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path: root/drivers/xen/grant-table.c
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2018-02-06xen/grant-table: Use put_page instead of free_pageRoss Lagerwall
The page given to gnttab_end_foreign_access() to free could be a compound page so use put_page() instead of free_page() since it can handle both compound and single pages correctly. This bug was discovered when migrating a Xen VM with several VIFs and CONFIG_DEBUG_VM enabled. It hits a BUG usually after fewer than 10 iterations. All netfront devices disconnect from the backend during a suspend/resume and this will call gnttab_end_foreign_access() if a netfront queue has an outstanding skb. The mismatch between calling get_page() and free_page() on a compound page causes a reference counting error which is detected when DEBUG_VM is enabled. Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-11-21treewide: Switch DEFINE_TIMER callbacks to struct timer_list *Kees Cook
This changes all DEFINE_TIMER() callbacks to use a struct timer_list pointer instead of unsigned long. Since the data argument has already been removed, none of these callbacks are using their argument currently, so this renames the argument to "unused". Done using the following semantic patch: @match_define_timer@ declarer name DEFINE_TIMER; identifier _timer, _callback; @@ DEFINE_TIMER(_timer, _callback); @change_callback depends on match_define_timer@ identifier match_define_timer._callback; type _origtype; identifier _origarg; @@ void -_callback(_origtype _origarg) +_callback(struct timer_list *unused) { ... } Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-16Merge tag 'for-linus-4.15-rc1-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen updates from Juergen Gross: "Xen features and fixes for v4.15-rc1 Apart from several small fixes it contains the following features: - a series by Joao Martins to add vdso support of the pv clock interface - a series by Juergen Gross to add support for Xen pv guests to be able to run on 5 level paging hosts - a series by Stefano Stabellini adding the Xen pvcalls frontend driver using a paravirtualized socket interface" * tag 'for-linus-4.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (34 commits) xen/pvcalls: fix potential endless loop in pvcalls-front.c xen/pvcalls: Add MODULE_LICENSE() MAINTAINERS: xen, kvm: track pvclock-abi.h changes x86/xen/time: setup vcpu 0 time info page x86/xen/time: set pvclock flags on xen_time_init() x86/pvclock: add setter for pvclock_pvti_cpu0_va ptp_kvm: probe for kvm guest availability xen/privcmd: remove unused variable pageidx xen: select grant interface version xen: update arch/x86/include/asm/xen/cpuid.h xen: add grant interface version dependent constants to gnttab_ops xen: limit grant v2 interface to the v1 functionality xen: re-introduce support for grant v2 interface xen: support priv-mapping in an HVM tools domain xen/pvcalls: remove redundant check for irq >= 0 xen/pvcalls: fix unsigned less than zero error check xen/time: Return -ENODEV from xen_get_wallclock() xen/pvcalls-front: mark expected switch fall-through xen: xenbus_probe_frontend: mark expected switch fall-throughs xen/time: do not decrease steal time after live migration on xen ...
2017-11-06xen: select grant interface versionJuergen Gross
Grant v2 will be needed in cases where a frame number in the grant table can exceed 32 bits. For PV guests this is a host feature, while for HVM guests this is a guest feature. So select grant v2 in case frame numbers can be larger than 32 bits and grant v1 else. For testing purposes add a way to specify the grant interface version via a boot parameter. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-11-06xen: add grant interface version dependent constants to gnttab_opsJuergen Gross
Instead of having multiple variables with constants like grant_table_version or grefs_per_grant_frame add those to struct gnttab_ops and access them just via the gnttab_interface pointer. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-11-06xen: limit grant v2 interface to the v1 functionalityJuergen Gross
As there is currently no user for sub-page grants or transient grants remove that functionality. This at once makes it possible to switch from grant v2 to grant v1 without restrictions, as there is no loss of functionality other than the limited frame number width related to the switch. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-11-06xen: re-introduce support for grant v2 interfaceJuergen Gross
