sparcv9/sun4u/bitmap.c

	bitmap.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * 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 1999-2002 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <sys/cpr.h>
#include <sys/fs/ufs_fs.h>
#include <sys/prom_plat.h>
#include "cprboot.h"


/*
 * max space for a copy of physavail data
 * prop size is usually 80 to 128 bytes
 */
#define PA_BUFSIZE  1024

#define CB_SETBIT   1
#define CB_ISSET    2
#define CB_ISCLR    3

/*
 * globals
 */
int cb_nbitmaps;

/*
 * file scope
 */
static arange_t *cb_physavail;
static char pabuf[PA_BUFSIZE];
static caddr_t high_virt;

static cbd_t cb_bmda[CPR_MAX_BMDESC];
static int tracking_init;


static int
cb_bitop(pfn_t ppn, int op)
{
    int rel, rval = 0;
    char *bitmap;
    cbd_t *dp;

    for (dp = cb_bmda; dp->cbd_size; dp++) {
        if (PPN_IN_RANGE(ppn, dp)) {
            bitmap = (char *)dp->cbd_reg_bitmap;
            rel = ppn - dp->cbd_spfn;
            if (op == CB_SETBIT)
                setbit(bitmap, rel);
            else if (op == CB_ISSET)
                rval = isset(bitmap, rel);
            else if (op == CB_ISCLR)
                rval = isclr(bitmap, rel);
            break;
        }
    }

    return (rval);
}


/*
 * count pages that are isolated from the kernel
 * within each available range
 */
static void
count_free_pages(void)
{
    arange_t *arp;
    pfn_t bitno;
    int cnt;

    for (arp = cb_physavail; arp->high; arp++) {
        cnt = 0;
        for (bitno = arp->low; bitno <= arp->high; bitno++) {
            if (cb_bitop(bitno, CB_ISCLR))
                cnt++;
        }
        arp->nfree = cnt;
    }
}


/*
 * scan the physavail list for a page
 * that doesn't clash with the kernel
 */
static pfn_t
search_phav_pages(void)
{
    static arange_t *arp;
    static pfn_t bitno;
    int rescan;

    if (arp == NULL) {
        count_free_pages();
        arp = cb_physavail;
        bitno = arp->low;
    }

    /*
     * begin scanning from the previous position and if the scan
     * reaches the end of the list, scan a second time from the top;
     * nfree is checked to eliminate scanning overhead when most
     * of the available space gets used up.  when a page is found,
     * set a bit so the page wont be found by another scan.
     */
    for (rescan = 0; rescan < 2; rescan++) {
        for (; arp->high; bitno = (++arp)->low) {
            if (arp->nfree == 0)
                continue;
            for (; bitno <= arp->high; bitno++) {
                if (cb_bitop(bitno, CB_ISCLR)) {
                    (void) cb_bitop(bitno, CB_SETBIT);
                    arp->nfree--;
                    return (bitno++);
                }
            }
        }
        arp = cb_physavail;
        bitno = arp->low;
    }

    return (PFN_INVALID);
}


/*
 * scan statefile buffer pages for reusable tmp space
 */
static pfn_t
search_buf_pages(void)
{
    size_t coff, src_base;
    static size_t lboff;
    pfn_t ppn;

    if (tracking_init == 0)
        return (PFN_INVALID);

    /*
     * when scanning the list of statefile buffer ppns, we know that
     * all pages from lboff to the page boundary of buf_offset have
     * already been restored; when the associated page bit is clear,
     * that page is isolated from the kernel and we can reuse it for
     * tmp space; otherwise, when SF_DIFF_PPN indicates a page had
     * been moved, we know the page bit was previously clear and
     * later set, and we can reuse the new page.
     */
    src_base = sfile.buf_offset & MMU_PAGEMASK;
    while (lboff < src_base) {
        coff = lboff;
        lboff += MMU_PAGESIZE;
        ppn = SF_ORIG_PPN(coff);
        if (cb_bitop(ppn, CB_ISCLR)) {
            (void) cb_bitop(ppn, CB_SETBIT);
            SF_STAT_INC(recycle);
            return (ppn);
        } else if (SF_DIFF_PPN(coff)) {
            SF_STAT_INC(recycle);
            return (SF_BUF_PPN(coff));
        }
    }

    return (PFN_INVALID);
}


/*
 * scan physavail and statefile buffer page lists
 * for a page that doesn't clash with the kernel
 */
pfn_t
find_apage(void)
{
    pfn_t ppn;

    ppn = search_phav_pages();
    if (ppn != PFN_INVALID)
        return (ppn);
    ppn = search_buf_pages();
    if (ppn != PFN_INVALID)
        return (ppn);

    prom_printf("\n%s: ran out of available/free pages!\n%s\n",
        prog, rsvp);
    cb_exit_to_mon();

