linux-stable.git/lib/iov_iter.c, branch v5.4.136

iov_iter_fault_in_readable() should do nothing in xarray case

2021-07-14T14:53:01+00:00

commit 0e8f0d67401589a141950856902c7d0ec8d9c985 upstream.

... and actually should just check it's given an iovec-backed iterator
in the first place.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman

copy_page_to_iter(): fix ITER_DISCARD case

2021-07-14T14:53:01+00:00

commit a506abc7b644d71966a75337d5a534f531b3cdc4 upstream.

we need to advance the iterator...

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro 
Signed-off-by: Greg Kroah-Hartman

udp: fix skb_copy_and_csum_datagram with odd segment sizes

2021-02-17T09:35:19+00:00

commit 52cbd23a119c6ebf40a527e53f3402d2ea38eccb upstream.

When iteratively computing a checksum with csum_block_add, track the
offset "pos" to correctly rotate in csum_block_add when offset is odd.

The open coded implementation of skb_copy_and_csum_datagram did this.
With the switch to __skb_datagram_iter calling csum_and_copy_to_iter,
pos was reinitialized to 0 on each call.

Bring back the pos by passing it along with the csum to the callback.

Changes v1->v2
  - pass csum value, instead of csump pointer (Alexander Duyck)

Link: https://lore.kernel.org/netdev/20210128152353.GB27281@optiplex/
Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers")
Reported-by: Oliver Graute 
Signed-off-by: Willem de Bruijn 
Reviewed-by: Alexander Duyck 
Reviewed-by: Eric Dumazet 
Link: https://lore.kernel.org/r/20210203192952.1849843-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

mm: introduce page_size()

2019-09-24T22:54:08+00:00

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

uio: make import_iovec()/compat_import_iovec() return bytes on success

2019-05-31T21:30:03+00:00

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

treewide: Add SPDX license identifier for missed files

2019-05-21T08:50:45+00:00

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 file

These 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

mm/gup: change GUP fast to use flags rather than a write 'bool'

2019-05-14T16:47:46+00:00

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

iov_iter: Fix build error without CONFIG_CRYPTO

2019-04-04T02:37:41+00:00

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

iov_iter: optimize page_copy_sane()

2019-02-26T19:05:20+00:00

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

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2019-01-05T21:18:59+00:00

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