The grant v2 support was removed from the kernel with commit 438b33c7145ca8a5131a30c36d8f59bce119a19a ("xen/grant-table: remove support for V2 tables") as the higher memory footprint of v2 grants resulted in less grants being possible for a kernel compared to the v1 grant interface. As machines with more than 16TB of memory are expected to be more common in the near future support of grant v2 is mandatory in order to be able to run a Xen pv domain at any memory location. So re-add grant v2 support basically by reverting above commit. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-10-05timer: Remove expires and data arguments from DEFINE_TIMERKees Cook
Drop the arguments from the macro and adjust all callers with the following script: perl -pi -e 's/DEFINE_TIMER\((.*), 0, 0\);/DEFINE_TIMER($1);/g;' \ $(git grep DEFINE_TIMER | cut -d: -f1 | sort -u | grep -v timer.h) Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # for m68k parts Acked-by: Guenter Roeck <linux@roeck-us.net> # for watchdog parts Acked-by: David S. Miller <davem@davemloft.net> # for networking parts Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Kalle Valo <kvalo@codeaurora.org> # for wireless parts Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: linux-mips@linux-mips.org Cc: Petr Mladek <pmladek@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Sebastian Reichel <sre@kernel.org> Cc: Kalle Valo <kvalo@qca.qualcomm.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Pavel Machek <pavel@ucw.cz> Cc: linux1394-devel@lists.sourceforge.net Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: linux-s390@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com> Cc: Wim Van Sebroeck <wim@iguana.be> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Ursula Braun <ubraun@linux.vnet.ibm.com> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Harish Patil <harish.patil@cavium.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Michael Reed <mdr@sgi.com> Cc: Manish Chopra <manish.chopra@cavium.com> Cc: Len Brown <len.brown@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: linux-pm@vger.kernel.org Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Julian Wiedmann <jwi@linux.vnet.ibm.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Mark Gross <mark.gross@intel.com> Cc: linux-watchdog@vger.kernel.org Cc: linux-scsi@vger.kernel.org Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Guenter Roeck <linux@roeck-us.net> Cc: netdev@vger.kernel.org Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linuxppc-dev@lists.ozlabs.org Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Link: https://lkml.kernel.org/r/1507159627-127660-11-git-send-email-keescook@chromium.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-07-23xen/grant-table: log the lack of grantsWengang Wang
log a message when we enter this situation: 1) we already allocated the max number of available grants from hypervisor and 2) we still need more (but the request fails because of 1)). Sometimes the lack of grants causes IO hangs in xen_blkfront devices. Adding this log would help debuging. Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2017-02-07xen/pvh: Initialize grant table for PVH guestsBoris Ostrovsky
Like PV guests, PVH does not have PCI devices and therefore cannot use MMIO space to store grants. Instead it balloons out memory and keeps grants there. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com>
2016-03-21xen: audit usages of module.h ; remove unnecessary instancesPaul Gortmaker
Code that uses no modular facilities whatsoever should not be sourcing module.h at all, since that header drags in a bunch of other headers with it. Similarly, code that is not explicitly using modular facilities like module_init() but only is declaring module_param setup variables should be using moduleparam.h and not the larger module.h file for that. In making this change, we also uncover an implicit use of BUG() in inline fcns within arch/arm/include/asm/xen/hypercall.h so we explicitly source <linux/bug.h> for that file now. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-12-21xen/grant-table: constify gnttab_ops structureJulia Lawall
The gnttab_ops structure is never modified, so declare it as const. Done with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23xen/grant-table: Add an helper to iterate over a specific number of grantsJulien Grall
With the 64KB page granularity support on ARM64, a Linux page may be split accross multiple grant. Currently we have the helper gnttab_foreach_grant_in_grant to break a Linux page based on an offset and a len, but it doesn't fit when we only have a number of grants in hand. Introduce a new helper which take an array of Linux page and a number of grant and will figure out the address of each grant. Signed-off-by: Julien Grall <julien.grall@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23xen/grant-table: Make it running on 64KB granularityJulien Grall
The Xen interface is using 4KB page granularity. This means that each grant is 4KB. The current implementation allocates a Linux page per grant. On Linux using 64KB page granularity, only the first 4KB of the page will be used. We could decrease the memory wasted by sharing the page with multiple grant. It will require some care with the {Set,Clear}ForeignPage macro. Note that no changes has been made in the x86 code because both Linux and Xen will only use 4KB page granularity. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23xen/grant: Introduce helpers to split a page into grantJulien Grall
Currently, a grant is always based on the Xen page granularity (i.e 4KB). When Linux is using a different page granularity, a single page will be split between multiple grants. The new helpers will be in charge of splitting the Linux page into grants and call a function given by the caller on each grant. Also provide an helper to count the number of grants within a given contiguous region. Note that the x86/include/asm/xen/page.h is now including xen/interface/grant_table.h rather than xen/grant_table.h. It's necessary because xen/grant_table.h depends on asm/xen/page.h and will break the compilation. Furthermore, only definition in interface/grant_table.h is required. Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23xen/balloon: make alloc_xenballoon_pages() always allocate low pagesDavid Vrabel
All users of alloc_xenballoon_pages() wanted low memory pages, so remove the option for high memory. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2015-06-17xen/grant-table: Remove unused macro SPPJulien Grall
SPP was used by the grant table v2 code which has been removed in commit 438b33c7145ca8a5131a30c36d8f59bce119a19a "xen/grant-table: remove support for V2 tables". Signed-off-by: Julien Grall <julien.grall@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-04-27xen/grant: introduce func gnttab_unmap_refs_sync()Bob Liu
There are several place using gnttab async unmap and wait for completion, so move the common code to a function gnttab_unmap_refs_sync(). Signed-off-by: Bob Liu <bob.liu@oracle.com> Acked-by: Roger Pau Monné <roger.pau@citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-01-28xen/grant-table: add a mechanism to safely unmap pages that are in useJennifer Herbert
Introduce gnttab_unmap_refs_async() that can be used to safely unmap pages that may be in use (ref count > 1). If the pages are in use the unmap is deferred and retried later. This polling is not very clever but it should be good enough if the cases where the delay is necessary are rare. The initial delay is 5 ms and is increased linearly on each subsequent retry (to reduce load if the page is in use for a long time). This is needed to allow block backends using grant mapping to safely use network storage (block or filesystem based such as iSCSI or NFS). The network storage driver may complete a block request whilst there is a queued network packet retry (because the ack from the remote end races with deciding to queue the retry). The pages for the retried packet would be grant unmapped and the network driver (or hardware) would access the unmapped page. Signed-off-by: Jennifer Herbert <jennifer.herbert@citrix.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-01-28xen: mark grant mapped pages as foreignJennifer Herbert
Use the "foreign" page flag to mark pages that have a grant map. Use page->private to store information of the grant (the granting domain and the grant reference). Signed-off-by: Jennifer Herbert <jennifer.herbert@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-01-28xen/grant-table: add helpers for allocating pagesDavid Vrabel
Add gnttab_alloc_pages() and gnttab_free_pages() to allocate/free pages suitable to for granted maps. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-01-28xen/grant-table: pre-populate kernel unmap ops for xen_gnttab_unmap_refs()David Vrabel
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: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-09-23xen/grant-table: refactor error cleanup in grow_gnttab_list()Chen Gang
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: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-07-14xen/grant-table: remove support for V2 tablesDavid Vrabel
Since 11c7ff17c9b6dbf3a4e4f36be30ad531a6cf0ec9 (xen/grant-table: Force to use v1 of grants.) the code for V2 grant tables is not used. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-07-14x86/xen: safely map and unmap grant frames when in atomic contextDavid Vrabel
