[CRIU] [PATCH 11/15] files: pass a file descriptor on an fdinfo image instead of cr_fdset
Pavel Emelyanov
xemul at parallels.com
Thu Jan 10 06:28:31 EST 2013
On 01/10/2013 02:00 PM, Andrey Vagin wrote:
> Because only fdinfo is used for dumping files. fdinfo will be detached
> from pid and will be dumped per id, because a few processes can share
> one fd table.
Plz rephrase this. I can't parse this text. What is fdinfo here? What does
"will be detached from pid" means? Why number of processes sharing one fdt
matters?
> Signed-off-by: Andrey Vagin <avagin at openvz.org>
> ---
> cr-dump.c | 36 ++++++++++++++++++------------------
> eventfd.c | 4 ++--
> eventpoll.c | 4 ++--
> fifo.c | 4 ++--
> files-reg.c | 4 ++--
> include/eventfd.h | 2 +-
> include/eventpoll.h | 2 +-
> include/fifo.h | 2 +-
> include/files-reg.h | 2 +-
> include/files.h | 2 +-
> include/inotify.h | 2 +-
> include/pipes.h | 2 +-
> include/signalfd.h | 2 +-
> include/sk-packet.h | 2 +-
> include/sockets.h | 8 ++++----
> include/tty.h | 2 +-
> inotify.c | 4 ++--
> pipes.c | 4 ++--
> signalfd.c | 4 ++--
> sk-inet.c | 8 ++++----
> sk-packet.c | 4 ++--
> sk-unix.c | 4 ++--
> sockets.c | 10 +++++-----
> tty.c | 4 ++--
> 24 files changed, 61 insertions(+), 61 deletions(-)
>
> diff --git a/cr-dump.c b/cr-dump.c
> index 45dfe70..a348282 100644
> --- a/cr-dump.c
> +++ b/cr-dump.c
> @@ -197,7 +197,7 @@ static u32 make_gen_id(const struct fd_parms *p)
> }
>
> int do_dump_gen_file(struct fd_parms *p, int lfd,
> - const struct fdtype_ops *ops, const struct cr_fdset *cr_fdset)
> + const struct fdtype_ops *ops, const int fdinfo)
> {
> FdinfoEntry e = FDINFO_ENTRY__INIT;
> int ret = -1;
> @@ -217,7 +217,7 @@ int do_dump_gen_file(struct fd_parms *p, int lfd,
> pr_info("fdinfo: type: 0x%2x flags: %#o/%#o pos: 0x%8lx fd: %d\n",
> ops->type, p->flags, (int)p->fd_flags, p->pos, p->fd);
>
> - return pb_write_one(fdset_fd(cr_fdset, CR_FD_FDINFO), &e, PB_FDINFO);
> + return pb_write_one(fdinfo, &e, PB_FDINFO);
> }
>
> static int dump_task_exe_link(pid_t pid, MmEntry *mm)
> @@ -286,17 +286,17 @@ static int dump_unsupp_fd(const struct fd_parms *p)
> return -1;
> }
>
> -static int dump_chrdev(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +static int dump_chrdev(struct fd_parms *p, int lfd, const int fdinfo)
> {
> int maj = major(p->stat.st_rdev);
>
> switch (maj) {
> case MEM_MAJOR:
> - return dump_reg_file(p, lfd, set);
> + return dump_reg_file(p, lfd, fdinfo);
> case TTYAUX_MAJOR:
> case UNIX98_PTY_MASTER_MAJOR ... (UNIX98_PTY_MASTER_MAJOR + UNIX98_PTY_MAJOR_COUNT - 1):
> case UNIX98_PTY_SLAVE_MAJOR:
> - return dump_tty(p, lfd, set);
> + return dump_tty(p, lfd, fdinfo);
> }
>
> return dump_unsupp_fd(p);
> @@ -307,7 +307,7 @@ static int dump_chrdev(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> #endif
>
> static int dump_one_file(struct parasite_ctl *ctl, int fd, int lfd, struct fd_opts *opts,
> - const struct cr_fdset *cr_fdset)
> + const int fdinfo)
> {
> struct fd_parms p;
> struct statfs statfs;
> @@ -318,10 +318,10 @@ static int dump_one_file(struct parasite_ctl *ctl, int fd, int lfd, struct fd_op
> }
>
> if (S_ISSOCK(p.stat.st_mode))
> - return dump_socket(&p, lfd, cr_fdset);
> + return dump_socket(&p, lfd, fdinfo);
>
> if (S_ISCHR(p.stat.st_mode))
> - return dump_chrdev(&p, lfd, cr_fdset);
> + return dump_chrdev(&p, lfd, fdinfo);
>
> if (fstatfs(lfd, &statfs)) {
> pr_perror("Can't obtain statfs on fd %d\n", fd);
> @@ -330,31 +330,31 @@ static int dump_one_file(struct parasite_ctl *ctl, int fd, int lfd, struct fd_op
>
> if (is_anon_inode(&statfs)) {
> if (is_eventfd_link(lfd))
> - return dump_eventfd(&p, lfd, cr_fdset);
> + return dump_eventfd(&p, lfd, fdinfo);
> else if (is_eventpoll_link(lfd))
> - return dump_eventpoll(&p, lfd, cr_fdset);
> + return dump_eventpoll(&p, lfd, fdinfo);
> else if (is_inotify_link(lfd))
> - return dump_inotify(&p, lfd, cr_fdset);
> + return dump_inotify(&p, lfd, fdinfo);
> else if (is_signalfd_link(lfd))
> - return dump_signalfd(&p, lfd, cr_fdset);
> + return dump_signalfd(&p, lfd, fdinfo);
> else
> return dump_unsupp_fd(&p);
> }
>
> if (S_ISREG(p.stat.st_mode) || S_ISDIR(p.stat.st_mode))
> - return dump_reg_file(&p, lfd, cr_fdset);
> + return dump_reg_file(&p, lfd, fdinfo);
>
> if (S_ISFIFO(p.stat.st_mode)) {
> if (statfs.f_type == PIPEFS_MAGIC)
> - return dump_pipe(&p, lfd, cr_fdset);
> + return dump_pipe(&p, lfd, fdinfo);
> else
> - return dump_fifo(&p, lfd, cr_fdset);
> + return dump_fifo(&p, lfd, fdinfo);
> }
>
> return dump_unsupp_fd(&p);
> }
>
> -static int dump_task_files_seized(struct parasite_ctl *ctl, const struct cr_fdset *cr_fdset,
> +static int dump_task_files_seized(struct parasite_ctl *ctl, const int fdinfo,
> struct parasite_drain_fd *dfds)
> {
> int *lfds;
> @@ -378,7 +378,7 @@ static int dump_task_files_seized(struct parasite_ctl *ctl, const struct cr_fdse
> goto err2;
>
> for (i = 0; i < dfds->nr_fds; i++) {
> - ret = dump_one_file(ctl, dfds->fds[i], lfds[i], opts + i, cr_fdset);
> + ret = dump_one_file(ctl, dfds->fds[i], lfds[i], opts + i, fdinfo);
> close(lfds[i]);
> if (ret)
> goto err2;
> @@ -1419,7 +1419,7 @@ static int dump_one_task(struct pstree_item *item)
> if (!cr_fdset)
> goto err_cure;
>
> - ret = dump_task_files_seized(parasite_ctl, cr_fdset, dfds);
> + ret = dump_task_files_seized(parasite_ctl, fdset_fd(cr_fdset, CR_FD_FDINFO), dfds);
> if (ret) {
> pr_err("Dump files (pid: %d) failed with %d\n", pid, ret);
> goto err_cure;
> diff --git a/eventfd.c b/eventfd.c
> index 1e48af2..1a8fca3 100644
> --- a/eventfd.c
> +++ b/eventfd.c
> @@ -85,9 +85,9 @@ static const struct fdtype_ops eventfd_ops = {
> .dump = dump_one_eventfd,
> };
>
> -int dump_eventfd(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_eventfd(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &eventfd_ops, set);
> + return do_dump_gen_file(p, lfd, &eventfd_ops, fdinfo);
> }
>
> static int eventfd_open(struct file_desc *d)
> diff --git a/eventpoll.c b/eventpoll.c
> index ccce771..3c77bc6 100644
> --- a/eventpoll.c
> +++ b/eventpoll.c
> @@ -97,9 +97,9 @@ static const struct fdtype_ops eventpoll_ops = {
> .dump = dump_one_eventpoll,
> };
>
> -int dump_eventpoll(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_eventpoll(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &eventpoll_ops, set);
> + return do_dump_gen_file(p, lfd, &eventpoll_ops, fdinfo);
> }
>
> static int eventpoll_open(struct file_desc *d)
> diff --git a/fifo.c b/fifo.c
> index edc8a23..ea32bcf 100644
> --- a/fifo.c
> +++ b/fifo.c
> @@ -68,9 +68,9 @@ static const struct fdtype_ops fifo_ops = {
> .dump = dump_one_fifo,
> };
>
> -int dump_fifo(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_fifo(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &fifo_ops, set);
> + return do_dump_gen_file(p, lfd, &fifo_ops, fdinfo);
> }
>
> static struct pipe_data_rst *pd_hash_fifo[PIPE_DATA_HASH_SIZE];
> diff --git a/files-reg.c b/files-reg.c
> index cf4fd71..66dfadd 100644
> --- a/files-reg.c
> +++ b/files-reg.c
> @@ -469,9 +469,9 @@ static const struct fdtype_ops regfile_ops = {
> };
>
> int dump_reg_file(struct fd_parms *p, int lfd,
> - const struct cr_fdset *cr_fdset)
> + const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, ®file_ops, cr_fdset);
> + return do_dump_gen_file(p, lfd, ®file_ops, fdinfo);
> }
>
> static int open_path(struct file_desc *d,
> diff --git a/include/eventfd.h b/include/eventfd.h
> index 7515410..aed8ba4 100644
> --- a/include/eventfd.h
> +++ b/include/eventfd.h
> @@ -10,7 +10,7 @@
> #include "crtools.h"
>
> extern int is_eventfd_link(int lfd);
> -extern int dump_eventfd(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> +extern int dump_eventfd(struct fd_parms *p, int lfd, const int fdinfo);
> extern int collect_eventfd(void);
> extern void show_eventfds(int fd, struct cr_options *o);
>
> diff --git a/include/eventpoll.h b/include/eventpoll.h
> index a2f5f11..03a4cc1 100644
> --- a/include/eventpoll.h
> +++ b/include/eventpoll.h
> @@ -10,7 +10,7 @@
> #include "crtools.h"
>
> extern int is_eventpoll_link(int lfd);
> -extern int dump_eventpoll(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> +extern int dump_eventpoll(struct fd_parms *p, int lfd, const int fdinfo);
> extern int collect_eventpoll(void);
> extern void show_eventpoll(int fd, struct cr_options *o);
> extern void show_eventpoll_tfd(int fd, struct cr_options *o);
> diff --git a/include/fifo.h b/include/fifo.h
> index bfa9612..dc5aecf 100644
> --- a/include/fifo.h
> +++ b/include/fifo.h
> @@ -4,7 +4,7 @@
> struct fd_parms;
> struct cr_fdset;
>
> -extern int dump_fifo(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> +extern int dump_fifo(struct fd_parms *p, int lfd, const int fdinfo);
> extern int collect_fifo(void);
>
> #endif /* __CR_FIFO_H__ */
> diff --git a/include/files-reg.h b/include/files-reg.h
> index 51022e7..b9aeff4 100644
> --- a/include/files-reg.h
> +++ b/include/files-reg.h
> @@ -30,7 +30,7 @@ extern int collect_reg_files(void);
>
> extern int prepare_shared_reg_files(void);
>
> -extern int dump_reg_file(struct fd_parms *p, int lfd, const struct cr_fdset *cr_fdset);
> +extern int dump_reg_file(struct fd_parms *p, int lfd, const int fdinfo);
> extern int dump_one_reg_file(int lfd, u32 id, const struct fd_parms *p);
>
> extern struct file_remap *lookup_ghost_remap(u32 dev, u32 ino);
> diff --git a/include/files.h b/include/files.h
> index b33ae17..9d829f2 100644
> --- a/include/files.h
> +++ b/include/files.h
> @@ -74,7 +74,7 @@ struct fdtype_ops {
>
> extern int do_dump_gen_file(struct fd_parms *p, int lfd,
> const struct fdtype_ops *ops,
> - const struct cr_fdset *cr_fdset);
> + const int fdinfo);
>
> extern void file_desc_add(struct file_desc *d, u32 id, struct file_desc_ops *ops);
> extern struct fdinfo_list_entry *file_master(struct file_desc *d);
> diff --git a/include/inotify.h b/include/inotify.h
> index d45b2bc..8daf66a 100644
> --- a/include/inotify.h
> +++ b/include/inotify.h
> @@ -10,7 +10,7 @@
> #include "crtools.h"
>
> extern int is_inotify_link(int lfd);
> -extern int dump_inotify(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> +extern int dump_inotify(struct fd_parms *p, int lfd, const int fdinfo);
> extern int collect_inotify(void);
> extern void show_inotify_wd(int fd_inotify_wd, struct cr_options *o);
> extern void show_inotify(int fd_inotify, struct cr_options *o);
> diff --git a/include/pipes.h b/include/pipes.h
> index d31d48e..38855e4 100644
> --- a/include/pipes.h
> +++ b/include/pipes.h
> @@ -6,7 +6,7 @@
> extern int collect_pipes(void);
> extern void mark_pipe_master(void);
> int dump_pipe(struct fd_parms *p, int lfd,
> - const struct cr_fdset *cr_fdset);
> + const int fdinfo);
>
> static inline u32 pipe_id(const struct fd_parms *p)
> {
> diff --git a/include/signalfd.h b/include/signalfd.h
> index 2ac8ff5..c5d6978 100644
> --- a/include/signalfd.h
> +++ b/include/signalfd.h
> @@ -5,7 +5,7 @@ struct cr_fdset;
> struct fd_parms;
> struct cr_options;
> extern int is_signalfd_link(int lfd);
> -extern int dump_signalfd(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> +extern int dump_signalfd(struct fd_parms *p, int lfd, const int fdinfo);
> extern void show_signalfd(int fd, struct cr_options *o);
> extern int collect_signalfd(void);
>
> diff --git a/include/sk-packet.h b/include/sk-packet.h
> index a998c33..675c932 100644
> --- a/include/sk-packet.h
> +++ b/include/sk-packet.h
> @@ -10,7 +10,7 @@ struct fd_parms;
> struct cr_options;
> struct vma_area;
>
> -int dump_one_packet_sk(struct fd_parms *p, int lfd, const struct cr_fdset *fds);
> +int dump_one_packet_sk(struct fd_parms *p, int lfd, const int fdinfo);
> int collect_packet_sockets(void);
> void show_packetsk(int fd, struct cr_options *);
>
> diff --git a/include/sockets.h b/include/sockets.h
> index ed3ac09..22ffd9b 100644
> --- a/include/sockets.h
> +++ b/include/sockets.h
> @@ -26,7 +26,7 @@ struct socket_desc {
> int already_dumped;
> };
>
> -extern int dump_socket(struct fd_parms *p, int lfd, const struct cr_fdset *cr_fdset);
> +extern int dump_socket(struct fd_parms *p, int lfd, const int fdinfo);
> extern int dump_socket_opts(int sk, SkOptsEntry *soe);
> extern int restore_socket_opts(int sk, SkOptsEntry *soe);
