Commit Graph

249 Commits

Author SHA1 Message Date
Christoph Hellwig
3d842b51a0 dma-mapping: remove the dma_dummy_ops export
dma_dummy_ops is only used by the ACPI code, which can't be modular.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-09-11 08:13:03 +02:00
Barry Song
2281f797f5 mm: cma: use CMA_MAX_NAME to define the length of cma name array
CMA_MAX_NAME should be visible to CMA's users as they might need it to set
the name of CMA areas and avoid hardcoding the size locally.
So this patch moves CMA_MAX_NAME from local header file to include/linux
header file and removes the hardcode in both hugetlb.c and contiguous.c.

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-01 09:19:43 +02:00
Barry Song
b7176c261c dma-contiguous: provide the ability to reserve per-numa CMA
Right now, drivers like ARM SMMU are using dma_alloc_coherent() to get
coherent DMA buffers to save their command queues and page tables. As
there is only one default CMA in the whole system, SMMUs on nodes other
than node0 will get remote memory. This leads to significant latency.

This patch provides per-numa CMA so that drivers like SMMU can get local
memory. Tests show localizing CMA can decrease dma_unmap latency much.
For instance, before this patch, SMMU on node2  has to wait for more than
560ns for the completion of CMD_SYNC in an empty command queue; with this
patch, it needs 240ns only.

A positive side effect of this patch would be improving performance even
further for those users who are worried about performance more than DMA
security and use iommu.passthrough=1 to skip IOMMU. With local CMA, all
drivers can get local coherent DMA buffers.

Also, this patch changes the default CONFIG_CMA_AREAS to 19 in NUMA. As
1+CONFIG_CMA_AREAS should be quite enough for most servers on the market
even they enable both hugetlb_cma and pernuma_cma.
2 numa nodes: 2(hugetlb) + 2(pernuma) + 1(default global cma) = 5
4 numa nodes: 4(hugetlb) + 4(pernuma) + 1(default global cma) = 9
8 numa nodes: 8(hugetlb) + 8(pernuma) + 1(default global cma) = 17

Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-09-01 09:19:28 +02:00
Dan Carpenter
892fc9f683 dma-pool: Fix an uninitialized variable bug in atomic_pool_expand()
The "page" pointer can be used with out being initialized.

Fixes: d7e673ec2c ("dma-pool: Only allocate from CMA when in same memory zone")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-08-27 09:22:56 +02:00
Linus Torvalds
d271b51c60 dma-mapping fixes for 5.9
- fix out more fallout from the dma-pool changes
    (Nicolas Saenz Julienne, me)
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Merge tag 'dma-mapping-5.9-1' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:
 "Fix more fallout from the dma-pool changes (Nicolas Saenz Julienne,
  me)"

* tag 'dma-mapping-5.9-1' of git://git.infradead.org/users/hch/dma-mapping:
  dma-pool: Only allocate from CMA when in same memory zone
  dma-pool: fix coherent pool allocations for IOMMU mappings
2020-08-20 10:48:17 -07:00
Linus Torvalds
5bbec3cfe3 Cleanup, SECCOMP_FILTER support, message printing fixes, and other
changes to arch/sh.
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Merge tag 'sh-for-5.9' of git://git.libc.org/linux-sh

Pull arch/sh updates from Rich Felker:
 "Cleanup, SECCOMP_FILTER support, message printing fixes, and other
  changes to arch/sh"

* tag 'sh-for-5.9' of git://git.libc.org/linux-sh: (34 commits)
  sh: landisk: Add missing initialization of sh_io_port_base
  sh: bring syscall_set_return_value in line with other architectures
  sh: Add SECCOMP_FILTER
  sh: Rearrange blocks in entry-common.S
  sh: switch to copy_thread_tls()
  sh: use the generic dma coherent remap allocator
  sh: don't allow non-coherent DMA for NOMMU
  dma-mapping: consolidate the NO_DMA definition in kernel/dma/Kconfig
  sh: unexport register_trapped_io and match_trapped_io_handler
  sh: don't include <asm/io_trapped.h> in <asm/io.h>
  sh: move the ioremap implementation out of line
  sh: move ioremap_fixed details out of <asm/io.h>
  sh: remove __KERNEL__ ifdefs from non-UAPI headers
  sh: sort the selects for SUPERH alphabetically
  sh: remove -Werror from Makefiles
  sh: Replace HTTP links with HTTPS ones
  arch/sh/configs: remove obsolete CONFIG_SOC_CAMERA*
  sh: stacktrace: Remove stacktrace_ops.stack()
  sh: machvec: Modernize printing of kernel messages
  sh: pci: Modernize printing of kernel messages
  ...
2020-08-15 18:50:32 -07:00
Christoph Hellwig
846f9e1fb9 dma-mapping: consolidate the NO_DMA definition in kernel/dma/Kconfig
Have a single definition that architetures can select.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rich Felker <dalias@libc.org>
2020-08-14 22:05:17 -04:00
Linus Torvalds
5848dc5b1b dma-debug: remove debug_dma_assert_idle() function
This remoes the code from the COW path to call debug_dma_assert_idle(),
which was added many years ago.

