pmem.c revision 02bbca1855f5e27ab1fa25720d377f068144c9df
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (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 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* PMEM - Direct mapping physical memory pages to userland process
*
* Provide functions used for directly (w/o occupying kernel virtual address
* space) allocating and exporting physical memory pages to userland.
*/
#include <sys/types.h>
#include <sys/mutex.h>
#include <sys/sunddi.h>
#include <sys/ddidevmap.h>
#include <sys/vnode.h>
#include <sys/sysmacros.h>
#include <sys/project.h>
#include <vm/seg_dev.h>
#include <sys/pmem.h>
#include <vm/hat_i86.h>
#include <sys/task.h>
#include <sys/sdt.h>
/*
* The routines in this file allocate memory which will be accessed through
* the AGP GART hardware. The GART is programmed with the PFNs for this
* memory, and the only mechanism for removing these entries is by an
* explicit process operation (ioctl/close of the driver, or process exit).
* As such, the pages need to remain locked to ensure that they won't be
* relocated or paged out.
*
* To prevent these locked pages from getting in the way of page
* coalescing, we try to allocate large pages from the system, and carve
* them up to satisfy pmem allocation requests. This will keep the locked
* pages within a constrained area of physical memory, limiting the number
* of large pages that would be pinned by our locked pages. This is, of
* course, another take on the infamous kernel cage, and it has many of the
* downsides of the original cage. It also interferes with system-wide
* resource management decisions, as it maintains its own pool of unused
* pages which can't be easily reclaimed and used during low-memory
* situations.
*
* The right solution is for pmem to register a callback that the VM system
* could call, which would temporarily remove any GART entries for pages
* that were being relocated. This would let us leave the pages unlocked,
* which would remove the need for using large pages, which would simplify
* this code a great deal. Unfortunately, the support for these callbacks
* only exists on some SPARC platforms right now.
*
* Note that this is the *only* reason that large pages are used here. The
* GART can't perform large-page translations, and the code appropriately
* falls back to using small pages if page_create_va_large() fails.
*/
#define HOLD_DHP_LOCK(dhp) if (dhp->dh_flags & DEVMAP_ALLOW_REMAP) \
{ mutex_enter(&dhp->dh_lock); }
#define RELE_DHP_LOCK(dhp) if (dhp->dh_flags & DEVMAP_ALLOW_REMAP) \
{ mutex_exit(&dhp->dh_lock); }
#define FROM_LPG(pp) (pp->p_szc != 0)
#define PFIND(pp) (page_pptonum(pp) & (pmem_pgcnt - 1))
/*
* Structs and static variables used for pmem only.
*/
typedef struct pmem_lpg {
page_t *pl_pp; /* start pp */
ulong_t *pl_bitmap; /* allocation status for each page */
ushort_t pl_pfree; /* this large page might be fully freed */
struct pmem_lpg *pl_next;
struct pmem_lpg *pl_prev;
} pmem_lpg_t;
static size_t pmem_lpgsize; /* the size of one large page */
static pgcnt_t pmem_pgcnt; /* the number of small pages in a large page */
static uint_t pmem_lszc; /* page size code of the large page */
/* The segment to be associated with all the allocated pages. */
static struct seg pmem_seg;
/* Fully occupied large pages allocated for pmem. */
static pmem_lpg_t *pmem_occ_lpgs;
/* Memory pool to store residual small pages from large pages. */
static page_t *pmem_mpool = NULL;
/* Number of small pages reside in pmem_mpool currently. */
static pgcnt_t pmem_nmpages = 0;
/* To protect pmem_nmpages, pmem_mpool and pmem_occ_lpgs. */
kmutex_t pmem_mutex;
static int lpg_isfree(pmem_lpg_t *);
static void pmem_lpg_sub(pmem_lpg_t **, pmem_lpg_t *);
static void pmem_lpg_concat(pmem_lpg_t **, pmem_lpg_t **);
static pmem_lpg_t *pmem_lpg_get(pmem_lpg_t *, page_t *, pmem_lpg_t **);
static pmem_lpg_t *pmem_lpg_alloc(uint_t);
static void pmem_lpg_free(pmem_lpg_t **, pmem_lpg_t *);
static void lpg_free(page_t *spp);
static pgcnt_t mpool_break(page_t **, pgcnt_t);
static void mpool_append(page_t **, pgcnt_t);
static void lpp_break(page_t **, pgcnt_t, pgcnt_t, pmem_lpg_t *);
static void lpp_free(page_t *, pgcnt_t, pmem_lpg_t **);
static int lpp_create(page_t **, pgcnt_t, pgcnt_t *, pmem_lpg_t **,
vnode_t *, u_offset_t *, uint_t);
static void tlist_in(page_t *, pgcnt_t, vnode_t *, u_offset_t *);
static void tlist_out(page_t *, pgcnt_t);
static int pmem_cookie_alloc(struct devmap_pmem_cookie **, pgcnt_t, uint_t);
static int pmem_lock(pgcnt_t, kproject_t **);
/*
* Called by driver devmap routine to pass physical memory mapping info to
* seg_dev framework, used only for physical memory allocated from
* devmap_pmem_alloc().