arch_gnttab_map_frames() and arch_gnttab_unmap_frames() are called in atomic context but were calling alloc_vm_area() which might sleep. Also, if a driver attempts to allocate a grant ref from an interrupt and the table needs expanding, then the CPU may already by in lazy MMU mode and apply_to_page_range() will BUG when it tries to re-enable lazy MMU mode. These two functions are only used in PV guests. Introduce arch_gnttab_init() to allocates the virtual address space in advance. Avoid the use of apply_to_page_range() by using saving and using the array of PTE addresses from the alloc_vm_area() call. N.B. 'alloc_vm_area' pre-allocates the pagetable so there is no need to worry about having to do a PGD/PUD/PMD walk (like apply_to_page_range does) and we can instead do set_pte. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> ---- [v2: Add comment about alloc_vm_area] [v3: Fix compile error found by 0-day bot]
2014-06-18xen/grant-table: fix suspend for non-PV guestsDavid Vrabel
Commit aa8532c32216ae07c3813b9aeb774517878a7573 (xen: refactor suspend pre/post hooks) broke resuming PVHVM (auto-translated physmap) guests. The gnttab_suspend() would clear the mapping for the grant table frames, but the ->unmap_frames() call is only applicable to PV guests. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-03-18xen/grant-table: Refactor gnttab_[un]map_refs to avoid m2p_overrideZoltan Kiss
The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the bulk of the original function (everything after the mapping hypercall) is moved to arch-dependent set/clear_foreign_p2m_mapping - the "if (xen_feature(XENFEAT_auto_translated_physmap))" branch goes to ARM - therefore the ARM function could be much smaller, the m2p_override stubs could be also removed - on x86 the set_phys_to_machine calls were moved up to this new funcion from m2p_override functions - and m2p_override functions are only called when there is a kmap_ops param It also removes a stray space from arch/x86/include/asm/xen/page.h. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Suggested-by: Anthony Liguori <aliguori@amazon.com> Suggested-by: David Vrabel <david.vrabel@citrix.com> Suggested-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-02-03Revert "xen/grant-table: Avoid m2p_override during mapping"Konrad Rzeszutek Wilk
This reverts commit 08ece5bb2312b4510b161a6ef6682f37f4eac8a1. As it breaks ARM builds and needs more attention on the ARM side. Acked-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-01-31xen/grant-table: Avoid m2p_override during mappingZoltan Kiss
The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the original functions were renamed to __gnttab_[un]map_refs, with a new parameter m2p_override - based on m2p_override either they follow the original behaviour, or just set the private flag and call set_phys_to_machine - gnttab_[un]map_refs are now a wrapper to call __gnttab_[un]map_refs with m2p_override false - a new function gnttab_[un]map_refs_userspace provides the old behaviour It also removes a stray space from page.h and change ret to 0 if XENFEAT_auto_translated_physmap, as that is the only possible return value there. v2: - move the storing of the old mfn in page->index to gnttab_map_refs - move the function header update to a separate patch v3: - a new approach to retain old behaviour where it needed - squash the patches into one v4: - move out the common bits from m2p* functions, and pass pfn/mfn as parameter - clear page->private before doing anything with the page, so m2p_find_override won't race with this v5: - change return value handling in __gnttab_[un]map_refs - remove a stray space in page.h - add detail why ret = 0 now at some places v6: - don't pass pfn to m2p* functions, just get it locally Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Suggested-by: David Vrabel <david.vrabel@citrix.com> Acked-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-01-30xen/gnttab: Use phys_addr_t to describe the grant frame base addressJulien Grall
On ARM, address size can be 32 bits or 64 bits (if CONFIG_ARCH_PHYS_ADDR_T_64BIT is enabled). We can't assume that the grant frame base address will always fits in an unsigned long. Use phys_addr_t instead of unsigned long as argument for gnttab_setup_auto_xlat_frames. Signed-off-by: Julien Grall <julien.grall@linaro.org> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-01-06xen/grant-table: Force to use v1 of grants.Konrad Rzeszutek Wilk
We have the framework to use v2, but there are no backends that actually use it. The end result is that on PV we use v2 grants and on PVHVM v1. The v1 has a capacity of 512 grants per page while the v2 has 256 grants per page. This means we lose about 50% capacity - and if we want more than 16 VIFs (each VIF takes 512 grants), then we are hitting the max per guest of 32. Oracle-bug: 16039922 CC: annie.li@oracle.com CC: msw@amazon.com Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-01-06xen/pvh: Piggyback on PVHVM for grant driver (v4)Konrad Rzeszutek Wilk
