02 Nov, 2020
3 commits
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This reverts commit 836219141ff7a77e7fab0bd749edd746fd36fef2.
Bug: 171539436
Signed-off-by: Greg Kroah-Hartman
Change-Id: Ia401cbfe62bf5d9e03afab9f9fc6086bd5b34bbf -
This reverts commit d59c65253c7c23abd670be93fbe6e26ce7a018ae.
Bug: 171539436
Signed-off-by: Greg Kroah-Hartman
Change-Id: I0322dc5061506c74efda0d2340b7305e662fabb6 -
This reverts commit 1c9bbee57862efdc506a68ff1a75fa153f886355.
Bug: 171539436
Signed-off-by: Greg Kroah-Hartman
Change-Id: Id9e03fd9bcd64e8d7be30bd0a88ba1d3538da97c
26 Oct, 2020
1 commit
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…nux/kernel/git/mchehab/linux-media") into android-mainline
Steps on the way to 5.10-rc1
Resolves conflicts in:
fs/userfaultfd.cSigned-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ie3fe3c818f1f6565cfd4fa551de72d2b72ef60af
23 Oct, 2020
3 commits
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This reverts commit fb041b598997d63c0f7d7305dfae70046bf66fe1.
Bug: 171539436
Signed-off-by: Greg Kroah-Hartman
Change-Id: I325ae5c3edd6b4cd4213a5c63fec17df842930b7 -
This reverts commit bfdc59701d6d100c99c3b987bcffd1c204e393c8.
Bug: 171539436
Signed-off-by: Greg Kroah-Hartman
Change-Id: Ibf840a8fb38cb7d5888fb1bb1313647edf0b336e -
This reverts commit 89cd35c58bc2e36bfdc23dde67a429b08cf4ae03.
Bug: 171539436
Signed-off-by: Greg Kroah-Hartman
Change-Id: I44ac1575af118ddbc3ee22a70f81cba282f5372a
17 Oct, 2020
1 commit
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To test fault-tolerance of user memory access functions, introduce fault
injection to usercopy functions.If a failure is expected return either -EFAULT or the total amount of
bytes that were not copied.Signed-off-by: Albert van der Linde
Signed-off-by: Andrew Morton
Reviewed-by: Akinobu Mita
Reviewed-by: Alexander Potapenko
Cc: Al Viro
Cc: Andrey Konovalov
Cc: Arnd Bergmann
Cc: Borislav Petkov
Cc: Dmitry Vyukov
Cc: "H. Peter Anvin"
Cc: Ingo Molnar
Cc: Jonathan Corbet
Cc: Marco Elver
Cc: Peter Zijlstra (Intel)
Cc: Thomas Gleixner
Cc: Christoph Hellwig
Link: http://lkml.kernel.org/r/20200831171733.955393-3-alinde@google.com
Signed-off-by: Linus Torvalds
13 Oct, 2020
2 commits
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Pull compat iovec cleanups from Al Viro:
"Christoph's series around import_iovec() and compat variant thereof"* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
security/keys: remove compat_keyctl_instantiate_key_iov
mm: remove compat_process_vm_{readv,writev}
fs: remove compat_sys_vmsplice
fs: remove the compat readv/writev syscalls
fs: remove various compat readv/writev helpers
iov_iter: transparently handle compat iovecs in import_iovec
iov_iter: refactor rw_copy_check_uvector and import_iovec
iov_iter: move rw_copy_check_uvector() into lib/iov_iter.c
compat.h: fix a spelling error in -
Pull copy_and_csum cleanups from Al Viro:
"Saner calling conventions for csum_and_copy_..._user() and friends"[ Removing 800+ lines of code and cleaning stuff up is good - Linus ]
* 'work.csum_and_copy' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ppc: propagate the calling conventions change down to csum_partial_copy_generic()
amd64: switch csum_partial_copy_generic() to new calling conventions
sparc64: propagate the calling convention changes down to __csum_partial_copy_...()
xtensa: propagate the calling conventions change down into csum_partial_copy_generic()
mips: propagate the calling convention change down into __csum_partial_copy_..._user()
mips: __csum_partial_copy_kernel() has no users left
mips: csum_and_copy_{to,from}_user() are never called under KERNEL_DS
sparc32: propagate the calling conventions change down to __csum_partial_copy_sparc_generic()
i386: propagate the calling conventions change down to csum_partial_copy_generic()
sh: propage the calling conventions change down to csum_partial_copy_generic()
m68k: get rid of zeroing destination on error in csum_and_copy_from_user()
arm: propagate the calling convention changes down to csum_partial_copy_from_user()
alpha: propagate the calling convention changes down to csum_partial_copy.c helpers
saner calling conventions for csum_and_copy_..._user()
csum_and_copy_..._user(): pass 0xffffffff instead of 0 as initial sum
csum_partial_copy_nocheck(): drop the last argument
unify generic instances of csum_partial_copy_nocheck()
icmp_push_reply(): reorder adding the checksum up
skb_copy_and_csum_bits(): don't bother with the last argument
06 Oct, 2020
1 commit
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In reaction to a proposal to introduce a memcpy_mcsafe_fast()
implementation Linus points out that memcpy_mcsafe() is poorly named
relative to communicating the scope of the interface. Specifically what
addresses are valid to pass as source, destination, and what faults /
exceptions are handled.Of particular concern is that even though x86 might be able to handle
the semantics of copy_mc_to_user() with its common copy_user_generic()
implementation other archs likely need / want an explicit path for this
case:On Fri, May 1, 2020 at 11:28 AM Linus Torvalds wrote:
>
> On Thu, Apr 30, 2020 at 6:21 PM Dan Williams wrote:
> >
> > However now I see that copy_user_generic() works for the wrong reason.
> > It works because the exception on the source address due to poison
> > looks no different than a write fault on the user address to the
> > caller, it's still just a short copy. So it makes copy_to_user() work
> > for the wrong reason relative to the name.
>
> Right.
>
> And it won't work that way on other architectures. On x86, we have a
> generic function that can take faults on either side, and we use it
> for both cases (and for the "in_user" case too), but that's an
> artifact of the architecture oddity.
>
> In fact, it's probably wrong even on x86 - because it can hide bugs -
> but writing those things is painful enough that everybody prefers
> having just one function.Replace a single top-level memcpy_mcsafe() with either
copy_mc_to_user(), or copy_mc_to_kernel().Introduce an x86 copy_mc_fragile() name as the rename for the
low-level x86 implementation formerly named memcpy_mcsafe(). It is used
as the slow / careful backend that is supplanted by a fast
copy_mc_generic() in a follow-on patch.One side-effect of this reorganization is that separating copy_mc_64.S
to its own file means that perf no longer needs to track dependencies
for its memcpy_64.S benchmarks.[ bp: Massage a bit. ]
Signed-off-by: Dan Williams
Signed-off-by: Borislav Petkov
Reviewed-by: Tony Luck
Acked-by: Michael Ellerman
Cc:
Link: http://lore.kernel.org/r/CAHk-=wjSqtXAqfUJxFtWNwmguFASTgB0dz1dT3V-78Quiezqbg@mail.gmail.com
Link: https://lkml.kernel.org/r/160195561680.2163339.11574962055305783722.stgit@dwillia2-desk3.amr.corp.intel.com
03 Oct, 2020
2 commits
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Use in compat_syscall to import either native or the compat iovecs, and
remove the now superflous compat_import_iovec.This removes the need for special compat logic in most callers, and
the remaining ones can still be simplified by using __import_iovec
with a bool compat parameter.Signed-off-by: Christoph Hellwig
Signed-off-by: Al Viro -
Split rw_copy_check_uvector into two new helpers with more sensible
calling conventions:- iovec_from_user copies a iovec from userspace either into the provided
stack buffer if it fits, or allocates a new buffer for it. Returns
the actually used iovec. It also verifies that iov_len does fit a
signed type, and handles compat iovecs if the compat flag is set.
