ceph: fix ceph_dir_llseek()

Comparing offset with inode->i_sb->s_maxbytes doesn't make sense for
directory. For a fragmented directory, offset (frag_t, off) can be
larger than inode->i_sb->s_maxbytes.

At the very beginning of ceph_dir_llseek(), local variable old_offset
is initialized to parameter offset. This doesn't make sense neither.
Old_offset should be ceph_make_fpos(fi->frag, fi->next_offset).

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Alex Elder <elder@linaro.org>

1 files changed, 6 insertions, 6 deletions

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 45eda6d7a40c..a7eaf9692aa6 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -190,7 +190,7 @@ more:
                 if (last) {
                         /* remember our position */
                         fi->dentry = last;
-                        fi->next_offset = di->offset;
+                        fi->next_offset = fpos_off(di->offset);
                 }
                 dput(dentry);
                 return 0;
@@ -369,9 +369,9 @@ more:
                                 fi->next_offset = 0;
                         off = fi->next_offset;
                 }
+                fi->frag = frag;
                 fi->offset = fi->next_offset;
                 fi->last_readdir = req;
-                fi->frag = frag;
 
                 if (req->r_reply_info.dir_end) {
                         kfree(fi->last_name);
@@ -474,7 +474,7 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
 {
         struct ceph_file_info *fi = file->private_data;
         struct inode *inode = file->f_mapping->host;
-        loff_t old_offset = offset;
+        loff_t old_offset = ceph_make_fpos(fi->frag, fi->next_offset);
         loff_t retval;
 
         mutex_lock(&inode->i_mutex);
@@ -491,7 +491,7 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
                 goto out;
         }
 
-        if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) {
+        if (offset >= 0) {
                 if (offset != file->f_pos) {
                         file->f_pos = offset;
                         file->f_version = 0;
@@ -504,14 +504,14 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
                  * seek to new frag, or seek prior to current chunk.
                  */
                 if (offset == 0 ||
-                    fpos_frag(offset) != fpos_frag(old_offset) ||
+                    fpos_frag(offset) != fi->frag ||
                     fpos_off(offset) < fi->offset) {
                         dout("dir_llseek dropping %p content\n", file);
                         reset_readdir(fi);
                 }
 
                 /* bump dir_release_count if we did a forward seek */
-                if (offset > old_offset)
+                if (fpos_cmp(offset, old_offset) > 0)
                         fi->dir_release_count--;
         }
 out: