#
37c17856 |
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05-Jan-2023 |
Jiapeng Chong <jiapeng.chong@linux.alibaba.com> |
x86/xen: Remove the unused function p2m_index() The function p2m_index is defined in the p2m.c file, but not called elsewhere, so remove this unused function. arch/x86/xen/p2m.c:137:24: warning: unused function 'p2m_index'. Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3557 Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20230105090141.36248-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Juergen Gross <jgross@suse.com>
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#
4421cca0 |
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05-Nov-2021 |
Mike Rapoport <rppt@kernel.org> |
memblock: use memblock_free for freeing virtual pointers Rename memblock_free_ptr() to memblock_free() and use memblock_free() when freeing a virtual pointer so that memblock_free() will be a counterpart of memblock_alloc() The callers are updated with the below semantic patch and manual addition of (void *) casting to pointers that are represented by unsigned long variables. @@ identifier vaddr; expression size; @@ ( - memblock_phys_free(__pa(vaddr), size); + memblock_free(vaddr, size); | - memblock_free_ptr(vaddr, size); + memblock_free(vaddr, size); ) [sfr@canb.auug.org.au: fixup] Link: https://lkml.kernel.org/r/20211018192940.3d1d532f@canb.auug.org.au Link: https://lkml.kernel.org/r/20210930185031.18648-7-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Juergen Gross <jgross@suse.com> Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
c486514d |
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05-Nov-2021 |
Mike Rapoport <rppt@kernel.org> |
xen/x86: free_p2m_page: use memblock_free_ptr() to free a virtual pointer free_p2m_page() wrongly passes a virtual pointer to memblock_free() that treats it as a physical address. Call memblock_free_ptr() instead that gets a virtual address to free the memory. Link: https://lkml.kernel.org/r/20210930185031.18648-3-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
4b511d5b |
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30-Jul-2021 |
Juergen Gross <jgross@suse.com> |
xen: fix setting of max_pfn in shared_info Xen PV guests are specifying the highest used PFN via the max_pfn field in shared_info. This value is used by the Xen tools when saving or migrating the guest. Unfortunately this field is misnamed, as in reality it is specifying the number of pages (including any memory holes) of the guest, so it is the highest used PFN + 1. Renaming isn't possible, as this is a public Xen hypervisor interface which needs to be kept stable. The kernel will set the value correctly initially at boot time, but when adding more pages (e.g. due to memory hotplug or ballooning) a real PFN number is stored in max_pfn. This is done when expanding the p2m array, and the PFN stored there is even possibly wrong, as it should be the last possible PFN of the just added P2M frame, and not one which led to the P2M expansion. Fix that by setting shared_info->max_pfn to the last possible PFN + 1. Fixes: 98dd166ea3a3c3 ("x86/xen/p2m: hint at the last populated P2M entry") Cc: stable@vger.kernel.org Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Link: https://lore.kernel.org/r/20210730092622.9973-2-jgross@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
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#
af44a387 |
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24-Mar-2021 |
Roger Pau Monne <roger.pau@citrix.com> |
Revert "xen: fix p2m size in dom0 for disabled memory hotplug case" This partially reverts commit 882213990d32 ("xen: fix p2m size in dom0 for disabled memory hotplug case") There's no need to special case XEN_UNPOPULATED_ALLOC anymore in order to correctly size the p2m. The generic memory hotplug option has already been tied together with the Xen hotplug limit, so enabling memory hotplug should already trigger a properly sized p2m on Xen PV. Note that XEN_UNPOPULATED_ALLOC depends on ZONE_DEVICE which pulls in MEMORY_HOTPLUG. Leave the check added to __set_phys_to_machine and the adjusted comment about EXTRA_MEM_RATIO. Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210324122424.58685-3-roger.pau@citrix.com [boris: fixed formatting issues] Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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2b514ec7 |
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24-Mar-2021 |
Roger Pau Monne <roger.pau@citrix.com> |
xen/x86: make XEN_BALLOON_MEMORY_HOTPLUG_LIMIT depend on MEMORY_HOTPLUG The Xen memory hotplug limit should depend on the memory hotplug generic option, rather than the Xen balloon configuration. It's possible to have a kernel with generic memory hotplug enabled, but without Xen balloon enabled, at which point memory hotplug won't work correctly due to the size limitation of the p2m. Rename the option to XEN_MEMORY_HOTPLUG_LIMIT since it's no longer tied to ballooning. Fixes: 9e2369c06c8a18 ("xen: add helpers to allocate unpopulated memory") Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Link: https://lore.kernel.org/r/20210324122424.58685-2-roger.pau@citrix.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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#
bce21a2b |
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10-Mar-2021 |
Jan Beulich <jbeulich@suse.com> |
Xen/gnttab: introduce common INVALID_GRANT_{HANDLE,REF} It's not helpful if every driver has to cook its own. Generalize xenbus'es INVALID_GRANT_HANDLE and pcifront's INVALID_GRANT_REF (which shouldn't have expanded to zero to begin with). Use the constants in p2m.c and gntdev.c right away, and update field types where necessary so they would match with the constants' types (albeit without touching struct ioctl_gntdev_grant_ref's ref field, as that's part of the public interface of the kernel and would require introducing a dependency on Xen's grant_table.h public header). Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/db7c38a5-0d75-d5d1-19de-e5fe9f0b9c48@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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#
0f9b05b9 |
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09-Mar-2021 |
Jan Beulich <jbeulich@suse.com> |
Xen: drop exports of {set,clear}_foreign_p2m_mapping() They're only used internally, and the layering violation they contain (x86) or imply (Arm) of calling HYPERVISOR_grant_table_op() strongly advise against any (uncontrolled) use from a module. The functions also never had users except the ones from drivers/xen/grant-table.c forever since their introduction in 3.15. Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Link: https://lore.kernel.org/r/746a5cd6-1446-eda4-8b23-03c1cac30b8d@suse.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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#
88221399 |
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24-Feb-2021 |
Juergen Gross <jgross@suse.com> |
xen: fix p2m size in dom0 for disabled memory hotplug case Since commit 9e2369c06c8a18 ("xen: add helpers to allocate unpopulated memory") foreign mappings are using guest physical addresses allocated via ZONE_DEVICE functionality. This will result in problems for the case of no balloon memory hotplug being configured, as the p2m list will only cover the initial memory size of the domain. Any ZONE_DEVICE allocated address will be outside the p2m range and thus a mapping can't be established with that memory address. Fix that by extending the p2m size for that case. At the same time add a check for a to be created mapping to be within the p2m limits in order to detect errors early. While changing a comment, remove some 32-bit leftovers. This is XSA-369. Fixes: 9e2369c06c8a18 ("xen: add helpers to allocate unpopulated memory") Cc: <stable@vger.kernel.org> # 5.9 Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
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#
8310b77b |
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25-Feb-2021 |
Jan Beulich <jbeulich@suse.com> |
Xen/gnttab: handle p2m update errors on a per-slot basis Bailing immediately from set_foreign_p2m_mapping() upon a p2m updating error leaves the full batch in an ambiguous state as far as the caller is concerned. Instead flags respective slots as bad, unmapping what was mapped there right away. HYPERVISOR_grant_table_op()'s return value and the individual unmap slots' status fields get used only for a one-time - there's not much we can do in case of a failure. Note that there's no GNTST_enomem or alike, so GNTST_general_error gets used. The map ops' handle fields get overwritten just to be on the safe side. This is part of XSA-367. Cc: <stable@vger.kernel.org> Signed-off-by: Jan Beulich <jbeulich@suse.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/96cccf5d-e756-5f53-b91a-ea269bfb9be0@suse.com Signed-off-by: Juergen Gross <jgross@suse.com>
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#
b512e1b0 |
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15-Feb-2021 |
Jan Beulich <jbeulich@suse.com> |
Xen/x86: also check kernel mapping in set_foreign_p2m_mapping() We should not set up further state if either mapping failed; paying attention to just the user mapping's status isn't enough. Also use GNTST_okay instead of implying its value (zero). This is part of XSA-361. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: stable@vger.kernel.org Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
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#
a35f2ef3 |
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15-Feb-2021 |
Jan Beulich <jbeulich@suse.com> |
Xen/x86: don't bail early from clear_foreign_p2m_mapping() Its sibling (set_foreign_p2m_mapping()) as well as the sibling of its only caller (gnttab_map_refs()) don't clean up after themselves in case of error. Higher level callers are expected to do so. However, in order for that to really clean up any partially set up state, the operation should not terminate upon encountering an entry in unexpected state. It is particularly relevant to notice here that set_foreign_p2m_mapping() would skip setting up a p2m entry if its grant mapping failed, but it would continue to set up further p2m entries as long as their mappings succeeded. Arguably down the road set_foreign_p2m_mapping() may want its page state related WARN_ON() also converted to an error return. This is part of XSA-361. Signed-off-by: Jan Beulich <jbeulich@suse.com> Cc: stable@vger.kernel.org Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
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#
e34ff4cd |
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17-Sep-2020 |
Qinglang Miao <miaoqinglang@huawei.com> |
x86/xen: Convert to DEFINE_SHOW_ATTRIBUTE Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code. Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20200917125547.104472-1-miaoqinglang@huawei.com Signed-off-by: Juergen Gross <jgross@suse.com>
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#
a13f2ef1 |
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29-Jun-2020 |
Juergen Gross <jgross@suse.com> |
x86/xen: remove 32-bit Xen PV guest support Xen is requiring 64-bit machines today and since Xen 4.14 it can be built without 32-bit PV guest support. There is no need to carry the burden of 32-bit PV guest support in the kernel any longer, as new guests can be either HVM or PVH, or they can use a 64 bit kernel. Remove the 32-bit Xen PV support from the kernel. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
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#
ad091376 |
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22-Jan-2019 |
Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
x86: xen: no need to check return value of debugfs_create functions When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <x86@kernel.org> Cc: <xen-devel@lists.xenproject.org> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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#
8a7f97b9 |
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12-Mar-2019 |
Mike Rapoport <rppt@kernel.org> |
treewide: add checks for the return value of memblock_alloc*() Add check for the return value of memblock_alloc*() functions and call panic() in case of error. The panic message repeats the one used by panicing memblock allocators with adjustment of parameters to include only relevant ones. The replacement was mostly automated with semantic patches like the one below with manual massaging of format strings. @@ expression ptr, size, align; @@ ptr = memblock_alloc(size, align); + if (!ptr) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align); [anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type] Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org [rppt@linux.ibm.com: fix format strings for panics after memblock_alloc] Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com [rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails] Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx [akpm@linux-foundation.org: fix xtensa printk warning] Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Reviewed-by: Guo Ren <ren_guo@c-sky.com> [c-sky] Acked-by: Paul Burton <paul.burton@mips.com> [MIPS] Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390] Reviewed-by: Juergen Gross <jgross@suse.com> [Xen] Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k] Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa] Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Christoph Hellwig <hch@lst.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: Dennis Zhou <dennis@kernel.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Mark Salter <msalter@redhat.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Rob Herring <robh+dt@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
