According to the tests in do_initcalls(), the proper error code in case no
device is found is -ENODEV, not -ENXIO or -EIO.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The code that needed this #include was removed one year ago.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: rmk@arm.linux.org.uk
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Many people will see this option the first time now that it is in
drivers/block/
Make it clear that virtually noone needs it.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: rmk@arm.linux.org.uk
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This patch moves hd.c to drivers/block/
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: rmk@arm.linux.org.uk
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6: (80 commits)
ide-floppy: fix unfortunate function naming
ide-tape: unify idetape_create_read/write_cmd
ide: add ide_pc_intr() helper
ide-{floppy,scsi}: read Status Register before stopping DMA engine
ide-scsi: add more debugging to idescsi_pc_intr()
ide-scsi: use pc->callback
ide-floppy: add more debugging to idefloppy_pc_intr()
ide-tape: always log debug info in idetape_pc_intr() if debugging is enabled
ide-tape: add ide_tape_io_buffers() helper
ide-tape: factor out DSC handling from idetape_pc_intr()
ide-{floppy,tape}: move checking of ->failed_pc to ->callback
ide: add ide_issue_pc() helper
ide: add PC_FLAG_DRQ_INTERRUPT pc flag
ide-scsi: move idescsi_map_sg() call out from idescsi_issue_pc()
ide: add ide_transfer_pc() helper
ide-scsi: set drive->scsi flag for devices handled by the driver
ide-{cd,floppy,tape}: remove checking for drive->scsi
ide: add PC_FLAG_ZIP_DRIVE pc flag
ide-tape: factor out waiting for good ireason from idetape_transfer_pc()
ide-tape: set PC_FLAG_DMA_IN_PROGRESS flag in idetape_transfer_pc()
...
pd_special_command uses blk_put_request with struct request on the
stack. As a result, blk_put_request needs a hack to catch a NULL
request_queue. This converts pd_special_command to use
blk_execute_rq.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (37 commits)
splice: fix generic_file_splice_read() race with page invalidation
ramfs: enable splice write
drivers/block/pktcdvd.c: avoid useless memset
cdrom: revert commit 22a9189 (cdrom: use kmalloced buffers instead of buffers on stack)
scsi: sr avoids useless buffer allocation
block: blk_rq_map_kern uses the bounce buffers for stack buffers
block: add blk_queue_update_dma_pad
DAC960: push down BKL
pktcdvd: push BKL down into driver
paride: push ioctl down into driver
block: use get_unaligned_* helpers
block: extend queue_flag bitops
block: request_module(): use format string
Add bvec_merge_data to handle stacked devices and ->merge_bvec()
block: integrity flags can't use bit ops on unsigned short
cmdfilter: extend default read filter
sg: fix odd style (extra parenthesis) introduced by cmd filter patch
block: add bounce support to blk_rq_map_user_iov
cfq-iosched: get rid of enable_idle being unused warning
allow userspace to modify scsi command filter on per device basis
...
This patch changes the way we determine the maximum number of outstanding
commands for each controller.
Most Smart Array controllers can support up to 1024 commands, the notable
exceptions are the E200 and E200i.
The next generation of controllers which were just added support a mode of
operation called Zero Memory Raid (ZMR). In this mode they only support
64 outstanding commands. In Full Function Raid (FFR) mode they support
1024.
We have been setting the queue depth by arbitrarily assigning some value
for each controller. We needed a better way to set the queue depth to
avoid lots of annoying "fifo full" messages. So we made the driver a
little smarter. We now read the config table and subtract 4 from the
returned value. The -4 is to allow some room for ioctl calls which are
not tracked the same way as io commands are tracked.
Please consider this for inclusion.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix regression in cciss driver that if no logical drives are configured,
no device nodes at all get created.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cca.cpqcorp.net>
Acked-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Avoid the 'memset(...,0, ...)' before calling 'init_cdrom_command' because
this function already does it.
