Commit Graph

251 Commits

Author SHA1 Message Date
Konrad Rzeszutek Wilk 5ea4298669 xen/blk[front|back]: Enhance discard support with secure erasing support.
Part of the blkdev_issue_discard(xx) operation is that it can also
issue a secure discard operation that will permanantly remove the
sectors in question. We advertise that we can support that via the
'discard-secure' attribute and on the request, if the 'secure' bit
is set, we will attempt to pass in REQ_DISCARD | REQ_SECURE.

CC: Li Dongyang <lidongyang@novell.com>
[v1: Used 'flag' instead of 'secure:1' bit]
[v2: Use 'reserved' uint8_t instead of adding a new value]
[v3: Check for nseg when mapping instead of operation]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-18 13:28:01 -05:00
Konrad Rzeszutek Wilk 97e36834f5 xen/blk[front|back]: Squash blkif_request_rw and blkif_request_discard together
In a union type structure to deal with the overlapping
attributes in a easier manner.

Suggested-by: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-11-18 13:27:59 -05:00
Linus Torvalds 3d0a8d10cf Merge branch 'for-3.2/drivers' of git://git.kernel.dk/linux-block
* 'for-3.2/drivers' of git://git.kernel.dk/linux-block: (30 commits)
  virtio-blk: use ida to allocate disk index
  hpsa: add small delay when using PCI Power Management to reset for kump
  cciss: add small delay when using PCI Power Management to reset for kump
  xen/blkback: Fix two races in the handling of barrier requests.
  xen/blkback: Check for proper operation.
  xen/blkback: Fix the inhibition to map pages when discarding sector ranges.
  xen/blkback: Report VBD_WSECT (wr_sect) properly.
  xen/blkback: Support 'feature-barrier' aka old-style BARRIER requests.
  xen-blkfront: plug device number leak in xlblk_init() error path
  xen-blkfront: If no barrier or flush is supported, use invalid operation.
  xen-blkback: use kzalloc() in favor of kmalloc()+memset()
  xen-blkback: fixed indentation and comments
  xen-blkfront: fix a deadlock while handling discard response
  xen-blkfront: Handle discard requests.
  xen-blkback: Implement discard requests ('feature-discard')
  xen-blkfront: add BLKIF_OP_DISCARD and discard request struct
  drivers/block/loop.c: remove unnecessary bdev argument from loop_clr_fd()
  drivers/block/loop.c: emit uevent on auto release
  drivers/block/cpqarray.c: use pci_dev->revision
  loop: always allow userspace partitions and optionally support automatic scanning
  ...

Fic up trivial header file includsion conflict in drivers/block/loop.c
2011-11-04 17:22:14 -07:00
Laszlo Ersek 469738e675 xen-blkfront: plug device number leak in xlblk_init() error path
... though after a failed xenbus_register_frontend() all may be lost.

Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13 09:48:35 -04:00
Konrad Rzeszutek Wilk d11e615830 xen-blkfront: If no barrier or flush is supported, use invalid operation.
Guard against issuing BLKIF_OP_WRITE_BARRIER or BLKIF_OP_FLUSH_CACHE
by checking whether we successfully negotiated with the backend.
The negotiation with the backend also sets the q->flush_flags which
fortunately for us is also used when submitting an bio to us. If
we don't support barriers or flushes it would be set to zero so
we should never end up having to deal with REQ_FLUSH | REQ_FUA.

However, other third party implementations of __make_request that
might be stacked on top of us might not be so smart, so lets fix this up.

Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13 09:48:35 -04:00
Li Dongyang 69ef68cef9 xen-blkfront: fix a deadlock while handling discard response
When we get -EOPNOTSUPP response for a discard request, we will clear
the discard flag on the request queue so we won't attempt to send discard
requests to backend again, and this should be protected under rq->queue_lock.
However, when we setup the request queue, we pass blkif_io_lock to
blk_init_queue so rq->queue_lock is blkif_io_lock indeed, and this lock
is already taken when we are in blkif_interrpt, so remove the
spin_lock/spin_unlock when we clear the discard flag or we will end up
with deadlock here

Signed-off-by: Li Dongyang <lidongyang@novell.com>
[v1: Updated description a bit and removed comment from source]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13 09:48:32 -04:00
Li Dongyang ed30bf317c xen-blkfront: Handle discard requests.
If the backend advertises 'feature-discard', then interrogate
the backend for alignment and granularity. Setup the request
queue with the appropiate values and send the discard operation
as required.

Signed-off-by: Li Dongyang <lidongyang@novell.com>
[v1: Amended commit description]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-10-13 09:48:31 -04:00
Stefan Bader 89153b5cae xen-blkfront: Fix one off warning about name clash
Avoid telling users to use xvde and onwards when using xvde.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-14 14:19:51 -04:00
Stefan Bader 196cfe2ae8 xen-blkfront: Drop name and minor adjustments for emulated scsi devices
These were intended to avoid the namespace clash when representing
emulated IDE and SCSI devices. However that seems to confuse users
more than expected (a disk defined as sda becomes xvde).
So for now go back to the scheme which does no adjustments. This
will break when mixing IDE and SCSI names in the configuration of
guests but should be by now expected.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-14 14:19:33 -04:00
Konrad Rzeszutek Wilk edf6ef59ec xen-blkfront: Introduce BLKIF_OP_FLUSH_DISKCACHE support.
If the backend supports the 'feature-flush-cache' mode, use that
instead of the 'feature-barrier' support.

