+ mm-csky-introduce-arch_mmap_hint.patch added to mm-unstable branch

+ mm-csky-introduce-arch_mmap_hint.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: csky: introduce arch_mmap_hint()
has been added to the -mm mm-unstable branch.  Its filename is
     mm-csky-introduce-arch_mmap_hint.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-csky-introduce-arch_mmap_hint.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Kalesh Singh <kaleshsingh@google.com>
Subject: mm: csky: introduce arch_mmap_hint()
Date: Wed, 11 Dec 2024 15:27:44 -0800

Introduce csky arch_mmap_hint() and define HAVE_ARCH_MMAP_HINT.  This is a
preparatory patch, no functional change is introduced.

Link: https://lkml.kernel.org/r/20241211232754.1583023-7-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Breno Leitao <leitao@debian.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jason Andryuk <jason.andryuk@amd.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <yang@os.amperecomputing.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/csky/abiv1/inc/abi/pgtable-bits.h |    1 
 arch/csky/abiv1/mmap.c                 |   68 ++++++++++++-----------
 2 files changed, 38 insertions(+), 31 deletions(-)

--- a/arch/csky/abiv1/inc/abi/pgtable-bits.h~mm-csky-introduce-arch_mmap_hint
+++ a/arch/csky/abiv1/inc/abi/pgtable-bits.h
@@ -51,5 +51,6 @@
 					((offset) << 10)})
 
 #define HAVE_ARCH_UNMAPPED_AREA
+#define HAVE_ARCH_MMAP_HINT
 
 #endif /* __ASM_CSKY_PGTABLE_BITS_H */
--- a/arch/csky/abiv1/mmap.c~mm-csky-introduce-arch_mmap_hint
+++ a/arch/csky/abiv1/mmap.c
@@ -13,6 +13,39 @@
 	((((addr)+SHMLBA-1)&~(SHMLBA-1)) +	\
 	 (((pgoff)<<PAGE_SHIFT) & (SHMLBA-1)))
 
+unsigned long arch_mmap_hint(struct file *filp, unsigned long addr,
+			     unsigned long len, unsigned long pgoff,
+			     unsigned long flags)
+{
+	bool do_align;
+
+	if (len > TASK_SIZE)
+		return -ENOMEM;
+
+	/*
+	 * We only need to do colour alignment if either the I or D
+	 * caches alias.
+	 */
+	do_align = filp || (flags & MAP_SHARED);
+
+	/*
+	 * We enforce the MAP_FIXED case.
+	 */
+	if (flags & MAP_FIXED) {
+		if (flags & MAP_SHARED &&
+		    (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
+			return -EINVAL;
+		return addr;
+	}
+
+	if (do_align)
+		addr = COLOUR_ALIGN(addr, pgoff);
+	else
+		addr = PAGE_ALIGN(addr);
+
+	return generic_mmap_hint(filp, addr, len, pgoff, flags);
+}
+
 /*
  * We need to ensure that shared mappings are correctly aligned to
  * avoid aliasing issues with VIPT caches.  We need to ensure that
@@ -27,8 +60,7 @@ arch_get_unmapped_area(struct file *filp
 		unsigned long flags, vm_flags_t vm_flags)
 {
 	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	int do_align = 0;
+	bool do_align;
 	struct vm_unmapped_area_info info = {
 		.length = len,
 		.low_limit = mm->mmap_base,
@@ -36,37 +68,11 @@ arch_get_unmapped_area(struct file *filp
 		.align_offset = pgoff << PAGE_SHIFT
 	};
 
-	/*
-	 * We only need to do colour alignment if either the I or D
-	 * caches alias.
-	 */
-	do_align = filp || (flags & MAP_SHARED);
-
-	/*
-	 * We enforce the MAP_FIXED case.
-	 */
-	if (flags & MAP_FIXED) {
-		if (flags & MAP_SHARED &&
-		    (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
-			return -EINVAL;
+	addr = arch_mmap_hint(filp, addr, len, pgoff, flags);
+	if (addr)
 		return addr;
-	}
-
-	if (len > TASK_SIZE)
-		return -ENOMEM;
-
-	if (addr) {
-		if (do_align)
-			addr = COLOUR_ALIGN(addr, pgoff);
-		else
-			addr = PAGE_ALIGN(addr);
-
-		vma = find_vma(mm, addr);
-		if (TASK_SIZE - len >= addr &&
-		    (!vma || addr + len <= vm_start_gap(vma)))
-			return addr;
-	}
 
+	do_align = filp || (flags & MAP_SHARED);
 	info.align_mask = do_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
 	return vm_unmapped_area(&info);
 }
_

Patches currently in -mm which might be from kaleshsingh@google.com are

mm-introduce-generic_mmap_hint.patch
mm-x86-introduce-arch_mmap_hint.patch
mm-arm-introduce-arch_mmap_hint.patch
mm-alpha-introduce-arch_mmap_hint.patch
mm-arc-use-generic_mmap_hint.patch
mm-csky-introduce-arch_mmap_hint.patch
mm-loongarch-introduce-arch_mmap_hint.patch
mm-mips-introduce-arch_align_mmap_hint.patch
mm-parisc-introduce-arch_align_mmap_hint.patch
mm-s390-use-generic_mmap_hint.patch
mm-sh-introduce-arch_mmap_hint.patch
mm-sparc32-introduce-arch_mmap_hint.patch
mm-sparc64-introduce-arch_mmap_hint.patch
mm-xtensa-introduce-arch_mmap_hint.patch
mm-powerpc-introduce-arch_mmap_hint.patch
mm-respect-mmap-hint-before-thp-alignment-if-allocation-is-possible.patch