Commit ea022dfb authored by Al Viro's avatar Al Viro
Browse files

ocfs: simplify symlink handling 



seeing that "fast" symlinks still get allocation + copy, we might as
well simply switch them to pagecache-based variant of ->follow_link();
just need an appropriate ->readpage() for them...

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 408bd629

fs/ocfs2/inode.c

+6 −7
Original line number Diff line number Diff line
@@ -273,11 +273,13 @@ void ocfs2_populate_inode(struct inode *inode, struct ocfs2_dinode *fe, 
	inode->i_gid = le32_to_cpu(fe->i_gid);



	/* Fast symlinks will have i_size but no allocated clusters. */

	if (S_ISLNK(inode->i_mode) && !fe->i_clusters)

	if (S_ISLNK(inode->i_mode) && !fe->i_clusters) {

		inode->i_blocks = 0;

	else

		inode->i_mapping->a_ops = &ocfs2_fast_symlink_aops;

	} else {

		inode->i_blocks = ocfs2_inode_sector_count(inode);

		inode->i_mapping->a_ops = &ocfs2_aops;

	}

	inode->i_atime.tv_sec = le64_to_cpu(fe->i_atime);

	inode->i_atime.tv_nsec = le32_to_cpu(fe->i_atime_nsec);

	inode->i_mtime.tv_sec = le64_to_cpu(fe->i_mtime);
@@ -331,9 +333,6 @@ void ocfs2_populate_inode(struct inode *inode, struct ocfs2_dinode *fe, 
		    OCFS2_I(inode)->ip_dir_lock_gen = 1;

		    break;

	    case S_IFLNK:

		    if (ocfs2_inode_is_fast_symlink(inode))

			inode->i_op = &ocfs2_fast_symlink_inode_operations;

		    else

		    inode->i_op = &ocfs2_symlink_inode_operations;

		    i_size_write(inode, le64_to_cpu(fe->i_size));

		    break;

fs/ocfs2/namei.c

+3 −2
Original line number Diff line number Diff line
@@ -1724,15 +1724,16 @@ static int ocfs2_symlink(struct inode *dir, 
	fe = (struct ocfs2_dinode *) new_fe_bh->b_data;

	inode->i_rdev = 0;

	newsize = l - 1;

	inode->i_op = &ocfs2_symlink_inode_operations;

	if (l > ocfs2_fast_symlink_chars(sb)) {

		u32 offset = 0;



		inode->i_op = &ocfs2_symlink_inode_operations;

		status = dquot_alloc_space_nodirty(inode,

		    ocfs2_clusters_to_bytes(osb->sb, 1));

		if (status)

			goto bail;

		did_quota = 1;

		inode->i_mapping->a_ops = &ocfs2_aops;

		status = ocfs2_add_inode_data(osb, inode, &offset, 1, 0,

					      new_fe_bh,

					      handle, data_ac, NULL,
@@ -1750,7 +1751,7 @@ static int ocfs2_symlink(struct inode *dir, 
		i_size_write(inode, newsize);

		inode->i_blocks = ocfs2_inode_sector_count(inode);

	} else {

		inode->i_op = &ocfs2_fast_symlink_inode_operations;

		inode->i_mapping->a_ops = &ocfs2_fast_symlink_aops;

		memcpy((char *) fe->id2.i_symlink, symname, l);

		i_size_write(inode, newsize);

		inode->i_blocks = 0;

fs/ocfs2/symlink.c

+21 −94
Original line number Diff line number Diff line
@@ -54,101 +54,40 @@ 
#include "buffer_head_io.h"





static char *ocfs2_fast_symlink_getlink(struct inode *inode,

					struct buffer_head **bh)

static int ocfs2_fast_symlink_readpage(struct file *unused, struct page *page)

{

	int status;

	char *link = NULL;

	struct inode *inode = page->mapping->host;

	struct buffer_head *bh;

	int status = ocfs2_read_inode_block(inode, &bh);

	struct ocfs2_dinode *fe;

	const char *link;

	void *kaddr;

	size_t len;



	status = ocfs2_read_inode_block(inode, bh);

	if (status < 0) {

		mlog_errno(status);

		link = ERR_PTR(status);

		goto bail;

		return status;

