Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

[pandora-kernel.git] / drivers / md / bitmap.c

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 53e8bea..1742435 100644 (file)
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -505,7 +505,7 @@ void bitmap_update_sb(struct bitmap *bitmap)
                return;
        }
        spin_unlock_irqrestore(&bitmap->lock, flags);
-       sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
+       sb = kmap_atomic(bitmap->sb_page, KM_USER0);
        sb->events = cpu_to_le64(bitmap->mddev->events);
        if (bitmap->mddev->events < bitmap->events_cleared) {
                /* rocking back to read-only */
@@ -526,7 +526,7 @@ void bitmap_print_sb(struct bitmap *bitmap)
 
        if (!bitmap || !bitmap->sb_page)
                return;
-       sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
+       sb = kmap_atomic(bitmap->sb_page, KM_USER0);
        printk(KERN_DEBUG "%s: bitmap file superblock:\n", bmname(bitmap));
        printk(KERN_DEBUG "         magic: %08x\n", le32_to_cpu(sb->magic));
        printk(KERN_DEBUG "       version: %d\n", le32_to_cpu(sb->version));
@@ -575,7 +575,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
                return err;
        }
 
-       sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
+       sb = kmap_atomic(bitmap->sb_page, KM_USER0);
 
        chunksize = le32_to_cpu(sb->chunksize);
        daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
@@ -661,7 +661,7 @@ static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
                return 0;
        }
        spin_unlock_irqrestore(&bitmap->lock, flags);
-       sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
+       sb = kmap_atomic(bitmap->sb_page, KM_USER0);
        old = le32_to_cpu(sb->state) & bits;
        switch (op) {
                case MASK_SET: sb->state |= cpu_to_le32(bits);
@@ -1292,9 +1292,14 @@ int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sect
        if (!bitmap) return 0;
 
        if (behind) {
+               int bw;
                atomic_inc(&bitmap->behind_writes);
+               bw = atomic_read(&bitmap->behind_writes);
+               if (bw > bitmap->behind_writes_used)
+                       bitmap->behind_writes_used = bw;
+
                PRINTK(KERN_DEBUG "inc write-behind count %d/%d\n",
-                 atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
+                      bw, bitmap->max_write_behind);
        }
 
        while (sectors) {
@@ -1351,7 +1356,8 @@ void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long secto
 {
        if (!bitmap) return;
        if (behind) {
-               atomic_dec(&bitmap->behind_writes);
+               if (atomic_dec_and_test(&bitmap->behind_writes))
+                       wake_up(&bitmap->behind_wait);
                PRINTK(KERN_DEBUG "dec write-behind count %d/%d\n",
                  atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
        }
@@ -1675,6 +1681,7 @@ int bitmap_create(mddev_t *mddev)
        atomic_set(&bitmap->pending_writes, 0);
        init_waitqueue_head(&bitmap->write_wait);
        init_waitqueue_head(&bitmap->overflow_wait);
+       init_waitqueue_head(&bitmap->behind_wait);
 
        bitmap->mddev = mddev;
 
@@ -2006,6 +2013,27 @@ static ssize_t can_clear_store(mddev_t *mddev, const char *buf, size_t len)
 static struct md_sysfs_entry bitmap_can_clear =
 __ATTR(can_clear, S_IRUGO|S_IWUSR, can_clear_show, can_clear_store);
 
+static ssize_t
+behind_writes_used_show(mddev_t *mddev, char *page)
+{
+       if (mddev->bitmap == NULL)
+               return sprintf(page, "0\n");
+       return sprintf(page, "%lu\n",
+                      mddev->bitmap->behind_writes_used);
+}
+
+static ssize_t
+behind_writes_used_reset(mddev_t *mddev, const char *buf, size_t len)
+{
+       if (mddev->bitmap)
+               mddev->bitmap->behind_writes_used = 0;
+       return len;
+}
+
+static struct md_sysfs_entry max_backlog_used =
+__ATTR(max_backlog_used, S_IRUGO | S_IWUSR,
+       behind_writes_used_show, behind_writes_used_reset);
+
 static struct attribute *md_bitmap_attrs[] = {
        &bitmap_location.attr,
        &bitmap_timeout.attr,
@@ -2013,6 +2041,7 @@ static struct attribute *md_bitmap_attrs[] = {
        &bitmap_chunksize.attr,
        &bitmap_metadata.attr,
        &bitmap_can_clear.attr,
+       &max_backlog_used.attr,
        NULL
 };
 struct attribute_group md_bitmap_group = {