This way we have one central definition of it, and user can select it as
needed.  The new option is not user visible, which is the behavior
it had in most architectures, with a few notable exceptions:

 - On x86_64 and mips/loongson3 it used to be user selectable, but
   defaulted to y.  It now is unconditional, which seems like the right
   thing for 64-bit architectures without guaranteed availablity of
   IOMMUs.
 - on powerpc the symbol is user selectable and defaults to n, but
   many boards select it.  This change assumes no working setup
   required a manual selection, but if that turned out to be wrong
   we'll have to add another select statement or two for the respective
   boards.
Signed-off-by: Christoph Hellwig <hch@lst.de>

Only mips and unicore32 select CONFIG_NEED_SG_DMA_LENGTH when building
swiotlb.  swiotlb itself never merges segements and doesn't accesses the
dma_length field directly, so drop the dependency.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: James Hogan <jhogan@kernel.org>

swiotlb is only used as a library of helper for xen-swiotlb if Xen support
is enabled on arm, so don't build it by default.
Signed-off-by: Christoph Hellwig <hch@lst.de>

This symbol is now always identical to CONFIG_ARCH_DMA_ADDR_T_64BIT, so
remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>

Define this symbol if the architecture either uses 64-bit pointers or the
PHYS_ADDR_T_64BIT is set.  This covers 95% of the old arch magic.  We only
need an additional select for Xen on ARM (why anyway?), and we now always
set ARCH_DMA_ADDR_T_64BIT on mips boards with 64-bit physical addressing
instead of only doing it when highmem is set.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: James Hogan <jhogan@kernel.org>

Instead select the PHYS_ADDR_T_64BIT for 32-bit architectures that need a
64-bit phys_addr_t type directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: James Hogan <jhogan@kernel.org>

This way we have one central definition of it, and user can select it as
needed.  Note that we now also always select it when CONFIG_DMA_API_DEBUG
is select, which fixes some incorrect checks in a few network drivers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>

This way we have one central definition of it, and user can select it as
needed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>

This way we have one central definition of it, and user can select it as
needed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>

This avoids selecting IOMMU_HELPER just for this function.  And we only
use it once or twice in normal builds so this often even is a size
reduction.
Signed-off-by: Christoph Hellwig <hch@lst.de>

This function is only used by built-in code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>

This code is only used by sparc, and all new iommu drivers should use the
drivers/iommu/ framework.  Also remove the unused exports.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>

There is no arch specific code required for dma-debug, so there is no
need to opt into the support either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

Only used by the AMD GART and Intel VT-D drivers, which must be built in.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

Just keep a single variable with a descriptive name instead of two
with confusing names.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

Most mainstream architectures are using 65536 entries, so lets stick to
that.  If someone is really desperate to override it that can still be
done through <asm/dma-mapping.h>, but I'd rather see a really good
rationale for that.

dma_debug_init is now called as a core_initcall, which for many
architectures means much earlier, and provides dma-debug functionality
earlier in the boot process.  This should be safe as it only relies
on the memory allocator already being available.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>

This was used by the ide, scsi and networking code in the past to
determine if they should bounce payloads.  Now that the dma mapping
always have to support dma to all physical memory (thanks to swiotlb
for non-iommu systems) there is no need to this crude hack any more.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Palmer Dabbelt <palmer@sifive.com> (for riscv)
Reviewed-by: Jens Axboe <axboe@kernel.dk>

These days the dma mapping routines must be able to handle any address
supported by the device, be that using an iommu, or swiotlb if none is
supported.  With that the PCI_DMA_BUS_IS_PHYS check in illegal_highdma
is not needed and can be removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>

We now have ways to deal with drainage in the block layer, and libata has
been using it for ages.  We also want to get rid of PCI_DMA_BUS_IS_PHYS
now, so just reduce the PCI transfer size for ide - anyone who cares for
performance on PCI controllers should have switched to libata long ago.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>

ide_toggle_bounce did select various strange block bounce limits, including
not bouncing at all as soon as an iommu is present in the system.  Given
that the dma_map routines now handle any required bounce buffering except
for ISA DMA, and the ide code already must handle either ISA DMA or highmem
at least for iommu equipped systems we can get rid of the block layer
bounce limit setting entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>

We can rely on the dma-mapping code to handle any DMA limits that is
bigger than the ISA DMA mask for us (either using an iommu or swiotlb),
so remove setting the block layer bounce limit for anything but the
unchecked_isa_dma case, or the bouncing for highmem pages.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>

As the recent swiotlb bug revealed, we seem to have given up the direct
DMA allocation too early and felt back to swiotlb allocation.  The reason
is that swiotlb allocator expected that dma_direct_alloc() would try
harder to get pages even below 64bit DMA mask with GFP_DMA32, but the
function doesn't do that but only deals with GFP_DMA case.

This patch adds a similar fallback reallocation with GFP_DMA32 as we've
done with GFP_DMA.  The condition is that the coherent mask is smaller
than 64bit (i.e. some address limitation), and neither GFP_DMA nor
GFP_DMA32 is set beforehand.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Smatch complains here:

    lib/swiotlb.c:730 swiotlb_alloc_buffer()
    warn: variable dereferenced before check 'dev' (see line 716)

"dev" isn't ever NULL in this function so we can just remove the check.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

With each bus implementing its own DMA configuration callback, there is no
need for bus to explicitly set the force_dma flag.  Modify the
of_dma_configure function to accept an input parameter which specifies if
implicit DMA configuration is required when it is not described by the
firmware.
Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>  # PCI parts
Reviewed-by: Rob Herring <robh@kernel.org>
[hch: tweaked the changelog a bit]
Signed-off-by: Christoph Hellwig <hch@lst.de>

ACPI/OF support for configuration of DMA is a bus specific aspect, and
thus should be configured by the bus.  Introduces a 'dma_configure' bus
method so that busses can control their DMA capabilities.

Also update the PCI, Platform, ACPI and host1x buses to use the new
method.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nipun Gupta <nipun.gupta@nxp.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>  # PCI parts
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[hch: simplified host1x_dma_configure based on a comment from Thierry,
      rewrote changelog]
Signed-off-by: Christoph Hellwig <hch@lst.de>

The result was printing the warning only when we were explicitly asked
not to.

Cc: stable@vger.kernel.org
Fixes: 0176adb0 "swiotlb: refactor
 coherent buffer allocation"
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de>

Pull hexagon fixes from Richard Kuo:
 "Some small fixes for module compilation"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rkuo/linux-hexagon-kernel:
  hexagon: export csum_partial_copy_nocheck
  hexagon: add memset_io() helper

This is needed to link ipv6 as a loadable module, which in turn happens
in allmodconfig.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Kuo <rkuo@codeaurora.org>

We already have memcpy_toio(), but not memset_io(), so let's
add the obvious version to allow building an allmodconfig kernel
without errors like

drivers/gpu/drm/ttm/ttm_bo_util.c: In function 'ttm_bo_move_memcpy':
drivers/gpu/drm/ttm/ttm_bo_util.c:390:3: error: implicit declaration of function 'memset_io' [-Werror=implicit-function-declaration]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Kuo <rkuo@codeaurora.org>

Pull xfs fixes from Darrick Wong:
 "Here are a few more bug fixes for xfs for 4.17-rc4. Most of them are
  fixes for bad behavior.

  This series has been run through a full xfstests run during LSF and
  through a quick xfstests run against this morning's master, with no
  major failures reported.

  Summary:

   - Enhance inode fork verifiers to prevent loading of corrupted
     metadata.

   - Fix a crash when we try to convert extents format inodes to btree
     format, we run out of space, but forget to revert the in-core state
     changes.

   - Fix file size checks when doing INSERT_RANGE that could cause files
     to end up negative size if there previously was an extent mapped at
     s_maxbytes.

   - Fix a bug when doing a remove-then-add ATTR_REPLACE xattr update
     where we forget to clear ATTR_REPLACE after the remove, which
     causes the attr to be lost and the fs to shut down due to (what it
     thinks is) inconsistent in-core state"

* tag 'xfs-4.17-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: don't fail when converting shortform attr to long form during ATTR_REPLACE
  xfs: prevent creating negative-sized file via INSERT_RANGE
  xfs: set format back to extents if xfs_bmap_extents_to_btree
  xfs: enhance dinode verifier

Pull errseq infrastructure fix from Jeff Layton:
 "The PostgreSQL developers recently had a spirited discussion about the
  writeback error handling in Linux, and reached out to us about a
  behavoir change to the code that bit them when the errseq_t changes
  were merged.

