linux/include
David Hildenbrand aa39ca6940 mm/pagewalk: introduce folio_walk_start() + folio_walk_end()
We want to get rid of follow_page(), and have a more reasonable way to
just lookup a folio mapped at a certain address, perform some checks while
still under PTL, and then only conditionally grab a folio reference if
really required.

Further, we might want to get rid of some walk_page_range*() users that
really only want to temporarily lookup a single folio at a single address.

So let's add a new page table walker that does exactly that, similarly to
GUP also being able to walk hugetlb VMAs.

Add folio_walk_end() as a macro for now: the compiler is not easy to
please with the pte_unmap()->kunmap_local().

Note that one difference between follow_page() and get_user_pages(1) is
that follow_page() will not trigger faults to get something mapped.  So
folio_walk is at least currently not a replacement for get_user_pages(1),
but could likely be extended/reused to achieve something similar in the
future.

Link: https://lkml.kernel.org/r/20240802155524.517137-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Janosch Frank <frankja@linux.ibm.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:25:59 -07:00
..
acpi ACPI: video: Add Dell UART backlight controller detection 2024-08-19 15:58:35 +02:00
asm-generic runtime constants: deal with old decrepit linkers 2024-08-03 08:38:45 -07:00
clocksource
crypto
drm A revert for a previous TTM commit causing stuttering, 3 fixes for 2024-08-30 11:28:11 +10:00
dt-bindings I3C for 6.11 2024-07-27 10:53:06 -07:00
keys
kunit kunit: Introduce KUNIT_ASSERT_MEMEQ and KUNIT_ASSERT_MEMNEQ macros 2024-07-12 10:12:11 -06:00
kvm
linux mm/pagewalk: introduce folio_walk_start() + folio_walk_end() 2024-09-01 20:25:59 -07:00
math-emu
media media: rc: add keymap for MyGica UTV3 remote 2024-06-29 12:20:05 +02:00
memory
misc
net netfilter pull request 24-08-28 2024-08-29 11:35:54 +02:00
pcmcia
ras mm/memory-failure: remove obsolete MF_MSG_DIFFERENT_COMPOUND 2024-07-12 15:52:22 -07:00
rdma RDMA/core: Introduce "name_assign_type" for an IB device 2024-07-04 07:59:53 +03:00
rv
scsi scsi: core: Fix the return value of scsi_logical_block_count() 2024-08-16 21:02:06 -04:00
soc net: mscc: ocelot: treat 802.1ad tagged traffic as 802.1Q-untagged 2024-08-16 09:59:32 +01:00
sound ASoC: Fixes for v6.11 2024-08-09 09:58:07 +02:00
target
trace mm: improve code consistency with zonelist_* helper functions 2024-09-01 20:25:55 -07:00
uapi drm/xe/oa/uapi: Make bit masks unsigned 2024-08-19 10:44:18 -04:00
ufs scsi: ufs: core: Add a quirk for handling broken LSDBS field in controller capabilities register 2024-08-16 21:09:17 -04:00
vdso Random number generator updates for Linux 6.11-rc1. 2024-07-24 10:29:50 -07:00
video
xen Driver core changes for 6.11-rc1 2024-07-25 10:42:22 -07:00