In PVH the shared grant frame is the PFN and not MFN, hence its mapped via the same code path as HVM. The allocation of the grant frame is done differently - we do not use the early platform-pci driver and have an ioremap area - instead we use balloon memory and stitch all of the non-contingous pages in a virtualized area. That means when we call the hypervisor to replace the GMFN with a XENMAPSPACE_grant_table type, we need to lookup the old PFN for every iteration instead of assuming a flat contingous PFN allocation. Lastly, we only use v1 for grants. This is because PVHVM is not able to use v2 due to no XENMEM_add_to_physmap calls on the error status page (see commit 69e8f430e243d657c2053f097efebc2e2cd559f0 xen/granttable: Disable grant v2 for HVM domains.) Until that is implemented this workaround has to be in place. Also per suggestions by Stefano utilize the PVHVM paths as they share common functionality. v2 of this patch moves most of the PVH code out in the arch/x86/xen/grant-table driver and touches only minimally the generic driver. v3, v4: fixes us some of the code due to earlier patches. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-01-06xen/grant: Implement an grant frame array struct (v3).Konrad Rzeszutek Wilk
The 'xen_hvm_resume_frames' used to be an 'unsigned long' and contain the virtual address of the grants. That was OK for most architectures (PVHVM, ARM) were the grants are contiguous in memory. That however is not the case for PVH - in which case we will have to do a lookup for each virtual address for the PFN. Instead of doing that, lets make it a structure which will contain the array of PFNs, the virtual address and the count of said PFNs. Also provide a generic functions: gnttab_setup_auto_xlat_frames and gnttab_free_auto_xlat_frames to populate said structure with appropriate values for PVHVM and ARM. To round it off, change the name from 'xen_hvm_resume_frames' to a more descriptive one - 'xen_auto_xlat_grant_frames'. For PVH, in patch "xen/pvh: Piggyback on PVHVM for grant driver" we will populate the 'xen_auto_xlat_grant_frames' by ourselves. v2 moves the xen_remap in the gnttab_setup_auto_xlat_frames and also introduces xen_unmap for gnttab_free_auto_xlat_frames. Suggested-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> [v3: Based on top of 'asm/xen/page.h: remove redundant semicolon'] Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-01-06xen/grant-table: Refactor gnttab_initKonrad Rzeszutek Wilk
We have this odd scenario of where for PV paths we take a shortcut but for the HVM paths we first ioremap xen_hvm_resume_frames, then assign it to gnttab_shared.addr. This is needed because gnttab_map uses gnttab_shared.addr. Instead of having: if (pv) return gnttab_map if (hvm) ... gnttab_map Lets move the HVM part before the gnttab_map and remove the first call to gnttab_map. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2014-01-06xen/grants: Remove gnttab_max_grant_frames dependency on gnttab_init.Konrad Rzeszutek Wilk
The function gnttab_max_grant_frames() returns the maximum amount of frames (pages) of grants we can have. Unfortunatly it was dependent on gnttab_init() having been run before to initialize the boot max value (boot_max_nr_grant_frames). This meant that users of gnttab_max_grant_frames would always get a zero value if they called before gnttab_init() - such as 'platform_pci_init' (drivers/xen/platform-pci.c). Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-12-04XEN: Grant table address, xen_hvm_resume_frames, is a phys_addr not a pfnEric Trudeau
From: Eric Trudeau <etrudeau@broadcom.com> xen_hvm_resume_frames stores the physical address of the grant table. englighten.c was incorrectly setting it as if it was a page frame number. This caused the table to be mapped into the guest at an unexpected physical address. Additionally, a warning is improved to include the grant table address which failed in xen_remap. Signed-off-by: Eric Trudeau <etrudeau@broadcom.com> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-11-26xen/gnttab: leave lazy MMU mode in the case of a m2p override failureMatt Wilson
Commit f62805f1 introduced a bug where lazy MMU mode isn't exited if a m2p_add/remove_override call fails. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Anthony Liguori <aliguori@amazon.com> Cc: xen-devel@lists.xenproject.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Matt Wilson <msw@amazon.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: stable@vger.kernel.org
2013-10-25grant-table: call set_phys_to_machine after mapping grant refsStefano Stabellini
When mapping/unmapping grant refs, call set_phys_to_machine to update the P2M with the new mappings for autotranslate guests. This is (almost) a nop on x86. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Changes in v9: - add in-code comments.
