fs-Convert-i_alloc_sem-to-rw_anon_semaphore.patch

From dd850b2ccb230ada53e5bb63664e0fd53284af38 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 26 Jul 2009 17:38:49 +0200
Subject: [PATCH] fs: Convert i_alloc_sem to rw_anon_semaphore

commit 087498eea02acae08627e310d58ec837a54752d7 in tip.

i_alloc_sem is used as a completion in direct-io which does not follow
owner rules. preempt-rt needs to keep it as such. So convert it to
rw_anon_semaphore and annotate the semantics hereby.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/fs/attr.c b/fs/attr.c
index 96d394b..b3f0527 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -206,7 +206,7 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
 		return error;
 
 	if (ia_valid & ATTR_SIZE)
-		down_write(&dentry->d_inode->i_alloc_sem);
+		anon_down_write(&dentry->d_inode->i_alloc_sem);
 
 	if (inode->i_op && inode->i_op->setattr) {
 		error = inode->i_op->setattr(dentry, attr);
@@ -223,7 +223,7 @@ int notify_change(struct dentry * dentry, struct iattr * attr)
 	}
 
 	if (ia_valid & ATTR_SIZE)
-		up_write(&dentry->d_inode->i_alloc_sem);
+		anon_up_write(&dentry->d_inode->i_alloc_sem);
 
 	if (!error)
 		fsnotify_change(dentry, ia_valid);
diff --git a/fs/direct-io.c b/fs/direct-io.c
index e82adc2..45ee3f6 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -242,7 +242,7 @@ static int dio_complete(struct dio *dio, loff_t offset, int ret)
 
 	if (dio->flags & DIO_LOCKING)
 		/* lockdep: non-owner release */
-		up_read_non_owner(&dio->inode->i_alloc_sem);
+		anon_up_read_non_owner(&dio->inode->i_alloc_sem);
 
 	if (ret == 0)
 		ret = dio->page_errors;
@@ -1184,7 +1184,7 @@ __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
 		 * Will be released at I/O completion, possibly in a
 		 * different thread.
 		 */
-		down_read_non_owner(&inode->i_alloc_sem);
+		anon_down_read_non_owner(&inode->i_alloc_sem);
 	}
 
 	/*
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index e119524..89dbb38 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5768,7 +5768,7 @@ int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 	 * Get i_alloc_sem to stop truncates messing with the inode. We cannot
 	 * get i_mutex because we are already holding mmap_sem.
 	 */
-	down_read(&inode->i_alloc_sem);
+	anon_down_read(&inode->i_alloc_sem);
 	size = i_size_read(inode);
 	if (page->mapping != mapping || size <= page_offset(page)
 	    || !PageUptodate(page)) {
@@ -5818,6 +5818,6 @@ int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 out_unlock:
 	if (ret)
 		ret = VM_FAULT_SIGBUS;
-	up_read(&inode->i_alloc_sem);
+	anon_up_read(&inode->i_alloc_sem);
 	return ret;
 }
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 14da530..5c5e1cd 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -202,9 +202,9 @@ static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
 	sector_t blocknr;
 
 	/* fat_get_cluster() assumes the requested blocknr isn't truncated. */
-	down_read(&mapping->host->i_alloc_sem);
+	anon_down_read(&mapping->host->i_alloc_sem);
 	blocknr = generic_block_bmap(mapping, block, fat_get_block);
-	up_read(&mapping->host->i_alloc_sem);
+	anon_up_read(&mapping->host->i_alloc_sem);
 
 	return blocknr;
 }
diff --git a/fs/inode.c b/fs/inode.c
index 03dfeb2..ce10948 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -162,7 +162,7 @@ int inode_init_always(struct super_block *sb, struct inode *inode)
 	mutex_init(&inode->i_mutex);
 	lockdep_set_class(&inode->i_mutex, &sb->s_type->i_mutex_key);
 
-	init_rwsem(&inode->i_alloc_sem);
+	init_anon_rwsem(&inode->i_alloc_sem);
 	lockdep_set_class(&inode->i_alloc_sem, &sb->s_type->i_alloc_sem_key);
 
 	mapping->a_ops = &empty_aops;
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 06713ff..e7ed4cd 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -509,7 +509,7 @@ nilfs_mdt_new_common(struct the_nilfs *nilfs, struct super_block *sb,
 
 		spin_lock_init(&inode->i_lock);
 		mutex_init(&inode->i_mutex);
-		init_rwsem(&inode->i_alloc_sem);
+		init_anon_rwsem(&inode->i_alloc_sem);
 
