3 files changed, 32 insertions, 11 deletions

diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 330f6259bb6d..5b1751d81901 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -174,6 +174,7 @@ struct smb_vol;
 struct cifs_fid;
 struct cifs_readdata;
 struct cifs_writedata;
+struct cifs_io_parms;
 
 struct smb_version_operations {
         int (*send_cancel)(struct TCP_Server_Info *, void *,
@@ -286,6 +287,10 @@ struct smb_version_operations {
         int (*async_readv)(struct cifs_readdata *);
         /* async write to the server */
         int (*async_writev)(struct cifs_writedata *);
+        /* sync read from the server */
+        int (*sync_read)(const unsigned int, struct cifsFileInfo *,
+                         struct cifs_io_parms *, unsigned int *, char **,
+                         int *);
 };
 
 struct smb_version_values {
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 703c1648b068..fae03c52f314 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2782,8 +2782,8 @@ ssize_t cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
         return cifs_user_readv(iocb, iov, nr_segs, pos);
 }
 
-static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
-                         loff_t *poffset)
+static ssize_t
+cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
 {
         int rc = -EACCES;
         unsigned int bytes_read = 0;
@@ -2792,8 +2792,9 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
         unsigned int rsize;
         struct cifs_sb_info *cifs_sb;
         struct cifs_tcon *tcon;
+        struct TCP_Server_Info *server;
         unsigned int xid;
-        char *current_offset;
+        char *cur_offset;
         struct cifsFileInfo *open_file;
         struct cifs_io_parms io_parms;
         int buf_type = CIFS_NO_BUFFER;
@@ -2812,6 +2813,12 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
         }
         open_file = file->private_data;
         tcon = tlink_tcon(open_file->tlink);
+        server = tcon->ses->server;
+
+        if (!server->ops->sync_read) {
+                free_xid(xid);
+                return -ENOSYS;
+        }
 
         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
                 pid = open_file->pid;
@@ -2821,9 +2828,8 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
         if ((file->f_flags & O_ACCMODE) == O_WRONLY)
                 cFYI(1, "attempting read on write only file instance");
 
-        for (total_read = 0, current_offset = read_data;
-             read_size > total_read;
-             total_read += bytes_read, current_offset += bytes_read) {
+        for (total_read = 0, cur_offset = read_data; read_size > total_read;
+             total_read += bytes_read, cur_offset += bytes_read) {
                 current_read_size = min_t(uint, read_size - total_read, rsize);
                 /*
                  * For windows me and 9x we do not want to request more than it
@@ -2841,13 +2847,13 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
                                 if (rc != 0)
                                         break;
                         }
-                        io_parms.netfid = open_file->fid.netfid;
                         io_parms.pid = pid;
                         io_parms.tcon = tcon;
-                        io_parms.offset = *poffset;
+                        io_parms.offset = *offset;
                         io_parms.length = current_read_size;
-                        rc = CIFSSMBRead(xid, &io_parms, &bytes_read,
-                                         &current_offset, &buf_type);
+                        rc = server->ops->sync_read(xid, open_file, &io_parms,
+                                                    &bytes_read, &cur_offset,
+                                                    &buf_type);
                 }
                 if (rc || (bytes_read == 0)) {
                         if (total_read) {
@@ -2858,7 +2864,7 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
                         }
                 } else {
                         cifs_stats_bytes_read(tcon, total_read);
-                        *poffset += bytes_read;
+                        *offset += bytes_read;
                 }
         }
         free_xid(xid);
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index 50c3697af5aa..cea958ee8b7a 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -739,6 +739,15 @@ cifs_flush_file(const unsigned int xid, struct cifs_tcon *tcon,
         return CIFSSMBFlush(xid, tcon, fid->netfid);
 }
 
+static int
+cifs_sync_read(const unsigned int xid, struct cifsFileInfo *cfile,
+               struct cifs_io_parms *parms, unsigned int *bytes_read,
+               char **buf, int *buf_type)
+{
+        parms->netfid = cfile->fid.netfid;
+        return CIFSSMBRead(xid, parms, bytes_read, buf, buf_type);
+}
+
 struct smb_version_operations smb1_operations = {
         .send_cancel = send_nt_cancel,
         .compare_fids = cifs_compare_fids,
@@ -787,6 +796,7 @@ struct smb_version_operations smb1_operations = {
         .flush = cifs_flush_file,
         .async_readv = cifs_async_readv,
         .async_writev = cifs_async_writev,
+        .sync_read = cifs_sync_read,
 };
 
 struct smb_version_values smb1_values = {