2013-08-09xen-gnt: prevent adding duplicate gnt callbacksRoger Pau Monne
With the current implementation, the callback in the tail of the list can be added twice, because the check done in gnttab_request_free_callback is bogus, callback->next can be NULL if it is the last callback in the list. If we add the same callback twice we end up with an infinite loop, were callback == callback->next. Replace this check with a proper one that iterates over the list to see if the callback has already been added. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Matt Wilson <msw@amazon.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> CC: stable@vger.kernel.org
2013-06-28xen: Convert printks to pr_<level>Joe Perches
Convert printks to pr_<level> (excludes printk(KERN_DEBUG...) to be more consistent throughout the xen subsystem. Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME Coalesce formats and add missing word spaces Add missing newlines Align arguments and reflow to 80 columns Remove DRV_NAME from formats as pr_fmt adds the same content This does change some of the prefixes of these messages but it also does make them more consistent. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-02-19xen: introduce xen_remap, use it instead of ioremapStefano Stabellini
ioremap can't be used to map ring pages on ARM because it uses device memory caching attributes (MT_DEVICE*). Introduce a Xen specific abstraction to map ring pages, called xen_remap, that is defined as ioremap on x86 (no behavioral changes). On ARM it explicitly calls __arm_ioremap with the right caching attributes: MT_MEMORY. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-01-18Merge tag 'stable/for-linus-3.8-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen Pull Xen fixes from Konrad Rzeszutek Wilk: - CVE-2013-0190/XSA-40 (or stack corruption for 32-bit PV kernels) - Fix racy vma access spotted by Al Viro - Fix mmap batch ioctl potentially resulting in large O(n) page allcations. - Fix vcpu online/offline BUG:scheduling while atomic.. - Fix unbound buffer scanning for more than 32 vCPUs. - Fix grant table being incorrectly initialized - Fix incorrect check in pciback - Allow privcmd in backend domains. Fix up whitespace conflict due to ugly merge resolution in Xen tree in arch/arm/xen/enlighten.c * tag 'stable/for-linus-3.8-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: Fix stack corruption in xen_failsafe_callback for 32bit PVOPS guests. Revert "xen/smp: Fix CPU online/offline bug triggering a BUG: scheduling while atomic." xen/gntdev: remove erronous use of copy_to_user xen/gntdev: correctly unmap unlinked maps in mmu notifier xen/gntdev: fix unsafe vma access xen/privcmd: Fix mmap batch ioctl. Xen: properly bound buffer access when parsing cpu/*/availability xen/grant-table: correctly initialize grant table version 1 x86/xen : Fix the wrong check in pciback xen/privcmd: Relax access control in privcmd_ioctl_mmap
2013-01-15xen/grant-table: correctly initialize grant table version 1Matt Wilson
Commit 85ff6acb075a484780b3d763fdf41596d8fc0970 (xen/granttable: Grant tables V2 implementation) changed the GREFS_PER_GRANT_FRAME macro from a constant to a conditional expression. The expression depends on grant_table_version being appropriately set. Unfortunately, at init time grant_table_version will be 0. The GREFS_PER_GRANT_FRAME conditional expression checks for "grant_table_version == 1", and therefore returns the number of grant references per frame for v2. This causes gnttab_init() to allocate fewer pages for gnttab_list, as a frame can old half the number of v2 entries than v1 entries. After gnttab_resume() is called, grant_table_version is appropriately set. nr_init_grefs will then be miscalculated and gnttab_free_count will hold a value larger than the actual number of free gref entries. If a guest is heavily utilizing improperly initialized v1 grant tables, memory corruption can occur. One common manifestation is corruption of the vmalloc list, resulting in a poisoned pointer derefrence when accessing /proc/meminfo or /proc/vmallocinfo: [ 40.770064] BUG: unable to handle kernel paging request at 0000200200001407 [ 40.770083] IP: [<ffffffff811a6fb0>] get_vmalloc_info+0x70/0x110 [ 40.770102] PGD 0 [ 40.770107] Oops: 0000 [#1] SMP [ 40.770114] CPU 10 This patch introduces a static variable, grefs_per_grant_frame, to cache the calculated value. gnttab_init() now calls gnttab_request_version() early so that grant_table_version and grefs_per_grant_frame can be appropriately set. A few BUG_ON()s have been added to prevent this type of bug from reoccurring in the future. Signed-off-by: Matt Wilson <msw@amazon.com> Reviewed-and-Tested-by: Steven Noonan <snoonan@amazon.com> Acked-by: Ian Campbell <Ian.Campbell@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Annie Li <annie.li@oracle.com> Cc: xen-devel@lists.xen.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org # v3.3 and newer Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-01-03Drivers: xen: remove __dev* attributes.Greg Kroah-Hartman
CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, and __devinitdata from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stephen Hemminger <shemminger@vyatta.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Cc: Bill Pemberton <wfp5p@virginia.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-19Merge commit 'v3.7-rc1' into stable/for-linus-3.7Konrad Rzeszutek Wilk
* commit 'v3.7-rc1': (10892 commits) Linux 3.7-rc1 x86, boot: Explicitly include autoconf.h for hostprogs perf: Fix UAPI fallout ARM: config: make sure that platforms are ordered by option string ARM: config: sort select statements alphanumerically UAPI: (Scripted) Disintegrate include/linux/byteorder UAPI: (Scripted) Disintegrate include/linux UAPI: Unexport linux/blk_types.h UAPI: Unexport part of linux/ppp-comp.h perf: Handle new rbtree implementation procfs: don't need a PATH_MAX allocation to hold a string representation of an int vfs: embed struct filename inside of names_cache allocation if possible audit: make audit_inode take struct filename vfs: make path_openat take a struct filename pointer vfs: turn do_path_lookup into wrapper around struct filename variant audit: allow audit code to satisfy getname requests from its names_list vfs: define struct filename and have getname() return it btrfs: Fix compilation with user namespace support enabled userns: Fix posix_acl_file_xattr_userns gid conversion userns: Properly print bluetooth socket uids ...
