Instead of the scripts having to poke at various fields we can provide that functionality via the -S parameter.
kexec_loaded/kexec_crash_loaded exposes Linux kernel kexec/crash state. It does not say anything about Xen kexec/crash state. So, we need a special approach to get the latter. Though for compatibility we provide similar functionality in kexec-tools for the former. This change enables the --status or -S option to work either with or without Xen. Returns 0 if the payload is loaded. Can be used in combination with -l or -p to get the state of the proper kexec image. Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> Signed-off-by: Eric DeVolder <eric.devol...@oracle.com> --- CC: kexec@lists.infradead.org CC: xen-de...@lists.xenproject.org CC: Daniel Kiper <daniel.ki...@oracle.com> v0: First version (internal product). v1: Posted on kexec mailing list. Changed -s to -S v2: Incorporated feedback from kexec mailing list, posted on kexec mailing list v3: Incorporated feedback from kexec mailing list, posted on kexec mailing list v4: Incorporated feedback from kexec mailing list --- configure.ac | 8 +++- kexec/kexec-xen.c | 26 +++++++++++++ kexec/kexec.8 | 6 +++ kexec/kexec.c | 114 ++++++++++++++++++++++++++++++++++++++---------------- kexec/kexec.h | 5 ++- 5 files changed, 123 insertions(+), 36 deletions(-) diff --git a/configure.ac b/configure.ac index 3044185..53fffc3 100644 --- a/configure.ac +++ b/configure.ac @@ -165,8 +165,14 @@ fi dnl find Xen control stack libraries if test "$with_xen" = yes ; then AC_CHECK_HEADER(xenctrl.h, - [AC_CHECK_LIB(xenctrl, xc_kexec_load, , + [AC_CHECK_LIB(xenctrl, xc_kexec_load, [ have_xenctrl_h=yes ], AC_MSG_NOTICE([Xen support disabled]))]) + if test "$have_xenctrl_h" = yes ; then + AC_CHECK_LIB(xenctrl, xc_kexec_status, + AC_DEFINE(HAVE_KEXEC_CMD_STATUS, 1, + [The kexec_status call is available]), + AC_MSG_NOTICE([The kexec_status call is not available])) + fi fi dnl ---Sanity checks diff --git a/kexec/kexec-xen.c b/kexec/kexec-xen.c index 24a4191..2b448d3 100644 --- a/kexec/kexec-xen.c +++ b/kexec/kexec-xen.c @@ -105,6 +105,27 @@ int xen_kexec_unload(uint64_t kexec_flags) return ret; } +int xen_kexec_status(uint64_t kexec_flags) +{ + xc_interface *xch; + uint8_t type; + int ret = -1; + +#ifdef HAVE_KEXEC_CMD_STATUS + xch = xc_interface_open(NULL, NULL, 0); + if (!xch) + return -1; + + type = (kexec_flags & KEXEC_ON_CRASH) ? KEXEC_TYPE_CRASH : KEXEC_TYPE_DEFAULT; + + ret = xc_kexec_status(xch, type); + + xc_interface_close(xch); +#endif + + return ret; +} + void xen_kexec_exec(void) { xc_interface *xch; @@ -130,6 +151,11 @@ int xen_kexec_unload(uint64_t kexec_flags) return -1; } +int xen_kexec_status(uint64_t kexec_flags) +{ + return -1; +} + void xen_kexec_exec(void) { } diff --git a/kexec/kexec.8 b/kexec/kexec.8 index 4d0c1d1..f4b39a6 100644 --- a/kexec/kexec.8 +++ b/kexec/kexec.8 @@ -107,6 +107,12 @@ command: .B \-d\ (\-\-debug) Enable debugging messages. .TP +.B \-S\ (\-\-status) +Return 0 if the type (by default crash) is loaded. Can be used in conjuction +with -l or -p to toggle the type. Note this option supersedes other options +and it will +.BR not\ load\ or\ unload\ the\ kernel. +.TP .B \-e\ (\-\-exec) Run the currently loaded kernel. Note that it will reboot into the loaded kernel without calling shutdown(8). .TP diff --git a/kexec/kexec.c b/kexec/kexec.c index 500e5a9..ec16247 100644 --- a/kexec/kexec.c +++ b/kexec/kexec.c @@ -51,6 +51,9 @@ #include "kexec-lzma.h" #include <arch/options.h> +#define KEXEC_LOADED_PATH "/sys/kernel/kexec_loaded" +#define KEXEC_CRASH_LOADED_PATH "/sys/kernel/kexec_crash_loaded" + unsigned long long mem_min = 0; unsigned long long mem_max = ULONG_MAX; static unsigned long kexec_flags = 0; @@ -890,8 +893,6 @@ static int my_exec(void) return -1; } -static int kexec_loaded(void); - static int load_jump_back_helper_image(unsigned long kexec_flags, void *entry) { int result; @@ -902,6 +903,40 @@ static int load_jump_back_helper_image(unsigned long kexec_flags, void *entry) return result; } +static int kexec_loaded(const char *file) +{ + long ret = -1; + FILE *fp; + char *p; + char line[3]; + + /* No way to tell if an image is loaded under Xen, assume it is. */ + if (xen_present()) + return 1; + + fp = fopen(file, "r"); + if (fp == NULL) + return -1; + + p = fgets(line, sizeof(line), fp); + fclose(fp); + + if (p == NULL) + return -1; + + ret = strtol(line, &p, 10); + + /* Too long */ + if (ret > INT_MAX) + return -1; + + /* No digits were found */ + if (p == line) + return -1; + + return (int)ret; +} + /* * Jump back to the original kernel */ @@ -909,7 +944,7 @@ static int my_load_jump_back_helper(unsigned long kexec_flags, void *entry) { int result; - if (kexec_loaded()) { + if (kexec_loaded(KEXEC_LOADED_PATH)) { fprintf(stderr, "There is kexec kernel loaded, make sure " "you are in kexeced kernel.