X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lib%2Fext2fs%2Fismounted.c;h=eda04a3cfcc69679e847994b9950a0f465613307;hb=9005fe72d5619987593ec7ce52065dca9c11cf1c;hp=a65778e79aefd99ae7b5725c24e740d3e4d55a0d;hpb=c4e749abd8451f02418fe552b2af14f226f7bd1e;p=tools%2Fe2fsprogs.git

diff --git a/lib/ext2fs/ismounted.c b/lib/ext2fs/ismounted.c
index a65778e..eda04a3 100644
--- a/lib/ext2fs/ismounted.c
+++ b/lib/ext2fs/ismounted.c
@@ -1,14 +1,23 @@
 /*
  * ismounted.c --- Check to see if the filesystem was mounted
- * 
- * Copyright (C) 1995 Theodore Ts'o.
+ *
+ * Copyright (C) 1995,1996,1997,1998,1999,2000 Theodore Ts'o.
  *
  * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
  * %End-Header%
  */
 
+/* define BSD_SOURCE to make sure we get the major() macro */
+#ifndef _BSD_SOURCE
+#define _BSD_SOURCE
+#endif
+#ifndef _DEFAULT_SOURCE
+#define _DEFAULT_SOURCE	/* since glibc 2.20 _SVID_SOURCE is deprecated */
+#endif
+
+#include "config.h"
 #include <stdio.h>
 #if HAVE_UNISTD_H
 #include <unistd.h>
@@ -17,12 +26,16 @@
 #include <errno.h>
 #endif
 #include <fcntl.h>
-#ifdef HAVE_LINUX_FS_H
-#include <linux/fs.h>
-#endif
 #ifdef HAVE_LINUX_FD_H
 #include <linux/fd.h>
 #endif
+#ifdef HAVE_LINUX_LOOP_H
+#include <linux/loop.h>
+#include <sys/ioctl.h>
+#ifdef HAVE_LINUX_MAJOR_H
+#include <linux/major.h>
+#endif /* HAVE_LINUX_MAJOR_H */
+#endif /* HAVE_LINUX_LOOP_H */
 #ifdef HAVE_MNTENT_H
 #include <mntent.h>
 #endif
@@ -31,52 +44,222 @@
 #include <sys/param.h>
 #include <sys/mount.h>
 #endif /* HAVE_GETMNTINFO */
-
-#if EXT2_FLAT_INCLUDES
-#include "ext2_fs.h"
-#else
-#include <linux/ext2_fs.h>
+#include <string.h>
+#include <sys/stat.h>
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
 #endif
+#ifdef HAVE_SYS_SYSMACROS_H
+#include <sys/sysmacros.h>
+#endif
+#include <dirent.h>
 
+#include "ext2_fs.h"
 #include "ext2fs.h"
+#include "ext2fsP.h"
+
+#ifdef HAVE_SETMNTENT
+/*
+ * Check to see if a regular file is mounted.
+ * If /etc/mtab/ is a symlink of /proc/mounts, you will need the following check
+ * because the name in /proc/mounts is a loopback device not a regular file.
+ */
+static int check_loop_mounted(const char *mnt_fsname, dev_t mnt_rdev,
+				dev_t file_dev, ino_t file_ino)
+{
+#if defined(HAVE_LINUX_LOOP_H) && defined(HAVE_LINUX_MAJOR_H)
+	struct loop_info64 loopinfo = {0, };
+	int loop_fd, ret;
+
+	if (major(mnt_rdev) == LOOP_MAJOR) {
+		loop_fd = open(mnt_fsname, O_RDONLY);
+		if (loop_fd < 0)
+			return -1;
+
+		ret = ioctl(loop_fd, LOOP_GET_STATUS64, &loopinfo);
+		close(loop_fd);
+		if (ret < 0)
+			return -1;
+
+		if (file_dev == loopinfo.lo_device &&
+				file_ino == loopinfo.lo_inode)
+			return 1;
+	}
+#endif /* defined(HAVE_LINUX_LOOP_H) && defined(HAVE_LINUX_MAJOR_H) */
+	return 0;
+}
 
-#ifdef HAVE_MNTENT_H
 /*
- * XXX we only check to see if the mount is readonly when it's the
- * root filesystem.
+ * Helper function which checks a file in /etc/mtab format to see if a
+ * filesystem is mounted.  Returns an error if the file doesn't exist
+ * or can't be opened.
  */
-static errcode_t check_mntent(const char *file, int *mount_flags)
+static errcode_t check_mntent_file(const char *mtab_file, const char *file,
+				   int *mount_flags, char *mtpt, int mtlen)
 {
-	FILE * f;
-	struct mntent * mnt;
-	int	fd;
+	struct mntent 	*mnt;
+	struct stat	st_buf, dir_st_buf;
+	errcode_t	retval = 0;
+	dev_t		file_dev=0, file_rdev=0;
+	ino_t		file_ino=0;
+	FILE 		*f;
+	int		fd;
 
 	*mount_flags = 0;
-	if ((f = setmntent (MOUNTED, "r")) == NULL)
+
+	if ((f = setmntent (mtab_file, "r")) == NULL) {
+		if (errno == ENOENT) {
+			if (getenv("EXT2FS_NO_MTAB_OK"))
+				return 0;
+			else
+				return EXT2_ET_NO_MTAB_FILE;
+		}
 		return errno;
-	while ((mnt = getmntent (f)) != NULL)
-		if (strcmp(file, mnt->mnt_fsname) == 0)
+	}
+	if (stat(file, &st_buf) == 0) {
+		if (ext2fsP_is_disk_device(st_buf.st_mode)) {
+#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
+			file_rdev = st_buf.st_rdev;
+#endif	/* __GNU__ */
+		} else {
+			file_dev = st_buf.st_dev;
+			file_ino = st_buf.st_ino;
+		}
+	}
+	while ((mnt = getmntent (f)) != NULL) {
+		if (mnt->mnt_fsname[0] != '/')
+			continue;
+		if (strcmp(file, mnt->mnt_fsname) == 0) {
+			if (stat(mnt->mnt_dir, &st_buf) != 0)
+				continue;
+			if (file_rdev && (file_rdev != st_buf.st_dev)) {
+#ifdef DEBUG
+				printf("Bogus entry in %s!  "
+				       "(%s is not mounted on %s)\n",
+				       mtab_file, file, mnt->mnt_dir);
+#endif /* DEBUG */
+				continue;
+			}
 			break;
-	endmntent (f);
-	if (mnt == 0)
-		return 0;
+		}
+		if (stat(mnt->mnt_fsname, &st_buf) == 0) {
+			if (ext2fsP_is_disk_device(st_buf.st_mode)) {
+#ifndef __GNU__
+				if (file_rdev &&
+				    (file_rdev == st_buf.st_rdev)) {
+					if (stat(mnt->mnt_dir,
+						 &dir_st_buf) != 0)
+						continue;
+					if (file_rdev == dir_st_buf.st_dev)
+						break;
+				}
+				if (check_loop_mounted(mnt->mnt_fsname,
+						st_buf.st_rdev, file_dev,
+						file_ino) == 1)
+					break;
+#endif	/* __GNU__ */
+			} else {
+				if (file_dev && ((file_dev == st_buf.st_dev) &&
+						 (file_ino == st_buf.st_ino)))
+					break;
+			}
+		}
+	}
+
+	if (mnt == 0) {
+#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
+		/*
+		 * Do an extra check to see if this is the root device.  We
+		 * can't trust /etc/mtab, and /proc/mounts will only list
+		 * /dev/root for the root filesystem.  Argh.  Instead we
+		 * check if the given device has the same major/minor number
+		 * as the device that the root directory is on.
+		 */
+		if (file_rdev && stat("/", &st_buf) == 0) {
+			if (st_buf.st_dev == file_rdev) {
+				*mount_flags = EXT2_MF_MOUNTED;
+				if (mtpt)
+					strncpy(mtpt, "/", mtlen);
+				goto is_root;
+			}
+		}
+#endif	/* __GNU__ */
+		goto errout;
+	}
 	*mount_flags = EXT2_MF_MOUNTED;
-	
+
+#ifdef MNTOPT_RO
+	/* Check to see if the ro option is set */
+	if (hasmntopt(mnt, MNTOPT_RO))
+		*mount_flags |= EXT2_MF_READONLY;
+#endif
+
+	if (mtpt)
+		strncpy(mtpt, mnt->mnt_dir, mtlen);
+	/*
+	 * Check to see if we're referring to the root filesystem.
