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 if (mntbuf == NULL) { 70 perror("show_info"); 71 exit(EXIT_FAILURE); 72 } 73 74 mntsize = getfsstat(mntbuf, (long)mntbufsize, MNT_NOWAIT); 75 curmount = mntsize - 1; 76 77 asprintf(&trailstr, ":%05d", pfsid); 78 79 /* 80 * Iterate all the mounted points looking for the PFS passed to 81 * this function. 82 */ 83 while(curmount >= 0) { 84 /* 85 * We need to avoid that PFS belonging to other HAMMER 86 * filesystems are showed as mounted, so we compare 87 * against the FSID, which is presumable to be unique. 88 */ 89 bzero(&hi, sizeof(hi)); 90 if ((fd = open(mntbuf[curmount].f_mntfromname, O_RDONLY)) < 0) { 91 curmount--; 92 continue; 93 } 94 95 if ((ioctl(fd, HAMMERIOC_GET_INFO, &hi)) < 0) { 96 curmount--; 97 continue; 98 } 99 100 if (strstr(mntbuf[curmount].f_mntfromname, trailstr) != NULL && 101 (uuid_compare(&hi.vol_fsid, &parentuuid, NULL)) == 0) { 102 if (ismaster) { 103 if (strstr(mntbuf[curmount].f_mntfromname, 104 "@@-1") != NULL) { 105 retval = 106 strdup(mntbuf[curmount].f_mntonname); 107 break; 108 } 109 } else { 110 if (strstr(mntbuf[curmount].f_mntfromname, 111 "@@0x") != NULL ) { 112 retval = 113 strdup(mntbuf[curmount].f_mntonname); 114 break; 115 } 116 } 117 } 118 curmount--; 119 close(fd); 120 } 121 free(trailstr); 122 123 return retval; 124 } 125 126 /* 127 * Allocate len bytes of memory and return the pointer. 128 * It'll exit in the case no memory could be allocated. 129 * 130 * To be used only by the library itself. 131 */ 132 void * 133 _libhammer_malloc(size_t len) 134 { 135 void *m; 136 137 m = calloc(len, sizeof(char)); 138 if (m == NULL) 139 errx(1, "Failed to allocate %zd bytes", len); 140 141 return (m); 142 } 143