Fix multiple occurrences of duplicated words in kernel/.
Fix one typo/spello on the same line as a duplicate word. Change one
instance of "the the" to "that the". Otherwise just drop one of the
repeated words.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/98202fa6-8919-ef63-9efe-c0fad5ca7af1@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use and entirely separate code path for the DMA_ATTR_NO_KERNEL_MAPPING
path. This avoids any confusion about the ret type, and avoids lots of
attr checks and helpers that can be significantly simplified now.
It also ensures that common handling is applied to architetures still
using the arch alloc/free hooks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
This ensures dma_direct_alloc_pages will use the right gfp mask, as
well as keeping the code for that common between the two allocators.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Most of the dma_direct symbols should only be used by direct.c and
mapping.c, so move them to kernel/dma. In fact more of dma-direct.h
should eventually move, but that will require more coordination with
other subsystems.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Split out all the bits that are purely for dma_map_ops implementations
and related code into a new <linux/dma-map-ops.h> header so that they
don't get pulled into all the drivers. That also means the architecture
specific <asm/dma-mapping.h> is not pulled in by <linux/dma-mapping.h>
any more, which leads to a missing includes that were pulled in by the
x86 or arm versions in a few not overly portable drivers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
This API is the equivalent of alloc_pages, except that the returned memory
is guaranteed to be DMA addressable by the passed in device. The
implementation will also be used to provide a more sensible replacement
for DMA_ATTR_NON_CONSISTENT flag.
Additionally dma_alloc_noncoherent is switched over to use dma_alloc_pages
as its backend.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> (MIPS part)
The new field 'dma_range_map' in struct device is used to facilitate the
use of single or multiple offsets between mapping regions of cpu addrs and
dma addrs. It subsumes the role of "dev->dma_pfn_offset" which was only
capable of holding a single uniform offset and had no region bounds
checking.
The function of_dma_get_range() has been modified so that it takes a single
argument -- the device node -- and returns a map, NULL, or an error code.
The map is an array that holds the information regarding the DMA regions.
Each range entry contains the address offset, the cpu_start address, the
dma_start address, and the size of the region.
of_dma_configure() is the typical manner to set range offsets but there are
a number of ad hoc assignments to "dev->dma_pfn_offset" in the kernel
driver code. These cases now invoke the function
dma_direct_set_offset(dev, cpu_addr, dma_addr, size).
Signed-off-by: Jim Quinlan <james.quinlan@broadcom.com>
[hch: various interface cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
The __phys_to_dma vs phys_to_dma distinction isn't exactly obvious. Try
to improve the situation by renaming __phys_to_dma to
phys_to_dma_unencryped, and not forcing architectures that want to
override phys_to_dma to actually provide __phys_to_dma.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
There is no harm in just always clearing the SME encryption bit, while
significantly simplifying the interface.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Move the detailed gfp_t setup from __dma_direct_alloc_pages into the
caller to clean things up a little.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Just merge these helpers into the main dma_direct_{alloc,free} routines,
as the additional checks are always false for the two callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Add back a hook to optimize dcache flushing after reading executable
code using DMA. This gets ia64 out of the business of pretending to
be dma incoherent just for this optimization.
Signed-off-by: Christoph Hellwig <hch@lst.de>
When allocating coherent pool memory for an IOMMU mapping we don't care
about the DMA mask. Move the guess for the initial GFP mask into the
dma_direct_alloc_pages and pass dma_coherent_ok as a function pointer
argument so that it doesn't get applied to the IOMMU case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Amit Pundir <amit.pundir@linaro.org>
Inline the single page map/unmap/sync dma-direct calls into the now
out of line generic wrappers. This restores the behavior of a single
function call that we had before moving the generic calls out of line.
Besides the dma-mapping callers there are just a few callers in IOMMU
drivers that have a bypass mode, and more of those are going to be
switched to the generic bypass soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
For a long time the DMA API has been implemented inline in dma-mapping.h,
but the function bodies can be quite large. Move them all out of line.
