Commit Graph

259 Commits

Author SHA1 Message Date
Christoph Hellwig aebf526b53 block: fold cmd_type into the REQ_OP_ space
Instead of keeping two levels of indirection for requests types, fold it
all into the operations.  The little caveat here is that previously
cmd_type only applied to struct request, while the request and bio op
fields were set to plain REQ_OP_READ/WRITE even for passthrough
operations.

Instead this patch adds new REQ_OP_* for SCSI passthrough and driver
private requests, althought it has to add two for each so that we
can communicate the data in/out nature of the request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-31 14:00:44 -07:00
Christoph Hellwig 09fc54ccc4 nbd: move request validity checking into nbd_send_cmd
This is where we do the rest of the request handling, which will
become much simpler soon, too.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-31 14:00:29 -07:00
Christoph Hellwig 27410a8927 nbd: remove REQ_TYPE_DRV_PRIV leftovers
Disconnects don't use block layer requests these days, so all handling
of private requests is dead code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-31 14:00:25 -07:00
Josef Bacik d61b7f972d nbd: only set MSG_MORE when we have more to send
A user noticed that write performance was horrible over loopback and we
traced it to an inversion of when we need to set MSG_MORE.  It should be
set when we have more bvec's to send, not when we are on the last bvec.
This patch made the test go from 20 iops to 78k iops.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Fixes: 429a787be6 ("nbd: fix use-after-free of rq/bio in the xmit path")
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-19 14:31:50 -07:00
Jeff Moyer 25b4acfc7d nbd: blk_mq_init_queue returns an error code on failure, not NULL
Additionally, don't assign directly to disk->queue, otherwise
blk_put_queue (called via put_disk) will choke (panic) on the errno
stored there.

Bug found by code inspection after Omar found a similar issue in
virtio_blk.  Compile-tested only.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-10 13:30:50 -07:00
Al Viro c9f2b6aeb9 [nbd] pass iov_iter to nbd_xmit()
... and don't mess with kmap() - just use BVEC_ITER for those parts.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-26 21:35:13 -05:00
Al Viro c1696cab70 [nbd] switch sock_xmit() to sock_{send,recv}msg()
Step 1 - don't reinintialize ->msg_iter on each iteration.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-26 21:21:23 -05:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Josef Bacik a897b6664e nbd: use dev_err_ratelimited in io path
While doing stress tests we noticed that we'd get a lot of dmesg spam if
we suddenly disconnected the nbd device out of band.  Rate limit the
messages in the io path in order to deal with this.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-08 15:28:09 -07:00
Josef Bacik 20032ec38d nbd: reset the setup task for NBD_CLEAR_SOCK
If an app exits before running NBD_DO_IT but after adding sockets we can
end up not being allowed to do a new nbd device.  Fix this by making
NBD_CLEAR_SOCK reset the setup_task.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-08 15:26:57 -07:00
Jens Axboe e88f72cb9f nbd: fix 64-bit division
We have this:

ERROR: "__aeabi_ldivmod" [drivers/block/nbd.ko] undefined!
ERROR: "__divdi3" [drivers/block/nbd.ko] undefined!
nbd.c:(.text+0x247c72): undefined reference to `__divdi3'

due to a recent commit, that did 64-bit division. Use the proper
divider function so that 32-bit compiles don't break.

Fixes: ef77b51524 ("nbd: use loff_t for blocksize and nbd_set_size args")
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-03 12:08:03 -07:00
Josef Bacik ef77b51524 nbd: use loff_t for blocksize and nbd_set_size args
If we have large devices (say like the 40t drive I was trying to test with) we
will end up overflowing the int arguments to nbd_set_size and not get the right
size for our device.  Fix this by using loff_t everywhere so I don't have to
think about this again.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-02 21:06:29 -07:00
Jens Axboe feffa5cc7b nbd: fix setting of 'error' in NBD_DO_IT ioctl
Multiple paths don't set it properly, ensure that we do.

Fixes: 9561a7ade0 ("nbd: add multi-connection support")
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-22 19:09:45 -07:00
Josef Bacik 9561a7ade0 nbd: add multi-connection support
NBD can become contended on its single connection.  We have to serialize all
writes and we can only process one read response at a time.  Fix this by
allowing userspace to provide multiple connections to a single nbd device.  This
coupled with block-mq drastically increases performance in multi-process cases.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-22 12:16:32 -07:00
Jens Axboe 429a787be6 nbd: fix use-after-free of rq/bio in the xmit path
For writes, we can get a completion in while we're still iterating
the request and bio chain. If that happens, we're reading freed
memory and we can crash.

Break out after the last segment and avoid having the iterator
read freed memory.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-17 12:30:37 -07:00
Linus Torvalds 12e3d3cdd9 Merge branch 'for-4.9/block-irq' of git://git.kernel.dk/linux-block
Pull blk-mq irq/cpu mapping updates from Jens Axboe:
 "This is the block-irq topic branch for 4.9-rc. It's mostly from
  Christoph, and it allows drivers to specify their own mappings, and
  more importantly, to share the blk-mq mappings with the IRQ affinity
  mappings. It's a good step towards making this work better out of the
  box"

* 'for-4.9/block-irq' of git://git.kernel.dk/linux-block:
  blk_mq: linux/blk-mq.h does not include all the headers it depends on
  blk-mq: kill unused blk_mq_create_mq_map()
  blk-mq: get rid of the cpumask in struct blk_mq_tags
  nvme: remove the post_scan callout
  nvme: switch to use pci_alloc_irq_vectors
  blk-mq: provide a default queue mapping for PCI device
  blk-mq: allow the driver to pass in a queue mapping
  blk-mq: remove ->map_queue
  blk-mq: only allocate a single mq_map per tag_set
  blk-mq: don't redistribute hardware queues on a CPU hotplug event
2016-10-09 17:29:33 -07:00
Josef Bacik 005043ac31 nbd: use BLK_MQ_F_BLOCKING
We take a mutex when sending commands and send stuff over the network, we need
to have queue_rq called asynchronously.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Fixes: fd8383fd88 ("nbd: convert to blkmq")
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-23 11:46:42 -06:00
Josef Bacik 0eadf37afc nbd: allow block mq to deal with timeouts
Instead of rolling our own timer, just utilize the blk mq req timeout and do the
disconnect if any of our commands timeout.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-08 14:01:37 -06:00
Josef Bacik 9b4a6ba918 nbd: use flags instead of bool
In preparation for some future changes, change a few of the state bools over to
normal bits to set/clear properly.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-08 14:01:35 -06:00
Josef Bacik c261189862 nbd: don't shutdown sock with irq's disabled
We hit a warning when shutting down the nbd connection because we have irq's
disabled.  We don't really need to do the shutdown under the lock, just clear
the nbd->sock.  So do the shutdown outside of the irq.  This gets rid of the
warning.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-08 14:01:34 -06:00
Josef Bacik fd8383fd88 nbd: convert to blkmq
This moves NBD over to using blkmq, which allows us to get rid of the NBD
wide queue lock and the async submit kthread.  We will start with 1 hw
queue for now, but I plan to add multiple tcp connection support in the
future and we'll fix how we set the hwqueue's.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-08 14:01:32 -06:00
Vegard Nossum 97240963eb nbd: fix race in ioctl
Quentin ran into this bug:

WARNING: CPU: 64 PID: 10085 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x65/0x80
sysfs: cannot create duplicate filename '/devices/virtual/block/nbd3/pid'
Modules linked in: nbd
CPU: 64 PID: 10085 Comm: qemu-nbd Tainted: G      D         4.6.0+ #7
 0000000000000000 ffff8820330bba68 ffffffff814b8791 ffff8820330bbac8
 0000000000000000 ffff8820330bbab8 ffffffff810d04ab ffff8820330bbaa8
 0000001f00000296 0000000000017681 ffff8810380bf000 ffffffffa0001790
Call Trace:
 [<ffffffff814b8791>] dump_stack+0x4d/0x6c
 [<ffffffff810d04ab>] __warn+0xdb/0x100
 [<ffffffff810d0574>] warn_slowpath_fmt+0x44/0x50
 [<ffffffff81218c65>] sysfs_warn_dup+0x65/0x80
 [<ffffffff81218a02>] sysfs_add_file_mode_ns+0x172/0x180
 [<ffffffff81218a35>] sysfs_create_file_ns+0x25/0x30
 [<ffffffff81594a76>] device_create_file+0x36/0x90
 [<ffffffffa0000e8d>] __nbd_ioctl+0x32d/0x9b0 [nbd]
 [<ffffffff814cc8e8>] ? find_next_bit+0x18/0x20
 [<ffffffff810f7c29>] ? select_idle_sibling+0xe9/0x120
 [<ffffffff810f6cd7>] ? __enqueue_entity+0x67/0x70
 [<ffffffff810f9bf0>] ? enqueue_task_fair+0x630/0xe20
 [<ffffffff810efa76>] ? resched_curr+0x36/0x70
 [<ffffffff810f0078>] ? check_preempt_curr+0x78/0x90
 [<ffffffff810f00a2>] ? ttwu_do_wakeup+0x12/0x80
 [<ffffffff810f01b1>] ? ttwu_do_activate.constprop.86+0x61/0x70
 [<ffffffff810f0c15>] ? try_to_wake_up+0x185/0x2d0
 [<ffffffff810f0d6d>] ? default_wake_function+0xd/0x10
 [<ffffffff81105471>] ? autoremove_wake_function+0x11/0x40
 [<ffffffffa0001577>] nbd_ioctl+0x67/0x94 [nbd]
 [<ffffffff814ac0fd>] blkdev_ioctl+0x14d/0x940
 [<ffffffff811b0da2>] ? put_pipe_info+0x22/0x60
 [<ffffffff811d96cc>] block_ioctl+0x3c/0x40
 [<ffffffff811ba08d>] do_vfs_ioctl+0x8d/0x5e0
 [<ffffffff811aa329>] ? ____fput+0x9/0x10
 [<ffffffff810e9092>] ? task_work_run+0x72/0x90
 [<ffffffff811ba627>] SyS_ioctl+0x47/0x80
 [<ffffffff8185f5df>] entry_SYSCALL_64_fastpath+0x17/0x93
---[ end trace 7899b295e4f850c8 ]---

It seems fairly obvious that device_create_file() is not being protected
from being run concurrently on the same nbd.

Quentin found the following relevant commits:

1a2ad21 nbd: add locking to nbd_ioctl
90b8f28 [PATCH] end of methods switch: remove the old ones
d4430d6 [PATCH] beginning of methods conversion
08f8585 [PATCH] move block_device_operations to blkdev.h

It would seem that the race was introduced in the process of moving nbd
from BKL to unlocked ioctls.

By setting nbd->task_recv while the mutex is held, we can prevent other
processes from running concurrently (since nbd->task_recv is also checked
while the mutex is held).

Reported-and-tested-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Pavel Machek <pavel@suse.cz>
Cc: Jens Axboe <axboe@fb.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-08-04 14:19:16 -06:00
Linus Torvalds d05d7f4079 Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:

   - the big change is the cleanup from Mike Christie, cleaning up our
     uses of command types and modified flags.  This is what will throw
     some merge conflicts

   - regression fix for the above for btrfs, from Vincent

   - following up to the above, better packing of struct request from
     Christoph

   - a 2038 fix for blktrace from Arnd

   - a few trivial/spelling fixes from Bart Van Assche

   - a front merge check fix from Damien, which could cause issues on
     SMR drives

   - Atari partition fix from Gabriel

   - convert cfq to highres timers, since jiffies isn't granular enough
     for some devices these days.  From Jan and Jeff

   - CFQ priority boost fix idle classes, from me

   - cleanup series from Ming, improving our bio/bvec iteration

   - a direct issue fix for blk-mq from Omar

   - fix for plug merging not involving the IO scheduler, like we do for
     other types of merges.  From Tahsin

   - expose DAX type internally and through sysfs.  From Toshi and Yigal

* 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits)
  block: Fix front merge check
  block: do not merge requests without consulting with io scheduler
  block: Fix spelling in a source code comment
  block: expose QUEUE_FLAG_DAX in sysfs
  block: add QUEUE_FLAG_DAX for devices to advertise their DAX support
  Btrfs: fix comparison in __btrfs_map_block()
  block: atari: Return early for unsupported sector size
  Doc: block: Fix a typo in queue-sysfs.txt
  cfq-iosched: Charge at least 1 jiffie instead of 1 ns
  cfq-iosched: Fix regression in bonnie++ rewrite performance
  cfq-iosched: Convert slice_resid from u64 to s64
  block: Convert fifo_time from ulong to u64
  blktrace: avoid using timespec
  block/blk-cgroup.c: Declare local symbols static
  block/bio-integrity.c: Add #include "blk.h"
  block/partition-generic.c: Remove a set-but-not-used variable
  block: bio: kill BIO_MAX_SIZE
  cfq-iosched: temporarily boost queue priority for idle classes
  block: drbd: avoid to use BIO_MAX_SIZE
  block: bio: remove BIO_MAX_SECTORS
  ...
2016-07-26 15:03:07 -07:00
Josef Bacik d366a0ff1c nbd: pass the nbd pointer for flags debugfs
We were passing in &nbd for the private data in debugfs_create_file() for the
flags entry.  We expect it to just be nbd, fix this so we get proper output from
this debugfs entry.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-08 09:03:54 -06:00
Mike Christie 3a5e02ced1 block, drivers: add REQ_OP_FLUSH operation
This adds a REQ_OP_FLUSH operation that is sent to request_fn
based drivers by the block layer's flush code, instead of
sending requests with the request->cmd_flags REQ_FLUSH bit set.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07 13:41:38 -06:00
Mike Christie c2df40dfb8 drivers: use req op accessor
The req operation REQ_OP is separated from the rq_flag_bits
definition. This converts the block layer drivers to
use req_op to get the op from the request struct.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-07 13:41:38 -06:00
Jens Axboe aafb1eecbb nbd: switch to using blk_queue_write_cache()
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-04-12 16:00:39 -06:00
Arnd Bergmann 5e454c67fc nbd: use correct div_s64 helper
The do_div() macro now checks its arguments for the correct type,
and refuses anything other than u64, so we get a warning about
nbd_ioctl passing in an loff_t:

drivers/block/nbd.c: In function '__nbd_ioctl':
drivers/block/nbd.c:757:77: error: comparison of distinct pointer types lacks a cast [-Werror]

This changes the nbd code to use div_s64() instead, which takes
a signed argument.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 37091fdd83 ("nbd: Create size change events for userspace")
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-04 17:20:12 -07:00
Markus Pargmann 37091fdd83 nbd: Create size change events for userspace
The userspace needs to know when nbd devices are ready for use.
Currently no events are created for the userspace which doesn't work for
systemd.

See the discussion here: https://github.com/systemd/systemd/pull/358

This patch uses a central point to setup the nbd-internal sizes. A ioctl
to set a size does not lead to a visible size change. The size of the
block device will be kept at 0 until nbd is connected. As soon as it
connects, the size will be changed to the real value and a uevent is
created. When disconnecting, the blockdevice is set to 0 size and
another uevent is generated.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
2016-02-15 10:35:47 +01:00
Dan Streetman da6ccaaa79 nbd: ratelimit error msgs after socket close
Make the "Attempted send on closed socket" error messages generated in
nbd_request_handler() ratelimited.

When the nbd socket is shutdown, the nbd_request_handler() function emits
an error message for every request remaining in its queue.  If the queue
is large, this will spam a large amount of messages to the log.  There's
no need for a separate error message for each request, so this patch
ratelimits it.

In the specific case this was found, the system was virtual and the error
messages were logged to the serial port, which overwhelmed it.

Fixes: 4d48a542b4 ("nbd: fix I/O hang on disconnected nbds")
Signed-off-by: Dan Streetman <dan.streetman@canonical.com>
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
2016-02-05 08:55:15 +01:00
Markus Pargmann d02cf53107 nbd: Move flag parsing to a function
nbd changes properties of the blockdevice depending on flags that were
received. This patch moves this flag parsing into a separate function
nbd_parse_flags().

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
2016-02-05 08:52:33 +01:00
Markus Pargmann 0e4f0f6f63 nbd: Cleanup reset of nbd and bdev after a disconnect
Group all variables that are reset after a disconnect into reset
functions. This patch adds two of these functions, nbd_reset() and
nbd_bdev_reset().

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
2016-02-05 08:52:32 +01:00
Markus Pargmann 1f7b5cf1be nbd: Timeouts are not user requested disconnects
It may be useful to know in the client that a connection timed out. The
current code returns success for a timeout.

This patch reports the error code -ETIMEDOUT for a timeout.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
2016-02-05 08:52:31 +01:00
Markus Pargmann 23272a6754 nbd: Remove signal usage
As discussed on the mailing list, the usage of signals for timeout
handling has a lot of potential issues. The nbd driver used for some
time signals for timeouts. These signals where able to get the threads
out of the blocking socket operations.

This patch removes all signal usage and uses a socket shutdown instead.
The socket descriptor itself is cleared later when the whole nbd device
is closed.

The tasks_lock is removed as we do not depend on this anymore. Instead
a new lock for the socket is introduced so we can safely work with the
socket in the timeout handler outside of the two main threads.

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-02-05 08:52:25 +01:00
Markus Pargmann 27ea43fe2a nbd: Fix debugfs error handling
Static checker complains about the implemented error handling. It is
indeed wrong. We don't care about the return values of created debugfs
files.

We only have to check the return values of created dirs for NULL
pointer. If we use a null pointer as parent directory for files, this
may lead to debugfs files in wrong places.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
2016-02-03 11:02:56 +01:00
Al Viro 263a3df18f nbd: use ->compat_ioctl()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-08 21:20:32 -05:00
Oleg Nesterov be0e6f290f signal: turn dequeue_signal_lock() into kernel_dequeue_signal()
1. Rename dequeue_signal_lock() to kernel_dequeue_signal(). This
   matches another "for kthreads only" kernel_sigaction() helper.

2. Remove the "tsk" and "mask" arguments, they are always current
   and current->blocked. And it is simply wrong if tsk != current.

3. We could also remove the 3rd "siginfo_t *info" arg but it looks
   potentially useful. However we can simplify the callers if we
   change kernel_dequeue_signal() to accept info => NULL.

4. Remove _irqsave, it is never called from atomic context.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Tejun Heo <tj@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Markus Pargmann dcc909d90c nbd: Add locking for tasks
The timeout handling introduced in
	7e2893a16d (nbd: Fix timeout detection)
introduces a race condition which may lead to killing of tasks that are
not in nbd context anymore. This was not observed or reproducable yet.

