Commit 72558e2b authored by Gao Xiang's avatar Gao Xiang
Browse files

erofs: use inode_set_cached_link() 



Symlink lengths are now cached in in-memory inodes directly so that
readlink can be sped up.

Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
parent 1729f7c6

fs/erofs/inode.c

+21 −13
Original line number Diff line number Diff line
@@ -8,21 +8,29 @@ 
#include <linux/compat.h>

#include <trace/events/erofs.h>



static int erofs_fill_symlink(struct inode *inode, void *kaddr,

			      unsigned int m_pofs)

static int erofs_fill_symlink(struct inode *inode, void *bptr, unsigned int ofs)

{

	struct erofs_inode *vi = EROFS_I(inode);

	loff_t off;



	m_pofs += vi->xattr_isize;

	/* check if it cannot be handled with fast symlink scheme */

	if (vi->datalayout != EROFS_INODE_FLAT_INLINE ||

	    check_add_overflow(m_pofs, inode->i_size, &off) ||

	    off > i_blocksize(inode))

	char *link;

	loff_t end;



	ofs += vi->xattr_isize;

	/* check whether the symlink data is small enough to be inlined */

	if (vi->datalayout == EROFS_INODE_FLAT_INLINE &&

	    !check_add_overflow(ofs, inode->i_size, &end) &&

	    end <= i_blocksize(inode)) {

		link = kmemdup_nul(bptr + ofs, inode->i_size, GFP_KERNEL);

		if (!link)

			return -ENOMEM;

		if (unlikely(!inode->i_size || strlen(link) != inode->i_size)) {

			erofs_err(inode->i_sb, "invalid fast symlink size %llu @ nid %llu",

				  inode->i_size | 0ULL, vi->nid);

			kfree(link);

			return -EFSCORRUPTED;

		}

		inode_set_cached_link(inode, link, inode->i_size);

	}

	return 0;



	inode->i_link = kmemdup_nul(kaddr + m_pofs, inode->i_size, GFP_KERNEL);

	return inode->i_link ? 0 : -ENOMEM;

}



static int erofs_read_inode(struct inode *inode)