[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>

arch/powerpc/platforms/cell/spufs/inode.c

@@ -137,7 +137,7 @@ spufs_delete_inode(struct inode *inode)
 static void spufs_prune_dir(struct dentry *dir)
 {
 	struct dentry *dentry, *tmp;
-	down(&dir->d_inode->i_sem);
+	mutex_lock(&dir->d_inode->i_mutex);
 	list_for_each_entry_safe(dentry, tmp, &dir->d_subdirs, d_child) {
 		spin_lock(&dcache_lock);
 		spin_lock(&dentry->d_lock);
@@ -154,7 +154,7 @@ static void spufs_prune_dir(struct dentry *dir)
 		}
 	}
 	shrink_dcache_parent(dir);
-	up(&dir->d_inode->i_sem);
+	mutex_unlock(&dir->d_inode->i_mutex);
 }
 
 static int spufs_rmdir(struct inode *root, struct dentry *dir_dentry)
@@ -162,15 +162,15 @@ static int spufs_rmdir(struct inode *root, struct dentry *dir_dentry)
 	struct spu_context *ctx;
 
 	/* remove all entries */
-	down(&root->i_sem);
+	mutex_lock(&root->i_mutex);
 	spufs_prune_dir(dir_dentry);
-	up(&root->i_sem);
+	mutex_unlock(&root->i_mutex);
 
 	/* We have to give up the mm_struct */
 	ctx = SPUFS_I(dir_dentry->d_inode)->i_ctx;
 	spu_forget(ctx);
 
-	/* XXX Do we need to hold i_sem here ? */
+	/* XXX Do we need to hold i_mutex here ? */
 	return simple_rmdir(root, dir_dentry);
 }
 
@@ -330,7 +330,7 @@ long spufs_create_thread(struct nameidata *nd,
 out_dput:
 	dput(dentry);
 out_dir:
-	up(&nd->dentry->d_inode->i_sem);
+	mutex_unlock(&nd->dentry->d_inode->i_mutex);
 out:
 	return ret;
 }

drivers/block/loop.c

@@ -215,7 +215,7 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
 	unsigned offset, bv_offs;
 	int len, ret;
 
-	down(&mapping->host->i_sem);
+	mutex_lock(&mapping->host->i_mutex);
 	index = pos >> PAGE_CACHE_SHIFT;
 	offset = pos & ((pgoff_t)PAGE_CACHE_SIZE - 1);
 	bv_offs = bvec->bv_offset;
@@ -278,7 +278,7 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec,
 	}
 	ret = 0;
 out:
-	up(&mapping->host->i_sem);
+	mutex_unlock(&mapping->host->i_mutex);
 	return ret;
 unlock:
 	unlock_page(page);

drivers/char/mem.c

@@ -741,7 +741,7 @@ static loff_t memory_lseek(struct file * file, loff_t offset, int orig)
 {
 	loff_t ret;
 
-	down(&file->f_dentry->d_inode->i_sem);
+	mutex_lock(&file->f_dentry->d_inode->i_mutex);
 	switch (orig) {
 		case 0:
 			file->f_pos = offset;
@@ -756,7 +756,7 @@ static loff_t memory_lseek(struct file * file, loff_t offset, int orig)
 		default:
 			ret = -EINVAL;
 	}
-	up(&file->f_dentry->d_inode->i_sem);
+	mutex_unlock(&file->f_dentry->d_inode->i_mutex);
 	return ret;
 }
 

drivers/isdn/capi/capifs.c

@@ -138,7 +138,7 @@ static struct dentry *get_node(int num)
 {
 	char s[10];
 	struct dentry *root = capifs_root;
-	down(&root->d_inode->i_sem);
+	mutex_lock(&root->d_inode->i_mutex);
 	return lookup_one_len(s, root, sprintf(s, "%d", num));
 }
 
@@ -159,7 +159,7 @@ void capifs_new_ncci(unsigned int number, dev_t device)
 	dentry = get_node(number);
 	if (!IS_ERR(dentry) && !dentry->d_inode)
 		d_instantiate(dentry, inode);
-	up(&capifs_root->d_inode->i_sem);
+	mutex_unlock(&capifs_root->d_inode->i_mutex);
 }
 
 void capifs_free_ncci(unsigned int number)
@@ -175,7 +175,7 @@ void capifs_free_ncci(unsigned int number)
 		}
 		dput(dentry);
 	}
-	up(&capifs_root->d_inode->i_sem);
+	mutex_unlock(&capifs_root->d_inode->i_mutex);
 }
 
 static int __init capifs_init(void)

drivers/md/dm.c

@@ -837,9 +837,9 @@ static void __set_size(struct mapped_device *md, sector_t size)
 {
 	set_capacity(md->disk, size);
 