Google shows that it hasn't caught anything in the 6+ years we've had it
apart from a false positive, and Hugh just noticed how it had a very
unfortunate spinlock serialization in the COW path.

He fixed that issue the previous commit (a85ffd59bd36: "dma-debug: fix
debug_dma_assert_idle(), use rcu_read_lock()"), but let's see if anybody
even notices when we remove this function entirely.

NOTE! We keep the dma tracking infrastructure that was added by the
commit that introduced it.  Partly to make it easier to resurrect this
debug code if we ever deside to, and partly because that tracking by pfn
and offset looks quite reasonable.

The problem with this debug code was simply that it was expensive and
didn't seem worth it, not that it was wrong per se.

Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 15:22:43 -07:00
Hugh Dickins
a85ffd59bd dma-debug: fix debug_dma_assert_idle(), use rcu_read_lock()
Since commit 2a9127fcf2 ("mm: rewrite wait_on_page_bit_common()
logic") improved unlock_page(), it has become more noticeable how
cow_user_page() in a kernel with CONFIG_DMA_API_DEBUG=y can create and
suffer from heavy contention on DMA debug's radix_lock in
debug_dma_assert_idle().

It is only doing a lookup: use rcu_read_lock() and rcu_read_unlock()
instead; though that does require the static ents[] to be moved
onstack...

...but, hold on, isn't that radix_tree_gang_lookup() and loop doing
quite the wrong thing: searching CACHELINES_PER_PAGE entries for an
exact match with the first cacheline of the page in question?
radix_tree_gang_lookup() is the right tool for the job, but we need
nothing more than to check the first entry it can find, reporting if
that falls anywhere within the page.

(Is RCU safe here? As safe as using the spinlock was. The entries are
never freed, so don't need to be freed by RCU. They may be reused, and
there is a faint chance of a race, with an offending entry reused while
printing its error info; but the spinlock did not prevent that either,
and I agree that it's not worth worrying about. ]

[ Side noe: this patch is a clear improvement to the status quo, but the
  next patch will be removing this debug function entirely.

  But just in case we decide we want to resurrect the debugging code
  some day, I'm first applying this improvement patch so that it doesn't
  get lost    - Linus ]

Fixes: 3b7a6418c7 ("dma debug: account for cachelines and read-only mappings in overlap tracking")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-14 15:16:03 -07:00
Nicolas Saenz Julienne
d7e673ec2c dma-pool: Only allocate from CMA when in same memory zone
There is no guarantee to CMA's placement, so allocating a zone specific
atomic pool from CMA might return memory from a completely different
memory zone. To get around this double check CMA's placement before
allocating from it.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-08-14 16:27:05 +02:00
Christoph Hellwig
9420139f51 dma-pool: fix coherent pool allocations for IOMMU mappings
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>
2020-08-14 16:27:00 +02:00
Linus Torvalds
2324d50d05 It's been a busy cycle for documentation - hopefully the busiest for a
while to come.  Changes include:
 
  - Some new Chinese translations
 
  - Progress on the battle against double words words and non-HTTPS URLs
 
  - Some block-mq documentation
 
  - More RST conversions from Mauro.  At this point, that task is
    essentially complete, so we shouldn't see this kind of churn again for a
    while.  Unless we decide to switch to asciidoc or something...:)
 
  - Lots of typo fixes, warning fixes, and more.
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Merge tag 'docs-5.9' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "It's been a busy cycle for documentation - hopefully the busiest for a
  while to come. Changes include:

   - Some new Chinese translations

   - Progress on the battle against double words words and non-HTTPS
     URLs

   - Some block-mq documentation

   - More RST conversions from Mauro. At this point, that task is
     essentially complete, so we shouldn't see this kind of churn again
     for a while. Unless we decide to switch to asciidoc or
     something...:)