*/
/* ARGSUSED */
int
devmap_pmem_setup(devmap_cookie_t dhc, dev_info_t *dip,
struct devmap_callback_ctl *callbackops, devmap_pmem_cookie_t cookie,
offset_t off, size_t len, uint_t maxprot, uint_t flags,
ddi_device_acc_attr_t *accattrp)
{
devmap_handle_t *dhp = (devmap_handle_t *)dhc;
struct devmap_pmem_cookie *pcp = (struct devmap_pmem_cookie *)cookie;
if (pcp == NULL || (off + len) > ptob(pcp->dp_npages))
return (DDI_FAILURE);
/*
* First to check if this function has been called for this dhp.
*/
if (dhp->dh_flags & DEVMAP_SETUP_DONE)
return (DDI_FAILURE);
if ((dhp->dh_prot & dhp->dh_orig_maxprot & maxprot) != dhp->dh_prot)
return (DDI_FAILURE);
if (flags & DEVMAP_MAPPING_INVALID) {
/*
* If DEVMAP_MAPPING_INVALID is specified, we have to grant
* remap permission.
*/
if (!(flags & DEVMAP_ALLOW_REMAP))
return (DDI_FAILURE);
} else {
dhp->dh_pcookie = (devmap_pmem_cookie_t)pcp;
/* dh_roff is the offset inside the dh_pcookie. */
dhp->dh_roff = ptob(btop(off));
}
/*
* Only "No Cache" and "Write Combining" are supported. If any other
* cache type is specified, override with "No Cache".
*/
if (accattrp->devacc_attr_dataorder == DDI_MERGING_OK_ACC)
dhp->dh_hat_attr = HAT_PLAT_NOCACHE | HAT_MERGING_OK;
else
dhp->dh_hat_attr = HAT_PLAT_NOCACHE | HAT_STRICTORDER;
dhp->dh_cookie = DEVMAP_PMEM_COOKIE;
dhp->dh_flags |= (flags & DEVMAP_SETUP_FLAGS);
dhp->dh_len = ptob(btopr(len));
dhp->dh_maxprot = maxprot & dhp->dh_orig_maxprot;
ASSERT((dhp->dh_prot & dhp->dh_orig_maxprot & maxprot) == dhp->dh_prot);
if (callbackops != NULL) {
bcopy(callbackops, &dhp->dh_callbackops,
sizeof (struct devmap_callback_ctl));
}
/*
* Initialize dh_lock if we want to do remap.
*/
if (dhp->dh_flags & DEVMAP_ALLOW_REMAP) {
mutex_init(&dhp->dh_lock, NULL, MUTEX_DEFAULT, NULL);
dhp->dh_flags |= DEVMAP_LOCK_INITED;
}
dhp->dh_flags |= DEVMAP_SETUP_DONE;
return (DDI_SUCCESS);
}
/*
* Replace existing mapping using a new cookie, mainly gets called when doing
* fork(). Should be called in associated devmap_dup(9E).