  When we changed to using errseq_t for tracking writeback errors, we
  lost the ability for an application to see a writeback error that
  occurred before the open on which the fsync was issued. This was
  problematic for PostgreSQL which offloads fsync calls to a completely
  separate process from the DB writers.

  This patch restores that ability. If the errseq_t value in the inode
  does not have the SEEN flag set, then we just return 0 for the sample.
  That ensures that any recorded error is always delivered at least
  once.

  Note that we might still lose the error if the inode gets evicted from
  the cache before anything can reopen it, but that was the case before
  errseq_t was merged. At LSF/MM we had some discussion about keeping
  inodes with unreported writeback errors around in the cache for longer
  (possibly indefinitely), but that's really a separate problem"

* tag 'errseq-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  errseq: Always report a writeback error once

 - Fixup license text for oradax driver, from Rob Gardner.

 - Release device object with put_device() instead of straight kfree(),
   from Arvind Yadav.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: vio: use put_device() instead of kfree()
  sparc64: Fix mistake in oradax license text

Never directly free @dev after calling device_register(), even
if it returned an error. Always use put_device() to give up the
reference initialized.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The license text in both oradax files mistakenly specifies "version 3" of
the GNU General Public License.  This is corrected to specify "version 2".
Signed-off-by: Rob Gardner <rob.gardner@oracle.com>
Signed-off-by: Jonathan Helman <jonathan.helman@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull x86 fixes from Thomas Gleixner:
 "Another set of x86 related updates:

   - Fix the long broken x32 version of the IPC user space headers which
     was noticed by Arnd Bergman in course of his ongoing y2038 work.
     GLIBC seems to have non broken private copies of these headers so
     this went unnoticed.

   - Two microcode fixlets which address some more fallout from the
     recent modifications in that area:

      - Unconditionally save the microcode patch, which was only saved
        when CPU_HOTPLUG was enabled causing failures in the late
        loading mechanism

      - Make the later loader synchronization finally work under all
        circumstances. It was exiting early and causing timeout failures
        due to a missing synchronization point.

   - Do not use mwait_play_dead() on AMD systems to prevent excessive
     power consumption as the CPU cannot go into deep power states from
     there.

   - Address an annoying sparse warning due to lost type qualifiers of
     the vmemmap and vmalloc base address constants.

   - Prevent reserving crash kernel region on Xen PV as this leads to
     the wrong perception that crash kernels actually work there which
     is not the case. Xen PV has its own crash mechanism handled by the
     hypervisor.

   - Add missing TLB cpuid values to the table to make the printout on
     certain machines correct.

   - Enumerate the new CLDEMOTE instruction

   - Fix an incorrect SPDX identifier

   - Remove stale macros"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ipc: Fix x32 version of shmid64_ds and msqid64_ds
  x86/setup: Do not reserve a crash kernel region if booted on Xen PV
  x86/cpu/intel: Add missing TLB cpuid values
  x86/smpboot: Don't use mwait_play_dead() on AMD systems
  x86/mm: Make vmemmap and vmalloc base address constants unsigned long
  x86/vector: Remove the unused macro FPU_IRQ
  x86/vector: Remove the macro VECTOR_OFFSET_START
  x86/cpufeatures: Enumerate cldemote instruction
  x86/microcode: Do not exit early from __reload_late()
  x86/microcode/intel: Save microcode patch unconditionally
  x86/jailhouse: Fix incorrect SPDX identifier

Pull x86 pti fixes from Thomas Gleixner:
 "A set of updates for the x86/pti related code:

   - Preserve r8-r11 in int $0x80. r8-r11 need to be preserved, but the
     int$80 entry code removed that quite some time ago. Make it correct
     again.

   - A set of fixes for the Global Bit work which went into 4.17 and
     caused a bunch of interesting regressions:

      - Triggering a BUG in the page attribute code due to a missing
        check for early boot stage

      - Warnings in the page attribute code about holes in the kernel
        text mapping which are caused by the freeing of the init code.
        Handle such holes gracefully.

