Commit Graph

449 Commits

Author SHA1 Message Date
Stefano Stabellini 016b6f5fe8 xen: Add suspend/resume support for PV on HVM guests.
Suspend/resume requires few different things on HVM: the suspend
hypercall is different; we don't need to save/restore memory related
settings; except the shared info page and the callback mechanism.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-22 16:46:21 -07:00
Sheng Yang 38e20b07ef x86/xen: event channels delivery on HVM.
Set the callback to receive evtchns from Xen, using the
callback vector delivery mechanism.

The traditional way for receiving event channel notifications from Xen
is via the interrupts from the platform PCI device.
The callback vector is a newer alternative that allow us to receive
notifications on any vcpu and doesn't need any PCI support: we allocate
a vector exclusively to receive events, in the vector handler we don't
need to interact with the vlapic, therefore we avoid a VMEXIT.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-22 16:45:59 -07:00
Sheng Yang bee6ab53e6 x86: early PV on HVM features initialization.
Initialize basic pv on hvm features adding a new Xen HVM specific
hypervisor_x86 structure.

Don't try to initialize xen-kbdfront and xen-fbfront when running on HVM
because the backends are not available.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-22 16:45:35 -07:00
Miroslav Rezanina 093d7b4639 xen: release unused free memory
Scan an e820 table and release any memory which lies between e820 entries,
as it won't be used and would just be wasted.  At present this is just to
release any memory beyond the end of the e820 map, but it will also deal
with holes being punched in the map.

Derived from patch by Miroslav Rezanina <mrezanin@redhat.com>

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-20 12:51:22 -07:00
Alex Nixon 7347b4082e xen: Allow unprivileged Xen domains to create iomap pages
PV DomU domains are allowed to map hardware MFNs for PCI passthrough,
but are not generally allowed to map raw machine pages.  In particular,
various pieces of code try to map DMI and ACPI tables in the ISA ROM
range.  We disallow _PAGE_IOMAP for those mappings, so that they are
redirected to a set of local zeroed pages we reserve for that purpose.

[ Impact: prevent passthrough of ISA space, as we only allow PCI ]

Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-06-07 14:33:13 -04:00
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
Ian Campbell 817a824b75 x86, xen: Disable highmem PTE allocation even when CONFIG_HIGHPTE=y
There's a path in the pagefault code where the kernel deliberately
breaks its own locking rules by kmapping a high pte page without
holding the pagetable lock (in at least page_check_address). This
breaks Xen's ability to track the pinned/unpinned state of the
page. There does not appear to be a viable workaround for this
behaviour so simply disable HIGHPTE for all Xen guests.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
LKML-Reference: <1267204562-11844-1-git-send-email-ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Pasi Kärkkäinen <pasik@iki.fi>
Cc: <stable@kernel.org> # .32.x: 14315592: Allow highmem user page tables to be disabled at boot time
Cc: <stable@kernel.org> # .32.x
Cc: <xen-devel@lists.xensource.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-27 14:41:01 -08:00
Ian Campbell e68266b700 x86: xen: 64-bit kernel RPL should be 0
Under Xen 64 bit guests actually run their kernel in ring 3,
however the hypervisor takes care of squashing descriptor the
RPLs transparently (in order to allow them to continue to
differentiate between user and kernel space CS using the RPL).
Therefore the Xen paravirt backend should use RPL==0 instead of
1 (or 3). Using RPL==1 causes generic arch code to take
incorrect code paths because it uses "testl $3, <CS>, je foo"
type tests for a userspace CS and this considers 1==userspace.

This issue was previously masked because get_kernel_rpl() was
omitted when setting CS in kernel_thread(). This was fixed when
kernel_thread() was unified with 32 bit in
f443ff4201.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1263377768-19600-2-git-send-email-ian.campbell@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-01-13 11:23:54 +01:00
Linus Torvalds 11bd04f6f3 Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (109 commits)
  PCI: fix coding style issue in pci_save_state()
  PCI: add pci_request_acs
  PCI: fix BUG_ON triggered by logical PCIe root port removal
  PCI: remove ifdefed pci_cleanup_aer_correct_error_status
  PCI: unconditionally clear AER uncorr status register during cleanup
  x86/PCI: claim SR-IOV BARs in pcibios_allocate_resource
  PCI: portdrv: remove redundant definitions
  PCI: portdrv: remove unnecessary struct pcie_port_data
  PCI: portdrv: minor cleanup for pcie_port_device_register
  PCI: portdrv: add missing irq cleanup
  PCI: portdrv: enable device before irq initialization
  PCI: portdrv: cleanup service irqs initialization
  PCI: portdrv: check capabilities first
  PCI: portdrv: move PME capability check
  PCI: portdrv: remove redundant pcie type calculation
  PCI: portdrv: cleanup pcie_device registration
  PCI: portdrv: remove redundant pcie_port_device_probe
  PCI: Always set prefetchable base/limit upper32 registers
  PCI: read-modify-write the pcie device control register when initiating pcie flr
  PCI: show dma_mask bits in /sys
  ...

Fixed up conflicts in:
	arch/x86/kernel/amd_iommu_init.c
	drivers/pci/dmar.c
	drivers/pci/hotplug/acpiphp_glue.c
2009-12-11 12:18:16 -08:00
Linus Torvalds ab1831b0b8 Merge branch 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen: try harder to balloon up under memory pressure.
  Xen balloon: fix totalram_pages counting.
  xen: explicitly create/destroy stop_machine workqueues outside suspend/resume region.
  xen: improve error handling in do_suspend.
  xen: don't leak IRQs over suspend/resume.
  xen: call clock resume notifier on all CPUs
  xen: use iret for return from 64b kernel to 32b usermode
  xen: don't call dpm_resume_noirq() with interrupts disabled.
  xen: register runstate info for boot CPU early
  xen: register runstate on secondary CPUs
  xen: register timer interrupt with IRQF_TIMER
  xen: correctly restore pfn_to_mfn_list_list after resume
  xen: restore runstate_info even if !have_vcpu_info_placement
  xen: re-register runstate area earlier on resume.
  xen: wait up to 5 minutes for device connetion
  xen: improvement to wait_for_devices()
  xen: fix is_disconnected_device/exists_disconnected_device
  xen/xenbus: make DEVICE_ATTR()s static
2009-12-10 09:35:02 -08:00
Linus Torvalds e33c019722 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (36 commits)
  x86, mm: Correct the implementation of is_untracked_pat_range()
  x86/pat: Trivial: don't create debugfs for memtype if pat is disabled
  x86, mtrr: Fix sorting of mtrr after subtracting
  x86: Move find_smp_config() earlier and avoid bootmem usage
  x86, platform: Change is_untracked_pat_range() to bool; cleanup init
  x86: Change is_ISA_range() into an inline function
  x86, mm: is_untracked_pat_range() takes a normal semiclosed range
  x86, mm: Call is_untracked_pat_range() rather than is_ISA_range()
  x86: UV SGI: Don't track GRU space in PAT
  x86: SGI UV: Fix BAU initialization
  x86, numa: Use near(er) online node instead of roundrobin for NUMA
  x86, numa, bootmem: Only free bootmem on NUMA failure path
  x86: Change crash kernel to reserve via reserve_early()
  x86: Eliminate redundant/contradicting cache line size config options
  x86: When cleaning MTRRs, do not fold WP into UC
  x86: remove "extern" from function prototypes in <asm/proto.h>
  x86, mm: Report state of NX protections during boot
  x86, mm: Clean up and simplify NX enablement
  x86, pageattr: Make set_memory_(x|nx) aware of NX support
  x86, sleep: Always save the value of EFER
  ...

Fix up conflicts (added both iommu_shutdown and is_untracked_pat_range)
to 'struct x86_platform_ops') in
	arch/x86/include/asm/x86_init.h
	arch/x86/kernel/x86_init.c
2009-12-08 13:27:33 -08:00
Chris Wright 5d990b6275 PCI: add pci_request_acs
Commit ae21ee65e8 "PCI: acs p2p upsteram
forwarding enabling" doesn't actually enable ACS.

Add a function to pci core to allow an IOMMU to request that ACS
be enabled.  The existing mechanism of using iommu_found() in the pci
core to know when ACS should be enabled doesn't actually work due to
initialization order;  iommu has only been detected not initialized.

Have Intel and AMD IOMMUs request ACS, and Xen does as well during early
init of dom0.

Cc: Allen Kay <allen.m.kay@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-12-04 16:19:24 -08:00
Jeremy Fitzhardinge 499d19b82b xen: register runstate info for boot CPU early
printk timestamping uses sched_clock, which in turn relies on runstate
info under Xen.  So make sure we set it up before any printks can
be called.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:53 -08:00
Jeremy Fitzhardinge 3905bb2aa7 xen: restore runstate_info even if !have_vcpu_info_placement
Even if have_vcpu_info_placement is not set, we still need to set up
the runstate area on each resumed vcpu.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:51 -08:00
Ian Campbell be012920ec xen: re-register runstate area earlier on resume.
This is necessary to ensure the runstate area is available to
xen_sched_clock before any calls to printk which will require it in
order to provide a timestamp.

I chose to pull the xen_setup_runstate_info out of xen_time_init into
the caller in order to maintain parity with calling
xen_setup_runstate_info separately from calling xen_time_resume.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-12-03 11:14:50 -08:00
H. Peter Anvin 4763ed4d45 x86, mm: Clean up and simplify NX enablement
The 32- and 64-bit code used very different mechanisms for enabling
NX, but even the 32-bit code was enabling NX in head_32.S if it is
available.  Furthermore, we had a bewildering collection of tests for
the available of NX.

This patch:

a) merges the 32-bit set_nx() and the 64-bit check_efer() function
   into a single x86_configure_nx() function.  EFER control is left
   to the head code.

b) eliminates the nx_enabled variable entirely.  Things that need to
   test for NX enablement can verify __supported_pte_mask directly,
   and cpu_has_nx gives the supported status of NX.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Chris Wright <chrisw@sous-sol.org>
LKML-Reference: <1258154897-6770-5-git-send-email-hpa@zytor.com>
Acked-by: Kees Cook <kees.cook@canonical.com>
2009-11-16 13:44:59 -08:00
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
Jeremy Fitzhardinge 82d6469916 xen: mask extended topology info in cpuid
A Xen guest never needs to know about extended topology, and knowing
would just confuse it.

This patch just zeros ebx in leaf 0xb which indicates no topology info,
preventing a crash under Xen on cpus which support this leaf.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-11-03 11:09:12 -08:00
Jeremy Fitzhardinge 973df35ed9 xen: set up mmu_ops before trying to set any ptes
xen_setup_stackprotector() ends up trying to set page protections,
so we need to have vm_mmu_ops set up before trying to do so.
Failing to do so causes an early boot crash.

[ Impact: Fix early crash under Xen. ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-10-27 16:54:19 -07:00
Ingo Molnar 14c93e8eba Merge branch 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen into x86/urgent 2009-09-23 14:35:10 +02:00
Jeremy Fitzhardinge b75fe4e5b8 xen: check EFER for NX before setting up GDT mapping
x86-64 assumes NX is available by default, so we need to
explicitly check for it before using NX.  Some first-generation
Intel x86-64 processors didn't support NX, and even recent systems
allow it to be disabled in BIOS.

