kernel/git/stable/linux-stable.git/drivers/xen/privcmd.c, branch linux-4.3.y

Merge branch 'akpm' (patches from Andrew)

2015-09-11T01:19:42+00:00

Merge third patch-bomb from Andrew Morton: - even more of the rest of MM - lib/ updates - checkpatch updates - small changes to a few scruffy filesystems - kmod fixes/cleanups - kexec updates - a dma-mapping cleanup series from hch * emailed patches from Andrew Morton : (81 commits) dma-mapping: consolidate dma_set_mask dma-mapping: consolidate dma_supported dma-mapping: cosolidate dma_mapping_error dma-mapping: consolidate dma_{alloc,free}_noncoherent dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent} mm: use vma_is_anonymous() in create_huge_pmd() and wp_huge_pmd() mm: make sure all file VMAs have ->vm_ops set mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff() mm: mark most vm_operations_struct const namei: fix warning while make xmldocs caused by namei.c ipc: convert invalid scenarios to use WARN_ON zlib_deflate/deftree: remove bi_reverse() lib/decompress_unlzma: Do a NULL check for pointer lib/decompressors: use real out buf size for gunzip with kernel fs/affs: make root lookup from blkdev logical size sysctl: fix int -> unsigned long assignments in INT_MIN case kexec: export KERNEL_IMAGE_SIZE to vmcoreinfo kexec: align crash_notes allocation to make it be inside one physical page kexec: remove unnecessary test in kimage_alloc_crash_control_pages() kexec: split kexec_load syscall from kexec core code ...

mm: mark most vm_operations_struct const

2015-09-10T20:29:01+00:00

With two exceptions (drm/qxl and drm/radeon) all vm_operations_struct structs should be constant. Signed-off-by: Kirill A. Shutemov Reviewed-by: Oleg Nesterov Cc: "H. Peter Anvin" Cc: Andy Lutomirski Cc: Dave Hansen Cc: Ingo Molnar Cc: Minchan Kim Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

xen/privcmd: Further s/MFN/GFN/ clean-up

2015-09-08T17:03:54+00:00

The privcmd code is mixing the usage of GFN and MFN within the same functions which make the code difficult to understand when you only work with auto-translated guests. The privcmd driver is only dealing with GFN so replace all the mention of MFN into GFN. The ioctl structure used to map foreign change has been left unchanged given that the userspace is using it. Nonetheless, add a comment to explain the expected value within the "mfn" field. Signed-off-by: Julien Grall Reviewed-by: David Vrabel Signed-off-by: David Vrabel

xen/privcmd: improve performance of MMAPBATCH_V2

2015-03-16T14:49:15+00:00

Make the IOCTL_PRIVCMD_MMAPBATCH_V2 (and older V1 version) map multiple frames at a time rather than one at a time, despite the pages being non-consecutive GFNs. xen_remap_foreign_mfn_array() is added which maps an array of GFNs (instead of a consecutive range of GFNs). Since per-frame errors are returned in an array, privcmd must set the MMAPBATCH_V1 error bits as part of the "report errors" phase, after all the frames are mapped. Migrate times are significantly improved (when using a PV toolstack domain). For example, for an idle 12 GiB PV guest: Before After real 0m38.179s 0m26.868s user 0m15.096s 0m13.652s sys 0m28.988s 0m18.732s Signed-off-by: David Vrabel Reviewed-by: Stefano Stabellini

x86/xen: allow privcmd hypercalls to be preempted

2015-02-23T16:30:24+00:00

Hypercalls submitted by user space tools via the privcmd driver can take a long time (potentially many 10s of seconds) if the hypercall has many sub-operations. A fully preemptible kernel may deschedule such as task in any upcall called from a hypercall continuation. However, in a kernel with voluntary or no preemption, hypercall continuations in Xen allow event handlers to be run but the task issuing the hypercall will not be descheduled until the hypercall is complete and the ioctl returns to user space. These long running tasks may also trigger the kernel's soft lockup detection. Add xen_preemptible_hcall_begin() and xen_preemptible_hcall_end() to bracket hypercalls that may be preempted. Use these in the privcmd driver. When returning from an upcall, call xen_maybe_preempt_hcall() which adds a schedule point if if the current task was within a preemptible hypercall. Since _cond_resched() can move the task to a different CPU, clear and set xen_in_preemptible_hcall around the call. Signed-off-by: David Vrabel Reviewed-by: Boris Ostrovsky

xen: privcmd: do not return pages which we have failed to unmap

2013-12-06T17:55:56+00:00

This failure represents a hypervisor issue, but if it does occur then nothing good can come of returning pages which still refer to a foreign owned page into the general allocation pool. Instead we are forced to leak them. Log that we have done so. The potential for failure only exists for autotranslated guest (e.g. ARM and x86 PVH). Signed-off-by: Ian Campbell Signed-off-by: Stefano Stabellini Reviewed-by: David Vrabel

Xen: Fix retry calls into PRIVCMD_MMAPBATCH*.

2013-08-30T12:44:53+00:00

When a foreign mapper attempts to map guest frames that are paged out, the mapper receives an ENOENT response and will have to try again while a helper process pages the target frame back in. Gating checks on PRIVCMD_MMAPBATCH* ioctl args were preventing retries of mapping calls. Permit subsequent calls to update a sub-range of the VMA, iff nothing is yet mapped in that range. Since it is now valid to call PRIVCMD_MMAPBATCH* multiple times, only set vma->vm_private_data if the parameters are valid and (if necessary) the pages for the auto_translated_physmap case have been allocated. This prevents subsequent calls from incorrectly entering the 'retry' path when there are no pages allocated etc. Signed-off-by: Andres Lagar-Cavilla Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk

xen: Convert printks to pr_

2013-06-28T15:19:58+00:00

Convert printks to pr_ (excludes printk(KERN_DEBUG...) to be more consistent throughout the xen subsystem. Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME Coalesce formats and add missing word spaces Add missing newlines Align arguments and reflow to 80 columns Remove DRV_NAME from formats as pr_fmt adds the same content This does change some of the prefixes of these messages but it also does make them more consistent. Signed-off-by: Joe Perches Signed-off-by: Konrad Rzeszutek Wilk

xen/privcmd: fix condition in privcmd_close()

2013-05-15T14:23:40+00:00

The parenthesis are in the wrong place so the original code is equivalent to: if (!xen_feature(XENFEAT_writable_descriptor_tables)) { ... Which obviously was not intended. Signed-off-by: Dan Carpenter Signed-off-by: Konrad Rzeszutek Wilk

xen/privcmd: Fix mmap batch ioctl.

2013-01-15T21:00:52+00:00

1. If any individual mapping error happens, the V1 case will mark *all* operations as failed. Fixed. 2. The err_array was allocated with kcalloc, resulting in potentially O(n) page allocations. Refactor code to not use this array. Signed-off-by: Andres Lagar-Cavilla Signed-off-by: Konrad Rzeszutek Wilk