idetape_queue_pc_tail() is a wrapper for its __idetape_queue_pc_tail() counterpart
and has no other functionality. Remove it and call the "wrapped" function
directly.
The computation of the block offset of the the tape position (MTIOCPOS,
MTIOCGET) is not influenced by the stages queued in the pipeline anymore but by
the size of the current buffer which is going to be sent to the drive.
ide-tape: remove pipeline-specific code in idetape_space_over_filemarks()
Since we don't do pipeline read-ahead anymore, we don't have to look for
filemarks we have crossed. Therefore, remove the code chunk that does that and
pass on the command to the tape. As a side effect, remove unused
idetape_wait_first_stage().
ide-tape: remove pipeline-specific code from idetape_add_chrdev_read_request()
In order to do away with queueing read requests on the pipeline, several things
have to be done:
1. Do not allocate additional pipeline stages in idetape_init_read() until
(tape->nr_stages < max_stages) and do only read operation preparations. As a
collateral result, idetape_add_stage_tail() becomes unused so remove it.
2. Queue the read request's buffer directly thru idetape_queue_rw_tail().
3. Remove now unused idetape_kmalloc_stage() and idetape_switch_buffers().
Prior to allocating a new pipeline stage, the code checked for the existence of
a cached pipeline stage to use. Do away with and stick to normal pipeline
stages only.
* "ide_core.ignore_cable=[interface_number]" boot option if IDE is built-in
(i.e. "ide_core.ignore_cable=1" to force ignoring cable for "ide1")
* "ignore_cable=[interface_number]" module parameter (for ide_core module)
if IDE is compiled as module
v2:
* Add ide_port_apply_params() helper
- use it in ide_device_add_all() and ide_scan_port().
* Make it possible to later disable ignoring cable detection by passing
"[interface_number]:0" to /sys/module/ide_core/parameters/ignore_cable
(however sysfs interface is not enabled yet since it needs some other
IDE changes to make it work reliable).
KVM: SVM: add intercept for machine check exception
To properly forward a MCE occured while the guest is running to the host, we
have to intercept this exception and call the host handler by hand. This is
implemented by this patch.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch aligns the host version of the CR4.MCE bit with the CR4 active in
the guest. This is necessary to get MCE exceptions when the guest is running.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Anthony Liguori [Wed, 2 Apr 2008 19:46:56 +0000 (14:46 -0500)]
KVM: MMU: Don't assume struct page for x86
This patch introduces a gfn_to_pfn() function and corresponding functions like
kvm_release_pfn_dirty(). Using these new functions, we can modify the x86
MMU to no longer assume that it can always get a struct page for any given gfn.
We don't want to eliminate gfn_to_page() entirely because a number of places
assume they can do gfn_to_page() and then kmap() the results. When we support
IO memory, gfn_to_page() will fail for IO pages although gfn_to_pfn() will
succeed.
This does not implement support for avoiding reference counting for reserved
RAM or for IO memory. However, it should make those things pretty straight
forward.
Since we're only introducing new common symbols, I don't think it will break
the non-x86 architectures but I haven't tested those. I've tested Intel,
AMD, NPT, and hugetlbfs with Windows and Linux guests.
[avi: fix overflow when shifting left pfns by adding casts]
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
kvm_minstate.h : Marcos about Min save routines.
lapic.h: apic structure definition.
vcpu.h : routions related to vcpu virtualization.
vti.h : Some macros or routines for VT support on Itanium.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
There is no need to use interlocked updates when the rcp
lock is held. Therefore the simple bitops variants can be
used. This should improve performance.
Temporarily rename this function to avoid merge conflicts and/or
dependencies. This function will be removed as soon as git-s390
and kvm.git are finally upstream.
KVM: MMU: prepopulate guest pages after write-protecting
Zdenek reported a bug where a looping "dmsetup status" eventually hangs
on SMP guests.
The problem is that kvm_mmu_get_page() prepopulates the shadow MMU
before write protecting the guest page tables. By doing so, it leaves a
window open where the guest can mark a pte as present while the host has
shadow cached such pte as "notrap". Accesses to such address will fault
in the guest without the host having a chance to fix the situation.
Fix by moving the write protection before the pte prefetch.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Avi Kivity [Thu, 3 Apr 2008 09:02:21 +0000 (12:02 +0300)]
KVM: MMU: Only mark_page_accessed() if the page was accessed by the guest
If the accessed bit is not set, the guest has never accessed this page
(at least through this spte), so there's no need to mark the page
accessed. This provides more accurate data for the eviction algortithm.
Izik Eidus [Sun, 30 Mar 2008 13:01:25 +0000 (16:01 +0300)]
KVM: add vm refcounting
the main purpose of adding this functions is the abilaty to release the
spinlock that protect the kvm list while still be able to do operations
on a specific kvm in a safe way.
Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
The kvm_host.h file for x86 declares the functions kvm_set_cr[0348]. In the
header file their second parameter is named cr0 in all cases. This patch
renames the parameters so that they match the function name.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Sheng Yang [Fri, 28 Mar 2008 05:18:56 +0000 (13:18 +0800)]
KVM: VMX: Enable MSR Bitmap feature
MSR Bitmap controls whether the accessing of an MSR causes VM Exit.
Eliminating exits on automatically saved and restored MSRs yields a
small performance gain.
Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
s390: KVM guest: virtio device support, and kvm hypercalls
This patch implements kvm guest kernel support for paravirtualized devices
and contains two parts:
o a basic virtio stub using virtio_ring and external interrupts and hypercalls
o full hypercall implementation in kvm_para.h
Currently we dont have PCI on s390. Making virtio_pci usable for s390 seems
more complicated that providing an own stub. This virtio stub is similar to
the lguest one, the memory for the descriptors and the device detection is made
via additional mapped memory on top of the guest storage. We use an external
interrupt with extint code 0x2603 for host->guest notification.
The hypercall definition uses the diag instruction for issuing a hypercall. The
parameters are written in R2-R7, the hypercall number is written in R1. This is
similar to the system call ABI (svc) which can use R1 for the number and R2-R6
for the parameters.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Carsten Otte [Tue, 25 Mar 2008 17:47:44 +0000 (18:47 +0100)]
s390: KVM guest: detect when running on kvm
This patch adds functionality to detect if the kernel runs under the KVM
hypervisor. A macro MACHINE_IS_KVM is exported for device drivers. This
allows drivers to skip device detection if the systems runs non-virtualized.
We also define a preferred console to avoid having the ttyS0, which is a line
mode only console.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch introduces interpretation of some diagnose instruction intercepts.
Diagnose is our classic architected way of doing a hypercall. This patch
features the following diagnose codes:
- vm storage size, that tells the guest about its memory layout
- time slice end, which is used by the guest to indicate that it waits
for a lock and thus cannot use up its time slice in a useful way
- ipl functions, which a guest can use to reset and reboot itself
In order to implement ipl functions, we also introduce an exit reason that
causes userspace to perform various resets on the virtual machine. All resets
are described in the principles of operation book, except KVM_S390_RESET_IPL
which causes a reboot of the machine.
Acked-by: Martin Schwidefsky <martin.schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch introduces in-kernel handling of _some_ sigp interprocessor
signals (similar to ipi).
kvm_s390_handle_sigp() decodes the sigp instruction and calls individual
handlers depending on the operation requested:
- sigp sense tries to retrieve information such as existence or running state
of the remote cpu
- sigp emergency sends an external interrupt to the remove cpu
- sigp stop stops a remove cpu
- sigp stop store status stops a remote cpu, and stores its entire internal
state to the cpus lowcore
- sigp set arch sets the architecture mode of the remote cpu. setting to
ESAME (s390x 64bit) is accepted, setting to ESA/S390 (s390, 31 or 24 bit) is
denied, all others are passed to userland
- sigp set prefix sets the prefix register of a remote cpu
For implementation of this, the stop intercept indication starts to get reused
on purpose: a set of action bits defines what to do once a cpu gets stopped:
ACTION_STOP_ON_STOP really stops the cpu when a stop intercept is recognized
ACTION_STORE_ON_STOP stores the cpu status to lowcore when a stop intercept is
recognized
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch introduces in-kernel handling of some intercepts for privileged
instructions:
handle_set_prefix() sets the prefix register of the local cpu
handle_store_prefix() stores the content of the prefix register to memory
handle_store_cpu_address() stores the cpu number of the current cpu to memory
handle_skey() just decrements the instruction address and retries
handle_stsch() delivers condition code 3 "operation not supported"
handle_chsc() same here
handle_stfl() stores the facility list which contains the
capabilities of the cpu
handle_stidp() stores cpu type/model/revision and such
handle_stsi() stores information about the system topology
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Carsten Otte [Tue, 25 Mar 2008 17:47:26 +0000 (18:47 +0100)]
KVM: s390: interrupt subsystem, cpu timer, waitpsw
This patch contains the s390 interrupt subsystem (similar to in kernel apic)
including timer interrupts (similar to in-kernel-pit) and enabled wait
(similar to in kernel hlt).
In order to achieve that, this patch also introduces intercept handling
for instruction intercepts, and it implements load control instructions.
This patch introduces an ioctl KVM_S390_INTERRUPT which is valid for both
the vm file descriptors and the vcpu file descriptors. In case this ioctl is
issued against a vm file descriptor, the interrupt is considered floating.
Floating interrupts may be delivered to any virtual cpu in the configuration.
The following interrupts are supported:
SIGP STOP - interprocessor signal that stops a remote cpu
SIGP SET PREFIX - interprocessor signal that sets the prefix register of a
(stopped) remote cpu
INT EMERGENCY - interprocessor interrupt, usually used to signal need_reshed
and for smp_call_function() in the guest.
PROGRAM INT - exception during program execution such as page fault, illegal
instruction and friends
RESTART - interprocessor signal that starts a stopped cpu
INT VIRTIO - floating interrupt for virtio signalisation
INT SERVICE - floating interrupt for signalisations from the system
service processor
struct kvm_s390_interrupt, which is submitted as ioctl parameter when injecting
an interrupt, also carrys parameter data for interrupts along with the interrupt
type. Interrupts on s390 usually have a state that represents the current
operation, or identifies which device has caused the interruption on s390.
kvm_s390_handle_wait() does handle waitpsw in two flavors: in case of a
disabled wait (that is, disabled for interrupts), we exit to userspace. In case
of an enabled wait we set up a timer that equals the cpu clock comparator value
and sleep on a wait queue.
[christian: change virtio interrupt to 0x2603]
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
This path introduces handling of sie intercepts in three flavors: Intercepts
are either handled completely in-kernel by kvm_handle_sie_intercept(),
or passed to userspace with corresponding data in struct kvm_run in case
kvm_handle_sie_intercept() returns -ENOTSUPP.
In case of partial execution in kernel with the need of userspace support,
kvm_handle_sie_intercept() may choose to set up struct kvm_run and return
-EREMOTE.
The trivial intercept reasons are handled in this patch:
handle_noop() just does nothing for intercepts that don't require our support
at all
handle_stop() is called when a cpu enters stopped state, and it drops out to
userland after updating our vcpu state
handle_validity() faults in the cpu lowcore if needed, or passes the request
to userland
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Heiko Carstens [Tue, 25 Mar 2008 17:47:20 +0000 (18:47 +0100)]
KVM: s390: arch backend for the kvm kernel module
This patch contains the port of Qumranet's kvm kernel module to IBM zSeries
(aka s390x, mainframe) architecture. It uses the mainframe's virtualization
instruction SIE to run virtual machines with up to 64 virtual CPUs each.
This port is only usable on 64bit host kernels, and can only run 64bit guest
kernels. However, running 31bit applications in guest userspace is possible.
The following source files are introduced by this patch
arch/s390/kvm/kvm-s390.c similar to arch/x86/kvm/x86.c, this implements all
arch callbacks for kvm. __vcpu_run calls back into
sie64a to enter the guest machine context
arch/s390/kvm/sie64a.S assembler function sie64a, which enters guest
context via SIE, and switches world before and after that
include/asm-s390/kvm_host.h contains all vital data structures needed to run
virtual machines on the mainframe
include/asm-s390/kvm.h defines kvm_regs and friends for user access to
guest register content
arch/s390/kvm/gaccess.h functions similar to uaccess to access guest memory
arch/s390/kvm/kvm-s390.h header file for kvm-s390 internals, extended by
later patches
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
s390: KVM preparation: address of the 64bit extint parm in lowcore
The address 0x11b8 is used by z/VM for pfault and diag 250 I/O to
provide a 64 bit extint parameter. virtio uses the same address, so
its time to update the lowcore structure.
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
s390: KVM preparation: host memory management changes for s390 kvm
This patch changes the s390 memory management defintions to use the pgste field
for dirty and reference bit tracking of host and guest code. Usually on s390,
dirty and referenced are tracked in storage keys, which belong to the physical
page. This changes with virtualization: The guest and host dirty/reference bits
are defined to be the logical OR of the values for the mapping and the physical
page. This patch implements the necessary changes in pgtable.h for s390.