> extern void release_skopts(SkOptsEntry *);
> @@ -50,9 +50,9 @@ extern char *skstate2s(u32 state);
>
> extern struct socket_desc *lookup_socket(int ino, int family);
>
> -extern int dump_one_inet(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> -extern int dump_one_inet6(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> -extern int dump_one_unix(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> +extern int dump_one_inet(struct fd_parms *p, int lfd, const int fdinfo);
> +extern int dump_one_inet6(struct fd_parms *p, int lfd, const int fdinfo);
> +extern int dump_one_unix(struct fd_parms *p, int lfd, const int fdinfo);
>
> extern int inet_collect_one(struct nlmsghdr *h, int family, int type, int proto);
> extern int unix_receive_one(struct nlmsghdr *h, void *);
> diff --git a/include/tty.h b/include/tty.h
> index bf370ab..e7e653a 100644
> --- a/include/tty.h
> +++ b/include/tty.h
> @@ -13,7 +13,7 @@
> #endif
> #define PTS_FMT "/dev/pts/%d"
>
> -extern int dump_tty(struct fd_parms *p, int lfd, const struct cr_fdset *set);
> +extern int dump_tty(struct fd_parms *p, int lfd, const int fdinfo);
> extern int dump_verify_tty_sids(void);
> extern int collect_tty(void);
> extern int prepare_shared_tty(void);
> diff --git a/inotify.c b/inotify.c
> index c7f7365..3d574ba 100644
> --- a/inotify.c
> +++ b/inotify.c
> @@ -105,9 +105,9 @@ static const struct fdtype_ops inotify_ops = {
> .dump = dump_one_inotify,
> };
>
> -int dump_inotify(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_inotify(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &inotify_ops, set);
> + return do_dump_gen_file(p, lfd, &inotify_ops, fdinfo);
> }
>
> static int restore_one_inotify(int inotify_fd, struct inotify_wd_info *info)
> diff --git a/pipes.c b/pipes.c
> index 6542ec6..e595a3a 100644
> --- a/pipes.c
> +++ b/pipes.c
> @@ -440,7 +440,7 @@ static const struct fdtype_ops pipe_ops = {
> .dump = dump_one_pipe,
> };
>
> -int dump_pipe(struct fd_parms *p, int lfd, const struct cr_fdset *cr_fdset)
> +int dump_pipe(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &pipe_ops, cr_fdset);
> + return do_dump_gen_file(p, lfd, &pipe_ops, fdinfo);
> }
> diff --git a/signalfd.c b/signalfd.c
> index 91c14d6..c8dc77f 100644
> --- a/signalfd.c
> +++ b/signalfd.c
> @@ -65,9 +65,9 @@ static const struct fdtype_ops signalfd_ops = {
> .dump = dump_one_signalfd,
> };
>
> -int dump_signalfd(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_signalfd(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &signalfd_ops, set);
> + return do_dump_gen_file(p, lfd, &signalfd_ops, fdinfo);
> }
>
> static void sigset_fill(sigset_t *to, unsigned long long from)
> diff --git a/sk-inet.c b/sk-inet.c
> index 25581ba..b411c28 100644
> --- a/sk-inet.c
> +++ b/sk-inet.c
> @@ -315,9 +315,9 @@ static const struct fdtype_ops inet_dump_ops = {
> .dump = dump_one_inet_fd,
> };
>
> -int dump_one_inet(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_one_inet(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &inet_dump_ops, set);
> + return do_dump_gen_file(p, lfd, &inet_dump_ops, fdinfo);
> }
>
> static int dump_one_inet6_fd(int lfd, u32 id, const struct fd_parms *p)
> @@ -330,9 +330,9 @@ static const struct fdtype_ops inet6_dump_ops = {
> .dump = dump_one_inet6_fd,
> };
>
> -int dump_one_inet6(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_one_inet6(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &inet6_dump_ops, set);
> + return do_dump_gen_file(p, lfd, &inet6_dump_ops, fdinfo);
> }
>
> int inet_collect_one(struct nlmsghdr *h, int family, int type, int proto)
> diff --git a/sk-packet.c b/sk-packet.c
> index 0e85d36..db938dd 100644
> --- a/sk-packet.c
> +++ b/sk-packet.c
> @@ -208,9 +208,9 @@ static const struct fdtype_ops packet_dump_ops = {
> .dump = dump_one_packet_fd,
> };
>
> -int dump_one_packet_sk(struct fd_parms *p, int lfd, const struct cr_fdset *fds)
> +int dump_one_packet_sk(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &packet_dump_ops, fds);
> + return do_dump_gen_file(p, lfd, &packet_dump_ops, fdinfo);
> }
>
> int dump_socket_map(struct vma_area *vma)
> diff --git a/sk-unix.c b/sk-unix.c
> index c6ec844..ce37dbc 100644
> --- a/sk-unix.c
> +++ b/sk-unix.c
> @@ -242,9 +242,9 @@ static const struct fdtype_ops unix_dump_ops = {
> .dump = dump_one_unix_fd,
> };
>
> -int dump_one_unix(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_one_unix(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &unix_dump_ops, set);
> + return do_dump_gen_file(p, lfd, &unix_dump_ops, fdinfo);
> }
>
> static int unix_collect_one(const struct unix_diag_msg *m,
> diff --git a/sockets.c b/sockets.c
> index 3d617d8..175d165 100644
> --- a/sockets.c
> +++ b/sockets.c
> @@ -366,7 +366,7 @@ void release_skopts(SkOptsEntry *soe)
> xfree(soe->so_bound_dev);
> }
>
> -int dump_socket(struct fd_parms *p, int lfd, const struct cr_fdset *cr_fdset)
> +int dump_socket(struct fd_parms *p, int lfd, const int fdinfo)
> {
> int family;
>
> @@ -375,13 +375,13 @@ int dump_socket(struct fd_parms *p, int lfd, const struct cr_fdset *cr_fdset)
>
> switch (family) {
> case AF_UNIX:
> - return dump_one_unix(p, lfd, cr_fdset);
> + return dump_one_unix(p, lfd, fdinfo);
> case AF_INET:
> - return dump_one_inet(p, lfd, cr_fdset);
> + return dump_one_inet(p, lfd, fdinfo);
> case AF_INET6:
> - return dump_one_inet6(p, lfd, cr_fdset);
> + return dump_one_inet6(p, lfd, fdinfo);
> case AF_PACKET:
> - return dump_one_packet_sk(p, lfd, cr_fdset);
> + return dump_one_packet_sk(p, lfd, fdinfo);
> default:
> pr_err("BUG! Unknown socket collected\n");
> break;
> diff --git a/tty.c b/tty.c
> index 3d9c369..d32b3f7 100644
> --- a/tty.c
> +++ b/tty.c
> @@ -1186,9 +1186,9 @@ static const struct fdtype_ops tty_ops = {
> .dump = dump_one_pty,
> };
>
> -int dump_tty(struct fd_parms *p, int lfd, const struct cr_fdset *set)
> +int dump_tty(struct fd_parms *p, int lfd, const int fdinfo)
> {
> - return do_dump_gen_file(p, lfd, &tty_ops, set);
> + return do_dump_gen_file(p, lfd, &tty_ops, fdinfo);
> }
>
> int tty_prep_fds(void)
>
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