]> git.wh0rd.org - dump.git/blobdiff - dump/tape.c
Use sys_clone under Linux to share I/O contexts between dump processes.
[dump.git] / dump / tape.c
index 66fc821cdaaab154898d8eb21f64233b47e935a9..edcf5d691925a6532dd71e8b30f75514d8190109 100644 (file)
  * 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.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *     This product includes software developed by the University of
- *     California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. 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.
  *
@@ -41,7 +37,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-       "$Id: tape.c,v 1.61 2002/01/25 14:59:53 stelian Exp $";
+       "$Id: tape.c,v 1.91 2009/06/18 09:50:54 stelian Exp $";
 #endif /* not lint */
 
 #include <config.h>
@@ -64,6 +60,11 @@ int    write(), read();
 #ifdef __linux__
 #include <sys/types.h>
 #include <sys/time.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h> /* for definition of BLKFLSBUF */
+#ifndef BLKFLSBUF      /* last resort... */
+#define BLKFLSBUF _IO(0x12, 97) /* Flush buffer cache.  */
+#endif
 #include <time.h>
 #endif
 #include <sys/param.h>
@@ -71,9 +72,6 @@ int    write(), read();
 #include <sys/wait.h>
 #include <sys/mtio.h>
 #ifdef __linux__
-#include <linux/fs.h>
-#undef atomic_read     /* this get wrongly defined in kernel */
-                       /* headers and we don't want it */
 #ifdef HAVE_EXT2FS_EXT2_FS_H
 #include <ext2fs/ext2_fs.h>
 #else
@@ -102,12 +100,17 @@ int    write(), read();
 #include <bzlib.h>
 #endif /* HAVE_BZLIB */
 
+#ifdef HAVE_LZO
+#include <minilzo.h>
+#endif /* HAVE_LZO */
+
 #include "dump.h"
 
 int    writesize;              /* size of malloc()ed buffer for tape */
 long   lastspclrec = -1;       /* tape block number of last written header */
 int    trecno = 0;             /* next record to write in current block */
-extern long blocksperfile;     /* number of blocks per output file */
+extern long *blocksperfiles;   /* number of blocks per output file(s) */
+long   blocksperfiles_current; /* current position in blocksperfiles */
 long   blocksthisvol;          /* number of blocks on current output file */
 extern int ntrec;              /* blocking factor on tape */
 extern int cartridge;
@@ -117,16 +120,21 @@ int       eot_code = 1;
 long long tapea_bytes = 0;     /* bytes_written at start of current volume */
 static int magtapeout;         /* output is really a tape */
 
-static ssize_t atomic_read __P((int, void *, size_t));
-static ssize_t atomic_write __P((int, const void *, size_t));
+static ssize_t dump_atomic_read __P((int, char *, size_t));
+static ssize_t dump_atomic_write __P((int, const char *, size_t));
+#ifdef WRITEDEBUG
 static void doslave __P((int, int, int));
+#else
+static void doslave __P((int, int));
+#endif
 static void enslave __P((void));
 static void flushtape __P((void));
 static void killall __P((void));
 static void rollforward __P((void));
 #ifdef USE_QFA
 static int GetTapePos __P((long long *));
-static void MkTapeString __P((struct s_spcl *, long long));
+static int MkTapeString __P((struct s_spcl *, long long));
+#define FILESQFAPOS    20
 #endif
 
 /*
@@ -138,7 +146,7 @@ static void MkTapeString __P((struct s_spcl *, long long));
  * The following structure defines the instruction packets sent to slaves.
  */
 struct req {
-       daddr_t dblk;
+       ext2_loff_t dblk;
        int count;
 };
 int reqsiz;
@@ -179,6 +187,41 @@ static sigjmp_buf jmpbuf;  /* where to jump to if we are ready when the */
 static int gtperr = 0;
 #endif
 