There is a common code change in mm/rmap.c, the call to
page_test_and_clear_young must be moved. This is a no-op for all
architecture but s390. page_referenced checks the referenced bits for
the physiscal page and for all mappings:
o The physical page is checked with page_test_and_clear_young.
o The mappings are checked with ptep_test_and_clear_young and friends.
Without pgstes (the current implementation on Linux s390) the physical page
check is implemented but the mapping callbacks are no-ops because dirty
and referenced are not tracked in the s390 page tables. The pgstes introduces
guest and host dirty and reference bits for s390 in the host mapping. These
mapping must be checked before page_test_and_clear_young resets the reference
bit.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Carsten Otte [Tue, 25 Mar 2008 17:47:10 +0000 (18:47 +0100)]
s390: KVM preparation: provide hook to enable pgstes in user pagetable
The SIE instruction on s390 uses the 2nd half of the page table page to
virtualize the storage keys of a guest. This patch offers the s390_enable_sie
function, which reorganizes the page tables of a single-threaded process to
reserve space in the page table:
s390_enable_sie makes sure that the process is single threaded and then uses
dup_mm to create a new mm with reorganized page tables. The old mm is freed
and the process has now a page status extended field after every page table.
Code that wants to exploit pgstes should SELECT CONFIG_PGSTE.
This patch has a small common code hit, namely making dup_mm non-static.
Edit (Carsten): I've modified Martin's patch, following Jeremy Fitzhardinge's
review feedback. Now we do have the prototype for dup_mm in
include/linux/sched.h. Following Martin's suggestion, s390_enable_sie() does now
call task_lock() to prevent race against ptrace modification of mm_users.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Avi Kivity <avi@qumranet.com>
Izik Eidus [Mon, 24 Mar 2008 21:14:53 +0000 (23:14 +0200)]
KVM: x86: hardware task switching support
This emulates the x86 hardware task switch mechanism in software, as it is
unsupported by either vmx or svm. It allows operating systems which use it,
like freedos, to run as kvm guests.
Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Izik Eidus [Thu, 20 Mar 2008 16:17:24 +0000 (18:17 +0200)]
KVM: MMU: fix dirty bit setting when removing write permissions
When mmu_set_spte() checks if a page related to spte should be release as
dirty or clean, it check if the shadow pte was writeble, but in case
rmap_write_protect() is called called it is possible for shadow ptes that were
writeble to become readonly and therefor mmu_set_spte will release the pages
as clean.
This patch fix this issue by marking the page as dirty inside
rmap_write_protect().
Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Avi Kivity [Tue, 18 Mar 2008 09:05:52 +0000 (11:05 +0200)]
KVM: MMU: Set the accessed bit on non-speculative shadow ptes
If we populate a shadow pte due to a fault (and not speculatively due to a
pte write) then we can set the accessed bit on it, as we know it will be
set immediately on the next guest instruction. This saves a read-modify-write
operation.
include/linux/kvm.h defines struct kvm_dirty_log to
[...]
union {
void __user *dirty_bitmap; /* one bit per page */
__u64 padding;
};
__user requires compiler.h to compile. Currently, this works on x86
only coincidentally due to other include files. This patch makes
kvm.h compile in all cases.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Glauber Costa [Mon, 17 Mar 2008 19:08:39 +0000 (16:08 -0300)]
x86: make native_machine_shutdown non-static
it will allow external users to call it. It is mainly
useful for routines that will override its machine_ops
field for its own special purposes, but want to call the
normal shutdown routine after they're done
Signed-off-by: Glauber Costa <gcosta@redhat.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Sheng Yang [Sun, 27 Jan 2008 21:10:22 +0000 (05:10 +0800)]
KVM: In kernel PIT model
The patch moves the PIT model from userspace to kernel, and increases
the timer accuracy greatly.
[marcelo: make last_injected_time per-guest]
Signed-off-by: Sheng Yang <sheng.yang@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Tested-and-Acked-by: Alex Davis <alex14641@yahoo.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Avi Kivity [Tue, 4 Mar 2008 08:44:51 +0000 (10:44 +0200)]
KVM: VMX: Don't adjust tsc offset forward
Most Intel hosts have a stable tsc, and playing with the offset only
reduces accuracy. By limiting tsc offset adjustment only to forward updates,
we effectively disable tsc offset adjustment on these hosts.
projects / linux-2.6-omap-h63xx.git / log