Commit Graph

96 Commits

Author SHA1 Message Date
Namhyung Kim
ac04fee0b5 loop: export module parameters
Export 'max_loop' and 'max_part' parameters to sysfs so user can know
that how many devices are allowed and how many partitions are supported.

If 'max_loop' is 0, there is no restriction on the number of loop devices.
User can create/use the devices as many as minor numbers available. If
'max_part' is 0, it means simply the device doesn't support partitioning.

Also note that 'max_part' can be adjusted to power of 2 minus 1 form if
needed. User should check this value after the module loading if he/she
want to use that number correctly (i.e. fdisk, mknod, etc.).

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-27 07:59:25 +02:00
Namhyung Kim
a1c15c59fe loop: handle on-demand devices correctly
When finding or allocating a loop device, loop_probe() did not take
partition numbers into account so that it can result to a different
device. Consider following example:

$ sudo modprobe loop max_part=15
$ ls -l /dev/loop*
brw-rw---- 1 root disk 7,   0 2011-05-24 22:16 /dev/loop0
brw-rw---- 1 root disk 7,  16 2011-05-24 22:16 /dev/loop1
brw-rw---- 1 root disk 7,  32 2011-05-24 22:16 /dev/loop2
brw-rw---- 1 root disk 7,  48 2011-05-24 22:16 /dev/loop3
brw-rw---- 1 root disk 7,  64 2011-05-24 22:16 /dev/loop4
brw-rw---- 1 root disk 7,  80 2011-05-24 22:16 /dev/loop5
brw-rw---- 1 root disk 7,  96 2011-05-24 22:16 /dev/loop6
brw-rw---- 1 root disk 7, 112 2011-05-24 22:16 /dev/loop7
$ sudo mknod /dev/loop8 b 7 128
$ sudo losetup /dev/loop8 ~/temp/disk-with-3-parts.img
$ sudo losetup -a
/dev/loop128: [0805]:278201 (/home/namhyung/temp/disk-with-3-parts.img)
$ ls -l /dev/loop*
brw-rw---- 1 root disk 7,    0 2011-05-24 22:16 /dev/loop0
brw-rw---- 1 root disk 7,   16 2011-05-24 22:16 /dev/loop1
brw-rw---- 1 root disk 7, 2048 2011-05-24 22:18 /dev/loop128
brw-rw---- 1 root disk 7, 2049 2011-05-24 22:18 /dev/loop128p1
brw-rw---- 1 root disk 7, 2050 2011-05-24 22:18 /dev/loop128p2
brw-rw---- 1 root disk 7, 2051 2011-05-24 22:18 /dev/loop128p3
brw-rw---- 1 root disk 7,   32 2011-05-24 22:16 /dev/loop2
brw-rw---- 1 root disk 7,   48 2011-05-24 22:16 /dev/loop3
brw-rw---- 1 root disk 7,   64 2011-05-24 22:16 /dev/loop4
brw-rw---- 1 root disk 7,   80 2011-05-24 22:16 /dev/loop5
brw-rw---- 1 root disk 7,   96 2011-05-24 22:16 /dev/loop6
brw-rw---- 1 root disk 7,  112 2011-05-24 22:16 /dev/loop7
brw-r--r-- 1 root root 7,  128 2011-05-24 22:17 /dev/loop8

After this patch, /dev/loop8 - instead of /dev/loop128 - was
accessed correctly.

In addition, 'range' passed to blk_register_region() should
include all range of dev_t that LOOP_MAJOR can address. It does
not need to be limited by partition numbers unless 'max_loop'
param was specified.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-24 16:48:55 +02:00
Namhyung Kim
78f4bb367f loop: limit 'max_part' module param to DISK_MAX_PARTS
The 'max_part' parameter controls the number of maximum partition
a loop block device can have. However if a user specifies very
large value it would exceed the limitation of device minor number
and can cause a kernel panic (or, at least, produce invalid
device nodes in some cases).

