of proper value. It caused bunch of "EMPTY CRPB" messages and potentially
may cause premature requests completion, which could cause data corruption.
For most cases it seems enough to just reread register to get proper value.
To protect against worse cases - erase processed queue entries with
impossible values and ignore them if problem still happen.
released a drver lock for shared interrupt case such that it caused
panic. While I'm here check whether driver is still running before
serving TX/RX handler.
Reported by: Jerahmy Pocott < QUAKENET1 <> optusnet dot com dot au >
Tested by: Jerahmy Pocott < QUAKENET1 <> optusnet dot com dot au >
MFC after: 3 days
receive two back-to-back send BDs with less than or equal to 8
total bytes then the device may hang. The two back-to-back send
BDs must be in the same frame for this failure to occur.
Thanks to davidch for detailed errata information.
Reviewed by: davidch
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
added with hw.pci.do_powerstate but the PCI version was splitted into two
separate tunables later and now this is completely stale. To make it worse,
PCI devices enumerated in ACPI tree ignore this tunable as it is handled by
a function in acpi_pci.c instead.
knowledges from the file. All PCI devices enumerated in ACPI tree must use
correct one from acpi_pci.c any way. Reduce duplicate codes as we did for
pci.c in r213905. Do not return ESRCH from PCIB_POWER_FOR_SLEEP method.
When the method is not found, just return zero without modifying the given
default value as it is completely optional. As a side effect, the return
state must not be NULL. Note there is actually no functional change by
removing ESRCH because acpi_pcib_power_for_sleep() always returns zero.
Adjust debugging messages and add new ones under bootverbose to help
debugging device power state related issues.
Reviewed by: jhb, imp (earlier versions)
a critical section as apparently required by both. I don't think either
belongs in the event timer front-ends but the callback should handle
this as necessary instead just like for example intr_event_handle()
does but this is how the other architectures currently handle it, either
explicitly or implicitly.
- Further rename and reword references to hardclock as this front-end no
longer has a notion of actually calling it.
This can happen if the algos are built as modules but are not loaded. If
the selected ratectl algo is not available, try to load it (The load
module functions does nothing currently). Add a dummy ratectl algo which
always selects the first available rate. Use that one if the desired algo
is not available.
MFC after: 1 week
and print a diagnostic if the call fails.
This avoids a panic when a device with an invalid name is attempted to
be registered. For example the label class gets device names from
untrusted input.
Reviewed by: freebsd-geom
not support VFS_VGET, like msdosfs, do not call VOP_LOOKUP() for
dotdot on the root directory. Our filesystems expect that VFS handles
dotdot lookups on root on its own.
Reported and tested by: kevlo
MFC after: 2 weeks
by both clients. Since the NLM uses various fields of the
nfsmount structure, those fields were extracted and put in a
separate nfs_mountcommon structure stored in sys/nfs/nfs_mountcommon.h.
This structure also has a function pointer for a function that
extracts the required information from the mount point and nfs vnode
for that particular client, for information stored differently by the
clients.
Reviewed by: jhb
MFC after: 2 weeks
fixed the issues with file descriptor locks, but the same problems are
present for vnode lock/user map lock.
If the nfs_asyncio() cannot find the free nfsiod, schedule task to
create new nfsiod and return error. This causes fall back to the
synchronous i/o for nfs_strategy(), or does not start read at all in
the case of readahead. The caller that holds vnode and potentially
user map lock does not wait for kproc_create() to finish, preventing
the LORs.
The change effectively reverts r203072, because we never hand off the
request to newly created nfsiod thread anymore.
Reviewed by: jhb
Tested by: jhb, pluknet
MFC after: 3 weeks
- Implement proper combined mode decoding for Intel controllers to properly
identify SATA and PATA channels and associate ATA channels with SATA ports.
This fixes wrong reporting and in some cases hard resets to wrong SATA ports.
- Improve SATA registers support to handle hot-plug events and potentially
interface errors. For ICH5/6300ESB chipsets these registers accessible via
PCI config space. For later ones they may be accessible via PCI BAR(5).
- For controllers not generating interrupts on hot-plug events, implement
periodic status polling. Use it to detect hot-plug on Intel and VIA
controllers. Same probably could also be used for Serverworks and SIS.
root file system (starting with devfs and a synthesized configuration) can
contain directives for mounting another file system as root. The old root
file system is re-mounted under the new root file system (with /.mount or
/mnt as the mount point) to allow access to the underlying file system.
The configuration allows for creating vnode-backed memory disks that can
subsequently be mounted as root. This allows for an efficient and low-
cost way to distribute and boot FreeBSD software images that reside on
some storage media.
When trying a mount, the kernel will wait for the device in question to
arrive. The timeout is configurable and is part of the configuration.
