1 files changed, 158 insertions, 14 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index fa608a1a5c20..c402f6cc7047 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -19,6 +19,9 @@
 
      Neil Brown <neilb@cse.unsw.edu.au>.
 
+   - persistent bitmap code
+     Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
+
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2, or (at your option)
@@ -33,6 +36,7 @@
 #include <linux/config.h>
 #include <linux/linkage.h>
 #include <linux/raid/md.h>
+#include <linux/raid/bitmap.h>
 #include <linux/sysctl.h>
 #include <linux/devfs_fs_kernel.h>
 #include <linux/buffer_head.h> /* for invalidate_bdev */
@@ -40,6 +44,8 @@
 
 #include <linux/init.h>
 
+#include <linux/file.h>
+
 #ifdef CONFIG_KMOD
 #include <linux/kmod.h>
 #endif
@@ -1198,8 +1204,11 @@ void md_print_devices(void)
         printk("md:     * <COMPLETE RAID STATE PRINTOUT> *\n");
         printk("md:     **********************************\n");
         ITERATE_MDDEV(mddev,tmp) {
-                printk("%s: ", mdname(mddev));
 
+                if (mddev->bitmap)
+                        bitmap_print_sb(mddev->bitmap);
+                else
+                        printk("%s: ", mdname(mddev));
                 ITERATE_RDEV(mddev,rdev,tmp2)
                         printk("<%s>", bdevname(rdev->bdev,b));
                 printk("\n");
@@ -1287,7 +1296,7 @@ repeat:
                 "md: updating %s RAID superblock on device (in sync %d)\n",
                 mdname(mddev),mddev->in_sync);
 
-        err = 0;
+        err = bitmap_update_sb(mddev->bitmap);
         ITERATE_RDEV(mddev,rdev,tmp) {
                 char b[BDEVNAME_SIZE];
                 dprintk(KERN_INFO "md: ");
@@ -1624,12 +1633,19 @@ static int do_md_run(mddev_t * mddev)
 
         mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */
 
-        err = mddev->pers->run(mddev);
+        /* before we start the array running, initialise the bitmap */
+        err = bitmap_create(mddev);
+        if (err)
+                printk(KERN_ERR "%s: failed to create bitmap (%d)\n",
+                        mdname(mddev), err);
+        else
+                err = mddev->pers->run(mddev);
         if (err) {
                 printk(KERN_ERR "md: pers->run() failed ...\n");
                 module_put(mddev->pers->owner);
                 mddev->pers = NULL;
-                return -EINVAL;
+                bitmap_destroy(mddev);
+                return err;
         }
         atomic_set(&mddev->writes_pending,0);
         mddev->safemode = 0;
@@ -1742,6 +1758,14 @@ static int do_md_stop(mddev_t * mddev, int ro)
                 if (ro)
                         set_disk_ro(disk, 1);
         }
+
+        bitmap_destroy(mddev);
+        if (mddev->bitmap_file) {
+                atomic_set(&mddev->bitmap_file->f_dentry->d_inode->i_writecount, 1);
+                fput(mddev->bitmap_file);
+                mddev->bitmap_file = NULL;
+        }
+
         /*
          * Free resources if final stop
          */
@@ -2000,6 +2024,42 @@ static int get_array_info(mddev_t * mddev, void __user * arg)
         return 0;
 }
 
+static int get_bitmap_file(mddev_t * mddev, void * arg)
+{
+        mdu_bitmap_file_t *file = NULL; /* too big for stack allocation */
+        char *ptr, *buf = NULL;
+        int err = -ENOMEM;
+
+        file = kmalloc(sizeof(*file), GFP_KERNEL);
+        if (!file)
+                goto out;
+
+        /* bitmap disabled, zero the first byte and copy out */
+        if (!mddev->bitmap || !mddev->bitmap->file) {
+                file->pathname[0] = '\0';
+                goto copy_out;
+        }
+
+        buf = kmalloc(sizeof(file->pathname), GFP_KERNEL);
+        if (!buf)
+                goto out;
+
+        ptr = file_path(mddev->bitmap->file, buf, sizeof(file->pathname));
+        if (!ptr)
+                goto out;
+
+        strcpy(file->pathname, ptr);
+
+copy_out:
+        err = 0;
+        if (copy_to_user(arg, file, sizeof(*file)))
+                err = -EFAULT;
+out:
+        kfree(buf);
+        kfree(file);
+        return err;
+}
+
 static int get_disk_info(mddev_t * mddev, void __user * arg)
 {
         mdu_disk_info_t info;
@@ -2275,6 +2335,48 @@ abort_export:
         return err;
 }
 