Currently there are three backends that support the 'feature-flush-cache'
mode: NetBSD, Solaris and Linux kernel. The 'flush' option is much
light-weight version than the 'barrier' support so lets try to use as
there are no filesystems in the kernel that use full barriers anymore.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12 08:56:03 -04:00
Marek Marczykowski 4352b47ab7 xen-blkfront: fix data size for xenbus_gather in blkfront_connect
barrier variable is int, not long. This overflow caused another variable
override: "err" (in PV code) and "binfo" (in xenlinux code -
drivers/xen/blkfront/blkfront.c). The later caused incorrect device
flags (RO/removable etc).

Signed-off-by: Marek Marczykowski <marmarek@mimuw.edu.pl>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
[v1: Changed title]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-12 08:55:51 -04:00
Linus Torvalds 76ca078328 Merge branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm
* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
  xen: suspend: remove xen_hvm_suspend
  xen: suspend: pull pre/post suspend hooks out into suspend_info
  xen: suspend: move arch specific pre/post suspend hooks into generic hooks
  xen: suspend: refactor non-arch specific pre/post suspend hooks
  xen: suspend: add "arch" to pre/post suspend hooks
  xen: suspend: pass extra hypercall argument via suspend_info struct
  xen: suspend: refactor cancellation flag into a structure
  xen: suspend: use HYPERVISOR_suspend for PVHVM case instead of open coding
  xen: switch to new schedop hypercall by default.
  xen: use new schedop interface for suspend
  xen: do not respond to unknown xenstore control requests
  xen: fix compile issue if XEN is enabled but XEN_PVHVM is disabled
  xen: PV on HVM: support PV spinlocks and IPIs
  xen: make the ballon driver work for hvm domains
  xen-blkfront: handle Xen major numbers other than XENVBD
  xen: do not use xen_info on HVM, set pv_info name to "Xen HVM"
  xen: no need to delay xen_setup_shutdown_event for hvm guests anymore
2011-03-15 10:59:09 -07:00
Owen Smith 51de69523f xen: Union the blkif_request request specific fields
Prepare for extending the block device ring to allow request
specific fields, by moving the request specific fields for
reads, writes and barrier requests to a union member.

Acked-by: Jens Axboe <jaxboe@fusionio.com>
Signed-off-by: Owen Smith <owen.smith@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-08 15:07:00 -05:00
Stefano Stabellini c80a420995 xen-blkfront: handle Xen major numbers other than XENVBD
This patch makes sure blkfront handles correctly virtual device numbers
corresponding to Xen emulated IDE and SCSI disks: in those cases
blkfront translates the major number to XENVBD and the minor number to a
low xvd minor.

Note: this behaviour is different from what old xenlinux PV guests used
to do: they used to steal an IDE or SCSI major number and use it
instead.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
2011-02-25 16:43:05 +00:00
Linus Torvalds 23d69b09b7 Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (33 commits)
  usb: don't use flush_scheduled_work()
  speedtch: don't abuse struct delayed_work
  media/video: don't use flush_scheduled_work()
  media/video: explicitly flush request_module work
  ioc4: use static work_struct for ioc4_load_modules()
  init: don't call flush_scheduled_work() from do_initcalls()
  s390: don't use flush_scheduled_work()
  rtc: don't use flush_scheduled_work()
  mmc: update workqueue usages
  mfd: update workqueue usages
  dvb: don't use flush_scheduled_work()
  leds-wm8350: don't use flush_scheduled_work()
  mISDN: don't use flush_scheduled_work()
  macintosh/ams: don't use flush_scheduled_work()
  vmwgfx: don't use flush_scheduled_work()
  tpm: don't use flush_scheduled_work()
  sonypi: don't use flush_scheduled_work()
  hvsi: don't use flush_scheduled_work()
  xen: don't use flush_scheduled_work()
  gdrom: don't use flush_scheduled_work()
  ...

Fixed up trivial conflict in drivers/media/video/bt8xx/bttv-input.c
as per Tejun.
2011-01-07 16:58:04 -08:00
Tejun Heo 30d65030fd xen: don't use flush_scheduled_work()
flush_scheduled_work() is deprecated and scheduled to be removed.
Directly flush info->work instead.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-12-24 15:59:06 +01:00
Jeremy Fitzhardinge 667c78afae xen: Provide a variant of __RING_SIZE() that is an integer constant expression
Without this, gcc 4.5 won't compile xen-netfront and xen-blkfront, where
this is being used to specify array sizes.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: David Miller <davem@davemloft.net>
Cc: Stable Kernel <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-15 12:34:28 -08:00
Christoph Hellwig 02e031cbc8 block: remove REQ_HARDBARRIER
REQ_HARDBARRIER is dead now, so remove the leftovers.  What's left
at this point is:

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

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-11-10 14:54:09 +01:00
Jeremy Fitzhardinge dcb8baecea xen/blkfront: cope with backend that fail empty BLKIF_OP_WRITE_BARRIER requests
Some(?) Xen block backends fail BLKIF_OP_WRITE_BARRIER requests, which
Linux uses as a cache flush operation.  In that case, disable use
of FLUSH.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Daniel Stodden <daniel.stodden@citrix.com>
2010-11-02 13:46:46 -04:00
Jeremy Fitzhardinge be2f8373c1 xen/blkfront: Implement FUA with BLKIF_OP_WRITE_BARRIER
The BLKIF_OP_WRITE_BARRIER is a full ordered barrier, so we can use it
to implement FUA as well as a plain FLUSH.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2010-11-02 11:27:59 -04:00
Jeremy Fitzhardinge a945b9801a xen/blkfront: change blk_shadow.request to proper pointer
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-11-02 11:27:58 -04:00
Jeremy Fitzhardinge c64e38ea17 xen/blkfront: map REQ_FLUSH into a full barrier
Implement a flush as a full barrier, since we have nothing weaker.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Christoph Hellwig <hch@lst.de>
2010-11-02 10:43:51 -04:00
Linus Torvalds 18cb657ca1 Merge branch 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
and branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm

* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
  xen: register xen pci notifier
  xen: initialize cpu masks for pv guests in xen_smp_init
  xen: add a missing #include to arch/x86/pci/xen.c
  xen: mask the MTRR feature from the cpuid
  xen: make hvc_xen console work for dom0.
  xen: add the direct mapping area for ISA bus access
  xen: Initialize xenbus for dom0.
  xen: use vcpu_ops to setup cpu masks
  xen: map a dummy page for local apic and ioapic in xen_set_fixmap
  xen: remap MSIs into pirqs when running as initial domain
  xen: remap GSIs as pirqs when running as initial domain
  xen: introduce XEN_DOM0 as a silent option
  xen: map MSIs into pirqs
  xen: support GSI -> pirq remapping in PV on HVM guests
  xen: add xen hvm acpi_register_gsi variant
  acpi: use indirect call to register gsi in different modes
  xen: implement xen_hvm_register_pirq
  xen: get the maximum number of pirqs from xen
  xen: support pirq != irq

* 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (27 commits)
  X86/PCI: Remove the dependency on isapnp_disable.
  xen: Update Makefile with CONFIG_BLOCK dependency for biomerge.c
  MAINTAINERS: Add myself to the Xen Hypervisor Interface and remove Chris Wright.
  x86: xen: Sanitse irq handling (part two)
  swiotlb-xen: On x86-32 builts, select SWIOTLB instead of depending on it.
  MAINTAINERS: Add myself for Xen PCI and Xen SWIOTLB maintainer.
  xen/pci: Request ACS when Xen-SWIOTLB is activated.
  xen-pcifront: Xen PCI frontend driver.
  xenbus: prevent warnings on unhandled enumeration values
  xenbus: Xen paravirtualised PCI hotplug support.
  xen/x86/PCI: Add support for the Xen PCI subsystem
  x86: Introduce x86_msi_ops
  msi: Introduce default_[teardown|setup]_msi_irqs with fallback.
  x86/PCI: Export pci_walk_bus function.
  x86/PCI: make sure _PAGE_IOMAP it set on pci mappings
  x86/PCI: Clean up pci_cache_line_size
  xen: fix shared irq device passthrough
  xen: Provide a variant of xen_poll_irq with timeout.
  xen: Find an unbound irq number in reverse order (high to low).
  xen: statically initialize cpu_evtchn_mask_p
  ...

Fix up trivial conflicts in drivers/pci/Makefile
2010-10-28 17:11:17 -07:00
Linus Torvalds a2887097f2 Merge branch 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block: (46 commits)
  xen-blkfront: disable barrier/flush write support
  Added blk-lib.c and blk-barrier.c was renamed to blk-flush.c
  block: remove BLKDEV_IFL_WAIT
  aic7xxx_old: removed unused 'req' variable
  block: remove the BH_Eopnotsupp flag
  block: remove the BLKDEV_IFL_BARRIER flag
  block: remove the WRITE_BARRIER flag
  swap: do not send discards as barriers
  fat: do not send discards as barriers
  ext4: do not send discards as barriers
  jbd2: replace barriers with explicit flush / FUA usage
  jbd2: Modify ASYNC_COMMIT code to not rely on queue draining on barrier
  jbd: replace barriers with explicit flush / FUA usage
  nilfs2: replace barriers with explicit flush / FUA usage
  reiserfs: replace barriers with explicit flush / FUA usage
  gfs2: replace barriers with explicit flush / FUA usage
  btrfs: replace barriers with explicit flush / FUA usage
  xfs: replace barriers with explicit flush / FUA usage
  block: pass gfp_mask and flags to sb_issue_discard
  dm: convey that all flushes are processed as empty
  ...
2010-10-22 17:07:18 -07:00
Jens Axboe 005a1d15f5 xen-blkfront: disable barrier/flush write support
The driver doesn't handle empty flushes. Disable barrier/flush
write support until this is fixed up.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-22 10:58:33 +02:00
Jens Axboe fa251f8990 Merge branch 'v2.6.36-rc8' into for-2.6.37/barrier
Conflicts:
	block/blk-core.c
	drivers/block/loop.c
	mm/swapfile.c

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-10-19 09:13:04 +02:00
Noboru Iwamatsu b78c951256 xenbus: prevent warnings on unhandled enumeration values
XenbusStateReconfiguring/XenbusStateReconfigured were introduced by
c/s 437, but aren't handled in many switch statements.

