gfs2: Implement SEEK_HOLE / SEEK_DATA via iomap

So far, lseek on gfs2 did not report holes.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
This commit is contained in:
Andreas Gruenbacher 2017-03-15 19:12:59 +01:00
parent aac1a55b45
commit 3a27411cb4
3 changed files with 54 additions and 3 deletions

View File

@ -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:

View File

@ -2029,6 +2029,44 @@ out:
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,

View File

@ -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;