]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - kernel/power/user.c
snapshot: Use pm_mutex for mutual exclusion
[linux-2.6-omap-h63xx.git] / kernel / power / user.c
index 5bd321bcbb75f06031d6ede749cad599c251373c..a6332a3132620b4563e3be8a0fbfb9639b1e5405 100644 (file)
 #include <linux/console.h>
 #include <linux/cpu.h>
 #include <linux/freezer.h>
+#include <linux/smp_lock.h>
 
 #include <asm/uaccess.h>
 
 #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
 
 static struct snapshot_data {
@@ -36,7 +60,7 @@ static struct snapshot_data {
        int mode;
        char frozen;
        char ready;
-       char platform_suspend;
+       char platform_support;
 } snapshot_state;
 
 atomic_t snapshot_device_available = ATOMIC_INIT(1);
@@ -44,17 +68,24 @@ atomic_t snapshot_device_available = ATOMIC_INIT(1);
 static int snapshot_open(struct inode *inode, struct file *filp)
 {
        struct snapshot_data *data;
+       int error;
 
-       if (!atomic_add_unless(&snapshot_device_available, -1, 0))
-               return -EBUSY;
+       mutex_lock(&pm_mutex);
+
+       if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+               error = -EBUSY;
+               goto Unlock;
+       }
 
        if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
                atomic_inc(&snapshot_device_available);
-               return -ENOSYS;
+               error = -ENOSYS;
+               goto Unlock;
        }
        if(create_basic_memory_bitmaps()) {
                atomic_inc(&snapshot_device_available);
-               return -ENOMEM;
+               error = -ENOMEM;
+               goto Unlock;
        }
        nonseekable_open(inode, filp);
        data = &snapshot_state;
@@ -64,31 +95,46 @@ static int snapshot_open(struct inode *inode, struct file *filp)
                data->swap = swsusp_resume_device ?
                        swap_type_of(swsusp_resume_device, 0, NULL) : -1;
                data->mode = O_RDONLY;
+               error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
+               if (error)
+                       pm_notifier_call_chain(PM_POST_RESTORE);
        } else {
                data->swap = -1;
                data->mode = O_WRONLY;
+               error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
+               if (error)
+                       pm_notifier_call_chain(PM_POST_HIBERNATION);
        }
+       if (error)
+               atomic_inc(&snapshot_device_available);
        data->frozen = 0;
        data->ready = 0;
-       data->platform_suspend = 0;
+       data->platform_support = 0;
 
-       return 0;
+ Unlock:
+       mutex_unlock(&pm_mutex);
+
+       return error;
 }
 
 static int snapshot_release(struct inode *inode, struct file *filp)
 {
        struct snapshot_data *data;
 
+       mutex_lock(&pm_mutex);
+
        swsusp_free();
        free_basic_memory_bitmaps();
        data = filp->private_data;
        free_all_swap_pages(data->swap);
-       if (data->frozen) {
-               mutex_lock(&pm_mutex);
+       if (data->frozen)
                thaw_processes();
-               mutex_unlock(&pm_mutex);
-       }
+       pm_notifier_call_chain(data->mode == O_WRONLY ?
+                       PM_POST_HIBERNATION : PM_POST_RESTORE);
        atomic_inc(&snapshot_device_available);
+
+       mutex_unlock(&pm_mutex);
+
        return 0;
 }
 
@@ -98,9 +144,13 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
        struct snapshot_data *data;
        ssize_t res;
 
+       mutex_lock(&pm_mutex);
+
        data = filp->private_data;
-       if (!data->ready)
-               return -ENODATA;
+       if (!data->ready) {
+               res = -ENODATA;
+               goto Unlock;
+       }
        res = snapshot_read_next(&data->handle, count);
        if (res > 0) {
                if (copy_to_user(buf, data_of(data->handle), res))
@@ -108,6 +158,10 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
                else
                        *offp = data->handle.offset;
        }
+
+ Unlock:
+       mutex_unlock(&pm_mutex);
+
        return res;
 }
 
@@ -117,6 +171,8 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
        struct snapshot_data *data;
        ssize_t res;
 
+       mutex_lock(&pm_mutex);
+
        data = filp->private_data;
        res = snapshot_write_next(&data->handle, count);
        if (res > 0) {
@@ -125,15 +181,18 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
                else
                        *offp = data->handle.offset;
        }
+
+       mutex_unlock(&pm_mutex);
+
        return res;
 }
 
-static int snapshot_ioctl(struct inode *inode, struct file *filp,
-                          unsigned int cmd, unsigned long arg)
+static long snapshot_ioctl(struct file *filp, unsigned int cmd,
+                                                       unsigned long arg)
 {
        int error = 0;
        struct snapshot_data *data;
-       loff_t avail;
+       loff_t size;
        sector_t offset;
 
        if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
@@ -143,6 +202,9 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;
 