\n"); return -1; @@ -970,6 +1005,7 @@ void usage(void) " to original kernel.\n" " -s, --kexec-file-syscall Use file based syscall for kexec operation\n" " -d, --debug Enable debugging to help spot a failure.\n" + " -S, --status Return 0 if the type (by default crash) is loaded.\n" "\n" "Supported kernel file types and options: \n"); for (i = 0; i < file_types; i++) { @@ -981,40 +1017,30 @@ void usage(void) printf("\n"); } -static int kexec_loaded(void) +static int k_status(unsigned long kexec_flags) { - long ret = -1; - FILE *fp; - char *p; - char line[3]; + int result; + long native_arch; + + /* set the arch */ + native_arch = physical_arch(); + if (native_arch < 0) { + return -1; + } + kexec_flags |= native_arch; - /* No way to tell if an image is loaded under Xen, assume it is. */ if (xen_present()) - return 1; - - fp = fopen("/sys/kernel/kexec_loaded", "r"); - if (fp == NULL) - return -1; - - p = fgets(line, sizeof(line), fp); - fclose(fp); - - if (p == NULL) - return -1; - - ret = strtol(line, &p, 10); - - /* Too long */ - if (ret > INT_MAX) - return -1; - - /* No digits were found */ - if (p == line) - return -1; - - return (int)ret; + result = xen_kexec_status(kexec_flags); + else { + if (kexec_flags & KEXEC_ON_CRASH) + result = kexec_loaded(KEXEC_CRASH_LOADED_PATH); + else + result = kexec_loaded(KEXEC_LOADED_PATH); + } + return result; } + /* * Remove parameter from a kernel command line. Helper function by get_command_line(). */ @@ -1204,6 +1230,7 @@ int main(int argc, char *argv[]) int do_unload = 0; int do_reuse_initrd = 0; int do_kexec_file_syscall = 0; + int do_status = 0; void *entry = 0; char *type = 0; char *endptr; @@ -1345,6 +1372,9 @@ int main(int argc, char *argv[]) case OPT_KEXEC_FILE_SYSCALL: /* We already parsed it. Nothing to do. */ break; + case OPT_STATUS: + do_status = 1; + break; default: break; } @@ -1355,6 +1385,20 @@ int main(int argc, char *argv[]) if (skip_sync) do_sync = 0; + if (do_status) { + if (kexec_flags == 0) + kexec_flags = KEXEC_ON_CRASH; + do_load = 0; + do_reuse_initrd = 0; + do_unload = 0; + do_load = 0; + do_shutdown = 0; + do_sync = 0; + do_ifdown = 0; + do_exec = 0; + do_load_jump_back_helper = 0; + } + if (do_load && (kexec_flags & KEXEC_ON_CRASH) && !is_crashkernel_mem_reserved()) { die("Memory for crashkernel is not reserved\n" @@ -1392,7 +1436,9 @@ int main(int argc, char *argv[]) check_reuse_initrd(); arch_reuse_initrd(); } - + if (do_status) { + result = k_status(kexec_flags); + } if (do_unload) { if (do_kexec_file_syscall) result = kexec_file_unload(kexec_file_flags); @@ -1408,7 +1454,7 @@ int main(int argc, char *argv[]) kexec_flags, entry); } /* Don't shutdown unless there is something to reboot to! */ - if ((result == 0) && (do_shutdown || do_exec) && !kexec_loaded()) { + if ((result == 0) && (do_shutdown || do_exec) && !kexec_loaded(KEXEC_LOADED_PATH)) { die("Nothing has been loaded!\n"); } if ((result == 0) && do_shutdown) { diff --git a/kexec/kexec.h b/kexec/kexec.h index 9194f1c..2b06f59 100644 --- a/kexec/kexec.h +++ b/kexec/kexec.h @@ -219,6 +219,7 @@ extern int file_types; #define OPT_TYPE 't' #define OPT_PANIC 'p' #define OPT_KEXEC_FILE_SYSCALL 's' +#define OPT_STATUS 'S' #define OPT_MEM_MIN 256 #define OPT_MEM_MAX 257 #define OPT_REUSE_INITRD 258 @@ -245,8 +246,9 @@ extern int file_types; { "reuseinitrd", 0, 0, OPT_REUSE_INITRD }, \ { "kexec-file-syscall", 0, 0, OPT_KEXEC_FILE_SYSCALL }, \ { "debug", 0, 0, OPT_DEBUG }, \ + { "status", 0, 0, OPT_STATUS }, \ -#define KEXEC_OPT_STR "h?vdfxyluet:ps" +#define KEXEC_OPT_STR "h?vdfxyluet:psS" extern void dbgprint_mem_range(const char *prefix, struct memory_range *mr, int nr_mr); extern void die(const char *fmt, ...) @@ -311,5 +313,6 @@ int xen_present(void); int xen_kexec_load(struct kexec_info *info); int xen_kexec_unload(uint64_t kexec_flags); void xen_kexec_exec(void); +int xen_kexec_status(uint64_t kexec_flags); #endif /* KEXEC_H */ -- 2.7.4 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec