[Ocfs2-devel] [PATCH 07/10] ocfs2: add fsdlm to stackglue
Joel Becker
joel.becker at oracle.com
Wed Mar 5 17:13:55 PST 2008
From: David Teigland <teigland at redhat.com>
Add code to use fs/dlm.
[ Modified to be part of the stack_user module -- Joel ]
Signed-off-by: David Teigland <teigland at redhat.com>
Signed-off-by: Joel Becker <joel.becker at oracle.com>
---
fs/ocfs2/stack_user.c | 216 ++++++++++++++++++++++++++++++++++++++++++++++++-
fs/ocfs2/stackglue.c | 14 +++-
fs/ocfs2/stackglue.h | 19 ++++-
3 files changed, 243 insertions(+), 6 deletions(-)
diff --git a/fs/ocfs2/stack_user.c b/fs/ocfs2/stack_user.c
index 9faa678..9cb2015 100644
--- a/fs/ocfs2/stack_user.c
+++ b/fs/ocfs2/stack_user.c
@@ -24,6 +24,7 @@
#include <linux/reboot.h>
#include <asm/uaccess.h>
+#include "ocfs2.h" /* For struct ocfs2_lock_res */
#include "stackglue.h"
@@ -152,6 +153,8 @@ union ocfs2_control_message {
struct ocfs2_control_message_down u_down;
};
+static struct ocfs2_stack_plugin user_stack;
+
static atomic_t ocfs2_control_opened;
static int ocfs2_control_this_node = -1;
static struct ocfs2_protocol_version running_proto;
@@ -344,6 +347,20 @@ out_unlock:
return rc;
}
+static int ocfs2_control_get_this_node(void)
+{
+ int rc;
+
+ mutex_lock(&ocfs2_control_lock);
+ if (ocfs2_control_this_node < 0)
+ rc = -EINVAL;
+ else
+ rc = ocfs2_control_this_node;
+ mutex_unlock(&ocfs2_control_lock);
+
+ return rc;
+}
+
static int ocfs2_control_do_setnode_msg(struct file *file,
struct ocfs2_control_message_setn *msg)
{
@@ -652,13 +669,210 @@ static void ocfs2_control_exit(void)
-rc);
}
+static struct dlm_lksb *fsdlm_astarg_to_lksb(void *astarg)
+{
+ struct ocfs2_lock_res *res = astarg;
+ return &res->l_lksb.lksb_fsdlm;
+}
+
+static void fsdlm_lock_ast_wrapper(void *astarg)
+{
+ struct dlm_lksb *lksb = fsdlm_astarg_to_lksb(astarg);
+ int status = lksb->sb_status;
+
+ BUG_ON(user_stack.sp_proto == NULL);
+
+ /*
+ * For now we're punting on the issue of other non-standard errors
+ * where we can't tell if the unlock_ast or lock_ast should be called.
+ * The main "other error" that's possible is EINVAL which means the
+ * function was called with invalid args, which shouldn't be possible
+ * since the caller here is under our control. Other non-standard
+ * errors probably fall into the same category, or otherwise are fatal
+ * which means we can't carry on anyway.
+ */
+
+ if (status == -DLM_EUNLOCK || status == -DLM_ECANCEL)
+ user_stack.sp_proto->lp_unlock_ast(astarg, 0);
+ else
+ user_stack.sp_proto->lp_lock_ast(astarg);
+}
+
+static void fsdlm_blocking_ast_wrapper(void *astarg, int level)
+{
+ BUG_ON(user_stack.sp_proto == NULL);
+
+ user_stack.sp_proto->lp_blocking_ast(astarg, level);
+}
+
+static int user_dlm_lock(struct ocfs2_cluster_connection *conn,
+ int mode,
+ union ocfs2_dlm_lksb *lksb,
+ u32 flags,
+ void *name,
+ unsigned int namelen,
+ void *astarg)
+{
+ int ret;
+
+ if (!lksb->lksb_fsdlm.sb_lvbptr)
+ lksb->lksb_fsdlm.sb_lvbptr = (char *)lksb +
+ sizeof(struct dlm_lksb);
+
+ ret = dlm_lock(conn->cc_lockspace, mode, &lksb->lksb_fsdlm,
+ flags|DLM_LKF_NODLCKWT, name, namelen, 0,
+ fsdlm_lock_ast_wrapper, astarg,
+ fsdlm_blocking_ast_wrapper);
+ return ret;
+}
+
+static int user_dlm_unlock(struct ocfs2_cluster_connection *conn,
+ union ocfs2_dlm_lksb *lksb,
+ u32 flags,
+ void *astarg)
+{
+ int ret;
+
+ ret = dlm_unlock(conn->cc_lockspace, lksb->lksb_fsdlm.sb_lkid,
+ flags, &lksb->lksb_fsdlm, astarg);
+ return ret;
+}
+
+static int user_dlm_lock_status(union ocfs2_dlm_lksb *lksb)
+{
+ return lksb->lksb_fsdlm.sb_status;
+}
+
+static void *user_dlm_lvb(union ocfs2_dlm_lksb *lksb)
+{
+ return (void *)(lksb->lksb_fsdlm.sb_lvbptr);
+}
+
+static void user_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb)
+{
+}
+
+/*
+ * Compare a requested locking protocol version against the current one.