This also removes all the dma_direct_* exports as those are just
implementation details and should never be used by drivers directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
dma_coherent_ok() checks if a physical memory area fits a device's DMA
constraints.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull networking fixes from David Miller:
1) Restore previous behavior of CAP_SYS_ADMIN wrt loading networking
BPF programs, from Maciej Żenczykowski.
2) Fix dropped broadcasts in mac80211 code, from Seevalamuthu
Mariappan.
3) Slay memory leak in nl80211 bss color attribute parsing code, from
Luca Coelho.
4) Get route from skb properly in ip_route_use_hint(), from Miaohe Lin.
5) Don't allow anything other than ARPHRD_ETHER in llc code, from Eric
Dumazet.
6) xsk code dips too deeply into DMA mapping implementation internals.
Add dma_need_sync and use it. From Christoph Hellwig
7) Enforce power-of-2 for BPF ringbuf sizes. From Andrii Nakryiko.
8) Check for disallowed attributes when loading flow dissector BPF
programs. From Lorenz Bauer.
9) Correct packet injection to L3 tunnel devices via AF_PACKET, from
Jason A. Donenfeld.
10) Don't advertise checksum offload on ipa devices that don't support
it. From Alex Elder.
11) Resolve several issues in TCP MD5 signature support. Missing memory
barriers, bogus options emitted when using syncookies, and failure
to allow md5 key changes in established states. All from Eric
Dumazet.
12) Fix interface leak in hsr code, from Taehee Yoo.
13) VF reset fixes in hns3 driver, from Huazhong Tan.
14) Make loopback work again with ipv6 anycast, from David Ahern.
15) Fix TX starvation under high load in fec driver, from Tobias
Waldekranz.
16) MLD2 payload lengths not checked properly in bridge multicast code,
from Linus Lüssing.
17) Packet scheduler code that wants to find the inner protocol
currently only works for one level of VLAN encapsulation. Allow
Q-in-Q situations to work properly here, from Toke
Høiland-Jørgensen.
18) Fix route leak in l2tp, from Xin Long.
19) Resolve conflict between the sk->sk_user_data usage of bpf reuseport
support and various protocols. From Martin KaFai Lau.
20) Fix socket cgroup v2 reference counting in some situations, from
Cong Wang.
21) Cure memory leak in mlx5 connection tracking offload support, from
Eli Britstein.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits)
mlxsw: pci: Fix use-after-free in case of failed devlink reload
mlxsw: spectrum_router: Remove inappropriate usage of WARN_ON()
net: macb: fix call to pm_runtime in the suspend/resume functions
net: macb: fix macb_suspend() by removing call to netif_carrier_off()
net: macb: fix macb_get/set_wol() when moving to phylink
net: macb: mark device wake capable when "magic-packet" property present
net: macb: fix wakeup test in runtime suspend/resume routines
bnxt_en: fix NULL dereference in case SR-IOV configuration fails
libbpf: Fix libbpf hashmap on (I)LP32 architectures
net/mlx5e: CT: Fix memory leak in cleanup
net/mlx5e: Fix port buffers cell size value
net/mlx5e: Fix 50G per lane indication
net/mlx5e: Fix CPU mapping after function reload to avoid aRFS RX crash
net/mlx5e: Fix VXLAN configuration restore after function reload
net/mlx5e: Fix usage of rcu-protected pointer
net/mxl5e: Verify that rpriv is not NULL
net/mlx5: E-Switch, Fix vlan or qos setting in legacy mode
net/mlx5: Fix eeprom support for SFP module
cgroup: Fix sock_cgroup_data on big-endian.
selftests: bpf: Fix detach from sockmap tests
...
Add a new API to check if calls to dma_sync_single_for_{device,cpu} are
required for a given DMA streaming mapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200629130359.2690853-2-hch@lst.de
When a coherent mapping is created in dma_direct_alloc_pages(), it needs
to be decrypted if the device requires unencrypted DMA before returning.
Fixes: 3acac06550 ("dma-mapping: merge the generic remapping helpers into dma-direct")
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
__change_page_attr() can fail which will cause set_memory_encrypted() and
set_memory_decrypted() to return non-zero.
If the device requires unencrypted DMA memory and decryption fails, simply
free the memory and fail.
