| Message ID | 1520333620-22342-1-git-send-email-mario.limonciello@dell.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
On Tuesday, March 6, 2018 11:53:40 AM CET Mario Limonciello wrote: > Currently the only way to specify a hibernate offset for a > swap file is on the kernel command line. > > Add a new /sys/power/disk_offset that lets userspace > specify the offset and disk to use when initiating a hibernate > cycle. > > Also split up the parsing routine to re-use the same code > for the /sys/power/resume and /sys/power/disk_offset parsing. > > Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> Well, IMO /sys/power/resume and /sys/power/disk_offset would be confusingly similar after this patch. I wonder if adding a resume_offset sysfs attr to simply allow the value of resume offset alone to be passed to the kernel at run time (in addition to the command line) would work? Thanks! -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> -----Original Message----- > From: Rafael J. Wysocki [mailto:rjw@rjwysocki.net] > Sent: Monday, March 19, 2018 5:11 AM > To: Limonciello, Mario <Mario_Limonciello@Dell.com> > Cc: linux-acpi@vger.kernel.org; LKML <linux-kernel@vger.kernel.org> > Subject: Re: [PATCH] power/hibernate: Make passing hibernate offsets more friendly > > On Tuesday, March 6, 2018 11:53:40 AM CET Mario Limonciello wrote: > > Currently the only way to specify a hibernate offset for a > > swap file is on the kernel command line. > > > > Add a new /sys/power/disk_offset that lets userspace > > specify the offset and disk to use when initiating a hibernate > > cycle. > > > > Also split up the parsing routine to re-use the same code > > for the /sys/power/resume and /sys/power/disk_offset parsing. > > > > Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> > > Well, IMO /sys/power/resume and /sys/power/disk_offset would be confusingly > similar after this patch. Yeah they do function pretty similarly. > > I wonder if adding a resume_offset sysfs attr to simply allow the value of > resume offset alone to be passed to the kernel at run time (in addition to > the command line) would work? > > Thanks! I guess what's your expected flow for how the disk gets selected though? Should the kernel be "guessing" which disk to use? Or should userspace be setting offset via /sys/power/resume_offset followed by disk in /sys/power/resume (which will show an error in syslog about no partition found) If the latter, then I'd like to also modify the behavior to downgrade that missing hibernate partition to debug instead too. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Mar 26, 2018 at 9:17 AM, <Mario.Limonciello@dell.com> wrote: >> -----Original Message----- >> From: Rafael J. Wysocki [mailto:rjw@rjwysocki.net] >> Sent: Monday, March 19, 2018 5:11 AM >> To: Limonciello, Mario <Mario_Limonciello@Dell.com> >> Cc: linux-acpi@vger.kernel.org; LKML <linux-kernel@vger.kernel.org> >> Subject: Re: [PATCH] power/hibernate: Make passing hibernate offsets more friendly >> >> On Tuesday, March 6, 2018 11:53:40 AM CET Mario Limonciello wrote: >> > Currently the only way to specify a hibernate offset for a >> > swap file is on the kernel command line. >> > >> > Add a new /sys/power/disk_offset that lets userspace >> > specify the offset and disk to use when initiating a hibernate >> > cycle. >> > >> > Also split up the parsing routine to re-use the same code >> > for the /sys/power/resume and /sys/power/disk_offset parsing. >> > >> > Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> >> >> Well, IMO /sys/power/resume and /sys/power/disk_offset would be confusingly >> similar after this patch. > > Yeah they do function pretty similarly. > >> >> I wonder if adding a resume_offset sysfs attr to simply allow the value of >> resume offset alone to be passed to the kernel at run time (in addition to >> the command line) would work? >> >> Thanks! > > I guess what's your expected flow for how the disk gets selected though? Should > the kernel be "guessing" which disk to use? > > Or should userspace be setting offset via /sys/power/resume_offset followed by > disk in /sys/power/resume (which will show an error in syslog about no partition > found) > > If the latter, Yes, the latter. > then I'd like to also modify the behavior to downgrade that missing > hibernate partition to debug instead too. That's OK. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> -----Original Message----- > From: rjwysocki@gmail.com [mailto:rjwysocki@gmail.com] On Behalf Of Rafael J. > Wysocki > Sent: Monday, March 26, 2018 4:38 AM > To: Limonciello, Mario <Mario_Limonciello@Dell.com> > Cc: Rafael J. Wysocki <rjw@rjwysocki.net>; ACPI Devel Maling List <linux- > acpi@vger.kernel.org>; Linux Kernel Mailing List <linux-kernel@vger.kernel.org> > Subject: Re: [PATCH] power/hibernate: Make passing hibernate offsets more friendly > > On Mon, Mar 26, 2018 at 9:17 AM, <Mario.Limonciello@dell.com> wrote: > >> -----Original Message----- > >> From: Rafael J. Wysocki [mailto:rjw@rjwysocki.net] > >> Sent: Monday, March 19, 2018 5:11 AM > >> To: Limonciello, Mario <Mario_Limonciello@Dell.com> > >> Cc: linux-acpi@vger.kernel.org; LKML <linux-kernel@vger.kernel.org> > >> Subject: Re: [PATCH] power/hibernate: Make passing hibernate offsets more > friendly > >> > >> On Tuesday, March 6, 2018 11:53:40 AM CET Mario Limonciello wrote: > >> > Currently the only way to specify a hibernate offset for a > >> > swap file is on the kernel command line. > >> > > >> > Add a new /sys/power/disk_offset that lets userspace > >> > specify the offset and disk to use when initiating a hibernate > >> > cycle. > >> > > >> > Also split up the parsing routine to re-use the same code > >> > for the /sys/power/resume and /sys/power/disk_offset parsing. > >> > > >> > Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> > >> > >> Well, IMO /sys/power/resume and /sys/power/disk_offset would be confusingly > >> similar after this patch. > > > > Yeah they do function pretty similarly. > > > >> > >> I wonder if adding a resume_offset sysfs attr to simply allow the value of > >> resume offset alone to be passed to the kernel at run time (in addition to > >> the command line) would work? > >> > >> Thanks! > > > > I guess what's your expected flow for how the disk gets selected though? Should > > the kernel be "guessing" which disk to use? > > > > Or should userspace be setting offset via /sys/power/resume_offset followed by > > disk in /sys/power/resume (which will show an error in syslog about no partition > > found) > > > > If the latter, > > Yes, the latter. > > > then I'd like to also modify the behavior to downgrade that missing > > hibernate partition to debug instead too. > > That's OK. OK thanks, I'll adjust per your recommendations.
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index 1e0d1da..9b66cd6 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -287,3 +287,46 @@ Description: Writing a "1" to this file enables the debug messages and writing a "0" (default) to it disables them. Reads from this file return the current value. + +What: /sys/power/disk_offset +Date: April 2018 +Contact: Mario Limonciello <mario.limonciello@dell.com> +Description: + This file is used for telling the kernel which disk partiion + and offset to use when hibernating the system. + + Reads from this file will display the current disk and + offset the kernel will be using on the next hibernation + attempt. + + Using this sysfs file will override any values that were + set using the kernel command line for resume disk or offset. + + Swap partition + -------------- + You can write the partition to this file with no offset. + + For example to use a swap partition you may write: + - "8:2" into the file. + or + - "/dev/sda2" into the file. + or + - "PARTUUID=a1386b9c-0d2a-41dd-bcf5-b9b19a863bfb" into the file + + Note: writing a partition with no offset will also reset the + offset to zero. + + Swap file + --------- + To use a swapfile you will need to write the partition + containing the swapfile along with a ";" and offset within + the partition that points to that file. + + For example to use a swapfile located in the disk you + may write: + - "8:2;38416" into the file. + or + - "/dev/sda2;38416" into the file + or + - "PARTUUID=a1386b9c-0d2a-41dd-bcf5-b9b19a863bfb;38416" into + the file diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index 9f2f942..539bb0b 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt @@ -24,8 +24,16 @@ Some warnings, first. * see the FAQ below for details. (This is not true for more traditional * power states like "standby", which normally don't turn USB off.) +Swap partition: You need to append resume=/dev/your_swap_partition to kernel command -line. Then you suspend by +line or specify it using /sys/power/disk_offset. + +Swap file: +If using a swapfile you can also specify a resume offset usin +resume_offset=<number> on the kernel command line or specify it after +the disk with a ";<offset>" in /sys/power/disk_offset. + +After preparing then you suspend by echo shutdown > /sys/power/disk; echo disk > /sys/power/state diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index a5c36e9..fc9dc7a 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -1025,33 +1025,69 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, power_attr(disk); +static int parse_device_input(const char *buf, size_t n, bool update_offset) +{ + char *start, *tok, *end; + int ret = -EINVAL; + dev_t res = 0; + int len = n; + + if (!len) + return ret; + if (buf[len-1] == '\n') + len--; + start = end = kstrndup(buf, len, GFP_KERNEL); + if (!end) + return -ENOMEM; + + tok = strsep(&end, ";"); + if (!tok) + goto out; + + res = name_to_dev_t(tok); + if (!res) + goto out; + ret = 0; + + /* keep behavior for /sys/power/resume */ + if (!update_offset) + goto out_name; + + /* If no offset specified, reset it */ + tok = strsep(&end, ";"); + if (!tok) { + swsusp_resume_block = 0; + goto out_name; + } + + ret = kstrtoull(tok, 0, (unsigned long long *) &swsusp_resume_block); + if (ret) + goto out; +out_name: + swsusp_resume_device = res; +out: + if (ret) + pr_warn("Unable to parse from %s (%d)", start, ret); + kfree(start); + return ret; +} + static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device), + return sprintf(buf, "%d:%d\n", MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); } static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t n) { - dev_t res; - int len = n; - char *name; + int rc = parse_device_input(buf, n, false); - if (len && buf[len-1] == '\n') - len--; - name = kstrndup(buf, len, GFP_KERNEL); - if (!name) - return -ENOMEM; - - res = name_to_dev_t(name); - kfree(name); - if (!res) - return -EINVAL; + if (rc < 0) + return rc; lock_system_sleep(); - swsusp_resume_device = res; unlock_system_sleep(); pr_info("Starting manual resume from disk\n"); noresume = 0; @@ -1061,6 +1097,27 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, power_attr(resume); +static ssize_t disk_offset_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%d:%d;%lu\n", MAJOR(swsusp_resume_device), + MINOR(swsusp_resume_device), swsusp_resume_block); +} + +static ssize_t disk_offset_store(struct kobject *kobj, + struct kobj_attribute *attr, const char *buf, + size_t n) +{ + int rc = parse_device_input(buf, n, true); + + if (rc < 0) + return rc; + + return n; +} + +power_attr(disk_offset); + static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { @@ -1106,6 +1163,7 @@ power_attr(reserved_size); static struct attribute * g[] = { &disk_attr.attr, + &disk_offset_attr.attr, &resume_attr.attr, &image_size_attr.attr, &reserved_size_attr.attr,
Currently the only way to specify a hibernate offset for a swap file is on the kernel command line. Add a new /sys/power/disk_offset that lets userspace specify the offset and disk to use when initiating a hibernate cycle. Also split up the parsing routine to re-use the same code for the /sys/power/resume and /sys/power/disk_offset parsing. Signed-off-by: Mario Limonciello <mario.limonciello@dell.com> --- Documentation/ABI/testing/sysfs-power | 43 +++++++++++++++++ Documentation/power/swsusp.txt | 10 +++- kernel/power/hibernate.c | 88 +++++++++++++++++++++++++++++------ 3 files changed, 125 insertions(+), 16 deletions(-)