Commit Graph

93 Commits

Author SHA1 Message Date
Justin T. Gibbs
0d17232400 Correct failure to attach the PV block front device on Citrix
XenServer configurations that advertise the multi-page ring extension,
but only allow a single page of ring space.

sys/dev/xen/blkfront/blkfront.c:
	If only one page of ring space is being used, do not publish
	in the XenStore the number of pages in use (1), via either
	of the supported multi-page ring extension schemes.

	Single page operation is the same with or without the
	ring-page extension being negotiated.   Relying on the
	legacy behavior avoids an incompatible difference in how
	the two ring-page extension schemes that are out in the
	wild, deal with the base case of a single page.  The
	Amazon/Red Hat drivers use the same XenStore variable as
	if the extension was not negotiated.  The Citrix drivers
	assume the new ring reference XenStore variables will be
	available

Reported by:	Oliver Schonefeld <schonefeld@ids-mannheim.de>
MFC after:	3 days
2012-03-25 14:20:43 +00:00
Scott Long
6ac6f295b0 Final pass at having devices use their bus parent for dma tags. The
remaining drivers that haven't been converted have various problems or
complexities that will be dealt with later.  This list includes:

hptrr, hptmv, hpt27xx - device aggregation across multiple parents
drm - want to talk to the maintainer first
tsec, sec - Openfirmware devices, not sure if changes are warranted
fatm - Done except for unused testing code
usb - want to talk to the maintainer first
ce, cp, ctau, cx - Significant driver changes needed to convey parent info

There are also devices tucked into architecture subtrees that I'll leave
for the respective maintainers to deal with.
2012-03-12 19:29:35 +00:00
Justin T. Gibbs
45cbfcdabc Fix regression in the handling of blkback close events for
devices that are unplugged via QEMU.

sys/dev/xen/blkback/blkback.c:
	Toolstack initiated closures change the frontend's state
	to Closing.  The backend must change to Closing as well,
	even if we can't actually close yet, in order for the
	frontend to notice and start the closing process.

MFC after:	3 days
2012-02-17 22:33:46 +00:00
Justin T. Gibbs
443cc4d407 Fix a bug in the calculation of the maximum I/O request size.
The previous code did not limit the I/O request size based on
the maximum number of segments supported by the back-end.  In
current practice, since the only back-end supporting chained
requests is the FreeBSD implementation, this limit was never
exceeded.

sys/dev/xen/blkfront/block.h:
	Add two macros, XBF_SEGS_TO_SIZE() and XBF_SIZE_TO_SEGS(),
	to centralize the logic of reserving a segment to deal with
	non-page-aligned I/Os.

sys/dev/xen/blkfront/blkfront.c:
	o When negotiating transfer parameters, limit the
	  max_request_size we use and publish, if it is greater
	  than the maximum, unaligned, I/O we can support with
	  the number of segments advertised by the backend.
	o Don't unilaterally reduce the I/O size published to
	  the disk layer by a single page.  max_request_size
	  is already properly limited in the transfer parameter
	  negotiation code.
	o Fix typos in printf strings:
		"max_requests_segments" -> "max_request_segments"
		"specificed" -> "specified"

MFC after:	1 day
2012-02-16 21:58:47 +00:00
Justin T. Gibbs
e6fe91b5e4 Fix typo in a printf string: "specificed" -> "specified".
MFC after:	1 day
2012-02-16 21:49:28 +00:00
Justin T. Gibbs
8b8bfa3567 Enhance documentation, improve interoperability, and fix defects in
FreeBSD's front and back Xen blkif interface drivers.

sys/dev/xen/blkfront/block.h:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkback/blkback.c:
	Replace FreeBSD specific multi-page ring impelementation with
	support for both the Citrix and Amazon/RedHat versions of this
	extension.

sys/dev/xen/blkfront/blkfront.c:
	o Add a per-instance sysctl tree that exposes all negotiated
	  transport parameters (ring pages, max number of requests,
	  max request size, max number of segments).
	o In blkfront_vdevice_to_unit() add a missing return statement
	  so that we properly identify the unit number for high numbered
	  xvd devices.

sys/dev/xen/blkback/blkback.c:
	o Add static dtrace probes for several events in this driver.
	o Defer connection shutdown processing until the front-end
	  enters the closed state.  This avoids prematurely tearing
	  down the connection when buggy front-ends transition to the
	  closing state, even though the device is open and they
	  veto the close request from the tool stack.
	o Add nodes for maximum request size and the number of active
	  ring pages to the exising, per-instance, sysctl tree.
	o Miscelaneous style cleanup.

sys/xen/interface/io/blkif.h:
	o Add extensive documentation of the XenStore nodes used to
	  implement the blkif interface.
	o Document the startup sequence between a front and back driver.
	o Add structures and documenatation for the "discard" feature
	  (AKA Trim).
	o Cleanup some definitions related to FreeBSD's request
	  number/size/segment-limit extension.

sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkback/blkback.c:
sys/xen/xenbus/xenbusvar.h:
	Add the convenience function xenbus_get_otherend_state() and
	use it to simplify some logic in both block-front and block-back.