*/
/* ARGSUSED */
int
devmap_pmem_remap(devmap_cookie_t dhc, dev_info_t *dip,
devmap_pmem_cookie_t cookie, offset_t off, size_t len, uint_t maxprot,
uint_t flags, ddi_device_acc_attr_t *accattrp)
{
devmap_handle_t *dhp = (devmap_handle_t *)dhc;
struct devmap_pmem_cookie *pcp = (struct devmap_pmem_cookie *)cookie;
/*
* Reture failure if setup has not been done or no remap permission
* has been granted during the setup.
*/
if ((dhp->dh_flags & DEVMAP_SETUP_DONE) == 0 ||
(dhp->dh_flags & DEVMAP_ALLOW_REMAP) == 0)
return (DDI_FAILURE);
/* No flags supported for remap yet. */
if (flags != 0)
return (DDI_FAILURE);
if ((dhp->dh_prot & dhp->dh_orig_maxprot & maxprot) != dhp->dh_prot)
return (DDI_FAILURE);
if (pcp == NULL || (off + len) > ptob(pcp->dp_npages))
return (DDI_FAILURE);
HOLD_DHP_LOCK(dhp);
/*
* Unload the old mapping of pages reloated with this dhp, so next
* fault will setup the new mappings. It is in segdev_faultpage that
* calls hat_devload to establish the mapping. Do this while holding
* the dhp lock so other faults dont reestablish the mappings.
*/
hat_unload(dhp->dh_seg->s_as->a_hat, dhp->dh_uvaddr,
dhp->dh_len, HAT_UNLOAD|HAT_UNLOAD_OTHER);
/*
* Only "No Cache" and "Write Combining" are supported, if other cache
* type is specified, override with "No Cache".
*/
if (accattrp->devacc_attr_dataorder == DDI_MERGING_OK_ACC)
dhp->dh_hat_attr = HAT_MERGING_OK;
else
dhp->dh_hat_attr = HAT_STRICTORDER;
dhp->dh_pcookie = cookie;
dhp->dh_roff = ptob(btop(off));
dhp->dh_len = ptob(btopr(len));
/* Clear the large page size flag. */
dhp->dh_flags &= ~DEVMAP_FLAG_LARGE;
dhp->dh_maxprot = maxprot & dhp->dh_orig_maxprot;
ASSERT((dhp->dh_prot & dhp->dh_orig_maxprot & maxprot) == dhp->dh_prot);
RELE_DHP_LOCK(dhp);
return (DDI_SUCCESS);
}
/*
* Directly (i.e., without occupying kernel virtual address space) allocate
* 'npages' physical memory pages for exporting to user land. The allocated
* page_t pointer will be recorded in cookie.
*/
int
devmap_pmem_alloc(size_t size, uint_t flags, devmap_pmem_cookie_t *cookiep)
{
u_offset_t pmem_off = 0;
page_t *pp = NULL;
page_t *lpp = NULL;
page_t *tlist = NULL;
pgcnt_t i = 0;
pgcnt_t rpages = 0;
pgcnt_t lpages = 0;
pgcnt_t tpages = 0;
pgcnt_t npages = btopr(size);
pmem_lpg_t *plp = NULL;
struct devmap_pmem_cookie *pcp;
uint_t reserved = 0;
uint_t locked = 0;
uint_t pflags, kflags;
*cookiep = NULL;
/*
* Number larger than this will cause page_create_va() to loop
* infinitely.
*/
if (npages == 0 || npages >= total_pages / 2)
return (DDI_FAILURE);
if ((flags & (PMEM_SLEEP | PMEM_NOSLEEP)) == 0)
return (DDI_FAILURE);
pflags = flags & PMEM_NOSLEEP ? PG_EXCL : PG_WAIT;
kflags = flags & PMEM_NOSLEEP ? KM_NOSLEEP : KM_SLEEP;
/* Allocate pmem cookie. */
if (pmem_cookie_alloc(&pcp, npages, kflags) == DDI_FAILURE)
return (DDI_FAILURE);
pcp->dp_npages = npages;
/*
* See if the requested memory can be locked. Currently we do resource
* controls on the project levlel only.
