git: 4587326893d2 - stable/14 - uma: Hide 'uma_align_cache'; Create/rename accessors

From: Mark Johnston <markj_at_FreeBSD.org>
Date: Thu, 16 Nov 2023 20:54:39 UTC
The branch stable/14 has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=4587326893d2c7720cd292946d96302a2653b77b

commit 4587326893d2c7720cd292946d96302a2653b77b
Author:     Olivier Certner <olce.freebsd@certner.fr>
AuthorDate: 2023-10-13 09:52:28 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2023-11-16 15:07:07 +0000

    uma: Hide 'uma_align_cache'; Create/rename accessors
    
    Create the uma_get_cache_align_mask() accessor and put it in a separate
    private header so as to minimize namespace pollution in header/source
    files that need only this function and not the whole 'uma.h' header.
    
    Make sure the accessors have '_mask' as a suffix, so that callers are
    aware that the real alignment is the power of two that is the mask plus
    one.  Rename the stem to something more explicit.  Rename
    uma_set_cache_align_mask()'s single parameter to 'mask'.
    
    Hide 'uma_align_cache' to ensure that it cannot be set in any other way
    then by a call to uma_set_cache_align_mask(), which will perform sanity
    checks in a further commit.  While here, rename it to
    'uma_cache_align_mask'.
    
    This is also in preparation for some further changes, such as improving
    the sanity checks, eliminating internal resolving of UMA_ALIGN_CACHE and
    changing the type of the 'uma_cache_align_mask' variable.
    
    Reviewed by:            markj, kib
    MFC after:              2 weeks
    Sponsored by:           The FreeBSD Foundation
    Differential Revision:  https://reviews.freebsd.org/D42258
    
    (cherry picked from commit dc8f7692fd1de628814f4eaf4a233dccf4c92199)
---
 sys/arm/arm/cpufunc.c                              |  2 +-
 .../linuxkpi/common/include/linux/dma-mapping.h    |  4 +--
 sys/vm/uma.h                                       |  6 ++--
 sys/vm/uma_align_mask.h                            | 36 ++++++++++++++++++++++
 sys/vm/uma_core.c                                  | 18 ++++++++---
 5 files changed, 56 insertions(+), 10 deletions(-)

diff --git a/sys/arm/arm/cpufunc.c b/sys/arm/arm/cpufunc.c
index 32b3d2f869c9..f2845eb80f3b 100644
--- a/sys/arm/arm/cpufunc.c
+++ b/sys/arm/arm/cpufunc.c
@@ -254,7 +254,7 @@ set_cpufuncs(void)
 	panic("No support for this CPU type (%08x) in kernel", cputype);
 	return(ARCHITECTURE_NOT_PRESENT);
 out:
-	uma_set_align(arm_dcache_align_mask);
+	uma_set_cache_align_mask(arm_dcache_align_mask);
 	return (0);
 }
 
diff --git a/sys/compat/linuxkpi/common/include/linux/dma-mapping.h b/sys/compat/linuxkpi/common/include/linux/dma-mapping.h
index 330babf761f9..53c59bea8ef2 100644
--- a/sys/compat/linuxkpi/common/include/linux/dma-mapping.h
+++ b/sys/compat/linuxkpi/common/include/linux/dma-mapping.h
@@ -43,6 +43,7 @@
 
 #include <vm/vm.h>
 #include <vm/vm_page.h>
+#include <vm/uma_align_mask.h>
 #include <vm/pmap.h>
 
 #include <machine/bus.h>
@@ -350,8 +351,7 @@ dma_max_mapping_size(struct device *dev)
 #define	dma_unmap_len(p, name)			((p)->name)
 #define	dma_unmap_len_set(p, name, v)		(((p)->name) = (v))
 
-extern int uma_align_cache;
-#define	dma_get_cache_alignment()	uma_align_cache
+#define	dma_get_cache_alignment()	uma_get_cache_align_mask()
 
 
 static inline int
diff --git a/sys/vm/uma.h b/sys/vm/uma.h
index 76f30efc94d1..793f9af3dace 100644
--- a/sys/vm/uma.h
+++ b/sys/vm/uma.h
@@ -470,12 +470,14 @@ void uma_zone_reclaim_domain(uma_zone_t, int req, int domain);
  * alignment.  Should be called by MD boot code prior to starting VM/UMA.
  *
  * Arguments:
- *	align The alignment mask
+ *	mask The alignment mask
  *
  * Returns:
  *	Nothing
  */
-void uma_set_align(int align);
+void uma_set_cache_align_mask(int mask);
+
+#include <vm/uma_align_mask.h>
 
 /*
  * Set a reserved number of items to hold for M_USE_RESERVE allocations.  All
diff --git a/sys/vm/uma_align_mask.h b/sys/vm/uma_align_mask.h
new file mode 100644
index 000000000000..666633350b9d
--- /dev/null
+++ b/sys/vm/uma_align_mask.h
@@ -0,0 +1,36 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2023 The FreeBSD Foundation
+ *
+ * This software was developed by Olivier Certner <olce.freebsd@certner.fr>
+ * at Kumacom SAS under sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _VM_UMA_ALIGN_MASK_H_
+#define _VM_UMA_ALIGN_MASK_H_
+
+int uma_get_cache_align_mask(void) __pure;
+
+#endif /* !_VM_UMA_ALIGN_MASK_H_ */
diff --git a/sys/vm/uma_core.c b/sys/vm/uma_core.c
index de0ab48b0f9b..6e83a27bab27 100644
--- a/sys/vm/uma_core.c
+++ b/sys/vm/uma_core.c
@@ -150,7 +150,7 @@ static uma_zone_t slabzones[2];
 static uma_zone_t hashzone;
 
 /* The boot-time adjusted value for cache line alignment. */
-int uma_align_cache = 64 - 1;
+static int uma_cache_align_mask = 64 - 1;
 
 static MALLOC_DEFINE(M_UMAHASH, "UMAHash", "UMA Hash Buckets");
 static MALLOC_DEFINE(M_UMA, "UMA", "UMA Misc");
@@ -3243,7 +3243,7 @@ uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
 	args.size = size;
 	args.uminit = uminit;
 	args.fini = fini;
-	args.align = (align == UMA_ALIGN_CACHE) ? uma_align_cache : align;
+	args.align = (align == UMA_ALIGN_CACHE) ? uma_cache_align_mask : align;
 	args.flags = flags;
 	args.zone = zone;
 	return (zone_alloc_item(kegs, &args, UMA_ANYDOMAIN, M_WAITOK));
@@ -3252,11 +3252,19 @@ uma_kcreate(uma_zone_t zone, size_t size, uma_init uminit, uma_fini fini,
 /* Public functions */
 /* See uma.h */
 void
-uma_set_align(int align)
+uma_set_cache_align_mask(int mask)
 {
 
-	if (align != UMA_ALIGN_CACHE)
-		uma_align_cache = align;
+	if (mask >= 0)
+		/* UMA_ALIGN_CACHE is also not permitted here. */
+		uma_cache_align_mask = mask;
+}
+
+/* Returns the alignment mask to use to request cache alignment. */
+int
+uma_get_cache_align_mask(void)
+{
+	return (uma_cache_align_mask);
 }
 
 /* See uma.h */