MFC after:	1 day
2012-02-15 06:45:49 +00:00
Kenneth D. Merry
048a50f354 Fix the netback driver build for i386.
netback.c:	Add missing VM includes.

xen/xenvar.h,
xen/xenpmap.h:	Move some XENHVM macros from <machine/xen/xenpmap.h> to
		<machine/xen/xenvar.h> on i386 to match the amd64 headers.

conf/files:	Add netback to the build.

Submitted by:	jhb
MFC after:	3 days
2012-02-02 17:54:35 +00:00
Kenneth D. Merry
7e949c467c Xen netback driver rewrite.
share/man/man4/Makefile,
share/man/man4/xnb.4,
sys/dev/xen/netback/netback.c,
sys/dev/xen/netback/netback_unit_tests.c:

	Rewrote the netback driver for xen to attach properly via newbus
	and work properly in both HVM and PVM mode (only HVM is tested).
	Works with the in-tree FreeBSD netfront driver or the Windows
	netfront driver from SuSE.  Has not been extensively tested with
	a Linux netfront driver.  Does not implement LRO, TSO, or
	polling.  Includes unit tests that may be run through sysctl
	after compiling with XNB_DEBUG defined.

sys/dev/xen/blkback/blkback.c,
sys/xen/interface/io/netif.h:

	Comment elaboration.

sys/kern/uipc_mbuf.c:

	Fix page fault in kernel mode when calling m_print() on a
	null mbuf.  Since m_print() is only used for debugging, there
	are no performance concerns for extra error checking code.

sys/kern/subr_scanf.c:

	Add the "hh" and "ll" width specifiers from C99 to scanf().
	A few callers were already using "ll" even though scanf()
	was handling it as "l".

Submitted by:	Alan Somers <alans@spectralogic.com>
Submitted by:	John Suykerbuyk <johns@spectralogic.com>
Sponsored by:	Spectra Logic
MFC after:	1 week
Reviewed by:	ken
2012-01-26 16:35:09 +00:00
Colin Percival
206d503b92 Make XENHVM work on i386. The __ffs() function counts bits starting from
zero, unlike ffs(3), which starts counting from 1.
2012-01-16 02:38:45 +00:00
Kevin Lo
5bbe0c5357 ether_ifattach() sets if_mtu to ETHERMTU, don't bother set it again
Reviewed by:	yongari
2012-01-07 09:41:57 +00:00
Andriy Gapon
9976156f12 kern cons: introduce infrastructure for console grabbing by kernel
At the moment grab and ungrab methods of all console drivers are no-ops.

Current intended meaning of the calls is that the kernel takes control of
console input.  In the future the semantics may be extended to mean that
the calling thread takes full ownership of the console (e.g. console
output from other threads could be suspended).

Inspired by:	bde
MFC after:	2 months
2011-12-17 15:08:43 +00:00
Ed Schouten
75da3c1a9b Replace inline static' by static inline'.
If I interpret the C standard correctly, the storage specifier should be
placed before the inline keyword. While at it, replace __inline by
inline in the files affected.
2011-12-13 14:06:01 +00:00
Marius Strobl
4b7ec27007 - There's no need to overwrite the default device method with the default
one. Interestingly, these are actually the default for quite some time
  (bus_generic_driver_added(9) since r52045 and bus_generic_print_child(9)
  since r52045) but even recently added device drivers do this unnecessarily.
  Discussed with: jhb, marcel
- While at it, use DEVMETHOD_END.
  Discussed with: jhb
- Also while at it, use __FBSDID.
2011-11-22 21:28:20 +00:00
Ed Schouten
6472ac3d8a Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.
The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.
2011-11-07 15:43:11 +00:00
Ed Schouten
d745c852be Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.
This means that their use is restricted to a single C file.
2011-11-07 06:44:47 +00:00
Alan Cox
703dec68bf Eliminate vestiges of page coloring in VM_ALLOC_NOOBJ calls to
vm_page_alloc().  While I'm here, for the sake of consistency, always
specify the allocation class, such as VM_ALLOC_NORMAL, as the first of
the flags.
2011-10-27 16:39:17 +00:00
Justin T. Gibbs
578e4bf777 Update netfront so that it queries and honors published
back-end features.

sys/dev/xen/netfront/netfront.c:
	o Add xn_query_features() which reads the XenStore and
	  records the TSO, LRO, and chained ring-request support
	  of the backend.
	o Rename xn_configure_lro() to xn_configure_features() and
	  use this routine to manage the setup of TSO, LRO, and
	  checksum offload.
	o In create_netdev(), initialize if_capabilities and
	  if_hwassist to the capabilities found on all backends.
	  Delegate configuration of if_capenable and the TSO flag
	  if if_hwassist to xn_configure_features().

