From 3e05c785516efa6911504b1ddf936d2386c2e0b6 Mon Sep 17 00:00:00 2001 From: Chunyan Liu Date: Fri, 2 Dec 2011 23:27:54 +0800 Subject: Update ioctl order in nbd_init() to detect EBUSY Update ioctl(s) in nbd_init() to detect device busy early. Current nbd_init() issues NBD_CLEAR_SOCKET before NBD_SET_SOCKET, if issuing "qemu-nbd -c /dev/nbd0 disk.img" twice, the second time won't detect EBUSY in nbd_init(), but in nbd_client will report EBUSY and do clear socket (the 1st time command will be affacted too because of no socket any more.) No change to previous version. Signed-off-by: Chunyan Liu Signed-off-by: Paolo Bonzini --- nbd.c | 27 +++++++++------------------ 1 file changed, 9 insertions(+), 18 deletions(-) (limited to 'nbd.c') diff --git a/nbd.c b/nbd.c index 7ab1b1f5c0..73fedeb9ad 100644 --- a/nbd.c +++ b/nbd.c @@ -358,6 +358,15 @@ int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, #ifdef __linux__ int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) { + TRACE("Setting NBD socket"); + + if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { + int serrno = errno; + LOG("Failed to set NBD socket"); + errno = serrno; + return -1; + } + TRACE("Setting block size to %lu", (unsigned long)blocksize); if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) == -1) { @@ -396,24 +405,6 @@ int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) return -1; } - TRACE("Clearing NBD socket"); - - if (ioctl(fd, NBD_CLEAR_SOCK) == -1) { - int serrno = errno; - LOG("Failed clearing NBD socket"); - errno = serrno; - return -1; - } - - TRACE("Setting NBD socket"); - - if (ioctl(fd, NBD_SET_SOCK, csock) == -1) { - int serrno = errno; - LOG("Failed to set NBD socket"); - errno = serrno; - return -1; - } - TRACE("Negotiation ended"); return 0; -- cgit v1.2.1