1457d8cf |
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07-Nov-2018 |
Juergen Gross <jgross@suse.com> |
x86/xen: fix pv boot Commit 9da3f2b7405440 ("x86/fault: BUG() when uaccess helpers fault on kernel addresses") introduced a regression for booting Xen PV guests. Xen PV guests are using __put_user() and __get_user() for accessing the p2m map (physical to machine frame number map) as accesses might fail in case of not populated areas of the map. With above commit using __put_user() and __get_user() for accessing kernel pages is no longer valid. So replace the Xen hack by adding appropriate p2m access functions using the default fixup handler. Fixes: 9da3f2b7405440 ("x86/fault: BUG() when uaccess helpers fault on kernel addresses") Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com>
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#
57c8a661 |
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30-Oct-2018 |
Mike Rapoport <rppt@linux.vnet.ibm.com> |
mm: remove include/linux/bootmem.h Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
2013288f |
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30-Oct-2018 |
Mike Rapoport <rppt@linux.vnet.ibm.com> |
memblock: replace free_bootmem{_node} with memblock_free The free_bootmem and free_bootmem_node are merely wrappers for memblock_free. Replace their usage with a call to memblock_free using the following semantic patch: @@ expression e1, e2, e3; @@ ( - free_bootmem(e1, e2) + memblock_free(e1, e2) | - free_bootmem_node(e1, e2, e3) + memblock_free(e2, e3) ) Link: http://lkml.kernel.org/r/1536927045-23536-24-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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e0802b8d |
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30-Oct-2018 |
Mike Rapoport <rppt@linux.vnet.ibm.com> |
memblock: replace alloc_bootmem_align with memblock_alloc The functions are equivalent, just the later does not require nobootmem translation layer. Link: http://lkml.kernel.org/r/1536927045-23536-9-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
901d209a |
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28-Aug-2018 |
Juergen Gross <jgross@suse.com> |
x86/xen: Add SPDX identifier in arch/x86/xen files Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: xen-devel@lists.xenproject.org Cc: virtualization@lists.linux-foundation.org Cc: akataria@vmware.com Cc: rusty@rustcorp.com.au Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/20180828074026.820-5-jgross@suse.com
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#
781198f1 |
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07-Feb-2018 |
Simon Gaiser <simon@invisiblethingslab.com> |
xen: Fix {set,clear}_foreign_p2m_mapping on autotranslating guests Commit 82616f9599a7 ("xen: remove tests for pvh mode in pure pv paths") removed the check for autotranslation from {set,clear}_foreign_p2m_mapping but those are called by grant-table.c also on PVH/HVM guests. Cc: <stable@vger.kernel.org> # 4.14 Fixes: 82616f9599a7 ("xen: remove tests for pvh mode in pure pv paths") Signed-off-by: Simon Gaiser <simon@invisiblethingslab.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Juergen Gross <jgross@suse.com>
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#
6aa7de05 |
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23-Oct-2017 |
Mark Rutland <mark.rutland@arm.com> |
locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
82616f95 |
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04-Aug-2017 |
Juergen Gross <jgross@suse.com> |
xen: remove tests for pvh mode in pure pv paths Remove the last tests for XENFEAT_auto_translated_physmap in pure PV-domain specific paths. PVH V1 is gone and the feature will always be "false" in PV guests. 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>
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#
7c0f6ba6 |
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24-Dec-2016 |
Linus Torvalds <torvalds@linux-foundation.org> |
Replace <asm/uaccess.h> with <linux/uaccess.h> globally This was entirely automated, using the script by Al: PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>' sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \ $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h) to do the replacement at the end of the merge window. Requested-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
7a2463dc |
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13-Jul-2016 |
Paul Gortmaker <paul.gortmaker@windriver.com> |
x86/xen: Audit and remove any unnecessary uses of module.h Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance for the presence of either and replace as needed. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20160714001901.31603-7-paul.gortmaker@windriver.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
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#
32d6bd90 |
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24-Jun-2016 |
Michal Hocko <mhocko@suse.com> |
tree wide: get rid of __GFP_REPEAT for order-0 allocations part I This is the third version of the patchset previously sent [1]. I have basically only rebased it on top of 4.7-rc1 tree and dropped "dm: get rid of superfluous gfp flags" which went through dm tree. I am sending it now because it is tree wide and chances for conflicts are reduced considerably when we want to target rc2. I plan to send the next step and rename the flag and move to a better semantic later during this release cycle so we will have a new semantic ready for 4.8 merge window hopefully. Motivation: While working on something unrelated I've checked the current usage of __GFP_REPEAT in the tree. It seems that a majority of the usage is and always has been bogus because __GFP_REPEAT has always been about costly high order allocations while we are using it for order-0 or very small orders very often. It seems that a big pile of them is just a copy&paste when a code has been adopted from one arch to another. I think it makes some sense to get rid of them because they are just making the semantic more unclear. Please note that GFP_REPEAT is documented as * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt * _might_ fail. This depends upon the particular VM implementation. while !costly requests have basically nofail semantic. So one could reasonably expect that order-0 request with __GFP_REPEAT will not loop for ever. This is not implemented right now though. I would like to move on with __GFP_REPEAT and define a better semantic for it. $ git grep __GFP_REPEAT origin/master | wc -l 111 $ git grep __GFP_REPEAT | wc -l 36 So we are down to the third after this patch series. The remaining places really seem to be relying on __GFP_REPEAT due to large allocation requests. This still needs some double checking which I will do later after all the simple ones are sorted out. I am touching a lot of arch specific code here and I hope I got it right but as a matter of fact I even didn't compile test for some archs as I do not have cross compiler for them. Patches should be quite trivial to review for stupid compile mistakes though. The tricky parts are usually hidden by macro definitions and thats where I would appreciate help from arch maintainers. [1] http://lkml.kernel.org/r/1461849846-27209-1-git-send-email-mhocko@kernel.org This patch (of 19): __GFP_REPEAT has a rather weak semantic but since it has been introduced around 2.6.12 it has been ignored for low order allocations. Yet we have the full kernel tree with its usage for apparently order-0 allocations. This is really confusing because __GFP_REPEAT is explicitly documented to allow allocation failures which is a weaker semantic than the current order-0 has (basically nofail). Let's simply drop __GFP_REPEAT from those places. This would allow to identify place which really need allocator to retry harder and formulate a more specific semantic for what the flag is supposed to do actually. Link: http://lkml.kernel.org/r/1464599699-30131-2-git-send-email-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Liqin <liqin.linux@gmail.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> [for tile] Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: John Crispin <blogic@openwrt.org> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: Ley Foon Tan <lftan@altera.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
8edfcf88 |
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22-Jul-2015 |
David Vrabel <david.vrabel@citrix.com> |
x86/xen: export xen_alloc_p2m_entry() Rename alloc_p2m() to xen_alloc_p2m_entry() and export it. This is useful for ensuring that a p2m entry is allocated (i.e., not a shared missing or identity entry) so that subsequent set_phys_to_machine() calls will require no further allocations. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> --- v3: - Make xen_alloc_p2m_entry() a nop on auto-xlate guests.
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#
98dd166e |
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07-Sep-2015 |
David Vrabel <david.vrabel@citrix.com> |
x86/xen/p2m: hint at the last populated P2M entry With commit 633d6f17cd91ad5bf2370265946f716e42d388c6 (x86/xen: prepare p2m list for memory hotplug) the P2M may be sized to accomdate a much larger amount of memory than the domain currently has. When saving a domain, the toolstack must scan all the P2M looking for populated pages. This results in a performance regression due to the unnecessary scanning. Instead of reporting (via shared_info) the maximum possible size of the P2M, hint at the last PFN which might be populated. This hint is increased as new leaves are added to the P2M (in the expectation that they will be used for populated entries). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: <stable@vger.kernel.org> # 4.0+
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#
cb3eb850 |
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16-Jul-2015 |
Juergen Gross <jgross@suse.com> |
xen: remove no longer needed p2m.h Cleanup by removing arch/x86/xen/p2m.h as it isn't needed any more. Most definitions in this file are used in p2m.c only. Move those into p2m.c. set_phys_range_identity() is already declared in arch/x86/include/asm/xen/page.h, add __init annotation there. MAX_REMAP_RANGES isn't used at all, just delete it. The only define left is P2M_PER_PAGE which is moved to page.h as well. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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#
c70727a5 |
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16-Jul-2015 |
Juergen Gross <jgross@suse.com> |
xen: allow more than 512 GB of RAM for 64 bit pv-domains 64 bit pv-domains under Xen are limited to 512 GB of RAM today. The main reason has been the 3 level p2m tree, which was replaced by the virtual mapped linear p2m list. Parallel to the p2m list which is being used by the kernel itself there is a 3 level mfn tree for usage by the Xen tools and eventually for crash dump analysis. For this tree the linear p2m list can serve as a replacement, too. As the kernel can't know whether the tools are capable of dealing with the p2m list instead of the mfn tree, the limit of 512 GB can't be dropped in all cases. This patch replaces the hard limit by a kernel parameter which tells the kernel to obey the 512 GB limit or not. The default is selected by a configuration parameter which specifies whether the 512 GB limit should be active per default for domUs (domain save/restore/migration and crash dump analysis are affected). Memory above the domain limit is returned to the hypervisor instead of being identity mapped, which was wrong anyway. The kernel configuration parameter to specify the maximum size of a domain can be deleted, as it is not relevant any more. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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d51e8b3e |
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16-Jul-2015 |
Juergen Gross <jgross@suse.com> |
xen: don't build mfn tree if tools don't need it In case the Xen tools indicate they don't need the p2m 3 level tree as they support the virtual mapped linear p2m list, just omit building the tree. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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#
4b9c9a11 |
