Commit d769b3c2 authored by Jan Kara's avatar Jan Kara Committed by Al Viro
Browse files

isofs: Remove global fs lock 



sbi->s_mutex isn't needed for isofs at all so we can just remove it. Generally,
since isofs is always mounted read-only, filesystem structure cannot change
under us.  So buffer_head contents stays constant after it's filled in. That
leaves us with possible changes of global data structures. Superblock changes
only during filesystem mount (even remount does not change it), inodes are only
filled in during reading from disk. So there are no changes of these structures
to bother about.

Arguments why sbi->s_mutex can be removed at each place:
isofs_readdir: Accesses sb, inode, filp, local variables => s_mutex not needed
isofs_lookup: Protected by directory's i_mutex. Accesses sb, inode, dentry,
  local variables => s_mutex not needed
rock_ridge_symlink_readpage: Protected by page lock. Accesses sb, inode,
  local variables => s_mutex not needed.

Signed-off-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 22ba747f

fs/isofs/dir.c

+0 −3
Original line number Diff line number Diff line
@@ -254,19 +254,16 @@ static int isofs_readdir(struct file *filp, 
	char *tmpname;

	struct iso_directory_record *tmpde;

	struct inode *inode = filp->f_path.dentry->d_inode;

	struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb);



	tmpname = (char *)__get_free_page(GFP_KERNEL);

	if (tmpname == NULL)

		return -ENOMEM;



	mutex_lock(&sbi->s_mutex);

	tmpde = (struct iso_directory_record *) (tmpname+1024);



	result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde);



	free_page((unsigned long) tmpname);

	mutex_unlock(&sbi->s_mutex);

	return result;

}

fs/isofs/inode.c

+0 −1
Original line number Diff line number Diff line
@@ -863,7 +863,6 @@ root_found: 
	sbi->s_utf8 = opt.utf8;

	sbi->s_nocompress = opt.nocompress;

	sbi->s_overriderockperm = opt.overriderockperm;

	mutex_init(&sbi->s_mutex);

	/*

	 * It would be incredibly stupid to allow people to mark every file

	 * on the disk as suid, so we merely allow them to set the default

fs/isofs/isofs.h

+0 −1
Original line number Diff line number Diff line
@@ -55,7 +55,6 @@ struct isofs_sb_info { 
	gid_t s_gid;

	uid_t s_uid;

	struct nls_table *s_nls_iocharset; /* Native language support table */

	struct mutex s_mutex; /* replaces BKL, please remove if possible */

};



#define ISOFS_INVALID_MODE ((mode_t) -1)

fs/isofs/namei.c

+0 −4
Original line number Diff line number Diff line
@@ -168,7 +168,6 @@ struct dentry *isofs_lookup(struct inode *dir, struct dentry *dentry, struct nam 
	int found;

	unsigned long uninitialized_var(block);

	unsigned long uninitialized_var(offset);

	struct isofs_sb_info *sbi = ISOFS_SB(dir->i_sb);

	struct inode *inode;

	struct page *page;
@@ -176,7 +175,6 @@ struct dentry *isofs_lookup(struct inode *dir, struct dentry *dentry, struct nam 
	if (!page)

		return ERR_PTR(-ENOMEM);



	mutex_lock(&sbi->s_mutex);

	found = isofs_find_entry(dir, dentry,

				&block, &offset,

				page_address(page),
@@ -185,7 +183,5 @@ struct dentry *isofs_lookup(struct inode *dir, struct dentry *dentry, struct nam 


	inode = found ? isofs_iget(dir->i_sb, block, offset) : NULL;



	mutex_unlock(&sbi->s_mutex);



	return d_splice_alias(inode, dentry);

}

fs/isofs/rock.c

+0 −3
Original line number Diff line number Diff line
@@ -678,7 +678,6 @@ static int rock_ridge_symlink_readpage(struct file *file, struct page *page) 


	init_rock_state(&rs, inode);

	block = ei->i_iget5_block;

	mutex_lock(&sbi->s_mutex);

	bh = sb_bread(inode->i_sb, block);

	if (!bh)

		goto out_noread;
@@ -748,7 +747,6 @@ repeat: 
		goto fail;

	brelse(bh);

	*rpnt = '\0';

	mutex_unlock(&sbi->s_mutex);

	SetPageUptodate(page);

	kunmap(page);

	unlock_page(page);
@@ -765,7 +763,6 @@ out_bad_span: 
	printk("symlink spans iso9660 blocks\n");

fail:

	brelse(bh);

	mutex_unlock(&sbi->s_mutex);

error:

	SetPageError(page);

	kunmap(page);

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