- __import_iovec consolidates the native and compat versions of
import_iovec. It calls iovec_from_user, then validates each iovec
actually points to user addresses, and ensures the total length
doesn't overflow.This has two major implications:
- the access_process_vm case loses the total lenght checking, which
wasn't required anyway, given that each call receives two iovecs
for the local and remote side of the operation, and it verifies
the total length on the local side already.
- instead of a single loop there now are two loops over the iovecs.
Given that the iovecs are cache hot this doesn't make a major
differenceSigned-off-by: Christoph Hellwig
Signed-off-by: Al Viro
25 Sep, 2020
1 commit
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This lets the compiler inline it into import_iovec() generating
much better code.Signed-off-by: David Laight
Signed-off-by: Christoph Hellwig
Signed-off-by: Al Viro
21 Aug, 2020
3 commits
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All callers of these primitives will
* discard anything we might've copied in case of error
* ignore the csum value in case of error
* always pass 0xffffffff as the initial sum, so the
resulting csum value (in case of success, that is) will never be 0.That suggest the following calling conventions:
* don't pass err_ptr - just return 0 on error.
* don't bother with zeroing destination, etc. in case of error
* don't pass the initial sum - just use 0xffffffff.This commit does the minimal conversion in the instances of csum_and_copy_...();
the changes of actual asm code behind them are done later in the series.
Note that this asm code is often shared with csum_partial_copy_nocheck();
the difference is that csum_partial_copy_nocheck() passes 0 for initial
sum while csum_and_copy_..._user() pass 0xffffffff. Fortunately, we are
free to pass 0xffffffff in all cases and subsequent patches will use that
freedom without any special comments.A part that could be split off: parisc and uml/i386 claimed to have
csum_and_copy_to_user() instances of their own, but those were identical
to the generic one, so we simply drop them. Not sure if it's worth
a separate commit...Signed-off-by: Al Viro
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Preparation for the change of calling conventions; right now all
callers pass 0 as initial sum. Passing 0xffffffff instead yields
the values comparable mod 0xffff and guarantees that 0 will not
be returned on success.Signed-off-by: Al Viro
-
It's always 0. Note that we theoretically could use ~0U as well -
result will be the same modulo 0xffff, _if_ the damn thing did the
right thing for any value of initial sum; later we'll make use of
that when convenient.However, unlike csum_and_copy_..._user(), there are instances that
did not work for arbitrary initial sums; c6x is one such.Signed-off-by: Al Viro
30 Jun, 2020
1 commit
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The header file linux/uio.h includes crypto/hash.h which pulls in
most of the Crypto API. Since linux/uio.h is used throughout the
kernel this means that every tiny bit of change to the Crypto API
causes the entire kernel to get rebuilt.This patch fixes this by moving it into lib/iov_iter.c instead
where it is actually used.This patch also fixes the ifdef to use CRYPTO_HASH instead of just
CRYPTO which does not guarantee the existence of ahash.Unfortunately a number of drivers were relying on linux/uio.h to
provide access to linux/slab.h. This patch adds inclusions of
linux/slab.h as detected by build failures.Also skbuff.h was relying on this to provide a declaration for
ahash_request. This patch adds a forward declaration instead.Signed-off-by: Herbert Xu
Signed-off-by: Al Viro
21 Mar, 2020
1 commit
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This replaces the kasan instrumentation with generic instrumentation,
implicitly adding KCSAN instrumentation support.For KASAN no functional change is intended.
