fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek

This converts everybody to handle SEEK_HOLE/SEEK_DATA properly.  In some cases
we just return -EINVAL, in others we do the normal generic thing, and in others
we're simply making sure that the properly due-dilligence is done.  For example
in NFS/CIFS we need to make sure the file size is update properly for the
SEEK_HOLE and SEEK_DATA case, but since it calls the generic llseek stuff itself
that is all we have to do.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 18 insertions, 2 deletions

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 0a292459c895..0d0eae05598f 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -768,13 +768,16 @@ static loff_t ceph_llseek(struct file *file, loff_t offset, int origin)
 
         mutex_lock(&inode->i_mutex);
         __ceph_do_pending_vmtruncate(inode);
-        switch (origin) {
-        case SEEK_END:
+        if (origin != SEEK_CUR || origin != SEEK_SET) {
                 ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
                 if (ret < 0) {
                         offset = ret;
                         goto out;
                 }
+        }
+
+        switch (origin) {
+        case SEEK_END:
                 offset += inode->i_size;
                 break;
         case SEEK_CUR:
@@ -790,6 +793,19 @@ static loff_t ceph_llseek(struct file *file, loff_t offset, int origin)
                 }
                 offset += file->f_pos;
                 break;
+        case SEEK_DATA:
+                if (offset >= inode->i_size) {
+                        ret = -ENXIO;
+                        goto out;
+                }
+                break;
+        case SEEK_HOLE:
+                if (offset >= inode->i_size) {
+                        ret = -ENXIO;
+                        goto out;
+                }
+                offset = inode->i_size;
+                break;
         }
 
         if (offset < 0 || offset > inode->i_sb->s_maxbytes) {