2012-10-19xen: grant: use xen_pfn_t type for frame_list.Ian Campbell
This correctly sizes it as 64 bit on ARM but leaves it as unsigned long on x86 (therefore no intended change on x86). The long and ulong guest handles are now unused (and a bit dangerous) so remove them. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-02Merge tag 'stable/for-linus-3.7-x86-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen 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. ...
2012-09-21xen/gndev: Xen backend support for paged out grant targets V4.Andres Lagar-Cavilla
Since Xen-4.2, hvm domains may have portions of their memory paged out. When a foreign domain (such as dom0) attempts to map these frames, the map will initially fail. The hypervisor returns a suitable errno, and kicks an asynchronous page-in operation carried out by a helper. The foreign domain is expected to retry the mapping operation until it eventually succeeds. The foreign domain is not put to sleep because itself could be the one running the pager assist (typical scenario for dom0). This patch adds support for this mechanism for backend drivers using grant mapping and copying operations. Specifically, this covers the blkback and gntdev drivers (which map foreign grants), and the netback driver (which copies foreign grants). * Add a retry method for grants that fail with GNTST_eagain (i.e. because the target foreign frame is paged out). * Insert hooks with appropriate wrappers in the aforementioned drivers. The retry loop is only invoked if the grant operation status is GNTST_eagain. It guarantees to leave a new status code different from GNTST_eagain. Any other status code results in identical code execution as before. The retry loop performs 256 attempts with increasing time intervals through a 32 second period. It uses msleep to yield while waiting for the next retry. V2 after feedback from David Vrabel: * Explicit MAX_DELAY instead of wrap-around delay into zero * Abstract GNTST_eagain check into core grant table code for netback module. V3 after feedback from Ian Campbell: * Add placeholder in array of grant table error descriptions for unrelated error code we jump over. * Eliminate single map and retry macro in favor of a generic batch flavor. * Some renaming. * Bury most implementation in grant_table.c, cleaner interface. V4 rebased on top of sync of Xen grant table interface headers. Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org> Acked-by: Ian Campbell <ian.campbell@citrix.com> [v5: Fixed whitespace issues] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-09-12xen/m2p: do not reuse kmap_op->dev_bus_addrStefano Stabellini
If the caller passes a valid kmap_op to m2p_add_override, we use kmap_op->dev_bus_addr to store the original mfn, but dev_bus_addr is part of the interface with Xen and if we are batching the hypercalls it might not have been written by the hypervisor yet. That means that later on Xen will write to it and we'll think that the original mfn is actually what Xen has written to it. Rather than "stealing" struct members from kmap_op, keep using page->index to store the original mfn and add another parameter to m2p_remove_override to get the corresponding kmap_op instead. It is now responsibility of the caller to keep track of which kmap_op corresponds to a particular page in the m2p_override (gntdev, the only user of this interface that passes a valid kmap_op, is already doing that). CC: stable@kernel.org Reported-and-Tested-By: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-08-21xen/apic/xenbus/swiotlb/pcifront/grant/tmem: Make functions or variables static.Konrad Rzeszutek Wilk
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/<some file>.c: warning: symbol '<blah>' 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 <konrad.wilk@oracle.com>