memseg.c revision af4c679f647cf088543c762e33d41a3ac52cfa14
/*
*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <sys/types.h>
#include <sys/cmn_err.h>
#include <sys/vm.h>
#include <sys/mman.h>
#include <vm/vm_dep.h>
#include <vm/seg_kmem.h>
#include <vm/seg_kpm.h>
#include <sys/mem_config.h>
#include <sys/sysmacros.h>
extern pgcnt_t pp_dummy_npages;
extern pfn_t *pp_dummy_pfn; /* Array of dummy pfns. */
extern kmutex_t memseg_lists_lock;
extern struct memseg *memseg_va_avail;
extern struct memseg *memseg_alloc();
extern page_t *ppvm_base;
extern pgcnt_t ppvm_size;
static int sun4v_memseg_debug;
extern struct memseg *memseg_reuse(pgcnt_t);
extern void remap_to_dummy(caddr_t, pgcnt_t);
/*
* The page_t memory for incoming pages is allocated from existing memory
* which can create a potential situation where memory addition fails
* because of shortage of existing memory. To mitigate this situation
* some memory is always reserved ahead of time for page_t allocation.
* Each 4MB of reserved page_t's guarantees a 256MB (x64) addition without
* page_t allocation. The added 256MB added memory could theoretically
* allow an addition of 16GB.
*/
#define RSV_SIZE 0x40000000 /* add size with rsrvd page_t's 1G */
#ifdef DEBUG
#define MEMSEG_DEBUG(args...) if (sun4v_memseg_debug) printf(args)
#else
#define MEMSEG_DEBUG(...)
#endif
/*
* The page_t's for the incoming memory are allocated from
* existing pages.
*/
/*ARGSUSED*/
int
memseg_alloc_meta(pfn_t base, pgcnt_t npgs, void **ptp, pgcnt_t *metap)
{
page_t *pp, *opp, *epp;
pgcnt_t metapgs;
int i;
struct seg kseg;
caddr_t vaddr;
/*
* Verify incoming memory is within supported DR range.
*/
if ((base + npgs) * sizeof (page_t) > ppvm_size)
return (KPHYSM_ENOTSUP);
opp = pp = ppvm_base + base;
epp = pp + npgs;
metapgs = btopr(npgs * sizeof (page_t));
if (!IS_P2ALIGNED((uint64_t)pp, PAGESIZE) &&
page_find(&mpvp, (u_offset_t)pp)) {
/*
* Another memseg has page_t's in the same
* page which 'pp' resides. This would happen
* if PAGESIZE is not an integral multiple of
* sizeof (page_t) and therefore 'pp'
* does not start on a page boundry.
*
* Since the other memseg's pages_t's still
* map valid pages, skip allocation of this page.
* Advance 'pp' to the next page which should
* belong only to the incoming memseg.
*
* If the last page_t in the current page
* crosses a page boundary, this should still
* work. The first part of the page_t is
* already allocated. The second part of
* the page_t will be allocated below.
*/
ASSERT(PAGESIZE % sizeof (page_t));
pp = (page_t *)P2ROUNDUP((uint64_t)pp, PAGESIZE);
metapgs--;
}
if (!IS_P2ALIGNED((uint64_t)epp, PAGESIZE) &&
page_find(&mpvp, (u_offset_t)epp)) {
/*
* Another memseg has page_t's in the same
* page which 'epp' resides. This would happen
* if PAGESIZE is not an integral multiple of
* sizeof (page_t) and therefore 'epp'
* does not start on a page boundry.
*
* Since the other memseg's pages_t's still
* map valid pages, skip allocation of this page.
*/
ASSERT(PAGESIZE % sizeof (page_t));
metapgs--;
}
ASSERT(IS_P2ALIGNED((uint64_t)pp, PAGESIZE));
/*
* Back metadata space with physical pages.
*/
kseg.s_as = &kas;
vaddr = (caddr_t)pp;
for (i = 0; i < metapgs; i++)
if (page_find(&mpvp, (u_offset_t)(vaddr + i * PAGESIZE)))
panic("page_find(0x%p, %p)\n",
(void *)&mpvp, (void *)(vaddr + i * PAGESIZE));
/*
* Allocate the metadata pages; these are the pages that will
* contain the page_t's for the incoming memory.