If attempting to re-encrypt in the failure path and that encryption fails,
there is no alternative other than to leak the memory.
Fixes: c10f07aa27 ("dma/direct: Handle force decryption for DMA coherent buffers in common code")
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
If arch_dma_set_uncached() fails after memory has been decrypted, it needs
to be re-encrypted before freeing.
Fixes: fa7e2247c5 ("dma-direct: make uncached_kernel_address more general")
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
dma_alloc_contiguous() does size >> PAGE_SHIFT and set_memory_decrypted()
works at page granularity. It's necessary to page align the allocation
size in dma_direct_alloc_pages() for consistent behavior.
This also fixes an issue when arch_dma_prep_coherent() is called on an
unaligned allocation size for dma_alloc_need_uncached() when
CONFIG_DMA_DIRECT_REMAP is disabled but CONFIG_ARCH_HAS_DMA_SET_UNCACHED
is enabled.
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
nommu configfs can trivially map the coherent allocations to user space,
as no actual page table setup is required and the kernel and the user
space programs share the same address space.
Fixes: 62fcee9a3b ("dma-mapping: remove CONFIG_ARCH_NO_COHERENT_DMA_MMAP")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: dillon min <dillon.minfei@gmail.com>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
Tested-by: dillon min <dillon.minfei@gmail.com>
When a device requires unencrypted memory and the context does not allow
blocking, memory must be returned from the atomic coherent pools.
This avoids the remap when CONFIG_DMA_DIRECT_REMAP is not enabled and the
config only requires CONFIG_DMA_COHERENT_POOL. This will be used for
CONFIG_AMD_MEM_ENCRYPT in a subsequent patch.
Keep all memory in these pools unencrypted. When set_memory_decrypted()
fails, this prohibits the memory from being added. If adding memory to
the genpool fails, and set_memory_encrypted() subsequently fails, there
is no alternative other than leaking the memory.
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The single atomic pool is allocated from the lowest zone possible since
it is guaranteed to be applicable for any DMA allocation.
Devices may allocate through the DMA API but not have a strict reliance
on GFP_DMA memory. Since the atomic pool will be used for all
non-blockable allocations, returning all memory from ZONE_DMA may
unnecessarily deplete the zone.
Provision for multiple atomic pools that will map to the optimal gfp
mask of the device.
When allocating non-blockable memory, determine the optimal gfp mask of
the device and use the appropriate atomic pool.
The coherent DMA mask will remain the same between allocation and free
and, thus, memory will be freed to the same atomic pool it was allocated
from.
__dma_atomic_pool_init() will be changed to return struct gen_pool *
later once dynamic expansion is added.
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The upper 32-bit physical address gets truncated inadvertently
when dma_direct_get_required_mask() invokes phys_to_dma_direct().
This results in dma_addressing_limited() return incorrect value
when used in platforms with LPAE enabled.
Fix it here by explicitly type casting 'max_pfn' to phys_addr_t
in order to prevent overflow of intermediate value while evaluating
'(max_pfn - 1) << PAGE_SHIFT'.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
- fix an integer overflow in the coherent pool (Kevin Grandemange)
- provide support for in-place uncached remapping and use that
for openrisc
- fix the arm coherent allocator to take the bus limit into account
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Merge tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- fix an integer overflow in the coherent pool (Kevin Grandemange)
- provide support for in-place uncached remapping and use that for
openrisc
- fix the arm coherent allocator to take the bus limit into account
* tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping:
ARM/dma-mapping: merge __dma_supported into arm_dma_supported
ARM/dma-mapping: take the bus limit into account in __dma_alloc
ARM/dma-mapping: remove get_coherent_dma_mask
openrisc: use the generic in-place uncached DMA allocator
dma-direct: provide a arch_dma_clear_uncached hook
dma-direct: make uncached_kernel_address more general
dma-direct: consolidate the error handling in dma_direct_alloc_pages
dma-direct: remove the cached_kernel_address hook
dma-coherent: fix integer overflow in the reserved-memory dma allocation
This allows the arch code to reset the page tables to cached access when
freeing a dma coherent allocation that was set to uncached using
arch_dma_set_uncached.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Rename the symbol to arch_dma_set_uncached, and pass a size to it as
well as allow an error return. That will allow reusing this hook for
in-place pagetable remapping.
