox. The client will resend and - if the server is
restarted - the write will (hopefully) be successful and everyone will
be happy.
The symptom that I narrowed down to this was:
copy a large file via NFS to an OCFS2 filesystem, and restart
the nfs server during the copy.
The 'cp' might get an -EIO, and the file will be corrupted -
presumably holes in the middle where writes appeared to fail.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We need the nfsd_mutex before accessing nfsd_serv->sv_nrthreads or we
can't even guarantee nfsd_serv will still be there.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
If lockd_down is called very rapidly after lockd_up returns, then
there is a slim chance that lockd() will never be called. kthread()
will return before calling the function, so we'll end up never
actually calling the cleanup functions for the thread.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Since we no longer make any distinction between shutdown signals with
nfsd, then it becomes easier to just standardize on a particular signal
to use to bring it down (SIGINT, in this case).
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch is rather large, but I couldn't figure out a way to break it
up that would remain bisectable. It does several things:
- change svc_thread_fn typedef to better match what kthread_create expects
- change svc_pool_map_set_cpumask to be more kthread friendly. Make it
take a task arg and and get rid of the "oldmask"
- have svc_set_num_threads call kthread_create directly
- eliminate __svc_create_thread
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The special handling for SIGHUP in knfsd is a holdover from much
earlier versions of Linux where reloading the export table was
more expensive. That facility is not really needed anymore and
to my knowledge, is seldom-used.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Several of the nfsd filesystem interfaces allow changes to parameters
that don't have any effect on a running nfsd service. They are only ever
checked when nfsd is started. This patch fixes it so that changes to
those procfiles return -EBUSY if nfsd is already running to make it
clear that changes on the fly don't work.
The patch should also close some relatively harmless races between
changing the info in those interfaces and starting nfsd, since these
variables are being moved under the protection of the nfsd_mutex.
Finally, the nfsv4recoverydir file always returns -EINVAL if read. This
patch fixes it to return the recoverydir path as expected.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This removes the BKL from the RPC service creation codepath. The BKL
really isn't adequate for this job since some of this info needs
protection across sleeps.
Also, add some comments to try and clarify how the locking should work
and to make it clear that the BKL isn't necessary as long as there is
adequate locking between tasks when touching the svc_serv fields.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
WRITEMEM zeroes the last word in the destination buffer
for padding purposes, but this must not be done if
no bytes are to be copied, as it would result
in zeroing of the word right before the array.
The current implementation works since it's always called
with non zero nbytes or it follows an encoding of the
string (or opaque) length which, if equal to zero,
can be overwritten with zero.
Nevertheless, it seems safer to check for this case.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We already print each operation of the compound when debugging is turned
on; printing the result could also help with remote debugging.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fl_insert and fl_remove are not used right now in the kernel. Remove them.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
generic_readlink calls ERR_PTR for negative and positive values
(vfs_readlink returns length of "link"), but it should not
(not an errno) and does not need to.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Here are some more places where path_{get,put}() can be used instead of
dput()/mntput() pair.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The POSIX.1 draft spec for futimens()/utimensat() says:
Only a process with the effective user ID equal to the
user ID of the file, *or with write access to the file*,
or with appropriate privileges may use futimens() or
utimensat() with a null pointer as the times argument
or with both tv_nsec fields set to the special value
UTIME_NOW.
The important piece here is "with write access to the file", and
this matters for futimens(), which deals with an argument that
is a file descriptor referring to the file whose timestamps are
being updated, The standard is saying that the "writability"
check is based on the file permissions, not the access mode with
which the file is opened. (This behavior is consistent with the
semantics of FreeBSD's futimes().) However, Linux is currently
doing the latter -- futimens(fd, times) is a library
function implemented as
utimensat(fd, NULL, times, 0)
and within the utimensat() implementation we have the code:
f = fget(dfd); // dfd is 'fd'
...
if (f) {
if (!(f->f_mode & FMODE_WRITE))
goto mnt_drop_write_and_out;
The check should instead be based on the file permissions.
Thanks to Miklos for pointing out how to do this check.