[ Impact: prevent Xen crash on NX-less 64-bit machines ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2009-09-21 13:49:43 -07:00
Linus Torvalds 78f28b7c55 Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (38 commits)
  x86: Move get/set_wallclock to x86_platform_ops
  x86: platform: Fix section annotations
  x86: apic namespace cleanup
  x86: Distangle ioapic and i8259
  x86: Add Moorestown early detection
  x86: Add hardware_subarch ID for Moorestown
  x86: Add early platform detection
  x86: Move tsc_init to late_time_init
  x86: Move tsc_calibration to x86_init_ops
  x86: Replace the now identical time_32/64.c by time.c
  x86: time_32/64.c unify profile_pc
  x86: Move calibrate_cpu to tsc.c
  x86: Make timer setup and global variables the same in time_32/64.c
  x86: Remove mca bus ifdef from timer interrupt
  x86: Simplify timer_ack magic in time_32.c
  x86: Prepare unification of time_32/64.c
  x86: Remove do_timer hook
  x86: Add timer_init to x86_init_ops
  x86: Move percpu clockevents setup to x86_init_ops
  x86: Move xen_post_allocator_init into xen_pagetable_setup_done
  ...

Fix up conflicts in arch/x86/include/asm/io_apic.h
2009-09-18 14:05:47 -07:00
Feng Tang 7bd867dfb4 x86: Move get/set_wallclock to x86_platform_ops
get/set_wallclock() have already a set of platform dependent
implementations (default, EFI, paravirt). MRST will add another
variant.

Moving them to platform ops simplifies the existing code and minimizes
the effort to integrate new variants.

Signed-off-by: Feng Tang <feng.tang@intel.com>
LKML-Reference: <new-submission>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-09-16 14:34:50 +02:00
Linus Torvalds b8cb48aae1 Merge branch 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-xen-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: split __phys_addr out into separate file
  xen: use stronger barrier after unlocking lock
  xen: only enable interrupts while actually blocking for spinlock
  xen: make -fstack-protector work under Xen
2009-09-14 10:23:49 -07:00
Linus Torvalds c7208de304 Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (22 commits)
  x86: Fix code patching for paravirt-alternatives on 486
  x86, msr: change msr-reg.o to obj-y, and export its symbols
  x86: Use hard_smp_processor_id() to get apic id for AMD K8 cpus
  x86, sched: Workaround broken sched domain creation for AMD Magny-Cours
  x86, mcheck: Use correct cpumask for shared bank4
  x86, cacheinfo: Fixup L3 cache information for AMD multi-node processors
  x86: Fix CPU llc_shared_map information for AMD Magny-Cours
  x86, msr: Fix msr-reg.S compilation with gas 2.16.1, on 32-bit too
  x86: Move kernel_fpu_using to irq_fpu_usable in asm/i387.h
  x86, msr: fix msr-reg.S compilation with gas 2.16.1
  x86, msr: Export the register-setting MSR functions via /dev/*/msr
  x86, msr: Create _on_cpu helpers for {rw,wr}msr_safe_regs()
  x86, msr: Have the _safe MSR functions return -EIO, not -EFAULT
  x86, msr: CFI annotations, cleanups for msr-reg.S
  x86, asm: Make _ASM_EXTABLE() usable from assembly code
  x86, asm: Add 32-bit versions of the combined CFI macros
  x86, AMD: Disable wrongly set X86_FEATURE_LAHF_LM CPUID bit
  x86, msr: Rewrite AMD rd/wrmsr variants
  x86, msr: Add rd/wrmsr interfaces with preset registers
  x86: add specific support for Intel Atom architecture
  ...
2009-09-14 07:57:32 -07:00
Jeremy Fitzhardinge 577eebeae3 xen: make -fstack-protector work under Xen
-fstack-protector uses a special per-cpu "stack canary" value.
gcc generates special code in each function to test the canary to make
sure that the function's stack hasn't been overrun.

On x86-64, this is simply an offset of %gs, which is the usual per-cpu
base segment register, so setting it up simply requires loading %gs's
base as normal.

On i386, the stack protector segment is %gs (rather than the usual kernel
percpu %fs segment register).  This requires setting up the full kernel
GDT and then loading %gs accordingly.  We also need to make sure %gs is
initialized when bringing up secondary cpus too.

To keep things consistent, we do the full GDT/segment register setup on
both architectures.

Because we need to avoid -fstack-protected code before setting up the GDT
and because there's no way to disable it on a per-function basis, several
files need to have stack-protector inhibited.

[ Impact: allow Xen booting with stack-protector enabled ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-09-09 16:37:39 -07:00
H. Peter Anvin 0cc0213e73 x86, msr: Have the _safe MSR functions return -EIO, not -EFAULT
For some reason, the _safe MSR functions returned -EFAULT, not -EIO.
However, the only user which cares about the return code as anything
other than a boolean is the MSR driver, which wants -EIO.  Change it
to -EIO across the board.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
2009-08-31 15:15:23 -07:00
Thomas Gleixner 2d826404f0 x86: Move tsc_calibration to x86_init_ops
TSC calibration is modified by the vmware hypervisor and paravirt by
separate means. Moorestown wants to add its own calibration routine as
well. So make calibrate_tsc a proper x86_init_ops function and
override it by paravirt or by the early setup of the vmware
hypervisor.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:47 +02:00
Thomas Gleixner 845b3944bb x86: Add timer_init to x86_init_ops
The timer init code is convoluted with several quirks and the paravirt
timer chooser. Figuring out which code path is actually taken is not
for the faint hearted.

Move the numaq TSC quirk to tsc_pre_init x86_init_ops function and
replace the paravirt time chooser and the remaining x86 quirk with a
simple x86_init_ops function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner 736decac64 x86: Move percpu clockevents setup to x86_init_ops
paravirt overrides the setup of the default apic timers as per cpu
timers. Moorestown needs to override that as well.

Move it to x86_init_ops setup and create a separate x86_cpuinit struct
which holds the function for the secondary evtl. hotplugabble CPUs.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:46 +02:00
Thomas Gleixner f1d7062a23 x86: Move xen_post_allocator_init into xen_pagetable_setup_done
We really do not need two paravirt/x86_init_ops functions which are
called in two consecutive source lines. Move the only user of
post_allocator_init into the already existing pagetable_setup_done
function.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 030cb6c00d x86: Move paravirt pagetable_setup to x86_init_ops
Replace more paravirt hackery by proper x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 6f30c1ac3f x86: Move paravirt banner printout to x86_init_ops
Replace another obscure paravirt magic and move it to
x86_init_ops. Such a hook is also useful for embedded and special
hardware.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 42bbdb43b1 x86: Replace ARCH_SETUP by a proper x86_init_ops
ARCH_SETUP is a horrible leftover from the old arch/i386 mach support
code. It still has a lonely user in xen. Move it to x86_init_ops.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-31 09:35:45 +02:00
Thomas Gleixner 6b18ae3e2f x86: Move memory_setup to x86_init_ops
memory_setup is overridden by x86_quirks and by paravirts with weak
functions and quirks. Unify the whole mess and make it an
unconditional x86_init_ops function which defaults to the standard
function and can be overridden by the early platform code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-27 17:12:52 +02:00
H. Peter Anvin 7adb4df410 x86, xen: Initialize cx to suppress warning
Initialize cx before calling xen_cpuid(), in order to suppress the
"may be used uninitialized in this function" warning.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2009-08-25 21:10:32 -07:00
Jeremy Fitzhardinge d560bc6157 x86, xen: Suppress WP test on Xen
Xen always runs on CPUs which properly support WP enforcement in
privileged mode, so there's no need to test for it.

This also works around a crash reported by Arnd Hannemann, though I
think its just a band-aid for that case.

Reported-by: Arnd Hannemann <hannemann@nets.rwth-aachen.de>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-25 21:10:32 -07:00
Ingo Molnar cbcb340cb6 Merge branch 'bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen into x86/urgent 2009-08-20 12:05:24 +02:00
Jeremy Fitzhardinge ce2eef33d3 xen: rearrange things to fix stackprotector
Make sure the stack-protector segment registers are properly set up
before calling any functions which may have stack-protection compiled
into them.

[ Impact: prevent Xen early-boot crash when stack-protector is enabled ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-08-19 17:09:28 -07:00
Jeremy Fitzhardinge a789ed5fb6 xen: cache cr0 value to avoid trap'n'emulate for read_cr0
stts() is implemented in terms of read_cr0/write_cr0 to update the
state of the TS bit.  This happens during context switch, and so
is fairly performance critical.  Rather than falling back to
a trap-and-emulate native read_cr0, implement our own by caching
the last-written value from write_cr0 (the TS bit is the only one
we really care about).

Impact: optimise Xen context switches
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-05-08 15:55:24 -07:00
Jeremy Fitzhardinge b80119bb35 xen/x86-64: clean up warnings about IST-using traps
Ignore known IST-using traps.  Aside from the debugger traps, they're
low-level faults which Xen will handle for us, so the kernel needn't
worry about them.  Keep warning in case unknown trap starts using IST.

Impact: suppress spurious warnings
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-05-08 15:55:10 -07:00
Jeremy Fitzhardinge 6cac5a9246 xen/x86-64: fix breakpoints and hardware watchpoints
Native x86-64 uses the IST mechanism to run int3 and debug traps on
an alternative stack.  Xen does not do this, and so the frames were
being misinterpreted by the ptrace code.  This change special-cases
these two exceptions by using Xen variants which run on the normal
kernel stack properly.

Impact: avoid crash or bad data when IST trap is invoked under Xen
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-05-08 15:51:03 -07:00
Jeremy Fitzhardinge 2b2a733447 xen: clean up gate trap/interrupt constants
Use GATE_INTERRUPT/TRAP rather than 0xe/f.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-04-08 14:25:50 -07:00
Jeremy Fitzhardinge bc6081ff98 xen: set _PAGE_NX in __supported_pte_mask before pagetable construction
Some 64-bit machines don't support the NX flag in ptes.
Check for NX before constructing the kernel pagetables.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-04-08 14:25:49 -07:00
Jeremy Fitzhardinge 191216b928 xen: mask XSAVE from cpuid
Xen leaves XSAVE set in cpuid, but doesn't allow cr4.OSXSAVE
to be set.  This confuses the kernel and it ends up crashing on
an xsetbv instruction.

At boot time, try to set cr4.OSXSAVE, and mask XSAVE out of
cpuid it we can't.  This will produce a spurious error from Xen,
but allows us to support XSAVE if/when Xen does.

