discover: Allow an in-progress boot to be cancelled

Currently, once the boot() function is called, the boot process will
ignore any cancellations.

This change allows boot() to be cancelled, via boot_cancel().

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

diff --git a/discover/boot.c b/discover/boot.c
index ec6f6e579eb6cb31f8929c1ab140accc9be99b35..0237b0c962209fe65aa8b2f394946adbc24d656f 100644 (file)
--- a/discover/boot.c
+++ b/discover/boot.c
@@ -9,6 +9,7 @@
 #include <fcntl.h>
 #include <sys/types.h>
 
 #include <fcntl.h>
 #include <sys/types.h>
 

+#include <array-size/array-size.h>

 #include <log/log.h>
 #include <pb-protocol/pb-protocol.h>
 #include <process/process.h>
 #include <log/log.h>
 #include <pb-protocol/pb-protocol.h>
 #include <process/process.h>


@@ -35,6 +36,7 @@ struct boot_task {
        boot_status_fn status_fn;
        void *status_arg;
        bool dry_run;
        boot_status_fn status_fn;
        void *status_arg;
        bool dry_run;

+       bool cancelled;

 };
 
 /**
 };
 
 /**


@@ -308,12 +310,50 @@ static void cleanup_load(struct load_url_result *result)
        unlink(result->local);
 }
 
        unlink(result->local);
 }
 

-static void boot_process(struct load_url_result *result __attribute__((unused)),
-               void *data)
+static void cleanup_cancellations(struct boot_task *task,
+               struct load_url_result *cur_result)
+{
+       struct load_url_result *result, **results[] = {
+               &task->image, &task->initrd, &task->dtb,
+       };
+       bool pending = false;
+       unsigned int i;
+
+       for (i = 0; i < ARRAY_SIZE(results); i++) {
+               result = *results[i];
+
+               if (!result)
+                       continue;
+
+               /* We need to cleanup and free any completed loads */
+               if (result == cur_result || result->status == LOAD_OK
+                               || result->status == LOAD_ERROR) {
+                       cleanup_load(result);
+                       talloc_free(result);
+                       *results[i] = NULL;
+
+               /* ... and cancel any pending loads, which we'll free in
+                * the completion callback */
+               } else if (result->status == LOAD_ASYNC) {
+                       load_url_async_cancel(result);
+                       pending = true;
+               }
+       }
+
+       if (!pending)
+               talloc_free(task);
+}
+
+static void boot_process(struct load_url_result *result, void *data)

 {
        struct boot_task *task = data;
        int rc = -1;
 
 {
        struct boot_task *task = data;
        int rc = -1;
 

+       if (task->cancelled) {
+               cleanup_cancellations(task, result);
+               return;
+       }
+

        if (load_pending(task->image) ||
                        load_pending(task->initrd) ||
                        load_pending(task->dtb))
        if (load_pending(task->image) ||
                        load_pending(task->initrd) ||
                        load_pending(task->dtb))


@@ -352,8 +392,6 @@ no_load:
                                        "kexec reboot failed");
                }
        }
                                        "kexec reboot failed");
                }
        }

-
-       talloc_free(task);

 }
 
 static int start_url_load(struct boot_task *task, const char *name,
 }
 
 static int start_url_load(struct boot_task *task, const char *name,


@@ -372,8 +410,9 @@ static int start_url_load(struct boot_task *task, const char *name,
        return 0;
 }
 
        return 0;
 }
 

-int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
-               int dry_run, boot_status_fn status_fn, void *status_arg)
+struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
+               struct boot_command *cmd, int dry_run,
+               boot_status_fn status_fn, void *status_arg)

 {
        struct pb_url *image = NULL, *initrd = NULL, *dtb = NULL;
        struct boot_task *boot_task;
 {
        struct pb_url *image = NULL, *initrd = NULL, *dtb = NULL;
        struct boot_task *boot_task;


@@ -398,7 +437,7 @@ int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
                pb_log("%s: no image specified\n", __func__);
                update_status(status_fn, status_arg, BOOT_STATUS_INFO,
                                "Boot failed: no image specified");
                pb_log("%s: no image specified\n", __func__);
                update_status(status_fn, status_arg, BOOT_STATUS_INFO,
                                "Boot failed: no image specified");

-               return -1;
+               return NULL;

        }
 
        if (cmd && cmd->initrd_file) {
        }
 
        if (cmd && cmd->initrd_file) {


@@ -433,8 +472,22 @@ int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
          || start_url_load(boot_task, "dtb", dtb, &boot_task->dtb);
 
        /* If all URLs are local, we may be done. */
          || start_url_load(boot_task, "dtb", dtb, &boot_task->dtb);
 
        /* If all URLs are local, we may be done. */

-       if (!rc)
-               boot_process(NULL, boot_task);
+       if (rc) {
+               talloc_free(boot_task);
+               return NULL;
+       }
+
+       boot_process(NULL, boot_task);
+
+       return boot_task;
+}
+
+void boot_cancel(struct boot_task *task)
+{
+       task->cancelled = true;
+
+       update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
+                       "Boot cancelled");

 
 

-       return rc;
+       cleanup_cancellations(task, NULL);