+/*
+ * Determine if we can use Linux' clone system call.  If so, call it
+ * with the CLONE_IO flag so that all processes will share the same I/O
+ * context, allowing the I/O schedulers to make better scheduling decisions.
+ */
+#ifdef __linux__
+/* first, pull in the header files that define sys_clone and CLONE_IO */
+#include <syscall.h>
+#define _GNU_SOURCE
+#include <sched.h>
+#include <unistd.h>
+#undef _GNU_SOURCE
+
+/* If either is not present, fall back on the fork behaviour */
+#if ! defined(SYS_clone) || ! defined (CLONE_IO)
+#define fork_clone_io fork
+#else /* SYS_clone */
+/* CLONE_IO is available, determine which version of sys_clone to use */
+#include <linux/version.h>
+/*
+ * Kernel 2.5.49 introduced two extra parameters to the clone system call.
+ * Neither is useful in our case, so this is easy to handle.
+ */
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,49)
+/* clone_flags, child_stack, parent_tidptr, child_tidptr */
+#define CLONE_ARGS SIGCHLD|CLONE_IO, 0, NULL, NULL
+#else
+#define CLONE_ARGS SIGCHLD|CLONE_IO, 0
+#endif /* LINUX_VERSION_CODE */
+pid_t fork_clone_io(void);
+#endif /* SYS_clone */
+#else /* __linux__ not defined */
+#define fork_clone_io fork
+#endif /* __linux__ */
+
 int
 alloctape(void)
 {
@@ -194,7 +237,7 @@ alloctape(void)
         * repositioning after stopping, i.e, streaming mode, where the gap is
         * variable, 0.30" to 0.45".  The gap is maximal when the tape stops.
         */
-       if (blocksperfile == 0 && !unlimited)
+       if (!blocksperfiles && !unlimited)
                tenths = (cartridge ? 16 : density == 625 ? 5 : 8);
        else {
                tenths = 0;
@@ -230,20 +273,20 @@ void
 writerec(const void *dp, int isspcl)
 {
 
-       slp->req[trecno].dblk = (daddr_t)0;
+       slp->req[trecno].dblk = (ext2_loff_t)0;
        slp->req[trecno].count = 1;
        /* XXX post increment triggers an egcs-1.1.2-12 bug on alpha/sparc */
        *(union u_spcl *)(*(nextblock)) = *(union u_spcl *)dp;
 
        /* Need to write it to the archive file */
-       if (Afile < 0 && isspcl && (spcl.c_type == TS_END))
-               Afile = -Afile;
-       if (Afile > 0) {
+       if (! AfileActive && isspcl && (spcl.c_type == TS_END))
+               AfileActive = 1;
+       if (AfileActive && Afile >= 0 && !(spcl.c_flags & DR_EXTATTRIBUTES)) {
                /* When we dump an inode which is not a directory,
                 * it means we ended the archive contents */
                if (isspcl && (spcl.c_type == TS_INODE) &&
                    ((spcl.c_dinode.di_mode & S_IFMT) != IFDIR))
-                       Afile = -Afile;
+                       AfileActive = 0;
                else {
                        union u_spcl tmp;
                        tmp = *(union u_spcl *)dp;
@@ -268,9 +311,10 @@ writerec(const void *dp, int isspcl)
 }
 
 void
-dumpblock(daddr_t blkno, int size)
+dumpblock(blk_t blkno, int size)
 {
-       int avail, tpblks, dblkno;
+       int avail, tpblks;
+       ext2_loff_t dblkno;
 
        dblkno = fsbtodb(sblock, blkno);
        tpblks = size >> tp_bshift;
@@ -314,7 +358,7 @@ tperror(int errnum)
 }
 
 static void
-sigpipe(int signo)
+sigpipe(UNUSED(int signo))
 {
 
        quit("Broken pipe\n");
@@ -335,7 +379,7 @@ do_stats(void)
        blocks = spcl.c_tapea - tapea_volume;
        msg("Volume %d completed at: %s", tapeno, ctime(&tnow));
        if (! compressed)
-               msg("Volume %d %ld tape blocks (%.2fMB)\n", tapeno, 
+               msg("Volume %d %ld blocks (%.2fMB)\n", tapeno, 
                        blocks, ((double)blocks * TP_BSIZE / 1048576));
        if (ttaken > 0) {
                long volkb = (bytes_written - tapea_bytes) / 1024;
@@ -411,9 +455,13 @@ flushtape(void)
 
        int siz = (char *)nextblock - (char *)slp->req;
 
+       /* make sure returned has sane values in case we don't read 
+        * them from the slave in this pass */
+       returned.unclen = returned.clen = writesize;
+
        slp->req[trecno].count = 0;                     /* Sentinel */
 
-       if (atomic_write( slp->fd, (char *)slp->req, siz) != siz)
+       if (dump_atomic_write( slp->fd, (char *)slp->req, siz) != siz)
                quit("error writing command pipe: %s\n", strerror(errno));
        slp->sent = 1; /* we sent a request, read the response later */
 
@@ -424,7 +472,7 @@ flushtape(void)
 
