linux-toradex.git/drivers/pci/xen-pcifront.c, branch v3.12.32

xen/pvhvm: If xen_platform_pci=0 is set don't blow up (v4).

2014-02-13T21:50:10+00:00

commit 51c71a3bbaca868043cc45b3ad3786dd48a90235 upstream.

The user has the option of disabling the platform driver:
00:02.0 Unassigned class [ff80]: XenSource, Inc. Xen Platform Device (rev 01)

which is used to unplug the emulated drivers (IDE, Realtek 8169, etc)
and allow the PV drivers to take over. If the user wishes
to disable that they can set:

  xen_platform_pci=0
  (in the guest config file)

or
  xen_emul_unplug=never
  (on the Linux command line)

except it does not work properly. The PV drivers still try to
load and since the Xen platform driver is not run - and it
has not initialized the grant tables, most of the PV drivers
stumble upon:

input: Xen Virtual Keyboard as /devices/virtual/input/input5
input: Xen Virtual Pointer as /devices/virtual/input/input6M
------------[ cut here ]------------
kernel BUG at /home/konrad/ssd/konrad/linux/drivers/xen/grant-table.c:1206!
invalid opcode: 0000 [#1] SMP
Modules linked in: xen_kbdfront(+) xenfs xen_privcmd
CPU: 6 PID: 1389 Comm: modprobe Not tainted 3.13.0-rc1upstream-00021-ga6c892b-dirty #1
Hardware name: Xen HVM domU, BIOS 4.4-unstable 11/26/2013
RIP: 0010:[]  [] get_free_entries+0x2e0/0x300
Call Trace:
 [] ? evdev_connect+0x1e3/0x240
 [] gnttab_grant_foreign_access+0x2e/0x70
 [] xenkbd_connect_backend+0x41/0x290 [xen_kbdfront]
 [] xenkbd_probe+0x2f2/0x324 [xen_kbdfront]
 [] xenbus_dev_probe+0x77/0x130
 [] xenbus_frontend_dev_probe+0x47/0x50
 [] driver_probe_device+0x89/0x230
 [] __driver_attach+0x9b/0xa0
 [] ? driver_probe_device+0x230/0x230
 [] ? driver_probe_device+0x230/0x230
 [] bus_for_each_dev+0x8c/0xb0
 [] driver_attach+0x19/0x20
 [] bus_add_driver+0x1a0/0x220
 [] driver_register+0x5f/0xf0
 [] xenbus_register_driver_common+0x15/0x20
 [] xenbus_register_frontend+0x23/0x40
 [] ? 0xffffffffa0014fff
 [] xenkbd_init+0x2b/0x1000 [xen_kbdfront]
 [] do_one_initcall+0x49/0x170

.. snip..

which is hardly nice. This patch fixes this by having each
PV driver check for:
 - if running in PV, then it is fine to execute (as that is their
   native environment).
 - if running in HVM, check if user wanted 'xen_emul_unplug=never',
   in which case bail out and don't load any PV drivers.
 - if running in HVM, and if PCI device 5853:0001 (xen_platform_pci)
   does not exist, then bail out and not load PV drivers.
 - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=ide-disks',
   then bail out for all PV devices _except_ the block one.
   Ditto for the network one ('nics').
 - (v2) if running in HVM, and if the user wanted 'xen_emul_unplug=unnecessary'
   then load block PV driver, and also setup the legacy IDE paths.
   In (v3) make it actually load PV drivers.

Reported-by: Sander Eikelenboom 
Reported-and-Tested-by: Fabio Fantoni 
Signed-off-by: Konrad Rzeszutek Wilk 
[v2: Add extra logic to handle the myrid ways 'xen_emul_unplug'
can be used per Ian and Stefano suggestion]
[v3: Make the unnecessary case work properly]
[v4: s/disks/ide-disks/ spotted by Fabio]
Reviewed-by: Stefano Stabellini 
Acked-by: Bjorn Helgaas  [for PCI parts]
Signed-off-by: Greg Kroah-Hartman

xen/pcifront: Deal with toolstack missing 'XenbusStateClosing' state.

2013-06-14T16:28:59+00:00

There are two tool-stack that can instruct the Xen PCI frontend
and backend to change states: 'xm' (Python code with a daemon),
and 'xl' (C library - does not keep state changes).

With the 'xm', the path to disconnect a single PCI device (xm pci-detach
 ) is:

4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected)->5(Closing*).

