On Jun 28, 2015, at 8:29 PM, Laurent Vivier wrote:
> Hi,
>
> On 29/06/2015 01:43, Programmingkid wrote:
>>
>> On Jun 25, 2015, at 2:01 PM, Peter Maydell wrote:
>>
>>> On 25 June 2015 at 18:56, Programmingkid
>>> <programmingk...@gmail.com> wrote:
>>>> Nice to hear from you again Laurent. The only way a solution in
>>>> hdev_open() would work is if it could prevent
>>>> find_image_format() from executing. Otherwise find_image_format()
>>>> would just quit QEMU with an error.
>>>
>>> The question you should be asking is "what is Linux doing for raw
>>> CDROM devices that is different, such that it works there but
>>> doesn't work on OSX?".
>>>
>>> It would also be helpful to know which is the case that doesn't
>>> work. Does QEMU fail in all cases, or only if the cdrom drive is
>>> empty, or only if there's a disk in the drive?
>>
>> QEMU fails if the cdrom is specified "-cdrom /dev/cdrom", and there
>> is no cd in the drive.
>>
>> QEMU also fails with a real cdrom in the drive.
>>
>>>
>>> My initial suspicion is that we need OSX support in raw-posix.c for
>>> handling the host CDROM specially -- note that Linux and FreeBSD
>>> register a bdrv_host_cdrom with an is_inserted function.
>>
>> The is_inserted function wouldn't make a difference.
>
> In fact, if your patch fixes the problem, the is_inserted with no
> cdrom should too:
>
> with your " strcmp("/dev/cdrom", filename) == 0 ", you force the
> selection of bdrv_raw (which is what to do).
>
> without your patch, if "bdrv_is_inserted()" was implemented and no cdrom
> in the drive " !bdrv_is_inserted(bs) " should also select bdrv_raw.
>
> It appears also that bdrv_host_cdrom is not registered in
> bdrv_file_init(). I think this is the missing part to have a host cdrom
> support on MacOS X.
>
> Laurent
This patch is what I came up with using your idea. It uses the fact that the
bdrv_is_inserted() function is called first from find_image_format(). The
bdrv_is_inserted() function now points to cdrom_is_inserted(). This new
function will return 0 the first time it is called, then 1 after that. So far
it works.
---
block/raw-posix.c | 21 +++++++++++++++++++++
1 files changed, 21 insertions(+), 0 deletions(-)
diff --git a/block/raw-posix.c b/block/raw-posix.c
index a967464..2d35580 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -2324,6 +2324,23 @@ static int hdev_create(const char *filename, QemuOpts
*opts,
return ret;
}
+#ifdef __APPLE__
+
+static int cdrom_is_inserted(BlockDriverState *bs)
+{
+ static int count = 0;
+ int returnValue = 1;
+
+ if(count == 0) {
+ returnValue = 0; // get around find_image_format() issue
+ }
+
+ printf("count = %d for %s, returning %d\n", count, bs->filename,
returnValue);
+ count++;
+ return returnValue;
+}
+#endif
+
static BlockDriver bdrv_host_device = {
.format_name = "host_device",
.protocol_name = "host_device",
@@ -2365,6 +2382,10 @@ static BlockDriver bdrv_host_device = {
.bdrv_ioctl = hdev_ioctl,
.bdrv_aio_ioctl = hdev_aio_ioctl,
#endif
+
+#ifdef __APPLE__
+ .bdrv_is_inserted = cdrom_is_inserted,
+#endif
};
#ifdef __linux__
--
1.7.5.4