Suggested-by: Arnd Bergmann
Signed-off-by: Marco Elver
Signed-off-by: Paul E. McKenney
Signed-off-by: Ingo Molnar
17 Dec, 2019
1 commit
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We cannot look at 'i->pipe' unless we know the iter is a pipe. Move the
ring_size load to a branch in iov_iter_alignment() where we've already
checked the iter is a pipe to avoid bogus dereference.Reported-by: syzbot+bea68382bae9490e7dd6@syzkaller.appspotmail.com
Fixes: 8cefc107ca54 ("pipe: Use head and tail pointers for the ring, not cursor and length")
Signed-off-by: Jan Kara
Signed-off-by: Al Viro
02 Dec, 2019
1 commit
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Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann:
"As part of the cleanup of some remaining y2038 issues, I came to
fs/compat_ioctl.c, which still has a couple of commands that need
support for time64_t.In completely unrelated work, I spent time on cleaning up parts of
this file in the past, moving things out into drivers instead.After Al Viro reviewed an earlier version of this series and did a lot
more of that cleanup, I decided to try to completely eliminate the
rest of it and move it all into drivers.This series incorporates some of Al's work and many patches of my own,
but in the end stops short of actually removing the last part, which
is the scsi ioctl handlers. I have patches for those as well, but they
need more testing or possibly a rewrite"* tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits)
scsi: sd: enable compat ioctls for sed-opal
pktcdvd: add compat_ioctl handler
compat_ioctl: move SG_GET_REQUEST_TABLE handling
compat_ioctl: ppp: move simple commands into ppp_generic.c
compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t
compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic
compat_ioctl: unify copy-in of ppp filters
tty: handle compat PPP ioctls
compat_ioctl: move SIOCOUTQ out of compat_ioctl.c
compat_ioctl: handle SIOCOUTQNSD
af_unix: add compat_ioctl support
compat_ioctl: reimplement SG_IO handling
compat_ioctl: move WDIOC handling into wdt drivers
fs: compat_ioctl: move FITRIM emulation into file systems
gfs2: add compat_ioctl support
compat_ioctl: remove unused convert_in_user macro
compat_ioctl: remove last RAID handling code
compat_ioctl: remove /dev/raw ioctl translation
compat_ioctl: remove PCI ioctl translation
compat_ioctl: remove joystick ioctl translation
...
16 Nov, 2019
1 commit
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Split pipe->ring_size into two numbers:
(1) pipe->ring_size - indicates the hard size of the pipe ring.
(2) pipe->max_usage - indicates the maximum number of pipe ring slots that
userspace orchestrated events can fill.This allows for a pipe that is both writable by the general kernel
notification facility and by userspace, allowing plenty of ring space for
notifications to be added whilst preventing userspace from being able to
pin too much unswappable kernel space.Signed-off-by: David Howells
31 Oct, 2019
1 commit
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Convert pipes to use head and tail pointers for the buffer ring rather than
pointer and length as the latter requires two atomic ops to update (or a
combined op) whereas the former only requires one.(1) The head pointer is the point at which production occurs and points to
the slot in which the next buffer will be placed. This is equivalent
to pipe->curbuf + pipe->nrbufs.The head pointer belongs to the write-side.
(2) The tail pointer is the point at which consumption occurs. It points
to the next slot to be consumed. This is equivalent to pipe->curbuf.The tail pointer belongs to the read-side.
(3) head and tail are allowed to run to UINT_MAX and wrap naturally. They
are only masked off when the array is being accessed, e.g.:pipe->bufs[head & mask]
This means that it is not necessary to have a dead slot in the ring as
head == tail isn't ambiguous.(4) The ring is empty if "head == tail".
A helper, pipe_empty(), is provided for this.
(5) The occupancy of the ring is "head - tail".
A helper, pipe_occupancy(), is provided for this.
(6) The number of free slots in the ring is "pipe->ring_size - occupancy".
A helper, pipe_space_for_user() is provided to indicate how many slots
userspace may use.(7) The ring is full if "head - tail >= pipe->ring_size".
A helper, pipe_full(), is provided for this.
