From: Pavel Machek <pavel@ucw.cz>
software_suspend() can fail for quite a lot of reasons (for example not
enough swapspace). However current interface returned void, so you could
not propagate error back to userland. This fixes it. Plus
__read_suspend_image() is only done during init time, so we might as well
mark it __init.
---
include/linux/suspend.h | 26 +++++++++++++++++++-------
kernel/power/swsusp.c | 35 +++++++++++++++++------------------
kernel/sys.c | 8 +++-----
3 files changed, 39 insertions(+), 30 deletions(-)
diff -puN include/linux/suspend.h~swsusp-software_suspend-retval-fix include/linux/suspend.h
--- 25/include/linux/suspend.h~swsusp-software_suspend-retval-fix 2004-01-20 21:32:38.000000000 -0800
+++ 25-akpm/include/linux/suspend.h 2004-01-20 21:32:38.000000000 -0800
@@ -42,31 +42,43 @@ extern int shrink_mem(void);
/* mm/page_alloc.c */
extern void drain_local_pages(void);
+/* kernel/power/swsusp.c */
+extern int software_suspend(void);
+
extern unsigned int nr_copy_pages __nosavedata;
extern suspend_pagedir_t *pagedir_nosave __nosavedata;
-#endif /* CONFIG_PM */
-
-#ifdef CONFIG_SOFTWARE_SUSPEND
-
-extern unsigned char software_suspend_enabled;
-extern void software_suspend(void);
#else /* CONFIG_SOFTWARE_SUSPEND */
-static inline void software_suspend(void)
+static inline int software_suspend(void)
{
printk("Warning: fake suspend called\n");
+ return -EPERM;
}
+#define software_resume() do { } while(0)
#endif /* CONFIG_SOFTWARE_SUSPEND */
#ifdef CONFIG_PM
extern void refrigerator(unsigned long);
+extern int freeze_processes(void);
+extern void thaw_processes(void);
+
+extern int pm_prepare_console(void);
+extern void pm_restore_console(void);
#else
static inline void refrigerator(unsigned long flag)
{
}
+static inline int freeze_processes(void)
+{
+ return 0;
+}
+static inline void thaw_processes(void)
+{
+
+}
#endif /* CONFIG_PM */
#endif /* _LINUX_SWSUSP_H */
diff -puN kernel/power/swsusp.c~swsusp-software_suspend-retval-fix kernel/power/swsusp.c
--- 25/kernel/power/swsusp.c~swsusp-software_suspend-retval-fix 2004-01-20 21:32:38.000000000 -0800
+++ 25-akpm/kernel/power/swsusp.c 2004-01-20 21:32:38.000000000 -0800
@@ -677,11 +677,22 @@ void do_magic_suspend_2(void)
mark_swapfiles(((swp_entry_t) {0}), MARK_SWAP_RESUME);
}
-static void do_software_suspend(void)
+/*
+ * This is main interface to the outside world. It needs to be
+ * called from process context.
+ */
+int software_suspend(void)
{
+ int res;
+ if (!software_suspend_enabled)
+ return -EAGAIN;
+
+ software_suspend_enabled = 0;
+ might_sleep();
+
if (arch_prepare_suspend()) {
printk("%sArchitecture failed to prepare\n", name_suspend);
- return;
+ return -EPERM;
}
if (pm_prepare_console())
printk( "%sCan't allocate a console... proceeding\n", name_suspend);
@@ -711,24 +722,12 @@ static void do_software_suspend(void)
*/
do_magic(0);
thaw_processes();
- }
+ } else
+ res = -EBUSY;
software_suspend_enabled = 1;
MDELAY(1000);
pm_restore_console();
-}
-
-/*
- * This is main interface to the outside world. It needs to be
- * called from process context.
- */
-void software_suspend(void)
-{
- if(!software_suspend_enabled)
- return;
-
- software_suspend_enabled = 0;
- might_sleep();
- do_software_suspend();
+ return res;
}
/* More restore stuff */
@@ -898,7 +897,7 @@ static int bdev_write_page(struct block_
extern dev_t __init name_to_dev_t(const char *line);
-static int __read_suspend_image(struct block_device *bdev, union diskpage *cur, int noresume)
+static int __init __read_suspend_image(struct block_device *bdev, union diskpage *cur, int noresume)
{
swp_entry_t next;
int i, nr_pgdir_pages;
diff -puN kernel/sys.c~swsusp-software_suspend-retval-fix kernel/sys.c
--- 25/kernel/sys.c~swsusp-software_suspend-retval-fix 2004-01-20 21:32:38.000000000 -0800
+++ 25-akpm/kernel/sys.c 2004-01-20 21:32:38.000000000 -0800
@@ -475,13 +475,11 @@ asmlinkage long sys_reboot(int magic1, i
#ifdef CONFIG_SOFTWARE_SUSPEND
case LINUX_REBOOT_CMD_SW_SUSPEND:
- if (!software_suspend_enabled) {
+ {
+ int ret = software_suspend();
unlock_kernel();
- return -EAGAIN;
+ return ret;
}
- software_suspend();
- do_exit(0);
- break;
#endif
default:
_