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| author | Shaohua Li <shaohua.li@intel.com> | 2005-09-03 15:57:04 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@evo.osdl.org> | 2005-09-05 00:06:17 -0700 |
| commit | dd5d666b7995e542b7f81a4bb1c7ad634f4f6c51 (patch) | |
| tree | de010e4bd66681ec75657746d652eb89f08142b7 /kernel/power/disk.c | |
| parent | 6ed9fcec85d5ef0e34ea18affe95e4a246714565 (diff) | |
| download | blackbird-op-linux-dd5d666b7995e542b7f81a4bb1c7ad634f4f6c51.tar.gz blackbird-op-linux-dd5d666b7995e542b7f81a4bb1c7ad634f4f6c51.zip | |
[PATCH] swsusp: add locking to software_resume
It is trying to protect swsusp_resume_device and software_resume() from two
users banging it from userspace at the same time.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/power/disk.c')
| -rw-r--r-- | kernel/power/disk.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 664eb0469b6e..88beec6dcd11 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -233,9 +233,12 @@ static int software_resume(void) { int error; + down(&pm_sem); if (!swsusp_resume_device) { - if (!strlen(resume_file)) + if (!strlen(resume_file)) { + up(&pm_sem); return -ENOENT; + } swsusp_resume_device = name_to_dev_t(resume_file); pr_debug("swsusp: Resume From Partition %s\n", resume_file); } else { @@ -248,6 +251,7 @@ static int software_resume(void) * FIXME: If noresume is specified, we need to find the partition * and reset it back to normal swap space. */ + up(&pm_sem); return 0; } @@ -284,6 +288,8 @@ static int software_resume(void) Cleanup: unprepare_processes(); Done: + /* For success case, the suspend path will release the lock */ + up(&pm_sem); pr_debug("PM: Resume from disk failed.\n"); return 0; } @@ -390,7 +396,9 @@ static ssize_t resume_store(struct subsystem * subsys, const char * buf, size_t if (sscanf(buf, "%u:%u", &maj, &min) == 2) { res = MKDEV(maj,min); if (maj == MAJOR(res) && min == MINOR(res)) { + down(&pm_sem); swsusp_resume_device = res; + up(&pm_sem); printk("Attempting manual resume\n"); noresume = 0; software_resume(); |