+ *
+ * If the major numbers are different, they are incompatible.
+ * If the current minor is greater than the request, they are incompatible.
+ * If the current minor is less than or equal to the request, they are
+ * compatible, and the requester should run at the current minor version.
+ */
+static int fs_protocol_compare(struct ocfs2_protocol_version *existing,
+ struct ocfs2_protocol_version *request)
+{
+ if (existing->pv_major != request->pv_major)
+ return 1;
+
+ if (existing->pv_minor > request->pv_minor)
+ return 1;
+
+ if (existing->pv_minor < request->pv_minor)
+ request->pv_minor = existing->pv_minor;
+
+ return 0;
+}
+
+static int user_cluster_connect(struct ocfs2_cluster_connection *conn)
+{
+ dlm_lockspace_t *fsdlm;
+ struct ocfs2_live_connection *control;
+ int rc = 0;
+
+ BUG_ON(conn == NULL);
+
+ rc = ocfs2_live_connection_new(conn, &control);
+ if (rc)
+ goto out;
+
+ /*
+ * running_proto must have been set before we allowed any mounts
+ * to proceed.
+ */
+ if (fs_protocol_compare(&running_proto, &conn->cc_version)) {
+ printk(KERN_ERR
+ "Unable to mount with fs locking protocol version "
+ "%u.%u because the userspace control daemon has "
+ "negotiated %u.%u\n",
+ conn->cc_version.pv_major, conn->cc_version.pv_minor,
+ running_proto.pv_major, running_proto.pv_minor);
+ rc = -EPROTO;
+ ocfs2_live_connection_drop(control);
+ goto out;
+ }
+
+ rc = dlm_new_lockspace(conn->cc_name, strlen(conn->cc_name),
+ &fsdlm, DLM_LSFL_FS, DLM_LVB_LEN);
+ if (rc) {
+ ocfs2_live_connection_drop(control);
+ goto out;
+ }
+
+ conn->cc_private = control;
+ conn->cc_lockspace = fsdlm;
+out:
+ return rc;
+}
+
+static int user_cluster_disconnect(struct ocfs2_cluster_connection *conn,
+ int hangup_pending)
+{
+ dlm_release_lockspace(conn->cc_lockspace, 2);
+ conn->cc_lockspace = NULL;
+ ocfs2_live_connection_drop(conn->cc_private);
+ conn->cc_private = NULL;
+ return 0;
+}
+
+static int user_cluster_this_node(unsigned int *this_node)
+{
+ int rc;
+
+ rc = ocfs2_control_get_this_node();
+ if (rc < 0)
+ return rc;
+
+ *this_node = rc;
+ return 0;
+}
+
+static struct ocfs2_stack_operations user_stack_ops = {
+ .connect = user_cluster_connect,
+ .disconnect = user_cluster_disconnect,
+ .this_node = user_cluster_this_node,
+ .dlm_lock = user_dlm_lock,
+ .dlm_unlock = user_dlm_unlock,
+ .lock_status = user_dlm_lock_status,
+ .lock_lvb = user_dlm_lvb,
+ .dump_lksb = user_dlm_dump_lksb,
+};
+
+static struct ocfs2_stack_plugin user_stack = {
+ .sp_name = "user",
+ .sp_ops = &user_stack_ops,
+ .sp_owner = THIS_MODULE,
+};
+
+
static int __init user_stack_init(void)
{
- return ocfs2_control_init();
+ int rc;
+
+ rc = ocfs2_control_init();
+ if (!rc) {
+ rc = ocfs2_stack_glue_register(&user_stack);
+ if (rc)
+ ocfs2_control_exit();
+ }
+
+ return rc;
}
static void __exit user_stack_exit(void)
{
+ ocfs2_stack_glue_unregister(&user_stack);
ocfs2_control_exit();
}
diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index bf45d9b..119f60c 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -228,13 +228,20 @@ void ocfs2_stack_glue_set_locking_protocol(struct ocfs2_locking_protocol *proto)
EXPORT_SYMBOL_GPL(ocfs2_stack_glue_set_locking_protocol);
+/*
+ * The ocfs2_dlm_lock() and ocfs2_dlm_unlock() functions take
+ * "struct ocfs2_lock_res *astarg" instead of "void *astarg" because the
+ * underlying stack plugins need to pilfer the lksb off of the lock_res.
