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, 19 insertions, 2 deletions

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 82a66466a24c..73b89df20851 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1600,15 +1600,32 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin)
         struct inode *inode = file->f_path.dentry->d_inode;
 
         mutex_lock(&inode->i_mutex);
-        switch (origin) {
-        case SEEK_END:
+        if (origin != SEEK_CUR || origin != SEEK_SET) {
                 retval = fuse_update_attributes(inode, NULL, file, NULL);
                 if (retval)
                         goto exit;
+        }
+
+        switch (origin) {
+        case SEEK_END:
                 offset += i_size_read(inode);
                 break;
         case SEEK_CUR:
                 offset += file->f_pos;
+                break;
+        case SEEK_DATA:
+                if (offset >= i_size_read(inode)) {
+                        retval = -ENXIO;
+                        goto exit;
+                }
+                break;
+        case SEEK_HOLE:
+                if (offset >= i_size_read(inode)) {
+                        retval = -ENXIO;
+                        goto exit;
+                }
+                offset = i_size_read(inode);
+                break;
         }
         retval = -EINVAL;
         if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) {