This also factors out the cpuid mask decisions to boot time.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-04-08 11:51:46 -07:00
Jeremy Fitzhardinge c667d5d6a7 xen: remove xen_load_gdt debug
Don't need the noise.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-04-08 11:51:45 -07:00
Jeremy Fitzhardinge a957fac500 xen: make xen_load_gdt simpler
Remove use of multicall machinery which is unused (gdt loading
is never performance critical).  This removes the implicit use
of percpu variables, which simplifies understanding how
the percpu code's use of load_gdt interacts with this code.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-04-08 11:51:45 -07:00
Jeremy Fitzhardinge c7da8c829b xen: clean up xen_load_gdt
Makes the logic a bit clearer.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-04-08 11:51:45 -07:00
Jeremy Fitzhardinge 6d02c42698 xen: clean up gate trap/interrupt constants
Use GATE_INTERRUPT/TRAP rather than 0xe/f.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-30 09:25:36 -07:00
Jeremy Fitzhardinge 707ebbc81c xen: set _PAGE_NX in __supported_pte_mask before pagetable construction
Some 64-bit machines don't support the NX flag in ptes.
Check for NX before constructing the kernel pagetables.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-30 09:25:36 -07:00
Jeremy Fitzhardinge e826fe1ba1 xen: mask XSAVE from cpuid
Xen leaves XSAVE set in cpuid, but doesn't allow cr4.OSXSAVE
to be set.  This confuses the kernel and it ends up crashing on
an xsetbv instruction.

At boot time, try to set cr4.OSXSAVE, and mask XSAVE out of
cpuid it we can't.  This will produce a spurious error from Xen,
but allows us to support XSAVE if/when Xen does.

This also factors out the cpuid mask decisions to boot time.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-30 09:25:28 -07:00
Jeremy Fitzhardinge b4b7e58590 xen: remove xen_load_gdt debug
Don't need the noise.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-30 09:25:26 -07:00
Jeremy Fitzhardinge 3ce5fa7ebf xen: make xen_load_gdt simpler
Remove use of multicall machinery which is unused (gdt loading
is never performance critical).  This removes the implicit use
of percpu variables, which simplifies understanding how
the percpu code's use of load_gdt interacts with this code.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-30 09:25:25 -07:00
Jeremy Fitzhardinge 6ed6bf428a xen: clean up xen_load_gdt
Makes the logic a bit clearer.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2009-03-30 09:25:24 -07:00
Jeremy Fitzhardinge 224101ed69 x86/paravirt: finish change from lazy cpu to context switch start/end
Impact: fix lazy context switch API

Pass the previous and next tasks into the context switch start
end calls, so that the called functions can properly access the
task state (esp in end_context_switch, in which the next task
is not yet completely current).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:36:01 -07:00
Jeremy Fitzhardinge b407fc57b8 x86/paravirt: flush pending mmu updates on context switch
Impact: allow preemption during lazy mmu updates

If we're in lazy mmu mode when context switching, leave
lazy mmu mode, but remember the task's state in
TIF_LAZY_MMU_UPDATES.  When we resume the task, check this
flag and re-enter lazy mmu mode if its set.

This sets things up for allowing lazy mmu mode while preemptible,
though that won't actually be active until the next change.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2009-03-29 23:36:00 -07:00
Ingo Molnar 91d75e209b Merge branch 'x86/core' into core/percpu 2009-03-04 02:29:19 +01:00
Jeremy Fitzhardinge 9976b39b50 xen: deal with virtually mapped percpu data
The virtually mapped percpu space causes us two problems:

 - for hypercalls which take an mfn, we need to do a full pagetable
   walk to convert the percpu va into an mfn, and

 - when a hypercall requires a page to be mapped RO via all its aliases,
   we need to make sure its RO in both the percpu mapping and in the
   linear mapping

This primarily affects the gdt and the vcpu info structure.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-02 12:58:19 +01:00
Ingo Molnar 13b2eda64d Merge branch 'x86/urgent' into x86/core
Conflicts:
	arch/x86/mach-voyager/voyager_smp.c
2009-02-26 06:30:42 +01:00
Jeremy Fitzhardinge 55d8085671 xen: disable interrupts early, as start_kernel expects
This avoids a lockdep warning from:
	if (DEBUG_LOCKS_WARN_ON(unlikely(!early_boot_irqs_enabled)))
		return;
in trace_hardirqs_on_caller();

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 18:51:57 +01:00
Ingo Molnar 7b6aa335ca x86, apic: remove genapic.h
Impact: cleanup

Remove genapic.h and remove all references to it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-17 17:52:44 +01:00
Yinghai Lu c1eeb2de41 x86: fold apic_ops into genapic
Impact: cleanup

make it simpler, don't need have one extra struct.

v2: fix the sgi_uv build

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-17 12:22:20 +01:00
Tejun Heo ccbeed3a05 x86: make lazy %gs optional on x86_32
Impact: pt_regs changed, lazy gs handling made optional, add slight
        overhead to SAVE_ALL, simplifies error_code path a bit

On x86_32, %gs hasn't been used by kernel and handled lazily.  pt_regs
doesn't have place for it and gs is saved/loaded only when necessary.
In preparation for stack protector support, this patch makes lazy %gs
handling optional by doing the followings.

* Add CONFIG_X86_32_LAZY_GS and place for gs in pt_regs.

* Save and restore %gs along with other registers in entry_32.S unless
  LAZY_GS.  Note that this unfortunately adds "pushl $0" on SAVE_ALL
  even when LAZY_GS.  However, it adds no overhead to common exit path
  and simplifies entry path with error code.

* Define different user_gs accessors depending on LAZY_GS and add
  lazy_save_gs() and lazy_load_gs() which are noop if !LAZY_GS.  The
  lazy_*_gs() ops are used to save, load and clear %gs lazily.

* Define ELF_CORE_COPY_KERNEL_REGS() which always read %gs directly.

xen and lguest changes need to be verified.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-10 00:42:00 +01:00
Jeremy Fitzhardinge e4d0407185 xen: use direct ops on 64-bit
Enable the use of the direct vcpu-access operations on 64-bit.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-04 17:00:50 -08:00
Jeremy Fitzhardinge 383414322b xen: setup percpu data pointers
We need to access percpu data fairly early, so set up the percpu
registers as soon as possible.  We only need to load the appropriate
segment register.  We already have a GDT, but its hard to change it
early because we need to manipulate the pagetable to do so, and that
hasn't been set up yet.

Also, set the kernel stack when bringing up secondary CPUs.  If we
don't they all end up sharing the same stack...

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2009-02-04 16:59:02 -08:00
H. Peter Anvin 327641da8e Merge branch 'core/percpu' into x86/paravirt 2009-02-04 16:58:26 -08:00
Jeremy Fitzhardinge 795f99b61d xen: setup percpu data pointers
Impact: fix xen booting

We need to access percpu data fairly early, so set up the percpu
registers as soon as possible.  We only need to load the appropriate
segment register.  We already have a GDT, but its hard to change it
early because we need to manipulate the pagetable to do so, and that
hasn't been set up yet.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-31 14:28:58 +09:00
Jeremy Fitzhardinge ecb93d1ccd x86/paravirt: add register-saving thunks to reduce caller register pressure
Impact: Optimization

One of the problems with inserting a pile of C calls where previously
there were none is that the register pressure is greatly increased.
The C calling convention says that the caller must expect a certain
set of registers may be trashed by the callee, and that the callee can
use those registers without restriction.  This includes the function
argument registers, and several others.

This patch seeks to alleviate this pressure by introducing wrapper
thunks that will do the register saving/restoring, so that the
callsite doesn't need to worry about it, but the callee function can
be conventional compiler-generated code.  In many cases (particularly
performance-sensitive cases) the callee will be in assembler anyway,
and need not use the compiler's calling convention.

Standard calling convention is:
	 arguments	    return	scratch
x86-32	 eax edx ecx	    eax		?
x86-64	 rdi rsi rdx rcx    rax		r8 r9 r10 r11

The thunk preserves all argument and scratch registers.  The return
register is not preserved, and is available as a scratch register for
unwrapped callee code (and of course the return value).

Wrapped function pointers are themselves wrapped in a struct
paravirt_callee_save structure, in order to get some warning from the
compiler when functions with mismatched calling conventions are used.

The most common paravirt ops, both statically and dynamically, are
interrupt enable/disable/save/restore, so handle them first.  This is
particularly easy since their calls are handled specially anyway.

XXX Deal with VMI.  What's their calling convention?

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-30 14:51:45 -08:00
Jeremy Fitzhardinge 319f3ba52c xen: move remaining mmu-related stuff into mmu.c
Impact: Cleanup

Move remaining mmu-related stuff into mmu.c.
A general cleanup, and lay the groundwork for later patches.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-01-30 14:51:14 -08:00
H. Peter Anvin 9b7ed8faa0 Merge branch 'core/percpu' into x86/paravirt 2009-01-30 14:50:57 -08:00
Jeremy Fitzhardinge ab897d2013 x86/pvops: remove pte_flags pvop
pte_flags() was introduced as a new pvop in order to extract just the
flags portion of a pte, which is a potentially cheaper operation than
extracting the page number as well.  It turns out this operation is
not needed, because simply using a mask to extract the flags from a
pte is sufficient for all current users.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-22 23:35:20 +01:00
Brian Gerst 8ce031972b x86: remove pda_init()
Impact: cleanup

Copy the code to cpu_init() to satisfy the requirement that the cpu
be reinitialized.  Remove all other calls, since the segments are
already initialized in head_64.S.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-20 12:29:19 +09:00
Ingo Molnar 6dbde35308 percpu: add optimized generic percpu accessors
It is an optimization and a cleanup, and adds the following new
generic percpu methods:

  percpu_read()
  percpu_write()
  percpu_add()
  percpu_sub()
  percpu_and()
  percpu_or()
  percpu_xor()

and implements support for them on x86. (other architectures will fall
back to a default implementation)

The advantage is that for example to read a local percpu variable,
instead of this sequence:

 return __get_cpu_var(var);

 ffffffff8102ca2b:	48 8b 14 fd 80 09 74 	mov    -0x7e8bf680(,%rdi,8),%rdx
 ffffffff8102ca32:	81
 ffffffff8102ca33:	48 c7 c0 d8 59 00 00 	mov    $0x59d8,%rax
 ffffffff8102ca3a:	48 8b 04 10          	mov    (%rax,%rdx,1),%rax

We can get a single instruction by using the optimized variants:

 return percpu_read(var);

 ffffffff8102ca3f:	65 48 8b 05 91 8f fd 	mov    %gs:0x7efd8f91(%rip),%rax

I also cleaned up the x86-specific APIs and made the x86 code use
these new generic percpu primitives.

tj: * fixed generic percpu_sub() definition as Roel Kluin pointed out
    * added percpu_and() for completeness's sake
    * made generic percpu ops atomic against preemption

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Tejun Heo <tj@kernel.org>
2009-01-16 14:20:31 +01:00
Tejun Heo 004aa322f8 x86: misc clean up after the percpu update
Do the following cleanups:

* kill x86_64_init_pda() which now is equivalent to pda_init()

* use per_cpu_offset() instead of cpu_pda() when initializing
  initial_gs

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-16 14:20:26 +01:00
Rusty Russell 4595f9620c x86: change flush_tlb_others to take a const struct cpumask
Impact: reduce stack usage, use new cpumask API.

This is made a little more tricky by uv_flush_tlb_others which
actually alters its argument, for an IPI to be sent to the remaining
cpus in the mask.

I solve this by allocating a cpumask_var_t for this case and falling back
to IPI should this fail.

