ocfs2: Create ocfs2_stack_operations and split out the o2cb stack.

Define the ocfs2_stack_operations structure.  Build o2cb_stack_ops from
all of the o2cb-specific stack functions.  Change the generic stack glue
functions to call the stack_ops instead of the o2cb functions directly.

The o2cb functions are moved to stack_o2cb.c.  The headers are cleaned up
to where only needed headers are included.

In this code, stackglue.c and stack_o2cb.c refer to some shared
extern variables.  When they become modules, that will change.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

1 files changed, 15 insertions, 370 deletions

diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index e35dde6217f5..e197367b6bd6 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -19,204 +19,17 @@
  */
 
 #include <linux/slab.h>
-#include <linux/crc32.h>
 #include <linux/kmod.h>
 
 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
 #include <linux/fs.h>
 
 #include "cluster/masklog.h"
-#include "cluster/nodemanager.h"
-#include "cluster/heartbeat.h"
 
 #include "stackglue.h"
 
-static struct ocfs2_locking_protocol *lproto;
-
-struct o2dlm_private {
-        struct dlm_eviction_cb op_eviction_cb;
-};
-
-/* These should be identical */
-#if (DLM_LOCK_IV != LKM_IVMODE)
-# error Lock modes do not match
-#endif
-#if (DLM_LOCK_NL != LKM_NLMODE)
-# error Lock modes do not match
-#endif
-#if (DLM_LOCK_CR != LKM_CRMODE)
-# error Lock modes do not match
-#endif
-#if (DLM_LOCK_CW != LKM_CWMODE)
-# error Lock modes do not match
-#endif
-#if (DLM_LOCK_PR != LKM_PRMODE)
-# error Lock modes do not match
-#endif
-#if (DLM_LOCK_PW != LKM_PWMODE)
-# error Lock modes do not match
-#endif
-#if (DLM_LOCK_EX != LKM_EXMODE)
-# error Lock modes do not match
-#endif
-static inline int mode_to_o2dlm(int mode)
-{
-        BUG_ON(mode > LKM_MAXMODE);
-
-        return mode;
-}
-
-#define map_flag(_generic, _o2dlm)              \
-        if (flags & (_generic)) {               \
-                flags &= ~(_generic);           \
-                o2dlm_flags |= (_o2dlm);        \
-        }
-static int flags_to_o2dlm(u32 flags)
-{
-        int o2dlm_flags = 0;
-
-        map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE);
-        map_flag(DLM_LKF_CANCEL, LKM_CANCEL);
-        map_flag(DLM_LKF_CONVERT, LKM_CONVERT);
-        map_flag(DLM_LKF_VALBLK, LKM_VALBLK);
-        map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK);
-        map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN);
-        map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE);
-        map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT);
-        map_flag(DLM_LKF_LOCAL, LKM_LOCAL);
-
-        /* map_flag() should have cleared every flag passed in */
-        BUG_ON(flags != 0);
-
-        return o2dlm_flags;
-}
-#undef map_flag
-
-/*
- * Map an o2dlm status to standard errno values.
- *
- * o2dlm only uses a handful of these, and returns even fewer to the
- * caller. Still, we try to assign sane values to each error.
- *
- * The following value pairs have special meanings to dlmglue, thus
- * the right hand side needs to stay unique - never duplicate the
- * mapping elsewhere in the table!
- *
- * DLM_NORMAL:          0
- * DLM_NOTQUEUED:       -EAGAIN
- * DLM_CANCELGRANT:     -EBUSY
- * DLM_CANCEL:          -DLM_ECANCEL
- */
-/* Keep in sync with dlmapi.h */
-static int status_map[] = {
-        [DLM_NORMAL]                    = 0,            /* Success */
-        [DLM_GRANTED]                   = -EINVAL,
-        [DLM_DENIED]                    = -EACCES,
-        [DLM_DENIED_NOLOCKS]            = -EACCES,
-        [DLM_WORKING]                   = -EACCES,
-        [DLM_BLOCKED]                   = -EINVAL,
-        [DLM_BLOCKED_ORPHAN]            = -EINVAL,
-        [DLM_DENIED_GRACE_PERIOD]       = -EACCES,
-        [DLM_SYSERR]                    = -ENOMEM,      /* It is what it is */
-        [DLM_NOSUPPORT]                 = -EPROTO,
-        [DLM_CANCELGRANT]               = -EBUSY,       /* Cancel after grant */
-        [DLM_IVLOCKID]                  = -EINVAL,
-        [DLM_SYNC]                      = -EINVAL,
-        [DLM_BADTYPE]                   = -EINVAL,
-        [DLM_BADRESOURCE]               = -EINVAL,
-        [DLM_MAXHANDLES]                = -ENOMEM,
-        [DLM_NOCLINFO]                  = -EINVAL,
-        [DLM_NOLOCKMGR]                 = -EINVAL,
-        [DLM_NOPURGED]                  = -EINVAL,
-        [DLM_BADARGS]                   = -EINVAL,
-        [DLM_VOID]                      = -EINVAL,
-        [DLM_NOTQUEUED]                 = -EAGAIN,      /* Trylock failed */
-        [DLM_IVBUFLEN]                  = -EINVAL,
-        [DLM_CVTUNGRANT]                = -EPERM,
-        [DLM_BADPARAM]                  = -EINVAL,
-        [DLM_VALNOTVALID]               = -EINVAL,
-        [DLM_REJECTED]                  = -EPERM,
-        [DLM_ABORT]                     = -EINVAL,
-        [DLM_CANCEL]                    = -DLM_ECANCEL, /* Successful cancel */
-        [DLM_IVRESHANDLE]               = -EINVAL,
-        [DLM_DEADLOCK]                  = -EDEADLK,
-        [DLM_DENIED_NOASTS]             = -EINVAL,
-        [DLM_FORWARD]                   = -EINVAL,
-        [DLM_TIMEOUT]                   = -ETIMEDOUT,
-        [DLM_IVGROUPID]                 = -EINVAL,
-        [DLM_VERS_CONFLICT]             = -EOPNOTSUPP,
-        [DLM_BAD_DEVICE_PATH]           = -ENOENT,
-        [DLM_NO_DEVICE_PERMISSION]      = -EPERM,
-        [DLM_NO_CONTROL_DEVICE]         = -ENOENT,
-        [DLM_RECOVERING]                = -ENOTCONN,
-        [DLM_MIGRATING]                 = -ERESTART,
-        [DLM_MAXSTATS]                  = -EINVAL,
-};
-
-static int dlm_status_to_errno(enum dlm_status status)
-{
-        BUG_ON(status > (sizeof(status_map) / sizeof(status_map[0])));
+struct ocfs2_locking_protocol *stack_glue_lproto;
 