+ * If some other structure needs to be passed as an astarg, the plugins
+ * will need to be given a different avenue to the lksb.
+ */
int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
int mode,
union ocfs2_dlm_lksb *lksb,
u32 flags,
void *name,
unsigned int namelen,
- void *astarg)
+ struct ocfs2_lock_res *astarg)
{
BUG_ON(lproto == NULL);
@@ -246,7 +253,7 @@ EXPORT_SYMBOL_GPL(ocfs2_dlm_lock);
int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn,
union ocfs2_dlm_lksb *lksb,
u32 flags,
- void *astarg)
+ struct ocfs2_lock_res *astarg)
{
BUG_ON(lproto == NULL);
@@ -360,7 +367,8 @@ void ocfs2_cluster_hangup(const char *group, int grouplen)
BUG_ON(group == NULL);
BUG_ON(group[grouplen] != '\0');
- active_stack->sp_ops->hangup(group, grouplen);
+ if (active_stack->sp_ops->hangup)
+ active_stack->sp_ops->hangup(group, grouplen);
/* cluster_disconnect() was called with hangup_pending==1 */
ocfs2_stack_driver_put();
diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h
index d88bc65..005e4f1 100644
--- a/fs/ocfs2/stackglue.h
+++ b/fs/ocfs2/stackglue.h
@@ -26,6 +26,7 @@
#include <linux/dlmconstants.h>
#include "dlm/dlmapi.h"
+#include <linux/dlm.h>
/*
* dlmconstants.h does not have a LOCAL flag. We hope to remove it
@@ -60,6 +61,17 @@ struct ocfs2_locking_protocol {
void (*lp_unlock_ast)(void *astarg, int error);
};
+
+/*
+ * The dlm_lockstatus struct includes lvb space, but the dlm_lksb struct only
+ * has a pointer to separately allocated lvb space. This struct exists only to
+ * include in the lksb union to make space for a combined dlm_lksb and lvb.
+ */
+struct fsdlm_lksb_plus_lvb {
+ struct dlm_lksb lksb;
+ char lvb[DLM_LVB_LEN];
+};
+
/*
* A union of all lock status structures. We define it here so that the
* size of the union is known. Lock status structures are embedded in
@@ -67,6 +79,8 @@ struct ocfs2_locking_protocol {
*/
union ocfs2_dlm_lksb {
struct dlm_lockstatus lksb_o2dlm;
+ struct dlm_lksb lksb_fsdlm;
+ struct fsdlm_lksb_plus_lvb padding;
};
/*
@@ -221,17 +235,18 @@ int ocfs2_cluster_disconnect(struct ocfs2_cluster_connection *conn,
void ocfs2_cluster_hangup(const char *group, int grouplen);
int ocfs2_cluster_this_node(unsigned int *node);
+struct ocfs2_lock_res;
int ocfs2_dlm_lock(struct ocfs2_cluster_connection *conn,
int mode,
union ocfs2_dlm_lksb *lksb,
u32 flags,
void *name,
unsigned int namelen,
- void *astarg);
+ struct ocfs2_lock_res *astarg);
int ocfs2_dlm_unlock(struct ocfs2_cluster_connection *conn,
union ocfs2_dlm_lksb *lksb,
u32 flags,
- void *astarg);
+ struct ocfs2_lock_res *astarg);
int ocfs2_dlm_lock_status(union ocfs2_dlm_lksb *lksb);
void *ocfs2_dlm_lvb(union ocfs2_dlm_lksb *lksb);
--
1.5.3.8
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