pstore: fix pstore filesystem mount/remount issue

Currently after mount/remount operation on pstore filesystem,
the content on pstore will be lost. It is because current ERST
implementation doesn't support multi-user usage, which moves
internal pointer to the end after accessing it. Adding
multi-user support for pstore usage.

Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 912403c2a93..f2c3ff20ea6 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -156,17 +156,23 @@ void pstore_get_records(void)
         u64                     id;
         enum pstore_type_id     type;
         struct timespec         time;
-        int                     failed = 0;
+        int                     failed = 0, rc;
 
         if (!psi)
                 return;
 
         mutex_lock(&psinfo->buf_mutex);
+        rc = psi->open(psi);
+        if (rc)
+                goto out;
+
         while ((size = psi->read(&id, &type, &time)) > 0) {
                 if (pstore_mkfile(type, psi->name, id, psi->buf, (size_t)size,
                                   time, psi->erase))
                         failed++;
         }
+        psi->close(psi);
+out:
         mutex_unlock(&psinfo->buf_mutex);
 
         if (failed)