* 'xen/xenbus' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xenbus: Fix memory leak on release
xenbus: avoid zero returns from read()
xenbus: add missing wakeup in concurrent read/write
xenbus: allow any xenbus command over /proc/xen/xenbus
xenfs/xenbus: report partial reads/writes correctly
* 'stable/gntdev' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/p2m: Fix module linking error.
xen p2m: clear the old pte when adding a page to m2p_override
xen gntdev: use gnttab_map_refs and gnttab_unmap_refs
xen: introduce gnttab_map_refs and gnttab_unmap_refs
xen p2m: transparently change the p2m mappings in the m2p override
xen/gntdev: Fix circular locking dependency
xen/gntdev: stop using "token" argument
xen: gntdev: move use of GNTMAP_contains_pte next to the map_op
xen: add m2p override mechanism
xen: move p2m handling to separate file
xen/gntdev: add VM_PFNMAP to vma
xen/gntdev: allow usermode to map granted pages
xen: define gnttab_set_map_op/unmap_op
Fix up trivial conflict in drivers/xen/Kconfig
* 'stable/platform-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen-platform: Fix compile errors if CONFIG_PCI is not enabled.
xen: rename platform-pci module to xen-platform-pci.
xen-platform: use PCI interfaces to request IO and MEM resources.
drivers/xen/platform-pci.c:127: error: implicit declaration of function
'pci_request_region'
drivers/xen/platform-pci.c:165: error: implicit declaration of function
'pci_release_region'
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'stable/xenbus' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/xenbus: making backend support modular is too complex
xen/pci: Make xen-pcifront be dependent on XEN_XENBUS_FRONTEND
xen/xenbus: fixup checkpatch issues in xenbus_probe*
xen/netfront: select XEN_XENBUS_FRONTEND
xen/xenbus: clean up noise in xenbus_probe_frontend.c
xen/xenbus: clean up noise in xenbus_probe_backend.c
xen/xenbus: clean up noise in xenbus_probe.c
xen/xenbus: cleanup debug noise in xenbus_comms.c
xen/xenbus: clean up error handling
xen/xenbus: make frontend bus GPL
xen/xenbus: make sure backend bus is registered earlier
xenbus/frontend: register bus earlier
xen: remove xen/evtchn.h
xen: add backend driver support
xen: separate out frontend xenbus
platform-pci is rather generic for a modular distro style kernel.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This is the correct interface to use and something has broken the use
of the previous incorrect interface (which fails because the request
conflicts with the resources assigned for the PCI device itself
instead of nesting like the PCI interfaces do).
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: stable@kernel.org # 2.6.37 only
When adding a page to m2p_override we change the p2m of the page so we
need to also clear the old pte of the kernel linear mapping because it
doesn't correspond anymore.
When we remove the page from m2p_override we restore the original p2m of
the page and we also restore the old pte of the kernel linear mapping.
Before changing the p2m mappings in m2p_add_override and
m2p_remove_override, check that the page passed as argument is valid and
return an error if it is not.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Use gnttab_map_refs and gnttab_unmap_refs to map and unmap the grant
ref, so that we can have a corresponding struct page.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
gnttab_map_refs maps some grant refs and uses the new m2p override to
set a proper m2p mapping for the granted pages.
gnttab_unmap_refs unmaps the granted refs and removes th mappings from
the m2p override.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
apply_to_page_range will acquire PTE lock while priv->lock is held,
and mn_invl_range_start tries to acquire priv->lock with PTE already
held. Fix by not holding priv->lock during the entire map operation.
This is safe because map->vma is set nonzero while the lock is held,
which will cause subsequent maps to fail and will cause the unmap
ioctl (and other users of gntdev_del_map) to return -EBUSY until the
area is unmapped. It is similarly impossible for gntdev_vma_close to
be called while the vma is still being created.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
It's the struct page of the L1 pte page. But we can get its mfn
by simply doing an arbitrary_virt_to_machine() on it anyway (which is
the safe conservative choice; since we no longer allow HIGHPTE pages,
we would never expect to be operating on a mapped pte page).
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This flag controls the meaning of gnttab_map_grant_ref.host_addr and
specifies that the field contains a reference to the pte entry to be
used to perform the mapping. Therefore move the use of this flag to
the point at which we actually use a reference to the pte instead of
something else, splitting up the usage of the flag in this way is
confusing and potentially error prone.
The other flags are all properties of the mapping itself as opposed to
properties of the hypercall arguments and therefore it make sense to
continue to pass them round in map->flags.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
Cc: Derek G. Murray <Derek.Murray@cl.cam.ac.uk>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
These pages are from other domains, so don't have any local PFN.
VM_PFNMAP is the closest concept Linux has to this.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The gntdev driver allows usermode to map granted pages from other
domains. This is typically used to implement a Xen backend driver
in user mode.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* 'stable/bug-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/event: validate irq before get evtchn by irq
xen/fb: fix potential memory leak
xen/fb: fix xenfb suspend/resume race.
xen: disable ACPI NUMA for PV guests
xen/irq: Cleanup the find_unbound_irq
When retrieving the event channel number from irq, the irq
number may not be valid under some conditions.
So far that can be when we suspend/resume and irq ends with -1.
Validate and return sanitized irq and provide diagnostics information.
[v3: added unlikely on the WARN path]
[v2: reworded the commit message]
Signed-off-by: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Gurudas Pai <gurudas.pai@oracle.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Impact: build fix
Making the xenbus backend support a separate module is needlessly complex
and causes build failures.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 616ff7a06a3f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 98b833aaf81e in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 01aded30aaef in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 6796c12281dc in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Don't report errors when booting on non-Xen, because its just confusing.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 8aa08376d6aa in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Make sure frontend xenbus has a GPL module license, so it can access
all the xenbus symbols exported GPL only.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 525cbc8adcb5 in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: bugfix
Need to register it before any drivers want to attach.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to a7a9c3a942c6 in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: bugfix
Make sure the frontend bus is registered early, before
any drivers want to attach.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to 1d5df318f87f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: cleanup
It's a usermode header for users of /dev/xen/evtchn.
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[corresponds to b60e48cec12f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: backend device support
Add the basic machinery to support backend drivers.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[corresponds to 79727b851bac in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: refactor
Make a distinct frontend xenbus, in preparation for adding a backend xenbus.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[corresponds to 2fd433a4188f in git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git
with adjustments to reflect changes in the code which is moved]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Pending responses were leaked on close.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
__this_cpu_inc_return reduces code and simplifies code.
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Use this_cpu_ops to reduce code size and simplify things in various places.
V3->V4:
Move instance of this_cpu_inc_return to a later patchset so that
this patch can be applied without infrastructure changes.
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The "find_unbound_irq" is a bit unusual - it allocates
virtual IRQ (event channels) in reverse order. This means
starting at the "top" of the available IRQs (nr_irqs) down
to the GSI/MSI IRQs (nr_irqs_gsi). Lets document this and
also make the variables easier to understand.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* '2.6.37-rc4-pvhvm-fixes' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
xen: unplug the emulated devices at resume time
xen: fix save/restore for PV on HVM guests with pirq remapping
xen: resume the pv console for hvm guests too
xen: fix MSI setup and teardown for PV on HVM guests
xen: use PHYSDEVOP_get_free_pirq to implement find_unbound_pirq
* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: allocate irq descs on any NUMA node
xen: prevent crashes with non-HIGHMEM 32-bit kernels with largeish memory
xen: use default_idle
xen: clean up "extra" memory handling some more
* 'upstream/bugfix' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: x86/32: perform initial startup on initial_page_table
xen: don't bother to stop other cpus on shutdown/reboot
Allocate irq descs on any NUMA node (we don't care) rather than
specifically node 0, which may not exist.
(At the moment NUMA is meaningless within a domain, so any info
the kernel has is just from an SRAT table we haven't suppressed/disabled.)
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
If this is a non-HIGHMEM 32-bit kernel, then the page structures only go
up to the limit of addressable memory, even if more memory is physically
present. Don't try to add that extra memory to the balloon.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
When remapping MSIs into pirqs for PV on HVM guests, qemu is responsible
for doing the actual mapping and unmapping.
We only give qemu the desired pirq number when we ask to do the mapping
the first time, after that we should be reading back the pirq number
from qemu every time we want to re-enable the MSI.
This fixes a bug in xen_hvm_setup_msi_irqs that manifests itself when
trying to enable the same MSI for the second time: the old MSI to pirq
mapping is still valid at this point but xen_hvm_setup_msi_irqs would
try to assign a new pirq anyway.
A simple way to reproduce this bug is to assign an MSI capable network
card to a PV on HVM guest, if the user brings down the corresponding
ethernet interface and up again, Linux would fail to enable MSIs on the
device.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Use the new hypercall PHYSDEVOP_get_free_pirq to ask Xen to allocate a
pirq. Remove the unsupported PHYSDEVOP_get_nr_pirqs hypercall to get the
amount of pirq available.
This fixes find_unbound_pirq that otherwise would return a number
starting from nr_irqs that might very well be out of range in Xen.
The symptom of this bug is that when you passthrough an MSI capable pci
device to a PV on HVM guest, Linux would fail to enable MSIs on the
device.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
* 'upstream/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: (23 commits)
xen/events: Use PIRQ instead of GSI value when unmapping MSI/MSI-X irqs.
xen: set IO permission early (before early_cpu_init())
xen: re-enable boot-time ballooning
xen/balloon: make sure we only include remaining extra ram
xen/balloon: the balloon_lock is useless
xen: add extra pages to balloon
xen: make evtchn's name less generic
xen/evtchn: the evtchn device is non-seekable
Revert "xen/privcmd: create address space to allow writable mmaps"
xen/events: use locked set|clear_bit() for cpu_evtchn_mask
xen/evtchn: clear secondary CPUs' cpu_evtchn_mask[] after restore
xen/xenfs: update xenfs_mount for new prototype
xen: fix header export to userspace
xen: implement XENMEM_machphys_mapping
xen: set vma flag VM_PFNMAP in the privcmd mmap file_op
xen: xenfs: privcmd: check put_user() return code
xen/evtchn: add missing static
xen/evtchn: Fix name of Xen event-channel device
xen/evtchn: don't do unbind_from_irqhandler under spinlock
xen/evtchn: remove spurious barrier
...
* upstream/core:
xen/events: Use PIRQ instead of GSI value when unmapping MSI/MSI-X irqs.
xen: set IO permission early (before early_cpu_init())
xen: re-enable boot-time ballooning
xen/balloon: make sure we only include remaining extra ram
xen/balloon: the balloon_lock is useless
xen: add extra pages to balloon
xen/events: use locked set|clear_bit() for cpu_evtchn_mask
xen/evtchn: clear secondary CPUs' cpu_evtchn_mask[] after restore
xen: implement XENMEM_machphys_mapping
* upstream/xenfs:
Revert "xen/privcmd: create address space to allow writable mmaps"
xen/xenfs: update xenfs_mount for new prototype
xen: fix header export to userspace
xen: set vma flag VM_PFNMAP in the privcmd mmap file_op
xen: xenfs: privcmd: check put_user() return code
* upstream/evtchn:
xen: make evtchn's name less generic
xen/evtchn: the evtchn device is non-seekable
xen/evtchn: add missing static
xen/evtchn: Fix name of Xen event-channel device
xen/evtchn: don't do unbind_from_irqhandler under spinlock
xen/evtchn: remove spurious barrier
xen/evtchn: ports start enabled
xen/evtchn: dynamically allocate port_user array
xen/evtchn: track enabled state for each port
When we allocate a vector for MSI/MSI-X we save away the PIRQ, and the
vector value. When we unmap (de-allocate) the MSI/MSI-X vector(s) we
need to provide the PIRQ and the vector value. What we did instead
was to provide the GSI (which was zero) and the vector value, and we
got these unhappy error messages:
(XEN) irq.c:1575: dom0: pirq 0 not mapped
[ 7.733415] unmap irq failed -22
This patches fixes this and we use the PIRQ value instead of the GSI
value.