.. also pulled from the linux-2.6-sparse-tree tree.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-10-18 10:49:36 -04:00
Arnd Bergmann 2a48fc0ab2 block: autoconvert trivial BKL users to private mutex
The block device drivers have all gained new lock_kernel
calls from a recent pushdown, and some of the drivers
were already using the BKL before.

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

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

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

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-05 15:01:10 +02:00
Tejun Heo 4913efe456 block: deprecate barrier and replace blk_queue_ordered() with blk_queue_flush()
Barrier is deemed too heavy and will soon be replaced by FLUSH/FUA
requests.  Deprecate barrier.  All REQ_HARDBARRIERs are failed with
-EOPNOTSUPP and blk_queue_ordered() is replaced with simpler
blk_queue_flush().

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

All blk_queue_ordered() users are converted.

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

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Boaz Harrosh <bharrosh@panasas.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-10 12:35:36 +02:00
Tejun Heo 6958f14545 block: kill QUEUE_ORDERED_BY_TAG
Nobody is making meaningful use of ORDERED_BY_TAG now and queue
draining for barrier requests will be removed soon which will render
the advantage of tag ordering moot.  Kill ORDERED_BY_TAG.  The
following users are affected.

* brd: converted to ORDERED_DRAIN.
* virtio_blk: ORDERED_TAG path was already marked deprecated.  Removed.
* xen-blkfront: ORDERED_TAG case dropped.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-09-10 12:35:36 +02:00
Ian Campbell 1dc7ce99b0 xen: pvhvm: rename xen_emul_unplug=ignore to =unnnecessary
It is not immediately clear what this option causes to become
ignored. The actual meaning is that it is not necessary to unplug the
emulated devices to safely use the PV ones, even if the platform does
not support the unplug protocol. (pressumably the user will only add
this option if they have ensured that their domain configuration is
safe).

I think xen_emul_unplug=unnecessary better captures this.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
2010-08-23 11:59:29 +01:00
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
Jens Axboe a4cc14ec9f xen-blkfront: fix missing out label
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-08 21:50:05 -04:00
Jeremy Fitzhardinge 7901d14144 xen/blkfront: Use QUEUE_ORDERED_DRAIN for old backends
If there's no feature-barrier key in xenstore, then it means its a fairly
old backend which does uncached in-order writes, which means ORDERED_DRAIN
is appropriate.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:52:53 +02:00
Jeremy Fitzhardinge 4dab46ff26 xen/blkfront: use tagged queuing for barriers
When barriers are supported, then use QUEUE_ORDERED_TAG to tell the block
subsystem that it doesn't need to do anything else with the barriers.
Previously we used ORDERED_DRAIN which caused the block subsystem to
drain all pending IO before submitting the barrier, which would be
very expensive.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:52:53 +02:00
Daniel Stodden d54142c71f blkfront: Klog the unclean release path
Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:51:21 +02:00
Daniel Stodden 7b32d1044a blkfront: Remove obsolete info->users
This is just bd_openers, protected by the bd_mutex.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:49:20 +02:00
Daniel Stodden acfca3c622 blkfront: Remove obsolete info->users
This is just bd_openers, protected by the bd_mutex.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:47:26 +02:00
Daniel Stodden fa1bd3591a blkfront: Lock blockfront_info during xbdev removal
Same approach as blkfront_closing:
 * Grab the bdev safely, holding the info mutex.
 * Zap xbdev safely, holding the info mutex.
 * Try bdev removal safely, holding bd_mutex.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:45:27 +02:00
Daniel Stodden 7fd152f4b6 blkfront: Fix blkfront backend switch race (bdev release)
We cannot read backend state within bdev operations, because it risks
grabbing the state change before xenbus gets to do it.

Fixed by tracking deferral with a frontend switch to Closing. State
exposure isn't strictly necessary, but the backends won't mind.

For a 'clean' deferral this seems actually a more decent protocol than
raising errors.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:45:12 +02:00
Daniel Stodden 139617437a blkfront: Fix blkfront backend switch race (bdev open)
We need not mind if users grab a late handle on a closing disk. We
probably even should not. But we have to make sure it's not a dead
one already

Let the bdev deal with a gendisk deleted under its feet. Takes the
info mutex to decide a race against backend closing.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:38:43 +02:00
Daniel Stodden b70f5fa043 blkfront: Lock blkfront_info when closing
The bdev .open/.release fops race against backend switches to Closing,
handled by the XenBus thread.

The original code attempted to serialize block device holders and
xenbus only via bd_mutex. This is insufficient, the info->bd pointer
may already be stale (or null) while xenbus tries to bump up the
refcount.

Protect blkfront_info with a dedicated mutex.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:38:43 +02:00
Daniel Stodden a66b5aebb7 blkfront: Clean up vbd release
* Current blkfront_closing is rather a xlvbd_release_gendisk.
   Renamed in preparation of later patches (need the name again).

 * Removed the misleading comment -- this only applied to the backend
   switch handler, and the queue is already flushed btw.