*/
if (pmem_lock(npages, &(pcp->dp_projp)) == DDI_FAILURE)
goto alloc_fail;
locked = 1;
/*
* First, grab as many as possible from pmem_mpool. If pages in
* pmem_mpool are enough for this request, we are done.
*/
mutex_enter(&pmem_mutex);
tpages = mpool_break(&tlist, npages);
/* IOlock and hashin them into the new offset. */
if (tpages)
tlist_in(tlist, tpages, pcp->dp_vnp, &pmem_off);
mutex_exit(&pmem_mutex);
if (tpages == npages)
goto done;
rpages = npages - tpages;
/* Quit now if memory cannot be reserved. */
if (!page_resv(rpages, kflags))
goto alloc_fail;
reserved = 1;
/* Try to allocate large pages first to decrease fragmentation. */
i = (rpages + (pmem_pgcnt - 1)) / pmem_pgcnt;
if (lpp_create(&lpp, i, &lpages, &plp, pcp->dp_vnp, &pmem_off,
kflags) == DDI_FAILURE)
goto alloc_fail;
ASSERT(lpages == 0 ? lpp == NULL : 1);
/*
* Pages in large pages is more than the request, put the residual
* pages into pmem_mpool.
*/
if (lpages >= rpages) {
lpp_break(&lpp, lpages, lpages - rpages, plp);
goto done;
}
/* Allocate small pages if lpp+tlist cannot satisfy the request. */
i = rpages - lpages;
if ((pp = page_create_va(pcp->dp_vnp, pmem_off, ptob(i),
pflags, &pmem_seg, (caddr_t)(uintptr_t)pmem_off)) == NULL)
goto alloc_fail;
done:
page_list_concat(&tlist, &lpp);
page_list_concat(&tlist, &pp);
/* Set those small pages from large pages as allocated. */
mutex_enter(&pmem_mutex);
pmem_lpg_concat(&pmem_occ_lpgs, &plp);
mutex_exit(&pmem_mutex);
/*
* Now tlist holds all the pages for this cookie. Record these pages in
* pmem cookie.
*/
for (pp = tlist, i = 0; i < npages; i++) {
pcp->dp_pparray[i] = pp;
page_io_unlock(pp);
pp = pp->p_next;
page_sub(&tlist, pp->p_prev);
}
ASSERT(tlist == NULL);
*cookiep = (devmap_pmem_cookie_t)pcp;
return (DDI_SUCCESS);
alloc_fail:
DTRACE_PROBE(pmem__alloc__fail);
/* Free large pages and the associated allocation records. */
if (lpp)
lpp_free(lpp, lpages / pmem_pgcnt, &plp);
if (reserved == 1)
page_unresv(rpages);
/* Put those pages in tlist back into pmem_mpool. */
if (tpages != 0) {
mutex_enter(&pmem_mutex);
/* IOunlock, hashout and update the allocation records. */
tlist_out(tlist, tpages);
mpool_append(&tlist, tpages);
mutex_exit(&pmem_mutex);
}
if (locked == 1)
i_ddi_decr_locked_memory(NULL, NULL, pcp->dp_projp, NULL,
ptob(pcp->dp_npages));
/* Freeing pmem_cookie. */
kmem_free(pcp->dp_vnp, sizeof (vnode_t));
kmem_free(pcp->dp_pparray, npages * sizeof (page_t *));
kmem_free(pcp, sizeof (struct devmap_pmem_cookie));
return (DDI_FAILURE);
}
/*
* Free all small pages inside cookie, and return pages from large pages into
* mpool, if all the pages from one large page is in mpool, free it as a whole.
*/
void
devmap_pmem_free(devmap_pmem_cookie_t cookie)
{
struct devmap_pmem_cookie *pcp = (struct devmap_pmem_cookie *)cookie;
pgcnt_t i;
pgcnt_t tpages = 0;
page_t *pp;
pmem_lpg_t *pl1, *plp;
pmem_lpg_t *pf_lpgs = NULL;
uint_t npls = 0;
pmem_lpg_t *last_pl = NULL;
pmem_lpg_t *plast_pl = NULL;
ASSERT(pcp);
mutex_enter(&pmem_mutex);
/* Free small pages and return them to memory pool. */
for (i = pcp->dp_npages; i > 0; i--) {
pp = pcp->dp_pparray[i - 1];
page_hashout(pp, NULL);
/*
* Remove the mapping of this single page, this mapping is
* created using hat_devload() in segdev_faultpage().
*/
(void) hat_pageunload(pp, HAT_FORCE_PGUNLOAD);
if (!FROM_LPG(pp)) {
/* Normal small page. */
page_free(pp, 1);
page_unresv(1);
} else {
/* Small page from large pages. */
plp = pmem_lpg_get(pmem_occ_lpgs, pp, &last_pl);
if (plp && !(plp->pl_pfree)) {
/*
* Move this record to pf_lpgs list, this large
* page may be able to be freed as a whole.
*/
pmem_lpg_sub(&pmem_occ_lpgs, plp);
pmem_lpg_concat(&pf_lpgs, &plp);
plp->pl_pfree = 1;
npls++;
last_pl = NULL;
} else {
/* Search in pf_lpgs list. */
plp = pmem_lpg_get(pf_lpgs, pp, &plast_pl);
}
ASSERT(plp);
/* Mark this page as free. */
BT_SET(plp->pl_bitmap, PFIND(pp));
/* Record this page in pmem_mpool. */
mpool_append(&pp, 1);
}
}
/*
* Find out the large pages whose pages have been freed, remove them
* from plp list, free them and the associated pmem_lpg struct.
*/
for (plp = pf_lpgs; npls != 0; npls--) {
pl1 = plp;
plp = plp->pl_next;
if (lpg_isfree(pl1)) {
/*
* Get one free large page. Find all pages in this
* large page and remove them from pmem_mpool.
*/
lpg_free(pl1->pl_pp);
/* Remove associated allocation records. */
pmem_lpg_sub(&pf_lpgs, pl1);
pmem_lpg_free(&pf_lpgs, pl1);
tpages -= pmem_pgcnt;
} else
pl1->pl_pfree = 0;
}
/* Update allocation records accordingly. */
pmem_lpg_concat(&pmem_occ_lpgs, &pf_lpgs);
mutex_exit(&pmem_mutex);
i_ddi_decr_locked_memory(NULL, NULL, (kproject_t *)pcp->dp_projp, NULL,
ptob(pcp->dp_npages));
kmem_free(pcp->dp_vnp, sizeof (vnode_t));
kmem_free(pcp->dp_pparray, pcp->dp_npages * sizeof (page_t *));
kmem_free(pcp, sizeof (struct devmap_pmem_cookie));
}
/*
* To extract page frame number from specified range in a cookie.
