kernel/linux.git/lib/iov_iter.c, branch v5.4.127

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

Remove 'type' argument from access_ok() function

2019-01-04T02:57:57+00:00

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

iov_iter: introduce hash_and_copy_to_iter helper

2018-12-13T08:58:54+00:00

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