diff mbox

[v13] block/raw-posix.c: Make physical devices usable in QEMU under Mac OS X host

Message ID 12769368-5AE5-4B40-B379-8B03F97E80F7@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Programmingkid Jan. 19, 2016, 8:38 p.m. UTC
Mac OS X can be picky when it comes to allowing the user
to use physical devices in QEMU. Most mounted volumes
appear to be off limits to QEMU. If an issue is detected,
a message is displayed showing the user how to unmount a
volume. Now QEMU uses both CD and DVD media.

Signed-off-by: John Arbuckle <programmingkidx@gmail.com>

---
Added continue statement to the kernResult != KERN_SUCCESS if condition in 
FindEjectableCDMedia().
Moved print_unmounting_directions() to only compile under Mac OS X. 
Fixed indentation of "setup_cdrom(bsd_path, errp) == false) {".
Replaced IOCDMedia with kIOCDMediaClass.
Changed filename variable to a character array.
Changed how filename was set to bsd_path's value by using snprintf().
Removed "goto continue_as_normal" code.
Added error_occurred variable.
Moved "if (strncmp(filename, "/dev/", 5) == 0 && ret != 0)" code to inside of 
"if (ret < 0)" block. 

 block/raw-posix.c |  169 ++++++++++++++++++++++++++++++++++++++++-------------
 1 files changed, 127 insertions(+), 42 deletions(-)
diff mbox

Patch

diff --git a/block/raw-posix.c b/block/raw-posix.c
index 076d070..67dc166 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -43,6 +43,7 @@ 
 #include <IOKit/storage/IOMedia.h>
 #include <IOKit/storage/IOCDMedia.h>
 //#include <IOKit/storage/IOCDTypes.h>
+#include <IOKit/storage/IODVDMedia.h>
 #include <CoreFoundation/CoreFoundation.h>
 #endif
 
@@ -1971,33 +1972,47 @@  BlockDriver bdrv_file = {
 /* host device */
 
 #if defined(__APPLE__) && defined(__MACH__)
-static kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator );
 static kern_return_t GetBSDPath(io_iterator_t mediaIterator, char *bsdPath,
                                 CFIndex maxPathSize, int flags);
-kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator )
+static char *FindEjectableOpticalMedia(io_iterator_t *mediaIterator)
 {
-    kern_return_t       kernResult;
+    kern_return_t kernResult = KERN_FAILURE;
     mach_port_t     masterPort;
     CFMutableDictionaryRef  classesToMatch;
+    const char *matching_array[] = {kIODVDMediaClass, kIOCDMediaClass};
+    char *mediaType = NULL;
 
     kernResult = IOMasterPort( MACH_PORT_NULL, &masterPort );
     if ( KERN_SUCCESS != kernResult ) {
         printf( "IOMasterPort returned %d\n", kernResult );
     }
 
-    classesToMatch = IOServiceMatching( kIOCDMediaClass );
-    if ( classesToMatch == NULL ) {
-        printf( "IOServiceMatching returned a NULL dictionary.\n" );
-    } else {
-    CFDictionarySetValue( classesToMatch, CFSTR( kIOMediaEjectableKey ), kCFBooleanTrue );
-    }
-    kernResult = IOServiceGetMatchingServices( masterPort, classesToMatch, mediaIterator );
-    if ( KERN_SUCCESS != kernResult )
-    {
-        printf( "IOServiceGetMatchingServices returned %d\n", kernResult );
-    }
+    int index;
+    for (index = 0; index < ARRAY_SIZE(matching_array); index++) {
+        classesToMatch = IOServiceMatching(matching_array[index]);
+        if (classesToMatch == NULL) {
+            error_report("IOServiceMatching returned NULL for %s",
+                         matching_array[index]);
+            continue;
+        }
+        CFDictionarySetValue(classesToMatch, CFSTR(kIOMediaEjectableKey),
+                             kCFBooleanTrue);
+        kernResult = IOServiceGetMatchingServices(masterPort, classesToMatch,
+                                                  mediaIterator);
+        if (kernResult != KERN_SUCCESS) {
+            error_report("Note: IOServiceGetMatchingServices returned %d",
+                         kernResult);
+            continue;
+        }
 
-    return kernResult;
+        /* If a match was found, leave the loop */
+        if (*mediaIterator != 0) {
+            DPRINTF("Matching using %s\n", matching_array[index]);
+            mediaType = g_strdup(matching_array[index]);
+            break;
+        }
+    }
+    return mediaType;
 }
 
 kern_return_t GetBSDPath(io_iterator_t mediaIterator, char *bsdPath,
@@ -2029,7 +2044,46 @@  kern_return_t GetBSDPath(io_iterator_t mediaIterator, char *bsdPath,
     return kernResult;
 }
 
