Merge branch 'upstream' into tizen

[platform/upstream/cryptsetup.git] / lib / utils_loop.c

diff --git a/lib/utils_loop.c b/lib/utils_loop.c
index 640d95b..681c123 100644 (file)
--- a/lib/utils_loop.c
+++ b/lib/utils_loop.c
@@ -1,8 +1,8 @@
 /*
  * loopback block device utilities
  *
- * Copyright (C) 2011-2012, Red Hat, Inc. All rights reserved.
- * Copyright (C) 2009-2012, Milan Broz
+ * Copyright (C) 2009-2020 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2009-2020 Milan Broz
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -19,6 +19,7 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 #include <unistd.h>
@@ -28,6 +29,9 @@
 #include <sys/ioctl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
+#ifdef HAVE_SYS_SYSMACROS_H
+# include <sys/sysmacros.h>     /* for major, minor */
+#endif
 #include <linux/loop.h>
 #ifdef HAVE_SYS_SYSMACROS_H
 #include <sys/sysmacros.h>     /* for major, minor */
@@ -45,6 +49,10 @@
 #define LOOP_CTL_GET_FREE 0x4C82
 #endif
 
+#ifndef LOOP_SET_CAPACITY
+#define LOOP_SET_CAPACITY 0x4C07
+#endif
+
 static char *crypt_loop_get_device_old(void)
 {
        char dev[20];
@@ -69,7 +77,7 @@ static char *crypt_loop_get_device_old(void)
        return NULL;
 }
 
-char *crypt_loop_get_device(void)
+static char *crypt_loop_get_device(void)
 {
        char dev[64];
        int i, loop_fd;
@@ -95,12 +103,15 @@ char *crypt_loop_get_device(void)
        return strdup(dev);
 }
 
-int crypt_loop_attach(const char *loop, const char *file, int offset,
+int crypt_loop_attach(char **loop, const char *file, int offset,
                      int autoclear, int *readonly)
 {
        struct loop_info64 lo64 = {0};
+       char *lo_file_name;
        int loop_fd = -1, file_fd = -1, r = 1;
 
+       *loop = NULL;
+
        file_fd = open(file, (*readonly ? O_RDONLY : O_RDWR) | O_EXCL);
        if (file_fd < 0 && (errno == EROFS || errno == EACCES) && !*readonly) {
                *readonly = 1;
@@ -109,18 +120,33 @@ int crypt_loop_attach(const char *loop, const char *file, int offset,
        if (file_fd < 0)
                goto out;
 
-       loop_fd = open(loop, *readonly ? O_RDONLY : O_RDWR);
-       if (loop_fd < 0)
-               goto out;
+       while (loop_fd < 0)  {
+               *loop = crypt_loop_get_device();
+               if (!*loop)
+                       goto out;
+
+               loop_fd = open(*loop, *readonly ? O_RDONLY : O_RDWR);
+               if (loop_fd < 0)
+                       goto out;
+
+               if (ioctl(loop_fd, LOOP_SET_FD, file_fd) < 0) {
+                       if (errno != EBUSY)
+                               goto out;
+                       free(*loop);
+                       *loop = NULL;
 
-       strncpy((char*)lo64.lo_file_name, file, LO_NAME_SIZE);
+                       close(loop_fd);
+                       loop_fd = -1;
+               }
+       }
+
+       lo_file_name = (char*)lo64.lo_file_name;
+       lo_file_name[LO_NAME_SIZE-1] = '\0';
+       strncpy(lo_file_name, file, LO_NAME_SIZE-1);
        lo64.lo_offset = offset;
        if (autoclear)
                lo64.lo_flags |= LO_FLAGS_AUTOCLEAR;
 
-       if (ioctl(loop_fd, LOOP_SET_FD, file_fd) < 0)
-               goto out;
-
        if (ioctl(loop_fd, LOOP_SET_STATUS64, &lo64) < 0) {
                (void)ioctl(loop_fd, LOOP_CLR_FD, 0);
                goto out;
@@ -142,6 +168,10 @@ out:
                close(loop_fd);
        if (file_fd >= 0)
                close(file_fd);
+       if (r && *loop) {
+               free(*loop);
+               *loop = NULL;
+       }
        return r ? -1 : loop_fd;
 }
 
@@ -160,6 +190,21 @@ int crypt_loop_detach(const char *loop)
        return r;
 }
 
+int crypt_loop_resize(const char *loop)
+{
+       int loop_fd = -1, r = 1;
+
+       loop_fd = open(loop, O_RDONLY);
+       if (loop_fd < 0)
+                return 1;
+
+       if (!ioctl(loop_fd, LOOP_SET_CAPACITY, 0))
+               r = 0;
+
+       close(loop_fd);
+       return r;
+}
+
 static char *_ioctl_backing_file(const char *loop)
 {
        struct loop_info64 lo64 = {0};
@@ -210,7 +255,12 @@ static char *_sysfs_backing_file(const char *loop)
 
 char *crypt_loop_backing_file(const char *loop)
 {
-       char *bf = _sysfs_backing_file(loop);
+       char *bf;
+
+       if (!crypt_loop_device(loop))
+               return NULL;
+
+       bf = _sysfs_backing_file(loop);
        return bf ?: _ioctl_backing_file(loop);
 }