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(uuid_t *unique_uuid) 50 { 51 struct hammer_ioc_pseudofs_rw pfs; 52 struct hammer_pseudofs_data pfsd; 53 struct statfs *mntbuf; 54 int mntsize; 55 int curmount; 56 int fd; 57 size_t mntbufsize; 58 uuid_t uuid; 59 char *retval; 60 61 retval = NULL; 62 63 /* Do not continue if there are no mounted filesystems */ 64 mntsize = getfsstat(NULL, 0, MNT_NOWAIT); 65 if (mntsize <= 0) 66 return retval; 67 68 mntbufsize = mntsize * sizeof(struct statfs); 69 mntbuf = _libhammer_malloc(mntbufsize); 70 71 mntsize = getfsstat(mntbuf, (long)mntbufsize, MNT_NOWAIT); 72 curmount = mntsize - 1; 73 74 /* 75 * Iterate all the mounted points looking for the PFS passed to 76 * this function. 77 */ 78 while(curmount >= 0) { 79 struct statfs *mnt = &mntbuf[curmount]; 80 /* 81 * Discard any non null(5) or hammer(5) filesystems as synthetic 82 * filesystems like procfs(5) could accept ioctl calls and thus 83 * produce bogus results. 84 */ 85 if ((strcmp("hammer", mnt->f_fstypename) != 0) && 86 (strcmp("null", mnt->f_fstypename) != 0)) { 87 curmount--; 88 continue; 89 } 90 bzero(&pfs, sizeof(pfs)); 91 bzero(&pfsd, sizeof(pfsd)); 92 pfs.pfs_id = -1; 93 pfs.ondisk = &pfsd; 94 pfs.bytes = sizeof(struct hammer_pseudofs_data); 95 fd = open(mnt->f_mntonname, O_RDONLY); 96 if (fd < 0 || (ioctl(fd, HAMMERIOC_GET_PSEUDOFS, &pfs) < 0)) { 97 close(fd); 98 curmount--; 99 continue; 100 } 101 102 memcpy(&uuid, &pfs.ondisk->unique_uuid, sizeof(uuid)); 103 if (uuid_compare(unique_uuid, &uuid, NULL) == 0) { 104 retval = strdup(mnt->f_mntonname); 105 close(fd); 106 break; 107 } 108 109 curmount--; 110 close(fd); 111 } 112 free(mntbuf); 113 114 return retval; 115 } 116 117 /* 118 * Allocate len bytes of memory and return the pointer. 119 * It'll exit in the case no memory could be allocated. 120 * 121 * To be used only by the library itself. 122 */ 123 void * 124 _libhammer_malloc(size_t len) 125 { 126 void *m; 127 128 m = calloc(len, sizeof(char)); 129 if (m == NULL) 130 errx(1, "Failed to allocate %zd bytes", len); 131 132 return (m); 133 } 134