platform/kernel/linux-rpi.git
2 years agokasan: support kasan.stacktrace for SW_TAGS
Andrey Konovalov [Mon, 5 Sep 2022 21:05:46 +0000 (23:05 +0200)]
kasan: support kasan.stacktrace for SW_TAGS

Add support for the kasan.stacktrace command-line argument for Software
Tag-Based KASAN.

The following patch adds a command-line argument for selecting the stack
ring size, and, as the stack ring is supported by both the Software and
the Hardware Tag-Based KASAN modes, it is natural that both of them have
support for kasan.stacktrace too.

Link: https://lkml.kernel.org/r/3b43059103faa7f8796017847b7d674b658f11b5.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: implement stack ring for tag-based modes
Andrey Konovalov [Mon, 5 Sep 2022 21:05:45 +0000 (23:05 +0200)]
kasan: implement stack ring for tag-based modes

Implement storing stack depot handles for alloc/free stack traces for slab
objects for the tag-based KASAN modes in a ring buffer.

This ring buffer is referred to as the stack ring.

On each alloc/free of a slab object, the tagged address of the object and
the current stack trace are recorded in the stack ring.

On each bug report, if the accessed address belongs to a slab object, the
stack ring is scanned for matching entries.  The newest entries are used
to print the alloc/free stack traces in the report: one entry for alloc
and one for free.

The number of entries in the stack ring is fixed in this patch, but one of
the following patches adds a command-line argument to control it.

[andreyknvl@google.com: initialize read-write lock in stack ring]
Link: https://lkml.kernel.org/r/576182d194e27531e8090bad809e4136953895f4.1663700262.git.andreyknvl@google.com
Link: https://lkml.kernel.org/r/692de14b6b6a1bc817fd55e4ad92fc1f83c1ab59.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: introduce kasan_complete_mode_report_info
Andrey Konovalov [Mon, 5 Sep 2022 21:05:44 +0000 (23:05 +0200)]
kasan: introduce kasan_complete_mode_report_info

Add bug_type and alloc/free_track fields to kasan_report_info and add a
kasan_complete_mode_report_info() function that fills in these fields.
This function is implemented differently for different KASAN mode.

Change the reporting code to use the filled in fields instead of invoking
kasan_get_bug_type() and kasan_get_alloc/free_track().

For the Generic mode, kasan_complete_mode_report_info() invokes these
functions instead.  For the tag-based modes, only the bug_type field is
filled in; alloc/free_track are handled in the next patch.

Using a single function that fills in these fields is required for the
tag-based modes, as the values for all three fields are determined in a
single procedure implemented in the following patch.

Link: https://lkml.kernel.org/r/8432b861054fa8d0cee79a8877dedeaf3b677ca8.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: rework function arguments in report.c
Andrey Konovalov [Mon, 5 Sep 2022 21:05:43 +0000 (23:05 +0200)]
kasan: rework function arguments in report.c

Pass a pointer to kasan_report_info to describe_object() and
describe_object_stacks(), instead of passing the structure's fields.

The untagged pointer and the tag are still passed as separate arguments to
some of the functions to avoid duplicating the untagging logic.

This is preparatory change for the next patch.

Link: https://lkml.kernel.org/r/2e0cdb91524ab528a3c2b12b6d8bcb69512fc4af.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: fill in cache and object in complete_report_info
Andrey Konovalov [Mon, 5 Sep 2022 21:05:42 +0000 (23:05 +0200)]
kasan: fill in cache and object in complete_report_info

Add cache and object fields to kasan_report_info and fill them in in
complete_report_info() instead of fetching them in the middle of the
report printing code.

This allows the reporting code to get access to the object information
before starting printing the report.  One of the following patches uses
this information to determine the bug type with the tag-based modes.

Link: https://lkml.kernel.org/r/23264572cb2cbb8f0efbb51509b6757eb3cc1fc9.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: introduce complete_report_info
Andrey Konovalov [Mon, 5 Sep 2022 21:05:41 +0000 (23:05 +0200)]
kasan: introduce complete_report_info

Introduce a complete_report_info() function that fills in the
first_bad_addr field of kasan_report_info instead of doing it in
kasan_report_*().

This function will be extended in the next patch.

Link: https://lkml.kernel.org/r/8eb1a9bd01f5d31eab4524da54a101b8720b469e.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: simplify print_report
Andrey Konovalov [Mon, 5 Sep 2022 21:05:40 +0000 (23:05 +0200)]
kasan: simplify print_report

To simplify reading the implementation of print_report(), remove the
tagged_addr variable and rename untagged_addr to addr.

Link: https://lkml.kernel.org/r/f64f5f1093b3c06896bf0f850c5d9e661313fcb2.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: make kasan_addr_to_page static
Andrey Konovalov [Mon, 5 Sep 2022 21:05:39 +0000 (23:05 +0200)]
kasan: make kasan_addr_to_page static

As kasan_addr_to_page() is only used in report.c, rename it to
addr_to_page() and make it static.

Link: https://lkml.kernel.org/r/66c1267200fe0c16e2ac8847a9315fda041918cb.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: use kasan_addr_to_slab in print_address_description
Andrey Konovalov [Mon, 5 Sep 2022 21:05:38 +0000 (23:05 +0200)]
kasan: use kasan_addr_to_slab in print_address_description

Use the kasan_addr_to_slab() helper in print_address_description() instead
of separately invoking PageSlab() and page_slab().

Link: https://lkml.kernel.org/r/8b744fbf8c3c7fc5d34329ec70b60ee5c8dba66c.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: use virt_addr_valid in kasan_addr_to_page/slab
Andrey Konovalov [Mon, 5 Sep 2022 21:05:37 +0000 (23:05 +0200)]
kasan: use virt_addr_valid in kasan_addr_to_page/slab

Instead of open-coding the validity checks for addr in
kasan_addr_to_page/slab(), use the virt_addr_valid() helper.

Link: https://lkml.kernel.org/r/c22a4850d74d7430f8a6c08216fd55c2860a2b9e.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: cosmetic changes in report.c
Andrey Konovalov [Mon, 5 Sep 2022 21:05:36 +0000 (23:05 +0200)]
kasan: cosmetic changes in report.c

Do a few non-functional style fixes for the code in report.c.

Link: https://lkml.kernel.org/r/b728eae71f3ea505a885449724de21cf3f476a7b.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: move kasan_get_alloc/free_track definitions
Andrey Konovalov [Mon, 5 Sep 2022 21:05:35 +0000 (23:05 +0200)]
kasan: move kasan_get_alloc/free_track definitions

Move the definitions of kasan_get_alloc/free_track() to report_*.c, as
they belong with other the reporting code.

Link: https://lkml.kernel.org/r/0cb15423956889b3905a0174b58782633bbbd72e.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: pass tagged pointers to kasan_save_alloc/free_info
Andrey Konovalov [Mon, 5 Sep 2022 21:05:34 +0000 (23:05 +0200)]
kasan: pass tagged pointers to kasan_save_alloc/free_info

Pass tagged pointers to kasan_save_alloc/free_info().

This is a preparatory patch to simplify other changes in the series.

Link: https://lkml.kernel.org/r/d5bc48cfcf0dca8269dc3ed863047e4d4d2030f1.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: only define kasan_cache_create for Generic mode
Andrey Konovalov [Mon, 5 Sep 2022 21:05:33 +0000 (23:05 +0200)]
kasan: only define kasan_cache_create for Generic mode

Right now, kasan_cache_create() assigns SLAB_KASAN for all KASAN modes and
then sets up metadata-related cache parameters for the Generic mode.

SLAB_KASAN is used in two places:

1. In slab_ksize() to account for per-object metadata when
   calculating the size of the accessible memory within the object.
2. In slab_common.c via kasan_never_merge() to prevent merging of
   caches with per-object metadata.

Both cases are only relevant when per-object metadata is present, which is
only the case with the Generic mode.

Thus, assign SLAB_KASAN and define kasan_cache_create() only for the
Generic mode.

Also update the SLAB_KASAN-related comment.

Link: https://lkml.kernel.org/r/61faa2aa1906e2d02c97d00ddf99ce8911dda095.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: only define metadata structs for Generic mode
Andrey Konovalov [Mon, 5 Sep 2022 21:05:32 +0000 (23:05 +0200)]
kasan: only define metadata structs for Generic mode

Hide the definitions of kasan_alloc_meta and kasan_free_meta under an
ifdef CONFIG_KASAN_GENERIC check, as these structures are now only used
when the Generic mode is enabled.

Link: https://lkml.kernel.org/r/8d2aabff8c227c444a3f62edf87d5630beb77640.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: only define metadata offsets for Generic mode
Andrey Konovalov [Mon, 5 Sep 2022 21:05:31 +0000 (23:05 +0200)]
kasan: only define metadata offsets for Generic mode

Hide the definitions of alloc_meta_offset and free_meta_offset under an
ifdef CONFIG_KASAN_GENERIC check, as these fields are now only used when
the Generic mode is enabled.

Link: https://lkml.kernel.org/r/d4bafa0534facafd1a23c465a94261e64f366493.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: only define kasan_never_merge for Generic mode
Andrey Konovalov [Mon, 5 Sep 2022 21:05:30 +0000 (23:05 +0200)]
kasan: only define kasan_never_merge for Generic mode

KASAN prevents merging of slab caches whose objects have per-object
metadata stored in redzones.

As now only the Generic mode uses per-object metadata, define
kasan_never_merge() only for this mode.

Link: https://lkml.kernel.org/r/81ed01f29ff3443580b7e2fe362a8b47b1e8006d.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: only define kasan_metadata_size for Generic mode
Andrey Konovalov [Mon, 5 Sep 2022 21:05:29 +0000 (23:05 +0200)]
kasan: only define kasan_metadata_size for Generic mode

KASAN provides a helper for calculating the size of per-object metadata
stored in the redzone.

As now only the Generic mode uses per-object metadata, only define
kasan_metadata_size() for this mode.

Link: https://lkml.kernel.org/r/8f81d4938b80446bc72538a08217009f328a3e23.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: drop CONFIG_KASAN_GENERIC check from kasan_init_cache_meta
Andrey Konovalov [Mon, 5 Sep 2022 21:05:28 +0000 (23:05 +0200)]
kasan: drop CONFIG_KASAN_GENERIC check from kasan_init_cache_meta

As kasan_init_cache_meta() is only defined for the Generic mode, it does
not require the CONFIG_KASAN_GENERIC check.

Link: https://lkml.kernel.org/r/211f8f2b213aa91e9148ca63342990b491c4917a.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: introduce kasan_init_cache_meta
Andrey Konovalov [Mon, 5 Sep 2022 21:05:27 +0000 (23:05 +0200)]
kasan: introduce kasan_init_cache_meta

Add a kasan_init_cache_meta() helper that initializes metadata-related
cache parameters and use this helper in the common KASAN code.

Put the implementation of this new helper into generic.c, as only the
Generic mode uses per-object metadata.