To eliminate temporaries in the caller, all flush_tlb_others implementations
now do the this-cpu-elimination step themselves.

Note also the curious "cpus_or(f->flush_cpumask, cpumask, f->flush_cpumask)"
which has been there since pre-git and yet f->flush_cpumask is always zero
at this point.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
2009-01-11 19:13:06 +01:00
Jeremy Fitzhardinge ecbf29cdb3 xen: clean up asm/xen/hypervisor.h
Impact: cleanup

hypervisor.h had accumulated a lot of crud, including lots of spurious
#includes.  Clean it all up, and go around fixing up everything else
accordingly.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 21:50:31 +01:00
Tej f63c2f2489 xen: whitespace/checkpatch cleanup
Impact: cleanup

Signed-off-by: Tej <bewith.tej@gmail.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-16 21:05:01 +01:00
Jeremy Fitzhardinge d05fdf3160 xen: make sure stray alias mappings are gone before pinning
Xen requires that all mappings of pagetable pages are read-only, so
that they can't be updated illegally.  As a result, if a page is being
turned into a pagetable page, we need to make sure all its mappings
are RO.

If the page had been used for ioremap or vmalloc, it may still have
left over mappings as a result of not having been lazily unmapped.
This change makes sure we explicitly mop them all up before pinning
the page.

Unlike aliases created by kmap, the there can be vmalloc aliases even
for non-high pages, so we must do the flush unconditionally.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Linux Memory Management List <linux-mm@kvack.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-07 10:05:59 +01:00
Nick Piggin db64fe0225 mm: rewrite vmap layer
Rewrite the vmap allocator to use rbtrees and lazy tlb flushing, and
provide a fast, scalable percpu frontend for small vmaps (requires a
slightly different API, though).

The biggest problem with vmap is actually vunmap.  Presently this requires
a global kernel TLB flush, which on most architectures is a broadcast IPI
to all CPUs to flush the cache.  This is all done under a global lock.  As
the number of CPUs increases, so will the number of vunmaps a scaled
workload will want to perform, and so will the cost of a global TLB flush.
 This gives terrible quadratic scalability characteristics.

Another problem is that the entire vmap subsystem works under a single
lock.  It is a rwlock, but it is actually taken for write in all the fast
paths, and the read locking would likely never be run concurrently anyway,
so it's just pointless.

This is a rewrite of vmap subsystem to solve those problems.  The existing
vmalloc API is implemented on top of the rewritten subsystem.

The TLB flushing problem is solved by using lazy TLB unmapping.  vmap
addresses do not have to be flushed immediately when they are vunmapped,
because the kernel will not reuse them again (would be a use-after-free)
until they are reallocated.  So the addresses aren't allocated again until
a subsequent TLB flush.  A single TLB flush then can flush multiple
vunmaps from each CPU.

XEN and PAT and such do not like deferred TLB flushing because they can't
always handle multiple aliasing virtual addresses to a physical address.
They now call vm_unmap_aliases() in order to flush any deferred mappings.
That call is very expensive (well, actually not a lot more expensive than
a single vunmap under the old scheme), however it should be OK if not
called too often.

The virtual memory extent information is stored in an rbtree rather than a
linked list to improve the algorithmic scalability.

There is a per-CPU allocator for small vmaps, which amortizes or avoids
global locking.

To use the per-CPU interface, the vm_map_ram / vm_unmap_ram interfaces
must be used in place of vmap and vunmap.  Vmalloc does not use these
interfaces at the moment, so it will not be quite so scalable (although it
will use lazy TLB flushing).

As a quick test of performance, I ran a test that loops in the kernel,
linearly mapping then touching then unmapping 4 pages.  Different numbers
of tests were run in parallel on an 4 core, 2 socket opteron.  Results are
in nanoseconds per map+touch+unmap.

threads           vanilla         vmap rewrite
1                 14700           2900
2                 33600           3000
4                 49500           2800
8                 70631           2900

So with a 8 cores, the rewritten version is already 25x faster.

In a slightly more realistic test (although with an older and less
scalable version of the patch), I ripped the not-very-good vunmap batching
code out of XFS, and implemented the large buffer mapping with vm_map_ram
and vm_unmap_ram...  along with a couple of other tricks, I was able to
speed up a large directory workload by 20x on a 64 CPU system.  I believe
vmap/vunmap is actually sped up a lot more than 20x on such a system, but
I'm running into other locks now.  vmap is pretty well blown off the
profiles.

Before:
1352059 total                                      0.1401
798784 _write_lock                              8320.6667 <- vmlist_lock
529313 default_idle                             1181.5022
 15242 smp_call_function                         15.8771  <- vmap tlb flushing
  2472 __get_vm_area_node                         1.9312  <- vmap
  1762 remove_vm_area                             4.5885  <- vunmap
   316 map_vm_area                                0.2297  <- vmap
   312 kfree                                      0.1950
   300 _spin_lock                                 3.1250
   252 sn_send_IPI_phys                           0.4375  <- tlb flushing
   238 vmap                                       0.8264  <- vmap
   216 find_lock_page                             0.5192
   196 find_next_bit                              0.3603
   136 sn2_send_IPI                               0.2024
   130 pio_phys_write_mmr                         2.0312
   118 unmap_kernel_range                         0.1229

After:
 78406 total                                      0.0081
 40053 default_idle                              89.4040
 33576 ia64_spinlock_contention                 349.7500
  1650 _spin_lock                                17.1875
   319 __reg_op                                   0.5538
   281 _atomic_dec_and_lock                       1.0977
   153 mutex_unlock                               1.5938
   123 iget_locked                                0.1671
   117 xfs_dir_lookup                             0.1662
   117 dput                                       0.1406
   114 xfs_iget_core                              0.0268
    92 xfs_da_hashname                            0.1917
    75 d_alloc                                    0.0670
    68 vmap_page_range                            0.0462 <- vmap
    58 kmem_cache_alloc                           0.0604
    57 memset                                     0.0540
    52 rb_next                                    0.1625
    50 __copy_user                                0.0208
    49 bitmap_find_free_region                    0.2188 <- vmap
    46 ia64_sn_udelay                             0.1106
    45 find_inode_fast                            0.1406
    42 memcmp                                     0.2188
    42 finish_task_switch                         0.1094
    42 __d_lookup                                 0.0410
    40 radix_tree_lookup_slot                     0.1250
    37 _spin_unlock_irqrestore                    0.3854
    36 xfs_bmapi                                  0.0050
    36 kmem_cache_free                            0.0256
    35 xfs_vn_getattr                             0.0322
    34 radix_tree_lookup                          0.1062
    33 __link_path_walk                           0.0035
    31 xfs_da_do_buf                              0.0091
    30 _xfs_buf_find                              0.0204
    28 find_get_page                              0.0875
    27 xfs_iread                                  0.0241
    27 __strncpy_from_user                        0.2812
    26 _xfs_buf_initialize                        0.0406
    24 _xfs_buf_lookup_pages                      0.0179
    24 vunmap_page_range                          0.0250 <- vunmap
    23 find_lock_page                             0.0799
    22 vm_map_ram                                 0.0087 <- vmap
    20 kfree                                      0.0125
    19 put_page                                   0.0330
    18 __kmalloc                                  0.0176
    17 xfs_da_node_lookup_int                     0.0086
    17 _read_lock                                 0.0885
    17 page_waitqueue                             0.0664

vmap has gone from being the top 5 on the profiles and flushing the crap
out of all TLBs, to using less than 1% of kernel time.

[akpm@linux-foundation.org: cleanups, section fix]
[akpm@linux-foundation.org: fix build on alpha]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:32 -07:00
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
Ingo Molnar d84705969f Merge branch 'x86/apic' into x86-v28-for-linus-phase4-B
Conflicts:
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/apic_64.c
	arch/x86/kernel/setup.c
	drivers/pci/intel-iommu.c
	include/asm-x86/cpufeature.h
	include/asm-x86/dma-mapping.h
2008-10-11 20:17:36 +02:00
Ian Campbell 5dc64a3442 xen: do not reserve 2 pages of padding between hypervisor and fixmap.
When reserving space for the hypervisor the Xen paravirt backend adds
an extra two pages (this was carried forward from the 2.6.18-xen tree
which had them "for safety"). Depending on various CONFIG options this
can cause the boot time fixmaps to span multiple PMDs which is not
supported and triggers a WARN in early_ioremap_init().

This was exposed by 2216d199b1 which
moved the dmi table parsing earlier.
    x86: fix CONFIG_X86_RESERVE_LOW_64K=y

    The bad_bios_dmi_table() quirk never triggered because we do DMI setup
    too late. Move it a bit earlier.

There is no real reason to reserve these two extra pages and the
fixmap already incorporates FIX_HOLE which serves the same
purpose. None of the other callers of reserve_top_address do this.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-10 13:00:15 +02:00
Ingo Molnar e496e3d645 Merge branches 'x86/alternatives', 'x86/cleanups', 'x86/commandline', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/doc', 'x86/exports', 'x86/fpu', 'x86/gart', 'x86/idle', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/oprofile', 'x86/paravirt', 'x86/reboot', 'x86/sparse-fixes', 'x86/tsc', 'x86/urgent' and 'x86/vmalloc' into x86-v28-for-linus-phase1 2008-10-06 18:17:07 +02:00
Jeremy Fitzhardinge db053b86f4 xen: clean up x86-64 warnings
There are a couple of Xen features which rely on directly accessing
per-cpu data via a segment register, which is not yet available on
x86-64.  In the meantime, just disable direct access to the vcpu info
structure; this leaves some of the code as dead, but it will come to
life in time, and the warnings are suppressed.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-03 10:04:10 +02:00
Jeremy Fitzhardinge 6a9e91846b xen: fix pinning when not using split pte locks
We only pin PTE pages when using split PTE locks, so don't do the
pin/unpin when attaching/detaching pte pages to a pinned pagetable.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-10 14:05:53 +02:00
Eduardo Habkost e4a6be4d28 x86, xen: Use native_pte_flags instead of native_pte_val for .pte_flags
Using native_pte_val triggers the BUG_ON() in the paravirt_ops
version of pte_flags().

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-06 20:13:58 +02:00
Eduardo Habkost f86399396c x86, paravirt_ops: use unsigned long instead of u32 for alloc_p*() pfn args
This patch changes the pfn args from 'u32' to 'unsigned long'
on alloc_p*() functions on paravirt_ops, and the corresponding
implementations for Xen and VMI. The prototypes for CONFIG_PARAVIRT=n
are already using unsigned long, so paravirt.h now matches the prototypes
on asm-x86/pgalloc.h.

It shouldn't result in any changes on generated code on 32-bit, with
or without CONFIG_PARAVIRT. On both cases, 'codiff -f' didn't show any
change after applying this patch.

On 64-bit, there are (expected) binary changes only when CONFIG_PARAVIRT
is enabled, as the patch is really supposed to change the size of the
pfn args.