Reported by:	Hugo Silva (fix inspired by patch provided)
Approved by:	re
MFC after:	1 week
2011-09-21 00:15:29 +00:00
Justin T. Gibbs
ffa06904b5 Modify the netfront driver so it can successfully attach to
PV devices with the ioemu attribute set.

sys/dev/xen/netfront/netfront.c:
	o If a mac address for the interface cannot be found
	  in the front-side XenStore tree, look for an entry
	  in the back-side tree.  With ioemu devices, the
	  emulator does not populate the front side tree and
	  neither does Xend.
	o Return an error rather than panic when an attach
	  attempt fails.

Reported by:	Janne Snabb (fix inspired by patch provided)
PR:		kern/154302
Approved by:	re
2011-09-21 00:13:04 +00:00
Justin T. Gibbs
cf9c09e1f3 Correct suspend/resume support in the Netfront driver.
Sponsored by: BQ Internet

sys/dev/xen/netfront/netfront.c:
	o Implement netfront_suspend(), a specialized suspend
	  handler for the netfront driver.  This routine simply
	  disables the carrier so the driver is idle during
	  system suspend processing.
	o Fix a leak when re-initializing LRO during a link reset.
	o In netif_release_tx_bufs(), when cleaning up the grant
	  references for our TX ring, use gnttab_end_foreign_access_ref
	  instead of attempting to grant the page again.
	o In netif_release_tx_bufs(), we do not track mbufs associated
	  with mbuf chains, but instead just free each mbuf directly.
	  Use m_free(), not m_freem(), to avoid double frees of mbufs.
	o Refactor some code to enhance clarity.

Approved by:	re
MFC after:	1 week
2011-09-21 00:08:25 +00:00
Justin T. Gibbs
06a630f65d Add suspend/resume support to the Xen blkfront driver.
Sponsored by: BQ Internet

sys/dev/xen/blkfront/block.h:
sys/dev/xen/blkfront/blkfront.c:
	Remove now unused blkif_vdev_t from the blkfront soft.

sys/dev/xen/blkfront/blkfront.c:
	o In blkfront_suspend(), indicate the desire to suspend
	  by changing the softc connected state to SUSPENDED, and
	  then wait for any I/O pending on the remote peer to
	  drain.  Cancel suspend processing if I/O does not
	  drain within 30 seconds.
	o Enable and update blkfront_resume().  Since I/O is
	  drained prior to the suspension of the VM, the complicated
	  recovery process performed by other Xen blkfront
	  implementations is avoided.  We simply tear down the
	  connection to our old peer, and then re-connect.
	o In blkif_initialize(), fix a resource leak and botched
	  return if we cannot allocate shadow memory for our
	  requests.
	o In blkfront_backend_changed(), correct our response to
	  the XenbusStateInitialised state.  This state indicates
	  that our backend peer has published sufficient data for
	  blkfront to publish ring information and other XenStore
	  data, not that a connection can occur.  Blkfront now
	  will only perform connection processing in response to
	  the XenbusStateConnected state.  This corrects an issue
	  where blkfront connected before the backend was ready
	  during resume processing.

Approved by:	re
MFC after:	1 week
2011-09-21 00:02:44 +00:00
Justin T. Gibbs
2ca7463bc7 Properly handle suspend/resume events in the Xen device
framework.

Sponsored by:	BQ Internet

sys/xen/xenbus/xenbusb.c:
	o In xenbusb_resume(), publish the state transition of the
	  resuming device into XenbusStateIntiailising so that the
	  remote peer can see it.  Recording the state locally is
	  not sufficient to trigger a re-connect sequence.
	o In xenbusb_resume(), defer new-bus resume processing until
	  after the remote peer's XenStore address has been updated.
	  The drivers may need to refer to this information during
	  resume processing.

sys/xen/xenbus/xenbusb_back.c:
sys/xen/xenbus/xenbusb_front.c:
	Register xenbusb_resume() rather than bus_generic_resume()
	as the handler for device_resume events.

sys/xen/xenstore/xenstore.c:
	o Fix grammer in a comment.
	o In xs_suspend(), pass suspend events on to the child
	  devices (e.g. xenbusb_front/back, that are attached
	  to the XenStore.

Approved by:	re
MFC after:	1 week
2011-09-20 23:44:34 +00:00
Robert Watson
e53e8455f0 Add support for alternative break-to-debugger support on the Xen console.
This should help debug boot-time hangs experienced in 9.0-BETA.