On my desktop system, following command kills the kernel. On qemu,
it triggers similar oops but the kernel was alive:

$ sudo modprobe loop max_part0000
 ------------[ cut here ]------------
 kernel BUG at /media/Linux_Data/project/linux/fs/sysfs/group.c:65!
 invalid opcode: 0000 [#1] SMP
 last sysfs file:
 CPU 0
 Modules linked in: loop(+)

 Pid: 43, comm: insmod Tainted: G        W   2.6.39-qemu+ #155 Bochs Bochs
 RIP: 0010:[<ffffffff8113ce61>]  [<ffffffff8113ce61>] internal_create_group=
+0x2a/0x170
 RSP: 0018:ffff880007b3fde8  EFLAGS: 00000246
 RAX: 00000000ffffffef RBX: ffff880007b3d878 RCX: 00000000000007b4
 RDX: ffffffff8152da50 RSI: 0000000000000000 RDI: ffff880007b3d878
 RBP: ffff880007b3fe38 R08: ffff880007b3fde8 R09: 0000000000000000
 R10: ffff88000783b4a8 R11: ffff880007b3d878 R12: ffffffff8152da50
 R13: ffff880007b3d868 R14: 0000000000000000 R15: ffff880007b3d800
 FS:  0000000002137880(0063) GS:ffff880007c00000(0000) knlGS:00000000000000=
00
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000422680 CR3: 0000000007b50000 CR4: 00000000000006b0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 0000000000000000 DR7: 0000000000000000
 Process insmod (pid: 43, threadinfo ffff880007b3e000, task ffff880007afb9c=
0)
 Stack:
  ffff880007b3fe58 ffffffff811e66dd ffff880007b3fe58 ffffffff811e570b
  0000000000000010 ffff880007b3d800 ffff880007a7b390 ffff880007b3d868
  0000000000400920 ffff880007b3d800 ffff880007b3fe48 ffffffff8113cfc8
 Call Trace:
  [<ffffffff811e66dd>] ? device_add+0x4bc/0x5af
  [<ffffffff811e570b>] ? dev_set_name+0x3c/0x3e
  [<ffffffff8113cfc8>] sysfs_create_group+0xe/0x12
  [<ffffffff810b420e>] blk_trace_init_sysfs+0x14/0x16
  [<ffffffff8116a090>] blk_register_queue+0x47/0xf7
  [<ffffffff8116f527>] add_disk+0xdf/0x290
  [<ffffffffa00060eb>] loop_init+0xeb/0x1b8 [loop]
  [<ffffffffa0006000>] ? 0xffffffffa0005fff
  [<ffffffff8100020a>] do_one_initcall+0x7a/0x12e
  [<ffffffff81096804>] sys_init_module+0x9c/0x1e0
  [<ffffffff813329bb>] system_call_fastpath+0x16/0x1b
 Code: c3 55 48 89 e5 41 57 41 56 41 89 f6 41 55 41 54 49 89 d4 53 48 89 fb=
 48 83 ec 28 48 85 ff 74 0b 85 f6 75 0b 48 83 7f 30 00 75 14 <0f> 0b eb fe =
48 83 7f 30 00 b9 ea ff ff ff 0f 84 18 01 00 00 49
 RIP  [<ffffffff8113ce61>] internal_create_group+0x2a/0x170
  RSP <ffff880007b3fde8>
 ---[ end trace a123eb592043acad ]---

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-24 16:48:54 +02:00
Jens Axboe
4c63f5646e Merge branch 'for-2.6.39/stack-plug' into for-2.6.39/core
Conflicts:
	block/blk-core.c
	block/blk-flush.c
	drivers/md/raid1.c
	drivers/md/raid10.c
	drivers/md/raid5.c
	fs/nilfs2/btnode.c
	fs/nilfs2/mdt.c

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10 08:58:35 +01:00
Jens Axboe
7eaceaccab block: remove per-queue plugging
Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-10 08:52:07 +01:00
Tejun Heo
e83a46bbb1 Merge branch 'for-linus' of ../linux-2.6-block into block-for-2.6.39/core
This merge creates two set of conflicts.  One is simple context
conflicts caused by removal of throtl_scheduled_delayed_work() in
for-linus and removal of throtl_shutdown_timer_wq() in
for-2.6.39/core.

The other is caused by commit 255bb490c8 (block: blk-flush shouldn't
call directly into q->request_fn() __blk_run_queue()) in for-linus
crashing with FLUSH reimplementation in for-2.6.39/core.  The conflict
isn't trivial but the resolution is straight-forward.

* __blk_run_queue() calls in flush_end_io() and flush_data_end_io()
  should be called with @force_kblockd set to %true.

* elv_insert() in blk_kick_flush() should use
  %ELEVATOR_INSERT_REQUEUE.

Both changes are to avoid invoking ->request_fn() directly from
request completion path and closely match the changes in the commit
255bb490c8.