Signed-off-by: Christophe Jaillet <jaillet.christophe@wanadoo.fr>
Acked-by: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Push the lock_kernel down into the driver and switch to unlocked_ioctl
[akpm@linux-foundation.org: build fix]
Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Leaves us with lock_kernel for two methods. Also remove a bogus printk
with no printk level and return -ENOTTY not -EINVAL for correctness.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(Jens: added smp_lock.h include to pt.c, otherwise it wont compile because
of missing {un}lock_kernel() definition)
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
When devices are stacked, one device's merge_bvec_fn may need to perform
the mapping and then call one or more functions for its underlying devices.
The following bio fields are used:
bio->bi_sector
bio->bi_bdev
bio->bi_size
bio->bi_rw using bio_data_dir()
This patch creates a new struct bvec_merge_data holding a copy of those
fields to avoid having to change them directly in the struct bio when
going down the stack only to have to change them back again on the way
back up. (And then when the bio gets mapped for real, the whole
exercise gets repeated, but that's a problem for another day...)
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Milan Broz <mbroz@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Avoid allocations causing swap activity on the resume path by
preventing the allocations from doing IO and allowing them
to access the emergency pools.
These paths are used when a frontend device is trying to connect
to its backend driver over Xenbus. These reconnections are triggered
on demand by IO, so by definition there is already IO underway,
and further IO would naturally deadlock. On resume, this path
is triggered when the running system tries to continue using its
devices. If it cannot then the resume will fail; to try to avoid this
we let it dip into the emergency pools.
[ linux-2.6.18-xen changesets e8b49cfbdac, fdb998e79aba ]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Return 0 instead of -EINVAL if the blkfront device is a cdrom,
i.e. had the VDISK_CDROM attribute. This allows udev's cdrom_id
to correctly detect the device as a cdrom device.
[ Add blkif_ioctl, and CDROMMULTISESSION ]
[ linux-2.6.18-xen changeset d2bd9af846b5 ]
Signed-off-by: Christian Limpach <Christian.Limpach@xensource.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Add support for the next generation of HP Smart Array SAS/SATA
controllers. Shipping date is late Fall 2008.
Bump the driver version to 3.6.20 to reflect the new hardware support from
patch 1 of this set.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alias brd to rd in the hope of helping legacy users. Suggested by Jan.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hello Rusty,
sometimes it is useful to share a disk (e.g. usr). To avoid file system
corruption, the disk should be mounted read-only in that case. This patch
adds a new feature flag, that allows the host to specify, if the disk should
be considered read-only.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fix a modprobe virtio_blk ; rmmod virtio_blk ; modprobe virtio_blk crash; this
was basically because we weren't doing "del_gendisk()" in the remove path.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (moved del_gendisk up)
In 2.6.25, ramdisk devices show up in /proc/partitions, which is a
behaviour change from the old rd.c. Add GENHD_FL_SUPPRESS_PARTITION_INFO,
which was present in rd.c.
All kernels prior to 2.6.25 weren't displaying ramdisks in
/proc/partitions. Since there are many userspace tools using information
from /proc/partitions some of them may now behave incorrectly (I didn't
tested any though). For example before 2.6.25 /proc/partitions was empty
if no block devices like hard disks and such were detected by kernel. Now
all 16 ramdisks are always visible there. Some software may rely on such
information (I mean, on empty /proc/partitions).
There was quite similar situation back in 2004, and ramdisks were excluded
back from displaying. Thats why I called this a regression (maybe a bit
unfortunate). See this patch for info:
http://kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.3-rc2/2.6.3-rc2-mm1/broken-out/nbd-proc-partitions-fix.patch
I also think that someone somewhere (long time ago) excluded ramdisks from
/proc/partitions for good reasons. It is possible that now such new
"feature" is harmless, but I think there are more chances that someone
will say "hey, /proc/partitions has changed, now my software doesn't work"
then "hey where did my new 2.6.25 feature go". nbd devices are also
excluded, maybe for very same (unknown to me) reasons.
