Commit Graph

134 Commits

Author SHA1 Message Date
Stefano Stabellini
eb1ddc00b8 swiotlb-xen: introduce xen_swiotlb_set_dma_mask
Implement xen_swiotlb_set_dma_mask, use it for set_dma_mask on arm.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-10-09 16:56:33 +00:00
Stefano Stabellini
83862ccfc0 xen/arm,arm64: enable SWIOTLB_XEN
Xen on arm and arm64 needs SWIOTLB_XEN: when running on Xen we need to
program the hardware with mfns rather than pfns for dma addresses.
Remove SWIOTLB_XEN dependency on X86 and PCI and make XEN select
SWIOTLB_XEN on arm and arm64.

At the moment always rely on swiotlb-xen, but when Xen starts supporting
hardware IOMMUs we'll be able to avoid it conditionally on the presence
of an IOMMU on the platform.

Implement xen_create_contiguous_region on arm and arm64: for the moment
we assume that dom0 has been mapped 1:1 (physical addresses == machine
addresses) therefore we don't need to call XENMEM_exchange. Simply
return the physical address as dma address.

Initialize the xen-swiotlb from xen_early_init (before the native
dma_ops are initialized), set xen_dma_ops to &xen_swiotlb_dma_ops.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>


Changes in v8:
- assume dom0 is mapped 1:1, no need to call XENMEM_exchange.

Changes in v7:
- call __set_phys_to_machine_multi from xen_create_contiguous_region and
xen_destroy_contiguous_region to update the P2M;
- don't call XENMEM_unpin, it has been removed;
- call XENMEM_exchange instead of XENMEM_exchange_and_pin;
- set nr_exchanged to 0 before calling the hypercall.

Changes in v6:
- introduce and export xen_dma_ops;
- call xen_mm_init from as arch_initcall.

Changes in v4:
- remove redefinition of DMA_ERROR_CODE;
- update the code to use XENMEM_exchange_and_pin and XENMEM_unpin;
- add a note about hardware IOMMU in the commit message.

Changes in v3:
- code style changes;
- warn on XENMEM_put_dma_buf failures.
2013-10-10 13:40:44 +00:00
Stefano Stabellini
4a19138c65 arm/xen,arm64/xen: introduce p2m
Introduce physical to machine and machine to physical tracking
mechanisms based on rbtrees for arm/xen and arm64/xen.

We need it because any guests on ARM are an autotranslate guests,
therefore a physical address is potentially different from a machine
address. When programming a device to do DMA, we need to be
extra-careful to use machine addresses rather than physical addresses to
program the device. Therefore we need to know the physical to machine
mappings.

For the moment we assume that dom0 starts with a 1:1 physical to machine
mapping, in other words physical addresses correspond to machine
addresses. However when mapping a foreign grant reference, obviously the
1:1 model doesn't work anymore. So at the very least we need to be able
to track grant mappings.

We need locking to protect accesses to the two trees.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Changes in v8:
- move pfn_to_mfn and mfn_to_pfn to page.h as static inline functions;
- no need to walk the tree if phys_to_mach.rb_node is NULL;
- correctly handle multipage p2m entries;
- substitute the spin_lock with a rwlock.
2013-10-17 16:22:27 +00:00
Konrad Rzeszutek Wilk
65320fceda Linux 3.11-rc7
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Merge tag 'v3.11-rc7' into stable/for-linus-3.12

Linux 3.11-rc7

As we need the git commit 28817e9de4f039a1a8c1fe1df2fa2df524626b9e
Author: Chuck Anderson <chuck.anderson@oracle.com>
Date:   Tue Aug 6 15:12:19 2013 -0700

    xen/smp: initialize IPI vectors before marking CPU online

* tag 'v3.11-rc7': (443 commits)
  Linux 3.11-rc7
  ARC: [lib] strchr breakage in Big-endian configuration
  VFS: collect_mounts() should return an ERR_PTR
  bfs: iget_locked() doesn't return an ERR_PTR
  efs: iget_locked() doesn't return an ERR_PTR()
  proc: kill the extra proc_readfd_common()->dir_emit_dots()
  cope with potentially long ->d_dname() output for shmem/hugetlb
  usb: phy: fix build breakage
  USB: OHCI: add missing PCI PM callbacks to ohci-pci.c
  staging: comedi: bug-fix NULL pointer dereference on failed attach
  lib/lz4: correct the LZ4 license
  memcg: get rid of swapaccount leftovers
  nilfs2: fix issue with counting number of bio requests for BIO_EOPNOTSUPP error detection
  nilfs2: remove double bio_put() in nilfs_end_bio_write() for BIO_EOPNOTSUPP error
  drivers/platform/olpc/olpc-ec.c: initialise earlier
  ipv4: expose IPV4_DEVCONF
  ipv6: handle Redirect ICMP Message with no Redirected Header option
  be2net: fix disabling TX in be_close()
  Revert "ACPI / video: Always call acpi_video_init_brightness() on init"
  Revert "genetlink: fix family dump race"
  ...

