1 files changed, 77 insertions, 121 deletions

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 91013ff7dd53..c54226be5294 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -64,6 +64,28 @@ static void writeback_release(struct backing_dev_info *bdi)
         clear_bit(BDI_pdflush, &bdi->state);
 }
 
+static noinline void block_dump___mark_inode_dirty(struct inode *inode)
+{
+        if (inode->i_ino || strcmp(inode->i_sb->s_id, "bdev")) {
+                struct dentry *dentry;
+                const char *name = "?";
+
+                dentry = d_find_alias(inode);
+                if (dentry) {
+                        spin_lock(&dentry->d_lock);
+                        name = (const char *) dentry->d_name.name;
+                }
+                printk(KERN_DEBUG
+                       "%s(%d): dirtied inode %lu (%s) on %s\n",
+                       current->comm, task_pid_nr(current), inode->i_ino,
+                       name, inode->i_sb->s_id);
+                if (dentry) {
+                        spin_unlock(&dentry->d_lock);
+                        dput(dentry);
+                }
+        }
+}
+
 /**
  *      __mark_inode_dirty -    internal function
  *      @inode: inode to mark
@@ -114,23 +136,8 @@ void __mark_inode_dirty(struct inode *inode, int flags)
         if ((inode->i_state & flags) == flags)
                 return;
 
-        if (unlikely(block_dump)) {
-                struct dentry *dentry = NULL;
-                const char *name = "?";
-
-                if (!list_empty(&inode->i_dentry)) {
-                        dentry = list_entry(inode->i_dentry.next,
-                                            struct dentry, d_alias);
-                        if (dentry && dentry->d_name.name)
-                                name = (const char *) dentry->d_name.name;
-                }
-
-                if (inode->i_ino || strcmp(inode->i_sb->s_id, "bdev"))
-                        printk(KERN_DEBUG
-                               "%s(%d): dirtied inode %lu (%s) on %s\n",
-                               current->comm, task_pid_nr(current), inode->i_ino,
-                               name, inode->i_sb->s_id);
-        }
+        if (unlikely(block_dump))
+                block_dump___mark_inode_dirty(inode);
 
         spin_lock(&inode_lock);
         if ((inode->i_state & flags) != flags) {
@@ -271,7 +278,26 @@ int sb_has_dirty_inodes(struct super_block *sb)
 EXPORT_SYMBOL(sb_has_dirty_inodes);
 
 /*
- * Write a single inode's dirty pages and inode data out to disk.
+ * Wait for writeback on an inode to complete.
+ */
+static void inode_wait_for_writeback(struct inode *inode)
+{
+        DEFINE_WAIT_BIT(wq, &inode->i_state, __I_SYNC);
+        wait_queue_head_t *wqh;
+
+        wqh = bit_waitqueue(&inode->i_state, __I_SYNC);
+        do {
+                spin_unlock(&inode_lock);
+                __wait_on_bit(wqh, &wq, inode_wait, TASK_UNINTERRUPTIBLE);
+                spin_lock(&inode_lock);
+        } while (inode->i_state & I_SYNC);
+}
+
+/*
+ * Write out an inode's dirty pages.  Called under inode_lock.  Either the
+ * caller has ref on the inode (either via __iget or via syscall against an fd)
+ * or the inode has I_WILL_FREE set (via generic_forget_inode)
+ *
  * If `wait' is set, wait on the writeout.
  *
  * The whole writeout design is quite complex and fragile.  We want to avoid
@@ -281,15 +307,39 @@ EXPORT_SYMBOL(sb_has_dirty_inodes);
  * Called under inode_lock.
  */
 static int
-__sync_single_inode(struct inode *inode, struct writeback_control *wbc)
+writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 {
-        unsigned dirty;
         struct address_space *mapping = inode->i_mapping;
         int wait = wbc->sync_mode == WB_SYNC_ALL;
+        unsigned dirty;
         int ret;
 
+        if (!atomic_read(&inode->i_count))
+                WARN_ON(!(inode->i_state & (I_WILL_FREE|I_FREEING)));
+        else
+                WARN_ON(inode->i_state & I_WILL_FREE);
+
+        if (inode->i_state & I_SYNC) {
+                /*
+                 * If this inode is locked for writeback and we are not doing
+                 * writeback-for-data-integrity, move it to s_more_io so that
+                 * writeback can proceed with the other inodes on s_io.
+                 *
+                 * We'll have another go at writing back this inode when we
+                 * completed a full scan of s_io.
+                 */
+                if (!wait) {
+                        requeue_io(inode);
+                        return 0;
+                }
+
+                /*
+                 * It's a data-integrity sync.  We must wait.
+                 */
+                inode_wait_for_writeback(inode);
+        }
+
         BUG_ON(inode->i_state & I_SYNC);
-        WARN_ON(inode->i_state & I_NEW);
 
         /* Set I_SYNC, reset I_DIRTY */
         dirty = inode->i_state & I_DIRTY;
@@ -314,9 +364,8 @@ __sync_single_inode(struct inode *inode, struct writeback_control *wbc)
         }
 
         spin_lock(&inode_lock);
-        WARN_ON(inode->i_state & I_NEW);
         inode->i_state &= ~I_SYNC;
-        if (!(inode->i_state & I_FREEING)) {
+        if (!(inode->i_state & (I_FREEING | I_CLEAR))) {
                 if (!(inode->i_state & I_DIRTY) &&
                     mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
                         /*
@@ -385,50 +434,6 @@ __sync_single_inode(struct inode *inode, struct writeback_control *wbc)
 }
 
 /*
- * Write out an inode's dirty pages.  Called under inode_lock.  Either the
- * caller has ref on the inode (either via __iget or via syscall against an fd)
- * or the inode has I_WILL_FREE set (via generic_forget_inode)
- */
-static int
-__writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
-{
-        wait_queue_head_t *wqh;
-
-        if (!atomic_read(&inode->i_count))
-                WARN_ON(!(inode->i_state & (I_WILL_FREE|I_FREEING)));
-        else
-                WARN_ON(inode->i_state & I_WILL_FREE);
-
-        if ((wbc->sync_mode != WB_SYNC_ALL) && (inode->i_state & I_SYNC)) {
-                /*
-                 * We're skipping this inode because it's locked, and we're not
-                 * doing writeback-for-data-integrity.  Move it to s_more_io so
-                 * that writeback can proceed with the other inodes on s_io.
-                 * We'll have another go at writing back this inode when we
-                 * completed a full scan of s_io.
-                 */
-                requeue_io(inode);
-                return 0;
-        }
-
-        /*
-         * It's a data-integrity sync.  We must wait.
-         */
-        if (inode->i_state & I_SYNC) {
-                DEFINE_WAIT_BIT(wq, &inode->i_state, __I_SYNC);
-
-                wqh = bit_waitqueue(&inode->i_state, __I_SYNC);
-                do {
-                        spin_unlock(&inode_lock);
-                        __wait_on_bit(wqh, &wq, inode_wait,
-                                                        TASK_UNINTERRUPTIBLE);
-                        spin_lock(&inode_lock);
-                } while (inode->i_state & I_SYNC);
-        }
-        return __sync_single_inode(inode, wbc);
-}
-
-/*
  * Write out a superblock's list of dirty inodes.  A wait will be performed
  * upon no inodes, all inodes or the final one, depending upon sync_mode.
  *
@@ -487,7 +492,7 @@ void generic_sync_sb_inodes(struct super_block *sb,
                         break;
                 }
 
-                if (inode->i_state & I_NEW) {
+                if (inode->i_state & (I_NEW | I_WILL_FREE)) {
                         requeue_io(inode);
                         continue;
                 }
@@ -518,10 +523,10 @@ void generic_sync_sb_inodes(struct super_block *sb,
                 if (current_is_pdflush() && !writeback_acquire(bdi))
                         break;
 
-                BUG_ON(inode->i_state & I_FREEING);
+                BUG_ON(inode->i_state & (I_FREEING | I_CLEAR));
                 __iget(inode);
                 pages_skipped = wbc->pages_skipped;
-                __writeback_single_inode(inode, wbc);
+                writeback_single_inode(inode, wbc);
                 if (current_is_pdflush())
                         writeback_release(bdi);
                 if (wbc->pages_skipped != pages_skipped) {
@@ -679,55 +684,6 @@ void sync_inodes_sb(struct super_block *sb, int wait)
 }
 
 /**
- * sync_inodes - writes all inodes to disk
- * @wait: wait for completion
- *
- * sync_inodes() goes through each super block's dirty inode list, writes the
- * inodes out, waits on the writeout and puts the inodes back on the normal
- * list.
- *
- * This is for sys_sync().  fsync_dev() uses the same algorithm.  The subtle
- * part of the sync functions is that the blockdev "superblock" is processed
- * last.  This is because the write_inode() function of a typical fs will
- * perform no I/O, but will mark buffers in the blockdev mapping as dirty.
- * What we want to do is to perform all that dirtying first, and then write
- * back all those inode blocks via the blockdev mapping in one sweep.  So the
- * additional (somewhat redundant) sync_blockdev() calls here are to make
- * sure that really happens.  Because if we call sync_inodes_sb(wait=1) with
- * outstanding dirty inodes, the writeback goes block-at-a-time within the
- * filesystem's write_inode().  This is extremely slow.
- */
-static void __sync_inodes(int wait)
-{
-        struct super_block *sb;
-
-        spin_lock(&sb_lock);
-restart:
-        list_for_each_entry(sb, &super_blocks, s_list) {
-                sb->s_count++;
-                spin_unlock(&sb_lock);
-                down_read(&sb->s_umount);
-                if (sb->s_root) {
-                        sync_inodes_sb(sb, wait);
-                        sync_blockdev(sb->s_bdev);
-                }
-                up_read(&sb->s_umount);
-                spin_lock(&sb_lock);
-                if (__put_super_and_need_restart(sb))
-                        goto restart;
-        }
-        spin_unlock(&sb_lock);
-}
-
-void sync_inodes(int wait)
-{
-        __sync_inodes(0);
-
-        if (wait)
-                __sync_inodes(1);
-}
-
-/**
  * write_inode_now      -       write an inode to disk
  * @inode: inode to write to disk
  * @sync: whether the write should be synchronous or not
@@ -752,7 +708,7 @@ int write_inode_now(struct inode *inode, int sync)
 
         might_sleep();
         spin_lock(&inode_lock);
-        ret = __writeback_single_inode(inode, &wbc);
+        ret = writeback_single_inode(inode, &wbc);
         spin_unlock(&inode_lock);
         if (sync)
                 inode_sync_wait(inode);
@@ -776,7 +732,7 @@ int sync_inode(struct inode *inode, struct writeback_control *wbc)
         int ret;
 
         spin_lock(&inode_lock);
-        ret = __writeback_single_inode(inode, wbc);
+        ret = writeback_single_inode(inode, wbc);
         spin_unlock(&inode_lock);
         return ret;
 }