freebsd-dev/sys/vm/vm_init.c
Andrew Gallatin edb2994a62 Conditionally move initial vfs bio alloc above 4G
On machines with just the wrong amount of physical memory (enough to
have a lot of bufs, but not enough to use VM_FREELIST_DMA32) it is
possible for 32-bit address limited devices to have little to no
memory left when attaching, due to potentially large vfs bio configs
consuming all memory below 4GB not protected by VM_FREELIST_ISADMA.
This causes the 32-bit devices to allocate from VM_FREELIST_ISADMA,
leaving that freelist emtpy when ISA devices need DMAable memory.

Rather than decrease VM_DMA32_NPAGES_THRESHOLD, use the time honored
technique of putting initially allocated kernel data structs
at the end (or at least not the beginning) of memory.

Since this allocation is done at boot and is wired, is not freed,
so the system is low on 32-bit (and ISA) dma'ble memory forever.
So it is a good candidate to move above 4GB.

While here, remove an unneeded round_page() from kmem_malloc's size
argument as suggested by alc.  The first thing kmem_malloc() does
is a round_page(size), so there is no need to do it before the call.

Reviewed by: alc
Sponsored by: Netflix
2016-10-03 13:23:43 +00:00

281 lines
8.0 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* from: @(#)vm_init.c 8.1 (Berkeley) 6/11/93
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Authors: Avadis Tevanian, Jr., Michael Wayne Young
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
/*
* Initialize the Virtual Memory subsystem.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/proc.h>
#include <sys/rwlock.h>
#include <sys/malloc.h>
#include <sys/sysctl.h>
#include <sys/systm.h>
#include <sys/selinfo.h>
#include <sys/smp.h>
#include <sys/pipe.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/vmem.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_pager.h>
#include <vm/vm_extern.h>
long physmem;
static int exec_map_entries = 16;
SYSCTL_INT(_vm, OID_AUTO, exec_map_entries, CTLFLAG_RDTUN, &exec_map_entries, 0,
"Maximum number of simultaneous execs");
/*
* System initialization
*/
static void vm_mem_init(void *);
SYSINIT(vm_mem, SI_SUB_VM, SI_ORDER_FIRST, vm_mem_init, NULL);
/*
* Import kva into the kernel arena.
*/
static int
kva_import(void *unused, vmem_size_t size, int flags, vmem_addr_t *addrp)
{
vm_offset_t addr;
int result;
addr = vm_map_min(kernel_map);
result = vm_map_find(kernel_map, NULL, 0, &addr, size, 0,
VMFS_SUPER_SPACE, VM_PROT_ALL, VM_PROT_ALL, MAP_NOFAULT);
if (result != KERN_SUCCESS)
return (ENOMEM);
*addrp = addr;
return (0);
}
/*
* vm_init initializes the virtual memory system.
* This is done only by the first cpu up.
*
* The start and end address of physical memory is passed in.
*/
/* ARGSUSED*/
static void
vm_mem_init(dummy)
void *dummy;
{
/*
* Initializes resident memory structures. From here on, all physical
* memory is accounted for, and we use only virtual addresses.
*/
vm_set_page_size();
virtual_avail = vm_page_startup(virtual_avail);
/*
* Initialize other VM packages
*/
vmem_startup();
vm_object_init();
vm_map_startup();
kmem_init(virtual_avail, virtual_end);
/*
* Initialize the kernel_arena. This can grow on demand.
*/
vmem_init(kernel_arena, "kernel arena", 0, 0, PAGE_SIZE, 0, 0);
vmem_set_import(kernel_arena, kva_import, NULL, NULL,
#if VM_NRESERVLEVEL > 0
1 << (VM_LEVEL_0_ORDER + PAGE_SHIFT));
#else
/* On non-superpage architectures want large import sizes. */
PAGE_SIZE * 1024);
#endif
kmem_init_zero_region();
pmap_init();
vm_pager_init();
}
void
vm_ksubmap_init(struct kva_md_info *kmi)
{
vm_offset_t firstaddr;
caddr_t v;
vm_size_t size = 0;
long physmem_est;
vm_offset_t minaddr;
vm_offset_t maxaddr;
/*
* Allocate space for system data structures.
* The first available kernel virtual address is in "v".
* As pages of kernel virtual memory are allocated, "v" is incremented.
* As pages of memory are allocated and cleared,
* "firstaddr" is incremented.
*/
/*
* Make two passes. The first pass calculates how much memory is
* needed and allocates it. The second pass assigns virtual
* addresses to the various data structures.
*/
firstaddr = 0;
again:
v = (caddr_t)firstaddr;
/*
* Discount the physical memory larger than the size of kernel_map
* to avoid eating up all of KVA space.
*/
physmem_est = lmin(physmem, btoc(kernel_map->max_offset -
kernel_map->min_offset));
v = kern_vfs_bio_buffer_alloc(v, physmem_est);
/*
* End of first pass, size has been calculated so allocate memory
*/
if (firstaddr == 0) {
size = (vm_size_t)v;
#ifdef VM_FREELIST_DMA32
/*
* Try to protect 32-bit DMAable memory from the largest
* early alloc of wired mem.
*/
firstaddr = kmem_alloc_attr(kernel_arena, size,
M_ZERO | M_NOWAIT, (vm_paddr_t)1 << 32,
~(vm_paddr_t)0, VM_MEMATTR_DEFAULT);
if (firstaddr == 0)
#endif
firstaddr = kmem_malloc(kernel_arena, size,
M_ZERO | M_WAITOK);
if (firstaddr == 0)
panic("startup: no room for tables");
goto again;
}
/*
* End of second pass, addresses have been assigned
*/
if ((vm_size_t)((char *)v - firstaddr) != size)
panic("startup: table size inconsistency");
/*
* Allocate the clean map to hold all of the paging and I/O virtual
* memory.
*/
size = (long)nbuf * BKVASIZE + (long)nswbuf * MAXPHYS +
(long)bio_transient_maxcnt * MAXPHYS;
kmi->clean_sva = firstaddr = kva_alloc(size);
kmi->clean_eva = firstaddr + size;
/*
* Allocate the buffer arena.
*
* Enable the quantum cache if we have more than 4 cpus. This
* avoids lock contention at the expense of some fragmentation.
*/
size = (long)nbuf * BKVASIZE;
kmi->buffer_sva = firstaddr;
kmi->buffer_eva = kmi->buffer_sva + size;
vmem_init(buffer_arena, "buffer arena", kmi->buffer_sva, size,
PAGE_SIZE, (mp_ncpus > 4) ? BKVASIZE * 8 : 0, 0);
firstaddr += size;
/*
* Now swap kva.
*/
swapbkva = firstaddr;
size = (long)nswbuf * MAXPHYS;
firstaddr += size;
/*
* And optionally transient bio space.
*/
if (bio_transient_maxcnt != 0) {
size = (long)bio_transient_maxcnt * MAXPHYS;
vmem_init(transient_arena, "transient arena",
firstaddr, size, PAGE_SIZE, 0, 0);
firstaddr += size;
}
if (firstaddr != kmi->clean_eva)
panic("Clean map calculation incorrect");
/*
* Allocate the pageable submaps.
*/
exec_map = kmem_suballoc(kernel_map, &minaddr, &maxaddr,
exec_map_entries * round_page(PATH_MAX + ARG_MAX), FALSE);
pipe_map = kmem_suballoc(kernel_map, &minaddr, &maxaddr, maxpipekva,
FALSE);
}