MFC after:	3 weeks
Tested by:	sbruno
Approved by:	re (kib)
2011-09-02 17:36:01 +00:00
Attilio Rao
49f5aeaf41 MFC 2011-06-15 07:20:22 +00:00
Justin T. Gibbs
8a8a3387fd Several enhancements to the Xen block back driver.
sys/dev/xen/blkback/blkback.c:
	o Implement front-end request coalescing.  This greatly improves the
	  performance of front-end clients that are unaware of the dynamic
	  request-size/number of requests negotiation available in the
	  FreeBSD backend driver.  This required a large restructuring
	  in how this driver records in-flight transactions and how those
	  transactions are mapped into kernel KVA.  For example, the driver
	  now includes a mini "KVA manager" that allocates ranges of
	  contiguous KVA to patches of requests that are physically
	  contiguous in the backing store so that a single bio or UIO
	  segment can be used to represent the I/O.

	o Refuse to open any backend files or devices if the system
	  has yet to mount root.  This avoids a panic.

	o Properly handle "onlined" devices.  An "onlined" backend
	  device stays attached to its backing store across front-end
	  disconnections.  This feature is intended to reduce latency
	  when a front-end does a hand-off to another driver (e.g.
	  PV aware bootloader to OS kernel) or during a VM reboot.

	o Harden the driver against a pathological/buggy front-end
	  by carefully vetting front-end XenStore data such as the
	  front-end state.

	o Add sysctls that report the negotiated number of
	  segments per-request and the number of requests that
	  can be concurrently in flight.

Submitted by:	kdm
Reviewed by:	gibbs
Sponsored by:	Spectra Logic Corporation
MFC after:	1 week
2011-06-13 20:36:29 +00:00
Attilio Rao
a38f1f263b Remove pc_cpumask and pc_other_cpus usage from MI code.
Tested by:	pluknet
2011-06-13 13:28:31 +00:00
Justin T. Gibbs
283d6f7287 Monitor and emit events for XenStore changes to XenBus trees
of the devices we manage.  These changes can be due to writes
we make ourselves or due to changes made by the control domain.
The goal of these changes is to insure that all state transitions
can be detected regardless of their source and to allow common
device policies (e.g. "onlined" backend devices) to be centralized
in the XenBus bus code.

sys/xen/xenbus/xenbusvar.h:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbus_if.m:
	Add a new method for XenBus drivers "localend_changed".
	This method is invoked whenever a write is detected to
	a device's XenBus tree.  The default implementation of
	this method is a no-op.

sys/xen/xenbus/xenbus_if.m:
sys/dev/xen/netfront/netfront.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkback/blkback.c:
	Change the signature of the "otherend_changed" method.
	This notification cannot fail, so it should return void.

sys/xen/xenbus/xenbusb_back.c:
	Add "online" device handling to the XenBus Back Bus
	support code.  An online backend device remains active
	after a front-end detaches as a reconnect is expected
	to occur in the near future.

sys/xen/interface/io/xenbus.h:
	Add comment block further explaining the meaning and
	driver responsibilities associated with the XenBus
	Closed state.

sys/xen/xenbus/xenbusb.c:
sys/xen/xenbus/xenbusb.h:
sys/xen/xenbus/xenbusb_back.c:
sys/xen/xenbus/xenbusb_front.c:
sys/xen/xenbus/xenbusb_if.m:
	o Register a XenStore watch against the local XenBus tree
	  for all devices.
	o Cache the string length of the path to our local tree.
	o Allow the xenbus front and back drivers to hook/filter both
	  local and otherend watch processing.
	o Update the device ivar version of "state" when we detect
	  a XenStore update of that node.

sys/dev/xen/control/control.c:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbusb.c:
sys/xen/xenbus/xenbusb.h:
sys/xen/xenbus/xenbusvar.h:
sys/xen/xenstore/xenstorevar.h:
	Allow clients of the XenStore watch mechanism to attach
	a single uintptr_t worth of client data to the watch.
	This removes the need to carefully place client watch
	data within enclosing objects so that a cast or offsetof
	calculation can be used to convert from watch to enclosing
	object.

Sponsored by:	Spectra Logic Corporation
MFC after:	1 week
2011-06-11 04:59:01 +00:00
Attilio Rao
739e31f6d7 MFC 2011-05-13 15:20:57 +00:00
Alexander Motin
c4f9a10590 Fix msleep() usage in Xen balloon driver to not wake up on every HZ tick. 2011-05-13 03:40:16 +00:00
Attilio Rao
71a19bdc64 Commit the support for removing cpumask_t and replacing it directly with
cpuset_t objects.
That is going to offer the underlying support for a simple bump of
MAXCPU and then support for number of cpus > 32 (as it is today).

Right now, cpumask_t is an int, 32 bits on all our supported architecture.
cpumask_t on the other side is implemented as an array of longs, and
easilly extendible by definition.

The architectures touched by this commit are the following:
- amd64
- i386
- pc98
- arm
- ia64
- XEN

while the others are still missing.
Userland is believed to be fully converted with the changes contained
here.

