From d21ff39aabd6f081953bff55e531c67a14f190df Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Wed, 25 Dec 2013 16:54:36 +0400 Subject: [PATCH] mount: Dump external bind-mounts with plugins External bind mounts are those with source sitting outside of the current FS view. Such are detected in validate_mounts(), so we just go ahead and call plugins. The plugin is provided with the mountpoint to decide whether it's his or not (what else does the guy need?) and an ID with this it can identify the mountpoint in /proc. The same ID will be used at restore time to find the needed restore info. Signed-off-by: Pavel Emelyanov --- include/criu-plugin.h | 2 ++ include/plugin.h | 2 ++ include/proc_parse.h | 1 + mount.c | 31 +++++++++++++++++++++++-------- plugin.c | 9 +++++++++ protobuf/mnt.proto | 2 ++ 6 files changed, 39 insertions(+), 8 deletions(-) diff --git a/include/criu-plugin.h b/include/criu-plugin.h index cf6a2c535..a76073045 100644 --- a/include/criu-plugin.h +++ b/include/criu-plugin.h @@ -32,6 +32,8 @@ typedef int (cr_plugin_restore_unix_sk_t)(int id); typedef int (cr_plugin_dump_file_t)(int fd, int id); typedef int (cr_plugin_restore_file_t)(int id); +typedef int (cr_plugin_dump_ext_mount_t)(char *mountpoint, int id); + /* Public API */ extern int criu_get_image_dir(void); diff --git a/include/plugin.h b/include/plugin.h index 6c8ab829d..9a077d95c 100644 --- a/include/plugin.h +++ b/include/plugin.h @@ -14,4 +14,6 @@ int cr_plugin_restore_unix_sk(int id); int cr_plugin_dump_file(int fd, int id); int cr_plugin_restore_file(int id); +int cr_plugin_dump_ext_mount(char *mountpoint, int id); + #endif diff --git a/include/proc_parse.h b/include/proc_parse.h index 9af46f6a0..ef203156e 100644 --- a/include/proc_parse.h +++ b/include/proc_parse.h @@ -112,6 +112,7 @@ struct mount_info { char *source; char *options; bool mounted; + bool need_plugin; struct mount_info *next; /* tree linkage */ diff --git a/mount.c b/mount.c index f07206a84..67797fa0d 100644 --- a/mount.c +++ b/mount.c @@ -17,6 +17,7 @@ #include "util.h" #include "util-pie.h" #include "log.h" +#include "plugin.h" #include "mount.h" #include "pstree.h" #include "proc_parse.h" @@ -42,7 +43,7 @@ static DIR *open_mountpoint(struct mount_info *pm); static int close_mountpoint(DIR *dfd); static struct mount_info *mnt_build_tree(struct mount_info *list); -static int validate_mounts(struct mount_info *info); +static int validate_mounts(struct mount_info *info, bool call_plugins); static inline int is_root(char *p) { @@ -294,7 +295,7 @@ static void mnt_tree_show(struct mount_info *tree, int off) pr_info("%*s<--\n", off, ""); } -static int validate_mounts(struct mount_info *info) +static int validate_mounts(struct mount_info *info, bool call_plugins) { struct mount_info *m, *t; @@ -325,9 +326,19 @@ static int validate_mounts(struct mount_info *info) break; } if (&t->mnt_bind == &m->mnt_bind) { - pr_err("%d:%s doesn't have a proper root mount\n", - m->mnt_id, m->mountpoint); - return -1; + int ret = -ENOTSUP; + + if (call_plugins) { + ret = cr_plugin_dump_ext_mount(m->mountpoint, m->mnt_id); + if (ret == 0) + m->need_plugin = true; + } + if (ret < 0) { + if (ret == -ENOTSUP) + pr_err("%d:%s doesn't have a proper root mount\n", + m->mnt_id, m->mountpoint); + return -1; + } } } @@ -716,7 +727,7 @@ static int dump_one_mountpoint(struct mount_info *pm, int fd) return -1; } - if (pm->fstype->dump && pm->fstype->dump(pm)) + if (!pm->need_plugin && pm->fstype->dump && pm->fstype->dump(pm)) return -1; me.mnt_id = pm->mnt_id; @@ -731,6 +742,10 @@ static int dump_one_mountpoint(struct mount_info *pm, int fd) me.has_shared_id = true; me.master_id = pm->master_id; me.has_master_id = true; + if (pm->need_plugin) { + me.has_with_plugin = true; + me.with_plugin = true; + } if (pb_write_one(fd, &me, PB_MNT)) return -1; @@ -756,7 +771,7 @@ int dump_mnt_ns(int ns_pid, int ns_id) if (mnt_build_tree(pm) == NULL) goto err; - if (validate_mounts(pm)) + if (validate_mounts(pm, true)) goto err; pr_info("Dumping mountpoints\n"); @@ -1297,7 +1312,7 @@ static int populate_mnt_ns(int ns_pid, struct mount_info *mis) if (!pms) return -1; - if (validate_mounts(pms)) + if (validate_mounts(pms, false)) return -1; mntinfo_tree = pms; diff --git a/plugin.c b/plugin.c index 222a2f598..434926546 100644 --- a/plugin.c +++ b/plugin.c @@ -19,6 +19,7 @@ struct cr_plugin_entry { cr_plugin_restore_unix_sk_t *cr_plugin_restore_unix_sk; cr_plugin_dump_file_t *cr_plugin_dump_file; cr_plugin_restore_file_t *cr_plugin_restore_file; + cr_plugin_dump_ext_mount_t *cr_plugin_dump_ext_mount; }; struct cr_plugin_entry *next; @@ -31,6 +32,7 @@ struct cr_plugins { struct cr_plugin_entry *cr_plugin_restore_unix_sk; struct cr_plugin_entry *cr_plugin_dump_file; struct cr_plugin_entry *cr_plugin_restore_file; + struct cr_plugin_entry *cr_plugin_dump_ext_mount; }; struct cr_plugins cr_plugins; @@ -87,6 +89,11 @@ int cr_plugin_restore_file(int id) return run_plugin_funcs(cr_plugin_restore_file, id); } +int cr_plugin_dump_ext_mount(char *mountpoint, int id) +{ + return run_plugin_funcs(cr_plugin_dump_ext_mount, mountpoint, id); +} + static int cr_lib_load(char *path) { struct cr_plugin_entry *ce; @@ -106,6 +113,8 @@ static int cr_lib_load(char *path) add_plugin_func(cr_plugin_dump_file); add_plugin_func(cr_plugin_restore_file); + add_plugin_func(cr_plugin_dump_ext_mount); + ce = NULL; f_fini = dlsym(h, "cr_plugin_fini"); if (f_fini) { diff --git a/protobuf/mnt.proto b/protobuf/mnt.proto index ea1ad3c21..ab85de7ec 100644 --- a/protobuf/mnt.proto +++ b/protobuf/mnt.proto @@ -23,4 +23,6 @@ message mnt_entry { optional uint32 shared_id = 10; optional uint32 master_id = 11; + + optional bool with_plugin = 12; }