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-09-09 12:05:37 -04:00
Julien Grall
e1a9c16b30 xen/arm: disable cpuidle and cpufreq when linux is running as dom0
When linux is running as dom0, Xen doesn't show the physical cpu but a
virtual CPU.
On some ARM SOC (for instance the exynos 5250), linux registers callbacks
for cpuidle and cpufreq. When these callbacks are called, they will modify
directly the physical cpu not the virtual one. It can impact the whole board
instead of only dom0.

Signed-off-by: Julien Grall <julien.grall@linaro.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-09-09 11:35:26 +00:00
Rob Herring
9dd4b2944c ARM: xen: only set pm function ptrs for Xen guests
xen_pm_init was unconditionally setting pm_power_off and arm_pm_restart
function pointers. This breaks multi-platform kernels. Make this
conditional on running as a Xen guest and make it a late_initcall to
ensure it is setup after platform code for Dom0.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC: stable@vger.kernel.org
2013-09-09 10:50:26 +00:00
Linus Torvalds
d936d2d452 Bug-fixes:
- On ARM did not have balanced calls to get/put_cpu.
  - Fix to make tboot + Xen + Linux correctly.
  - Fix events VCPU binding issues.
  - Fix a vCPU online race where IPIs are sent to not-yet-online vCPU.
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Merge tag 'stable/for-linus-3.11-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
 - On ARM did not have balanced calls to get/put_cpu.
 - Fix to make tboot + Xen + Linux correctly.
 - Fix events VCPU binding issues.
 - Fix a vCPU online race where IPIs are sent to not-yet-online vCPU.

* tag 'stable/for-linus-3.11-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/smp: initialize IPI vectors before marking CPU online
  xen/events: mask events when changing their VCPU binding
  xen/events: initialize local per-cpu mask for all possible events
  x86/xen: do not identity map UNUSABLE regions in the machine E820
  xen/arm: missing put_cpu in xen_percpu_init
2013-08-21 16:38:33 -07:00
Julien Grall
0d7febe584 xen/arm: missing put_cpu in xen_percpu_init
When CONFIG_PREEMPT is enabled, Linux will not be able to boot and warn:
[    4.127825] ------------[ cut here ]------------
[    4.133376] WARNING: at init/main.c:699 do_one_initcall+0x150/0x158()
[    4.140738] initcall xen_init_events+0x0/0x10c returned with preemption imbalance

This is because xen_percpu_init uses get_cpu but doesn't have the corresponding
put_cpu.

Signed-off-by: Julien Grall <julien.grall@linaro.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-08-05 11:21:39 +00:00
Stefano Stabellini
2451ade070 xen/arm,arm64: update xen_restart after ff701306cd and 7b6d864b48
Commit 7b6d864b48 (reboot: arm: change reboot_mode to use enum
reboot_mode) and ff701306cd (arm64: use common reboot infrastructure)
change the prototype of arm_pm_restart on arm and arm64.
Update xen_restart accordingly.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-07-23 12:22:47 +00:00
Stefano Stabellini
176455e9a9 xen/arm and xen/arm64: implement HYPERVISOR_tmem_op
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-07-04 11:41:12 +00:00
Stefano Stabellini
3cc8e40e8f xen/arm: rename xen_secondary_init and run it on every online cpu
Rename xen_secondary_init to xen_percpu_init.
Run xen_percpu_init on the each online cpu, reuse the current on_each_cpu call.
Merge xen_percpu_enable_events into xen_percpu_init.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-05-13 16:14:25 +00:00
Stefano Stabellini
d7266d7894 xen/arm: do not handle VCPUOP_register_vcpu_info failures
We expect VCPUOP_register_vcpu_info to succeed, do not try to handle
failures.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
2013-05-13 16:14:22 +00:00
Stefano Stabellini
1aa3d8d993 xen/arm: initialize pm functions later
If we are running in dom0, we have to wait for the arch specific code to
complete the initialization in order for us to successfully reset the
power_off and pm_restart functions.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-05-13 16:13:04 +00:00
Wei Yongjun
9bc25a1d5f xen/arm: remove duplicated include from enlighten.c
Remove duplicated include.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
2013-04-27 14:57:17 +00:00
Stefano Stabellini
6abb749e83 xen/arm: use sched_op hypercalls for machine reboot and power off
Changes in v5:
- set pm_power_off and arm_pm_restart from the Xen specific
intialization code.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-04-25 16:46:10 +00:00
Stefano Stabellini
9a9ab3cc00 xen/arm: SMP support
Map vcpu_info using VCPUOP_register_vcpu_info on all the online vcpus,
make sure the allocated struct doesn't cross a page boundary.