+/* similar to deny_write_access, but accounts for our holding a reference
+ * to the file ourselves */
+static int deny_bitmap_write_access(struct file * file)
+{
+        struct inode *inode = file->f_mapping->host;
+
+        spin_lock(&inode->i_lock);
+        if (atomic_read(&inode->i_writecount) > 1) {
+                spin_unlock(&inode->i_lock);
+                return -ETXTBSY;
+        }
+        atomic_set(&inode->i_writecount, -1);
+        spin_unlock(&inode->i_lock);
+
+        return 0;
+}
+
+static int set_bitmap_file(mddev_t *mddev, int fd)
+{
+        int err;
+
+        if (mddev->pers)
+                return -EBUSY;
+
+        mddev->bitmap_file = fget(fd);
+
+        if (mddev->bitmap_file == NULL) {
+                printk(KERN_ERR "%s: error: failed to get bitmap file\n",
+                        mdname(mddev));
+                return -EBADF;
+        }
+
+        err = deny_bitmap_write_access(mddev->bitmap_file);
+        if (err) {
+                printk(KERN_ERR "%s: error: bitmap file is already in use\n",
+                        mdname(mddev));
+                fput(mddev->bitmap_file);
+                mddev->bitmap_file = NULL;
+        }
+        return err;
+}
+
 /*
  * set_array_info is used two different ways
  * The original usage is when creating a new array.
@@ -2586,8 +2688,10 @@ static int md_ioctl(struct inode *inode, struct file *file,
         /*
          * Commands querying/configuring an existing array:
          */
-        /* if we are initialised yet, only ADD_NEW_DISK or STOP_ARRAY is allowed */
-        if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY && cmd != RUN_ARRAY) {
+        /* if we are not initialised yet, only ADD_NEW_DISK, STOP_ARRAY,
+         * RUN_ARRAY, and SET_BITMAP_FILE are allowed */
+        if (!mddev->raid_disks && cmd != ADD_NEW_DISK && cmd != STOP_ARRAY
+                        && cmd != RUN_ARRAY && cmd != SET_BITMAP_FILE) {
                 err = -ENODEV;
                 goto abort_unlock;
         }
@@ -2601,6 +2705,10 @@ static int md_ioctl(struct inode *inode, struct file *file,
                         err = get_array_info(mddev, argp);
                         goto done_unlock;
 
+                case GET_BITMAP_FILE:
+                        err = get_bitmap_file(mddev, (void *)arg);
+                        goto done_unlock;
+
                 case GET_DISK_INFO:
                         err = get_disk_info(mddev, argp);
                         goto done_unlock;
@@ -2681,6 +2789,10 @@ static int md_ioctl(struct inode *inode, struct file *file,
                         err = do_md_run (mddev);
                         goto done_unlock;
 
+                case SET_BITMAP_FILE:
+                        err = set_bitmap_file(mddev, (int)arg);
+                        goto done_unlock;
+
                 default:
                         if (_IOC_TYPE(cmd) == MD_MAJOR)
                                 printk(KERN_WARNING "md: %s(pid %d) used"
@@ -2792,8 +2904,9 @@ static int md_thread(void * arg)
         while (thread->run) {
                 void (*run)(mddev_t *);
 
-                wait_event_interruptible(thread->wqueue,
-                                         test_bit(THREAD_WAKEUP, &thread->flags));
+                wait_event_interruptible_timeout(thread->wqueue,
+                                                 test_bit(THREAD_WAKEUP, &thread->flags),
+                                                 thread->timeout);
                 if (current->flags & PF_FREEZE)
                         refrigerator(PF_FREEZE);
 