        /* Read results back from next slave */
        if (slp->sent) {
-               if (atomic_read( slp->fd, (char *)&returned, sizeof returned)
+               if (dump_atomic_read( slp->fd, (char *)&returned, sizeof returned)
                    != sizeof returned) {
                        perror("  DUMP: error reading command pipe in master");
                        dumpabort(0);
@@ -449,7 +497,7 @@ flushtape(void)
                         */
                        for (i = 0; i < SLAVES; i++) {
                                if (slaves[i].sent) {
-                                       if (atomic_read( slaves[i].fd,
+                                       if (dump_atomic_read( slaves[i].fd,
                                            (char *)&returned, sizeof returned)
                                            != sizeof returned) {
                                                perror("  DUMP: error reading command pipe in master");
@@ -466,10 +514,14 @@ flushtape(void)
        }
 
        blks = 0;
-       if (spcl.c_type != TS_END) {
-               for (i = 0; i < spcl.c_count; i++)
-                       if (spcl.c_addr[i] != 0)
-                               blks++;
+       if (spcl.c_type == TS_CLRI || spcl.c_type == TS_BITS)
+               blks = spcl.c_count;
+       else {
+               if (spcl.c_type != TS_END) {
+                       for (i = 0; i < spcl.c_count; i++)
+                               if (spcl.c_addr[i] != 0)
+                                       blks++;
+               }
        }
        slp->count = lastspclrec + blks + 1 - spcl.c_tapea;
        slp->tapea = spcl.c_tapea;
@@ -481,9 +533,9 @@ flushtape(void)
        blockswritten += ntrec;
        blocksthisvol += ntrec;
        if (!pipeout && !unlimited) {
-               if (blocksperfile) {
-                       if ( compressed ? (bytes_written - tapea_bytes + SLAVES * (writesize + sizeof(struct tapebuf))) >= blocksperfile * 1024
-                                       : blocksthisvol >= blocksperfile ) {
+               if (blocksperfiles && blocksperfiles[blocksperfiles_current]) {
+                       if ( compressed ? (bytes_written - tapea_bytes + SLAVES * (writesize + sizeof(struct tapebuf))) >= (((long long)blocksperfiles[blocksperfiles_current]) * 1024)
+                                       : blocksthisvol >= blocksperfiles[blocksperfiles_current] ) {
                                close_rewind();
                                startnewtape(0);
                        }
@@ -513,7 +565,7 @@ trewind(void)
                 * fixme: punt for now.
                 */
                if (slaves[f].sent) {
-                       if (atomic_read( slaves[f].fd, (char *)&returned, sizeof returned)
+                       if (dump_atomic_read( slaves[f].fd, (char *)&returned, sizeof returned)
                            != sizeof returned) {
                                perror("  DUMP: error reading command pipe in master");
                                dumpabort(0);
@@ -545,7 +597,7 @@ trewind(void)
 #ifdef RDUMP
                if (host) {
                        rmtclose();
-                       while (rmtopen(tape, 0) < 0)
+                       while (rmtopen(tape, O_RDONLY) < 0)
                                sleep(10);
                        rmtclose();
                }
@@ -554,20 +606,11 @@ trewind(void)
                {
                        (void) close(tapefd);
                        if (!fifoout) {
-                               while ((f = OPEN(tape, 0)) < 0)
+                               while ((f = OPEN(tape, O_RDONLY)) < 0)
                                        sleep (10);
                                (void) close(f);
                        }
                }
-               eot_code = 1;
-               if (eot_script && spcl.c_type != TS_END) {
-                       msg("Launching %s\n", eot_script);
-                       eot_code = system_command(eot_script, tape, tapeno);
-               }
-               if (eot_code != 0 && eot_code != 1) {
-                       msg("Dump aborted by the end of tape script\n");
-                       dumpabort(0);
-               }
        }
        return do_stats();
 }
@@ -576,8 +619,19 @@ trewind(void)
 void
 close_rewind(void)
 {
+       int eot_code = 1;
        (void)trewind();
-       if (nexttape || Mflag || (eot_code == 0) )
+       if (eot_script) {
+               msg("Launching %s\n", eot_script);
+               eot_code = system_command(eot_script, tape, tapeno);
+       }
+       if (eot_code != 0 && eot_code != 1) {
+               msg("Dump aborted by the end of tape script\n");
+               dumpabort(0);
+       }
+       if (eot_code == 0)
+               return;
+       if (nexttape || Mflag)
                return;
        if (!nogripe) {
                msg("Change Volumes: Mount volume #%d\n", tapeno+1);
@@ -593,8 +647,8 @@ close_rewind(void)
 void
 rollforward(void)
 {
-       register struct req *p, *q = NULL, *prev;
-       register struct slave *tslp;
+       struct req *p, *q = NULL, *prev;
+       struct slave *tslp;
        int i, size, savedtapea, got;
        union u_spcl *ntb, *otb;
        struct slave_results returned;
@@ -605,6 +659,10 @@ rollforward(void)
        tslp = &slaves[SLAVES];
        ntb = (union u_spcl *)tslp->tblock[1];
 