*/
if ((page_create_va(&mpvp, (u_offset_t)pp, ptob(metapgs),
PG_NORELOC | PG_EXCL, &kseg, vaddr)) == NULL) {
MEMSEG_DEBUG("memseg_alloc_meta: can't get 0x%ld metapgs",
metapgs);
return (KPHYSM_ERESOURCE);
}
ASSERT(ptp);
ASSERT(metap);
*ptp = (void *)opp;
*metap = metapgs;
return (KPHYSM_OK);
}
void
memseg_free_meta(void *ptp, pgcnt_t metapgs)
{
int i;
page_t *pp;
u_offset_t off;
if (!metapgs)
return;
off = (u_offset_t)ptp;
ASSERT(off);
ASSERT(IS_P2ALIGNED((uint64_t)off, PAGESIZE));
MEMSEG_DEBUG("memseg_free_meta: off=0x%lx metapgs=0x%lx\n",
(uint64_t)off, metapgs);
/*
* Free pages allocated during add.
*/
for (i = 0; i < metapgs; i++) {
pp = page_find(&mpvp, off);
ASSERT(pp);
ASSERT(pp->p_szc == 0);
page_io_unlock(pp);
page_destroy(pp, 0);
off += PAGESIZE;
}
}
pfn_t
memseg_get_metapfn(void *ptp, pgcnt_t metapg)
{
page_t *pp;
u_offset_t off;
off = (u_offset_t)ptp + ptob(metapg);
ASSERT(off);
ASSERT(IS_P2ALIGNED((uint64_t)off, PAGESIZE));
pp = page_find(&mpvp, off);
ASSERT(pp);
ASSERT(pp->p_szc == 0);
ASSERT(pp->p_pagenum != PFN_INVALID);
return (pp->p_pagenum);
}
/*
* Remap a memseg's page_t's to dummy pages. Skip the low/high
* ends of the range if they are already in use.
*/
void
memseg_remap_meta(struct memseg *seg)
{
int i;
u_offset_t off;
page_t *pp;
#if 0
page_t *epp;
#endif
pgcnt_t metapgs;
metapgs = btopr(MSEG_NPAGES(seg) * sizeof (page_t));
ASSERT(metapgs);
pp = seg->pages;
seg->pages_end = seg->pages_base;
#if 0
epp = seg->epages;
/*
* This code cannot be tested as the kernel does not compile
* when page_t size is changed. It is left here as a starting
* point if the unaligned page_t size needs to be supported.
*/
if (!IS_P2ALIGNED((uint64_t)pp, PAGESIZE) &&
page_find(&mpvp, (u_offset_t)(pp - 1)) && !page_deleted(pp - 1)) {
/*
* Another memseg has page_t's in the same
* page which 'pp' resides. This would happen
* if PAGESIZE is not an integral multiple of
* sizeof (page_t) and therefore 'seg->pages'
* does not start on a page boundry.
*
* Since the other memseg's pages_t's still
* map valid pages, skip remap of this page.
* Advance 'pp' to the next page which should
* belong only to the outgoing memseg.
*
* If the last page_t in the current page
* crosses a page boundary, this should still
* work. The first part of the page_t is
* valid since memseg_lock_delete_all() has
* been called. The second part of the page_t
* will be remapped to the corresponding
* dummy page below.
*/
ASSERT(PAGESIZE % sizeof (page_t));
pp = (page_t *)P2ROUNDUP((uint64_t)pp, PAGESIZE);
metapgs--;
}
if (!IS_P2ALIGNED((uint64_t)epp, PAGESIZE) &&
page_find(&mpvp, (u_offset_t)epp) && !page_deleted(epp)) {
/*
* Another memseg has page_t's in the same
* page which 'epp' resides. This would happen
* if PAGESIZE is not an integral multiple of
* sizeof (page_t) and therefore 'seg->epages'
* does not start on a page boundry.
*
* Since the other memseg's pages_t's still
* map valid pages, skip remap of this page.
*/
ASSERT(PAGESIZE % sizeof (page_t));
metapgs--;
}
#endif
ASSERT(IS_P2ALIGNED((uint64_t)pp, PAGESIZE));
remap_to_dummy((caddr_t)pp, metapgs);
off = (u_offset_t)pp;
MEMSEG_DEBUG("memseg_remap_meta: off=0x%lx metapgs=0x%lx\n",
(uint64_t)off, metapgs);
/*
* Free pages allocated during add.
*/
for (i = 0; i < metapgs; i++) {
pp = page_find(&mpvp, off);
ASSERT(pp);
ASSERT(pp->p_szc == 0);
page_io_unlock(pp);
page_destroy(pp, 0);
off += PAGESIZE;
}
}