+	 * If so, do a manual check to see if we can open /etc/mtab
+	 * read/write, since if the root is mounted read/only, the
+	 * contents of /etc/mtab may not be accurate.
+	 */
 	if (!strcmp(mnt->mnt_dir, "/")) {
+is_root:
+#define TEST_FILE "/.ismount-test-file"
 		*mount_flags |= EXT2_MF_ISROOT;
-		fd = open(MOUNTED, O_RDWR);
+		fd = open(TEST_FILE, O_RDWR|O_CREAT, 0600);
 		if (fd < 0) {
 			if (errno == EROFS)
 				*mount_flags |= EXT2_MF_READONLY;
 		} else
 			close(fd);
+		(void) unlink(TEST_FILE);
 	}
+
+	if (mnt && mnt->mnt_type &&
+	    (!strcmp(mnt->mnt_type, "ext4") ||
+	     !strcmp(mnt->mnt_type, "ext3") ||
+	     !strcmp(mnt->mnt_type, "ext2")))
+		*mount_flags |= EXT2_MF_EXTFS;
+	retval = 0;
+errout:
+	endmntent (f);
+	return retval;
+}
+
+static errcode_t check_mntent(const char *file, int *mount_flags,
+			      char *mtpt, int mtlen)
+{
+	errcode_t	retval;
+
+#ifdef DEBUG
+	retval = check_mntent_file("/tmp/mtab", file, mount_flags,
+				   mtpt, mtlen);
+	if (retval == 0)
+		return 0;
+#endif /* DEBUG */
+#ifdef __linux__
+	retval = check_mntent_file("/proc/mounts", file, mount_flags,
+				   mtpt, mtlen);
+	if (retval == 0)
+		return 0;
+#endif /* __linux__ */
+#if defined(MOUNTED) || defined(_PATH_MOUNTED)
+#ifndef MOUNTED
+#define MOUNTED _PATH_MOUNTED
+#endif /* MOUNTED */
+	retval = check_mntent_file(MOUNTED, file, mount_flags, mtpt, mtlen);
+	return retval;
+#else
+	*mount_flags = 0;
 	return 0;
+#endif /* defined(MOUNTED) || defined(_PATH_MOUNTED) */
 }
-#endif
 
-#ifdef HAVE_GETMNTINFO
-static errcode_t check_getmntinfo(const char *file, int *mount_flags)
+#else
+#if defined(HAVE_GETMNTINFO)
+
+static errcode_t check_getmntinfo(const char *file, int *mount_flags,
+				  char *mtpt, int mtlen)
 {
 	struct statfs *mp;
         int    len, n;
@@ -91,7 +274,7 @@ static errcode_t check_getmntinfo(const char *file, int *mount_flags)
         s1 = file;
         if (strncmp(_PATH_DEV, s1, len) == 0)
                 s1 += len;
- 
+
 	*mount_flags = 0;
         while (--n >= 0) {
                 s2 = mp->f_mntfromname;
@@ -105,26 +288,385 @@ static errcode_t check_getmntinfo(const char *file, int *mount_flags)
 		}
                 ++mp;
 	}
+	if (mtpt)
+		strncpy(mtpt, mp->f_mntonname, mtlen);
 	return 0;
 }
 #endif /* HAVE_GETMNTINFO */
+#endif /* HAVE_SETMNTENT */
+
+/*
+ * Check to see if we're dealing with the swap device.
