[Qemu-devel] [PATCH v3] raw-posix.c: Make physical devices usable in QEMU under Mac OS X host

[Programmingkid]

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. 

Signed-off-by: John Arbuckle <address@hidden>

---

Replaced strncpy with pstrcpy.

Eliminated the setupDevice function.

Placed helpful error message after call to raw_open_common().

 block/raw-posix.c |  100 ++++++++++++++++++++++++++++++++++++++---------------

 1 files changed, 72 insertions(+), 28 deletions(-)

diff --git a/block/raw-posix.c b/block/raw-posix.c

index cbe6574..5e4ddda 100644

--- a/block/raw-posix.c

+++ b/block/raw-posix.c

@@ -42,9 +42,8 @@

 #include <IOKit/storage/IOMediaBSDClient.h>

 #include <IOKit/storage/IOMedia.h>

 #include <IOKit/storage/IOCDMedia.h>

-//#include <IOKit/storage/IOCDTypes.h>

 #include <CoreFoundation/CoreFoundation.h>

-#endif

+#endif /* (__APPLE__) && (__MACH__) */

 

 #ifdef __sun__

 #define _POSIX_PTHREAD_SEMANTICS 1

@@ -1972,8 +1971,9 @@ 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 );

+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 )

 {

@@ -2001,7 +2001,8 @@ kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator )

     return kernResult;

 }

 

-kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex maxPathSize )

+kern_return_t GetBSDPath(io_iterator_t mediaIterator, char *bsdPath,

+                         CFIndex maxPathSize, int flags)

 {

     io_object_t     nextMedia;

     kern_return_t   kernResult = KERN_FAILURE;

@@ -2014,7 +2015,9 @@ kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex ma

         if ( bsdPathAsCFString ) {

             size_t devPathLength;

             strcpy( bsdPath, _PATH_DEV );

-            strcat( bsdPath, "r" );

+            if (flags & BDRV_O_NOCACHE) {

+                strcat(bsdPath, "r");

+            }

             devPathLength = strlen( bsdPath );

             if ( CFStringGetCString( bsdPathAsCFString, bsdPath + devPathLength, maxPathSize - devPathLength, kCFStringEncodingASCII ) ) {

                 kernResult = KERN_SUCCESS;

@@ -2027,7 +2030,35 @@ kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex ma

     return kernResult;

 }

 

-#endif

+/* Sets up a real cdrom for use in QEMU */

+static bool setupCDROM(char *bsdPath)

+{

+    int index, numOfTestPartitions = 2, fd;

+    char testPartition[MAXPATHLEN];

+    bool partitionFound = false;

+

+    /* look for a working partition */

+    for (index = 0; index < numOfTestPartitions; index++) {

+        pstrcpy(testPartition, strlen(bsdPath)+1, bsdPath);

+        snprintf(testPartition, MAXPATHLEN, "%ss%d", testPartition, index);

+        fd = qemu_open(testPartition, O_RDONLY | O_BINARY | O_LARGEFILE);

+        if (fd >= 0) {

+            partitionFound = true;

+            qemu_close(fd);

+            break;

+        }

+    }

+

+    /* if a working partition on the device was not found */

+    if (partitionFound == false) {

+        printf("Error: Failed to find a working partition on disc!\n");

+    } else {

+        DPRINTF("Using %s as optical disc\n", testPartition);

+        pstrcpy(bsdPath, strlen(testPartition)+1, testPartition);

+    }

+    return partitionFound;

+}

+#endif /* defined(__APPLE__) && defined(__MACH__) */

 

 static int hdev_probe_device(const char *filename)

 {

@@ -2115,34 +2146,33 @@ static int hdev_open(BlockDriverState *bs, QDict *options, int flags,

     BDRVRawState *s = bs->opaque;

     Error *local_err = NULL;

     int ret;

+    bool cdromOK = true;

 

 #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 ) );

-

-        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';

+    /* If using a physical device */

+    if (strstart(filename, "/dev/", NULL)) {

+        char bsdPath[MAXPATHLEN];

+

+        /* If the physical device is a cdrom */

+        if (strcmp(filename, "/dev/cdrom") == 0) {

+            io_iterator_t mediaIterator;

+            FindEjectableCDMedia(&mediaIterator);

+            GetBSDPath(mediaIterator, bsdPath, sizeof(bsdPath), flags);

+            if (bsdPath[0] == '\0') {

+                printf("Error: failed to obtain bsd path for optical drive!\n");

             } else {

-                qemu_close(fd);

+                cdromOK = setupCDROM(bsdPath);

+                filename = bsdPath;

+            }

+

+            if (mediaIterator) {

+                IOObjectRelease(mediaIterator);

             }

-            filename = bsdPath;

-            qdict_put(options, "filename", qstring_from_str(filename));

         }

 

-        if ( mediaIterator )

-            IOObjectRelease( mediaIterator );

+        qdict_put(options, "filename", qstring_from_str(filename));

     }

 #endif

 

@@ -2153,7 +2183,21 @@ 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 && (cdromOK == false || ret != 0)) {

+        printf("If device %s is mounted on the desktop, unmount it"

+                        " first before using it in QEMU.\n", filename);

+        printf("Command to unmount device: diskutil unmountDisk %s\n",

+                                                                    filename);

+        printf("Command to mount device: diskutil mountDisk %s\n", filename);

+    }

+#endif /* defined(__APPLE__) && defined(__MACH__) */

+

+    if (ret < 0) {

+       return ret;

     }

 

     /* Since this does ioctl the device must be already opened */

-- 

1.7.5.4