-	down(&md->suspended_bdev->bd_inode->i_sem);
+	mutex_lock(&md->suspended_bdev->bd_inode->i_mutex);
 	i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
-	up(&md->suspended_bdev->bd_inode->i_sem);
+	mutex_unlock(&md->suspended_bdev->bd_inode->i_mutex);
 }
 
 static int __bind(struct mapped_device *md, struct dm_table *t)

drivers/md/md.c

@@ -3460,9 +3460,9 @@ static int update_size(mddev_t *mddev, unsigned long size)
 
 		bdev = bdget_disk(mddev->gendisk, 0);
 		if (bdev) {
-			down(&bdev->bd_inode->i_sem);
+			mutex_lock(&bdev->bd_inode->i_mutex);
 			i_size_write(bdev->bd_inode, mddev->array_size << 10);
-			up(&bdev->bd_inode->i_sem);
+			mutex_unlock(&bdev->bd_inode->i_mutex);
 			bdput(bdev);
 		}
 	}
@@ -3486,9 +3486,9 @@ static int update_raid_disks(mddev_t *mddev, int raid_disks)
 
 		bdev = bdget_disk(mddev->gendisk, 0);
 		if (bdev) {
-			down(&bdev->bd_inode->i_sem);
+			mutex_lock(&bdev->bd_inode->i_mutex);
 			i_size_write(bdev->bd_inode, mddev->array_size << 10);
-			up(&bdev->bd_inode->i_sem);
+			mutex_unlock(&bdev->bd_inode->i_mutex);
 			bdput(bdev);
 		}
 	}

drivers/pci/proc.c

@@ -25,7 +25,7 @@ proc_bus_pci_lseek(struct file *file, loff_t off, int whence)
 	loff_t new = -1;
 	struct inode *inode = file->f_dentry->d_inode;
 
-	down(&inode->i_sem);
+	mutex_lock(&inode->i_mutex);
 	switch (whence) {
 	case 0:
 		new = off;
@@ -41,7 +41,7 @@ proc_bus_pci_lseek(struct file *file, loff_t off, int whence)
 		new = -EINVAL;
 	else
 		file->f_pos = new;
-	up(&inode->i_sem);
+	mutex_unlock(&inode->i_mutex);
 	return new;
 }
 

drivers/usb/core/inode.c

@@ -184,13 +184,13 @@ static void update_bus(struct dentry *bus)
 	bus->d_inode->i_gid = busgid;
 	bus->d_inode->i_mode = S_IFDIR | busmode;
 
-	down(&bus->d_inode->i_sem);
+	mutex_lock(&bus->d_inode->i_mutex);
 
 	list_for_each_entry(dev, &bus->d_subdirs, d_u.d_child)
 		if (dev->d_inode)
 			update_dev(dev);
 
-	up(&bus->d_inode->i_sem);
+	mutex_unlock(&bus->d_inode->i_mutex);
 }
 
 static void update_sb(struct super_block *sb)
@@ -201,7 +201,7 @@ static void update_sb(struct super_block *sb)
 	if (!root)
 		return;
 
-	down(&root->d_inode->i_sem);
+	mutex_lock(&root->d_inode->i_mutex);
 
 	list_for_each_entry(bus, &root->d_subdirs, d_u.d_child) {
 		if (bus->d_inode) {
@@ -219,7 +219,7 @@ static void update_sb(struct super_block *sb)
 		}
 	}
 
-	up(&root->d_inode->i_sem);
+	mutex_unlock(&root->d_inode->i_mutex);
 }
 
 static int remount(struct super_block *sb, int *flags, char *data)
@@ -333,10 +333,10 @@ static int usbfs_empty (struct dentry *dentry)
 static int usbfs_unlink (struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode = dentry->d_inode;
-	down(&inode->i_sem);
+	mutex_lock(&inode->i_mutex);
 	dentry->d_inode->i_nlink--;
 	dput(dentry);
-	up(&inode->i_sem);
+	mutex_unlock(&inode->i_mutex);
 	d_delete(dentry);
 	return 0;
 }
@@ -346,7 +346,7 @@ static int usbfs_rmdir(struct inode *dir, struct dentry *dentry)
 	int error = -ENOTEMPTY;
 	struct inode * inode = dentry->d_inode;
 