Signed-off-by: Tejun Heo <tj@kernel.org>
2011-03-04 19:09:02 +01:00
Petr Uzel
fd51469fb6 block: kill loop_mutex
Following steps lead to deadlock in kernel:

dd if=/dev/zero of=img bs=512 count=1000
losetup -f img
mkfs.ext2 /dev/loop0
mount -t ext2 -o loop /dev/loop0 mnt
umount mnt/

Stacktrace:
[<c102ec04>] irq_exit+0x36/0x59
[<c101502c>] smp_apic_timer_interrupt+0x6b/0x75
[<c127f639>] apic_timer_interrupt+0x31/0x38
[<c101df88>] mutex_spin_on_owner+0x54/0x5b
[<fe2250e9>] lo_release+0x12/0x67 [loop]
[<c10c4eae>] __blkdev_put+0x7c/0x10c
[<c10a4da5>] fput+0xd5/0x1aa
[<fe2250cf>] loop_clr_fd+0x1a9/0x1b1 [loop]
[<fe225110>] lo_release+0x39/0x67 [loop]
[<c10c4eae>] __blkdev_put+0x7c/0x10c
[<c10a59d9>] deactivate_locked_super+0x17/0x36
[<c10b6f37>] sys_umount+0x27e/0x2a5
[<c10b6f69>] sys_oldumount+0xb/0xe
[<c1002897>] sysenter_do_call+0x12/0x26
[<ffffffff>] 0xffffffff

Regression since 2a48fc0ab2, which introduced the private
loop_mutex as part of the BKL removal process.

As per [1], the mutex can be safely removed.

[1] http://www.gossamer-threads.com/lists/linux/kernel/1341930

Addresses: https://bugzilla.novell.com/show_bug.cgi?id=669394
Addresses: https://bugzilla.kernel.org/show_bug.cgi?id=29172

Signed-off-by: Petr Uzel <petr.uzel@suse.cz>
Cc: stable@kernel.org
Reviewed-by: Nikanth Karthikesan <knikanth@suse.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-03 11:53:25 -05:00
Vivek Goyal
cd25f54961 loop: No need to initialize ->queue_lock explicitly before calling blk_cleanup_queue()
Now we initialize ->queue_lock at queue allocation time so driver does
not have to worry about initializing it before calling
blk_cleanup_queue().

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-03-02 19:06:49 -05:00
Sergey Senozhatsky
ee71a96867 loop: queue_lock NULL pointer derefence in blk_throtl_exit
Performing
$ sudo mount -o loop -o umask=0 /dev/sdb1 /mnt/
mount: wrong fs type, bad option, bad superblock on /dev/loop0,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

$ sudo modprobe -r loop

results in oops:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000004
 IP: [<ffffffff812479d4>] do_raw_spin_lock+0x14/0x122
 Process modprobe (pid: 6189, threadinfo ffff88009a898000, task ffff880154a88000)
 Call Trace:
  [<ffffffff81486788>] _raw_spin_lock_irq+0x4a/0x51
  [<ffffffff8123404b>] ? blk_throtl_exit+0x3b/0xa0
  [<ffffffff8105b120>] ? cancel_delayed_work_sync+0xd/0xf
  [<ffffffff8123404b>] blk_throtl_exit+0x3b/0xa0
  [<ffffffff81229bc8>] blk_release_queue+0x21/0x65
  [<ffffffff8123bb06>] kobject_release+0x51/0x66
  [<ffffffff8123bab5>] ? kobject_release+0x0/0x66
  [<ffffffff8123ce1e>] kref_put+0x43/0x4d
  [<ffffffff8123ba27>] kobject_put+0x47/0x4b
  [<ffffffff8122717c>] blk_cleanup_queue+0x56/0x5b
  [<ffffffffa01c3824>] loop_exit+0x68/0x844 [loop]
  [<ffffffff8107cccc>] sys_delete_module+0x1e8/0x25b
  [<ffffffff814864c9>] ? trace_hardirqs_on_thunk+0x3a/0x3f
  [<ffffffff81002112>] system_call_fastpath+0x16/0x1b

because of an attempt to acquire NULL queue_lock.
I added the same lines as in blk_queue_make_request -
index 44e18c0..49e6a54 100644`fall back to embedded per-queue lock'.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-19 08:25:02 -07:00
Jens Axboe
3603b8eacc Fix compile warnings due to missing removal of a 'ret' variable
Commit a8adbe3 forgot to remove the return variable, kill it.

drivers/block/loop.c: In function 'lo_splice_actor':
drivers/block/loop.c:398: warning: unused variable 'ret'
[...]
fs/nfsd/vfs.c: In function 'nfsd_splice_actor':
fs/nfsd/vfs.c:848: warning: unused variable 'ret'

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-20 09:15:19 +01:00
Michał Mirosław
a8adbe378b fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
This patch pulls calls to buf->ops->confirm() from all actors passed
(also indirectly) to splice_from_pipe_feed().