    /* NOTREACHED */
    return (PFN_INVALID);
}


/*
 * reserve virt range, find available phys pages,
 * and map-in each phys starting at vaddr
 */
static caddr_t
map_free_phys(caddr_t vaddr, size_t size, char *name)
{
    int pages, ppn, err;
    physaddr_t phys;
    caddr_t virt;
    char *str;

    str = "map_free_phys";
    virt = prom_claim_virt(size, vaddr);
    CB_VPRINTF(("\n%s: claim vaddr 0x%x, size 0x%x, ret 0x%x\n",
        str, vaddr, size, virt));
    if (virt != vaddr) {
        prom_printf("\n%s: cant reserve (0x%p - 0x%p) for \"%s\"\n",
            str, vaddr, vaddr + size, name);
        return (virt);
    }

    for (pages = mmu_btop(size); pages--; virt += MMU_PAGESIZE) {
        /*
         * map virt page to free phys
         */
        ppn = find_apage();
        phys = PN_TO_ADDR(ppn);

        err = prom_map_phys(-1, MMU_PAGESIZE, virt, phys);
        if (err || verbose) {
            prom_printf("    map virt 0x%p, phys 0x%lx, "
                "ppn 0x%lx, ret %d\n", virt, phys, ppn, err);
        }
        if (err)
            return ((caddr_t)ERR);
    }

    return (vaddr);
}


/*
 * check bitmap desc and relocate bitmap data
 * to pages isolated from the kernel
 *
 * sets globals:
 *  high_virt
 */
int
cb_set_bitmap(void)
{
    size_t bmda_size, all_bitmap_size, alloc_size;
    caddr_t newvirt, src, dst, base;
    cbd_t *dp;
    char *str;

    str = "cb_set_bitmap";
    CB_VPRINTF((ent_fmt, str, entry));

    /*
     * max is checked in the cpr module;
     * this condition should never occur
     */
    if (cb_nbitmaps > (CPR_MAX_BMDESC - 1)) {
        prom_printf("%s: too many bitmap descriptors %d, max %d\n",
            str, cb_nbitmaps, (CPR_MAX_BMDESC - 1));
        return (ERR);
    }

    /*
     * copy bitmap descriptors to aligned space, check magic numbers,
     * and set the total size of all bitmaps
     */
    bmda_size = cb_nbitmaps * sizeof (cbd_t);
    src = SF_DATA();
    bcopy(src, cb_bmda, bmda_size);
    base = src + bmda_size;
    all_bitmap_size = 0;
    for (dp = cb_bmda; dp < &cb_bmda[cb_nbitmaps]; dp++) {
        if (dp->cbd_magic != CPR_BITMAP_MAGIC) {
            prom_printf("%s: bad magic 0x%x, expect 0x%x\n",
                str, dp->cbd_magic, CPR_BITMAP_MAGIC);
            return (ERR);
        }
        all_bitmap_size += dp->cbd_size;
        dp->cbd_reg_bitmap = (cpr_ptr)base;
        base += dp->cbd_size;
    }

    /*
     * reserve new space for bitmaps
     */
    alloc_size = PAGE_ROUNDUP(all_bitmap_size);
    if (verbose || CPR_DBG(7)) {
        prom_printf("%s: nbitmaps %d, bmda_size 0x%lx\n",
            str, cb_nbitmaps);
        prom_printf("%s: all_bitmap_size 0x%lx, alloc_size 0x%lx\n",
            str, all_bitmap_size, alloc_size);
    }
    high_virt = (caddr_t)CB_HIGH_VIRT;
    newvirt = map_free_phys(high_virt, alloc_size, "bitmaps");
    if (newvirt != high_virt)
        return (ERR);

