* [PATCH -mm 1/2] swsusp: Fix error paths in snapshot_open
2007-03-17 22:22 [PATCH -mm 0/2] swsusp: Use GFP_KERNEL for creating basic data structures Rafael J. Wysocki
@ 2007-03-17 22:24 ` Rafael J. Wysocki
2007-03-18 12:13 ` Pavel Machek
2007-03-17 22:27 ` [PATCH -mm 2/2] swsusp: Use GFP_KERNEL for creating basic data structures Rafael J. Wysocki
1 sibling, 1 reply; 4+ messages in thread
From: Rafael J. Wysocki @ 2007-03-17 22:24 UTC (permalink / raw)
To: Andrew Morton; +Cc: Pavel Machek, LKML
From: Rafael J. Wysocki <rjw@sisk.pl>
We forget to increase device_available if there's an error in snapshot_open(),
so the snapshot device cannot be open at all after snapshot_open() has returned
an error.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/user.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
Index: linux-2.6.21-rc4/kernel/power/user.c
===================================================================
--- linux-2.6.21-rc4.orig/kernel/power/user.c
+++ linux-2.6.21-rc4/kernel/power/user.c
@@ -49,12 +49,14 @@ static int snapshot_open(struct inode *i
if (!atomic_add_unless(&device_available, -1, 0))
return -EBUSY;
- if ((filp->f_flags & O_ACCMODE) == O_RDWR)
+ if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
+ atomic_inc(&device_available);
return -ENOSYS;
-
- if(create_basic_memory_bitmaps())
+ }
+ if(create_basic_memory_bitmaps()) {
+ atomic_inc(&device_available);
return -ENOMEM;
-
+ }
nonseekable_open(inode, filp);
data = &snapshot_state;
filp->private_data = data;
^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH -mm 2/2] swsusp: Use GFP_KERNEL for creating basic data structures
2007-03-17 22:22 [PATCH -mm 0/2] swsusp: Use GFP_KERNEL for creating basic data structures Rafael J. Wysocki
2007-03-17 22:24 ` [PATCH -mm 1/2] swsusp: Fix error paths in snapshot_open Rafael J. Wysocki
@ 2007-03-17 22:27 ` Rafael J. Wysocki
1 sibling, 0 replies; 4+ messages in thread
From: Rafael J. Wysocki @ 2007-03-17 22:27 UTC (permalink / raw)
To: Andrew Morton; +Cc: Pavel Machek, LKML
From: Rafael J. Wysocki <rjw@sisk.pl>
Make swsusp call create_basic_memory_bitmaps() before processes are frozen, so
that GFP_KERNEL allocations can be made in it. Additionally, ensure that the
swsusp's userland interface won't be used while either pm_suspend_disk()
or software_resume() is being executed.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/disk.c | 37 ++++++++++++++++++++++++++-----------
kernel/power/power.h | 3 +++
kernel/power/snapshot.c | 8 ++++----
kernel/power/user.c | 10 +++++-----
4 files changed, 38 insertions(+), 20 deletions(-)
Index: linux-2.6.21-rc4/kernel/power/disk.c
===================================================================
--- linux-2.6.21-rc4.orig/kernel/power/disk.c
+++ linux-2.6.21-rc4/kernel/power/disk.c
@@ -119,28 +119,33 @@ int pm_suspend_disk(void)
{
int error;
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0))
+ return -EBUSY;
+
+ /* Allocate memory management structures */
+ error = create_basic_memory_bitmaps();
+ if (error)
+ goto Exit;
+
error = prepare_processes();
if (error)
- return error;
+ goto Finish;
if (pm_disk_mode == PM_DISK_TESTPROC) {
printk("swsusp debug: Waiting for 5 seconds.\n");
mdelay(5000);
goto Thaw;
}
- /* Allocate memory management structures */
- error = create_basic_memory_bitmaps();
- if (error)
- goto Thaw;
/* Free memory before shutting down devices. */
error = swsusp_shrink_memory();
if (error)
- goto Finish;
+ goto Thaw;
error = platform_prepare();
if (error)
- goto Finish;
+ goto Thaw;
suspend_console();
error = device_suspend(PMSG_FREEZE);
@@ -175,7 +180,7 @@ int pm_suspend_disk(void)
power_down(pm_disk_mode);