+       if (!mutex_trylock(&pm_mutex))
+               return -EBUSY;
+
        data = filp->private_data;
 
        switch (cmd) {
@@ -150,20 +212,13 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
        case SNAPSHOT_FREEZE:
                if (data->frozen)
                        break;
-               mutex_lock(&pm_mutex);
-               error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
-               if (!error) {
-                       printk("Syncing filesystems ... ");
-                       sys_sync();
-                       printk("done.\n");
-
-                       error = freeze_processes();
-                       if (error)
-                               thaw_processes();
-               }
+               printk("Syncing filesystems ... ");
+               sys_sync();
+               printk("done.\n");
+
+               error = freeze_processes();
                if (error)
-                       pm_notifier_call_chain(PM_POST_HIBERNATION);
-               mutex_unlock(&pm_mutex);
+                       thaw_processes();
                if (!error)
                        data->frozen = 1;
                break;
@@ -171,21 +226,19 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
        case SNAPSHOT_UNFREEZE:
                if (!data->frozen || data->ready)
                        break;
-               mutex_lock(&pm_mutex);
                thaw_processes();
-               pm_notifier_call_chain(PM_POST_HIBERNATION);
-               mutex_unlock(&pm_mutex);
                data->frozen = 0;
                break;
 
+       case SNAPSHOT_CREATE_IMAGE:
        case SNAPSHOT_ATOMIC_SNAPSHOT:
                if (data->mode != O_RDONLY || !data->frozen  || data->ready) {
                        error = -EPERM;
                        break;
                }
-               error = hibernation_snapshot(data->platform_suspend);
+               error = hibernation_snapshot(data->platform_support);
                if (!error)
-                       error = put_user(in_suspend, (unsigned int __user *)arg);
+                       error = put_user(in_suspend, (int __user *)arg);
                if (!error)
                        data->ready = 1;
                break;
@@ -197,7 +250,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        error = -EPERM;
                        break;
                }
-               error = hibernation_restore(data->platform_suspend);
+               error = hibernation_restore(data->platform_support);
                break;
 
        case SNAPSHOT_FREE:
@@ -206,16 +259,29 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                data->ready = 0;
                break;
 
+       case SNAPSHOT_PREF_IMAGE_SIZE:
        case SNAPSHOT_SET_IMAGE_SIZE:
                image_size = arg;
                break;
 
+       case SNAPSHOT_GET_IMAGE_SIZE:
+               if (!data->ready) {
+                       error = -ENODATA;
+                       break;
+               }
+               size = snapshot_get_image_size();
+               size <<= PAGE_SHIFT;
+               error = put_user(size, (loff_t __user *)arg);
+               break;
+
+       case SNAPSHOT_AVAIL_SWAP_SIZE:
        case SNAPSHOT_AVAIL_SWAP:
-               avail = count_swap_pages(data->swap, 1);
-               avail <<= PAGE_SHIFT;
-               error = put_user(avail, (loff_t __user *)arg);
+               size = count_swap_pages(data->swap, 1);
+               size <<= PAGE_SHIFT;
+               error = put_user(size, (loff_t __user *)arg);
                break;
 
+       case SNAPSHOT_ALLOC_SWAP_PAGE:
        case SNAPSHOT_GET_SWAP_PAGE:
                if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
                        error = -ENODEV;
@@ -224,7 +290,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                offset = alloc_swapdev_block(data->swap);
                if (offset) {
                        offset <<= PAGE_SHIFT;
-                       error = put_user(offset, (sector_t __user *)arg);
+                       error = put_user(offset, (loff_t __user *)arg);
                } else {
                        error = -ENOSPC;
                }
@@ -238,7 +304,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                free_all_swap_pages(data->swap);
                break;
 
-       case SNAPSHOT_SET_SWAP_FILE:
+       case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */
                if (!swsusp_swap_in_use()) {
                        /*
                         * User space encodes device types as two-byte values,
@@ -263,38 +329,40 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        error = -EPERM;
                        break;
                }
-               if (!mutex_trylock(&pm_mutex)) {
-                       error = -EBUSY;
-                       break;
-               }
                /*
                 * Tasks are frozen and the notifiers have been called with
                 * PM_HIBERNATION_PREPARE
                 */
                error = suspend_devices_and_enter(PM_SUSPEND_MEM);
-               mutex_unlock(&pm_mutex);
                break;
 
-       case SNAPSHOT_PMOPS:
+       case SNAPSHOT_PLATFORM_SUPPORT:
+               data->platform_support = !!arg;
+               break;
+
+       case SNAPSHOT_POWER_OFF:
+               if (data->platform_support)
+                       error = hibernation_platform_enter();
+               break;
+
+       case SNAPSHOT_PMOPS: /* This ioctl is deprecated */
                error = -EINVAL;
 
                switch (arg) {
 
                case PMOPS_PREPARE:
-                       data->platform_suspend = 1;
+                       data->platform_support = 1;
                        error = 0;
                        break;
 
                case PMOPS_ENTER:
-                       if (data->platform_suspend)
+                       if (data->platform_support)
                                error = hibernation_platform_enter();
-
                        break;
 
                case PMOPS_FINISH:
-                       if (data->platform_suspend)
+                       if (data->platform_support)
                                error = 0;
-
                        break;
 
                default:
@@ -339,6 +407,8 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
 
        }
 
+       mutex_unlock(&pm_mutex);
+
        return error;
 }
 
@@ -348,7 +418,7 @@ static const struct file_operations snapshot_fops = {
        .read = snapshot_read,
        .write = snapshot_write,
        .llseek = no_llseek,
-       .ioctl = snapshot_ioctl,
+       .unlocked_ioctl = snapshot_ioctl,
 };
 
 static struct miscdevice snapshot_device = {