The * is for states that the tool-stack sets. For 'xl', it is similar:

4(Connected)->7(Reconfiguring*)-> 8(Reconfigured)-> 4(Connected)

Both of them also tear down the XenBus structure, so the backend
state ends up going in the 3(Initialised) and calls pcifront_xenbus_remove.

When a PCI device is plugged back in (xm pci-attach  )
both of them follow the same pattern:

2(InitWait*), 3(Initialized*), 4(Connected*)->4(Connected).

[xen-pcifront ignores the 2,3 state changes and only acts when
4 (Connected) has been reached]

Note that this is for a _single_ PCI device. If there were two
PCI devices and only one was disconnected 'xm' would show the same
state changes.

The problem is that git commit 3d925320e9e2de162bd138bf97816bda8c3f71be
("xen/pcifront: Use Xen-SWIOTLB when initting if required") introduced
a mechanism to initialize the SWIOTLB when the Xen PCI front moves to
Connected state. It also had some aggressive seatbelt code check that
would warn the user if one tried to change to Connected state without
hitting first the Closing state:

 pcifront pci-0: PCI frontend already installed!

However, that code can be relaxed and we can continue on working
even if the frontend is instructed to be the 'Connected' state with
no devices and then gets tickled to be in 'Connected' state again.

In other words, this 4(Connected)->5(Closing)->4(Connected) state
was expected, while 4(Connected)->.... anything but 5(Closing)->4(Connected)
was not. This patch removes that aggressive check and allows
Xen pcifront to work with the 'xl' toolstack (for one or more
PCI devices) and with 'xm' toolstack (for more than two PCI
devices).

Acked-by: Bjorn Helgaas 
Cc: linux-pci@vger.kernel.org
Cc: stable@vger.kernel.org
[v2: Added in the description about two PCI devices]
Signed-off-by: Konrad Rzeszutek Wilk

Merge tag 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

2012-12-13T20:14:47+00:00

Pull PCI update from Bjorn Helgaas:
 "Host bridge hotplug:
   - Untangle _PRT from struct pci_bus (Bjorn Helgaas)
   - Request _OSC control before scanning root bus (Taku Izumi)
   - Assign resources when adding host bridge (Yinghai Lu)
   - Remove root bus when removing host bridge (Yinghai Lu)
   - Remove _PRT during hot remove (Yinghai Lu)

  SRIOV
    - Add sysfs knobs to control numVFs (Don Dutile)

  Power management
   - Notify devices when power resource turned on (Huang Ying)

  Bug fixes
   - Work around broken _SEG on HP xw9300 (Bjorn Helgaas)
   - Keep runtime PM enabled for unbound PCI devices (Huang Ying)
   - Fix Optimus dual-GPU runtime D3 suspend issue (Dave Airlie)
   - Fix xen frontend shutdown issue (David Vrabel)
   - Work around PLX PCI 9050 BAR alignment erratum (Ian Abbott)

  Miscellaneous
   - Add GPL license for drivers/pci/ioapic (Andrew Cooks)
   - Add standard PCI-X, PCIe ASPM register #defines (Bjorn Helgaas)
   - NumaChip remote PCI support (Daniel Blueman)
   - Fix PCIe Link Capabilities Supported Link Speed definition (Jingoo
     Han)
   - Convert dev_printk() to dev_info(), etc (Joe Perches)
   - Add support for non PCI BAR ROM data (Matthew Garrett)
   - Add x86 support for host bridge translation offset (Mike Yoknis)
   - Report success only when every driver supports AER (Vijay
     Pandarathil)"

Fix up trivial conflicts.

* tag 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (48 commits)
  PCI: Use phys_addr_t for physical ROM address
  x86/PCI: Add NumaChip remote PCI support
  ath9k: Use standard #defines for PCIe Capability ASPM fields
  iwlwifi: Use standard #defines for PCIe Capability ASPM fields
  iwlwifi: collapse wrapper for pcie_capability_read_word()
  iwlegacy: Use standard #defines for PCIe Capability ASPM fields
  iwlegacy: collapse wrapper for pcie_capability_read_word()
  cxgb3: Use standard #defines for PCIe Capability ASPM fields
  PCI: Add standard PCIe Capability Link ASPM field names
  PCI/portdrv: Use PCI Express Capability accessors
  PCI: Use standard PCIe Capability Link register field names
  x86: Use PCI setup data
  PCI: Add support for non-BAR ROMs
  PCI: Add pcibios_add_device
  EFI: Stash ROMs if they're not in the PCI BAR
  PCI: Add and use standard PCI-X Capability register names
  PCI/PM: Keep runtime PM enabled for unbound PCI devices
  xen-pcifront: Handle backend CLOSED without CLOSING
  PCI: SRIOV control and status via sysfs (documentation)
  PCI/AER: Report success only when every device has AER-aware driver
  ...