      - Reduce the amount of kernel memory which is set global to the
        actual text and do not incidentally overlap with data.

      - Disable the global bit when RANDSTRUCT is enabled as it
        partially defeats the hardening.

      - Make the page protection setup correct for vma->page_prot
        population again. The adjustment of the protections fell through
        the crack during the Global bit rework and triggers warnings on
        machines which do not support certain features, e.g. NX"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/entry/64/compat: Preserve r8-r11 in int $0x80
  x86/pti: Filter at vma->vm_page_prot population
  x86/pti: Disallow global kernel text with RANDSTRUCT
  x86/pti: Reduce amount of kernel text allowed to be Global
  x86/pti: Fix boot warning from Global-bit setting
  x86/pti: Fix boot problems from Global-bit setting

Pull timer fixes from Thomas Gleixner:
 "Two fixes from the timer departement:

   - Fix a long standing issue in the NOHZ tick code which causes RB
     tree corruption, delayed timers and other malfunctions. The cause
     for this is code which modifies the expiry time of an enqueued
     hrtimer.

   - Revert the CLOCK_MONOTONIC/CLOCK_BOOTTIME unification due to
     regression reports. Seems userspace _is_ relying on the documented
     behaviour despite our hope that it wont"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME
  tick/sched: Do not mess with an enqueued hrtimer

Pull perf fixes from Thomas Gleixner:
 "The perf update contains the following bits:

  x86:
   - Prevent setting freeze_on_smi on PerfMon V1 CPUs to avoid #GP

  perf stat:
   - Keep the '/' event modifier separator in fallback, for example when
     fallbacking from 'cpu/cpu-cycles/' to user level only, where it
     should become 'cpu/cpu-cycles/u' and not 'cpu/cpu-cycles/:u' (Jiri
     Olsa)

   - Fix PMU events parsing rule, improving error reporting for invalid
     events (Jiri Olsa)

   - Disable write_backward and other event attributes for !group events
     in a group, fixing, for instance this group: '{cycles,msr/aperf/}:S'
     that has leader sampling (:S) and where just the 'cycles', the
     leader event, should have the write_backward attribute set, in this
     case it all fails because the PMU where 'msr/aperf/' lives doesn't
     accepts write_backward style sampling (Jiri Olsa)

   - Only fall back group read for leader (Kan Liang)

   - Fix core PMU alias list for x86 platform (Kan Liang)

   - Print out hint for mixed PMU group error (Kan Liang)

   - Fix duplicate PMU name for interval print (Kan Liang)

  Core:
   - Set main kernel end address properly when reading kernel and module
     maps (Namhyung Kim)

  perf mem:
   - Fix incorrect entries and add missing man options (Sangwon Hong)

  s/390:
   - Remove s390 specific strcmp_cpuid_cmp function (Thomas Richter)

   - Adapt 'perf test' case record+probe_libc_inet_pton.sh for s390

   - Fix s390 undefined record__auxtrace_init() return value in 'perf
     record' (Thomas Richter)"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Don't enable freeze-on-smi for PerfMon V1
  perf stat: Fix duplicate PMU name for interval print
  perf evsel: Only fall back group read for leader
  perf stat: Print out hint for mixed PMU group error
  perf pmu: Fix core PMU alias list for X86 platform
  perf record: Fix s390 undefined record__auxtrace_init() return value
  perf mem: Document incorrect and missing options
  perf evsel: Disable write_backward for leader sampling group events
  perf pmu: Fix pmu events parsing rule
  perf stat: Keep the / modifier separator in fallback
  perf test: Adapt test case record+probe_libc_inet_pton.sh for s390
  perf list: Remove s390 specific strcmp_cpuid_cmp function
  perf machine: Set main kernel end address properly

Pull ext4 fixes from Ted Ts'o:
 "Fix misc bugs and a regression for ext4"

* tag 'for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: add MODULE_SOFTDEP to ensure crc32c is included in the initramfs
  ext4: fix bitmap position validation
  ext4: set h_journal if there is a failure starting a reserved handle
  ext4: prevent right-shifting extents beyond EXT_MAX_BLOCKS