99c147e2f5
We're about to enable the use of O_DIRECT in the migration code and due to the alignment restrictions imposed by filesystems we need to make sure the flag is only used when doing aligned IO. The migration will do parallel IO to different regions of a file, so we need to use more than one file descriptor. Those cannot be obtained by duplicating (dup()) since duplicated file descriptors share the file status flags, including O_DIRECT. If one migration channel does unaligned IO while another sets O_DIRECT to do aligned IO, the filesystem would fail the unaligned operation. The add-fd QMP command along with the fdset code are specifically designed to allow the user to pass a set of file descriptors with different access flags into QEMU to be later fetched by code that needs to alternate between those flags when doing IO. Extend the fdset matching to behave the same with the O_DIRECT flag. Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Fabiano Rosas <farosas@suse.de> |
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| .. | ||
| fds.c | ||
| hmp-cmds-target.c | ||
| hmp-cmds.c | ||
| hmp-target.c | ||
| hmp.c | ||
| meson.build | ||
| monitor-internal.h | ||
| monitor.c | ||
| qemu-config-qmp.c | ||
| qmp-cmds-control.c | ||
| qmp-cmds.c | ||
| qmp.c | ||
| trace-events | ||
| trace.h | ||