Eric has reported that since commit d2faa41516 "quota: Do not acquire
dqio_sem for dquot overwrites in v2 format" test generic/232
occasionally fails due to quota information being incorrect. Indeed that
commit was too eager to remove dqio_sem completely from the path that
just overwrites quota structure with updated information. Although that
is innocent on its own, another process that inserts new quota structure
to the same block can perform read-modify-write cycle of that block thus
effectively discarding quota information update if they race in a wrong
way.
Fix the problem by acquiring dqio_sem for reading for overwrites of
quota structure. Note that it *is* possible to completely avoid taking
dqio_sem in the overwrite path however that will require modifying path
inserting / deleting quota structures to avoid RMW cycles of the full
block and for now it is not clear whether it is worth the hassle.
Fixes: d2faa41516
Reported-and-tested-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Pull quota scaling updates from Jan Kara:
"This contains changes to make the quota subsystem more scalable.
Reportedly it improves number of files created per second on ext4
filesystem on fast storage by about a factor of 2x"
* 'quota_scaling' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (28 commits)
quota: Add lock annotations to struct members
quota: Reduce contention on dq_data_lock
fs: Provide __inode_get_bytes()
quota: Inline dquot_[re]claim_reserved_space() into callsite
quota: Inline inode_{incr,decr}_space() into callsites
quota: Inline functions into their callsites
ext4: Disable dirty list tracking of dquots when journalling quotas
quota: Allow disabling tracking of dirty dquots in a list
quota: Remove dq_wait_unused from dquot
quota: Move locking into clear_dquot_dirty()
quota: Do not dirty bad dquots
quota: Fix possible corruption of dqi_flags
quota: Propagate ->quota_read errors from v2_read_file_info()
quota: Fix error codes in v2_read_file_info()
quota: Push dqio_sem down to ->read_file_info()
quota: Push dqio_sem down to ->write_file_info()
quota: Push dqio_sem down to ->get_next_id()
quota: Push dqio_sem down to ->release_dqblk()
quota: Remove locking for writing to the old quota format
quota: Do not acquire dqio_sem for dquot overwrites in v2 format
...
Omit an extra message for a memory allocation failure in this function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Jan Kara <jack@suse.cz>
Currently we return -EIO on any error (or short read) from
->quota_read() while reading quota info. Propagate the error code
instead.
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
v2_read_file_info() returned -1 instead of proper error codes on error.
Luckily this is not easily visible from userspace as we have called
->check_quota_file shortly before and thus already verified the quota
file is sane. Still set the error codes to proper values.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Push down acquisition of dqio_sem into ->read_file_info() callback. This
is for consistency with other operations and it also allows us to get
rid of an ugliness in OCFS2.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Push down acquisition of dqio_sem into ->write_file_info() callback.
Mostly for consistency with other operations.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Push down acquisition of dqio_sem into ->get_next_id() callback. Mostly
for consistency with other operations.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Push down acquisition of dqio_sem into ->release_dqblk() callback. It
will allow quota formats to decide whether they need it or not.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
When dquot has space already allocated in a quota file, we just
overwrite that place when writing dquot. So we don't need any protection
against other modifications of quota file as these keep dquot in place.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Push down acquisition of dqio_sem into ->write_dqblk() callback. It will
allow quota formats to decide whether they need it or not.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Push down acquisition of dqio_sem into ->read_dqblk() callback. It will
allow quota formats to decide whether they need it or not.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Implement functions to get id of next existing quota structure in quota
file for quota tree based formats and thus for V2 quota format.
Signed-off-by: Jan Kara <jack@suse.cz>
The qtree_fmt_operations structures are never modified, so declare them as
const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Jan Kara <jack@suse.cz>
Currently quota format that supports 64-bit usage sets maximum quota
limit as 2^64-1. However quota core code uses signed numbers to track
usage and even limits themselves are stored in long long. Checking of
maximum allowable limits worked by luck until commit 14bf61ffe6
(quota: Switch ->get_dqblk() and ->set_dqblk() to use bytes as space
units) because variable we compared with was unsigned. After that commit
the type we compared against changed to signed and thus checks for
maximum limits with the newest VFS quota format started to refuse any
non-negative value. Later the problem was inadvertedly fixed by commit
b10a08194c (quota: Store maximum space limit in bytes) because we
started to compare against unsigned type as well.
Fix possible future problems of this kind by setting maximum limits to
2^63-1 to avoid overflow issues.
Reported-by: Carlos Carvalho <carlos@fisica.ufpr.br>
Signed-off-by: Jan Kara <jack@suse.cz>
Currently maximum space limit quota format supports is in blocks however
since we store space limits in bytes, this is somewhat confusing. So
store the maximum limit in bytes as well. Also rename the field to match
the new unit and related inode field to match the new naming scheme.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Currently, v2 quota format blindly stored flags from in-memory dqinfo on
disk, although there are no flags supported. Since it is stupid to store
flags which have no effect, just store 0 unconditionally and don't
bother loading it from disk.
Note that userspace could have stored some flags there via Q_SETINFO
quotactl and then later read them (although flags have no effect) but
I'm pretty sure noone does that (most definitely quota-tools don't and
quota interface doesn't have too much other users).
Signed-off-by: Jan Kara <jack@suse.cz>
Change struct dquot dq_id to a struct kqid and remove the now
unecessary dq_type.
Make minimal changes to dquot, quota_tree, quota_v1, quota_v2, ext3,
ext4, and ocfs2 to deal with the change in quota structures and
signatures. The ocfs2 changes are larger than most because of the
extensive tracing throughout the ocfs2 quota code that prints out
dq_id.
quota_tree.c:get_index is modified to take a struct kqid instead of a
qid_t because all of it's callers pass in dquot->dq_id and it allows
me to introduce only a single conversion.
The rest of the changes are either just replacing dq_type with dq_id.type,
adding conversions to deal with the change in type and occassionally
adding qid_eq to allow quota id comparisons in a user namespace safe way.
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Theodore Tso <tytso@mit.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
The current quota error message doesn't always print the disk name, so
it is hard to identify the "bad" disk when quota error happens.
This patch changes the standardized quota error message to print out disk name
and function name. It also uses a combination of cpp macro and inline function
to provide better type checking and to lower the text size of the message.
[Jan Kara: Export __quota_error]
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
This patch changes quota_tree.c:write_blk() to detect error caused by partial
write to quota file and add a macro to limit control printed quota error
messages so we won't fill up dmesg with a corrupted quota file.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
When we are asked for vfsv0 quota format and the file is in vfsv1
format (or vice versa), refuse to use the quota file. Also return
with error when we don't like the header of quota file.
Signed-off-by: Jan Kara <jack@suse.cz>
Fix warnings:
fs/quota/quota_v2.c: In function ‘v2_read_file_info’:
fs/quota/quota_v2.c:123: warning: integer constant is too large for ‘long’ type
fs/quota/quota_v2.c:124: warning: integer constant is too large for ‘long’ type
Reported-by: Jerry Leo <jerryleo860202@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
So far the maximum quota space limit was 4TB. Apparently this isn't enough
for Lustre guys anymore. So implement new quota format which raises block
limits to 2^64 bytes. Also store number of inodes and inode limits in
64-bit variables as 2^32 files isn't that insanely high anymore.
The first version of the patch has been developed by Andrew Perepechko
<Andrew.Perepechko@Sun.COM>.
CC: Andrew.Perepechko@Sun.COM
Signed-off-by: Jan Kara <jack@suse.cz>
Jan Kara