backup/dump/dumponline.c

/*
 * 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 (c) 1991,1996,1998 by Sun Microsystems, Inc.
 * All rights reserved.
 */

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

#include "dump.h"
#include <math.h>
#include <limits.h>

/*
 * Uncomment if using mmap'ing of files for pre-fetch.
 * #define ENABLE_MMAP 1
 */

struct inodesc {
    ino_t   id_inumber;     /* inode number */
    long    id_gen;         /* generation number */
    struct inodesc *id_next;    /* next on linked list */
};

static struct inodesc   ilist;      /* list of used inodesc structs */
static struct inodesc   *last;      /* last inodesc init'd or matched */
static struct inodesc   *freeinodesc;   /* free list of inodesc structs */
static struct inodesc   **ialloc;   /* allocated chunks, for freeing */
static int      nchunks;    /* number of allocations */

#ifdef ENABLE_MMAP /* XXX part of mmap support */
/*
 * If an mmap'ed file is truncated as it is being dumped or
 * faulted in, we are delivered a SIGBUS.
 */
static jmp_buf  truncate_buf;
static void (*savebus)();
static int  incopy;

#ifdef __STDC__
static void onsigbus(int);
#else
static void onsigbus();
#endif

#endif  /* ENABLE_MMAP */

#ifdef DEBUG
extern int xflag;
#endif

#ifdef ENABLE_MMAP /* XXX part of mmap support */
static void
onsigbus(sig)
    int sig;
{
    if (!incopy) {
        dumpabort();
        /*NOTREACHED*/
    }
    incopy = 0;
    longjmp(truncate_buf, 1);
    /*NOTREACHED*/
}
#endif  /* ENABLE_MMAP */

void
#ifdef __STDC__
allocino(void)
#else
allocino()
#endif
{
    ino_t maxino;
    size_t nused;

    maxino = (unsigned)(sblock->fs_ipg * sblock->fs_ncg);
    if (maxino > ULONG_MAX) {
        msg(gettext("allocino: filesystem too large\n"));
        dumpabort();
        /*NOTREACHED*/
    }
    /* LINTED maxino guaranteed to fit into a size_t by above test */
    nused =  maxino - sblock->fs_cstotal.cs_nifree;
    freeinodesc = (struct inodesc *)xcalloc(nused, sizeof (*freeinodesc));
    if (freeinodesc == (struct inodesc *)0) {
        msg(gettext("%s: out of memory\n"), "allocino");
        dumpabort();
        /*NOTREACHED*/
    }
    last = &ilist;
    ialloc =
        (struct inodesc **)xmalloc(2*sizeof (*ialloc));
    ialloc[0] = freeinodesc;
    ialloc[1] = (struct inodesc *)0;
    nchunks = 1;
}

void
#ifdef __STDC__
freeino(void)
#else
freeino()
#endif
{
    int i;

    if (ialloc == (struct inodesc **)0)
        return;
    for (i = 0; i < nchunks; i++)
        if (ialloc[i] != 0)
            free(ialloc[i]);
    free(ialloc);
    ialloc = (struct inodesc **)0;
}

void
resetino(ino)
    ino_t   ino;
{
    last = ilist.id_next;
    while (last && last->id_inumber < ino)
        last = last->id_next;
}

char *
unrawname(cp)
    char *cp;
{
    char *dp;
    extern char *getfullblkname();

    dp = getfullblkname(cp);
    if (dp == 0)
        return (0);
    if (*dp == '\0') {
        free(dp);
        return (0);
    }
    if (dp == cp)       /* caller wants to always free() dp */
        dp = strdup(cp);

    return (dp);
}

/*
 * Determine if specified device is mounted at
 * specified mount point.  Returns 1 if mounted,
 * 0 if not mounted, -1 on error.
 */
int
lf_ismounted(devname, dirname)
    char    *devname;   /* name of device (raw or block) */
    char    *dirname;   /* name of f/s mount point */
{
    struct stat64 st;
    char    *blockname; /* name of block device */
    dev_t   dev;
    int saverr;

    if ((blockname = unrawname(devname)) == NULL) {
        msg(gettext("Cannot obtain block name from `%s'\n"), devname);
        return (-1);
    }
    if (stat64(blockname, &st) < 0) {
        saverr = errno;
        msg(gettext("Cannot obtain status of device `%s': %s\n"),
            blockname, strerror(saverr));
        free(blockname);
        return (-1);
    }
    free(blockname);
    dev = st.st_rdev;
    if (stat64(dirname, &st) < 0) {
        saverr = errno;
        msg(gettext("Cannot obtain status of device `%s': %s\n"),
            dirname, strerror(saverr));
        return (-1);
    }
    if (dev == st.st_dev)
        return (1);
    return (0);
}

#ifdef ENABLE_MMAP /* XXX mapped-file support */
#define MINMAPSIZE  1024*1024
#define MAXMAPSIZE  1024*1024*32

static caddr_t  mapbase;    /* base of mapped data */
static caddr_t  mapend;     /* last byte of mapped data */
static size_t   mapsize;    /* amount of mapped data */
/*
 * Map a file prior to dumping and start faulting in its
 * pages.  Stop if we catch a signal indicating our turn
 * to dump has arrived.  If the file is truncated out from
 * under us, immediately return.
 * NB:  the base of the mapped data may not coincide
 * exactly to the requested offset, due to alignment
 * constraints.
 */
caddr_t
mapfile(fd, offset, bytes, fetch)
    int fd;
    off_t   offset;     /* offset within file */
    off_t   bytes;      /* number of bytes to map */
    int fetch;      /* start faulting in pages */
{
    /*LINTED [c used during pre-fetch faulting]*/
    volatile char c, *p;
    int stride = (int)sysconf(_SC_PAGESIZE);
    extern int caught;      /* pre-fetch until set */
    caddr_t mapstart;       /* beginning of file's mapped data */
    off_t   mapoffset;      /* page-aligned offset */
    int saverr;

    mapbase = mapend = (caddr_t)0;

    if (bytes == 0)
        return ((caddr_t)0);
    /*
     * mmap the file for reading
     */
    mapoffset = offset & ~(stride - 1);
    /* LINTED: "bytes" will always fit into a size_t */
    mapsize = bytes + (offset - mapoffset);
    if (mapsize > MAXMAPSIZE)
        mapsize = MAXMAPSIZE;
    while ((mapbase = mmap((caddr_t)0, mapsize, PROT_READ,
        MAP_SHARED, fd, mapoffset)) == (caddr_t)-1 &&
        errno == ENOMEM && mapsize >= MINMAPSIZE) {
        /*
         * Due to address space limitations, we
         * may not be able to map as much as we want.
         */
        mapsize /= 2;   /* exponential back-off */
    }

    if (mapbase == (caddr_t)-1) {
        saverr = errno;
        msg(gettext("Cannot map file at inode `%lu' into memory: %s\n"),
            ino, strerror(saverr));
        /* XXX why not call dumpailing() here? */
        if (!query(gettext(
        "Do you want to attempt to continue? (\"yes\" or \"no\") "))) {
            dumpabort();
            /*NOTREACHED*/
        }
        mapbase = (caddr_t)0;
        return ((caddr_t)0);
    }

    (void) madvise(mapbase, mapsize, MADV_SEQUENTIAL);
    mapstart = mapbase + (offset - mapoffset);
    mapend = mapbase + (mapsize - 1);

    if (!fetch)
        return (mapstart);

    if (setjmp(truncate_buf) == 0) {
        savebus = signal(SIGBUS, onsigbus);
        /*
         * Touch each page to pre-fetch by faulting.  At least
         * one of c or *p must be declared volatile, lest the
         * optimizer eliminate the assignment in the loop.
         */
        incopy = 1;
        for (p = mapbase; !caught && p <= mapend; p += stride) {
            /* LINTED: c is used for its side-effects */
            c = *p;
        }
        incopy = 0;
    }
#ifdef DEBUG
    else
        /* XGETTEXT:  #ifdef DEBUG only */
        msg(gettext(
            "FILE TRUNCATED (fault): Interrupting pre-fetch\n"));
#endif
    (void) signal(SIGBUS, savebus);
    return (mapstart);
}

void
#ifdef __STDC__
unmapfile(void)
#else
unmapfile()
#endif
{
    if (mapbase) {
        /* XXX we're unmapping it, so what does this gain us? */
        (void) msync(mapbase, mapsize, MS_ASYNC|MS_INVALIDATE);
        (void) munmap(mapbase, mapsize);
        mapbase = (caddr_t)0;
    }
}
#endif  /* ENABLE_MMAP */

void
#ifdef __STDC__
activepass(void)
#else
activepass()
#endif
{
    static int passno = 1;          /* active file pass number */
    char *ext, *old;
    char buf[3000];
    static char defext[] = ".retry";

    if (pipeout) {
        msg(gettext("Cannot re-dump active files to `%s'\n"), tape);
        dumpabort();
        /*NOTREACHED*/
    }

    if (active > 1)
        (void) snprintf(buf, sizeof (buf), gettext(
            "%d files were active and will be re-dumped\n"), active);
    else
        (void) snprintf(buf, sizeof (buf), gettext(
            "1 file was active and will be re-dumped\n"));
    msg(buf);

    doingactive++;
    active = 0;
    reset();            /* reset tape params */
    spcl.c_ddate = spcl.c_date; /* chain with last dump/pass */

    /*
     * If archiving, create a new
     * archive file.
     */
    if (archivefile) {
        old = archivefile;

        ext = strstr(old, defext);
        if (ext != (char *)NULL)
            *ext = '\0'; /* just want the base name */

        /* The two is for the trailing \0 and rounding up log10() */
        archivefile = xmalloc(strlen(old) + strlen(defext) +
            (int)log10((double)passno) + 2);

        /* Always fits */
        (void) sprintf(archivefile, "%s%s%d", old, defext, passno);
        free(old);
    }

    if (tapeout) {
        if (isrewind(to)) {
            /*
             * A "rewind" tape device.  When we do
             * the close, we will lose our position.
             * Be nice and switch volumes.
             */
            (void) snprintf(buf, sizeof (buf), gettext(
        "Warning - cannot dump active files to rewind device `%s'\n"),
                tape);
            msg(buf);
            close_rewind();
            changevol();
        } else {
            trewind();
            doposition = 0;
            filenum++;
        }
    } else {
        /*
         * Not a tape.  Do a volume switch.
         * This will advance to the next file
         * if using a sequence of files, next
         * diskette if using diskettes, or
         * let the user move the old file out
         * of the way.
         */
        close_rewind();
        changevol();    /* switch files */
    }
    (void) snprintf(buf, sizeof (buf), gettext(
        "Dumping active files (retry pass %d) to `%s'\n"), passno, tape);
    msg(buf);
    passno++;
}