Call enable_percpu_irq on every cpu.

Changes in v5:
- allocate xen_vcpu_info dynamically, aligning it to the size of the
struct;
- use VCPUOP_register_vcpu_info on cpu0 too.

Changed in v2:
- move the percpu variable argument fix to a separate patch;
- remove unused variable.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-04-25 16:46:07 +00:00
Stefano Stabellini
ea0af61321 xen/arm: implement HYPERVISOR_vcpu_op
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
2013-04-25 16:46:07 +00:00
Stefano Stabellini
2798ba7d19 xen/arm: actually pass a non-NULL percpu pointer to request_percpu_irq
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Ian Campbell <ian.camjpbell@citrix.com>
CC: stable@vger.kernel.org
2013-04-25 16:46:06 +00:00
Ian Campbell
07d0c94366 xen: implement updated XENMEM_add_to_physmap_range ABI
Allows for more fine grained error reporting. Only used by PVH and
ARM both of which are marked EXPERIMENTAL precisely because the ABI
is not yet stable

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[v1: Rebased without PVH patches]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-19 22:01:55 -05:00
Linus Torvalds
896ea17d3d Features:
- Add necessary infrastructure to make balloon driver work under ARM.
  - Add /dev/xen/privcmd interfaces to work with ARM and PVH.
  - Improve Xen PCIBack wild-card parsing.
  - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/online
    sockets depending on the power consumption.
  - PVHVM + kexec = use an E820_RESV region for the shared region so we don't
    overwrite said region during kexec reboot.
  - Cleanups, compile fixes.
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Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen updates from Konrad Rzeszutek Wilk:
 - Add necessary infrastructure to make balloon driver work under ARM.
 - Add /dev/xen/privcmd interfaces to work with ARM and PVH.
 - Improve Xen PCIBack wild-card parsing.
 - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/
   online sockets depending on the power consumption.
 - PVHVM + kexec = use an E820_RESV region for the shared region so we
   don't overwrite said region during kexec reboot.
 - Cleanups, compile fixes.

Fix up some trivial conflicts due to the balloon driver now working on
ARM, and there were changes next to the previous work-arounds that are
now gone.

* tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/PVonHVM: fix compile warning in init_hvm_pv_info
  xen: arm: implement remap interfaces needed for privcmd mappings.
  xen: correctly use xen_pfn_t in remap_domain_mfn_range.
  xen: arm: enable balloon driver
  xen: balloon: allow PVMMU interfaces to be compiled out
  xen: privcmd: support autotranslated physmap guests.
  xen: add pages parameter to xen_remap_domain_mfn_range
  xen/acpi: Move the xen_running_on_version_or_later function.
  xen/xenbus: Remove duplicate inclusion of asm/xen/hypervisor.h
  xen/acpi: Fix compile error by missing decleration for xen_domain.
  xen/acpi: revert pad config check in xen_check_mwait
  xen/acpi: ACPI PAD driver
  xen-pciback: reject out of range inputs
  xen-pciback: simplify and tighten parsing of device IDs
  xen PVonHVM: use E820_Reserved area for shared_info
2012-12-13 14:29:16 -08:00
Ian Campbell
f832da068b xen: arm: implement remap interfaces needed for privcmd mappings.
We use XENMEM_add_to_physmap_range which is the preferred interface
for foreign mappings.

Acked-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-29 14:00:19 +00:00
Ian Campbell
c61ba7291b xen: arm: enable balloon driver
The code is now in a state where can just enable it.

