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2018-07-03Tools: hv: vss: fix loop device detectionVitaly Kuznetsov1-4/+61
Commit ea81fdf0981d ("Tools: hv: vss: Skip freezing filesystems backed by loop") added skip for filesystems backed by loop device. However, it seems the detection of such cases is incomplete. It was found that with 'devicemapper' storage driver docker creates the following chain: NAME MAJ:MIN loop0 7:0 ..docker-8:4-8473394-pool 253:0 ..docker-8:4-8473394-eac... 253:1 so when we're looking at the mounted device we see major '253' and not '7'. Solve the issue by walking /sys/dev/block/*/slaves chain and checking if there's a loop device somewhere. Other than that, don't skip mountpoints silently when stat() fails. In case e.g. SELinux is failing stat we don't want to skip freezing everything without letting user know about the failure. Fixes: ea81fdf0981d ("Tools: hv: vss: Skip freezing filesystems backed by loop") Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-06tools: hv: fix compiler warnings about major/target_fnameDexuan Cui1-0/+1
This patch fixes the below warnings with new glibc and gcc: hv_vss_daemon.c:100:13: warning: In the GNU C Library, "major" is defined by <sys/sysmacros.h>. For historical compatibility, it is currently defined by <sys/types.h> as well, but we plan to remove this soon. To use "major", include <sys/sysmacros.h> directly. hv_fcopy_daemon.c:42:2: note: 'snprintf' output between 2 and 1040 bytes into a destination of size 260 Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-16Tools: hv: vss: Skip freezing filesystems backed by loopAlex Ng1-0/+7
Since a loop device is backed by a file, a backup will already result in its parent filesystem being frozen. It's sufficient to just freeze the parent filesystem, so we can skip the loop device. This avoids a situation where a loop device and its parent filesystem are both frozen and then thawed out of order. For example, if the loop device is enumerated first, we would thaw it while its parent filesystem is still frozen. The thaw operation fails and the loop device remains frozen. Signed-off-by: Alex Ng <alexng@messages.microsoft.com> Signed-off-by: Vyronas Tsingaras <vyronas@vtsingaras.me> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-18Tools: hv: vss: Thaw the filesystem and continue if freeze call has timed outAlex Ng1-1/+3
If a FREEZE operation takes too long, the driver may time out and move on to another operation. The daemon is unaware of this and attempts to notify the driver that the FREEZE succeeded. This results in an error from the driver and the daemon leaves the filesystem in frozen state. Fix this by thawing the filesystem and continuing. Signed-off-by: Michael Gissing <mg@faulpeltz.net> Signed-off-by: Alex Ng <alexng@messages.microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02Drivers: hv: utils: Check VSS daemon is listening before a hot backupAlex Ng1-0/+3
Hyper-V host will send a VSS_OP_HOT_BACKUP request to check if guest is ready for a live backup/snapshot. The driver should respond to the check only if the daemon is running and listening to requests. This allows the host to fallback to standard snapshots in case the VSS daemon is not running. Signed-off-by: Alex Ng <alexng@messages.microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14tools: hv: vss: fix the write()'s argument: error -> vss_msgDexuan Cui1-1/+1
Fix the write()'s argument in the daemon code. Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Signed-off-by: Dexuan Cui <decui@microsoft.com> Cc: stable@vger.kernel.org Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24Drivers: hv: vss: full handshake supportVitaly Kuznetsov1-0/+14
Introduce VSS_OP_REGISTER1 to support kernel replying to the negotiation message with its own version. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Alex Ng <alexng@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24Tools: hv: vss: use misc char device to communicate with kernelVitaly Kuznetsov1-114/+25
Use /dev/vmbus/hv_vss instead of netlink. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Tested-by: Alex Ng <alexng@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-25hv: hypervvssd: call endmntent before call setmntent againVaughan Cao1-2/+8
If freeze fails, vss_operate will re-enter itself to thaw. But it forgets to call endmntent() before it recalls setmntent() again. Signed-off-by: Vaughan Cao <vaughan.cao@oracle.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-26Tools: hv: vssdaemon: skip all filesystems mounted readonlyVitaly Kuznetsov1-1/+1