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16-Jul-2015 |
Juergen Gross <jgross@suse.com> |
xen: save linear p2m list address in shared info structure The virtual address of the linear p2m list should be stored in the shared info structure read by the Xen tools to be able to support 64 bit pv-domains larger than 512 GB. Additionally the linear p2m list interface includes a generation count which is changed prior to and after each mapping change of the p2m list. Reading the generation count the Xen tools can detect changes of the mappings and re-read the p2m list eventually. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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#
d6472302 |
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02-Jun-2015 |
Stephen Rothwell <sfr@canb.auug.org.au> |
x86/mm: Decouple <linux/vmalloc.h> from <asm/io.h> Nothing in <asm/io.h> uses anything from <linux/vmalloc.h>, so remove it from there and fix up the resulting build problems triggered on x86 {64|32}-bit {def|allmod|allno}configs. The breakages were triggering in places where x86 builds relied on vmalloc() facilities but did not include <linux/vmalloc.h> explicitly and relied on the implicit inclusion via <asm/io.h>. Also add: - <linux/init.h> to <linux/io.h> - <asm/pgtable_types> to <asm/io.h> ... which were two other implicit header file dependencies. Suggested-by: David Miller <davem@davemloft.net> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> [ Tidied up the changelog. ] Acked-by: David Miller <davem@davemloft.net> Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Vinod Koul <vinod.koul@intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Colin Cross <ccross@android.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: James E.J. Bottomley <JBottomley@odin.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Kees Cook <keescook@chromium.org> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Kristen Carlson Accardi <kristen@linux.intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Suma Ramars <sramars@cisco.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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633d6f17 |
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20-Mar-2015 |
Juergen Gross <jgross@suse.com> |
x86/xen: prepare p2m list for memory hotplug Commit 054954eb051f35e74b75a566a96fe756015352c8 ("xen: switch to linear virtual mapped sparse p2m list") introduced a regression regarding to memory hotplug for a pv-domain: as the virtual space for the p2m list is allocated for the to be expected memory size of the domain only, hotplugged memory above that size will not be usable by the domain. Correct this by using a configurable size for the p2m list in case of memory hotplug enabled (default supported memory size is 512 GB for 64 bit domains and 4 GB for 32 bit domains). Signed-off-by: Juergen Gross <jgross@suse.com> Cc: <stable@vger.kernel.org> # 3.19+ Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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b8f05c88 |
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27-Feb-2015 |
Juergen Gross <jgross@suse.com> |
x86/xen: correct bug in p2m list initialization Commit 054954eb051f35e74b75a566a96fe756015352c8 ("xen: switch to linear virtual mapped sparse p2m list") introduced an error. During initialization of the p2m list a p2m identity area mapped by a complete identity pmd entry has to be split up into smaller chunks sometimes, if a non-identity pfn is introduced in this area. If this non-identity pfn is not at index 0 of a p2m page the new p2m page needed is initialized with wrong identity entries, as the identity pfns don't start with the value corresponding to index 0, but with the initial non-identity pfn. This results in weird wrong mappings. Correct the wrong initialization by starting with the correct pfn. Cc: stable@vger.kernel.org # 3.19 Reported-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Juergen Gross <jgross@suse.com> Tested-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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8da7633f |
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24-Dec-2014 |
Jennifer Herbert <jennifer.herbert@citrix.com> |
xen: mark grant mapped pages as foreign 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>
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0ae65f49 |
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24-Dec-2014 |
Jennifer Herbert <jennifer.herbert@citrix.com> |
x86/xen: require ballooned pages for grant maps Ballooned pages are always used for grant maps which means the original frame does not need to be saved in page->index nor restored after the grant unmap. This allows the workaround in netback for the conflicting use of the (unionized) page->index and page->pfmemalloc to be removed. 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>
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0bb599fd |
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05-Jan-2015 |
David Vrabel <david.vrabel@citrix.com> |
xen: remove scratch frames for ballooned pages and m2p override The scratch frame mappings for ballooned pages and the m2p override are broken. Remove them in preparation for replacing them with simpler mechanisms that works. The scratch pages did not ensure that the page was not in use. In particular, the foreign page could still be in use by hardware. If the guest reused the frame the hardware could read or write that frame. The m2p override did not handle the same frame being granted by two different grant references. Trying an M2P override lookup in this case is impossible. With the m2p override removed, the grant map/unmap for the kernel mappings (for x86 PV) can be easily batched in set_foreign_p2m_mapping() and clear_foreign_p2m_mapping(). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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#
853d0289 |
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05-Jan-2015 |
David Vrabel <david.vrabel@citrix.com> |
xen/grant-table: pre-populate kernel unmap ops for xen_gnttab_unmap_refs() 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>
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#
1760f1eb |
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07-Dec-2014 |
Christian Borntraeger <borntraeger@de.ibm.com> |
x86/xen/p2m: Replace ACCESS_ONCE with READ_ONCE ACCESS_ONCE does not work reliably on non-scalar types. For example gcc 4.6 and 4.7 might remove the volatile tag for such accesses during the SRA (scalar replacement of aggregates) step (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145) Change the p2m code to replace ACCESS_ONCE with READ_ONCE. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Juergen Gross <jgross@suse.com> Acked-by: David Vrabel <david.vrabel@citrix.com>
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#
f241b0b8 |
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11-Jan-2015 |
Juergen Gross <jgross@suse.com> |
xen: correct race in alloc_p2m_pmd() When allocating a new pmd for the linear mapped p2m list a check is done for not introducing another pmd when this just happened on another cpu. In this case the old pte pointer was returned which points to the p2m_missing or p2m_identity page. The correct value would be the pointer to the found new page. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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#
82c92ed1 |
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11-Jan-2015 |
Juergen Gross <jgross@suse.com> |
xen: correct error for building p2m list on 32 bits In xen_rebuild_p2m_list() for large areas of invalid or identity mapped memory the pmd entries on 32 bit systems are initialized wrong. Correct this error. Suggested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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#
701a261a |
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07-Jan-2015 |
Boris Ostrovsky <boris.ostrovsky@oracle.com> |
x86/xen: Free bootmem in free_p2m_page() during early boot With recent changes in p2m we now have legitimate cases when p2m memory needs to be freed during early boot (i.e. before slab is initialized). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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90fff3ea |
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05-Dec-2014 |
Juergen Gross <jgross@suse.com> |
xen: introduce helper functions to do safe read and write accesses Introduce two helper functions to safely read and write unsigned long values from or to memory when the access may fault because the mapping is non-present or read-only. These helpers can be used instead of open coded uses of __get_user() and __put_user() avoiding the need to do casts to fix sparse warnings. Use the helpers in page.h and p2m.c. This will fix the sparse warnings when doing "make C=1". Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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2e917175 |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: Speed up set_phys_to_machine() by using read-only mappings Instead of checking at each call of set_phys_to_machine() whether a new p2m page has to be allocated due to writing an entry in a large invalid or identity area, just map those areas read only and react to a page fault on write by allocating the new page. This change will make the common path with no allocation much faster as it only requires a single write of the new mfn instead of walking the address translation tables and checking for the special cases. Suggested-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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054954eb |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: switch to linear virtual mapped sparse p2m list At start of the day the Xen hypervisor presents a contiguous mfn list to a pv-domain. In order to support sparse memory this mfn list is accessed via a three level p2m tree built early in the boot process. Whenever the system needs the mfn associated with a pfn this tree is used to find the mfn. Instead of using a software walked tree for accessing a specific mfn list entry this patch is creating a virtual address area for the entire possible mfn list including memory holes. The holes are covered by mapping a pre-defined page consisting only of "invalid mfn" entries. Access to a mfn entry is possible by just using the virtual base address of the mfn list and the pfn as index into that list. This speeds up the (hot) path of determining the mfn of a pfn. Kernel build on a Dell Latitude E6440 (2 cores, HT) in 64 bit Dom0 showed following improvements: Elapsed time: 32:50 -> 32:35 System: 18:07 -> 17:47 User: 104:00 -> 103:30 Tested with following configurations: - 64 bit dom0, 8GB RAM - 64 bit dom0, 128 GB RAM, PCI-area above 4 GB - 32 bit domU, 512 MB, 8 GB, 43 GB (more wouldn't work even without the patch) - 32 bit domU, ballooning up and down - 32 bit domU, save and restore - 32 bit domU with PCI passthrough - 64 bit domU, 8 GB, 2049 MB, 5000 MB - 64 bit domU, ballooning up and down - 64 bit domU, save and restore - 64 bit domU with PCI passthrough Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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0aad5689 |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: Hide get_phys_to_machine() to be able to tune common path Today get_phys_to_machine() is always called when the mfn for a pfn is to be obtained. Add a wrapper __pfn_to_mfn() as inline function to be able to avoid calling get_phys_to_machine() when possible as soon as the switch to a linear mapped p2m list has been done. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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5b8e7d80 |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: Delay invalidating extra memory When the physical memory configuration is initialized the p2m entries for not pouplated memory pages are set to "invalid". As those pages are beyond the hypervisor built p2m list the p2m tree has to be extended. This patch delays processing the extra memory related p2m entries during the boot process until some more basic memory management functions are callable. This removes the need to create new p2m entries until virtual memory management is available. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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97f4533a |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: Delay m2p_override initialization The m2p overrides are used to be able to find the local pfn for a foreign mfn mapped into the domain. They are used by driver backends having to access frontend data. As this functionality isn't used in early boot it makes no sense to initialize the m2p override functions very early. It can be done later without doing any harm, removing the need for allocating memory via extend_brk(). While at it make some m2p override functions static as they are only used internally. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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1f3ac86b |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: Delay remapping memory of pv-domain Early in the boot process the memory layout of a pv-domain is changed to match the E820 map (either the host one for Dom0 or the Xen one) regarding placement of RAM and PCI holes. This requires removing memory pages initially located at positions not suitable for RAM and adding them later at higher addresses where no restrictions apply. To be able to operate on the hypervisor supported p2m list until a virtual mapped linear p2m list can be constructed, remapping must be delayed until virtual memory management is initialized, as the initial p2m list can't be extended unlimited at physical memory initialization time due to it's fixed structure. A further advantage is the reduction in complexity and code volume as we don't have to be careful regarding memory restrictions during p2m updates. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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7108c9ce |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: use common page allocation function in p2m.c In arch/x86/xen/p2m.c three different allocation functions for obtaining a memory page are used: extend_brk(), alloc_bootmem_align() or __get_free_page(). Which of those functions is used depends on the progress of the boot process of the system. Introduce a common allocation routine selecting the to be called allocation routine dynamically based on the boot progress. This allows moving initialization steps without having to care about changing allocation calls. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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820c4db2 |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: Make functions static Some functions in arch/x86/xen/p2m.c are used locally only. Make them static. Rearrange the functions in p2m.c to avoid forward declarations. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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6f58d89e |
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28-Nov-2014 |
Juergen Gross <jgross@suse.com> |
xen: fix some style issues in p2m.c The source arch/x86/xen/p2m.c has some coding style issues. Fix them. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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3a0e94f8 |
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17-Oct-2014 |
Juergen Gross <jgross@suse.com> |
x86/xen: avoid race in p2m handling When a new p2m leaf is allocated this leaf is linked into the p2m tree via cmpxchg. Unfortunately the compare value for checking the success of the update is read after checking for the need of a new leaf. It is possible that a new leaf has been linked into the tree concurrently in between. This could lead to a leaked memory page and to the loss of some p2m entries. Avoid the race by using the read compare value for checking the need of a new p2m leaf and use ACCESS_ONCE() to get it. There are other places which seem to need ACCESS_ONCE() to ensure proper operation. Change them accordingly. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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2c185687 |
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14-Oct-2014 |
Juergen Gross <jgross@suse.com> |
x86/xen: delay construction of mfn_list_list The 3 level p2m tree for the Xen tools is constructed very early at boot by calling xen_build_mfn_list_list(). Memory needed for this tree is allocated via extend_brk(). As this tree (other than the kernel internal p2m tree) is only needed for domain save/restore, live migration and crash dump analysis it doesn't matter whether it is constructed very early or just some milliseconds later when memory allocation is possible by other means. This patch moves the call of xen_build_mfn_list_list() just after calling xen_pagetable_p2m_copy() simplifying this function, too, as it doesn't have to bother with two parallel trees now. The same applies for some other internal functions. While simplifying code, make early_can_reuse_p2m_middle() static and drop the unused second parameter. p2m_mid_identity_mfn can be removed as well, it isn't used either. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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239af7c7 |
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14-Oct-2014 |
Juergen Gross <jgross@suse.com> |
x86/xen: avoid writing to freed memory after race in p2m handling In case a race was detected during allocation of a new p2m tree element in alloc_p2m() the new allocated mid_mfn page is freed without updating the pointer to the found value in the tree. This will result in overwriting the just freed page with the mfn of the p2m leaf. Signed-off-by: Juergen Gross <jgross@suse.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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4fbb67e3 |
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11-Aug-2014 |
Matt Rushton <mvrushton@gmail.com> |
xen/setup: Remap Xen Identity Mapped RAM Instead of ballooning up and down dom0 memory this remaps the existing mfns that were replaced by the identity map. The reason for this is that the existing implementation ballooned memory up and and down which caused dom0 to have discontiguous pages. In some cases this resulted in the use of bounce buffers which reduced network I/O performance significantly. This change will honor the existing order of the pages with the exception of some boundary conditions. To do this we need to update both the Linux p2m table and the Xen m2p table. Particular care must be taken when updating the p2m table since it's important to limit table memory consumption and reuse the existing leaf pages which get freed when an entire leaf page is set to the identity map. To implement this, mapping updates are grouped into blocks with table entries getting cached temporarily and then released. On my test system before: Total pages: 2105014 Total contiguous: 1640635 After: Total pages: 2105014 Total contiguous: 2098904 Signed-off-by: Matthew Rushton <mrushton@amazon.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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3fbdf631 |
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19-Jul-2014 |
Matt Rushton <mvrushton@gmail.com> |
xen/setup: Remove Identity Map Debug Message Removing a debug message for setting the identity map since it becomes rather noisy after rework of the identity map code. Signed-off-by: Matthew Rushton <mrushton@amazon.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com>
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25b884a8 |
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03-Jan-2014 |
David Vrabel <david.vrabel@citrix.com> |
x86/xen: set regions above the end of RAM as 1:1 PCI devices may have BARs located above the end of RAM so mark such frames as identity frames in the p2m (instead of the default of missing). PFNs outside the p2m (above MAX_P2M_PFN) are also considered to be identity frames for the same reason. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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3cb83e46 |
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07-Jan-2014 |
David Vrabel <david.vrabel@citrix.com> |
x86/xen: compactly store large identity ranges in the p2m Large (multi-GB) identity ranges currently require a unique middle page (filled with p2m_identity entries) per 1 GB region. Similar to the common p2m_mid_missing middle page for large missing regions, introduce a p2m_mid_identity page (filled with p2m_identity entries) which can be used instead. set_phys_range_identity() thus only needs to allocate new middle pages at the beginning and end of the range. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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a9b5bff6 |
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06-Jan-2014 |
David Vrabel <david.vrabel@citrix.com> |
x86/xen: fix set_phys_range_identity() if pfn_e > MAX_P2M_PFN Allow set_phys_range_identity() to work with a range that overlaps MAX_P2M_PFN by clamping pfn_e to MAX_P2M_PFN. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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fcca2e31 |
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07-Jan-2014 |
David Vrabel <david.vrabel@citrix.com> |
x86/xen: rename early_p2m_alloc() and early_p2m_alloc_middle() early_p2m_alloc_middle() allocates a new leaf page and early_p2m_alloc() allocates a new middle page. This is confusing. Swap the names so they match what the functions actually do. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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1429d46d |
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27-Feb-2014 |
Zoltan Kiss <zoltan.kiss@citrix.com> |
xen/grant-table: Refactor gnttab_[un]map_refs to avoid m2p_override 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>
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e85fc980 |
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03-Feb-2014 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
Revert "xen/grant-table: Avoid m2p_override during mapping" 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>
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08ece5bb |
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23-Jan-2014 |
Zoltan Kiss <zoltan.kiss@citrix.com> |
xen/grant-table: Avoid m2p_override during mapping 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>
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4dd322bc |
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31-Dec-2013 |
Mukesh Rathor <mukesh.rathor@oracle.com> |
xen/pvh: Setup up shared_info. For PVHVM the shared_info structure is provided via the same way as for normal PV guests (see include/xen/interface/xen.h). That is during bootup we get 'xen_start_info' via the %esi register in startup_xen. Then later we extract the 'shared_info' from said structure (in xen_setup_shared_info) and start using it. The 'xen_setup_shared_info' is all setup to work with auto-xlat guests, but there are two functions which it calls that are not: xen_setup_mfn_list_list and xen_setup_vcpu_info_placement. This patch modifies the P2M code (xen_setup_mfn_list_list) while the "Piggyback on PVHVM for event channels" modifies the xen_setup_vcpu_info_placement. Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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696fd7c5 |
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14-Dec-2013 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/pvh: Don't setup P2M tree. P2M is not available for PVH. Fortunatly for us the P2M code already has mostly the support for auto-xlat guest thanks to commit 3d24bbd7dddbea54358a9795abaf051b0f18973c "grant-table: call set_phys_to_machine after mapping grant refs" which: " introduces set_phys_to_machine calls for auto_translated guests (even on x86) in gnttab_map_refs and gnttab_unmap_refs. translated by swiotlb-xen... " so we don't need to muck much. with above mentioned "commit you'll get set_phys_to_machine calls from gnttab_map_refs and gnttab_unmap_refs but PVH guests won't do anything with them " (Stefano Stabellini) which is OK - we want them to be NOPs. This is because we assume that an "IOMMU is always present on the plaform and Xen is going to make the appropriate IOMMU pagetable changes in the hypercall implementation of GNTTABOP_map_grant_ref and GNTTABOP_unmap_grant_ref, then eveything should be transparent from PVH priviligied point of view and DMA transfers involving foreign pages keep working with no issues[sp] Otherwise we would need a P2M (and an M2P) for PVH priviligied to track these foreign pages .. (see arch/arm/xen/p2m.c)." (Stefano Stabellini). We still have to inhibit the building of the P2M tree. That had been done in the past by not calling xen_build_dynamic_phys_to_machine (which setups the P2M tree and gives us virtual address to access them). But we are missing a check for xen_build_mfn_list_list - which was continuing to setup the P2M tree and would blow up at trying to get the virtual address of p2m_missing (which would have been setup by xen_build_dynamic_phys_to_machine). Hence a check is needed to not call xen_build_mfn_list_list when running in auto-xlat mode. Instead of replicating the check for auto-xlat in enlighten.c do it in the p2m.c code. The reason is that the xen_build_mfn_list_list is called also in xen_arch_post_suspend without any checks for auto-xlat. So for PVH or PV with auto-xlat - we would needlessly allocate space for an P2M tree. 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>
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2f558d40 |
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09-Oct-2013 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen/x86: allow __set_phys_to_machine for autotranslate guests Allow __set_phys_to_machine to be called for autotranslate guests. It can be used to keep track of phys_to_machine changes, however we don't do anything with the information at the moment. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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0160676b |
