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/*
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* QEMU live migration via generic fd
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*
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* Copyright Red Hat, Inc. 2009
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*
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* Authors:
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* Chris Lalancette <clalance@redhat.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*
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* Contributions after 2012-01-13 are licensed under the terms of the
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* GNU GPL, version 2 or (at your option) any later version.
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*/
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#include "qemu-common.h" |
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#include "qemu_socket.h" |
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#include "migration.h" |
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#include "monitor.h" |
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#include "qemu-char.h" |
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#include "buffered_file.h" |
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#include "block.h" |
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#include "qemu_socket.h" |
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//#define DEBUG_MIGRATION_FD
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#ifdef DEBUG_MIGRATION_FD
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#define DPRINTF(fmt, ...) \
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do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0) |
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#else
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#define DPRINTF(fmt, ...) \
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do { } while (0) |
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#endif
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static int fd_errno(MigrationState *s) |
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{ |
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return errno;
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} |
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static int fd_write(MigrationState *s, const void * buf, size_t size) |
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{ |
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return write(s->fd, buf, size);
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} |
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static int fd_close(MigrationState *s) |
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{ |
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struct stat st;
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int ret;
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DPRINTF("fd_close\n");
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if (s->fd != -1) { |
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ret = fstat(s->fd, &st); |
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if (ret == 0 && S_ISREG(st.st_mode)) { |
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/*
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* If the file handle is a regular file make sure the
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* data is flushed to disk before signaling success.
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*/
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ret = fsync(s->fd); |
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if (ret != 0) { |
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ret = -errno; |
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perror("migration-fd: fsync");
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return ret;
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} |
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} |
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ret = close(s->fd); |
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s->fd = -1;
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if (ret != 0) { |
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ret = -errno; |
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perror("migration-fd: close");
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return ret;
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} |
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} |
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return 0; |
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} |
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int fd_start_outgoing_migration(MigrationState *s, const char *fdname) |
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{ |
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s->fd = monitor_get_fd(cur_mon, fdname); |
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if (s->fd == -1) { |
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DPRINTF("fd_migration: invalid file descriptor identifier\n");
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goto err_after_get_fd;
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} |
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if (fcntl(s->fd, F_SETFL, O_NONBLOCK) == -1) { |
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DPRINTF("Unable to set nonblocking mode on file descriptor\n");
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goto err_after_open;
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} |
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s->get_error = fd_errno; |
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s->write = fd_write; |
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s->close = fd_close; |
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migrate_fd_connect(s); |
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return 0; |
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err_after_open:
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close(s->fd); |
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err_after_get_fd:
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return -1; |
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} |
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static void fd_accept_incoming_migration(void *opaque) |
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{ |
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QEMUFile *f = opaque; |
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process_incoming_migration(f); |
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qemu_set_fd_handler2(qemu_stdio_fd(f), NULL, NULL, NULL, NULL); |
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qemu_fclose(f); |
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} |
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int fd_start_incoming_migration(const char *infd) |
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{ |
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int fd;
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QEMUFile *f; |
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DPRINTF("Attempting to start an incoming migration via fd\n");
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fd = strtol(infd, NULL, 0); |
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f = qemu_fdopen(fd, "rb");
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if(f == NULL) { |
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DPRINTF("Unable to apply qemu wrapper to file descriptor\n");
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return -errno;
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} |
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qemu_set_fd_handler2(fd, NULL, fd_accept_incoming_migration, NULL, f); |
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return 0; |
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} |