When unmapping grants, instead of converting the kernel map ops to
unmap ops on the fly, pre-populate the set of unmap ops.

This allows the grant unmap for the kernel mappings to be trivially
batched in the future.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

As a module_init() function, this should have been this way from the
beginning.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

This reverts commit 2c3fc8d2.

This commit broke on x86 PV because entries in the generic SWIOTLB are
indexed using (pseudo-)physical address not DMA address and these are
not the same in a x86 PV guest.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

This reverts commit 2c3fc8d2.

This commit broke on x86 PV because entries in the generic SWIOTLB are
indexed using (pseudo-)physical address not DMA address and these are
not the same in a x86 PV guest.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

When a PF driver unloads, it may find it necessary to leave the VFs
around simply because of pciback having marked them as assigned to a
guest. Utilize a suitable notification to let go of the VFs, thus
allowing the PF to go back into the state it was before its driver
loaded (which in particular allows the driver to be loaded again with
it being able to create the VFs anew, but which also allows to then
pass through the PF instead of the VFs).

Don't do this however for any VFs currently in active use by a guest.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
[v2: Removed the switch statement, moved it about]
[v3: Redid it a bit differently]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The commit "xen/pciback: Don't deadlock when unbinding." was using
the version of pci_reset_function which would lock the device lock.
That is no good as we can dead-lock. As such we swapped to using
the lock-less version and requiring that the callers
of 'pcistub_put_pci_dev' take the device lock. And as such
this bug got exposed.

Using the lock-less version is  OK, except that we tried to
use 'pci_restore_state' after the lock-less version of
__pci_reset_function_locked - which won't work as 'state_saved'
is set to false. Said 'state_saved' is a toggle boolean that
is to be used by the sequence of a) pci_save_state/pci_restore_state
or b) pci_load_and_free_saved_state/pci_restore_state. We don't
want to use a) as the guest might have messed up the PCI
configuration space and we want it to revert to the state
when the PCI device was binded to us. Therefore we pick
b) to restore the configuration space.

We restore from our 'golden' version of PCI configuration space, when an:
 - Device is unbinded from pciback
 - Device is detached from a guest.
Reported-by: NSander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

A little cleanup. No functional difference.
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

We had been printing it only if the device was built with
debug enabled. But this information is useful in the field
to troubleshoot.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Cleanup the function a bit - also include the id of the
domain that is using the device.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Instead of open-coding it in drivers that want to double check
that their functions are indeed holding the device lock.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Suggested-by: NDavid Vrabel <david.vrabel@citrix.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

As commit 0a9fd015
'xen/pciback: Document the entry points for 'pcistub_put_pci_dev''
explained there are four entry points in this function.
Two of them are when the user fiddles in the SysFS to
unbind a device which might be in use by a guest or not.

Both 'unbind' states will cause a deadlock as the the PCI lock has
already been taken, which then pci_device_reset tries to take.

We can simplify this by requiring that all callers of
pcistub_put_pci_dev MUST hold the device lock. And then
we can just call the lockless version of pci_device_reset.

To make it even simpler we will modify xen_pcibk_release_pci_dev
to quality whether it should take a lock or not - as it ends
up calling xen_pcibk_release_pci_dev and needs to hold the lock.
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Need to pass the pointer within the swiotlb internal buffer to the
swiotlb library, that in the case of xen_unmap_single is dev_addr, not
paddr.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org

In xen_swiotlb_sync_single we always call xen_dma_sync_single_for_cpu,
even when we should call xen_dma_sync_single_for_device. Fix that.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org

On x86 truncation cannot occur because config XEN depends on X86_64 ||
(X86_32 && X86_PAE).

On ARM truncation can occur without CONFIG_ARM_LPAE, when the dma
operation involves foreign grants. However in that case the physical
address returned by xen_bus_to_phys is actually invalid (there is no mfn
to pfn tracking for foreign grants on ARM) and it is not used.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org

xen_dma_unmap_page and xen_dma_sync_single_for_cpu take a dma_addr_t
handle as argument, not a physical address.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: stable@vger.kernel.org

Introduce an arch specific function to find out whether a particular dma
mapping operation needs to bounce on the swiotlb buffer.

On ARM and ARM64, if the page involved is a foreign page and the device
is not coherent, we need to bounce because at unmap time we cannot
execute any required cache maintenance operations (we don't know how to
find the pfn from the mfn).

No change of behaviour for x86.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NIan Campbell <ian.campbell@citrix.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

dev_addr is the machine address of the page.

The new parameter can be used by the ARM and ARM64 implementations of
xen_dma_map_page to find out if the page is a local page (pfn == mfn) or
a foreign page (pfn != mfn).

dev_addr could be retrieved again from the physical address, using
pfn_to_mfn, but it requires accessing an rbtree. Since we already have
the dev_addr in our hands at the call site there is no need to get the
mfn twice.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

For SPI drivers use the message definitions from scsi.h, and for target
drivers introduce a new TCM_*_TAG namespace.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com

We should be using the standard dev_printk() variants for
sense code printing.

[hch: remove __scsi_print_sense call in xen-scsiback, Acked by Juergen]
[hch: folded bracing fix from Dan Carpenter]
Signed-off-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NRobert Elliott <elliott@hp.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

This adds support to the UEFI side for detecting the presence of
a SMBIOS 3.0 64-bit entry point. This allows the actual SMBIOS
structure table to reside at a physical offset over 4 GB, which
cannot be supported by the legacy SMBIOS 32-bit entry point.

Since the firmware can legally provide both entry points, store
the SMBIOS 3.0 entry point in a separate variable, and let the
DMI decoding layer decide which one will be used.
Tested-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Acked-by: NLeif Lindholm <leif.lindholm@linaro.org>
Acked-by: NMatt Fleming <matt.fleming@intel.com>
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>

physdev_pci_device_add's optarr[] is a zero-sized array and therefore
reference to add.optarr[0] is accessing memory that does not belong to
the 'add' variable.
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Commit 3dcf6367 ("xen/balloon: cancel ballooning if adding new
memory failed") makes reserve_additional_memory() return BP_ECANCELED
when an error is encountered. This error, however, is ignored by the
caller (balloon_process()) since it is overwritten by subsequent call
to update_schedule(). This results in continuous attempts to add more
memory, all of which are likely to fail again.

We should stop trying to schedule next iteration of ballooning when
the current one has failed.
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NDaniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse
errors.

Replace the uses with standard structure definitions instead.  This is
similar to pci and usb device registration.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

xenbus_va_dev_error() is for printing error, so when error string is
too long to be truncated, need not BUG_ON(), still return truncation
string is OK.
Signed-off-by: NChen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

A grant reference (which is a positive number) can indicate success, so
the original comments need be improved.
Signed-off-by: NChen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

I discovered that some needed stuff is defined/declared in headers
which are not included directly. Currently it works but if somebody
remove required headers from currently included headers then build
will break. So, just in case directly include all needed headers.
Signed-off-by: NDaniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

This code was confusing because we had an unsigned long and then we
compared it to UINT_MAX and then we stored it in a u16.  How many bytes
is this supposed to have: 2, 4 or 16???

I've made it a u16 throughout.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Introduces the Xen pvSCSI backend. With pvSCSI it is possible for a
Xen domU to issue SCSI commands to a SCSI LUN assigned to that
domU. The SCSI commands are passed to the pvSCSI backend in a driver
domain (usually Dom0) which is owner of the physical device. This
allows e.g. to use SCSI tape drives in a Xen domU.

The code is taken from the pvSCSI implementation in Xen done by
Fujitsu based on Linux kernel 2.6.18.

Changes from the original version are:
- port to upstream kernel
- put all code in just one source file
- adapt to Linux style guide
- use target core infrastructure instead doing pure pass-through
- enable module unloading
- support SG-list in grant page(s)
- support task abort
- remove redundant struct backend
- allocate resources dynamically
- correct minor error in scsiback_fast_flush_area
- free allocated resources in case of error during I/O preparation
- remove CDB emulation, now handled by target core infrastructure
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NNicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Export bind_interdomain_evtchn_to_irq() so drivers can use threaded
interrupt handlers with:

 irq = bind_interdomain_evtchn_to_irq(remote_dom, remote_port);
 if (irq < 0)
     /* error */
 ret = request_threaded_irq(...);
Signed-off-by: NJuergen Gross <jgross@suse.com>
Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The cleanup loop in grow_gnttab_list() is safe from the underflow of
the unsigned 'i' since nr_glist_frames is >= 1, but refactor it
anyway.
Signed-off-by: NChen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Use PCI device flag helper functions when assigning or releasing device.
No functional change.
Signed-off-by: NEthan Zhao <ethan.zhao@oracle.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NDavid Vrabel <david.vrabel@citrix.com>

If a gref could not be added (perhaps because the limit has been
reached or there are no more grant references available), the undo
path may crash because __del_gref() frees the gref while it is being
used for a list iteration.

A comment suggests that using list_for_each_entry() is safe since the
gref isn't removed from the list being iterated over, but it is freed
and thus list_for_each_entry_safe() must be used.

Also, explicitly delete the gref from the local per-file list, even
though this is not strictly necessary.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

Only set gref->gref_id if foreign access was successfully granted and
the grant ref is valid.

If gref->gref_id == -ENOSPC the test in __del_gref() would incorrectly
attempt to end foreign access (because grant_ref_t is unsigned).
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reported-by: NDave Scott <dave.scott@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

If the balloon driver is adding additional memory regions to the
balloon and add_memory() fails it will likely continuously fail so
cancel the balloon operation.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NDaniel Kiper <daniel.kiper@oracle.com>

Always freeze processes when suspending and thaw processes when resuming
to prevent a race noticeable with HVM guests.

This prevents a deadlock where the khubd kthread (which is designed to
be freezable) acquires a usb device lock and then tries to allocate
memory which requires the disk which hasn't been resumed yet.
Meanwhile, the xenwatch thread deadlocks waiting for the usb device
lock.

Freezing processes fixes this because the khubd thread is only thawed
after the xenwatch thread finishes resuming all the devices.
Signed-off-by: NRoss Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: stable@vger.kernel.org

We should prefer `struct pci_device_id` over `DEFINE_PCI_DEVICE_TABLE` to
meet kernel coding style guidelines.  This issue was reported by checkpatch.

A simplified version of the semantic patch that makes this change is as
follows (http://coccinelle.lip6.fr/):

// <smpl>

@@
identifier i;
declarer name DEFINE_PCI_DEVICE_TABLE;
initializer z;
@@

- DEFINE_PCI_DEVICE_TABLE(i)
+ const struct pci_device_id i[]
= z;

// </smpl>

[bhelgaas: add semantic patch]
Signed-off-by: NBenoit Taine <benoit.taine@lip6.fr>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

Fix to return -EFAULT from the error handling case instead of 0 when
version mismatch with pcifront.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Reviewed-by Jan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=80531Reported-by: NDavid Binderman <dcb314@hotmail.com>
Signed-off-by: NAndrey Utkin <andrey.krieger.utkin@gmail.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Since 05a812ac (xen/events/fifo:
correctly align bitops), ready is an unsigned long instead of uint32_t
and the BM() macro is no longer required.
Signed-off-by: NFrediano Ziglio <frediano.ziglio@citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

When using the FIFO-based ABI on x86_64, if the last port is at the
end of an event array page then sync_test_bit() on this port's event
word will read beyond the end of the page and in certain circumstances
this may fault.

The fault requires the following page in the kernel's direct mapping
to be not present, which would mean:

a) the array page is the last page of RAM; or

b) the following page is ballooned out /and/ it has been used for a
   foreign mapping by a kernel driver (such as netback or blkback)
   /and/ the grant has been unmapped.

Use the infrastructure added for arm64 to ensure that all bitops
operating on event words are unsigned long aligned.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org