CC: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If the user specifies mem= on the kernel command line, some or all
of the extra memory E820 region may be clipped away, so make sure
we don't try to add more extra memory than exists in E820.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Add extra pages in the pseudo-physical address space to the balloon
so we can extend into them later.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* xen/dev-evtchn:
xen/evtchn: add missing static
xen/evtchn: Fix name of Xen event-channel device
xen/evtchn: don't do unbind_from_irqhandler under spinlock
xen/evtchn: remove spurious barrier
xen/evtchn: ports start enabled
xen/evtchn: dynamically allocate port_user array
xen/evtchn: track enabled state for each port
This reverts commit 24a89b5be4.
We should no longer need an address space now that we're correctly
setting VM_PFNMAP on our vmas.
Conflicts:
drivers/xen/xenfs/super.c
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The per-cpu event channel masks can be updated unlocked from multiple
CPUs, so use the locked variant.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
To bind all event channels to CPU#0, it is not sufficient to set all
of its cpu_evtchn_mask[] bits; all other CPUs also need to get their
bits cleared. Otherwise, evtchn_do_upcall() will start handling
interrupts on CPUs they're not intended to run on, which can be
particularly bad for per-CPU ones.
[ linux-2.6.18-xen.hg 7de7453dee36 ]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* commit 'v2.6.37-rc2': (10093 commits)
Linux 2.6.37-rc2
capabilities/syslog: open code cap_syslog logic to fix build failure
i2c: Sanity checks on adapter registration
i2c: Mark i2c_adapter.id as deprecated
i2c: Drivers shouldn't include <linux/i2c-id.h>
i2c: Delete unused adapter IDs
i2c: Remove obsolete cleanup for clientdata
include/linux/kernel.h: Move logging bits to include/linux/printk.h
Fix gcc 4.5.1 miscompiling drivers/char/i8k.c (again)
hwmon: (w83795) Check for BEEP pin availability
hwmon: (w83795) Clear intrusion alarm immediately
hwmon: (w83795) Read the intrusion state properly
hwmon: (w83795) Print the actual temperature channels as sources
hwmon: (w83795) List all usable temperature sources
hwmon: (w83795) Expose fan control method
hwmon: (w83795) Fix fan control mode attributes
hwmon: (lm95241) Check validity of input values
hwmon: Change mail address of Hans J. Koch
PCI: sysfs: fix printk warnings
GFS2: Fix inode deallocation race
...
* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen: do not release any memory under 1M in domain 0
xen: events: do not unmask event channels on resume
xen: correct size of level2_kernel_pgt
Set VM_PFNMAP in the privcmd mmap file_op, rather than later in
xen_remap_domain_mfn_range when it is too late because
vma_wants_writenotify has already been called and vm_page_prot has
already been modified.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
put_user() may fail. In this case propagate error code from
privcmd_ioctl_mmap_batch().
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
and branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm
* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
xen: register xen pci notifier
xen: initialize cpu masks for pv guests in xen_smp_init
xen: add a missing #include to arch/x86/pci/xen.c
xen: mask the MTRR feature from the cpuid
xen: make hvc_xen console work for dom0.
xen: add the direct mapping area for ISA bus access
xen: Initialize xenbus for dom0.
xen: use vcpu_ops to setup cpu masks
xen: map a dummy page for local apic and ioapic in xen_set_fixmap
xen: remap MSIs into pirqs when running as initial domain
xen: remap GSIs as pirqs when running as initial domain
xen: introduce XEN_DOM0 as a silent option
xen: map MSIs into pirqs
xen: support GSI -> pirq remapping in PV on HVM guests
xen: add xen hvm acpi_register_gsi variant
acpi: use indirect call to register gsi in different modes
xen: implement xen_hvm_register_pirq
xen: get the maximum number of pirqs from xen
xen: support pirq != irq
* 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (27 commits)
X86/PCI: Remove the dependency on isapnp_disable.
xen: Update Makefile with CONFIG_BLOCK dependency for biomerge.c
MAINTAINERS: Add myself to the Xen Hypervisor Interface and remove Chris Wright.
x86: xen: Sanitse irq handling (part two)
swiotlb-xen: On x86-32 builts, select SWIOTLB instead of depending on it.
MAINTAINERS: Add myself for Xen PCI and Xen SWIOTLB maintainer.
xen/pci: Request ACS when Xen-SWIOTLB is activated.
xen-pcifront: Xen PCI frontend driver.
xenbus: prevent warnings on unhandled enumeration values
xenbus: Xen paravirtualised PCI hotplug support.
xen/x86/PCI: Add support for the Xen PCI subsystem
x86: Introduce x86_msi_ops
msi: Introduce default_[teardown|setup]_msi_irqs with fallback.
x86/PCI: Export pci_walk_bus function.
x86/PCI: make sure _PAGE_IOMAP it set on pci mappings
x86/PCI: Clean up pci_cache_line_size
xen: fix shared irq device passthrough
xen: Provide a variant of xen_poll_irq with timeout.
xen: Find an unbound irq number in reverse order (high to low).
xen: statically initialize cpu_evtchn_mask_p
...
Fix up trivial conflicts in drivers/pci/Makefile
Register a pci notifier to add (or remove) pci devices to Xen via
hypercalls. Xen needs to know the pci devices present in the system to
handle pci passthrough and even MSI remapping in the initial domain.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
* 'upstream/xenfs' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen/privcmd: make privcmd visible in domU
xen/privcmd: move remap_domain_mfn_range() to core xen code and export.
privcmd: MMAPBATCH: Fix error handling/reporting
xenbus: export xen_store_interface for xenfs
xen/privcmd: make sure vma is ours before doing anything to it
xen/privcmd: print SIGBUS faults
xen/xenfs: set_page_dirty is supposed to return true if it dirties
xen/privcmd: create address space to allow writable mmaps
xen: add privcmd driver
xen: add variable hypercall caller
xen: add xen_set_domain_pte()
xen: add /proc/xen/xsd_{kva,port} to xenfs
* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: (29 commits)
xen: include xen/xen.h for definition of xen_initial_domain()
xen: use host E820 map for dom0
xen: correctly rebuild mfn list list after migration.
xen: improvements to VIRQ_DEBUG output
xen: set up IRQ before binding virq to evtchn
xen: ensure that all event channels start off bound to VCPU 0
xen/hvc: only notify if we actually sent something
xen: don't add extra_pages for RAM after mem_end
xen: add support for PAT
xen: make sure xen_max_p2m_pfn is up to date
xen: limit extra memory to a certain ratio of base
xen: add extra pages for E820 RAM regions, even if beyond mem_end
xen: make sure xen_extra_mem_start is beyond all non-RAM e820
xen: implement "extra" memory to reserve space for pages not present at boot
xen: Use host-provided E820 map
xen: don't map missing memory
xen: defer building p2m mfn structures until kernel is mapped
xen: add return value to set_phys_to_machine()
xen: convert p2m to a 3 level tree
xen: make install_p2mtop_page() static
...
Fix up trivial conflict in arch/x86/xen/mmu.c, and fix the use of
'reserve_early()' - in the new memblock world order it is now
'memblock_x86_reserve_range()' instead. Pointed out by Jeremy.
Do initial xenbus/xenstore setup in dom0. In dom0 we need to actually
allocate the xenstore resources, rather than being given them from
outside.
[ Impact: initialize Xenbus ]
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Implement xen_create_msi_irq to create an msi and remap it as pirq.
Use xen_create_msi_irq to implement an initial domain specific version
of setup_msi_irqs.
Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Implement xen_register_gsi to setup the correct triggering and polarity
properties of a gsi.
Implement xen_register_pirq to register a particular gsi as pirq and
receive interrupts as events.
Call xen_setup_pirqs to register all the legacy ISA irqs as pirqs.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Map MSIs into pirqs, writing 0 in the MSI vector data field and the pirq
number in the MSI destination id field.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Disable pcifront when running on HVM: it is meant to be used with pv
guests that don't have PCI bus.
Use acpi_register_gsi_xen_hvm to remap GSIs into pirqs.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen_hvm_register_pirq allows the kernel to map a GSI into a Xen pirq and
receive the interrupt as an event channel from that point on.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Use PHYSDEVOP_get_nr_pirqs to get the maximum number of pirqs from xen.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
PHYSDEVOP_map_pirq might return a pirq different from what we asked if
we are running as an HVM guest, so we need to be able to support pirqs
that are different from linux irqs.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* Fix bitmask formatting on 64 bit by specifying correct field widths.
* Output both global and local masked and pending information.
* Indicate in list of pending interrupts whether they are pending in
the L2, masked globally and/or masked locally.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
All event channels startbound to VCPU 0 so ensure that cpu_evtchn_mask
is initialised to reflect this. Otherwise there is a race after registering an
event channel but before the affinity is explicitly set where the event channel
can be delivered. If this happens then the event channel remains pending in the
L1 (evtchn_pending) array but is cleared in L2 (evtchn_pending_sel), this means
the event channel cannot be reraised until another event channel happens to
trigger the same L2 entry on that VCPU.
sizeof(cpu_evtchn_mask(0))==sizeof(unsigned long*) which is not correct, and
causes only the first 32 or 64 event channels (depending on architecture) to be
initially bound to VCPU0. Use sizeof(struct cpu_evtchn_s) instead.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: stable@kernel.org
Change event delivery to:
- mask+clear event in the upcall function
- use handle_fasteoi_irq as the handler
- unmask in the eoi function (and handle migration)
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
It has its uses in a domU as well as dom0. Xen will prevent an
unprivileged domain from doing anything untoward.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
This allows xenfs to be built as a module, previously it required flush_tlb_all
and arbitrary_virt_to_machine to be exported.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
On error IOCTL_PRIVCMD_MMAPBATCH is expected to set the top nibble of
the effected MFN and return 0. Currently it leaves the MFN unmodified
and returns the number of failures. Therefore:
- reimplement remap_domain_mfn_range() using direct
HYPERVISOR_mmu_update() calls and small batches. The xen_set_domain_pte()
interface does not report errors and since some failures are
expected/normal using the multicall infrastructure is too noisy.
- return 0 as expected
- writeback the updated MFN list to mmapbatch->arr not over mmapbatch,
smashing the caller's stack.
- remap_domain_mfn_range can be static.
With this change I am able to start an HVM domain.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
xen_store_interface is needed by xenfs, and xenfs may be a module.
[ Impact: build fix for modular xenfs ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Test vma->vm_ops is our operations to make sure we created it.
We don't want to stomp on other random vmas.
[ Impact: bugfix; prevent ioctl from affecting other mappings ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
I don't think it matters at all in this case (there's only one caller
which checks the return value), but may as well be strictly correct.