Instead of making a list of exceptions for readonly filesystems in addition to iso9660 we already have it is better to skip freeze operation for all readonly-mounted filesystems. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Acked-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-26Tools: hv: vssdaemon: report freeze errorsVitaly Kuznetsov1-4/+12
When ioctl(fd, FIFREEZE, 0) results in an error we cannot report it to syslog instantly since that can cause write to a frozen disk. However, the name of the filesystem which caused the error and errno are valuable and we would like to get a nice human-readable message in the log. Save errno before calling vss_operate(VSS_OP_THAW) and report the error right after. Unfortunately, FITHAW errors cannot be reported the same way as we need to finish thawing all filesystems before calling syslog(). We should also avoid calling endmntent() for the second time in case we encountered an error during freezing of '/' as it usually results in SEGSEGV. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Acked-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07tools: hv: introduce -n/--no-daemon optionVitaly Kuznetsov1-2/+31
All tools/hv daemons do mandatory daemon() on startup. However, no pidfile is created, this make it difficult for an init system to track such daemons. Modern linux distros use systemd as their init system. It can handle the daemonizing by itself, however, it requires a daemon to stay in foreground for that. Some distros already carry distro-specific patch for hv tools which switches off daemon(). Introduce -n/--no-daemon option for all 3 daemons in hv/tools. Parse options with getopt() to make this part easily expandable. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07Tools: hv: vssdaemon: ignore the EBUSY on multiple freezing the same partitionDexuan Cui1-8/+40
If a partition appears mounted more than once in /proc/mounts, vss_do_freeze() succeeds only for the first time and gets EBUSY (on freeze) or EINVAL (on thaw) for the second time. The patch ignores these to make the backup feature work. Also improved the error handling in case a freeze operation fails. Signed-off-by: Dexuan Cui <decui@microsoft.com> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-15Tools: hv: vssdaemon: Ignore VFAT mounts during the Freeze operationK. Y. Srinivasan1-0/+2
If the guest has a FAT file system mounted, skip it during the FREEZE operation. With this change we can support host initiated backup of the guest even when the guest may have FAT file systems mounted. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-08Tools: hv: remove inclusion of linux/types.hOlaf Hering1-1/+0
With very old libc headers the inclusion of sys/types.h causes conflicts with linux/types.h. Since the latter is not required anyway, remove it from the source files. If any of the headers really needs linux/types.h it has to include it itself. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-09-26Tools: hv: use single send+recv bufferOlaf Hering1-5/+3
send_buffer is used only once during registration. To reduce runtime memory usage reuse the recv_buffer for registration. Also use NLMSG_LENGTH instead of NLMSG_HDRLEN to take alignment into account. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12Tools: hv: use full nlmsghdr in netlink_sendOlaf Hering1-10/+5
There is no need to have a nlmsghdr pointer to another temporary buffer. Instead use a full struct nlmsghdr. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-12Tools: hv: correct payload size in netlink_sendOlaf Hering1-1/+1
netlink_send is supposed to send just the cn_msg+hv_kvp_msg via netlink. Currently it sets an incorrect iovec size, as reported by valgrind. In the case of registering with the kernel the allocated buffer is large enough to hold nlmsghdr+cn_msg+hv_kvp_msg, no overrun happens. In the case of responding to the kernel the cn_msg is located in the middle of recv_buffer, after the nlmsghdr. Currently the code in netlink_send adds also the size of nlmsghdr to the payload. But nlmsghdr is a separate iovec. This leads to an (harmless) out-of-bounds access when the kernel processes the iovec. Correct the iovec size of the cn_msg to be just cn_msg + its payload. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-02Tools: hv: fix send/recv buffer allocationOlaf Hering1-3/+12
