Commit Graph

6 Commits

Author SHA1 Message Date
Stefano Stabellini
d50582e06f xen/arm: remove mach_to_phys rbtree
Remove the rbtree used to keep track of machine to physical mappings:
the frontend can grant the same page multiple times, leading to errors
inserting or removing entries from the mach_to_phys tree.

Linux only needed to know the physical address corresponding to a given
machine address in swiotlb-xen. Now that swiotlb-xen can call the
xen_dma_* functions passing the machine address directly, we can remove
it.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Tested-by: Denis Schneider <v1ne2go@gmail.com>
2014-09-11 18:11:53 +00:00
Zoltan Kiss
1429d46df4 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>
2014-03-18 14:40:19 +00:00
Stefano Stabellini
f9c7ec1649 xen/arm: p2m_init and p2m_lock should be static
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-11-18 15:33:10 +00:00
Josh Boyer
c8999a889f arm/xen: Export phys_to_mach to fix Xen module link errors
Various xen drivers fail to link when built as modules with the following
error:

ERROR: "phys_to_mach" [drivers/xen/xen-gntalloc.ko] undefined!
ERROR: "phys_to_mach" [drivers/net/xen-netfront.ko] undefined!
ERROR: "phys_to_mach" [drivers/net/xen-netback/xen-netback.ko] undefined!
ERROR: "phys_to_mach" [drivers/block/xen-blkfront.ko] undefined!

The mfn_to_pfn and pfn_to_mfn functions get inlined in these modules and
those functions require phys_to_mach.  Export the symbol to fix the link
errors.

Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2013-11-18 15:32:45 +00:00
Konrad Rzeszutek Wilk
e1d8f62ad4 Merge remote-tracking branch 'stefano/swiotlb-xen-9.1' into stable/for-linus-3.13
* stefano/swiotlb-xen-9.1:
  swiotlb-xen: fix error code returned by xen_swiotlb_map_sg_attrs
  swiotlb-xen: static inline xen_phys_to_bus, xen_bus_to_phys, xen_virt_to_bus and range_straddles_page_boundary
  grant-table: call set_phys_to_machine after mapping grant refs
  arm,arm64: do not always merge biovec if we are running on Xen
  swiotlb: print a warning when the swiotlb is full
  swiotlb-xen: use xen_dma_map/unmap_page, xen_dma_sync_single_for_cpu/device
  xen: introduce xen_dma_map/unmap_page and xen_dma_sync_single_for_cpu/device
  swiotlb-xen: use xen_alloc/free_coherent_pages
  xen: introduce xen_alloc/free_coherent_pages
  arm64/xen: get_dma_ops: return xen_dma_ops if we are running as xen_initial_domain
  arm/xen: get_dma_ops: return xen_dma_ops if we are running as xen_initial_domain
  swiotlb-xen: introduce xen_swiotlb_set_dma_mask
  xen/arm,arm64: enable SWIOTLB_XEN
  xen: make xen_create_contiguous_region return the dma address
  xen/x86: allow __set_phys_to_machine for autotranslate guests
  arm/xen,arm64/xen: introduce p2m
  arm64: define DMA_ERROR_CODE
  arm: make SWIOTLB available

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Conflicts:
	arch/arm/include/asm/dma-mapping.h
	drivers/xen/swiotlb-xen.c

[Conflicts arose b/c "arm: make SWIOTLB available" v8 was in Stefano's
branch, while I had v9 + Ack from Russel. I also fixed up white-space
issues]
2013-11-08 16:10:48 -05:00
Stefano Stabellini
4a19138c65 arm/xen,arm64/xen: introduce p2m
Introduce physical to machine and machine to physical tracking
mechanisms based on rbtrees for arm/xen and arm64/xen.

We need it because any guests on ARM are an autotranslate guests,
therefore a physical address is potentially different from a machine
address. When programming a device to do DMA, we need to be
extra-careful to use machine addresses rather than physical addresses to
program the device. Therefore we need to know the physical to machine
mappings.

For the moment we assume that dom0 starts with a 1:1 physical to machine
mapping, in other words physical addresses correspond to machine
addresses. However when mapping a foreign grant reference, obviously the
1:1 model doesn't work anymore. So at the very least we need to be able
to track grant mappings.

We need locking to protect accesses to the two trees.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

Changes in v8:
- move pfn_to_mfn and mfn_to_pfn to page.h as static inline functions;
- no need to walk the tree if phys_to_mach.rb_node is NULL;
- correctly handle multipage p2m entries;
- substitute the spin_lock with a rwlock.
2013-10-17 16:22:27 +00:00