X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=mount.c;h=728f3a25e4d49dcc40e79a7346338d6af0801b21;hp=f4a6d6f2469ce94ee17e7b9271759132b03f6722;hb=cc13a98b680087b24c1a319d10db98cd755a94d2;hpb=87f0e418cf2c58b3201d06a60e3696ec672d2662 diff --git a/mount.c b/mount.c index f4a6d6f24..728f3a25e 100644 --- a/mount.c +++ b/mount.c @@ -1,82 +1,464 @@ /*-*- Mode: C; c-basic-offset: 8 -*-*/ #include +#include +#include +#include +#include #include "unit.h" #include "mount.h" #include "load-fragment.h" -#include "load-fstab.h" #include "load-dropin.h" +#include "log.h" -static int mount_init(Unit *u) { - int r; +static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = { + [MOUNT_DEAD] = UNIT_INACTIVE, + [MOUNT_MOUNTING] = UNIT_ACTIVATING, + [MOUNT_MOUNTED] = UNIT_ACTIVE, + [MOUNT_UNMOUNTING] = UNIT_DEACTIVATING, + [MOUNT_MAINTAINANCE] = UNIT_INACTIVE, +}; + +static const char* const state_string_table[_MOUNT_STATE_MAX] = { + [MOUNT_DEAD] = "dead", + [MOUNT_MOUNTING] = "mounting", + [MOUNT_MOUNTED] = "mounted", + [MOUNT_UNMOUNTING] = "unmounting", + [MOUNT_MAINTAINANCE] = "maintainance" +}; + +static void mount_done(Unit *u) { Mount *m = MOUNT(u); assert(m); + free(m->what); + free(m->where); +} - /* Load a .mount file */ - if ((r = unit_load_fragment(u)) < 0 && errno != -ENOENT) - return r; +static void mount_set_state(Mount *m, MountState state) { + MountState old_state; + assert(m); - /* Load entry from /etc/fstab */ - if ((r = unit_load_fstab(u)) < 0) - return r; + if (state == m->state) + return; - /* Load drop-in directory data */ - if ((r = unit_load_dropin(u)) < 0) - return r; + old_state = m->state; + m->state = state; - return r; + log_debug("%s changed %s → %s", unit_id(UNIT(m)), state_string_table[old_state], state_string_table[state]); + + unit_notify(UNIT(m), state_translation_table[old_state], state_translation_table[state]); } -static void mount_done(Unit *u) { - Mount *d = MOUNT(u); +static int mount_coldplug(Unit *u) { + Mount *m = MOUNT(u); - assert(d); - free(d->path); -} + assert(m); + assert(m->state == MOUNT_DEAD); -static void mount_dump(Unit *u, FILE *f, const char *prefix) { + if (m->from_proc_self_mountinfo) + mount_set_state(m, MOUNT_MOUNTED); - static const char* const state_table[_MOUNT_STATE_MAX] = { - [MOUNT_DEAD] = "dead", - [MOUNT_MOUNTING] = "mounting", - [MOUNT_MOUNTED] = "mounted", - [MOUNT_UNMOUNTING] = "unmounting", - [MOUNT_MAINTAINANCE] = "maintainance" - }; + return 0; +} +static void mount_dump(Unit *u, FILE *f, const char *prefix) { Mount *s = MOUNT(u); assert(s); fprintf(f, "%sMount State: %s\n" - "%sPath: %s\n", - prefix, state_table[s->state], - prefix, s->path); + "%sWhere: %s\n" + "%sWhat: %s\n" + "%sFrom /etc/fstab: %s\n" + "%sFrom /proc/self/mountinfo: %s\n", + prefix, state_string_table[s->state], + prefix, s->where, + prefix, s->what, + prefix, yes_no(s->from_etc_fstab), + prefix, yes_no(s->from_proc_self_mountinfo)); } static UnitActiveState mount_active_state(Unit *u) { + assert(u); + + return state_translation_table[MOUNT(u)->state]; +} + +static void mount_shutdown(Manager *m) { + assert(m); + + if (m->proc_self_mountinfo) + fclose(m->proc_self_mountinfo); +} + +static int mount_add_node_links(Mount *m) { + Unit *device; + char *e; + int r; + + assert(m); + + /* Adds in links to the device that this node is based on */ + + if (!path_startswith(m->what, "/dev/")) + return 0; + + if (!