 * Break out the xenbus call, callers know better when to switch
   frontend state.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:38:43 +02:00
Daniel Stodden 9897cb5323 blkfront: Fix gendisk leak
Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:31:37 +02:00
Daniel Stodden 89de1669ac blkfront: Fix backtrace in del_gendisk
The call to del_gendisk follows an non-refcounted gd->queue
pointer. We release the last ref in blk_cleanup_queue. Fixed by
reordering releases accordingly.

Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:31:35 +02:00
K. Y. Srinivasan 2def141e71 xen/blkfront: revalidate after setting capacity
Signed-off-by: K. Y. Srinivasan <ksrinivasan@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:31:31 +02:00
Jeremy Fitzhardinge b4dddb498c xen/blkfront: avoid compiler warning from missing cases
Fix:
drivers/block/xen-blkfront.c: In function ‘blkfront_connect’:
drivers/block/xen-blkfront.c:933: warning: enumeration value ‘BLKIF_STATE_DISCONNECTED’ not handled in switch

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:31:29 +02:00
K. Y. Srinivasan 1fa73be6be xen/front: Propagate changed size of VBDs
Support dynamic resizing of virtual block devices. This patch supports
both file backed block devices as well as physical devices that can be
dynamically resized on the host side.

Signed-off-by: K. Y. Srinivasan <ksrinivasan@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:31:27 +02:00
Jan Beulich 5d7ed20e82 blkfront: don't access freed struct xenbus_device
Unfortunately commit "blkfront: fixes for 'xm block-detach ... --force'"
still wasn't quite right - there was a reference to freed memory left
from blkfront_closing().

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:31:12 +02:00
Jan Beulich 0e34582699 blkfront: fixes for 'xm block-detach ... --force'
Prevent prematurely freeing 'struct blkfront_info' instances (when the
xenbus data structures are gone, but the Linux ones are still needed).

Prevent adding a disk with the same (major, minor) [and hence the same
name and sysfs entries, which leads to oopses] when the previous
instance wasn't fully de-allocated yet.

This still doesn't address all issues resulting from forced detach:
I/O submitted after the detach still blocks forever, likely preventing
subsequent un-mounting from completing. It's not clear to me (not
knowing much about the block layer) how this can be avoided.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:28:55 +02:00
Ian Campbell 203fd61f42 xen: use less generic names in blkfront driver.
All Xen frontend drivers have a couple of identically named functions which
makes figuring out which device went wrong from a stacktrace harder than it
needs to be. Rename them to something specificto the device type.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-08-07 18:26:39 +02:00
Arnd Bergmann 6e9624b8ca block: push down BKL into .open and .release
The open and release block_device_operations are currently
called with the BKL held. In order to change that, we must
first make sure that all drivers that currently rely
on this have no regressions.

This blindly pushes the BKL into all .open and .release
operations for all block drivers to prepare for the
next step. The drivers can subsequently replace the BKL
with their own locks or remove it completely when it can
be shown that it is not needed.

The functions blkdev_get and blkdev_put are the only
remaining users of the big kernel lock in the block
layer, besides a few uses in the ioctl code, none
of which need to serialize with blkdev_{get,put}.

Most of these two functions is also under the protection
of bdev->bd_mutex, including the actual calls to
->open and ->release, and the common code does not
access any global data structures that need the BKL.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:25:34 +02:00
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
FUJITA Tomonori 00fff26539 block: remove q->prepare_flush_fn completely
This removes q->prepare_flush_fn completely (changes the
blk_queue_ordered API).

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:24:15 +02:00
Christoph Hellwig 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
Stefano Stabellini b98a409b80 blkfront: do not create a PV cdrom device if xen_hvm_guest
It is not possible to unplug emulated cdrom devices, and PV cdroms don't
handle media insert, eject and stream, so we are better off disabling PV
cdroms when running as a Xen HVM guest.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2010-07-29 11:11:08 -07:00
Stefano Stabellini c1c5413ad5 x86: Unplug emulated disks and nics.
Add a xen_emul_unplug command line option to the kernel to unplug
xen emulated disks and nics.

Set the default value of xen_emul_unplug depending on whether or
not the Xen PV frontends and the Xen platform PCI driver have
been compiled for this kernel (modules or built-in are both OK).

The user can specify xen_emul_unplug=ignore to enable PV drivers on HVM
even if the host platform doesn't support unplug.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-26 23:13:25 -07:00
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
Martin K. Petersen 8a78362c4e block: Consolidate phys_segment and hw_segment limits
Except for SCSI no device drivers distinguish between physical and
hardware segment limits.  Consolidate the two into a single segment
limit.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-02-26 13:58:08 +01:00
Martin K. Petersen 086fa5ff08 block: Rename blk_queue_max_sectors to blk_queue_max_hw_sectors
The block layer calling convention is blk_queue_<limit name>.
blk_queue_max_sectors predates this practice, leading to some confusion.
Rename the function to appropriately reflect that its intended use is to
set max_hw_sectors.

Also introduce a temporary wrapper for backwards compability.  This can
be removed after the merge window is closed.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-02-26 13:58:08 +01:00
Márton Németh ec9c42ec79 block: make xenbus device id constant
The ids field of the struct xenbus_device_id is constant in <linux/xen/xenbus.h>
so it is worth to make blkfront_ids also constant.

The semantic match that finds this kind of pattern is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r@
disable decl_init,const_decl_init;
identifier I1, I2, x;
@@
	struct I1 {
	  ...
	  const struct I2 *x;
	  ...
	};
@s@
identifier r.I1, y;
identifier r.x, E;
@@
	struct I1 y = {
	  .x = E,
	};
@c@
identifier r.I2;
identifier s.E;
@@
	const struct I2 E[] = ... ;
@depends on !c@
identifier r.I2;
identifier s.E;
@@
+	const
	struct I2 E[] = ...;
// </smpl>

Signed-off-by: Márton Németh <nm127@freemail.hu>
Cc: Julia Lawall <julia@diku.dk>
Cc: cocci@diku.dk
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-01-11 14:31:27 +01:00
Jeremy Fitzhardinge 1ccbf5344c xen: move Xen-testing predicates to common header
Move xen_domain and related tests out of asm-x86 to xen/xen.h so they
can be included whenever they are necessary.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-04 08:47:24 -08:00
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
Greg Kroah-Hartman a1b4b12b37 xen block: remove driver_data direct access of struct device
In the near future, the driver core is going to not allow direct access
to the driver_data pointer in struct device.  Instead, the functions
dev_get_drvdata() and dev_set_drvdata() should be used.  These functions
have been around since the beginning, so are backwards compatible with
all older kernel versions.


Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.osdl.org
Acked-by: Chris Wright <chrisw@sous-sol.org>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-06-15 21:30:27 -07:00
Martin K. Petersen e1defc4ff0 block: Do away with the notion of hardsect_size
Until now we have had a 1:1 mapping between storage device physical
block size and the logical block sized used when addressing the device.
With SATA 4KB drives coming out that will no longer be the case.  The
sector size will be 4KB but the logical block size will remain
512-bytes.  Hence we need to distinguish between the physical block size
and the logical ditto.

This patch renames hardsect_size to logical_block_size.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 23:22:54 +02:00
Jens Axboe 9bd7de51ee Merge branch 'master' into for-2.6.31
Conflicts:
	drivers/ide/ide-io.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 20:28:35 +02:00
Roel Kluin b9ed7252d2 xen-blkfront: beyond ARRAY_SIZE of info->shadow
Do not go beyond ARRAY_SIZE of info->shadow
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-22 09:59:51 +02:00
Ian Campbell 31a14400e8 xen/blkfront: fix warning when deleting gendisk on unplug/shutdown
Currently blkfront gives a warning when hot unplugging due to calling
del_gendisk() with interrupts disabled (due to blkif_io_lock).

WARNING: at kernel/softirq.c:124 local_bh_enable+0x36/0x84()
Modules linked in: xenfs xen_netfront ext3 jbd mbcache xen_blkfront
Pid: 13, comm: xenwatch Not tainted 2.6.29-xs5.5.0.13 #3
Call Trace:
 [<c012611c>] warn_slowpath+0x80/0xb6
 [<c0104cf1>] xen_sched_clock+0x16/0x63
 [<c0104710>] xen_force_evtchn_callback+0xc/0x10
 [<c0104e32>] check_events+0x8/0xe
 [<c0104d9b>] xen_restore_fl_direct_end+0x0/0x1
 [<c0103749>] xen_mc_flush+0x10a/0x13f
 [<c0105bd2>] __switch_to+0x114/0x14e
 [<c011d92b>] dequeue_task+0x62/0x70
 [<c0123b6f>] finish_task_switch+0x2b/0x84
 [<c0299877>] schedule+0x66d/0x6e7
 [<c0104710>] xen_force_evtchn_callback+0xc/0x10
 [<c0104710>] xen_force_evtchn_callback+0xc/0x10
 [<c012a642>] local_bh_enable+0x36/0x84
 [<c022f9a7>] sk_filter+0x57/0x5c
 [<c0233dae>] netlink_broadcast+0x1d5/0x315
 [<c01c6371>] kobject_uevent_env+0x28d/0x331
 [<c01e7ead>] device_del+0x10f/0x120
 [<c01e7ec6>] device_unregister+0x8/0x10
 [<c015f86d>] bdi_unregister+0x2d/0x39
 [<c01bf6f4>] unlink_gendisk+0x23/0x3e
 [<c01ac946>] del_gendisk+0x7b/0xe7
 [<d0828c19>] blkfront_closing+0x28/0x6e [xen_blkfront]
 [<d082900c>] backend_changed+0x3ad/0x41d [xen_blkfront]

We can fix this by calling del_gendisk() later in blkfront_closing, after
releasing blkif_io_lock. Since the queue is stopped during the interrupts
disabled phase I don't think there is any danger of an event occuring between
releasing the blkif_io_lock and deleting the disk.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-19 08:27:42 +02:00
Ian Campbell 28afea5b2f xen/blkfront: allow xenbus state transition to Closing->Closed when not Connected
This situation can occur when attempting to attach a block device whose
backend is an empty physical CD-ROM driver. The backend in this case
will go directly from the Initialising state to Closing->Closed.
Previously this would result in a NULL pointer deref on info->gd
(xenbus_dev_fatal does not return as a1a15ac5 seems to expect)

Cc: stable@kernel.org
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-19 08:25:48 +02:00
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 296b2f6ae6 block: convert to dequeueing model (easy ones)
plat-omap/mailbox, floppy, viocd, mspro_block, i2o_block and
mmc/card/queue are already pretty close to dequeueing model and can be
converted with simple changes.  Convert them.

