uma: Deduplicate uma_small_alloc

This commit refactors the UMA small alloc code and
removes most UMA machine-dependent code.
The existing machine-dependent uma_small_alloc code is almost identical
across all architectures, except for powerpc where using the direct
map addresses involved extra steps in some cases.

The MI/MD split was replaced by a default uma_small_alloc
implementation that can be overridden by architecture-specific code by
defining the UMA_MD_SMALL_ALLOC symbol. Furthermore, UMA_USE_DMAP was
introduced to replace most UMA_MD_SMALL_ALLOC uses.

Reviewed by: markj, kib
Approved by: markj (mentor)
Differential Revision:	https://reviews.freebsd.org/D45084

14 files changed, 57 insertions, 229 deletions

diff --git a/sys/amd64/amd64/uma_machdep.c b/sys/amd64/amd64/uma_machdep.c
deleted file mode 100644
index f83f0674cc4e..000000000000
--- a/sys/amd64/amd64/uma_machdep.c
+++ /dev/null
@@ -1,71 +0,0 @@
-/*-
- * SPDX-License-Identifier: BSD-2-Clause
- *
- * Copyright (c) 2003 Alan L. Cox <alc@cs.rice.edu>
- * All rights reserved.
- *
- * 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.
- */
-
-#include <sys/param.h>
-#include <sys/malloc.h>
-#include <vm/vm.h>
-#include <vm/vm_param.h>
-#include <vm/vm_page.h>
-#include <vm/vm_phys.h>
-#include <vm/vm_dumpset.h>
-#include <vm/uma.h>
-#include <vm/uma_int.h>
-#include <machine/md_var.h>
-
-void *
-uma_small_alloc(uma_zone_t zone, vm_size_t bytes, int domain, u_int8_t *flags,
-    int wait)
-{
-	vm_page_t m;
-	vm_paddr_t pa;
-	void *va;
-
-	*flags = UMA_SLAB_PRIV;
-	m = vm_page_alloc_noobj_domain(domain, malloc2vm_flags(wait) |
-	    VM_ALLOC_WIRED);
-	if (m == NULL)
-		return (NULL);
-	pa = m->phys_addr;
-	if ((wait & M_NODUMP) == 0)
-		dump_add_page(pa);
-	va = (void *)PHYS_TO_DMAP(pa);
-	return (va);
-}
-
-void
-uma_small_free(void *mem, vm_size_t size, u_int8_t flags)
-{
-	vm_page_t m;
-	vm_paddr_t pa;
-
-	pa = DMAP_TO_PHYS((vm_offset_t)mem);
-	dump_drop_page(pa);
-	m = PHYS_TO_VM_PAGE(pa);
-	vm_page_unwire_noq(m);
-	vm_page_free(m);
-}
diff --git a/sys/amd64/include/vmparam.h b/sys/amd64/include/vmparam.h
index bff9bf840036..e5155a7c7d47 100644
--- a/sys/amd64/include/vmparam.h
+++ b/sys/amd64/include/vmparam.h
@@ -72,12 +72,12 @@
 #endif
 
 /*
- * We provide a machine specific single page allocator through the use
- * of the direct mapped segment.  This uses 2MB pages for reduced
+ * We provide a single page allocator through the use of the
+ * direct mapped segment.  This uses 2MB pages for reduced
  * TLB pressure.
  */
 #if !defined(KASAN) && !defined(KMSAN)
-#define	UMA_MD_SMALL_ALLOC
+#define UMA_USE_DMAP
 #endif
 
