Return of the bi_rw tests is no longer bool after commit 74450be1. But
results of such tests are stored in bools. This doesn't fit in there
for some compilers (gcc 4.5 here), so either use !! magic to get real
bools or use ulong where the result is assigned somewhere.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
The open and release block_device_operations are currently
called with the BKL held. In order to change that, we must
first make sure that all drivers that currently rely
on this have no regressions.
This blindly pushes the BKL into all .open and .release
operations for all block drivers to prepare for the
next step. The drivers can subsequently replace the BKL
with their own locks or remove it completely when it can
be shown that it is not needed.
The functions blkdev_get and blkdev_put are the only
remaining users of the big kernel lock in the block
layer, besides a few uses in the ioctl code, none
of which need to serialize with blkdev_{get,put}.
Most of these two functions is also under the protection
of bdev->bd_mutex, including the actual calls to
->open and ->release, and the common code does not
access any global data structures that need the BKL.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Remove the current bio flags and reuse the request flags for the bio, too.
This allows to more easily trace the type of I/O from the filesystem
down to the block driver. There were two flags in the bio that were
missing in the requests: BIO_RW_UNPLUG and BIO_RW_AHEAD. Also I've
renamed two request flags that had a superflous RW in them.
Note that the flags are in bio.h despite having the REQ_ name - as
blkdev.h includes bio.h that is the only way to go for now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Now that the last user passing a NULL file pointer is gone we can remove
the redundant dentry argument and associated hacks inside vfs_fsynmc_range.
The next step will be removig the dentry argument from ->fsync, but given
the luck with the last round of method prototype changes I'd rather
defer this until after the main merge window.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Recent udev versions probe loop devices for filesystems meaning that
the /dev/disk hierarchy may contain useful entries such as
$ ls -l /dev/disk/by-label/Fedora-12-x86_64-Live
lrwxrwxrwx 1 root root 11 Mar 11 13:41 /dev/disk/by-label/Fedora-12-x86_64-Live -> ../../loop0
Unfortunately, no "change" uevent is generated when the loop device is
detached so the symlink persists. Additionally, no "change" uevent is
guaranteed to be generated when attaching an fd or changing capacity.
For example, user space could open the loop device O_RDONLY (in fact,
recent util-linux-ng does this) so udev's OPTIONS+="watch" machinery may
not trigger the "change" uevent.
This patch ensures that the "change" uevent is generated in all of
these cases. As a result, the /dev/disk hierarchy works as expected
for loop devices.
Signed-off-by: David Zeuthen <davidz@redhat.com>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (34 commits)
cfq-iosched: Fix the incorrect timeslice accounting with forced_dispatch
loop: Update mtime when writing using aops
block: expose the statistics in blkio.time and blkio.sectors for the root cgroup
backing-dev: Handle class_create() failure
Block: Fix block/elevator.c elevator_get() off-by-one error
drbd: lc_element_by_index() never returns NULL
cciss: unlock on error path
cfq-iosched: Do not merge queues of BE and IDLE classes
cfq-iosched: Add additional blktrace log messages in CFQ for easier debugging
i2o: Remove the dangerous kobj_to_i2o_device macro
block: remove 16 bytes of padding from struct request on 64bits
cfq-iosched: fix a kbuild regression
block: make CONFIG_BLK_CGROUP visible
Remove GENHD_FL_DRIVERFS
block: Export max number of segments and max segment size in sysfs
block: Finalize conversion of block limits functions
block: Fix overrun in lcm() and move it to lib
vfs: improve writeback_inodes_wb()
paride: fix off-by-one test
drbd: fix al-to-on-disk-bitmap for 4k logical_block_size
...
Update mtime when writing to backing filesystem using the address space
operations write_begin and write_end.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Get rid of any functions that test for these bits and make callers
use bio_rw_flagged() directly. Then it is at least directly apparent
what variable and flag they check.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If f_op->splice_read() is not implemented, fall back to a plain read.
Use vfs_readv() to read into previously allocated pages.
This will allow splice and functions using splice, such as the loop
device, to work on all filesystems. This includes "direct_io" files
in fuse which bypass the page cache.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Now that the bio list management stuff is generic, convert loop to use
bio lists instead of its own private bio list implementation.
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
mount/1865 is trying to release lock (&lo->lo_ctl_mutex) at:
but there are no more locks to release!
mutex is already unlocked in loop_clr_fd(), we should not
try to unlock it in lo_release() again.
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
With CONFIG_PROVE_LOCKING enabled
$ losetup /dev/loop0 file
$ losetup -o 32256 /dev/loop1 /dev/loop0
$ losetup -d /dev/loop1
$ losetup -d /dev/loop0
triggers a [ INFO: possible circular locking dependency detected ]
I think this warning is a false positive.
Open/close on a loop device acquires bd_mutex of the device before
acquiring lo_ctl_mutex of the same device. For ioctl(LOOP_CLR_FD) after
acquiring lo_ctl_mutex, fput on the backing_file might acquire the bd_mutex of
a device, if backing file is a device and this is the last reference to the
file being dropped . But it is guaranteed that it is impossible to have a
circular list of backing devices.(say loop2->loop1->loop0->loop2 is not
possible), which guarantees that this can never deadlock.
So this warning should be suppressed. It is very difficult to annotate lockdep
not to warn here in the correct way. A simple way to silence lockdep could be
to mark the lo_ctl_mutex in ioctl to be a sub class, but this might mask some
other real bugs.
@@ -1164,7 +1164,7 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode,
struct loop_device *lo = bdev->bd_disk->private_data;
int err;
- mutex_lock(&lo->lo_ctl_mutex);
+ mutex_lock_nested(&lo->lo_ctl_mutex, 1);
switch (cmd) {
case LOOP_SET_FD:
err = loop_set_fd(lo, mode, bdev, arg);
Or actually marking the bd_mutex after lo_ctl_mutex as a sub class could be
a better solution.
Luckily it is easy to avoid calling fput on backing file with lo_ctl_mutex
held, so no lockdep annotation is required.
If you do not like the special handling of the lo_ctl_mutex just for the
LOOP_CLR_FD ioctl in lo_ioctl(), the mutex handling could be moved inside
each of the individual ioctl handlers and I could send you another patch.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Honour barrier requests in the loop back block device driver.
In case of barrier bios, flush the backing file once before processing the
barrier and once after to guarantee ordering. In case of filesystems that
does not support fsync, barrier bios would be failed with -EOPNOTSUPP.
Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Upon a 'transfer error block' size is set to -EINVAL, but this becomes positive
since size is unsigned: p->offset still gets incremented.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
In loop_unplug() function is expected that mapping is set
and lo->lo_backing_file is not NULL.
Unfortunately loop_set_fd() set the request queue unplug function,
but loop_clr_fd() doesn't clear that.
Loop device allows open of non-configured loop in some situations.
If the unplug on request queue is called, loop module oopses because
of missing lo_backing_file.
Simple reproducer:
losetup /dev/loop0 /xxx
losetup -d /dev/loop0
dmsetup create x --table "0 1 linear /dev/loop0 0"
EIP is at loop_unplug+0x1d/0x3b
...
Call Trace:
blk_unplug+0x57/0x5e
dm_table_unplug_all+0x34/0x77 [dm_mod]
destroy_inode+0x27/0x38
generic_delete_inode+0xd5/0xd9
iput+0x4b/0x4e
dm_resume+0xca/0xfe [dm_mod]
dev_suspend+0x143/0x165 [dm_mod]
dm_ctl_ioctl+0x18e/0x1cf [dm_mod]
dev_suspend+0x0/0x165 [dm_mod]
dm_ctl_ioctl+0x0/0x1cf [dm_mod]
vfs_ioctl+0x22/0x69
do_vfs_ioctl+0x39d/0x3c7
trace_hardirqs_on+0xb/0xd
remove_vma+0x50/0x56
do_munmap+0x21c/0x237
sys_ioctl+0x2c/0x45
sysenter_do_call+0x12/0x31
Several reports here
http://www.kerneloops.org/search.php?search=loop_unplug
Fix it by simply clear unplug function together with
removing of backing file.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
When there are still queued bios and reference count
drops to zero, loop device must flush all queued bios.
Otherwise it can lead to situation that caller
closes the device, but some bios are still running
and endio() function call later OOpses when uses
unallocated mempool.
This happens for example when running dm-crypt over loop,
here is typical oops backtrace:
Oops: 0000 [#1] PREEMPT SMP
EIP is at mempool_free+0x12/0x6b
...
crypt_dec_pending+0x50/0x54 [dm_crypt]
crypt_endio+0x9f/0xa7 [dm_crypt]
crypt_endio+0x0/0xa7 [dm_crypt]
bio_endio+0x2b/0x2e
loop_thread+0x37a/0x3b1
do_lo_send_aops+0x0/0x165
autoremove_wake_function+0x0/0x33
loop_thread+0x0/0x3b1
kthread+0x3b/0x61
kthread+0x0/0x61
kernel_thread_helper+0x7/0x10
(But crash is reproducible with different dm targets
running over loop device too.)
Patch fixes it by flushing the bios in release call,
reusing the flush mechanism for switching backing store.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: James Morris <jmorris@namei.org>
Nothing uses prepare_write or commit_write. Remove them from the tree
completely.
[akpm@linux-foundation.org: schedule simple_prepare_write() for unexporting]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