xen-pcifront: Handle backend CLOSED without CLOSING

2012-11-30T21:33:35+00:00

Backend drivers shouldn't transition to CLOSED unless the frontend is
CLOSED.  If a backend does transition to CLOSED too soon then the
frontend may not see the CLOSING state and will not properly shutdown.

So, treat an unexpected backend CLOSED state the same as CLOSING.

Signed-off-by: David Vrabel 
Signed-off-by: Bjorn Helgaas 
Acked-by: Konrad Rzeszutek Wilk

PCI: Remove __dev* markings

2012-11-28T21:16:47+00:00

CONFIG_HOTPLUG is going away as an option so __devexit_p, __devint,
__devinitdata, __devinitconst, and _devexit are no longer needed.

Signed-off-by: Bill Pemberton 
Acked-by: Bjorn Helgaas 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'stable/for-linus-3.7-x86-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

2012-10-03T05:09:10+00:00

Pull Xen update from Konrad Rzeszutek Wilk:
 "Features:
   - When hotplugging PCI devices in a PV guest we can allocate
     Xen-SWIOTLB later.
   - Cleanup Xen SWIOTLB.
   - Support pages out grants from HVM domains in the backends.
   - Support wild cards in xen-pciback.hide=(BDF) arguments.
   - Update grant status updates with upstream hypervisor.
   - Boot PV guests with more than 128GB.
   - Cleanup Xen MMU code/add comments.
   - Obtain XENVERS using a preferred method.
   - Lay out generic changes to support Xen ARM.
   - Allow privcmd ioctl for HVM (used to do only PV).
   - Do v2 of mmap_batch for privcmd ioctls.
   - If hypervisor saves the LED keyboard light - we will now instruct
     the kernel about its state.
  Fixes:
   - More fixes to Xen PCI backend for various calls/FLR/etc.
   - With more than 4GB in a 64-bit PV guest disable native SWIOTLB.
   - Fix up smatch warnings.
   - Fix up various return values in privmcmd and mm."

* tag 'stable/for-linus-3.7-x86-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (48 commits)
  xen/pciback: Restore the PCI config space after an FLR.
  xen-pciback: properly clean up after calling pcistub_device_find()
  xen/vga: add the xen EFI video mode support
  xen/x86: retrieve keyboard shift status flags from hypervisor.
  xen/gndev: Xen backend support for paged out grant targets V4.
  xen-pciback: support wild cards in slot specifications
  xen/swiotlb: Fix compile warnings when using plain integer instead of NULL pointer.
  xen/swiotlb: Remove functions not needed anymore.
  xen/pcifront: Use Xen-SWIOTLB when initting if required.
  xen/swiotlb: For early initialization, return zero on success.
  xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used.
  xen/swiotlb: Move the error strings to its own function.
  xen/swiotlb: Move the nr_tbl determination in its own function.
  xen/arm: compile and run xenbus
  xen: resynchronise grant table status codes with upstream
  xen/privcmd: return -EFAULT on error
  xen/privcmd: Fix mmap batch ioctl error status copy back.
  xen/privcmd: add PRIVCMD_MMAPBATCH_V2 ioctl
  xen/mm: return more precise error from xen_remap_domain_range()
  xen/mmu: If the revector fails, don't attempt to revector anything else.
  ...

Merge branch 'stable/late-swiotlb.v3.3' into stable/for-linus-3.7

2012-09-23T00:01:24+00:00

* stable/late-swiotlb.v3.3:
  xen/swiotlb: Fix compile warnings when using plain integer instead of NULL pointer.
  xen/swiotlb: Remove functions not needed anymore.
  xen/pcifront: Use Xen-SWIOTLB when initting if required.
  xen/swiotlb: For early initialization, return zero on success.
  xen/swiotlb: Use the swiotlb_late_init_with_tbl to init Xen-SWIOTLB late when PV PCI is used.
  xen/swiotlb: Move the error strings to its own function.
  xen/swiotlb: Move the nr_tbl determination in its own function.
  swiotlb: add the late swiotlb initialization function with iotlb memory
  xen/swiotlb: With more than 4GB on 64-bit, disable the native SWIOTLB.
  xen/swiotlb: Simplify the logic.

Conflicts:
	arch/x86/xen/pci-swiotlb-xen.c

Signed-off-by: Konrad Rzeszutek Wilk

xen/pcifront: Use Xen-SWIOTLB when initting if required.

2012-09-17T17:00:42+00:00

We piggyback on "xen/swiotlb: Use the swiotlb_late_init_with_tbl to init
Xen-SWIOTLB late when PV PCI is used." functionality to start up
the Xen-SWIOTLB if we are hot-plugged. This allows us to bypass
the need to supply 'iommu=soft' on the Linux command line (mostly).
With this patch, if a user forgot 'iommu=soft' on the command line,
and hotplug a PCI device they will get:

pcifront pci-0: Installing PCI frontend
Warning: only able to allocate 4 MB for software IO TLB
software IO TLB [mem 0x2a000000-0x2a3fffff] (4MB) mapped at [ffff88002a000000-ffff88002a3fffff]
pcifront pci-0: Creating PCI Frontend Bus 0000:00
pcifront pci-0: PCI host bridge to bus 0000:00
pci_bus 0000:00: root bus resource [io  0x0000-0xffff]
pci_bus 0000:00: root bus resource [mem 0x00000000-0xfffffffff]
pci 0000:00:00.0: [8086:10d3] type 00 class 0x020000
pci 0000:00:00.0: reg 10: [mem 0xfe5c0000-0xfe5dffff]
pci 0000:00:00.0: reg 14: [mem 0xfe500000-0xfe57ffff]
pci 0000:00:00.0: reg 18: [io  0xe000-0xe01f]
pci 0000:00:00.0: reg 1c: [mem 0xfe5e0000-0xfe5e3fff]
pcifront pci-0: claiming resource 0000:00:00.0/0
pcifront pci-0: claiming resource 0000:00:00.0/1
pcifront pci-0: claiming resource 0000:00:00.0/2
pcifront pci-0: claiming resource 0000:00:00.0/3
e1000e: Intel(R) PRO/1000 Network Driver - 2.0.0-k
e1000e: Copyright(c) 1999 - 2012 Intel Corporation.
e1000e 0000:00:00.0: Disabling ASPM L0s L1
e1000e 0000:00:00.0: enabling device (0000 -> 0002)
e1000e 0000:00:00.0: Xen PCI mapped GSI16 to IRQ34
e1000e 0000:00:00.0: (unregistered net_device): Interrupt Throttling Rate (ints/sec) set to dynamic conservative mode
e1000e 0000:00:00.0: eth0: (PCI Express:2.5GT/s:Width x1) 00:1b:21:ab:c6:13
e1000e 0000:00:00.0: eth0: Intel(R) PRO/1000 Network Connection
e1000e 0000:00:00.0: eth0: MAC: 3, PHY: 8, PBA No: E46981-005

The "Warning only" will go away if one supplies 'iommu=soft' instead
as we have a higher chance of being able to allocate large swaths of
memory.

Acked-by: Stefano Stabellini 
Signed-off-by: Konrad Rzeszutek Wilk

xen-pcifront: Use hotplug-safe pci_get_domain_bus_and_slot()

2012-09-12T20:15:16+00:00

Following code has a race window between pci_find_bus() and pci_get_slot()
if PCI hotplug operation happens between them which removes the pci_bus.
So use PCI hotplug safe interface pci_get_domain_bus_and_slot() instead,
which also reduces code complexity.

    struct pci_bus *pci_bus = pci_find_bus(domain, busno);
    struct pci_dev *pci_dev = pci_get_slot(pci_bus, devfn);

Tested-by: Konrad Rzeszutek Wilk 
Signed-off-by: Jiang Liu 
Signed-off-by: Bjorn Helgaas 
Acked-by: Konrad Rzeszutek Wilk

xen/apic/xenbus/swiotlb/pcifront/grant/tmem: Make functions or variables static.

2012-08-21T18:50:03+00:00

There is no need for those functions/variables to be visible. Make them
static and also fix the compile warnings of this sort:

drivers/xen/.c: warning: symbol '' was not declared. Should it be static?

Some of them just require including the header file that
declares the functions.

Signed-off-by: Konrad Rzeszutek Wilk