-#endif
+/* Sets up a real cdrom for use in QEMU */
+static bool setup_cdrom(char *bsd_path, Error **errp)
+{
+    int index, num_of_test_partitions = 2, fd;
+    char test_partition[MAXPATHLEN];
+    bool partition_found = false;
+
+    /* look for a working partition */
+    for (index = 0; index < num_of_test_partitions; index++) {
+        snprintf(test_partition, sizeof(test_partition), "%ss%d", bsd_path,
+                 index);
+        fd = qemu_open(test_partition, O_RDONLY | O_BINARY | O_LARGEFILE);
+        if (fd >= 0) {
+            partition_found = true;
+            qemu_close(fd);
+            break;
+        }
+    }
+
+    /* if a working partition on the device was not found */
+    if (partition_found == false) {
+        error_setg(errp, "Failed to find a working partition on disc");
+    } else {
+        DPRINTF("Using %s as optical disc\n", test_partition);
+        pstrcpy(bsd_path, MAXPATHLEN, test_partition);
+    }
+    return partition_found;
+}
+
+/* Prints directions on mounting and unmounting a device */
+static void print_unmounting_directions(const char *file_name)
+{
+    error_report("If device %s is mounted on the desktop, unmount"
+                 " it first before using it in QEMU", file_name);
+    error_report("Command to unmount device: diskutil unmountDisk %s",
+                 file_name);
+    error_report("Command to mount device: diskutil mountDisk %s", file_name);
+}
+
+#endif /* defined(__APPLE__) && defined(__MACH__) */
 
 static int hdev_probe_device(const char *filename)
 {
@@ -2119,34 +2173,59 @@  static int hdev_open(BlockDriverState *bs, QDict *options, int flags,
     int ret;
 
 #if defined(__APPLE__) && defined(__MACH__)
-    const char *filename = qdict_get_str(options, "filename");
-
-    if (strstart(filename, "/dev/cdrom", NULL)) {
-        kern_return_t kernResult;
-        io_iterator_t mediaIterator;
-        char bsdPath[ MAXPATHLEN ];
-        int fd;
-
-        kernResult = FindEjectableCDMedia( &mediaIterator );
-        kernResult = GetBSDPath(mediaIterator, bsdPath, sizeof(bsdPath),
-                                flags);
-        if ( bsdPath[ 0 ] != '\0' ) {
-            strcat(bsdPath,"s0");
-            /* some CDs don't have a partition 0 */
-            fd = qemu_open(bsdPath, O_RDONLY | O_BINARY | O_LARGEFILE);
-            if (fd < 0) {
-                bsdPath[strlen(bsdPath)-1] = '1';
-            } else {
-                qemu_close(fd);
-            }
-            filename = bsdPath;
-            qdict_put(options, "filename", qstring_from_str(filename));
+    char filename[MAXPATHLEN];
+    bool error_occurred = false;
+    snprintf(filename, MAXPATHLEN, "%s", qdict_get_str(options, "filename"));
+    /* If using a real cdrom */
+    if (strcmp(filename, "/dev/cdrom") == 0) {
+        char bsd_path[MAXPATHLEN];
+        char *mediaType = NULL;
+        kern_return_t ret_val;
+        io_iterator_t mediaIterator = 0;
+
+        mediaType = FindEjectableOpticalMedia(&mediaIterator);
+        if (mediaType == NULL) {
+            error_setg(errp, "Please make sure your CD/DVD is in the optical"
+                       " drive");
+            error_occurred = true;
+            goto hdev_open_Mac_error;
+        }
+
+        ret_val = GetBSDPath(mediaIterator, bsd_path, sizeof(bsd_path), flags);
+        if (ret_val != KERN_SUCCESS) {
+            error_setg(errp, "Could not get BSD path for optical drive");
+            error_occurred = true;
+            goto hdev_open_Mac_error;
+        }
+
+        /* If a real optical drive was not found */
+        if (bsd_path[0] == '\0') {
+            error_setg(errp, "Failed to obtain bsd path for optical drive");
+            error_occurred = true;
+            goto hdev_open_Mac_error;
+        }
+
+        /* If using a cdrom disc and finding a partition on the disc failed */
+        if (strncmp(mediaType, kIOCDMediaClass, 9) == 0 &&
+            setup_cdrom(bsd_path, errp) == false) {
+            print_unmounting_directions(bsd_path);
+            error_occurred = true;
+            goto hdev_open_Mac_error;
         }
 
-        if ( mediaIterator )
-            IOObjectRelease( mediaIterator );
+        snprintf(filename, MAXPATHLEN, "%s", bsd_path);
+        qdict_put(options, "filename", qstring_from_str(filename));
+
+hdev_open_Mac_error:
+        g_free(mediaType);
+        if (mediaIterator) {
+            IOObjectRelease(mediaIterator);
+        }
+        if (error_occurred) {
+            return -1;
+        }
     }
-#endif
+#endif /* defined(__APPLE__) && defined(__MACH__) */
 
     s->type = FTYPE_FILE;
 
@@ -2155,7 +2234,13 @@  static int hdev_open(BlockDriverState *bs, QDict *options, int flags,
         if (local_err) {
             error_propagate(errp, local_err);
         }
-        return ret;
+#if defined(__APPLE__) && defined(__MACH__)
+        /* if a physical device experienced an error while being opened */
+        if (strncmp(filename, "/dev/", 5) == 0) {
+            print_unmounting_directions(filename);
+            return -1;
+        }
+#endif /* defined(__APPLE__) && defined(__MACH__) */
     }
 
     /* Since this does ioctl the device must be already opened */