Some technical notes:
- This commit may be considered an ABI nop for all the architectures
  different from amd64 and ia64 (and sparc64 in the future)
- per-cpu members, which are now converted to cpuset_t, needs to be
  accessed avoiding migration, because the size of cpuset_t should be
  considered unknown
- size of cpuset_t objects is different from kernel and userland (this is
  primirally done in order to leave some more space in userland to cope
  with KBI extensions). If you need to access kernel cpuset_t from the
  userland please refer to example in this patch on how to do that
  correctly (kgdb may be a good source, for example).
- Support for other architectures is going to be added soon
- Only MAXCPU for amd64 is bumped now

The patch has been tested by sbruno and Nicholas Esborn on opteron
4 x 12 pack CPUs. More testing on big SMP is expected to came soon.
pluknet tested the patch with his 8-ways on both amd64 and i386.

Tested by:	pluknet, sbruno, gianni, Nicholas Esborn
Reviewed by:	jeff, jhb, sbruno
2011-05-05 14:39:14 +00:00
Bjoern A. Zeeb
a0ae8f04e8 Make various (pseudo) interfaces compile without INET in the kernel
adding appropriate #ifdefs.  For module builds the framework needs
adjustments for at least carp.

Reviewed by:	gnn
Sponsored by:	The FreeBSD Foundation
Sponsored by:	iXsystems
MFC after:	4 days
2011-04-27 19:30:44 +00:00
Justin T. Gibbs
8577146eac Fix bug in the netfront driver that caused excessive packet drops during
receive processing.

Remove unnecessary restrictions on the mbuf chain length built during an
LRO receive.  This restriction was copied from the Linux netfront driver
where the LRO implementation cannot handle more than 18 discontinuities.
The FreeBSD implementation has no such restriction.

MFC after: 1 week
2011-01-29 02:36:45 +00:00
Matthew D Fleming
f4f04709ac Fix a few more SYSCTL_PROC() that were missing a CTLFLAG type specifier. 2011-01-19 00:57:58 +00:00
Robert Watson
2913e88c91 Make "options XENHVM" compile for i386, not just amd64 -- a largely
mechanical change.  This opens the door for using PV device drivers
under Xen HVM on i386, as well as more general harmonisation of i386
and amd64 Xen support in FreeBSD.

Reviewed by:    cperciva
MFC after:      3 weeks
2011-01-04 14:49:54 +00:00
Colin Percival
eb68ccd676 A lack of console input is not the same thing as a byte of \0 input.
Correctly return -1 from cngetc when no input is available to be read.

This fixes the '(CTRL-C to abort)' spam while dumping.

MFC after:	3 days
2010-12-29 05:13:21 +00:00
Colin Percival
518c824362 Set correct maximum I/O length. We can only handle I/O of up to
max_request_segments * PAGE_SIZE if the I/O is page-aligned; the
largest I/O we can guarantee will work is PAGE_SIZE less than that.
This unbreaks 'diskinfo -t'.
2010-12-06 20:40:15 +00:00
Justin T. Gibbs
8f1382d1f2 sys/dev/xen/blkback/blkback.c:
In xbb_detach() only perform cleanup of our taskqueue and
	device statistics structures if they have been initialized.
	This avoids a panic when xbb_detach() is called on a partially
	initialized device instance, due to an early failure in
	attach.

Sponsored by:	Spectra Logic Corporation
2010-10-28 04:14:28 +00:00
Justin T. Gibbs
ff662b5c98 Improve the Xen para-virtualized device infrastructure of FreeBSD:
o Add support for backend devices (e.g. blkback)
 o Implement extensions to the Xen para-virtualized block API to allow
   for larger and more outstanding I/Os.
 o Import a completely rewritten block back driver with support for fronting
   I/O to both raw devices and files.
 o General cleanup and documentation of the XenBus and XenStore support code.
 o Robustness and performance updates for the block front driver.
 o Fixes to the netfront driver.

Sponsored by: Spectra Logic Corporation

sys/xen/xenbus/init.txt:
	Deleted: This file explains the Linux method for XenBus device
	enumeration and thus does not apply to FreeBSD's NewBus approach.

sys/xen/xenbus/xenbus_probe_backend.c:
	Deleted: Linux version of backend XenBus service routines.  It
	was never ported to FreeBSD.  See xenbusb.c, xenbusb_if.m,
	xenbusb_front.c xenbusb_back.c for details of FreeBSD's XenBus
	support.

sys/xen/xenbus/xenbusvar.h:
sys/xen/xenbus/xenbus_xs.c:
sys/xen/xenbus/xenbus_comms.c:
sys/xen/xenbus/xenbus_comms.h:
sys/xen/xenstore/xenstorevar.h:
sys/xen/xenstore/xenstore.c:
	Split XenStore into its own tree.  XenBus is a software layer built
	on top of XenStore.  The old arrangement and the naming of some
	structures and functions blurred these lines making it difficult to
	discern what services are provided by which layer and at what times
	these services are available (e.g. during system startup and shutdown).

sys/xen/xenbus/xenbus_client.c:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbus_probe.c:
sys/xen/xenbus/xenbusb.c:
sys/xen/xenbus/xenbusb.h:
	Split up XenBus code into methods available for use by client
	drivers (xenbus.c) and code used by the XenBus "bus code" to
	enumerate, attach, detach, and service bus drivers.