Miklos also pointed out a simplification that could be
made to my first version of this patch, since the checks
for the pathname and file descriptor cases can now be
conflated.
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The POSIX.1 draft spec for utimensat() says:
Only a process with the effective user ID equal to the
user ID of the file or with appropriate privileges may use
futimens() or utimensat() with a non-null times argument
that does not have both tv_nsec fields set to UTIME_NOW
and does not have both tv_nsec fields set to UTIME_OMIT.
If this condition is violated, then the error EPERM should result.
However, the current implementation does not generate EPERM if
one tv_nsec field is UTIME_NOW while the other is UTIME_OMIT.
It should give this error for that case.
This patch:
a) Repairs that problem.
b) Removes the now unneeded nsec_special() helper function.
c) Adds some comments to explain the checks that are being
performed.
Thanks to Miklos, who provided comments on the previous iteration
of this patch. As a result, this version is a little simpler and
and its logic is better structured.
Miklos suggested an alternative idea, migrating the
is_owner_or_cap() checks into fs/attr.c:inode_change_ok() via
the use of an ATTR_OWNER_CHECK flag. Maybe we could do that
later, but for now I've gone with this version, which is
IMO simpler, and can be more easily read as being correct.
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The POSIX.1 draft spec for utimensat() says that if a times[n].tv_nsec
field is UTIME_OMIT or UTIME_NOW, then the value in the corresponding
tv_sec field is ignored. See the last sentence of this para, from
the spec:
If the tv_nsec field of a timespec structure has
the special value UTIME_NOW, the file's relevant
timestamp shall be set to the greatest value
supported by the file system that is not greater than
the current time. If the tv_nsec field has the
special value UTIME_OMIT, the file's relevant
timestamp shall not be changed. In either case,
the tv_sec field shall be ignored.
However the current Linux implementation requires the tv_sec value to be
zero (or the EINVAL error results). This requirement should be removed.
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch fixes utimensat() to make its behavior consistent
with that of utime()/utimes() when dealing with files marked
immutable and append-only.
The current utimensat() implementation also returns EPERM if
'times' is non-NULL and the tv_nsec fields are both UTIME_NOW.
For consistency, the
(times != NULL && times[0].tv_nsec == UTIME_NOW &&
times[1].tv_nsec == UTIME_NOW)
case should be treated like the traditional utimes() case where
'times' is NULL. That is, the call should succeed for a file
marked append-only and should give the error EACCES if the file
is marked as immutable.
The simple way to do this is to set 'times' to NULL
if (times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW).
This is also the natural approach, since POSIX.1 semantics consider the
times == {{x, UTIME_NOW}, {y, UTIME_NOW}}
to be exactly equivalent to the case for
times == NULL.
(Thanks to Miklos for pointing this out.)
Patch 3 in this series relies on the simplification provided
by this patch.
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
devcgroup_inode_permission() expects MAY_FOO, not FMODE_FOO; kindly
keep your misdesign consistent if you positively have to inflict it
on the kernel.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Christian Borntraeger reported that reinstating cond_resched() with
CONFIG_PREEMPT caused a performance regression on lmbench:
For example select file 500:
23 microseconds
32 microseconds
and that's really because we totally unnecessarily do the cond_resched()
in the innermost loop of select(), which is just silly.
This moves it out from the innermost loop (which only ever loops ove the
bits in a single "unsigned long" anyway), which makes the performance
regression go away.
Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This replaces the use of the BKL in the FAT family of filesystems with the
existing superblock lock instead.
The code already appears to do mostly proper locking with its own private
spinlocks (and mutexes), but while the BKL could possibly have been
dropped entirely, converting it to use the superblock lock (which is just
a regular mutex) is the conservative thing to do.
As a per-filesystem mutex, it not only won't have any of the possible
latency issues related to the BKL, but the lock is obviously private to
the particular filesystem instance and will thus not cause problems for
entirely unrelated users like the BKL can.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
All in-kernel char device open() functions now either have their own
lock_kernel() calls or clearly do not need one.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
I stared at this code for a while and almost deleted it before
understanding crept into my slow brain. Hopefully this makes life easier
for the next person to happen on it.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
