From: Paulo Alcantara pc@cjr.nz
commit 5d7e282541fc91b831a5c4477c5d72881c623df9 upstream.
When I/O fails in one of the currently connected DFS targets, retry it from other targets as specified in MS-DFSC "3.1.5.2 I/O Operation to +Target Fails with an Error Other Than STATUS_PATH_NOT_COVERED."
Signed-off-by: Paulo Alcantara (SUSE) pc@cjr.nz Cc: stable@vger.kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/cifs/connect.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)
--- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -3473,6 +3473,9 @@ static int connect_dfs_target(struct mou struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb; char *oldmnt = cifs_sb->ctx->mount_options;
+ cifs_dbg(FYI, "%s: full_path=%s ref_path=%s target=%s\n", __func__, full_path, ref_path, + dfs_cache_get_tgt_name(tit)); + rc = dfs_cache_get_tgt_referral(ref_path, tit, &ref); if (rc) goto out; @@ -3571,13 +3574,18 @@ static int __follow_dfs_link(struct moun if (rc) goto out;
- /* Try all dfs link targets */ + /* Try all dfs link targets. If an I/O fails from currently connected DFS target with an + * error other than STATUS_PATH_NOT_COVERED (-EREMOTE), then retry it from other targets as + * specified in MS-DFSC "3.1.5.2 I/O Operation to Target Fails with an Error Other Than + * STATUS_PATH_NOT_COVERED." + */ for (rc = -ENOENT, tit = dfs_cache_get_tgt_iterator(&tl); tit; tit = dfs_cache_get_next_tgt(&tl, tit)) { rc = connect_dfs_target(mnt_ctx, full_path, mnt_ctx->leaf_fullpath + 1, tit); if (!rc) { rc = is_path_remote(mnt_ctx); - break; + if (!rc || rc == -EREMOTE) + break; } }
@@ -3651,7 +3659,7 @@ int cifs_mount(struct cifs_sb_info *cifs goto error;
rc = is_path_remote(&mnt_ctx); - if (rc == -EREMOTE) + if (rc) rc = follow_dfs_link(&mnt_ctx); if (rc) goto error;