Link: https://lkml.kernel.org/r/a6d7ea01876eb36472c9879f7b23f1b24766276e.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: introduce kasan_requires_meta
Andrey Konovalov [Mon, 5 Sep 2022 21:05:26 +0000 (23:05 +0200)]
kasan: introduce kasan_requires_meta

Add a kasan_requires_meta() helper that indicates whether the enabled
KASAN mode requires per-object metadata and use this helper in the common
code.

Also hide kasan_init_object_meta() under CONFIG_KASAN_GENERIC ifdef check,
as Generic is the only mode that uses per-object metadata.

To allow for a potential future change that makes Generic KASAN support
the kasan.stacktrace command-line parameter, let kasan_requires_meta()
return kasan_stack_collection_enabled() instead of simply returning true.

Link: https://lkml.kernel.org/r/cf837e9996246aaaeebf704ccf8ec26a34fcf64f.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: move kasan_get_*_meta to generic.c
Andrey Konovalov [Mon, 5 Sep 2022 21:05:25 +0000 (23:05 +0200)]
kasan: move kasan_get_*_meta to generic.c

Move the implementations of kasan_get_alloc/free_meta() to generic.c, as
the common KASAN code does not use these functions anymore.

Also drop kasan_reset_tag() from the implementation, as the Generic mode
does not tag pointers.

Link: https://lkml.kernel.org/r/ffcfc0ad654d78a2ef4ca054c943ddb4e5ca477b.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: clear metadata functions for tag-based modes
Andrey Konovalov [Mon, 5 Sep 2022 21:05:24 +0000 (23:05 +0200)]
kasan: clear metadata functions for tag-based modes

Remove implementations of the metadata-related functions for the tag-based
modes.

The following patches in the series will provide alternative
implementations.

As of this patch, the tag-based modes no longer collect alloc and free
stack traces.  This functionality will be restored later in the series.

Link: https://lkml.kernel.org/r/470fbe5d15e8015092e76e395de354be18ccceab.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: introduce kasan_init_object_meta
Andrey Konovalov [Mon, 5 Sep 2022 21:05:23 +0000 (23:05 +0200)]
kasan: introduce kasan_init_object_meta

Add a kasan_init_object_meta() helper that initializes metadata for a slab
object and use it in the common code.

For now, the implementations of this helper are the same for the Generic
and tag-based modes, but they will diverge later in the series.

This change hides references to alloc_meta from the common code.  This is
desired as only the Generic mode will be using per-object metadata after
this series.

Link: https://lkml.kernel.org/r/47c12938fc7f8105e7aaa592527c0e9d3c81fc37.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: introduce kasan_get_alloc_track
Andrey Konovalov [Mon, 5 Sep 2022 21:05:22 +0000 (23:05 +0200)]
kasan: introduce kasan_get_alloc_track

Add a kasan_get_alloc_track() helper that fetches alloc_track for a slab
object and use this helper in the common reporting code.

For now, the implementations of this helper are the same for the Generic
and tag-based modes, but they will diverge later in the series.

This change hides references to alloc_meta from the common reporting code.
This is desired as only the Generic mode will be using per-object
metadata after this series.

Link: https://lkml.kernel.org/r/0c365a35f4a833fff46f9d42c3212b32f7166556.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: introduce kasan_print_aux_stacks
Andrey Konovalov [Mon, 5 Sep 2022 21:05:21 +0000 (23:05 +0200)]
kasan: introduce kasan_print_aux_stacks

Add a kasan_print_aux_stacks() helper that prints the auxiliary stack
traces for the Generic mode.

This change hides references to alloc_meta from the common reporting code.
This is desired as only the Generic mode will be using per-object
metadata after this series.

Link: https://lkml.kernel.org/r/67c7a9ea6615533762b1f8ccc267cd7f9bafb749.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: drop CONFIG_KASAN_TAGS_IDENTIFY
Andrey Konovalov [Mon, 5 Sep 2022 21:05:20 +0000 (23:05 +0200)]
kasan: drop CONFIG_KASAN_TAGS_IDENTIFY

Drop CONFIG_KASAN_TAGS_IDENTIFY and related code to simplify making
changes to the reporting code.

The dropped functionality will be restored in the following patches in
this series.

Link: https://lkml.kernel.org/r/4c66ba98eb237e9ed9312c19d423bbcf4ecf88f8.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: split save_alloc_info implementations
Andrey Konovalov [Mon, 5 Sep 2022 21:05:19 +0000 (23:05 +0200)]
kasan: split save_alloc_info implementations

Provide standalone implementations of save_alloc_info() for the Generic
and tag-based modes.

For now, the implementations are the same, but they will diverge later in
the series.

Link: https://lkml.kernel.org/r/77f1a078489c1e859aedb5403f772e5e1f7410a0.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: move is_kmalloc check out of save_alloc_info
Andrey Konovalov [Mon, 5 Sep 2022 21:05:18 +0000 (23:05 +0200)]
kasan: move is_kmalloc check out of save_alloc_info

Move kasan_info.is_kmalloc check out of save_alloc_info().

This is a preparatory change that simplifies the following patches in this
series.

Link: https://lkml.kernel.org/r/df89f1915b788f9a10319905af6d0202a3b30c30.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: rename kasan_set_*_info to kasan_save_*_info
Andrey Konovalov [Mon, 5 Sep 2022 21:05:17 +0000 (23:05 +0200)]
kasan: rename kasan_set_*_info to kasan_save_*_info

Rename set_alloc_info() and kasan_set_free_info() to save_alloc_info() and
kasan_save_free_info().  The new names make more sense.

Link: https://lkml.kernel.org/r/9f04777a15cb9d96bf00331da98e021d732fe1c9.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokasan: check KASAN_NO_FREE_META in __kasan_metadata_size
Andrey Konovalov [Mon, 5 Sep 2022 21:05:16 +0000 (23:05 +0200)]
kasan: check KASAN_NO_FREE_META in __kasan_metadata_size

Patch series "kasan: switch tag-based modes to stack ring from per-object
metadata", v3.

This series makes the tag-based KASAN modes use a ring buffer for storing
stack depot handles for alloc/free stack traces for slab objects instead
of per-object metadata.  This ring buffer is referred to as the stack
ring.

On each alloc/free of a slab object, the tagged address of the object and
the current stack trace are recorded in the stack ring.

On each bug report, if the accessed address belongs to a slab object, the
stack ring is scanned for matching entries.  The newest entries are used
to print the alloc/free stack traces in the report: one entry for alloc
and one for free.

The advantages of this approach over storing stack trace handles in
per-object metadata with the tag-based KASAN modes:

- Allows to find relevant stack traces for use-after-free bugs without
  using quarantine for freed memory. (Currently, if the object was
  reallocated multiple times, the report contains the latest alloc/free
  stack traces, not necessarily the ones relevant to the buggy allocation.)
- Allows to better identify and mark use-after-free bugs, effectively
  making the CONFIG_KASAN_TAGS_IDENTIFY functionality always-on.
- Has fixed memory overhead.

The disadvantage:

- If the affected object was allocated/freed long before the bug happened
  and the stack trace events were purged from the stack ring, the report
  will have no stack traces.

Discussion
==========

The proposed implementation of the stack ring uses a single ring buffer
for the whole kernel.  This might lead to contention due to atomic
accesses to the ring buffer index on multicore systems.

At this point, it is unknown whether the performance impact from this
contention would be significant compared to the slowdown introduced by
collecting stack traces due to the planned changes to the latter part, see
the section below.

For now, the proposed implementation is deemed to be good enough, but this
might need to be revisited once the stack collection becomes faster.

A considered alternative is to keep a separate ring buffer for each CPU
and then iterate over all of them when printing a bug report.  This
approach requires somehow figuring out which of the stack rings has the
freshest stack traces for an object if multiple stack rings have them.

Further plans
=============

This series is a part of an effort to make KASAN stack trace collection
suitable for production.  This requires stack trace collection to be fast
and memory-bounded.

The planned steps are:

1. Speed up stack trace collection (potentially, by using SCS;
   patches on-hold until steps #2 and #3 are completed).
2. Keep stack trace handles in the stack ring (this series).
3. Add a memory-bounded mode to stack depot or provide an alternative
   memory-bounded stack storage.
4. Potentially, implement stack trace collection sampling to minimize
   the performance impact.

This patch (of 34):

__kasan_metadata_size() calculates the size of the redzone for objects in
a slab cache.

When accounting for presence of kasan_free_meta in the redzone, this
function only compares free_meta_offset with 0.  But free_meta_offset
could also be equal to KASAN_NO_FREE_META, which indicates that
kasan_free_meta is not present at all.

Add a comparison with KASAN_NO_FREE_META into __kasan_metadata_size().

Link: https://lkml.kernel.org/r/cover.1662411799.git.andreyknvl@google.com
Link: https://lkml.kernel.org/r/c7b316d30d90e5947eb8280f4dc78856a49298cf.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agofilemap: convert filemap_range_has_writeback() to use folios
Vishal Moola (Oracle) [Mon, 5 Sep 2022 21:45:57 +0000 (14:45 -0700)]
filemap: convert filemap_range_has_writeback() to use folios

Removes 3 calls to compound_head().

Link: https://lkml.kernel.org/r/20220905214557.868606-1-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohugetlb_encode.h: fix undefined behaviour (34 << 26)
Matthias Goergens [Mon, 5 Sep 2022 03:19:04 +0000 (11:19 +0800)]
hugetlb_encode.h: fix undefined behaviour (34 << 26)

Left-shifting past the size of your datatype is undefined behaviour in C.
The literal 34 gets the type `int`, and that one is not big enough to be
left shifted by 26 bits.

An `unsigned` is long enough (on any machine that has at least 32 bits for
their ints.)

For uniformity, we mark all the literals as unsigned.  But it's only
really needed for HUGETLB_FLAG_ENCODE_16GB.

Thanks to Randy Dunlap for an initial review and suggestion.

Link: https://lkml.kernel.org/r/20220905031904.150925-1-matthias.goergens@gmail.com
Signed-off-by: Matthias Goergens <matthias.goergens@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/damon/sysfs: simplify the judgement whether kdamonds are busy
Kaixu Xia [Sun, 4 Sep 2022 14:36:06 +0000 (22:36 +0800)]
mm/damon/sysfs: simplify the judgement whether kdamonds are busy

It is unnecessary to get the number of the running kdamond to judge
whether kdamonds are busy.  Here we can use the
damon_sysfs_kdamond_running() helper and return -EBUSY directly when
finding a running kdamond.  Meanwhile, merging with the judgement that a
kdamond has current sysfs command callback request to make the code more
clear.

Link: https://lkml.kernel.org/r/1662302166-13216-1-git-send-email-kaixuxia@tencent.com
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/hugetlb.c: remove unnecessary initialization of local `err'
Li zeming [Mon, 5 Sep 2022 02:09:18 +0000 (10:09 +0800)]
mm/hugetlb.c: remove unnecessary initialization of local `err'

Link: https://lkml.kernel.org/r/20220905020918.3552-1-zeming@nfschina.com
Signed-off-by: Li zeming <zeming@nfschina.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: convert lock_page_or_retry() to folio_lock_or_retry()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:53 +0000 (20:46 +0100)]
mm: convert lock_page_or_retry() to folio_lock_or_retry()

Remove a call to compound_head() in each of the two callers.

Link: https://lkml.kernel.org/r/20220902194653.1739778-58-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agouprobes: use new_folio in __replace_page()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:52 +0000 (20:46 +0100)]
uprobes: use new_folio in __replace_page()

Saves several calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-57-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agormap: remove page_unlock_anon_vma_read()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:51 +0000 (20:46 +0100)]
rmap: remove page_unlock_anon_vma_read()

This was simply an alias for anon_vma_unlock_read() since 2011.

Link: https://lkml.kernel.org/r/20220902194653.1739778-56-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: convert page_get_anon_vma() to folio_get_anon_vma()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:50 +0000 (20:46 +0100)]
mm: convert page_get_anon_vma() to folio_get_anon_vma()

With all callers now passing in a folio, rename the function and convert
all callers.  Removes a couple of calls to compound_head() and a reference
to page->mapping.

Link: https://lkml.kernel.org/r/20220902194653.1739778-55-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohuge_memory: convert unmap_page() to unmap_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:49 +0000 (20:46 +0100)]
huge_memory: convert unmap_page() to unmap_folio()

Remove a folio->page->folio conversion.

Link: https://lkml.kernel.org/r/20220902194653.1739778-54-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohuge_memory: convert split_huge_page_to_list() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:48 +0000 (20:46 +0100)]
huge_memory: convert split_huge_page_to_list() to use a folio

Saves many calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-53-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomigrate: convert unmap_and_move_huge_page() to use folios
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:47 +0000 (20:46 +0100)]
migrate: convert unmap_and_move_huge_page() to use folios

Saves several calls to compound_head() and removes a couple of uses of
page->lru.

Link: https://lkml.kernel.org/r/20220902194653.1739778-52-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomigrate: convert __unmap_and_move() to use folios
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:46 +0000 (20:46 +0100)]
migrate: convert __unmap_and_move() to use folios

Removes a lot of calls to compound_head().  Also remove a VM_BUG_ON that
can never trigger as the PageAnon bit is the bottom bit of page->mapping.

Link: https://lkml.kernel.org/r/20220902194653.1739778-51-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agormap: convert page_move_anon_rmap() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:45 +0000 (20:46 +0100)]
rmap: convert page_move_anon_rmap() to use a folio

Removes one call to compound_head() and a reference to page->mapping.

Link: https://lkml.kernel.org/r/20220902194653.1739778-50-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: remove try_to_free_swap()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:44 +0000 (20:46 +0100)]
mm: remove try_to_free_swap()

All callers have now been converted to folio_free_swap() and we can remove
this wrapper.

Link: https://lkml.kernel.org/r/20220902194653.1739778-49-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomemcg: convert mem_cgroup_swap_full() to take a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:43 +0000 (20:46 +0100)]
memcg: convert mem_cgroup_swap_full() to take a folio

All callers now have a folio, so convert the function to take a folio.
Saves a couple of calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-48-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: convert do_swap_page() to use folio_free_swap()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:42 +0000 (20:46 +0100)]
mm: convert do_swap_page() to use folio_free_swap()

Also convert should_try_to_free_swap() to use a folio.  This removes a few
calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-47-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoksm: use a folio in replace_page()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:41 +0000 (20:46 +0100)]
ksm: use a folio in replace_page()

Replace three calls to compound_head() with one.

Link: https://lkml.kernel.org/r/20220902194653.1739778-46-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agouprobes: use folios more widely in __replace_page()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:40 +0000 (20:46 +0100)]
uprobes: use folios more widely in __replace_page()

Remove a few hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-45-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomadvise: convert madvise_free_pte_range() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:39 +0000 (20:46 +0100)]
madvise: convert madvise_free_pte_range() to use a folio

Saves a lot of calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-44-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agohuge_memory: convert do_huge_pmd_wp_page() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:38 +0000 (20:46 +0100)]
huge_memory: convert do_huge_pmd_wp_page() to use a folio

Removes many calls to compound_head().  Does not remove the assumption
that a folio may not be larger than a PMD.

Link: https://lkml.kernel.org/r/20220902194653.1739778-43-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: convert do_wp_page() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:37 +0000 (20:46 +0100)]
mm: convert do_wp_page() to use a folio

Saves many calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-42-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoswap: convert swap_writepage() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:36 +0000 (20:46 +0100)]
swap: convert swap_writepage() to use a folio

Removes many calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-41-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoswap_state: convert free_swap_cache() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:35 +0000 (20:46 +0100)]
swap_state: convert free_swap_cache() to use a folio

Saves several calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-40-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: remove lookup_swap_cache()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:34 +0000 (20:46 +0100)]
mm: remove lookup_swap_cache()

All callers have now been converted to swap_cache_get_folio(), so we can
remove this wrapper.

Link: https://lkml.kernel.org/r/20220902194653.1739778-39-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: convert do_swap_page() to use swap_cache_get_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:33 +0000 (20:46 +0100)]
mm: convert do_swap_page() to use swap_cache_get_folio()

Saves a folio->page->folio conversion.