 		mapping->host = NULL;  /* instead of inode */
 		mapping->flags = 0;
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index 43179dd..b3d9d74 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -1845,9 +1845,9 @@ static ssize_t ntfs_file_buffered_write(struct kiocb *iocb,
 	 * fails again.
 	 */
 	if (unlikely(NInoTruncateFailed(ni))) {
-		down_write(&vi->i_alloc_sem);
+		anon_down_write(&vi->i_alloc_sem);
 		err = ntfs_truncate(vi);
-		up_write(&vi->i_alloc_sem);
+		anon_up_write(&vi->i_alloc_sem);
 		if (err || NInoTruncateFailed(ni)) {
 			if (!err)
 				err = -EIO;
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 7e9df11..5d55344 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -620,7 +620,7 @@ static void ocfs2_dio_end_io(struct kiocb *iocb,
 
 	level = ocfs2_iocb_rw_locked_level(iocb);
 	if (!level)
-		up_read(&inode->i_alloc_sem);
+		anon_up_read(&inode->i_alloc_sem);
 	ocfs2_rw_unlock(inode, level);
 }
 
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 558ce03..4394eec 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1934,7 +1934,7 @@ static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
 relock:
 	/* to match setattr's i_mutex -> i_alloc_sem -> rw_lock ordering */
 	if (direct_io) {
-		down_read(&inode->i_alloc_sem);
+		anon_down_read(&inode->i_alloc_sem);
 		have_alloc_sem = 1;
 	}
 
@@ -1961,7 +1961,7 @@ relock:
 	 */
 	if (direct_io && !can_do_direct) {
 		ocfs2_rw_unlock(inode, rw_level);
-		up_read(&inode->i_alloc_sem);
+		anon_up_read(&inode->i_alloc_sem);
 
 		have_alloc_sem = 0;
 		rw_level = -1;
@@ -2054,7 +2054,7 @@ out:
 
 out_sems:
 	if (have_alloc_sem)
-		up_read(&inode->i_alloc_sem);
+		anon_up_read(&inode->i_alloc_sem);
 
 	mutex_unlock(&inode->i_mutex);
 
@@ -2203,7 +2203,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
 	 * need locks to protect pending reads from racing with truncate.
 	 */
 	if (filp->f_flags & O_DIRECT) {
-		down_read(&inode->i_alloc_sem);
+		anon_down_read(&inode->i_alloc_sem);
 		have_alloc_sem = 1;
 
 		ret = ocfs2_rw_lock(inode, 0);
@@ -2247,7 +2247,7 @@ static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
 
 bail:
 	if (have_alloc_sem)
-		up_read(&inode->i_alloc_sem);
+		anon_up_read(&inode->i_alloc_sem);
 	if (rw_level != -1)
 		ocfs2_rw_unlock(inode, rw_level);
 	mlog_exit(ret);
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index 81f09fa..75f4c0b 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -563,11 +563,11 @@ reiserfs_xattr_set_handle(struct reiserfs_transaction_handle *th,
 
 		reiserfs_write_unlock(inode->i_sb);
 		mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_XATTR);
-		down_write(&dentry->d_inode->i_alloc_sem);
+		anon_down_write(&dentry->d_inode->i_alloc_sem);
 		reiserfs_write_lock(inode->i_sb);
 
 		err = reiserfs_setattr(dentry, &newattrs);
-		up_write(&dentry->d_inode->i_alloc_sem);
+		anon_up_write(&dentry->d_inode->i_alloc_sem);
 		mutex_unlock(&dentry->d_inode->i_mutex);
 	} else
 		update_ctime(inode);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ebb1cd5..590c104 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -743,7 +743,7 @@ struct inode {
 	umode_t			i_mode;
 	spinlock_t		i_lock;	/* i_blocks, i_bytes, maybe i_size */
 	struct mutex		i_mutex;
-	struct rw_semaphore	i_alloc_sem;
+	struct rw_anon_semaphore	i_alloc_sem;
 	const struct inode_operations	*i_op;
 	const struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
 	struct super_block	*i_sb;
diff --git a/mm/memory.c b/mm/memory.c
index fef5225..553bf3d 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2494,12 +2494,12 @@ int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
 		return -ENOSYS;
 
 	mutex_lock(&inode->i_mutex);
-	down_write(&inode->i_alloc_sem);
+	anon_down_write(&inode->i_alloc_sem);
 	unmap_mapping_range(mapping, offset, (end - offset), 1);
 	truncate_inode_pages_range(mapping, offset, end);
 	unmap_mapping_range(mapping, offset, (end - offset), 1);
 	inode->i_op->truncate_range(inode, offset, end);
-	up_write(&inode->i_alloc_sem);
+	anon_up_write(&inode->i_alloc_sem);
 	mutex_unlock(&inode->i_mutex);
 
 	return 0;
-- 
1.7.1.1