-	down(&inode->i_sem);
+	mutex_lock(&inode->i_mutex);
 	dentry_unhash(dentry);
 	if (usbfs_empty(dentry)) {
 		dentry->d_inode->i_nlink -= 2;
@@ -355,7 +355,7 @@ static int usbfs_rmdir(struct inode *dir, struct dentry *dentry)
 		dir->i_nlink--;
 		error = 0;
 	}
-	up(&inode->i_sem);
+	mutex_unlock(&inode->i_mutex);
 	if (!error)
 		d_delete(dentry);
 	dput(dentry);
@@ -380,7 +380,7 @@ static loff_t default_file_lseek (struct file *file, loff_t offset, int orig)
 {
 	loff_t retval = -EINVAL;
 
-	down(&file->f_dentry->d_inode->i_sem);
+	mutex_lock(&file->f_dentry->d_inode->i_mutex);
 	switch(orig) {
 	case 0:
 		if (offset > 0) {
@@ -397,7 +397,7 @@ static loff_t default_file_lseek (struct file *file, loff_t offset, int orig)
 	default:
 		break;
 	}
-	up(&file->f_dentry->d_inode->i_sem);
+	mutex_unlock(&file->f_dentry->d_inode->i_mutex);
 	return retval;
 }
 
@@ -480,7 +480,7 @@ static int fs_create_by_name (const char *name, mode_t mode,
 	}
 
 	*dentry = NULL;
-	down(&parent->d_inode->i_sem);
+	mutex_lock(&parent->d_inode->i_mutex);
 	*dentry = lookup_one_len(name, parent, strlen(name));
 	if (!IS_ERR(dentry)) {
 		if ((mode & S_IFMT) == S_IFDIR)
@@ -489,7 +489,7 @@ static int fs_create_by_name (const char *name, mode_t mode,
 			error = usbfs_create (parent->d_inode, *dentry, mode);
 	} else
 		error = PTR_ERR(dentry);
-	up(&parent->d_inode->i_sem);
+	mutex_unlock(&parent->d_inode->i_mutex);
 
 	return error;
 }
@@ -528,7 +528,7 @@ static void fs_remove_file (struct dentry *dentry)
 	if (!parent || !parent->d_inode)
 		return;
 
-	down(&parent->d_inode->i_sem);
+	mutex_lock(&parent->d_inode->i_mutex);
 	if (usbfs_positive(dentry)) {
 		if (dentry->d_inode) {
 			if (S_ISDIR(dentry->d_inode->i_mode))
@@ -538,7 +538,7 @@ static void fs_remove_file (struct dentry *dentry)
 		dput(dentry);
 		}
 	}
-	up(&parent->d_inode->i_sem);
+	mutex_unlock(&parent->d_inode->i_mutex);
 }
 
 /* --------------------------------------------------------------------- */

drivers/usb/gadget/file_storage.c

@@ -1891,7 +1891,7 @@ static int fsync_sub(struct lun *curlun)
 		return -EINVAL;
 
 	inode = filp->f_dentry->d_inode;
-	down(&inode->i_sem);
+	mutex_lock(&inode->i_mutex);
 	current->flags |= PF_SYNCWRITE;
 	rc = filemap_fdatawrite(inode->i_mapping);
 	err = filp->f_op->fsync(filp, filp->f_dentry, 1);
@@ -1901,7 +1901,7 @@ static int fsync_sub(struct lun *curlun)
 	if (!rc)
 		rc = err;
 	current->flags &= ~PF_SYNCWRITE;
-	up(&inode->i_sem);
+	mutex_unlock(&inode->i_mutex);
 	VLDBG(curlun, "fdatasync -> %d\n", rc);
 	return rc;
 }

drivers/usb/gadget/inode.c

@@ -1562,10 +1562,10 @@ restart:
 		spin_unlock_irq (&dev->lock);
 
 		/* break link to dcache */
-		down (&parent->i_sem);
+		mutex_lock (&parent->i_mutex);
 		d_delete (dentry);
 		dput (dentry);
-		up (&parent->i_sem);
+		mutex_unlock (&parent->i_mutex);
 
 		/* fds may still be open */
 		goto restart;

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);
 	}
 }
 

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

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);
 	}
 
 	/*

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;
 	}

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;
 }
 	

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);

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));

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);

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;
 }

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 ) {