[ v2: KVM_GUEST: use the right parameter type on kvm_release_pt() ]

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Acked-by: Zachary Amsden <zach@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-22 05:34:44 +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
Eduardo Habkost 169ad16bb8 xen_alloc_ptpage: cast PFN_PHYS() argument to unsigned long
Currently paravirt_ops alloc_p*() uses u32 for the pfn args. We should
change that later, but while the pfn parameter is still u32, we need to
cast the PFN_PHYS() argument at xen_alloc_ptpage() to unsigned long,
otherwise it will lose bits on the shift.

I think PFN_PHYS() should behave better when fed with smaller integers,
but a cast to unsigned long won't be enough for all cases on 32-bit PAE,
and a cast to u64 would be overkill for most users of PFN_PHYS().

We could have two different flavors of PFN_PHYS: one for low pages
only (unsigned long) and another that works for any page (u64)),
but while we don't have it, we will need the cast to unsigned long on
xen_alloc_ptpage().

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-31 17:10:35 +02:00
Jeremy Fitzhardinge cef43bf6b3 xen: fix allocation and use of large ldts, cleanup
Add a proper comment for set_aliased_prot() and fix an
unsigned long/void * warning.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-31 17:10:35 +02:00
Jeremy Fitzhardinge 0d1edf46ba xen: compile irq functions without -pg for ftrace
For some reason I managed to miss a bunch of irq-related functions
which also need to be compiled without -pg when using ftrace.  This
patch moves them into their own file, and starts a cleanup process
I've been meaning to do anyway.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: "Alex Nixon (Intern)" <Alex.Nixon@eu.citrix.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-31 12:39:39 +02:00
Jeremy Fitzhardinge d89961e2dc xen: suppress known wrmsrs
In general, Xen doesn't support wrmsr from an unprivileged domain; it
just ends up ignoring the instruction and printing a message on the
console.

Given that there are sets of MSRs we know the kernel will try to write
to, but we don't care, just eat them in xen_write_msr to cut down on
console noise.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-28 16:33:08 +02:00
Jeremy Fitzhardinge a05d2ebab2 xen: fix allocation and use of large ldts
When the ldt gets to more than 1 page in size, the kernel uses vmalloc
to allocate it.  This means that:

 - when making the ldt RO, we must update the pages in both the vmalloc
   mapping and the linear mapping to make sure there are no RW aliases.

 - we need to use arbitrary_virt_to_machine to compute the machine addr
   for each update

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-28 14:26:27 +02:00
Eduardo Habkost b56afe1d41 x86, xen: Use native_pte_flags instead of native_pte_val for .pte_flags
Using native_pte_val triggers the BUG_ON() in the paravirt_ops
version of pte_flags().

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-26 17:49:33 +02:00
Ingo Molnar 10a010f695 Merge branch 'linus' into x86/x2apic
Conflicts:

	drivers/pci/dmar.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-25 13:08:16 +02:00
Jeremy Fitzhardinge 38ffbe66d5 x86/paravirt/xen: properly fill out the ldt ops
LTP testing showed that Xen does not properly implement
sys_modify_ldt().  This patch does the final little bits needed to
make the ldt work properly.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-24 12:30:06 +02:00
Jeremy Fitzhardinge 59438c9fc4 x86: rename PTE_MASK to PTE_PFN_MASK
Rusty, in his peevish way, complained that macros defining constants
should have a name which somewhat accurately reflects the actual
purpose of the constant.

Aside from the fact that PTE_MASK gives no clue as to what's actually
being masked, and is misleadingly similar to the functionally entirely
different PMD_MASK, PUD_MASK and PGD_MASK, I don't really see what the
problem is.

But if this patch silences the incessent noise, then it will have
achieved its goal (TODO: write test-case).

Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-22 10:43:44 +02:00
Ingo Molnar 76c3bb15d6 Merge branch 'linus' into x86/x2apic 2008-07-22 09:06:21 +02:00
Ingo Molnar acee709cab Merge branches 'x86/urgent', 'x86/amd-iommu', 'x86/apic', 'x86/cleanups', 'x86/core', 'x86/cpu', 'x86/fixmap', 'x86/gart', 'x86/kprobes', 'x86/memtest', 'x86/modules', 'x86/nmi', 'x86/pat', 'x86/reboot', 'x86/setup', 'x86/step', 'x86/unify-pci', 'x86/uv', 'x86/xen' and 'xen-64bit' into x86/for-linus 2008-07-21 16:37:17 +02:00
Ingo Molnar caf43bf7c6 x86, xen: fix apic_ops build on UP
fix:

 arch/x86/xen/enlighten.c:615: error: variable ‘xen_basic_apic_ops’ has initializer but incomplete type
 arch/x86/xen/enlighten.c:616: error: unknown field ‘read’ specified in initializer
 [...]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-20 14:05:31 +02:00
Ingo Molnar 453c1404c5 Merge branch 'x86/apic' into x86/x2apic
Conflicts:

	arch/x86/kernel/paravirt.c
	arch/x86/kernel/smpboot.c
	arch/x86/kernel/vmi_32.c
	arch/x86/lguest/boot.c
	arch/x86/xen/enlighten.c
	include/asm-x86/apic.h
	include/asm-x86/paravirt.h

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 23:00:05 +02:00
Ingo Molnar a208f37a46 Merge branch 'linus' into x86/x2apic 2008-07-18 22:50:34 +02:00
Jeremy Fitzhardinge 95c7c23b06 xen: report hypervisor version
Various versions of the hypervisor have differences in what ABIs and
features they support.  Print some details into the boot log to help
with remote debugging.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 13:50:42 +02:00
Maciej W. Rozycki 593f4a788e x86: APIC: remove apic_write_around(); use alternatives
Use alternatives to select the workaround for the 11AP Pentium erratum
for the affected steppings on the fly rather than build time.  Remove the
X86_GOOD_APIC configuration option and replace all the calls to
apic_write_around() with plain apic_write(), protecting accesses to the
ESR as appropriate due to the 3AP Pentium erratum.  Remove
apic_read_around() and all its invocations altogether as not needed.
Remove apic_write_atomic() and all its implementing backends.  The use of
ASM_OUTPUT2() is not strictly needed for input constraints, but I have
used it for readability's sake.

I had the feeling no one else was brave enough to do it, so I went ahead
and here it is.  Verified by checking the generated assembly and tested
with both a 32-bit and a 64-bit configuration, also with the 11AP
"feature" forced on and verified with gdb on /proc/kcore to work as
expected (as an 11AP machines are quite hard to get hands on these days).
Some script complained about the use of "volatile", but apic_write() needs
it for the same reason and is effectively a replacement for writel(), so I
have disregarded it.

I am not sure what the policy wrt defconfig files is, they are generated
and there is risk of a conflict resulting from an unrelated change, so I
have left changes to them out.  The option will get removed from them at
the next run.

Some testing with machines other than mine will be needed to avoid some
stupid mistake, but despite its volume, the change is not really that
intrusive, so I am fairly confident that because it works for me, it will
everywhere.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-18 12:51:21 +02:00
Ingo Molnar b3fe124389 xen64: fix build error on 32-bit + !HIGHMEM
fix:

arch/x86/xen/enlighten.c: In function 'xen_set_fixmap':
arch/x86/xen/enlighten.c:1127: error: 'FIX_KMAP_BEGIN' undeclared (first use in this function)
arch/x86/xen/enlighten.c:1127: error: (Each undeclared identifier is reported only once
arch/x86/xen/enlighten.c:1127: error: for each function it appears in.)
arch/x86/xen/enlighten.c:1127: error: 'FIX_KMAP_END' undeclared (first use in this function)
make[1]: *** [arch/x86/xen/enlighten.o] Error 1
make: *** [arch/x86/xen/enlighten.o] Error 2

FIX_KMAP_BEGIN is only available on HIGHMEM.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:07:02 +02:00
Jeremy Fitzhardinge 1153968a48 xen: implement Xen write_msr operation
64-bit uses MSRs for important things like the base for fs and
gs-prefixed addresses.  It's more efficient to use a hypercall to
update these, rather than go via the trap and emulate path.

Other MSR writes are just passed through; in an unprivileged domain
they do nothing, but it might be useful later.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:06:20 +02:00
Jeremy Fitzhardinge bf18bf94dc xen64: set up userspace syscall patch
64-bit userspace expects the vdso to be mapped at a specific fixed
address, which happens to be in the middle of the kernel address
space.  Because we have split user and kernel pagetables, we need to
make special arrangements for the vsyscall mapping to appear in the
kernel part of the user pagetable.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:06:06 +02:00
Jeremy Fitzhardinge 6fcac6d305 xen64: set up syscall and sysenter entrypoints for 64-bit
We set up entrypoints for syscall and sysenter.  sysenter is only used
for 32-bit compat processes, whereas syscall can be used in by both 32
and 64-bit processes.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:05:52 +02:00
Jeremy Fitzhardinge d6182fbf04 xen64: allocate and manage user pagetables
Because the x86_64 architecture does not enforce segment limits, Xen
cannot protect itself with them as it does in 32-bit mode.  Therefore,
to protect itself, it runs the guest kernel in ring 3.  Since it also
runs the guest userspace in ring3, the guest kernel must maintain a
second pagetable for its userspace, which does not map kernel space.
Naturally, the guest kernel pagetables map both kernel and userspace.

The userspace pagetable is attached to the corresponding kernel
pagetable via the pgd's page->private field.  It is allocated and
freed at the same time as the kernel pgd via the
paravirt_pgd_alloc/free hooks.

Fortunately, the user pagetable is almost entirely shared with the
kernel pagetable; the only difference is the pgd page itself.  set_pgd
will populate all entries in the kernel pagetable, and also set the
corresponding user pgd entry if the address is less than
STACK_TOP_MAX.

The user pagetable must be pinned and unpinned with the kernel one,
but because the pagetables are aliased, pgd_walk() only needs to be
called on the kernel pagetable.  The user pgd page is then
pinned/unpinned along with the kernel pgd page.

xen_write_cr3 must write both the kernel and user cr3s.

The init_mm.pgd pagetable never has a user pagetable allocated for it,
because it can never be used while running usermode.

One awkward area is that early in boot the page structures are not
available.  No user pagetable can exist at that point, but it
complicates the logic to avoid looking at the page structure.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:05:38 +02:00
Eduardo Habkost 8a95408e18 xen64: Clear %fs on xen_load_tls()
We need to do this, otherwise we can get a GPF on hypercall return
after TLS descriptor is cleared but %fs is still pointing to it.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:04:55 +02:00
Jeremy Fitzhardinge b7c3c5c159 xen: make sure the kernel command line is right
Point the boot params cmd_line_ptr to the domain-builder-provided
command line.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:04:13 +02:00
Eduardo Habkost a8fc1089e4 xen64: implement xen_load_gs_index()
xen-64: implement xen_load_gs_index()

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:03:45 +02:00
Jeremy Fitzhardinge 0725cbb977 xen64: add identity irq->vector map
The x86_64 interrupt subsystem is oriented towards vectors, as opposed
to a flat irq space as it is in x86-32.  This patch adds a simple
identity irq->vector mapping so that we can continue to feed irqs into
do_IRQ() and get a good result.

