[ .. ]Hi!
In priciple it looks okay, but minor details still need to be ironed out.
Cool. THX.
Not so easy. blkdev_put() is done implicitely by open_by_devnum().At one point you did something like
read_data() blk_device_put()
If read_data does blk_device_get(), it should also do the put() itself. Otherwise some caller will forget it.
So if that fails we have to do it by hand (cf. swsusp_check()).
And I'll keep the reference to the block device open to avoid duplicate checking in swsusp_read(). So I'll have to close it there as the block device is local to swsusp.c.
But you are correct in another point, in that there is an error path when prepare_processes fails we have to drop the reference again.
swsusp_check is used by both entry points, and is itself not a init function.--- linux-2.6.10/init/do_mounts.c.orig 2005-01-28 10:25:35.000000000 +0100 +++ linux-2.6.10/init/do_mounts.c 2005-01-28 10:30:43.000000000 +0100 @@ -135,7 +135,7 @@ fail: * is mounted on rootfs /sys. */
-dev_t __init name_to_dev_t(char *name) +dev_t name_to_dev_t(char *name) { char s[32]; char *p;
Why do you need this one? /sys/power/resume accepts numeric values, it should not need to translate...
I simply found it bad style to reference a __init function from there.
And name_to_dev_t is evil in itself. I'd gladly be rid of it if possible.
If /sys is mounted the device lookup will fail. How sane is that?
@@ -144,7 +144,8 @@ dev_t __init name_to_dev_t(char *name)
#ifdef CONFIG_SYSFS int mkdir_err = sys_mkdir("/sys", 0700); - if (sys_mount("sysfs", "/sys", "sysfs", 0, NULL) < 0) + int mount_err = sys_mount("sysfs", "/sys", "sysfs", 0, NULL); + if (mount_err < 0 && mount_err != -EBUSY) goto out; #endif
This is probably not acceptable. Why do you need it? It should be easily doable from initrd.
But yes, it doesn't belong to this patch, so I'll be sending a separate one for it.
[ .. ]
What does freeze_processes() == 1 mean and why is it suddenly ok?
Sorry, leftover. Cleaned up.
+ if (sscanf(buf, "%u:%u", &maj, &min) == 2) { + res = MKDEV(maj,min); + if (maj == MAJOR(res) && min == MINOR(res)) { + swsusp_resume_device = res; + printk("Attempting manual resume\n"); + noresume = 0; + set_current_state(TASK_STOPPED); + software_resume(); + set_current_state(TASK_RUNNING);
Ugh, now that is "interesting" hack. You set yourself as stopped to avoid refrigerator.... Is it really needed?
No, again a leftover.
How about this version? Better?
Cheers,
Hannes -- Subject: activate resume from initramfs From: [EMAIL PROTECTED]
When using a fully modularized kernel it is necessary to activate resume manually as the device node might not be available during kernel init.
This patch implements a new sysfs attribute '/sys/power/resume' which allows for manual activation of software resume. When read from it prints the configured resume device in 'major:minor' format. When written to it expects a device in 'major:minor' format. This device is then checked for a suspended image and resume is started if a valid image is found. The original functionality is left in place.
It should only be used from initramfs; other usage will most likely not work.
Signed-off-by: Hannes Reinecke <[EMAIL PROTECTED]>
--- linux-2.6.10/init/do_mounts.c.orig 2005-01-31 13:54:17.000000000 +0100
+++ linux-2.6.10/init/do_mounts.c 2005-01-31 14:46:08.000000000 +0100
@@ -53,7 +53,7 @@ static int __init readwrite(char *str)
__setup("ro", readonly);
__setup("rw", readwrite);-static dev_t __init try_name(char *name, int part)
+static dev_t try_name(char *name, int part)
{
char path[64];
char buf[32];
@@ -135,7 +135,7 @@ fail:
* is mounted on rootfs /sys.
*/-dev_t __init name_to_dev_t(char *name)
+dev_t name_to_dev_t(char *name)
{
char s[32];
char *p;
--- linux-2.6.10/kernel/power/disk.c.orig 2005-01-31 13:54:17.000000000 +0100
+++ linux-2.6.10/kernel/power/disk.c 2005-01-31 14:55:14.000000000 +0100
@@ -9,6 +9,8 @@
*
*/
+#define DEBUG + #include <linux/suspend.h> #include <linux/syscalls.h> #include <linux/reboot.h> @@ -25,13 +27,16 @@ extern struct pm_ops * pm_ops;
extern int swsusp_suspend(void); extern int swsusp_write(void); +extern int swsusp_check(void); extern int swsusp_read(void); +extern void swsusp_close(void); extern int swsusp_resume(void); extern int swsusp_free(void);
static int noresume = 0; char resume_file[256] = CONFIG_PM_STD_PARTITION; +dev_t swsusp_resume_device;
/** * power_down - Shut machine down for hibernate. @@ -121,45 +126,54 @@ static void finish(void) }
-static int prepare(void) +static int prepare_processes(void) { int error;
pm_prepare_console();
sys_sync();
+
if (freeze_processes()) {
error = -EBUSY;
- goto Thaw;
+ return error;
} if (pm_disk_mode == PM_DISK_PLATFORM) {
if (pm_ops && pm_ops->prepare) {
if ((error = pm_ops->prepare(PM_SUSPEND_DISK)))
- goto Thaw;
+ return error;
}
} /* Free memory before shutting down devices. */
free_some_memory();+ return 0;
+}
+
+static void unprepare_processes(void)
+{
+ enable_nonboot_cpus();
+ thaw_processes();
+ pm_restore_console();
+}
+
+static int prepare_devices(void)
+{
+ int error;
+
disable_nonboot_cpus();
if ((error = device_suspend(PMSG_FREEZE))) {
printk("Some devices failed to suspend\n");
- goto Finish;
+ platform_finish();
+ enable_nonboot_cpus();
+ return error;
}return 0; - Finish: - platform_finish(); - Thaw: - enable_nonboot_cpus(); - thaw_processes(); - pm_restore_console(); - return error; }
-
/**
* pm_suspend_disk - The granpappy of power management.
