Add an argument to swiotlb_tbl_map_single that specifies the desired
alignment of the allocated buffer. This is used by dma-iommu to ensure
the buffer is aligned to the iova granule size when using swiotlb with
untrusted sub-granule mappings. This addresses an issue where adjacent
slots could be exposed to the untrusted device if IO_TLB_SIZE < iova
granule < PAGE_SIZE.
Signed-off-by: David Stevens <stevensd@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210929023300.335969-7-stevensd@google.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Since commit 69031f5008 ("swiotlb: Set dev->dma_io_tlb_mem to the
swiotlb pool used"), 'struct device' may hold a copy of the global
'io_default_tlb_mem' pointer if the device is using swiotlb for DMA. A
subsequent call to swiotlb_exit() will therefore leave dangling pointers
behind in these device structures, resulting in KASAN splats such as:
| BUG: KASAN: use-after-free in __iommu_dma_unmap_swiotlb+0x64/0xb0
| Read of size 8 at addr ffff8881d7830000 by task swapper/0/0
|
| CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc3-debug #1
| Hardware name: HP HP Desktop M01-F1xxx/87D6, BIOS F.12 12/17/2020
| Call Trace:
| <IRQ>
| dump_stack+0x9c/0xcf
| print_address_description.constprop.0+0x18/0x130
| kasan_report.cold+0x7f/0x111
| __iommu_dma_unmap_swiotlb+0x64/0xb0
| nvme_pci_complete_rq+0x73/0x130
| blk_complete_reqs+0x6f/0x80
| __do_softirq+0xfc/0x3be
Convert 'io_default_tlb_mem' to a static structure, so that the
per-device pointers remain valid after swiotlb_exit() has been invoked.
All users are updated to reference the static structure directly, using
the 'nslabs' field to determine whether swiotlb has been initialised.
The 'slots' array is still allocated dynamically and referenced via a
pointer rather than a flexible array member.
Cc: Claire Chang <tientzu@chromium.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Fixes: 69031f5008 ("swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
Add the initialization function to create restricted DMA pools from
matching reserved-memory nodes.
Regardless of swiotlb setting, the restricted DMA pool is preferred if
available.
The restricted DMA pools provide a basic level of protection against the
DMA overwriting buffer contents at unexpected times. However, to protect
against general data leakage and system memory corruption, the system
needs to provide a way to lock down the memory access, e.g., MPU.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Add the functions, swiotlb_{alloc,free} and is_swiotlb_for_alloc to
support the memory allocation from restricted DMA pool.
The restricted DMA pool is preferred if available.
Note that since coherent allocation needs remapping, one must set up
another device coherent pool by shared-dma-pool and use
dma_alloc_from_dev_coherent instead for atomic coherent allocation.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Propagate the swiotlb_force into io_tlb_default_mem->force_bounce and
use it to determine whether to bounce the data or not. This will be
useful later to allow for different pools.
Signed-off-by: Claire Chang <tientzu@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
Tested-by: Will Deacon <will@kernel.org>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: Includes Will's fix]
All callers just use it to check if swiotlb is active at all, for which
they can just use is_swiotlb_active. In the longer run drivers need
to stop using is_swiotlb_active as well, but let's do the simple step
first.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Instead of allocating ->list and ->orig_addr separately just do one
dynamic allocation for the actual io_tlb_mem structure. This simplifies
a lot of the initialization code, and also allows to just check
io_tlb_default_mem to see if swiotlb is in use.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Added a new struct, io_tlb_mem, as the IO TLB memory pool descriptor and
moved relevant global variables into that struct.
This will be useful later to allow for restricted DMA pool.
Signed-off-by: Claire Chang <tientzu@chromium.org>
[hch: rebased]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Split swiotlb_tbl_sync_single into two separate funtions for the to device
and to cpu synchronization.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Now that swiotlb remembers the allocation size there is no need to pass
it back to swiotlb_tbl_unmap_single.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Add a new IO_TLB_SIZE define instead open coding it using
IO_TLB_SHIFT all over.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jianxiong Gao <jxgao@google.com>
Tested-by: Jianxiong Gao <jxgao@google.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
For SEV, all DMA to and from guest has to use shared (un-encrypted) pages.
SEV uses SWIOTLB to make this happen without requiring changes to device
drivers. However, depending on the workload being run, the default 64MB
of it might not be enough and it may run out of buffers to use for DMA,
resulting in I/O errors and/or performance degradation for high
I/O workloads.
Adjust the default size of SWIOTLB for SEV guests using a
percentage of the total memory available to guest for the SWIOTLB buffers.