    /*
     * copy the bitmaps, clear any unused space trailing them,
     * and set references into the new space
     */
    base = src + bmda_size;
    dst = newvirt;
    bcopy(base, dst, all_bitmap_size);
    if (alloc_size > all_bitmap_size)
        bzero(dst + all_bitmap_size, alloc_size - all_bitmap_size);
    for (dp = cb_bmda; dp->cbd_size; dp++) {
        dp->cbd_reg_bitmap = (cpr_ptr)dst;
        dst += dp->cbd_size;
    }

    /* advance past all the bitmap data */
    SF_ADV(bmda_size + all_bitmap_size);
    high_virt += alloc_size;

    return (0);
}


/*
 * create a new stack for cprboot;
 * this stack is used to avoid clashes with kernel pages and
 * to avoid exceptions while remapping cprboot virt pages
 */
int
cb_get_newstack(void)
{
    caddr_t newstack;

    CB_VENTRY(cb_get_newstack);
    newstack = map_free_phys((caddr_t)CB_STACK_VIRT,
        CB_STACK_SIZE, "new stack");
    if (newstack != (caddr_t)CB_STACK_VIRT)
        return (ERR);
    return (0);
}


/*
 * since kernel phys pages span most of the installed memory range,
 * some statefile buffer pages will likely clash with the kernel
 * and need to be moved before kernel pages are restored; a list
 * of buf phys page numbers is created here and later updated as
 * buf pages are moved
 *
 * sets globals:
 *  sfile.buf_map
 *  tracking_init
 */
int
cb_tracking_setup(void)
{
    pfn_t ppn, lppn;
    uint_t *imap;
    caddr_t newvirt;
    size_t size;
    int pages;

    CB_VENTRY(cb_tracking_setup);

    pages = mmu_btop(sfile.size);
    size = PAGE_ROUNDUP(pages * sizeof (*imap));
    newvirt = map_free_phys(high_virt, size, "buf tracking");
    if (newvirt != high_virt)
        return (ERR);
    sfile.buf_map = (uint_t *)newvirt;
    high_virt += size;

    /*
     * create identity map of sfile.buf phys pages
     */
    imap = sfile.buf_map;
    lppn = sfile.low_ppn + pages;
    for (ppn = sfile.low_ppn; ppn < lppn; ppn++, imap++)
        *imap = (uint_t)ppn;
    tracking_init = 1;

    return (0);
}


/*
 * get "available" prop from /memory node
 *
 * sets globals:
 *  cb_physavail
 */
int
cb_get_physavail(void)
{
    int len, glen, scnt, need, space;
    char *str, *pdev, *mem_prop;
    dnode_t mem_node;
    physaddr_t phys;
    pgcnt_t pages;
    arange_t *arp;
    pphav_t *pap;
    size_t size;
    pfn_t ppn;
    int err;

    str = "cb_get_physavail";
    CB_VPRINTF((ent_fmt, str, entry));

    /*
     * first move cprboot pages off the physavail list
     */
    size = PAGE_ROUNDUP((uintptr_t)_end) - (uintptr_t)_start;
    ppn = cpr_vatopfn((caddr_t)_start);
    phys = PN_TO_ADDR(ppn);
    err = prom_claim_phys(size, phys);
    CB_VPRINTF(("    text/data claim (0x%lx - 0x%lx) = %d\n",
        ppn, ppn + mmu_btop(size) - 1, err));
    if (err)
        return (ERR);

    pdev = "/memory";
    mem_node = prom_finddevice(pdev);
    if (mem_node == OBP_BADNODE) {
        prom_printf("%s: cant find \"%s\" node\n", str, pdev);
        return (ERR);
    }
    mem_prop = "available";

    /*
     * prop data is treated as a struct array;
     * verify pabuf has enough room for the array
     * in the original and converted forms
     */
    len = prom_getproplen(mem_node, mem_prop);
    scnt = len / sizeof (*pap);
    need = len + (sizeof (*arp) * (scnt + 1));
    space = sizeof (pabuf);
    CB_VPRINTF(("    %s node 0x%x, len %d\n", pdev, mem_node, len));
    if (len == -1 || need > space) {
        prom_printf("\n%s: bad \"%s\" length %d, min %d, max %d\n",
            str, mem_prop, len, need, space);
        return (ERR);
    }

    /*
     * read-in prop data and clear trailing space
     */
    glen = prom_getprop(mem_node, mem_prop, pabuf);
    if (glen != len) {
        prom_printf("\n%s: %s,%s: expected len %d, got %d\n",
            str, mem_node, mem_prop, len, glen);
        return (ERR);
    }
    bzero(&pabuf[len], space - len);