While at it,

* xen-blkfront: !fs check moved downwards to share dequeue call with
  normal path.

* mspro_block: __blk_end_request(..., blk_rq_cur_byte()) converted to
  __blk_end_request_cur()

* mmc/card/queue: loop of __blk_end_request() converted to
  __blk_end_request_all()

[ Impact: dequeue in-flight request ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:52:17 +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 f06d9a2b52 block: replace end_request() with [__]blk_end_request_cur()
end_request() has been kept around for backward compatibility;
however, it's about time for it to go away.

* There aren't too many users left.

* Its use of @updtodate is pretty confusing.

* In some cases, newer code ends up using mixture of end_request() and
  [__]blk_end_request[_all](), which is way too confusing.

So, add [__]blk_end_request_cur() and replace end_request() with it.
Most conversions are straightforward.  Noteworthy ones are...

* paride/pcd: next_request() updated to take 0/-errno instead of 1/0.

* paride/pf: pf_end_request() and next_request() updated to take
  0/-errno instead of 1/0.

* xd: xd_readwrite() updated to return 0/-errno instead of 1/0.

* mtd/mtd_blkdevs: blktrans_discard_request() updated to return
  0/-errno instead of 1/0.  Unnecessary local variable res
  initialization removed from mtd_blktrans_thread().

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Joerg Dorchain <joerg@dorchain.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Laurent Vivier <Laurent@lvivier.info>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: unsik Kim <donari75@gmail.com>
2009-04-28 07:37:36 +02:00
Tejun Heo 40cbbb781d block: implement and use [__]blk_end_request_all()
There are many [__]blk_end_request() call sites which call it with
full request length and expect full completion.  Many of them ensure
that the request actually completes by doing BUG_ON() the return
value, which is awkward and error-prone.

This patch adds [__]blk_end_request_all() which takes @rq and @error
and fully completes the request.  BUG_ON() is added to to ensure that
this actually happens.

Most conversions are simple but there are a few noteworthy ones.

* cdrom/viocd: viocd_end_request() replaced with direct calls to
  __blk_end_request_all().

* s390/block/dasd: dasd_end_request() replaced with direct calls to
  __blk_end_request_all().

* s390/char/tape_block: tapeblock_end_request() replaced with direct
  calls to blk_end_request_all().

[ Impact: cleanup ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-04-28 07:37:35 +02:00
Kris Shannon a1a15ac5f9 Fix kernel NULL pointer dereference in xen-blkfront
When booting Xen Dom0 on a pre-release 3.2.1 hypervisor the system Oopses on a
"Unable to handle kernel NULL pointer dereference" in xenwatch.

From the backtrace it looks like backend_changed is calling bdget_disk
with a NULL pointer.  Checking for NULL and returning ENODEV instead
allows the kernel to boot.
2009-03-05 12:04:57 +01:00
Jens Axboe 9e973e64ac xen/blkfront: use blk_rq_map_sg to generate ring entries
On occasion, the request will apparently have more segments than we
fit into the ring. Jens says:

> The second problem is that the block layer then appears to create one
> too many segments, but from the dump it has rq->nr_phys_segments ==
> BLKIF_MAX_SEGMENTS_PER_REQUEST. I suspect the latter is due to
> xen-blkfront not handling the merging on its own. It should check that
> the new page doesn't form part of the previous page. The
> rq_for_each_segment() iterates all single bits in the request, not dma
> segments. The "easiest" way to do this is to call blk_rq_map_sg() and
> then iterate the mapped sg list. That will give you what you are
> looking for.

> Here's a test patch, compiles but otherwise untested. I spent more
> time figuring out how to enable XEN than to code it up, so YMMV!
> Probably the sg list wants to be put inside the ring and only
> initialized on allocation, then you can get rid of the sg on stack and
> sg_init_table() loop call in the function. I'll leave that, and the
> testing, to you.

[Moved sg array into info structure, and initialize once. -J]

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-02-26 10:45:48 +01:00
Fernando Luis Vázquez Cao 66d352e1e4 xen-blkfront: set queue paravirt flag
Xen's blkfront sets noop as the default I/O scheduler at initialization
time to avoid elevator overheads such as idling, but with the advent of
basic disk profiling capabilities this is not necessary anymore. We
should just tell the block layer that we are a paravirt front-end driver
and the elevator will automatically make the necessary adjustments.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-12-29 08:28:41 +01:00
Zhaolei 68aee07f9b Release old elevator on change elevator
We should release old elevator when change to use a new one.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-11-18 15:08:56 +01:00
Al Viro a63c848b04 [PATCH] switch xen
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21 07:48:13 -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
Ingo Molnar 365d46dc9b Merge branch 'linus' into x86/xen
Conflicts:
	arch/x86/kernel/cpu/common.c
	arch/x86/kernel/process_64.c
	arch/x86/xen/enlighten.c
2008-10-12 12:37:32 +02:00
Chris Lalancette 9246b5f06d block: Expand Xen blkfront for > 16 xvd
Until recently, the maximum number of xvd block devices you could attach
to a Xen domU was 16. This limitation turned out to be problematic for
some users, so it was expanded to handle a much larger number of disks.
However, this requires a couple of changes in the way that blkfront
scans for disks. This functionality is already present in the Xen
linux-2.6.18-xen.hg tree; the attached patch adds this functionality to
the mainline xen-blkfront implementation. I successfully tested it on a
2.6.25 tree, and build tested it on 2.6.27-rc3.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-10-09 08:56:18 +02:00
Jeremy Fitzhardinge 6e833587e1 xen: clean up domain mode predicates
There are four operating modes Xen code may find itself running in:
 - native
 - hvm domain
 - pv dom0
 - pv domU

