From 03afed8bc296fa70186ba832c1126228bb992465 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 21 Nov 2011 12:32:24 -0800 Subject: freezer: clean up freeze_processes() failure path freeze_processes() failure path is rather messy. Freezing is canceled for workqueues and tasks which aren't frozen yet but frozen tasks are left alone and should be thawed by the caller and of course some callers (xen and kexec) didn't do it. This patch updates __thaw_task() to handle cancelation correctly and makes freeze_processes() and freeze_kernel_threads() call thaw_processes() on failure instead so that the system is fully thawed on failure. Unnecessary [suspend_]thaw_processes() calls are removed from kernel/power/hibernate.c, suspend.c and user.c. While at it, restructure error checking if clause in suspend_prepare() to be less weird. -v2: Srivatsa spotted missing removal of suspend_thaw_processes() in suspend_prepare() and error in commit message. Updated. Signed-off-by: Tejun Heo Acked-by: Srivatsa S. Bhat --- kernel/power/user.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index 6d8f535c2b88..7cc3f5bc5c24 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -257,10 +257,8 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, break; error = freeze_processes(); - if (error) { - thaw_processes(); + if (error) usermodehelper_enable(); - } if (!error) data->frozen = 1; break; -- cgit v1.2.3 From 97819a26224f019e73d88bb2fd4eb5a614860461 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Thu, 1 Dec 2011 22:33:10 +0100 Subject: PM / Hibernate: Thaw processes in SNAPSHOT_CREATE_IMAGE ioctl test path Commit 2aede851ddf08666f68ffc17be446420e9d2a056 (PM / Hibernate: Freeze kernel threads after preallocating memory) moved the freezing of kernel threads to hibernation_snapshot() function. So now, if the call to hibernation_snapshot() returns early due to a successful hibernation test, the caller has to thaw processes to ensure that the system gets back to its original state. But in SNAPSHOT_CREATE_IMAGE hibernation ioctl, the caller does not thaw processes in case hibernation_snapshot() returned due to a successful freezer test. Fix this issue. But note we still send the value of 'in_suspend' (which is now 0) to userspace, because we are not in an error path per-se, and moreover, the value of in_suspend correctly depicts the situation here. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index 6d8f535c2b88..e2aff0fc2697 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -283,10 +283,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, } pm_restore_gfp_mask(); error = hibernation_snapshot(data->platform_support); - if (!error) + if (!error) { error = put_user(in_suspend, (int __user *)arg); - if (!error) - data->ready = 1; + if (!error && !freezer_test_done) + data->ready = 1; + if (freezer_test_done) { + freezer_test_done = false; + thaw_processes(); + } + } break; case SNAPSHOT_ATOMIC_RESTORE: -- cgit v1.2.3 From e5b16746f0f2d6883c226af52d90904ce0f7eee8 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Sat, 3 Dec 2011 00:20:30 +0100 Subject: PM / Hibernate: Replace unintuitive 'if' condition in kernel/power/user.c with 'else' In the snapshot_ioctl() function, under SNAPSHOT_FREEZE, the code below freeze_processes() is a bit unintuitive. Improve it by replacing the second 'if' condition with an 'else' clause. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index c202e2e1a2d5..06ea33df8560 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -259,7 +259,7 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, error = freeze_processes(); if (error) usermodehelper_enable(); - if (!error) + else data->frozen = 1; break; -- cgit v1.2.3 From bcda53faf5814c0c6025a0bd47108adfcbe9f199 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Wed, 7 Dec 2011 22:29:54 +0100 Subject: PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep() Using [un]lock_system_sleep() is safer than directly using mutex_[un]lock() on 'pm_mutex', since the latter could lead to freezing failures. Hence convert all the present users of mutex_[un]lock(&pm_mutex) to use these safe APIs instead. Suggested-by: Tejun Heo Signed-off-by: Srivatsa S. Bhat Reviewed-by: Simon Horman Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index 06ea33df8560..98ade217da6c 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -71,7 +71,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) struct snapshot_data *data; int error; - mutex_lock(&pm_mutex); + lock_system_sleep(); if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { error = -EBUSY; @@ -123,7 +123,7 @@ static int snapshot_open(struct inode *inode, struct file *filp) data->platform_support = 0; Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return error; } @@ -132,7 +132,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) { struct snapshot_data *data; - mutex_lock(&pm_mutex); + lock_system_sleep(); swsusp_free(); free_basic_memory_bitmaps(); @@ -146,7 +146,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) PM_POST_HIBERNATION : PM_POST_RESTORE); atomic_inc(&snapshot_device_available); - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return 0; } @@ -158,7 +158,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, ssize_t res; loff_t pg_offp = *offp & ~PAGE_MASK; - mutex_lock(&pm_mutex); + lock_system_sleep(); data = filp->private_data; if (!data->ready) { @@ -179,7 +179,7 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, *offp += res; Unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return res; } @@ -191,7 +191,7 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, ssize_t res; loff_t pg_offp = *offp & ~PAGE_MASK; - mutex_lock(&pm_mutex); + lock_system_sleep(); data = filp->private_data; @@ -208,7 +208,7 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, if (res > 0) *offp += res; unlock: - mutex_unlock(&pm_mutex); + unlock_system_sleep(); return res; } -- cgit v1.2.3 From cf007e3526a785a95a738d5a8fba44f1f4fe33e0 Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Thu, 8 Dec 2011 23:42:53 +0100 Subject: PM / Hibernate: Remove deprecated hibernation snapshot ioctls Several snapshot ioctls were marked for removal quite some time ago, since they were deprecated. Remove them. Suggested-by: Rafael J. Wysocki Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 87 ----------------------------------------------------- 1 file changed, 87 deletions(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index 98ade217da6c..78bdb4404aab 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -30,28 +30,6 @@ #include "power.h" -/* - * NOTE: The SNAPSHOT_SET_SWAP_FILE and SNAPSHOT_PMOPS ioctls are obsolete and - * will be removed in the future. They are only preserved here for - * compatibility with existing userland utilities. - */ -#define SNAPSHOT_SET_SWAP_FILE _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int) -#define SNAPSHOT_PMOPS _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int) - -#define PMOPS_PREPARE 1 -#define PMOPS_ENTER 2 -#define PMOPS_FINISH 3 - -/* - * NOTE: The following ioctl definitions are wrong and have been replaced with - * correct ones. They are only preserved here for compatibility with existing - * userland utilities and will be removed in the future. - */ -#define SNAPSHOT_ATOMIC_SNAPSHOT _IOW(SNAPSHOT_IOC_MAGIC, 3, void *) -#define SNAPSHOT_SET_IMAGE_SIZE _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long) -#define SNAPSHOT_AVAIL_SWAP _IOR(SNAPSHOT_IOC_MAGIC, 7, void *) -#define SNAPSHOT_GET_SWAP_PAGE _IOR(SNAPSHOT_IOC_MAGIC, 8, void *) - #define SNAPSHOT_MINOR 231 @@ -213,15 +191,6 @@ unlock: return res; } -static void snapshot_deprecated_ioctl(unsigned int cmd) -{ - if (printk_ratelimit()) - printk(KERN_NOTICE "%pf: ioctl '%.8x' is deprecated and will " - "be removed soon, update your suspend-to-disk " - "utilities\n", - __builtin_return_address(0), cmd); -} - static long snapshot_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { @@ -272,8 +241,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, data->frozen = 0; break; - case SNAPSHOT_ATOMIC_SNAPSHOT: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_CREATE_IMAGE: if (data->mode != O_RDONLY || !data->frozen || data->ready) { error = -EPERM; @@ -308,8 +275,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, data->ready = 0; break; - case SNAPSHOT_SET_IMAGE_SIZE: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_PREF_IMAGE_SIZE: image_size = arg; break; @@ -324,16 +289,12 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, error = put_user(size, (loff_t __user *)arg); break; - case SNAPSHOT_AVAIL_SWAP: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_AVAIL_SWAP_SIZE: size = count_swap_pages(data->swap, 1); size <<= PAGE_SHIFT; error = put_user(size, (loff_t __user *)arg); break; - case SNAPSHOT_GET_SWAP_PAGE: - snapshot_deprecated_ioctl(cmd); case SNAPSHOT_ALLOC_SWAP_PAGE: if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { error = -ENODEV; @@ -356,27 +317,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, free_all_swap_pages(data->swap); break; - case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */ - snapshot_deprecated_ioctl(cmd); - if (!swsusp_swap_in_use()) { - /* - * User space encodes device types as two-byte values, - * so we need to recode them - */ - if (old_decode_dev(arg)) { - data->swap = swap_type_of(old_decode_dev(arg), - 0, NULL); - if (data->swap < 0) - error = -ENODEV; - } else { - data->swap = -1; - error = -EINVAL; - } - } else { - error = -EPERM; - } - break; - case SNAPSHOT_S2RAM: if (!data->frozen) { error = -EPERM; @@ -399,33 +339,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, error = hibernation_platform_enter(); break; - case SNAPSHOT_PMOPS: /* This ioctl is deprecated */ - snapshot_deprecated_ioctl(cmd); - error = -EINVAL; - - switch (arg) { - - case PMOPS_PREPARE: - data->platform_support = 1; - error = 0; - break; - - case PMOPS_ENTER: - if (data->platform_support) - error = hibernation_platform_enter(); - break; - - case PMOPS_FINISH: - if (data->platform_support) - error = 0; - break; - - default: - printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg); - - } - break; - case SNAPSHOT_SET_SWAP_AREA: if (swsusp_swap_in_use()) { error = -EPERM; -- cgit v1.2.3 From c336078bf65c4d38caa9a4b8b7b7261c778e622c Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Tue, 27 Dec 2011 22:54:52 +0100 Subject: PM / Hibernate: Implement compat_ioctl for /dev/snapshot This allows uswsusp built for i386 to run on an x86_64 kernel (tested with Debian package version 1.0+20110509-2). References: http://bugs.debian.org/502816 Signed-off-by: Ben Hutchings Signed-off-by: Rafael J. Wysocki --- kernel/power/user.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index 78bdb4404aab..6b1ab7a88522 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -380,6 +381,66 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, return error; } +#ifdef CONFIG_COMPAT + +struct compat_resume_swap_area { + compat_loff_t offset; + u32 dev; +} __packed; + +static long +snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + BUILD_BUG_ON(sizeof(loff_t) != sizeof(compat_loff_t)); + + switch (cmd) { + case SNAPSHOT_GET_IMAGE_SIZE: + case SNAPSHOT_AVAIL_SWAP_SIZE: + case SNAPSHOT_ALLOC_SWAP_PAGE: { + compat_loff_t __user *uoffset = compat_ptr(arg); + loff_t offset; + mm_segment_t old_fs; + int err; + + old_fs = get_fs(); + set_fs(KERNEL_DS); + err = snapshot_ioctl(file, cmd, (unsigned long) &offset); + set_fs(old_fs); + if (!err && put_user(offset, uoffset)) + err = -EFAULT; + return err; + } + + case SNAPSHOT_CREATE_IMAGE: + return snapshot_ioctl(file, cmd, + (unsigned long) compat_ptr(arg)); + + case SNAPSHOT_SET_SWAP_AREA: { + struct compat_resume_swap_area __user *u_swap_area = + compat_ptr(arg); + struct resume_swap_area swap_area; + mm_segment_t old_fs; + int err; + + err = get_user(swap_area.offset, &u_swap_area->offset); + err |= get_user(swap_area.dev, &u_swap_area->dev); + if (err) + return -EFAULT; + old_fs = get_fs(); + set_fs(KERNEL_DS); + err = snapshot_ioctl(file, SNAPSHOT_SET_SWAP_AREA, + (unsigned long) &swap_area); + set_fs(old_fs); + return err; + } + + default: + return snapshot_ioctl(file, cmd, arg); + } +} + +#endif /* CONFIG_COMPAT */ + static const struct file_operations snapshot_fops = { .open = snapshot_open, .release = snapshot_release, @@ -387,6 +448,9 @@ static const struct file_operations snapshot_fops = { .write = snapshot_write, .llseek = no_llseek, .unlocked_ioctl = snapshot_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = snapshot_compat_ioctl, +#endif }; static struct miscdevice snapshot_device = { -- cgit v1.2.3 From 181e9bdef37bfcaa41f3ab6c948a2a0d60a268b5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 29 Jan 2012 20:35:52 +0100 Subject: PM / Hibernate: Fix s2disk regression related to freezing workqueues Commit 2aede851ddf08666f68ffc17be446420e9d2a056 PM / Hibernate: Freeze kernel threads after preallocating memory introduced a mechanism by which kernel threads were frozen after the preallocation of hibernate image memory to avoid problems with frozen kernel threads not responding to memory freeing requests. However, it overlooked the s2disk code path in which the SNAPSHOT_CREATE_IMAGE ioctl was run directly after SNAPSHOT_FREE, which caused freeze_workqueues_begin() to BUG(), because it saw that worqueues had been already frozen. Although in principle this issue might be addressed by removing the relevant BUG_ON() from freeze_workqueues_begin(), that would reintroduce the very problem that commit 2aede851ddf08666f68ffc17be4 attempted to avoid into that particular code path. For this reason, to fix the issue at hand, introduce thaw_kernel_threads() and make the SNAPSHOT_FREE ioctl execute it. Special thanks to Srivatsa S. Bhat for detailed analysis of the problem. Reported-and-tested-by: Jiri Slaby Signed-off-by: Rafael J. Wysocki Acked-by: Srivatsa S. Bhat Cc: stable@kernel.org --- kernel/power/user.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index 6b1ab7a88522..e5a21a857302 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -274,6 +274,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, swsusp_free(); memset(&data->handle, 0, sizeof(struct snapshot_handle)); data->ready = 0; + /* + * It is necessary to thaw kernel threads here, because + * SNAPSHOT_CREATE_IMAGE may be invoked directly after + * SNAPSHOT_FREE. In that case, if kernel threads were not + * thawed, the preallocation of memory carried out by + * hibernation_snapshot() might run into problems (i.e. it + * might fail or even deadlock). + */ + thaw_kernel_threads(); break; case SNAPSHOT_PREF_IMAGE_SIZE: -- cgit v1.2.3 From fe9161db2e6053da21e4649d77bbefaf3030b11d Mon Sep 17 00:00:00 2001 From: "Srivatsa S. Bhat" Date: Wed, 1 Feb 2012 22:16:36 +0100 Subject: PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path In the SNAPSHOT_CREATE_IMAGE ioctl, if the call to hibernation_snapshot() fails, the frozen tasks are not thawed. And in the case of success, if we happen to exit due to a successful freezer test, all tasks (including those of userspace) are thawed, whereas actually we should have thawed only the kernel threads at that point. Fix both these issues. Signed-off-by: Srivatsa S. Bhat Signed-off-by: Rafael J. Wysocki Cc: stable@vger.kernel.org --- kernel/power/user.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'kernel/power/user.c') diff --git a/kernel/power/user.c b/kernel/power/user.c index e5a21a857302..3e100075b13c 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -249,13 +249,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, } pm_restore_gfp_mask(); error = hibernation_snapshot(data->platform_support); - if (!error) { + if (error) { + thaw_kernel_threads(); + } else { error = put_user(in_suspend, (int __user *)arg); if (!error && !freezer_test_done) data->ready = 1; if (freezer_test_done) { freezer_test_done = false; - thaw_processes(); + thaw_kernel_threads(); } } break; -- cgit v1.2.3