Signed-off-by: Marcin Krol <hawk@pld-linux.org>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I don't use my IBM email address normally and people can find me in
CREDITS.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
According to the tests in do_initcalls(), the proper error code in case no
device is found is -ENODEV, not -ENXIO or -EIO.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
get_part() is fairly expensive, as it O(N) loops over partitions
to find the right one. In lots of normal IO paths we end up looking
up the partition twice, to make matters even worse. Change the
stat add code to accept a passed in partition instead.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (32 commits)
USB GADGET/PERIPHERAL: g_file_storage Bulk-Only Transport compliance, clear-feature ignore
USB GADGET/PERIPHERAL: g_file_storage Bulk-Only Transport compliance
usb_serial: some coding style fixes
USB: Remove redundant dependencies on USB_ATM.
USB: UHCI: disable remote wakeup when it's not needed
USB: OHCI: work around bogus compiler warning
USB: add Cypress c67x00 OTG controller HCD driver
USB: add Cypress c67x00 OTG controller core driver
USB: add Cypress c67x00 low level interface code
USB: airprime: unlock mutex instead of trying to lock it again
USB: storage: Update mailling list address
USB: storage: UNUSUAL_DEVS() for PanDigital Picture frame.
USB: Add the USB 2.0 extension descriptor.
USB: add more FTDI device ids
USB: fix cannot work usb storage when using ohci-sm501
usb: gadget zero timer init fix
usb: gadget zero style fixups (mostly whitespace)
usb serial gadget: CDC ACM fixes
usb: pxa27x_udc driver
USB: INTOVA Pixtreme camera mass storage device
...
I hoped to continue to ignore this problem or use libusual, but these
days it's simpler to work around than to deal with it. Let's attempt to
use bad residue devices and hope that upper level integrity checks catch
any problems (e.g. please use sha1sum on your backups).
Signed-off-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The wodim says:
"close track/session scsi sendcmd: cmd timeout after 5.000 (480) s"
This happened because we ignored the supplied timeout and used 5s.
It's not completely correct to apply a timeout meant for the complete
command to any single URB, but we don't have many URBs per command, so
this is simple and works.
Signed-off-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Rather than faking up some geometry, allow the backend to push the disk
geometry via virtio pci config option. Keep the old geo code around for
compatibility.
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (modified to single struct)
A recent proposed feature addition to the virtio block driver revealed
some flaws in the API: in particular, we assume that feature
negotiation is complete once a driver's probe function returns.
There is nothing in the API to require this, however, and even I
didn't notice when it was violated.
So instead, we require the driver to specify what features it supports
in a table, we can then move the feature negotiation into the virtio
core. The intersection of device and driver features are presented in
a new 'features' bitmap in the struct virtio_device.
Note that this highlights the difference between Linux unsigned-long
bitmaps where each unsigned long is in native endian, and a
straight-forward little-endian array of bytes.
Drivers can still remove feature bits in their probe routine if they
really have to.
API changes:
- dev->config->feature() no longer gets and acks a feature.
- drivers should advertise their features in the 'feature_table' field
- use virtio_has_feature() for extra sanity when checking feature bits
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
A recent proposed feature addition to the virtio block driver revealed
some flaws in the API, in particular how easy it is to break big
endian machines.
The virtio config space was originally chosen to be little-endian,
because we thought the config might be part of the PCI config space
for virtio_pci. It's actually a separate mmio region, so that
argument holds little water; as only x86 is currently using the virtio
mechanism, we can change this (but must do so now, before the
impending s390 merge).
API changes:
- __virtio_config_val() just becomes a striaght vdev->config_get() call.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Do not unregister the major at device remove, since there might be
another device instances around.