    /*
     * convert the physavail list in place
     * from (phys_base, phys_size) to (low_ppn, high_ppn)
     */
    if (verbose)
        prom_printf("\nphysavail list:\n");
    cb_physavail = (arange_t *)pabuf;
    arp = cb_physavail + scnt - 1;
    pap = (pphav_t *)cb_physavail + scnt - 1;
    for (; scnt--; pap--, arp--) {
        pages = mmu_btop(pap->size);
        arp->low = ADDR_TO_PN(pap->base);
        arp->high = arp->low + pages - 1;
        if (verbose) {
            prom_printf("  %d: (0x%lx - 0x%lx),\tpages %d\n",
                (int)(arp - cb_physavail),
                arp->low, arp->high, (arp->high - arp->low + 1));
        }
    }

    return (0);
}


/*
 * search for an available phys page,
 * copy the old phys page to the new one
 * and remap the virt page to the new phys
 */
static int
move_page(caddr_t vaddr, pfn_t oldppn)
{
    physaddr_t oldphys, newphys;
    pfn_t newppn;
    int err;

    newppn = find_apage();
    newphys = PN_TO_ADDR(newppn);
    oldphys = PN_TO_ADDR(oldppn);
    CB_VPRINTF(("    remap vaddr 0x%p, old 0x%x/0x%x, new 0x%x/0x%x\n",
        vaddr, oldppn, oldphys, newppn, newphys));
    phys_xcopy(oldphys, newphys, MMU_PAGESIZE);
    err = prom_remap(MMU_PAGESIZE, vaddr, newphys);
    if (err)
        prom_printf("\nmove_page: remap error\n");
    return (err);
}


/*
 * physically relocate any text/data pages that clash
 * with the kernel; since we're already running on
 * a new stack, the original stack area is skipped
 */
int
cb_relocate(void)
{
    int is_ostk, is_clash, clash_cnt, ok_cnt;
    char *str, *desc, *skip_fmt;
    caddr_t ostk_low, ostk_high;
    caddr_t virt, saddr, eaddr;
    pfn_t ppn;

    str = "cb_relocate";
    CB_VPRINTF((ent_fmt, str, entry));

    ostk_low  = (caddr_t)&estack - CB_STACK_SIZE;
    ostk_high = (caddr_t)&estack - MMU_PAGESIZE;
    saddr = (caddr_t)_start;
    eaddr = (caddr_t)PAGE_ROUNDUP((uintptr_t)_end);

    install_remap();

    skip_fmt = "    skip  vaddr 0x%p, clash=%d, %s\n";
    clash_cnt = ok_cnt = 0;
    ppn = cpr_vatopfn(saddr);

    for (virt = saddr; virt < eaddr; virt += MMU_PAGESIZE, ppn++) {
        is_clash = (cb_bitop(ppn, CB_ISSET) != 0);
        if (is_clash)
            clash_cnt++;
        else
            ok_cnt++;

        is_ostk = (virt >= ostk_low && virt <= ostk_high);
        if (is_ostk)
            desc = "orig stack";
        else
            desc = "text/data";

        /*
         * page logic:
         *
         * if (original stack page)
         *  clash doesn't matter, just skip the page
         * else (not original stack page)
         *  if (no clash)
         *      setbit to avoid later alloc and overwrite
         *  else (clash)
         *      relocate phys page
         */
        if (is_ostk) {
            CB_VPRINTF((skip_fmt, virt, is_clash, desc));
        } else if (is_clash == 0) {
            CB_VPRINTF((skip_fmt, virt, is_clash, desc));
            (void) cb_bitop(ppn, CB_SETBIT);
        } else if (move_page(virt, ppn))
            return (ERR);
    }
    CB_VPRINTF(("%s: total %d, clash %d, ok %d\n",
        str, clash_cnt + ok_cnt, clash_cnt, ok_cnt));

    /*
     * free original stack area for reuse
     */
    ppn = cpr_vatopfn(ostk_low);
    prom_free_phys(CB_STACK_SIZE, PN_TO_ADDR(ppn));
    CB_VPRINTF(("%s: free old stack (0x%lx - 0x%lx)\n",
        str, ppn, ppn + mmu_btop(CB_STACK_SIZE) - 1));

    return (0);
}