Adds a new sev_setup_arch() function which is invoked from setup_arch()
and it calls into a new swiotlb generic code function swiotlb_adjust_size()
to do the SWIOTLB buffer adjustment.
v5 fixed build errors and warnings as
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Co-developed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Pull vhost fixes from Michael Tsirkin:
"Fixes all over the place, most notably vhost scsi IO error fixes"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost scsi: Add support for LUN resets.
vhost scsi: add lun parser helper
vhost scsi: fix cmd completion race
vhost scsi: alloc cmds per vq instead of session
vhost: add helper to check if a vq has been setup
vdpasim: fix "mac_pton" undefined error
swiotlb: using SIZE_MAX needs limits.h included
The tbl_dma_addr argument is used to check the DMA boundary for the
allocations, and thus needs to be a dma_addr_t. swiotlb-xen instead
passed a physical address, which could lead to incorrect results for
strange offsets. Fix this by removing the parameter entirely and hard
code the DMA address for io_tlb_start instead.
Fixes: 91ffe4ad53 ("swiotlb-xen: introduce phys_to_dma/dma_to_phys translations")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
After merging the drm-misc tree, linux-next build (arm
multi_v7_defconfig) failed like this:
In file included from drivers/gpu/drm/nouveau/nouveau_ttm.c:26:
include/linux/swiotlb.h: In function 'swiotlb_max_mapping_size':
include/linux/swiotlb.h:99:9: error: 'SIZE_MAX' undeclared (first use in this function)
99 | return SIZE_MAX;
| ^~~~~~~~
include/linux/swiotlb.h:7:1: note: 'SIZE_MAX' is defined in header '<stdint.h>'; did you forget to '#include <stdint.h>'?
6 | #include <linux/init.h>
+++ |+#include <stdint.h>
7 | #include <linux/types.h>
include/linux/swiotlb.h:99:9: note: each undeclared identifier is reported only once for each function it appears in
99 | return SIZE_MAX;
| ^~~~~~~~
Caused by commit
abe420bfae ("swiotlb: Introduce swiotlb_max_mapping_size()")
but only exposed by commit "drm/nouveu: fix swiotlb include"
Fix it by including linux/limits.h as appropriate.
Fixes: abe420bfae ("swiotlb: Introduce swiotlb_max_mapping_size()")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20201102124327.2f82b2a7@canb.auug.org.au
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Compiler is not happy about one function prototype:
CC kernel/dma/swiotlb.o
kernel/dma/swiotlb.c:275:1: warning: no previous prototype for ‘swiotlb_late_init_with_default_size’ [-Wmissing-prototypes]
275 | swiotlb_late_init_with_default_size(size_t default_size)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Since it's used outside of the module, move its declaration to the header
from the user.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Untangle the way how dma_direct_map_page calls into swiotlb to be able
to properly report errors where the swiotlb DMA address overflows the
mask separately from overflows in the !swiotlb case. This means that
siotlb_map now has to do a little more work that duplicates
dma_direct_map_page, but doing so greatly simplifies the calling
convention.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This splits the size parameter to swiotlb_tbl_map_single() and
swiotlb_tbl_unmap_single() into an alloc_size and a mapping_size
parameter, where the latter one is rounded up to the iommu page
size.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Pull virtio updates from Michael Tsirkin:
"Several fixes, most notably fix for virtio on swiotlb systems"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
vhost: silence an unused-variable warning
virtio: hint if callbacks surprisingly might sleep
virtio-ccw: wire up ->bus_name callback
s390/virtio: handle find on invalid queue gracefully
virtio-ccw: diag 500 may return a negative cookie
virtio_balloon: remove the unnecessary 0-initialization
virtio-balloon: improve update_balloon_size_func
virtio-blk: Consider virtio_max_dma_size() for maximum segment size
virtio: Introduce virtio_max_dma_size()
dma: Introduce dma_max_mapping_size()
swiotlb: Add is_swiotlb_active() function
swiotlb: Introduce swiotlb_max_mapping_size()
The function returns the maximum size that can be remapped
by the SWIOTLB implementation. This function will be later
exposed to users through the DMA-API.
Cc: stable@vger.kernel.org
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The only user left is powerpc, but even there the generic dma-direct
version works just as well, given that we guarantee that the swiotlb
buffer must always be addressable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
While the dma-direct code is (relatively) clean and simple we actually
have to use the swiotlb ops for the mapping on many architectures due
to devices with addressing limits. Instead of keeping two
implementations around this commit allows the dma-direct
implementation to call the swiotlb bounce buffering functions and
thus share the guts of the mapping implementation. This also
simplified the dma-mapping setup on a few architectures where we
don't have to differenciate which implementation to use.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Tony Luck <tony.luck@intel.com>