 /*
diff --git a/sys/arm64/arm64/uma_machdep.c b/sys/arm64/arm64/uma_machdep.c
deleted file mode 100644
index f942248d4dcd..000000000000
--- a/sys/arm64/arm64/uma_machdep.c
+++ /dev/null
@@ -1,69 +0,0 @@
-/*-
- * Copyright (c) 2003 Alan L. Cox <alc@cs.rice.edu>
- * All rights reserved.
- *
- * 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.
- */
-
-#include <sys/param.h>
-#include <sys/malloc.h>
-#include <vm/vm.h>
-#include <vm/vm_param.h>
-#include <vm/vm_page.h>
-#include <vm/vm_phys.h>
-#include <vm/vm_dumpset.h>
-#include <vm/uma.h>
-#include <vm/uma_int.h>
-#include <machine/machdep.h>
-
-void *
-uma_small_alloc(uma_zone_t zone, vm_size_t bytes, int domain, u_int8_t *flags,
-    int wait)
-{
-	vm_page_t m;
-	vm_paddr_t pa;
-	void *va;
-
-	*flags = UMA_SLAB_PRIV;
-	m = vm_page_alloc_noobj_domain(domain, malloc2vm_flags(wait) |
-	    VM_ALLOC_WIRED);
-	if (m == NULL)
-		return (NULL);
-	pa = m->phys_addr;
-	if ((wait & M_NODUMP) == 0)
-		dump_add_page(pa);
-	va = (void *)PHYS_TO_DMAP(pa);
-	return (va);
-}
-
-void
-uma_small_free(void *mem, vm_size_t size, u_int8_t flags)
-{
-	vm_page_t m;
-	vm_paddr_t pa;
-
-	pa = DMAP_TO_PHYS((vm_offset_t)mem);
-	dump_drop_page(pa);
-	m = PHYS_TO_VM_PAGE(pa);
-	vm_page_unwire_noq(m);
-	vm_page_free(m);
-}
diff --git a/sys/arm64/include/vmparam.h b/sys/arm64/include/vmparam.h
index ffa5a538504a..0dcd02d63938 100644
--- a/sys/arm64/include/vmparam.h
+++ b/sys/arm64/include/vmparam.h
@@ -293,7 +293,7 @@
 #endif
 
 #if !defined(KASAN) && !defined(KMSAN)
-#define	UMA_MD_SMALL_ALLOC
+#define UMA_USE_DMAP
 #endif
 
 #ifndef LOCORE
diff --git a/sys/conf/files.amd64 b/sys/conf/files.amd64
index 18dec5ed47b0..add27418ce08 100644
--- a/sys/conf/files.amd64
+++ b/sys/conf/files.amd64
@@ -92,7 +92,6 @@ amd64/amd64/support.S		standard
 amd64/amd64/sys_machdep.c	standard
 amd64/amd64/trap.c		standard
 amd64/amd64/uio_machdep.c	standard
-amd64/amd64/uma_machdep.c	standard
 amd64/amd64/vm_machdep.c	standard
 amd64/pci/pci_cfgreg.c		optional	pci
 cddl/dev/dtrace/amd64/dtrace_asm.S			optional dtrace compile-with "${DTRACE_S}"
diff --git a/sys/conf/files.arm64 b/sys/conf/files.arm64
index a3d4fc09da89..8139a7af8ed3 100644
--- a/sys/conf/files.arm64
+++ b/sys/conf/files.arm64
@@ -78,7 +78,6 @@ arm64/arm64/swtch.S				standard
 arm64/arm64/sys_machdep.c			standard
 arm64/arm64/trap.c				standard
 arm64/arm64/uio_machdep.c			standard
-arm64/arm64/uma_machdep.c			standard
 arm64/arm64/undefined.c				standard
 arm64/arm64/unwind.c				optional ddb | kdtrace_hooks | stack \
 	compile-with "${NORMAL_C:N-fsanitize*:N-fno-sanitize*}"
diff --git a/sys/conf/files.riscv b/sys/conf/files.riscv
index be7ae2b40a08..49c8ddd0c516 100644
--- a/sys/conf/files.riscv
+++ b/sys/conf/files.riscv
@@ -67,7 +67,6 @@ riscv/riscv/sys_machdep.c	standard
 riscv/riscv/trap.c		standard
 riscv/riscv/timer.c		standard
 riscv/riscv/uio_machdep.c	standard
-riscv/riscv/uma_machdep.c	standard
 riscv/riscv/unwind.c		optional	ddb | kdtrace_hooks | stack
 riscv/riscv/vm_machdep.c	standard
 
diff --git a/sys/kern/subr_vmem.c b/sys/kern/subr_vmem.c
index 1c9a8a5be979..a706d944dc3f 100644
--- a/sys/kern/subr_vmem.c
+++ b/sys/kern/subr_vmem.c
@@ -624,14 +624,14 @@ qc_drain(vmem_t *vm)
 		uma_zone_reclaim(vm->vm_qcache[i].qc_cache, UMA_RECLAIM_DRAIN);
 }
 
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 
 static struct mtx_padalign __exclusive_cache_line vmem_bt_lock;
 