+ */
+static int is_swap_device(const char *file)
+{
+	FILE		*f;
+	char		buf[1024], *cp;
+	dev_t		file_dev;
+	struct stat	st_buf;
+	int		ret = 0;
+
+	file_dev = 0;
+#ifndef __GNU__ /* The GNU hurd is broken with respect to stat devices */
+	if ((stat(file, &st_buf) == 0) &&
+	    ext2fsP_is_disk_device(st_buf.st_mode))
+		file_dev = st_buf.st_rdev;
+#endif	/* __GNU__ */
+
+	if (!(f = fopen("/proc/swaps", "r")))
+		return 0;
+	/* Skip the first line */
+	if (!fgets(buf, sizeof(buf), f))
+		goto leave;
+	if (*buf && strncmp(buf, "Filename\t", 9))
+		/* Linux <=2.6.19 contained a bug in the /proc/swaps
+		 * code where the header would not be displayed
+		 */
+		goto valid_first_line;
+
+	while (fgets(buf, sizeof(buf), f)) {
+valid_first_line:
+		if ((cp = strchr(buf, ' ')) != NULL)
+			*cp = 0;
+		if ((cp = strchr(buf, '\t')) != NULL)
+			*cp = 0;
+		if (strcmp(buf, file) == 0) {
+			ret++;
+			break;
+		}
+#ifndef __GNU__
+		if (file_dev && (stat(buf, &st_buf) == 0) &&
+		    ext2fsP_is_disk_device(st_buf.st_mode) &&
+		    file_dev == st_buf.st_rdev) {
+			ret++;
+			break;
+		}
+#endif 	/* __GNU__ */
+	}
+
+leave:
+	fclose(f);
+	return ret;
+}
+
+static int check_lustre_zfs(char *mnt_device, const char *real_devname)
+{
+	char *real_mnt_device, *buf, *ptr;
+	FILE *fp;
+	int rc = 0;
+
+	real_mnt_device = malloc(PATH_MAX);
+	if (real_mnt_device == NULL) {
+		fprintf(stderr, "Cannot allocate memory to store path\n");
+		return 1;
+	}
+
+	buf = malloc(PATH_MAX);
+	if (buf == NULL) {
+		fprintf(stderr, "Cannot allocate memory to store command\n");
+		free(real_mnt_device);
+		return 1;
+	}
+
+	/* Get the pool name from mnt_device */
+	ptr = strchr(mnt_device, '/');
+	if (ptr)
+		*ptr = '\0';
+
+	memset(buf, 0, PATH_MAX);
+	sprintf(buf, "zpool list -Hv %s", mnt_device);
+
+	fp = popen(buf, "r");
+	if (fp) {
+		int line = 0;
+		while (!feof(fp)) {
+			memset(buf, 0, PATH_MAX);
+			if (fscanf(fp, "%s%*[^\n]", buf) < 1)
+				break;
+			/* skip the first line */
+			if (line++ == 0)
+				continue;
+			/* skip empty line */
+			if (strlen(buf) == 0)
+				continue;
+
+			if (realpath(buf, real_mnt_device) == NULL)
+				continue;
+			if (strcmp(real_devname, real_mnt_device) == 0) {
+				fprintf(stderr, "device %s mounted by Lustre\n",
+					real_devname);
+				rc = -1;
+				break;
+			}
+		}
+		pclose(fp);
+	}
+
+	return rc;
+}
+
+static int check_lustre_ldiskfs(const char *mnt_device,
+				const char *real_devname)
+{
+	char *real_mnt_device;
+
+	real_mnt_device = malloc(PATH_MAX);
+	if (real_mnt_device == NULL) {
+		fprintf(stderr, "Cannot allocate memory to store path\n");
+		return 1;
+	}
+
+	memset(real_mnt_device, 0, PATH_MAX);
+	if (realpath(mnt_device, real_mnt_device) == NULL) {
+		fprintf(stderr, "Cannot resolve mntdev %s\n", mnt_device);
+		free(real_mnt_device);
+		return 1;
+	}
+
+	if (strcmp(real_devname, real_mnt_device) == 0) {
+		fprintf(stderr, "device %s mounted by lustre\n", real_devname);