Drop the *_xenballloned_pages duplicates since these are now supplied
by the balloon code.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-29 12:59:14 +00:00
Stefano Stabellini
ab277bbf66 xen/arm: Fix compile errors when drivers are compiled as modules (export more).
The commit 911dec0db4
"xen/arm: Fix compile errors when drivers are compiled as modules." exports
the neccessary functions. But to guard ourselves against out-of-tree modules
and future drivers hitting this, lets export all of the relevant
hypercalls.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-09 07:48:22 -05:00
Konrad Rzeszutek Wilk
911dec0db4 xen/arm: Fix compile errors when drivers are compiled as modules.
We end up with:

ERROR: "HYPERVISOR_event_channel_op" [drivers/xen/xen-gntdev.ko] undefined!
ERROR: "privcmd_call" [drivers/xen/xen-privcmd.ko] undefined!
ERROR: "HYPERVISOR_grant_table_op" [drivers/net/xen-netback/xen-netback.ko] undefined!

and this patch exports said function (which is implemented in hypercall.S).

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-07 10:46:19 -05:00
Stefano Stabellini
c8d258a7b2 xen/arm: use the __HVC macro
Use the new __HVC macro in hypercall.S.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30 10:41:19 -04:00
Ian Campbell
ef32f89298 xen: grant: use xen_pfn_t type for frame_list.
This correctly sizes it as 64 bit on ARM but leaves it as unsigned
long on x86 (therefore no intended change on x86).

The long and ulong guest handles are now unused (and a bit dangerous)
so remove them.

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-19 15:17:55 -04:00
Stefano Stabellini
ea54209b16 xen/arm: implement alloc/free_xenballooned_pages with alloc_pages/kfree
Only until we get the balloon driver to work.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-08 17:20:58 +00:00
Stefano Stabellini
0ec53ecf38 xen/arm: receive Xen events on ARM
Compile events.c on ARM.
Parse, map and enable the IRQ to get event notifications from the device
tree (node "/xen").

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-14 13:37:32 +00:00
Stefano Stabellini
b3b52fd87e xen/arm: initialize grant_table on ARM
Initialize the grant table mapping at the address specified at index 0
in the DT under the /xen node.
After the grant table is initialized, call xenbus_probe (if not dom0).

Changes in v2:

- introduce GRANT_TABLE_PHYSADDR;
- remove unneeded initialization of boot_max_nr_grant_frames.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2012-09-13 12:06:52 +00:00
Stefano Stabellini
ef61ee0dc7 xen/arm: get privilege status
Use Xen features to figure out if we are privileged.

XENFEAT_dom0 was introduced by 23735 in xen-unstable.hg.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-08 17:20:18 +00:00
Stefano Stabellini
2e01f16601 xen/arm: Xen detection and shared_info page mapping
Check for a node in the device tree compatible with "xen,xen", if it is
present set xen_domain_type to XEN_HVM_DOMAIN and continue
initialization.

Map the real shared info page using XENMEM_add_to_physmap with
XENMAPSPACE_shared_info.

Changes in v4:

- simpler parsing of Xen version in the compatible DT node.

Changes in v3:

- use the "xen,xen" notation rather than "arm,xen";
- add an additional check on the presence of the Xen version.

Changes in v2:

- replace pr_info with pr_debug.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2012-09-14 10:47:52 +00:00
Stefano Stabellini
226f52e931 xen/arm: empty implementation of grant_table arch specific functions
Changes in v2:

- return -ENOSYS rather than -1.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-08 16:34:11 +00:00
Stefano Stabellini
aa2466d21b xen/arm: hypercalls
Use r12 to pass the hypercall number to the hypervisor.

We need a register to pass the hypercall number because we might not
know it at compile time and HVC only takes an immediate argument.

Among the available registers r12 seems to be the best choice because it
is defined as "intra-procedure call scratch register".

Use the ISS to pass an hypervisor specific tag.


Changes in v2:
- define an HYPERCALL macro for 5 arguments hypercall wrappers, even if
at the moment is unused;
- use ldm instead of pop;
- fix up comments.


Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-14 13:33:21 +00:00
Stefano Stabellini
4c071ee526 arm: initial Xen support
- Basic hypervisor.h and interface.h definitions.
- Skeleton enlighten.c, set xen_start_info to an empty struct.
- Make xen_initial_domain dependent on the SIF_PRIVILIGED_BIT.

The new code only compiles when CONFIG_XEN is set, that is going to be
added to arch/arm/Kconfig in patch #11 "xen/arm: introduce CONFIG_XEN on
ARM".

Changes in v3:

- improve comments.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-14 13:53:39 +00:00