Ideally x86_32 will unify with the 64-bit code and use vectors too.
At that point we can move to mapping event channels to vectors, which
will allow us to economise on irqs (so per-cpu event channels can
share irqs, rather than having to allocte one per cpu, for example).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:03:16 +02:00
Jeremy Fitzhardinge 952d1d7055 xen64: add pvop for swapgs
swapgs is a no-op under Xen, because the hypervisor makes sure the
right version of %gs is current when switching between user and kernel
modes.  This means that the swapgs "implementation" can be inlined and
used when the stack is unsafe (usermode).  Unfortunately, it means
that disabling patching will result in a non-booting kernel...

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:02:46 +02:00
Jeremy Fitzhardinge 997409d3d0 xen64: deal with extra words Xen pushes onto exception frames
Xen pushes two extra words containing the values of rcx and r11.  This
pvop hook copies the words back into their appropriate registers, and
cleans them off the stack.  This leaves the stack in native form, so
the normal handler can run unchanged.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:02:31 +02:00
Eduardo Habkost e176d367d0 xen64: xen_write_idt_entry() and cvt_gate_to_trap()
Changed to use the (to-be-)unified descriptor structs.

Signed-off-by: Eduardo Habkost <ehabkost@Rawhide-64.localdomain>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:02:15 +02:00
Jeremy Fitzhardinge 8745f8b0b9 xen64: defer setting pagetable alloc/release ops
We need to wait until the page structure is available to use the
proper pagetable page alloc/release operations, since they use struct
page to determine if a pagetable is pinned.

This happened to work in 32bit because nobody allocated new pagetable
pages in the interim between xen_pagetable_setup_done and
xen_post_allocator_init, but the 64-bit kenrel needs to allocate more
pagetable levels.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:01:45 +02:00
Jeremy Fitzhardinge 39dbc5bd34 xen32: create initial mappings like 64-bit
Rearrange the pagetable initialization to share code with the 64-bit
kernel.  Rather than deferring anything to pagetable_setup_start, just
set up an initial pagetable in swapper_pg_dir early at startup, and
create an additional 8MB of physical memory mappings.  This matches
the native head_32.S mappings to a large degree, and allows the rest
of the pagetable setup to continue without much Xen vs. native
difference.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:00:49 +02:00
Jeremy Fitzhardinge d114e1981c xen64: map an initial chunk of physical memory
Early in boot, map a chunk of extra physical memory for use later on.
We need a pool of mapped pages to allocate further pages to construct
pagetables mapping all physical memory.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:00:35 +02:00
Jeremy Fitzhardinge 22911b3f1c xen64: 64-bit starts using set_pte from very early
It also doesn't need the 32-bit hack version of set_pte for initial
pagetable construction, so just make it use the real thing.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:00:21 +02:00
Jeremy Fitzhardinge 084a2a4e76 xen64: early mapping setup
Set up the initial pagetables to map the kernel mapping into the
physical mapping space.  This makes __va() usable, since it requires
physical mappings.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 11:00:07 +02:00
Jeremy Fitzhardinge 7d087b68d6 xen: cpu_detect is 32-bit only
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:59:38 +02:00
Jeremy Fitzhardinge 15664f968a xen64: use set_fixmap for shared_info structure
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:59:24 +02:00
Jeremy Fitzhardinge 5b09b2876e x86_64: add workaround for no %gs-based percpu
As a stopgap until Mike Travis's x86-64 gs-based percpu patches are
ready, provide workaround functions for x86_read/write_percpu for
Xen's use.

Specifically, this means that we can't really make use of vcpu
placement, because we can't use a single gs-based memory access to get
to vcpu fields.  So disable all that for now.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:58:13 +02:00
Jeremy Fitzhardinge a9e7062d73 xen: move smp setup into smp.c
Move all the smp_ops setup into smp.c, allowing a lot of things to
become static.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:57:59 +02:00
Jeremy Fitzhardinge f5d36de069 xen64: random ifdefs to mask out 32-bit only code
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:57:30 +02:00
Jeremy Fitzhardinge f6e587325b xen64: add extra pv_mmu_ops
We need extra pv_mmu_ops for 64-bit, to deal with the extra level of
pagetable.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:57:16 +02:00
Jeremy Fitzhardinge 851fa3c4e7 xen: define set_pte from the outset
We need set_pte to work from a relatively early point, so enable it
from the start.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:56:04 +02:00
Eduardo Habkost a312b37b2a x86/paravirt: call paravirt_pagetable_setup_{start, done}
Call paravirt_pagetable_setup_{start,done}

These paravirt_ops functions were not being called on x86_64.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16 10:53:43 +02:00
Ingo Molnar 1a781a777b Merge branch 'generic-ipi' into generic-ipi-for-linus
Conflicts:

	arch/powerpc/Kconfig
	arch/s390/kernel/time.c
	arch/x86/kernel/apic_32.c
	arch/x86/kernel/cpu/perfctr-watchdog.c
	arch/x86/kernel/i8259_64.c
	arch/x86/kernel/ldt.c
	arch/x86/kernel/nmi_64.c
	arch/x86/kernel/smpboot.c
	arch/x86/xen/smp.c
	include/asm-x86/hw_irq_32.h
	include/asm-x86/hw_irq_64.h
	include/asm-x86/mach-default/irq_vectors.h
	include/asm-x86/mach-voyager/irq_vectors.h
	include/asm-x86/smp.h
	kernel/Makefile

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-15 21:55:59 +02:00
Yinghai Lu 94a8c3c243 x86: let 32bit use apic_ops too - fix
fix for pv - clean up the namespace there too.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-14 09:02:54 +02:00
Suresh Siddha ad66dd340f x2apic: xen64 paravirt basic apic ops
Define the Xen specific basic apic ops, in additon to paravirt apic ops,
with some misc warning fixes.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: akpm@linux-foundation.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-12 08:45:10 +02:00
Alok Kataria e93ef949fd x86: rename paravirtualized TSC functions
Rename the paravirtualized calculate_cpu_khz to calibrate_tsc.
In all cases, we actually calibrate_tsc and use that as the cpu_khz value.

Signed-off-by: Alok N Kataria <akataria@vmware.com>
Signed-off-by: Dan Hecht <dhecht@vmware.com>
Cc: Dan Hecht <dhecht@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-09 07:43:28 +02:00
Jeremy Fitzhardinge fab58420ac x86/paravirt, 64-bit: add adjust_exception_frame
64-bit Xen pushes a couple of extra words onto an exception frame.
Add a hook to deal with them.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 13:15:57 +02:00
Jeremy Fitzhardinge d75cd22fdd x86/paravirt: split sysret and sysexit
Don't conflate sysret and sysexit; they're different instructions with
different semantics, and may be in use at the same time (at least
within the same kernel, depending on whether its an Intel or AMD
system).

sysexit - just return to userspace, does no register restoration of
    any kind; must explicitly atomically enable interrupts.

sysret - reloads flags from r11, so no need to explicitly enable
    interrupts on 64-bit, responsible for restoring usermode %gs

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citirx.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 13:13:15 +02:00
Jeremy Fitzhardinge eba0045ff8 x86/paravirt: add a pgd_alloc/free hooks
Add hooks which are called at pgd_alloc/free time.  The pgd_alloc hook
may return an error code, which if non-zero, causes the pgd allocation
to be failed.  The hooks may be used to allocate/free auxillary
per-pgd information.

also fix:

> * Ingo Molnar <mingo@elte.hu> wrote:
>
>  include/asm/pgalloc.h: In function ‘paravirt_pgd_free':
>  include/asm/pgalloc.h:14: error: parameter name omitted
>  arch/x86/kernel/entry_64.S: In file included from
>  arch/x86/kernel/traps_64.c:51:include/asm/pgalloc.h: In function ‘paravirt_pgd_free':
>  include/asm/pgalloc.h:14: error: parameter name omitted

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 13:11:01 +02:00
Jeremy Fitzhardinge 88a6846c70 xen: set max_pfn_mapped
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: the arch/x86 maintainers <x86@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 12:48:30 +02:00
Ingo Molnar 6236af82d8 Merge branch 'x86/fixmap' into x86/devel
Conflicts:

	arch/x86/mm/init_64.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 12:24:29 +02:00
Ingo Molnar 3de352bbd8 Merge branch 'x86/mpparse' into x86/devel
Conflicts:

	arch/x86/Kconfig
	arch/x86/kernel/io_apic_32.c
	arch/x86/kernel/setup_64.c
	arch/x86/mm/init_32.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-08 11:14:58 +02:00
Ingo Molnar 896395c290 Merge branch 'linus' into tmp.x86.mpparse.new 2008-07-08 10:32:56 +02:00
Jens Axboe 3b16cf8748 x86: convert to generic helpers for IPI function calls
This converts x86, x86-64, and xen to use the new helpers for
smp_call_function() and friends, and adds support for
smp_call_function_single().

Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-26 11:21:54 +02:00
Jeremy Fitzhardinge e57778a1e3 xen: implement ptep_modify_prot_start/commit
Xen has a pte update function which will update a pte while preserving
its accessed and dirty bits.  This means that ptep_modify_prot_start() can be
implemented as a simple read of the pte value.  The hardware may
update the pte in the meantime, but ptep_modify_prot_commit() updates it while
preserving any changes that may have happened in the meantime.

The updates in ptep_modify_prot_commit() are batched if we're currently in lazy
mmu mode.

The mmu_update hypercall can take a batch of updates to perform, but
this code doesn't make particular use of that feature, in favour of
using generic multicall batching to get them all into the hypervisor.

The net effect of this is that each mprotect pte update turns from two
expensive trap-and-emulate faults into they hypervisor into a single
hypercall whose cost is amortized in a batched multicall.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-25 15:17:23 +02:00
Jeremy Fitzhardinge 08b882c627 paravirt: add hooks for ptep_modify_prot_start/commit
This patch adds paravirt-ops hooks in pv_mmu_ops for ptep_modify_prot_start and
ptep_modify_prot_commit.  This allows the hypervisor-specific backends to
implement these in some more efficient way.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-25 15:16:00 +02:00
Ingo Molnar 8b7ef4ec5b Merge branch 'linus' into x86/fixmap 2008-06-25 12:30:21 +02:00
Jeremy Fitzhardinge 2849914393 xen: remove support for non-PAE 32-bit
Non-PAE operation has been deprecated in Xen for a while, and is
rarely tested or used.  xen-unstable has now officially dropped
non-PAE support.  Since Xen/pvops' non-PAE support has also been
broken for a while, we may as well completely drop it altogether.

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>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-24 17:00:55 +02:00
Jeremy Fitzhardinge aeaaa59c7e x86/paravirt/xen: add set_fixmap pv_mmu_ops
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-20 15:09:56 +02:00
Jeremy Fitzhardinge 05345b0f00 xen: mask unwanted pte bits in __supported_pte_mask
[ Stable: this isn't a bugfix in itself, but it's a pre-requiste
  for "xen: don't drop NX bit" ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: the arch/x86 maintainers <x86@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-20 14:56:36 +02:00
Jeremy Fitzhardinge eb179e443d xen: mask unwanted pte bits in __supported_pte_mask
[ Stable: this isn't a bugfix in itself, but it's a pre-requiste
  for "xen: don't drop NX bit" ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: the arch/x86 maintainers <x86@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-20 14:55:11 +02:00
Jeremy Fitzhardinge 9c7a794209 xen: restore vcpu_info mapping
If we're using vcpu_info mapping, then make sure its restored on all
processors before relasing them from stop_machine.