This patch adds locking to critical use of task_recv and task_send to
avoid killing tasks that already left the NBD thread functions. This
lock is only acquired if a timeout occures or the nbd device
starts/stops.

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Reviewed-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 7e2893a16d ("nbd: Fix timeout detection")
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-10-08 14:21:24 -06:00
Markus Pargmann 22d109c1bb nbd: flags is a u32 variable
The flags variable is used as u32 variable. This patch changes the type
to be u32.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:23:01 -06:00
Markus Pargmann cad73b2703 nbd: Rename functions for clearness of recv/send path
This patch renames functions so that it is clear what the function does.
Otherwise it is not directly understandable what for example 'do_it' means.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:59 -06:00
Markus Pargmann 696697cb50 nbd: Change 'disconnect' to be boolean
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek  <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:58 -06:00
Markus Pargmann 30d53d9c11 nbd: Add debugfs entries
Add some debugfs files that help to understand the internal state of
NBD. This exports the different sizes, flags, tasks and so on.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:56 -06:00
Markus Pargmann 6521d39a64 nbd: Remove variable 'pid'
This patch uses nbd->task_recv to determine the value of the previously
used variable 'pid' for sysfs.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:55 -06:00
Markus Pargmann e78273c80b nbd: Move clear queue debug message
This message was a warning without a reason. This patch moves it into
nbd_clear_que and transforms it to a debug message.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:53 -06:00
Markus Pargmann 193918307f nbd: Remove 'harderror' and propagate error properly
Instead of a variable 'harderror' we can simply try to correctly
propagate errors to the userspace.

This patch removes the harderror variable and passes errors through
error pointers and nbd_do_it back to the userspace.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:52 -06:00
Markus Pargmann 260bbce403 nbd: restructure sock_shutdown
This patch restructures sock_shutdown to avoid having the main code path
in an if block.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:50 -06:00
Markus Pargmann 36e47bee7c nbd: sock_shutdown, remove conditional lock
Move the conditional lock from sock_shutdown into the surrounding code.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:49 -06:00
Markus Pargmann 7e2893a16d nbd: Fix timeout detection
At the moment the nbd timeout just detects hanging tcp operations. This
is not enough to detect a hanging or bad connection as expected of a
timeout.

This patch redesigns the timeout detection to include some more cases.
The timeout is now in relation to replies from the server. If the server
does not send replies within the timeout the connection will be shut
down.

The patch adds a continous timer 'timeout_timer' that is setup in one of
two cases:
 - The request list is empty and we are sending the first request out to
   the server. We want to have a reply within the given timeout,
   otherwise we consider the connection to be dead.
 - A server response was received. This means the server is still
   communicating with us. The timer is reset to the timeout value.

The timer is not stopped if the list becomes empty. It will just trigger
a timeout which will directly leave the handling routine again as the
request list is empty.

The whole patch does not use any additional explicit locking. The
list_empty() calls are safe to be used concurrently. The timer is locked
internally as we just use mod_timer and del_timer_sync().

The patch is based on the idea of Michal Belczyk with a previous
different implementation.

Cc: Michal Belczyk <belczyk@bsd.krakow.pl>
Cc: Hermann Lauer <Hermann.Lauer@iwr.uni-heidelberg.de>
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Tested-by: Hermann Lauer <Hermann.Lauer@iwr.uni-heidelberg.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-08-17 08:22:47 -06:00
Jens Axboe 2bb4cd5cc4 block: have drivers use blk_queue_max_discard_sectors()
Some drivers use it now, others just set the limits field manually.
But in preparation for splitting this into a hard and soft limit,
ensure that they all call the proper function for setting the hw
limit for discards.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-17 08:41:53 -06:00
Ming Lei 9dcd137953 block: nbd: convert to blkdev_reread_part()
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-20 09:06:13 -06:00
Christoph Hellwig 9dc6c806b3 nbd: stop using req->cmd
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-05 13:40:44 -06:00
Christoph Hellwig 4f8c9510ba block: rename REQ_TYPE_SPECIAL to REQ_TYPE_DRV_PRIV
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-05 13:40:03 -06:00
Markus Pargmann de9ad6d4ed nbd: Return error pointer directly
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-02 12:39:28 -06:00
Markus Pargmann dab5313aa4 nbd: Return error code directly
By returning the error code directly, we can avoid the jump label
error_out.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-02 12:39:26 -06:00
Markus Pargmann e018e7570c nbd: Remove fixme that was already fixed
The mentioned problem is not present anymore.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-02 12:39:24 -06:00
Markus Pargmann d18509f597 nbd: Restructure debugging prints
dprintk has some name collisions with other frameworks and drivers. It
is also not necessary to have these custom debug print filters. Dynamic
debug offers the same amount of filtered debugging.

This patch replaces all dprintks with dev_dbg(). It also removes the
ioctl dprintk which prints the ingoing ioctls which should be
replaceable by strace or similar stuff.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-02 12:39:22 -06:00
Markus Pargmann b9c495bb6d nbd: Fix device bytesize type
The block subsystem uses loff_t to store the device size. Change the
type for nbd_device bytesize to loff_t.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-02 12:39:21 -06:00
Markus Pargmann d06df60b94 nbd: Replace kthread_create with kthread_run
kthread_run includes the wake_up_process() call, so instead of
kthread_create() followed by wake_up_process() we can use this macro.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-02 12:39:19 -06:00
Markus Pargmann 13e71d69cc nbd: Remove kernel internal header
The header is not included anywhere. Remove it and include the private
nbd_device struct in nbd.c.

Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-02 12:39:18 -06:00
Sudip Mukherjee ff6b8090e2 nbd: fix possible memory leak
we have already allocated memory for nbd_dev, but we were not
releasing that memory and just returning the error value.

Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Acked-by: Paul Clements <Paul.Clements@SteelEye.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
2015-03-05 08:51:03 +01:00
Mike Snitzer b277da0a8a block: disable entropy contributions for nonrot devices
Clear QUEUE_FLAG_ADD_RANDOM in all block drivers that set
QUEUE_FLAG_NONROT.

Historically, all block devices have automatically made entropy
contributions.  But as previously stated in commit e2e1a148 ("block: add
sysfs knob for turning off disk entropy contributions"):
    - On SSD disks, the completion times aren't as random as they
      are for rotational drives. So it's questionable whether they
      should contribute to the random pool in the first place.
    - Calling add_disk_randomness() has a lot of overhead.

There are more reliable sources for randomness than non-rotational block
devices.  From a security perspective it is better to err on the side of
caution than to allow entropy contributions from unreliable "random"
sources.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-10-04 10:55:32 -06:00
Hani Benhabiles 04cfac4e40 nbd: zero from and len fields in NBD_CMD_DISCONNECT.
Len field is already set to zero, but not the from field which is sent
as 0xfffffffffffffe00.  This makes no sense, and may cause confuse
server implementations doing sanity checks (qemu-nbd is an example.)

Signed-off-by: Hani Benhabiles <hani@linux.com>
Cc: Paul Clements <paul.clements@us.sios.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 16:08:18 -07:00
Ingo Molnar 2fe5de9ce7 Merge branch 'sched/urgent' into sched/core, to avoid conflicts
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-07 13:15:46 +02:00
Dongsheng Yang 8698a745d8 sched, treewide: Replace hardcoded nice values with MIN_NICE/MAX_NICE
Replace various -20/+19 hardcoded nice values with MIN_NICE/MAX_NICE.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/ff13819fd09b7a5dba5ab5ae797f2e7019bdfa17.1394532288.git.yangds.fnst@cn.fujitsu.com
Cc: devel@driverdev.osuosl.org
Cc: devicetree@vger.kernel.org
Cc: fcoe-devel@open-fcoe.org
Cc: linux390@de.ibm.com
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-s390@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: nbd-general@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: openipmi-developer@lists.sourceforge.net
Cc: qla2xxx-upstream@qlogic.com
Cc: linux-arch@vger.kernel.org
[ Consolidated the patches, twiddled the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18 12:07:24 +02:00
Al Viro e25115786e switch nbd to sockfd_lookup/sockfd_put
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:10 -04:00
Kent Overstreet 4550dd6c6b block: Immutable bio vecs
This adds a mechanism by which we can advance a bio by an arbitrary
number of bytes without modifying the biovec: bio->bi_iter.bi_bvec_done
indicates the number of bytes completed in the current bvec.

Various driver code still needs to be updated to not refer to the bvec
directly before we can use this for interesting things, like efficient
bio splitting.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
2013-11-23 22:33:49 -08:00
Kent Overstreet 7988613b0e block: Convert bio_for_each_segment() to bvec_iter
More prep work for immutable biovecs - with immutable bvecs drivers
won't be able to use the biovec directly, they'll need to use helpers
that take into account bio->bi_iter.bi_bvec_done.

This updates callers for the new usage without changing the
implementation yet.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: Jim Paris <jim@jtan.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Cc: support@lsi.com
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Quoc-Son Anh <quoc-sonx.anh@intel.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-m68k@lists.linux-m68k.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: drbd-user@lists.linbit.com
Cc: nbd-general@lists.sourceforge.net
Cc: cbe-oss-dev@lists.ozlabs.org
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Cc: linux-raid@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: DL-MPTFusionLinux@lsi.com
Cc: linux-scsi@vger.kernel.org
Cc: devel@driverdev.osuosl.org
Cc: linux-fsdevel@vger.kernel.org
Cc: cluster-devel@redhat.com
Cc: linux-mm@kvack.org
Acked-by: Geoff Levand <geoff@infradead.org>
2013-11-23 22:33:49 -08:00
Paul Clements c378f70adb nbd: correct disconnect behavior
Currently, when a disconnect is requested by the user (via NBD_DISCONNECT
ioctl) the return from NBD_DO_IT is undefined (it is usually one of
several error codes).  This means that nbd-client does not know if a
manual disconnect was performed or whether a network error occurred.
Because of this, nbd-client's persist mode (which tries to reconnect after
error, but not after manual disconnect) does not always work correctly.

This change fixes this by causing NBD_DO_IT to always return 0 if a user
requests a disconnect.  This means that nbd-client can correctly either
persist the connection (if an error occurred) or disconnect (if the user
requested it).

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Acked-by: Rob Landley <rob@landley.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:08:05 -07:00
Michal Belczyk 9532f149ee nbd: remove bogus BUG_ON in NBD_CLEAR_QUE
The NBD_CLEAR_QUE ioctl has been deprecated for quite some time (its job
is now done by two other ioctls).  We should stop trying to make bogus
assertions in it.  Also, user-level code should remove calls to
NBD_CLEAR_QUE, ASAP.

Signed-off-by: Michal Belczyk <belczyk@bsd.krakow.pl>
Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:08:05 -07:00
Kees Cook ffc8b30866 block: do not pass disk names as format strings
Disk names may contain arbitrary strings, so they must not be
interpreted as format strings.  It seems that only md allows arbitrary
strings to be used for disk names, but this could allow for a local
memory corruption from uid 0 into ring 0.

CVE-2013-2851

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:25 -07:00
Michal Belczyk 078be02b80 nbd: increase default and max request sizes
Raise the default max request size for nbd to 128KB (from 127KB) to get it
4KB aligned.  This patch also allows the max request size to be increased
(via /sys/block/nbd<x>/queue/max_sectors_kb) to 32MB.

The patch makes nbd network traffic more efficient by:
- reducing request fragmentation (4KB alignment)
- reducing the number of requests (fewer round trips, less network overhead)

Especially in high latency networks, larger request size can make a dramatic

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Michal Belczyk <belczyk@bsd.krakow.pl>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:07 -07:00
Alex Elder 398eb08555 nbd: fix sparse warning
I just fixed this in "drivers/block/rbd.c" and I noticed that
"drivers/block/nbd.c" has the same problem.  Fix a warning issued by
sparse by adding some lockdep annotations to indicate the queue lock gets
dropped (because it's held when do_nbd_request() is called) and
re-acquired within the function.

Signed-off-by: Alex Elder <elder@inktank.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Paul Clements <paul.clements@us.sios.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:22 -08:00
Paolo Bonzini a83e814b5b nbd: show read-only state in sysfs
Pass the read-only flag to set_device_ro, so that it will be visible to
the block layer and in sysfs.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:22 -08:00
Paolo Bonzini 3a2d63f879 nbd: fsync and kill block device on shutdown
There are two problems with shutdown in the NBD driver.

1: Receiving the NBD_DISCONNECT ioctl does not sync the filesystem.

   This patch adds the sync operation into __nbd_ioctl()'s
   NBD_DISCONNECT handler.  This is useful because BLKFLSBUF is restricted
   to processes that have CAP_SYS_ADMIN, and the NBD client may not
   possess it (fsync of the block device does not sync the filesystem,
   either).

2: Once we clear the socket we have no guarantee that later reads will
   come from the same backing storage.

   The patch adds calls to kill_bdev() in __nbd_ioctl()'s socket
   clearing code so the page cache is cleaned, lest reads that hit on the
   page cache will return stale data from the previously-accessible disk.

Example:

    # qemu-nbd -r -c/dev/nbd0 /dev/sr0
    # file -s /dev/nbd0
    /dev/stdin: # UDF filesystem data (version 1.5) etc.
    # qemu-nbd -d /dev/nbd0
    # qemu-nbd -r -c/dev/nbd0 /dev/sda
    # file -s /dev/nbd0
    /dev/stdin: # UDF filesystem data (version 1.5) etc.

While /dev/sda has:

    # file -s /dev/sda
    /dev/sda: x86 boot sector; etc.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Paul Clements <Paul.Clements@steeleye.com>
Cc: Alex Bligh <alex@alex.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:22 -08:00
Alex Bligh 75f187aba5 nbd: support FLUSH requests
Currently, the NBD device does not accept flush requests from the Linux
block layer.  If the NBD server opened the target with neither O_SYNC nor
O_DSYNC, however, the device will be effectively backed by a writeback
cache.  Without issuing flushes properly, operation of the NBD device will
not be safe against power losses.

The NBD protocol has support for both a cache flush command and a FUA
command flag; the server will also pass a flag to note its support for
these features.  This patch adds support for the cache flush command and
flag.  In the kernel, we receive the flags via the NBD_SET_FLAGS ioctl,
and map NBD_FLAG_SEND_FLUSH to the argument of blk_queue_flush.  When the
flag is active the block layer will send REQ_FLUSH requests, which we
translate to NBD_CMD_FLUSH commands.

FUA support is not included in this patch because all free software
servers implement it with a full fdatasync; thus it has no advantage over
supporting flush only.  Because I [Paolo] cannot really benchmark it in a
realistic scenario, I cannot tell if it is a good idea or not.  It is also
not clear if it is valid for an NBD server to support FUA but not flush.
The Linux block layer gives a warning for this combination, the NBD
protocol documentation says nothing about it.

The patch also fixes a small problem in the handling of flags: nbd->flags
must be cleared at the end of NBD_DO_IT, but the driver was not doing
that.  The bug manifests itself as follows.  Suppose you two different
client/server pairs to start the NBD device.  Suppose also that the first
client supports NBD_SET_FLAGS, and the first server sends
NBD_FLAG_SEND_FLUSH; the second pair instead does neither of these two
things.  Before this patch, the second invocation of NBD_DO_IT will use a
stale value of nbd->flags, and the second server will issue an error every
time it receives an NBD_CMD_FLUSH command.

This bug is pre-existing, but it becomes much more important after this
patch; flush failures make the device pretty much unusable, unlike

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Bligh <alex@alex.org.uk>
Acked-by: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:22 -08:00
Al Viro 496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Paul Clements a336d29870 nbd: handle discard requests
Add discard support to nbd.  If the nbd-server supports discard, it will
send NBD_FLAG_SEND_TRIM to the client.  The client will then set the flag
in the kernel via NBD_SET_FLAGS, which tells the kernel to enable discards
for the device (QUEUE_FLAG_DISCARD).

If discard support is enabled, then when the nbd client system receives a
discard request, this will be passed along to the nbd-server.  When the
discard request is received by the nbd-server, it will perform:

	fallocate(.. FALLOC_FL_PUNCH_HOLE ..)

To punch a hole in the backend storage, which is no longer needed.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:24 +09:00
Paul Clements 2f01250888 nbd: add set flags ioctl
Add a set-flags ioctl, allowing various option flags to be set on an nbd
device.  This allows the nbd-client to set the device flags (to enable
read-only mode, or enable discard support, etc.).

Flags are typically specified by the nbd-server.  During the negotiation
phase of the nbd connection, the server sends its flags to the client.
The client then uses NBD_SET_FLAGS to inform the kernel of the options.

Also included is a one-line fix to debug output for the set-timeout ioctl.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06 03:05:23 +09:00
Paul Clements fded4e090c nbd: clear waiting_queue on shutdown
Fix a serious but uncommon bug in nbd which occurs when there is heavy
I/O going to the nbd device while, at the same time, a failure (server,
network) or manual disconnect of the nbd connection occurs.

There is a small window between the time that the nbd_thread is stopped
and the socket is shutdown where requests can continue to be queued to
nbd's internal waiting_queue.  When this happens, those requests are
never completed or freed.

The fix is to clear the waiting_queue on shutdown of the nbd device, in
the same way that the nbd request queue (queue_head) is already being
cleared.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-17 15:00:37 -07:00
Linus Torvalds eff0d13f38 Merge branch 'for-3.6/drivers' of git://git.kernel.dk/linux-block
Pull block driver changes from Jens Axboe:

 - Making the plugging support for drivers a bit more sane from Neil.
   This supersedes the plugging change from Shaohua as well.

 - The usual round of drbd updates.

 - Using a tail add instead of a head add in the request completion for
   ndb, making us find the most completed request more quickly.

 - A few floppy changes, getting rid of a duplicated flag and also
   running the floppy init async (since it takes forever in boot terms)
   from Andi.

* 'for-3.6/drivers' of git://git.kernel.dk/linux-block:
  floppy: remove duplicated flag FD_RAW_NEED_DISK
  blk: pass from_schedule to non-request unplug functions.
  block: stack unplug
  blk: centralize non-request unplug handling.
  md: remove plug_cnt feature of plugging.
  block/nbd: micro-optimization in nbd request completion
  drbd: announce FLUSH/FUA capability to upper layers
  drbd: fix max_bio_size to be unsigned
  drbd: flush drbd work queue before invalidate/invalidate remote
  drbd: fix potential access after free
  drbd: call local-io-error handler early
  drbd: do not reset rs_pending_cnt too early
  drbd: reset congestion information before reporting it in /proc/drbd
  drbd: report congestion if we are waiting for some userland callback
  drbd: differentiate between normal and forced detach
  drbd: cleanup, remove two unused global flags
  floppy: Run floppy initialization asynchronous
2012-08-01 09:06:47 -07:00
Mel Gorman 7f338fe454 nbd: set SOCK_MEMALLOC for access to PFMEMALLOC reserves
Set SOCK_MEMALLOC on the NBD socket to allow access to PFMEMALLOC reserves
so pages backed by NBD, particularly if swap related, can be cleaned to
prevent the machine being deadlocked.  It is still possible that the
PFMEMALLOC reserves get depleted resulting in deadlock but this can be
resolved by the administrator by increasing min_free_kbytes.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: David Miller <davem@davemloft.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: Eric B Munson <emunson@mgebm.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-31 18:42:46 -07:00
Chetan Loke 01ff5dbc09 block/nbd: micro-optimization in nbd request completion
Add in-flight cmds to the tail. That way while searching
(during request completion),we will always get a hit on the
first element.

Signed-off-by: Chetan Loke <loke.chetan@gmail.com>
Acked-by: Paul.Clements@steeleye.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-07-31 08:47:13 +02:00
Linus Torvalds 532bfc851a Merge branch 'akpm' (Andrew's patch-bomb)
Merge third batch of patches from Andrew Morton:
 - Some MM stragglers
 - core SMP library cleanups (on_each_cpu_mask)
 - Some IPI optimisations
 - kexec
 - kdump
 - IPMI
 - the radix-tree iterator work
 - various other misc bits.

 "That'll do for -rc1.  I still have ~10 patches for 3.4, will send
  those along when they've baked a little more."

* emailed from Andrew Morton <akpm@linux-foundation.org>: (35 commits)
  backlight: fix typo in tosa_lcd.c
  crc32: add help text for the algorithm select option
  mm: move hugepage test examples to tools/testing/selftests/vm
  mm: move slabinfo.c to tools/vm
  mm: move page-types.c from Documentation to tools/vm
  selftests/Makefile: make `run_tests' depend on `all'
  selftests: launch individual selftests from the main Makefile
  radix-tree: use iterators in find_get_pages* functions
  radix-tree: rewrite gang lookup using iterator
  radix-tree: introduce bit-optimized iterator
  fs/proc/namespaces.c: prevent crash when ns_entries[] is empty
  nbd: rename the nbd_device variable from lo to nbd
  pidns: add reboot_pid_ns() to handle the reboot syscall
  sysctl: use bitmap library functions
  ipmi: use locks on watchdog timeout set on reboot
  ipmi: simplify locking
  ipmi: fix message handling during panics
  ipmi: use a tasklet for handling received messages
  ipmi: increase KCS timeouts
  ipmi: decrease the IPMI message transaction time in interrupt mode
  ...
2012-03-28 17:19:28 -07:00
Wanlong Gao f4507164e7 nbd: rename the nbd_device variable from lo to nbd
rename the nbd_device variable from "lo" to "nbd", since "lo" is just a name
copied from loop.c.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28 17:14:37 -07:00
David Howells 9ffc93f203 Remove all #inclusions of asm/system.h
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`

Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-28 18:30:03 +01:00
Andrew Morton 548ef6cc26 nbd-replace-some-printk-with-dev_warn-and-dev_info-checkpatch-fixes
ERROR: code indent should use tabs where possible
#30: FILE: drivers/block/nbd.c:578:
+^I        dev_info(disk_to_dev(lo->disk), "NBD_DISCONNECT\n");$

total: 1 errors, 0 warnings, 35 lines checked

NOTE: whitespace errors detected, you may wish to use scripts/cleanpatch or
      scripts/cleanfile

./patches/nbd-replace-some-printk-with-dev_warn-and-dev_info.patch has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: WANG Cong <amwang@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-19 14:48:28 +02:00
WANG Cong 5eedf5415c nbd: replace some printk with dev_warn() and dev_info()
Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-19 14:48:28 +02:00
WANG Cong 7742ce4ab4 nbd: lower the loglevel of an error message
This is only an error, no need to use KERN_CRIT log level.

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-19 14:48:28 +02:00
WANG Cong 7f1b90f99a nbd: replace printk KERN_ERR with dev_err()
Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-19 14:48:22 +02:00
WANG Cong 1695b87f7d nbd: replace sysfs_create_file() with device_create_file()
Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-19 14:48:21 +02:00
WANG Cong 25ac0c2b97 nbd: use task_pid_nr() to get current pid
Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-08-19 14:48:17 +02:00
Namhyung Kim 5988ce2396 nbd: adjust 'max_part' according to part_shift
The 'max_part' parameter determines how many partitions are supported
on each nbd device. However the actual number can be changed to the
power of 2 minus 1 form during the module initialization as
alloc_disk() is called with (1 << part_shift) for some reason.

So adjust 'max_part' also at least for consistency with loop and brd.
It is exported via sysfs already, and a user should check this value
after module loading if [s]he wants to use that number correctly
(i.e. fdisk or something).

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-28 14:44:46 +02:00
Namhyung Kim 3b2710824e nbd: limit module parameters to a sane value
The 'max_part' parameter controls the number of maximum partition
a nbd 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 oops (or, at least, produce invalid device
nodes in some cases).

In addition, specifying large 'nbds_max' value causes same
problem for the same reason.

On my desktop, following command results to the kernel bug:

$ sudo modprobe nbd max_part=100000
 kernel BUG at /media/Linux_Data/project/linux/fs/sysfs/group.c:65!
 invalid opcode: 0000 [#1] SMP
 last sysfs file: /sys/devices/virtual/block/nbd4/range
 CPU 1
 Modules linked in: nbd(+) bridge stp llc kvm_intel kvm asus_atk0110 sg sr_mod cdrom

 Pid: 2522, comm: modprobe Tainted: G        W   2.6.39-leonard+ #159 System manufacturer System Product Name/P5G41TD-M PRO
 RIP: 0010:[<ffffffff8115aa08>]  [<ffffffff8115aa08>] internal_create_group+0x2f/0x166
 RSP: 0018:ffff8801009f1de8  EFLAGS: 00010246
 RAX: 00000000ffffffef RBX: ffff880103920478 RCX: 00000000000a7bd3
 RDX: ffffffff81a2dbe0 RSI: 0000000000000000 RDI: ffff880103920478
 RBP: ffff8801009f1e38 R08: ffff880103920468 R09: ffff880103920478
 R10: ffff8801009f1de8 R11: ffff88011eccbb68 R12: ffffffff81a2dbe0
 R13: ffff880103920468 R14: 0000000000000000 R15: ffff880103920400
 FS:  00007f3c49de9700(0000) GS:ffff88011f800000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 00007f3b7fe7c000 CR3: 00000000cd58d000 CR4: 00000000000406e0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Process modprobe (pid: 2522, threadinfo ffff8801009f0000, task ffff8801009a93a0)
 Stack:
  ffff8801009f1e58 ffffffff812e8f6e ffff8801009f1e58 ffffffff812e7a80
  ffff880000000010 ffff880103920400 ffff8801002fd0c0 ffff880103920468
  0000000000000011 ffff880103920400 ffff8801009f1e48 ffffffff8115ab6a
 Call Trace:
  [<ffffffff812e8f6e>] ? device_add+0x4f1/0x5e4
  [<ffffffff812e7a80>] ? dev_set_name+0x41/0x43
  [<ffffffff8115ab6a>] sysfs_create_group+0x13/0x15
  [<ffffffff810b857e>] blk_trace_init_sysfs+0x14/0x16
  [<ffffffff811ee58b>] blk_register_queue+0x4c/0xfd
  [<ffffffff811f3bdf>] add_disk+0xe4/0x29c
  [<ffffffffa007e2ab>] nbd_init+0x2ab/0x30d [nbd]
  [<ffffffffa007e000>] ? 0xffffffffa007dfff
  [<ffffffff8100020f>] do_one_initcall+0x7f/0x13e
  [<ffffffff8107ab0a>] sys_init_module+0xa1/0x1e3
  [<ffffffff814f3542>] system_call_fastpath+0x16/0x1b
 Code: 41 57 41 56 41 55 41 54 53 48 83 ec 28 0f 1f 44 00 00 48 89 fb 41 89 f6 49 89 d4 48 85 ff 74 0b 85 f6 75 0b 48 83
  7f 30 00 75 14 <0f> 0b eb fe b9 ea ff ff ff 48 83 7f 30 00 0f 84 09 01 00 00 49
 RIP  [<ffffffff8115aa08>] internal_create_group+0x2f/0x166
  RSP <ffff8801009f1de8>
 ---[ end trace 753285ffbf72c57c ]---

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Laurent Vivier <Laurent.Vivier@bull.net>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: stable@kernel.org
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-28 14:44:46 +02:00
Namhyung Kim 35fbf5bcf4 nbd: pass MSG_* flags to kernel_recvmsg()
Unlike kernel_sendmsg(), kernel_recvmsg() requires passing flags explicitly
via last parameter instead of struct msghdr.msg_flags. Therefore calls to
sock_xmit(lo, 0, ..., MSG_WAITALL) have not been processed properly by tcp
layer wrt. the flag. Fix it.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-05-28 14:44:46 +02:00
Soren Hansen de1f016f88 nbd: remove module-level ioctl mutex
Commit 2a48fc0ab2 ("block: autoconvert trivial BKL users to private
mutex") replaced uses of the BKL in the nbd driver with mutex
operations.  Since then, I've been been seeing these lock ups:

 INFO: task qemu-nbd:16115 blocked for more than 120 seconds.
 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
 qemu-nbd      D 0000000000000001     0 16115  16114 0x00000004
  ffff88007d775d98 0000000000000082 ffff88007d775fd8 ffff88007d774000
  0000000000013a80 ffff8800020347e0 ffff88007d775fd8 0000000000013a80
  ffff880133730000 ffff880002034440 ffffea0004333db8 ffffffffa071c020
 Call Trace:
  [<ffffffff815b9997>] __mutex_lock_slowpath+0xf7/0x180
  [<ffffffff815b93eb>] mutex_lock+0x2b/0x50
  [<ffffffffa071a21c>] nbd_ioctl+0x6c/0x1c0 [nbd]
  [<ffffffff812cb970>] blkdev_ioctl+0x230/0x730
  [<ffffffff811967a1>] block_ioctl+0x41/0x50
  [<ffffffff81175c03>] do_vfs_ioctl+0x93/0x370
  [<ffffffff81175f61>] sys_ioctl+0x81/0xa0
  [<ffffffff8100c0c2>] system_call_fastpath+0x16/0x1b

Instrumenting the nbd module's ioctl handler with some extra logging
clearly shows the NBD_DO_IT ioctl being invoked which is a long-lived
ioctl in the sense that it doesn't return until another ioctl asks the
driver to disconnect.  However, that other ioctl blocks, waiting for the
module-level mutex that replaced the BKL, and then we're stuck.