(e = unit_name_escape_path("node-", m->what+1, ".device"))) + return -ENOMEM; + + r = manager_load_unit(UNIT(m)->meta.manager, e, &device); + free(e); + + if (r < 0) + return r; + + if ((r = unit_add_dependency(UNIT(m), UNIT_AFTER, device)) < 0) + return r; + + if ((r = unit_add_dependency(UNIT(m), UNIT_REQUIRES, device)) < 0) + return r; + + if ((r = unit_add_dependency(device, UNIT_WANTS, UNIT(m))) < 0) + return r; + + return 0; +} + +static int mount_add_path_links(Mount *m) { + Meta *other; + int r; + + /* Adds in link to other mount points, that might lie below or + * above us in the hierarchy */ + + LIST_FOREACH(units_per_type, other, UNIT(m)->meta.manager->units_per_type[UNIT_MOUNT]) { + Mount *n; + + n = (Mount*) other; + + if (n == m) + return 0; + + if (path_startswith(m->where, n->where)) { + + if ((r = unit_add_dependency(UNIT(m), UNIT_AFTER, (Unit*) other)) < 0) + return r; + + if ((r = unit_add_dependency(UNIT(m), UNIT_REQUIRES, (Unit*) other)) < 0) + return r; + + } else if (startswith(n->where, m->where)) { + + if ((r = unit_add_dependency(UNIT(m), UNIT_BEFORE, (Unit*) other)) < 0) + return r; + + if ((r = unit_add_dependency((Unit*) other, UNIT_REQUIRES, UNIT(m))) < 0) + return r; + } + } + + return 0; +} + +static int mount_add_one(Manager *m, const char *what, const char *where, bool live, bool set_flags) { + char *e; + int r; + Unit *u; + bool delete; + + assert(m); + assert(what); + assert(where); + + /* probably some kind of swap, which we don't cover for now */ + if (where[0] != '/') + return 0; + + if (streq(where, "/")) + e = strdup("rootfs.mount"); + else + e = unit_name_escape_path("fs-", where+1, ".mount"); + + if (!e) + return -ENOMEM; + + if (!(u = manager_get_unit(m, e))) { + delete = true; + + if (!(u = unit_new(m))) { + free(e); + return -ENOMEM; + } + + r = unit_add_name(u, e); + free(e); + + if (r < 0) + goto fail; + + if (!(MOUNT(u)->what = strdup(what)) || + !(MOUNT(u)->where = strdup(where))) { + r = -ENOMEM; + goto fail; + } + + if ((r = unit_set_description(u, where)) < 0) + goto fail; + + unit_add_to_load_queue(u); + } else { + delete = false; + free(e); + } + + if (set_flags) + MOUNT(u)->still_exists = true; + + if (live) { + if (set_flags) + MOUNT(u)->just_created = !MOUNT(u)->from_proc_self_mountinfo; + MOUNT(u)->from_proc_self_mountinfo = true; + } else { + if (set_flags) + MOUNT(u)->just_created = !MOUNT(u)->from_etc_fstab; + MOUNT(u)->from_etc_fstab = true; + } - static const UnitActiveState table[_MOUNT_STATE_MAX] = { - [MOUNT_DEAD] = UNIT_INACTIVE, - [MOUNT_MOUNTING] = UNIT_ACTIVATING, - [MOUNT_MOUNTED] = UNIT_ACTIVE, - [MOUNT_UNMOUNTING] = UNIT_DEACTIVATING, - [MOUNT_MAINTAINANCE] = UNIT_INACTIVE, - }; + if ((r = mount_add_node_links(MOUNT(u))) < 0) + goto fail; - return table[MOUNT(u)->state]; + if ((r = mount_add_path_links(MOUNT(u))) < 0) + goto fail; + + return 0; + +fail: + if (delete && u) + unit_free(u); + + return 0; +} + +static char *fstab_node_to_udev_node(char *p) { + char *dn, *t; + int r; + + /* FIXME: to follow udev's logic 100% we need to leave valid + * UTF8 chars unescaped */ + + if (startswith(p, "LABEL=")) { + + if (!(t = xescape(p+6, "/ "))) + return NULL; + + r = asprintf(&dn, "/dev/disk/by-label/%s", t); + free(t); + + if (r < 0) + return NULL; + + return dn; + } + + if (startswith(p, "UUID=")) { + + if (!(t = xescape(p+5, "/ "))) + return NULL; + + r = asprintf(&dn, "/dev/disk/by-uuid/%s", ascii_strlower(t)); + free(t); + + if (r < 0) + return NULL; + + return dn; + } + + return strdup(p); +} + +static int mount_load_etc_fstab(Manager *m, bool set_flags) { + FILE *f; + int r; + struct mntent* me; + + assert(m); + + errno = 0; + if (!