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13-Sep-2013 |
David Vrabel <david.vrabel@citrix.com> |
xen/p2m: check MFN is in range before using the m2p table On hosts with more than 168 GB of memory, a 32-bit guest may attempt to grant map an MFN that is error cannot lookup in its mapping of the m2p table. There is an m2p lookup as part of m2p_add_override() and m2p_remove_override(). The lookup falls off the end of the mapped portion of the m2p and (because the mapping is at the highest virtual address) wraps around and the lookup causes a fault on what appears to be a user space address. do_page_fault() (thinking it's a fault to a userspace address), tries to lock mm->mmap_sem. If the gntdev device is used for the grant map, m2p_add_override() is called from from gnttab_mmap() with mm->mmap_sem already locked. do_page_fault() then deadlocks. The deadlock would most commonly occur when a 64-bit guest is started and xenconsoled attempts to grant map its console ring. Introduce mfn_to_pfn_no_overrides() which checks the MFN is within the mapped portion of the m2p table before accessing the table and use this in m2p_add_override(), m2p_remove_override(), and mfn_to_pfn() (which already had the correct range check). All faults caused by accessing the non-existant parts of the m2p are thus within the kernel address space and exception_fixup() is called without trying to lock mm->mmap_sem. This means that for MFNs that are outside the mapped range of the m2p then mfn_to_pfn() will always look in the m2p overrides. This is correct because it must be a foreign MFN (and the PFN in the m2p in this case is only relevant for the other domain). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Stefano Stabellini <stefano.stabellini@citrix.com> Cc: Jan Beulich <JBeulich@suse.com> -- v3: check for auto_translated_physmap in mfn_to_pfn_no_overrides() v2: in mfn_to_pfn() look in m2p_overrides if the MFN is out of range as it's probably foreign. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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d7f8f48d |
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09-Sep-2013 |
Boris Ostrovsky <boris.ostrovsky@oracle.com> |
xen/p2m: Don't call get_balloon_scratch_page() twice, keep interrupts disabled for multicalls m2p_remove_override() calls get_balloon_scratch_page() in MULTI_update_va_mapping() even though it already has pointer to this page from the earlier call (in scratch_page). This second call doesn't have a matching put_balloon_scratch_page() thus not restoring preempt count back. (Also, there is no put_balloon_scratch_page() in the error path.) In addition, the second multicall uses __xen_mc_entry() which does not disable interrupts. Rearrange xen_mc_* calls to keep interrupts off while performing multicalls. This commit fixes a regression introduced by: commit ee0726407feaf504dff304fb603652fb2d778b42 Author: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Date: Tue Jul 23 17:23:54 2013 +0000 xen/m2p: use GNTTABOP_unmap_and_replace to reinstate the original mapping Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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ee072640 |
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23-Jul-2013 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen/m2p: use GNTTABOP_unmap_and_replace to reinstate the original mapping GNTTABOP_unmap_grant_ref unmaps a grant and replaces it with a 0 mapping instead of reinstating the original mapping. Doing so separately would be racy. To unmap a grant and reinstate the original mapping atomically we use GNTTABOP_unmap_and_replace. GNTTABOP_unmap_and_replace doesn't work with GNTMAP_contains_pte, so don't use it for kmaps. GNTTABOP_unmap_and_replace zeroes the mapping passed in new_addr so we have to reinstate it, however that is a per-cpu mapping only used for balloon scratch pages, so we can be sure that it's not going to be accessed while the mapping is not valid. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> CC: alex@alex.org.uk CC: dcrisan@flexiant.com [v1: Konrad fixed up the conflicts] Conflicts: arch/x86/xen/p2m.c
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65a45fa2 |
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19-Jul-2013 |
David Vrabel <david.vrabel@citrix.com> |
xen/p2m: avoid unneccesary TLB flush in m2p_remove_override() In m2p_remove_override() when removing the grant map from the kernel mapping and replacing with a mapping to the original page, the grant unmap will already have flushed the TLB and it is not necessary to do it again after updating the mapping. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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2fc136ee |
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11-Sep-2012 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen/m2p: do not reuse kmap_op->dev_bus_addr 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>
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50e90041 |
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04-Sep-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Fix one-off error in checking the P2M tree directory. We would traverse the full P2M top directory (from 0->MAX_DOMAIN_PAGES inclusive) when trying to figure out whether we can re-use some of the P2M middle leafs. Which meant that if the kernel was compiled with MAX_DOMAIN_PAGES=512 we would try to use the 512th entry. Fortunately for us the p2m_top_index has a check for this: BUG_ON(pfn >= MAX_P2M_PFN); which we hit and saw this: (XEN) domain_crash_sync called from entry.S (XEN) Domain 0 (vcpu#0) crashed on cpu#0: (XEN) ----[ Xen-4.1.2-OVM x86_64 debug=n Tainted: C ]---- (XEN) CPU: 0 (XEN) RIP: e033:[<ffffffff819cadeb>] (XEN) RFLAGS: 0000000000000212 EM: 1 CONTEXT: pv guest (XEN) rax: ffffffff81db5000 rbx: ffffffff81db4000 rcx: 0000000000000000 (XEN) rdx: 0000000000480211 rsi: 0000000000000000 rdi: ffffffff81db4000 (XEN) rbp: ffffffff81793db8 rsp: ffffffff81793d38 r8: 0000000008000000 (XEN) r9: 4000000000000000 r10: 0000000000000000 r11: ffffffff81db7000 (XEN) r12: 0000000000000ff8 r13: ffffffff81df1ff8 r14: ffffffff81db6000 (XEN) r15: 0000000000000ff8 cr0: 000000008005003b cr4: 00000000000026f0 (XEN) cr3: 0000000661795000 cr2: 0000000000000000 Fixes-Oracle-Bug: 14570662 CC: stable@vger.kernel.org # only for v3.5 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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3fc509fc |
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16-Aug-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: When revectoring deal with holes in the P2M array. When we free the PFNs and then subsequently populate them back during bootup: Freeing 20000-20200 pfn range: 512 pages freed 1-1 mapping on 20000->20200 Freeing 40000-40200 pfn range: 512 pages freed 1-1 mapping on 40000->40200 Freeing bad80-badf4 pfn range: 116 pages freed 1-1 mapping on bad80->badf4 Freeing badf6-bae7f pfn range: 137 pages freed 1-1 mapping on badf6->bae7f Freeing bb000-100000 pfn range: 282624 pages freed 1-1 mapping on bb000->100000 Released 283999 pages of unused memory Set 283999 page(s) to 1-1 mapping Populating 1acb8a-1f20e9 pfn range: 283999 pages added We end up having the P2M array (that is the one that was grafted on the P2M tree) filled with IDENTITY_FRAME or INVALID_P2M_ENTRY) entries. The patch titled "xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID." recycles said slots and replaces the P2M tree leaf's with &mfn_list[xx] with p2m_identity or p2m_missing. And re-uses the P2M array sections for other P2M tree leaf's. For the above mentioned bootup excerpt, the PFNs at 0x20000->0x20200 are going to be IDENTITY based: P2M[0][256][0] -> P2M[0][257][0] get turned in IDENTITY_FRAME. We can re-use that and replace P2M[0][256] to point to p2m_identity. The "old" page (the grafted P2M array provided by Xen) that was at P2M[0][256] gets put somewhere else. Specifically at P2M[6][358], b/c when we populate back: Populating 1acb8a-1f20e9 pfn range: 283999 pages added we fill P2M[6][358][0] (and P2M[6][358], P2M[6][359], ...) with the new MFNs. That is all OK, except when we revector we assume that the PFN count would be the same in the grafted P2M array and in the newly allocated. Since that is no longer the case, as we have holes in the P2M that point to p2m_missing or p2m_identity we have to take that into account. [v2: Check for overflow] [v3: Move within the __va check] [v4: Fix the computation] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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357a3cfb |
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19-Jul-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Add logic to revector a P2M tree to use __va leafs. During bootup Xen supplies us with a P2M array. It sticks it right after the ramdisk, as can be seen with a 128GB PV guest: (certain parts removed for clarity): xc_dom_build_image: called xc_dom_alloc_segment: kernel : 0xffffffff81000000 -> 0xffffffff81e43000 (pfn 0x1000 + 0xe43 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x1000+0xe43 at 0x7f097d8bf000 xc_dom_alloc_segment: ramdisk : 0xffffffff81e43000 -> 0xffffffff925c7000 (pfn 0x1e43 + 0x10784 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x1e43+0x10784 at 0x7f0952dd2000 xc_dom_alloc_segment: phys2mach : 0xffffffff925c7000 -> 0xffffffffa25c7000 (pfn 0x125c7 + 0x10000 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x125c7+0x10000 at 0x7f0942dd2000 xc_dom_alloc_page : start info : 0xffffffffa25c7000 (pfn 0x225c7) xc_dom_alloc_page : xenstore : 0xffffffffa25c8000 (pfn 0x225c8) xc_dom_alloc_page : console : 0xffffffffa25c9000 (pfn 0x225c9) nr_page_tables: 0x0000ffffffffffff/48: 0xffff000000000000 -> 0xffffffffffffffff, 1 table(s) nr_page_tables: 0x0000007fffffffff/39: 0xffffff8000000000 -> 0xffffffffffffffff, 1 table(s) nr_page_tables: 0x000000003fffffff/30: 0xffffffff80000000 -> 0xffffffffbfffffff, 1 table(s) nr_page_tables: 0x00000000001fffff/21: 0xffffffff80000000 -> 0xffffffffa27fffff, 276 table(s) xc_dom_alloc_segment: page tables : 0xffffffffa25ca000 -> 0xffffffffa26e1000 (pfn 0x225ca + 0x117 pages) xc_dom_pfn_to_ptr: domU mapping: pfn 0x225ca+0x117 at 0x7f097d7a8000 xc_dom_alloc_page : boot stack : 0xffffffffa26e1000 (pfn 0x226e1) xc_dom_build_image : virt_alloc_end : 0xffffffffa26e2000 xc_dom_build_image : virt_pgtab_end : 0xffffffffa2800000 So the physical memory and virtual (using __START_KERNEL_map addresses) layout looks as so: phys __ka /------------\ /-------------------\ | 0 | empty | 0xffffffff80000000| | .. | | .. | | 16MB | <= kernel starts | 0xffffffff81000000| | .. | | | | 30MB | <= kernel ends => | 0xffffffff81e43000| | .. | & ramdisk starts | .. | | 293MB | <= ramdisk ends=> | 0xffffffff925c7000| | .. | & P2M starts | .. | | .. | | .. | | 549MB | <= P2M ends => | 0xffffffffa25c7000| | .. | start_info | 0xffffffffa25c7000| | .. | xenstore | 0xffffffffa25c8000| | .. | cosole | 0xffffffffa25c9000| | 549MB | <= page tables => | 0xffffffffa25ca000| | .. | | | | 550MB | <= PGT end => | 0xffffffffa26e1000| | .. | boot stack | | \------------/ \-------------------/ As can be seen, the ramdisk, P2M and pagetables are taking a bit of __ka addresses space. Which is a problem since the MODULES_VADDR starts at 0xffffffffa0000000 - and P2M sits right in there! This results during bootup with the inability to load modules, with this error: ------------[ cut here ]------------ WARNING: at /home/konrad/ssd/linux/mm/vmalloc.c:106 vmap_page_range_noflush+0x2d9/0x370() Call Trace: [<ffffffff810719fa>] warn_slowpath_common+0x7a/0xb0 [<ffffffff81030279>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81071a45>] warn_slowpath_null+0x15/0x20 [<ffffffff81130b89>] vmap_page_range_noflush+0x2d9/0x370 [<ffffffff81130c4d>] map_vm_area+0x2d/0x50 [<ffffffff811326d0>] __vmalloc_node_range+0x160/0x250 [<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80 [<ffffffff810c6186>] ? load_module+0x66/0x19c0 [<ffffffff8105cadc>] module_alloc+0x5c/0x60 [<ffffffff810c5369>] ? module_alloc_update_bounds+0x19/0x80 [<ffffffff810c5369>] module_alloc_update_bounds+0x19/0x80 [<ffffffff810c70c3>] load_module+0xfa3/0x19c0 [<ffffffff812491f6>] ? security_file_permission+0x86/0x90 [<ffffffff810c7b3a>] sys_init_module+0x5a/0x220 [<ffffffff815ce339>] system_call_fastpath+0x16/0x1b ---[ end trace fd8f7704fdea0291 ]--- vmalloc: allocation failure, allocated 16384 of 20480 bytes modprobe: page allocation failure: order:0, mode:0xd2 Since the __va and __ka are 1:1 up to MODULES_VADDR and cleanup_highmap rids __ka of the ramdisk mapping, what we want to do is similar - get rid of the P2M in the __ka address space. There are two ways of fixing this: 1) All P2M lookups instead of using the __ka address would use the __va address. This means we can safely erase from __ka space the PMD pointers that point to the PFNs for P2M array and be OK. 2). Allocate a new array, copy the existing P2M into it, revector the P2M tree to use that, and return the old P2M to the memory allocate. This has the advantage that it sets the stage for using XEN_ELF_NOTE_INIT_P2M feature. That feature allows us to set the exact virtual address space we want for the P2M - and allows us to boot as initial domain on large machines. So we pick option 2). This patch only lays the groundwork in the P2M code. The patch that modifies the MMU is called "xen/mmu: Copy and revector the P2M tree." Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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51faaf2b |
