1 /* 2 * Copyright (c) 2011 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * by Antonio Huete <tuxillo@quantumachine.net> 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in 16 * the documentation and/or other materials provided with the 17 * distribution. 18 * 3. Neither the name of The DragonFly Project nor the names of its 19 * contributors may be used to endorse or promote products derived 20 * from this software without specific, prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 #include <fcntl.h> 36 #include <err.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 41 #include <sys/mount.h> 42 #include <sys/stat.h> 43 #include <unistd.h> 44 #include <uuid.h> 45 46 #include "libhammer.h" 47 48 char * 49 libhammer_find_pfs_mount(int pfsid, uuid_t parentuuid, int ismaster) 50 { 51 struct hammer_ioc_info hi; 52 struct statfs *mntbuf; 53 int mntsize; 54 int curmount; 55 int fd; 56 size_t mntbufsize; 57 char *trailstr; 58 char *retval; 59 60 retval = NULL; 61 62 /* Do not continue if there are no mounted filesystems */ 63 mntsize = getfsstat(NULL, 0, MNT_NOWAIT); 64 if (mntsize <= 0) 65 return retval; 66 67 mntbufsize = mntsize * sizeof(struct statfs); 68 mntbuf = _libhammer_malloc(mntbufsize); 69 70 mntsize = getfsstat(mntbuf, (long)mntbufsize, MNT_NOWAIT); 71 curmount = mntsize - 1; 72 73 asprintf(&trailstr, ":%05d", pfsid); 74 75 /* 76 * Iterate all the mounted points looking for the PFS passed to 77 * this function. 78 */ 79 while(curmount >= 0) { 80 struct statfs *mnt = &mntbuf[curmount]; 81 /* 82 * We need to avoid that PFS belonging to other HAMMER 83 * filesystems are showed as mounted, so we compare 84 * against the FSID, which is presumable to be unique. 85 */ 86 bzero(&hi, sizeof(hi)); 87 if ((fd = open(mnt->f_mntfromname, O_RDONLY)) < 0) { 88 curmount--; 89 continue; 90 } 91 92 if (ioctl(fd, HAMMERIOC_GET_INFO, &hi) < 0) { 93 close(fd); 94 curmount--; 95 continue; 96 } 97 98 if (strstr(mnt->f_mntfromname, trailstr) != NULL && 99 (uuid_compare(&hi.vol_fsid, &parentuuid, NULL)) == 0) { 100 if (ismaster) { 101 if (strstr(mnt->f_mntfromname, 102 "@@-1") != NULL) { 103 retval = strdup(mnt->f_mntonname); 104 break; 105 } 106 } else { 107 if (strstr(mnt->f_mntfromname, 108 "@@0x") != NULL ) { 109 retval = strdup(mnt->f_mntonname); 110 break; 111 } 112 } 113 } 114 curmount--; 115 close(fd); 116 } 117 free(trailstr); 118 free(mntbuf); 119 120 return retval; 121 } 122 123 /* 124 * Allocate len bytes of memory and return the pointer. 125 * It'll exit in the case no memory could be allocated. 126 * 127 * To be used only by the library itself. 128 */ 129 void * 130 _libhammer_malloc(size_t len) 131 { 132 void *m; 133 134 m = calloc(len, sizeof(char)); 135 if (m == NULL) 136 errx(1, "Failed to allocate %zd bytes", len); 137 138 return (m); 139 } 140