Dan Williams 94db151dc8 vfio: disable filesystem-dax page pinning ... Filesystem-DAX is incompatible with 'longterm' page pinning. Without page cache indirection a DAX mapping maps filesystem blocks directly. This means that the filesystem must not modify a file's block map while any page in a mapping is pinned. In order to prevent the situation of userspace holding of filesystem operations indefinitely, disallow 'longterm' Filesystem-DAX mappings. RDMA has the same conflict and the plan there is to add a 'with lease' mechanism to allow the kernel to notify userspace that the mapping is being torn down for block-map maintenance. Perhaps something similar can be put in place for vfio. Note that xfs and ext4 still report: "DAX enabled. Warning: EXPERIMENTAL, use at your own risk" ...at mount time, and resolving the dax-dma-vs-truncate problem is one of the last hurdles to remove that designation. Acked-by: Alex Williamson <alex.williamson@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: kvm@vger.kernel.org Cc: <stable@vger.kernel.org> Reported-by: Haozhong Zhang <haozhong.zhang@intel.com> Tested-by: Haozhong Zhang <haozhong.zhang@intel.com> Fixes: d475c6346a ("dax,ext2: replace XIP read and write with DAX I/O") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>		2018-03-02 18:00:04 -08:00
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mdev
pci
platform
Kconfig
Makefile
vfio_iommu_spapr_tce.c
vfio_iommu_type1.c
vfio_spapr_eeh.c
vfio.c
virqfd.c