(qemu) pci_del 0 11
(qemu) ACPI: PCI interrupt for device 0000:00:0b.0 disabled
(qemu) pci_del 0 10
(qemu) ------------[ cut here ]------------
WARNING: at block/genhd.c:126 unregister_blkdev+0x74/0x9e()
ACPI: PCI interrupt for device 0000:00:0a.0 disabled
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Ron Minnich points out that a struct containing a char is not always
sizeof(char); simplest to remove the structure to avoid confusion.
Cc: "ron minnich" <rminnich@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Simply replace proc_create and further data assigned with proc_create_data.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Alexey Dobriyan <adobriyan@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Mike Miller <mike.miller@hp.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds partition management for Block RAM Device (BRD).
This patch is done to keep in sync BRD and loop device drivers.
This patch adds a parameter to the module, max_part, to specify
the maximum number of partitions per RAM device.
Example:
# modprobe brd max_part=63
# ls -l /dev/ram*
brw-rw---- 1 root disk 1, 0 2008-04-03 13:39 /dev/ram0
brw-rw---- 1 root disk 1, 64 2008-04-03 13:39 /dev/ram1
brw-rw---- 1 root disk 1, 640 2008-04-03 13:39 /dev/ram10
brw-rw---- 1 root disk 1, 704 2008-04-03 13:39 /dev/ram11
brw-rw---- 1 root disk 1, 768 2008-04-03 13:39 /dev/ram12
brw-rw---- 1 root disk 1, 832 2008-04-03 13:39 /dev/ram13
brw-rw---- 1 root disk 1, 896 2008-04-03 13:39 /dev/ram14
brw-rw---- 1 root disk 1, 960 2008-04-03 13:39 /dev/ram15
brw-rw---- 1 root disk 1, 128 2008-04-03 13:39 /dev/ram2
brw-rw---- 1 root disk 1, 192 2008-04-03 13:39 /dev/ram3
brw-rw---- 1 root disk 1, 256 2008-04-03 13:39 /dev/ram4
brw-rw---- 1 root disk 1, 320 2008-04-03 13:39 /dev/ram5
brw-rw---- 1 root disk 1, 384 2008-04-03 13:39 /dev/ram6
brw-rw---- 1 root disk 1, 448 2008-04-03 13:39 /dev/ram7
brw-rw---- 1 root disk 1, 512 2008-04-03 13:39 /dev/ram8
brw-rw---- 1 root disk 1, 576 2008-04-03 13:39 /dev/ram9
# fdisk /dev/ram0
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): o
Building a new DOS disklabel. Changes will remain in memory only,
until you decide to write them. After that, of course, the previous
content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-2, default 1): 1
Last cylinder or +size or +sizeM or +sizeK (1-2, default 2): 2
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
# ls -l /dev/ram0*
brw-rw---- 1 root disk 1, 0 2008-04-03 13:40 /dev/ram0
brw-rw---- 1 root disk 1, 1 2008-04-03 13:40 /dev/ram0p1
# mkfs /dev/ram0p1
mke2fs 1.40-WIP (14-Nov-2006)
Filesystem label=
OS type: Linux
Block size=1024 (log=0)
Fragment size=1024 (log=0)
4016 inodes, 16032 blocks
801 blocks (5.00%) reserved for the super user
First data block=1
Maximum filesystem blocks=16515072
2 block groups
8192 blocks per group, 8192 fragments per group
2008 inodes per group
Superblock backups stored on blocks:
8193
Writing inode tables: done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 26 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
# mount /dev/ram0p1 /mnt
df /mnt
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/ram0p1 15521 138 14582 1% /mnt
# ls -l /mnt
total 12
drwx------ 2 root root 12288 2008-04-03 13:41 lost+found
# umount /mnt
# rmmod brd
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* '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
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Ed L. Cashin <ecashin@coraid.com>
Cc: Jens Axboe <jens.axboe@oracle.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>
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>
Remove the no longer used aoedev_isbusy().
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
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>