   - Lots of typo fixes, warning fixes, and more"

* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
  scripts/kernel-doc: optionally treat warnings as errors
  docs: ia64: correct typo
  mailmap: add entry for <alobakin@marvell.com>
  doc/zh_CN: add cpu-load Chinese version
  Documentation/admin-guide: tainted-kernels: fix spelling mistake
  MAINTAINERS: adjust kprobes.rst entry to new location
  devices.txt: document rfkill allocation
  PCI: correct flag name
  docs: filesystems: vfs: correct flag name
  docs: filesystems: vfs: correct sync_mode flag names
  docs: path-lookup: markup fixes for emphasis
  docs: path-lookup: more markup fixes
  docs: path-lookup: fix HTML entity mojibake
  CREDITS: Replace HTTP links with HTTPS ones
  docs: process: Add an example for creating a fixes tag
  doc/zh_CN: add Chinese translation prefer section
  doc/zh_CN: add clearing-warn-once Chinese version
  doc/zh_CN: add admin-guide index
  doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
  futex: MAINTAINERS: Re-add selftests directory
  ...
2020-08-04 22:47:54 -07:00
Linus Torvalds
2ed90dbbf7 dma-mapping updates for 5.9
- make support for dma_ops optional
  - move more code out of line
  - add generic support for a dma_ops bypass mode
  - misc cleanups
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Merge tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - make support for dma_ops optional

 - move more code out of line

 - add generic support for a dma_ops bypass mode

 - misc cleanups

* tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mapping:
  dma-contiguous: cleanup dma_alloc_contiguous
  dma-debug: use named initializers for dir2name
  powerpc: use the generic dma_ops_bypass mode
  dma-mapping: add a dma_ops_bypass flag to struct device
  dma-mapping: make support for dma ops optional
  dma-mapping: inline the fast path dma-direct calls
  dma-mapping: move the remaining DMA API calls out of line
2020-08-04 17:29:57 -07:00
Linus Torvalds
99ea1521a0 Remove uninitialized_var() macro for v5.9-rc1
- Clean up non-trivial uses of uninitialized_var()
 - Update documentation and checkpatch for uninitialized_var() removal
 - Treewide removal of uninitialized_var()
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Merge tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull uninitialized_var() macro removal from Kees Cook:
 "This is long overdue, and has hidden too many bugs over the years. The
  series has several "by hand" fixes, and then a trivial treewide
  replacement.

   - Clean up non-trivial uses of uninitialized_var()

   - Update documentation and checkpatch for uninitialized_var() removal

   - Treewide removal of uninitialized_var()"

* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  compiler: Remove uninitialized_var() macro
  treewide: Remove uninitialized_var() usage
  checkpatch: Remove awareness of uninitialized_var() macro
  mm/debug_vm_pgtable: Remove uninitialized_var() usage
  f2fs: Eliminate usage of uninitialized_var() macro
  media: sur40: Remove uninitialized_var() usage
  KVM: PPC: Book3S PR: Remove uninitialized_var() usage
  clk: spear: Remove uninitialized_var() usage
  clk: st: Remove uninitialized_var() usage
  spi: davinci: Remove uninitialized_var() usage
  ide: Remove uninitialized_var() usage
  rtlwifi: rtl8192cu: Remove uninitialized_var() usage
  b43: Remove uninitialized_var() usage
  drbd: Remove uninitialized_var() usage
  x86/mm/numa: Remove uninitialized_var() usage
  docs: deprecated.rst: Add uninitialized_var()
2020-08-04 13:49:43 -07:00
Christoph Hellwig
274b3f7bf3 dma-contiguous: cleanup dma_alloc_contiguous
Split out a cma_alloc_aligned helper to deal with the "interesting"
calling conventions for cma_alloc, which then allows to the main
function to be written straight forward.  This also takes advantage
of the fact that NULL dev arguments have been gone from the DMA API
for a while.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Barry Song <song.bao.hua@hisilicon.com>
2020-07-28 13:42:15 +02:00
Christoph Hellwig
23efed6fa7 dma-debug: use named initializers for dir2name
Make dir2name a little more readable and maintainable by using
named initializers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-07-19 09:31:13 +02:00
Christoph Hellwig
d35834c648 dma-mapping: add a dma_ops_bypass flag to struct device
Several IOMMU drivers have a bypass mode where they can use a direct
mapping if the devices DMA mask is large enough.  Add generic support
to the core dma-mapping code to do that to switch those drivers to
a common solution.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2020-07-19 09:29:29 +02:00
Christoph Hellwig
2f9237d4f6 dma-mapping: make support for dma ops optional
Avoid the overhead of the dma ops support for tiny builds that only
use the direct mapping.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2020-07-19 09:29:23 +02:00
Kees Cook
3f649ab728 treewide: Remove uninitialized_var() usage
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.

