Merge branches 'topic/asoc', 'topic/misc-fixes', 'topic/ps3-csbits' and 'topic/stagin...
[cascardo/linux.git] / fs / ocfs2 / stack_user.c
index bd7e0f3..faec2d8 100644 (file)
@@ -28,6 +28,7 @@
 #include "ocfs2.h"  /* For struct ocfs2_lock_res */
 #include "stackglue.h"
 
+#include <linux/dlm_plock.h>
 
 /*
  * The control protocol starts with a handshake.  Until the handshake
@@ -550,26 +551,17 @@ static ssize_t ocfs2_control_read(struct file *file,
                                  size_t count,
                                  loff_t *ppos)
 {
-       char *proto_string = OCFS2_CONTROL_PROTO;
-       size_t to_write = 0;
-
-       if (*ppos >= OCFS2_CONTROL_PROTO_LEN)
-               return 0;
-
-       to_write = OCFS2_CONTROL_PROTO_LEN - *ppos;
-       if (to_write > count)
-               to_write = count;
-       if (copy_to_user(buf, proto_string + *ppos, to_write))
-               return -EFAULT;
+       ssize_t ret;
 
-       *ppos += to_write;
+       ret = simple_read_from_buffer(buf, count, ppos,
+                       OCFS2_CONTROL_PROTO, OCFS2_CONTROL_PROTO_LEN);
 
        /* Have we read the whole protocol list? */
-       if (*ppos >= OCFS2_CONTROL_PROTO_LEN)
+       if (ret > 0 && *ppos >= OCFS2_CONTROL_PROTO_LEN)
                ocfs2_control_set_handshake_state(file,
                                                  OCFS2_CONTROL_HANDSHAKE_READ);
 
-       return to_write;
+       return ret;
 }
 
 static int ocfs2_control_release(struct inode *inode, struct file *file)
@@ -755,6 +747,37 @@ static void user_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb)
 {
 }
 
+static int user_plock(struct ocfs2_cluster_connection *conn,
+                     u64 ino,
+                     struct file *file,
+                     int cmd,
+                     struct file_lock *fl)
+{
+       /*
+        * This more or less just demuxes the plock request into any
+        * one of three dlm calls.
+        *
+        * Internally, fs/dlm will pass these to a misc device, which
+        * a userspace daemon will read and write to.
+        *
+        * For now, cancel requests (which happen internally only),
+        * are turned into unlocks. Most of this function taken from
+        * gfs2_lock.
+        */
+
+       if (cmd == F_CANCELLK) {
+               cmd = F_SETLK;
+               fl->fl_type = F_UNLCK;
+       }
+
+       if (IS_GETLK(cmd))
+               return dlm_posix_get(conn->cc_lockspace, ino, file, fl);
+       else if (fl->fl_type == F_UNLCK)
+               return dlm_posix_unlock(conn->cc_lockspace, ino, file, fl);
+       else
+               return dlm_posix_lock(conn->cc_lockspace, ino, file, cmd, fl);
+}
+
 /*
  * Compare a requested locking protocol version against the current one.
  *
@@ -848,6 +871,7 @@ static struct ocfs2_stack_operations ocfs2_user_plugin_ops = {
        .dlm_unlock     = user_dlm_unlock,
        .lock_status    = user_dlm_lock_status,
        .lock_lvb       = user_dlm_lvb,
+       .plock          = user_plock,
        .dump_lksb      = user_dlm_dump_lksb,
 };