-        return status_map[status];
-}
-
-static void o2dlm_lock_ast_wrapper(void *astarg)
-{
-        BUG_ON(lproto == NULL);
-
-        lproto->lp_lock_ast(astarg);
-}
-
-static void o2dlm_blocking_ast_wrapper(void *astarg, int level)
-{
-        BUG_ON(lproto == NULL);
-
-        lproto->lp_blocking_ast(astarg, level);
-}
-
-static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
-{
-        int error = dlm_status_to_errno(status);
-
-        BUG_ON(lproto == NULL);
-
-        /*
-         * In o2dlm, you can get both the lock_ast() for the lock being
-         * granted and the unlock_ast() for the CANCEL failing.  A
-         * successful cancel sends DLM_NORMAL here.  If the
-         * lock grant happened before the cancel arrived, you get
-         * DLM_CANCELGRANT.
-         *
-         * There's no need for the double-ast.  If we see DLM_CANCELGRANT,
-         * we just ignore it.  We expect the lock_ast() to handle the
-         * granted lock.
-         */
-        if (status == DLM_CANCELGRANT)
-                return;
-
-        lproto->lp_unlock_ast(astarg, error);
-}
-
-static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn,
-                         int mode,
-                         union ocfs2_dlm_lksb *lksb,
-                         u32 flags,
-                         void *name,
-                         unsigned int namelen,
-                         void *astarg)
-{
-        enum dlm_status status;
-        int o2dlm_mode = mode_to_o2dlm(mode);
-        int o2dlm_flags = flags_to_o2dlm(flags);
-        int ret;
-
-        status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
-                         o2dlm_flags, name, namelen,
-                         o2dlm_lock_ast_wrapper, astarg,
-                         o2dlm_blocking_ast_wrapper);
-        ret = dlm_status_to_errno(status);
-        return ret;
-}
 
 int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
                    int mode,
@@ -226,25 +39,10 @@ int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
                    unsigned int namelen,
                    void *astarg)
 {
-        BUG_ON(lproto == NULL);
-
-        return o2cb_dlm_lock(conn, mode, lksb, flags,
-                             name, namelen, astarg);
-}
-
-static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
-                           union ocfs2_dlm_lksb *lksb,
-                           u32 flags,
-                           void *astarg)
-{
-        enum dlm_status status;
-        int o2dlm_flags = flags_to_o2dlm(flags);
-        int ret;
+        BUG_ON(stack_glue_lproto == NULL);
 