(f = setmntent("/etc/fstab", "r"))) + return -errno; + + while ((me = getmntent(f))) { + char *where, *what; + + if (!(what = fstab_node_to_udev_node(me->mnt_fsname))) { + r = -ENOMEM; + goto finish; + } + + if (!(where = strdup(me->mnt_dir))) { + free(what); + r = -ENOMEM; + goto finish; + } + + if (what[0] == '/') + path_kill_slashes(what); + + if (where[0] == '/') + path_kill_slashes(where); + + r = mount_add_one(m, what, where, false, set_flags); + free(what); + free(where); + + if (r < 0) + goto finish; + } + + r = 0; +finish: + + endmntent(f); + return r; +} + +static int mount_load_proc_self_mountinfo(Manager *m, bool set_flags) { + int r; + + assert(m); + + rewind(m->proc_self_mountinfo); + + for (;;) { + int k; + char *device, *path, *d, *p; + + if ((k = fscanf(m->proc_self_mountinfo, + "%*s " /* (1) mount id */ + "%*s " /* (2) parent id */ + "%*s " /* (3) major:minor */ + "%*s " /* (4) root */ + "%ms " /* (5) mount point */ + "%*s" /* (6) mount options */ + "%*[^-]" /* (7) optional fields */ + "- " /* (8) seperator */ + "%*s " /* (9) file system type */ + "%ms" /* (10) mount source */ + "%*[^\n]", /* some rubbish at the end */ + &path, + &device)) != 2) { + + if (k == EOF) + break; + + return -EBADMSG; + } + + if (!(d = cunescape(device))) { + free(device); + free(path); + return -ENOMEM; + } + free(device); + + if (!(p = cunescape(path))) { + free(d); + free(path); + return -ENOMEM; + } + free(path); + + r = mount_add_one(m, d, p, true, set_flags); + free(d); + free(p); + + if (r < 0) + return r; + } + + return 0; +} + +static int mount_enumerate(Manager *m) { + int r; + struct epoll_event ev; + assert(m); + + if (!(m->proc_self_mountinfo = fopen("/proc/self/mountinfo", "r"))) + return -errno; + + m->mount_watch.type = WATCH_MOUNT; + m->mount_watch.fd = fileno(m->proc_self_mountinfo); + + zero(ev); + ev.events = EPOLLERR; + ev.data.ptr = &m->mount_watch; + + if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->mount_watch.fd, &ev) < 0) + return -errno; + + if ((r = mount_load_etc_fstab(m, false)) < 0) + goto fail; + + if ((r = mount_load_proc_self_mountinfo(m, false)) < 0) + goto fail; + + return 0; + +fail: + mount_shutdown(m); + return r; +} + +void mount_fd_event(Manager *m, int events) { + Meta *meta; + int r; + + assert(m); + assert(events == EPOLLERR); + + /* The manager calls this for every fd event happening on the + * /proc/self/mountinfo file, which informs us about mounting + * table changes */ + + if ((r = mount_load_proc_self_mountinfo(m, true)) < 0) { + log_error("Failed to reread /proc/self/mountinfo: %s", strerror(-errno)); + return; + } + + manager_dispatch_load_queue(m); + + LIST_FOREACH(units_per_type, meta, m->units_per_type[UNIT_MOUNT]) { + Mount *mount = (Mount*) meta; + + if (mount->just_created && mount->state == MOUNT_DEAD) + mount_set_state(mount, MOUNT_MOUNTED); + else if (!mount->still_exists && mount->state == MOUNT_MOUNTED) { + mount_set_state(mount, MOUNT_DEAD); + mount->from_proc_self_mountinfo = false; + } + + /* Clear the flags for later calls */ + mount->just_created = false; + mount->still_exists = false; + } } const UnitVTable mount_vtable = { .suffix = ".mount", - .init = mount_init, + .init = unit_load_fragment_and_dropin, .done = mount_done, + .coldplug = mount_coldplug, .dump = mount_dump, .active_state = mount_active_state, + + .enumerate = mount_enumerate, + .shutdown = mount_shutdown };