In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:

git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
	xargs perl -pi -e \
		's/\buninitialized_var\(([^\)]+)\)/\1/g;
		 s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'

drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.

No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.

[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/

Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-07-16 12:35:15 -07:00
Christoph Hellwig
b417417300 dma-mapping: inline the fast path dma-direct calls
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>
2020-07-16 16:58:37 +02:00
Christoph Hellwig
d3fa60d7bf dma-mapping: move the remaining DMA API calls out of line
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>
2020-07-16 16:58:33 +02:00
Nicolas Saenz Julienne
d9765e41d8 dma-pool: do not allocate pool memory from CMA
There is no guarantee to CMA's placement, so allocating a zone specific
atomic pool from CMA might return memory from a completely different
memory zone. So stop using it.

Fixes: c84dc6e68a ("dma-pool: add additional coherent pools to map to gfp mask")
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14 15:46:32 +02:00
Nicolas Saenz Julienne
81e9d894e0 dma-pool: make sure atomic pool suits device
When allocating DMA memory from a pool, the core can only guess which
atomic pool will fit a device's constraints. If it doesn't, get a safer
atomic pool and try again.

Fixes: c84dc6e68a ("dma-pool: add additional coherent pools to map to gfp mask")
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14 15:42:33 +02:00
Nicolas Saenz Julienne
48b6703858 dma-pool: introduce dma_guess_pool()
dma-pool's dev_to_pool() creates the false impression that there is a
way to grantee a mapping between a device's DMA constraints and an
atomic pool. It tuns out it's just a guess, and the device might need to
use an atomic pool containing memory from a 'safer' (or lower) memory
zone.

To help mitigate this, introduce dma_guess_pool() which can be fed a
device's DMA constraints and atomic pools already known to be faulty, in
order for it to provide an better guess on which pool to use.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14 15:42:30 +02:00
Nicolas Saenz Julienne
23e469be62 dma-pool: get rid of dma_in_atomic_pool()
The function is only used once and can be simplified to a one-liner.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14 15:42:27 +02:00
Nicolas Saenz Julienne
567f6a6eba dma-direct: provide function to check physical memory area validity
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>
2020-07-14 15:42:24 +02:00
Linus Torvalds
5a764898af Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
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
  ...
2020-07-10 18:16:22 -07:00
David S. Miller
e708e2bd55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2020-06-30

The following pull-request contains BPF updates for your *net* tree.

We've added 28 non-merge commits during the last 9 day(s) which contain
a total of 35 files changed, 486 insertions(+), 232 deletions(-).

The main changes are:

1) Fix an incorrect verifier branch elimination for PTR_TO_BTF_ID pointer
   types, from Yonghong Song.

2) Fix UAPI for sockmap and flow_dissector progs that were ignoring various
   arguments passed to BPF_PROG_{ATTACH,DETACH}, from Lorenz Bauer & Jakub Sitnicki.

3) Fix broken AF_XDP DMA hacks that are poking into dma-direct and swiotlb
   internals and integrate it properly into DMA core, from Christoph Hellwig.

4) Fix RCU splat from recent changes to avoid skipping ingress policy when
   kTLS is enabled, from John Fastabend.

5) Fix BPF ringbuf map to enforce size to be the power of 2 in order for its
   position masking to work, from Andrii Nakryiko.

6) Fix regression from CAP_BPF work to re-allow CAP_SYS_ADMIN for loading
   of network programs, from Maciej Żenczykowski.

7) Fix libbpf section name prefix for devmap progs, from Jesper Dangaard Brouer.

8) Fix formatting in UAPI documentation for BPF helpers, from Quentin Monnet.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-30 14:20:45 -07:00
Christoph Hellwig
3aa9162500 dma-mapping: Add a new dma_need_sync API
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
2020-06-30 15:44:03 +02:00
David Rientjes
71cdec4fab dma-mapping: warn when coherent pool is depleted
When a DMA coherent pool is depleted, allocation failures may or may not
get reported in the kernel log depending on the allocator.