 /*
  * vmem_bt_alloc:  Allocate a new page of boundary tags.
  *
- * On architectures with uma_small_alloc there is no recursion; no address
+ * On architectures with UMA_USE_DMAP there is no recursion; no address
  * space need be allocated to allocate boundary tags.  For the others, we
  * must handle recursion.  Boundary tags are necessary to allocate new
  * boundary tags.
@@ -707,7 +707,7 @@ vmem_startup(void)
 	vmem_bt_zone = uma_zcreate("vmem btag",
 	    sizeof(struct vmem_btag), NULL, NULL, NULL, NULL,
 	    UMA_ALIGN_PTR, UMA_ZONE_VM);
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 	mtx_init(&vmem_bt_lock, "btag lock", NULL, MTX_DEF);
 	uma_prealloc(vmem_bt_zone, BT_MAXALLOC);
 	/*
diff --git a/sys/powerpc/include/vmparam.h b/sys/powerpc/include/vmparam.h
index 89982a618bc7..250da8298610 100644
--- a/sys/powerpc/include/vmparam.h
+++ b/sys/powerpc/include/vmparam.h
@@ -111,6 +111,8 @@
 
 #define	KERNBASE		0x00100100	/* start of kernel virtual */
 
+#define UMA_MD_SMALL_ALLOC
+
 #ifdef AIM
 #ifndef __powerpc64__
 #define	VM_MIN_KERNEL_ADDRESS	((vm_offset_t)KERNEL_SR << ADDR_SR_SHFT)
@@ -122,13 +124,13 @@
  * Use the direct-mapped BAT registers for UMA small allocs. This
  * takes pressure off the small amount of available KVA.
  */
-#define UMA_MD_SMALL_ALLOC
+#define UMA_USE_DMAP
 
 #else /* Book-E */
 
 /* Use the direct map for UMA small allocs on powerpc64. */
 #ifdef __powerpc64__
-#define UMA_MD_SMALL_ALLOC
+#define UMA_USE_DMAP
 #else
 #define	VM_MIN_KERNEL_ADDRESS		0xc0000000
 #define	VM_MAX_KERNEL_ADDRESS		0xffffefff
diff --git a/sys/riscv/include/vmparam.h b/sys/riscv/include/vmparam.h
index d2014654b691..5711bc8c347e 100644
--- a/sys/riscv/include/vmparam.h
+++ b/sys/riscv/include/vmparam.h
@@ -234,7 +234,7 @@
 #define	VM_INITIAL_PAGEIN	16
 #endif
 
-#define	UMA_MD_SMALL_ALLOC
+#define UMA_USE_DMAP
 
 #ifndef LOCORE
 extern vm_paddr_t dmap_phys_base;
diff --git a/sys/riscv/riscv/uma_machdep.c b/sys/riscv/riscv/uma_machdep.c
deleted file mode 100644
index 54e0d25800f6..000000000000
--- a/sys/riscv/riscv/uma_machdep.c
+++ /dev/null
@@ -1,68 +0,0 @@
-/*-
- * Copyright (c) 2003 Alan L. Cox <alc@cs.rice.edu>
- * All rights reserved.
- *
- * 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.
- */
-
-#include <sys/param.h>
-#include <sys/malloc.h>
-#include <vm/vm.h>
-#include <vm/vm_param.h>
-#include <vm/vm_page.h>
-#include <vm/vm_phys.h>
-#include <vm/vm_dumpset.h>
-#include <vm/uma.h>
-#include <vm/uma_int.h>
-
-void *
-uma_small_alloc(uma_zone_t zone, vm_size_t bytes, int domain, u_int8_t *flags,
-    int wait)
-{
-	vm_page_t m;
-	vm_paddr_t pa;
-	void *va;
-
-	*flags = UMA_SLAB_PRIV;
-	m = vm_page_alloc_noobj_domain(domain, malloc2vm_flags(wait) |
-	    VM_ALLOC_WIRED);
-	if (m == NULL)
-		return (NULL);
-	pa = m->phys_addr;
-	if ((wait & M_NODUMP) == 0)
-		dump_add_page(pa);
-	va = (void *)PHYS_TO_DMAP(pa);
-	return (va);
-}
-
-void
-uma_small_free(void *mem, vm_size_t size, u_int8_t flags)
-{
-	vm_page_t m;
-	vm_paddr_t pa;
-
-	pa = DMAP_TO_PHYS((vm_offset_t)mem);
-	dump_drop_page(pa);
-	m = PHYS_TO_VM_PAGE(pa);
-	vm_page_unwire_noq(m);
-	vm_page_free(m);
-}
diff --git a/sys/vm/uma_core.c b/sys/vm/uma_core.c
index d185f12448ee..f9b6e18899c6 100644
--- a/sys/vm/uma_core.c
+++ b/sys/vm/uma_core.c
@@ -2079,6 +2079,28 @@ contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
 	    bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
 }
 
