linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Muchun Song <songmuchun@bytedance.com>
To: glider@google.com, elver@google.com, dvyukov@google.com,
	akpm@linux-foundation.org, jannh@google.com, sjpark@amazon.de,
	muchun.song@linux.dev
Cc: kasan-dev@googlegroups.com, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org,
	Muchun Song <songmuchun@bytedance.com>
Subject: [PATCH 6/6] mm: kfence: replace ALIGN_DOWN(x, PAGE_SIZE) with PAGE_ALIGN_DOWN(x)
Date: Tue, 28 Mar 2023 17:58:07 +0800	[thread overview]
Message-ID: <20230328095807.7014-7-songmuchun@bytedance.com> (raw)
In-Reply-To: <20230328095807.7014-1-songmuchun@bytedance.com>

Replace ALIGN_DOWN(x, PAGE_SIZE) with PAGE_ALIGN_DOWN(x) to simplify
the code a bit.

Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
 mm/kfence/core.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/kfence/core.c b/mm/kfence/core.c
index f205b860f460..dbfb79a4d624 100644
--- a/mm/kfence/core.c
+++ b/mm/kfence/core.c
@@ -230,17 +230,17 @@ static bool alloc_covered_contains(u32 alloc_stack_hash)
 
 static inline void kfence_protect(unsigned long addr)
 {
-	kfence_protect_page(ALIGN_DOWN(addr, PAGE_SIZE), true);
+	kfence_protect_page(PAGE_ALIGN_DOWN(addr), true);
 }
 
 static inline void kfence_unprotect(unsigned long addr)
 {
-	kfence_protect_page(ALIGN_DOWN(addr, PAGE_SIZE), false);
+	kfence_protect_page(PAGE_ALIGN_DOWN(addr), false);
 }
 
 static inline unsigned long metadata_to_pageaddr(const struct kfence_metadata *meta)
 {
-	return ALIGN_DOWN(meta->addr, PAGE_SIZE);
+	return PAGE_ALIGN_DOWN(meta->addr);
 }
 
 /*
@@ -308,7 +308,7 @@ static inline bool check_canary_byte(u8 *addr)
 /* __always_inline this to ensure we won't do an indirect call to fn. */
 static __always_inline void for_each_canary(const struct kfence_metadata *meta, bool (*fn)(u8 *))
 {
-	const unsigned long pageaddr = ALIGN_DOWN(meta->addr, PAGE_SIZE);
+	const unsigned long pageaddr = PAGE_ALIGN_DOWN(meta->addr);
 	unsigned long addr;
 
 	/*
@@ -455,7 +455,7 @@ static void kfence_guarded_free(void *addr, struct kfence_metadata *meta, bool z
 	}
 
 	/* Detect racy use-after-free, or incorrect reallocation of this page by KFENCE. */
-	kcsan_begin_scoped_access((void *)ALIGN_DOWN((unsigned long)addr, PAGE_SIZE), PAGE_SIZE,
+	kcsan_begin_scoped_access((void *)PAGE_ALIGN_DOWN((unsigned long)addr), PAGE_SIZE,
 				  KCSAN_ACCESS_SCOPED | KCSAN_ACCESS_WRITE | KCSAN_ACCESS_ASSERT,
 				  &assert_page_exclusive);
 
@@ -464,7 +464,7 @@ static void kfence_guarded_free(void *addr, struct kfence_metadata *meta, bool z
 
 	/* Restore page protection if there was an OOB access. */
 	if (meta->unprotected_page) {
-		memzero_explicit((void *)ALIGN_DOWN(meta->unprotected_page, PAGE_SIZE), PAGE_SIZE);
+		memzero_explicit((void *)PAGE_ALIGN_DOWN(meta->unprotected_page), PAGE_SIZE);
 		kfence_protect(meta->unprotected_page);
 		meta->unprotected_page = 0;
 	}
-- 
2.11.0



  parent reply	other threads:[~2023-03-28  9:59 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-28  9:58 [PATCH 0/6] Simplify kfence code Muchun Song
2023-03-28  9:58 ` [PATCH 1/6] mm: kfence: simplify kfence pool initialization Muchun Song
2023-03-28 11:55   ` Marco Elver
2023-03-28 12:05     ` Marco Elver
2023-03-28 12:53       ` Muchun Song
2023-03-28  9:58 ` [PATCH 2/6] mm: kfence: check kfence pool size at building time Muchun Song
2023-03-28 10:14   ` Marco Elver
2023-03-28 13:03     ` Muchun Song
2023-03-28  9:58 ` [PATCH 3/6] mm: kfence: make kfence_protect_page() void Muchun Song
2023-03-28 10:32   ` Marco Elver
2023-03-28 13:04     ` Muchun Song
2023-03-28  9:58 ` [PATCH 4/6] mm: kfence: remove useless check for CONFIG_KFENCE_NUM_OBJECTS Muchun Song
2023-04-03  8:59   ` Alexander Potapenko
2023-03-28  9:58 ` [PATCH 5/6] mm: kfence: change kfence pool page layout Muchun Song
2023-03-28 12:59   ` Marco Elver
2023-03-28 13:32     ` Muchun Song
2023-03-28 14:12       ` Marco Elver
2023-03-28  9:58 ` Muchun Song [this message]
2023-03-28 11:55   ` [PATCH 6/6] mm: kfence: replace ALIGN_DOWN(x, PAGE_SIZE) with PAGE_ALIGN_DOWN(x) Marco Elver

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20230328095807.7014-7-songmuchun@bytedance.com \
    --to=songmuchun@bytedance.com \
    --cc=akpm@linux-foundation.org \
    --cc=dvyukov@google.com \
    --cc=elver@google.com \
    --cc=glider@google.com \
    --cc=jannh@google.com \
    --cc=kasan-dev@googlegroups.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=muchun.song@linux.dev \
    --cc=sjpark@amazon.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox