> On Fri, 13 Aug 2010, Randy Dunlap wrote:
>> On Fri, 13 Aug 2010 10:40:40 -0700 Sage Weil wrote:
>>
>>> From: Yehuda Sadeh <yehuda@hq.newdream.net>
>>>
>>> The rados block device (rbd), based on osdblk, creates a block device
>>> that is backed by objects stored in the Ceph distributed object storage
>>> cluster. Each device consists of a single metadata object and data
>>> striped over many data objects.
>>>
>>> The rbd driver supports read-only snapshots.
>>>
>>> Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
>>> Signed-off-by: Sage Weil <sage@newdream.net>
>>> ---
>>> MAINTAINERS | 9 +
>>> drivers/block/Kconfig | 13 +
>>> drivers/block/Makefile | 1 +
>>> drivers/block/rbd.c | 1844 +++++++++++++++++++++++++++++++++++++++++++++
>>> drivers/block/rbd_types.h | 73 ++
>>> 5 files changed, 1940 insertions(+), 0 deletions(-)
>>> create mode 100644 drivers/block/rbd.c
>>> create mode 100644 drivers/block/rbd_types.h
>>>
>>> diff --git a/MAINTAINERS b/MAINTAINERS
>>> index 5102922..cb34b1b 100644
>>> --- a/MAINTAINERS
>>> +++ b/MAINTAINERS
>>> @@ -4694,6 +4694,15 @@ F: fs/qnx4/
>>> F: include/linux/qnx4_fs.h
>>> F: include/linux/qnxtypes.h
>>>
>>> +RADOS BLOCK DEVICE (RBD)
>>> +F: include/linux/qnxtypes.h
>>> +M: Yehuda Sadeh <yehuda@hq.newdream.net>
>>> +M: Sage Weil <sage@newdream.net>
>>> +M:
ceph-devel@vger.kernel.org
>>> +S: Supported
>>> +F: drivers/block/rbd.c
>>> +F: drivers/block/rbd_types.h
>>> +
>>> RADEON FRAMEBUFFER DISPLAY DRIVER
>>> M: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>>> L:
linux-fbdev@vger.kernel.org
>>> diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
>>> index de27768..708104b 100644
>>> --- a/drivers/block/Kconfig
>>> +++ b/drivers/block/Kconfig
>>> @@ -488,4 +488,17 @@ config BLK_DEV_HD
>>>
>>> If unsure, say N.
>>>
>>> +config BLK_DEV_RBD
>>> + tristate "Rados block device (RBD)"
>>> + select CEPH_LIB
>>> + default n
>>> + help
>>> + Say Y here if you want include the Rados block device, which stripes
>>> + a block device over objects stored in the Ceph distributed object
>>> + store.
>>> +
>>> + More information at
http://ceph.newdream.net/.
>>> +
>>> + If unsure, say N.
>>> +
>>> endif # BLK_DEV
>>
>> In linux-next of 20100813, I get:
>>
>> net/built-in.o: In function `read_partial_message_section':
>> messenger.c:(.text+0x6598b): undefined reference to `crc32c'
>> net/built-in.o: In function `read_partial_message_bio':
>> messenger.c:(.text+0x65a57): undefined reference to `crc32c'
>> net/built-in.o: In function `write_partial_msg_pages':
>> messenger.c:(.text+0x65e22): undefined reference to `crc32c'
>> net/built-in.o: In function `prepare_write_message':
>> messenger.c:(.text+0x66219): undefined reference to `crc32c'
>> messenger.c:(.text+0x66240): undefined reference to `crc32c'
>> net/built-in.o:messenger.c:(.text+0x66264): more undefined references to `crc32c' follow
>>
>> when CONFIG_INET is not enabled. It looks like BLK_DEV_RBD needs to depend on
>> INET and possibly on BLOCK (I sent a patch for depends on BLOCK on 2010-aug-04
>> due to other build errors).
>
> I see the problem: BLK_DEV_RBD and CEPH_FS both have 'select CEPH_LIB' and
> CEPH_LIB depends on INET and selects LIBCRC32C, but kconfig doesn't
> propagate those backward dependencies for you. It looks like CEPH_FS and
> BLK_DEV_RBD should then depend on/select CEPH_LIB _and_ its dependencies.
> Patching that (and the BLOCK dependency) up now...
>
> Unless there is a better way to do it?