+		free(real_mnt_device);
+		return -1;
+	}
+
+	free(real_mnt_device);
+	return 0;
+}
+
+static int check_lustre_proc_vals(const char *procname,const char *real_devname)
+{
+	struct dirent *direntp;
+	DIR *dirp;
+	int rc = 0;
+	char  *mnt_device, *proc_val;
+
+	mnt_device = malloc(PATH_MAX);
+	if (mnt_device == NULL) {
+		fprintf(stderr, "Cannot allocate memory to store device\n");
+		return 1;
+	}
+	proc_val = malloc(PATH_MAX);
+	if (proc_val == NULL) {
+		fprintf(stderr, "Cannot allocate memory to store proc\n");
+		free(mnt_device);
+		return 1;
+	}
+
+	dirp = opendir(procname);
+	if (dirp) {
+		do {
+			int fd, numr;
+			char *ptr;
+
+			direntp = readdir(dirp);
+			if (direntp == NULL)
+				break;
+			if ((strncmp(direntp->d_name, ".", 1) == 0) ||
+			    (strncmp(direntp->d_name, "..", 2) == 0)) {
+				continue;
+			}
+
+			memset(proc_val, 0, PATH_MAX);
+			snprintf(proc_val, PATH_MAX, "%s/%s/mntdev", procname,
+				 direntp->d_name);
+			fd = open(proc_val, O_RDONLY);
+			if (fd < 0)  {
+				if (errno == ENOENT || errno == ENOTDIR)
+					continue;
+				fprintf(stderr, "Cannot open %s: %s\n",
+					proc_val, strerror(errno));
+				rc = 1;
+				break;
+			}
+
+			memset(mnt_device, 0, PATH_MAX);
+			numr = read(fd, mnt_device, PATH_MAX);
+			if (numr < 0) {
+				fprintf(stderr, "Failure to get mntdev info\n");
+				rc = 1;
+				close(fd);
+				break;
+			}
+			close(fd);
+
+			ptr = strchr(mnt_device, '\n');
+			if (ptr)
+				*ptr = '\0';
+
+			if (strstr(procname, "osd-zfs") != NULL)
+				rc = check_lustre_zfs(mnt_device, real_devname);
+			else
+				rc = check_lustre_ldiskfs(mnt_device,
+							  real_devname);
+
+		} while (direntp != NULL && rc == 0);
+
+		closedir(dirp);
+	}
+
+	free(proc_val);
+	free(mnt_device);
+
+	return rc;
+}
+
+static errcode_t check_if_lustre_mounted(const char *device, int *mount_flags)
+{
+	char *real_device;
+	int rc = 0;
+
+	real_device = malloc(PATH_MAX);
+	if (real_device == NULL) {
+		fprintf(stderr, "Cannot allocate memory to store path\n");
+		return EXT2_ET_NO_MEMORY;
+	}
+
+	if (realpath(device, real_device) == NULL) {
+		fprintf(stderr, "Cannot resolve path %s\n", device);
+		rc = EXT2_ET_BAD_DEVICE_NAME;
+		goto out_free;
+	}
+
+	rc = check_lustre_proc_vals("/proc/fs/lustre/osd-ldiskfs", real_device);
+	if (!rc)
+		rc = check_lustre_proc_vals("/proc/fs/lustre/osd-zfs",
+					    real_device);
+	if (rc)
+		*mount_flags |= EXT2_MF_MOUNTED;
+
+out_free:
+	free(real_device);
+
+	return rc;
+}
+
 
 /*
- * Is_mounted is set to 1 if the device is mounted, 0 otherwise
+ * ext2fs_check_mount_point() fills determines if the device is
+ * mounted or otherwise busy, and fills in mount_flags with one or
+ * more of the following flags: EXT2_MF_MOUNTED, EXT2_MF_ISROOT,
+ * EXT2_MF_READONLY, EXT2_MF_SWAP, and EXT2_MF_BUSY.  If mtpt is
+ * non-NULL, the directory where the device is mounted is copied to
+ * where mtpt is pointing, up to mtlen characters.
