From 221f715d90ec5fec569a19119887445c037bca86 Mon Sep 17 00:00:00 2001 From: aliguori Date: Sat, 28 Mar 2009 17:28:41 +0000 Subject: new scsi-generic abstraction, use SG_IO (Christoph Hellwig) Okay, I started looking into how to handle scsi-generic I/O in the new world order. I think the best is to use the SG_IO ioctl instead of the read/write interface as that allows us to support scsi passthrough on disk/cdrom devices, too. See Hannes patch on the kvm list from August for an example. Now that we always do ioctls we don't need another abstraction than bdrv_ioctl for the synchronous requests for now, and for asynchronous requests I've added a aio_ioctl abstraction keeping it simple. Long-term we might want to move the ops to a higher-level abstraction and let the low-level code fill out the request header, but I'm lazy enough to leave that to the people trying to support scsi-passthrough on a non-Linux OS. Tested lightly by issuing various sg_ commands from sg3-utils in a guest to a host CDROM device. Signed-off-by: Christoph Hellwig Signed-off-by: Anthony Liguori git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6895 c046a42c-6fe2-441c-8c8c-71466251a162 --- posix-aio-compat.h | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'posix-aio-compat.h') diff --git a/posix-aio-compat.h b/posix-aio-compat.h index 0bc10f5e08..a1cdfd7f1f 100644 --- a/posix-aio-compat.h +++ b/posix-aio-compat.h @@ -29,12 +29,16 @@ struct qemu_paiocb int aio_fildes; void *aio_buf; size_t aio_nbytes; +#define aio_ioctl_cmd aio_nbytes /* for QEMU_PAIO_IOCTL */ int ev_signo; off_t aio_offset; /* private */ TAILQ_ENTRY(qemu_paiocb) node; - int is_write; + int aio_type; +#define QEMU_PAIO_READ 0x01 +#define QEMU_PAIO_WRITE 0x02 +#define QEMU_PAIO_IOCTL 0x03 ssize_t ret; int active; }; @@ -49,6 +53,7 @@ struct qemu_paioinit int qemu_paio_init(struct qemu_paioinit *aioinit); int qemu_paio_read(struct qemu_paiocb *aiocb); int qemu_paio_write(struct qemu_paiocb *aiocb); +int qemu_paio_ioctl(struct qemu_paiocb *aiocb); int qemu_paio_error(struct qemu_paiocb *aiocb); ssize_t qemu_paio_return(struct qemu_paiocb *aiocb); int qemu_paio_cancel(int fd, struct qemu_paiocb *aiocb); -- cgit v1.2.1