mirror of
https://github.com/checkpoint-restore/criu.git
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89a7a45d37
Usually the PTYs represent a pair of links -- master peer and slave peer. Master peer must be opened before slave. Internally, when kernel creates master peer it also generates a slave interface in a form of /dev/pts/N, where N is that named pty "index". Master/slave connection unambiguously identified by this index. Still, one master can carry multiple slaves -- for example a user opens one master via /dev/ptmx and appropriate /dev/pts/N in sequence. The result will be the following master `- slave 1 `- slave 2 both slave will have same master index but different file descriptors. Still inside the kernel pty parameters are same for both slaves. Thus only one slave parameters should be restored, there is no need to carry all parameters for every slave peer we've found. Not yet addressed problems: - At moment of restore the master peer might be already closed for any reason so to resolve such problem we need to open a fake master peer with proper index and hook a slave on it, then we close master peer. - Need to figure out how to deal with ttys which have some data in buffers not yet flushed, at moment this data will be simply lost during c/r - Need to restore control terminals - Need to fetch tty flags such as exclusive/packet-mode, this can't be done without kernel patching [ avagin@: - ideas on contol terminals restore - overall code redesign and simplification ] v4: - drop redundant pid from dump_chrdev - make sure optional fown is passed on regular ptys - add a comments about zeroifying termios - get rid of redundant empty line in files.c v5 (by avagin@): - complete rework of tty image format, now we have two files -- tty.img and tty-info.img. The idea behind to reduce data being stored. v6 (by xemul@): - packet mode should be set to true in image, until properly fetched from the kernel - verify image data on retrieval Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> CC: Andrey Vagin <avagin@openvz.org> Signed-off-by: Pavel Emelyanov <xemul@parallels.com> |
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| .. | ||
| atomic.h | ||
| bitops.h | ||
| compiler.h | ||
| crtools.h | ||
| eventfd.h | ||
| eventpoll.h | ||
| fifo.h | ||
| file-ids.h | ||
| files-reg.h | ||
| files.h | ||
| image.h | ||
| inet_diag.h | ||
| inotify.h | ||
| ipc_ns.h | ||
| kcmp-ids.h | ||
| libnetlink.h | ||
| linkage.h | ||
| list.h | ||
| lock.h | ||
| log-levels.h | ||
| log.h | ||
| memcpy_64.h | ||
| mount.h | ||
| namespaces.h | ||
| net.h | ||
| netfilter.h | ||
| packet_diag.h | ||
| parasite-syscall.h | ||
| parasite.h | ||
| pipes.h | ||
| proc_parse.h | ||
| processor-flags.h | ||
| protobuf.h | ||
| pstree.h | ||
| ptrace.h | ||
| rbtree.h | ||
| restorer-log.h | ||
| restorer.h | ||
| shmem.h | ||
| signalfd.h | ||
| sk-inet.h | ||
| sk-packet.h | ||
| sk-queue.h | ||
| sockets.h | ||
| syscall-types.h | ||
| syscall-x86-64.def | ||
| sysctl.h | ||
| tty.h | ||
| types.h | ||
| unix_diag.h | ||
| util-net.h | ||
| util.h | ||
| uts_ns.h | ||