[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem

This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

82 files changed, 435 insertions, 440 deletions

diff --git a/fs/affs/inode.c b/fs/affs/inode.c
index 9ebe881c678..44d439cb69f 100644
--- a/fs/affs/inode.c
+++ b/fs/affs/inode.c
@@ -244,10 +244,10 @@ affs_put_inode(struct inode *inode)
 	pr_debug("AFFS: put_inode(ino=%lu, nlink=%u)\n", inode->i_ino, inode->i_nlink);
 	affs_free_prealloc(inode);
 	if (atomic_read(&inode->i_count) == 1) {
-		down(&inode->i_sem);
+		mutex_lock(&inode->i_mutex);
 		if (inode->i_size != AFFS_I(inode)->mmu_private)
 			affs_truncate(inode);
-		up(&inode->i_sem);
+		mutex_unlock(&inode->i_mutex);
 	}
 }
 
diff --git a/fs/autofs/root.c b/fs/autofs/root.c
index a1ab1c0ed21..808134a5a2f 100644
--- a/fs/autofs/root.c
+++ b/fs/autofs/root.c
@@ -229,9 +229,9 @@ static struct dentry *autofs_root_lookup(struct inode *dir, struct dentry *dentr
 	dentry->d_flags |= DCACHE_AUTOFS_PENDING;
 	d_add(dentry, NULL);
 
-	up(&dir->i_sem);
+	mutex_unlock(&dir->i_mutex);
 	autofs_revalidate(dentry, nd);
-	down(&dir->i_sem);
+	mutex_lock(&dir->i_mutex);
 
 	/*
 	 * If we are still pending, check if we had to handle
diff --git a/fs/autofs4/root.c b/fs/autofs4/root.c
index 2241405ffc4..541b19e6fec 100644
--- a/fs/autofs4/root.c
+++ b/fs/autofs4/root.c
@@ -489,9 +489,9 @@ static struct dentry *autofs4_lookup(struct inode *dir, struct dentry *dentry, s
 	d_add(dentry, NULL);
 
 	if (dentry->d_op && dentry->d_op->d_revalidate) {
-		up(&dir->i_sem);
+		mutex_unlock(&dir->i_mutex);
 		(dentry->d_op->d_revalidate)(dentry, nd);
-		down(&dir->i_sem);
+		mutex_lock(&dir->i_mutex);
 	}
 
 	/*
diff --git a/fs/binfmt_misc.c b/fs/binfmt_misc.c
index 2568eb41cb3..9ccc7d8275b 100644
--- a/fs/binfmt_misc.c
+++ b/fs/binfmt_misc.c
@@ -588,11 +588,11 @@ static ssize_t bm_entry_write(struct file *file, const char __user *buffer,
 		case 2: set_bit(Enabled, &e->flags);
 			break;
 		case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root);
-			down(&root->d_inode->i_sem);
+			mutex_lock(&root->d_inode->i_mutex);
 
 			kill_node(e);
 
-			up(&root->d_inode->i_sem);
+			mutex_unlock(&root->d_inode->i_mutex);
 			dput(root);
 			break;
 		default: return res;
@@ -622,7 +622,7 @@ static ssize_t bm_register_write(struct file *file, const char __user *buffer,
 		return PTR_ERR(e);
 
 	root = dget(sb->s_root);
-	down(&root->d_inode->i_sem);
+	mutex_lock(&root->d_inode->i_mutex);
 	dentry = lookup_one_len(e->name, root, strlen(e->name));
 	err = PTR_ERR(dentry);
 	if (IS_ERR(dentry))
@@ -658,7 +658,7 @@ static ssize_t bm_register_write(struct file *file, const char __user *buffer,
 out2:
 	dput(dentry);
 out:
-	up(&root->d_inode->i_sem);
+	mutex_unlock(&root->d_inode->i_mutex);
 	dput(root);
 
 	if (err) {
@@ -703,12 +703,12 @@ static ssize_t bm_status_write(struct file * file, const char __user * buffer,
 		case 1: enabled = 0; break;
 		case 2: enabled = 1; break;
 		case 3: root = dget(file->f_vfsmnt->mnt_sb->s_root);
-			down(&root->d_inode->i_sem);
+			mutex_lock(&root->d_inode->i_mutex);
 
 			while (!list_empty(&entries))
 				kill_node(list_entry(entries.next, Node, list));
 
-			up(&root->d_inode->i_sem);
+			mutex_unlock(&root->d_inode->i_mutex);
 			dput(root);
 		default: return res;
 	}
diff --git a/fs/block_dev.c b/fs/block_dev.c
index e0df94c37b7..6e50346fb1e 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -202,7 +202,7 @@ static loff_t block_llseek(struct file *file, loff_t offset, int origin)
 	loff_t size;
 	loff_t retval;
 