Signed-off-by: David Howells
23 Oct, 2019
1 commit
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There are two code locations that implement the SG_IO ioctl: the old
sg.c driver, and the generic scsi_ioctl helper that is in turn used by
multiple drivers.To eradicate the old compat_ioctl conversion handler for the SG_IO
command, I implement a readable pair of put_sg_io_hdr() /get_sg_io_hdr()
helper functions that can be used for both compat and native mode,
and then I call this from both drivers.For the iovec handling, there is already a compat_import_iovec() function
that can simply be called in place of import_iovec().To avoid having to pass the compat/native state through multiple
indirections, I mark the SG_IO command itself as compatible in
fs/compat_ioctl.c and use in_compat_syscall() to figure out where
we are called from.As a side-effect of this, the sg.c driver now also accepts the 32-bit
sg_io_hdr format in compat mode using the read/write interface, not
just ioctl. This should improve compatiblity with old 32-bit binaries,
but it would break if any application intentionally passes the 64-bit
data structure in compat mode here.Steffen Maier helped debug an issue in an earlier version of this patch.
Cc: Steffen Maier
Cc: linux-scsi@vger.kernel.org
Cc: Doug Gilbert
Cc: "James E.J. Bottomley"
Cc: "Martin K. Petersen"
Signed-off-by: Arnd Bergmann
25 Sep, 2019
1 commit
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Patch series "Make working with compound pages easier", v2.
These three patches add three helpers and convert the appropriate
places to use them.This patch (of 3):
It's unnecessarily hard to find out the size of a potentially huge page.
Replace 'PAGE_SIZE << compound_order(page)' with page_size(page).Link: http://lkml.kernel.org/r/20190721104612.19120-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle)
Acked-by: Michal Hocko
Reviewed-by: Andrew Morton
Reviewed-by: Ira Weiny
Acked-by: Kirill A. Shutemov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
01 Jun, 2019
1 commit
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Currently these functions return < 0 on error, and 0 for success.
Change that so that we return < 0 on error, but number of bytes
for success.Some callers already treat the return value that way, others need a
slight tweak.Signed-off-by: Jens Axboe
21 May, 2019
1 commit
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Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the fileThese files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:GPL-2.0-only
Signed-off-by: Thomas Gleixner
Signed-off-by: Greg Kroah-Hartman
15 May, 2019
1 commit
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To facilitate additional options to get_user_pages_fast() change the
singular write parameter to be gup_flags.This patch does not change any functionality. New functionality will
follow in subsequent patches.Some of the get_user_pages_fast() call sites were unchanged because they
already passed FOLL_WRITE or 0 for the write parameter.NOTE: It was suggested to change the ordering of the get_user_pages_fast()
arguments to ensure that callers were converted. This breaks the current
GUP call site convention of having the returned pages be the final
parameter. So the suggestion was rejected.Link: http://lkml.kernel.org/r/20190328084422.29911-4-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20190317183438.2057-4-ira.weiny@intel.com
Signed-off-by: Ira Weiny
Reviewed-by: Mike Marshall
Cc: Aneesh Kumar K.V
Cc: Benjamin Herrenschmidt
Cc: Borislav Petkov
Cc: Dan Williams
Cc: "David S. Miller"
Cc: Heiko Carstens
Cc: Ingo Molnar
Cc: James Hogan
Cc: Jason Gunthorpe
Cc: John Hubbard
Cc: "Kirill A. Shutemov"
Cc: Martin Schwidefsky
Cc: Michal Hocko
Cc: Paul Mackerras
Cc: Peter Zijlstra
Cc: Ralf Baechle
Cc: Rich Felker
Cc: Thomas Gleixner
Cc: Yoshinori Sato
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Apr, 2019
1 commit
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If CONFIG_CRYPTO is not set or set to m,
gcc building warn this:lib/iov_iter.o: In function `hash_and_copy_to_iter':
iov_iter.c:(.text+0x9129): undefined reference to `crypto_stats_get'
iov_iter.c:(.text+0x9152): undefined reference to `crypto_stats_ahash_update'Reported-by: Hulk Robot
Fixes: d05f443554b3 ("iov_iter: introduce hash_and_copy_to_iter helper")
Suggested-by: Al Viro
Signed-off-by: YueHaibing
Signed-off-by: Al Viro
27 Feb, 2019
1 commit
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Avoid cache line miss dereferencing struct page if we can.
page_copy_sane() mostly deals with order-0 pages.
Extra cache line miss is visible on TCP recvmsg() calls dealing
with GRO packets (typically 45 page frags are attached to one skb).Bringing the 45 struct pages into cpu cache while copying the data
is not free, since the freeing of the skb (and associated
page frags put_page()) can happen after cache lines have been evicted.Signed-off-by: Eric Dumazet
Cc: Al Viro
Signed-off-by: Al Viro
06 Jan, 2019
1 commit
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Pull trivial vfs updates from Al Viro:
"A few cleanups + Neil's namespace_unlock() optimization"* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
exec: make prepare_bprm_creds static
genheaders: %-s had been there since v6; %-*s - since v7
VFS: use synchronize_rcu_expedited() in namespace_unlock()
iov_iter: reduce code duplication
04 Jan, 2019
1 commit
-
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.Signed-off-by: Linus Torvalds
13 Dec, 2018
2 commits
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Allow consumers that want to use iov iterator helpers and also update
a predefined hash calculation online when copying data. This is useful
when copying incoming network buffers to a local iterator and calculate
a digest on the incoming stream. nvme-tcp host driver that will be
introduced in following patches is the first consumer via
skb_copy_and_hash_datagram_iter.Acked-by: David S. Miller
Signed-off-by: Sagi Grimberg
Signed-off-by: Christoph Hellwig -
The single caller to csum_and_copy_to_iter is skb_copy_and_csum_datagram
and we are trying to unite its logic with skb_copy_datagram_iter by passing
a callback to the copy function that we want to apply. Thus, we need
to make the checksum pointer private to the function.Acked-by: David S. Miller
Signed-off-by: Sagi Grimberg
Signed-off-by: Christoph Hellwig
28 Nov, 2018
1 commit
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The same combination of csum_partial_copy_nocheck() with csum_add_block()
is used in a bunch of places. Add a helper doing just that and use it.Signed-off-by: Al Viro
26 Nov, 2018
1 commit
-
Signed-off-by: Al Viro
24 Oct, 2018
3 commits
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Add a new iterator, ITER_DISCARD, that can only be used in READ mode and
just discards any data copied to it.This is useful in a network filesystem for discarding any unwanted data
sent by a server.Signed-off-by: David Howells
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In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements. This makes it easier to add further
iterator types. Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself. Only the direction is required.Signed-off-by: David Howells
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Use accessor functions to access an iterator's type and direction. This
allows for the possibility of using some other method of determining the
type of iterator than if-chains with bitwise-AND conditions.Signed-off-by: David Howells
16 Jul, 2018
1 commit
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By mistake the ITER_PIPE early-exit / warning from copy_from_iter() was
cargo-culted in _copy_to_iter_mcsafe() rather than a machine-check-safe
version of copy_to_iter_pipe().Implement copy_pipe_to_iter_mcsafe() being careful to return the
indication of short copies due to a CPU exception.Without this regression-fix all splice reads to dax-mode files fail.
Reported-by: Ross Zwisler
Tested-by: Ross Zwisler
Signed-off-by: Dan Williams
Acked-by: Al Viro
Cc: Andrew Morton
Cc: Andy Lutomirski
Cc: Borislav Petkov
Cc: Linus Torvalds
Cc: Peter Zijlstra
Cc: Thomas Gleixner
Cc: Tony Luck
Fixes: 8780356ef630 ("x86/asm/memcpy_mcsafe: Define copy_to_iter_mcsafe()")
Link: http://lkml.kernel.org/r/153108277278.37979.3327916996902264102.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Ingo Molnar