sys/xen/reboot.c:
sys/dev/xen/control/control.c:
	Add a XenBus front driver for handling shutdown, reboot, suspend, and
	resume events published in the XenStore.  Move all PV suspend/reboot
	support from reboot.c into this driver.

sys/xen/blkif.h:
	New file from Xen vendor with macros and structures used by
	a block back driver to service requests from a VM running a
	different ABI (e.g. amd64 back with i386 front).

sys/conf/files:
	Adjust kernel build spec for new XenBus/XenStore layout and added
	Xen functionality.

sys/dev/xen/balloon/balloon.c:
sys/dev/xen/netfront/netfront.c:
sys/dev/xen/blkfront/blkfront.c:
sys/xen/xenbus/...
sys/xen/xenstore/...
	o Rename XenStore APIs and structures from xenbus_* to xs_*.
	o Adjust to use of M_XENBUS and M_XENSTORE malloc types for allocation
	  of objects returned by these APIs.
	o Adjust for changes in the bus interface for Xen drivers.

sys/xen/xenbus/...
sys/xen/xenstore/...
	Add Doxygen comments for these interfaces and the code that
	implements them.

sys/dev/xen/blkback/blkback.c:
	o Rewrite the Block Back driver to attach properly via newbus,
	  operate correctly in both PV and HVM mode regardless of domain
	  (e.g. can be in a DOM other than 0), and to deal with the latest
	  metadata available in XenStore for block devices.

	o Allow users to specify a file as a backend to blkback, in addition
	  to character devices.  Use the namei lookup of the backend path
	  to automatically configure, based on file type, the appropriate
	  backend method.

	The current implementation is limited to a single outstanding I/O
	at a time to file backed storage.

sys/dev/xen/blkback/blkback.c:
sys/xen/interface/io/blkif.h:
sys/xen/blkif.h:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
	Extend the Xen blkif API: Negotiable request size and number of
	requests.

	This change extends the information recorded in the XenStore
	allowing block front/back devices to negotiate for optimal I/O
	parameters.  This has been achieved without sacrificing backward
	compatibility with drivers that are unaware of these protocol
	enhancements.  The extensions center around the connection protocol
	which now includes these additions:

	o The back-end device publishes its maximum supported values for,
	  request I/O size, the number of page segments that can be
	  associated with a request, the maximum number of requests that
	  can be concurrently active, and the maximum number of pages that
	  can be in the shared request ring.  These values are published
	  before the back-end enters the XenbusStateInitWait state.

	o The front-end waits for the back-end to enter either the InitWait
	  or Initialize state.  At this point, the front end limits it's
	  own capabilities to the lesser of the values it finds published
	  by the backend, it's own maximums, or, should any back-end data
	  be missing in the store, the values supported by the original
	  protocol.  It then initializes it's internal data structures
	  including allocation of the shared ring, publishes its maximum
	  capabilities to the XenStore and transitions to the Initialized
	  state.

	o The back-end waits for the front-end to enter the Initalized
	  state.  At this point, the back end limits it's own capabilities
	  to the lesser of the values it finds published by the frontend,
	  it's own maximums, or, should any front-end data be missing in
	  the store, the values supported by the original protocol.  It
	  then initializes it's internal data structures, attaches to the
	  shared ring and transitions to the Connected state.

	o The front-end waits for the back-end to enter the Connnected
	  state, transitions itself to the connected state, and can
	  commence I/O.

	Although an updated front-end driver must be aware of the back-end's
	InitWait state, the back-end has been coded such that it can
	tolerate a front-end that skips this step and transitions directly
	to the Initialized state without waiting for the back-end.

sys/xen/interface/io/blkif.h:
	o Increase BLKIF_MAX_SEGMENTS_PER_REQUEST to 255.  This is
	  the maximum number possible without changing the blkif
	  request header structure (nr_segs is a uint8_t).

	o Add two new constants:
	  BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK, and
	  BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK.  These respectively
	  indicate the number of segments that can fit in the first
	  ring-buffer entry of a request, and for each subsequent
	  (sg element only) ring-buffer entry associated with the
          "header" ring-buffer entry of the request.

	o Add the blkif_request_segment_t typedef for segment
	  elements.

	o Add the BLKRING_GET_SG_REQUEST() macro which wraps the
	  RING_GET_REQUEST() macro and returns a properly cast
	  pointer to an array of blkif_request_segment_ts.

	o Add the BLKIF_SEGS_TO_BLOCKS() macro which calculates the
	  number of ring entries that will be consumed by a blkif
	  request with the given number of segments.

sys/xen/blkif.h:
	o Update for changes in interface/io/blkif.h macros.

	o Update the BLKIF_MAX_RING_REQUESTS() macro to take the
	  ring size as an argument to allow this calculation on
	  multi-page rings.

	o Add a companion macro to BLKIF_MAX_RING_REQUESTS(),
	  BLKIF_RING_PAGES().  This macro determines the number of
	  ring pages required in order to support a ring with the
	  supplied number of request blocks.

sys/dev/xen/blkback/blkback.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
	o Negotiate with the other-end with the following limits:
	      Reqeust Size:   MAXPHYS
	      Max Segments:   (MAXPHYS/PAGE_SIZE) + 1
	      Max Requests:   256
	      Max Ring Pages: Sufficient to support Max Requests with
	                      Max Segments.

	o Dynamically allocate request pools and segemnts-per-request.

	o Update ring allocation/attachment code to support a
	  multi-page shared ring.

	o Update routines that access the shared ring to handle
	  multi-block requests.

sys/dev/xen/blkfront/blkfront.c:
	o Track blkfront allocations in a blkfront driver specific
	  malloc pool.

	o Strip out XenStore transaction retry logic in the
	  connection code.  Transactions only need to be used when
	  the update to multiple XenStore nodes must be atomic.
	  That is not the case here.

	o Fully disable blkif_resume() until it can be fixed
	  properly (it didn't work before this change).

	o Destroy bus-dma objects during device instance tear-down.

	o Properly handle backend devices with powef-of-2 sector
	  sizes larger than 512b.

sys/dev/xen/blkback/blkback.c:
	Advertise support for and implement the BLKIF_OP_WRITE_BARRIER
	and BLKIF_OP_FLUSH_DISKCACHE blkif opcodes using BIO_FLUSH and
	the BIO_ORDERED attribute of bios.

sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
	Fix various bugs in blkfront.

       o gnttab_alloc_grant_references() returns 0 for success and
	 non-zero for failure.  The check for < 0 is a leftover
	 Linuxism.

       o When we negotiate with blkback and have to reduce some of our
	 capabilities, print out the original and reduced capability before
	 changing the local capability.  So the user now gets the correct
	 information.

	o Fix blkif_restart_queue_callback() formatting.  Make sure we hold
	  the mutex in that function before calling xb_startio().

	o Fix a couple of KASSERT()s.

        o Fix a check in the xb_remove_* macro to be a little more specific.

sys/xen/gnttab.h:
sys/xen/gnttab.c:
	Define GNTTAB_LIST_END publicly as GRANT_REF_INVALID.

sys/dev/xen/netfront/netfront.c:
	Use GRANT_REF_INVALID instead of driver private definitions of the
	same constant.

sys/xen/gnttab.h:
sys/xen/gnttab.c:
	Add the gnttab_end_foreign_access_references() API.

	This API allows a client to batch the release of an array of grant
	references, instead of coding a private for loop.  The implementation
	takes advantage of this batching to reduce lock overhead to one
	acquisition and release per-batch instead of per-freed grant reference.

	While here, reduce the duration the gnttab_list_lock is held during
	gnttab_free_grant_references() operations.  The search to find the
	tail of the incoming free list does not rely on global state and so
	can be performed without holding the lock.

sys/dev/xen/xenpci/evtchn.c:
sys/dev/xen/evtchn/evtchn.c:
sys/xen/xen_intr.h:
	o Implement the bind_interdomain_evtchn_to_irqhandler API for HVM mode.
	  This allows an HVM domain to serve back end devices to other domains.
	  This API is already implemented for PV mode.

	o Synchronize the API between HVM and PV.

sys/dev/xen/xenpci/xenpci.c:
	o Scan the full region of CPUID space in which the Xen VMM interface
	  may be implemented.  On systems using SuSE as a Dom0 where the
	  Viridian API is also exported, the VMM interface is above the region
	  we used to search.

	o Pass through bus_alloc_resource() calls so that XenBus drivers
	  attaching on an HVM system can allocate unused physical address
	  space from the nexus.  The block back driver makes use of this
	  facility.

sys/i386/xen/xen_machdep.c:
	Use the correct type for accessing the statically mapped xenstore
	metadata.

sys/xen/interface/hvm/params.h:
sys/xen/xenstore/xenstore.c:
	Move hvm_get_parameter() to the correct global header file instead
	of as a private method to the XenStore.

sys/xen/interface/io/protocols.h:
	Sync with vendor.

sys/xeninterface/io/ring.h:
	Add macro for calculating the number of ring pages needed for an N
	deep ring.

	To avoid duplication within the macros, create and use the new
	__RING_HEADER_SIZE() macro.  This macro calculates the size of the
	ring book keeping struct (producer/consumer indexes, etc.) that
	resides at the head of the ring.

	Add the __RING_PAGES() macro which calculates the number of shared
	ring pages required to support a ring with the given number of
	requests.