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22-Aug-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
Revert "xen/x86: Workaround 64-bit hypervisor and 32-bit initial domain." and "xen/x86: Use memblock_reserve for sensitive areas." This reverts commit 806c312e50f122c47913145cf884f53dd09d9199 and commit 59b294403e9814e7c1154043567f0d71bac7a511. And also documents setup.c and why we want to do it that way, which is that we tried to make the the memblock_reserve more selective so that it would be clear what region is reserved. Sadly we ran in the problem wherein on a 64-bit hypervisor with a 32-bit initial domain, the pt_base has the cr3 value which is not neccessarily where the pagetable starts! As Jan put it: " Actually, the adjustment turns out to be correct: The page tables for a 32-on-64 dom0 get allocated in the order "first L1", "first L2", "first L3", so the offset to the page table base is indeed 2. When reading xen/include/public/xen.h's comment very strictly, this is not a violation (since there nothing is said that the first thing in the page table space is pointed to by pt_base; I admit that this seems to be implied though, namely do I think that it is implied that the page table space is the range [pt_base, pt_base + nt_pt_frames), whereas that range here indeed is [pt_base - 2, pt_base - 2 + nt_pt_frames), which - without a priori knowledge - the kernel would have difficulty to figure out)." - so lets just fall back to the easy way and reserve the whole region. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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59b29440 |
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19-Jul-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/x86: Use memblock_reserve for sensitive areas. instead of a big memblock_reserve. This way we can be more selective in freeing regions (and it also makes it easier to understand where is what). [v1: Move the auto_translate_physmap to proper line] [v2: Per Stefano suggestion add more comments] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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a3118beb |
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28-Jun-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Fix the comment describing the P2M tree. It mixed up the p2m_mid_missing with p2m_missing. Also remove some extra spaces. Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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250a41e0 |
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17-Aug-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Reuse existing P2M leafs if they are filled with 1:1 PFNs or INVALID. If P2M leaf is completly packed with INVALID_P2M_ENTRY or with 1:1 PFNs (so IDENTITY_FRAME type PFNs), we can swap the P2M leaf with either a p2m_missing or p2m_identity respectively. The old page (which was created via extend_brk or was grafted on from the mfn_list) can be re-used for setting new PFNs. This also means we can remove git commit: 5bc6f9888db5739abfa0cae279b4b442e4db8049 xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back which tried to fix this. and make the amount that is required to be reserved much smaller. CC: stable@vger.kernel.org # for 3.5 only. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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5bc6f988 |
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30-Jul-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Reserve 8MB of _brk space for P2M leafs when populating back. When we release pages back during bootup: Freeing 9d-100 pfn range: 99 pages freed Freeing 9cf36-9d0d2 pfn range: 412 pages freed Freeing 9f6bd-9f6bf pfn range: 2 pages freed Freeing 9f714-9f7bf pfn range: 171 pages freed Freeing 9f7e0-9f7ff pfn range: 31 pages freed Freeing 9f800-100000 pfn range: 395264 pages freed Released 395979 pages of unused memory We then try to populate those pages back. In the P2M tree however the space for those leafs must be reserved - as such we use extend_brk. We reserve 8MB of _brk space, which means we can fit over 1048576 PFNs - which is more than we should ever need. Without this, on certain compilation of the kernel we would hit: (XEN) domain_crash_sync called from entry.S (XEN) CPU: 0 (XEN) RIP: e033:[<ffffffff818aad3b>] (XEN) RFLAGS: 0000000000000206 EM: 1 CONTEXT: pv guest (XEN) rax: ffffffff81a7c000 rbx: 000000000000003d rcx: 0000000000001000 (XEN) rdx: ffffffff81a7b000 rsi: 0000000000001000 rdi: 0000000000001000 (XEN) rbp: ffffffff81801cd8 rsp: ffffffff81801c98 r8: 0000000000100000 (XEN) r9: ffffffff81a7a000 r10: 0000000000000001 r11: 0000000000000003 (XEN) r12: 0000000000000004 r13: 0000000000000004 r14: 000000000000003d (XEN) r15: 00000000000001e8 cr0: 000000008005003b cr4: 00000000000006f0 (XEN) cr3: 0000000125803000 cr2: 0000000000000000 (XEN) ds: 0000 es: 0000 fs: 0000 gs: 0000 ss: e02b cs: e033 (XEN) Guest stack trace from rsp=ffffffff81801c98: .. which is extend_brk hitting a BUG_ON. Interestingly enough, most of the time we are not going to hit this b/c the _brk space is quite large (v3.5): ffffffff81a25000 B __brk_base ffffffff81e43000 B __brk_limit = ~4MB. vs earlier kernels (with this back-ported), the space is smaller: ffffffff81a25000 B __brk_base ffffffff81a7b000 B __brk_limit = 344 kBytes. where we would certainly hit this and hit extend_brk. Note that git commit c3d93f880197953f86ab90d9da4744e926b38e33 (xen: populate correct number of pages when across mem boundary (v2)) exposed this bug). [v1: Made it 8MB of _brk space instead of 4MB per Jan's suggestion] CC: stable@vger.kernel.org #only for 3.5 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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b9e0d95c |
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23-May-2012 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen: mark local pages as FOREIGN in the m2p_override When the frontend and the backend reside on the same domain, even if we add pages to the m2p_override, these pages will never be returned by mfn_to_pfn because the check "get_phys_to_machine(pfn) != mfn" will always fail, so the pfn of the frontend will be returned instead (resulting in a deadlock because the frontend pages are already locked). INFO: task qemu-system-i38:1085 blocked for more than 120 seconds. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. qemu-system-i38 D ffff8800cfc137c0 0 1085 1 0x00000000 ffff8800c47ed898 0000000000000282 ffff8800be4596b0 00000000000137c0 ffff8800c47edfd8 ffff8800c47ec010 00000000000137c0 00000000000137c0 ffff8800c47edfd8 00000000000137c0 ffffffff82213020 ffff8800be4596b0 Call Trace: [<ffffffff81101ee0>] ? __lock_page+0x70/0x70 [<ffffffff81a0fdd9>] schedule+0x29/0x70 [<ffffffff81a0fe80>] io_schedule+0x60/0x80 [<ffffffff81101eee>] sleep_on_page+0xe/0x20 [<ffffffff81a0e1ca>] __wait_on_bit_lock+0x5a/0xc0 [<ffffffff81101ed7>] __lock_page+0x67/0x70 [<ffffffff8106f750>] ? autoremove_wake_function+0x40/0x40 [<ffffffff811867e6>] ? bio_add_page+0x36/0x40 [<ffffffff8110b692>] set_page_dirty_lock+0x52/0x60 [<ffffffff81186021>] bio_set_pages_dirty+0x51/0x70 [<ffffffff8118c6b4>] do_blockdev_direct_IO+0xb24/0xeb0 [<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00 [<ffffffff8118ca95>] __blockdev_direct_IO+0x55/0x60 [<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00 [<ffffffff811e91c8>] ext3_direct_IO+0xf8/0x390 [<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00 [<ffffffff81004b60>] ? xen_mc_flush+0xb0/0x1b0 [<ffffffff81104027>] generic_file_aio_read+0x737/0x780 [<ffffffff813bedeb>] ? gnttab_map_refs+0x15b/0x1e0 [<ffffffff811038f0>] ? find_get_pages+0x150/0x150 [<ffffffff8119736c>] aio_rw_vect_retry+0x7c/0x1d0 [<ffffffff811972f0>] ? lookup_ioctx+0x90/0x90 [<ffffffff81198856>] aio_run_iocb+0x66/0x1a0 [<ffffffff811998b8>] do_io_submit+0x708/0xb90 [<ffffffff81199d50>] sys_io_submit+0x10/0x20 [<ffffffff81a18d69>] system_call_fastpath+0x16/0x1b The explanation is in the comment within the code: We need to do this because the pages shared by the frontend (xen-blkfront) can be already locked (lock_page, called by do_read_cache_page); when the userspace backend tries to use them with direct_IO, mfn_to_pfn returns the pfn of the frontend, so do_blockdev_direct_IO is going to try to lock the same pages again resulting in a deadlock. A simplified call graph looks like this: pygrub QEMU ----------------------------------------------- do_read_cache_page io_submit | | lock_page ext3_direct_IO | bio_add_page | lock_page Internally the xen-blkback uses m2p_add_override to swizzle (temporarily) a 'struct page' to have a different MFN (so that it can point to another guest). It also can easily find out whether another pfn corresponding to the mfn exists in the m2p, and can set the FOREIGN bit in the p2m, making sure that mfn_to_pfn returns the pfn of the backend. This allows the backend to perform direct_IO on these pages, but as a side effect prevents the frontend from using get_user_pages_fast on them while they are being shared with the backend. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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3d81acb1 |
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20-Apr-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
Revert "xen/p2m: m2p_find_override: use list_for_each_entry_safe" This reverts commit b960d6c43a63ebd2d8518b328da3816b833ee8cc. If we have another thread (very likely) touched the list, we end up hitting a problem "that the next element is wrong because we should be able to cope with that. The problem is that the next->next pointer would be set LIST_POISON1. " (Stefano's comment on the patch). Reverting for now. Suggested-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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b960d6c4 |
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27-Mar-2012 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen/p2m: m2p_find_override: use list_for_each_entry_safe Use list_for_each_entry_safe and remove the spin_lock acquisition in m2p_find_override. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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940713bb |
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30-Mar-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: An early bootup variant of set_phys_to_machine During early bootup we can't use alloc_page, so to allocate leaf pages in the P2M we need to use extend_brk. For that we are utilizing the early_alloc_p2m and early_alloc_p2m_middle functions to do the job for us. This function follows the same logic as set_phys_to_machine. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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d5096850 |
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30-Mar-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Collapse early_alloc_p2m_middle redundant checks. At the start of the function we were checking for idx != 0 and bailing out. And later calling extend_brk if idx != 0. That is unnecessary so remove that checks. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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cef4cca5 |
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30-Mar-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument For identity cases we want to call reserve_brk only on the boundary conditions of the middle P2M (so P2M[x][y][0] = extend_brk). This is to work around identify regions (PCI spaces, gaps in E820) which are not aligned on 2MB regions. However for the case were we want to allocate P2M middle leafs at the early bootup stage, irregardless of this alignment check we need some means of doing that. For that we provide the new argument. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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3f3aaea2 |
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30-Mar-2012 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Move code around to allow for better re-usage. We are going to be using the early_alloc_p2m (and early_alloc_p2m_middle) code in follow up patches which are not related to setting identity pages. Hence lets move the code out in its own function and rename them as appropiate. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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a491dbef |