*
@@ -173,8 +187,15 @@ int pm_suspend_disk(void)
{
int error;- if ((error = prepare()))
+ error = prepare_processes();
+ if (!error) {
+ error = prepare_devices();
+ }
+
+ if (error) {
+ unprepare_processes();
return error;
+ } pr_debug("PM: Attempting to suspend to disk.\n");
if (pm_disk_mode == PM_DISK_FIRMWARE)
@@ -223,14 +244,26 @@ static int software_resume(void)
return 0;
}+ pr_debug("PM: Checking swsusp image.\n");
+
+ if ((error = swsusp_check()))
+ goto Done;
+
+ pr_debug("PM: Preparing processes for restore.\n");
+
+ if ((error = prepare_processes())) {
+ swsusp_close();
+ goto Cleanup;
+ }
+
pr_debug("PM: Reading swsusp image.\n");if ((error = swsusp_read())) - goto Done; + goto Cleanup;
- pr_debug("PM: Preparing system for restore.\n");
+ pr_debug("PM: Preparing devices for restore.\n");- if ((error = prepare()))
+ if ((error = prepare_devices()))
goto Free; barrier();
@@ -242,6 +275,8 @@ static int software_resume(void)
finish();
Free:
swsusp_free();
+ Cleanup:
+ unprepare_processes();
Done:
pr_debug("PM: Resume from disk failed.\n");
return 0;
@@ -329,8 +364,41 @@ static ssize_t disk_store(struct subsystpower_attr(disk);
+static ssize_t resume_show(struct subsystem * subsys, char *buf)
+{
+ return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
+ MINOR(swsusp_resume_device));
+}
+
+static ssize_t resume_store(struct subsystem * subsys, const char * buf, size_t n)
+{
+ int len;
+ char *p;
+ unsigned int maj, min;
+ int error = -EINVAL;
+ dev_t res;
+
+ p = memchr(buf, '\n', n);
+ len = p ? p - buf : n;
+
+ if (sscanf(buf, "%u:%u", &maj, &min) == 2) {
+ res = MKDEV(maj,min);
+ if (maj == MAJOR(res) && min == MINOR(res)) {
+ swsusp_resume_device = res;
+ printk("Attempting manual resume\n");
+ noresume = 0;
+ software_resume();
+ }
+ }
+
+ return error >= 0 ? n : error;
+}
+
+power_attr(resume);
+
static struct attribute * g[] = {
&disk_attr.attr,
+ &resume_attr.attr,
NULL,
};
--- linux-2.6.10/kernel/power/swsusp.c.orig 2005-01-31 13:54:17.000000000 +0100
+++ linux-2.6.10/kernel/power/swsusp.c 2005-01-31 14:53:36.000000000 +0100
@@ -36,6 +36,8 @@
* For TODOs,FIXMEs also look in Documentation/power/swsusp.txt
*/
+#define DEBUG + #include <linux/module.h> #include <linux/mm.h> #include <linux/suspend.h> @@ -80,7 +82,7 @@ static int pagedir_order_check; static int nr_copy_pages_check;
extern char resume_file[]; -static dev_t resume_device; + /* Local variables that should not be affected by save */ unsigned int nr_copy_pages __nosavedata = 0;
@@ -170,7 +172,7 @@ static int is_resume_device(const struct
struct inode *inode = file->f_dentry->d_inode;return S_ISBLK(inode->i_mode) && - resume_device == MKDEV(imajor(inode), iminor(inode)); + swsusp_resume_device == MKDEV(imajor(inode), iminor(inode)); }
static int swsusp_swap_check(void) /* This is called before saving image */
@@ -898,7 +900,7 @@ int swsusp_resume(void)
/*
* Returns true if given address/order collides with any orig_address
*/
-static int __init does_collide_order(unsigned long addr, int order)
+static int does_collide_order(unsigned long addr, int order)
{
int i;
@@ -912,7 +914,7 @@ static int __init does_collide_order(uns
* We check here that pagedir & pages it points to won't collide with pages
* where we're going to restore from the loaded pages later
*/
-static int __init check_pagedir(void)
+static int check_pagedir(void)
{
int i;
@@ -930,7 +932,7 @@ static int __init check_pagedir(void)
return 0;
}-static int __init swsusp_pagedir_relocate(void)
+static int swsusp_pagedir_relocate(void)
{
/*
* We have to avoid recursion (not to overflow kernel stack),
@@ -1075,7 +1077,7 @@ static int bio_write_page(pgoff_t page_o
* I really don't think that it's foolproof but more than nothing..