*/
int
devmap_pmem_getpfns(devmap_pmem_cookie_t cookie, uint_t start, pgcnt_t npages,
pfn_t *pfnarray)
{
struct devmap_pmem_cookie *pcp = (struct devmap_pmem_cookie *)cookie;
pgcnt_t i;
if (pcp == NULL || start + npages > pcp->dp_npages)
return (DDI_FAILURE);
for (i = start; i < start + npages; i++)
pfnarray[i - start] = pcp->dp_pparray[i]->p_pagenum;
return (DDI_SUCCESS);
}
void
pmem_init()
{
mutex_init(&pmem_mutex, NULL, MUTEX_DEFAULT, NULL);
pmem_lszc = MIN(1, page_num_pagesizes() - 1);
pmem_lpgsize = page_get_pagesize(pmem_lszc);
pmem_pgcnt = pmem_lpgsize >> PAGESHIFT;
bzero(&pmem_seg, sizeof (struct seg));
pmem_seg.s_as = &kas;
}
/* Allocate kernel memory for one pmem cookie with n pages. */
static int
pmem_cookie_alloc(struct devmap_pmem_cookie **pcpp, pgcnt_t n, uint_t kflags)
{
struct devmap_pmem_cookie *pcp;
if ((*pcpp = kmem_zalloc(sizeof (struct devmap_pmem_cookie),
kflags)) == NULL)
return (DDI_FAILURE);
pcp = *pcpp;
if ((pcp->dp_vnp =
kmem_zalloc(sizeof (vnode_t), kflags)) == NULL) {
kmem_free(pcp, sizeof (struct devmap_pmem_cookie));
return (DDI_FAILURE);
}
if ((pcp->dp_pparray =
kmem_zalloc(n * sizeof (page_t *), kflags)) == NULL) {
kmem_free(pcp->dp_vnp, sizeof (vnode_t));
kmem_free(pcp, sizeof (struct devmap_pmem_cookie));
return (DDI_FAILURE);
}
return (DDI_SUCCESS);
}
/* Try to lock down n pages resource for current project. */
static int
pmem_lock(pgcnt_t n, kproject_t **prjpp)
{
mutex_enter(&curproc->p_lock);
if (i_ddi_incr_locked_memory(curproc, NULL, NULL, NULL,
ptob(n)) != 0) {
mutex_exit(&curproc->p_lock);
return (DDI_FAILURE);
}
/* Store this project in cookie for later lock/unlock. */
*prjpp = curproc->p_task->tk_proj;
mutex_exit(&curproc->p_lock);
return (DDI_SUCCESS);
}
/* To check if all the pages in a large page are freed. */
static int
lpg_isfree(pmem_lpg_t *plp)
{
uint_t i;
for (i = 0; i < BT_BITOUL(pmem_pgcnt); i++)
if (plp->pl_bitmap[i] != BT_ULMAXMASK)
return (0);
/* All 1 means all pages are freed. */
return (1);
}
/*
* Using pp to get the associated large page allocation record, searching in
* the splp linked list with *last as the heuristic pointer. Return NULL if
* not found.
*/
static pmem_lpg_t *
pmem_lpg_get(pmem_lpg_t *splp, page_t *pp, pmem_lpg_t **last)
{
pmem_lpg_t *plp;
pgcnt_t root_pfn;
ASSERT(pp);
if (splp == NULL)
return (NULL);
root_pfn = page_pptonum(pp) & ~(pmem_pgcnt - 1);
/* Try last winner first. */
if (*last && root_pfn == page_pptonum((*last)->pl_pp))
goto pl_found;
/* Else search the whole pmem_lpg list. */
for (plp = splp; root_pfn != page_pptonum(plp->pl_pp); ) {
plp = plp->pl_next;
if (plp == splp) {
plp = NULL;
break;
}
ASSERT(plp->pl_pp);
}
*last = plp;
pl_found:
return (*last);
}
/*
* Remove one pmem_lpg plp from the oplpp list.
*/
static void
pmem_lpg_sub(pmem_lpg_t **oplpp, pmem_lpg_t *plp)
{
if (*oplpp == plp)
*oplpp = plp->pl_next; /* go to next pmem_lpg */
if (*oplpp == plp)
*oplpp = NULL; /* pmem_lpg list is gone */
else {
plp->pl_prev->pl_next = plp->pl_next;
plp->pl_next->pl_prev = plp->pl_prev;
}
plp->pl_prev = plp->pl_next = plp; /* make plp a list of one */
}
/*
* Concatenate page list nplpp onto the end of list plpp.
*/
static void
pmem_lpg_concat(pmem_lpg_t **plpp, pmem_lpg_t **nplpp)
{
pmem_lpg_t *s1p, *s2p, *e1p, *e2p;
if (*nplpp == NULL) {
return;
}
if (*plpp == NULL) {
*plpp = *nplpp;
return;
}
s1p = *plpp;
e1p = s1p->pl_prev;
s2p = *nplpp;
e2p = s2p->pl_prev;
s1p->pl_prev = e2p;
e2p->pl_next = s1p;
e1p->pl_next = s2p;
s2p->pl_prev = e1p;
}
/*
* Allocate and initialize the allocation record of one large page, the init
* value is 'allocated'.
*/
static pmem_lpg_t *
pmem_lpg_alloc(uint_t kflags)
{
pmem_lpg_t *plp;
ASSERT(pmem_pgcnt % BT_NBIPUL == 0);
plp = kmem_zalloc(sizeof (pmem_lpg_t), kflags);
if (plp == NULL)
return (NULL);
plp->pl_bitmap = kmem_zalloc(BT_SIZEOFMAP(pmem_pgcnt), kflags);
if (plp->pl_bitmap == NULL) {
kmem_free(plp, sizeof (*plp));
return (NULL);
}
plp->pl_next = plp->pl_prev = plp;
return (plp);
}
/* Free one allocation record pointed by oplp. */
static void
pmem_lpg_free(pmem_lpg_t **headp, pmem_lpg_t *plp)
{
if (*headp == plp)
*headp = plp->pl_next; /* go to next pmem_lpg_t */
if (*headp == plp)
*headp = NULL; /* this list is gone */
else {
plp->pl_prev->pl_next = plp->pl_next;
plp->pl_next->pl_prev = plp->pl_prev;
}
kmem_free(plp->pl_bitmap, BT_SIZEOFMAP(pmem_pgcnt));
kmem_free(plp, sizeof (*plp));
}
/* Free one large page headed by spp from pmem_mpool. */
static void
lpg_free(page_t *spp)
{
page_t *pp1 = spp;
uint_t i;
ASSERT(MUTEX_HELD(&pmem_mutex));
for (i = 0; i < pmem_pgcnt; i++) {
/* Break pp1 from pmem_mpool. */
page_sub(&pmem_mpool, pp1);
pp1++;
}
/* Free pages in this large page. */
page_free_pages(spp);
page_unresv(pmem_pgcnt);
pmem_nmpages -= pmem_pgcnt;
ASSERT((pmem_nmpages && pmem_mpool) || (!pmem_nmpages && !pmem_mpool));
}
/* Put n pages in *ppp list back into pmem_mpool. */
static void
mpool_append(page_t **ppp, pgcnt_t n)
{
ASSERT(MUTEX_HELD(&pmem_mutex));
/* Put back pages. */
page_list_concat(&pmem_mpool, ppp);
pmem_nmpages += n;
ASSERT((pmem_nmpages && pmem_mpool) || (!pmem_nmpages && !pmem_mpool));
}
/*
* Try to grab MIN(pmem_nmpages, n) pages from pmem_mpool, put them into *ppp
* list, and return the number of grabbed pages.
*/
static pgcnt_t
mpool_break(page_t **ppp, pgcnt_t n)
{
pgcnt_t i;
ASSERT(MUTEX_HELD(&pmem_mutex));
/* Grab the pages. */
i = MIN(pmem_nmpages, n);
*ppp = pmem_mpool;
page_list_break(ppp, &pmem_mpool, i);
pmem_nmpages -= i;
ASSERT((pmem_nmpages && pmem_mpool) || (!pmem_nmpages && !pmem_mpool));
return (i);
}
/*
* Create n large pages, lpages and plpp contains the number of small pages and
* allocation records list respectively.
*/
static int
lpp_create(page_t **lppp, pgcnt_t n, pgcnt_t *lpages, pmem_lpg_t **plpp,
vnode_t *vnp, u_offset_t *offp, uint_t kflags)
{
pgcnt_t i;
pmem_lpg_t *plp;
page_t *pp;
for (i = 0, *lpages = 0; i < n; i++) {
/* Allocte one large page each time. */
pp = page_create_va_large(vnp, *offp, pmem_lpgsize,
PG_EXCL, &pmem_seg, (caddr_t)(uintptr_t)*offp, NULL);
if (pp == NULL)
break;
*offp += pmem_lpgsize;
page_list_concat(lppp, &pp);
*lpages += pmem_pgcnt;
/* Add one allocation record for this large page. */
if ((plp = pmem_lpg_alloc(kflags)) == NULL)
return (DDI_FAILURE);
plp->pl_pp = pp;
pmem_lpg_concat(plpp, &plp);
}
return (DDI_SUCCESS);
}
/*
* Break the last r small pages from the large page list *lppp (with totally n
* small pages) and put them into pmem_mpool.
*/
static void
lpp_break(page_t **lppp, pgcnt_t n, pgcnt_t r, pmem_lpg_t *oplp)
{
page_t *pp, *pp1;
pgcnt_t i;
pmem_lpg_t *plp;
if (r == 0)
return;
ASSERT(*lppp != NULL && r < pmem_pgcnt);
page_list_break(lppp, &pp, n - r);
/* The residual should reside in the last large page. */
plp = oplp->pl_prev;
/* IOunlock and hashout the residual pages. */
for (pp1 = pp, i = 0; i < r; i++) {
page_io_unlock(pp1);
page_hashout(pp1, NULL);
/* Mark this page as free. */
BT_SET(plp->pl_bitmap, PFIND(pp1));
pp1 = pp1->p_next;
}
ASSERT(pp1 == pp);
/* Put these residual pages into memory pool. */
mutex_enter(&pmem_mutex);
mpool_append(&pp, r);
mutex_exit(&pmem_mutex);
}
/* Freeing large pages in lpp and the associated allocation records in plp. */
static void
lpp_free(page_t *lpp, pgcnt_t lpgs, pmem_lpg_t **plpp)
{
pgcnt_t i, j;
page_t *pp = lpp, *pp1;
pmem_lpg_t *plp1, *plp2;
for (i = 0; i < lpgs; i++) {
for (j = 0; j < pmem_pgcnt; j++) {
/* IO unlock and hashout this small page. */
page_io_unlock(pp);
page_hashout(pp, NULL);
pp1 = pp->p_next;
pp->p_prev = pp->p_next = pp;
pp = pp1;
}
/* Free one large page at one time. */
page_free_pages(lpp);
lpp = pp;
}
/* Free associate pmem large page allocation records. */
for (plp1 = *plpp; *plpp; plp1 = plp2) {
plp2 = plp1->pl_next;
pmem_lpg_free(plpp, plp1);
}
}
/*
* IOlock and hashin all pages in tlist, associate them with vnode *pvnp
* and offset starting with *poffp. Update allocation records accordingly at
* the same time.
*/
static void
tlist_in(page_t *tlist, pgcnt_t tpages, vnode_t *pvnp, u_offset_t *poffp)
{
page_t *pp;
pgcnt_t i = 0;
pmem_lpg_t *plp, *last_pl = NULL;
ASSERT(MUTEX_HELD(&pmem_mutex));
for (pp = tlist; i < tpages; i++) {
ASSERT(FROM_LPG(pp));
page_io_lock(pp);
(void) page_hashin(pp, pvnp, *poffp, NULL);
plp = pmem_lpg_get(pmem_occ_lpgs, pp, &last_pl);
/* Mark this page as allocated. */
BT_CLEAR(plp->pl_bitmap, PFIND(pp));
*poffp += PAGESIZE;
pp = pp->p_next;
}
ASSERT(pp == tlist);
}
/*
* IOunlock and hashout all pages in tlist, update allocation records
* accordingly at the same time.
*/
static void
tlist_out(page_t *tlist, pgcnt_t tpages)
{
page_t *pp;
pgcnt_t i = 0;
pmem_lpg_t *plp, *last_pl = NULL;
ASSERT(MUTEX_HELD(&pmem_mutex));
for (pp = tlist; i < tpages; i++) {
ASSERT(FROM_LPG(pp));
page_io_unlock(pp);
page_hashout(pp, NULL);
plp = pmem_lpg_get(pmem_occ_lpgs, pp, &last_pl);
/* Mark this page as free. */
BT_SET(plp->pl_bitmap, PFIND(pp));
pp = pp->p_next;
}
ASSERT(pp == tlist);
}