This allows arbitrarily complex GEOM configurations to be constructed
on the fly.
A side-effect of this change is that all root specifications, whether
compiled into the kernel or typed at the prompt can contain root mount
options.
To protect against malicious software, we demand that the file name is at
a particular location (i.e. appended to the mdio structure) for it to be
treated as in-kernel.
counter on SMU-based systems, which causes FreeBSD to reject the RTC time
when used in a dual-boot environment. Since we don't use the day-of-week
counter anyway, solve this by just not checking that it matches.
MFC after: 3 weeks
drift in order to achieve a more stable clock as the tick intervals may
vary in the first place. In fact I haven't seen this code kick in when
in oneshot-mode so just skip it in that case.
- There's no need to explicitly stop the (S)TICK counter in oneshot-mode
with every tick as it just won't trigger again with the (S)TICK compare
register set to a value in the past (with a wrap-around once every ~195
years of uptime at 1.5 GHz this isn't something we have to worry about
in practice).
- Given that we'll disable interrupts completely anyway there's no
need to enter critical sections.
- In thr_exit() and kthread_exit(), only remove thread from
hash if it can directly exit, otherwise let exit1() do it.
- In thread_suspend_check(), fix cleanup code when thread needs
to exit.
This change seems fixed the "Bad link elm " panic found by
Peter Holm.
Stress testing: pho
This should make vnode_pager_getpages path a bit shorter and clearer.
Also this should eliminate problems with partially valid pages.
Having this method opens room for future optimizations.
To do: try to satisfy other pages besides the required one taking into
account tradeofs between number of page faults, read throughput and read
latency. Also, eventually vop_putpages should be added too.
Reviewed by: kib, mm, pjd
MFC after: 3 weeks
Make it harder to exploit certain in_control() related races between the
intiial lookup at the beginning and the time we will remove the entry
from the lists by re-checking that entry is still in the list before
trying to remove it.
(*) It is believed that with the current code and locking strategy we
cannot completely fix all race.
Reported by: Nima Misaghian (nima_misa hotmail.com) on net@ 20100817
Tested by: Nima Misaghian (nima_misa hotmail.com) (original version)
PR: kern/146250
Submitted by: Mikolaj Golub (to.my.trociny gmail.com) (different version)
MFC after: 1 week
important for USB 2.0 devices and some of them reported to have problems
with large transactions. But USB 3.0 benchmarks show that limited number
of transactions per second on USB makes impossible to reach high transfer
speeds without using bigger transactions.
On my tests this change allows to read up to 220MB/s from USB-attached SSD
(at block size of 256-512KB), comparing to only 113MB/s without it.
Reviewed by: hselasky
over all interfaces to make sure the address will neither change nor be
freed while we are working on it.
PR: kern/146250
Submitted by: Mikolaj Golub (to.my.trociny gmail.com)
MFC after: 1 week
Old scrolls tell that once upon a time IBM AT BIOS was known to put some
useful system diagnostic information into RTC NVRAM. It is not really
known if and for how long PC BIOSes followed that convention, but I
believe that many, if not all, modern BIOSes do not do that any more
(not mentioning other types of x86 firmware).
Some diagnostic bits don't even make any sense any longer.
The check results in confusing messages upon boot on some systems.
So I am removing it.
Discussed with: bde, jhb, mav
MFC after: 3 weeks
Move debug.ncnegfactor to vfs.ncnegfactor [1].
Provide some descriptions for the namecache related sysctls [1].
Based on the submission by: Rogier R. Mulhuijzen <drwilco drwilco net> [1]
MFC after: 2 weeks
X-MFC-note: remove debug.ncnegfactor in HEAD after MFC
too coarse grained to be useful and the default value significantly degrades TCP
performance on moderate to high bandwidth-delay product paths with non-zero loss
(e.g. 5+Mbps connections across the public Internet often suffer).
Replace the outgoing mechanism with an individual per-queue limit based on the
number of MSS segments that fit into the socket's receive buffer. This should
strike a good balance between performance and the potential for resource
exhaustion when FreeBSD is acting as a TCP receiver. With socket buffer
autotuning (which is enabled by default), the reassembly queue tracks the
socket buffer and benefits too.
As the XXX comment suggests, my testing uncovered some unexpected behaviour
which requires further investigation. By using so->so_rcv.sb_hiwat
instead of sbspace(&so->so_rcv), we allow more segments to be held across both
the socket receive buffer and reassembly queue than we probably should. The
tradeoff is better performance in at least one common scenario, versus a devious
sender's ability to consume more resources on a FreeBSD receiver.
Sponsored by: FreeBSD Foundation
Reviewed by: andre, gnn, rpaulo
MFC after: 2 weeks