Is avoiding the call to buf->ops->confirm() while splice()ing to
/dev/null is an intentional optimization? No other user does that
and this will remove this special case.

Against current linux.git 6313e3c217.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-12-17 08:56:44 +01:00
Christoph Hellwig
02e031cbc8 block: remove REQ_HARDBARRIER
REQ_HARDBARRIER is dead now, so remove the leftovers.  What's left
at this point is:

 - various checks inside the block layer.
 - sanity checks in bio based drivers.
 - now unused bio_empty_barrier helper.
 - Xen blockfront use of BLKIF_OP_WRITE_BARRIER - it's dead for a while,
   but Xen really needs to sort out it's barrier situaton.
 - setting of ordered tags in uas - dead code copied from old scsi
   drivers.
 - scsi different retry for barriers - it's dead and should have been
   removed when flushes were converted to FS requests.
 - blktrace handling of barriers - removed.  Someone who knows blktrace
   better should add support for REQ_FLUSH and REQ_FUA, though.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10 14:54:09 +01:00
Milan Broz
51a0bb0c2e loop: Properly clear sysfs in autoclear mode
In autoclear mode bdev is NULL but the sysfs
entry should be destroyed otherwise this warning appears:

WARNING: at fs/sysfs/dir.c:451 sysfs_add_one+0x82/0x95()
sysfs: cannot create duplicate filename '/devices/virtual/block/loop0/loop'

Fixes commit ee86273062

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-27 19:51:30 -06:00
Peter Zijlstra
61ecdb801e mm: strictly nested kmap_atomic()
Ensure kmap_atomic() usage is strictly nested

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:08 -07:00
Linus Torvalds
a2887097f2 Merge branch 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block: (46 commits)
  xen-blkfront: disable barrier/flush write support
  Added blk-lib.c and blk-barrier.c was renamed to blk-flush.c
  block: remove BLKDEV_IFL_WAIT
  aic7xxx_old: removed unused 'req' variable
  block: remove the BH_Eopnotsupp flag
  block: remove the BLKDEV_IFL_BARRIER flag
  block: remove the WRITE_BARRIER flag
  swap: do not send discards as barriers
  fat: do not send discards as barriers
  ext4: do not send discards as barriers
  jbd2: replace barriers with explicit flush / FUA usage
  jbd2: Modify ASYNC_COMMIT code to not rely on queue draining on barrier
  jbd: replace barriers with explicit flush / FUA usage
  nilfs2: replace barriers with explicit flush / FUA usage
  reiserfs: replace barriers with explicit flush / FUA usage
  gfs2: replace barriers with explicit flush / FUA usage
  btrfs: replace barriers with explicit flush / FUA usage
  xfs: replace barriers with explicit flush / FUA usage
  block: pass gfp_mask and flags to sb_issue_discard
  dm: convey that all flushes are processed as empty
  ...
2010-10-22 17:07:18 -07:00
Linus Torvalds
8abfc6e7a4 Merge branch 'for-2.6.37/drivers' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.37/drivers' of git://git.kernel.dk/linux-2.6-block: (95 commits)
  cciss: fix PCI IDs for new Smart Array controllers
  drbd: add race-breaker to drbd_go_diskless
  drbd: use dynamic_dev_dbg to optionally log uuid changes
  dynamic_debug.h: Fix dynamic_dev_dbg() macro if CONFIG_DYNAMIC_DEBUG not set
  drbd: cleanup: change "<= 0" to "== 0"
  drbd: relax the grace period of the md_sync timer again
  drbd: add some more explicit drbd_md_sync
  drbd: drop wrong debug asserts, fix recently introduced race
  drbd: cleanup useless leftover warn/error printk's
  drbd: add explicit drbd_md_sync to drbd_resync_finished
  drbd: Do not log an ASSERT for P_OV_REQUEST packets while C_CONNECTED
  drbd: fix for possible deadlock on IO error during resync
  drbd: fix unlikely access after free and list corruption
  drbd: fix for spurious fullsync (uuids rotated too fast)
  drbd: allow for explicit resync-finished notifications
  drbd: preparation commit, using full state in receive_state()
  drbd: drbd_send_ack_dp must not rely on header information
  drbd: Fix regression in recv_bm_rle_bits (compressed bitmap)
  drbd: Fixed a stupid copy and paste error
  drbd: Allow larger values for c-fill-target.
  ...