+       /* make sure returned has sane values in case we don't read 
+        * them from the slave in this pass */
+       returned.unclen = returned.clen = writesize;
+
        /*
         * Each of the N slaves should have requests that need to
         * be replayed on the next tape.  Use the extra slave buffers
@@ -648,7 +706,7 @@ rollforward(void)
                        lastspclrec = savedtapea - 1;
                }
                size = (char *)ntb - (char *)q;
-               if (atomic_write( slp->fd, (char *)q, size) != size) {
+               if (dump_atomic_write( slp->fd, (char *)q, size) != size) {
                        perror("  DUMP: error writing command pipe");
                        dumpabort(0);
                }
@@ -696,7 +754,7 @@ rollforward(void)
         * worked ok, otherwise the tape is much too short!
         */
        if (slp->sent) {
-               if (atomic_read( slp->fd, (char *)&returned, sizeof returned)
+               if (dump_atomic_read( slp->fd, (char *)&returned, sizeof returned)
                    != sizeof returned) {
                        perror("  DUMP: error reading command pipe in master");
                        dumpabort(0);
@@ -732,6 +790,16 @@ rollforward(void)
 #endif
 }
 
+#ifdef __linux__
+#if defined(SYS_clone) && defined(CLONE_IO)
+pid_t
+fork_clone_io(void)
+{
+       return syscall(SYS_clone, CLONE_ARGS);
+}
+#endif
+#endif
+
 /*
  * We implement taking and restoring checkpoints on the tape level.
  * When each tape is opened, a new process is created by forking; this
@@ -778,7 +846,7 @@ restore_check_point:
        /*
         *      All signals are inherited...
         */
-       childpid = fork();
+       childpid = fork_clone_io();
        if (childpid < 0) {
                msg("Context save fork fails in parent %d\n", parentpid);
                Exit(X_ABORT);
@@ -866,16 +934,19 @@ restore_check_point:
                        tape[MAXPATHLEN - 1] = '\0';
                        msg("Dumping volume %d on %s\n", tapeno, tape);
                }
+               if (blocksperfiles && blocksperfiles_current < *blocksperfiles)
+                       blocksperfiles_current++;
 #ifdef RDUMP
-               while ((tapefd = (host ? rmtopen(tape, 2) : pipeout ? 
+               while ((tapefd = (host ? rmtopen(tape, O_WRONLY|O_CREAT|O_TRUNC) : pipeout ? 
                        fileno(stdout) : 
-                       OPEN(tape, O_WRONLY|O_CREAT, 0666))) < 0)
+                       OPEN(tape, O_WRONLY|O_CREAT|O_TRUNC, 0666))) < 0)
 #else
                while ((tapefd = (pipeout ? fileno(stdout) :
-                                 OPEN(tape, O_RDWR|O_CREAT, 0666))) < 0)
+                                 OPEN(tape, O_WRONLY|O_CREAT|O_TRUNC, 0666))) < 0)
 #endif
                    {
-                       msg("Cannot open output \"%s\".\n", tape);
+                       msg("Cannot open output \"%s\": %s\n", tape, 
+                           strerror(errno));
                        if (!query("Do you want to retry the open?"))
                                dumpabort(0);
                }
@@ -916,13 +987,13 @@ restore_check_point:
                if (tapeno > 1)
                        msg("Volume %d begins with blocks from inode %d\n",
                                tapeno, slp->inode);
-               if (tapeno < TP_NINOS)
+               if (tapeno < (int)TP_NINOS)
                        volinfo[tapeno] = slp->inode;
        }
 }
 