 }
 }

diff --git a/discover/boot.h b/discover/boot.h
index bbb02cf7858e39e0f077fc42e56538c2b9a1f65b..ec61703144c5409aa77b71de2ce54d254839de0e 100644 (file)
--- a/discover/boot.h
+++ b/discover/boot.h
@@ -6,7 +6,9 @@ struct boot_command;
 
 typedef void (*boot_status_fn)(void *arg, struct boot_status *);
 
 
 typedef void (*boot_status_fn)(void *arg, struct boot_status *);
 

-int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
-               int dry_run, boot_status_fn status_fn, void *status_arg);
+struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
+               struct boot_command *cmd, int dry_run,
+               boot_status_fn status_fn, void *status_arg);

 
 

+void boot_cancel(struct boot_task *task);

 #endif /* _BOOT_H */
 #endif /* _BOOT_H */

diff --git a/discover/device-handler.c b/discover/device-handler.c
index 142f6a490028508056415ab99e78f020f035b309..af9fbba3e0dfbd3803772659c1adca6e377375d3 100644 (file)
--- a/discover/device-handler.c
+++ b/discover/device-handler.c
@@ -40,6 +40,9 @@ struct device_handler {
 
        struct discover_boot_option *default_boot_option;
        struct list             unresolved_boot_options;
 
        struct discover_boot_option *default_boot_option;
        struct list             unresolved_boot_options;

+
+       struct boot_task        *pending_boot;
+       bool                    pending_boot_is_default;

 };
 
 static int mount_device(struct discover_device *dev);
 };
 
 static int mount_device(struct discover_device *dev);


@@ -331,6 +334,9 @@ static int default_timeout(void *arg)
        if (!handler->default_boot_option)
                return 0;
 
        if (!handler->default_boot_option)
                return 0;
 

+       if (handler->pending_boot)
+               return 0;
+

        opt = handler->default_boot_option;
 
        if (handler->sec_to_boot) {
        opt = handler->default_boot_option;
 
        if (handler->sec_to_boot) {


@@ -346,8 +352,9 @@ static int default_timeout(void *arg)
 
        pb_log("Timeout expired, booting default option %s\n", opt->option->id);
 
 
        pb_log("Timeout expired, booting default option %s\n", opt->option->id);
 

-       boot(handler, handler->default_boot_option, NULL,
-                       handler->dry_run, boot_status, handler);
+       handler->pending_boot = boot(handler, handler->default_boot_option,
+                       NULL, handler->dry_run, boot_status, handler);
+       handler->pending_boot_is_default = true;

        return 0;
 }
 
        return 0;
 }
 


@@ -655,7 +662,11 @@ void device_handler_boot(struct device_handler *handler,
        if (cmd->option_id && strlen(cmd->option_id))
                opt = find_boot_option_by_id(handler, cmd->option_id);
 
        if (cmd->option_id && strlen(cmd->option_id))
                opt = find_boot_option_by_id(handler, cmd->option_id);
 

-       boot(handler, opt, cmd, handler->dry_run, boot_status, handler);
+       if (handler->pending_boot)
+               boot_cancel(handler->pending_boot);
+       handler->pending_boot = boot(handler, opt, cmd, handler->dry_run,
+                       boot_status, handler);
+       handler->pending_boot_is_default = false;

 }
 
 void device_handler_cancel_default(struct device_handler *handler)
 }
 
 void device_handler_cancel_default(struct device_handler *handler)


@@ -674,6 +685,12 @@ void device_handler_cancel_default(struct device_handler *handler)
 
        pb_log("Cancelling default boot option\n");
 
 
        pb_log("Cancelling default boot option\n");
 

+       if (handler->pending_boot && handler->pending_boot_is_default) {
+               boot_cancel(handler->pending_boot);
+               handler->pending_boot = NULL;
+               handler->pending_boot_is_default = false;
+       }
+

        handler->default_boot_option = NULL;
 
        status.type = BOOT_STATUS_INFO;
        handler->default_boot_option = NULL;
 
        status.type = BOOT_STATUS_INFO;

diff --git a/test/parser/handler.c b/test/parser/handler.c
index 437f76591b9b65b37e629b0775ce2df4a29f249c..64978da92f745988fdfc871718981105d51b9e5a 100644 (file)
--- a/test/parser/handler.c
+++ b/test/parser/handler.c
@@ -47,8 +47,9 @@ void iterate_parsers(struct discover_context *ctx, enum conf_method method)
        assert(false);
 }
 
        assert(false);
 }
 

-int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
-               int dry_run, boot_status_fn status_fn, void *status_arg)
+struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
+               struct boot_command *cmd, int dry_run,
+               boot_status_fn status_fn, void *status_arg)

 {
        (void)ctx;
        (void)opt;
 {
        (void)ctx;
        (void)opt;


@@ -58,3 +59,8 @@ int boot(void *ctx, struct discover_boot_option *opt, struct boot_command *cmd,
        (void)status_arg;
        assert(false);
 }
        (void)status_arg;
        assert(false);
 }

+
+void boot_cancel(struct boot_task *task)
+{
+       (void)task;
+}