qemu/0319-nbd-fixes-to-read-only-handling.patch
Cole Robinson 9290838132 Fix boot hang if console is not connected (bz #894451)
Fix segfault with zero length virtio-scsi disk (bz #847549)
2013-02-02 15:47:37 -05:00

60 lines
1.9 KiB
Diff

From bcbf10c15f43cfc079622c25ef282688965a7128 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Tue, 13 Nov 2012 10:34:17 +0100
Subject: [PATCH] nbd: fixes to read-only handling
We do not need BLKROSET if the kernel supports setting flags.
Also, always do BLKROSET even for a read-write export, otherwise
the read-only state remains "sticky" after the invocation of
"qemu-nbd -r".
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit c8969eded252058e90e91f12f75f32aceae46ec9)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
nbd.c | 25 ++++++++++++-------------
1 file changed, 12 insertions(+), 13 deletions(-)
diff --git a/nbd.c b/nbd.c
index 206f75c..19f6cd8 100644
--- a/nbd.c
+++ b/nbd.c
@@ -399,24 +399,23 @@ int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize)
return -serrno;
}
- if (flags & NBD_FLAG_READ_ONLY) {
- int read_only = 1;
- TRACE("Setting readonly attribute");
-
- if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
+ if (ioctl(fd, NBD_SET_FLAGS, flags) < 0) {
+ if (errno == ENOTTY) {
+ int read_only = (flags & NBD_FLAG_READ_ONLY) != 0;
+ TRACE("Setting readonly attribute");
+
+ if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {
+ int serrno = errno;
+ LOG("Failed setting read-only attribute");
+ return -serrno;
+ }
+ } else {
int serrno = errno;
- LOG("Failed setting read-only attribute");
+ LOG("Failed setting flags");
return -serrno;
}
}
- if (ioctl(fd, NBD_SET_FLAGS, flags) < 0
- && errno != ENOTTY) {
- int serrno = errno;
- LOG("Failed setting flags");
- return -serrno;
- }
-
TRACE("Negotiation ended");
return 0;