Fix up trivial conflict in drivers/block/ataflop.c due to BKL removal
2010-10-22 17:03:12 -07:00
Arnd Bergmann
2a48fc0ab2 block: autoconvert trivial BKL users to private mutex
The block device drivers have all gained new lock_kernel
calls from a recent pushdown, and some of the drivers
were already using the BKL before.

This turns the BKL into a set of per-driver mutexes.
Still need to check whether this is safe to do.

file=$1
name=$2
if grep -q lock_kernel ${file} ; then
    if grep -q 'include.*linux.mutex.h' ${file} ; then
            sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
    else
            sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
    fi
    sed -i ${file} \
        -e "/^#include.*linux.mutex.h/,$ {
                1,/^\(static\|int\|long\)/ {
                     /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);

} }"  \
    -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
    -e '/[      ]*cycle_kernel_lock();/d'
else
    sed -i -e '/include.*\<smp_lock.h\>/d' ${file}  \
                -e '/cycle_kernel_lock()/d'
fi

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-05 15:01:10 +02:00
Tejun Heo
6259f28459 block/loop: implement REQ_FLUSH/FUA support
Deprecate REQ_HARDBARRIER and implement REQ_FLUSH/FUA instead.  Also,
instead of checking file->f_op->fsync() directly, look at the value of
vfs_fsync() and ignore -EINVAL return.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-10 12:35:37 +02:00
Tejun Heo
4913efe456 block: deprecate barrier and replace blk_queue_ordered() with blk_queue_flush()
Barrier is deemed too heavy and will soon be replaced by FLUSH/FUA
requests.  Deprecate barrier.  All REQ_HARDBARRIERs are failed with
-EOPNOTSUPP and blk_queue_ordered() is replaced with simpler
blk_queue_flush().

blk_queue_flush() takes combinations of REQ_FLUSH and FUA.  If a
device has write cache and can flush it, it should set REQ_FLUSH.  If
the device can handle FUA writes, it should also set REQ_FUA.

All blk_queue_ordered() users are converted.

* ORDERED_DRAIN is mapped to 0 which is the default value.
* ORDERED_DRAIN_FLUSH is mapped to REQ_FLUSH.
* ORDERED_DRAIN_FLUSH_FUA is mapped to REQ_FLUSH | REQ_FUA.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-10 12:35:36 +02:00
Tejun Heo
589d7ed02a block/loop: queue ordered mode should be DRAIN_FLUSH
loop implements FLUSH using fsync but was incorrectly setting its
ordered mode to DRAIN.  Change it to DRAIN_FLUSH.  In practice, this
doesn't change anything as loop doesn't make use of the block layer
ordered implementation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-10 12:35:36 +02:00
Milan Broz
ee86273062 loop: add some basic read-only sysfs attributes
Create /sys/block/loopX/loop directory and provide these attributes:
 - backing_file
 - autoclear
 - offset
 - sizelimit

This loop directory is present only if loop device is configured.

To be used in util-linux-ng (and possibly elsewhere like udev rules)
where code need to get loop attributes from kernel (and not store
duplicate info in userspace).

Moreover loop ioctls are not even able to provide full backing
file info because of buffer limits.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-23 15:18:10 +02:00
Jiri Slaby
5e00d1b5b4 BLOCK: fix bio.bi_rw handling
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>
2010-08-23 12:33:10 +02:00
Arnd Bergmann
6e9624b8ca block: push down BKL into .open and .release
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>
2010-08-07 18:25:34 +02:00
FUJITA Tomonori
00fff26539 block: remove q->prepare_flush_fn completely
This removes q->prepare_flush_fn completely (changes the
blk_queue_ordered API).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:24:15 +02:00
Christoph Hellwig
7b6d91daee block: unify flags for struct bio and struct request
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>
2010-08-07 18:20:39 +02:00