*/-static const char * __init sanity_check(void)
+static const char * sanity_check(void)
{
dump_info();
if(swsusp_info.version_code != LINUX_VERSION_CODE)
@@ -1096,7 +1098,7 @@ static const char * __init sanity_check(
}
-static int __init check_header(void) +static int check_header(void) { const char * reason = NULL; int error; @@ -1114,7 +1116,7 @@ static int __init check_header(void) return error; }
-static int __init check_sig(void)
+static int check_sig(void)
{
int error;@@ -1144,7 +1146,7 @@ static int __init check_sig(void) * already did that. */
-static int __init data_read(void)
+static int data_read(void)
{
struct pbe * p;
int error;
@@ -1169,9 +1171,9 @@ static int __init data_read(void)}
-extern dev_t __init name_to_dev_t(const char *line); +extern dev_t name_to_dev_t(const char *line);
-static int __init read_pagedir(void)
+static int read_pagedir(void)
{
unsigned long addr;
int i, n = swsusp_info.pagedir_pages;
@@ -1196,7 +1198,7 @@ static int __init read_pagedir(void)
return error;
}-static int __init read_suspend_image(void)
+static int check_suspend_image(void)
{
int error = 0;@@ -1204,6 +1206,13 @@ static int __init read_suspend_image(voi
return error;
if ((error = check_header()))
return error;
+ return error;
+}
+
+static int read_suspend_image(void)
+{
+ int error = 0;
+
if ((error = read_pagedir()))
return error;
if ((error = data_read()))
@@ -1212,30 +1221,74 @@ static int __init read_suspend_image(voi
}/** - * swsusp_read - Read saved image from swap. + * swsusp_check - Check for saved image in swap */
-int __init swsusp_read(void)
+int swsusp_check(void)
{
int error;- if (!strlen(resume_file))
- return -ENOENT;
-
- resume_device = name_to_dev_t(resume_file);
- pr_debug("swsusp: Resume From Partition: %s\n", resume_file);
+ if (!swsusp_resume_device) {
+ if (!strlen(resume_file))
+ return -ENOENT;
+ swsusp_resume_device = name_to_dev_t(resume_file);
+ pr_debug("swsusp: Resume From Partition %s\n", resume_file);
+ } else {
+ pr_debug("swsusp: Resume From Partition %d:%d\n",
+ MAJOR(swsusp_resume_device),
MINOR(swsusp_resume_device));
+ }- resume_bdev = open_by_devnum(resume_device, FMODE_READ);
+ resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
if (!IS_ERR(resume_bdev)) {
set_blocksize(resume_bdev, PAGE_SIZE);
- error = read_suspend_image();
- blkdev_put(resume_bdev);
+ error = check_suspend_image();
+ if (error)
+ blkdev_put(resume_bdev);
} else
error = PTR_ERR(resume_bdev);if (!error)
- pr_debug("Reading resume file was successful\n");
+ pr_debug("swsusp: resume file found\n");
+ else
+ pr_debug("swsusp: Error %d check for resume file\n", error);
+ return error;
+}
+
+/**
+ * swsusp_read - Read saved image from swap.
+ */
+
+int swsusp_read(void)
+{
+ int error;
+
+ if (IS_ERR(resume_bdev)) {
+ pr_debug("swsusp: block device not initialised\n");
+ return PTR_ERR(resume_bdev);
+ }
+
+ error = read_suspend_image();
+ blkdev_put(resume_bdev);
+
+ if (!error)
+ pr_debug("swsusp: Reading resume file was successful\n");
else
pr_debug("swsusp: Error %d resuming\n", error);
return error;
}
+
+/**
+ * swsusp_close - close swap device.
+ */
+
+int swsusp_close(void)
+{
+ int error;
+
+ if (IS_ERR(resume_bdev)) {
+ pr_debug("swsusp: block device not initialised\n");
+ return;
+ }
+
+ blkdev_put(resume_bdev);
+}
--- linux-2.6.10/include/linux/suspend.h.orig 2005-01-31 13:54:17.000000000 +0100
+++ linux-2.6.10/include/linux/suspend.h 2005-01-31 13:54:33.000000000 +0100
@@ -25,6 +25,8 @@ typedef struct pbe {
#define SUSPEND_PD_PAGES(x) (((x)*sizeof(struct pbe))/PAGE_SIZE+1) + +extern dev_t swsusp_resume_device;
/* mm/vmscan.c */ extern int shrink_mem(void); -- Dr. Hannes Reinecke [EMAIL PROTECTED] SuSE Linux AG S390 & zSeries Maxfeldstra�e 5 +49 911 74053 688 90409 N�rnberg http://www.suse.de - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