This patch removes the module-level mutex altogether.  It's clearly
wrong, and as far as I can see, it's entirely unnecessary, since the nbd
driver maintains per-device mutexes, and I don't see anything that would
require a module-level (or kernel-level, for that matter) mutex.

Signed-off-by: Soren Hansen <soren@linux2go.dk>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@kernel.org>		[2.6.37.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-11 16:12:20 -08:00
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
Linus Torvalds 2f9e825d3e Merge branch 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
  block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
  xen-blkfront: fix missing out label
  blkdev: fix blkdev_issue_zeroout return value
  block: update request stacking methods to support discards
  block: fix missing export of blk_types.h
  writeback: fix bad _bh spinlock nesting
  drbd: revert "delay probes", feature is being re-implemented differently
  drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
  drbd: Disable delay probes for the upcomming release
  writeback: cleanup bdi_register
  writeback: add new tracepoints
  writeback: remove unnecessary init_timer call
  writeback: optimize periodic bdi thread wakeups
  writeback: prevent unnecessary bdi threads wakeups
  writeback: move bdi threads exiting logic to the forker thread
  writeback: restructure bdi forker loop a little
  writeback: move last_active to bdi
  writeback: do not remove bdi from bdi_list
  writeback: simplify bdi code a little
  writeback: do not lose wake-ups in bdi threads
  ...

Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.
2010-08-10 15:22:42 -07:00
Arnd Bergmann 8a6cfeb6de block: push down BKL into .locked_ioctl
As a preparation for the removal of the big kernel
lock in the block layer, this removes the BKL
from the common ioctl handling code, moving it
into every single driver still using it.

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 18:25:00 +02:00
Christoph Hellwig 33659ebbae block: remove wrappers for request type/flags
Remove all the trivial wrappers for the cmd_type and cmd_flags fields in
struct requests.  This allows much easier grepping for different request
types instead of unwinding through macros.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:17:56 +02:00
Pavel Machek a2531293db update email address
pavel@suse.cz no longer works, replace it with working address.

Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-07-19 10:56:54 +02:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
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>
2010-03-30 22:02:32 +09:00
Alexey Dobriyan 83d5cde47d const: make block_device_operations const
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-22 07:17:25 -07:00
Tejun Heo 9934c8c045 block: implement and enforce request peek/start/fetch
Till now block layer allowed two separate modes of request execution.
A request is always acquired from the request queue via
elv_next_request().  After that, drivers are free to either dequeue it
or process it without dequeueing.  Dequeue allows elv_next_request()
to return the next request so that multiple requests can be in flight.

Executing requests without dequeueing has its merits mostly in
allowing drivers for simpler devices which can't do sg to deal with
segments only without considering request boundary.  However, the
benefit this brings is dubious and declining while the cost of the API
ambiguity is increasing.  Segment based drivers are usually for very
old or limited devices and as converting to dequeueing model isn't
difficult, it doesn't justify the API overhead it puts on block layer
and its more modern users.

Previous patches converted all block low level drivers to dequeueing
model.  This patch completes the API transition by...

* renaming elv_next_request() to blk_peek_request()

* renaming blkdev_dequeue_request() to blk_start_request()

* adding blk_fetch_request() which is combination of peek and start

* disallowing completion of queued (not started) requests

* applying new API to all LLDs

Renamings are for consistency and to break out of tree code so that
it's apparent that out of tree drivers need updating.

[ Impact: block request issue API cleanup, no functional change ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: unsik Kim <donari75@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Laurent Vivier <Laurent@lvivier.info>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:52:18 +02:00
Tejun Heo 1011c1b9f2 block: blk_rq_[cur_]_{sectors|bytes}() usage cleanup
With the previous changes, the followings are now guaranteed for all
requests in any valid state.

* blk_rq_sectors() == blk_rq_bytes() >> 9
* blk_rq_cur_sectors() == blk_rq_cur_bytes() >> 9

Clean up accessor usages.  Notable changes are

* nbd,i2o_block: end_all used instead of explicit byte count
* scsi_lib: unnecessary conditional on request type removed

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:55 +02:00
Tejun Heo 83096ebf12 block: convert to pos and nr_sectors accessors
With recent cleanups, there is no place where low level driver
directly manipulates request fields.  This means that the 'hard'
request fields always equal the !hard fields.  Convert all
rq->sectors, nr_sectors and current_nr_sectors references to
accessors.

While at it, drop superflous blk_rq_pos() < 0 test in swim.c.

[ Impact: use pos and nr_sectors accessors ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Mike Miller <mike.miller@hp.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Dario Ballabio <ballabio_dario@emc.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: unsik Kim <donari75@gmail.com>
Cc: Laurent Vivier <Laurent@lvivier.info>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:54 +02:00
Tejun Heo 53d6979ab6 nbd: don't clear rq->sector and nr_sectors unnecessarily
There's no reason to clear rq->sector and nr_sectors after calling
blk_rq_init().  They're guaranteed to be clear.  Drop unnecessary
clearing.

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:53 +02:00
Pavel Machek 15746fcaa3 nbd: trivial cleanups
Trivial cleanups for nbd: only the return -EIO one really changes code,
and I've verified all the callers (plus 0 == success, 1 == error
convention is really ugly).

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:05:02 -07:00
Pavel Machek 1a2ad21128 nbd: add locking to nbd_ioctl
The code was written to rely on big kernel lock to protect it from races.
It mostly works when interface is not abused.

So this uses tx_lock to protect data structures from concurrent use
between ioctl and worker threads.

Next step will be moving from ioctl to unlocked_ioctl.

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: add missing return]
Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02 19:05:02 -07:00
Paul Clements 4d48a542b4 nbd: fix I/O hang on disconnected nbds
Fix a problem that causes I/O to a disconnected (or partially initialized)
nbd device to hang indefinitely.  To reproduce:

# ioctl NBD_SET_SIZE_BLOCKS /dev/nbd23 514048
# dd if=/dev/nbd23 of=/dev/null bs=4096 count=1

...hangs...

This can also occur when an nbd device loses its nbd-client/server
connection.  Although we clear the queue of any outstanding I/Os after the
client/server connection fails, any additional I/Os that get queued later
will hang.

This bug may also be the problem reported in this bug report:
http://bugzilla.kernel.org/show_bug.cgi?id=12277

Testing would need to be performed to determine if the two issues are the
same.

This problem was introduced by the new request handling thread code ("NBD:
allow nbd to be used locally", 3/2008), which entered into mainline around
2.6.25.

The fix, which is fairly simple, is to restore the check for lo->sock
being NULL in do_nbd_request.  This causes I/O to an uninitialized nbd to
immediately fail with an I/O error, as it did prior to the introduction of
this bug.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Reported-by: Jon Nelson <jnelson-kernel-bugzilla@jamponi.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: <stable@kernel.org>		[2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-11 14:25:37 -08:00
Pavel Machek c91192d66d nbd: do not allow two clients at the same time
Two nbd-clients at same time are bad idea, and cause WARN_ON from nbd in
2.6.28-rc7 from sysfs_add_one.  This simply prevents that from happening.

To reproduce:

 cat /dev/zero | head -c 10000000 > /tmp/delme.fstest.fs
 nbd-server 9100 -l /anyone.can.connect > /tmp/delme.fstest.fs &
 sleep 1
 nbd-client localhost 9100 /dev/nd0 &
 nbd-client localhost 9100 /dev/nd0 &

Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-15 16:39:38 -08:00
Jens Axboe 31dcfab0ae nbd: tell the block layer that it is not a rotational device
Then we can get rid of that manual elevator type fiddling.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:29:50 +01:00
Jens Axboe b374d18a4b block: get rid of elevator_t typedef
Just use struct elevator_queue everywhere instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:29:50 +01:00
Al Viro a8cdc308c0 [PATCH] switch nbd
NB: nbd_ioctl() appears to be racy; BKL is held, but doesn't really
help, AFAICS.  Left as-is for now, but it'll need fixing.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:53 -04:00
Al Viro d4430d62fa [PATCH] beginning of methods conversion
To keep the size of changesets sane we split the switch by drivers;
to keep the damn thing bisectable we do the following:
	1) rename the affected methods, add ones with correct
prototypes, make (few) callers handle both.  That's this changeset.
	2) for each driver convert to new methods.  *ALL* drivers
are converted in this series.
	3) kill the old (renamed) methods.