The admin does have a workaround, however, by using coherent_pool= on the
kernel command line.

Provide some guidance on the failure and a recommended minimum size for
the pools (double the size).

Signed-off-by: David Rientjes <rientjes@google.com>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-06-29 10:05:21 +02:00
Mauro Carvalho Chehab
985098a05e docs: fix references for DMA*.txt files
As we moved those files to core-api, fix references to point
to their newer locations.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/37b2fd159fbc7655dbf33b3eb1215396a25f6344.1592895969.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-06-26 10:01:32 -06:00
Eric Auger
8e36baf97b dma-remap: align the size in dma_common_*_remap()
Running a guest with a virtio-iommu protecting virtio devices
is broken since commit 515e5b6d90 ("dma-mapping: use vmap insted
of reimplementing it"). Before the conversion, the size was
page aligned in __get_vm_area_node(). Doing so fixes the
regression.

Fixes: 515e5b6d90 ("dma-mapping: use vmap insted of reimplementing it")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-06-23 14:14:41 +02:00
Christoph Hellwig
d07ae4c486 dma-mapping: DMA_COHERENT_POOL should select GENERIC_ALLOCATOR
The dma coherent pool code needs genalloc.  Move the select over
from DMA_REMAP, which doesn't actually need it.

Fixes: dbed452a07 ("dma-pool: decouple DMA_REMAP from DMA_COHERENT_POOL")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Rientjes <rientjes@google.com>
2020-06-23 14:13:58 +02:00
David Rientjes
1a2b3357e8 dma-direct: add missing set_memory_decrypted() for coherent mapping
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>
2020-06-23 14:13:54 +02:00
David Rientjes
56fccf21d1 dma-direct: check return value when encrypting or decrypting memory
__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>
2020-06-17 09:29:38 +02:00
David Rientjes
96a539fa3b dma-direct: re-encrypt memory if dma_direct_alloc_pages() fails
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>
2020-06-17 09:29:38 +02:00
David Rientjes
633d5fce78 dma-direct: always align allocation size in dma_direct_alloc_pages()
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>
2020-06-17 09:29:38 +02:00
Christoph Hellwig
26749b3201 dma-direct: mark __dma_direct_alloc_pages static
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-06-17 09:29:37 +02:00
Christoph Hellwig
1fbf57d053 dma-direct: re-enable mmap for !CONFIG_MMU
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>
2020-06-17 09:29:31 +02:00
David Rientjes
dbed452a07 dma-pool: decouple DMA_REMAP from DMA_COHERENT_POOL
DMA_REMAP is an unnecessary requirement for AMD SEV, which requires
DMA_COHERENT_POOL, so avoid selecting it when it is otherwise unnecessary.

The only other requirement for DMA coherent pools is DMA_DIRECT_REMAP, so
ensure that properly selects the config option when needed.

Fixes: 82fef0ad81 ("x86/mm: unencrypted non-blocking DMA allocations use coherent pools")
Reported-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: David Rientjes <rientjes@google.com>
Tested-by: Alex Xu (Hello71) <alex_y_xu@yahoo.ca>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-06-15 08:35:30 +02:00
Geert Uytterhoeven
3ee06a6d53 dma-pool: fix too large DMA pools on medium memory size systems
On systems with at least 32 MiB, but less than 32 GiB of RAM, the DMA
memory pools are much larger than intended (e.g. 2 MiB instead of 128
KiB on a 256 MiB system).

Fix this by correcting the calculation of the number of GiBs of RAM in
the system.  Invert the order of the min/max operations, to keep on
calculating in pages until the last step, which aids readability.

Fixes: 1d659236fb ("dma-pool: scale the default DMA coherent pool size with memory capacity")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-06-09 15:25:52 +02:00
Linus Torvalds
1ee18de929 dma-mapping updates for 5.8, part 1
- enhance the dma pool to allow atomic allocation on x86 with AMD SEV
    (David Rientjes)
  - two small cleanups (Jason Yan and Peter Collingbourne)
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Merge tag 'dma-mapping-5.8' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping updates from Christoph Hellwig:

 - enhance the dma pool to allow atomic allocation on x86 with AMD SEV
   (David Rientjes)

 - two small cleanups (Jason Yan and Peter Collingbourne)