	}



	fe = (struct ocfs2_dinode *) (*bh)->b_data;

	fe = (struct ocfs2_dinode *) bh->b_data;

	link = (char *) fe->id2.i_symlink;

bail:



	return link;

}



static int ocfs2_readlink(struct dentry *dentry,

			  char __user *buffer,

			  int buflen)

{

	int ret;

	char *link;

	struct buffer_head *bh = NULL;

	struct inode *inode = dentry->d_inode;



	link = ocfs2_fast_symlink_getlink(inode, &bh);

	if (IS_ERR(link)) {

		ret = PTR_ERR(link);

		goto out;

	}



	/*

	 * Without vfsmount we can't update atime now,

	 * but we will update atime here ultimately.

	 */

	ret = vfs_readlink(dentry, buffer, buflen, link);



	brelse(bh);

out:

	if (ret < 0)

		mlog_errno(ret);

	return ret;

}



static void *ocfs2_fast_follow_link(struct dentry *dentry,

				    struct nameidata *nd)

{

	int status = 0;

	int len;

	char *target, *link = ERR_PTR(-ENOMEM);

	struct inode *inode = dentry->d_inode;

	struct buffer_head *bh = NULL;



	BUG_ON(!ocfs2_inode_is_fast_symlink(inode));

	target = ocfs2_fast_symlink_getlink(inode, &bh);

	if (IS_ERR(target)) {

		status = PTR_ERR(target);

		mlog_errno(status);

		goto bail;

	}



	/* Fast symlinks can't be large */

	len = strnlen(target, ocfs2_fast_symlink_chars(inode->i_sb));

	link = kzalloc(len + 1, GFP_NOFS);

	if (!link) {

		status = -ENOMEM;

		mlog_errno(status);

		goto bail;

	}



	memcpy(link, target, len);



bail:

	nd_set_link(nd, status ? ERR_PTR(status) : link);

	/* will be less than a page size */

	len = strnlen(link, ocfs2_fast_symlink_chars(inode->i_sb));

	kaddr = kmap_atomic(page);

	memcpy(kaddr, link, len + 1);

	kunmap_atomic(kaddr);

	SetPageUptodate(page);

	unlock_page(page);

	brelse(bh);



	if (status)

		mlog_errno(status);

	return NULL;

	return 0;

}



static void ocfs2_fast_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie)

{

	char *link = nd_get_link(nd);

	if (!IS_ERR(link))

		kfree(link);

}

const struct address_space_operations ocfs2_fast_symlink_aops = {

	.readpage		= ocfs2_fast_symlink_readpage,

};



const struct inode_operations ocfs2_symlink_inode_operations = {

	.readlink	= page_readlink,

	.readlink	= generic_readlink,

	.follow_link	= page_follow_link_light,

	.put_link	= page_put_link,

	.getattr	= ocfs2_getattr,
@@ -159,15 +98,3 @@ const struct inode_operations ocfs2_symlink_inode_operations = { 
	.removexattr	= generic_removexattr,

	.fiemap		= ocfs2_fiemap,

};
 
const struct inode_operations ocfs2_fast_symlink_inode_operations = {

	.readlink	= ocfs2_readlink,

	.follow_link	= ocfs2_fast_follow_link,

	.put_link	= ocfs2_fast_put_link,

	.getattr	= ocfs2_getattr,

	.setattr	= ocfs2_setattr,

	.setxattr	= generic_setxattr,

	.getxattr	= generic_getxattr,

	.listxattr	= ocfs2_listxattr,

	.removexattr	= generic_removexattr,

	.fiemap		= ocfs2_fiemap,

};

fs/ocfs2/symlink.h

+1 −1
Original line number Diff line number Diff line
@@ -27,7 +27,7 @@ 
#define OCFS2_SYMLINK_H



extern const struct inode_operations ocfs2_symlink_inode_operations;

extern const struct inode_operations ocfs2_fast_symlink_inode_operations;

extern const struct address_space_operations ocfs2_fast_symlink_aops;



/*

 * Test whether an inode is a fast symlink.

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