Commit 3a27411c authored by Andreas Gruenbacher's avatar Andreas Gruenbacher
Browse files

gfs2: Implement SEEK_HOLE / SEEK_DATA via iomap 



So far, lseek on gfs2 did not report holes.

Signed-off-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: default avatarBob Peterson <rpeterso@redhat.com>
parent aac1a55b

fs/gfs2/file.c

+14 −3
Original line number Diff line number Diff line
@@ -60,9 +60,7 @@ static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence) 
	loff_t error;



	switch (whence) {

	case SEEK_END: /* These reference inode->i_size */

	case SEEK_DATA:

	case SEEK_HOLE:

	case SEEK_END:

		error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,

					   &i_gh);

		if (!error) {
@@ -70,8 +68,21 @@ static loff_t gfs2_llseek(struct file *file, loff_t offset, int whence) 
			gfs2_glock_dq_uninit(&i_gh);

		}

		break;



	case SEEK_DATA:

		error = gfs2_seek_data(file, offset);

		break;



	case SEEK_HOLE:

		error = gfs2_seek_hole(file, offset);

		break;



	case SEEK_CUR:

	case SEEK_SET:

		/*

		 * These don't reference inode->i_size and don't depend on the

		 * block mapping, so we don't need the glock.

		 */

		error = generic_file_llseek(file, offset, whence);

		break;

	default:

fs/gfs2/inode.c

+38 −0
Original line number Diff line number Diff line
@@ -2029,6 +2029,44 @@ static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, 
	return ret;

}



loff_t gfs2_seek_data(struct file *file, loff_t offset)

{

	struct inode *inode = file->f_mapping->host;

	struct gfs2_inode *ip = GFS2_I(inode);

	struct gfs2_holder gh;

	loff_t ret;



	inode_lock_shared(inode);

	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);

	if (!ret)

		ret = iomap_seek_data(inode, offset, &gfs2_iomap_ops);

	gfs2_glock_dq_uninit(&gh);

	inode_unlock_shared(inode);



	if (ret < 0)

		return ret;

	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);

}



loff_t gfs2_seek_hole(struct file *file, loff_t offset)

{

	struct inode *inode = file->f_mapping->host;

	struct gfs2_inode *ip = GFS2_I(inode);

	struct gfs2_holder gh;

	loff_t ret;



	inode_lock_shared(inode);

	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);

	if (!ret)

		ret = iomap_seek_hole(inode, offset, &gfs2_iomap_ops);

	gfs2_glock_dq_uninit(&gh);

	inode_unlock_shared(inode);



	if (ret < 0)

		return ret;

	return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);

}



const struct inode_operations gfs2_file_iops = {

	.permission = gfs2_permission,

	.setattr = gfs2_setattr,

fs/gfs2/inode.h

+2 −0
Original line number Diff line number Diff line
@@ -109,6 +109,8 @@ extern int gfs2_setattr_simple(struct inode *inode, struct iattr *attr); 
extern struct inode *gfs2_lookup_simple(struct inode *dip, const char *name);

extern void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf);

extern int gfs2_open_common(struct inode *inode, struct file *file);

extern loff_t gfs2_seek_data(struct file *file, loff_t offset);

extern loff_t gfs2_seek_hole(struct file *file, loff_t offset);



extern const struct inode_operations gfs2_file_iops;

extern const struct inode_operations gfs2_dir_iops;