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02-Oct-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m/debugfs: Make type_name more obvious. Per Ian Campbell suggestion to defend against future breakage in case we expand the P2M values, incorporate the defines in the string array. Suggested-by: Ian Campbell <Ian.Campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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8404877e |
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29-Sep-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m/debugfs: Fix potential pointer exception. We could be referencing the last + 1 element of level_name[] array which would cause a pointer exception, because of the initial setup of lvl=4. [v1: No need to do this for type_name, pointed out by Ian Campbell] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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0930bba6 |
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29-Sep-2011 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen: modify kernel mappings corresponding to granted pages If we want to use granted pages for AIO, changing the mappings of a user vma and the corresponding p2m is not enough, we also need to update the kernel mappings accordingly. Currently this is only needed for pages that are created for user usages through /dev/xen/gntdev. As in, pages that have been in use by the kernel and use the P2M will not need this special mapping. However there are no guarantees that in the future the kernel won't start accessing pages through the 1:1 even for internal usage. In order to avoid the complexity of dealing with highmem, we allocated the pages lowmem. We issue a HYPERVISOR_grant_table_op right away in m2p_add_override and we remove the mappings using another HYPERVISOR_grant_table_op in m2p_remove_override. Considering that m2p_add_override and m2p_remove_override are called once per page we use multicalls and hypercall batching. Use the kmap_op pointer directly as argument to do the mapping as it is guaranteed to be present up until the unmapping is done. Before issuing any unmapping multicalls, we need to make sure that the mapping has already being done, because we need the kmap->handle to be set correctly. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> [v1: Removed GRANT_FRAME_BIT usage] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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0f4b49ea |
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23-Sep-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Use SetPagePrivate and its friends for M2P overrides. We use the page->private field and hence should use the proper macros and set proper bits. Also WARN_ON in case somebody tries to overwrite our data. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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a867db10 |
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23-Sep-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Make debug/xen/mmu/p2m visible again. We dropped a lot of the MMU debugfs in favour of using tracing API - but there is one which just provides mostly static information that was made invisible by this change. Bring it back. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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c9ce9e43 |
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20-Apr-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Add EXPORT_SYMBOL_GPL to the M2P override functions. If the backends, which use these two functions, are compiled as a module we need these two functions to be exported. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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d5431d52 |
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28-Feb-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m/m2p/gnttab: Support GNTMAP_host_map in the M2P override. We only supported the M2P (and P2M) override only for the GNTMAP_contains_pte type mappings. Meaning that we grants operations would "contain the machine address of the PTE to update" If the flag is unset, then the grant operation is "contains a host virtual address". The latter case means that the Hypervisor takes care of updating our page table (specifically the PTE entry) with the guest's MFN. As such we should not try to do anything with the PTE. Previous to this patch we would try to clear the PTE which resulted in Xen hypervisor being upset with us: (XEN) mm.c:1066:d0 Attempt to implicitly unmap a granted PTE c0100000ccc59067 (XEN) domain_crash called from mm.c:1067 (XEN) Domain 0 (vcpu#0) crashed on cpu#3: (XEN) ----[ Xen-4.0-110228 x86_64 debug=y Not tainted ]---- and crashing us. This patch allows us to inhibit the PTE clearing in the PV guest if the GNTMAP_contains_pte is not set. On the m2p_remove_override path we provide the same parameter. Sadly in the grant-table driver we do not have a mechanism to tell m2p_remove_override whether to clear the PTE or not. Since the grant-table driver is used by user-space, we can safely assume that it operates only on PTE's. Hence the implementation for it to work on !GNTMAP_contains_pte returns -EOPNOTSUPP. In the future we can implement the support for this. It will require some extra accounting structure to keep track of the page[i], and the flag. [v1: Added documentation details, made it return -EOPNOTSUPP instead of trying to do a half-way implementation] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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8c595088 |
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01-Apr-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Create entries in the P2M_MFN trees's to track 1-1 mappings .. when applicable. We need to track in the p2m_mfn and p2m_mfn_p the MFNs and pointers, respectivly, for the P2M entries that are allocated for the identity mappings. Without this, a PV domain with an E820 that triggers the 1-1 mapping to kick in, won't be able to be restored as the P2M won't have the identity mappings. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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8a91707d |
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20-Apr-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Add EXPORT_SYMBOL_GPL to the M2P override functions. If the backends, which use these two functions, are compiled as a module we need these two functions to be exported. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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cf8d9163 |
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28-Feb-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m/m2p/gnttab: Support GNTMAP_host_map in the M2P override. We only supported the M2P (and P2M) override only for the GNTMAP_contains_pte type mappings. Meaning that we grants operations would "contain the machine address of the PTE to update" If the flag is unset, then the grant operation is "contains a host virtual address". The latter case means that the Hypervisor takes care of updating our page table (specifically the PTE entry) with the guest's MFN. As such we should not try to do anything with the PTE. Previous to this patch we would try to clear the PTE which resulted in Xen hypervisor being upset with us: (XEN) mm.c:1066:d0 Attempt to implicitly unmap a granted PTE c0100000ccc59067 (XEN) domain_crash called from mm.c:1067 (XEN) Domain 0 (vcpu#0) crashed on cpu#3: (XEN) ----[ Xen-4.0-110228 x86_64 debug=y Not tainted ]---- and crashing us. This patch allows us to inhibit the PTE clearing in the PV guest if the GNTMAP_contains_pte is not set. On the m2p_remove_override path we provide the same parameter. Sadly in the grant-table driver we do not have a mechanism to tell m2p_remove_override whether to clear the PTE or not. Since the grant-table driver is used by user-space, we can safely assume that it operates only on PTE's. Hence the implementation for it to work on !GNTMAP_contains_pte returns -EOPNOTSUPP. In the future we can implement the support for this. It will require some extra accounting structure to keep track of the page[i], and the flag. [v1: Added documentation details, made it return -EOPNOTSUPP instead of trying to do a half-way implementation] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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b83c6e55 |
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24-Mar-2011 |
Randy Dunlap <randy.dunlap@oracle.com> |
xen: fix p2m section mismatches Fix section mismatch warnings: set_phys_range_identity() is called by __init xen_set_identity(), so also mark set_phys_range_identity() as __init. then: __early_alloc_p2m() is called set_phys_range_identity(), so also mark __early_alloc_p2m() as __init. WARNING: arch/x86/built-in.o(.text+0x7856): Section mismatch in reference from the function __early_alloc_p2m() to the function .init.text:extend_brk() The function __early_alloc_p2m() references the function __init extend_brk(). This is often because __early_alloc_p2m lacks a __init annotation or the annotation of extend_brk is wrong. WARNING: arch/x86/built-in.o(.text+0x7967): Section mismatch in reference from the function set_phys_range_identity() to the function .init.text:extend_brk() The function set_phys_range_identity() references the function __init extend_brk(). This is often because set_phys_range_identity lacks a __init annotation or the annotation of extend_brk is wrong. [v2: Per Stephen Hemming recommonedation made __early_alloc_p2m static] Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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b254244d |
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24-Mar-2011 |
Daniel De Graaf <dgdegra@tycho.nsa.gov> |
xen/p2m: Allocate p2m tracking pages on override It is possible to add a p2m override on pages that are currently mapped to INVALID_P2M_ENTRY; in particular, this will happen when using ballooned pages in gntdev. This means that set_phys_to_machine must be used instead of __set_phys_to_machine. Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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2222e71b |
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22-Dec-2010 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/debugfs: Add 'p2m' file for printing out the P2M layout. We walk over the whole P2M tree and construct a simplified view of which PFN regions belong to what level and what type they are. Only enabled if CONFIG_XEN_DEBUG_FS is set. [v2: UNKN->UNKNOWN, use uninitialized_var] [v3: Rebased on top of mmu->p2m code split] [v4: Fixed the else if] Reviewed-by: Ian Campbell <Ian.Campbell@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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c7617798 |
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18-Jan-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/mmu: WARN_ON when racing to swap middle leaf. The initial bootup code uses set_phys_to_machine quite a lot, and after bootup it would be used by the balloon driver. The balloon driver does have mutex lock so this should not be necessary - but just in case, add a WARN_ON if we do hit this scenario. If we do fail this, it is OK to continue as there is a backup mechanism (VM_IO) that can bypass the P2M and still set the _PAGE_IOMAP flags. [v2: Change from WARN to BUG_ON] [v3: Rebased on top of xen->p2m code split] [v4: Change from BUG_ON to WARN] Reviewed-by: Ian Campbell <Ian.Campbell@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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f4cec35b |