hv_kvp_daemon fails to start in current openSuSE 13.1 snapshots because the kvp_send_buffer is too small to hold cn_msg+hv_kvp_msg, the very first sendmsg returns with EFAULT. In addition it fixes the Network info tab in Windows Server 2012R2 in SLES11. Adjust the code in kvp and vss daemon to allocate the needed buffers at runtime. To keep the code simple, the buffer_len includes also the nlmsghdr, although only the recv_buffer needs this extra space. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26tools: hv: Check return value of setsockopt callTomas Hozza1-1/+5
Check return value of setsockopt call and if it fails print error to the system log and exit with non-zero value. Signed-off-by: Tomas Hozza <thozza@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26tools: hv: Check return value of poll callTomas Hozza1-1/+10
Check return value of poll call and if it fails print error to the system log. If errno is EINVAL then exit with non-zero value otherwise continue the while loop and call poll again. Signed-off-by: Tomas Hozza <thozza@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26tools: hv: Improve error logging in VSS daemon.Tomas Hozza1-4/+6
Use errno and strerror() when logging errors to provide more information. Signed-off-by: Tomas Hozza <thozza@redhat.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24Tools: hv: Fix a checkpatch warningK. Y. Srinivasan1-1/+1
Fix a checkpatch warning. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24tools: hv: skip iso9660 mounts in hv_vss_daemonOlaf Hering1-0/+2
fsreeze does not work for iso9660 filesystems. A ENOSUPP may be caught in the freeze case, but the subsequent thaw call would fail and leads to a false error. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24tools: hv: use FIFREEZE/FITHAW in hv_vss_daemonOlaf Hering1-9/+22
As suggested by Paolo Bonzini, use ioctl instead of calling fsfreeze. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24tools: hv: use getmntent in hv_vss_daemonOlaf Hering1-18/+21
As suggested by Paolo Bonzini, use getmntent instead of parsing output of mount(1). Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24Tools: hv: Fix a checkpatch warningK. Y. Srinivasan1-2/+3
Fix a checkpatch warning. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24tools: hv: fix checks for origin of netlink message in hv_vss_daemonOlaf Hering1-1/+7
Similar to what commit 95a69adab9acfc3981c504737a2b6578e4d846ef ("tools: hv: Netlink source address validation allows DoS") does in hv_kvp_daemon, improve checks for origin of netlink connector message. Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-24Tools: hv: fix warnings in hv_vss_daemonOlaf Hering1-4/+8
This change fixes a few compile errors: hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/' hv_vss_daemon.c:64:15: warning: unknown escape sequence '\/' hv_vss_daemon.c: In function 'vss_operate': hv_vss_daemon.c:66: warning: 'return' with no value, in function returning non-void hv_vss_daemon.c: In function 'main': hv_vss_daemon.c:130: warning: ignoring return value of 'daemon', declared with attribute warn_unused_result hv_vss_daemon.c: In function 'vss_operate': hv_vss_daemon.c:47: warning: 'fs_op' may be used uninitialized in this function Signed-off-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-15Drivers: hv: Add a new driver to support host initiated backupK. Y. Srinivasan1-0/+220
This driver supports host initiated backup of the guest. On Windows guests, the host can generate application consistent backups using the Windows VSS framework. On Linux, we ensure that the backup will be file system consistent. This driver allows the host to initiate a "Freeze" operation on all the mounted file systems in the guest. Once the mounted file systems in the guest are frozen, the host snapshots the guest's file systems. Once this is done, the guest's file systems are "thawed". This driver has a user-level component (daemon) that invokes the appropriate operation on all the mounted file systems in response to the requests from the host. The duration for which the guest is frozen is very short - a few seconds. During this interval, the diff disk is comitted. In this version of the patch I have addressed the feedback from Olaf Herring. Also, some of the connector related issues have been fixed. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Cc: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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