else {
swsusp_free();
- goto Finish;
+ goto Thaw;
}
} else {
pr_debug("PM: Image restored successfully.\n");
@@ -188,10 +193,12 @@ int pm_suspend_disk(void)
platform_finish();
device_resume();
resume_console();
- Finish:
- free_basic_memory_bitmaps();
Thaw:
unprepare_processes();
+ Finish:
+ free_basic_memory_bitmaps();
+ Exit:
+ atomic_inc(&snapshot_device_available);
return error;
}
@@ -239,9 +246,15 @@ static int software_resume(void)
if (error)
goto Unlock;
+ /* The snapshot device should not be opened while we're running */
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ error = -EBUSY;
+ goto Unlock;
+ }
+
error = create_basic_memory_bitmaps();
if (error)
- goto Unlock;
+ goto Finish;
pr_debug("PM: Preparing processes for restore.\n");
error = prepare_processes();
@@ -287,6 +300,8 @@ static int software_resume(void)
unprepare_processes();
Done:
free_basic_memory_bitmaps();
+ Finish:
+ atomic_inc(&snapshot_device_available);
/* For success case, the suspend path will release the lock */
Unlock:
mutex_unlock(&pm_mutex);
Index: linux-2.6.21-rc4/kernel/power/power.h
===================================================================
--- linux-2.6.21-rc4.orig/kernel/power/power.h
+++ linux-2.6.21-rc4/kernel/power/power.h
@@ -141,6 +141,9 @@ struct resume_swap_area {
#define PMOPS_ENTER 2
#define PMOPS_FINISH 3
+/* If unset, the snapshot device cannot be open. */
+extern atomic_t snapshot_device_available;
+
/**
* The bitmap is used for tracing allocated swap pages
*
Index: linux-2.6.21-rc4/kernel/power/snapshot.c
===================================================================
--- linux-2.6.21-rc4.orig/kernel/power/snapshot.c
+++ linux-2.6.21-rc4/kernel/power/snapshot.c
@@ -733,19 +733,19 @@ int create_basic_memory_bitmaps(void)
BUG_ON(forbidden_pages_map || free_pages_map);
- bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_ATOMIC);
+ bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
if (!bm1)
return -ENOMEM;
- error = memory_bm_create(bm1, GFP_ATOMIC | __GFP_COLD, PG_ANY);
+ error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY);
if (error)
goto Free_first_object;
- bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_ATOMIC);
+ bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
if (!bm2)
goto Free_first_bitmap;
- error = memory_bm_create(bm2, GFP_ATOMIC | __GFP_COLD, PG_ANY);
+ error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY);
if (error)
goto Free_second_object;
Index: linux-2.6.21-rc4/kernel/power/user.c
===================================================================
--- linux-2.6.21-rc4.orig/kernel/power/user.c
+++ linux-2.6.21-rc4/kernel/power/user.c
@@ -40,21 +40,21 @@ static struct snapshot_data {
char platform_suspend;
} snapshot_state;
-static atomic_t device_available = ATOMIC_INIT(1);
+atomic_t snapshot_device_available = ATOMIC_INIT(1);
static int snapshot_open(struct inode *inode, struct file *filp)
{
struct snapshot_data *data;
- if (!atomic_add_unless(&device_available, -1, 0))
+ if (!atomic_add_unless(&snapshot_device_available, -1, 0))
return -EBUSY;
if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
- atomic_inc(&device_available);
+ atomic_inc(&snapshot_device_available);
return -ENOSYS;
}
if(create_basic_memory_bitmaps()) {
- atomic_inc(&device_available);
+ atomic_inc(&snapshot_device_available);
return -ENOMEM;
}
nonseekable_open(inode, filp);
@@ -92,7 +92,7 @@ static int snapshot_release(struct inode
enable_nonboot_cpus();
mutex_unlock(&pm_mutex);
}
- atomic_inc(&device_available);
+ atomic_inc(&snapshot_device_available);
return 0;
}
^ permalink raw reply [flat|nested] 4+ messages in thread