-        status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
-                           o2dlm_flags, o2dlm_unlock_ast_wrapper, astarg);
-        ret = dlm_status_to_errno(status);
-        return ret;
+        return o2cb_stack_ops.dlm_lock(conn, mode, lksb, flags,
+                                       name, namelen, astarg);
 }
 
 int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn,
@@ -252,19 +50,14 @@ int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn,
                      u32 flags,
                      void *astarg)
 {
-        BUG_ON(lproto == NULL);
+        BUG_ON(stack_glue_lproto == NULL);
 
-        return o2cb_dlm_unlock(conn, lksb, flags, astarg);
-}
-
-static int o2cb_dlm_lock_status(union ocfs2_dlm_lksb *lksb)
-{
-        return dlm_status_to_errno(lksb->lksb_o2dlm.status);
+        return o2cb_stack_ops.dlm_unlock(conn, lksb, flags, astarg);
 }
 
 int ocfs2_dlm_lock_status(union ocfs2_dlm_lksb *lksb)
 {
-        return o2cb_dlm_lock_status(lksb);
+        return o2cb_stack_ops.lock_status(lksb);
 }
 
 /*
@@ -272,94 +65,14 @@ int ocfs2_dlm_lock_status(union ocfs2_dlm_lksb *lksb)
  * don't cast at the glue level.  The real answer is that the header
  * ordering is nigh impossible.
  */
-static void *o2cb_dlm_lvb(union ocfs2_dlm_lksb *lksb)
-{
-        return (void *)(lksb->lksb_o2dlm.lvb);
-}
-
 void *ocfs2_dlm_lvb(union ocfs2_dlm_lksb *lksb)
 {
-        return o2cb_dlm_lvb(lksb);
-}
-
-static void o2cb_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb)
-{
-        dlm_print_one_lock(lksb->lksb_o2dlm.lockid);
+        return o2cb_stack_ops.lock_lvb(lksb);
 }
 
 void ocfs2_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb)
 {
-        o2cb_dlm_dump_lksb(lksb);
-}
-
-/*
- * Called from the dlm when it's about to evict a node. This is how the
- * classic stack signals node death.
- */
-static void o2dlm_eviction_cb(int node_num, void *data)
-{
-        struct ocfs2_cluster_connection *conn = data;
-
-        mlog(ML_NOTICE, "o2dlm has evicted node %d from group %.*s\n",
-             node_num, conn->cc_namelen, conn->cc_name);
-
-        conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
-}
-
-static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
-{
-        int rc = 0;
-        u32 dlm_key;
-        struct dlm_ctxt *dlm;
-        struct o2dlm_private *priv;
-        struct dlm_protocol_version dlm_version;
-
-        BUG_ON(conn == NULL);
-
-        /* for now we only have one cluster/node, make sure we see it
-         * in the heartbeat universe */
-        if (!o2hb_check_local_node_heartbeating()) {
-                rc = -EINVAL;
-                goto out;
-        }
-
-        priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
-        if (!priv) {
-                rc = -ENOMEM;
-                goto out_free;
-        }
-
-        /* This just fills the structure in.  It is safe to pass conn. */
-        dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
-                              conn);
-
-        conn->cc_private = priv;
-
-        /* used by the dlm code to make message headers unique, each
-         * node in this domain must agree on this. */
-        dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen);
-        dlm_version.pv_major = conn->cc_version.pv_major;
-        dlm_version.pv_minor = conn->cc_version.pv_minor;
-
-        dlm = dlm_register_domain(conn->cc_name, dlm_key, &dlm_version);
-        if (IS_ERR(dlm)) {
-                rc = PTR_ERR(dlm);
-                mlog_errno(rc);
-                goto out_free;
-        }
-
-        conn->cc_version.pv_major = dlm_version.pv_major;
-        conn->cc_version.pv_minor = dlm_version.pv_minor;
-        conn->cc_lockspace = dlm;
-
-        dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
-
-out_free:
-        if (rc && conn->cc_private)
-                kfree(conn->cc_private);
-
-out:
-        return rc;
+        o2cb_stack_ops.dump_lksb(lksb);
 }
 
 int ocfs2_cluster_connect(const char *group,
@@ -394,9 +107,9 @@ int ocfs2_cluster_connect(const char *group,
         new_conn->cc_recovery_data = recovery_data;
 
         /* Start the new connection at our maximum compatibility level */
-        new_conn->cc_version = lproto->lp_max_version;
+        new_conn->cc_version = stack_glue_lproto->lp_max_version;
 
-        rc = o2cb_cluster_connect(new_conn);
+        rc = o2cb_stack_ops.connect(new_conn);
         if (rc) {
                 mlog_errno(rc);
                 goto out_free;
@@ -412,29 +125,13 @@ out:
         return rc;
 }
 
-
-static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn)
-{
-        struct dlm_ctxt *dlm = conn->cc_lockspace;
-        struct o2dlm_private *priv = conn->cc_private;
-
-        dlm_unregister_eviction_cb(&priv->op_eviction_cb);
-        conn->cc_private = NULL;
-        kfree(priv);
-
-        dlm_unregister_domain(dlm);
-        conn->cc_lockspace = NULL;
-
-        return 0;
-}
-
 int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn)
 {
         int ret;
 
         BUG_ON(conn == NULL);
 
-        ret = o2cb_cluster_disconnect(conn);
+        ret = o2cb_stack_ops.disconnect(conn);
 
         /* XXX Should we free it anyway? */
         if (!ret)
@@ -443,75 +140,23 @@ int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn)
         return ret;
 }
 
-static void o2hb_stop(const char *group)
-{
-        int ret;
-        char *argv[5], *envp[3];
-
-        argv[0] = (char *)o2nm_get_hb_ctl_path();
-        argv[1] = "-K";
-        argv[2] = "-u";
-        argv[3] = (char *)group;
-        argv[4] = NULL;
-
-        mlog(0, "Run: %s %s %s %s\n", argv[0], argv[1], argv[2], argv[3]);
-
-        /* minimal command environment taken from cpu_run_sbin_hotplug */
-        envp[0] = "HOME=/";
-        envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
-        envp[2] = NULL;
-
-        ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
-        if (ret < 0)
-                mlog_errno(ret);
-}
-
-/*
- * Hangup is a hack for tools compatibility.  Older ocfs2-tools software
- * expects the filesystem to call "ocfs2_hb_ctl" during unmount.  This
- * happens regardless of whether the DLM got started, so we can't do it
- * in ocfs2_cluster_disconnect().  We bring the o2hb_stop() function into
- * the glue and provide a "hangup" API for super.c to call.
- *
- * Other stacks will eventually provide a NULL ->hangup() pointer.
- */
-static void o2cb_cluster_hangup(const char *group, int grouplen)
-{
-        o2hb_stop(group);
-}
-
 void ocfs2_cluster_hangup(const char *group, int grouplen)
 {
         BUG_ON(group == NULL);
         BUG_ON(group[grouplen] != '\0');
 
-        o2cb_cluster_hangup(group, grouplen);
-}
-
-static int o2cb_cluster_this_node(unsigned int *node)
-{
-        int node_num;
-
-        node_num = o2nm_this_node();
-        if (node_num == O2NM_INVALID_NODE_NUM)
-                return -ENOENT;
-
-        if (node_num >= O2NM_MAX_NODES)
-                return -EOVERFLOW;
-
-        *node = node_num;
-        return 0;
+        o2cb_stack_ops.hangup(group, grouplen);
 }
 
 int ocfs2_cluster_this_node(unsigned int *node)
 {
-        return o2cb_cluster_this_node(node);
+        return o2cb_stack_ops.this_node(node);
 }
 
 void ocfs2_stack_glue_set_locking_protocol(struct ocfs2_locking_protocol *proto)
 {
         BUG_ON(proto != NULL);
 
-        lproto = proto;
+        stack_glue_lproto = proto;
 }