	These APIs are used to support the multi-page ring version of the
	Xen block API.

sys/xeninterface/io/xenbus.h:
	Add Comments.

sys/xen/xenbus/...
	o Refactor the FreeBSD XenBus support code to allow for both front and
	  backend device attachments.

	o Make use of new config_intr_hook capabilities to allow front and back
	  devices to be probed/attached in parallel.

	o Fix bugs in probe/attach state machine that could cause the system to
	  hang when confronted with a failure either in the local domain or in
	  a remote domain to which one of our driver instances is attaching.

	o Publish all required state to the XenStore on device detach and
	  failure.  The majority of the missing functionality was for serving
	  as a back end since the typical "hot-plug" scripts in Dom0 don't
	  handle the case of cleaning up for a "service domain" that is not
	  itself.

	o Add dynamic sysctl nodes exposing the generic ivars of
	  XenBus devices.

	o Add doxygen style comments to the majority of the code.

	o Cleanup types, formatting, etc.

sys/xen/xenbus/xenbusb.c:
	Common code used by both front and back XenBus busses.

sys/xen/xenbus/xenbusb_if.m:
	Method definitions for a XenBus bus.

sys/xen/xenbus/xenbusb_front.c:
sys/xen/xenbus/xenbusb_back.c:
	XenBus bus specialization for front and back devices.

MFC after:	1 month
2010-10-19 20:53:30 +00:00
Kenneth D. Merry
931eeffaa2 A number of netfront fixes and stability improvements:
- Re-enable TSO.  This was broken previously due to CSUM_TSO clearing the
   CSUM_TCP flag, so our checksum flags were incorrectly set going to the
   netback driver.  That was fixed in r206844 in tcp_output.c, so we can
   turn TSO back on here.

 - Fix the way transmit slots are calculated, so that we can't overfill
   the ring.

 - Avoid sending packets with more fragments/segments than netback can
   handle.  The Linux netback code can only handle packets of
   MAX_SKB_FRAGS, which turns out to be 18 on machines with 4K pages.  We
   can easily generate packets with 32 or so fragments with TSO turned on.
   Right now the solution is just to drop the packets (since netback
   doesn't seem to handle it gracefully), but we should come up with a way
   to allow a driver to tell the TCP stack the maximum number of fragments
   it can handle in a single packet.

 - Fix the way the consumer is tracked in the receive path.  It could get
   out of sync fairly easily.

 - Use standard Xen ring macros to make it clearer how netfront is using
   the rings.

 - Get rid of Linux-ish negative errno return values.

 - Added more documentation to the driver.

 - Refactored code to make it easier to read.

 - Some other minor fixes.

Reviewed by:	gibbs

Reviewed by:	gibbs
Sponsored by:	Spectra Logic
MFC after:	7 days
2010-06-08 03:13:26 +00:00
Joel Dahl
8e0ad55abb Switch to our preferred 2-clause BSD license.
Approved by:	kmacy
2010-05-05 20:39:02 +00:00
Randall Stewart
1966e5b5a1 The proper fix for the delayed SCTP checksum is to
have the delayed function take an argument as to the offset
to the SCTP header. This allows it to work for V4 and V6.
This of course means changing all callers of the function
to either pass the header len, if they have it, or create
it (ip_hl << 2 or sizeof(ip6_hdr)).
PR:		144529
MFC after:	2 weeks
2010-03-12 22:58:52 +00:00
Kip Macy
227ca25786 - make printf conditional
- fix witness warnings by making configuration lock a mutex
2010-02-21 01:11:39 +00:00
Justin T. Gibbs
491e647805 In blkif_queue_cb(), test the return value from gnttab_claim_grant_reference()
for >= 0 instead of != ENOSPC.
2009-12-29 23:31:21 +00:00
Justin T. Gibbs
a4660d594f Correct alignment and boundary constraints in blkfront's bus dma tag. The
blkif interface in Xen requires all I/O to be 512 byte aligned with each
segment bounded by a 4k page.

Note: This submission only documents the proper contraints for blkif I/O.
      The alignment code in busdma does not yet handle alignment constraints
      correctly in all cases.
2009-12-28 18:59:13 +00:00
Justin T. Gibbs
0e5098428f Add media ioctl support and link notifications so that devd will attempt
to run dhclient on a netfront (xn) device that is setup for DHCP in
/etc/rc.conf.

PR:		kern/136251 (fixed differently than the submitted patch)
2009-12-01 17:29:25 +00:00
Kip Macy
e4808c4b2d Merge Scott Long's latest blkfront now that the licensing issues are resolved 2009-11-30 04:32:34 +00:00
Kip Macy
9999d2cb72 Update license to reflect terms in xen 2.0 as of the time when the driver was ported
to FreeBSD
2009-11-30 04:20:43 +00:00
Kip Macy
2036720ba9 remove annoying printf that cripples kdb on PV guests 2009-11-24 07:18:38 +00:00
Kip Macy
be7747b449 fixup kernel core dumps on paravirtual guests 2009-11-24 07:17:51 +00:00
John Baldwin
dbd69bc565 Remove commented out reference to if_watchdog and an assignment of zero to
if_timer.

Reviewed by:	scottl
2009-11-19 20:59:40 +00:00
Kip Macy
8698b76c3d add core dump support to blkfront
Obtained from:	Frank Suchomel
2009-08-30 20:45:24 +00:00