Link: https://lkml.kernel.org/r/20220902194653.1739778-38-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoswapfile: convert unuse_pte_range() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:32 +0000 (20:46 +0100)]
swapfile: convert unuse_pte_range() to use a folio

Delay fetching the precise page from the folio until we're in unuse_pte().
Saves many calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-37-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoswapfile: convert __try_to_reclaim_swap() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:31 +0000 (20:46 +0100)]
swapfile: convert __try_to_reclaim_swap() to use a folio

Saves five calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-36-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoswapfile: convert try_to_unuse() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:30 +0000 (20:46 +0100)]
swapfile: convert try_to_unuse() to use a folio

Saves five calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-35-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: remove shmem_getpage()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:29 +0000 (20:46 +0100)]
shmem: remove shmem_getpage()

With all callers removed, remove this wrapper function.  The flags are now
mysteriously called SGP, but I think we can live with that.

Link: https://lkml.kernel.org/r/20220902194653.1739778-34-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agouserfaultfd: convert mcontinue_atomic_pte() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:28 +0000 (20:46 +0100)]
userfaultfd: convert mcontinue_atomic_pte() to use a folio

shmem_getpage() is being replaced by shmem_get_folio() so use a folio
throughout this function.  Saves several calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-33-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agokhugepaged: call shmem_get_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:27 +0000 (20:46 +0100)]
khugepaged: call shmem_get_folio()

shmem_getpage() is being removed, so call its replacement and find the
precise page ourselves.

Link: https://lkml.kernel.org/r/20220902194653.1739778-32-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_get_link() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:26 +0000 (20:46 +0100)]
shmem: convert shmem_get_link() to use a folio

Symlinks will never use a large folio, but using the folio API removes a
lot of unnecessary folio->page->folio conversions.

Link: https://lkml.kernel.org/r/20220902194653.1739778-31-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_symlink() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:25 +0000 (20:46 +0100)]
shmem: convert shmem_symlink() to use a folio

While symlinks will always be < PAGE_SIZE, using the folio APIs gets rid
of unnecessary calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-30-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_fallocate() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:24 +0000 (20:46 +0100)]
shmem: convert shmem_fallocate() to use a folio

Call shmem_get_folio() and use the folio APIs instead of the page APIs.
Saves several calls to compound_head() and removes assumptions about the
size of a large folio.

Link: https://lkml.kernel.org/r/20220902194653.1739778-29-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_file_read_iter() to use shmem_get_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:23 +0000 (20:46 +0100)]
shmem: convert shmem_file_read_iter() to use shmem_get_folio()

Use a folio throughout, saving five calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-28-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_write_begin() to use shmem_get_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:22 +0000 (20:46 +0100)]
shmem: convert shmem_write_begin() to use shmem_get_folio()

Use a folio throughout this function, saving a couple of calls to
compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-27-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_get_partial_folio() to use shmem_get_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:21 +0000 (20:46 +0100)]
shmem: convert shmem_get_partial_folio() to use shmem_get_folio()

Get rid of an unnecessary folio->page->folio conversion.

Link: https://lkml.kernel.org/r/20220902194653.1739778-26-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: add shmem_get_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:20 +0000 (20:46 +0100)]
shmem: add shmem_get_folio()

With no remaining callers of shmem_getpage_gfp(), add shmem_get_folio()
and reimplement shmem_getpage() as a call to shmem_get_folio().

Link: https://lkml.kernel.org/r/20220902194653.1739778-25-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_read_mapping_page_gfp() to use shmem_get_folio_gfp()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:19 +0000 (20:46 +0100)]
shmem: convert shmem_read_mapping_page_gfp() to use shmem_get_folio_gfp()

Saves a couple of calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-24-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_fault() to use shmem_get_folio_gfp()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:18 +0000 (20:46 +0100)]
shmem: convert shmem_fault() to use shmem_get_folio_gfp()

No particular advantage for this function, but necessary to remove
shmem_getpage_gfp().

[hughd@google.com: fix crash]
Link: https://lkml.kernel.org/r/7693a84-bdc2-27b5-2695-d0fe8566571f@google.com
Link: https://lkml.kernel.org/r/20220902194653.1739778-23-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_getpage_gfp() to shmem_get_folio_gfp()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:17 +0000 (20:46 +0100)]
shmem: convert shmem_getpage_gfp() to shmem_get_folio_gfp()

Add a shmem_getpage_gfp() wrapper for compatibility with current users.

Link: https://lkml.kernel.org/r/20220902194653.1739778-22-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: eliminate struct page from shmem_swapin_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:16 +0000 (20:46 +0100)]
shmem: eliminate struct page from shmem_swapin_folio()

Convert shmem_swapin() to return a folio and use swap_cache_get_folio(),
removing all uses of struct page in this function.

Link: https://lkml.kernel.org/r/20220902194653.1739778-21-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoswap: add swap_cache_get_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:15 +0000 (20:46 +0100)]
swap: add swap_cache_get_folio()

Convert lookup_swap_cache() into swap_cache_get_folio() and add a
lookup_swap_cache() wrapper around it.

[akpm@linux-foundation.org: add CONFIG_SWAP=n stub for swap_cache_get_folio()]
Link: https://lkml.kernel.org/r/20220902194653.1739778-20-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_replace_page() to shmem_replace_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:14 +0000 (20:46 +0100)]
shmem: convert shmem_replace_page() to shmem_replace_folio()

The caller has a folio, so convert the calling convention and rename the
function.

Link: https://lkml.kernel.org/r/20220902194653.1739778-19-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_mfill_atomic_pte() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:13 +0000 (20:46 +0100)]
shmem: convert shmem_mfill_atomic_pte() to use a folio

Assert that this is a single-page folio as there are several assumptions
in here that it's exactly PAGE_SIZE bytes large.  Saves several calls to
compound_head() and removes the last caller of shmem_alloc_page().

Link: https://lkml.kernel.org/r/20220902194653.1739778-18-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomemcg: convert mem_cgroup_swapin_charge_page() to mem_cgroup_swapin_charge_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:12 +0000 (20:46 +0100)]
memcg: convert mem_cgroup_swapin_charge_page() to mem_cgroup_swapin_charge_folio()

All callers now have a folio, so pass it in here and remove an unnecessary
call to page_folio().

Link: https://lkml.kernel.org/r/20220902194653.1739778-17-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: convert do_swap_page()'s swapcache variable to a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:11 +0000 (20:46 +0100)]
mm: convert do_swap_page()'s swapcache variable to a folio

The 'swapcache' variable is used to track whether the page is from the
swapcache or not.  It can do this equally well by being the folio of the
page rather than the page itself, and this saves a number of calls to
compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-16-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: convert do_swap_page() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:10 +0000 (20:46 +0100)]
mm: convert do_swap_page() to use a folio

Removes quite a lot of calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-15-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/swap: convert put_swap_page() to put_swap_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:09 +0000 (20:46 +0100)]
mm/swap: convert put_swap_page() to put_swap_folio()

With all callers now using a folio, we can convert this function.

Link: https://lkml.kernel.org/r/20220902194653.1739778-14-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/swap: convert add_to_swap_cache() to take a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:08 +0000 (20:46 +0100)]
mm/swap: convert add_to_swap_cache() to take a folio

With all callers using folios, we can convert add_to_swap_cache() to take
a folio and use it throughout.

Link: https://lkml.kernel.org/r/20220902194653.1739778-13-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/swap: convert __read_swap_cache_async() to use a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:07 +0000 (20:46 +0100)]
mm/swap: convert __read_swap_cache_async() to use a folio

Remove a few hidden (and one visible) calls to compound_head().

Link: https://lkml.kernel.org/r/20220902194653.1739778-12-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/swapfile: convert try_to_free_swap() to folio_free_swap()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:06 +0000 (20:46 +0100)]
mm/swapfile: convert try_to_free_swap() to folio_free_swap()

Add kernel-doc for folio_free_swap() and make it return bool.  Add a
try_to_free_swap() compatibility wrapper.

Link: https://lkml.kernel.org/r/20220902194653.1739778-11-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/swapfile: remove page_swapcount()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:05 +0000 (20:46 +0100)]
mm/swapfile: remove page_swapcount()

By restructuring folio_swapped(), it can use swap_swapcount() instead of
page_swapcount().  It's even a little more efficient.

Link: https://lkml.kernel.org/r/20220902194653.1739778-10-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_replace_page() to use folios throughout
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:04 +0000 (20:46 +0100)]
shmem: convert shmem_replace_page() to use folios throughout

Introduce folio_set_swap_entry() to abstract how both folio->private and
swp_entry_t work.  Use swap_address_space() directly instead of
indirecting through folio_mapping().  Include an assertion that the old
folio is not large as we only allocate a single-page folio to replace it.
Use folio_put_refs() instead of calling folio_put() twice.

Link: https://lkml.kernel.org/r/20220902194653.1739778-9-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_delete_from_page_cache() to take a folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:03 +0000 (20:46 +0100)]
shmem: convert shmem_delete_from_page_cache() to take a folio

Remove the assertion that the page is not Compound as this function now
handles large folios correctly.

Link: https://lkml.kernel.org/r/20220902194653.1739778-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoshmem: convert shmem_writepage() to use a folio throughout
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:02 +0000 (20:46 +0100)]
shmem: convert shmem_writepage() to use a folio throughout

Even though we will split any large folio that comes in, write the code to
handle large folios so as to not leave a trap for whoever tries to handle
large folios in the swap cache.

Link: https://lkml.kernel.org/r/20220902194653.1739778-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: add folio_add_lru_vma()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:01 +0000 (20:46 +0100)]
mm: add folio_add_lru_vma()

Convert lru_cache_add_inactive_or_unevictable() to folio_add_lru_vma()
and add a compatibility wrapper.

Link: https://lkml.kernel.org/r/20220902194653.1739778-6-willy@infradead.org
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: add split_folio()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:46:00 +0000 (20:46 +0100)]
mm: add split_folio()

This wrapper removes a need to use split_huge_page(&folio->page).  Convert
two callers.

Link: https://lkml.kernel.org/r/20220902194653.1739778-5-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: reimplement folio_order() and folio_nr_pages()
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:45:59 +0000 (20:45 +0100)]
mm: reimplement folio_order() and folio_nr_pages()

Instead of calling compound_order() and compound_nr_pages(), use the folio
directly.  Saves 1905 bytes from mm/filemap.o due to folio_test_large()
now being a cheaper check than PageHead().

Link: https://lkml.kernel.org/r/20220902194653.1739778-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: add the first tail page to struct folio
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:45:58 +0000 (20:45 +0100)]
mm: add the first tail page to struct folio

Some of the static checkers get confused by extracting the page from the
folio and referring to fields in the first tail page.  Adding these fields
to struct folio lets us avoid doing that.  It has the risk that people
will refer to those fields without checking that the folio is actually a
large folio, so prefix them with underscores and document the preferred
function to use instead.

Link: https://lkml.kernel.org/r/20220902194653.1739778-3-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm/vmscan: fix a lot of comments
Matthew Wilcox (Oracle) [Fri, 2 Sep 2022 19:45:57 +0000 (20:45 +0100)]
mm/vmscan: fix a lot of comments

Patch series "MM folio changes for 6.1", v2.

My focus this round has been on shmem.  I believe it is now fully
converted to folios.  Of course, shmem interacts with a lot of the swap
cache and other parts of the kernel, so there are patches all over the MM.

This patch series survives a round of xfstests on tmpfs, which is nice,
but hardly an exhaustive test.  Hugh was nice enough to run a round of
tests on it and found a bug which is fixed in this edition.

This patch (of 57):

A lot of comments mention pages when they should say folios.
Fix them up.

[akpm@linux-foundation.org: fixups for mglru additions]
Link: https://lkml.kernel.org/r/20220902194653.1739778-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20220902194653.1739778-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoksm: convert to use common struct mm_slot
Qi Zheng [Wed, 31 Aug 2022 03:19:51 +0000 (11:19 +0800)]
ksm: convert to use common struct mm_slot

Convert to use common struct mm_slot, no functional change.

Link: https://lkml.kernel.org/r/20220831031951.43152-8-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoksm: convert ksm_mm_slot.link to ksm_mm_slot.hash
Qi Zheng [Wed, 31 Aug 2022 03:19:50 +0000 (11:19 +0800)]
ksm: convert ksm_mm_slot.link to ksm_mm_slot.hash

In order to use common struct mm_slot, convert ksm_mm_slot.link to
ksm_mm_slot.hash in advance, no functional change.

Link: https://lkml.kernel.org/r/20220831031951.43152-7-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoksm: convert ksm_mm_slot.mm_list to ksm_mm_slot.mm_node
Qi Zheng [Wed, 31 Aug 2022 03:19:49 +0000 (11:19 +0800)]
ksm: convert ksm_mm_slot.mm_list to ksm_mm_slot.mm_node

In order to use common struct mm_slot, convert ksm_mm_slot.mm_list to
ksm_mm_slot.mm_node in advance, no functional change.

Link: https://lkml.kernel.org/r/20220831031951.43152-6-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoksm: add the ksm prefix to the names of the ksm private structures
Qi Zheng [Wed, 31 Aug 2022 03:19:48 +0000 (11:19 +0800)]
ksm: add the ksm prefix to the names of the ksm private structures

In order to prevent the name of the private structure of ksm from being
the same as the name of the common structure used in subsequent patches,
prefix their names with ksm in advance.

Link: https://lkml.kernel.org/r/20220831031951.43152-5-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoksm: remove redundant declarations in ksm.h
Qi Zheng [Wed, 31 Aug 2022 03:19:47 +0000 (11:19 +0800)]
ksm: remove redundant declarations in ksm.h

Currently, for struct stable_node, no one uses it in both the
include/linux/ksm.h file and the file that contains it.  For struct
mem_cgroup, it's also not used in ksm.h.  So they're all redundant, just
remove them.

Link: https://lkml.kernel.org/r/20220831031951.43152-4-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: thp: convert to use common struct mm_slot
Qi Zheng [Wed, 31 Aug 2022 03:19:46 +0000 (11:19 +0800)]
mm: thp: convert to use common struct mm_slot

Rename private struct mm_slot to struct khugepaged_mm_slot and convert to
use common struct mm_slot with no functional change.

[zhengqi.arch@bytedance.com: fix build error with CONFIG_SHMEM disabled]
Link: https://lkml.kernel.org/r/639fa8d5-8e5b-2333-69dc-40ed46219364@bytedance.com
Link: https://lkml.kernel.org/r/20220831031951.43152-3-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agomm: introduce common struct mm_slot
Qi Zheng [Wed, 31 Aug 2022 03:19:45 +0000 (11:19 +0800)]
mm: introduce common struct mm_slot

Patch series "add common struct mm_slot and use it in THP and KSM", v2.

At present, both THP and KSM module have similar structures mm_slot for
organizing and recording the information required for scanning mm, and
each defines the following exactly the same operation functions:

 - alloc_mm_slot
 - free_mm_slot
 - get_mm_slot
 - insert_to_mm_slots_hash

In order to de-duplicate these codes, this patchset introduces a common
struct mm_slot, and lets THP and KSM to use it.

This patch (of 7):

At present, both THP and KSM module have similar structures mm_slot for
organizing and recording the information required for scanning mm, and
each defines the following exactly the same operation functions:

 - alloc_mm_slot
 - free_mm_slot
 - get_mm_slot
 - insert_to_mm_slots_hash

In order to de-duplicate these codes, this patch introduces a common
struct mm_slot, and subsequent patches will let THP and KSM to use it.

Link: https://lkml.kernel.org/r/20220831031951.43152-1-zhengqi.arch@bytedance.com
Link: https://lkml.kernel.org/r/20220831031951.43152-2-zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2 years agoksm: add profit monitoring documentation
xu xin [Tue, 30 Aug 2022 14:40:03 +0000 (14:40 +0000)]
ksm: add profit monitoring documentation

Add the description of KSM profit and how to determine it separately in
system-wide range and inner a single process.

Link: https://lkml.kernel.org/r/20220830144003.299870-1-xu.xin16@zte.com.cn
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Reviewed-by: Xiaokai Ran <ran.xiaokai@zte.com.cn>
Reviewed-by: Yang Yang <yang.yang29@zte.com.cn>
Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Izik Eidus <izik.eidus@ravellosystems.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>