The only complication is that if this fails, we can't continue because
we've already made assumptions that the mapping is available (baked in
calls to the _direct versions of the functions, for example).

Fortunately this can only happen with a 32-bit hypervisor, which may
possibly run out of mapping space.  On a 64-bit hypervisor, this is a
non-issue.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02 13:25:34 +02:00
Jeremy Fitzhardinge e2426cf85f xen: avoid hypercalls when updating unpinned pud/pmd
When operating on an unpinned pagetable (ie, one under construction or
destruction), it isn't necessary to use a hypercall to update a
pud/pmd entry.  Jan Beulich observed that a similar optimisation
avoided many thousands of hypercalls while doing a kernel build.

One tricky part is that early in the kernel boot there's no page
structure, so we can't check to see if the page is pinned.  In that
case, we just always use the hypercall.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02 13:24:40 +02:00
Yinghai Lu f0d43100f1 x86: extend e820 early_res support 32bit -fix #3
introduce init_pg_table_start, so xen PV could specify the value.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-05-31 09:55:47 +02:00
Jeremy Fitzhardinge 0e91398f2a xen: implement save/restore
This patch implements Xen save/restore and migration.

Saving is triggered via xenbus, which is polled in
drivers/xen/manage.c.  When a suspend request comes in, the kernel
prepares itself for saving by:

1 - Freeze all processes.  This is primarily to prevent any
    partially-completed pagetable updates from confusing the suspend
    process.  If CONFIG_PREEMPT isn't defined, then this isn't necessary.

2 - Suspend xenbus and other devices

3 - Stop_machine, to make sure all the other vcpus are quiescent.  The
    Xen tools require the domain to run its save off vcpu0.

4 - Within the stop_machine state, it pins any unpinned pgds (under
    construction or destruction), performs canonicalizes various other
    pieces of state (mostly converting mfns to pfns), and finally

5 - Suspend the domain

Restore reverses the steps used to save the domain, ending when all
the frozen processes are thawed.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:38 +02:00
Jeremy Fitzhardinge d5edbc1f75 xen: add p2m mfn_list_list
When saving a domain, the Xen tools need to remap all our mfns to
portable pfns.  In order to remap our p2m table, it needs to know
where all its pages are, so maintain the references to the p2m table
for it to use.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:37 +02:00
Jeremy Fitzhardinge a0d695c821 xen: make dummy_shared_info non-static
Rename dummy_shared_info to xen_dummy_shared_info and make it
non-static, in anticipation of users outside of enlighten.c

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:37 +02:00
Jeremy Fitzhardinge d451bb7aa8 xen: make phys_to_machine structure dynamic
We now support the use of memory hotplug, so the physical to machine
page mapping structure must be dynamic.  This is implemented as a
two-level radix tree structure, which allows us to efficiently
incrementally allocate memory for the p2m table as new pages are
added.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:37 +02:00
Jeremy Fitzhardinge 83abc70a4c xen: make earlyprintk=xen work again
For some perverse reason, if you call add_preferred_console() it prevents
setup_early_printk() from successfully enabling the boot console -
unless you make it a preferred console too...

Also, make xenboot console output distinct from normal console output,
since it gets repeated when the console handover happens, and the
duplicated output is confusing without disambiguation.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
2008-05-27 10:11:36 +02:00
Markus Armbruster 9e124fe16f xen: Enable console tty by default in domU if it's not a dummy
Without console= arguments on the kernel command line, the first
console to register becomes enabled and the preferred console (the one
behind /dev/console).  This is normally tty (assuming
CONFIG_VT_CONSOLE is enabled, which it commonly is).

This is okay as long tty is a useful console.  But unless we have the
PV framebuffer, and it is enabled for this domain, tty0 in domU is
merely a dummy.  In that case, we want the preferred console to be the
Xen console hvc0, and we want it without having to fiddle with the
kernel command line.  Commit b8c2d3dfbc
did that for us.

Since we now have the PV framebuffer, we want to enable and prefer tty
again, but only when PVFB is enabled.  But even then we still want to
enable the Xen console as well.

Problem: when tty registers, we can't yet know whether the PVFB is
enabled.  By the time we can know (xenstore is up), the console setup
game is over.

Solution: enable console tty by default, but keep hvc as the preferred
console.  Change the preferred console to tty when PVFB probes
successfully, unless we've been given console kernel parameters.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:36 +02:00
Jeremy Fitzhardinge a15af1c9ea x86/paravirt: add pte_flags to just get pte flags
Add pte_flags() to extract the flags from a pte.  This is a special
case of pte_val() which is only guaranteed to return the pte's flags
correctly; the page number may be corrupted or missing.

The intent is to allow paravirt implementations to return pte flags
without having to do any translation of the page number (most notably,
Xen).

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:36 +02:00
Jeremy Fitzhardinge 239d1fc04e xen: don't worry about preempt during xen_irq_enable()
When enabling interrupts, we don't need to worry about preemption,
because we either enter with interrupts disabled - so no preemption -
or the caller is confused and is re-enabling interrupts on some
indeterminate processor.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:35 +02:00
Jeremy Fitzhardinge 2956a3511c xen: allow some cr4 updates
The guest can legitimately change things like cr4.OSFXSR and
OSXMMEXCPT, so let it.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:35 +02:00
Jeremy Fitzhardinge 349c709f42 xen: use new sched_op
Use the new sched_op hypercall, mainly because xenner doesn't support
the old one.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:35 +02:00
Jeremy Fitzhardinge 7b1333aa4c xen: use hypercall rather than clts
Xen will trap and emulate clts, but its better to use a hypercall.
Also, xenner doesn't handle clts.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-05-27 10:11:35 +02:00
Jeremy Fitzhardinge 3843fc2575 xen: remove support for non-PAE 32-bit
Non-PAE operation has been deprecated in Xen for a while, and is
rarely tested or used.  xen-unstable has now officially dropped
non-PAE support.  Since Xen/pvops' non-PAE support has also been
broken for a while, we may as well completely drop it altogether.

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>
2008-05-22 18:42:49 +02:00
Jeremy Fitzhardinge af7ae3b9c4 xen: allow compilation with non-flat memory
There's no real reason we can't support sparsemem/discontigmem, so do so.
This is mostly useful to support hotplug memory.

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 41e332b2a2 xen: disable preemption during tlb flush
Various places in the kernel flush the tlb even though preemption doens't
guarantee the tlb flush is happening on any particular CPU.  In many cases
this doesn't seem to matter, so don't make a fuss about it.

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 dbe9e994c9 xen: no need for domU to worry about MCE/MCA
Mask MCE/MCA out of cpu caps.  Its harmless to leave them there, but
it does prevent the kernel from starting an unnecessary thread.

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
Jeremy Fitzhardinge e2a81baf66 xen: support sysenter/sysexit if hypervisor does
64-bit Xen supports sysenter for 32-bit guests, so support its
use.  (sysenter is faster than int $0x80 in 32-on-64.)

sysexit is still not supported, so we fake it up using iret.

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 23:57:31 +02:00
Jeremy Fitzhardinge 6944a9c894 x86: rename paravirt_alloc_pt etc after the pagetable structure
Rename (alloc|release)_(pt|pd) to pte/pmd to explicitly match the name
of the appropriate pagetable level structure.

[ x86.git merge work 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: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-24 23:57:31 +02:00
Jeremy Fitzhardinge 81e103f1f1 xen: use iret instruction all the time
Change iret implementation to not be dependent on direct-access vcpu
structure.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Markus Armbruster b8c2d3dfbc xen: make hvc0 the preferred console in domU
This makes the Xen console just work.  Before, you had to ask for it
on the kernel command line with console=hvc0

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-17 17:40:51 +02:00
Mark McLoughlin c946c7de49 xen: Clear PG_pinned in release_{pt,pd}()
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: xen-devel@lists.xensource.com
Cc: Mark McLoughlin <markmc@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-04 18:36:48 +02:00
Mark McLoughlin a684d69d15 xen: Do not pin/unpin PMD pages
i.e. with this simple test case:

    int fd = open("/dev/zero", O_RDONLY);
    munmap(mmap((void *)0x40000000, 0x1000_LEN, PROT_READ, MAP_PRIVATE, fd, 0), 0x1000);
    close(fd);

we currently get:

   kernel BUG at arch/x86/xen/enlighten.c:678!
   ...
   EIP is at xen_release_pt+0x79/0xa9
   ...
   Call Trace:
    [<c041da25>] ? __pmd_free_tlb+0x1a/0x75
    [<c047a192>] ? free_pgd_range+0x1d2/0x2b5
    [<c047a2f3>] ? free_pgtables+0x7e/0x93
    [<c047b272>] ? unmap_region+0xb9/0xf5
    [<c047c1bd>] ? do_munmap+0x193/0x1f5
    [<c047c24f>] ? sys_munmap+0x30/0x3f
    [<c0408cce>] ? syscall_call+0x7/0xb
    =======================

and xen complains:

  (XEN) mm.c:2241:d4 Mfn 1cc37 not pinned

Further details at:

  https://bugzilla.redhat.com/436453

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: xen-devel@lists.xensource.com
Cc: Mark McLoughlin <markmc@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-04 18:36:48 +02:00
Mark McLoughlin f64337062c xen: refactor xen_{alloc,release}_{pt,pd}()
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: xen-devel@lists.xensource.com
Cc: Mark McLoughlin <markmc@redhat.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-04 18:36:48 +02:00
Jeremy Fitzhardinge 2e8fe719b5 xen: fix UP setup of shared_info
We need to set up the shared_info pointer once we've mapped the real
shared_info into its fixmap slot.  That needs to happen once the general
pagetable setup has been done.  Previously, the UP shared_info was set
up one in xen_start_kernel, but that was left pointing to the dummy
shared info.  Unfortunately there's no really good place to do a later
setup of the shared_info in UP, so just do it once the pagetable setup
has been done.

[ Stable: needed in 2.6.24.x ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-27 16:08:45 +01:00
Jeremy Fitzhardinge 04c44a080d xen: fix RMW when unmasking events
xen_irq_enable_direct and xen_sysexit were using "andw $0x00ff,
XEN_vcpu_info_pending(vcpu)" to unmask events and test for pending ones
in one instuction.

Unfortunately, the pending flag must be modified with a locked operation
since it can be set by another CPU, and the unlocked form of this
operation was causing the pending flag to get lost, allowing the processor
to return to usermode with pending events and ultimately deadlock.

The simple fix would be to make it a locked operation, but that's rather
costly and unnecessary.  The fix here is to split the mask-clearing and
pending-testing into two instructions; the interrupt window between
them is of no concern because either way pending or new events will
be processed.

This should fix lingering bugs in using direct vcpu structure access too.

