diff options
Diffstat (limited to 'src/shared/reboot-util.c')
| -rw-r--r-- | src/shared/reboot-util.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/src/shared/reboot-util.c b/src/shared/reboot-util.c new file mode 100644 index 0000000..62ff697 --- /dev/null +++ b/src/shared/reboot-util.c @@ -0,0 +1,196 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <errno.h> +#include <stdint.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <unistd.h> + +#if HAVE_XENCTRL +#define __XEN_INTERFACE_VERSION__ 0x00040900 +#include <xen/xen.h> +#include <xen/kexec.h> +#include <xen/sys/privcmd.h> +#endif + +#include "alloc-util.h" +#include "errno-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "log.h" +#include "proc-cmdline.h" +#include "raw-reboot.h" +#include "reboot-util.h" +#include "string-util.h" +#include "umask-util.h" +#include "virt.h" + +int update_reboot_parameter_and_warn(const char *parameter, bool keep) { + int r; + + if (isempty(parameter)) { + if (keep) + return 0; + + if (unlink("/run/systemd/reboot-param") < 0) { + if (errno == ENOENT) + return 0; + + return log_warning_errno(errno, "Failed to unlink reboot parameter file: %m"); + } + + return 0; + } + + WITH_UMASK(0022) { + r = write_string_file("/run/systemd/reboot-param", parameter, + WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC); + if (r < 0) + return log_warning_errno(r, "Failed to write reboot parameter file: %m"); + } + + return 0; +} + +int read_reboot_parameter(char **parameter) { + int r; + + assert(parameter); + + r = read_one_line_file("/run/systemd/reboot-param", parameter); + if (r < 0 && r != -ENOENT) + return log_debug_errno(r, "Failed to read /run/systemd/reboot-param: %m"); + + return 0; +} + +int reboot_with_parameter(RebootFlags flags) { + int r; + + /* Reboots the system with a parameter that is read from /run/systemd/reboot-param. Returns 0 if + * REBOOT_DRY_RUN was set and the actual reboot operation was hence skipped. If REBOOT_FALLBACK is + * set and the reboot with parameter doesn't work out a fallback to classic reboot() is attempted. If + * REBOOT_FALLBACK is not set, 0 is returned instead, which should be considered indication for the + * caller to fall back to reboot() on its own, or somehow else deal with this. If REBOOT_LOG is + * specified will log about what it is going to do, as well as all errors. */ + + if (detect_container() == 0) { + _cleanup_free_ char *parameter = NULL; + + r = read_one_line_file("/run/systemd/reboot-param", ¶meter); + if (r < 0 && r != -ENOENT) + log_full_errno(flags & REBOOT_LOG ? LOG_WARNING : LOG_DEBUG, r, + "Failed to read reboot parameter file, ignoring: %m"); + + if (!isempty(parameter)) { + log_full(flags & REBOOT_LOG ? LOG_INFO : LOG_DEBUG, + "Rebooting with argument '%s'.", parameter); + + if (flags & REBOOT_DRY_RUN) + return 0; + + (void) raw_reboot(LINUX_REBOOT_CMD_RESTART2, parameter); + + log_full_errno(flags & REBOOT_LOG ? LOG_WARNING : LOG_DEBUG, errno, + "Failed to reboot with parameter, retrying without: %m"); + } + } + + if (!(flags & REBOOT_FALLBACK)) + return 0; + + log_full(flags & REBOOT_LOG ? LOG_INFO : LOG_DEBUG, "Rebooting."); + + if (flags & REBOOT_DRY_RUN) + return 0; + + (void) reboot(RB_AUTOBOOT); + + return log_full_errno(flags & REBOOT_LOG ? LOG_ERR : LOG_DEBUG, errno, "Failed to reboot: %m"); +} + +bool shall_restore_state(void) { + static int cached = -1; + bool b = true; /* If nothing specified or the check fails, then defaults to true. */ + int r; + + if (cached >= 0) + return cached; + + r = proc_cmdline_get_bool("systemd.restore_state", PROC_CMDLINE_TRUE_WHEN_MISSING, &b); + if (r < 0) + log_debug_errno(r, "Failed to parse systemd.restore_state= kernel command line option, ignoring: %m"); + + return (cached = b); +} + +static int xen_kexec_loaded(void) { +#if HAVE_XENCTRL + _cleanup_close_ int privcmd_fd = -EBADF, buf_fd = -EBADF; + xen_kexec_status_t *buffer; + size_t size; + int r; + + if (access("/proc/xen", F_OK) < 0) { + if (errno == ENOENT) + return -EOPNOTSUPP; + return log_debug_errno(errno, "Unable to test whether /proc/xen exists: %m"); + } + + size = page_size(); + if (sizeof(xen_kexec_status_t) > size) + return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "page_size is too small for hypercall"); + + privcmd_fd = open("/dev/xen/privcmd", O_RDWR|O_CLOEXEC); + if (privcmd_fd < 0) + return log_debug_errno(errno, "Cannot access /dev/xen/privcmd: %m"); + + buf_fd = open("/dev/xen/hypercall", O_RDWR|O_CLOEXEC); + if (buf_fd < 0) + return log_debug_errno(errno, "Cannot access /dev/xen/hypercall: %m"); + + buffer = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, buf_fd, 0); + if (buffer == MAP_FAILED) + return log_debug_errno(errno, "Cannot allocate buffer for hypercall: %m"); + + *buffer = (xen_kexec_status_t) { + .type = KEXEC_TYPE_DEFAULT, + }; + + privcmd_hypercall_t call = { + .op = __HYPERVISOR_kexec_op, + .arg = { + KEXEC_CMD_kexec_status, + PTR_TO_UINT64(buffer), + }, + }; + + r = RET_NERRNO(ioctl(privcmd_fd, IOCTL_PRIVCMD_HYPERCALL, &call)); + if (r < 0) + log_debug_errno(r, "kexec_status failed: %m"); + + munmap(buffer, size); + + return r; +#else + return -EOPNOTSUPP; +#endif +} + +bool kexec_loaded(void) { + _cleanup_free_ char *s = NULL; + int r; + + r = xen_kexec_loaded(); + if (r >= 0) + return r; + + r = read_one_line_file("/sys/kernel/kexec_loaded", &s); + if (r < 0) { + if (r != -ENOENT) + log_debug_errno(r, "Unable to read /sys/kernel/kexec_loaded, ignoring: %m"); + return false; + } + + return s[0] == '1'; +} |