 void
-dumpabort(int signo)
+dumpabort(UNUSED(int signo))
 {
 
        if (master != 0 && master != getpid())
@@ -952,7 +1023,7 @@ Exit(int status)
  * proceed - handler for SIGUSR2, used to synchronize IO between the slaves.
  */
 static void
-proceed(int signo)
+proceed(UNUSED(int signo))
 {
        if (ready)
                siglongjmp(jmpbuf, 1);
@@ -966,7 +1037,7 @@ enslave(void)
 #ifdef LINUX_FORK_BUG
        int i, j;
 #else
-       register int i, j;
+       int i, j;
 #endif
 
        master = getpid();
@@ -991,7 +1062,7 @@ enslave(void)
                }
 
                if (socketpair(AF_UNIX, SOCK_STREAM, 0, cmd) < 0 ||
-                   (slaves[i].pid = fork()) < 0)
+                   (slaves[i].pid = fork_clone_io()) < 0)
                        quit("too many slaves, %d (recompile smaller): %s\n",
                            i, strerror(errno));
 
@@ -1009,11 +1080,15 @@ enslave(void)
                        sigprocmask(SIG_BLOCK, &sigs, NULL);
 
 #ifdef LINUX_FORK_BUG
-                       if (atomic_write( cmd[0], (char *) &i, sizeof i)
+                       if (dump_atomic_write( cmd[0], (char *) &i, sizeof i)
                            != sizeof i)
                                quit("master/slave protocol botched 3\n");
 #endif
-                       doslave(cmd[0], i, (slaves[i].pid == slp->pid));
+                       doslave(cmd[0], 
+#ifdef WRITEDEBUG
+                               i, 
+#endif
+                               (slaves[i].pid == slp->pid));
                        Exit(X_FINOK);
                }
                else
@@ -1027,12 +1102,12 @@ enslave(void)
         * returned from fork() causes a SEGV in the child process
         */
        for (i = 0; i < SLAVES; i++)
-               if (atomic_read( slaves[i].fd, (char *) &j, sizeof j) != sizeof j)
+               if (dump_atomic_read( slaves[i].fd, (char *) &j, sizeof j) != sizeof j)
                        quit("master/slave protocol botched 4\n");
 #endif
 
        for (i = 0; i < SLAVES; i++)
-               (void) atomic_write( slaves[i].fd, 
+               (void) dump_atomic_write( slaves[i].fd, 
                              (char *) &slaves[(i + 1) % SLAVES].pid, 
                              sizeof slaves[0].pid);
                
@@ -1042,7 +1117,7 @@ enslave(void)
 void
 killall(void)
 {
-       register int i;
+       int i;
 
        for (i = 0; i < SLAVES; i++)
                if (slaves[i].pid > 0) {
@@ -1059,20 +1134,25 @@ killall(void)
  * slaves.
  */
 static void
-doslave(int cmd, int slave_number, int first)
+doslave(int cmd, 
+#ifdef WRITEDEBUG
+       int slave_number, 
+#endif
+       int first)
 {
-       register int nread;
-       int nextslave, size, eot_count, bufsize;
-       volatile int wrote = 0;
-       char *buffer;
-#if defined(HAVE_ZLIB) || defined(HAVE_BZLIB)
-       struct tapebuf *comp_buf = NULL;
-       int compresult, do_compress = !first;
+       int nread;
+       int nextslave;
+       volatile int wrote = 0, size, eot_count, bufsize;
+       char * volatile buffer;
+#if defined(HAVE_ZLIB) || defined(HAVE_BZLIB) || defined(HAVE_LZO)
+       struct tapebuf * volatile comp_buf = NULL;
+       int compresult;
+       volatile int do_compress = !first;
        unsigned long worklen;
-#ifdef HAVE_BZLIB
-       unsigned int worklen2;
+#ifdef HAVE_LZO
+       lzo_align_t __LZO_MMODEL *LZO_WorkMem;
 #endif
-#endif /* HAVE_ZLIB || HAVE_BZLIB */
+#endif /* HAVE_ZLIB || HAVE_BZLIB || HAVE_LZO */
        struct slave_results returns;
 #ifdef __linux__
        errcode_t retval;
@@ -1081,6 +1161,9 @@ doslave(int cmd, int slave_number, int first)
        long long curtapepos;
        union u_spcl *uspclptr;
        struct s_spcl *spclptr;
+       /* long         maxntrecs = 300000000 / (ntrec * 1024);  last tested: 50 000 000 */
+       long            maxntrecs = 50000;      /* every 50MB */
+       long            cntntrecs = maxntrecs;
 #endif /* USE_QFA */
        sigset_t set;
 
@@ -1097,7 +1180,7 @@ doslave(int cmd, int slave_number, int first)
                quit("slave couldn't reopen disk: %s\n", strerror(errno));
 #ifdef __linux__
 #ifdef BLKFLSBUF
-       (void)ioctl(diskfd, BLKFLSBUF);
+       (void)ioctl(diskfd, BLKFLSBUF, 0);
 #endif
        ext2fs_close(fs);
        retval = dump_fs_open(disk, &fs);
@@ -1108,29 +1191,45 @@ doslave(int cmd, int slave_number, int first)
        /*
         * Need the pid of the next slave in the loop...
         */
-       if ((nread = atomic_read( cmd, (char *)&nextslave, sizeof nextslave))
+       if ((nread = dump_atomic_read( cmd, (char *)&nextslave, sizeof nextslave))
            != sizeof nextslave) {
                quit("master/slave protocol botched - didn't get pid of next slave.\n");
        }
 
-#if defined(HAVE_ZLIB) || defined(HAVE_BZLIB)
+#if defined(HAVE_ZLIB) || defined(HAVE_BZLIB) || defined(HAVE_LZO)
        /* if we're doing a compressed dump, allocate the compress buffer */
        if (compressed) {
-               comp_buf = malloc(sizeof(struct tapebuf) + TP_BSIZE + writesize);
+               int bsiz = sizeof(struct tapebuf) + writesize;
+               /* Add extra space to deal with compression enlarging the buffer */
+               if (TP_BSIZE > writesize/16 + 67)
+                       bsiz += TP_BSIZE;
+               else
+                       bsiz += writesize/16 + 67;
+               comp_buf = malloc(bsiz);
                if (comp_buf == NULL)
                        quit("couldn't allocate a compress buffer.\n");
-               if (bzipflag)
-                       comp_buf->flags = COMPRESS_BZLIB;
-               else
+               if (zipflag == COMPRESS_ZLIB)
                        comp_buf->flags = COMPRESS_ZLIB;
+               else if (zipflag == COMPRESS_BZLIB)
+                       comp_buf->flags = COMPRESS_BZLIB;
+                else if (zipflag == COMPRESS_LZO) {
+                       comp_buf->flags = COMPRESS_LZO;
+                       if (lzo_init() != LZO_E_OK) quit("lzo_init failed\n");
+                } else 
+                       quit("internal error - unknown compression method: %d\n", zipflag);
        }
-#endif /* HAVE_ZLIB || HAVE_BZLIB */
+#ifdef HAVE_LZO
+       LZO_WorkMem = malloc(LZO1X_1_MEM_COMPRESS);
+       if (!LZO_WorkMem)
+               quit("couldn't allocate a compress buffer.\n");
+#endif
+#endif /* HAVE_ZLIB || HAVE_BZLIB || HAVE_LZO */
 
        /*
         * Get list of blocks to dump, read the blocks into tape buffer
         */
-       while ((nread = atomic_read( cmd, (char *)slp->req, reqsiz)) == reqsiz) {
-               register struct req *p = slp->req;
+       while ((nread = dump_atomic_read( cmd, (char *)slp->req, reqsiz)) == reqsiz) {
+               struct req *p = slp->req;
 
                for (trecno = 0; trecno < ntrec;
                     trecno += p->count, p += p->count) {
@@ -1138,7 +1237,7 @@ doslave(int cmd, int slave_number, int first)
                                bread(p->dblk, slp->tblock[trecno],
                                        p->count * TP_BSIZE);
                        } else {        /* read record from pipe */
-                               if (p->count != 1 || atomic_read( cmd,
+                               if (p->count != 1 || dump_atomic_read( cmd,
                                    (char *)slp->tblock[trecno],
                                    TP_BSIZE) != TP_BSIZE)
                                       quit("master/slave protocol botched.\n");
@@ -1153,7 +1252,7 @@ doslave(int cmd, int slave_number, int first)
                bufsize = writesize;                    /* length to write */
                returns.clen = returns.unclen = bufsize;
 
-#if defined(HAVE_ZLIB) || defined(HAVE_BZLIB)
+#if defined(HAVE_ZLIB) || defined(HAVE_BZLIB) || defined(HAVE_LZO)
                /* 
                 * When writing a compressed dump, each block except
                 * the first one on each tape is written
@@ -1172,7 +1271,7 @@ doslave(int cmd, int slave_number, int first)
                        worklen = TP_BSIZE + writesize;
                        compresult = 1;
 #ifdef HAVE_ZLIB
-                       if (!bzipflag) {
+                       if (zipflag == COMPRESS_ZLIB) {
                                compresult = compress2(comp_buf->buf, 
                                                       &worklen,
                                                       (char *)slp->tblock[0],
@@ -1185,8 +1284,8 @@ doslave(int cmd, int slave_number, int first)
                        }
 #endif /* HAVE_ZLIB */
 #ifdef HAVE_BZLIB
-                       if (bzipflag) {
-                               worklen2 = worklen;
+                       if (zipflag == COMPRESS_BZLIB) {
+                               unsigned int worklen2 = worklen;
                                compresult = BZ2_bzBuffToBuffCompress(
                                                       comp_buf->buf,
                                                       &worklen2,
@@ -1202,7 +1301,21 @@ doslave(int cmd, int slave_number, int first)
                        }
 
 #endif /* HAVE_BZLIB */
-                       if (compresult && worklen <= (writesize - 16)) {
+#ifdef HAVE_LZO
+                       if (zipflag == COMPRESS_LZO) {
+                               lzo_uint worklen2 = worklen;
+                               compresult = lzo1x_1_compress((char *)slp->tblock[0],writesize,
+                                                              comp_buf->buf,
+                                                             &worklen2,
+                                                              LZO_WorkMem);
+                               worklen = worklen2;
+                               if (compresult == LZO_E_OK)
+                                       compresult = 1;
+                               else
+                                       compresult = 0;
+                       }
+#endif /* HAVE_LZO */
+                       if (compresult && worklen <= ((unsigned long)writesize - 16)) {
                                /* write the compressed buffer */
                                comp_buf->length = worklen;
                                comp_buf->compressed = 1;
@@ -1221,7 +1334,7 @@ doslave(int cmd, int slave_number, int first)
                }
                /* compress the remaining blocks if we're compressing */
                do_compress = compressed;
-#endif /* HAVE_ZLIB  || HAVE_BZLIB */
+#endif /* HAVE_ZLIB  || HAVE_BZLIB || HAVE_LZO */
 
                if (sigsetjmp(jmpbuf, 1) == 0) {
                        ready = 1;
@@ -1234,18 +1347,31 @@ doslave(int cmd, int slave_number, int first)
 #ifdef USE_QFA
                if (gTapeposfd >= 0) {
                        int i;
-                       for (i = 0; i < ntrec; ++i) {
+                       int foundone = 0;
+
+                       for (i = 0; (i < ntrec) && !foundone; ++i) {
                                uspclptr = (union u_spcl *)&slp->tblock[i];
                                spclptr = &uspclptr->s_spcl;
                                if ((spclptr->c_magic == NFS_MAGIC) && 
-                                   (spclptr->c_type == TS_INODE) &&
-                                   (spclptr->c_date == gThisDumpDate)) {
-                                       /* if an error occured previously don't
-                                        * try again */
-                                       if (gtperr == 0) {
-                                               if ((gtperr = GetTapePos(&curtapepos)) == 0)
-                                                       MkTapeString(spclptr, curtapepos);
-                                       }
+                                                       (spclptr->c_type == TS_INODE) &&
+                                                       (spclptr->c_date == gThisDumpDate) &&
+                                                       !(spclptr->c_dinode.di_mode & S_IFDIR) &&
+                                                       !(spclptr->c_flags & DR_EXTATTRIBUTES)
+                                               ) {
+                                       foundone = 1;
+                                       /* if (cntntrecs >= maxntrecs) {         only write every maxntrecs amount of data */
+                                               cntntrecs = 0;
+                                               if (gtperr == 0) 
+                                                       gtperr = GetTapePos(&curtapepos);
+                                               /* if an error occured previously don't
+                                                * try again */
+                                               if (gtperr == 0) {
+#ifdef DEBUG_QFA
+                                                       msg("inode %ld at tapepos %ld\n", spclptr->c_inumber, curtapepos);
+#endif
+                                                       gtperr = MkTapeString(spclptr, curtapepos);
+                                               }
+                                       /* } */
                                }
                        }
                }
@@ -1261,11 +1387,12 @@ doslave(int cmd, int slave_number, int first)
 #ifdef WRITEDEBUG
                        printf("slave %d wrote %d\n", slave_number, wrote);
 #endif
-                       if (wrote < 0)
+                       if (wrote < 0 && errno != ENOSPC)
                                break;
-                       if (wrote == 0)
+                       if (wrote == 0 || (wrote < 0 && errno == ENOSPC))
                                eot_count++;
-                       size += wrote;
+                       else
+                               size += wrote;
                }
 
 #ifdef WRITEDEBUG
@@ -1295,12 +1422,17 @@ doslave(int cmd, int slave_number, int first)
                 * pass size of data and size of write back to master
                 * (for EOT handling)
                 */
-               (void) atomic_write( cmd, (char *)&returns, sizeof returns);
+               (void) dump_atomic_write( cmd, (char *)&returns, sizeof returns);
 
                /*
                 * Signal the next slave to go.
                 */
                (void) kill(nextslave, SIGUSR2);
+#ifdef USE_QFA
+               if (gTapeposfd >= 0) {
+                       cntntrecs += ntrec;
+               }
+#endif /* USE_QFA */
        }
        if (nread != 0)
                quit("error reading command pipe: %s\n", strerror(errno));
@@ -1312,15 +1444,15 @@ doslave(int cmd, int slave_number, int first)
  * loop until the count is satisfied (or error).
  */
 static ssize_t
-atomic_read(int fd, void *buf, size_t count)
+dump_atomic_read(int fd, char *buf, size_t count)
 {
        int got, need = count;
 
        do {
                while ((got = read(fd, buf, need)) > 0 && (need -= got) > 0)
-                       (char *)buf += got;
+                       buf += got;
        } while (got == -1 && errno == EINTR);
-       return (got < 0 ? got : count - need);
+       return (got < 0 ? got : (ssize_t)count - need);
 }
 
 /*
@@ -1329,19 +1461,39 @@ atomic_read(int fd, void *buf, size_t count)
  * loop until the count is satisfied (or error).
  */
 static ssize_t
-atomic_write(int fd, const void *buf, size_t count)
+dump_atomic_write(int fd, const char *buf, size_t count)
 {
        int got, need = count;
 
        do {
                while ((got = write(fd, buf, need)) > 0 && (need -= got) > 0)
-                       (char *)buf += got;
+                       buf += got;
        } while (got == -1 && errno == EINTR);
-       return (got < 0 ? got : count - need);
+       return (got < 0 ? got : (ssize_t)count - need);
 }
 
 
+/*
+int
+SetLogicalPos(void)
+{
+       int     err = 0;
+       struct mt_pos buf;
+
+       buf.mt_op = MTSETDRVBUFFER;
+       buf.mt_count = MT_ST_BOOLEANS | MT_ST_SCSI2LOGICAL;
+       if (ioctl(tapefd, MTIOCTOP, &buf) == -1) {
+               err = errno;
+               msg("[%ld] error: %d (setting logical)\n", 
+                       (unsigned long)getpid(), err);
+       }
+       return err;
+}
+*/
+
 #ifdef USE_QFA
+#define LSEEK_GET_TAPEPOS      10
+#define LSEEK_GO2_TAPEPOS      11
 /*
  * read the current tape position
  */
@@ -1352,7 +1504,7 @@ GetTapePos(long long *pos)
 
 #ifdef RDUMP
        if (host) {
-               *pos = (long long) rmtseek(0, SEEK_CUR);
+               *pos = (long long) rmtseek((OFF_T)0, (int)LSEEK_GET_TAPEPOS);
                err = *pos < 0;
        }
        else 
@@ -1378,8 +1530,10 @@ GetTapePos(long long *pos)
        return err;
 }
 
-static void 
-MkTapeString(struct s_spcl *spclptr, long long curtapepos) {
+static int 
+MkTapeString(struct s_spcl *spclptr, long long curtapepos)
+{
+       int     err = 0;
 
 #ifdef DEBUG_QFA
        msg("inode %ld at tapepos %lld\n", spclptr->c_inumber, curtapepos);
@@ -1390,8 +1544,10 @@ MkTapeString(struct s_spcl *spclptr, long long curtapepos) {
                 tapeno, 
                 curtapepos);
        gTps[sizeof(gTps) - 1] = '\0';
-       if (write(gTapeposfd, gTps, strlen(gTps)) != strlen(gTps)) {
-               warn("error writing tapepos file.\n");
+       if (write(gTapeposfd, gTps, strlen(gTps)) != (ssize_t)strlen(gTps)) {
+               err = errno;
+       warn("error writing tapepos file. (error %d)\n", errno);
        }
+       return err;
 }
 #endif /* USE_QFA */