[ Stable: needed in 2.6.24.x ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-27 16:08:45 +01:00
Jeremy Fitzhardinge d40e705903 xen: mask out SEP from CPUID
Fix 32-on-64 pvops kernel:

we don't want userspace using syscall/sysenter, even if the hypervisor
supports it, so mask it out from CPUID.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-29 18:55:43 +01:00
Jeremy Fitzhardinge 2b5407811d xen: unpin initial Xen pagetable once we're finished with it
Unpin the Xen-provided pagetable once we've finished with it, so it
doesn't cause stray references which cause later swapper_pg_dir
pagetable updates to fail.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Tested-by: Jody Belka <knew-linux@pimb.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-02-13 16:20:35 +01:00
Jeremy Fitzhardinge 1c70e9bd83 xen: deal with pmd being allocated/freed
Deal properly with pmd-level pages being allocated and freed
dynamically.  We can handle them more or less the same as pte pages.

Also, deal with early_ioremap pagetable manipulations.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:33:39 +01:00
Jan Beulich 4dbf7af644 x86: adjust/fix LDT handling for Xen
Based on patch from Jan Beulich <jbeulich@novell.com>.

Don't rely on kmalloc(PAGE_SIZE) returning PAGE_SIZE aligned memory
(Xen requires GDT *and* LDT to be page-aligned). Using the page
allocator interface also removes the (albeit small) slab allocator
overhead. The same change being done for 64-bits for consistency.

Further, the Xen hypercall interface expects the LDT address to be
virtual, not machine.

[ Adjusted to unified ldt.c - Jeremy ]

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:33:14 +01:00
Glauber de Oliveira Costa 75b8bb3e56 x86: change write_ldt_entry signature
this patch changes the signature of write_ldt_entry.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
CC: Zachary Amsden <zach@vmware.com>
CC: Jeremy Fitzhardinge <Jeremy.Fitzhardinge.citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:13 +01:00
Glauber de Oliveira Costa 014b15be30 x86: change write_gdt_entry signature.
This patch changes the write_gdt_entry function signature.
Instead of the old "a" and "b" parameters, it now receives
a pointer to a desc_struct, and the size of the entry being
handled. This is because x86_64 can have some 16-byte entries
as well as 8-byte ones.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
CC: Zachary Amsden <zach@vmware.com>
CC: Jeremy Fitzhardinge <Jeremy.Fitzhardinge.citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:13 +01:00
Glauber de Oliveira Costa 8d947344c4 x86: change write_idt_entry signature
this patch changes write_idt_entry signature. It now takes a gate_desc
instead of the a and b parameters. It will allow it to be later unified
between i386 and x86_64.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
CC: Zachary Amsden <zach@vmware.com>
CC: Jeremy Fitzhardinge <Jeremy.Fitzhardinge.citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:12 +01:00
Glauber de Oliveira Costa 6b68f01baa x86: unify struct desc_ptr
This patch unifies struct desc_ptr between i386 and x86_64.
They can be expressed in the exact same way in C code, only
having to change the name of one of them. As Xgt_desc_struct
is ugly and big, this is the one that goes away.

There's also a padding field in i386, but it is not really
needed in the C structure definition.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:12 +01:00
H. Peter Anvin faca62273b x86: use generic register name in the thread and tss structures
This changes size-specific register names (eip/rip, esp/rsp, etc.) to
generic names in the thread and tss structures.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:31:02 +01:00
H. Peter Anvin 65ea5b0349 x86: rename the struct pt_regs members for 32/64-bit consistency
We have a lot of code which differs only by the naming of specific
members of structures that contain registers.  In order to enable
additional unifications, this patch drops the e- or r- size prefix
from the register names in struct pt_regs, and drops the x- prefixes
for segment registers on the 32-bit side.

This patch also performs the equivalent renames in some additional
places that might be candidates for unification in the future.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:56 +01:00
Glauber de Oliveira Costa 6abcd98ffa x86: irqflags consolidation
This patch consolidates the irqflags include files containing common
paravirt definitions. The native definition for interrupt handling, halt,
and such, are the same for 32 and 64 bit, and they are kept in irqflags.h.
the differences are split in the arch-specific files.

The syscall function, irq_enable_sysexit, has a very specific i386 naming,
and its name is then changed to a more general one.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-01-30 13:30:33 +01:00
Thomas Gleixner 42e0a9aa5d x86: use u32 for some lapic functions
Use u32 so 32 and 64bit have the same interface.

Andrew Morton: xen, lguest build fixes

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-01-30 13:30:15 +01:00
Jeremy Fitzhardinge f9c4cfe954 xen: disable vcpu_info placement for now
There have been several reports of Xen guest domains locking up when
using vcpu_info structure placement.  Disable it for now.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-23 18:04:54 -08:00
Jeremy Fitzhardinge 7999f4b4e5 xen: relax signature check
Some versions of Xen 3.x set their magic number to "xen-3.[12]", so
relax the test to match them.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-12-10 19:46:58 -08:00
Linus Torvalds fb9fc39517 Merge branch 'xen-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'xen-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xfs: eagerly remove vmap mappings to avoid upsetting Xen
  xen: add some debug output for failed multicalls
  xen: fix incorrect vcpu_register_vcpu_info hypercall argument
  xen: ask the hypervisor how much space it needs reserved
  xen: lock pte pages while pinning/unpinning
  xen: deal with stale cr3 values when unpinning pagetables
  xen: add batch completion callbacks
  xen: yield to IPI target if necessary
  Clean up duplicate includes in arch/i386/xen/
  remove dead code in pgtable_cache_init
  paravirt: clean up lazy mode handling
  paravirt: refactor struct paravirt_ops into smaller pv_*_ops
2007-10-17 11:10:11 -07:00
H. Peter Anvin 30c826451d [x86] remove uses of magic macros for boot_params access
Instead of using magic macros for boot_params access, simply use the
boot_params structure.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2007-10-16 17:38:31 -07:00
Jeremy Fitzhardinge e3d2697669 xen: fix incorrect vcpu_register_vcpu_info hypercall argument
The kernel's copy of struct vcpu_register_vcpu_info was out of date,
at best causing the hypercall to fail and the guest kernel to fall
back to the old mechanism, or worse, causing random memory corruption.

[ Stable folks: applies to 2.6.23 ]

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Stable Kernel <stable@kernel.org>
Cc: Morten =?utf-8?q?B=C3=B8geskov?= <xen-users@morten.bogeskov.dk>
Cc: Mark Williamson <mark.williamson@cl.cam.ac.uk>
2007-10-16 11:51:31 -07:00
Jeremy Fitzhardinge fb1d84043c xen: ask the hypervisor how much space it needs reserved
Ask the hypervisor how much space it needs reserved, since 32-on-64
doesn't need any space, and it may change in future.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
2007-10-16 11:51:31 -07:00
Jeremy Fitzhardinge 74260714c5 xen: lock pte pages while pinning/unpinning
When a pagetable is created, it is made globally visible in the rmap
prio tree before it is pinned via arch_dup_mmap(), and remains in the
rmap tree while it is unpinned with arch_exit_mmap().

This means that other CPUs may race with the pinning/unpinning
process, and see a pte between when it gets marked RO and actually
pinned, causing any pte updates to fail with write-protect faults.

As a result, all pte pages must be properly locked, and only unlocked
once the pinning/unpinning process has finished.

In order to avoid taking spinlocks for the whole pagetable - which may
overflow the PREEMPT_BITS portion of preempt counter - it locks and pins
each pte page individually, and then finally pins the whole pagetable.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hugh Dickens <hugh@veritas.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Keir Fraser <keir@xensource.com>
Cc: Jan Beulich <jbeulich@novell.com>
2007-10-16 11:51:30 -07:00
Jeremy Fitzhardinge 9f79991d41 xen: deal with stale cr3 values when unpinning pagetables
When a pagetable is no longer in use, it must be unpinned so that its
pages can be freed.  However, this is only possible if there are no
stray uses of the pagetable.  The code currently deals with all the
usual cases, but there's a rare case where a vcpu is changing cr3, but
is doing so lazily, and the change hasn't actually happened by the time
the pagetable is unpinned, even though it appears to have been completed.

This change adds a second per-cpu cr3 variable - xen_current_cr3 -
which tracks the actual state of the vcpu cr3.  It is only updated once
the actual hypercall to set cr3 has been completed.  Other processors
wishing to unpin a pagetable can check other vcpu's xen_current_cr3
values to see if any cross-cpu IPIs are needed to clean things up.

[ Stable folks: 2.6.23 bugfix ]

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Stable Kernel <stable@kernel.org>
2007-10-16 11:51:30 -07:00
Jesper Juhl d626a1f1cb Clean up duplicate includes in arch/i386/xen/
This patch cleans up duplicate includes in
	arch/i386/xen/

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
2007-10-16 11:51:29 -07:00
Jeremy Fitzhardinge 8965c1c095 paravirt: clean up lazy mode handling
Currently, the set_lazy_mode pv_op is overloaded with 5 functions:
 1. enter lazy cpu mode
 2. leave lazy cpu mode
 3. enter lazy mmu mode
 4. leave lazy mmu mode
 5. flush pending batched operations

This complicates each paravirt backend, since it needs to deal with
all the possible state transitions, handling flushing, etc. In
particular, flushing is quite distinct from the other 4 functions, and
seems to just cause complication.

This patch removes the set_lazy_mode operation, and adds "enter" and
"leave" lazy mode operations on mmu_ops and cpu_ops.  All the logic
associated with enter and leaving lazy states is now in common code
(basically BUG_ONs to make sure that no mode is current when entering
a lazy mode, and make sure that the mode is current when leaving).
Also, flush is handled in a common way, by simply leaving and
re-entering the lazy mode.

The result is that the Xen, lguest and VMI lazy mode implementations
are much simpler.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Anthony Liguory <aliguori@us.ibm.com>
Cc: "Glauber de Oliveira Costa" <glommer@gmail.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>
2007-10-16 11:51:29 -07:00
Jeremy Fitzhardinge 93b1eab3d2 paravirt: refactor struct paravirt_ops into smaller pv_*_ops
This patch refactors the paravirt_ops structure into groups of
functionally related ops:

pv_info - random info, rather than function entrypoints
pv_init_ops - functions used at boot time (some for module_init too)
pv_misc_ops - lazy mode, which didn't fit well anywhere else
pv_time_ops - time-related functions
pv_cpu_ops - various privileged instruction ops
pv_irq_ops - operations for managing interrupt state
pv_apic_ops - APIC operations
pv_mmu_ops - operations for managing pagetables

There are several motivations for this:

1. Some of these ops will be general to all x86, and some will be
   i386/x86-64 specific.  This makes it easier to share common stuff
   while allowing separate implementations where needed.

2. At the moment we must export all of paravirt_ops, but modules only
   need selected parts of it.  This allows us to export on a case by case
   basis (and also choose which export license we want to apply).

3. Functional groupings make things a bit more readable.

Struct paravirt_ops is now only used as a template to generate
patch-site identifiers, and to extract function pointers for inserting
into jmp/calls when patching.  It is only instantiated when needed.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Anthony Liguory <aliguori@us.ibm.com>
Cc: "Glauber de Oliveira Costa" <glommer@gmail.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>
2007-10-16 11:51:29 -07:00
Thomas Gleixner 9702785a74 i386: move xen
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-11 11:16:51 +02:00