From e3dad42bf993a0f24eb6e46152356c9b119c15e8 Mon Sep 17 00:00:00 2001 From: Joel Becker Date: Fri, 1 Feb 2008 15:02:36 -0800 Subject: 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 Signed-off-by: Mark Fasheh --- fs/ocfs2/stackglue.h | 123 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 121 insertions(+), 2 deletions(-) (limited to 'fs/ocfs2/stackglue.h') diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h index decb147106f..083632215dc 100644 --- a/fs/ocfs2/stackglue.h +++ b/fs/ocfs2/stackglue.h @@ -25,6 +25,8 @@ #include #include +#include "dlm/dlmapi.h" + /* * dlmconstants.h does not have a LOCAL flag. We hope to remove it * some day, but right now we need it. Let's fake it. This value is larger @@ -39,13 +41,18 @@ #define GROUP_NAME_MAX 64 -#include "dlm/dlmapi.h" - +/* + * ocfs2_protocol_version changes when ocfs2 does something different in + * its inter-node behavior. See dlmglue.c for more information. + */ struct ocfs2_protocol_version { u8 pv_major; u8 pv_minor; }; +/* + * The ocfs2_locking_protocol defines the handlers called on ocfs2's behalf. + */ struct ocfs2_locking_protocol { struct ocfs2_protocol_version lp_max_version; void (*lp_lock_ast)(void *astarg); @@ -53,10 +60,20 @@ struct ocfs2_locking_protocol { void (*lp_unlock_ast)(void *astarg, int error); }; +/* + * 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 + * ocfs2 inodes. + */ union ocfs2_dlm_lksb { struct dlm_lockstatus lksb_o2dlm; }; +/* + * A cluster connection. Mostly opaque to ocfs2, the connection holds + * state for the underlying stack. ocfs2 does use cc_version to determine + * locking compatibility. + */ struct ocfs2_cluster_connection { char cc_name[GROUP_NAME_MAX]; int cc_namelen; @@ -67,6 +84,106 @@ struct ocfs2_cluster_connection { void *cc_private; }; +/* + * Each cluster stack implements the stack operations structure. Not used + * in the ocfs2 code, the stackglue code translates generic cluster calls + * into stack operations. + */ +struct ocfs2_stack_operations { + /* + * The fs code calls ocfs2_cluster_connect() to attach a new + * filesystem to the cluster stack. The ->connect() op is passed + * an ocfs2_cluster_connection with the name and recovery field + * filled in. + * + * The stack must set up any notification mechanisms and create + * the filesystem lockspace in the DLM. The lockspace should be + * stored on cc_lockspace. Any other information can be stored on + * cc_private. + * + * ->connect() must not return until it is guaranteed that + * + * - Node down notifications for the filesystem will be recieved + * and passed to conn->cc_recovery_handler(). + * - Locking requests for the filesystem will be processed. + */ + int (*connect)(struct ocfs2_cluster_connection *conn); + + /* + * The fs code calls ocfs2_cluster_disconnect() when a filesystem + * no longer needs cluster services. All DLM locks have been + * dropped, and recovery notification is being ignored by the + * fs code. The stack must disengage from the DLM and discontinue + * recovery notification. + * + * Once ->disconnect() has returned, the connection structure will + * be freed. Thus, a stack must not return from ->disconnect() + * until it will no longer reference the conn pointer. + */ + int (*disconnect)(struct ocfs2_cluster_connection *conn); + + /* + * ocfs2_cluster_hangup() exists for compatibility with older + * ocfs2 tools. Only the classic stack really needs it. As such + * ->hangup() is not required of all stacks. See the comment by + * ocfs2_cluster_hangup() for more details. + */ + void (*hangup)(const char *group, int grouplen); + + /* + * ->this_node() returns the cluster's unique identifier for the + * local node. + */ + int (*this_node)(unsigned int *node); + + /* + * Call the underlying dlm lock function. The ->dlm_lock() + * callback should convert the flags and mode as appropriate. + * + * ast and bast functions are not part of the call because the + * stack will likely want to wrap ast and bast calls before passing + * them to stack->sp_proto. + */ + int (*dlm_lock)(struct ocfs2_cluster_connection *conn, + int mode, + union ocfs2_dlm_lksb *lksb, + u32 flags, + void *name, + unsigned int namelen, + void *astarg); + + /* + * Call the underlying dlm unlock function. The ->dlm_unlock() + * function should convert the flags as appropriate. + * + * The unlock ast is not passed, as the stack will want to wrap + * it before calling stack->sp_proto->lp_unlock_ast(). + */ + int (*dlm_unlock)(struct ocfs2_cluster_connection *conn, + union ocfs2_dlm_lksb *lksb, + u32 flags, + void *astarg); + + /* + * Return the status of the current lock status block. The fs + * code should never dereference the union. The ->lock_status() + * callback pulls out the stack-specific lksb, converts the status + * to a proper errno, and returns it. + */ + int (*lock_status)(union ocfs2_dlm_lksb *lksb); + + /* + * Pull the lvb pointer off of the stack-specific lksb. + */ + void *(*lock_lvb)(union ocfs2_dlm_lksb *lksb); + + /* + * This is an optoinal debugging hook. If provided, the + * stack can dump debugging information about this lock. + */ + void (*dump_lksb)(union ocfs2_dlm_lksb *lksb); +}; + int ocfs2_cluster_connect(const char *group, int grouplen, void (*recovery_handler)(int node_num, @@ -95,4 +212,6 @@ void ocfs2_dlm_dump_lksb(union ocfs2_dlm_lksb *lksb); void ocfs2_stack_glue_set_locking_protocol(struct ocfs2_locking_protocol *proto); +extern struct ocfs2_locking_protocol *stack_glue_lproto; +extern struct ocfs2_stack_operations o2cb_stack_ops; #endif /* STACKGLUE_H */ -- cgit v1.2.3