kfifo: document everywhere that size has to be power of two
[safe/jmp/linux-2.6] / kernel / power / user.c
index 5a8d060..bf0014d 100644 (file)
@@ -11,6 +11,7 @@
 
 #include <linux/suspend.h>
 #include <linux/syscalls.h>
+#include <linux/reboot.h>
 #include <linux/string.h>
 #include <linux/device.h>
 #include <linux/miscdevice.h>
 #include <linux/swapops.h>
 #include <linux/pm.h>
 #include <linux/fs.h>
+#include <linux/console.h>
+#include <linux/cpu.h>
+#include <linux/freezer.h>
+#include <scsi/scsi_scan.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 {
        struct snapshot_handle handle;
        int swap;
-       struct bitmap_page *bitmap;
        int mode;
        char frozen;
        char ready;
+       char platform_support;
 } 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;
+       int error;
 
-       if (!atomic_add_unless(&device_available, -1, 0))
-               return -EBUSY;
+       mutex_lock(&pm_mutex);
 
-       if ((filp->f_flags & O_ACCMODE) == O_RDWR)
-               return -ENOSYS;
+       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);
+               error = -ENOSYS;
+               goto Unlock;
+       }
+       if(create_basic_memory_bitmaps()) {
+               atomic_inc(&snapshot_device_available);
+               error = -ENOMEM;
+               goto Unlock;
+       }
        nonseekable_open(inode, filp);
        data = &snapshot_state;
        filp->private_data = data;
        memset(&data->handle, 0, sizeof(struct snapshot_handle));
        if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
-               data->swap = swsusp_resume_device ? swap_type_of(swsusp_resume_device) : -1;
+               /* Hibernating.  The image device should be accessible. */
+               data->swap = swsusp_resume_device ?
+                       swap_type_of(swsusp_resume_device, 0, NULL) : -1;
                data->mode = O_RDONLY;
+               error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
+               if (error)
+                       pm_notifier_call_chain(PM_POST_HIBERNATION);
        } else {
+               /*
+                * Resuming.  We may need to wait for the image device to
+                * appear.
+                */
+               wait_for_device_probe();
+               scsi_complete_async_scans();
+
                data->swap = -1;
                data->mode = O_WRONLY;
+               error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
+               if (error)
+                       pm_notifier_call_chain(PM_POST_RESTORE);
        }
-       data->bitmap = NULL;
+       if (error)
+               atomic_inc(&snapshot_device_available);
        data->frozen = 0;
        data->ready = 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, data->bitmap);
-       free_bitmap(data->bitmap);
-       if (data->frozen) {
-               down(&pm_sem);
+       free_all_swap_pages(data->swap);
+       if (data->frozen)
                thaw_processes();
-               enable_nonboot_cpus();
-               up(&pm_sem);
-       }
-       atomic_inc(&device_available);
+       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;
 }
 
@@ -89,7 +152,13 @@ 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) {
+               res = -ENODATA;
+               goto Unlock;
+       }
        res = snapshot_read_next(&data->handle, count);
        if (res > 0) {
                if (copy_to_user(buf, data_of(data->handle), res))
@@ -97,6 +166,10 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf,
                else
                        *offp = data->handle.offset;
        }
+
+ Unlock:
+       mutex_unlock(&pm_mutex);
+
        return res;
 }
 
@@ -106,6 +179,8 @@ 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) {
@@ -114,15 +189,19 @@ 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 offset, avail;
+       loff_t size;
+       sector_t offset;
 
        if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
                return -ENOTTY;
@@ -131,6 +210,9 @@ 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) {
@@ -138,66 +220,53 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
        case SNAPSHOT_FREEZE:
                if (data->frozen)
                        break;
-               down(&pm_sem);
-               disable_nonboot_cpus();
-               if (freeze_processes()) {
+
+               printk("Syncing filesystems ... ");
+               sys_sync();
+               printk("done.\n");
+
+               error = usermodehelper_disable();
+               if (error)
+                       break;
+
+               error = freeze_processes();
+               if (error) {
                        thaw_processes();
-                       enable_nonboot_cpus();
-                       error = -EBUSY;
+                       usermodehelper_enable();
                }
-               up(&pm_sem);
                if (!error)
                        data->frozen = 1;
                break;
 
        case SNAPSHOT_UNFREEZE:
-               if (!data->frozen)
+               if (!data->frozen || data->ready)
                        break;
-               down(&pm_sem);
                thaw_processes();
-               enable_nonboot_cpus();
-               up(&pm_sem);
+               usermodehelper_enable();
                data->frozen = 0;
                break;
 