-	down(&bd_inode->i_sem);
+	mutex_lock(&bd_inode->i_mutex);
 	size = i_size_read(bd_inode);
 
 	switch (origin) {
@@ -219,7 +219,7 @@ static loff_t block_llseek(struct file *file, loff_t offset, int origin)
 		}
 		retval = offset;
 	}
-	up(&bd_inode->i_sem);
+	mutex_unlock(&bd_inode->i_mutex);
 	return retval;
 }
 	
diff --git a/fs/buffer.c b/fs/buffer.c
index 55f0975a9b1..6466bc8a3dc 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -352,11 +352,11 @@ static long do_fsync(unsigned int fd, int datasync)
 	 * We need to protect against concurrent writers,
 	 * which could cause livelocks in fsync_buffers_list
 	 */
-	down(&mapping->host->i_sem);
+	mutex_lock(&mapping->host->i_mutex);
 	err = file->f_op->fsync(file, file->f_dentry, datasync);
 	if (!ret)
 		ret = err;
-	up(&mapping->host->i_sem);
+	mutex_unlock(&mapping->host->i_mutex);
 	err = filemap_fdatawait(mapping);
 	if (!ret)
 		ret = err;
@@ -2338,7 +2338,7 @@ int generic_commit_write(struct file *file, struct page *page,
 	__block_commit_write(inode,page,from,to);
 	/*
 	 * No need to use i_size_read() here, the i_size
-	 * cannot change under us because we hold i_sem.
+	 * cannot change under us because we hold i_mutex.
 	 */
 	if (pos > inode->i_size) {
 		i_size_write(inode, pos);
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 2a13a2bac8f..e10213b7541 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -860,9 +860,9 @@ static int cifs_oplock_thread(void * dummyarg)
 				DeleteOplockQEntry(oplock_item);
 				/* can not grab inode sem here since it would
 				deadlock when oplock received on delete 
-				since vfs_unlink holds the i_sem across
+				since vfs_unlink holds the i_mutex across
 				the call */
-				/* down(&inode->i_sem);*/
+				/* mutex_lock(&inode->i_mutex);*/
 				if (S_ISREG(inode->i_mode)) {
 					rc = filemap_fdatawrite(inode->i_mapping);
 					if(CIFS_I(inode)->clientCanCacheRead == 0) {
@@ -871,7 +871,7 @@ static int cifs_oplock_thread(void * dummyarg)
 					}
 				} else
 					rc = 0;
-				/* up(&inode->i_sem);*/
+				/* mutex_unlock(&inode->i_mutex);*/
 				if (rc)
 					CIFS_I(inode)->write_behind_rc = rc;
 				cFYI(1,("Oplock flush inode %p rc %d",inode,rc));
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 9558f51bca5..3ebce9430f4 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1040,9 +1040,9 @@ int cifs_revalidate(struct dentry *direntry)
 	}
 
 	/* can not grab this sem since kernel filesys locking documentation
-	   indicates i_sem may be taken by the kernel on lookup and rename
-	   which could deadlock if we grab the i_sem here as well */
-/*	down(&direntry->d_inode->i_sem);*/
+	   indicates i_mutex may be taken by the kernel on lookup and rename
+	   which could deadlock if we grab the i_mutex here as well */
+/*	mutex_lock(&direntry->d_inode->i_mutex);*/
 	/* need to write out dirty pages here  */
 	if (direntry->d_inode->i_mapping) {
 		/* do we need to lock inode until after invalidate completes
@@ -1066,7 +1066,7 @@ int cifs_revalidate(struct dentry *direntry)
 			}
 		}
 	}
-/*	up(&direntry->d_inode->i_sem); */
+/*	mutex_unlock(&direntry->d_inode->i_mutex); */
 	
 	kfree(full_path);
 	FreeXid(xid);
diff --git a/fs/coda/dir.c b/fs/coda/dir.c
index 2391766e9c7..8f1a517f8b4 100644
--- a/fs/coda/dir.c
+++ b/fs/coda/dir.c
@@ -453,7 +453,7 @@ int coda_readdir(struct file *coda_file, void *dirent, filldir_t filldir)
 	coda_vfs_stat.readdir++;
 
 	host_inode = host_file->f_dentry->d_inode;
-	down(&host_inode->i_sem);
+	mutex_lock(&host_inode->i_mutex);
 	host_file->f_pos = coda_file->f_pos;
 
 	if (!host_file->f_op->readdir) {
@@ -475,7 +475,7 @@ int coda_readdir(struct file *coda_file, void *dirent, filldir_t filldir)
 	}
 out:
 	coda_file->f_pos = host_file->f_pos;
-	up(&host_inode->i_sem);
+	mutex_unlock(&host_inode->i_mutex);
 
 	return ret;
 }
diff --git a/fs/coda/file.c b/fs/coda/file.c
index e6bc022568f..30b4630bd73 100644
--- a/fs/coda/file.c
+++ b/fs/coda/file.c
@@ -77,14 +77,14 @@ coda_file_write(struct file *coda_file, const char __user *buf, size_t count, lo
 		return -EINVAL;
 
 	host_inode = host_file->f_dentry->d_inode;
-	down(&coda_inode->i_sem);
+	mutex_lock(&coda_inode->i_mutex);
 
 	ret = host_file->f_op->write(host_file, buf, count, ppos);
 
 	coda_inode->i_size = host_inode->i_size;
 	coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9;
 	coda_inode->i_mtime = coda_inode->i_ctime = CURRENT_TIME_SEC;
-	up(&coda_inode->i_sem);
+	mutex_unlock(&coda_inode->i_mutex);
 
 	return ret;
 }
@@ -272,9 +272,9 @@ int coda_fsync(struct file *coda_file, struct dentry *coda_dentry, int datasync)
 	if (host_file->f_op && host_file->f_op->fsync) {
 		host_dentry = host_file->f_dentry;
 		host_inode = host_dentry->d_inode;
-		down(&host_inode->i_sem);
+		mutex_lock(&host_inode->i_mutex);
 		err = host_file->f_op->fsync(host_file, host_dentry, datasync);
-		up(&host_inode->i_sem);
+		mutex_unlock(&host_inode->i_mutex);
 	}
 
 	if ( !err && !datasync ) {
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index e48b539243a..b668ec61527 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -288,10 +288,10 @@ static struct dentry * configfs_lookup(struct inode *dir,
 
 /*
  * Only subdirectories count here.  Files (CONFIGFS_NOT_PINNED) are
- * attributes and are removed by rmdir().  We recurse, taking i_sem
+ * attributes and are removed by rmdir().  We recurse, taking i_mutex
  * on all children that are candidates for default detach.  If the
  * result is clean, then configfs_detach_group() will handle dropping
- * i_sem.  If there is an error, the caller will clean up the i_sem
+ * i_mutex.  If there is an error, the caller will clean up the i_mutex
  * holders via configfs_detach_rollback().
  */
 static int configfs_detach_prep(struct dentry *dentry)
@@ -309,8 +309,8 @@ static int configfs_detach_prep(struct dentry *dentry)
 		if (sd->s_type & CONFIGFS_NOT_PINNED)
 			continue;
 		if (sd->s_type & CONFIGFS_USET_DEFAULT) {
-			down(&sd->s_dentry->d_inode->i_sem);
-			/* Mark that we've taken i_sem */
+			mutex_lock(&sd->s_dentry->d_inode->i_mutex);
+			/* Mark that we've taken i_mutex */
 			sd->s_type |= CONFIGFS_USET_DROPPING;
 
 			ret = configfs_detach_prep(sd->s_dentry);
@@ -327,7 +327,7 @@ out:
 }
 
 /*
- * Walk the tree, dropping i_sem wherever CONFIGFS_USET_DROPPING is
+ * Walk the tree, dropping i_mutex wherever CONFIGFS_USET_DROPPING is
  * set.
  */
 static void configfs_detach_rollback(struct dentry *dentry)
@@ -341,7 +341,7 @@ static void configfs_detach_rollback(struct dentry *dentry)
 
 			if (sd->s_type & CONFIGFS_USET_DROPPING) {
 				sd->s_type &= ~CONFIGFS_USET_DROPPING;
-				up(&sd->s_dentry->d_inode->i_sem);
+				mutex_unlock(&sd->s_dentry->d_inode->i_mutex);
 			}
 		}
 	}
@@ -424,11 +424,11 @@ static void detach_groups(struct config_group *group)
 
 		/*
 		 * From rmdir/unregister, a configfs_detach_prep() pass
-		 * has taken our i_sem for us.  Drop it.
+		 * has taken our i_mutex for us.  Drop it.
 		 * From mkdir/register cleanup, there is no sem held.
 		 */
 		if (sd->s_type & CONFIGFS_USET_DROPPING)
-			up(&child->d_inode->i_sem);
+			mutex_unlock(&child->d_inode->i_mutex);
 
 		d_delete(child);
 		dput(child);
@@ -493,11 +493,11 @@ static int populate_groups(struct config_group *group)
 		/* FYI, we're faking mkdir here
 		 * I'm not sure we need this semaphore, as we're called
 		 * from our parent's mkdir.  That holds our parent's
-		 * i_sem, so afaik lookup cannot continue through our
+		 * i_mutex, so afaik lookup cannot continue through our
 		 * parent to find us, let alone mess with our tree.
-		 * That said, taking our i_sem is closer to mkdir
+		 * That said, taking our i_mutex is closer to mkdir
 		 * emulation, and shouldn't hurt. */
-		down(&dentry->d_inode->i_sem);
+		mutex_lock(&dentry->d_inode->i_mutex);
 
 		for (i = 0; group->default_groups[i]; i++) {
 			new_group = group->default_groups[i];
@@ -507,7 +507,7 @@ static int populate_groups(struct config_group *group)
 				break;
 		}
 