[ Impact: cleanup ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
These are necessary to allow writeable mmap of the privcmd node to
succeed without being marked read-only for writenotify purposes. Which
in turn is necessary to allow mappings of foreign guest pages
[ Impact: bugfix: allow writable mappings ]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
The privcmd interface in xenfs allows the tool stack in the privileged
domain to get fairly direct access to the hypervisor in order to do
various management things such as domain construction.
[ Impact: new xenfs interface for privileged operations ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
These are used by the userspace xenstore daemon, which runs in dom0.
Xenstored is what's behind the xenfs "xenbus" filesystem.
[ Impact: provide mapping and port to usermode for xenstore ]
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Without this dependency we get these compile errors:
linux-next-20101020/drivers/xen/biomerge.c: In function 'xen_biovec_phys_mergeable':
linux-next-20101020/drivers/xen/biomerge.c:8: error: dereferencing pointer to incomplete type
linux-next-20101020/drivers/xen/biomerge.c:9: error: dereferencing pointer to incomplete type
linux-next-20101020/drivers/xen/biomerge.c:11: error: implicit declaration of function '__BIOVEC_PHYS_MERGEABLE'
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Thomas Gleixner cleaned up event handling to use the
sparse_irq handling, but the xen-pcifront patches utilized the
old mechanism. This fixes them to work with sparse_irq handling.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We used to depend on CONFIG_SWIOTLB, but that is disabled by default.
So when compiling we get this compile error:
arch/x86/xen/pci-swiotlb-xen.c: In function 'pci_xen_swiotlb_detect':
arch/x86/xen/pci-swiotlb-xen.c:48: error: lvalue required as left operand of assignment
Fix it by actually activating the SWIOTLB library.
Reported-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
It used to done in the Xen startup code but that is not really
appropiate.
[v2: Update Kconfig with PCI requirement]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The Xen PCI front driver adds two new states that are utilizez
for PCI hotplug support. This is a patch pulled from the
linux-2.6-xen-sparse tree.
Signed-off-by: Noboru Iwamatsu <n_iwamatsu@jp.fujitsu.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Yosuke Iwamatsu <y-iwamatsu@ab.jp.nec.com>
The frontend stub lives in arch/x86/pci/xen.c, alongside other
sub-arch PCI init code (e.g. olpc.c).
It provides a mechanism for Xen PCI frontend to setup/destroy
legacy interrupts, MSI/MSI-X, and PCI configuration operations.
[ Impact: add core of Xen PCI support ]
[ v2: Removed the IOMMU code and only focusing on PCI.]
[ v3: removed usage of pci_scan_all_fns as that does not exist]
[ v4: introduced pci_xen value to fix compile warnings]
[ v5: squished fixes+features in one patch, changed Reviewed-by to Ccs]
[ v7: added Acked-by]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Qing He <qing.he@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
In driver/xen/events.c, whether bind_pirq is shareable or not is
determined by desc->action is NULL or not. But in __setup_irq,
startup(irq) is invoked before desc->action is assigned with
new action. So desc->action in startup_irq is always NULL, and
bind_pirq is always not shareable. This results in pt_irq_create_bind
failure when passthrough a device which shares irq to other devices.
This patch doesn't use probing_irq to determine if pirq is shareable
or not, instead set shareable flag in irq_info according to trigger
mode in xen_allocate_pirq. Set level triggered interrupts shareable.
Thus use this flag to set bind_pirq flag accordingly.
[v2: arch/x86/xen/pci.c no more, so file skipped]
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The 'xen_poll_irq_timeout' provides a method to pass in
the poll timeout for IRQs if requested. We also export
those two poll functions as Xen PCI fronted uses them.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
In earlier Xen Linux kernels, the IRQ mapping was a straight 1:1 and the
find_unbound_irq started looking around 256 for open IRQs and up. IRQs
from 0 to 255 were reserved for PCI devices. Previous to this patch,
the 'find_unbound_irq' started looking at get_nr_hw_irqs() number.
For privileged domain where the ACPI information is available that
returns the upper-bound of what the GSIs. For non-privileged PV domains,
where ACPI is no-existent the get_nr_hw_irqs() reports the IRQ_LEGACY (16).
With PCI passthrough enabled, and with PCI cards that have IRQs pinned
to a higher number than 16 we collide with previously allocated IRQs.
Specifically the PCI IRQs collide with the IPI's for Xen functions
(as they are allocated earlier).
For example:
00:00.11 USB Controller: ATI Technologies Inc SB700 USB OHCI1 Controller (prog-if 10 [OHCI])
...
Interrupt: pin A routed to IRQ 18
[root@localhost ~]# cat /proc/interrupts | head
CPU0 CPU1 CPU2
16: 38186 0 0 xen-dyn-virq timer0
17: 149 0 0 xen-dyn-ipi spinlock0
18: 962 0 0 xen-dyn-ipi resched0
and when the USB controller is loaded, the kernel reports:
IRQ handler type mismatch for IRQ 18
current handler: resched0
One way to fix this is to reverse the logic when looking for un-used
IRQ numbers and start with the highest available number. With that,
we would get:
CPU0 CPU1 CPU2
... snip ..
292: 35 0 0 xen-dyn-ipi callfunc0
293: 3992 0 0 xen-dyn-ipi resched0
294: 224 0 0 xen-dyn-ipi spinlock0
295: 57183 0 0 xen-dyn-virq timer0
NMI: 0 0 0 Non-maskable interrupts
.. snip ..
And interrupts for PCI cards are now accessible.
This patch also includes the fix, found by Ian Campbell, titled
"xen: fix off-by-one error in find_unbound_irq."
[v2: Added an explanation in the code]
[v3: Rebased on top of tip/irq/core]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Sometimes cpu_evtchn_mask_p can get used early, before it has been
allocated. Statically initialize it with an initdata version to catch
any early references.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: cleanup
Make pirq show useful information in /proc/interrupts
[v2: Removed the parts for arch/x86/xen/pci.c ]
Signed-off-by: Gerd Hoffmann <kraxel@xeni.home.kraxel.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Dynamically allocate the irq_info and evtchn_to_irq arrays, so that
1) the irq_info array scales to the actual number of possible irqs,
and 2) we don't needlessly increase the static size of the kernel
when we aren't running under Xen.
Derived on patch from Mike Travis <travis@sgi.com>.
[Impact: reduce memory usage ]
[v2: Conflict in drivers/xen/events.c: Replaced alloc_bootmen with kcalloc ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: preserve compat with native
Reserve the lower irq range for use for hardware interrupts so we
can identity-map them.
[v2: Rebased on top tip/irq/core]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
A privileged PV Xen domain can get direct access to hardware. In
order for this to be useful, it must be able to get hardware
interrupts.
Being a PV Xen domain, all interrupts are delivered as event channels.
PIRQ event channels are bound to a pirq number and an interrupt
vector. When a IO APIC raises a hardware interrupt on that vector, it
is delivered as an event channel, which we can deliver to the
appropriate device driver(s).
This patch simply implements the infrastructure for dealing with pirq
event channels.
[ Impact: integrate hardware interrupts into Xen's event scheme ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Impact: allow Xen control of bio merging
When running in Xen domain with device access, we need to make sure
the block subsystem doesn't merge requests across pages which aren't
machine physically contiguous. To do this, we define our own
BIOVEC_PHYS_MERGEABLE. When CONFIG_XEN isn't enabled, or we're not
running in a Xen domain, this has identical behaviour to the normal
implementation. When running under Xen, we also make sure the
underlying machine pages are the same or adjacent.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
There seems to be more cleanups possible, but that's left to the xen
experts :)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Register_xenstore_notifier should guarantee that the caller gets
notified even if xenstore is already up.
Therefore we revert "do not notify callers from
register_xenstore_notifier" and set xenstored_read at the right time for
PV on HVM guests too.
In fact in case of PV on HVM guests xenstored is ready only after the
platform pci driver has completed the initialization, so do not set
xenstored_ready before the call to xenbus_probe().
This patch fixes a shutdown_event watcher registration bug that causes
"xm shutdown" not to work properly.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
It is possible to get a zero return from read() in instances where the
queue is not empty but has no elements with data to deliver to the user.
Since a zero return from read is an error indicator, resume waiting or
return -EAGAIN (for a nonblocking fd) in this case.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
If an application has a dedicated read thread watching xenbus and
another thread writes an XS_WATCH message that generates a synthetic
"OK" reply, this reply will be enqueued in the buffer without waking up
the reader. This can cause a deadlock in the application if it then
waits for the read thread to receive the queued message.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
commit e752969f502a511e83f841aa01d6cd332e6d85a0
Author: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Date: Tue Sep 7 11:21:52 2010 -0400
xenbus: fix deadlock in concurrent read/write
If an application has a dedicated read thread watching xenbus and another
thread writes an XS_WATCH message that generates a synthetic "OK" reply,
this reply will be enqueued in the buffer without waking up the reader.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
When xenstored is in another domain, we need to be able to send any
command over xenbus. This doesn't pose a security problem because
its up to xenstored to determine whether a given client is allowed
to use a particular command anyway.
From linux-2.5.18-xen.hg 68d582b0ad05.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
copy_(to|from)_user return the number of uncopied bytes, so a successful
return is 0, and any non-zero result indicates some degree of failure.
Reported-by: "Jun Zhu (Intern)" <Jun.Zhu@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Xen events are logically edge triggered, as Xen only calls the event
upcall when an event is newly set, but not continuously as it remains set.
As a result, use handle_edge_irq rather than handle_level_irq.
This has the important side-effect of fixing a long-standing bug of
events getting lost if:
- an event's interrupt handler is running
- the event is migrated to a different vcpu
- the event is re-triggered
The most noticable symptom of these lost events is occasional lockups
of blkfront.
Many thanks to Tom Kopec and Daniel Stodden in tracking this down.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Tom Kopec <tek@acm.org>
Cc: Daniel Stodden <daniel.stodden@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
IPIs and VIRQs are inherently per-cpu event types, so treat them as such:
- use a specific percpu irq_chip implementation, and
- handle them with handle_percpu_irq
This makes the path for delivering these interrupts more efficient
(no masking/unmasking, no locks), and it avoid problems with attempts
to migrate them.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
Sysrq operations do not accept tty argument anymore so no need to pass
it to us.
[Stephen Rothwell <sfr@canb.auug.org.au>: fix build breakage in drm code
caused by sysrq using bool but not including linux/types.h]
[Sachin Sant <sachinp@in.ibm.com>: fix build breakage in s390 keyboadr
driver]
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
* 'stable/xen-swiotlb-0.8.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
x86: Detect whether we should use Xen SWIOTLB.
pci-swiotlb-xen: Add glue code to setup dma_ops utilizing xen_swiotlb_* functions.
swiotlb-xen: SWIOTLB library for Xen PV guest with PCI passthrough.
xen/mmu: inhibit vmap aliases rather than trying to clear them out
vmap: add flag to allow lazy unmap to be disabled at runtime
xen: Add xen_create_contiguous_region
xen: Rename the balloon lock
xen: Allow unprivileged Xen domains to create iomap pages
xen: use _PAGE_IOMAP in ioremap to do machine mappings
Fix up trivial conflicts (adding both xen swiotlb and xen pci platform
driver setup close to each other) in drivers/xen/{Kconfig,Makefile} and
include/xen/xen-ops.h
* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
xen-blkfront: fix missing out label
blkdev: fix blkdev_issue_zeroout return value
block: update request stacking methods to support discards
block: fix missing export of blk_types.h
writeback: fix bad _bh spinlock nesting
drbd: revert "delay probes", feature is being re-implemented differently
drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
drbd: Disable delay probes for the upcomming release
writeback: cleanup bdi_register
writeback: add new tracepoints
writeback: remove unnecessary init_timer call
writeback: optimize periodic bdi thread wakeups
writeback: prevent unnecessary bdi threads wakeups
writeback: move bdi threads exiting logic to the forker thread
writeback: restructure bdi forker loop a little
writeback: move last_active to bdi
writeback: do not remove bdi from bdi_list
writeback: simplify bdi code a little
writeback: do not lose wake-ups in bdi threads
...
Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.
According to the comments, this was how it's been done years ago, but
apparently took an xbt pointer from elsewhere back then. The code was
removed because of consistency issues: cancellation wont't roll back
the saved xbdev->state.
Still, unsolicited writes to the state field remain an issue,
especially if device shutdown takes thread synchronization, and subtle
races cause accidental recreation of the device node.
Fixed by reintroducing the transaction. An internal one is sufficient,
so the xbdev->state value remains consistent.
Also fixes the original hack to prevent infinite recursion. Instead of
bailing out on the first attempt to switch to Closing, checks call
depth now.
Signed-off-by: Daniel Stodden <daniel.stodden@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
xen: Do not suspend IPI IRQs.
powerpc: Use IRQF_NO_SUSPEND not IRQF_TIMER for non-timer interrupts
ixp4xx-beeper: Use IRQF_NO_SUSPEND not IRQF_TIMER for non-timer interrupt
irq: Add new IRQ flag IRQF_NO_SUSPEND
* upstream/pvhvm:
Introduce CONFIG_XEN_PVHVM compile option
blkfront: do not create a PV cdrom device if xen_hvm_guest
support multiple .discard.* sections to avoid section type conflicts
xen/pvhvm: fix build problem when !CONFIG_XEN
xenfs: enable for HVM domains too
x86: Call HVMOP_pagetable_dying on exit_mmap.
x86: Unplug emulated disks and nics.
x86: Use xen_vcpuop_clockevent, xen_clocksource and xen wallclock.
xen: Fix find_unbound_irq in presence of ioapic irqs.
xen: Add suspend/resume support for PV on HVM guests.
xen: Xen PCI platform device driver.
x86/xen: event channels delivery on HVM.
x86: early PV on HVM features initialization.
xen: Add support for HVM hypercalls.
Conflicts:
arch/x86/xen/enlighten.c
arch/x86/xen/time.c
* upstream/core:
xen/panic: use xen_reboot and fix smp_send_stop
Xen: register panic notifier to take crashes of xen guests on panic
xen: support large numbers of CPUs with vcpu info placement
xen: drop xen_sched_clock in favour of using plain wallclock time
pvops: do not notify callers from register_xenstore_notifier
xen: make sure pages are really part of domain before freeing
xen: release unused free memory
Currently register_xenstore_notifier notifies the caller during the
registration itself if xenstore is believed to be ready. This behaviour
causes problems to PV on HVM guests, in which case callers should be
notified by xenbus_probe only after the platform pci driver is loaded.
We already make sure xenbus_probe is called at the right time, calling
it either from device_initcall (PV case) or from the platform pci
driver initialization (HVM case) so we don't need this additional
notification.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
This patch introduce a CONFIG_XEN_PVHVM compile time option to
enable/disable Xen PV on HVM support.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
In general the semantics of IPIs are that they are are expected to
continue functioning after dpm_suspend_noirq().
Specifically I have seen a deadlock between the callfunc IPI and the
stop machine used by xen's do_suspend() routine. If one CPU has already
called dpm_suspend_noirq() then there is a window where it can be sent
a callfunc IPI before all the other CPUs have entered stop_cpu().
If this happens then the first CPU ends up spinning in stop_cpu()
waiting for the other to rendezvous in state STOPMACHINE_PREPARE while
the other is spinning in csd_lock_wait().
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: xen-devel@lists.xensource.com
LKML-Reference: <1280398595-29708-4-git-send-email-ian.campbell@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patchset:
PV guests under Xen are running in an non-contiguous memory architecture.
When PCI pass-through is utilized, this necessitates an IOMMU for
translating bus (DMA) to virtual and vice-versa and also providing a
mechanism to have contiguous pages for device drivers operations (say DMA
operations).
Specifically, under Xen the Linux idea of pages is an illusion. It
assumes that pages start at zero and go up to the available memory. To
help with that, the Linux Xen MMU provides a lookup mechanism to
translate the page frame numbers (PFN) to machine frame numbers (MFN)
and vice-versa. The MFN are the "real" frame numbers. Furthermore
memory is not contiguous. Xen hypervisor stitches memory for guests
from different pools, which means there is no guarantee that PFN==MFN
and PFN+1==MFN+1. Lastly with Xen 4.0, pages (in debug mode) are
allocated in descending order (high to low), meaning the guest might
never get any MFN's under the 4GB mark.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Albert Herranz <albert_herranz@yahoo.es>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Add a xen_emul_unplug command line option to the kernel to unplug
xen emulated disks and nics.
Set the default value of xen_emul_unplug depending on whether or
not the Xen PV frontends and the Xen platform PCI driver have
been compiled for this kernel (modules or built-in are both OK).
The user can specify xen_emul_unplug=ignore to enable PV drivers on HVM
even if the host platform doesn't support unplug.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
This patch implements O_NONBLOCK for /proc/xen/xenbus. It is a simple
matter of returning -EAGAIN instead of waiting on a queue.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Don't break the assumption that the first 16 irqs are ISA irqs;
make sure that the irq is actually free before using it.
Use dynamic_irq_init_keep_chip_data instead of
dynamic_irq_init so that chip_data is not NULL (a NULL chip_data breaks
setup_vector_irq).
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
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>
Add the xen pci platform device driver that is responsible
for initializing the grant table and xenbus in PV on HVM mode.
Few changes to xenbus and grant table are necessary to allow the delayed
initialization in HVM mode.
Grant table needs few additional modifications to work in HVM mode.
The Xen PCI platform device raises an irq every time an event has been
delivered to us. However these interrupts are only delivered to vcpu 0.
The Xen PCI platform interrupt handler calls xen_hvm_evtchn_do_upcall
that is a little wrapper around __xen_evtchn_do_upcall, the traditional
Xen upcall handler, the very same used with traditional PV guests.
When running on HVM the event channel upcall is never called while in
progress because it is a normal Linux irq handler (and we cannot switch
the irq chip wholesale to the Xen PV ones as we are running QEMU and
might have passed in PCI devices), therefore we cannot be sure that
evtchn_upcall_pending is 0 when returning.
For this reason if evtchn_upcall_pending is set by Xen we need to loop
again on the event channels set pending otherwise we might loose some
event channel deliveries.
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>
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>
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>
* xen_create_contiguous_region needs access to the balloon lock to
ensure memory doesn't change under its feet, so expose the balloon
lock
* Change the name of the lock to xen_reservation_lock, to imply it's
now less-specific usage.
[ Impact: cleanup ]
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>
Since the device we are resuming could be the device containing the
swap device we should ensure that the allocation cannot cause
IO.
On resume, this path is triggered when the running system tries to
continue using its devices. If it cannot then the resume will fail;
to try to avoid this we let it dip into the emergency pools.
The majority of these changes were made when linux-2.6.18-xen.hg
changeset e8b49cfbdac0 was ported upstream in
a144ff09bc but somehow this hunk was
dropped.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Stable Kernel <stable@kernel.org> # .32.x
The Xen event-channel device is named evtchn in the kernel but always
used as /dev/xen/evtchn in userspace. This patch fixes the name.
Signed-off-by: Bastian Blank <waldi@debian.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
unbind_from_irqhandler can end up doing /proc operations, which can't
happen under a spinlock. So before removing the IRQ handler,
disable the irq under the port_user lock (masking the underlying event
channel and making sure the irq handler isn't running concurrently and
won't start running), then remove the handler without the lock.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Fix build error when CONFIG_MAGIC_SYSRQ is not enabled:
drivers/xen/manage.c:223: error: implicit declaration of function 'handle_sysrq'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reimplement stop_machine using cpu_stop. As cpu stoppers are
guaranteed to be available for all online cpus,
stop_machine_create/destroy() are no longer necessary and removed.
With resource management and synchronization handled by cpu_stop, the
new implementation is much simpler. Asking the cpu_stop to execute
the stop_cpu() state machine on all online cpus with cpu hotplug
disabled is enough.
stop_machine itself doesn't need to manage any global resources
anymore, so all per-instance information is rolled into struct
stop_machine_data and the mutex and all static data variables are
removed.
The previous implementation created and destroyed RT workqueues as
necessary which made stop_machine() calls highly expensive on very
large machines. According to Dimitri Sivanich, preventing the dynamic
creation/destruction makes booting faster more than twice on very
large machines. cpu_stop resources are preallocated for all online
cpus and should have the same effect.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
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>
Constify struct sysfs_ops.
This is part of the ops structure constification
effort started by Arjan van de Ven et al.
Benefits of this constification:
* prevents modification of data that is shared
(referenced) by many other structure instances
at runtime
* detects/prevents accidental (but not intentional)
modification attempts on archs that enforce
read-only kernel data at runtime
* potentially better optimized code as the compiler
can assume that the const data cannot be changed
* the compiler/linker move const data into .rodata
and therefore exclude them from false sharing
Signed-off-by: Emese Revfy <re.emese@gmail.com>
Acked-by: David Teigland <teigland@redhat.com>
Acked-by: Matt Domsch <Matt_Domsch@dell.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Acked-by: Hans J. Koch <hjk@linutronix.de>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently the xen support drivers are displayed in the main Device Drivers
menu of the config tools instead of in their own sub-menu, so move them to
their own sub-menu, like the rest of the driver world uses.
This keeps the main Device Drivers menu from becoming messy.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now xen's use of the x86 and ia64 handle_irq is just bizarre and very
fragile as it is very non-obvious the function exists and is is used by
code out in drivers/.... Luckily using handle_irq is completely unnecessary,
and we can just use the generic irq apis instead.
This still leaves drivers/xen/events.c as a problematic user of the generic
irq apis it has "static struct irq_info irq_info[NR_IRQS]" but that can be
fixed some other time.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
LKML-Reference: <4B7CAAD2.10803@kernel.org>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
In 65f63384 "xen: improve error handling in do_suspend" I said:
- xs_suspend()/xs_resume() and dpm_suspend_noirq()/dpm_resume_noirq() were not
nested in the obvious way.
and changed the ordering of the calls as so:
BEFORE AFTER
xs_suspend dpm_suspend_noirq
dpm_suspend_noirq xs_suspend
*SUSPEND* *SUSPEND*
dpm_resume_noirq dpm_resume_noirq
xs_resume xs_resume
Clearly this is not an improvement and I was talking rubbish.
In particular the new ordering is susceptible to a hang if a xenstore write is
in progress at the point at which the suspend kicks in. When the suspend
process calls xs_suspend it tries to take the request_mutex but if a write is
in progress it could be looping in xenbus_xs.c:read_reply() waiting for
something to arrive on &xs_state.reply_list while holding the request_mutex
(taken in the caller of read_reply).
However if we have done dpm_suspend_noirq before xs_suspend then we won't get
any more xenstore interrupts and process_msg() will never be woken up to add
anything to the reply_list.
Fix this by calling xs_suspend before dpm_suspend_noirq. If dpm_suspend_noirq
fails then make sure we go through the xs_suspend_cancel() code path.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
* '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