* tag 'dma-mapping-5.8' of git://git.infradead.org/users/hch/dma-mapping:
  dma-contiguous: fix comment for dma_release_from_contiguous
  dma-pool: scale the default DMA coherent pool size with memory capacity
  x86/mm: unencrypted non-blocking DMA allocations use coherent pools
  dma-pool: add pool sizes to debugfs
  dma-direct: atomic allocations must come from atomic coherent pools
  dma-pool: dynamically expanding atomic pools
  dma-pool: add additional coherent pools to map to gfp mask
  dma-remap: separate DMA atomic pools from direct remap code
  dma-debug: make __dma_entry_alloc_check_leak() static
2020-06-06 11:43:23 -07:00
Christoph Hellwig
515e5b6d90 dma-mapping: use vmap insted of reimplementing it
Replace the open coded instance of vmap with the actual function.  In
the non-contiguous (IOMMU) case this requires an extra find_vm_area,
but given that this isn't a fast path function that is a small price
to pay.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-6-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:10 -07:00
Peter Collingbourne
298f3db6ee dma-contiguous: fix comment for dma_release_from_contiguous
Commit 90ae409f9e ("dma-direct: fix zone selection
after an unaddressable CMA allocation") changed the logic in
dma_release_from_contiguous to remove the normal pages fallback path,
but did not update the comment. Fix that.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-25 13:17:06 +02:00
David Rientjes
1d659236fb dma-pool: scale the default DMA coherent pool size with memory capacity
When AMD memory encryption is enabled, some devices may use more than
256KB/sec from the atomic pools.  It would be more appropriate to scale
the default size based on memory capacity unless the coherent_pool
option is used on the kernel command line.

This provides a slight optimization on initial expansion and is deemed
appropriate due to the increased reliance on the atomic pools.  Note that
the default size of 128KB per pool will normally be larger than the
single coherent pool implementation since there are now up to three
coherent pools (DMA, DMA32, and kernel).

Note that even prior to this patch, coherent_pool= for sizes larger than
1 << (PAGE_SHIFT + MAX_ORDER-1) can fail.  With new dynamic expansion
support, this would be trivially extensible to allow even larger initial
sizes.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-25 13:17:06 +02:00
David Rientjes
2edc5bb3c5 dma-pool: add pool sizes to debugfs
The atomic DMA pools can dynamically expand based on non-blocking
allocations that need to use it.

Export the sizes of each of these pools, in bytes, through debugfs for
measurement.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Rientjes <rientjes@google.com>
[hch: remove the !CONFIG_DEBUG_FS stubs]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-25 13:17:05 +02:00
David Rientjes
76a19940bd dma-direct: atomic allocations must come from atomic coherent pools
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>
2020-04-25 13:17:05 +02:00
David Rientjes
54adadf9b0 dma-pool: dynamically expanding atomic pools
When an atomic pool becomes fully depleted because it is now relied upon
for all non-blocking allocations through the DMA API, allow background
expansion of each pool by a kworker.

When an atomic pool has less than the default size of memory left, kick
off a kworker to dynamically expand the pool in the background.  The pool
is doubled in size, up to MAX_ORDER-1.  If memory cannot be allocated at
the requested order, smaller allocation(s) are attempted.

This allows the default size to be kept quite low when one or more of the
atomic pools is not used.

Allocations for lowmem should also use GFP_KERNEL for the benefits of
reclaim, so use GFP_KERNEL | GFP_DMA and GFP_KERNEL | GFP_DMA32 for
lowmem allocations.

This also allows __dma_atomic_pool_init() to return a pointer to the pool
to make initialization cleaner.

Also switch over some node ids to the more appropriate NUMA_NO_NODE.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-25 13:17:02 +02:00
David Rientjes
c84dc6e68a dma-pool: add additional coherent pools to map to gfp mask
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>
2020-04-20 12:09:40 +02:00
David Rientjes
e860c299ac dma-remap: separate DMA atomic pools from direct remap code
DMA atomic pools will be needed beyond only CONFIG_DMA_DIRECT_REMAP so
separate them out into their own file.

This also adds a new Kconfig option that can be subsequently used for
options, such as CONFIG_AMD_MEM_ENCRYPT, that will utilize the coherent
pools but do not have a dependency on direct remapping.

For this patch alone, there is no functional change introduced.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Rientjes <rientjes@google.com>
[hch: fixup copyrights and remove unused includes]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-20 12:08:45 +02:00