-		up(&dentry->d_inode->i_sem);
+		mutex_unlock(&dentry->d_inode->i_mutex);
 	}
 
 	if (ret)
@@ -856,7 +856,7 @@ int configfs_rename_dir(struct config_item * item, const char *new_name)
 	down_write(&configfs_rename_sem);
 	parent = item->parent->dentry;
 
-	down(&parent->d_inode->i_sem);
+	mutex_lock(&parent->d_inode->i_mutex);
 
 	new_dentry = lookup_one_len(new_name, parent, strlen(new_name));
 	if (!IS_ERR(new_dentry)) {
@@ -872,7 +872,7 @@ int configfs_rename_dir(struct config_item * item, const char *new_name)
 			error = -EEXIST;
 		dput(new_dentry);
 	}
-	up(&parent->d_inode->i_sem);
+	mutex_unlock(&parent->d_inode->i_mutex);
 	up_write(&configfs_rename_sem);
 
 	return error;
@@ -884,9 +884,9 @@ static int configfs_dir_open(struct inode *inode, struct file *file)
 	struct dentry * dentry = file->f_dentry;
 	struct configfs_dirent * parent_sd = dentry->d_fsdata;
 
-	down(&dentry->d_inode->i_sem);
+	mutex_lock(&dentry->d_inode->i_mutex);
 	file->private_data = configfs_new_dirent(parent_sd, NULL);
-	up(&dentry->d_inode->i_sem);
+	mutex_unlock(&dentry->d_inode->i_mutex);
 
 	return file->private_data ? 0 : -ENOMEM;
 
@@ -897,9 +897,9 @@ static int configfs_dir_close(struct inode *inode, struct file *file)
 	struct dentry * dentry = file->f_dentry;
 	struct configfs_dirent * cursor = file->private_data;
 
-	down(&dentry->d_inode->i_sem);
+	mutex_lock(&dentry->d_inode->i_mutex);
 	list_del_init(&cursor->s_sibling);
-	up(&dentry->d_inode->i_sem);
+	mutex_unlock(&dentry->d_inode->i_mutex);
 
 	release_configfs_dirent(cursor);
 
@@ -975,7 +975,7 @@ static loff_t configfs_dir_lseek(struct file * file, loff_t offset, int origin)
 {
 	struct dentry * dentry = file->f_dentry;
 
-	down(&dentry->d_inode->i_sem);
+	mutex_lock(&dentry->d_inode->i_mutex);
 	switch (origin) {
 		case 1:
 			offset += file->f_pos;
@@ -983,7 +983,7 @@ static loff_t configfs_dir_lseek(struct file * file, loff_t offset, int origin)
 			if (offset >= 0)
 				break;
 		default:
-			up(&file->f_dentry->d_inode->i_sem);
+			mutex_unlock(&file->f_dentry->d_inode->i_mutex);
 			return -EINVAL;
 	}
 	if (offset != file->f_pos) {
@@ -1007,7 +1007,7 @@ static loff_t configfs_dir_lseek(struct file * file, loff_t offset, int origin)
 			list_add_tail(&cursor->s_sibling, p);
 		}
 	}
-	up(&dentry->d_inode->i_sem);
+	mutex_unlock(&dentry->d_inode->i_mutex);
 	return offset;
 }
 
@@ -1037,7 +1037,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 	sd = configfs_sb->s_root->d_fsdata;
 	link_group(to_config_group(sd->s_element), group);
 
-	down(&configfs_sb->s_root->d_inode->i_sem);
+	mutex_lock(&configfs_sb->s_root->d_inode->i_mutex);
 
 	name.name = group->cg_item.ci_name;
 	name.len = strlen(name.name);
@@ -1057,7 +1057,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 	else
 		d_delete(dentry);
 
-	up(&configfs_sb->s_root->d_inode->i_sem);
+	mutex_unlock(&configfs_sb->s_root->d_inode->i_mutex);
 
 	if (dentry) {
 	    dput(dentry);
@@ -1079,18 +1079,18 @@ void configfs_unregister_subsystem(s