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18-Jan-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/mmu: Add the notion of identity (1-1) mapping. Our P2M tree structure is a three-level. On the leaf nodes we set the Machine Frame Number (MFN) of the PFN. What this means is that when one does: pfn_to_mfn(pfn), which is used when creating PTE entries, you get the real MFN of the hardware. When Xen sets up a guest it initially populates a array which has descending (or ascending) MFN values, as so: idx: 0, 1, 2 [0x290F, 0x290E, 0x290D, ..] so pfn_to_mfn(2)==0x290D. If you start, restart many guests that list starts looking quite random. We graft this structure on our P2M tree structure and stick in those MFN in the leafs. But for all other leaf entries, or for the top root, or middle one, for which there is a void entry, we assume it is "missing". So pfn_to_mfn(0xc0000)=INVALID_P2M_ENTRY. We add the possibility of setting 1-1 mappings on certain regions, so that: pfn_to_mfn(0xc0000)=0xc0000 The benefit of this is, that we can assume for non-RAM regions (think PCI BARs, or ACPI spaces), we can create mappings easily b/c we get the PFN value to match the MFN. For this to work efficiently we introduce one new page p2m_identity and allocate (via reserved_brk) any other pages we need to cover the sides (1GB or 4MB boundary violations). All entries in p2m_identity are set to INVALID_P2M_ENTRY type (Xen toolstack only recognizes that and MFNs, no other fancy value). On lookup we spot that the entry points to p2m_identity and return the identity value instead of dereferencing and returning INVALID_P2M_ENTRY. If the entry points to an allocated page, we just proceed as before and return the PFN. If the PFN has IDENTITY_FRAME_BIT set we unmask that in appropriate functions (pfn_to_mfn). The reason for having the IDENTITY_FRAME_BIT instead of just returning the PFN is that we could find ourselves where pfn_to_mfn(pfn)==pfn for a non-identity pfn. To protect ourselves against we elect to set (and get) the IDENTITY_FRAME_BIT on all identity mapped PFNs. This simplistic diagram is used to explain the more subtle piece of code. There is also a digram of the P2M at the end that can help. Imagine your E820 looking as so: 1GB 2GB /-------------------+---------\/----\ /----------\ /---+-----\ | System RAM | Sys RAM ||ACPI| | reserved | | Sys RAM | \-------------------+---------/\----/ \----------/ \---+-----/ ^- 1029MB ^- 2001MB [1029MB = 263424 (0x40500), 2001MB = 512256 (0x7D100), 2048MB = 524288 (0x80000)] And dom0_mem=max:3GB,1GB is passed in to the guest, meaning memory past 1GB is actually not present (would have to kick the balloon driver to put it in). When we are told to set the PFNs for identity mapping (see patch: "xen/setup: Set identity mapping for non-RAM E820 and E820 gaps.") we pass in the start of the PFN and the end PFN (263424 and 512256 respectively). The first step is to reserve_brk a top leaf page if the p2m[1] is missing. The top leaf page covers 512^2 of page estate (1GB) and in case the start or end PFN is not aligned on 512^2*PAGE_SIZE (1GB) we loop on aligned 1GB PFNs from start pfn to end pfn. We reserve_brk top leaf pages if they are missing (means they point to p2m_mid_missing). With the E820 example above, 263424 is not 1GB aligned so we allocate a reserve_brk page which will cover the PFNs estate from 0x40000 to 0x80000. Each entry in the allocate page is "missing" (points to p2m_missing). Next stage is to determine if we need to do a more granular boundary check on the 4MB (or 2MB depending on architecture) off the start and end pfn's. We check if the start pfn and end pfn violate that boundary check, and if so reserve_brk a middle (p2m[x][y]) leaf page. This way we have a much finer granularity of setting which PFNs are missing and which ones are identity. In our example 263424 and 512256 both fail the check so we reserve_brk two pages. Populate them with INVALID_P2M_ENTRY (so they both have "missing" values) and assign them to p2m[1][2] and p2m[1][488] respectively. At this point we would at minimum reserve_brk one page, but could be up to three. Each call to set_phys_range_identity has at maximum a three page cost. If we were to query the P2M at this stage, all those entries from start PFN through end PFN (so 1029MB -> 2001MB) would return INVALID_P2M_ENTRY ("missing"). The next step is to walk from the start pfn to the end pfn setting the IDENTITY_FRAME_BIT on each PFN. This is done in 'set_phys_range_identity'. If we find that the middle leaf is pointing to p2m_missing we can swap it over to p2m_identity - this way covering 4MB (or 2MB) PFN space. At this point we do not need to worry about boundary aligment (so no need to reserve_brk a middle page, figure out which PFNs are "missing" and which ones are identity), as that has been done earlier. If we find that the middle leaf is not occupied by p2m_identity or p2m_missing, we dereference that page (which covers 512 PFNs) and set the appropriate PFN with IDENTITY_FRAME_BIT. In our example 263424 and 512256 end up there, and we set from p2m[1][2][256->511] and p2m[1][488][0->256] with IDENTITY_FRAME_BIT set. All other regions that are void (or not filled) either point to p2m_missing (considered missing) or have the default value of INVALID_P2M_ENTRY (also considered missing). In our case, p2m[1][2][0->255] and p2m[1][488][257->511] contain the INVALID_P2M_ENTRY value and are considered "missing." This is what the p2m ends up looking (for the E820 above) with this fabulous drawing: p2m /--------------\ /-----\ | &mfn_list[0],| /-----------------\ | 0 |------>| &mfn_list[1],| /---------------\ | ~0, ~0, .. | |-----| | ..., ~0, ~0 | | ~0, ~0, [x]---+----->| IDENTITY [@256] | | 1 |---\ \--------------/ | [p2m_identity]+\ | IDENTITY [@257] | |-----| \ | [p2m_identity]+\\ | .... | | 2 |--\ \-------------------->| ... | \\ \----------------/ |-----| \ \---------------/ \\ | 3 |\ \ \\ p2m_identity |-----| \ \-------------------->/---------------\ /-----------------\ | .. +->+ | [p2m_identity]+-->| ~0, ~0, ~0, ... | \-----/ / | [p2m_identity]+-->| ..., ~0 | / /---------------\ | .... | \-----------------/ / | IDENTITY[@0] | /-+-[x], ~0, ~0.. | / | IDENTITY[@256]|<----/ \---------------/ / | ~0, ~0, .... | | \---------------/ | p2m_missing p2m_missing /------------------\ /------------\ | [p2m_mid_missing]+---->| ~0, ~0, ~0 | | [p2m_mid_missing]+---->| ..., ~0 | \------------------/ \------------/ where ~0 is INVALID_P2M_ENTRY. IDENTITY is (PFN | IDENTITY_BIT) Reviewed-by: Ian Campbell <ian.campbell@citrix.com> [v5: Changed code to use ranges, added ASCII art] [v6: Rebased on top of xen->p2m code split] [v4: Squished patches in just this one] [v7: Added RESERVE_BRK for potentially allocated pages] [v8: Fixed alignment problem] [v9: Changed 1<<3X to 1<<BITS_PER_LONG-X] [v10: Copied git commit description in the p2m code + Add Review tag] [v11: Title had '2-1' - should be '1-1' mapping] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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6eaa412f |
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18-Jan-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen: Mark all initial reserved pages for the balloon as INVALID_P2M_ENTRY. With this patch, we diligently set regions that will be used by the balloon driver to be INVALID_P2M_ENTRY and under the ownership of the balloon driver. We are OK using the __set_phys_to_machine as we do not expect to be allocating any P2M middle or entries pages. The set_phys_to_machine has the side-effect of potentially allocating new pages and we do not want that at this stage. We can do this because xen_build_mfn_list_list will have already allocated all such pages up to xen_max_p2m_pfn. We also move the check for auto translated physmap down the stack so it is present in __set_phys_to_machine. [v2: Rebased with mmu->p2m code split] Reviewed-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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44b46c3e |
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11-Feb-2011 |
Ian Campbell <Ian.Campbell@eu.citrix.com> |
xen: annotate functions which only call into __init at start of day Both xen_hvm_init_shared_info and xen_build_mfn_list_list can be called at resume time as well as at start of day but only reference __init functions (extend_brk) at start of day. Hence annotate with __ref. WARNING: arch/x86/built-in.o(.text+0x4f1): Section mismatch in reference from the function xen_hvm_init_shared_info() to the function .init.text:extend_brk() The function xen_hvm_init_shared_info() references the function __init extend_brk(). This is often because xen_hvm_init_shared_info lacks a __init annotation or the annotation of extend_brk is wrong. xen_hvm_init_shared_info calls extend_brk() iff !shared_info_page and initialises shared_info_page with the result. This happens at start of day only. WARNING: arch/x86/built-in.o(.text+0x599b): Section mismatch in reference from the function xen_build_mfn_list_list() to the function .init.text:extend_brk() The function xen_build_mfn_list_list() references the function __init extend_brk(). This is often because xen_build_mfn_list_list lacks a __init annotation or the annotation of extend_brk is wrong. (this warning occurs multiple times) xen_build_mfn_list_list only calls extend_brk() at boot time, while building the initial mfn list list Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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6b08cfeb |
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11-Feb-2011 |
Ian Campbell <ian.campbell@citrix.com> |
xen p2m: annotate variable which appears unused CC arch/x86/xen/p2m.o arch/x86/xen/p2m.c: In function 'm2p_remove_override': arch/x86/xen/p2m.c:460: warning: 'address' may be used uninitialized in this function arch/x86/xen/p2m.c: In function 'm2p_add_override': arch/x86/xen/p2m.c:426: warning: 'address' may be used uninitialized in this function In actual fact address is inialised in one "if (!PageHighMem(page))" statement and used in a second and so is always initialised before use. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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cf04d120 |
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27-Jan-2011 |
Stefan Bader <stefan.bader@canonical.com> |
xen/p2m: Mark INVALID_P2M_ENTRY the mfn_list past max_pfn. In case the mfn_list does not have enough entries to fill a p2m page we do not want the entries from max_pfn up to the boundary to be filled with unknown values. Hence set them to INVALID_P2M_ENTRY. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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8e1b4cf2 |
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20-Jan-2011 |
Stefan Bader <stefan.bader@canonical.com> |
xen: p2m: correctly initialize partial p2m leaf After changing the p2m mapping to a tree by commit 58e05027b530ff081ecea68e38de8d59db8f87e0 xen: convert p2m to a 3 level tree and trying to boot a DomU with 615MB of memory, the following crash was observed in the dump: kernel direct mapping tables up to 26f00000 @ 1ec4000-1fff000 BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<c0107397>] xen_set_pte+0x27/0x60 *pdpt = 0000000000000000 *pde = 0000000000000000 Adding further debug statements showed that when trying to set up pfn=0x26700 the returned mapping was invalid. pfn=0x266ff calling set_pte(0xc1fe77f8, 0x6b3003) pfn=0x26700 calling set_pte(0xc1fe7800, 0x3) Although the last_pfn obtained from the startup info is 0x26700, which should in turn not be hit, the additional 8MB which are added as extra memory normally seem to be ok. This lead to looking into the initial p2m tree construction, which uses the smaller value and assuming that there is other code handling the extra memory. When the p2m tree is set up, the leaves are directly pointed to the array which the domain builder set up. But if the mapping is not on a boundary that fits into one p2m page, this will result in the last leaf being only partially valid. And as the invalid entries are not initialized in that case, things go badly wrong. I am trying to fix that by checking whether the current leaf is a complete map and if not, allocate a completely new page and copy only the valid pointers there. This may not be the most efficient or elegant solution, but at least it seems to allow me booting DomUs with memory assignments all over the range. BugLink: http://bugs.launchpad.net/bugs/686692 [v2: Redid a bit of commit wording and fixed a compile warning] Signed-off-by: Stefan Bader <stefan.bader@canonical.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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e1b478e4 |
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11-Jan-2011 |
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
xen/p2m: Fix module linking error. Fixes: ERROR: "m2p_find_override_pfn" [drivers/block/xen-blkfront.ko] undefined! Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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87f1d40a |
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13-Dec-2010 |
Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> |
xen p2m: clear the old pte when adding a page to m2p_override 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>
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9b705f0e |
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10-Dec-2010 |
Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
xen p2m: transparently change the p2m mappings in the m2p override In m2p_add_override store the original mfn into page->index and then change the p2m mapping, setting mfns as FOREIGN_FRAME. In m2p_remove_override restore the original mapping. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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448f2831 |
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15-Dec-2010 |
Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> |
xen: add m2p override mechanism Add a simple hashtable based mechanism to override some portions of the m2p, so that we can find out the pfn corresponding to an mfn of a granted page. In fact entries corresponding to granted pages in the m2p hold the original pfn value of the page in the source domain that granted it. 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>
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b5eafe92 |
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06-Dec-2010 |
Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> |
xen: move p2m handling to separate file Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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