@@ -2839,6 +2952,7 @@ mdk_thread_t *md_register_thread(void (*run) (mddev_t *), mddev_t *mddev,
         thread->run = run;
         thread->mddev = mddev;
         thread->name = name;
+        thread->timeout = MAX_SCHEDULE_TIMEOUT;
         ret = kernel_thread(md_thread, thread, 0);
         if (ret < 0) {
                 kfree(thread);
@@ -2877,13 +2991,13 @@ void md_error(mddev_t *mddev, mdk_rdev_t *rdev)
 
         if (!rdev || rdev->faulty)
                 return;
-
+/*
         dprintk("md_error dev:%s, rdev:(%d:%d), (caller: %p,%p,%p,%p).\n",
                 mdname(mddev),
                 MAJOR(rdev->bdev->bd_dev), MINOR(rdev->bdev->bd_dev),
                 __builtin_return_address(0),__builtin_return_address(1),
                 __builtin_return_address(2),__builtin_return_address(3));
-
+*/
         if (!mddev->pers->error_handler)
                 return;
         mddev->pers->error_handler(mddev,rdev);
@@ -3037,6 +3151,7 @@ static int md_seq_show(struct seq_file *seq, void *v)
         struct list_head *tmp2;
         mdk_rdev_t *rdev;
         int i;
+        struct bitmap *bitmap;
 
         if (v == (void*)1) {
                 seq_printf(seq, "Personalities : ");
@@ -3089,10 +3204,36 @@ static int md_seq_show(struct seq_file *seq, void *v)
                 if (mddev->pers) {
                         mddev->pers->status (seq, mddev);
                         seq_printf(seq, "\n      ");
-                        if (mddev->curr_resync > 2)
+                        if (mddev->curr_resync > 2) {
                                 status_resync (seq, mddev);
-                        else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
-                                seq_printf(seq, "       resync=DELAYED");
+                                seq_printf(seq, "\n      ");
+                        } else if (mddev->curr_resync == 1 || mddev->curr_resync == 2)
+                                seq_printf(seq, "       resync=DELAYED\n      ");
+                } else
+                        seq_printf(seq, "\n       ");
+
+                if ((bitmap = mddev->bitmap)) {
+                        char *buf, *path;
+                        unsigned long chunk_kb;
+                        unsigned long flags;
+                        buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+                        spin_lock_irqsave(&bitmap->lock, flags);
+                        chunk_kb = bitmap->chunksize >> 10;
+                        seq_printf(seq, "bitmap: %lu/%lu pages [%luKB], "
+                                "%lu%s chunk",
+                                bitmap->pages - bitmap->missing_pages,
+                                bitmap->pages,
+                                (bitmap->pages - bitmap->missing_pages)
+                                        << (PAGE_SHIFT - 10),
+                                chunk_kb ? chunk_kb : bitmap->chunksize,
+                                chunk_kb ? "KB" : "B");
+                        if (bitmap->file && buf) {
+                                path = file_path(bitmap->file, buf, PAGE_SIZE);
+                                seq_printf(seq, ", file: %s", path ? path : "");
+                        }
+                        seq_printf(seq, "\n");
+                        spin_unlock_irqrestore(&bitmap->lock, flags);
+                        kfree(buf);
                 }
 
                 seq_printf(seq, "\n");
@@ -3328,7 +3469,8 @@ static void md_do_sync(mddev_t *mddev)
                sysctl_speed_limit_max);
 
         is_mddev_idle(mddev); /* this also initializes IO event counters */
-        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery))
+        /* we don't use the checkpoint if there's a bitmap */
+        if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !mddev->bitmap)
                 j = mddev->recovery_cp;
         else
                 j = 0;
@@ -3673,6 +3815,8 @@ static int __init md_init(void)
                         " MD_SB_DISKS=%d\n",
                         MD_MAJOR_VERSION, MD_MINOR_VERSION,
                         MD_PATCHLEVEL_VERSION, MAX_MD_DEVS, MD_SB_DISKS);
+        printk(KERN_INFO "md: bitmap version %d.%d\n", BITMAP_MAJOR,
+                        BITMAP_MINOR);
 
         if (register_blkdev(MAJOR_NR, "md"))
                 return -1;