+#if defined(UMA_USE_DMAP) && !defined(UMA_MD_SMALL_ALLOC)
+void *
+uma_small_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *flags,
+    int wait)
+{
+	vm_page_t m;
+	vm_paddr_t pa;
+	void *va;
+
+	*flags = UMA_SLAB_PRIV;
+	m = vm_page_alloc_noobj_domain(domain,
+	    malloc2vm_flags(wait) | VM_ALLOC_WIRED);
+	if (m == NULL)
+		return (NULL);
+	pa = m->phys_addr;
+	if ((wait & M_NODUMP) == 0)
+		dump_add_page(pa);
+	va = (void *)PHYS_TO_DMAP(pa);
+	return (va);
+}
+#endif
+
 /*
  * Frees a number of pages to the system
  *
@@ -2141,6 +2163,21 @@ pcpu_page_free(void *mem, vm_size_t size, uint8_t flags)
 	kva_free(sva, size);
 }
 
+#if defined(UMA_USE_DMAP) && !defined(UMA_MD_SMALL_ALLOC)
+void
+uma_small_free(void *mem, vm_size_t size, uint8_t flags)
+{
+	vm_page_t m;
+	vm_paddr_t pa;
+
+	pa = DMAP_TO_PHYS((vm_offset_t)mem);
+	dump_drop_page(pa);
+	m = PHYS_TO_VM_PAGE(pa);
+	vm_page_unwire_noq(m);
+	vm_page_free(m);
+}
+#endif
+
 /*
  * Zero fill initializer
  *
@@ -3154,7 +3191,7 @@ uma_startup1(vm_offset_t virtual_avail)
 	smr_init();
 }
 
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 extern void vm_radix_reserve_kva(void);
 #endif
 
@@ -3174,7 +3211,7 @@ uma_startup2(void)
 		vm_map_unlock(kernel_map);
 	}
 
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 	/* Set up radix zone to use noobj_alloc. */
 	vm_radix_reserve_kva();
 #endif
@@ -5171,7 +5208,7 @@ uma_zone_reserve_kva(uma_zone_t zone, int count)
 
 	pages = howmany(count, keg->uk_ipers) * keg->uk_ppera;
 
-#ifdef UMA_MD_SMALL_ALLOC
+#ifdef UMA_USE_DMAP
 	if (keg->uk_ppera > 1) {
 #else
 	if (1) {
diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c
index 3111dda6e99d..3c7afcb6642f 100644
--- a/sys/vm/vm_map.c
+++ b/sys/vm/vm_map.c
@@ -172,7 +172,7 @@ static void vm_map_wire_entry_failure(vm_map_t map, vm_map_entry_t entry,
 			start = end;			\
 		}
 
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 
 /*
  * Allocate a new slab for kernel map entries.  The kernel map may be locked or
@@ -264,7 +264,7 @@ vm_map_startup(void)
 	kmapentzone = uma_zcreate("KMAP ENTRY", sizeof(struct vm_map_entry),
 	    NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
 	    UMA_ZONE_VM | UMA_ZONE_NOBUCKET);
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 	/* Reserve an extra map entry for use when replenishing the reserve. */
 	uma_zone_reserve(kmapentzone, KMAPENT_RESERVE + 1);
 	uma_prealloc(kmapentzone, KMAPENT_RESERVE + 1);
@@ -660,7 +660,7 @@ _vm_map_unlock(vm_map_t map, const char *file, int line)
 
 	VM_MAP_UNLOCK_CONSISTENT(map);
 	if (map->system_map) {
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 		if (map == kernel_map && (map->flags & MAP_REPLENISH) != 0) {
 			uma_prealloc(kmapentzone, 1);
 			map->flags &= ~MAP_REPLENISH;
@@ -937,7 +937,7 @@ vm_map_entry_create(vm_map_t map)
 {
 	vm_map_entry_t new_entry;
 
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 	if (map == kernel_map) {
 		VM_MAP_ASSERT_LOCKED(map);
 
diff --git a/sys/vm/vm_radix.c b/sys/vm/vm_radix.c
index cfc5a82eacc8..13f9d36194ab 100644
--- a/sys/vm/vm_radix.c
+++ b/sys/vm/vm_radix.c
@@ -82,7 +82,7 @@ vm_radix_node_free(struct pctrie *ptree, void *node)
 	uma_zfree_smr(vm_radix_node_zone, node);
 }
 
-#ifndef UMA_MD_SMALL_ALLOC
+#ifndef UMA_USE_DMAP
 void vm_radix_reserve_kva(void);
 /*
  * Reserve the KVA necessary to satisfy the node allocation.