  */
 #ifdef __TURBOC__
-#pragma argsused
+ #pragma argsused
 #endif
-errcode_t ext2fs_check_if_mounted(const char *file, int *mount_flags)
+errcode_t ext2fs_check_mount_point(const char *device, int *mount_flags,
+				  char *mtpt, int mtlen)
 {
-#ifdef HAVE_MNTENT_H
-	return check_mntent(file, mount_flags);
-#else 
+	errcode_t	retval = 0;
+	int 		busy = 0;
+
+	if (getenv("EXT2FS_PRETEND_RO_MOUNT")) {
+		*mount_flags = EXT2_MF_MOUNTED | EXT2_MF_READONLY;
+		if (getenv("EXT2FS_PRETEND_ROOTFS"))
+			*mount_flags = EXT2_MF_ISROOT;
+		return 0;
+	}
+	if (getenv("EXT2FS_PRETEND_RW_MOUNT")) {
+		*mount_flags = EXT2_MF_MOUNTED;
+		if (getenv("EXT2FS_PRETEND_ROOTFS"))
+			*mount_flags = EXT2_MF_ISROOT;
+		return 0;
+	}
+
+#ifdef __linux__ /* This only works on Linux 2.6+ systems */
+	{
+		struct stat st_buf;
+
+		if (stat(device, &st_buf) == 0 &&
+		    ext2fsP_is_disk_device(st_buf.st_mode)) {
+			int fd = open(device, O_RDONLY | O_EXCL);
+
+			if (fd >= 0) {
+				/*
+				 * The device is not busy so it's
+				 * definitelly not mounted. No need to
+				 * to perform any more checks.
+				 */
+				close(fd);
+				*mount_flags = 0;
+				return 0;
+			} else if (errno == EBUSY) {
+				busy = 1;
+			}
+		}
+	}
+#endif
+
+	if (is_swap_device(device)) {
+		*mount_flags = EXT2_MF_MOUNTED | EXT2_MF_SWAP;
+		if (mtpt)
+			strncpy(mtpt, "<swap>", mtlen);
+	} else {
+#ifdef HAVE_SETMNTENT
+		retval = check_mntent(device, mount_flags, mtpt, mtlen);
+#else
 #ifdef HAVE_GETMNTINFO
-	return check_getmntinfo(file, mount_flags);
+		retval = check_getmntinfo(device, mount_flags, mtpt, mtlen);
 #else
-	*mount_flags = 0;
-	return 0;
+#if defined(__GNUC__) && !defined(_WIN32)
+ #warning "Can't use getmntent or getmntinfo to check for mounted filesystems!"
+#endif
+		*mount_flags = 0;
 #endif /* HAVE_GETMNTINFO */
-#endif /* HAVE_MNTENT_H */
+#endif /* HAVE_SETMNTENT */
+	}
+	if (retval)
+		return retval;
+
+	if (busy)
+		*mount_flags |= EXT2_MF_BUSY;
+
+	retval = check_if_lustre_mounted(device, mount_flags);
+
+	return 0;
+}
+
+/*
+ * ext2fs_check_if_mounted() sets the mount_flags EXT2_MF_MOUNTED,
+ * EXT2_MF_READONLY, and EXT2_MF_ROOT
+ *
+ */
+errcode_t ext2fs_check_if_mounted(const char *file, int *mount_flags)
+{
+	return ext2fs_check_mount_point(file, mount_flags, NULL, 0);
+}
+
+#ifdef DEBUG
+int main(int argc, char **argv)
+{
+	int	retval, mount_flags;
+	char	mntpt[80];
+
+	if (argc < 2) {
+		fprintf(stderr, "Usage: %s device\n", argv[0]);
+		exit(1);
+	}
+
+	add_error_table(&et_ext2_error_table);
+	mntpt[0] = 0;
+	retval = ext2fs_check_mount_point(argv[1], &mount_flags,
+					  mntpt, sizeof(mntpt));
+	if (retval) {
+		com_err(argv[0], retval,
+			"while calling ext2fs_check_if_mounted");
+		exit(1);
+	}
+	printf("Device %s reports flags %02x\n", argv[1], mount_flags);
+	if (mount_flags & EXT2_MF_BUSY)
+		printf("\t%s is apparently in use.\n", argv[1]);
+	if (mount_flags & EXT2_MF_MOUNTED)
+		printf("\t%s is mounted.\n", argv[1]);
+	if (mount_flags & EXT2_MF_SWAP)
+		printf("\t%s is a swap device.\n", argv[1]);
+	if (mount_flags & EXT2_MF_READONLY)
+		printf("\t%s is read-only.\n", argv[1]);
+	if (mount_flags & EXT2_MF_ISROOT)
+		printf("\t%s is the root filesystem.\n", argv[1]);
+	if (mntpt[0])
+		printf("\t%s is mounted on %s.\n", argv[1], mntpt);
+	exit(0);
 }
+#endif /* DEBUG */