As the in-place remap doesn't always require an explicit cache flush,
also detangle ARCH_HAS_DMA_PREP_COHERENT from ARCH_HAS_DMA_SET_UNCACHED.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Remove the unset dma_mask case as that won't get into mapping calls
anymore, and also report the other errors unconditonally and with a
slightly improved message. Remove the now pointless report_addr helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad@darnok.org>
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>
dma_direct_supported tries to find the minimum addressable bitmask
based on the end pfn and optional magic that architectures can use
to communicate the size of the magic ZONE_DMA that can be used
for bounce buffering. But between the DMA offsets that can change
per device (or sometimes even region), the fact the ZONE_DMA isn't
even guaranteed to be the lowest addresses and failure of having
proper interfaces to the MM code this fails at least for one
arm subarchitecture.
As all the legacy DMA implementations have supported 32-bit DMA
masks, and 32-bit masks are guranteed to always work by the API
contract (using bounce buffers if needed), we can short cut the
complicated check and always return true without breaking existing
assumptions. Hopefully we can properly clean up the interaction
with the arch defined zones and the bootmem allocator eventually.
Fixes: ad3c7b18c5 ("arm: use swiotlb for bounce buffering on LPAE configs")
Reported-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Using a mask to represent bus DMA constraints has a set of limitations.
The biggest one being it can only hold a power of two (minus one). The
DMA mapping code is already aware of this and treats dev->bus_dma_mask
as a limit. This quirk is already used by some architectures although
still rare.
With the introduction of the Raspberry Pi 4 we've found a new contender
for the use of bus DMA limits, as its PCIe bus can only address the
lower 3GB of memory (of a total of 4GB). This is impossible to represent
with a mask. To make things worse the device-tree code rounds non power
of two bus DMA limits to the next power of two, which is unacceptable in
this case.
In the light of this, rename dev->bus_dma_mask to dev->bus_dma_limit all
over the tree and treat it as such. Note that dev->bus_dma_limit should
contain the higher accessible DMA address.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The valid memory address check in dma_capable only makes sense when mapping
normal memory, not when using dma_map_resource to map a device resource.
Add a new boolean argument to dma_capable to exclude that check for the
dma_map_resource case.
Fixes: b12d66278d ("dma-direct: check for overflows on 32 bit DMA addresses")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
When mapping resources we can't just use swiotlb ram for bounce
buffering. Switch to a direct dma_capable check instead.
Fixes: cfced78696 ("dma-mapping: remove the default map_resource implementation")
Reported-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
These are pure cache maintainance routines, so drop the unused
struct device argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Integrate the generic dma remapping implementation into the main flow.
This prepares for architectures like xtensa that use an uncached
segment for pages in the kernel mapping, but can also remap highmem
from CMA. To simplify that implementation we now always deduct the
page from the physical address via the DMA address instead of the
virtual address.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
For dma-direct we know that the DMA address is an encoding of the
physical address that we can trivially decode. Use that fact to
provide implementations that do not need the arch_dma_coherent_to_pfn
architecture hook. Note that we still can only support mmap of
non-coherent memory only if the architecture provides a way to set an
uncached bit in the page tables. This must be true for architectures
that use the generic remap helpers, but other architectures can also
manually select it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
We can just call dma_free_contiguous directly instead of wrapping it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
Some architectures, notably ARM, are interested in tweaking this
depending on their runtime DMA addressing limitations.
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.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>
The new dma_alloc_contiguous hides if we allocate CMA or regular
pages, and thus fails to retry a ZONE_NORMAL allocation if the CMA
allocation succeeds but isn't addressable. That means we either fail
outright or dip into a small zone that might not succeed either.
Thanks to Hillf Danton for debugging this issue.
Fixes: b1d2dc009d ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers")
Reported-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Randy Dunlap
Christoph Hellwig
Jim Quinlan
Nicolas Saenz Julienne
Linus Torvalds
David Rientjes
Kishon Vijay Abraham I
Joerg Roedel
Lu Baolu