+       case SNAPSHOT_CREATE_IMAGE:
        case SNAPSHOT_ATOMIC_SNAPSHOT:
                if (data->mode != O_RDONLY || !data->frozen  || data->ready) {
                        error = -EPERM;
                        break;
                }
-               down(&pm_sem);
-               /* Free memory before shutting down devices. */
-               error = swsusp_shrink_memory();
-               if (!error) {
-                       error = device_suspend(PMSG_FREEZE);
-                       if (!error) {
-                               in_suspend = 1;
-                               error = swsusp_suspend();
-                               device_resume();
-                       }
-               }
-               up(&pm_sem);
+               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;
 
        case SNAPSHOT_ATOMIC_RESTORE:
+               snapshot_write_finalize(&data->handle);
                if (data->mode != O_WRONLY || !data->frozen ||
                    !snapshot_image_loaded(&data->handle)) {
                        error = -EPERM;
                        break;
                }
-               down(&pm_sem);
-               pm_prepare_console();
-               error = device_suspend(PMSG_PRETHAW);
-               if (!error) {
-                       error = swsusp_resume();
-                       device_resume();
-               }
-               pm_restore_console();
-               up(&pm_sem);
+               error = hibernation_restore(data->platform_support);
                break;
 
        case SNAPSHOT_FREE:
@@ -206,29 +275,35 @@ 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;
                        break;
                }
-               if (!data->bitmap) {
-                       data->bitmap = alloc_bitmap(count_swap_pages(data->swap, 0));
-                       if (!data->bitmap) {
-                               error = -ENOMEM;
-                               break;
-                       }
-               }
-               offset = alloc_swap_page(data->swap, data->bitmap);
+               offset = alloc_swapdev_block(data->swap);
                if (offset) {
                        offset <<= PAGE_SHIFT;
                        error = put_user(offset, (loff_t __user *)arg);
@@ -242,19 +317,18 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        error = -ENODEV;
                        break;
                }
-               free_all_swap_pages(data->swap, data->bitmap);
-               free_bitmap(data->bitmap);
-               data->bitmap = NULL;
+               free_all_swap_pages(data->swap);
                break;
 
-       case SNAPSHOT_SET_SWAP_FILE:
-               if (!data->bitmap) {
+       case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */
+               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));
+                               data->swap = swap_type_of(old_decode_dev(arg),
+                                                       0, NULL);
                                if (data->swap < 0)
                                        error = -ENODEV;
                        } else {
@@ -271,35 +345,77 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
                        error = -EPERM;
                        break;
                }
+               /*
+                * Tasks are frozen and the notifiers have been called with
+                * PM_HIBERNATION_PREPARE
+                */
+               error = suspend_devices_and_enter(PM_SUSPEND_MEM);
+               break;
 
-               if (down_trylock(&pm_sem)) {
-                       error = -EBUSY;
+       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_support = 1;
+                       error = 0;
                        break;
-               }
 
-               if (pm_ops->prepare) {
-                       error = pm_ops->prepare(PM_SUSPEND_MEM);
-                       if (error)
-                               goto OutS3;
-               }
+               case PMOPS_ENTER:
+                       if (data->platform_support)
+                               error = hibernation_platform_enter();
+                       break;
 
-               /* Put devices to sleep */
-               error = device_suspend(PMSG_SUSPEND);
-               if (error) {
-                       printk(KERN_ERR "Failed to suspend some devices.\n");
-               } else {
-                       /* Enter S3, system is already frozen */
-                       suspend_enter(PM_SUSPEND_MEM);
+               case PMOPS_FINISH:
+                       if (data->platform_support)
+                               error = 0;
+                       break;
+
+               default:
+                       printk(KERN_ERR "SNAPSHOT_PMOPS: invalid argument %ld\n", arg);
 
-                       /* Wake up devices */
-                       device_resume();
                }
+               break;
+
+       case SNAPSHOT_SET_SWAP_AREA:
+               if (swsusp_swap_in_use()) {
+                       error = -EPERM;
+               } else {
+                       struct resume_swap_area swap_area;
+                       dev_t swdev;
 
-               if (pm_ops->finish)
-                       pm_ops->finish(PM_SUSPEND_MEM);
+                       error = copy_from_user(&swap_area, (void __user *)arg,
+                                       sizeof(struct resume_swap_area));
+                       if (error) {
+                               error = -EFAULT;
+                               break;
+                       }
 
-OutS3:
-               up(&pm_sem);
+                       /*
+                        * User space encodes device types as two-byte values,
+                        * so we need to recode them
+                        */
+                       swdev = old_decode_dev(swap_area.dev);
+                       if (swdev) {
+                               offset = swap_area.offset;
+                               data->swap = swap_type_of(swdev, offset, NULL);
+                               if (data->swap < 0)
+                                       error = -ENODEV;
+                       } else {
+                               data->swap = -1;
+                               error = -EINVAL;
+                       }
+               }
                break;
 
        default:
@@ -307,16 +423,18 @@ OutS3:
 
        }
 
+       mutex_unlock(&pm_mutex);
+
        return error;
 }
 
-static struct file_operations snapshot_fops = {
+static const struct file_operations snapshot_fops = {
        .open = snapshot_open,
        .release = snapshot_release,
        .read = snapshot_read,
        .write = snapshot_write,
        .llseek = no_llseek,
-       .ioctl = snapshot_ioctl,
+       .unlocked_ioctl = snapshot_ioctl,
 };
 
 static struct miscdevice snapshot_device = {