Clean up predicates for testing for these states to make them more consistent.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-20 12:40:07 +02:00
Adrian Bunk 62aa0054da xen-blkfront.c: make blkif_ioctl() static
This patch makes the needlessly global blkif_ioctl() static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-08-06 12:30:04 +02:00
Ian Campbell a144ff09bc xen: Avoid allocations causing swap activity on the resume path
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>
2008-07-03 13:21:13 +02:00
Jan Beulich 5a60d0cd4f xen/blkfront: add __exit to module_exit() handlers
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:13 +02:00
Wim Colgate 04c0635058 xen/blkfront: Make sure that the device is fully ready before allowing release.
[ linux-2.6.18-xen changeset c1c57fea77e9 ]

Signed-off-by: Wim Colgate <wim@xensource.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:13 +02:00
Christian Limpach 440a01a7f4 xen/blkfront: Add the CDROM_GET_CAPABILITY ioctl to blkfront.
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>
2008-07-03 13:21:13 +02:00
Ian Campbell 1c91fe1a0d xen/blkfront: Make sure we don't use bounce buffers, we don't need them.
[ linux-2.6.18-xen changeset 667228bf8fc5 ]

Signed-off-by: Ian Campbell <ian.campbell@xensource.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-07-03 13:21:12 +02:00
Harvey Harrison afe42d7dea xen: make blkif_getgeo static
Introduced between 2.6.25-rc2 and -rc3
drivers/block/xen-blkfront.c:139:5: warning: symbol 'blkif_getgeo' was not declared. Should it be static?

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
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>
2008-04-29 08:06:06 -07:00
Mark McLoughlin 4f93f09b72 xen: Add compatibility aliases for frontend drivers
Before getting merged, xen-blkfront was xenblk and
xen-netfront was xennet.

Temporarily adding compatibility module aliases
eases upgrades from older versions by e.g. allowing
mkinitrd to find the new version of the module.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:33 +02:00
Mark McLoughlin d2f0c52bec xen: Module autoprobing support for frontend drivers
Add module aliases to support autoprobing modules
for xen frontend devices.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:33 +02:00
Christian Limpach 1d78d70556 xen blkfront: Delay wait for block devices until after the disk is added
When the xen block frontend driver is built as a module the module load
is only synchronous up to the point where the frontend and the backend
become connected rather than when the disk is added.

This means that there can be a race on boot between loading the module and
loading the dm-* modules and doing the scan for LVM physical volumes (all
in the initrd). In the failure case the disk is not present until after the
scan for physical volumes is complete.

Taken from:

  http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/11483a00c017

Signed-off-by: Christian Limpach <Christian.Limpach@xensource.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:33 +02:00
Jeremy Fitzhardinge 53f0e8afcb xen/blkfront: use bdget_disk
info->dev is never initialized to anything, so bdget(info->dev) is
meaningless.  Get rid of info->dev, and use bdget_disk on the gendisk.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:33 +02:00
Markus Armbruster 3e334239d8 xen: Make xen-blkfront write its protocol ABI to xenstore
Frontends are expected to write their protocol ABI to xenstore.  Since
the protocol ABI defaults to the backend's native ABI, things work
fine without that as long as the frontend's native ABI is identical to
the backend's native ABI.  This is not the case for xen-blkfront
running 32-on-64, because its ABI differs between 32 and 64 bit, and
thus needs this fix.

Based on http://xenbits.xensource.com/xen-unstable.hg?rev/c545932a18f3
and http://xenbits.xensource.com/xen-unstable.hg?rev/ffe52263b430 by
Gerd Hoffmann <kraxel@suse.de>

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:32 +02:00
Ian Campbell 597592d951 xen: Implement getgeo for Xen virtual block device.
The below implements the getgeo hook for Xen block devices. Extracted
from the xen-unstable tree where it has been used for ages.

It is useful to have because it allows things like grub2 (used by the
Debian installer images) to work in a guest domain without having to
sprinkle Xen specific hacks around the place.

Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-21 16:19:13 -08:00
Kiyoshi Ueda f530f03637 blk_end_request: changing xen-blkfront (take 4)
This patch converts xen-blkfront to use blk_end_request interfaces.
Related 'uptodate' arguments are converted to 'error'.

Cc: Jeremy Fitzhardinge <jeremy@xensource.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 10:36:46 +01:00
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
Jeremy Fitzhardinge 9f27ee5950 xen: add virtual block device driver.
The block device frontend driver allows the kernel to access block
devices exported exported by a virtual machine containing a physical
block device driver.

Signed-off-by: Ian Pratt <ian.pratt@xensource.com>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Greg KH <greg@kroah.com>
Cc: Jens Axboe <axboe@kernel.dk>
2007-07-18 08:47:45 -07:00