Note that it _is_ a flagday; all in-tree drivers are converted and by the
end of this series no trace of old methods remain.  The only reason why
we do that this way is to keep the damn thing bisectable and allow per-driver
debugging if anything goes wrong.

New methods:
	open(bdev, mode)
	release(disk, mode)
	ioctl(bdev, mode, cmd, arg)		/* Called without BKL */
	compat_ioctl(bdev, mode, cmd, arg)
	locked_ioctl(bdev, mode, cmd, arg)	/* Called with BKL, legacy */

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:47:32 -04:00
Parag Warudkar 01e8ef11bc x86: sysfs: kill owner field from attribute
Tejun's commit 7b595756ec made sysfs
attribute->owner unnecessary.  But the field was left in the structure to
ease the merge.  It's been over a year since that change and it is now
time to start killing attribute->owner along with its users - one arch at
a time!

This patch is attempt #1 to get rid of attribute->owner only for
CONFIG_X86_64 or CONFIG_X86_32 .  We will deal with other arches later on
as and when possible - avr32 will be the next since that is something I
can test.  Compile (make allyesconfig / make allmodconfig / custom config)
and boot tested.

akpm: the idea is that we put the declaration of sttribute.owner inside
`#ifndef CONFIG_X86'.  But that proved to be too ambitious for now because
new usages kept on turning up in subsystem trees.

[akpm: remove the ifdef for now]
Signed-off-by: Parag Warudkar <parag.lkml@gmail.com>
Cc: Greg KH <greg@kroah.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:42 -07:00
Tejun Heo ed9e198234 block: implement and use {disk|part}_to_dev()
Implement {disk|part}_to_dev() and use them to access generic device
instead of directly dereferencing {disk|part}->dev.  To make sure no
user is left behind, rename generic devices fields to __dev.

This is in preparation of unifying partition 0 handling with other
partitions.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:07 +02:00
Sven Wegener f3944d61dd nbd: fix memory leak of nbd_dev array
We leak the memory allocated for the nbd_dev array at multiple places.
Fix them by either adding a kfree() or by rearranging code to return
before we allocate the memory.

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-20 15:40:30 -07:00
Linus Torvalds bd5d435a96 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: Skip I/O merges when disabled
  block: add large command support
  block: replace sizeof(rq->cmd) with BLK_MAX_CDB
  ide: use blk_rq_init() to initialize the request
  block: use blk_rq_init() to initialize the request
  block: rename and export rq_init()
  block: no need to initialize rq->cmd with blk_get_request
  block: no need to initialize rq->cmd in prepare_flush_fn hook
  block/blk-barrier.c:blk_ordered_cur_seq() mustn't be inline
  block/elevator.c:elv_rq_merge_ok() mustn't be inline
  block: make queue flags non-atomic
  block: add dma alignment and padding support to blk_rq_map_kern
  unexport blk_max_pfn
  ps3disk: Remove superfluous cast
  block: make rq_init() do a full memset()
  relay: fix splice problem
2008-04-29 08:18:03 -07:00
Hirofumi Nakagawa 801678c5a3 Remove duplicated unlikely() in IS_ERR()
Some drivers have duplicated unlikely() macros.  IS_ERR() already has
unlikely() in itself.

This patch cleans up such pointless code.

Signed-off-by: Hirofumi Nakagawa <hnakagawa@miraclelinux.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jeff Garzik <jeff@garzik.org>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:25 -07:00
Laurent Vivier d71a6d7332 NBD: add partition support
Permit the use of partitions with network block devices (NBD).

A new parameter is introduced to define how many partition we want to be able
to manage per network block device.  This parameter is "max_part".

For instance, to manage 63 partitions / loop device, we will do:

   [on the server side]
# nbd-server 1234 /dev/sdb
   [on the client side]
# modprobe nbd max_part=63
# ls -l /dev/nbd*
brw-rw---- 1 root disk 43,   0 2008-03-25 11:14 /dev/nbd0
brw-rw---- 1 root disk 43,  64 2008-03-25 11:11 /dev/nbd1
brw-rw---- 1 root disk 43, 640 2008-03-25 11:11 /dev/nbd10
brw-rw---- 1 root disk 43, 704 2008-03-25 11:11 /dev/nbd11
brw-rw---- 1 root disk 43, 768 2008-03-25 11:11 /dev/nbd12
brw-rw---- 1 root disk 43, 832 2008-03-25 11:11 /dev/nbd13
brw-rw---- 1 root disk 43, 896 2008-03-25 11:11 /dev/nbd14
brw-rw---- 1 root disk 43, 960 2008-03-25 11:11 /dev/nbd15
brw-rw---- 1 root disk 43, 128 2008-03-25 11:11 /dev/nbd2
brw-rw---- 1 root disk 43, 192 2008-03-25 11:11 /dev/nbd3
brw-rw---- 1 root disk 43, 256 2008-03-25 11:11 /dev/nbd4
brw-rw---- 1 root disk 43, 320 2008-03-25 11:11 /dev/nbd5
brw-rw---- 1 root disk 43, 384 2008-03-25 11:11 /dev/nbd6
brw-rw---- 1 root disk 43, 448 2008-03-25 11:11 /dev/nbd7
brw-rw---- 1 root disk 43, 512 2008-03-25 11:11 /dev/nbd8
brw-rw---- 1 root disk 43, 576 2008-03-25 11:11 /dev/nbd9
# nbd-client localhost 1234 /dev/nbd0
Negotiation: ..size = 80418240KB
bs=1024, sz=80418240

-------NOTE, RFC: partition table is not automatically read.
The driver sets bdev->bd_invalidated to 1 to force the read of the partition
table of the device, but this is done only on an open of the device.
So we have to do a "touch /dev/nbdX" or something like that.
It can't be done from the nbd-client or nbd driver because at this
level we can't ask to read the partition table and to serve the request
at the same time (-> deadlock)

If someone has a better idea, I'm open to any suggestion.
-------NOTE, RFC

# fdisk -l /dev/nbd0

Disk /dev/nbd0: 82.3 GB, 82348277760 bytes
255 heads, 63 sectors/track, 10011 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

     Device Boot      Start         End      Blocks   Id  System
/dev/nbd0p1   *           1        9965    80043831   83  Linux
/dev/nbd0p2            9966       10011      369495    5  Extended
/dev/nbd0p5            9966       10011      369463+  82  Linux swap / Solaris

# ls -l /dev/nbd0*
brw-rw---- 1 root disk 43,   0 2008-03-25 11:16 /dev/nbd0
brw-rw---- 1 root disk 43,   1 2008-03-25 11:16 /dev/nbd0p1
brw-rw---- 1 root disk 43,   2 2008-03-25 11:16 /dev/nbd0p2
brw-rw---- 1 root disk 43,   5 2008-03-25 11:16 /dev/nbd0p5
# mount /dev/nbd0p1 /mnt
# ls /mnt
bin    dev   initrd      lost+found  opt   sbin     sys  var
boot   etc   initrd.img  media       proc  selinux  tmp  vmlinuz
cdrom  home  lib         mnt         root  srv      usr
# umount /mnt
# nbd-client -d /dev/nbd0
# ls -l /dev/nbd0*
brw-rw---- 1 root disk 43, 0 2008-03-25 11:16 /dev/nbd0
-------NOTE
On "nbd-client -d", we can do an iocl(BLKRRPART) to update partition table:
as the size of the device is 0, we don't have to serve the partition manager
request (-> no deadlock).
-------NOTE

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:23 -07:00
Laurent Vivier 48cf6061b3 NBD: allow nbd to be used locally
This patch allows Network Block Device to be mounted locally (nbd-client to
nbd-server over 127.0.0.1).

It creates a kthread to avoid the deadlock described in NBD tools
documentation.  So, if nbd-client hangs waiting for pages, the kblockd thread
can continue its work and free pages.

I have tested the patch to verify that it avoids the hang that always occurs
when writing to a localhost nbd connection.  I have also tested to verify that
no performance degradation results from the additional thread and queue.

Patch originally from Laurent Vivier.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:23 -07:00
FUJITA Tomonori 4f54eec831 block: use blk_rq_init() to initialize the request
Any path needs to call it to initialize the request.

This is a preparation for large command support, which needs to
initialize the request in a proper way (that is, just doing a memset()
will not work).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-04-29 14:48:55 +02:00
Mike Snitzer ffc41cf8db nbd: prevent sock_xmit from attempting to use a NULL socket
NBD does not protect the nbd_device's socket from becoming NULL during
receives.

This closes a race with the NBD_CLEAR_SOCK ioctl (nbd-client -d) setting
the nbd_device's socket to NULL right before NBD calls sock_xmit.

Signed-off-by: Mike Snitzer <snitzer@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-02 15:28:19 -07:00
Paul Clements 48f15b93b2 NBD: make nbd default to deadline I/O scheduler
NBD doesn't work well with CFQ (or AS) schedulers, so let's default to
something else.

The two problems I have experienced with nbd and cfq are:

1) nbd hangs with cfq on RHEL 5 (2.6.18) -- this may well have been
   fixed

   There's a similar debian bug that has been filed as well:

   http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=447638

   There have been posts to nbd-general mailing list about problems with
   cfq and nbd also.

2) nbd performs about 10% better (the last time I tested) with deadline
   vs.  cfq (the overhead of cfq doesn't provide much advantage to nbd [not
   being a real disk], and you end up going through the I/O scheduler on
   the nbd server anyway, so it makes sense that deadline is better with
   nbd)

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-23 17:12:15 -08:00
Paul Clements 20a8143eaa NBD: remove limit on max number of nbd devices
Remove the arbitrary 128 device limit for NBD.  nbds_max can now be set to
any number.  In certain scenarios where devices are used sparsely we have
run into the 128 device limit.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08 09:22:41 -08:00
Kiyoshi Ueda 097c94a4e8 blk_end_request: changing nbd (take 4)
This patch converts nbd to use blk_end_request interfaces.
Related 'uptodate' arguments are converted to 'error'.

Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-01-28 10:36:37 +01:00
Kay Sievers edfaa7c365 Driver core: convert block from raw kobjects to core devices
This moves the block devices to /sys/class/block. It will create a
flat list of all block devices, with the disks and partitions in one
directory. For compatibility /sys/block is created and contains symlinks
to the disks.

  /sys/class/block
  |-- sda -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda
  |-- sda1 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1
  |-- sda10 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda10
  |-- sda5 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5
  |-- sda6 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda6
  |-- sda7 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda7
  |-- sda8 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda8
  |-- sda9 -> ../../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda9
  `-- sr0 -> ../../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0

  /sys/block/
  |-- sda -> ../devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda
  `-- sr0 -> ../devices/pci0000:00/0000:00:1f.2/host1/target1:0:0/1:0:0:0/block/sr0

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24 20:40:36 -08:00
Trond Myklebust 91cf45f02a [NET]: Add the helper kernel_sock_shutdown()
...and fix a couple of bugs in the NBD, CIFS and OCFS2 socket handlers.

Looking at the sock->op->shutdown() handlers, it looks as if all of them
take a SHUT_RD/SHUT_WR/SHUT_RDWR argument instead of the
RCV_SHUTDOWN/SEND_SHUTDOWN arguments.
Add a helper, and then define the SHUT_* enum to ensure that kernel users
of shutdown() don't get confused.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Mark Fasheh <mark.fasheh@oracle.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-12 18:10:39 -08:00
Denis Cheng d489202ea2 remove unused return within void return function
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
2007-10-20 02:18:21 +02:00
Pavel Emelyanov ba25f9dcc4 Use helpers to obtain task pid in printks
The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.

The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.

[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:43 -07:00
Paul Clements 7fdfd4065c NBD: allow hung network I/O to be cancelled
Allow NBD I/O to be cancelled when a network outage occurs.  Previously, I/O
would just hang, and if enough I/O was hung in nbd, the system (at least
user-level) would completely hang until a TCP timeout (default, 15 minutes)
occurred.

The patch introduces a new ioctl NBD_SET_TIMEOUT that allows a transmit
timeout value (in seconds) to be specified.  Any network send that exceeds the
timeout will be cancelled and the nbd connection will be shut down.  I've
tested with various timeout values and 6 seconds seems to be a good choice for
the timeout.  If the NBD_SET_TIMEOUT ioctl is not called, you get the old (I/O
hang) behavior.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:55 -07:00
Paul Clements 4b86a87256 NBD: set uninitialized devices to size 0
This fixes errors with utilities (such as LVM's vgscan) that try to scan all
devices.  Previously this would generate read errors when uninitialized nbd
devices were scanned:

# vgscan
   Reading all physical volumes.  This may take a while...
   /dev/nbd0: read failed after 0 of 1024 at 0: Input/output error
   /dev/nbd0: read failed after 0 of 1024 at 509804544: Input/output error
   /dev/nbd0: read failed after 0 of 2048 at 0: Input/output error
   /dev/nbd1: read failed after 0 of 1024 at 509804544: Input/output error
   /dev/nbd1: read failed after 0 of 2048 at 0: Input/output error

 From now on, uninitialized nbd devices will have size zero, which
prevents these errors.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:55 -07:00
Denis Cheng 0cbc591bf8 nbd: change a parameter's type to remove a memcpy call
This memcpy looks so strange, in fact it's merely a pointer dereference, so I
change the parameter's type to refer it more directly, this could make the
memcpy not needed anymore.

In the function nbd_read_stat where nbd_find_request is only once called, the
parameter served should be transformed accordingly.

Signed-off-by: Denis Cheng <crquan@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:47 -07:00
Denis Cheng d2c9740b49 nbd: use list_for_each_entry_safe to make it more consolidated and readable
Thus the traverse of the loop may delete nodes, use the safe version.

Signed-off-by: Denis Cheng <crquan@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:47 -07:00
Jens Axboe 6c92e699b5 Fixup rq_for_each_segment() indentation
Remove one level of nesting where appropriate.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:56 +02:00
NeilBrown 5705f70217 Introduce rq_for_each_segment replacing rq_for_each_bio
Every usage of rq_for_each_bio wraps a usage of
bio_for_each_segment, so these can be combined into
rq_for_each_segment.

We define "struct req_iterator" to hold the 'bio' and 'index' that
are needed for the double iteration.

Signed-off-by: Neil Brown <neilb@suse.de>

Various compile fixes by me...

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-10 09:25:56 +02:00
Jens Axboe 165125e1e4 [BLOCK] Get rid of request_queue_t typedef
Some of the code has been gradually transitioned to using the proper
struct request_queue, but there's lots left. So do a full sweet of
the kernel and get rid of this typedef and replace its uses with
the proper type.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-24 09:28:11 +02:00
Oleg Nesterov be0ef957c9 nbd.c: sock_xmit: cleanup signal related code
sock_xmit() re-implements sigprocmask() and dequeue_signal_lock().

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:50 -07:00
Boaz Harrosh e654bc4393 [PATCH] fix request->cmd == INT cases
- I have unearthed very old bugs in stale drivers that still
   used request->cmd as a READ|WRITE int
 - This patch is maybe a proof that these drivers have not been
   used for a long time. Should they be removed completely?

Drivers that currently do not work for sure:
 drivers/acorn/block/fd1772.c |    2 +-
 drivers/acorn/block/mfmhd.c  |    8 ++++----
 drivers/cdrom/aztcd.c        |    2 +-
 drivers/cdrom/cm206.c        |    2 +-
 drivers/cdrom/gscd.c         |    2 +-
 drivers/cdrom/mcdx.c         |    2 +-
 drivers/cdrom/optcd.c        |    2 +-
 drivers/cdrom/sjcd.c         |    2 +-

Drivers with cosmetic fixes only:
  b/drivers/block/amiflop.c
  b/drivers/block/nbd.c
  b/drivers/ide/legacy/hd.c

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-07-10 08:03:34 +02:00
WANG Cong 84963048ca nbd: check the return value of sysfs_create_file
[akpm@linux-foundation.org: fix it]
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:49 -07:00
Josef Sipek 17506041de [PATCH] struct path: convert nbd
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:47 -08:00
Paul Clements 6b39bb6548 [PATCH] nbd: show nbd client pid in sysfs
Allow nbd to expose the nbd-client daemon's PID in /sys/block/nbd<x>/pid.

This is helpful for tracking connection status of a device and for
determining which nbd devices are currently in use.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:47 -08:00
Jens Axboe 4aff5e2333 [PATCH] Split struct request ->flags into two parts
Right now ->flags is a bit of a mess: some are request types, and
others are just modifiers. Clean this up by splitting it into
->cmd_type and ->cmd_flags. This allows introduction of generic
Linux block message types, useful for sending generic Linux commands
to block devices.

Signed-off-by: Jens Axboe <axboe@suse.de>
2006-09-30 20:23:37 +02:00
Michal Feix f0df33bcab [PATCH] nbd: Abort request on data reception failure
When reading from nbd device, we need to receive all the data after
receiving reply packet from the server - otherwise such request will never
be ended.

If socket is closed right after accepting reply control packet and in the
middle of waiting for read data, nbd_read_stat() returns NULL and
nbd_end_request() is not called.

This patch fixes it.

Signed-off-by: Michal Feix <michal@feix.cz>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-31 13:28:39 -07:00
Michal Feix e4b57e0842 [PATCH] nbd: Check magic before doing anything else
We should check magic sequence in reply packet before trying to find
request with it's request handle.  This also solves the problem with
"Unexpected reply" message beeing logged, when packet with invalid magic is
received.

Signed-off-by: Michal Feix <michal@feix.cz>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-31 13:28:39 -07:00
Ingo van Lil 9c7a41691f [PATCH] drivers/block/nbd.c compile fix
The Network Block Device driver doesn't compile if NDEBUG is defined.

Signed-off-by: Ingo van Lil <inguin@gmx.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-01 09:56:04 -07:00
Greg Kroah-Hartman ce7b0f46bb [PATCH] devfs: Remove the gendisk devfs_name field as it's no longer needed
And remove the now unneeded number field.
Also fixes all drivers that set these fields.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:08 -07:00
Greg Kroah-Hartman ff23eca3e8 [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
Also fixes up all files that #include it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:08 -07:00
Greg Kroah-Hartman 8ab5e4c15b [PATCH] devfs: Remove devfs_remove() function from the kernel tree
Removes the devfs_remove() function and all callers of it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:07 -07:00
Greg Kroah-Hartman 95dc112a57 [PATCH] devfs: Remove devfs_mk_dir() function from the kernel tree
Removes the devfs_mk_dir() function and all callers of it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:06 -07:00